Diurnal rhythm of cytoplasmic estrogen receptors in the rat brain in the absence of circulating estrogens

The concentration of cytoplasmic estrogen receptors in the brain of ovariectomized female rats varies during the light-dark cycle. There is no variation in the affinity of the receptors for estradiol, and the rhythm is not due to estrogens from nonovarian sources. Pentobarbital reverses the reduction of receptors that occurs in the dark, and melatonin injection in the light partially mimics the action of darkness in reducing receptor levels. The factors that cause this rhythm is brain estrogen receptors may be one means by which light affects reproductive function.     

Use of aminoglycosides in surgical infections

Most infections on the surgical ward are due to one or more gram-negative rods, acting either as the sole pathogens or as principal components in a polymicrobial flora. To date, parenteral aminoglycosides have proven to be the most effective antibiotics for control or treatment of such sepsis. Unfortunately, however, serious complications as well as therapeutic failures do occur. During a 40-month period, 405 surgical patients receiving aminoglycosides (Gentamicin, Tobramycin, Sisomicin, or Amikacin) were prospectively studied with respect to: indications for antibiotic; patient population; serum concentrations of antibiotic according to route of administration, dose in mg/kg/day, and renal function; rapidity of antibiotic excretion in the urine; causative bacteria and their sensitivities to each aminoglycoside as determined by both disc and tube dilution methods; severity and frequency of drug complications; and clinical efficacy of each study antibiotic. Results supported the contention of a superior effectiveness from aminoglycosides for established abdominal and unspecified surgical infections, more rapid development of therapeutic blood levels by intravenous administration, need to alter drug dose according to frequent serum creatinine determinations, increased drug toxicity in dehydrated and shocked patients, preventability of complicating Candida sepsis, and the importance of early as well as adequate surgical debridement and drainage.     

Sterol synthesis. Syntheses of 15-oxygenated 5alpha, 14beta-cholest-7-en-3beta-ol derivatives

Treatment of 3beta-benzoyloxy-14alpha, 15alpha-epoxy-5alpha-cholest-7-ene with boron trifluoride-etherate gave, in 43% yield, 3alpha-benzoyloxy-5alpha, 14beta-cholest-7-en-15-one with the unnatural C-D ring juncture. Reduction of the latter compound with lithium aluminum hydride gave 15alpha, 14beta-cholest-7-en-3beta, 15alpha-diol and 5alpha, 14beta-cholest-7-en-3beta, 15beta-diol in 9% and 81% yields, respectively.     

Protection against acute renal insufficiency by means of forced diuresis in an ischemic rat model]

Renal ischemia of 90 min duration provokes initial oliguria and hyperazotemia; however, in rats with high diuresis, with or without renal renin depletion, protection against acute renal failure is observed in this model. The protection is directly proportional to the diuresis.     

Atherosclerotic renal artery stenosis: ostial or truncal?

PURPOSE: To evaluate a discrepancy between the location of renal artery stenoses on intraarterial digital subtraction angiographic (DSA) images and that on spiral computed tomographic (CT) angiograms. MATERIALS AND METHODS: The spiral CT angiograms and intraarterial DSA images of 40 consecutive patients with atherosclerotic renal artery stenoses were examined retrospectively. Stenoses were classified as truncal or ostial. The atherosclerotic changes in the abdominal aorta were graded. RESULTS: Fifty-eight stenoses were demonstrated. In 48 ostial stenoses, there was no discrepancy in the location of the stenoses on spiral CT angiograms and DSA images. In 10 patients, spiral CT angiography showed an ostial lesion, whereas DSA demonstrated an apparent truncal lesion. Most of these stenoses ("pseudotruncal" ostial stenoses) were in patients with severe aortic atherosclerotic disease. CONCLUSION: A renal artery stenosis at or within 10 mm of an atherosclerotic aorta at DSA may be diagnosed as an ostial stenosis.