Step1_qbank_self_assesment Flashcards
ARDS is characterize by what?
Acute lung dysfuntion, pulmonary edema, normal left arterial pressure, and a PaO2/FIO2 <200
ARDS is caused by:_____
injury to endothelial cells lining the pulmonary capillaries - ajacent to the alveoli [2/2 inflammatory cytokines and neutrophils]
Which fibers are located interatrial septum near the tricuspid orafice
Purkinhe System
Bone tumor associated with Paget’s disease
Osteosarcoma
Globus hystericus
“lump in th throat sensation”; tiggered by emotions
Which vitamin can pregnant women NOT have? Why?
Vitamin A; It is lipid oluble –> not readily excreted in urine –> accumulates in stellate cells of the liver; RESULT: fetal micro encephaly, cardiac anomalies, early epiphyseal closure, growth retardation, spontaneous abortion
Drug that inhibits acetylcholin-like muscarinic agents?
Atropine
Drug that potentiates acetylcholin-like muscarinic agents?
physostigmine
[Drug tox] confusion, blurred vision, dry mucus membranes, intense thirst
atropine [anticholinergic]
Cadherins
Ca2+ dependent transmebrane protein that participate in desmosome formation via homologous interaction with cadherins on ajoining cells –DO NOT participate int hemidesmosome fuction
Molluscum contagiosum
Poxvirus; characterised by multiple firm, flesh colored, dome-shapped papules on skin and mucus membranes; pruritic and have umbilicated centers containing white curd like material
What triggers bicarb-rich fluid accumulation in the duodenum?
Low pH of the duodenal content; pH pancrase promopted (by secretin) to secrete bicarb-rich fluid –> neutralized the hydrogen atoms in chyme
What is most commonly injured in anterior or postrior knee dislocations?
Tibial artery
Most common organism responsible for Endometritis?
Bacteroides species
Normal activity of tyrosine kinase receptor
transient dimerization;
In erectile dysfuntion, Phosphodiesterase-5 inhibitors (sildenafil) promot rection through the relaxation of which tissues?
vinus sinus smooth muscle within the corpora cavernosa
Which tissues produce bicarb inresponse to stimulation? (2)
exocrine pancrease and epithelial cells of the biliary tract
What mediates bicarb secretion
Secretin (released by S cells)
DiGeorge syndrome is assoicated with failed development of_____?
3rd and 4th pharengeal pouches (predecessors of the thymus, parathyroids glands, and ultimobranchial body) –> defective T cell immunity (2/2 abscent/hypoplastic thymus)
Androgen inensitivity
X-linked; 46XY; Female phenotype; absence of testosterone receptors; testosterone levels are high; LH levels are high (2/2 hypothalamic-pituitary gland resistance to androgen feedback); FSH is normal; EVENTUALLY circulating androgens ar econverted to estradiol –> breast development etc. /// BLIND VAGINA//// wolffian and mullerian structures are absent
Mullerian agenesis
primary ammenorrhea; NO UTERUS, NO fallopian tubes, and proximal vaginal fails to develop; LH and FSH increased; estorgen leaves
Major cause of brain injury in the pre-mature infant? Where does it start?
Intraventricular hemorrhage; germial matrix
Side effect Cisplatin (tox)
hearing loss 2/2 damage to hair cells in the cochlear membranous labyrinth
Side effect of Amiodarone
delayed onset interstital pneumonitis (in isolation)
Side effect of Procainamide
delayed onset pleuritis (assoc. drug induced SLE)
Misoprostal is a ___analog that binds to ____.
PGE1 analog; binds to plasma membrane prostaglandin receptors
Misoprostal effect on upper GI tract
stimulate gastric epithelial cell mucus production AND decrease paretal cell acid secretion
Palmitoylation
process in which FATTY acids covalently acnchor to plasma membrane cyctein residues —> increasing hydrophobicity of tail
Nitoglycerine effect on HR? on end-systolic volume?
