Key Associations 1 Flashcards
1
Q
Location of stratified squamous epithelium in the respiratory tract
A
oropharynx, laryngopharnyx, anterior epiglottis, upper half of posterior epiglottis and vocal folds (TRUE VOCAL CORDS)
1
Q
Location of pseudostratified, columnar, mucus-secreting epithelium in the respiratory tract
A
Nose, paranasal sinuses, nasopharynx, most of larynx, tracheobronchial tree
2
Q
Most common cause of mitral stenosis
A
Prior rheumatic carditis
3
Q
Most common cause of fetal hydronephrosis (most common site of obstruction)
A
Inadequate recanalization of the URETOPELVIC JUNCTION between kidney and ureter, ureters are fully canalized before metanephros begins to produce urine (8-10th week of gestation)
4
Q
Mechanism of transient hydronephorsis ?
A
METANEPHROS begins producing urine before canalization of the URETERIC BUD is complete
5
Q
Fetal development of geintourinary tract develops from these structures
A
Pronephros (4th week), Mesonephros (4th week, wolffian duct, male GU), Metanephros (5-6th week, collecting duct, calices, renal pelvis, ureturs, renal parenchyma)
6
Q
Most prominent finding in neonate or fetus with Turner sydnrome
A
LYMPHEDEMA, ranging in severity from edema of the hands and feet to hydrops fetalis
7
Q
MC cause Acute viral hepatitis in young adults
A
HAV
8
Q
Filtration Fraction
A
Equal to GFR/RPF, typically 125/600 or 0.15 to 0.20, about 1/5 of total plasma that passes through glomerular capillaries
9
Q
Effect of hypovolemia on FF
A
FF is equal to GFR/RPF, so GFR↓/RPF ↓↓ causes increased FF due to compensation on GFR
10
Q
GFR
A
Volume of fluid filtered from renal glomerular capillaries into Bowman’s capsule per unit time, approximately 125 ml/min
11
Q
RPF
A
Volue of plasma delivered to kideny per unit time, approximately 600-700 ml/min
12
Q
When is Base excision repair needed?
A
Corrects defects in single bases induced spontaneously or by exogenous chemicals (nitrates in diet that deaminate cytosine, adenine, and guanine to uracil, xanthine, hypoxanthine)
13
Q
Explain mechaism of Base excision repair
A
GLYCOSYLASES remove defective bases -> Corresponding sugar-phosphate is removed by ENDONUCLEASE (cleaves 5’ end) -> LYASE cleaves 3’ end of sugar phosphate -> DNA POLYMERASE replases missing nucleotide -> LIGASE reconnects DNA strand
14
Q
4 Mechanisms that cause DNA damage
A
- Depurination of DNA and BER (spontaneous or chemical) 2. Formation of thymine dimers (UV) 3. Breaks in DNA chains and oxidative damage (ionizing radiation) 4. Cross-linkage, intercalation, alkylation (chemical/pharmacologic agents)
15
Q
MC etiological agent responsibe for shigellosis in the US and industrialized nations
A
Shigela sonnei (~80%), other species include dysenteriae, flexneri, boydii
16
Q
Mechanism by which Shigella initiates infection
A
Invades GI mucosa by exhibiting specificty for M (microfold) CELLS lie in base of mucosal villi within PEYER’s PATCHES in the ileum through ENDOCYTOSIS -> lyses endosome, multiplies, spreads laterally into other epithelial cells, causing death and ulcerat
17
Q
Bacillary angiomatosis, cat-scratch disease, culture-negative endocarditis
A
Bartonella henselae
18
Q
Where is Propionyl CoA derived from?
