Handy Points for FCPS

Handy points

Question Id Notes
5 Medullary sponge kidney characterized by cystic dilatations for the medullary collecting ducts. Kidney tones are the most common complication of this disease.
6 Renal angiomyolipoma is a benign tumor composed of blood vessels, smooth muscle and fat. Part of the Tuberous sclerosis that is autosomal dominant.
15 symmetrical enlargement of the ventriculi is characteristic of communicating hydrocephalus. It occurs secondary to dysfunction or obliteration of subarachnoid villi.
17 Micturition reflex at 3 centers: sacral micturition center, pontine micturition center and cerebral cortex. Sacral mi

cturition center at s2-s4 contracts the bladder wall. Cerebral cortex inhibits this center. Pontine center coordinates relaxation of external urethral sphincter with bladder contraction during voiding. Normal pressure hydrocephalus stretches the descencing cortical fibers thus disinhbiting the sacral micturition center -resulting in incontinence.

18 cells prone to hypoxic ischemia are the pyramidal cells of the hippocampus and neocortex and the purkinje cells of teh cerebellum.
20 macrophages move to the area of ischemic infarct 3-5 days after the onset of ischemia. They phagocytize fragments of neurons, myelin and necrotic debris. Astrocytes then form the glial scar.
22 Lacunar infarcts are due to hypertensive arteriolosclerosis of small, penetrating arterioles. Pure motor hemiparesis — posterior limb of the internal capsule.Pure sensory stroke — ventroposterolateral or ventroposteromedial thalamus. Ataxia-hemiplegia syndrome — base of the pons.Dysarthria-clumsy hand syndrome – the base of the pons or the genu of the internal capsule.
24 Crescents in RPGN consist of glomerular parietal cells, monocytes, macrophages and abundant fibrin
28 Nephrotic syndrome — increased glomerular capillary permeability to proteins leads to proteinuria and loss of proteins results in decrease in oncotic pressure so there is generalized edema. Body tries to compensate for the decreased renal perfusion pressure due to loss of fluid by activcating the renin-angiotensin system releasing aldosterone and ADH. Liver synthesizes lipoproteins to replace lost proteins.
37 Transmural infarction (STEMI) is most commonly caused by and acute plaque change (rupture) which produces a superimposed thrombus that completely occludes the involved coronary artery.
44 The envelope proteins of Hep C vary their antigenic structures and the producion of host antibodies lags behind the production of new mutant strains of HCV.
54 Cavernous hemangioma is the most common benign liver tumor.
57 Aflatoxin is responsible for inducing hepatocellular carcinoma. This is done via G:C —> T:A transversion in codon 249 of the p53 gene.
58 Hep B virus integrates its DNA into the host genome, thus elevating the risk of hepatocellular carcinoma.
60 universal vaccination would be helpful in protecting children against HBV and would cause a steep decline in the worldwide incidence of hepatocellular carcinoma.
62 Enteric bacteria can cause hepatic abscess by ascending the biliary tract or directly invading from an adjacent area. Staph aureus can cause hepatic abscess through hematogenous route.
63 ophthalmoplegia, ataxia and confusion form the triad of Wernicke syndrome. Most of these sx resolve after thiamine administration. Korsakoff syndrome is a complication of wernicke encephalopathy. The hallmarks of korsakoff syndrome are permanent memory loss and confabulation. Korsakoff syndrome is a/w damage of the medial dorsal nucleus of the thalamusthat leads to confabulation. Thaimine infusion doesn’t treat korsakoff sx.
65 Myelopathy associated with vitamin B12 deficiency is called subacute, combined degeneration. Combined refers to degeneration of both ascending (dorsal columns) and descending (corticospinal tract) pathways. Loss of position and vibration sensation, ataxia, and spastic paresis are common manifestations.
66 GBS is immune-mediated acute demyelination of the peripheral nerves. It is often preceded by a febrile illness and strong a/w Campylobacter jejuni infection. Sx are ascending muscle weakness and areflexia. Endoneural inflammatory infiltrate. Abs formed against ganglioside-like substance in the LPS layer of bacteria cross-react with ganglioside components of myelin.
68 Estrogen-induced cholesterol hypersecretion via increased activity of HMGcoA reductase and progestone-induced gallbladder hypomotility (reduces bile acid secretion and slows gallbladder emptying) are responsible for the increased incidence of cholelithiasis in pregnant women and women who use oral contraceptives.
70 Brown pigment stones arise from bacterial infection, due to the relase of B-glucoronidase by injured hepatocytes and bacteria. The presence of this enzyme contributes to the hydrolysis of bilirubin glucoronides and increases the amount of unconjugated bilirubin in bile.
71 Gallbladder hypomotility often results in bile precipitation and formation of biliary sludge.
74 carcinoid syndrome can cause right-sided endocardial fibrosis. Carcinoid heart disease correlates with plasma levels of serotonin and urinary secretion of serotonin metabolite 5-hydroxyindoleacetic acid.
75 Aortic stenosis–high systolic pressure gradient between aorta and the left ventricle. Aortic stenosis can cause dilated cardiomyopathy. Dilational cardiomyopathy is characterized by ventricular dilatation and systolic dysfunction. Aortic stenosis causes left ventricular outflow obstruction.
77 Total parenteral nutrition can induce gallstone formation secondary to biliary stasis from absent enteral stimulation or disturbance of the enterohepatic bile acid circulation in those with ileal resections.
78 To reduce gallstone formation, cholesterol levels should be kept low, bile acid quantities should be kept high along with high levels of phosphatidylcholine, a phospholipid that renders cholesterol soluble thus decreasing the formation of gallstones.
79 Acute calculous cholecystitis is due to obstruction of the gallbladder at the neck or the cystic duct.
80 HIDA scan is a nuclear medicine hepatobiliary scan that is necessary for a definitive diagnosis of acute calculous cholecystitis.
81 Acute acalculous cholecystitis is an acute inflammation of the gallbladder in the absence of gallstones and arises secondary to gallbladder statis and ischemia. Physical examinaition demonstrates jaundice and a palpable right upper quadrant mass, both of which are not seen in cases of calculous cholecystitis.
84 QT interval is the cardiomyocyte action potential duration. determined by K+ currents.
87 Porcelain gallbladder — dystrophic calcification — calcium deposits that outline the gallbladder. Porcelain gallbladder can eventually develop into gallbladder carcinoma so cholecystectomy is recommended.
88 Pneumobilia is suggestive of Gallstone ileus, which is a type of mechanical bowel obstruction caused when a large gallstone erodes into the intestinal lumen through a cholecystoenteric fistula. symptoms inclue crampy abdominal pain, vomiting and abdominal distention.
90 Wolff-parkinson-white syndrome triad on ECG: shortened PR interval, a delta wave at the start of the QRS complex and a widened QRS-interval.
92 CHF can be due to diffuse ischemic heart disease or dilated cardiomyopathy. Dilated cardiomyopahty is characterized by ventricular dilatation, contractile dysfunction. Chronic hypertension is the main cause of left ventricular diastolic dysfunction —concentric ventricular hypertrophy. Dilated cardiomyopathy of the left ventricle is characterized by ventricular dilatation, LV systolic dysfunction and signs and symptoms of CHF.Diastolic dysfunction occurs in hypertensive hear
93 Amyloidosis can cause restrictive cardiomyopathy. Diastolic dysfunction is main reason of heart failure in restrictive cardiomyopathy
95 Hypertrophic cardiomyopathy is an autosomal dominant condition.
97 pericardial knock is present in constrictive pericarditis, a high frequency precordial sound heard in early diastole in pts with constrictive pericarditis. Occurs earlier than s3 ventricular gallop Acute-onset, mid-chest, pleuritic pain that decreases on sitting up and leaning forward is characteristic of acute pericarditis. pericardial friction rub is most striking physical finding
99 To clarify the importance of moderately elevated alkaline phosphatase, the hepatic gamma glutamyl transpeptidase (GGTP) should be evaluated.
100 Hyperestrinism in alcoholic cirrhosis arises due to decreased catabolism of estrogens as well as increased sex hormone-binding globulin (which decreases the free testosterone-to-estrogen ratio). This imbalance leads to gynecomastia, testicular atrophy, decreased body hair and spider angiomata.
102 Hepatic encephalopathy is secondary due to increased levels of ammonia in circulation. It is precipitated by a stressor that alters ammonia balance such as GI bleed. Ammonia initially enters via the GI tract from enterocytic catabolism of glutamine and bacterical catabolism of dietary protein in the colon. Enters the liver via portal vein for detoxification but due to damaged liver, ammonia is released into blood and it accumulates.
103 Dimorphic fungi grow as molds at 25-30c and as yeast at body temp (35-37). Medically imp dimorphic fungi include Sporothrix, coccidioides, Histoplasma, Blastomyces (found in great lakes regio) and paracoccidioides.
104 Pityriasis Versicolor is a condition of hypo- or hyperpigmented skin patches caused by fungus Malassezia furfur. KOH prepartaion of skin scrapings reveals a sphaghetti and meatballs appearance on microscopy.
105 Neutropenia is associated with leukemias and lymphomas. Neutropenic pts are at risk for infection with aspergillus fumigatus. It produces septate hyphae with V-shaped branching. It causes invasive aspergillosis, aspergillomas and allergic pulmonary aspergillosis (ABPA).
106 Mucormycosis is caused by opportunistic infection Rhizopus, mucor and absidia species. It includes paranasal sinus involvement in a diabetic or immunosuppressed pt. The fungi form broad nonseptate hyphae that branch at right angles.
108 Colonizing aspergillosis –occurs in old lung cavities and don not invade lung tissue forming fungus balls. Radiopaque structure that shifts when the pt changes position. Invasive aspergillosis has primary lung involvement with cough, hemoptysis, pleuritic chest pain and fever and granuloma formation and necrotizing pneumonia. Allergic bronchopoulomnary aspergillosis (ABPA) has wheezing, fever and migratory pulmonary infiltrates.
110 use of broad-spectrum antibiotics suppresses the normal bacterial flora of the vagina and facilitates candida overgrowth. Common triggers of candida vaginitis include antibiotic use, contraceptive use, corticosteroid therapy, uncontrolled diabetes mellitus and any other cause of immunosuppression.
111 Oral thrush by candida albicans infection. It is a/w wearing dentures, diabetes mellitus and immunosuppression. Unexplained oral thrush in an otherwise healthy person suggests the possibility of HIV infection.
112 Systemic infection of Candida is prevented by neutrophils, whereas local defense against candida is performed by T-cells.
117 Mucicarmine stain is used to detect the polysaccharide capsule of Cryptococcus neoformans. This is the only pathogenic fungus that has a polysaccharide capsule. It appears red on mucicarmine stain and as clear unstained zone with india ink. Methenamine silver stain can also be used to visualize the pathogen.
118 Only fungi with soluble polysaccharide antigen is cryptococcus neoformans and it is a budding yeast. Pt’s headache, confusion and inflammatory increase CSF protein and CSF pleocytosis are typical sx of meningitis.
119 candida albicans is a normal inhabitant of the GI tract (including the oral cavity). The presence of candida in sputum does not indicate disease.
120 Blastomyces dermadititidis is a dimorphic fungus that is seen in tissue as round yeasts with doubly refractive walls and broad based budding. It is endemic to the great lakes and the ohio and mississippi River regions.
121 Blastomycosis dermatitidis is a dimorphic fungus that can cause pulmonary infections in immunocompetent people. Blastomyces is transmitted by respiratory route, entering the lungs and transforming into yeast form (thermal dimorphism). Pulmonary blastomycosis is characterized by granuloma formation. In immunocompromised hosts, it may lead to disseminated mycosis (fever, pulmonary sx, skin and bone involvement).
124 Pernicious anemia due to immune destruction of gastric mucosa which results in chronic atrophic gastritis characterized by loss of intrinsic factor secreting parietal cells, marked lymphocytic and plasma cell infiltration and megaloblastic changes in mucosal cells.
125 Ulcers arising in proximal duodenum in association with trauma and burns is called Curling ulcers (decreased plasma volume). Ulcers in esophagus, stomach or duodenum with respect to high intracranial pressure and prone to perforation are called Cushing’s ulcers (Increased vagal stimulation which increase Ach release and thus H+ production.
129 Brunner’s glands are on the only submucosal glands of the GIT and they secrete alkaline mucous into ducts.
130 duodenal ulcers are not a/w an increased risk of carcinoma in the same location. Esophageal, gastric, and colorectal cancers are frequently identified as ulcerative lesions on endoscopy.
133 Lactase-deficient pts have increased stool osmotic gap, increased breath hydrogen content, and decreased stool pH upon lactose challenge. Bacterial fermentation of lactose produces short-chain fatty acids and excess amounts of hydrogen. Hydrogen acidifies the stool.
135 NF-kB pathway in crohn’s disease by the NOD2 protein is responsible for cytokine production in the immune response to infectious pathogens.
136 Nitrates are transformed to NO at the vascular smooth muscle cell membrane which leads to increased cGMP whicah decrease intracellular calcium concentration , decreasing the activity of myosin light-chain kinase and finally myosin light chain dephosphorylation and smooth muscle relaxation.
138 Nitroglycerin causes venous pooling so decrease in LV volume, which is decreased cardiac preload, cardiac work and myocardial oxygen demand on the heart that has angina.
139 Isosorbide mononitrate is 100% bioavailable when taken by the oral route.
140 headaches and cutaneous flushing are common side effects of all nitrates.
141 nitrates can cause reflex tachycardia( increase in myocardial oxygen demand), which can be inhibited by beta 1 blockers.
142 pts taking daily maintenance nitrates need to have a nitrate-free period every day to avoid tolerance to the drug.
143 Tuberoinfundibular pathway is responsible for the dopamine that mediates the prolactin secretion. Inhibition of this pathway causes hyperprolactinemia.
145 Nifedipoine causes peripheral vasodilation which may result in reflex tachycardia. Therefore this antihypertensive drug is useful for pts with bradycardia. B1 blocks delay AV conduction increasing PR interval along with Class IV antiarrhythmics.
146 Calcium channel blockers, specifically Nimodipine, can be used to assist in the prevention of cerebral vascular spasm following SAH
147 Hyperkalemia is usually found in acute digoxin toxicity. Calcium gluconate should be avoided in digitalils intoxication.
148 digoxin leads to inhibition of Na K+ ATPase leading to AV nodal blockade (incresed diastolic filling time for greater contraction) and increased contractility from increased intracellular calcium.
149 phosphodiesterase inhibitors lead to increased cardiac contractililty via increased intracellular cAMP concentration. In vascular smooth muscle, increases in cAMP cause vasodilation, a well known side effect of phosphodiesterase inhibitors which can occasionally limit their use in hypotensive pts.
151 ACEi’s along with ARB’s have shown to decrease the progression of diabetic nephropathy. Microalbuminuria is defined as urine albumin loss between 30 and 300mg/day and is indicative of diabetic nephropathy in diabetic pts.
153 Verapamil causes constipation and gingival hyperplasia and bradycardia as well as first, second or third degree AV nodal block.
154 Amlodipine a caclium channel blocker antihypertensive that causes flushing and peripheral edema.Calcium channel blocks cause fluhing.
155 Digoxin increases cardiac contractility by blocking the Na-K-ATPase in cardiac myocytes leading to an increased intracellular calcium concentration, and it will decrease AV nodal conduction by a mechanism of increased parasympathetic tone. Digoxin is second line treatment for atrial fibrillation with rapid ventricular response.
156 digoxin toxicity is manifested as changes in color vision and anorexia. Digoxin toxicity can cause ventricular dysrhythmias, headache, fatigue and confusion.
159 class IB antiarrhythmics have the shortest dissociation time, bind less avidly to the non-resting sodium channels, and are therefore most selective for rapidly and frequently depolarizing cells. Examples of these drugs are lidocaine, mexiletine and tocainide. These drugs have the effect of shortening the length of the action potential and phase 3 repolarization, with little effect on phase 0 depolarization
160 The cutaneous flushing a/w niacin is mediated by prostaglandins and can be prevented with aspirin pre-treatment. Capsaicin reduces pain by decresing the lvl of substance P in the peripheral nervous system.
161 Concomitant administration of drugs that inhibit statin metabolism (e.g macrolides) is a/w increased incidence of statin-induced myopathy and rhabdomyolysis. Acute renal failure is a possible sequela of rhabdomyolysis.
162 Niacin causes vasodilation and also causes insulin resistance and oftentimes necessitates an increase in diabetes medications.
163 cholestyramine is contraindicated in hypertriglyceridemia.
164 Risk of gallstone formation in cholestyramine and gemfibrozil is due to increased cholesterol excretion by the liver, increase in the cholesterol content of the bile.
166 Fibrates and niacin are most effective in the treatment of hypertriglylceridemia. Statin and ezetimibe are most effective in the treatment of hypercholesterolemeia. Niacin can increase HDL levels. Fibrates work by activating peroxisome proliferator-activated receptor alpha (PPAR-alpha). Niacin decreses the synthesis of hepatic triglycerides and VLDL.
167 Niacin toxicity includes vasodilation, hyperglycemia, hyperuricemia/gout and hepatitis.
168 Inhaled corticosteroids (flunisolide) therapy should be instructed about oral rinsing to prevent oropharyngeal candidiasis.
169 persistent bronchial asthma shows hyperinflated lungs, airway mucus plugging and cellular infiltration of the bronchial wall. Corticosteroids over long term would have prevented this effect. Fluticasone is a corticosteroid.
171 Zafirlukast and montelulkast are LTD4 receptor antagonists.
172 Acute theophylline intoxication results in abdominal pain, vomiting, diarrhea, cardiac arrhythmias and seizures.
174 First gen antihistamines are hydroxyzine, promethazine, chlorpheniramine and diphenhydramine and so have antimuscarinic effects. Second gen antihistamines like fexofenadine doesn’t have antimuscarinic effects and are minimally sedative.
175 antimuscarinic and antihistamines with antimuscarinic action (1st gen antihistamines) are most effective for motion sickness).
179 Sinus bradycardia and ST elevation in leads II, III and aVF is characteristic of RCA occlusion.
181 concentric hypertrophy is caused by long standing hypertension. concentric hypertrophy thickens ventricular walls with decreased LV cavity size. MR results in dilated left ventricular hypertrophy Atrial septal defect results in dilated right ventricular hypertrophy
182 both ventricular hypertrophy and volume overload cause release of both ANP and BNP from the ventricular myocytes to facilitate natriuresis and diuresis.
185 heart failure cells indicate that episodes of pulmonary congestion and edema associated with chronic left-sided heart failure. hemosiderin-laden macrophages in pulmonary alveoli indicates chronic elevation of pulmonary capillary hydrostatic pressures, which is result of left-sided heart failure.
188 down syndrome: endocardial cushion defects due of lack of migration of neural crest cells (ostium primum ASD, regurgitnat AV valves) Digeorge syndrome: tetralogy of Fallot and aortic arch abnormalities and Truncus arteriosus Friedrich’s ataxia – hypertrophic cardiomyopathy marfan syndrom: cystic medial necrosis of the aorta Tuberous sclerosis: valvular obstruction due to cardiac rhabdomyomas Turners syndrome: coarctation of aorta
191 Xanthelesma —diabetes and hypercholesterolemia.
192 Acute plaque change of coronary artery disease results in acute myocardial ischemia, which gives rise to ventricular fibrillation. Cardiac arrhythmia is the mcc of death in Myocardial infarction pts.
197 Fat embolism syndrom: respiratory distress, diffuse neurological impairment (confusion) and upper body petechial rash due to thrombocytopenia within days of severe long bone fractures. Fat emboli stains black with osmium tetroxide.
202 formaen ovale is patent in 20-30% of normal adults. It remains patent when right atrial pressure is higher that the left atrial pressure, producing a right to left shunt.
205 Squatting in Tetralogy of Fallot increases systemic vascular resistance, which increases pulmonary blood flow by decreasing the right to left shunt
207 Menotropin (human menopausal gonatotropin) acts like FSH and leads to the formation of a dominant ovarian follicle. Ovulation is then induced by administration of a large dose of hCG, which stimulates the LH surge.
209 Leuprolide is a GnRH agonist that causes first a transient condordant increase, then a concordant decrease in both testosterone and DHT levels. Finasteride causes a discordant decrease in DHT level.
210 Prolactin suppresses GnRH, which causes decreased libido, amenorrhea and infertility.
211 More thatn 10% increase in urine osmolality following administration of vasopressin during a water deprivation test suggests central DI. A urine osmolality increase above 50% is strongly suggestive of comple central DI.
212 psychogenic polydipsia –demonstrates a significant increase in urine osmolality in the water deprivation test. Pts will have low serum sodium levels. Restriction of water intake normalizes urine output in pts with primary polydipsia.
218 Prolacting suppresses GnRH release leading to hypogonadism, anovulation and amenorrhea. Prolonged hypogonadism (low estrogen) causes bone loss. Vaginal dryness is also caused due to low estrogen.
220 Sheehan syndrome. Estrogen during pregnancy can enlarge the pituitary gland and hypotension can cause pituitary gland to undergo ischemic necrosis. This results in panhypopituitarism, including prolactin.
221 craniopharyngioma — Solid, cystic and calicified. Tumor arising from the Rathke’s pouch. Symptoms include headaches, visual field defects and hypopituitarism. Compression of the pituitary stock by craniopharyngioma leads to hyperprolactinemia by loss of dopaminergic inhibition.
222 Risperidone is an antipyschotic that is a dopamine antagonist which causes hyperprolactinemia that causes hypogonadism and amenorrhea.
223 Hyperprolactinemia causes hypogonadism, which leads to low estrogen , which leads to osteoporosis risk.
224 GH increases the linear growth by stimulating the production of IGF-1 from the liver.
226 SIADH is characterized by concentrated urine, low plasma osmolality, increased urinary sodium since excess body water suppresses renin-aldosterone axis, causing low aldosterone causing salt wasting via the urine. These pts have NORMAL total body volume. Hypothyroidism and hypocortisolim should be ruled out before the diagnosis of SIADH is made in real practice.
227 AR is heard best at the left sternal border with pt leaning forward and at end expiration.
228 microemboli from valvular vegetations in infective endocarditis (subacute bacterial endocarditis) are the mcc of subungual splinter hemorrhages. possible can detect new-onset regurgitant murmur via cardiac auscultation.
229 Acute, diffuse, proliferative glomerulonephritis aka post streptococcal glomerulonephritis, secondary to circulating immune complexes may complicate Bacterial endocarditis and result in acute renal insufficiency.
232 Mitral stenosis is a diastolic rumbling murmur. Fibrosis of valve leaflets in chronic rheumatic heart disease following acute rheumatic fever is the most common cause of mitral stenosis.
239 Most likey cause of death in acute rheumatic fever is myocarditis. Mitral stenois afer acute rheumatic fever requires yesr or decades to develop
240 Rheumatic fever also leads to formation of granulomas known as interstitial myocardial granulomas.
242 pulmonary vascular congestion and decrease in MAP present in pts with aortic stenosis.
243 The intensity of AS murmur is proportional to the magnitude of left ventricle-to-aorta pressure gradient during systole.
