In-vivo and in-vitro effects of ethanol on mouse preimplantation embryos

In Exp. 1A, hybrid mice (N = 10) were provided with food and 25% (v/v) ethanol as the only source of liquid for 72 h, beginning at the detection of the copulatory plug (08:00 h, Day 1). Control mice received food and tap water. Food consumption (P less than 0.001) but not total caloric intake (P greater than 0.05) was less for the alcohol-treated mice than the controls. Ethanol-derived calories averaged 35% of caloric intake during the 72 h of treatment. Alcohol-treated animals showed a dramatic weight loss until Day 5 while controls gained weight (P less than 0.05). Ethanol consumption did not influence pregnancy rate, litter size or litter weight. In Exp. 1B, animals were treated as in Exp. 1A, but were killed at various times between 24:00 h, Day 1, and 08:00 h, Day 4. Trunk blood was used to determine haematocrit and serum to determine alcohol concentration. Haematocrit was greater (P less than 0.05) for all alcohol-treated mice than for controls at all time periods sampled except one. Dehydration was therefore probably responsible for the weight loss seen in Exps 1A and 1B. Average blood alcohol concentrations fluctuated with time of day and day of treatment. Average maximum concentration was 91.4 mg ethanol/100 ml serum. In Exp. 2, hybrid mouse 2-cell embryos were cultured in vitro in 0 or 0.1% ethanol (Exp. 2A) and 0 or 1.0% ethanol (Exp. 2B) for 8 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Characterization of microsatellite loci for the detection of temporal genetic shifts within a single cohort of the brown demoiselle,Neopomacentrus filamentosus

Neopomacentrus filamentosus, a common damselfish on the Indo–Australian archipelago, undergoes significant shifts in size and mitochondrial genetic structure upon larval settlement and metamorphosis to juvenile stages. We characterized five polymorphic microsatellite loci in order to study temporal genetic shifts within a single generation of N. filamentosus sampled first as larval settlers then again as demersal juvenile recruits. All loci were extremely polymorphic and exhibited high levels of heterozygosity. While all loci from the larval samples conformed to Hardy – Weinberg expectations, significant heterozygote deficiencies were seen in two loci in the juvenile samples, likely due to extreme size‐selective mortality imposed post‐settlement.     

An in-depth look at pressure sores using monolithic silicon pressure sensors

Three-dimensional scalar pressure distributions were measured in solid tissue near bony prominences in vitro in meat and in vivo in pigs using silicon pressure sensors. Data are in accord with previous theoretical models and indicate that pressure is three to five times higher internally near a bony prominence than it is at the skin over the prominence. Pressure sores are thus thought to begin internally; by the time they are evident at the skin, the sore has worked its way completely from bone to skin. This conclusion is in accord with previous clinical data. Future measurement of local vector forces is needed to fully characterize the force distribution in vivo.     

Metabolism of palmitate in cultured rat Sertoli cells

Isolated rat Sertoli cells were incubated in the presence of [1-14C]palmitate at a cell concentration of 1.54 +/- 0.31 mg protein/flask (n = 7). The oxidation of palmitate was concentration dependent and maximal oxidation was obtained at 0.35 mM-palmitate. At a saturating concentration of palmitate the oxidation was linear for at least 6 h. About 65% of the total amount of palmitate oxidized during 5 h at 0.52 mM-palmitate (109 +/- 44 nmol/flask, n = 5) was recovered as CO2 and the rest as acid-soluble compounds. Almost all radioactive acid-soluble compounds which were secreted by the Sertoli cells were shown to be 3-hydroxybutyrate and acetoacetate. The palmitate recovery in cellular lipids and triacylglycerols was 9.4 +/- 5.1 nmol/flask (n = 5) and 3.5 +/- 2.8 nmol/flask (n = 5) respectively. Addition of glucose had no significant effect on palmitate oxidation but caused a 9-fold increase in esterification of palmitate into triacylglycerols. We conclude that cultured rat Sertoli cells can oxidize palmitate to CO2 and ketone bodies and that fatty acids appear to be a major energy substrate for these cells.     

Effect of Ni2+ on Ca2+-stimulated adenosine triphosphatase in the microsomal fraction of the rat parotid gland in vitro

Ni2+ inhibited Ca2+-stimulated adenosine triphosphatase activity in the microsomal fraction of the rat parotid gland in vitro. The Ni2+ concentration required for 50% inhibition was 0.45 mM. Inhibition mechanisms of Ni2+ for Ca2+ and ATP were of the competitive type and the noncompetitive type, respectively. The Ki values of Ni2+ for Ca2+ and ATP were 0.52 and 0.59 mM, respectively. The inhibitory effect of Ni2+ was reversible.