uWorld 32 Flashcards
what is seen in a newborn with midgut malrotation
cecum wil rest in the right upper quadrant instead of the right lower quadrant
LADD’S (FIBROUS) BANDS connect the retroperitoneum to in the RLQ to the right colon/cecum by PASSING OVER the SECOND PART of the DUODENUM, causing INTESTINAL OBSTRUCTION in the process
obstruction presents as BILIOUS VOMITING during the FIRST DAYS of life
mesentery is vulnerable to tWISTING around the SUPERIOR MESENTERIC ARTERY- midgut VOLVULUS which comprises intestinal profusion and may lead to life-threatening bowel necrosis
what is seen if a lower cutoff point is used (in terms of sensitivity and stuff)
increase in number of overall positive results
sensitivity of the test increases
true positive values increase but false positive increase more
positive predictive value decreases
false negatives decrease
anovulation is a common cause of infertility how can this be treated
menotropin (human menopausal gonadotropin) is a treatment option that acts like FSH and trigger the formation of a dominant ovarian follicle
ovulation is then induced by administration of human chorionic gonadotropin which mimics the LH surge
when during menstruation are peak progesterone levels
mid luteal phase
after ovulation when the corpus luteum is formed
nitric oxide is formed from what
ARGININE, NADPH, and O2 by eNOS (endothelial nitric oxide synthase)
NO activates guanylyl cyclase → cGMP → less cytosolic coliseum and RELAXATION of vascular smooth muscle cells
arginine is used to make what
nitric oxide
urea (w/ help of aspartate)
creatine (w/ help of glycine and SAM)
aspartate is used to make what
urea (w/ help of arginine)
pyrimidines (w/ help fo glutamine
purines (w/ help of glycine and glutmaine)
glycine is used to make waht
heme (w/ help of succinyl CoA)
creatine (w. help of arginine and SAM)
purines (w/ help of glutamine and aspartate)
glutamine is used to make what
pyridines and purines
what is glutamate used to make
GABA
glutathione
what all is derived form tyrosine (which comes from phenylalanine itself)
dopamine epinephrine norepinephrine thyroxine melanin
what is asymmetrical dimethyarignine
an endogenous analog of arginine that work as a competitive inhibitor of eNOS
what is nor present in all tRNAs
variable loop (lies between the T and anticodon loops)
what is the T loop of tRnA
has the T(psi)C sequence- necessary for BINDING of tRNA to RIBOSOMES
(ribothymidine and pseudouridine, and cytidine presence tells you this is around)
what are ApoE3 and ApoE4 responsible for
found own CHYLOMICRONS and VLDL
binding hepatic apolipoprotein receptors for their removal
what is ApoA1 required for
esterification of free cholesterol in HDL particles by lecithin-cholesterol acyltransferase (LCAT)
ApoA1 and LCAT deficiencies result in low HDL levels and increased circulating free cholesterol levels
what is familial chylomicronemia syndrome and what causes it
AR disorder of defective LIPOPROTEIN LIPASE or ApoC3 (which activates LPL)
increased synthesis and decreased clearance of chylomicron particles (and VLDL)
why is DNA polymerase I unique
only prokaryotic polymerase that also has 5’ to 3’ EXONUCLEASE ACTIVITY
functions to REMOVE the RNA PRIMER reacted by RNA primase and REPAIR DAMAGED DNA sequences
what is the major early biochemical consequence of total myocardial ischemia and when does it happen
cessation of aerobic glycolysis and initiation of anaerobic glycolysis
transition occurs within seconds
although TOTAL ATP levels remain normal during first few minutes of ischemia, ATP is rapidly depleted form areas of cell with high demand
the DEPLETION of ATP in CRITICAL CELLULAR areas and the ACCUMULATION of TOXINS results in LOSS of CONTRACTILITY within about 60 seconds of total myocardial ischemia
when does ischemia become irreversible
after about 30 minutes of TOTAL ISCHEMIA
what are benign lung tumors
HAMARTOMAS
“coin lesions” found incidentally on chest x-ray
mature hyaline cartilage mixed with connective tissue, smooth muscle, and fat
what is seen in adenocarcinoma in site (aka bronchioloalveolar carcinoma)
consists of WELL-DIFFERENTIATED, dysplastic COLUMNAR CELLS (with or without MUCIN) that line the INTACT alveolar septa without vascular or stromal invasion
tendency to undergo erogenous spread and can progress to invasive disease if not resected