244 atrial fibrillation causes loss of conduction of atrial contraction to ventricular filling can reduce left ventricular preload and thus cardiac output to cause systemic hypotension. Acute atrial fibrillation also increase steady state pulmonary venous pressures sufficiently to cause pulmonary edema
245 Vol in = A1*v1 = Vol out = A2 * v2 Total flow = flow velocity * cross sectional area= constant.
247 Buspirone has minimal hypnotic effects. Its an agonist of 5HT1A receptor and is a safe and effective treatment for generalilzed anxiety disorder.
249 valproate to treat absence seizures along with tonic-clonic seizures.
251 Primidone is metabolized to phenobarbital and phenylethylmalonamid (PEMA), so thus increses blood phenobarbital levels.
252 Holoprosencephaly is an eg of malformation. Amniotic band syndrome is an eg of disruption (secondary destruction of a previoulsy well-formed tissue or organ). Congenital hip dislocation, clubbed feet and flat facies (potter syndrome) are examples of deformations (secondary to extrinsic compression). Potter syndrome is a alos an example of a sequence.
253 CEA level is a sensitive indicator of colorectal cancer recurrence.
258 Polycyystic ovarian syndrome pts are at risk of getting endometrial adenoarcinoma and diabetes mellitus type II.
260 vit b6 increases the peripheral metabolism of levodopa, which decreases its effectiveness.
261 antimuscarinics are usually preferred in pts with medication-induced parkinsonism.
262 behavioral changes can worsen with the addition of carbidopa to levodopa regimen ( like anxiety and agitation) since theres more DA now.
265 COMT are present in the periphery and degrade dopamine.
270 sporothrix schenkii — transmitted by a thorn prick. Manifests with nodules that spread along lymphatics.
271 Amphotericin B and Nystatin depend on the amount of ergosterol incorporated into fungal cell membranes. Flucytosine competitvely inhibits RNA synthesis in fungal cells. Capsofungin inhibits glucan component of the fungal cell wall.
273 Amphotericin B binds to ergosterol of fungal membranes and also binds cholesterol causing toxicity in human tissues. causes nephrotoxicity, hypokalemia and hypomagnesemia.
274 amphotericin B is the doc for Mucormycosis. It causes renal toxicity and causes hypokalemia and hypomagnesemia dude to increase in distal tubular membrane permeability.
275 Amphotericin B causes nephrotoxicity. Causes both a decrease in GFR and direct toxic effects on the tubular epithelium. Hypokalemia and hypomagnesemia are common due to an increase in the membrane permeability of the distal tubule. ECG finds due to hypokalemia inlcude T-wave flattening, ST-depression, prominent U waves and premature atrial and ventricular contractions. Profound hypokalemia can cause ventricular tachycardia or fibrillation.
279 Cricopharyngeal muscle dysfunction is a condition caused by diminished relaxation of pharyngeal muscles during swallowing. The subsequently increased intraluminal pressure in the oropharynx causes the mucosa to herniate through the wall at a point of muscle weakness, forming a Zenker diverticulum. pts present with oropharyngeal dysphagia, coughing, choking, and recurrent aspiration.
283 Three main causes of HIV-associated esophagitis: Candida, cytomegalovirus and herpes virus. Candida shows patches of adherent, grey/white pseudomembranes on erythematous mucosa. Hsv-1 shows small vesicles that evolve into typical punched out ulcers and eosinophilic intranulcear inclusions (cowdry type A) in mutlinuclear squamous cells at the margin of ulcers. CMV shows linear ulceration and both intranuclear and cytoplasmic inclusions
286 silent GERD presents with nocturnal cough, sore throat and dysphasia even thought they don’t feel heartburn. Gastroesophageal junction incompetence causes GERD. Transient LES relaxations and hypotensive LES. Characteris histologic features include basal zone hyperplasia, elongation of lamina propria papillae and inflammatory cells (eosinophils, neutrophils and lymphocytes).
295 pathologic atrophy occurs due to decreased physical workload, loss of innervation, decreased blood supply, inadequate nutrition, absent endocrine stimulation, aging or pressure.
296 dystrophic calcification is a hallmark of preceding cell injury and necrosis.
297 cytochrome C is a mitochondrial enzyme that activates caspases and indirectly bring aout cell death though intrinsic pathway apoptosis.
300 lipofuscin — product of free radical injury and lipid peroxidation.
301 IFN-gamma secreted by T-lymphocytes contributes to granuloma formation.
302 Lung abscess is via the release of lysosomal enzymes by neutrophils and macrophages.
303 Superior mesenteric artery syndrome: when transverse portion of the duodenum is trapped between the SMA and the aorta.
304 Histamine, ach and gastrin increase gastric acid secretion, while PGE2 inhibits it. Gastrin not only facilitates Hcl secretion, but it also has a trophic effect on parietal cells, causing proliferation and hyperplasia of these cells. There is excess gastrin release in Zollinger ellison syndrome.
306 gastric hypersecretion is a common occurrence in systemic mastocytosis.
308 Pathogenesis of Meniere’s disease in related to an increased volume and pressure and endolymph in the vestibular apparatus. Triad is tinnitus, vertigo and sensorineural hearing loss.
309 Carcionoids are the most common appendiceal tumors. Symptoms of carcinoid syndrome includes flushing, diarrhea and wheezing and syncope (due to low blood pressure). carcinoid syndrome can cause right sided valvular heart disease. Treatment for carcinoid syndrome is octreotide, which inhibits the secretion of hormones and hormone-like substances. Also inhibits secretory diarrhea in VIPomas (pancreatic endocrine tumors).
311 Vit C deficiency in malnourished individuals like the homeless, alcoholics and drug users. have perifollicular hemorrhages, easy bruising and gum disease and in children, have bony deformities and subperiosteal hemorrhages.
314 p450 microsomal oxidase system usually detoxifies CCl4, but in CCl4 poisoning, it produces free radicals (lipid peroxidation).
317 extrahepatic biliary atresia is a congenital obstruction of extrahepatic bile ducts. Has a cholestatic picture of acholic stools and dark urine, and has increases levles of conjugated bilirubin, alkaline phosphatase and gamma-glutamyl transferase. Shows intrahepatic bile ductule proliferation, portal tract edema and fibrosis and parenchymal cholestasis
319 Small intestinal and colonic atresias occur due to vascular accident in utero. If the superior mesenteric artery is osbstructed, so called apple peel atresias occur.
320 Imperforate anus is most commonly a/w genitourinary tract malformations.
322 Omphalomesenteric (vitelline) duct normally obliterates during 7th week of embryonic development. Both enterocysts and Meckel diverticulum are result of obliteration faillure of the omphalomesenteric duct. The vitelline duct cyst forms when the peripheral portions of the duct obliterate, but the central part is left. This cyst is connected by a fibrous band to the ileum and the umbilicus.
323 Sudan III dye is used to screen for malabsorption by looming at the fat in stools. >7g/day of excreted fat is diagnostic of malabsorption.
325 dermatitis herpetiformis is associated with celiac disease.
326 IgA antibodies in celiac disease alsong antibodies to gliadin and anti-endomysial and anti-reticulin. Small intestinal biopsy best for celiac disease diagnosis.
329 99mmTc-pertechnetate scan detects the presence of gastric mucosa. This is present in Meckel’s diverticululm that is due to the failed process of obliteration of the omphalomesenteric duct.
330 Neural crest cells are present in the wall of proximal colon at 8th week of gestation and in the rectum by 12th week. Failure of migration into rectum results in Hirschprung’s disease.
336 Tumor penetration of the bladder wall is the major determinant of prognosis of bladder cell carcinomas. The staging of this tumor type depends on the degree of its invasion into the bladder wall and adjacent tissues.
337 polyhydrominios due to increased fetal urination include high cardiac output due to anemia or twin-twin transfusion syndrome.
338 Most exogenous injuries, including a brown recluse spider bite are a/w coagulative necrosis. Organ ischemia is the classic example of coagulative necrosis. Cell cytoplasm becomes eosinophilic due to protein denaturation. The nucles shrinks and there is chromatin clumping (pyknosis), fragmentation (karyorrhexis and eventually, lysis.
339 Cystic hygroma and lymphedema manifests in neonates of Turner syndrome.
342 AFP is synthesized by the fetal liver, GI tract and yolk sac. The most common cause of elevated AFP lvls is dating error (underestimation of gestatational age) which can be confirmed by fetal USG. Increased AFP levels is also a/w neural tube defects, anterior abdominal wall defects (omphalocele, gastrochisis) and multiple gestation. Estriol reflects both placental and fetal function. Hcg increased in multiple gestation, hydatidiform mole and choriocarcinoma.
344 In Fragile X syndrome, cytogenetic studies show a small gap near the tip of the long arm of the X chromosome.
345 Li-Fraumeni syndrome ppl who have a mutation of p53 gene are at risk of several cancers.
346 Ristocetin aggregation test is used to measure vWF-dependent platelet aggregation. Ristocetin activates Gp Ib-IX receptors on platelets and makes them available for vWF binding. When the vWF level is decreased, there is poor platelet aggregation in the presence of Ristocetin. Decreased levels of vWF can also lead to functional deficiency of factor VIII since it binds to it and thus increases its half life. Desmopressin (DDAVP) is used to treat vWd.
349 Z drugs have lower risk of tolerance and dependence.
350 Benzos substitute for the action of alcohol on GABA receptors and are indicated for the treatment of alcohol withdrawal. Long acting benzos likes chlordiazepoxide and diazepam are first line medications, whereas short acting benzos (lorazepam, oxazepam) are preferred in pts with advanced liver dysfunction.
353 Benzodiazepines are first line treatment for management of status epilepticus and phenytoin is administered simultaenously to prevent recurrence of seizures.
355 Sodium valproate is the drug of choice for myoclonic seizures. Phenytoin for tonic-clonic. Carbamezapine for both simple and complex partial seizures.
359 Chlramphenicol can lead to both dose-dependent (reversible) and dose-independent (often irreversible) pancytopenia.
361 snRNPs are synthesized by RNA poly II in the nucleus. They help remove introns from the RNA transcript and are thus necessary for synthesis of mRNA.
362 Gilbert’s seen in pts with no apparent liver disease who have mild unconjugated hyperbilirubinemia that appears provoked by on the of the triggers like hemolysis, fasting, physical exertion, febrile illness, stress and fatigue.
363 criggler najjar – absent liver conjugation enzymes.
364 Cholestasis can arise secondary to hepatocellular dysfunction or biliary obstruction. Characterized by deposition of bile pigment within the heaptic parenchyma and the presence of green-brown plugs in the dialted bile canaliculi.Cholestasis can result in malabsorption and nutritional deficiencies of teh fat-soluble vitamins, leading to conditions such as osteomalacia (which is frequently a/w a deficiency of the fat-soluble vitamin D.
365 Serum sickness-like symptoms include fever, rash, malaise, pruritus, lymphadenopathy and joint pain. These symptoms can be found in acute hepatitis B infection. Alkaline phosphatase in raised in acute viral hepatitis as well as in obstructive jaundice.
367 In hepatitis B, you have fine cytoplasmic protein granules composed of HbsAg spheres and tubules. Eosinophilic appearance known as ground glass
370 alcohol-induced hepatic steatosis is via decrease in fatty acid oxidation secondary to excess NADH production by alochol dehydrogenase and acetaldehyde dehydrogenase.
371 Hep A virus can be inactivated with water chlorination, bleach (1:100 dilution), formalin, ultraviolet irradiation, or boiling to 85c for one minute.
372 Hep A infection via contaminated water or food, with raw or steamed shellfish.
373 Hep A is most often silent or subclinical in children but can aslo present as an acute, self-limited illness characterized by jaundice, malaise, fatigue anorexia, nausea, vomiting and RUQ pain.
374 Hep B viral genome replication sequence: dsDNA—>template +ssRNA–> progeny dsDNA.
375 Presence of viral HBsAg and HBcAg on the cell surface stimulates the host’s cytotoxic CD8+ T lymphocytes to destroy the infected hepatocytes.
376 Hep B has RNA dependent DNA polymerase activity. Reverse transcriptase DNA polymerase that creates an intermediate + single stranded RNA template.
386 HBV primarily spread via blood, but the virus can also spread by exposure to semen, saliva, sweat, tears, breast milk and pathologic effusions. IV drug abusers, homosexual men, needle-stick accidents, pts on dialysis.
387 HBsAg is the component of hepatitis B virus envelope, HBsAg is a noninfective glycoprotein that forms spheres and tubules 22nm in diameter.
388 Hep C is genetically unstable because it lacks proofreading 3′—>5′ exonuclease activity in its RNA polymerase and its envelope glycoprotein contains a hypervariable region prone to frequent genetic mutation.
389 Hepatitis C causes stable chronic hepatitis, followed closely by chronic hepatitis progressing to cirrhosis.
391 Vitamin C plays a role in iron absorption.
394 Bronze diabetes in hemachromatosis is of triad skin hyperpigmentation, diabetes mellitus and pigment cirrhosis with hepatomegaly.
395 Crucial site for HFE expression is teh basolateral surface of the epithelial cells of the small intestine crypts, where it complexes with B2-microglobulin and then binds to the transferrin receptor to regulate endocytosis of the transferrin/iron complex into cells. Due to mutation, there is unregulated expression of the iron uptake proteins and an excessive amount of iron is absorbed gastrointestinally. Hemochromatosis has a risk for development of cirrhosis and HCC.
399 PAS postive staining granules in globules in the liver are the alpha 1 antitrypsin proteins (unsecreted A1AT in the periportal hepatocytes), which are responsible for the destruction of alveolar walls in the lungs resulting in panacinar emphysema.
400 A history of neonatal hepatitis with cholestasis should heighten suspicion for A1AT deficiency.
401 Primary biliary sclerosis can have pruritus, fatigue, hepatosplenomegaly and xanthomatous lesions in the eyelid or in the skin and tendons. As teh disease progresses, jaundice, steatorrhea, portal hypertension, and osteopenia may develop. Elevated alkaline phosphatase levels and cholesterol and serum IgM is seen. Antimitochondrial antibodies are also seen. Associated conditions include Sjogren’s , raynaud’s syndrome, scleroderma, hypothyroidism and celiac disease
406 Th1 increases the production of IL-2 which releases gamma interferon and TNF. Non caseating granulomas are characteristic of crohn’s disease
408 There is an increased risk of cholangiocarcinoma in crohn’s pts and associated with primary sclerosing cholangitis. Also associated with strictures, fistulas, pyoderma gangrenosum and erythema nodosum, arthritis and ankylosing spondylitis. Formation of oxalate stones due to malabsorption and b12 and folate deficiencies. lipids bind to calcium and are excreted in feces. Oxalate is supposed to bind to calcium but is left behind which is absorbed and thus form stones.
409 Transmural inflammation explains the two complications of Crohn’s disease: strictures and fistulas.
410 Use Flat plain X-ray to see diagnose the toxic megacolon of the ulcerative colitis.
415 Colonic diverticula develop due to increase in intraluminal pressure from straining during a bowel movement. Seen in ppl 60+ yrs (chronic constipation is a risk factor). They are pulsion by mechanism and false by structure just as Zencker diverticulum. They only composed of mucosa and submucosa. Most common site is the sigmoid colon.
419 Hydrocele occurs when there is a connection between the scrotum and abdominal cavity that only allows for the leakage of fluid, whereas, a hernia occurs when the opening allows the protrusion of abdominal organs along the inguinal canala. Both Hydrocele and indirect inguinal hernia are formed by the incomplete obliteration of the processus vaginalis.
424 Most common location of intestinal carcionoids is the ileum and also frequently appear in the appendix and the rectum.
426 fecaliths are responsible for lumen obstruction of appendix that causes appendicits.
427 Non-neoplastic polyps includes lymphoid polyps, hamartamatous, hyperplastic and inflammatory. Adenomatous polyps contain dysplastic mucosal cells and can transform into adenocarcinoma. Villous adenomas are more likely to progress to adenocarcinoma than tubular adenomas.
430 Villous adenomas have cauliflower-like-projections. Tubular adenomas are dysplastic colonic mucosal cells that form tubular-shaped glands. Villous adenomas are dysplatic epithelial cells that form villi-like projections that extend from the polyp surface down to the stroma. Villous adenomas can cause bleeding, secretory diarrhea and partial intestinal obstruction.
432 left sided colon cancer – obstruction so abdominal pain, distension and nausea. Right sided colon cancer – iron deficiency anemia from blood loss and present with anorexia, malaise and weight loss.
440 Gallstones and alcoholism are the most common causes of acute pancreatitis. Other factors include ERCP (endoscopic retrograde cholangiopancreatography), hypertriglyceridemia, drugs, infections and hypercalcemia.
441 abnormal activation of trypsin within the pancreas is a central event in the pathogenesis of acute necrotizing pancreatitis.
443 vascular reaction to endothelial and intimal injury is intimal hyperplasia and fibrosis, predominantly mediated by reactive smooth muscle cells that migrate from the media to the intima.
445 atherosclerotic plaques develop predominantly in large elastic arteries (aorta, carotid and iliac arteries) and in large or medium sizes muscular arteries.
446 Pathogenesis of atherosclerotic plaques: exposure of subendothelial collagen promotes platelet adhesion, aggregation and release of factors that promote smooth muscle cells from media into the intima, as well as SMC proliferation. These factors include PDGF and TGF-B. PDGF is chemotactic and mitogenic for SMC. TGF-B is chemotactic for SMC.
447 In atherosclerosis, high intraplaque activity of metalloproteinases would predispose the pt to MI. Procollagen peptidases is deficient in Ehler’s danlos syndrome.
447 the likelihood of acute plaque change (especially rupture) producing an acute coronary syndrome via superimposed thrombosis and/or thromboembolism is most related to plaque stability. Plaque stability depends significantly on mechanical strength of the fibrous cap. Inflammatory macrophages in the intima may reduce plaque stability by secreting metalloproteinases, which degrade collagen.
448 Claudication : intermittent muscle pain reproducibly caused by exercise and relieved by a brief period of rest. Caused by atherosclerosis of larger arteries like external iliac and femoral. Atheromas are lipid-filled intimal plaques that bulge into the arterial lumen
453 Renal artery stenois due to atheromatous plaque causes renin secretion and thus causing hypertension. This is lesion is frequently present in males and patients with diabetes mellitus, and incidence increases with age. The stenois also causes renal atrophy due to oxygen and nutrient deprivation.
456 Isolated systolic hypertension is age-related decrease in the compliance (increased stiffness) of the aorta.
459 Wegerner’s granulomatosis – C-ANCA (anti neutrophilic cytoplasmic antibodies. Necrotizing vasculitis of the upper and lower respiratory tract ( causing nasal ulcerations, sinusitis, hemoptysis) and rapidly progressive glomerulonephritis. C-ANCAs target neutrophil proteinase 3.
465 Inherited causes of hypercoagulability should be considered in pts younger than age 50. Factor V Leiden mutation, which causes factor Va resistance to inactivation by activated protecin C. This can lead to hypercoagulable state and thus cases of atypical venous thromboses.
468 characteristic tram-track calcifications on skull radiographs — Sturge weber syndrome. Cerebellar hemanigioblastoma in association with congenital cysts of the kidneys, liver and/or pancreas is highly suggestive of Von-Hippel-Lindau disease.
475 Migratory thrombophlebitis is due to cancer due to hypercoagulability. Migratory superficial thrombophlebitis is Trousseau’s syndrome
476 Significant mismatched defect on ventilation-perfusion scan is a specific finding for a pulmonary embolism caused by deep vein thrombosis.
479 lamellar bodies of type II pneumocytes contain dipalmitoyl phosphatidylcholine- major components of pulmonary surfactant.
480 Epithelial cilia persist upto the end of the respiratory bronchioles and is the last to disappear as the epithelium changes along the respiratory tube.
481 Medium and small-sized bronchi greater than 2mm in diameter provide the greatest summated frictional resistance to airflow in normal airways. Airway generations 2-5 (including the segmental bronchi) normally have a higher regional resistance thatn the upper respiratory tract, accounting for the curve’s parabolic shape of the curve.
482 The phospholipid content of the amniotic fluid is determined in order to tcheck for the fetal lung maturity.
484 elastase is a natural protease contained in macrophage lysosomes and in large, azurophil granules of neutrophils. Excess elastase activity in lung acini is thought to be a major factor in the development of centriacinar and panacinar emphysema.
486 Interstitial and alveolar edema and exudate in ARDS result from increased pulmonary capillary permeability. The result is decrease in lung compliance, and increase in the work of breathing, a worsened V/Q mismatching. Pulmonary capillary wedge pressure is typically normal.
490 Rupture of apical subpleural blebs is the most common cause of primary spontaneous pneumothorax. The blebs may arise due to distal acinar(paraseptal) emphysema. other types of emphysema may predispose to a secondary spontaneous pneumothorax. Tall, thin, young adult males are most commonly affected.
494 Cell body rounding, peripheral displacement of the nuclei and dispersion of Nissl substance to the periphery incdicates axonal reaction after injury.
495 Transtentorial (uncal) herniation is a complication of an ipsilateral mass lesion, such as a hemorrhage or brain tumor. First sign of uncal herniation is a fixed and dilated pupil on the side of the lesion. Ipsilateral paralysis of oculomotor muscles, contralateral or ipsilateral hemiparesis, and contralateral homonymous hemianopsia with macular sparing may also occur.
496 Folic acid is a vitamin. Neural tube defects could be prevented by vitamin supplementation (includes folic acid) to the mother.
497 saccular aneurysms = berry aneurysms.
498 Hypertension is the most common overall cause of intraparenchymal hemorrhage, usually through the formation of small Charcot-Bouchard pseudoaneurysms in the small arterioles that penetrate the basal ganglia and thalami. This should be contrasted with rutpure of a saccular aneurysm which typically presents with subarachnoid hemorrhage.
500 Pts who survived subarachnoid hemorrhage develop secondary arterial vasospamsm
508 Phenytoin is useful in treating tonic-clonic and psychomotor seizures as well as for seizure prophylaxis after head trauma and before neurosurgery. Phenytoin’s undesirable cosmetic effects (hirsutism, coarsening of facial features, aceneiform skin rash, and gingival hypertrophy), limits its use. It is also a/w generalized lymphadenopathy (pseudolymphoma).
510 Akathisia is a movement disorder characterized by inner restlessness an an inability to sit or stand in one position (restless legg syndrome). Acute dystonia defined by twisting involuntary movements and abnormal postures and occurs within 5 days of anti-psychotic use. Tardive dyskinesia is involuntary perioral movements such as biting, chewing, grimacing, and tongue protrusions. arisese usually between four months and four years of treatment.
513 Mesolimbic-mesocortical pathway regulates behavior and is hyperactive in schizophrenia. Neuroleptics block dopamine in this pathway. Nigrostriatal pathway (neurons project from substantia nigra to the caudate nucleus and putamen) and they regulate coordination of voluntary movements. DA inhibits Ach release in this pathway. Loss of DA neurons in this pathway increase Ach.High potency antipsychotics cause dopamine antagonism in this pathway leading to drug-induced parkinsonism
514 High potency antipsychotics like haloperidol, fluphenazine and pimozide more likely cause extrapyramidal symptoms and less likely cause anticholinergic and antihistamine side effects. Low potency drugs like chlorpromazine and thioridazine more likely cause anticholinergic and anti histamine side effects.
