uWorld 60 Flashcards
what happens in proliferative phase (days 1-14_ of menstrual cycle
starts with first day of menses and ends with ovulation
ESTROGEN stimulates proliferation of stratum FUNCTIONALE
normal proliferative endometrium consists of NONBRANCHING, NONBUDDING, uniform glands evenly distributed throughout a uniform stroma
mid-proliferative phase- glands are TUBULAR, NARROW, and lined with pseudo stratified, elongated, mitotically active epithelial cells
stratum functional contains compact, non edematous stroma
uterine glands have increased length and girth but still remain relatively STRAIGHT
endometrial biopsy AT OVULATION shows what
late proliferative endometrium with COILED GLANDS and occasional cytoplasmic vacuoles in the granular epithelium
what is seen in the secretory phase (days 15-28) of the menstrual cycle
PROGESTERONE secreted by CORPUS LUTEUM in the ovary promotes the development of secretory endometrium
the glands increase in size and becomes MORE COILED, and the cells lining the lgnads acquire large cytoplasmic VACUOLES
glycogen-rich mucus is released into the glandular lumens
stroma becomes increasingly edematous, and the prominent sSPIRAL ARTERIES extend to the ENDOMETRIAL SURFACE
beta-thalassemia can be due to the inherited beta global gene mutation in what
KOZAK SEQUENCE, a consensus sequence that helps start translation in eukaryotes
EUKAYOITC TRANSLATION INITIATION requires the assembly of ribosomal sobuines (60S and 40S), mRNA, initiation factors, initiator tRNA charged with methionine, and guanosine-5’-triphosphate (GTP)
the small ribosomal subunit (40S) initially binds to the 5’ cap of mRNA and scans for the METHIONINE START CODON (AUG)
when this star codon is positioned near the beginning of an mRNA molecule and is surrounded by the Kozak consensus sequence, it serves as the initiator of translation
the KOZAK CONSENSUS SEQUENCE is analogous to the Shine-Dalgarno sequence in E. coli
co-translational protein targeting is mediated by what
N-terminal amino acid sequence of an elongating polypeptide
signal sequence is recognized by a signal recognition particle, which helps transport the protein to the rough endoplasmic reticulum
peptide bond formation is catalyzed by what
peptides transferase, an RNA enzyme (“ribozyme”) that resides in the large ribosomal subunit
a defect in rRNA coding for ribosomes would be required to interfere with this process
ribosomal translocation during polypeptide elongation requires what
elongation factor 2 and requires GTP hydrolysis
this advances the peptides tRNA from the A site to the P site (translocation)
what is the mutation in sickle cell
A to T mutation in the beta global gene that results in glutamate being substituted with valine at position 6
what causes the damage the the RBC membrane in beta thalassemia
decreased beta global chain synthesis results in UNPAIRED ALPHA CHAINS that precipitate within red cells and cause membrane damage, leading to ineffective erythropoiesis and extravascular hemolysis
what does Aldolase B catalyze
fructose-1-phosphate to DHAP and glyceraldehyde
glyceraldehyde is then converted to glyceraldehyde-3-phosphate (glycolysis) by TRIOKINASE
what is seen in aldolase B
hereditary fructose intolerance starts after breastfeeding is DONE and fruits started
VOMITING and HYPOGLYCEMIA about 20-30 minutes after fructose ingestion
IRRITABILITY, JAUNDICE, HEPATOMEGALY, FAILURE to THRIVE
undiagnosed eventually develops LIVER and RENAL FAILURE
TX: no more fructose
glactose-1-phosphate uridyl transferase (classic galactosemia)
AR
vomiting, feeding intolerance, neonatal jaundice, hepatomegaly, death if untreated
starts soon after breastfeeding is INITIATED
tryptophan is the precursor for what
niacin, serotonin, melatonin
what is the MOA of rifaximin
non absorbable antibiotic that alters GI flora to DECREASE INTESTINAL PRODUCTION and ABSORPTION of AMMONIA
someimtes used to treat traveler’s diarrhea, as it inhibits bacterial RNA synthesizes through binding with DNA-depended RNA polymerase
generally used in addition to lactulose (catabolized in the intestine bacterial flora to shoot chain fatty acids, lowering the colonic pH and increasing conversion of ammonia to ammonium)
what do phosphate binders (calcium acetate) do
lower serum phosphate in patients with end-stage renal disease
what does sodium polystyrene resin do
exchanges intraluminal sodium for potassium ions and can lower serum potassium in patients with hyperkalemia
what are the recommendations for prevention of CENTRAL VENOUS CATHETERS (CVC)
HAND HYGIENE with an ALCOHOL SANITIZER or SOAP and WATER
maximal BERIEF PRECAUTIONS during insertion (surgical mast, sterile gloves, long-sleeved surgical gown, and a large sterile sheet drape)
preparation of the insertion site with CHLORHEXIDINE antiseptic
use of SUBCLAVIAN or INTERNAL JUGULAR insertion sites (femoral vein has high risk of infection)
prompt removal of the catheter when it is no longer needed
what are the GAS antigens that there are antibodies for in acute rheumatic fever
M PROTEIN
N-ACETYL-BETA-D-GLUCOSAMINE
whats a cystic hygroma look like on physical
LOBULATED, COMPRESSIBLE, usually
TRANSILLUMINATES
what is seen histologically in deQuervaine thyroiditis
aka subacute GRANULOMATOUS thyroiditis
inflammatory infiltrate with macrophages and GIANT CELLS
increase ESR and CRP
decreased radio nucleotide uptake
transient hyperthyroid symtoms
PAINFUL thyroid enlargement
onset following VIRAL ILLNESS
when do you see HURTHLE CELLS (eosinophilic epithelial cells)
HASHIMOTO THYROIDITIS
anti TPO (microsomal) antibody
painless
GERMINAL CENTERS
what is RIEDEL thyroiditis
characterized by extensive FIBROSIS of the thyroid that EXTENDS into surrounding tissues
thyroid gland is hard and non-tender
what are possible causes of monocular scotoma
macular degeneration or optic neuritis
partial lesion in the retina, optic disc, optic nerve
in a patient with fucked up patella what might allow them to have partially spared knee extension
if lateral and medial RETINACULUM are intact