UWSA 1 Flashcards
Where is AV node anatomically located?
Intratrial septum near tricuspid valve
Where is SA node anatomically located?
RA near SVC
What is order of length of conduction from fastest to slowest?
PAVA Purkinje fibers (bundle of HIS) 2.2m/sec Atrial muscle 1.1 m/s Ventricular muscle 0.3 m/sec AV node (slowest at 0.05 m/s)
What bone condition is associated with Paget’s disease?
Osteosarcoma. Lysis and sclerosis of bone, focal periosteal elevation, Codman’s triangle, subburst pattern of soft tissue adjacent to bone
Which vitamin is teratogenic in 1st trimester?
Vit A- spontaneous abortion and fetal defects, cardiac anomalies, microcephaly, early epiphyseal closure, growth retardation
MOA oseltamivir?
Inhibits neuraminidases that inhibit cleaving of sialic acid and release of viral particles
What is DNA laddering?
Appearance of DNA fragments on gel electrophoresis. Malignant cells overexpress BCL2 antiapoptotic protein and so their endonucleases don’t work- the fragments will remain uncleaved
***DNA laddering –> BCL2 –>Evasion of apoptosis
What does Ach do to smooth muscle in lungs? Which receptors are activated?
Causes contraction via stimulation of M3 receptors
MOA physiostigmine?
AchE inhibitor - will increase levels of Ach and cause bronchoconstriction
Which drug blocks the action of M3 receptors in lung?
Atropine - competitive muscurinic receptor antagonist
Will act as anticholinergic agent and decrease the effects of Ach (decreased smooth muscle constriction)
What are SE of benzos? Who gets them
Elderly people who have slower CYP hepatic oxidative reduction
Confusion, anterograde amnesia, falls, ataxia
What are signs of anticholingergic toxicity?
Mad as a hatter, hot as a hare, blind as a bat, red as a beet, dry as a bone, full as a flask, fast as a fiddle
Mydriasis, urinary retention, dry, flushed skin, confusion/hallucinations, tachycardia, hyperthermia, decreased sweat and salivation
Which drugs cause anticholingeric toxicity?
Jimson weed (seeds)
Atropine (M3 antagonist), scopolamine, hyoscyamine
If genetic mutation is present in offspring, but not in parents, what occurred?
Germline mosaicism
What will you see on smear for AML?
Auer rods
What is translocation in AML?
15;17
What is Tx for AML?
All trans-retonoic acid
What are initial symptoms of AML?
Pancytopenia- weakness, fatigue, bleeding gingiva, easy bruising
DIC
Which cells secrete IL-2? What is function?
T-cells that have been activated by antigens
IL-2 stimulates growth of other white cells- NK cells, B cells, T cells, macrophages
What transmembrane proteins are used for epithelial cells to adhere to one another?
Cadehrins- form desmosomes and adherens junctions. They are calcium-dependent & will not adhere without extracellular Ca2+
What will you see on histology for molluscum contagiosum (pox virus)?
Cytoplasmic inclusion bodies- eosinophilic cytoplasmic inclusion bodies made of viral particles
What stimulates bile and bicarbonate release?
Low duodenal pH
What muscles are near the popliteal artery?
Adductor magnus and soleus
Sublimation? (psych)
Channelling impulses into socially acceptable behaviors ( never drinking because your dad drank)
What does ligand binding to tyrosine kinase receptor do?
Causes **dimerization* of two identical receptor subunits that then undergo conformational change to expose tyorsine kinase active sites
MOA phosphodiestrase-5 inhibitors?
Increase cGMP and cause SM vasodilation in corpora cavernosa
What muscle is paralyzed in winged scaupla? Innervation?
Serratus anterior, rotates scapula upward
Long thoracic nerve. Lymph node dissection or chest tube placement can sometimes damage nerve
What does pancreas secrete in response to secretin?
Bicarbonate
As flow rate increases, what electroyltes are secreted from pancreas?
Bicarbonate and Na+
Bicarb and Cl have inverse flow relationship due to Cl-/HCO3- exchanger
Duration of acute stress disorder vs PTSD?
ASD = 3 days to 1 month
PTSD > 1 month
What are categories in punnet square for determining TP, TN, FP, FN?
Diseased and non-diseased
vs + test and - test
Equation for false positive rate?
(1-specificity)
How do you calculate RR?
RR = (diseased/total in group A)/(diseased/total in group B)
Equation NNT?
1/ARR
Calculation for ARR?
Control Event rate - experimental event rate
Patient with port wine colored urine, abdominal pain, n/v, peripheral neuropathy. What is it?
Porphobilinogen deaminase deficiency
Acute intermittent porphorya (defective heme synthesis
No skin photosensitivity*
Usually occurs after oxidative stress (medications)
How is retinoblastoma caused by hereditary disease?