515 Nigrostriatal pathway primarily regulates coordination of voluntary movements. In this pathway dopamine inhibits the release of acetylcholine. High potency antipyschotics act primarily on D2 receptors of the mesolimbic-mesocortical pathway but at the same time block dopamine in the nigrostriatal pathway as well. This cause subsequent increase in acetylcholine, leading to motor disorders such as Parkinsonism and acute dystonias
518 antidepressants used to treat depressifve phase of bipolar disorder can precipitate mania .eg: TCA’s
519 NSAIDs, thiazide diuretics and ACE inhibitors increase lithium levels and elevate the risk of lithium toxicity. Hemodialysis is the most effective way of acutely reducing the blood lithium levels.
520 Lithium can cause nephrogenic diabetes insipidus and hypothyroidism. It is also a teratogenic and causes Ebstein’s anomaly.
524 Chronic bronchitis: Thickened bronchial walls, neutrophilic infiltration, mucous gland enlargement, and patchy squamous metaplasia of the bronchial mucosa.
525 Smoking is associated with chronic bronchitis. 3 consecutive months of sputum production for the last 2 consecutive years. Reid index –normal is 0.4 submucosal gland thickness/ brochial wall thickness between the ciliated pseudostratified columnar epithelium and the perichondrium
527 extrinsic allergic asthma has eosinophils and charcot-leyden crystals. Eosinophils are recruited and activated by IL-5.
531 Lobar pneumonia stages: Congestion, red hepatization, gray hepatization (rbc’s disintegrate) and resolution.
535 chronic rejection of lung transplants can affect teh small bronchioli producing the obstructive lung disease known as bronchiolitis oblliterans.
536 Particle 10-15um are trapped in the upper respiratory tract. Particles 2.5-10um in size enter the trachea and bronchi and are cleared by mucociliary transport. Finest particles (<2um) reach the terminal bronchioli and alveoli and are phagocytized by macrophages. These macrophages then release PDGF and IGF which stimulate fibroblasts to prolerate and produce collagen in the subsequent inflammatory process of Pneumoconiosis.
537 Wiskott-Aldrich triad of eczema, thrombocytopenia and combine B and T cell deficiency. Thrombocytopenia present at birth and repeated infections by encapsulated organisms
538 Leukocyte adhesion deficiency results from the AR absence of CD18. This leads to inability to synthesize integrins. Integrins are necessary for leukocytes to exit the bloodstream, and sequelae of this illness inclue recurrent skin infections WITHOUT pus formation, delayed detachment of the umbilical cord and poor wound healing.
542 Failure to acidify lysosomes would lead to deficient expression of MHC class II bound to foreign antigen and subsequent lack of interaction between APCs and T-cells.
545 Clinical picture of fetus of Erythroblastosis fetalis involves severe anemia, hepatosplenomegaly, jaundice (possibly leading to kernicterus) and possible fetal demise/death in an infant. Also find nucleated erythrocytes and many areas of extramedullary hematopoiesis in many tissues.
548 Corticosteroids increase liver protein synthesis (enzymes for glycogen synthesis and gluoconeogenesis), which results in hyperglycemia.
549 Acute effects of corticosteroids on CBC include increased neutrophil count and decreased lymphocyte, monocyte, basophil and eosinophil counts. This increase in neutrophil count results from demargination of neutrophils previously attached to the vessel wall.
550 Cortisol stimulates surfactant production. Corticosteroids are administered to mothers who are at risk of having a premature delivery with fetal lung immaturity.
551 Cortisol has permissive effects. It increases the vascular and bronchial smooth muscle reactivity to catecholamines.
554 adenocarcinomas are most common lung cancer. common subtype in women and non smokers. consists of tumor cells that form glandular or papillary structures.
554 adenocarcinoma is the most common lung cancer in the general population. It is also the most common subtype in women and non-smokers.
555 neuroendocrine markers include neuron specific enolase, chromogranin and synaptophysin. small cell carcinoma arises from the primitive cells fo the basal layer of bronchial epithelium. It is strongly associated with smoking.
559 Immature cortical T-lymphocytes express both CD4 and CD8 cell surface antigens in addition to a complete TCR or a pro-TCR. Undergo positive selection in thymic cortex and negative selection in the thymic medulla.
560 IgA protease is produced by N.menigitidis and N.gonorrhea.
561 second most common cause of SCID is AR deficiency of adenosine deaminase. Toxic levels of adenosine accumulate within lymphocytes leading to lymphocyte cell death and resultant cellular and humoral immune deficiency. Treatment presently being researched using retroviral vectors to infect patient stem cells with teh gene coding for ADA.
564 bronchoalveolar carcinoma causes peripheral mucinous gray-white nodules. Arises from alveolar epithelium and is composed of tall, columnar cells that line the alveolar septa without vascular or stromal invasion.
568 Acute rejection time frame is 1-4 weeks follwing transplant.
569 Hyperacute transplant rejection is Type II and acute solid organ transplant rejection is type IV
572 Hypertensive crisis after a wine and cheese party! Think of MAO inhibitor-tyramine crisis.
573 MAO inhibitors are particularly useful in pts with atypical depression (eg, with hyperphagia and weight gain) and treatment resistant depression.
574 TCA’s inhibit presynaptic NT reuptake (causes tremor and insomnia), cardiac fast sodium channels (causing conduction defects, arrhythmias, hypotension, hyperthermia, flushign and dilated pupils), central and peripheral muscarinic Ach receptors, peripheral alpha 1 adernergic receptors causing orthostatic hypotension, and histamine (H1) receptors causing sedation.
575 TCAs are commonly used for treatment of painful diabetic neuropathy. Its anticholinergic effect can cause suprapubic fullness. look at the table of different effects of TCA’s.
576 sertraline is an SSRI
578 Oral contraceptives reduce the risk of non hereditary ovarian cancer and endometrial cancer. Multiparity and breast-feeding also decrease the risk of ovarian cancer. Link of ovarian cancer with conditions associated with ovarian dysfunction, such as infertility, nulliparity, miscarriages and use of clomiphene citrate to induce ovulation.
579 Delayed puberty + anosmia is diagnosis of Kallmann’s syndrome wheres the GnRH secreting neuro fail to migrate from their origin in the olfactory placode. The cause is eithe the mutation of KAL-1 gene or the FGFR-1 gene, which codes for proteins required in this migration.
580 seminiferous tubules are responsible for the secretion of inhibin and they degenerated when exposed to heat as in cryptorchidism
581 Tamoxifen and raloxifene are called selective estrogen receptor modulators (SERMs) because of their tissue-selective estrogen agonist and antagonist properties. Tamoxifen is useful for treatment of osteoporosis and breast cancer. However, it is a/w endometrial hyperplasia, polyps and cancer and thromboemobolic disesae.
582 klinefelter has hypogonadism (damage to seminiferous tubules and legydig cells are damaged as well resulting in low testosterone levels and erectile dysfunction resulting in small firm testes.
583 MIfepristone is an anti-progestin (progesteron antagonist) agent that can be used to terminate early pregnancy. Prostaglandin E1 analogue, misoprostol.
585 Glucagonoma is characteristically present with necrolytic migratory erythema.
586 Jejunal ulcers are common in gastrinomas. Pts complain of diarrhea and abdominal pain.
587 Ataxia Telangiectasia is characterized by triad of cerebellar ataxia, telangiectasias, and increased risk of sinopulmonary infections. AR inheritance and defect is the ATM gene that plays a role in DNA break repair. The immune deficiency manifests as an IgA deficiency and predisposes to infections of upper and lower airways.
589 secretory form of IgA has two immunoglobulin monomers, J chain and secretory component. Its present in saliva, tears, mucus and colostrum.
592 amyloid accumulation in alzheimers in the walls of cerebral arteries causes amyloid angiopathy.
595 Paraneoplastic syndromes occur due to tumor cells producing substances that frequently induce an autoimmune reaction.
596 There are variable degrees of severity even in mitochondrial diseases and this is known as heteroplasmy.
597 The infusion of glucose without thiamine in a pt with chronic thiamine deficiency precipitates encephalopathy.
598 Thiamine is used by pyruvate dehydrogenase, alpha ketoglutarate dehydrogenase and transketolase – an enzyme of the HMP shunt that converts pentoses (derived from glucose) to glyceraldehyde 3P ( an intermediary of glycolysis).
599 Fluid retention, with resultant weight gain and edema, is a common side effect of thiazolidinedione therapy. This excess fluid can exacerbate underlying CHF.
600 Regular insulin is preferred in the initial treatment of diabetic ketoacidosis.
602 PNMT, which is responsible for conversion of NE to epinephrine is under the control of cortisol.
605 Thiazolidinediones bind to peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a receptor that belongs to the steroid and thyroid superfamily of nuclear receptors..Its a transcriptional regulator and exerts its glucose-lowering effect by improving insulin resistance.
606 Acarbose and miglitol are alpha glucosidase inhibitors that inhibit membrane bound disaccharides on the intestinal brush border. They delay the absorption of carbohydrates since they can only be abosorbed in monosaccharide form.
607 Metformin is contraindicated in pts with renal failure, liver dysfunction, CHF, alcoholism and sepsis due to risk of lactic acidosis.
609 depression of the entire hypothalamus-pituitary-adrenal axis by glucocorticoid therapy is the most common cause of adrenal insufficiency.
614 Areas of necrosis and hemorrhage see on gross examination of glioblastoma multiforme. On light microscopy pseudopalisading tumor cells around areas of necrosis are diagnostic.
622 high-dose glucocorticoids are used to control severe Graves’ ophthalmopathy. They are helpful in decreasing the severity of inflammation and decreasing extraocular volume. Remeber that conventional antithyroid drugs dont not improve ophthalmopathy. glucocorticoids reduce the peripheral conversion of T4 to T3 and the inflammatory infiltration responsible for the opthalmopathy.
624 Due to structural similarity, hCG can bind to the TSH receptor, with lower affinity resulting in hyperthyroidism. Increased hCG levels in teratomas that usually occur in testes and ovaries.
625 Amiodarone toxicity includes thyroid dysfunction, corneal micro-deposits, blue-gray skin discoloration, drug-related hepatitis and pulmonary fibrosis.
627 Differences in the bone density curves can best be explained by genetic differences.
628 Risk factors for osteoporosis are smoking, menopause, corticosteroid therapy, physical inactivity, caucasian race (immutable), low body weight and alcohol use.
629 osteoporosis represents loss of total bone mass that results in trabecular thinning. Subperiosteal resorption with cystic degeneration is characterized of hyperparathyroidism. Vit D deficiency result in excesssive unmineralized osteoid resulting in low mineral density. Osteopetrosis is characterized by the persistence of primary, unmineralized spongiosa in the medullary canals.
630 Rickets : Osteoid matrix accumulation around trabeculae. An increase in unmineralized osteoid matrix and widened osteoid seams. Notable features include bowed legs, a rachitic rosary, Harrison’s sulci, craniotabes and growth retardation.
634 cervical dystonia, blepharospasm and writer’s cramp are the most common types of focal dystonia.
637 agranulocytosis is a complication of antithyroid drugs so look at the WBC count.
639 Paget’s disease sx can include bilateral hearing impairment. Paget disease of bone is duet to excessive osteoclastic bone resorption. Osteoclasts in paget’s disease are typically very large and can have upto 100 nuclei. The two most imp factors for osteoclastic differentiation are produced by osteoblast. These are M-CSF(macrophage colony stimulating factor) and RANK-L.
640 RANK/ RANK-ligand interaction is essential in formation and differention of osteoclasts. The over-expression of RANK receptors in hypoestrogenic states causes increased bone resorption due to increased osteoclastic activity. Low estrogen means lower bone mass.
645 Staph epidermidis is catalase positive and coagulase negative and colonized intravenous catheters and prosthetic devices (heart valves, vascular grafts, peritoneal dialysis catheters). Initial aggressive treatment is a must. S.epidermidis are susceptible to vancomycin comined with rifampin or gentamicin, and is resistance to methicillin.
648 Pancoast syndrome is characterized by ipsilateral Horner’s syndrome, rib destruction, atrophy of hand muscles, and pain in the distribution of C8, T1 and T2 nerve roots. Pancoast tumor is aka superior sulcus tumor
656 Spironolactone has anti-androgenic properties and is used for treatment of hirsutism. Other drugs can include antiandrogens like flutamide (inhibits binding to testosterone receptors) and finasteride (5a reductase inhibitor)
658 Finasteride is a 5 alpha reductase inhibitor that suppresses periphearl conversion of testosterone to DHT. It is used for treatment of benign prostatic hyperplasia (BPH) and male baldness.
659 Drugs with high blood/gas partial coefficients are more soluble in the blood and demonstrate slow onset of action and slow equilibration with the brain. Anesthetic tension in blood is not a measure of potency. Potency is defined by MAC value.
661 only leukotreienes (LTc4,d4,e4) and Ach have pharmacologic receptor antagonists that offer therapeutic benefits to allergic asthma.
662 stimulation of vagus nerve branches supplying the lung would cause bronchoconstriction and increased mucus secretion (M3 receptors). These effects increase airway resistance and the work of breathing.
664 Primary ciliary dyskinesia causes male infertility, situs inversus, recurrent sinusitis/otitis and bronchiectasis.
665 Allergic bronchopulmonary aspegillosis (ABPA) due to aspergillus may complicated asthma and can result in transient recurrent pulmonary infiltrates and eventual proximal bronchiectasis.
666 churg strauss– APE (asthma, p-ANCA and eosinophils)
668 asbestosis is associated with calcified pleural plaques and ferruginous bodies silicosis produces eggshell calcification of hilar nodes and birefringent particles surrounded by fibrous tissue on histological exam
670 In silicosis, there may be disruption of macrophage phagolysosomes by internalized silica particles. Macrophage killing of intracellular mycobacteria may be imapaired as a result, causing increased susceptibility of pts with silicosis to pulmonary tuberculosis.
672 Friedrich ataxia – dysfunctional frataxin gene encoded from mutated gene on chromosome 9, which is essential for normal mitochondrial function. Causes degeneration of ascending and descending spinocerebellar tract. Degeneration of dorsal columns and dorsal root ganglia causes loss of position and sensation. Kyphoscoliosis and foot abnormalities (pes cavus – high arch). HOCM and diabetes mellitus also associated.
674 UMN signs include spastic paralysis, hyperreflexia, and an upgoing plantar reflex (babinski sign). Lower motor neuron lesions are from damage to the motor neurons of the anterior horn. Lower motor neuron lesions cause flaccid paralysis, areflexia, atrophy and fasciculation.
675 In ALS you have loss of neurons in anterior horn and degeneration of lateral CST. Loss of neurons in motor nuclei of CN V,IX,X and XII and denervation atrophy (small angular fibers). mutation of copper-zinc superoxide dismutase. Rx is Riluzole that decreases glutamate release. LMN sx: muscle weakness, atrophy and fasciculation. UMN sx: muscle weakness, spasticity, hyperreflexia and pathologic reflexes.
681 loop diuretics produce brisk diuresis. They are commonly used in treating pulmonary edema, venous and pulmonary congestion secondary to congestive heart failure and peripheral edema. Common side effects inlcude hypokalemia, hypomagnesemia and hypocalcemia.
682 carbonic anhydrase inhibitors like acetazolamide are used to relieve intraocular pressure in open-angle and secondary glaucoma.
684 Loop diuretics also stimulate prostaglandin release. By doing this, loop diuretics also increase renal blood flow leading to increased GFR and enhanced drug delivery.
685 Ototoxicity seen in loop diuretics, aminoglycosides, salicylates and cisplatin.
686 spironaolactone is believed to benefit the overall survival of a CHF pt. Aldosterone is known to cause ventricular remodeling leading to cardiac fibrosis.
688 toxicity of aggressive osmotic diuretics causes pulmonary edema.
689 Fenoldopam, a dopamine 1 receptor agonist causes arteriolar dilation and natriuresis leading to decreased systemic vascular resistance and blood pressure reduction. Also improves renal perfusion and maybe beneficial in hypertensive pts with concomitant renal insufficiency.
692 beta blockers inhibit renin angiotensin system causing reduction in all and no change in bradykinin levels.
693 ACE inhibitors cause first dose hypotension which can be exacerbated by thiazides and loop diurections since they cause hypovolemia and hyponatremia which further exacerbates the hypotension and bradycardia. Predisposing risk factors of first-dose hypotension include hyponatremia, hypovolemia secondary to diuretics, low baseline blood pressure, high renin or aldosterone levels, renal impairment and heart failure.
696 ACE inhibitors can exacerbate renal failure in renal artery stenosis pts who are dependent on efferent arteriole constriction to maintain renal perfusion.
698 Sex hormones promote both growth and epiphysial plate closure, hence, precocious puberty may result in a shorter stature, despite an initial growth spurt. Somatomedin C aka IGF-1 does not lead to premature closure of the epiphysis.
704 Bupropion (antidepressant), isoniazid and imipenem (antibiotic)
708 TCA’s can have quinidine-like effect on the cardiac conduction system, potentially causing QRS and QT prolongation and cardiac dysrhythmias. These effects are due to inhibition of fast sodium channels. In instances of cardiovascular toxicity due to TCA overdose, the most effective intervention is hypertonic sodium bicarbonate (NaHco3). It can correct QRS prolongation, reverse hypotension, and treat ventricular dysrhythmias.
709 Fresh frozen plasma rapidly reverses warfarin’s effects whereas vit K requires time for clotting factor re-synthesis.
710 Preterm infantss are risk of hemorrhagic disease of the newborn, a condition characterized by cutaneous gastrointestinal and intracranial bleeding. Administer vit K parenterally
712 Hepatotoxicity and myopathy are common side effects associated with statin therapy. Myopathy can elevate serum creatine kinase activity .
713 Transient ischemia attacks are treated with Aspirin and these inhibit cox 1 at lower doses and cox 2 at higher doses. This increases the chance of GI bleeding.
714 Aspirin acetylates Cox1 and cox2 causing irreversible inhibition. Other NSAIDs produce reversible COX inhibition.
716 Cox-2 inhibitors have potent anti inflammatory effects with less risk of bleeding and GI ulceration.
719 glucocorticoids are used as short-term therapy for rheumatoid arthritis.
724 Antigenic similarity between bacterial antigens and normal self antigens in the heart and CNS are believed to cause formation of anti-self antibodies resulting in rheumatic fever.
725 PSGN can follow either a skin infection (impetigo) or an episode of strep pharyngitis, whereas rheumatic fever is associated only with strep throat infection.
726 PSGN caused only by nephritogenic strains of S.pyogenes (Group A strep). This is immune complex (type III) and will occur regardless of the treatment of the offending strep infection. Administering early penicillin in kids will decrease the chances of cardiac heart valve surgeries.
727 Anterior nares are the most common site of colonization for both MRSA and MSSA.
730 S.pneumoniae has polysaccharide capsule that inhibits phagocytosis. The capsule is antigenic, S. pneumoniaie infection elicits anti-capsule ab production and lasting immunity against the strain. The polysaccharide capsule is responsible for capsular swelling.
734 adult pneumococcal vaccine is an unconjugated polysaccharide vaccine that, unlike the infant vaccine, does not stimulate a T-helper response.
735 strep pneumo is most common cause of bacterial meningitis in adults and is responsible for high neutrophil count in CSF.
737 N.meningitidis enters pharynx –>blood –>choroid plexus —>meninges.
741 serum sickness sx inlcude fever, urticaria, arthralgias, glomerulonephritis and lymphadenopathy 5-10 days after exposure to an antigen, arthralgias, vasculitis with fibrinoid necrosis and neutrophil infiltration and can be features of systemic deposition of circulating immune complexes in arteries and arterioles.. Sulfonamides can exacerbate this. This is type III HS so complent is used up decreasing serium c3 levels.
742 Glomerulonephritis, a photosensitive skin rash and arthralgias in young female is suggestic of SLE. 10-30% of pts have lupus anticoagulant, the most frequent cause of a prolonged PTT and a false positive VDRL without any other hematological abnormality. Lupus anticoagulant can cause an antiphospholipid syndrome defeined by elevated blood lvls of antiphospholipid antibodies with hypercoagulability (venous and arterial thromboembolism) and second or third trimester miscarriages
743 Reiter’s syndrome ppl tend to develop sacroiliitis.
744 chronic renal allograft rejection is mediated by recipient antibodies to graft endothelium formed after engraftment and causes an obliterative intimal smooth muscle hypertrophy and fibrosis of cortical arteries. Hyperacute rejection causes vascular fibrinoid necrosis, neutrophil infiltration, and infarction of the graft. Acute rejection maybe be cellular or humoral causing interstitial mononuclear infiltrate. and or graft vasculitis.
747 Acute hemolytic transfusion reactions are Type II hypersensitivity mediated wherein host antibody binds antigen on transfused donor cells, activating complement and resulting in complement mediated lysis. Anaphylatoxins mediate vasodilation and symptoms of shock.
750 IgE mediated parasitic killing involves antibody-dependent cellular cytotoxicity (ADCC) with ezymes from the cytoplasmic granules of eosinophil releasing major basic protein and other enzymes.
753 Enthesopathies (inflmmation at sites of tendon insertion) are common in ankylosing spondylitis. Involvement of costovertebral and costosternal junctions may cause limitation of chest movements, resulting in hypoventilation.
757 synthesis of steroid hormones and drug detoxificaion occur in the smooth endoplasmic reticulum. Cytosolic proteins are synthesized by free ribosomes. secretory proteins are synthesized by ribosomes on the RER.
759 IL-4 is responsible for B-cell growth, TH2 lymphocytes and B cell isotype switching. Also helps in differentiation of naive T helper cells into TH2 helpers, thus increasing the TH2 cell levels.
760 Tetanus vaccination elicits humoral immunity specific for the tetanus toxin. Exotoxin tetanospasmin blocks the release of inhibitory neurotransmitters from inhibitory motor interneurons in the CNS.
762 pts with IL-12 receptor deficiency are given IFN-gamma to treat mycobacterial infections–can cause recurrent infections in kids.
763 Sublingual mass imparing breathing infant is due to the lingual thyroid which failed to migrate from the foramen cecum to its usual location
765 Hypothyroidism is a common cause of elevated CPK level. Other causes include medications such as HMG co-A reductase inhibitors (statins), autoimmune disease (polymyositis/ dermatomyositis) and muscular dysrophies like Duchenne.
766 Iodide salts inhibit synthesis as well as release of thyroid hormones. Anion inhibitors (perchlorate, pertechnetate) block iodide absorption by the thyroid gland via competitive inhibition. Thionamides (methimazone and PTU) inhibit thyroid peroxidase.
767 energy dependent trasport of inorganic iodide into thyroid follicular cell is a symporter located at the basolateral membrane of the thyroid follicular cell. They take up other ions such as perchlorate, pertechnetate and even radioactive iodine. These competitively inhibit each other’s uptake. So by administering potassium iodide, can decrease the uptake or radioactive isotopes of iodine.
770 thyroid peroxidase catalyzes iodide oxidation/ thryoglobulin iodination.