A
Amino acids (Val, Ile, Met, and Thr), odd-numbered fatty acids, cholesterol side chains
19
Q
Propionyl CoA carboxylase
A
Enzyme responsible for conversion of propionyl CoA to methylmalonyl Coa, leads to development of proionic acidemia
20
Q
MC cause of primary hyperparathyroidism
A
1 Parathyroid adenoma (80-85%),#2 Hyperplasia (10-15%)
21
Q
“Marble bone disease”
A
Osteopetrosis (decreased osteoclastic bone resporption)
22
Q
Hypokalemia will increase toxic effects of this drug
A
Digoxin
23
Q
Cytokines that downregulate local cytokine production and inflammatory reactions
A
IL-10 and TGF-beta
24
Metyrapone testing
Inhibits 11-beta-hydroxylase -\> 11 deoxycortisol does not cause feedback inhibition on ACTH so there is an ACTH SURGE and 11-deoxycortisol metabolites are measurable in urine as 17-hodroxy-corticosteroids. This means normal HPA axis.
25
3 factors that mediate angioedema by increasing vasodilitation and vascular permeability
Bradykinin, C3a, and C5a
26
Ultrasound reveals male and female. Which type of twin placentation is likely present?
Dizygotic twins result from fertilization of 2 oocytes by 2 different sperm and ALWAYS have 2 AMNIONS and 2 CHORIONS (Di-Di)
27
Structural genes in HIV
gag - nucleocapsid proteins p24 and p7, pol - reverse transcriptase, integrase, protease, env - envelope glycoproteins gp120 and gp41
28
Regulatory genes in HIV
tat and rev genes required for viral replication
29
Family and structure of HIV genome
Lentivirus subgroup of retroviruses, diploid genome consists of single-stranded, positive-sense RNA
30
Principle source of energy after 12-18 hours of fasting
gluconeogenesis (initial committed step involves conversion of pyruvate to oxaloacetate, and oxaloacetate to PEP
31
Mechanism of injury in HBV infection
Presence of viral HBsAG and HBcAg on cell surface stimulate host's cytotoxic CD8+ T lymphocytes to destroy infected hepatocytes
32
Mutation of K-ras proto-ncogene
Unregulated cell proliferation - responsible for size increases in adenomatous polyps
33
Mutation responsible for emergence of small adenomatous polyps from normal colonic mucosa
APC mutation - first step of the adenoma-to-carcinoma sequence.
34
Stage of gametogenesis for primary oocytes?
Completely developed by 5 months gestational age, arrested in PROPHASE of MEIOSIS I
35
Stage of gametogenesis for secondary oocytes?
At puberty, FSH stimulates oocytes to complete meisosis I, ovulation occurs and secondary oocytes are arrested in METAPHASE of MEIOSIS II
36
Predominant mechanism of heart failure in restrictive cardiomyopathy
DIASTOLIC dysfunction - reduced LV compliance (=dV/dP)
37
Predominant mechanism of heart failure in dilated cardiomyopathy
SYSTOLIC dysfunction
38
Causes of dilated cardiology?
Viral myocarditis, alcohol toxicity, diphthertic myocarditis, doxorubicin cause DILATED myopathy and SYSTOLIC dysfunction
39
Amyloidosis causes what type of heart dysfunction?
Restrictive cardiomyopathy, a DIASTOLIC dysfunction resulting from decrease in diastolic LV compliance
40
Orotic aciduria
Disorder of de novo pyrimidine synthesis (inability to convert orotic acid to uridine monophosphate (UMP) - hypochromic megaloblastic anemia, neurologic abnormalities, growth retardation and excretion of high amounts of orotic acid in the urine. Doesn't i
41
Defective ezyme in orotic aciduria
Orotic acid phosphoribosyltransferase or orotidine 5' phosphate decarboxylase (convert orotate to UMP) Rx: Uridine
42
Compare the rate of metabolism of Fructose, Galactose, Mannose
Dietary fructose is phosphorylated in the liver to F-1-P and RAPIDLY METABOLIZED because it bypasses PFK-1, the RLE of glycolysis. Other sugars enter glycolysis before the RLE and are metabolized more slowly due to regulation of PFK-1
43
Where does Galactose enter glycolysis?