2 hit hypothesis
RB1 gene already mutated
A second mutation causes the disease from spontaneous somatic mutation
Bilateral mutlifocal retinoblastoma + osteosarcoma
Most common cuase of septic arthritis?
Staph aureus & N gonorrhea
What are WCC like for people with digeorge? Which infections will they get
Dysplastic thymus –> Abnormally low T cells (CD3+) but normal B cells
Fungal infections - Candida and P Jirovecii
What is chiari malfomation I?
Displacement of cerebellum through foramen magnum
Occipital headaches, ataxia, worse with physical activity
46XY with female karyotype. Vagina ends in blind pouch. What is it?
Complete androgen insensitivity syndrome
What are labs in 5-alpha reductase deficiency? Presentation?
Ambiguous genetalia
Testosterone/DHT ratio elevated
What receptors are found in adrenal medulla?
Alpha1 and Beta 1 (responsible for catecholamine release and HTN)
MOA Phenoxybenzamine? When do you use it?
Irreversible Alpha-1 inhibitor. Before pheochromocytoma surgery to avoid hypertensive crisis
Don’t give beta-blockers because they increase the action of Alpha-1 receptors in periphery
What structure in the brain is responsible for neonatal IV hemorrhage?
Germinal matrix (dense cellular and vascular layers where neurogenesis occurs). Bleeds into ventricles
What does amiodarone do to lung?
Interstitial pneumonitis
What is misoprostol used for? MOA?
Prostaglandin E1 analogue, decreases gastric acid secretion. Can treat peptic ulcers
Cervical ripening in pregnancy
How do NSAIDs lead to asthma and respiratory disease?
Inhibit COX pathway and cause increased production of leukotrienes
Where do squamous cell carcinomas due to smoking occur in head/neck?
Ventral tongue, floor of mouth, lower lip, soft palate, gingiva. Mets to submandibular area
Effect of nitrates on HR and end diastolic volume?
Decreased EDV, increased HR (due to reflex tachycardia)
What is electrolyte composition in sweat and mucous for CF patients?
High Cl in sweat
Low Cl and Na in mucous
What are the stages of mRNA processing?
5’ capping - stabilizes 5’ mRNA in cytosol
PolyA trail addition- stabilizes 3- in cytosol
Splicing out of introns (causing DNA loops) by snRNPs***
What is allelic heterogeneity?
Same disease, but different genes causing it
Man with hyperpigmentation, derranged LFTs, arthralgia, Diabetes, cardiomyopathy. what is it?
Hemochromatosis- autosomal recessive disease of excess iron stores. Excessive GI absorption of iron
How does cirrhosis cause splenomegaly?
Portal venous system congestion, increased backpressure into splenic vein (valveless system)
Burn victim with yellow crusting on wound. What is organism?
Staph or strep- impetigo- yellow crust
What is cell mechanism for multidrug resistance?
Bacterial antibiotic efflux pumps using ATP, proton electrochemical gradients, and sodium gradients**
Which gene is affected in achondroplasia?
FGFR3 - restricted chondrocyte proliferation
What are White cells like in X-linked burton agammalobinemia?
No B cells, present T cells
Intracellular messaging abnormality
Where do insulin N-terminal peptide sequence proteins accumulate in someone with diabetes?
Proteins accumulate in cytosol.
Normally translated –>ER cleaves preproinsulin into proinsulin–>Golgi–>cleavage of proinsulin–> exocytosis of insulin and C peptide
What accumulates in maple syrup urine disease?
Branched chain amino acids
What enzyme and vitamin is deficient in MSU disease?
Alpha ketoacid dehydrogenase Requires B1 (thiamine) as a cofactor
What type of cells secrete andorgen binding protein in males? Why is this important?
Sertoli cells secrete them in order to maintain high concentrations of testosterone in epydidymis and seminiferous tubules so that spermatogenesis can occur
Signaling path for glucagon?
Stimulates Gs –>adenylate cyclase–>cAMP–>
glygocenolysis & gluconeogenesis
What is signaling path for insulin?
Tyrosine kinase receptor —> phosphoinositide 3-pathway –> increases glucose uptake in tissues, increasess glcogen synthesis, decreases gluconeogenesis
What type of collagen is affected in OA?
Type II collagen - haline cartilage
What is pathogenesis of OA?
Increased biomechanical stress and metalloprotease activity
What are clinical signs of pulmonary artery hypertension?
Pitting edema, RV hypertrophy, R ventricular heave
Due to pulmonary endothelial dysfunction** hyperplasia of intimal layer
What enzyme is deficient in neonatal hypoketotic hypoglycemia?