771 Both chromaffin cells of adrenal medulla and parafollicular cells (c-cells) of thyroid originate from neural crest.
772 Increase in levels of thyroid binding globulin lead to increase in circulating total T4 and total T3 because the bound form increases. However, the level of free thyroid hormone remains same so TSH lvls remain normal. Increase in TBG is typically seen in pregnancy, with use of oral contraceptives, or with hormone replacement therapy.
774 pentazocine has no abuse potential and works through partial agonist activity and weak antagonist acitivity at mu receptors. Because of it weak antagonistic effects, it can cause withdrawal sx in pts who are dependent or tolerant to morphine or other opioids.
775 Beta-endorphins and ACTH and MSH are derived from same precursors, which is proopiomelanocortin (POMC).
776 Mu receptors are G protein-linked receptors whose actions are mediated through various secondary messenger pathways. One identified pathway involves increased potassium efflux. Binding of morphine to mu receptors results in G-protein coupled activation of potassium conductance. Potassium efflux causes hyperpolarization of postsynaptic neurons effectively blocking pain transmission.
777 ketamine blocks NMDA receptors which are usually stimulated by Glutamate. NMDA is believed to enhance morphine tolerance by increasing phosphorylation of opioid receptors and increasing NO levels.
778 The combination of statins plus fibrates increases the risk of myopathy in pts being treated for hyperlipidemia. Statin use is also a/w hepatotoxicity. The combo of fibric acid derivatives and bile acid-binding resins increases the risk for cholesterol gallstones. This reflects an increased cholesterol concentration in bile.
780 Statins cause myopathy and liver toxicity in some pts so warrants liver function tests.
782 Hyperchylomicronemia (hypertryglyceridemia) is a characterisitc acute pacreatitis causing abdominal pain.
784 Pts info can’t be disclosed to others, without permission, including loved ones and family members.
786 Vitamin B12 is infused parenterally.
787 Diminished iron levels or hypoxia causes a decrease in hepcidin levels, which leads to increased intestinal absorption of iron and increased iron release from macrophages. Total iron body content is regulated through the effect of hepcidin (made in liver) on the intestinal epithelial cells’ absorption of dietary iron and the macrophages release of iron.
790 MAP kinase signal transduction pathway includes Ras protein, a G-protein that exists in inactive (GDP-containing) and active (GTP-containing) forms. Muated (permanently activated) Ras is a/w the developement of malignant tumors.
794 Alzheimers shows hippocampal atrophy.
799 oxygen therapy for ARDS. Complication of oxygen therapy is retinal damage.
800 Lecithin aka dipalmitoyl phosphatidylcholine. An L/S ratio > or equal to 2.0 indicates adequate surfactant production to avoid neonatal hyaline membrane disease.
802 3-base pair deletion that removed phenylalanine at amino acid positino 508 of the CF transmembrane conductance regulator (CFTR). This mutation impairs posttranslational processing of the CFTR gene transcript, causing complete absence of CFTR protein from the apical membrane of exocrine duct epithelial cells in pts with high sweat chloride test. Decreased ion conduction by transmembrane protein is seen in milder forms.
804 Normally, in sweat glands, CFTR protein facilitates the absorption of high quanitites of luminal sodium chloride. In other exocrine glands, CFTR is responsible for secretion of chloride ions into the lumen, and also has tonic inhibitory effect on the opening of the apical sodium channel (which is responsible for sodium resorption into the cell). CF pts with normal sweat chloride test have abnormal baseline transepithelial potential difference.
811 Hydronephrosis, renal interstitial atrophy and scarring ensue in resultant reflux nephropathy due to bladder outflow obstruction in BPH pts.
817 A high urine citrate concentration has a stone-preventing effect. Citrate binds to free (ionized) calcium preventing its precipitation and facilitating its excretion. low urine pH forms uric acid and cystine stones and can precipitate calcium stones as well.
822 HBV causes hepatocellular carcinoma by integration of viral DNA into the genome of the hepatocytes.
829 Microangiopathic anemia is a hemolytic anemia and this decreases serum haptoglobin level and as well as increases LDH and bilirubin.
830 Diminished urinary excretion of radiolabeled vit B12 in Schilling’s test is a sign of impaired intestinal abosrption.
837 Inadequate recanalization of the ureteropelvic junction, the junction between the kidney and the ureter, is the most common cause of fetal hydronephrosis.
839 Injury to posterior urethra is a/w pelvic fracture whereas anterior urethral injury most commonly occurs in straddle injuries. A retrograde urethrogram should be performed. YOu do feel a sensation of fullness of bladder.
840 alteration of gene expression in Huntington disesae is due to hypermethylation of histones, which prevention transcription of certain genes.
841 Dimercaprol for Arsenic poisoning. CaNa2EDTA for lead and merury poisoning. Deferoxamine for iron poisoning.
844 Thoracocentesis should be performed above the 7th rib in MCL, 9th rib along Mid axial line and 11th rib along posterior scapular line. Insertion below these points increases the risk of penetrating abdominal structures. Insertion of needle on the inferio margin of the rib risk striking the subcostal neurovascular bundle.
846 Aldose reductase converts galactose to galactitol and glucose to sorbitol.
849 Glucagon increases serum glucose by increased production of glucose from the liver. And it stimulates the insulin secretion from pancreas. Unlike epinephrine, gluacagon has an insignificant effect on skeletal muscle cells and adipocytes.
850 the best short acting insulins for post-prandial hyperglycemia is insulin aspart and lispro. Basal long acting ones are NPH and Glargine.
852 short acting barbiturate like thiopental redistributes into skeletal muscles and adipose tissue, which results in rapid recovery from anesthesia.
853 hepatotoxicity is a side effect of halothane (anesthetic) administration. Massive centrilobular hepatic necrosis is a severe complication of halothane exposure (forms autoantibodies against liver proteins.)
856 the cause of rapid plasma decay of thiopental was not metabolism of the drug but rather redistribution of the drug to other tissues throughout the body.
857 N-acetyl cysteine is used for treating acetaminophen toxicity. It acts as a glutathione substitute and binds to the toxic metabolite. It also provides sulfhydryl groups to enhance the non-toxic sulfation elimination of acetaminophen.
859 side effects of colchicine are nausea, abdominal pain and diarrhea.
861 in pts who excrete large amounts of uric acid, uricosuric drugs should be avoided to prevent uric acid nephrolithiasis. Long term treatment involvement involves xanthine oxidase inhibtitors.
862 Presbyopia is an age related condition which makes it harder to see near objects. Pathogenesis is the sclerosis of lens leading to decreased elasticity.Age related presbyopia may lead to improvement in distant vision such as in myopic patients.
863 Familial retinoblastoma occurs as a result of each of the two Rb genes (two hits). These patients have increased risk of secondary tumors, especially osteosarcomas, later in life. The active (dephosphorylated) Rb protein does not allow the cell to proceed from G1 to the S stage of the cell cycle. Inactivation of the Rb protein permits cell division.
865 polyethylene glycol is an osmotic laxative so is lactase deficiency.
866 body temp >40C is hyperpyrexia and may lead to permanent brain damage if left untreated. Emergent treatment of hyperpyrexia should consist of increasing body heat loss (cooling) and decreasing the hypothalamic set point (antipyretics). Cold blanks are the best initially.
873 Chronic alcoholism can give rise to follic acid deficiency anemia. It is a megaloblastic anemia that develops due to decreased synthesis of purines and thymidine. Peripheral blood smear reveals macrocytosis, ovalocytosis and hypersegmented neutrophils.
876 Atopic dermatitis is associated with asthma.
879 OCP’s inhibit synthesis of FSH and LH. They also thicken cervical mucus that prevents sperm from accessing the uterus and progestin prevents growth of the endometrium making it unsuitable for implantation of an embryo.
880 synaptophysin is found in the presynaptic vesicles of neurons, neuroendocrine and neuroectodermal cells. CNS tumors of neuonal origin frequently stain positive for synaptophysis on immunohistology. Neoplasms of glial origin (astrocytomas, ependymomas, and oligodendrogliomas) stain for GFAP.
881 histological changes in the hepatocytes in reye’s syndrome is microvesicular steatosis, the presence of fat vacuoles in the cytoplasm of hepatocytes. Jaundice is rare in Reye’s syndrome
884 Kimmelstiel-Wilson lesions tend to be localized in the periphery of the glomerulus and is pathognomonic for diabetic nephropathy. Mesangial matrix volume is increased along with the thickening of the glomerular basement membrane. hyperglycemia in diabetic nephropathy induces ANP release that causes increase in hydrostatic pressure in the glomerular capillary, increased GFR and glomerular hypertrophy
886 Hypokalemia is one of the most serious complications of the recovery phase of ATN.
890 Triad of hemolytic anemia include anemia, reticulocytosis and increased indirect bilirubin.
895 When sodium metabisulfite is added, rbcs will sickle, even in sickle cell trait rbcs of ppl with HbA and HbS.
899 Amiodarone along with the class IA and other class III antiarrhythmics will cause prolongation of QT interval on EKG because they all slow phase 3 of the repolarization in the ventricular myocardium. Amiodarone does not predispose to torsade de pointes, as the remainder agents do. Verapamil would prolong PR interval and could predispose to AV nodal block. Adenosine acts on the AV node but its effect is transient.
900 lidocaine can act on ischemic myocardium.
901 K+ channel blockers: Amiodarone, sotalol, ibutilide and dofetilide.
903 Bosentan is a competitive antagonist of endothelin receptors and is used for treatment of primary (Idiopathic) pulmonary arterial hypertension. It is a/w decreased apoptosis of endothelial and smooth muscle cells in pulmonary arterioles.
905 Rneal cell carcinomas arise from epithelial cells of the proximal renal tubules. high lipid content. tumor appears as a golden yellow mass and in microscopy, they are composed of cells with abundant clear cytoplasm and eccentric nuclei.
907 temporal lobe involvement is characteristic of HSV-1 encephalitis.
909 Tabes dorsalis occurs due to demyelination of dorsal columns and dorsal roots of the spinal cord. Loss of proprioception and vibration senses, ataxia and Argyll Robertson pupil may be seen.
913 median age of onset of temporal arteritis is 65yrs. Called giant cell artertitis cuz can form multinucleated giant cells. Can cause narrowing of the vessel and common Sx include heaache, craniofacial pain syndrome :jaw claudication, tongue claudication and facial pain, Polymyalgia rheumatica and sudden vision loss.
917 Axonal denudation means axonal demyelination and is a hallmark of multiple sclerosis. pts can have diplopic episodes that can resolve spontaneously and shows slow adduction of the left eye when the patient looks to the right.
919 multiple sclerosis — increased levels of IgG in the CSF, detected as an oligoclonal band on electrophoresis.
920 TZD’s activate PPAR-gamma, which is the nuclear receptor that alters the transcription of genes responsible for glucose and lipid metabolism. TZD’s exert their glucose-lowering effect by decreasing insulin resistance.
922 High blood glucose levels in maternal circulation crosses the placenta causing fetal hyperglycemia and Islet cell hyperplasia. Hyperinsulinemia caused by islet cell hyperplasia is thought to cause fetal macrosomia. Once free from the mother, the neonate continues to overpoduce insulin, which can cause the neonate to experience severe hypoglycemia.
927 elevated baseline ACTH levels with moderate suppression of cortisol in the dexamethasone suppression test = cushing syndrome due to a pituitary adenoma. elevated baseline ACTH levels and little/no suppression of cortisol levels = ectopic ACTH production. low baseline ACTH, little/no cortisol suppresion = cushing syndrome stemming from primary adrenal process.
932 Rx of adrenal crisis is administration with stress-dose corticosteroids.
933 catecholamine excess = hypertension, tachycardia and diaphoresis. pheochromocytoma = intermittent headaches, hypertension, diaphoresis and pallor or flushing. Episodic hypertension is imp in diagnosing pheochromocytoma.
934 Glucose is converted to Sorbitol by aldose reductase. Sorbitol is converted to fructose by the oxidation process via sorbitol dehydrogenase.
935 Actininc keratoses – erythematous papules with a central scale and sandpaper like texture. can develop into squamous cell carcinoma Seborrheic keratoses – stuck- on appearance, deeply pigmented or flesh-colored lesions with velvety or greasy surface.
936 Benign acanthosis nigricans is associated with insulin resistance. Malignant acanthosis nigricans is caused by gastric adenocarcinoma.
938 Schilling test is used to differentiate between dietary deficiencey of vit B12, pernicious anemia and malabsorption syndromes. Low absorption of cobalamin not correctable by intrinsic factor is indicative of a malabosrption syndrome such as ileal disease, pancreatic insufficiency or bacterial overgrowth
942 Desmopressin acetate (DDAVP) stimulates release of factor 8 and vWF from endothelial cells, and also used in the treatment of hemophilia A
948 Mechanism behind ACE inhibitor induce cough is accumulation of bradykinin, substance P, or prostaglandins.
950 Source of myocardium energy is via fatty acid oxidation, glucose oxidation and glycolysis. Glucose oxidations requires less oxygen so its better to shift the energy production in treating chronic stable angina, where there is less oxygen use per one ATP synthesized since athersclerosisn in stable angina leads to reduced oxygen delivery to cardiac mitochondria resulting in myocardial oxygen demand and supply mismatch.
951 most of the blood supply to the heart occurs during diastole and the duration or length of disatole is a critical factor in determining coronary blood flow.
955 aromatase converts androstenedione to estrone and testosterone to estradiol. It converts androgens into estrogens in the ovaries, testes, placenta and other peripheral tissues. Genetic deficiency of this enzyme leads to an inability to synthesize estrogens. It presents with maternal virilization during pregnancy and masculinization of the female fetus.
956 check for urine chloride in metabolic alkalosis. Thiazide and loop diuretics increase renal losses of Na, which is followed by excretion of Cl.
957 Cold agglutinins are antibodies that can destroy rbc’s and cause mile anemia. Recovery of the anemis is due to the faded immune response.
960 Leggionella causes disease in smokers and can also cause gastrointestinal sx.
965 Protein conjugation causes a T cell mediated immune response leading to immunoglobulin class switching and geneartion of memory B-lymphocytes. This wouldn’t occur with pure polysaccharide immunization.
968 Most appropriate prevention measure to control rise in incidence of neonatal tetanus is vaccination of young adults.
971 B.anthracic spreads via lymphatics to the bloodstream, and the organism multiplies in the blood and tissue. Cutaneous anthrax is the most common form of this disease; pulomanry anthrax accounts for approximately 5% of cases. Anthrax is commonly acquired occupationally by those who handle livestock that have not been immunized for the disease.
973 ecthyma gangrenosum is caused by pseudomonas which are common in neutropenic pts, hospitalized pts, pts with burns and chronic indwelling catheters.
974 Hot tub folliculitis caused by pseudomonas results in a pruritic papulopustular rash. psuedomonas shows gram negative, oxidase positive, non-lactose fermenting, motile rods that produce pigment.
976 V.cholera and ETEC cause a purely toxin-mediated watery diarrhea. The toxins secreted by these organisms do not cause cell death. They modify electrolyte handling by enterocytes so no blood or pus is noted in stool microscopy during infection by these organisms. YOu see mucus and epithelial cells.
979 Chronic renal failure causes secondary hyperparathyroidism. low calcium, high PTH and low phosphorus due to dysfunctional kidney tubules.
980 Increased calcium levels seen with Hydrochlorothiazide therapy usually suppresses PTH and causes hypercalcemia and hypocalciuria.
988 MEN 1- parathyroid tumor, pituitary adenoma (prolactin, ACTH), pancreatic tumor (inuslinoma, gastrinoma, VIPoma and glucagonoma). MEN2a – Medullary carcinoma, Pheochromocytoma, parathyroid tumor MEN2b – Medullary carcinoma of thyroid, Pheochromocytoma and Marfanoid habitus/ Mucosal neuromas.
990 Sunlight exposure catalyzes the first reaction in the chain of active vit D synthesis: 7-dehydrocholesterol transforms to cholecalciferol (Vitamin D3). Then, 25-hydroxylation occurs in the liver and the kidney enzyme 1-alpha hydroxylase catalyzes the final step in the synthesis of active vitamin D.
991 1 alpha hydroxylation converts calcidiol to calcitriol in the renal tubules.
992 PTH causes the formation of the calcium-absorbing vitamin D. Calcitonin is secreted by parafollicular C cells in the thyroid. It battles high serum calcium by decreasing bone resporption via osteoclast inhibition.
993 Hydrochlorothiazide is ideal for treating HTN or CHF in a woman who is also at risk of osteoporosis because of increase in serum calcium levels by the drug.
994 TSH, glucagon, PTH and beta receptors use Gs CAMP pathway.
997 After 12 to 18 hrs of fasting, gluconeogenesis is the principal source of blood glucose.
998 Lysine and leucine are ketogenic and would not increase blood lactate levels in pts suffering from pyruvate dehydrogenase deficiency.
999 35-37 weeks gestation pregnant women. Intrapartum antibiotics are required, most frequently with penicillin or ampicillin, to prevent neonatal GBS sepsis, pneumonia and meningitis.
1000 Enterococci produce aminoglycoside-modifying enzymes that transfer diff chemical groups (acetyl, adenyl or phosphate) to the aminoglycoside molecule and therefore impair antibiotic binding to ribosomal subunits.
1002 strep viridans produces dextrans from glucose that aid these organisms in colonizing host surfaces such as dental enamel causing caries, and heart valves.
1003 In order for strep viridans to cause subacute bacterial endocarditis, they require preexisting valve damage leading to local deposition of fibrin in order for them to adhere.
1005 meningococcal pili is helpful in epithelial attachment to nasopharynx.
1006 Meningococcal lipooligosaccharide (LOS) is responsible for many of the toxic effects observed in meningitis and miningococcemia. Blood levels of LOS correlate closely with morbidity and mortality.
1010 Glucokinase is a glucose sensor in pancreatic cells and its defects result in one of the types of maturity-onset diabetes. Inactivating mutations of the glucokinase gene lead to a decrease in enzyme’s function, causing decrease in the metabolism of glucose, lesser ATP formation and diminished insulin secretion. The conversion of glucose to glucose-6-phosphate by glucokinase is crucial and rate limiting.
1013 smoking cessation is by far the most effective preventive intervention in almost every pt.
1015 Verruca vulgaris caused by HPV starins 1-4. Genital warts (condylomata acuminatum)- with strains 6-11. Intraepithelial neoplasia of the cervis and vulva caused by strains 16,18,31,33,35. Koilocytes are pyknotic superficial squamous cells with a dense, irregularly staining cytoplasm and perinuclear clearing.
1018 Lipids are digested in the duodenum and absorbed in the jejunum. Ileum is for absorption of bile and vit B12
1020 Lack of ATP production by defective glycolysis in pyruvate kinase deficiency leads to defective rbc cell architecture which is removed by spleen resulting in work hypertrophy. Antibody production and B cell affinity maturation occur in the white pulp of the spleen. Removal of senescent and defective rbcs occur in the red pulp.
1022 PEP to pyruvate via pyruvate kinase. Pyruvate to oxaloacetate via Pyruvate carboxylase. Oxaloacetate to PEP is via PEPCK, which require GTP that comes from the conversion of succinyl coA to succinate step via succinyl coA thiokinase in the TCA.
1025 there is antigenic variation in the gonococcal pili so pili anti-gonnococcal vaccine is useless.
1028 glycogen degradataion is coupled with skeletal muscle contractino due to calcium-mediated myophosphorylase activation. Increased calcium in the cytosol allosterically actviates phosphorylase kinase, which phosphorlyates (activates) muscle phosphorylase. Calcium increases the catalytic activity of both phosphorylated and dephosphorylated forms of phosphorylase kinase. In the liver, NE can promote glycogenolysis through Gq pathway-mediated calcium influx.
1029 2,3-BPG is produced from 1,3-BPG by the enzyme bisphosphoglycerate mutase. This reaction consumes the energy that would have been otehrwise used by rbc’s to produce energy in the form of ATP.
1030 Debranching enzyme deficiency (cori disease) leads to incomplete glycogen degradation. Alpha 1,6-glucosidic branch points can’t be degraded, so small chain dextrin-like material accumulates with the cytosol of hepatocytes. Pts present with hypoglycemia, hypertriglyceridemia, ketoacidosis and hepatomegaly.
1031 F2,6BP allosterically inhibits F1,6 bisphosphatase. Glucagon causes phosphorylation of bifunctional enzyme composed of PFK2 and F2,6 bisphosphatase, leading to inactivation of the kinase and activation of the phosphatase. High concentration of F2,6-bisphosphate has low rate on teh conversion of alanine to glucose, but not on the pyruvate to oxaloacetate.
1032 Muscle glycogen is converted to glucose-1-phosphate via muscle phosphorylase, which is deficient in McArdle’s disease.
1033 Lipoic acid is cofactor for enzymes such as pyruvate dehydrogenase, alpha ketoglutrate dehydrogenase and branched chain ketoacid dehydrogenase.
1034 acetyl-coA is an imp allosteric activator of gluconeogenesis that acts by increasing the activity of pyruvate carboxylase.
1035 Nonoxidative reactions of the HMP shunt oare reversible and so transketolase can synthesize ribose from Fructose-6-phosphate and vice versa.
1036 G6PD converts G6P to 6-phosphogluconate.
1037 The mechanims of hemolysis due to defective RBC glycolysisis different from hemolysis resulting from defects in the HMP shunt in that hemolysis due to glylcolytic defects causes a chronic hemolytic anemia while hemolysis due to HMP shunt defects causes an episodic hemolytic anemia. Gluathione reductase deficiency causes a similar clinical picture and is pathophysiologically similar to G6PD deficiency.
1039 TNF-a is shown to induce a wasting syndrome (cachexia), which encompasses anorexia, malaise, anemia, weight loss and generalized wasting due to underlying systemic disease. TNFa causes necrosis of some tumors in vitro and mediates paraneoplastic cachexia in humans by suppressing appetite, inhibiting lipoprotein lipase and increasing insulin resistance of peripheral tissues.
1042 In herpes zoster (shingles), pt presents with a painful vesicular rash in a dermatomal distribution. Intranuclear inclusions in kertatinocytes and multinucleated giant cells are seen. Positive Tzanck smear test.
1044 Biologically active form of pantothenic acid is coenzyme A, which binds with oxaloacetate in the first step of the TCA cycle to form citrate and then succinyl-coA. Coenzyme A is also imp in sytnhesis of Vit A, D, cholesterol, steroids, heme A, fatty acids, amino acids and proteins
1045 Vit A is beneficial in treating measles infection.
1046 female athlete triad constist of an eating disorder, amenorrhea and osteoporosis.
1048 Acute toxcity of vit A can cause nauses, vomiting, vertigo and blurred vision, Chronic toxicity includes alopecia, dry skin, hyperlipidemia, hepatotoxicity, hepatosplenomegaly and visual difficulties. Papilledema due to intracranial hypertension. Teratogenic effects include cardiac anomalies and fetal death (in first trimester). Vit A overuse can result in intracranial hypertension, skin changes and hepatosplenomegaly.
1053 pts of ATN experience tubular re-epithelization and regain renal function. ATN clinical course: initiation, maintenance (oliguric) and recovery phase Initiation : renal tubule cell damage where GFR falls and urine output decreases. Maintenance (oliguric) phase: GFR low, urine output low/absent. Lasts 1-2 weeks and light microscopy shows granular casts in the tubular lamina. Recovery phase: re-epithelization of tubules. Polyuria and GFR normalization
1055 Increased plasma FSH reflects gonadal failure in pts with Klinefelter syndrome. The estrogen:testosterone ratio determines the extent of feminization.
