uWorld 7 Flashcards
what is a distinct histopathologic manifestation of chronic hepatitis B
accumulation of HEPATITIS B SURFACE ANTIGEN within infected cytoplasm
appears as FINELY GRANULAR, HOMOGENOUS, DULL EOSINOPHILIC INCLUSION that fill the cytoplasm (ground glass hepatocytes)
hepatocyte necrosis (ballooning degeneration), apoptosis, steatosis, portal inflammation with mononuclear inclusions (lymphocytes, macrophages)
what is seen in a liver infected with chronic hep C
lymphoid aggregates within portal tracts and focal areas of macrovesicular steatosis
progesterone only pill and levonorgestrel intrauterine device prevent pregnancy how
thickening cervical mucus preventing sperm from accessing the uterus
how do copper IUDs prevent pregnancy
copper ions elicit an inflammatory reaction in the uterus that is toxic to sperm and prevents fertilization
anti-mitochondrial antibodies are seen in whom
primary biliary cirrhosis
anti-centromere antibodies are found in whom
CREST syndrome
what part of the sarcomere only has thick (myosin) filaments
H-band (portion of A band that straddles the M line- which looks like two white lines on EM)
what part of the sarcomere is always the same length
what parts decrease in length during contraction
A band- corresponds to the thick filaments but includes where they overlap the thin (actin) filaments
H band and I band decrease in length during contraction
what part of the sarcomere contains only thin filaments and what makes up the thin filaments
I band which contains the Z line (typically distinctly darker than the reminder of the sarcomere)
Z-line is anchor for thin filaments (actin, tropomyosin, troponin)
what are the promoter sequences of eukaryotes
TATA (Hogness) box- 25 bp upstream for gene
CAAT box- 70 to 80 bp upstream of the gene
Ehlers danlos is due to a what kind of problem
college synthesis- DEFICICENY in PROCOLLAGEN PEPTIDASE- enzyme that cleaves terminal N and C pro peptides from procallagen in the extacellulat space
collagen DOES NOT PROERPLY CROSSLINK
how do corticosteroids (bethamethasone, dexamethasone) increase surfactant production
accelerating maturation of type II pneumocytes
at risk pregnancies for preterm birth, antenatal administration of magnesium sulfate has been shown to decrease risk for what
cerebral palsy
vesicles on the lips and hard palate with fever and lymphadenopathy is characteristic of what
gingivostomatitis (gums and hard palate are KEY)
(recurrent lesions are not as severe due to existing cellular and humoral immunity)
KEEP IN MIND: hand foot mouth is SOFT PALATE, buccal mucosa, tongue
what is seen on Tzanc smear of HSV
multinucleate giant cells and intranuclear inclusion bodies
dihydrorhodamine flow pyrometry testing revealing absence of the teen fluorescence that is characteristic of normal neutrophils is suggestive of what
Chronic Granulomatous Disease (NADPH oxidase deficiency)
X-linked mutation
how do mu opioid receptors work
G protein-linked that activate secondary messenger pathways
POTASSIUM CONDUCTANCE is a major pathway- hyper polarizing postsynaptic neurons and termination of pain transmission
also can inhibit adenylate cyclase, calcium conductance, and transmitter release
what is believed to be the primary causes of lacunar infarcts
lipohyalinosis and microatheromas (result form atherosclerotic accumulation of lipid-laden macrophages within the intimal later of penetration artery near its origin off the parent vessel)
these changes predispose to small-vessel occlusion and infra of the CNS with liquefactive necrosis
what is a common side effect of thaiazolidinedione therapy (pioglitazone and rosiglitazone)
fluid retention with resultant weight gain and edema
can exacerbate underlying heart failure
arterial puncture above the inguinal ligament (when trying to access the common femoral artery) increases risk for what
retroperitoneal hemorrhage (which cannot be controlled by manual compression and can lead to significant hemorrhage)
bleeding into the pelvic cavity occurs due to what
pelvic trauma in men
trauma or gynecologic hemorrhage
what is the right paracolic gutter and when does bleeding enter this space
space b/w ascending colon and abdominal was
pathology involving the GI organs (duodenum, gallbladder) causes fluid (bile, pus, blood) to accumulate here
hemorrhage into thigh muscles would present how
significant pain and edema and possibly compartment syndrome
what is responsible for the variation of bone mass in individuals
genetic factors
pyrrolidonyl arylamidase (PYR) is positive for what organism
strep pyogenese
what compensatory mechanism stops peripheral edema from occurring in COPD patients
increased tissue lymphatic drainage
right HF increased central venous pressure, leading to rise in capillary hydrostatic pressure, net plasma filtration, and interstitial fluid pressure
as interstitial fluid pressure increases SO DOES LYMPHATIC DRAINAGE, which can compensate for moderate CP elevations and prevent the development of clinically apparent edema
clinically apparent edema only occurs when in for pulmonale
net plasma filtration has risen sufficiently to overwhelm the resorptive capacity of the tissue lymphatics
pt with family history of sudden death shows up with QT prolongation, what other issue do they have
NEUROSENSORY DEAFNESS
Jervell and Lange-Nielsen syndrome (AR)-
which is a congenial QT-interval prolongation often from mutations of the genes coding for cardiac cell potassium or sodium channels
pt with leukemia who recently underwent chemo and now has fungal respiratory infection with FEBRILE NEUTROPENIA (FN), typically defined as fever with absolute neutrophil could less than 500.