Conversion to glucose-1-phosphate -\> Glucose-6-Phosphate before PFK-1
44
Where does mannose enter glycolysis?
Converted to fructose-6-phosphate, entering just before PFK-1
45
Where does fructose enter glycolysis?
Frutose is phosphorylated in liver by fructokinase -\> F1P -\> Aldolase B converts F1P to DHAP and glyceraldehyde -\> DHAP converted to G3P entering glycolysis after PFK-1 (rapidly metabolised)
46
$ How do certain strains of Diphtheria cause an acute toxin-mediated disease?
Non-pathogenic Corynebacterium Diphtheriae can cause severe pseudomembranous pharyngitis after acquiring the Tox gene via lysogenization by a temperate bacteriophage, permiting production of the exotoxin (potent exotoxin inhibits protein synthesis via ADP
47
Corynebacterium diphtheriae
ABCDEFG: ADP ribosylation, Beta-prophage, Corynebacterium, Diphtheria, Elongation Factor 2, Granules
48
2 major substances that drive angiogenesis
Vascular endothelial growth factor (VEGF) and FIBROBLAST GROWTH FACTOR (FGF) - FGF-2 causes promotion of endothelial cell proliferation, migration and differentiation. Lamin in BM may pose physical barrier to sprouting of new blood vessels.
49
What is Somatomedin C?
Insulin-like growth fctor I (IGF-1) synthesized by GH-influenced hepatocytes and stimlates cell growth and multiplication.
50
Complications of prematurity (\<1500 g)
RDS, PDA, Bronchopulmonary dysplasia, Intraventricular hemorrhage, Necrotizing enterocolitis, Retinopathy of prematurity. Almost always occurs within the first 5 postnatal days.
51
Transference
the unconscious shifting of emotions or desires associated with one persone (sibling, parent, spouse) to another (physician, therapist). Can be positive or negative
52
Projection
Attributing one's own unacceptable thoughts and feelings to another person.
53
Lingual thyroid
Thyroid fails to migrate downward and forms in the TONGUE, along thyroglossal duct's path. Surgeons should be careful when removing any mass along the thyroglossal duct's path, as the mass could be the only thyroid tissue present in the patient!
54
Defective migration is responsible for these disorders
Lingual thyroid, Kallmann's syndrome - failure of GnRH-secreting neurons to migrate from olfactory lobes to hypothalamus. Cryptorchidism - failure testes to migrate from intra-abdominal location to scrotum
55
Testicular venous drainiage
Right testicular vein drains directly into the IVC and the LEFT testicular vein drains into the LEFT RENAL VEIN
56
Stable angina results from:
fixed atherosclerotic coronary obstruction without superimposed thrombus
57
Unstable angina or subendocardial infarction result from:
Ulcerated atherosclerotic plaque with partially obstructive thrombus
58
Transmural MI results from:
Ruptured atherosclerotic plaque with a fully obstructive thrombus
59
t(11;14)
Mantle cell lymphoma, B-cell malignancy, translocation results in activation of cyclin D gene
60
t(8;14)
Burkitt lymphoma, c-myc protooncogene moved from 8 to 14, adjacent to gene for immunoglobulin heavy chain -\> increases frequency with which Ig gene is transcribed
61
Deletion of 13q
one of the molecular defects seen in CLL
62
t(8;21) Peroxidase positive
M2, AML with maturation, auer rods present
63
Pathogenesis of Polymyositis
Autoimmune presenting with symmetric proximal muscle weakness; CD8+ LYMPHOCYTE-mediated skeletal muscle damage
64
Degenerate
More than one codon can code for a particular aa (more codons (61) than amino acids (20)
65
Wobble
Many tRNA anticodons can bind to a few different codons coding for the same amino acid
66
Top 2 causes of UTIs in sexually active women
#1 E. coli (80%) #2 Staphylococcus saprophyticus
67
Most common pathogen causing cystitis and acute pyelonephritis
E. coli
68
Common drug interactions implicated in serotonin syndrome
ANTIDEPRESANTS (SSRIs, SNRIs, MOAIs, TCAs) Analgesics (Tramadol), Ani=emetics (5-HT3 receptor antagonists, ondansetron), ANTIBIOTICS - LINEZOLID, Triptans
69
Symptoms of serotonin syndrome
NEUROMUSCULAR EXCITATION: Hyperreflexia, clonus, myoclonus, rigidity, AUTONOMIC STIMULATION: hyperthermia, tachycardia, diaphoresis, and tremor, ALTERED MENTAL STATUS: Agitation and confusion
70
Contraindicated with serotonergic drugs
Analgesic tramadol, antiemetic ondansetron, and antibiotic LINEZOLID (a week monoamine oxidase inhibitor) used for serious gram (+), used concomitantly with other serotonergic drugs can precipitate serotonin syndrome
71
Main pulmonary symptom in Goodpasture
Hemoptysis - lung histology shows focal necrosis of alveolar walls and intra-alveolar hemorrhages
72
During tumor lysis syndrome, where will uric acid precipitate in the kidneys?
