Mixed Block Notes 3 Flashcards
Defect in Chediak-Higashi
Phagosome-Lysosome fusion –> Recurrent pyogenic infections with Staph and Strep
Features of Chediak-Higashi
Immunodef, Albinism, Neurologic (nystagmus, cranial neuropathies)
Phosphorylation of NRTI’s vs NNRTI’s
NRTI’s must be phosphorylated
Most important mechanism of lead poisoning
Affinity for sulfhydryl groups –> Inhibition of d-ALA dehydratase and ferrochetolase
Formation of d-ALA
Succinyl-CoA and Glycine via Pyridoxal Phosphate cofactor
Cause and manifestation of acute serum sickness
Type 3 (IC deposition) –> Fever, Pruritic skin rash, Arthralgias, Fibrinoid necrosis, Hypocomplementemia
Serum sickness can be caused by
Chimeric monoclonal Ab’s, Nonhuman Ig’s, Nonprotein drugs (eg penicillin, cefaclor, bactrim)
Osteolytic phase of Paget’s is due to excess
RANK signaling, NFKB activation
Pattern of bone in Osteoblast phase of Paget’s
Dense, hypovascular, mosaic pattern of lamellar bone with irregular, haphazardly oriented sections separated by prominent cement lines
What stimulates Inhibin B secretion
FSH stimulation of Sertoli cells
MOA of trihexyphenidyl
centrally-acting anti-muscarinic
Anti-cholinergics such as benztropine and trihexyphenidyl should be avoided in elderly patients, esp with
BPH, Angle-Closure Glaucoma
S-100 protein function
Homodimeric calcium-binding proteins, important for protein p-lation, cell growth, and differentiation
S-100 marks what cells
Neural Crest (melanocytes, Schwann), Langerhans and other dendritic
DLCO depends on
Thickness and total SA of alveolar capillary membrane, Hematocrit, Total volume of pulmonary capillary blood
DLCO in emphysema vs chronic bronchitis
Reduced in Emphysema, Normal in CB
Mechanism of Bohr effect
CO2 –> H+ and HCO3+ –> H+ binds histidine side chains of Hb –> Stabilize deoxygenated form of Hb
What happens to H+ and HCO3 in RBC from CO2
H+ binds Hb; HCO3 exchanged for Cl (Cl enters)
Which step of Glycolysis utilizes NAD+
G3P –> 1,3-BPG
When is FADH2 produced
During conversion of succinate to fumarate
Synthesis of Carnitine
Lysine + Methionine via Vit C cofactor
Citrate is formed from
Condensation of Acetyl CoA w/ OAA
Heart Failure definition
(1) Cannot pump enough blood to meet demand; or (2) Can onliy do so from elevated ventricular filling pressure
Diarrhea in pellagra results from
Columnar epithelium atrophy
NAD functions as a coenzyme for
Dehydrogenases involved in metabolism of fats, carbs, and amino acids
Niacin can be synthesized endogenously from
Tryptophan
Populations that primarily subsist on __ are prone to developing pellagra
Corn (niacin in corn is bound and unabsorbable)
Pellagra is less commonly seen in what patient populations
Carcinoid, Prolonged INH, Hartnup (more commonly in alcoholics and chronic disease)
Arginine is a precursor of
NO, Urea, Ornithine, Agmatine, Creatine
Orotic acid is a precursor of
Pyrimidine
Ab-dependent cellular cytotoxicity is defense against
Virus, Parasite
Function of MPO
Hypochlorite from H2O2 and Chlorine
Testicular feminization syndrome =
Complete Androgen Insensitivity = Absent Wolffian and Mullerian structures
Pulmonary hypertension is usually found in patients with
Scleroderma
H1 receptors are found in
Vascular endothelium, Bronchial smooth muscle
5 important classes of meds with Anti-muscarinic effects
Atropine, TCA’s, H1 blockers, Neuroleptics, Anti-Parkinson - NATHA
MOA of Ribavirin
Nucleoside antimetabolite - (1) Lethal hypermutation, (2) Inhibit RNA polymerase and IMP DH (depleting GTP), (3) Defective 5’-cap formation on viral mRNA, (4) Modulating a more effective immune response
Bone turnover is regulated by ratio of
RANKL to OPG - incr when RANK-L high and OPG low
How does PTH activated Osteoclasts
Stimulates Osteoblasts to upregulate RANKL and secrete M-CSF –> Osteoclast maturation
Function of Osteoprotegrin
Decoy RANK-L receptor
Arachnodactyly, Scoliosis, and Aortic Root Dilatation are signs of
Marfan
Macroorchidism, Large Jaw, and Intellectual disability are signs of
Fragile X
Top 3 causes of meningitis in neonates
GBS, E coli, Listeria
Courses between Biceps brachii and Coracobrachialis
Musculocutaneous
Courses between Flexor Carpi Ulnaris and Flexor Digitorum Profundus in forearm
Ulnar
Courses between Flexor Digitorum Profundus and Flexor Digitorum Superficialis
Media N
Substrate for PRPP synthetase
Ribose-5-Phosphate
Gout occurs with increased frequency in patients with activating mutations of
PRPP Synthetase
First line for Acute Gouty Arthritis
NSAIDs (Colchicine second)
How does pregnancy affect gallstones?