what causes edwards syndrome (trisomy 18)
MEIOTIC NONDISJUCNTION
error in oocyte division occurs prior to ovulation and fertilization and increases with maternal age over 35
what is seen in cri-du-chat syndrome
microdeleiton of 5p
cat-like cry as well as hypotonia, failure to thrive, developmental delay
microcephaly
low-set ears
hypertelorism
broad nasal bridge
anti-Rh immune globulin consists of what
IgG anti-D antibodies that opsonize Rh+ fetal erythrocytes, promoting clearance by material reticuloendothelial macrophages and preventing maternal Rh sensitization
giben at 28 weeks gestation and immediate postpartum period
what is ANASTROZOLE (and letrozol, exemestane)
ATOMATASE INHIBITOR
reduce synthesis of estrogen from androgens, surpassing estrogen levels in post menopausal women and SLOWING PROGRESSION of ER-POSITIVE TUMORS
less effective in premenopausal women become ovarian aromatase is unregulated substantially in response to gonadotropins
what diuretics work as the thick descending loop of henle
osmotic (also work at proximal convoluted tubule)
what is seen in Jugular Foramen (Vernet) Syndrome
CN IX, X, XI dysfunction
loss of ease from posterior 1/3 of tongue (CN IX)
loss of gag reflex (CN IX, X)
dysphagia (CN IX, X)
dysphonia/hoarseness (CN X)
soft palate drop with deviation of the uvula toward the normal side (CN X)
sternocleidomastoid and trapeius muscle paresis (CN XI)
what causes the shift of pain in appendicitis to shift from the umbilicus to McBurneys point (2/3 form umbilicus to ASIS)
the appendix becomes more inflamed and ti irritates the PARIETAL PERITONEUM and abdominal wall and causes a MORE SEVERE SOMATIC PAIN
an inflamed appendix lying against what would cause RLQ pain with INTERNAL ROTATION of the RIGHT HIP
RIGHT OBTURATOR INTERNUS
an inflamed appendix lying against what would cause RLQ pain with HIP EXTENSION
PSOAS
how does botulism usually present
3D’s:
DIPLOPIA, DYSPHAGIA, DYSPHONIA usually 12-36 hours after consumption
descending paralysis
HEAT-LABILE disease that can be prevented by thoroughly heating food prior to consumption
what does hemicholinium do
blocks choline uptake by the presynaptic neuron
prevents ACh synthesis through depletion of intracellular choline
what does bromoacetylcholine do
inhibits acetyltransferase
blocking the synthesis of ACh from acetate and choline
what id VESAMICOL
non competitively blocks the vesicular ACH transporter, preventing ACh from ENTERING SECRETORY VESICLE
patient with microcytic anemia and low ferritin (suggesting iron deficiency anemia) and history of heavy menstrual periods and nosebleeds as a kid
whats she got
von Willebrand factor deficiency (bleeding from skin and mucosal sites)
iron deficiency from occult blood loss due to above
what is the role of vWF
promoter fo platelet adhesion at sites of vascular injury by binding platelet glycoproteins (Gp1b) to sub endothelial collagen on injured blood vessel walls
protective carrier for factor VIII
what is PARANEOPLASTIC CEREBELLAR DEGENERATION (subacute cerebellar degeneration)
paraneoplastic syndrome associated with SMALL CELL LUNG, breast, ovarian, and uterine malignancies
progressively worsening DIZZINESS, LIMB, and TRUNCAL ATAXIA, DYSARTHRIA, and VISUAL DISTURBANCES (diplopia, oscillopsia)
immune reaction against tumor cells that CROSS-REACTS with PURKINJE neuron ANTIGENS, leading to acute-onset rapid degeneration of the cerebellum
Anti-Yo, anti P/Q and anti-Hu antibodies are seen in what paraneoplastic syndrome
PARANEOPLASTIC CEREBELLAR DEGENERATION (subacute cerebellar degeneration)
(seen in SMALL CELL LUNG, breast, ovarian, and uterine malignancies)
Wegeners (granulomatosis with polyangitis) does what in the kidney
rapidly progressive (crescent) glomerulonephritis (RPGN) type 3 (pouci immune)
serrates anterior is innervated by what, what is its action
LONG THORACIC nerve (C5-C7_
stabilize and ROTATE the SCAPULA UPWARD
paralysis of serratus anterior (knife wound to side of chest, radical mastectomy) does what
winged scapula
weakness abducting the arm able horizontal due to impaired rotation of the scapula
what are the side effects of amphotericin B
renal toxicity: severe hypokalemia and hypomagnesemia (likely reflecting increased distal tubular membrane permeability) can decrease EPO production vasoconstriction and ↓ GFR acute tubular necrosis renal tubular acidosis