Medium chain Acyl-CoA dehydrogenase deficiency. No formation of Acetyl-CoA to form ketone bodies. Fatty acids usually oxidized to form ketone bodies
What genes are associated with 2-hit hypothesis (tumor supressor genes?)
VHL, BRCA1/2, APC, TP53, RB, WT1
What genes are associated with gain of function (proto-oncogenes?)
RAS, MYC, ERBB1/2, HER2, ABL, BRAF
What are internal ribosome entry sites?
Part of programmed cell death when a specific nucleotide sequence (internal ribosome entry) will attract eukaryotic mRNA and allow it to be translated in middle of sequence
MOA piolitazone?
Thiazolidinediones (PPAR-y activators)
-Decrease insulin resistance by upregulating genes for GLUT4 and adiponectin (fatty acid oxidation)
SE of pioglitazone?
Fluid retention, weight gain
No hypoglycemia
MOA dapaglifozin?
SGLT-2 inhibitor- inhibits glucose reabsorption
MOA sulfonylureas (glyburide) and meglitinides (repaglinide)?
Block K+ ATPase in pancreatic beta cells, causing depolarization of L-type calcium cannels, releasing insulin
What is main treatment for hepatic encephalopathy?
Lactulose (intestinal acidification to create lactic acid and acetic acid)
Which antibiotic interacts w warfarin?
SMP-TMX, it inhibits CYP 450 which then increases effect of warfarin (must lower dose of warfarin if giving SMP-TMX)
What are second messengers for Alpha 1/2, Beta 1/2 receptors?
Alpha 1 - increases IP3
Alpha 2- decreases CAMP
Beta 1 increases CAMP
Beta 2 increases CAMP
What part of bone is affected in osteomalacia?
Decreased mineralization of OSTEOID** in Haversian canal
Early onset malignancies- sacoma, breast, brain, adrenal, leukemia. What happened to their genes?
p53 two hit hypothesis - inactivating mutation on an alelle
What does recurrent laryngeal nerve supply?
all intrinsic muscles except for cricothyroid (superior laryngeal nerve)
What type of thyroid condition causes huge germinal centers to appear?
Hashimoto thyroiditis
What type of inheritence is duchenne muscular dysrtrophy?
X linked recessive
What causes achalasia?
Absence of esophageal peristalsis in distal esophagus. Degeneration of inhibitory ganglion cells in myenteric plexus
Who gets G6PD?
Africans, asians, mediterranians
What type of neurons are unmyelinated?
Slow pain, heat, and olfaction. Post-ganglionic autonomic nerves
Describe antigen processing in APC cell process?
MHC II made of alpha and beta subunits
These are brought together by invariant chain and they go through RER and Golgi body to form a new complex that can be presented to T cells
What are symptoms of iron deficiency anemia?
Glossal pain, dry mouth, tongue papillae atrophy, alopecia
What happens cellularly when cardiac hypertrophy occurs?
Increased rate of myosin mRNA suynthesis
What layer of skin thickens when you get a callous?
Stratum corneum
MOA doxycycline?
Tetracycline, inhibits 30S ribosomal unit
MOA eurythromycin?
Binds 50s subunit
what determines cellular differentiation and de-differentiation?
Transcription factors
What does cholingergic stimulation do to eye?
Muscurinic agonists. Pupillary constriction (pilocarpine is a cholinomimetic)
What is pernicious anemia? Result?
Autoimmune descruction of gastric mucosa. Hypochloridia, decreased gastric acid, increased gastrin levels, decreased intrinsic factor and B12
Does varicocele transilluminate?
No. Only bulges when standing up not lying down
What are heart abnormaliies in Digeorge syndrome?
ToF, TA, interrupted aortic arch
What is result of CD40L deficiency? What is inheritance pattern?
X linked recessive
Inability to class switch, hyperIgM syndrome
Low IgA, IgG, IgE
Normal B and T cell count
Alpha 1 receptors peripherally have what type of messenger system?
Phosphatidylinositol 2nd messenger system
Gq–>phospholipase C –> inositol triphosphate (IP3)*** release, DAG, IP3 liberates calcium in ER and leads to smooth muscle contraction
What substances use cGMP as a second messenger?
BNP, ANP, NO
What do etanercept and infliximab target?
Anti-TNF-alpha agents. Used in autoimmune conditions
What organism does methenamine silver stain look for?
Aspergillus. Broomlike appearance. fungus balls in lng cavities
What do HOX13 genes do?
Determine where hand-foot-genitals go. Deformity results in malformations
How does afterload affect contraction velocity?
Decrease in afterload increases contraction velocity
Where do the maxillary sinuses drain?
Middle nasal meatus
What part of the sarcomere lengthens and shortens during muscle contraction and relaxation?
I- band containing thin actin filaments (and Z line)
