April 21 Flashcards
Failure of left and right hemispheres to separate and seen in Patau syndrome and fetal alcohol syndrome?
Holoprosencephaly–may be related to mutations in sonic hedgehog signaling pathway
What do MHC I molecules consist of?
Heavy chain and B2-microglobulin
–expressed on all nucleated cells
What is the function on enhancer sequence and where can it be found?
Stretch of DNA that alters gene expression y binding transcription factors
–may be located close to, far from, or even within (in an intron) the gene whose expression it regulates
Active SLE is characterized by…
Consumption of complement with reduced serum complement levels
–binding of autoantibodies to self-antigens leads to deposition of immune complexes in tissues and consumption of complement
What are the classic findings seen with neonatal abstinence syndrome and what is used to treat it?
Tremors–jittery movements and hypertonia
Irritability
Diarrhea
Poor feeding
Caused by opioid withdrawal–tx with methadone or morphine
What are the characteristics of schizotypal personality disorder?
Eccentric appearance, odd beliefs or magical thinking, interpersonal awkwardness
SchizoTypal= magical Thinking
Malignant cells with polygonal clear cells filled with accumulated lipids and carbohydrates?
Clear cell renal cell carcinoma —originates from PCT cells
Metastasizes to lung and bone
What are the high potency antipsychotics?
Trifluoperazine
Fluphenazine
Haloperidol
Try to Fly High–neurologic side effects–EPS
What are the low potency antipsychotics?
Chlorpromazine
Thioridazine
Cheating Thieves are low–anticholingeric, antihistamine, and a1-blockade effects
Silicosis is associated with increased susceptibility to _____ through what mechanism?
TB
–Macrophages respond to silica and release fibrogenic factors–leading to fibrosis–silica disrupts phagolysosomes and impairs macrophages –increased susceptibility to TB
Chlamydia trachomatis L1-L3 causes what and is characterized by…
lymphogranuloma venereum
Characterized by initial PAINLESS ulcer with later progression to painful inguinal lymphadenopathy (buboes) and ulceration
What is the cause of thoracic outlet syndrome?
Compression of lower trunk of brachial plexus and subclavian vessels –within scalene triangle–space bordered by anterior and middle scalene muscles and 1st rib
Syms worsen with overhead activity
- Upper extremity numbness
- Tingling
- Weakness
- Edema due to vascular compression
What is the MOA of amyl nitrate when given for cyanide poisoning?
Oxidizes Fe2+ —> Fe3+ –metHb which has high affinity for cyanide limiting toxic effects of cyanide
Thiosulfate and hydroxocolbalamin are also given which bind cyanide and eliminate in urine
What is the function of DNA polymerase I, found in prokaryotes only?
Excises RNA primer with 5’–>3’ exonuclease—removes RNA primary created by RNA primes and repair damaged DNA sequences
Same function as DNA polymerase III BUT also excesses RNA primer
What is the role of TATA and CAAT boxes?
Promoter–site where RNA polymerase II and multiple other transcription factors bind to DNA upstream from gene locus to initiate transcription
Atopic dermatitis (eczema) is associated with what?
Often associated with other atopic diseases
- Asthma
- Allergic rhinitis
- Food allergies
Increased serum IgE
B-oxidation of fatty acids is inhibited by what?
Malonyl-CoA
- -Acetyl-CoA is converted to Malonyl-CoA outside the mitochondria during De Novo fatty acid synthesis
- -Malonyl-CoA blocks Carnitine shuttle into mitochondrial matrix—blocking B-oxidation of fatty acids (blocks breakdown)
Spironolactone and epleronone inhibit aldosterone, which has what effect on the renal collecting tubule?
Blocks reabsorption of Na+
Decreases loss of K+ and H+
Normally aldosterone increases Na+ and H2O reabsorption within the collecting tubule and causes loss of K+ and H+ into the urine
High levels of ____ and ____ increase cholesterol solubility and decrease the risk of gallstone production.
Bile salts
Phosphatidylcholine
The scrotum drains into what lymph nodes?
Superficial inguinal lymph nodes
Histological picture of acute post streptococcal GN?
