Basic Science Flashcards
FRAX score calculates the clinical risk of fracture using
bone mineral density of the femoral neck, BMI, current smoking activity, history of parental hip fracture, and prior personal history of fracture before age 50.
PHEX
responsible for X-linked hypophosphatemic rickets
CLCN7 and TC1RG1
mutations cause osteopetrosis
BMP signaling mech
binds serine/threonin kinase receptor then triggers SMAD which upreg transcription
MRSA resistance mech
mutation mecA encoding an altered penicillin binding protein
Beta-lactam antibiotics
Penicillin, Cephalosporins inhibit bacterial peptidoglycan synthesis = bac cell wall synthesis
Aminoglycosides
Gentamycin, Tobramycin inhibit protein synthesis (via binding to cytoplasmic ribosomal RNA)
Clindamycin and Macrolides
Clindamycin, Erythromycin, Clarithromycin, Azithromycin inhibit the dissociation of peptidyl-transfer RNA from ribosomes during translocation (they don’t ask about this one a lot)
Tetracyclines
inhibit protein synthesis
Glycopeptides
Vancomycin, Teicoplanin interfere with the insertion of glycan subunits into the cell wall
Rifampin
inhibits RNA synthesis (you can remember that because they both start with the letter “R”)
Quinolones
Ciprofloxacin, Levofloxacin, Ofloxacin inhibit DNA gyrase - they ask a lot about this one
Oxazolidinones
Linezolid inhibits protein synthesis by blocking formation of the 70S ribosomal translation complex . Ribosomal activity- Linezolid can cause serotonin syndrome (abdominal pain, headache, diarrhea, and clonus, unresponsive pupillary reaction, tachycardia, hypertension, tremor, and clonus.) Give Benzo to decrease reaction
Steroids in spinal cord injury have been shown to do what with regard to edema and hemmorhage?
just prevent exent of hemmorahge, not correlated with outcome. no effect on edema
Wheelchair Spinal cord injury: C4,5,6,7
C4 injury needs puffer control; C5 can use hand controls; C6 can use a manual wheelchair and sliding board transfers; C7 allows independent transfers
Asia Scale
ASIA A: complete spinal cord injuries. ASIA B: are incomplete injuries and have preserved sensory but no motor function. ASIA C: are incomplete injuries characterized by greater than half of the key muscle groups below the neurological level with muscle grade less than 3. ASIA D: are incomplete injuries characterized by at least half of the key muscle groups below the neurological level with muscle grade greater than 3. ASIA E: implies normal motor and sensory function.. E has Everything
malignant peripheral nerve sheath tumor
4% incedence with NF-1 (AD). spindle cell, stains with S100. Tx wide resection +radiation
TGF-β1 and muscle injury
causes fibrosis
MOM THA cause of pseudotumor
MOM THA: pseudotumors occur more often with increased wear attributable to edge loading. Not lymphocyte activity to metal
Rickets effect what zone
Rickets: Due to defective mineralization in zone of provisional calcification. Xrays: Increased physeal width, metaphyseal cupping, bowing. First line deformity treatment- medical (improves physes & alignment)
Familial Hypophosphatemic or Vit D resistant Rickets
Also known as “Vitamin D- resistant” rickets or phosphate diabetes. Due to impaired renal tubular phosphate absorption. X linked dominant (usually, also AR, AD). Treat with vit D(1,25 dihydroxy vitamin D3 (calcitriol)) & phosphate
Hypophosphatasia Rickets
Autosomal recessive. Due to defect in alkaline phosphatase. Labs- low alkaline phosphatase and high urinary phosphoethanolamine
Nutritional/Vit D deficient
Occurs in premies, exclusively breast-fed, intestinal malabsorption. Genu varum, hypotonia, height< 5th percentile. RX with vit D (5000 IU daily)
T-score
T-scores are defined as standard deviations from normal peak bone mass (young adults). Osteoporosis is defined as a T-score of -2.5 or below as defined by the WHO, and osteopenia is defined as a T-score between -1.0 and -2.5