1056 cooper’s ligament infiltration by invasive breast cancer causes retraction of the overlying skin
1058 GBS can occur after febrile illness, vaccination or allergic reaction. There is ipsilateral paralysis and hyporeflexia. There is cross reacting autoimmune attacks and demyelination is followed by an endoneural inflammatory infiltrate consisting of lymphocytes and macrophages.
1060 Diabetic mononeuropathy involves CNIII. Never damage is ischemic and only somatic nerve fibers are affected so see ptosis and down and out gaze in conjunction.
1064 Niacin is essential component of coenzymes NAD and NADP. Niacin is derived from Tryptophan. Niacin deficiency can lead to pellagra.
1066 Oxidative reactinos of the HMP shunt are necessary for anabolic reactions that utilize NADPH as an electron donor (including cholesterol and fatty acid synthesis). Also, NADPH produced via the HIMP shunt is the only method of reducing glutathione (and thus repairing oxidative damage) available to red blood cells.
1067 Essential fructosuria due to fructokinase deficienc is an asymptomatic disorder. Fructose from diet is absorbed in gut and secreted in the urine unchanged due to defective metabolism. Fructose similar to glucose and galactose, is a reducing sugar and can be detected by clinitest tablets, which test of presence of reducing sugar. A urine dipstick, however, utilizes glucose oxidase for determination of the presence of urine glucose.
1069 Aldolase deficiency causes hereditary fructose intolerance. Manifests after introduction of fructose into the diet with vomiting and hypoglycemia about 20-30 mins after fructose ingestion.
1070 In pts with essential fructosuria, metabolism of fructose by hexokinase to fructose-6-phosphate is the primary method of metabolizing dietary fructose.
1071 class galactosemia arises from deficiency of galactose-1-phosphate uridyl transferase. clinical features include vomiting, lethargy and failure to thrive soon after breastfeeding begins.
1072 Lactose is aka Galactosyl B-1,4-glucose. Lactase is aka B-galactosidase.
1076 Heparin is doc for acute management of venous thrombosis or thromboembolism. Heparin activates ATIII. Warfarin is used for long-term prevention of recurrent venous thromboembolism. Warfarin inhibits vit K dependent gamma carboxylation of glutamic acid residues.
1077 Heparin is doc for prevention of venous thrombosis in non-ambulatory pts or pts undergoing elective surgery. Unfractionated heparin bind to ATIII by a pentasacchardie in the heparin chain.
1078 Heparin induced thrombocytopenia (HIT) can be treated with direct thrombin inhibitors like hirudin, lepirudin and argatroban.
1079 Abciximab is a blocker of GP IIb/IIIa is either deficient or defective in pts with Glanzmann thrombasthenia.
1080 Cilostazol is a PDE inhibitor used in pts with intermitten claudication. Inhibits platelet aggregation and is also a direct vasodilator.
1082 Fibrinolytics such as tPA may cause reperfusion arrhythmia on arterial re-opening. Accelerated idioventricular arrhythmias is a common reperfusion arrhythmia.
1084 Metalloproteinases are Zn-containing enzymes and participate in normal tissue remodeling and in tumor invasion through the basement membrane and connective tissue.
1085 BCR-ABL codes for a protein with tyrosine kinase activity which stimulates proliferation of granulocytic precursors that lead to development of CML. This tyrosine kinase activity can be inhibited with Imatinib.
1086 follicular lymphoma is the indolent lymphoma that has painless waing and waning lymphadenopathy.
1090 Cimetidine, amiodarone and TMP-SMX inhibit warfarin metabolis. Cholestyramine binds warfarin and decreases its therapeutic effects as well.
1092 DPT vaccine contains diphtheria toxoid, which stimulates production of neutralizing antibodies (IgG) against the binding comoponent (B subunit) of the diphtheria exotoxin.
1093 corynebaterium diphtheria have polar granules that stain deeply with aniline dyes.
1094 diptheria AB-exotin. The A (active) subunit of this exotoxin transfers a ribose residue from NAD to a histidine on the elongation factor-2 (EF-2). The EF-2 protein is essential for peptide chain translocation on the ribosome in the process of translation. Ribosylation inactivates EF-2, thus inhibiting protein synthesis and causing cell death.
1096 Ecoli and staph.saprophyticus are most common causes of cystitis and acute pyelonephritis.
1099 Traveler’s diarrhea is most frequently related to ETEC that produces heat labile (LT, choleragen-like) and heat stable (ST) enterotoxins. LT activates adenylate cyclase leading to increased cAMP, and ST activates guanylate cyclase leading to increased cGMP. Both cause water and electrolyte loss and watery diarrhea.
1100 EHEC doesn’t ferment sorbitol and doesn’t produce glucoronidase. It inactivates the 28s of the 60s subunit. Bacteria that activate adenylate cyclases are Anthrax edema factor, cholera toxin, pertussis toxin, ETEC heat labile toxin, c.jejuni enterotoxin and bacillus cereus (heat labile enterotoxin). Toxins that activate guanylate cyclase are ETEC (heat stable toxin) and Yersinia enterocolitica (Y.enterocolitica enterotoxin). C.difficle disrupts cytoskeleton(depolymerizes actin
1101 Edema factor is a calmodulin dependent adenylate cyclase that causes an increase in cAMP concentration inside host cells. Edema factor suppresses neutrophil function and accumulation of fluid within and between cells leading to edema. Bordatella pertussis produces an edema factor -like exotoxin called “extracellular adenylate cyclase”.
1102 Nontypable strains of H.influenza are strains that do not form an antiphagocytic capsule, and immunity is not conferred by vaccination with the Hib vaccine.
1106 sweat gland secretion into hair follicles = apocrine Apocrine glands are innervated by the adrenergic fibers of teh sympathetic nervous system and are not functional until puberty. Holocrine glands are sebaceous glands. sweat secretion directly onto skin surface is via eccrine/merocrine glands.
1113 Active vertical growth (depth of invasion (Breslow thickness)) is the most imp prognostic indicator for pts with malignant melanoma
1114 urticaria acquired through antibiotic allergic reaction is characterized by superficial edema and lymphatic channel dilation.
1115 Spongiosis is histologic finding in pts with contact dermatitis
1117 psoriassis —hyperparakeratosis, acanthosis, rete ridge elongation, mitotic activity above the epidermal basal cell layer and reduced or absent stratum granulosum. Munro microabscesses — neutrophils may form spongiotic clusters in the superficial dermis and the parakeratotic stratum corneum.
1118 ANP increases cGMP by increasing its production, whereas NO increases cGMP by preventing its degradation by blocking phosphodiesterase.
1119 B-oxdiation of fatty acids, ketogenesis, citric acid cycle, parts of urea cycle (carbomoyl phosphate synthetase 1 and ornithine transcarbamoylase) and pyruvate carboxylation all occur exclusively within the mitochondria. All of the reactions of the pentose phosphate pathway occur in the cytoplasm.
1121 Insulin is an anabolic hormone that acts via tyrosine kinase second messenger system to stimulate synthesis of glycogen, proteins, fatty acids and nucleic acids. Tyrosine kinase leads to activation of protein phosphatase within cells. Dephosphoryaltion of glycogen syntase activates it promoting glycogen synthesis. In other scenario, dephosphorylation of F1,6-bisphosphatase inactivates the enzyme inhbiting gluconeogensis.
1132 Chediak higashi is consisted of immunodeficiency, albinism and neurologic defects(nystagmus and peripheral and cranial neuropathies). defect in neutrophil phagosome lysosome fusion causes abnormal giant lysosomal inclusions seen on peripheral blood smear. Abnormal melanin storage in melanocytes causes partial oculocutaneous albinism.
1133 poison ivy dermatitis is one form of allergic contact dermatitis, which is a type IV hypersensitivity reaction. Type IV HS are mediated by T lymphocytes. The cutaneous lesiosn in poison ivy dermatitis are typically linear erythematous papules, vesicles or bullae that are pruritic. Cd8+ T cells are the main effector cells in allergic contact dermatitis and are the first cells to be recruited in the elicitation phase.
1139 Fimbrial antigen for UTI caused by ecoli
1140 lipid A in LPS causes activation of macrophages, which leads to widespread release of IL-2 and TNF-alpha, which inturn cause the signs and sx of septic shock. Capsule of e.coli is a virulence factor that allows the bacteria to survive hematogenous spread and to establish meningeal infection. E.coli causing neonatal meningitis do possess the K-1 antigen.
1141 septic shock by Ecoli is due to LPS endotoxin which contains Lipid A that induces shock by activation of macrophages and granulocytes. Septic shocks sx inlcude fever, sking flushing and altered level of consciousness.
1142 The most common cause of E.coli bacteremia is a UTI. E.coli is part of the normal bowel flora, and special adhesive proteins allow some strains to colonize and ascend the urinary tract. This can result in pyelonephritis or bacteremia and sepsis from access to the bloodstream.
1147 sarcoidosis constitutional symptoms include bilateral hilar adenopathy and non caseating granulomas
1148 Ace inhibitors cause decreased GFR which elevates creatinine, hyperkalemia and cough.
1149 Foot drop is due to injury to common peroneal nerve.
1150 Tumors adjacent to falx cerebris are typical meningioma locations. Compression of teh parasaggitttal cortex causes contralateral spastic paralysis of the leg. Focal seizures may also occur.
1152 Craniopharyngioma- intracranial calcified mass that has cystic spaces with a yellow, viscous fluid that is rich in cholesterol.
1154 Lymphogranuloma venereum is a chronic disease characterized by an initial small papule on the genital mucosa that contains cells infected with C.trachomatis. This papule is followed weeks later by swollen, painful inguinal nodes which coalesce, ulcerate and rupture.
1164 NE leak during an infusion causes alpha 1 mediated vasoconstriction. This can be prevented via infusion of an alpha blocker like phentolamine mesylate.
1165 Hallucionogens (psychomimetic drugs), amphetamines, and cocaine is mostly a/w violent behavior. Hallucionogens include LSD, PCP and mescaline. Belligerence and psychomotor agitation tend to be more common with PCP than with LSD intoxication.
1168 colchine inhibits tubulin polymerization and causes diarrhea, nausea and vomiting.
1170 Prospect of lead-time bias when evaluating any screening test. Typical example is when an apparent increase in survival in pts diagnosed with a new test who actually have an unchanged prognosis.
1176 Relative risk reduction = ((AR)control- AR treatmen)/ AR control
1182 adverse reactions to antibiotic therapy include GI upset to photosensitivity to modification in the fucntioning of the cytochrome p450 enzymes, which may cause toxicities from other drugs. Disruption of gut flora makes prone to C.difficile infection. Don’t prescribe antibiotics for upper respiratory viral infections and otitis media — usually antibiotics falsely prescribed for these conditions.
1186 ARP represents the excess risk in the exposed population that can be attributed to the risk factor.
1188 loss to follow-up in prospective studies creates a potential for selection bias.
1189 Matching is used in case-control studies in order to control confounding. Matching variables include age and race.
1193 Lithium, valproic acid and carbamezapine are mood stabilizing agents. Valproic acid and carbamazepine also work as anticonvulsants. Valproic acid increases the inhibitory effect of GABA in the CNS.
1194 In pregnant women, heparin is used to treat DVT. t-PA is sued to treat ST elevation MI and ischemic stroke. Clopidogrel inhibits ADP mediated platelet aggregation, used for treatment of coronary artery disease, peripheral vascular disease, and cerebrovascular disease.
1195 nystatin used to treat oropharyngeal candidiasis in immunosuppressed patients. Nystatin forms pores.
1196 selective Beta blocks like Metoprolol, atenolol, acebutolol and esmolol are preferred in pts with COPD and/or asthma.
1198 Bacteroides is a gram negative anaerobic bacteria. Piperacillin-tazobactam is effective against most gram (-) enteric rods, including P.aeruginosa. Tazobactam, clavulanic acid and sulbactam are B-lactamase inhibitors.
1199 Carbamezapine blocks voltage gated Na channels in the corticol neurons by stabilizing the channels in an inactivated state. Used to treat simple partial, complex partial and generalized tonic-clonic seizuers. Carbamezapine causes bone marrow suppression, is hepatotoxic and may cause SIADH.
1206 breast cancer, colon cancer and lung cancers in women.
1208 case fatality rate is calculated by dividing the number of fatal cases by the total number of ppl with the disease.
1211 oxybutynin is an antimuscarinic agent commonly used for urge incontinence. Bethanechol and alpha 1 blocker is used to treat postoperative urinary retention.
1212 Paralytiac action of non-depolarizing NMJ blocking drugs can be revesed by anticholinesterase agents including neostigmine. NOt true of depolarizing neuromuscular blockers. The duration of paralysis that is caused by succinylcholilne depends largely on its catabolism by plasma cholinesterase.
1213 beta blockers in thyrotoxicosis decreases the effect of sympathetic adrenergic impulses reachign target organs and a decresae in the rate of peripheral conversion of T4 to T3. Thyrotoxicosis is composed of hypermetabolic, hyperadrenergic state as well as mild congestive heart failure.
1214 corticosteroids decrease the production of ECM collagen and GAG’s. Consequences inclulde atrophy of the dermis with loss of dermal collagen, drying, cracking, and/or tightening of the skin. Telangiectasias, ecchymoses from mild trauma, and atrophic striae may also be found.
1215 acid fast staining includes aniline dye such as carbolfuchsin and decolorizing with acid alcohol.
1217 Sulfatide virulence factor expressed by M.tuberculosis allows for intracellular bacterial proliferation.
1221 Lower lobe lung lesion (ghon focus) followed by ipsilateral hilar adenopathy (calcified lymph node) is described as Ghon complex, which is a primary tuberculosis infection Primary infection occurs after inhaling the organism in aerosolized respiratory secretions of an infected person. Initial M.tuberculosis infection is characterized by a Ghon complex, which consists of a lower lobe lung lesion (ghon focus) and ipsilateral hilar adenopathy.
1223 Mycobacterial resistance to isoniazid can be accomplished through non-expression of the catalase-peroxidase enzyme or through genetic modification of the isoniazid binding site on the mycolic acid synthesis enzyme.
1224 Isoniazid is chemically related to pyridoxine, known as vit B6. It inhibits mycolic acid synthesis in mycobacterial cells and is specific to the mycobacteria. Mycolic acid is a long branched chain saturated fatty acid used in the mycobacterial cell wall and in the formation of virulence factors.
1225 Active tuberculosis treated with drug monotherapy will result in fast emergence of mycobacterial antibiotic resistance from rapid selective gene mutations.
1228 Ethambutol causes optic neuritis that results in color blindness, central scotoma and decreased visual acuity.
1231 Number needed to treat is same as number treated to harm which is 1/ absolute risk increase. Absolute risk increase = Event rate for treatment – Event rate for placebo. Subtract the percentages by dividing the dead number from the drug group and then for the placebo group and then subtract the percentages to get a decimal which then can be used in the NNH formula
1233 NPV is the probability that a pt truly does not have the disease if she tests negative for the disease. NPV is inversely proportional to the prevalent of a disease.
1234 displacemnt can include redirected emotions to either ppl or objects (more acceptable but still inappropriate).
1237 Competent pts have the right to refuse knowledge of their own medical info and diagnoses. Then ask if the pt has any family members who would like to make further decisions about the pts health care.
1239 When treating pts referred to you for specialty care or second opinions, it is imperative to not undermine the pt’s relationship with his or her primary provider.
1240 CO competitively binds to heme.
1241 HbS aggregates in deoxygenated state. Sickling occurs under all conditions a/w anoxia including low pH and high 2,3-DPG.
1242 In HbS a charged glutamic acid residue is replaced by a nonpolar hydrophobic valine residue at the 6th amino acid positino in the beta subunit. This results in alteration of a hydrophobic part of the beta chain that fits into a complementary site on the alpha chain of another hemoglobin molecule. Sickling is promoted by conditions a/w low oxygen lvls, increased acidity, or low blood volume (dehydration).
1245 C-terminal propeptide removal occurs in the extracellular space and converters procollagen to collagen.
1246 extracellular propeptidases cleave disulfide-rich terminal extensions from the procollagen molecule. This results in formation of water-insoluble triple helical collagen fibrils.
1247 Hydroxylation of proline and lysine residues and glycsoylation of hydroxylysine residues and self assembly of alpha procollagen chains into triple helix with disulfide bond formation occurs within RER. Terminal peptide cleavage and collagen fibril crosslinking occur in the extracellular space.
1249 Elastin’s plasticity and ability to recoil upon release of tension is attributable to a unique form of desmosine crosslinking between four different lysine residues on four diff elastin chains. This crosslinking is accomplished by the action of extracellular lysyl hydroxylase.
1252 Direct arterial vasodilators like hydralazine and minoxidil are effective antihypertensives. Because they cause significant arterial vasodilation, they also cause reflex sympathetic activation resulting in tachycardia and edema. To counteract these compensatory effects, these agenst are often given in combination with symapholytics and diurectics.
1253 Drug induced lupus drugs are metabolized by N-acetylation in the liver.
1254 Sodium thiosulfate is used to treat cyanide toxicity and works by donating sulfur to liver rhodanase to enhance conversion of cyanide to thiocyanate.
1255 Rx for neonatal opioid withdrawal is tincture of opium
1256 Naloxone is pure opioid receptor antagonist used to treat opioid intoxication or overdose. It has greatest affinity for Mu receptors
1257 Tolerance to opioid induced constipation and miosis does not readily occur.
1258 Opioid analgesics can cause contraction of smooth muscles in the sphincter of Oddi leading to increased pressures in the bile duct and the gall bladder.
1259 medulloblastoma biopsy of the mass reveals sheets of primitive cells and many mitotic figures.
1260 Most frequent CNS tumor in immunosuppressed pts is a primary CNS lymphoma caused by EBV.
1261 The pineal region is the most common location of brain germinomas. Histologically, germinomas are similar to testicular seminomas. Class sx of pineal germinomas are precocious puberty, parinaud syndrome, and obstructuve hydrocephalus.
1263 Opsoclonus-myoclonus is a paraneoplastic syndrome is associated with neuroblastoma. This tumor, associated with an increased number of copies of the N-myc gene is the most common extracranial neoplasm in children. Mean age of onset is 2yrs old.
1264 Carpal tunnel syndrome is also associated with diabetes mellitus, acromegaly, rheumatoid arthritis and dialysis-associated amyloidosis.
1267 Lambert Eaton: weakness improves during the day and with exercise. Weakness of proximal muscles. Myasthenia gravis: weakness is worse at the end of the day or with exertion. Extraocular muscles are affected first (ptosis, diplopia).
1268 Abnormally slow relaxation of muscles is called myotonia (inability to release doorknob). CTG repeats and skeletal muscles involves myotonia (sustained muscle contraction). Cataracts are seen in pts along with frontal balding and gonadal atrophy are other common features. Type 1 fibers are more affected. Duchenne muscular dystrophy has necrosis of muscle fibers and fibrofatty replacement.
1271 PVV increases as prevelance increases, whereas NPV increases as prevelance decreases.
1272 Power (1-B) is the probability of rejecting a null hypothesis when it is truly false. It is typically set at 80% and depends upon sample size and difference between outcomes.
1275 Observer bias occurs when investigator’s decision is affected by prior knowledge of the exposure status.
1276 In a cross sectional study, exposure and outcome are measured simultaneously at a particular point of time (snapshot study).
1277 A case control study is used to compare the exposure of people with the disease (cases) to the exposure of ppl without the disease (controls). The main measure of association is the exposure odds ratio. Relative risk and relative rate are calculated in cohort studies, in which ppl are followed over time for developing the disease.
1280 Latent period– in this example, at least five years of continuous exposure to antioxidants were required to reveal the protective effect of the exposure on the outcome.
1285 Look at the pic. The degree of overlap between the healthy and diseased population curves limits the max combined sensitivity and specificity of a test (area under the ROC curve). The degree to which sensitivity or specificity is affected depends upon the chose cutoff value.
1292 warfarin induced skin necrosis. Warfarin inhibits both factor 7 (coagulation factor) and protein C (anticoagulant). This relative imbalance results in hypercoagulable state
1294 Both HUS and TTP come under a spectrum of disease. The characteristic pentad is fever, thrombocytopenia, renal failure, neurological manifestations and microangiopathic hemolytic anemia. schistocytes are present in TTP, HUS, DIC and prosthetic valves. TTP occus in adults with predominant neurological symptoms, HUS, in children with renal involvement.
1296 DIC results in decreased circulating fibrinogen and factor 5 and 8 (these are also inhibited by protein C and S).
1297 burr cells = helmet cells = schistocytes.
1300 It is imp to have high sensitivity in screening tests.
1301 A researchers belief in a positive outcome in treated pts can potentially result in oberser bias. Blinidng can reduce observer bias.
1303 The power of a study increases proportionally with the sample size. The larger a sample size the greater the ability to detect a difference when one truly exists.
1304 Biphasic pattern (Antoni A and B areas) and s-100 positivity indicates schwanomma. Shows elongated cells that have regular, oval nuclei and demonstrate areas of dense and loose growth patterns. Acoustic neuroma at the cerebellopontine angle at CN VIII is the most common schwanomma.
1308 you get peripheral nuropathy in isoniazid drug due to deficiency of vitamin B6 caused by the drug.
1309 without mycolic acids, the bacteria loses it acid-fastness and become unable to synthesize new cell walls or multiply.
1310 decreased activity of bacterial catalase-peroxidase is one mechanism of mycobacterial resistance to isoniazid.
1311 Ethambutol toxicity is corneal deposits and affects carbohydrate polymerization as it inhibits arabinosyl transferase, an enzyme that polymerizes arabinose into arbinan and then arbainogalactan.
1312 MAC presents with sx of fever, weight loss and diarrhea in HIV pts. They are acid-fast organisms and azithromycin or clarithromycin are used for prophylaxis for MAC in HIV pts.
1313 Lepramatous leprosy occurs in pts with weak cell-mediated (Th1) immune response. Tuberculous leprosy is the more milder form. Positive lepromin test in tuberculoid leprosy.
1318 demyelination decreases the space constant and is responsible for sx in multiple sclerosis.
1320 increase neostigmine dosage when see myasthenia gravis with edrophonium test.
1323 Muscle paralysis is via muscarinic receptors. MUD PILES from oraganophosphate poisioning results in muscarinic associated problems.
1324 Alpha receptors inhibit insulin secretion and beta receptors stimulate insulin secretion. Pretreatmen with an alpha blocker will result in insulin secretion when epinephrine is administered. Usually, epinephrine inhibits insulin secretion.
1325 hypoglycemia can be precipitated in a diabetic pts after vigorous exercise due to increased glucose uptake by muscles
1326 Aberrant serine and threonine residue phosphorylation by serine kinase leads to insulin resistance. These aberrant phosphorylations can occur in the presence of TNF-alpha, catecholamines, glucocorticoids and glucagon.
