MB 3 Flashcards
patient comes in with paralysis of her lower right face, where is the damage?
UMN damage of CN7 on contralateral side
which chewing muscles are responsible for closing the mouth?
masseter, medial pterygoid, temporalis
patient comes in with paralysis of entire right side of face, where is the damage?
CN7 or facial nerve nucleus on ipsilateral side
of the gram negative rods, which are lactose fermenters?
klebsiella, e coli, enterobacter (slow are citrobacter, serratia)
how is shigella different than salmonella?
non-motile and does NOT produce H2S
once invaded, how does shigella spread to neighboring cells?
via protrusions created through host-cell actin polymerization
some strains of shigella produce shiga toxin, how does this work?
inactivating the 60S ribosomal subunit, halting cellular protein synthesis which damages intestinal mucosa
first pharyngeal arch
first aortic arch and trigeminal nerve
first aortic arch progress
regresses mostly but does contribute somewhat to the maxillary artery
second pharyngeal arch
second aortic, facial nerve, muscles facial expression, some ear and hyoid-associated structures
second aortic arch progress
regresses
third pharyngeal arch
third aortic arch and glossopharyngeal nerve, hyoid bone, sylopharngeus muscle
third aortic arch
common and proximal internal carotid arteries
fourth pharyngeal arch
fourth aortic arch, superior laryngeal branch of the vagus, many muscles of the pharynx and soft palate, few of the laryngeal muscles
fourth aortic arch
part of the true aortic arch and subclavian arteries
which pharyngeal and aortic arches are obliterated during fetal development?
fifth
sixth pharyngeal arch
sixth aortic arch, recurrent laryngeal branches of the vagus nerve, muscles of the larynx
sixth aortic arch
pulmonary arteries and ductus arteriosus
hyperthermia, muscle rigidity, confusion
neuroleptic malignant syndrome
drugs that cause NMS?
antipsychotics, which are also commonly neuroleptics
when is lithium use appropriate?
mood stabilizer, commonly in bipolar. NOT acute control of agitation and psychosis
acute lithium toxicity?
nausea, vomiting, diarrhea
propofol distribution and redistribution
first to areas of high blood flow (brain, rapid onset of drug) then fat and muscle tissues (rapid termination)
propofol vs inhaled anesthetic elimination?
propofol = liver, inhaled anesthetics = lung
what is the function of dextrans produce by strep viridans?
adherence to fibrin and platelets that are deposited at sites of endothelial trauma, providing a site for bacterial adherence and colonization during bacteremia
linkage disequilibrium
pair of alleles inherited together in the same gamete (haplotype) more often or less often than would be expected given random pairing
when does linkage disequilibrium most often occur?
when the genes are in close physical proximity on the same chromosome
6 classes of HIV anti-retroviral medications?
NRTI, NNRTI, PI, integrase inhibitor, fusion inhibitor, CCR5 antagonist
how do NRTI and NNRTIs work?
inhibit HIV DNA synthesis from RNA template by terminating DNA chain elongation - NRTI is a compteitive nucleoside/tide, NNRTI = allosteric inhibitor
PI anti-retroviral tx MOA
inhibits HIV polyprotein cleavage
Dolutegravir, raltegravir
inhibits HIV DNA integration into host genome
enfuvirtide
inhibits HIV fusion with target cell membrane by binding to HIV gp41
CCR5 antagonist
inhibits HIV entry by allosteric blocking of HIV gp120 interaction with CCR5
maraviroc
CCR5 antagonist
atazanavir, darunavir
PI - inhibits HIV polyprotein cleavage
efavirenz, nevirapine
NNRTI
pellagra
photosensitive dermatitis, diarrhea, dementia
niacin (vitamin B3) is involved in which enzymatic reactions?
as NAD and NADP, cofactors of many dehydrogenase and reductase enzymes
list enzymes that use NAD
citric acid cycle! majorly catabolic. isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, malate dehydrogenase
NK cells
destruction of cells with decreased or absent MHC class I proteins on their surfaces - virus infected cells, tumor cells
NK cell MOA
cytoplasmic granules with perforins to make holes in target cell membranes, and granzyme, chemicals that induce target cell apoptosis
NK activation
INF-gamma and IL-12
NK express what on cell surface?
