U world test 1 block 2 Flashcards
What are the common bugs that infect joints?
N. onorrhoeae, staph, strep, Haemaphilus influenzae, and gram geg bacilli (E coli, salmonella, pseudomonas).
kids under 2- lots of H. flu
older kids and older adults- lots of S. aureus.
sickle cells- salmonella
myesthinia gravis: associated conditions; contrast with lambert-eaton
MG is a T cell dependent attack on the post-synaptic NMJ. 60-70% of pts have associated hyperplastic thymic tissue; 10-15% have thymomas.
in contrast, Lambert-Eaton is autoantibodies to presynaptic Ca channel –> decr. ACh release. may have autonomic symptoms. associated with small cell lung CA. presents with extremity weakness rather than eye or bulbar probs.
effects of DKA on serum sodium
decreased. osmotic activity of glucose (serum sodium drops 1.6 mEqL for every 100 mg/dL rise in glucose) and becase of the hyperglycemia induced osmotic diuresis, which results in sodium and free water losses. NH3 levels are high.
intraventricular hemorrhage in infants
prominent cause of brain injury in premature babies, typically within the first 5 days of life. risks; birth before 32 wks gestation, low birth weight, intrapartum asphyxia, resp. distress syndrome, and prolongued resuscitation. often begins in the germinal matrix, which is very cellular and vascular in the subventricular region that generates neurons and glia during fetal development. no network fibers are present to suppor tthe vasculature in the germinal matrix. after 32 wks, the germinal matrix has subsided in prominence, with an associated decline in cellularity and vascularity.
What are the signs of pulmonary fibrosis? Side effects of amiodarone?
dyspnea, cough, dry inspiratory crackle, and patchy interstitial infiltrate on radiography = inflammation and fibrosis in the pulm interstitum. (may be caused by amiodarone).
other side effects of amiodarone: arrhythmia, hepatic injury, thryoid abnormalities, ocular changes, and blue/grey skin discoloration
How are polypeptides anchored to the inner aspect of a plasma membrane at the carboxyl tail?
palmitoylation. process in which fatty acids are covalently anchored to plasma membrane cystein residues. that increases the hydrophobicity of the protein. many G protein coupled receptors have this modification. V2 receptor (vasopressin 2 receptor) is a great example.
How does nitroglycerin affect heart rate and end-systolic left ventricular volume?
nitro relaxes veins more than arteries and reduces preload (end diastolic vol). it also reduces the circulating blood vol via venous blood pooling. sympathetic reflexes compensate for the drop in SV, CO, and MAP with increases in HR and contractility.
overall, preload, afterload, and end systolic ventricular volume all decrease. TPR remains unchanged.
pseudohypoparathyroidism
autosomal dominant unresponsiveness of kidney to PTH. findings : high PTH, low Ca levels. shortened 4th and 5th digits. short stature, round face.
bronze diabetes presentation
d/t hemochromatosis- deposition of hemosiderin in the skin and organs. causes micronodular liver cirrhosis, DM, and skin pigmentation, as well as CHF.
presentation: 43 yo white male has incr. fatigability, dry mouth, and impotence. PE: mild hepatomegaly and atrophic testes. HIGH blood glucose.
It is NOT high serum ACTH because this exists when cortisol is LOW (most of the time). Also wouldn’t give the liver and testicular problems.
causes of impetigo
S. aureus or S. pyrogenes. highly contagious. honey colored crusting. bullous impetigo has bullae and is caused by S. aureus d/t toxin production. GAS impetigo commonly precedes post-strep glomerulonephritis.
Describe the role of the RER and the cytoplasm in protein translation.
ribosomes bind mRNA in the cytosol. proteins destined forthe ER possess an N-terminal peptide signaling sequence that identifies them as such. these N-terminal sequences are translated in the cytosol and are rapidly recognized by signal recognition particles, which halt translation and target the ribosome to the RER. signal sequences that call for protein targeting to the RER are 15-20 hydrophobic residues. deletion of the sequence would result in a failure of signal recognition peptide binding and a failure to translocate proteins to the RER.
Sertoli and Leydig cell function
Sertoli cells: support. secrete inhibit to decr. FSH, SECRETE ANDROGEN BINDING PROTEIN TO MAINTAIN LOCAL LEVELS OF TESTOSTERONE, tight junctions, support and nourish sperm, regulate spermatogenesis, produce MIF, are temp sensitivity.
Leydig cells: secrete testosterone in the presence of LH. unaffected by temp.
What signaling pathway does glucugon use? What about insulin? What other hormones use these pathways?
glucugon uses the cAMP pathway (Gs receptors). also FSH, LH, ACTH, TSH, CRH, hCG, ADH V2 receptor, MSH, PTH (FLAT ChAMP), and calcitonin, GHRH.
insulin uses intrinsic tyrosine kinase inhibitors, as do IGF1, FGF, PDGF, EGF, VEGF, etc.
(remember suprising steroid receptors: vitamin D and T3/T4)
sweat gland types and innervation
sweating is part of sympathetics.
sympathetic postganglionic nerves innervate eccrine (found in basically all skin, but esp. palms, soles, axillae). and apocrine (armpits, ears, genitals, perianal area). eccrine glands are stimulated by direct sympathetic stim; apocrine glands are stimulated by circulating catecholamines
sympathetics do not innervate sebaceous (hair oil) glands.
round ligament of the uterus
comes from the gubernaculum, which helps pull the gonads from the original position down into the pelvis. in adult males, it persists as the scrotal ligament, which secures the testes to the scrotal floor. in women, the inferior portion becomes the round ligament of the uterus (ligamentum teres uteri), which passes through the inguinal canal and attaches to the labia majora. superior portion persists as the proper ovarian ligament, which attaches the ovaries and the uterus.