Lysis of tumor cells release intracelular ions, such as potasium, phosphorous, and uric acid into serum. Soluble at physiologic pH but precipitate in acidic environment of DISTAL TUBULES and COLLECTING DUCTS. Prevent symptoms via URINE ALKALINIZATION, HYD
73
3 conditions Aspergillus may cause
INVASIVE ASPERGILLOSIS - neutropenia predispose in immunosuppressed, lung most common presenting with hemoptysis and lung granuloma rx Amphotericin B. "FUNGUS BALLS" in old cavities and ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS (ABPA) - in patients with ast
74
What are pseudohyphae?
formd by elongated yeast Candida albicans - oval budding yeast with pseudohyphae
75
Cutaneous innervation of the musculocutaneous nerve?
Forms lateral cutaneous nerve of forearm, providing sensory innervation to the skin of the LATERAL FOREARM
76
What innervates the cutaneous skin of the medial forearm?
Ulnar nerve (medial cutaneous nerve of the forearm)
77
What innervates the thenar eminence?
Recurrent branch of the median nerve
78
What innervates the cutaneous skin of the posterior arm?
Posterior cutaneous nerve of the arm (radial nerve)
79
What could you add to the blood of a patient with hemophilia that would result in clotting?
THROMBIN!! (they can't convert prothrombin to thrombin which converts fibrinogen to fibrin)
80
2-day old neonate with bilious vomiting and laparotomy shows cecum fixed to the right upper abdominal quadrant. Explain embryologic process that failed.
Abnormal rotation and fixation of midgut during early fetal life results in intestinal malrotation. 2 main manifestations are INTESTINAL OBSTRUCTION (compression by adhesive bands) and MIDGUT VOLVULUS (intestinal ischemia due to twiisting aorund blood ves
81
What mechanism in the human body protects against C. diphtheriae?
Circulating IgG against the exotoxin B subunit. AB exotoxin has the B (think binding) subunit allows penetration of A (think Active) subunit into the cell, to INHIBIT RIBOSOME FUNCTION EF-2with Neural and cardiac toxiicity serious potental sequelae causin
82
Enzyme invovled in Essential fructosuria
Fructokinase - rare AR asymptomatic disorder, metabolism of fructose to fructose-6-phosphate, which is metabolised by HEXOKINASE in the liver is principal method of metabolism of dietary fructose.
83
Concern when initiating ACE inhibitors?
First-dose hypotension (mechanism: reduce venous return secondary to reduced ang2, activate Bezold-Jarisch reflex, vagally mediated hypotension and bradycardia) Predisposing risk factors include: Hyponatremia, hypovolemia secondary to diruetics, low basel
84
Apolipoprotein E-4 allele
AD, Late-onset, ApoE4 protein may be involved in the formation of senile plaques. AP on 21, Presenilin 1 on 14 and Presenilin 2 on 1 are associated with early onset AD
85
BPH may progress to:
reflux nephropathy, resulting hydronephrosis and renal interstitial atrophy and scarring ensue (parenchymal pressure atrophy). May cause permemanent damage and CRF! Treat immediately!!