CD 16 or CD 56
do neutrophils directly kill malignant cells?
NO
functions of macrophages
phagocytosis, antigen presentation to T-helped lymphocytes in association with MHC II molecules, secretion of immuno-modulatory cytokines, like TNF and IL-1
dendritic cells
avid antigen presenting cells that constantly sample their environment by endocytosis and become activatedupon encoutering a foreign antigen. When activated, DC migrante to the lymph nodes and spleen where they display antigen with MHC II and co-stimulatory molecules to activate T and B cells
CD4+ T-lymphocytes
activated by antigen presented in associated with MHC11 molecules and can promote cell-mediated (macs and CD8+ cells) and/or humoral (B-cell) responses
B cell transformation to plasma cells?
activated by Th cells, plasma cells are ready to secrete ag-specific immunoglobulins
how to NK cells kill target cells?
by inducing apoptosis
cases of GVHD
1) allogeneic bone marrow transplantation, 2) transplantation of organs rich in lymphocytes (liver), 3) transfusion of non-irradiated blood
how does GVHD happen?
donor T cells from graft survive due to donor immunosuppression and migrate into host tissues where they recognized host MHC antigens as foreign and become sensitized ; activated donor CD4+ and CD8+ T cells participate in host cell destruction
common affected areas in GVHD
skin, liver, GI
immature defense mechanisms
acting out, denial, displacement, intellectualization, passive aggression, projections, rationalization, reaction formation, regression, splitting
mature defense mechanisms
sublimation, suppression
acting out
expressing unacceptable feelings through actions
displacement
transferring feelings to a more acceptable object
intellectualization
using intellect to avoid uncomfortable feelings
passive aggression
avoiding conflict by expressing hostility covertly
projection
attributing one’s own feelings to others
rationalization
justing behavior to avoid difficult truths
reaction formation
responding in a manner opposite to one’s actual feelings
regression
reverting to earlier developmental stage
splitting
seeing others as all bad or all good; all or nothing thinking, unable to integrated positive and negative qualities into a cohesive and realistic whole; common in borderline personality disorder
sublimation
channeling impulses into socially acceptable behaviors
suppression
putting unwanted feelings aside to cope with reality
somatic symptom disorder
excessive anxiety and preoccupation with one or more unexplained symptoms
illness anxiety disorder
fear of having a serious illness despite few or no symptoms and consistently negative evaluations
conversion disorder (functional neurologic symptom disorder)
neurologic symptom incompatible with any known neurologic disease; often acute onset associated with stress
factitious disorder
intentional falsification or inducement of symptoms with goal to assume sick role
malingering
falsification or exaggeration of symptoms to obtain external incentives (secondary gain)
what is the SVC derived from embryologically?
common cardinal veins
what does each of the 3 embryo vein groups go on to become/?
umbilical vein degenerates, vitelline veins = portal system, cardinal veins = constituents of the systemic venous circulation
truncus arteriosus
ascending aorta and pulmonary trunk
esophagus
endodermal foregut
how does HCV have a lot of variation?
the virion-encoded RNA dependent RNA polymerase has no proofreading 3 –>5 exonuclease activity = many errors during replication’ marked variety in antigenic structure of envelope proteins so that host ab production continually lags behind new mutant HCV strains
differential diagnosis of vaginitis
bacterial vaginosis (gardnerella vaginalis), trichomoniasis (trichomonas vaginalis), candida vaginitis (candida albicans)
cottage cheese vaginal discharge
candida albicans
pseudohyphae
candida albicans
yellow-green frothy discharge
trichomonas vaginalis
tx for trichomoniasis
metronidazole and treat partner
tx for candida vaginalis
fluconazole
tx for bacterial vaginosis
metronidazole or clindamycin
x-ray shows hyper-inflated lungs and flattened diaphragm
COPD
emphysema
destruction of alveolar wallas and decreased lung elastic recoil, leading to increased residual volume, increased FRC and increased TLC
how do erythrocytes produce energy?
