Isolation of microsatellite loci in the Capricorn silvereye,Zosterops lateralis chlorocephalus (Aves: Zosteropidae)

The Capricorn silvereye (Zosterops lateralis chlorocephalus) is ideally suited to investigating the genetic basis of body size evolution. We have isolated and characterized a set of microsatellite markers for this species. Seven out of 11 loci were polymorphic. The number of alleles detected ranged from two to five and observed heterozygosities between 0.12 and 0.67. One locus, ZL49, was found to be sex‐linked. This moderate level of diversity is consistent with that expected in an isolated, island population.     

Effect of change in particle number on pulmonary clearance of aerosolized 99mTc-DTPA

Pulmonary clearance (PCl) of inhaled aerosolized 99mTc-diethylenetriamine pentaacetic acid (DTPA) across the alveolocapillary membrane is diffusion limited. Therefore, if the mixing of the 99mTc-DTPA in the aqueous hypophase underlying surfactant is slow or incomplete or if there were no hypophase, an increase in the alveolar surface area occupied by 99mTc-DTPA particles would increase the absorption rate. The aim of this study was to examine whether there is an effect on PCl of changing the number of inhaled particles. The change in particle number was accomplished by a setup of four parallel jet nebulizers feeding a central delivery chamber of 400 cm3. We performed two kinds of experiments in eight healthy nonsmokers between 28 and 52 yr of age. In the first experiment, 99mTc-DTPA in saline was nebulized in one nebulizer, while saline was nebulized in the other three. In the second experiment the number of inhaled particles containing 99mTc-DTPA was increased by a factor of four by nebulizing 99mTc-DTPA in saline in all four nebulizers simultaneously. Increasing the number of inhaled 99mTc-DTPA particles caused an increase in PCl of 24.2% (P less than 0.01). We conclude that there is a slight but significant effect of changing the number of DTPA particles on PCl and that this is probably due to an uneven mixing of the 99mTc-DTPA in the aqueous hypophase underlying the surfactant lining and the alveoli.     

Termination of pregnancy in cases of fetal death in utero by intravenous prostaglandin F2alpha.

Delivery was induced by an intravenous infusion of prostaglandin F2alpha (PGF2alpha) in gradually increasing doses in 30 consecutive cases of fetal death in utero after the 28th week of gestation. Twenty patients delivered during the first day of prostaglandin administration, 9 on the second day, and 1 patient not until the third day of infusion. It is concluded, that intravenous PGF2alpha appears to be superior to oxytocin in termination of pregnancy under these conditions.     

Secretion of lipoprotein lipid and synthesis of fatty acids, cholesterol and triacylglycerol by hepatocytes of fasted-refed rats

Synthetic rates of fatty acid, cholesterol and triacylglycerols, and contents and secretion of lipoprotein lipids, were determined in hepatocytes of rats fed ad libitum a fat-containing stock diet or of rats fasted for 48 h and then refed for 24 or 48 h with stock diet or with a glucose-rich fat-free diet. When compared with the values for the ad libitum-fed rats, fatty acid synthesis was lower in fasted rats, slightly increased in rats refed with the stock diet, but several-fold elevated after refeeding the glucose-rich fat-free diet. Cholesterol synthesis was decreased in the fasted cells, and restored to the control level upon refeeding either diet. Triacylglycerol synthesis from exogenous oleate was greatly stimulated in the cells of fasted-refed rats above the rate in cells of the ad libitum-fed rats, the increase being considerably higher after refeeding the glucose-rich fat-free diet than the stock diet. The amount of triacylglycerol secreted by the cells was also elevated by the fasting-refeeding treatment, but the difference between the two diets was much less pronounced than seen for the lipids' synthetic rates. This imbalance may underlie the huge accumulation of this lipid observed in the heptatocytes after refeeding the rats for 48 h with the glucose-rich fat-free diet.     

Characterization of human platelet basic protein, a precursor form of low-affinity platelet factor 4 and beta-thromboglobulin

Platelet basic protein (PBP) was purified from the supernatant of thrombin-stimulated, washed human platelets by ion-exchange, affinity, molecular sieve, and high-performance liquid chromatography (HPLC). The NH2-terminal amino acid sequence was determined by automated Edman degradation, revealing 9 unique residues followed by 10 residues of the established low-affinity platelet factor 4/beta-thromboglobulin (LA-PF4/beta TG) sequence. Among the nine were three basic residues, accounting for the high isoelectric point of PBP. Additional evidence for precursor status includes the immunological cross-reactivity of all three species and the ability of plasmin and trypsin to produce from PBP a species resembling beta TG in charge, hydrophobicity, and size. Tryptic peptide maps of PBP and LA-PF4 obtained by reverse-phase HPLC were very similar, and from each protein, a peptide was isolated which showed the amino acid composition predicted for the COOH-terminal tryptic peptide of beta TG. Normal platelets contained predominantly LA-PF4, with PBP ranging from 10% to 30% of total beta TG antigen. This was true even when fresh platelets were lysed with trichloroacetic acid in order to provide the most complete and rapid inhibition of proteolytic activity. beta TG itself was never detected in this situation or in the release supernatant of stimulated platelets, and only rarely in unprotected lysates. In agreement with earlier results, crude preparations of PBP were mitogenic for 3T3 cells, but highly purified preparations of PBP and LA-PF4 were free of this activity.     

Ethanol stimulates formation of leukotriene C4 in rat gastric mucosa

Ethanol-induced gastric mucosal damage is characterized by microcirculatory changes such as statis and plasma leakage. Sluggish blood flow and statis have also been observed after administration of exogenous leukotriene (LT) C₄. The effect of ethanol on the release of LTC₄ from rat gastric mucosa was therefore investigated. It was found that intragastric instillation of ethanol increases gastric mucosal release of LTC₄ in a dose- and time-dependent manner parallel to the production of gastric lesions. The lipoxugenase inhibitor nordihydroguaiaretic acid (NDGA) and the anti-ulcer drug carbenoxolone (CX) inhibited mucosal release of LTC₄ and simultaneously protected against gastric damage caused by ethanol. It is concluded that increased formation of LTC₄ and /or other 5-lipoxygenase-derived products of arachidonate metabolism may be involved in ethanol-induced gastric damage. Furthermore, inhibition of the 5-lipoxygenase pathway may be an important mechanism of action of gastric protective drugs.     

Approximate case influence for the proportional hazards regression model with censored data

A method is presented for approximating the influence of individual cases upon regression coefficient estimates obtained from the Cox proportional hazards model. Observations can thus be identified which may greatly influence statistical inferences regarding the effects of prognostic factors upon survival time. An example from a cancer clinical trial is given.