Increase HR; decrease end systolic volume
Whch bugs cause Impetigo
Staph a. and Group A strep
Which cell synthesize Androgen-binding protien (ABP)?
Sertoli cells (of the seminiferous epithelium)
What does Androgen-binding protein do?
maintains the high local concentration of testosterone needed for normal sperm production and maturation
Glucagon acts through which type of intracellular protein?
Gs-protein
Epinephrine acts through which type of intracellular protein?
beta 2 receptor
Sweat is mediated by what? Affected by damage to which structure?
cholinergic postganglionic fibers of the sympathetic nervous system; thoracic sympathetic trunk
Acid-base imbalance with suspected PE?
hypoxemia and resp. alk [increase pH and decreased PaCO2)
Rapid vancomycin infusion leads to ___ and why?
Red man syndrome; wide spread release of histamin from mast cells
What is Platelet Activating factor?
phospholipid inflammatory mediator that causes severe broncoconstriction, vasoconstriction, and platelet aggregation with microthrombus formation
Platelest activating factor at low concetrations
vasodilator –> leukocyte adhesion to endothelium, diapedesis (transmigration), degranulation and oxidative bursts
What produces platelet activating factor?
platelets, basophils, mast cells, neutrophils, monocytes, macrophages, and endothelial cells
Through which receptors doe platlet activating factor affect platelets
G protein-couple receptor (Gq) –> activates phospolipase C (PLC) –> generated inosotol triphosphate (IP3) and diacylglycerol from memebran proteins
IP3 mediated release of Ca2+ [ER] does what to platelets
promotes activation
Pulmonary Hypertension Pathogenesis
(1) injury to the pulmonary ENDOthelium 2/2 to an idiopathic mechanism/medical condition; (2) NARROWing of pulmonary vascular bed –> RVH; (3) vascular injury 2/2 to increased PA pressure; (4) INCREAse RV afterload; (5) DILATE the RV
osterogenesis imperfecta asscoc. with mutation in which genes?
COL1A1 and COL1A2
In a state of starvation, what happens biochemically
(1) decrease insulin and increase glucagon –> mobilize stored energy; (2) Glycogen degraded in the first 24hr of fast; (3) gluconeogenesis –> glucose formed from metabolic intermediates (glycerol, lactate, and alpha-ketoacids <–TG break down); (4) Blood level of ketone bodies increase w/in first few days of fast
Absenece of which enzyme impairs ketone formation
medium chain Acyl-CoA dehydrogenase
beta-oxidation –> ketone bodies
(1) catalyzed by acyl CoA dehydrogenase –> removal of 2C (acetyl-CoA) from fatty acids –> When the amount exceeds the capacity of the TCA cycle –> excess acetyl-CoA in shunted into the production of ketone bodies
What is Ras and how does it function?
GTP-bindng, signal oncoprotein; involved in signal transmission from cell membrane to nucleus
Bile salts efect on small intestin bacteria?
microbucudak emulsifying agents - disrupt the outer membranes of gram neg. eneric bacili
Oranism tht has a haploid genome and an inner and outer cell membran, but NO nuclear membrane - sensitive to some penicillin ABx
Gram neg rod
Eukaryote contain equimolar amounts of 18S and 28S rRNA molecule, explain.