1327 A high waist to hip ratio is associated with insulin resistance, metabolic syndrome and type 2 diabetes.
1328 High free fatty acid levels results in insulin resistance. Serine phosphorylation is a known mechanism of insulin resistance inducegon and by TNF alpha, glucagon and glucocorticoids.
1332 Cysteine becomes essential in patients with Homocysteinurial.
1336 alpha keotacid dehydrogenase breaks down the branched chain amino acids and it requires all the co-factors used by a dehydrogenase. TLCFN
1339 Glucose loading decreases porphyrin synthesis by repressing ALA synthase activity, thus alleviating the abdominal pain and neuropsychiatric manifestations of Acute intermittent porphyria.
1340 Propionyl coA is derived from amino acids (Val, Ile, Met and Thr), odd numbered fatty acids, and cholesterol side chains. Congeintal deficiency of propionyl coA-carboxylase, the enzyme responsible for the conversion of propionyl coA to methylmalonyl coA, leads to the developement of propionic acidemia.
1341 catabolism of isoleucine, valine, threonine, methionine, cholesterol and odd-chain fatty acids leads to formation of propionic acid, which is then converted to methylmalonyic acid by biotin-dependent carboxylation. Isomerization of methylmalonyl coA forms succinyl coA, which enters the TCA cycle. Methylmalonyl coA is a isomerization reaction.
1342 alpha 1 mediated vasoconstriction prevents cerebral hypoperfusion upon standing. alpha blockers disrupt this mechanism and cause orthostatic hypotension.
1343 alpha 1 agonists increase both systolic and diastolic blood pressure via stimulation of alpha 1 adrenoreceptors in the vascular walls. Elevated systemic blood pressure is a/w a reflex increase in vagal influence on the heart. This results in decreased heart rate, contractility and conductance.
1344 Nitroglycerin can also increase heart rate. Furosemide decreases extracellular volume so can inmprove left ventricular function. Dobutamine increases cardiac output, myocardial oxygen consumption, contractility and conduction velocity.
1348 Mainstay therapy for acute mania is a mood stabilizing agent like Lithium, valproate or carbamazepine, plus an atypical antipsychotic (e.g. olazapine).
1350 splitting — thinking ppl are either all good or all bad. Hallmark of the borderline personality disorder.
1353 Narcotic/opiate withdrawal sx are typically described as flu-like. Opiate withdrawal is marked by abdominal pain, nausea, vomiting, diarrhea, piloerection, pupillary dialation, diaphoresis and fever. Cocaine withdrawal is marked by hypersomnolence, fatigue, depression, suicidality and strong cravings for cocaine.
1354 Net filtration pressure = (Pc-Pi)- (Pi c- Pi i).
1355 Glucose transport into cells is via means of facilitated diffusion with the help of transmembrane glucose transporter proteins (GLUT). These carrier proteins are steroselective and have preference for D-glucose.
1357 pc02 (normal 40) and Hc03 (normal 24). Respiratory acidosis occurs due to retention of co2 in the lungs and presents with a low pH and high Pc02. Metabolic acidosis develops due to depletion of Hc03 and is characterized by a low pH and a low HC03.
1359 sympathetic adrenergic nerve inputs inclue various organs, cardiac and smooth muscle, glands and nerve terminals). Sympathetic output to adrenals and sweats glands are via ACh.
1361 peripheral blood don’t have cholinergic innervation, but there are muscarinic receptors present on the enodthelial surface. Binding of cholinomimetic agents (muscarinic agonists) promotes release of NO aka EDRF. NO activates guanylate cyclase and increases cGMP. cGMP activates Calcium pump and causes calcium efflux from the cells. Decrease in calcium concentration causes vascular smooth muscle relaxation.
1362 Flushing, diaphoresis, nausea and decreased heart rate is due to cholinergics, which can be used to treat atonic bladder (non-obstructive urinary retention (postoperative ileus)).
1364 epinephrine works at a1,b1 and b2 receptors. a1 vasoconstriction causes increase in systolic pressure, b1 causes increased HR and b2 activation causes decrease in diastolic pressure. Increase in diastolic pressure can occur either via abolition of the vasodilator effects of B2 or the enhancement of the a1 vasoconstriction. Propranolol blocks b2 producing peripheral constriction without significantly increasing BP. B2 block leaves a1 vasoconstriction intact increasing diastoli
1366 Anaphylactic shock is characterized by vasodilation, increased vascular permeability and bronchoconstriction. Epinephrine counteracts these physiological mechanisms and is the drug of choice for the treatment of anaphylaxis.
1370 Ornithine transcarbamoylase deficiency is the most common disorder of the urea cycle, resulting in severe neurological abnormalities due to high blood and tissue ammonia levels. Accumulated carbamoyl phosphate is converted into orotic acid. Increased urine orotic acid excretion is typical.
1371 N-acetylglutamate is an essential activator of carbamyl phoshpate synthase I and is formed by the enzyme N-acetylglutamate synthetase from the precursors of acetyl-coA and glutamate.
1372 Ornithine transport into mitochondria is essential for urea formation, as ornithine is needed to combine with carbomoyl phosphate within the mitochondria to form citrulline in the second step of the urea cycle. Urea cycle defects cause neurological damage primarily due to the accumulation of ammonia. Protein restriction would improve this condition.
1376 Polycistronic viral specific mRNA contatining multiple cistrons, or genes, within the same mRNA transcript and produces a polyprotein product. For functional individual viral proteins to be generated, the polyprotein must be cleaved by a specific viral protease. This method of replication is demonstrated in the SS (+) linear, nonsegmented RNA viruses. A ss+ virus has a genome that is independently infective if transferred inot a host cell and that functions as its own mRNA.
1377 Ether and other organic solvents dissolve the lipid bilayer that makes up the outer viral envelope. Loss of infectivity after ether exposure is a characteristic feature of enveloped viruses.
1380 potassium ion conduction is highest during the repolarization phase of the action potential.
1382 In general, high potassium efflux and some sodium influx are responsible for the value of the resting potential, which is typically about -70 mV.
1384 Hypoxia induce hemolysis is seen in sickle cell anemia. Left shift of the hemoglobin curve results in hypoxia and reflex polycythemia.
1386 oxygen binding affinity increases as the P02 increases. Increased concentratio nof protons in tissues forms salt bridges that stabilize the deoxy form of hemoglobin and causes oxygen to be released, while protons attach themselves to the hemoglobin. In lungs oxygen attaches itself to the hemoglobin along with release of protons. Deoxyhemoglobin is stabilizing by ionic bonding of 2,3 DPG and by salt bridges between N-terminal histidine residues in each globulin.
1388 diphtheria infection is associated with a 3% mortality rate. Cardiomyopathy is the mcc of death. Treatment is passive immunization that includes diphtheria antitoxin, antibiotics (penicillin or erythromycin) and immunization. Of these, the antitoxin is the most imp and has greatest effect on prognosis.
1391 Listeria is a gram positive rod and shows a very narrow zone of beta-hemolysis on sheep agar, shows tumbling motility at 22 degrees and can be cultured at temp as low as 4 degrees. Intact cell-mediated immunity is essential for the elimination of Listeria monocytogenes from the body.
1393 Ampicillin is the choice of treatment for Listeria.
1395 Lecithinase/alpha toxin is main toxin produced by C.perfringens..degrades lecithin leading to membrane destruction, cell death and widespread necrosis and hemolysis.
1396 pseudomembranous colitis shows colonic mucosa with plaques composed of fibrin and inflammatory cells.
1397 C.diff toxin A attracts neutrophils to cause mucosal inflammation and diarrhea. Toxin B causes actin depolymerization, loss of cellular cytoskeleton integrity, cell death and mucosal necrosis.
1399 dysphagia, diplopia and dysphonia seen in botulism. Three main types of botulism: food-borne, wound botulism and infant botulism. They show normal conduction velocity but decreased compound muscle action potential.
1406 Auer rods are stained my myeloperoxidase, whereas immature lymphocytes, both B and t cells are stained with TdT.
1407 congenital hypothyroidism is present with hypotonia, poor feeding, jaundice, macroglossia, constipation and umbilical hernia.
1410 Rhinoviruses are acid-labile, whereas enteroviruses like Coxsackie A, echovirus, poliovirus and hep A virus are heat stable so can colonize the GI.
1413 The individual subunits of the hemoglobin molecule are strucutrally analogous to myoglobin. If separated, the subunits will demonstrate a hyperbolic oxygen-dissociation curve similar to that of myoglobin.
1416 Methhemoglobinemia causes dusky discoloration to the skin (similar to cyanosis) and anemia results since methhemoglobin can’t carry oxygen. blood partial pressure is measure of 0xygen dissolved in plasma and is normal in many disorders.
1420 As the mRNA sequence is translated in a 5′ to 3′ direction, these tRNA anticodons bind the complementary 3’to 5′ direction; thus, mRNA codons and tRNA anticodons are aligned in an antiparallel fashion. start codon of protein synthesis is 5′ to 3′ direction AUG and stop codons are UAG, UGA and UAA.
1421 FMR1 is located on teh long arm of X chromosome. An increased number of CGG trinucleotide repeats leads to hypermethylation of cytosine bases and subsequent gene inactivation. Manifests as mental retardation, facial dysmorphism and macroorchidism.
1422 campylobacter can be transmitted from domestic animals to humans
1423 Hypoalbuminemia and prolonged PT are signs of liver failure and indicate a poor prognosis. Alcohol liver injury deevelops through the stages of alcoholic steatosis, alcoholic hepatitis and cirrhosis. Increased AST and ALT are indicators of hepatocellular damage. Symptoms of alcoholic cirrhosis includes ascites , hepatomegaly and asterixis.
1424 Each tRNA molecule is specific for a given amino acid. Many tRNA anticodons can bind to a few diff codons coding for the same amino acid. This is called the wobble phenomenon.
1426 G6PD is an enzyme of the pentose phosphate pathway that in erythrocytes is essential for maintaining adequate concentrations of NADPH. Insufficient NADPH results in an inability to maintain gluathione in reduced state. This makes the cell more prone to oxidative stress such as hemolysis induced by infection, drugs and other oxidants.
1433 Conversion disorder: suggest a neurologic or medical illness. Sx include blindenss, aphonia, weakness, pseudoseizure, anesthesia, gait disturbance, diplopia and paralysis. Tends to affect young women and is often associated with an emotional stress. Somatization should include four pain sx, two GI, one sexual and one pseudoneurologic sx. Hypochondriasis is often seen in ppl with anxiety disorders.
1435 3′ to 5′ exonuclease activity of DNA poly III helps remove an improper base-pair nucloetide during replication. Endonuclease can remove groups of nucleotides (up to ten) at a time.
1437 multiple origins of replication make eukaryotic DNA synthesis quick and effective despite large sie of the genome compared to that of prokaryotes.
1439 characteristic triad of pulsus paradoxus: muffled heart sounds, jugular venous distension and hypotension During normal inspiration, the pressure in the pleural space and lung interstitium decreases, increasing pulmonary vascular capaciance. This results in a fall in venous inflow toe ht he left heart and a drop in cardiac output. Increased venous return to the right heart and an increased heart rate during inspiration tend to offset this decrease in cardiac output by increa
1441 CGD pts are at increased risk of infections from staph aureus, pseudomonas cepacia (Burkholderia cepacia), serratia maracens, nocardia spp and aspergillus spp.
1442 alzheimers dementia specific therapies include cholinesterase inhibitors (Donepezil), antioxidants (vitamin E) and NMDA receptor antagonists (eg. Memantine).
1445 N-acetylcysteine is a mucolytic agent that works by cleaving disulfide bonds within mucus glycoproteins, thus loosening thick sputum in cystic fibrosis.
1449 Absence of sertoli cells in a XY fetus results in development of both female and male internal genitalia along with normal male external genitalia due to normal Leydig cells. Sertoli cells contain mullerian inhibiting factor which cause involution of paramesonephric ducts.
1451 Pseudogout cyrstals are positively biregringent under polarizing light, blue when parallel and yelolow when aligned perpendicularly. This is opposite of the negatively birefringent monosodium urate crystals.
1453 General sensation (including pain, touch, pressure and temperature) from anterior 2/3rd of the tongue is via the mandibular branch of trigeminal (V2)
1457 liver uptake of unconjugated bilirubin is a passive process and secretion of conjugated bilirubin into bile canaliculi is an active process. When active diffusion is inhibited, conjugated bilrubin leaks into blood and is excreted in urine.
1460 obstructive sleep apnea = nocturnal hypoventilation. Risk factors are obesity, tonsillar hypertrophy and hypothyroidism.
1461 genetic recombination between two defective viruses co-infecting the same host cell can yield a cytopathic wild-type genome. Recombination is gene exchange that occurs through the crossing over of two double stranded DNA molecules. Reassortment describes the mixing of genome segments in two or more segmented viruses that infect the same host cell.
1465 Restlessness, agitation, and dysphagia progressing to coma 30 to 50 days following an exposure to cave bats is strongly suggestive of rabies encephalitis. Rabies is a killed vacine. Can have agitation, persistent fever, variable consciousness, and painful spasms with swallowing or inspiration.
1466 Killed or viral component vaccines generate a humoral immune response and produce neutralizing antibodies that impair viral attachment to host cells.
1467 When live polio vaccine is administered to mucosal surfaces, it promotes prolonged synthesis and secretion of local mucosal IgA than does a killed vaccine. This is not the case in killed polio vaccine so there is difference in duodenal IgA lvls
1472 Histone 1 located outside of the nucleosome core and helps to package nuclosomes inot more compact structures by binding and linking DNA between adjacent nucleosomes.
1473 Mitochondrial DNA is small circular molecules that resemble bacteria DNA and code for proteins, transfer RNA and ribosomal RNA.
1474 High dose irradiation results in double-strand DNA breaks and production of ree oxygen radicals.
1475 Base excision repair order – Glycosylase, endonuclease, lyase, DNA polymerase and ligase. Cytosine deamination creates unsual base uracil. Glycosylase cleaves the altered base leaving an AP site (Apurination or Apyrimidation). Endonuclease cleaves 5′ end and lyase cleaves the 3′ sugar phosphatre. DNA polymerase and ligase fill the single nucleotide gaps.
1476 3′–>5′ exonuclease is used for mismatch repair as in HNPCC. Endonuclease is non functional in Xeroderma pigmentosum.
1478 Glucose induced decreased adenylate cyclase activity leads to low intracellular concentrations of cAMP. Low cAMP lvls, in turn, cause poor binding of catabolite activator protein (CAP) to the CAP-DNA binding domain, leading to decreased expression of the structural genes of the lac operon.
1479 constitutive expression of the structural genes of the lac operon can occur with mutations in the gene for the repressor protein (LacI) or with mutations to the operator region, causing failure of the repressor to bind effectively to the operator.
1482 Transamination reactions occur beween an amino acid and alpha-keto acid. The amino group from amino acid is transferred to the a-keto acid, and the a-keto acid in turn becomes an amino acid. Pyridoxal phosphate (vit B6) serves as a cofactor in amino acid transamination and in decarboxylation reactions.
1484 tyrosine becomes essential in PKU pts.
1485 Bacterial mRNA can be polycistronic, meaning that one mRNA codes for several proteins. An example of polylcistronic mRNA is the bacterial lac operon, which codes for the proteins necessary for lactose metabolim by E.coli, the transcription and tranlation of these bacterial proteins (B-galactosidase and permease) is regulated by a single promoter, operator, and set of regulatory elements.
1489 insulin used to treat gestational diabetes for whom diet and light exercise have failed to control blood glucose lvls.
1490 Ebstein’s anomaly is characterized by apical displacement of the tricuspid valve leaflets, decreased right ventricular volume and atrialization of the right ventricle.
1492 Non selective Beta blockers mask the symptoms of hypoglycemia in diabetics. They exacerbate hypoglycemia and mask its adrenergic symtoms. B2 blockade inhibits hepatic gluconeogensis and peripheral glycogenolysis and lipolysis.
1495 blood group P antigen, globoside, is a parvovirus B19 receptor that is expressed on mature erythrocytes, erythroid progenitors, megakaryocytes, endothelial cells, placenta and fetal liver and heart. The virus is highly tropic for erythroid precursor cells and predominantly replicates in the bone marrow.
1498 adenovirus is the mcc of viral acute hemorrhagic cystitis outbreaks in children.
1500 Tetrahydrobiopterin is a cofactor used by hydroxylase enzymes in the synthesis of tyrosine, dopa, serotonin, as well as nitric oxide. Enzyme dihydrobiopterin reductase deficiency causes defective regeneration of BH4 and is an uncommon cause of PKU>
1501 In atypical phenylketonuria with tyrosine supplementation, only the catecholamine synthesis reactions downstream of tyrosine are compromised.
1506 sotalol has both beta-adrenergic blocking properties and class III arntiarrhythmic (K+ channel blocking) properties. It prolong both PR interval and the QT interval.
1508 QRS comples is ventricular depolarizatino which is phase 0, QT interval is ventricular repolarization which is pahase 3 of the cardiac action potential.
1510 Increased contractility increases the stroke volume of the pressure-volume loop.
1513 The cardiac action potential conductio velocity is slowest in the AV node and fastest in the purkinje system. The conductivity of the atrial muscle is higher than that of the ventricular muscle.
1514 CFTR protein is a transmembrane ATP-gated chloride channel.
1515 carotid massage increases baroreceptor firing and thus increases parasympathetic influence on the heart and vessels, and ultimately prolongs the AV node refractory period which stops AV re-entrant tachycardias. paroxysmal supraventricular tachycardia are typically a re-entrant circuit in the AV node. Episodes are usually treated with adenosine.
1519 at FRC, the intrapleural pressure is -5mmHg, but the airway pressure is 0mm Hg.
1520 Low frequency sound is best hearad at the apex of the cochlea near the helicotrema. High frequency sounds is best detected at the base of the cochlea near the oval and round windows.
1525 In gallstone ileus, gall stone enters through cholecystenteric fistula and gets stuck at the ileocecal valve. Gas is seen in the gallbladder and the biliary tree.
1526 PA02 = 150 – (PaC02/0.8) A-a gradient = PA02 – Pa02
1528 The low afterload pressures of pulmonary circulation allow the thin right ventricle to keep pace with the more substantial left ventricle. The rate of blood flow in both systemic and pulmonary circulation must be kept same. Only the arterial pressures and oxygen contents are different both at rest and during exercise.
1529 Fick principle is used to calculate the cardiac output. Cardiac output is equal to the oxygen consumption by the tissues divided by the arteriovenous oxygen difference.
1534 Neurofibromas are tumors of schwann cells, which are derived from the neural crest. they are skin-colored or pink colored nodules with rubbery texture and exhibit pathognomonic buttonholing.
1535 phrenic nerve carries pain info from the diaphragmatic and mediastinal pleura. Sensory innervation from the remainder of parietal pleura (includes costal and cervical pleura) is accomplished by intercostal nerves.
1537 look at this CT scan
1540 three cardinal signs of DKA is polyphagia, polydypsia and polyuria.
1542 P02 in the left atrium is lower than that in the pulmonary veins because deoxygenated blood from the bronchial arteries mixes with oxygenated blood in the pulmonary veins.
1543 Higher expiratory flow rates despite low lung volumes in restrictive lung diseases due to increased elastic recoil pressure and increased radial traction on the conducting airways by the fibrotic pulmonary interstitium. Even healthy lungs have radial traction on airway walls.
1544 acute salicylate intoxication results in acute respiratory alkalosis. High dose ingestion results in superimposed metabolic acidosis. Its a mixed disorder so you see both hypocarbia, low bicarbonate and low pH.
1547 Malabsorption present in chronic alcoholic pancreatitis due to the exocrine insufficiency
1548 mucus secreting cells are present to the lvl of the smallest bronchi. Cilia are present to the level of the terminal bronchioles.
1553 post-herpetic neuralgia is the most common neurological complication of vZV virus.
1556 RPF= PAH clearance = UV/P RBF= RPF/1- Hct
1557 S3 sound is a low frequency heart sound that can be physiologic in children but is typically pathologic in adults where it generally results from left ventricular failure or restrictive cardiomyopathy. The S3 sound can be accentuated by having the pt lie in the left lateral decubitus position and exhale fully.
1561 Neurophysin is produced within the cell bodies of teh paraventricular and supraoptic nuclei. They are released along with the hormones from axon terminals in the posterior pituitary gland.
1564 The tertiary amine physostigmine can reverse both the CNS and peripheral sx of severe atropine toxicity. The anticholinesterase agents neostigmine and edrophonium have a quaternary ammonium structure that limits CNS penetration.
1565 In pts with HTN and Chronic ischemic myocardial failure, ACE inhibitors are considered to be the most effective long-term treatment option as they inhibit myocardial remodeling and the associated deterioration of ventricular contractile function, in addition to reducing blood pressure.
1568 Isotretinoin is used to treat severe acne and its main adverse effects are hypertriglyceridemia and teratogenicity. Pregnancy is an abosolute contracindication to its use.
1569 White blood cell count in increased in both CML and leukemoid reactions so to differentiate between these two looka the alkaline phosphatase score.
1572 EBV is also associated with increased incidence of both Hodgkin’s and non-Hodgkin’s lymphomas as well as nasopharyngeal carcinoma.
1579 sepsis and shock are two major risk factors for ARDS ARDS produces non-cardiogenic pulmonary interstitial and intra-alveolar edema, inflammation and alveolar hyaline membranes
1581 chronic cholestasis from biliary obstruction can cause fat soluble vitamin malabsorption.
1582 Four major causes of hypoxemia (low Pa02): alveolar hypoventilation, ventilation-perfusion mismatch, diffusion impairment and right to left shunting. A-a gradient is normal in alveolar hypoventilation.
1583 PaC02 is the major stimulator of respiration in healthy ppl. In prolonged hypercapnia, high pac02 ceases to stimulate the respiratory drive. In such pts, respiration is stimulated by hypoxia (low Pa02) sensed by peripheral chemoreceptors. Rapid increases in the fraction of inspired oxygen may lead to respiratory failure in these pts. Pa02 is sensed by chemoreceptors in the carotid and aortic bodies.
1585 Pulmonary edema in LHF results in decreased lung compliance.
1586 erythrocytosis is defined as a hematocrit level >52% in males and >48% in females. A normal red blood cell mass indicates plasma volume contraction as the cause of polycythemia. polycythemia vera is a myeloproliferative disorder with low erythropoeitin levels, which secondary erythrocytosis such as COPD or hypoxia from high altitudes, smoking increases erythropoetin. A sa02<92% can cause seconadary polycythemia. Increase in RBC mass is absolute vs relative erythrocytosis.
1588 PAH is filtered at the glomerulus into Bowman’s space and is secreted by the proximal tubules via carrier-mediated organic acid active transport. PAH is not reabsorbed by any portion of the nephron so the lowest concentration of the PAH is in the bowman’s space.
1589 Exercise increases heart rate and CO but maintains normal Pa02 and PaC02. Carotid sinus massage causes a reflex vagal discharge to the sinoatrial node, atrial myocytes and AV node. The heart rate and cardiac output are transiently reduced and would not significantly affect the Pa02 or PaC02.
1590 During aerobic exercise, increased skeletal muscle CO2 production increases the PC02 of mixed venous blood. Homeostatic mechanisms maintain arterial blood gas levels and arterial pH near the resting values.