fever chest pain, cough, dyspnea and hemoptysis in this setting suggests what fungus
Aspergillus (Invasive pulmonary Aspergillosis)
people with profound and prolonged neutropenia are at especially high risk for viral and fungal infections, what are the two most common fungal infections found in this setting
Aspergillus and Candidia
what is Becks triad and when is it seen
hypotension with pulses paradoxes, elevated jugular venous pressure, muffled heart sounds
CARDIAC TAMPONADE
what is the Hawthorne Effect
observer effect
tendency of study subjects to change their behavior as a result of their awareness that they are being studied
commonly seen in studies concerning behavioral outcomes or outcomes that can be influenced by behavioral changes
what is berkson’s bias
selection bias reacted by choosing hospitalized patients as the control gourd (they are sicker than normal its)
what is the pygmalion effect
fact that the researchers believes in the efficacy of treatment can potentially affect outcome
(teacher told certain randomly assigned students had high IQ, teachers have higher expectation for these kids, kids perform better- probably because teacher unconsciously behaved in a way that facilitated their success)
what is seen in arginase deficiency
progressive development of spastic diplegia, abnormal movements, and growth delay in the setting of ELEVATED ARGININE DEFICIENCY
arginase is a urea cycle enzyme that produces UREA and ORNITHINE from arginine
Tx: LOW-PROTEIN DIET devoid of arginine
MILD OR NO HYPERAMMONEMIA
when is orotic acid overproduced
block in urea cycle leads to excess carbamoyl phosphate which is metabolized by dihydroorotate dehydrogenase to orotic acid
found in citullinemia and ornithine transcarbomylase deficiency
HYPERAMMONIA in boh disorders
what are the three morphological variants of pneumonia
congestion (first 24 hours)
red hepatization (days 2-3)
gray hepatizaiton (days 4-6)
resolution
what is seen the congestion stage of pneumonia
first 24 hours
affected lobe is red, heavy and body
vascular dilatation, alveolar exudate contains mostly bacteria
what is seen in the red hepatization stage of pneumonia
days 2-3
red, firm lobe (liver-like consistency)
alveolar exudate contains erythrocytes, neutrophils, and fibrin
what is seen in gray hepatizaiton stage of pneumonia
gray-brown firm lobe
RBCs disintegrate
alveolar exudate contains neutrophils and fibrin
what is seen in the resolution stage of pneumonia
restoration of normal architecture
enzymatic digestion of exudate
what happens to reverse T3 (rT3) levels in a patina with hypothyroidism being administered exogenous T3
it would decrease (as would T4) since reverse T3 (rT3) is made from peripherally converted T4 and T4 is low in this from the hypothyroidism and further negative feedback on the system
TSH is also decreased due to negative feedback
what are the more common NNRTIs
nevi rapine and efavirenz
do not require activation via intracellular phosphorylation
ADR: hepatic failure indicated by flu-like symptoms, abdominal pain, fever; SJS and TENs
what kind of drug is emtricitabine
nucleoside reverse transcriptase inhibitor (NRTI)
like zidovudine, must be converted into their monophosphate forms by cellular kinase (thymidine kinase) before they can be converted to pharmacologically active triphosphate forms
how does HBV cause hepatocellular carcinoma
integration of viral DNA into cellular genomes of the host is considered a trigger of neoplastic changes
viral protein HBx activates synthesis of insulin-like growth factor II and receptors for insulin-like growth factor I, thereby stimulating cell proliferation
HBV gene products suppress p53 tumor suppressor in host cells