Both rRNA molecules are transcribed from a single chromosom as a single trascript that subsequently under goes cleavage
[Diabetic drugs] Insulin (lispro, aspar, glulisine/regular/NPH/ glargine, detemir)
Bind insulin receptor (tyrosine kinase actvity); Liver: increase glucose stored as glycoogen; muscle: increase glycogen and protein synthesis, K uptake; Fat: aid TG storage
[Diabetic drugs] Biguanides (metformin)
Decrease gluconenogenesis; increase glycolysis; increase periferal glucose uptake (insulin sensitivity)
[Diabetic drugs] Sulfnylureas (tolbutamide, chlorpropamide/ glybiride, glimepiride, glipizide)
Close K+ channel in beta-ccell membrane –> cell depolarizes –> tigger insulin release via Ca2+ influx
[Diabetic drugs] Glitazones/ thiazolidinediones (pioglitazone, rosigiltazone)
Increase insulin sensitivity in periferal tissue; bind PPAR-y nuclear transcrition regulator
[Diabetic drugs] alpha-glucosidase inhibitors ( acarbose, miglitol)
Inhibit intestinal brush border a-glucosidases; Delayed sugar hydrolysis and glucose absorbtion –> decreased postprandial hyperglycemia
[Diabetic drugs] Amylin analogs (pramlintide)
decrease glucagon
[Diabetic drugs] GLP-1 analogs (exentide, liraglutide)
increase insulin; decrease glucagon release
[Diabetic drugs] DPP-4 inhibitors (linagliptin, saxagliptin, sitagliptan)
increase insulin; decrease glucagon release
What is cimetidine’s (p 450 inhibitor) affect on warfarin metabolism? What happens to the PT?
slows metabolism; gradual increase og PT (over a period of days)
P-450 Inducers (+) [8]
Modafinil; Barbituates; St. John’s Wart; Phenytoin; Rifampin; Griseofulvin; Carbamazepine; Chronic alcohol use
P-450 Inhibitors (-)
Macrolides; Amiodarne; Grapefruit juice; Isoniazid; Cimetidine; Ritonavir; Acute alcohol abuse; Ciprofloxacin; Ketoconazole; Sulfanamide; Gemfibrozil; Quinidine
cAMP effect on borncial smooth muscle cells
relax 2/2 inhibition of myosin phosphorylation and lowering intracellular calcium concentration
osteomalacia (vita D deficiency) is characterized by deposition of which bone type?
excessive unmineralized osteoid matrix bone
Characteristics of Papvaviridae DNA viruses (papillomaviruses and polymaviruses
Repicate w/in the host cell nucleus utilizing host vell DNA and RNA polymerases
Characteristic of Poxviruses (DNA)
DO NOT replicate in the host cell
Historlogy of Hashimotos thyroiditis
intesne lymphocytic iniltration of the thyroid gland –> folicular destruction and germinal center formation
Which nerves are unmylenated? And what are they responsible for?
[Efferent] Autonomic postganglionic nerve; [***Afferent] “primary sensory” - slow pain, heat sensation, and olfaction
Which family do enteroviruses belong to? What do they commonly cause?
picornaviridae - positive ssRNA; aseptic meningitis
Examples of Enteroviruses?
poliovirus, coxackie A & B, echovirus, enterovirus, HepA
Which HLA class II compnent s digested by macrophages during antigen processing?
Invarient Chain
What is highly suggestive of insulin resistance
Elevated baseline insulin (in the setting of normoglycemia)
The Marfan and homocystinuria similarity can be explained by what genetic process?
Geneteic Heterogeneity –mutations of different genes cause similar phenotypes
How many ATP for every NADH
3 ATP
How many ATP for every FADH2
2 ATP
How many ATP for every GTP
1 ATP
Anaerobic glycolysis and glycolysis in erythrocyte generate how many ATP per glucose molecule metabolized? Why?
2 ATP; erythrocytes lack mitochondria
How many ATP are generated by aerobic metabolims of 1 molecule of glucose by the TCA cycle?
38 ATP
How do triazole funtion?
Inhibit ergosterol synthesis; * ergosterol is an essential lipid in the fungal cell memebrane*
Reiter Syndrome triad
(1) conjunctivitis; (2) urethritis; (3) seronegative arthritis
Cardiac hypertrophy is characteried by what?
Increased rate of myosin mRNA synthesis
PCOS is characterised by a decrease in which hormone?
FSH
What typer of regulatory protein dictates differentiation of a progenitor cell into a dermal cell?
