NBME CBSE 200 QUESTIONS AND ANSWERS CBSE LATEST (Recent Exam)

Chagas Disease ---------- Correct Answer -------- Caused by Trypanosoma cruzi parasite passed in the feces of Reduviidae/kissing bug Penetrates broken skin or intact mucous membranes forming a pseudocyst releasing inflammatory infiltrates into myocytes; stains with Giemsa & Wright Romana sign occurs when portal of entry is the conjunctiva or eyelid May resulting in: Enlarged heart- CHF, sudden cardiac arrest Enlarged esophagus- difficulty swallowing Enlarged colon- abdominal pain or constipation Treat with benznidazole or nifurtimox Monocytes ---------- Correct Answer -------- cell with half-moon shaped nucleus that participates in phagocytosis Chronic graft rejection ---------- Correct Answer -------- multifactorial but typically involves arteriosclerosis HLA-B27 ---------- Correct Answer -------- PAIR: Psoriasis Ankylosing spondylitis- chronic synovitis destroying cartilage typically in young men Inflammatory bowel dz- Crohn's & UC Reactive Arthritis- Reactive Arthritis ---------- Correct Answer -------- Arthritis as a reaction to a bacterial infection such as Campylobacter, Chlamydia, Salmonella, Shigella, or Ureaplasma. Associated with conjunctivitis & uveitis Gaucher (Type 1) ---------- Correct Answer -------- AR Lysosomal storage disease Accumulation of sphingolipid glucocerebroside Most common Wrinkled tissue paper I Cell disease ---------- Correct Answer -------- Failure of Golgi apparatus to phosphorylate mannose 6-phosphate the marker to export enzymes to lysosomes resulting in accumulation of lysosomal enzymes in serum Nitroblue tetrazolium test ---------- Correct Answer -------- Aqualitative test to determine defects in NADPH oxidase Negative: CGD Positive: Acute Hepatitis, Mono CGD (chronic granulomatous disease) ---------- Correct Answer -------- inability to produce NADPH oxidase; susceptible to Cat + organisms; elevated neutrophils w/ normal T cell Gp91 phox subunit: heme binding subunit of superoxide generating NADPH Treat with interferon gamma Clarithromycin (macrolide) ---------- Correct Answer -------- ADR of metallic taste & GI Codeine ---------- Correct Answer -------- ADR resp. depression, euphoria, & constipation Cyclobenzaprine ---------- Correct Answer -------- Structurally similar to TCAs w/ anticholinergic side effects used for relief of muscle spasms May exacerbate glaucoma Naproxen ---------- Correct Answer -------- ADR of GI & renal (in elderly) Timolol ---------- Correct Answer -------- Used in HTN & glaucoma; ADR of bradycardia & worsening asthma Bacterial vaginosis ---------- Correct Answer -------- Sloughed mucosal cells = clue cells Trichomoniasis ---------- Correct Answer -------- Cilated, motile trophozoites w/ corkscrew-like motility Autism ---------- Correct Answer -------- Lack of eye contact, verbal communication, & separation anxiety; repetitious behavior Emphysema ---------- Correct Answer -------- Decreased FEV1/FVC ratio, normal FVC; TLC, FRC, & RV increase Parathyroid hormone(PTH) vs phosphate in hypercalcemia ---------- Correct Answer -------- PTH: rapid & direct Phosphate: slow & indirect ANP: ---------- Correct Answer -------- Afib, Ch-1p, NPPA gene mutation causing binding interference,- decrease cGMP Failure of development of 3rd or 4th pharyngeal pouches ---------- Correct Answer -------- DiGeorge syndrome (CATCH 22): truncus arteriosus & agenesis of parathyroid glands May also be associated w/ failure of thymus to develop - T lymphocytes w/ CD3 marker Huntington disease ---------- Correct Answer -------- PCR is the most common method to est. # of CAGs Both the coding & template strands bind the forward & reverse primers on 3' end Pyrmidine Dimers ---------- Correct Answer -------- BRAF gain of function mutation causing covalant thymine (or Cystine) bonds normally repaired thru NER in the G1 phase by endonuclease recognition then excision (DNA polymerase then fills; ligase then reseals) Xeroderma pigmentosum ---------- Correct