glycolysis - do not have mitochondria and thus cannot use the citric acid cycle; erythrocytes convert 1,3BPG to 2,3 BPG by way of a mutase enzyme, and2,3BPG is increased in hypoxia and chronic anemia alosterically decreasing Hg affinity for O2 so body can get as much as possible
what are 2 ways to decrease Hg affinity for oxygen?
lower blood oxygen concentrations and higher 2,3 BPG levels (indicating more energy being expended by erythrocytes
patient appearance turner syndrome
webbed neck, broad chest with widely spaced nipples, cubitus valgus, short status and primary amerrhea in woman
risks with bicuspid aortic valve
infectious endocarditis due to abnormal leaflet structure and turbulent flow
cardiac abnormalities in down syndrome
complete atrioventricular canal, ASD, VSD
sound with ASD
fixed splitting of the second heart sound
sound with VSD
holosystolic murmur at the left lower sternal border
sound mitral stenosis
mid-diastolic, low-pitched, rumbling that may being with an opening snap
sound with mitral valve prolapse
mid systolic click, often accompanied by a late systolic murmur
Marfan and Ehlers-Danlos syndrome accompanied with which heart malfunction?
mitral valve prolapse
turner heart abnormalities
aorta - bicuspid aortic valve, which are at risk of stenosis, insufficiency, infection; aortic root dilation
turner syndrome karyotype
45X
cytoplasmic inclusions in oligodendrocytes
Progressive multifocal leukoencephalopathy (PML)
passive congestion of the spleen
portal HTN, splenic vein thrombosis, CHF
can infective endocarditis lead to circulating immune complexes which can be deposited into the kidney and spleen?
YES
how does pyruvate kinase deficiency lead to hemolytic anemia?
failure of glycolysis and resultant failure to generate sufficient ATP to maintain erythrocyte structure, thus they lyse and end up in red pulp of speeln (remember: reythrocytes do not have own mitochondrion since they don’t want to consume the oxygen they carry, so instead they produce ATP through glycolysis)
ataxia telangiectasia
triad = cerebellar ataxia, telangiectasis, increased risk of sinopulmonary infections; risk of hematologic malignancies; causes immune deficiency of cell-mediated and humoral (especially IgA deficiency), predisposing to upper and lower airways
what is telangiectasias
widened venules which cause thread-like red lines on the skin
ataxia telangiectasia inheritance?
AR; ATM gene mutation, responsible for DNA break repair
how does lead intoxication cause hypochromic anemia?
inhibition of mitochondrial iron transport important for here synthesis
Lesch Nyhan Syndrome
x-linked recessive results in HGPRT enzyme deficiency = defective purine catabolism = severe hyperuricemia and gout
behavior of someone with Lesch Nyhan Syndrome
self-mutilating, mental retardation, choreoathetoid movements, spasticity
bare lymphocyte syndrome
immunodeficiency resulting from a defect in expression of HLA class II antigens on the surface of APCs, result = no cell-mediated response and no humoral response
Niemann-Pick disease
AR, defect in sphingomyelinase leading to accumulation of sphingomyeling within monocytic cells leading to death in early childhood
two disease with a cherry red spot on the macula
niemann-pick disease and tay-sachs disease
gag protein
p24 = capsule for HIV
env protein
gp 41 (transmembrane protein of envelope) and gp 120 (outer glycoprotein that gets in touch with host)
pol protein
RT polymerase to transfer positive RNA to DNA
what microbes infect macrophages?
HIV and mycobacterium
CD4 < 200
HIV progresses to AIDS
HIV caused CA
diffuse large B cell lymphoma
HIV virus interacts with what host cell proteins?
early = CCR5, later = CXCR4
HIV diagnosis?
Eliza first with follow-up western blot