Transcription factors
What drug/drug class can cause pupillary constriction in the denervated eye?
pilocapine; direct muscarinic cholinergic agonists
What causes pernicious anemia?
immune-mediated destruction of gastric mucosa –> atrophic gastritis (loss of intrensic factor secreting parietal cells) –>hypochlorhydria –> increased serum GASTRIN –> anemia, icterus, fatigue, atrophic glossitis, paresthesias, weakness, unsteady gait
Long term continuous leuprolide does what to male LH and testosterone production?
Inhibits LH release –> inhibits testosterone production
Charachteristics of DiGeorge syndrome [22q11]:
thymic aplasia, parathyroid aplasia, cardiac and great vessel defects (TRUNCUS ARTERIOUSUS > tet. F. > interupted aortic arch)
Defect expression of CD40 impairs what process?
Isotype switching
Naive mature B cells produce which Ig molecules?
IgM and IgD
DNA methylation affect of gene transcription
silences gene trascription
Gaucher’s disease
*MC lysosomal storage disease - mutation of glucocerebrosidase chr 1q21; GLUCOCEREBROSIDE deposition in lysosomes of macrophages (normally it would have been degraded into its basic glucose and lipid elements - by glucocerebrosidase) –“wrinkle tissue paper” macrophages
Clinical menifestations of Gaucher’s disease
Hepatomegaly, anemia, throbocytopenia, bleeding, osteopenia, bone pain, bone fractures
Name the anti-TNF-alpha agents
Infliximab (monoclonal AB to TNF-alpha) and Etanerept (recombinant TNF receptor fusion protein)
How does aspirin function?
Irriversibly inhibits COX 1 (also COX 2) –> thereby limiting thromboxain (TXA2) production in platelets –> decrease platelet aggregation and thrombus formation
[fetal circulation] ductus arteriosus function:
shunt blood from the pulmonay artery to the proximal descending aorta
[fetal circulation] foramen ovale function:
allows blood to pass from the right atrium directly into the left atrium — bypassing the lungs
[fetal circulation] ductus venosus function:
blood from the placenta flows through the umbilical vein into the liver –> blood goes throu hepatic sinusoids OR divered to the IVC by the ductus venosus
Define transformation.
process by which bacteria take up naked DNA from their environment and incoperate it into their genomes
Define Transduction.
bacteriophage-mediated tranfer of genetic information; NOT inhibited by DNAse
Define function of transposons
mediate the transfer of geneticinformation within a bacterium from one location of the genome to another
What is Homebox genes’ function?
guiding morphogenes
What is the result of mutation in HoxA-13
hand-foot-genital (HFG) syndrome
Effects of 1,25 dihydroxycholecaliferol ingestion (2)
(1) Increase Ca2+ and Increase Phos; (2) enhance bone resoption and bone storage of Ca2+ and Phos
Lesion in the MCA affect on vision
homonymous hemianopsia
Intraabdominal malignancies involve which lymph nodes?
Supreaclavicular
Decreasing which parameter will increase contraction velocity in isolated skeletal muscle?
Afterload
What kind of diarrhea does Giardia bring?
Watery - malabsorbtive
The following are signs of what: fatigue, decreased exercise tolerence, conjunctival pallor, white patches on gigival and buccal mucosa, hemorrages and bilateral exudates (fundoscopic); no palapable lymphadenopathy or organomegaly
acute leukemia
What do you expect to see on periferal blood smear in acute leukemia?
Blast cells
Virulence factor for Aspergillus
Vascular invasion
Virulence factor Strep pneumoniae
Polysaccharide capsule
Virulence factor H. Flu
Polysaccharide capsule
Virulence factor N. meningitidis
Polysaccharide capsule
Virulence factor mycobacterial organisms
Lipid rich cell wall
Effect of portal hypertension on the spleen
Congestion –> red pulp expansion
Treatment for esophageal variceal hemorrhage
Octreotide (somatostatin); reduces splanchnic blood flow and divert blood from the portal system –> systemic circulation –> splanchinic vasoconstriction [2/2 inhibition of hormones that produce splanchnic vasodilation – glucagon, and VIP]