Answer -------- Mutation of NER endonuclease from UV radiation disrupting DNA replication due to the oligonucleotides remaining damaged DNA Polymerase I ---------- Correct Answer -------- Removal of both leading & lagging RNA primers 5' to 3' (unique) Proofreading of mismatch nucleotides via 3' to 5' exonuclease & elongation of lagging strand 5' to 3' (universal) Topoisomerase ---------- Correct Answer -------- Enzyme that functions in DNA replication, helping to relieve strain in the double helix ahead of the replication fork. Teniposide ---------- Correct Answer -------- Topoisomerase II inhibitor acting in the S phase & G2 phase: S phase: prevents proper unwinding of supercoils & reannealing of DNA G phase: Permanent breaks in both strands of DNA preventing transcription & repair inducing cell cycle arrest Cytarabine ---------- Correct Answer -------- Antimetabolite inhibiting DNA polymerase, arresting cells solely in S phase Fluoroquinolones ( -floxacin) ---------- Correct Answer -------- Bactercidal: direct inhibition of topoisomerase 2 & 4 halting DNA replication as 1st line treatment of uncomplicated pyelonephritis; older for gram negative & aerobic, newer more broad spectrum Contraindicated in LQTS with ADR of torn achilles Long QT syndrome ---------- Correct Answer -------- Rare inborn heart condition in which delayed repolarization of the heart following a heartbeat increases the risk of episodes of torsade de pointes and other life threatening arrhythmias. Prolongation of the QT interval is a diagnostic of the condition. KCNQ1 and KCNE1 Romano-Ward syndrome ---------- Correct Answer -------- AD inherited congenital long QT syndrome No deafness Increased risk for SCD due to Torsades (polymorphic ventiruclar tachycardia) Jervell and Lange-Nielsen syndrome ---------- Correct Answer -------- AR inherited congenital long QT syndrome with congenital sensoneural deafness Increased risk for SCD due to Torsades Telemorase ---------- Correct Answer -------- Carries its own RNA template at 3' for prevention during DNA replication Salicylate (Aspirin) toxicity ---------- Correct Answer -------- Mixed acid base disorder with: Early phase respiratory alkalosis, low PaCO2 Late phase metabolic acidosis, low HCO3 Normal pH Increased conversion of acteyl-CoA to ketoacids & pyruvate to lactate Lung adenocarcinoma ---------- Correct Answer -------- Peripheral glandular tumor with mucin & papillary components; biopsy for efficacy of therapy Presents in young, female, nonsmokers, with signet ring, EML4-ALK or EGFR & KRAS Signet Ring ---------- Correct Answer -------- Cell with a large vacuole, seen predominantly in carcinomas. Most frequently associated with stomach cancer, but can arise from prostate, bladder, gallbladder, breast, colon, ovarian stroma and testis Scalded Skin Syndrome ---------- Correct Answer -------- S. Aureus release of exofoliative toxin A causing desmosomal keratinocyte cleavage in S. Granulosum Causing B. Impetigo: Nikolsky positive blistering brown rash with flaccid bullae that easily slough off Pemphigus Vulgaris ---------- Correct Answer -------- Cancer Anorexia- Cachexia syndrome ---------- Correct Answer -------- 3 part MOA resulting in decreased calorie intake & hypermetabolic state resulting in significant weight loss 1. Cytokines IL-1, IL-6, INF-y, & TNF-a stimulate NfKb that activates ubiquitin proteasome pathway 2. TNF-a also mediates appetite suppression 3. Lipase activation causes reduction of body fat Ubiquitin-proteasome pathway ---------- Correct Answer -------- Myosin chains undergo degradation increasing catabolism Isosorbide Mononitrate ---------- Correct Answer -------- Unlike other nitrates does NOT undergo 1st pass metabolism by the liver w/ nearly 100% bioavailability, providing means of oral treatment for preventation of angina by CAD thru dephosphorylation of myosin light chains Itraconazole (Sporanox) ---------- Correct Answer -------- Antifungal that inhibits synthesis of ergosterol; metabolized by CYP450