Estrogen-induced cholesterol hypersecretion (HMG CoA Reductase); Progesterone reduces bile acid secretion and slows gallbladder emptying
Fluid-filled cavitiy in liver + Fever, Chills, RUAbdominal Pain
Most likely bacterial abscess in developed nation
Pyogenic bacteria most commonly gain access to liver via
Biliary tract, Portal vein pyema, Hepatic artery
How does RBC carry CO2
15% as carbamate on Hb, Remained as bicarb ion w/in RBC
Diuretic often used in management of Cerebral edema and Incr ICP
Mannitol
Overaggressive treatment with osmotic diuretic therapy
Excessive volume depletion and eventual hypernatremia
Osmotic diuretics should be used cautiously in what patients
CHF, Pre-existing pulmonary edema
Spironolactone side effects
Hyperkalemia, Gynceomastia, Decr libido, Erectile dysfunction
The risk of statin myopathy is increased when
Fibrates and/or Niacin also used
Drugs that can cause myopathy
SGFC PHIN - Statins, GC’s, Fibrates, Colchicine, Penicillamine, Hydroxychloroquine, IFNa, Niacin
MOA of Fenodolpam
Benazepine derivative of DA –> Selective DA-1 agonist with no effect on alpha or beta receptors
Stimulation of DA receptors in kidneys
Improves RBF and Na and Water excretion
Fenoldopam is indicated for
Short term management of severe HTN
Use and risk of Nitroprusside
Most effective agent for most cases of HTN emergency –> Cyanide toxicity
Vimentin is a marker for
Mesenchyme
Chromogranin A
Neuroendocrine tumors
Imperforate anus is most commonly associated with
GU malformation - VACTERL (vertebral, anal atresia, cardiac anomalies, TE fistula, esophageal atresia, renal anomalies, limb anomalies)
Fibrinous pericarditis is most commonly caused by
MI, RF, Uremia; Also viral
Pericardial knock
Brief, high frequency, precordial sound heard shortly after S2 in constrictive (chronic) pericarditis
Heme in the liver is synthesized for
CYP450 system
Acute Intermittent Porphyria can be precipitated by
Phenobarbital, Griseofulvin, Phenytoin, Low calorie diet, Alcohol –> All decr hepatic heme –> Incr ALA synthase activity
Heme synthesis enzymes inhibited by lead
ALA dehydratase, Ferrochetolase
Influenza vaccine induces
Neutralizing antibodies against Hemagglutinin
Why don’t killed vaccines stimulate CD8 response
They don’t enter host cell for MHC Class 1 presentation
Sensory nerve to parietal pleura
Phrenic to Diaphragmatic and Mediastinal; Intercostal to remainder
Superficial Inguinal Nodes drain
Nearly all cutaneous lymph from umbilicus to feet, including external genitalia and anus
Lymph from Glans penis and cutaneous portion of posterior calf drain into
Deep inguinal lymph directly (bypassing superficial)
Effect of cyanide poisoining
Inhibits cytochrome C oxidase - SaO2 of venous blood increases due to failure of oxygen unloading
Crescents of RPGN are composed of
Proliferated glomerular parietal cells, Monocytes, Macrophages, Fibrin
Inactivated HFE increases iron by
(1) Incr DMT1 on enterocytes; (2) Decr hepcidin –> Incr ferroportin expression
Atypical antipsychotics most and least likely to cause EPS
Clozapine least likely, Risperidone most likely
Top 3 risk factors for Coronary Heart Disease
Noncoronary Athersclerotic Disease, Diabetes Mellitus, CKD
Pineal Tumors most commonly cause
Parinauds, Precocious puberty, Obstructive hydrocephalus
Short acting insulins
Lispro, Aspart, Glulisine
When to use regular insulin
DKA
What accounts for delayed onset of regular insulin
Dimer and hexamer formation (short acting are monomers)
NPH insulin works by
Crystalline suspension with protamine and zinc –> Delays absorption
Detemir insulin works by
FA bound to lysine –> Binds albumin and slowly dissociates
MAOi’s
MAO Takes Pride In Shanghai = Tranylcypromine, Phenelzine, Isocarboxazid, Selegline (B selective)
SSRI’s
Flashbacks Paralyze Senior Citizens = Fluoxetine, Paroxetine, Sertraline, Citalopram
SNRI’s
Venlafaxine, Duloxetine
How quickly after ischemia does loss of contractility occur in cardiomyocytes?
60 seconds
At what timepoint is myocardial ischemia irreversible
30 minutes
Ligands for Receptor Tyrosine Kinase vs JAK/STAT
Growth Factors bind RTKs; JAK/STAT bound by Cytokines, Growth Hormone, Prolactin, IL-2, EPO
Microscopy of Membranous Glomerulopathy
LM - Mesangial proliferation; IF - Ig and C3; EM - Spike and Dome
T-ALL is most likely to present
Anterior Mediastinal mass that compresses great vessels and esophagus
EKG progression of Acute Transmural Infarct
Peaked T waves –> STE –> Q waves
Imaging in Gallstone Ileus shows
Intestinal gas (obstruction), Air in biliary tree
Boerhaave Syndrome
Transmural tear (vs Mallory Weiss which is mucosal)
Cricopharyngeal motor dysfunction occurs due to
Diminished relaxatin of pharyngeal muscles during swallowing
Renal consequences of Ethylene Glycol ingestion
Oxalate crystals, Tubular epithelial damage (ballooning and vacuolar degeneration mostly in PCT)