1591 Mitral stenosis elevates the LAEDP and PCWP relative to the LVEDP.
1592 Mononucleosis is most commonly see in CMV infections of immunocompetent pts. Retinitis is most common manifestation of CMV infection in pts who are HIV-positive.
1596 secretory IgA protects against giardia lamblia.
1598 caseating granulomas consist of large epithelioid macrophages with pale pink granular cytoplasm surrounding a central region of necrotic debris.
1600 Non inflammatory arthritis so can’t be rheumatoid arthritis. Reiters is associated with infections with campylobacter, shigella, salmonella, chlamydia or bartonella.
1605 Pts undergoing total gastrectomy require lifelong vitamin B12 supplementation which is a water soluble vitamin.
1606 1,25-dihidroxycholecalciferol is calcitriol, which is the active form of vit D.
1607 ADH primarily acts on the collecting ducts, increasing their permeability to water. In the presence of ADH, urine is most concentrated at ends of the collecting ducts. In the absence of ADH, tubular fluid is most concentrated at the junction between the descending and ascending limbs of loop of Henle.
1608 In presence of ADH, collecting duct contains the most concentrated urine in the nephron. Ascending limb of loop of henle and the distal tubules contain the most dilute urine.
1609 carotid body and sinus afferent nerve is glossopharyngeal. Aortic arch and body afferent nerve is vagus. Blood pressure increases or external pressure on the carotid sinuses stimulates the baroreceptors in the carotid sinus walls, leading to vasodilation, decrease in heart rate and contractility, and decrease in BP.
1610 Can get down syndrome from Trisomy 21, Unbalanced Robertsonian translocations and Mosaicism.
1613 GVHD occurs after allogeneic bone marrow transplantation, transplantation of organs rich in lymphocytes (such as liver), or transfusion of non-irradiated blood. Skin, liver and GI are generally the most affected targets of GVHD
1614 isotype switching occurs in the germinal centers.
1615 T4 can be converted in the peripheral tissues to the more active T3 or to the inactive rT3. T3 can’t be converted to rT3 or T4. Exogenous T3 administration causes decreased TSH levels, which act up on the thyroid gland to reduce endogenous T4 production (and thus peripheral conversion to rT3).
1616 The total resistance of the circuit is via 1/TPR = 1/R1 +1/R2 + 1/R3 + 1/Rn
1617 Get this image about the tubluar fluid/plasma ultrafiltrate.
1619 PAH is freely filtered from the blood in the glomerular capillaries to the tubular fluid in Bowman’s space. It is also secreted from the blood into the tubular fluid by the cells of the proximal tubule by a carrier protein-mediated process. The secretion of PAH can be saturated at high blood concentrations.
1620 Pulmonary vascular resistance is lowest at the functional residual capacity. Both inspiration and expiration increase the pressures in the pulmonary vasculature. During inspiration, alveoli expand and interstitial elastic tissue of lungs is put under tension. This exerts collapsing pressure and tension on the pulmonary vasculature. When air is exhaled, positive pressure is placed on the lungs by surrounding musculature resulting in compression of both airways and blood vessel
1625 A chronic AV fistula (shunt) would increase cardiac output because of increased sympathetic stimulation to the heart, increased venous return and decreased TPR. It would also cause the venous return curve to shift to the right because the circulation blood volume is increased by renal retention of fluids and venous return is increased by sympathetic tone.
1628 Rituximab is a monoclonal ab against the CD20 antigen. Improves the prognosis of some lymphoams.
1630 EBV genome is identified in 50% of systemic B-cell lymphomas and almost all primary CNS lymphomas occuring in the setting of HIV infection. A high mitotic index with proliferation fraction (ki-67 fraction) of >99% is typical of Burkitt lymphoma.
1631 All skin from the umbilicus down, including the anus (upto the dentate/pectinate line) but excluding the posterior calf, drains into the superficial inguinal lymph nodes. Prostate drains into internal iliac nodes, but also external iliac and sacral (minor pathways). Superior region of bladder drains into external iliac, whereas inferior region drains into the internal iliac. Lymph from sigmoid colon drains into inferior mesenteric lymph nodes.
1633 Prolonged exposure to loud noises causes hearing loss due to damage of the sterociliated hair cells of the organ of Corti.
1638 tibial nerve innervates the flexors of the lower leg, the extrinsic digital flexors of the toes and the skin of the sole of the foot.
1640 superomedial quadrant of the buttock contais the superior gluteal nerve.
1641 Cidofovir does not require conversion to nucleoside monophosphates. It is already a cidofovir and therefore requires only cellular kinases for conversion to the active nucleoside triphosphate form.
1644 pyrophosphate analog foscarnet is one of the few that do not require intracellular activation by viral or cellular kinases. Ganciclovir is a guanine nucleoside anologue requires intracellular conversion to its monophosphate form by virally encoded kinase.
1647 Neutropenia is significant adverse effect of ganciclovir therapy and its incidence is increased with coadministration of zidovudine. Both drugs can affect DNA synthesis in hematopoietic stem cells, resulting in bone marrow suppression.
1648 Oseltamivir is a nueraminidase inhibitor useful in treatment and prevention of both influenze A and B viral infections. It imparis the release of newly formed virions from infected host cells and impairs viral penetration of mucous secretions that overlie the respiratory epithelium.
1653 normal (adult) pressures in the cardiac chambers and pulmonary artery. Look at pic.
1655 sulfonyl ureas increase the rate of insulin secretion and C peptide lvls in pts with type 2 diabetes.
1657 progressive weakening diaphragmatic contractions during maximal voluntary ventilation with constant phrenic nerve stimulation during inspiration indicate neuromuscular junction pathology (eg decremental synaptic transmission) and/or abnormally rapid diaphragmatic muscle fatigue.
1662 Mallory-Weiss tears are due to repetitive vomiting which means metabolic alkalosis.
1663 Both hypocalcemia and resultant secondary hyperparathyroidism contribute to renal osteodystrophy.
1666 pts older thaan 65 are particularly prone to developing secondary bacterial pneumonia after influenza infection. In order, the pathogens most often responsible for secondary bacterial pneumonia are strep pneumo, staph aureus and H.influenzae.
1669 child with febrile maculopapular rash that begins on the face and spreads to include the trunk and extremeties is suggestive of Rubeola (measles) or Rubella. Postauricular and occipital lymphadenopathy are a/w Rubella.
1670 Tetrad of cough, coryza, conjunctivitis and Koplik spots (tiny white or blue-gray lesions on the buccal mucosa) that precede the maculopapular skin rash. Tetrad for measles.
1671 The DNA form of HIV genome includes structural and regulatory genes. Structural gene (gag, pol, and env) prodcuts include nucleocapsid proteins p24 and p7 (from the gag gene) and envelope glycoprotein gp120 and gp41 (from the env gene). Imp enzymes are produced from transcription and translation of the pol gene. The regulatory tat and rev genes are required for viral replication.
1672 In HIV cycle, polyprotein precursors are encoded by the structural genes (gag, pol and env). Only the env gene polyprotein is glycosylated to gp160 and proteolytically cleaved within the ER and Golgi to formt he envelope glycoproteins gp120 and gp41 that allows virus absorption by the target cells.
1673 HIV-1 protease inhibitors are strongly a/w medication-induced body fat redistribution syndrome, which is characterized by the redistribution of body fat from the extremities to the abdominal viscera and the subcutaneous adipose tissues of the thorax, posterior neck and supraclavicular region.
1675 Fusion inhibitors bind to HIV envelope transmembrane gp41 to prevent viral penetration in to the target cells.
1678 actinomyces israelli is a gram + best known for causing cervicofacial actinomycosis in pts following dental manipulation or other oral trauma. slowly growing and firm-feeling abscess in the face or neck region that eventually forms cutaneous sinus tracts. Long term penicillin treatmen and surgical debridement are required.
1679 Mycoplasma produces low grade fever and malaise and non productive cough. Chest x-ray suggests a severe pneumonia even though the pt appears relatively well. Mycoplasma require cholesterol supplementation in order to grow on artificial media.
1680 The proximal 1/3 of the ureter receives its blood supply from the branches of the renal artery.
1684 caudal regression syndrome – sacral agenesis causing lower extremity paralysis and urinary incontinence – commmonly a/w poorly controlled maternal diabetes.
1686 The recurrent layrngeal nerve travels in close approximation to the inferior thyroid artery and can be injured in surgical procedures of the anterior neck.
1687 clasp knife spasticity is characterized by initial jerking resistance to passive extension followed by sudden release of resistance. This is form of UMN lesion. CST, internal capsule (posterior limb), and primary motor cortex lesions can cause these sx.
1689 Wilson’s disease can cause cystic degeneartion of the putamen as well as damage to other basal ganglia structures. Putamen is located medial to the insula and lateral to the globus pallidus.
1691 the first arch develops mandible, malleus, incus, zygoma, vomer, palate, and temporal bone. It is a/w trigeminal nerve.
1692 Ankle jerk reflex is diminished in sciatica, which affects S1 nerve root.
1694 Deep branch of the radial nerve arises near the lateral epicondyle of the humerus, where the humerus articulates with the head of the radius.
1696 ACA occlusion causes weakness of the contralateral legs and sensory deficits of the contralateral legs, trunk and genitals. There also can be behavior and mood changes due to injury of frontal lobe structures.
1698 orbital floor is composed of a very thin layer of bone that separates teh orbit from the air-filled maxillary sinius.
1699 penetrating injury at the left sternal border in the fourth intercostal space would puncture the anterior surface of the heart. The right ventricle composes most of the heart’s anterior surface.
1701 Portal vein thrombosis causes portal hypertensiono and occurs distal to the liver, while leaving the liver unaffected.
1702 sternocledomastoid muscle originates on medial clavicle and manubrium and is innvervated by CN XI.
1705 Squatting improves the cyanosis because the resulting increase in systemic pressure reduces teh amount of right-to-left shunting through the VSD (decreasing the amount of blood bypassing the lungs). Tetraology of Fallot is the most common cause of cyanotic congenital heart disease. Tetralogy of Fallot, transposition of great vessels and truncus arteriosus are the three major cyanotic heart diseases that can be caused by abnormal migration of neural crest cells.
1707 Drugs that bind their receptors with a higher affinity or are able to gain access to their target tissues will have greater potency (lower ED50).
1709 bioavailability refers to the fraction of administered drug that reaches teh systemic circulation in a chemically unchanged form. F= (AUC oral * dose IV)/ (AUC IV * dose oral).
1710 Characteristics of drug such as high molecular weight, high plasma protein binding, high charge, and hydrophilicity tend to trap the drug in the plasma compartment resulting in low Vd (3-5L). Small molecular weight but hydrophilic, can distribute to interstinial fluid compartment and intravascular compartment reaching 14-16L. If both small molecular weight and uncharged (hydrophobic or llipophilic), the drug can reach intracellular compartment reaching Vd of 41 L.
1713 Oral administration subjects a drug to a large amount of first-pass metabolism, whereas IV, sublingual, and rectal administration bypasses some or all of this process and allows more drug to reach the systemic circulation.
1715 High lipophilicity , high Vd, good penetration into CNS are preferentially processed by liver into more polar compounds for easier elimination in bile and urine.
1716 in first-order kinetics, a constant fraction (of proportion) of drug is metabolized per unit time based on the serum concentration. In Zero-order kinetics, a constant amount of drug is metabolized per unit time, independent of concentration.
1720 Colony-stimulating factors, prolactin, growth hormones and cytokines utilize tyrosine kinase-associated receptors and the JAK/STAT signaling pathway. Look at the table from this q.
1722 Pol gene mutations are responsible for acquired resistance to HIV reverse transcriptase inhibitors and HIV protease inhibitors. Env gene mutations enable escape from host neutralizing antibodies.
1723 HIV infection increases the prevalence of HPV infection and the risk of anal carcinoma
1724 HIV pts often experience reactivation of latent EBV infections with resulting increased incidence of EBV-induces lymphoproliferative disorders including the aggressive non Hodgkin’s diffuse B-cell lymphomas.
1734 actin filaments are anchored to the Z-line of the sarcomere, which is an intracellular backbone.
1736 Ureteric bud gives rise to the collecting system of the kidney including the collecting ducts, minor and major calyces, the renal pelvis and the ureters. The metanephric mesoderm, however, gives rise to the glomerulus, Bowman’s space, the proximal tubule, loop of Henle, distal tubule and the collecting tubule.
1737 look up this CT scan of prostate.
1747 external branch of superior laryngeal nerve is at risk of injury during thyroidectomy due to its proximity to the superior thyroid artery and vein. The nerve innervates the cricothyroid muscle.
1751 Ductus arteriosus is derived from the sixth embryonic aortic arch. PDA can cause a thrill and a continuous murmur on the physical exam. PDA patency is required in cases of congenital heart disesae requiring a patent left to right shunt to maintain oxygenation such as in Tetralogy of Fallot and Transposition.
1753 Dysplasia ia reversible change. Once dysplasia has breached the basement membrane, then its not reversible anymore and is considered as a carcinoma.
1754 Reactive lymphoid hyperplasia is polyclonal, whereas malignant transformation is monoclonal. T cell receptor rearrangement is necessary for this monoclonality?
1755 c-myc is a nuclear phosphoprotein that functions as a transcription activator controlling cell proliferation, differentiation and apoptosis.
1758 overexpression of bcl-2 protein due to translocation of the bcl-2 oncogene from chromosome 18 to the Ig heavy chain locus on chr 14, results in inhibition of apoptosis and promotes survival of tumor cells.
1766 Proton pump inhibitors block the final common pathway of gastric acid secretion from parietal cells, which is stimulated by ach, histamine and gastrin.
1770 Best way to prevent neonatal tetanus is to ensure that all pregnant women have been vaccinated with the tetanus toxoid, to allow transfer of protective IgG antitoxin antibodies across the placena to the fetus.
1773 chronic systemic use of corticosteroids such as prednisone promotes osetoporsis and may cause fractures. Thought to promote osteoporsis by causing decreased synthesis of bone matrix, inhibition of the intestinal action of vit D in promoting calcium absorption, and increased PTH levels.
1774 isoniazid is directly hepatotoxic.
1776 combined use of non-dihydropyridine calcium channel blockers (eg. verapamil, dilitiazem) and B-adrenergic blockers (eg. atenolol) can have additive negative chronotropic effects yielding severe bradycardia and hypotension.
1779 Spore forming bacterial can survive boiling temperatures (100 C). These include bacillus and clostridium species.
1782 cardiogenic shock = pump failure. cardiac tamponade occurs when pericardial pressure exceeds 10mmHg. The force is sufficient to cause collapse of the atria, which results in an increase in systemic venous pressure, reduced ventricular preload and eventually decreased cardiac output.
1785 Pancytopenia in the absence of splenomegaly is characteristic of Aplastic anemia. Differential diagnoses include vitamin B12/folic acid deficiency anemia (megaloblastic anemia), aleukemic leukemia and myelodysplastic syndrome.
1786 Pure red cell aplasia can cause marked hypoplasia of marrow erythroid elements in the setting of normal granulopoiesis and thrombopoiesis. Pure red cell aplasia is associated with thymoma and parvovirus b19 infection.
1787 Aplastic anemia is characterized by pancytopenia, low reticulocyte count and absent splenomegaly
1796 adding iron to iron deficiency anemia pts will increase bone marrow erythropoeisis and results in accelerated release of reticulocytes, which contain bluish cytoplasm on Wright-Giemsa stain and reticular precipitates of residual ribosomal RNA
1797 Increased activity of microsomal monooxygenase enzyme makes pts more sussceptible to developing benzopyrene-induced lung cancer
1800 Leukotreine B4 and C5a stimulates neutrophil migration to the site of inflammation
1803 weakness of dorsiflexion (deep peroneal nerve) and weakness of eversion of foot (superficial peroneal nerve).
1804 The ureters cross over the common/external iliac vessels and under the gonadal vessels ( and ovarian vessels in the female). They pass lateral to the internal iliac vessels and medial to the gonadal vessels as they enter the true pelvis.
1806 Vit E deficiency occurs in individuals suffering from fat malabsorption or abetalipoproteinemia. Vit E serves to protect fatty acids from oxidation. Cells that are susceptible to oxidative damage are neurons with long axons. Vit E deficiency cause cause neuromuscular disease (eg, skeletal myopathy, spinocerebellar ataxia, pigmented retinopathy) and hemolytic anemia.
1807 B2 is phosphorylated to FMN and further phosphorylated to FAD, which are enzymes that participate in reduction-oxidation reactions within the human body. FMN is part of complex I, while FAD is part of comples II. FAD is an electron carrier in TCA cycle and serves as cofactor for succinate dehydrogenase, which converts succinate to fumarate.
1809 Primary amenorrhea in a pt with fully developed secondary sexual characteristics suggests the presence of an anatomic defect in the genital tract, such as imperforate hymen or Mullerian duct abnormalities.
1810 In most cases of monosomy X, the etiology is loss of parental X chromosome during mitosis; in the cases of otehr oforms of aneuploidy, the etiology is meitoic nondisjunction. Mosaicism arises secondary to mitotic errors after fertilization has taken place.
1812 Mastectomy is one of the most common causes of damage to long thoracic nerve cauing winged scapula and inability to raise the shoulder above horizontal.
1813 Middle meningeal artery is a branc of the maxillary artery which itself is a branch of the external carotid artery. Middle meningeal artery can be seen at the junction of frontal, parietal, temporal, and sphenoid bones.
1814 The vagus nerve provides some cutaneous sensation to the posterior external auditory canal via its small auricular branch. Sensation to teh rest of the canal is from CN V3. A vasovagal syncopal episode results from stimulation of the vagus nerve, leading to a decrease in blood pressure and heart rate.
1816 Sx of hemorrhagic cystitis include frequent urination, suprapubic pain, dysuria and hematuria. This can be prevented by mesna.
1818 Folinic acid is same as Leucovorin. Leucovorin, a 5 formyl-derivative of THF does not require the action of dihydrofolate reductase for its conversion to tetrahydrofolate.
1819 human multidrug resistance (MDR1) gene codes for P-glycoprotein, a transmembrane ATP-dependent efflux pump protein that has a broad specificity for hydrophobic compounds. This protein can both reduce the influx of drugs into the cytosol and can increase efflux from the cytosol, thereby preventing the action of chemotherapeutic agents.
1820 Aggressive hydration and amifostine should be utilized to prevent nephrotoxicity in pts receiving a platinum-based chemotherapeutic regimen (cisplatin).
1822 Trisomy 13 due to nondisjunction during maternal meiosis I. A/w cleft lip,palate, holoprosencephaly, polydactyly and rocker-bottom feet.
1823 Trisomy 18 (47 XX +18) has the presence of clenched hands with overlapping fingers. have rocker-bottom feet like in Patau’s. Have small jaws, small eyes and malformed low-set ears.
1826 somatic sensory innervation from anterior 2/3rd of tongue is via the V3. Taste sension from same region is CN VII. Both somatic sensory innervation and taster senastion is via CN IX.
1827 In congenital hydrocele, processus vaginalis remains patent, allowing fluid from the peritoneum to accumulate in the scrotum.
1828 Both Clopidogrel and aspirin inhibit platelet aggregation. Clopidogrel inhibits by blocking the surface ADP receptors essential for platelet activation, aggregation and fibrin binding. Both are efficacious in the prevention of thromboembolic disease.
1829 The lower trunk ultimately forms the median and the ulnar nerves which innervate the intrinsic muscles of the hand.
1830 In a complete mole, the sperm fertilizes the egg and replicates its own chromosomes while eliminating the maternal chromosomes. In partial mole, two sperm fertilize an ovum resulitng in 69 XXX or XXY.
1832 The third part of the duodenum crosses horizontally across the abdominal aorta and IVC at the L3. It lies in close association with uncinate process of the pancreas and the superior mesenteric vessels.
1833 Most highly oxygenated blood in fetus is carried by the umbilical vein, which empties directly into the IVC via the ductus venosus.
1835 A high synovial fluid wbc count (100,000/ul) and absent crystals suggest bacterial joint infection. Requires antibiotic treatment to prevent joint destruction, osteomyelitis and sepsis.
1836 Isoproterenol is agonist at both B1 and B2, and at lower doses, selectively binds to B2 receptors.
1838 With the exception of Vit B12, the body’s stores of most water-soluble vitamins are rapidly depleted without dietary intake. In contrast, hepatic stores of vit B12 may last up to several years. Severe vitamin K deficiency rarely results from poor dietary intake because colonic bacteria produce functional forms of vitamin K.
1841 ACE II causes systemic vasoconstriction, constriction of glomerular afferent arterioles and increases cortical aldosterone secretion.
1842 Acute chest syndrome, which is vaso-occlusive crisis localized to the pulmonary vasculature can occur in pts with sicke cell anemia
1843 Bulimia nervosa pts can develop bilateral partoid gland enlargment, erosion of tooth enamel and irregular menses.
1847 There is a salvage pathway using thymidine kinase that normally accounts for 5-10% of dTMP synthesis. Thymidine supplementation can moderately increased dTMP levels, it can reduce erytrhoid precursor cell apoptosis.
1848 Atrophic gastritis can result in profound hypochlorhydria, inadequate intrinsic factor production, vitamin B12 deficiency, megalosblastic anemia and elevated serum gastrin and methylmalonic acid levels.
1850 HSP is IgA mediated leukocytoclastic (hypersensitivity) vasculitis.
1851 Pentad of HUS involves thrombocytopenia, fever, renal failure, microangiopathic anemia and neurological symptoms
1852 sx of kawasaki include fever, bilateral conjunctivitis, lymphadenopathy and cutaneous involvement like oropharyngeal, peripheral extremities and generalized rash. Present with fever, bilateral conjunctivitis, cervical lymphadenopathy and mucocutaneous involvement.
1853 N.meningitidis virulence factors include a polysaccharide capsule that impairs phagocytosis of bacteria, LPS endotoxin, pili (for attachment of the respiratory mucosa) and IgA protease (cleaves secretory IgA). Antibodies to polysaccharides stimulate production of anticapsular antibodies. This protection is incomplete and transient.
1854 In type II arnold-chiari malformations, there is dilatation of ventricles. Hypertonicity and hyperreflexia result from upper motor neuron damage caused by stretching of the periventricular pyramidal tracts.
1855 Sickle cell anemia: Can get hemolysis, Vasooclusive sx like sickle cell dactylitis (hand and foot syndrome), pain crises, acute chest syndrome, leg ulceration, priapism, autosplenectomy and stroke. Infection are also caused due to asplenia.
1857 methotrexate competitively inhibits dihydrofolate reductase, which catalyzes the synthesis of tetrahydrofolate. Failure of dihydrofolate reductase causes the intermediate dihydrofolic acid polyglutamate to accumulate within treated cells.
1859 Erythroid precursors in liver and spleen – extramedullary hematopoiesis, condition characterized by erythropoeitin-stimulated, hyperplastic marrow cell invasion of extramedullary organs. Extramedullary hematopoiesis is most frequently caused by severe chronic hemolytic anemias, such as B-thalassemia.
1861 Triad of low hemoglobin, thrombocytopenia and absent hematopoietic cells in bone marrow is consistent with aplastic anemia.
