uWorld 1 Flashcards
what are club (aka clara) cells and what are their role
nonciliated, secretory constituents of the terminal respiratory epithelium
secrete club cell secretory protein and surfactant components
help detoxify inhaled substances via CYP450 mechanism
what cells are responsible for the findings in centriacinar emphysema
neutrophils and macrophages release PROTEASES (elastase, cathespins, MMPs) that degrade the eco and also generate free oxygen radicals that impair the function of protease inhibitors (A1AT)
weight loss, mucosal pallor, hepatomegaly, and massive splenomegaly
gain-of-function mutation of non-receptor tyrosine kinase protein in hematopoietic cells, leading to persistent activation of signal transducers and activators of transcription (STAT) proteins
JAK 2 mutation
primary myelofibrosis
teardrop cells (dacrocytes) on peripheral smear
what is ruxolitinib
JAK2 inhibitor
approved for treatment of primary myelofibrosis
hydrocele results from what
incomplete obliteration of the PROCESSUS VAGINALIS (a projection of the peritoneal cavity that accompanies the descendant testis into the scrotum and ultimately toms the TUNICA VAGINALIS of the testis)
what causes a bifid scrotum
malunion of labioscrotal folds (forms labia majora in females)
what is the most common cause of CF
3-bp deletion that removes phenylalanine at deltaF508
impaired post translational modification in the endoplasmic reticulum (goes to proteasome and no CFTR on the cell surface at all)
what kind of CF is seen in Ashkenazi jews
mutations causing premature termination of the transmembrane protein (nonsense, frameshift) also lead to a complete absence of membrane-bound CFTR
mild CF disease is usually do to what
mutations impairing chloride iron conduction through CFTR or those causing decreased production of functionally normal CFTR (reduced mRNA or protein stability)
what organism is gamma-hemolytic (no hemolysis) catalase-negative, can grow in presence of bile, but cannot grow in 6.5 NaCl
S. bovis
enterococci are the same except they can grow in 6.5NaCl
what organisms are PYR (pyrrolidonyl arylamidase) positive
Strep progenies
enterococci
what biochemical processes occur exclusively in the mitochondria
beta-oxidation of fatty acids ketogenesis citric acid cycle parts of urea cycle (carbamoyl phosphate synthetase 1 and ornithine transcarbamoylase) pyruvate carboxylation
where does the pentose phosphate shunt occur
cytoplasm
transketolase is an enzyme of this pathway (B1 is a cofactor)
what does pyruvate carboxylase do and where is it found in the cell
catalyzes the initial step in gluconeogeneissi by converting pyruvate to oxaloacetate (B7 is cofactor)
mitochondria
what does ornithine transcarbomoylase do and where is it found in the cell
catalyzes the second step of the urea cycle where ornithine and carbamoyl phosphate are combined to form citrulline
mitochondria
deficiency leads to hyperammonemia and mental retardation
what does succinate dehydrogenase do and where is it found in the cell
enzyme of TCA cycle that converts succinate fumarate
FAD+ to FAD2 happens here
inner mitochondrial membrane
what does HMG CoA Lyase do and where is it found in the cell
mitochondrial enzyme that is responsible for ketogenesis from HMG CoA
what is reaction formation
defense mechanism in which an individual TRANSFORMS UNACCEPTABLE FEELINGS or impulses into their EXTREME OPPOSITES
immature defense mechanism