LM–glomeruli enlarged and hyper cellular
IF–“starry sky”–granular appearance (“lumpy-bumpy”) due to IgG, IgM and C3 deposition along GBM and mesangium
EM–subepithelial immune complex humps
What is the mechanism of action of Ipatropium?
Competitively blocks muscarinic receptors, preventing bronchoconstriction
NSAID use can cause what 2 renal diseases?
Acute interstitial nephritis
Renal papillary necrosis
Isolated atrial amyloidosis is due to what?
ANP-derived protein deposition
–common in normal aging
Bloody fluid obtain on thoracentesis. Pleural biopsy shows shows proliferation of epitheliod-type cells that are joined by desmosomes, contain abundant tonofilaments, and are stubbed with very long, slender microvilli. Dx?
Mesothelioma
What is the function of cord factor seen with TB?
Creates a serpentine cord appearance in virulent M. tuberculosis strains–inhibits macrophage maturation and induces release of TNF-a
Alanine can be converted to glucose, but first its amino acid is transferred to_____.
a-ketoglutarate
Alanine is responsible for transferring nitrogen to the liver for disposal –converted to glutamate through a-ketoglutarate where it turns into NH3 and enters the urea cycle
Multiple PAINFUL superficial vesicles or ulcerations with erythematous base on genitals in sexually active pt is suggestive of what?
HSV-2
Dx by PCR or tzanck stain
Pt with muscle wasting, cataracts, testicular atrophy, frontal balding, arrhythmia?
Myotonic dystrophy
–My tania, my testicles, my toupee, my ticker
AD–CTG trinucleotide repeat expansion in the DMPK gene–abnormal expression of myotonic protein kinase–> myotonia
What artery supplies most of the femoral head and neck and if damaged can cause osteonecrosis of the femoral head?
Medial femoral circumflex
Pt who underwent appendectomy has decreased suprapubic sensation, what nerve was most likely damaged?
iliohypogastric nerve–anterior branch
What white blood cell is increased with corticosteroid therapy?
Neutrophils –results from demmargination of neutrophils previously attached to the vessel wall
What are the functions of vWF?
Promotor of platelet adhesion at sites of vascular injury by binding platelet glycoproteins to sub endothelial collagen on injured blood vessels
Acts to protect carrier protein for circulating factor VIII
What is the most common cause of hypertrophic cardiomyopathy?
AD–mutation of the B-myosin heavy-chain
Low FSH = low _____ and Low LH = low _____.
Inhibin B–because its stimulated to release by FSH and causes negative feedback to stop FSH
testosterone
Chronic lymphedema, usually caused by lymph node dissection with breast cancer, put pt at increased risk of?
Angiosarcoma –rare blood vessel malignancy
Most common cause of death from friedreich ataxia, which is caused by trinucleotide repeat disorder–GAA on Ch 09 and leads to degeneration of multiple spinal cord tracts–> muscle weakness and loss of DTRs, vibratory sense, proprioception?
Hypertrophic cardiomyopathy
Staggering gait Frequent falling Nystagmus Dysarthria Pes cavus Hammer toes DM
Presents in childhood with kyphoscoliosis
Syndrome characterized by low plasma sodium and osmolarity, inappropriately concentrated urine, and clinically normal body fluid volume…
SIADH–seen with small cell carcinoma of the lung
What is a cell wall component and major virulence factor of H. influenzae?
PRP–polyribosylribitol phosphate
–part of type B—put in the vaccine which is conjugated to diphtheria toxoid
Risk factors for cervical cancer…
Infection with high risk HPV–16, 18, 31, 33
Hx of STD
Early onset sexual activity
Multiple or high risk partners Immunosuppression
History of vaginal or vulvar cancer
Low socioeconomic status
Tobacco use
Urge incontinence (overactive bladder) is tx with?
Anti-muscarinic drug–targeting M3 receptors
- -Oxybutynin
- -Solifenacin
- -Tolterodine
What childhood brain tumor shows cystic spaces filled with thick, brown-yellow fluid rich in cholesterol?
Craniopharyngioma —tumor of the anterior pituitary arise from remnants of Rathke’s pouch (embryonic precursor of anterior pituitary)
Intracranial calcified mass on imaging