what is a side effect of daptomycin
rhabdomyolysis (increased creatine phosphokinase)
TSH monitoring is recommend for people on what drugs
amiodorone
lithium
what do aprepitant and posaprepitant do
neurokinin 1 (NK1) receptor antagonists
inhibit substance P and help prevent both acute vomiting and delayed emesis
what do Golgi Tendon Organs do
sensory receptors located at the junction of the muscle and tendon that are innervated by GROUP IB sensory axons
connected in series with contrasting extrafusal skeletal muscle fibers
when a muscle actively contracts against resistance, the increase in tension is transmitted through the tendon activating the GTOs in the process
not sensitive to muscle length change (happens primarily at the fibers not the tendon)
muscle spindles (intrafusal muscle fibers) are innervated by what
innervated by GROUP IA and GROUP II sensory axons and are sensitive to changes in muscle length
mediate the STRETCH REFLEX (MYOTATIC reflex) which is commonly tested (deep tendon reflexes) during the neurologic examination
when the muscle is stretched there is a monosynaptic reflex activation of the alpha motor neuron (of the same muscle), causing contraction that resists the stretch
connected in parallel with extrafuscal fibers
what do pacinian corpuscles do
RAPIDLY adapting mechanoreceptors
subcutaneous tissue of the skin as well as the mesentery, peritoneum, and joint capsules
mediate touch, proprioception and vibratory sensation
inverted by MYELINATED A-beta fibers
what are Ruffini’s end organs
SLOWLY adapting mechanoreceptor that exist in the skin, subcutaneous tissue and joint capsule
mediate touch, proprioception and vibratory sensation
inverted by MYELINATED A-beta fibers
what are A-delta fibers
thin, myelinated nerve fibers whose FREE NERVE ENDINGS detect TEMP and NOCICEPTIVE stimuli
acute (sharp) pain and constitute afferent portion of the REFELX ARC that mediates WITHDRAWAL from NOXIOUS STIMULI
colitis-associated carcinoma is more likely to have what features (compared to sporadic colorectal carcinoma)
- affect YOUNGER patines
- progress from FLAT and NON-POLYPOID DYSPLASIA
- histologically appear MUCINOUS and/or have SIGNET RING morphology
- develop EARLY p53 mutations and LATE APC gene mutations, opposite that of sporadic disease
- be distributed within the PROXIMAL COLON (esp in Crohns or primary sclerosing cholangitis)
- be MULTIFOCAL in nature
collitis-asociated carcinomas are more likely to arise from non-polypoid dysplastic lesions, be multifocal in nature, develop early p53 mutations and late APC gene mutations, and be of a higher histological grade
know that
what is the most effective strategy at preventing neonatal tetanus
vaccination of pregnant woman (and those of childbearing age)- this provides TRANSPLACENTAL IgG to the fetus
hygienic delivery and cord care
clump of soli on umbilical cord
TETANUS
how its tetanus treated
antibiotics to kill C tetani and administration of tetanus immune globulin to neutralize unbound toxin
what is pure red cell aplasia (PRCA)
rare form of marrow failure characterized by severe hypoplasia of marrow ERYTHROID elements in the setting of normal granulopoiesis and thrombopoisesis
what causes pure red cell aplasia (PRCA)
inhibition of erythropoietic precursors and progenitors by IgG autoantibodies or cytotoxic T lymphocytes
associated with immune system diastase such as THYMOMAS and LYMPHOCYTIC LEUKEMIAS
PARVOVIRUS B19 (can detect anti-B19 IgM antibodies)- virus preferentially attacks and destroys proerythroblasts
what does IkappaB do
bind NF-kappaB and keeps it in a latent, inactive state
activation of IkappaB KINASE results in UBIQUITINATION and subsequent destruction of IkappaB with the release of free NK-kappaB
once free, NK-kappaB enters the nucleus and promotes the synthesis of a number of INFlAMMATORY PROTEINS such as cytokines, acute phase reactants, cell adhesion molecules, and leukocyte related growth factors
what is TNF-alphas role in response to infection
increase neutrophil chemotaxis and stimulating macrophage phagocytosis
unregulated by NF-kappaB
how does HBV increase risk for hepatocellular carcinoma
integrates into host DNA
(this allows for transcription of viral oncogenic proteins like HBc PROTEIN which disrupts cell-cycle control by activating multiple gtowth-proming genes an inactivating p53 TUMOR SUPPRESSOR PROTEIN)