86
High levels of dietary aflatoxin exposure (especially aflatoxin B1) cause this mutation
Classic G:C to T:A transversion in codon 249 of the p53 gene, greatly increasing the risk of developing hepatocellular carcinoma. When humidity and temp are favorable, strains of funghi Aspergillus flavus and Aspergillus parasiticus grow on corn, soybean
87
Most common cause of homocystinuria?
Defect in cystathionine beta synthetase, enzyme that converts homocystine to cystathionine. CYSTEINE becomes an essential amino acid in patients whty homocystinuria
88
Primary virulence factor, without which S. pneumoniae cannot cause disease
Polysaccharide capsule
89
4 common organ systems affected by HSP
Henoch-Schonleine purpura affects youn children and preceded by an URI, IgA- hypersensitivity (leukocytoclastic) vasculitis causing GIT (pain, bleeding), KIDNEYS (mesangial proliferation and crescent formation), SKIN (palpable purpura); JOINTS (migratory
90
2 most imporant congenital syndromes with QT prolongation
Romano-Ward syndrome (more common, no deafness) and Jervell and Lange-Nielsen syndrome (neurosensory deafness) - result from mutations in K+ channel protein that contributes to the delayed rectiifier current Ik of the cardiac AP. Both predispose to torsad
91
How does HBV facilitate HDV?
The HBsAg of HBV mus COAT the HDAg of HDV before it can infet hepatocytes and multiply. COATING OF VIRAL PARTICLES!
92
What are P bodies?
CYTOPLAMIC (only) P-bodies play an important role in mRNA translation regulation and mRNA degradation. Fundamental role in translation repression and mRNA decay, contain numerous proteins including RNA exonucleases, mRNA decapping enzymes, and mRNA qualit
93
Why can administering 100% oxygen to a patietn with severe COPD be dangerous?
Normally, respiratory center in medulla detects pH and is the main control over respiratory drive, it CANNOT SENSE paO2. Since they have profound hypercapneia, high concentrations of CO2 no longer stimulate the respiratory center. CHEMORECEPTORS in the C
94
Can a patient with turner syndrome get pregnant?
Yes, but likely requires oocyte donation - Ovarian failure, but normal uterus so endometrial response to estrogen and progesterone is normal
95
Function of Fructose 2,6-bisphosphate
Activates glycolysis by inducing PFK-1 and inhibits gluconeogenesis by inhibiting fructose 1,6-bisphosphatase. High fructosse 2,6-bisphosphate also decrease gluconeogenic conversion of alanine to glucose. Regulated by PFK-2 and F-2,6BP
96
How does viridans strep adhere to valves?
Produce dextrans using sucrose, facilitate adherence to FIBRIN and PLATELETS deposited at sites on ENDOTHELIAL TRAUMA, thus preexisiting endothelial damage must be present at cusps of valve leafelets.
97
Genetic mutation of hemochromatosis
Prevents expression of HFE protein (Chromosome 6) AR, on basolateral sufrace of intestinal cells where it normally binds to transferrin receptor and regulates (detects circulating iron levels) transferrin/iron complex endocytosis into cells. UNREGULATED
98
Mutation of FAS protien
prevent apoptosis of auto-reactive lymphyctes, thereby disposing the individual to autoimmune disorders such as SLE
99
Insulin activates
Anabloic hormone acts via tyrosine kinase to stimulate synthesis of glycogen, protein, fatty acids, and nucleic acids, Tyrosine kinase activates a PROTEIN PHOSPHATASE which directly modifies activity of enzymes in metabolic pathways regulated by insulin