1863 Acute hepatitis symptoms include anorexia, nausea, low-grade fever, bilirubinruia and right upper quadrant tenderness. Caused by Hep A in young adults. It causes hepatocyte ballooning degeneration and apoptosis.
1865 coarse erythrocyte basophilic stippling and microcytic hypochromic anemia are common peripheral blood smear findinds in lead poisoning. young children and industry workers are vulnerable to it.
1867 Biliary cirrhosis producing cholestasis is a potential cause of hypercholesterolemia leading to xanthelasma.
1869 Nicotinic receptors are present on postganglionic neurons in sympathetic and parasympathetic ganglia and on skeletal muscle cells at the NMJ. Drugs that block skeletal muscle nicotinic receptors are tubocurarine to induce paralysis.
1872 Integrin mediated adhesion of cells to basement membrane and the ECM involves the binding of integrins to fibronectin, collagen and laminin
1873 FGF and VEGF play a role in angiogenesis. FGF also plays a role in embryonic development, hematopoiesis and wound repair ( through the recruitment of macrophages, fibroblasts and endothelial cells to damaged tissues).
1874 during wound healing, excessive matrix metalloproteinase activity and myofibroblast accumulation in the wound margins can result in contracture. Contractures produce deformities of the wound.
1879 Factor V leiden mutation predisposes to deep vein thromboses, a source of most pulmonary emboli.
1886 carnitine deficiency impairs fatty acid transport into mitochondria, restricting ketone body production.
1887 Erythrocytes can’t convert ketones to acetyl coA due to lack of mitochondria. Liver cells can’t either since they lack the eznyme succinyl coA-acetoacetate coA transferase (thiophorase).
1889 Only the liver can utilize the glycerol produced by the degradation of triglycerides by hormone sensitive lipase. Glycerol in liver is used for triacylglycerol synthesis, gluconeogensis and as an intermidate in glycolysis. Adipose tissue synthesizes the glycerol phosphate needed for triacylglycerol synthesis from DHAP.
1890 6-mercaptopurine is degraded by xanthine oxidase. Both 6-mercaptopurine and 6-thioguanine are prodrugs that require activation by HGPRT.
1891 Cladribine is the doc for hairy cell leukemia. Cladribine is a purine analog that is resistant to degradation by adenosine deaminase. Adenosine deaminase serves in the purine disposal pathway and it degrades chemotherapeutic purine analogs, as well as adenosine. Cladribine is resistant to adenosine deaminase and penetrates well into the CNS.
1894 vincristine causes neurotoxicity.
1896 Parvovirus B19 causes arthritis in adults and fifth disease in children. This arthritis resolves by itself over time and local NSAIDs can treat the Sx.
1900 Lambert Eatons syndrome is a neuromuscular disorder presenting with proximal muscle weakness, cranial nerve involvement and autonomic symptoms. Approx half of pts have a malignancy (small-cell lung cancer)
1906 Enteroviruses are mcc of viral aspetic meningitis. The enterovirus group includes the coxsackievirus, echovirus and polioviruses. Poliovirus can cause LMN injury in addition to meningitis, especially in non-immunized individuals from endemic regions.
1908 Erythrocytic forms of malaria may be treated with chloroquine or mefloquine. Primaquine is required to kill P.vivax and P.ovale liver schizonts.
1919 Decreased DLCO in emphysema due to destruction of alveoli and adjoining capillary beds.
1924 flattening of the deltoid after a shoulder injury suggests anterior shoulder dislocation.
1926 breast milk lacks vitamin D and K.
1927 councilman bodies or apoptotic bodies are acidophilic and are found in pts with acute viral hepatitis.
1929 Gardnrella vaginosis — gray discharge an dfishy odor. shows clue cells, which are vaginal epithelial cells covered in small dakr particles (bacteria).
1931 Calcium efflux into sarcoplasmic reticulum during relaxation of muscle is achieved by the use of Ca2+ ATPase and Na/Ca2+ exchange mechanisms.
1933 Trochlear nerve palsy is characterized by vertical diplopia (double vision when eye looks towards the nose such as while reading a newspaper or climbing downstairs).
1935 Heteroplasmy describes the condition of having different organellar genomes (eg. mutated and wild type) within a single cell. For mitochondrial diseases, pts with more severe disease are those with a higher proportion of defective mitochondrial genomes within their cells.
1937 Chronic lymphedema predisposes to angiosarcoma development.
1938 VIP increases intestinal chloride loss into the stool, which causes excess losses of the accompanying water, sodium and postassium as well. VIP also inhibits gastric acid secretion. Somatostain is used to treat VIPoma.
1940 In beta thalassemia minor, mutations affecting the transcription, processing and translation of mRNA lead to a deficiency of beta-globin chains.
1942 COPD can cause hypoxia sufficient to stimulate increased erythropoietin production by cortical cells of the kidney.
1944 carvedilol nonspecifically antagonizes B1 and B2 adrenergic receptors as well as alpha 1 adrenergic receptors. Beta blockers and carvedilol in particular, have been shown to slow the progression of heart failure and reduce all-cause mortality in pts with CHF. Beta-adrenergic blockers decrease cardiac work by slowing the ventricular rate and decreasing afterload.
1945 exophthalmos is due to increased soft tissue mass wihtin the bony orbit, which results from enlargement of the extraocular muscles and increased fibroblast proliferation and ground substance production. Exophthalmos does not typically improve with beta-blocker therapy. Beta blockers are frequently used to treat the acute sx of thyrotoxicosis in preparation for thyroid surgery.
1946 essential tremor is the most common movement disorder. Pts experience slowly progressive symmetric postural and/or kinetic tremor that commonly affects upper extremities. Essential tremor is inherited via AD fashion. First line Rx is propanalol
1948 B1 blocker inhibits renin release from JG cells.
1949 Gonococcal urethritis causes dysuria and copious, purulent, yello-green urethral discharge. Gram stain of this discharge show neutrophils with gram negative intracellular diplococci. Coinfection with chlamydia is common in these pts so azithromycin should be given in addition to ceftriaxone in pts with acute gonococcal urethritis.
1950 Chlamydia trachomatis lacks peptidoglycan within the cell wall. It also prodces penicillin-binding proteins.So they are not effective against penicillins and cephalosporins.
1951 Nafcillin is commonly used empirically to treat skin and soft tissue infections (e.g folliculitis, abscesses) for which S.aureus is the usual cause.
1952 D-Ala-D-Ala is the amino acid sequence on peptidoglycan precursor molecules that is recognized by the enzyme transpeptidase. Penicillins are structural analogs of D-Ala-D-Ala that inhibit this enzyme by binding covalenty to its active site. The result is failed synthesis of the bacterial peptidoglycan cell wall.
1954 ITP should be suspected when you thrombocytopenia with ecchymoses, petechiae and mucosal bleeding without symptoms of TTP/HUS, pancytopenia, marrow failure or splenomegaly.
1955 broca’s area is the caudal part of the inferior frontral gyrus of the dominant hemisphere (usually left).
1958 Gardnella Vaginalis – clue cells on wet mount microscopy of the discharge.
1960 most common metastatic tumors to the brain are lung cancer, breast cancer and melanoma.
1965 Chloroquine is effective in eradicating chloroquine-sensitive plasmodia from the bloodstream, but has no activity against the latent hepatic infections established by P.vivax and P.ovale. Primaquine must be used in addition to completely eradicated infections by these organisms and prevent replapses. Primaquine is not active against the erythrocytic forms of plasmodia, including trophozoites.
1966 Enteroviruses, including coxsackievirus and echovirus are the most common causes of aseptic meningitis. In viral meningitis, wbc count <500 cells/ul and lymphocytic predominance. In bacterial meningitis wbc count >1000 cells/ul and neutrophilic predominance.
1967 saphenous vein is below the pubic tubercle
1972 prokaryotic 16s rRNA sequence is found in 30s ribosomal subunit. 16S rRNA contains a sequence complementary to the shine-dalgarno sequence on mRNA.
1973 Verapamil is a calcium channel blocker that slows SA and AV node phase 0 depolarization. (In nodal cells, this phase of depolarization is mediated by calcium ion influx). Phase 0 depoloarization of the cardiac conduction system occurs during diastole; thus, verapamil slows diastolic depoloarization.
1975 Adenosine and acetylcholine act on the phase 4 of the nodal cell action potential reducing the rate of spontaneous depolarization in cardiac pacemaker cells. Adenosine activates K+ channels, inhibits L-type Calcium channels prolonging the time taken to reach threshold.
1979 When the steady state PaC02 persists above teh range given by Winter’s formula of PaC02 = 1.5*(Hco2) +8 +/- 2, the pt has a superimposed degree of respiratory acidosis and failure.
1981 pulmonary embolism leads to hypoxemia, which leads to hyperventilation.
1983 A holosystolic murmur that increases in intensity on inspiration most likely represents tricuspid regurgitation. The other holosystolic murmurs (which are secondary to mitral regurgitation or ventricular septal defect) do not typically increase in intensity during inspiration.
1985 Prolonged, untreated obstructive sleep apnea can also cause pulmonary hypertension and right heart failure.
1987 high circulating levels of estrogen and progesterone prevent lactogenesis while also promoting breast growth and development during pregnancy.
1989 Fabry disease, inherited deficiency of alpha-galactosidase A. In Fabry disease pts, ceramid trihexoside accumulates in tissues. Earliest manifestations are angiokeratomas, hypohidrosis and acroparaesthesia. Without enzyme replacement, pts typically develop progressive renal failure.
1994 PABA esters are widely used UVB radiation absorbers. However, they do not significantly absorb or block radiation in the UVA wavelength range.
1995 SCID can also show absent thymic shadow (thymic hypoplasia).
1996 HbA1c is glycosylated hemoglobin in diabetics. HbA1 is a2b2, HbA2 is a2d2, HbF is a2g2. In B-thalassemia minor, there is increase in HbA2 cuz beta chains are not produced.
1998 Oragnophosphate poisoning is treated with muscarinic antagonists like atropine in addition to pralidoxime (PAM), a cholinesterase enzyme reactivator.
1999 Reserpine blocks the storage of adrenergic mediators in presynaptic vesicles. This reduces the synaptic cleft concentration of NE. Reserpine also predisposes to depression because it depletes NE and serotonin from the presynaptic vesicles.
2001 Cocaine intoxication causes agitation, dramatic symmetric pupillary dilation that remains responsive to light, tachycardia, and blood pressure elevation. Both cocaine and tricyclic antidepressants inhibit neurotransmitter reuptake in adrenergic synapses.
2005 CHF drugs are positive inotropes like digoxin, beta blockers, ACE inhibitors and loop diuretics. Of these, loop diuretics cause hypokalemia. K+ sparing diuretics are spironalactone, amiloride and triamterene. Potassium sparing diuretics act on the collecting duct of the kidney tubule.
2006 Beta blockers slow AV conduction which causes PR interval prolongation. Pts with long QT syndrome have increased risk of Torsade de pointes (twisting of points), a form of ventricular tachycardia. Long QT syndrome can be congenital or drug-induced. Antiarrhythmics like quinidine and sotalol are a/w acquired long QT.
2007 Deflection of membrane potential to near zero would indicate an increase in permeability to ions with equal and opposite equilibrium potentials, such as sodium and potassium.
2008 Acid exretion in urine in DKA pts occurs in teh form of free hydrogen ions and titratable acids (NH4 or H2Po4). During metabolic acidosis, excretion of free H+ and titratable acids increases, excretion of Hc03 decreases, and urinary pH decreases.
2009 The heart is perfused during diastole and consumes about 5% of the cardiac output. The myocardial oxygen requirement is very high. Coronary flow is regulated by local metabolic factors, including hypoxia and adenosine accumuation. Blood returning from systemic circulation via the pulmonary artery has more oxygen remaining than does coronary venous blood. The heart has the highest oxygen requirements of any tissue or organ in teh body.
2011 Excretion rate = total filtration rate – tubular reabsorption rate.
2012 vasopressin acting on V2 receptor increases permeability to water and urea at the inner medullary collecting duct. This increases urea reabsorption and decreases in the fractional excretion of urea and decrease in renal clearance of urea from plasma.
2013 In secondary hyperaldosteronism, both renin and aldosterone levels are elevated. Causes include renovascular hypertension associated with fibromuscular dysplasia or atherosclerosi. Diuretic use, malignant HTN and renin-secreting tumors are also causes.
2016 SER contains enzymes for steroid and phospholipid biosynthesis. All steroid producing cells (adrenals, gonads, liver) contain a well-developed SER).
2018 etoposide inhibits topoisomerase II
2019 AZT (Zidovudine) doesnt have 3′-OH group , preventing a 5′ to 3′ phosphodiester linkage. AZT along with inhibiting reverse transcriptase, incorporates inot the viral genome as a thymidine analog. Inhibits chain elongation which is replicating DNA by phosphodiester linkage.
2022 spleens forms from mesodermal dorsal mesentery. splenic artery that supplies the spleen is a branch of teh celiac trunk .
2024 V3- runs through foramen ovale. V2 runs through the foramen rotundum. Meningeal branch of V3 runs through foramen spinosum along with meddile meningeal artery and vein.
2025 Two promoter regions where RNA polymerase II and transcription factors are the TATA aka Hogness box located 25 bp upstream, and CAAT box located 70-80 bases upstream of the gene. Enhancers increased the rate of transcriptiojn initiation through protein binding and interactions with transcription factors bound to promoter sequences. Enhancers/repressors may be located anywhere upsttream, downstream or even within the trascribed gene.
2026 hydrogen bonds are the principal stabilizing force for the secondary structure of proteins.
2029 Releasing factors recognize the stop codons (UAA, UAG and UGA) to terminate protein synthesis.
2030 TATA box is a promoter region that binds transcription factors and RNA poly II during the initiation of transcription. It is located approx 25 bases upstream from beginning of the coding region.
2031 In expression cloning, where signals necessary for transcription and translation are included in the cloned DNA, the gene is incorporated into a plasmid and translated into protein. This protein is then able to bind to a DNA probe. Proteins that can bind DNA are transcription factors, steroids, thyroid proteins, vit D receptors, retinoic acid receptors, DNA transcription and replication proteins.
2033 Poly-A tails are not transcribed from the DNA template by the poly-A polymerase. A consensus sequence “AAUAAA” directs the addition of the poly-A tail onto the mRNA.
2035 cytoplasmic P bodies play an imp role in mRNA trascription regulation and mRNA degradation.
2037 tRNA has dihydrouracil, thymidine and acetylcytosine residues and has CCA at the 3′ end of this molecule. The anticodon arm contains sequences which are complementary to the mRNA codon and is read in the 3′ to 5′ direction.
2038 Mutation of splice sites result in the formation of larger proteins that are usually nonfunctional but often retain the immunoreactivity of the normal protein (binding to antibodies)
2039 RNA poly I- rRNA RNA poly II – mRNA RNA poly III – tRNA
2040 carrier status for sicke cell anemia can be established by hemoglobin electrophoresis.
2044 Southwestern blotting is used to detect DNA-binding proteins, such as transcription factors, nucleases, histones etc. Jun is a DNA-binding protein.
2046 delusional disorder– a single overriding delusion and relatively preserved occupatoinal and social functioning, while not meeting the diagnostic criteria for schizophrenia.
2050 Bulimia nervosa is binge eating disorder that is either restrictive or purging compensatory behaviors. Bulimia and anorexia are distinguised by body weight and absence or presence of amenorrhea. Depressed mood is common post-binge. Typical bingeing (eating whole cakes) and compensatory behaviors include purging (laxatives, enema, self induce vomiting) and non purging (exercise and fasting).
2052 Altruism is a mature defense mechanism that alleviates guilty feelings through selfless service or giving.
2054 Support involves expressing concern independent of understanding. This is contrast to empathy, where physician expresses understanding and vicarious experiencing of a pt’s situation.
2055 Bingle alcohol consumption (holiday heart syndrome) precipitate Atrial fibrillation which is most common chronic arrhythmia and presents are irregularly irregular tachyarrhythmia on physical examination. There are absent P waves in Atrial fibrillation.
2057 Minors can consent to treatment for pregnancy, sexually transmitted disease, birth control and drug or alcohol addiction without parental consent or notification.
2058 Blood alcohol lvls above 100mg/dl (0.10% BAC) tend to result in intoxication, slurred speech and impaired decision-making capacity. Pts who are temporarily incapacitated should not be allowed to make imp health care decisions.
2063 clinical manifestations of schizophrenia include hallucinations, delusions, disorganized thought, and negative sx (blunted affect, social withdrawal and anhedonia). Schizophreniform lasts from one to six months. below one month is brief psychotic disorder.
2064 type III hyperlipoproteinemia is characterized by Xanthomas and premature coronary and peripheral vascular disease. Defects are in ApoE3 and ApoE4, apolipoproteins found on chylomicrons and VLDL that are responsible for binding hepatic apolipoprotein receptors. ApoA-1 : lcat activation (cholesterol esterification). ApoB48-chylmoicron assembly and secretion by intesine..look at this Q.
2065 Pemphigus vulgaris — painful flaccid bullae and erosions of skin and ucosal membranes — oral mucosa is the most common place. Bullae spread laterally wiht pressure (Asboe-Hansen sign) and with gentle traction (Nikolsky sign).
2067 In deno purine synthesis, the activity of the PRPP amidotransferase is increased. This is also increased in Lesch-Nyhan syndrome to make up for the lost purines in uric acid production.
2068 Tryptase is alose released by mast cell degranulation and is often used as a marker of mast cell activation.
2069 Degranulation of mast cells is accomplished by cross-linking of multiple membrane-bound IgE antibodies by a specific antigen, resulting in IgE-Fc receptor aggregation on the cell surface.
2078 Pts with SCID present with recurrent infections caused by bacteria, viruses, fungi and opportunistic pathogens. Recurrent infection dont’ happen in cystic fibrosis.
2084 Sickle cell disease is characterized by repeated splenic infarctions that ultimately result in splenic atrophy or asplenia, which predisposes them to infections with encapsulated bacterium.
2085 Patients with chronic hemolytic anemia are predisposed to folic acid deficiency and macrocytic changes due to increased erythrocyte turnover.
2086 The kozak sequence on eukaryotic mRNA plays a role in the initiation of translation. A mutation of three bases upstream from the start codon (AUG) in this sequence is a/w thalassemia intermedia. Purine (A or G) positioned three bases upstream from AUG is a key factor in initiation process. A mutation in this causes impairment in mRNA binding to ribosomes.
2088 serotonin syndrome Sx include neuromuscular excitation (hyperreflexia, myoclonus and rigidity), autonomic stimulation (hyperthermia, tachycardia, diaphoresis and tremor) and altered mental status (agitation and confusion).
2089 cyproheptadine is an antihistamine with anti-serotonergic properties that can be used in the treatment of the serotonin syndrome.
2090 Gout can increase in frequency in pts with mutations in PRPP synthease due to increased production of purines, which results in hyperuricemia.
2091 colchicine inhibits chemotaxis of neutrophils by preventing microtubule formation. Neutrophils are primary cell responsible for the intense inflammatory response in pts due to phagocytosis of the monosodium urate crystals.
2093 HER2/neu oncogene encodes a 185-kD transmembrane glycoprotein that has intracellular tyrosine kinase activity and is a member of the family of epidermal growth factor receptors. Overexpression of this protein is associated with increased rates of breast and ovarian cancer.
2094 Polycystic ovarian syndrome (Stein-Leventhal syndrome) is clinically characterized by obesity, hyperandrogenism, oligomenorrhea, infertility, and elarged ovaries with mutliple cysts.
2095 clomiphene is used to treat Polycystic ovarian syndrome. Clomiphene is a selective estrogen receptor modulator that prevents negative feedback inhibition on the hypothalamus by circulating estrogen.
2101 Lactic acidosis occurs in pts with cardiac decompensation, respiratory or hepatic failure, septic shock and tissue infarction. In most of these conditions, impaired tissue oxygenation decreases oxidative pohosphorylation, leading to the shunting of pyruvate to lactate after glycolysis.
2102 Elderly pt with dementia, hemiparesis and dependent lung consolidation likely has aspiraion pneumonia becuase the opacities are located in the superior regions of the lower lobes (dependent positions) in supine individuals.
2107 S4 is a low frequency sound heard at the end of diastole just before S1 that is often a/w restrictive cardiomyopathy and left ventricular hypertrophy.
2110 penicillins and cephalosporins function by bindin to penicillin binding proteins such as transpeptidase.
2111 cephalosporin resistance is via change in structure of penicillin binding proteins.
2112 during continuous infusion of adrug metabolized by first-order kinetics, teh steady state concentration is reached in 4-5 half lives.
2118 If delta G is negative, Keq will be >1, and the concentration of products at equilibrium exceeds that of substrates. If delta G is positive, Keq will be less than 1, and teh formation of substrates will be favored.
2123 Acute stress disorder and PTSD share same sx but the timeline differs. Acute stress disorder is less than 4 weeks, whereas PTSD is more than 4 weeks.
2124 The coronary sinus communicates freely with the right atrium and therefore may become dilated secondary to any factor that causes right atrial dilatation. The most common such factor is pulmonary artery hypertension, which leads to elevated right heart pressures.
2125 trigeminal nerve arises at the level of the middle cerebellar peduncle in the pons.
2126 Non pupil sparing third nerve palsy is affected by aneurysm arising from either ipsilateral posterior cerebral artery or the superior cerebellar artery. Sx include unilateral headache, eye pain, diplopia, dilated nonreactive pupil, and ptosis with the ipsilateral eye in a down and out position.
2127 get the picture from his question.
2128 omalizumab is an anti-IgE antibody that has shown to be effective in reducing dependency on both oral and inhaled steroids.
2129 look at CT scan to idenfiy the mammillary body.
2131 Idiopathic membranous glomerulonephritis associated with circulating IgG4 antibodies to the PLA2(phospholipase A2) receptor.
2132 antithrombin inhibits factor Xa. Both unfractionated heparin and LMWH can bind to antithrombin to increase its activity against Factor Xa. Only unfractionated heparin is able to bind to both antithrombin and thrombin to allow antithrombin to inactivate thrombin.
2133 Fondaparinux are factor Xa inhibitors that increase PT and PTT levels but not the TT (thrombin time) levels.
7707 BRAF is a protein kinase involved in activation of signalling pathways for melanocyte proliferation and the BRAF v600E mutation is seen in 40-60% of pts with melanoma.
7710 H.pylori causes duodenal ulcers and is in greatest concentration in the prepyloric area of the gastric antrum.
7721 Wet age-related macular degeneration is due to increased vascular endothelial growth factor (VEGF) causing angiogenesis. AMD is classified as dry (subretinal drusen deposits or pigment chagnes) or wet (abnormal vessels with subretinal fluid/hemorrhage, gray subretinal membrane or neovascularization). Dry AMD-gradual vision loss in one or both eyes and progresses to more common wet AMD with acute vision loss.
7767 General policy should be not to accept gifts from pts, but exceptions like one time token cookies is ok.
7791 Genomic imprinting is produced by DNA methylation, which is an epigenetic process in which genes can be silenced by the attachment of methyl groups to cytosine residues in DNA molecule.

Please follow and like us:

Leave a Reply

Your email address will not be published. Required fields are marked *