Renal transforming growth factor beta 1 production in neonate rats

Abstract. The newborn rat kidney is not fully developed until approximately 12 days after birth. In order to evaluate the possible role of Transforming Growth Factor beta 1 (TGF beta 1) in renal development we analyzed the mRNA level for TGF beta 1 in sixty Wistar rats aged 1,15 and 30 days. We also performed immunohislochemical studies to visualize the distribution of this peptide in the kidney of these rats using a TGF beta 1 antibody. The results show that the mRNA levels for TGF beta 1 are higher in the kidneys of the 1-day-old rats than in the 15 (1.4 fold) and 30-day-old rats (1.7 fold). The immunohistochemical reaction revealed the presence of TGF beta in the kidneys of the rats. The staining intensity was higher in the renal cortex than in the medulla. The data suggests that TGF beta may be important during kidney development.     

Short-term effects of ACTH on protein synthesis in adrenal cortex cells of young rats

Two units of ACTH were administered intraperitoneally to young 20 gm-rats which received an intravenous injection of L-leucine-3H thirteen min later. ACTH-injected rats, and control rats which received the isotope alone, were killed at 2-, 10-, 30- and 60-min intervals. Electron microscope autoradiographs in control animals showed strong amino-acid uptake at pulse time (2-min) in the cytoplasm of adrenal zona fasciculata cells. Label was shared between the endoplasmic reticulum (ER) and mitochondria, and a lower but still considerable uptake was seen in nucleoli. At first chase time interval (10-min) cytoplasmic labelling declined, while nuclear and nucleolar labelling increased, both changing little thereafter, and there was a 10-30 min Golgi peak. ACTH administration provoked an overall increase in amino-acid incorporation into cytoplasm, nucleus and nucleolus at pulse time, with no changes in the distribution of the reactions among organelles. Intensification of labelling was most evident over nucleoli, the grain density of which was four-times as high as in controls. The short-term increase in ER and mitochondrial protein synthesis observed after ACTH injections was considered to be consistent with the hypothesis that most newly-formed proteins in these cells may be involved in the regulation of steroidogenesis. The marked increase in nucleolar labelling suggested the presence of proteins involved in RNA synthesis.     

Physical exercise-induced changes in the core body temperature of mice depend more on ambient temperature than on exercise protocol or intensity

The mechanisms underlying physical exercise-induced hyperthermia may be species specific. Therefore, the present study aimed to investigate the effects of exercise intensity and ambient temperature on the core body temperature (T _core) of running mice, which provide an important experimental model for advancing the understanding of thermal physiology. We evaluated the influence of different protocols (constant- or incremental-speed exercises), treadmill speeds and ambient temperatures (T _a) on the magnitude of exercise-induced hyperthermia. To measure T _core, a telemetric sensor was implanted in the abdominal cavity of male adult Swiss mice under anesthesia. After recovering from the surgery, the animals were familiarized to running on a treadmill and then subjected to the different running protocols and speeds at two T _a: 24 °C or 34 °C. All of the experimental trials resulted in marked increases in T _core. As expected, the higher-temperature environment increased the magnitude of running-induced hyperthermia. For example, during incremental exercise at 34 °C, the maximal T _core achieved was increased by 1.2 °C relative to the value reached at 24 °C. However, at the same T _a, neither treadmill speed nor exercise protocol altered the magnitude of exercise-induced hyperthermia. We conclude that T _core of running mice is influenced greatly by T _a, but not by the exercise protocols or intensities examined in the present report. These findings suggest that the magnitude of hyperthermia in running mice may be regulated centrally, independently of exercise intensity.     

Beta-globin gene cluster haplotype distribution in five Brazilian Indian tribes

Haplotypes derived from five polymorphic restriction sites in the beta-globin gene cluster were investigated in 139 individuals from five different Brazilian Indian tribes by the polymerase chain reaction (PCR). Eight haplotypes were identified. Haplotypes 2 (+????) and 6 (?++?+) were the most frequent and were common to all tribes. Their prevalences ranged from 60% to 93% and from 3% to 18%, respectively. Average heterozy-gosity measured by the Gini-Simpson index is markedly reduced among these Brazilian Indians when compared with Europeans (56%), but much less (8%) in relation to Asiatics, suggesting the absence of an important bottleneck effect in the early colonization of South America. The coefficient of gene differentiation (GST′) was estimated as 0.082 among six Brazilian Indian tribes, but when only three Tupi-Mondé-speaking tribes were considered, this estimate was reduced to 0.030. © 1995 Wiley-Liss, Inc.     

Fragmentation pattern of underivatised xylo-oligosaccharides and their alditol derivatives by electrospray tandem mass spectrometry

Maltopentaose and olive pulp xylo-oligosaccharides and the correspondent alditol derivatives were analysed by ESI-MS and ESI-MS/MS. The ESI-MS spectrum of maltopentaose and maltopentaose alditols showed [M+Na]⁺and [M+H]⁺ ions. ESI-MS spectrum of xylo-oligosaccharides and their alditols showed [M+Na]⁺of neutral (Xyl_3–6) and acidic (Xyl_2–3MeGlcA and Xyl_2–3GlcA) xylo-oligosaccharides. The ESI-MS/MS spectra of maltopentaose and underivatised xylo-oligosaccharides presented fragments of glycosidic cleavages attributed to B/Z and C/Y ions. On the other hand, MS/MS spectra of the correspondent alditols showed glycosidic cleavages unambiguously identified as B-type and Y-type ions. Y-type fragment ions showed higher abundance in the MS/MS spectra of the alditol derivatives when compared to the non-reduced samples. The study of the oligoxylosyl alditols fragmentation permits to distinguish fragmentation pathways that occur both from the reducing end and from the non-reducing end of the xylan chain, allowing to obtain more information about the localization of the acidic substituent along the glucuronoxylan backbone.     

The effect of elevated hydrostatic pressure upon selected biomarkers in juvenile blackspot seabream Pagellus bogaraveo in a 14 day‐long experiment

Hydrostatic pressure elevated to 500 kPa for 14 days was found to affect hepatic 7‐ethoxyresorufin‐O‐deethylase (EROD), oxidized protein (POx), protein yield and branchial Na⁺–K⁺‐ATPase. No effect on glutathione‐S‐transferase (GST), superoxidase dismutase (SOD), catalase (CAT), lipid peroxidation (LP), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), condition factor (K) and hepato‐somatic index (I_H) was encountered.     

The Use of Mycelia of Penicilium sp. as an Ingredient for Glass Eel Nutrition

Three isoproteic and isoenergetic diets containing fish meal as a protein source (control diet) or incorporating 10 and 20% of protein from mycelia Penicilium sp. as a fish meal substitute were tested during three months for eel fingerlings growth. Some preliminary “in vitro” experiments on the L-Lysin intestinal absorption in the presence and in the absence of Penicilin (500 mg/l) after 17 h of contact show a positive effect of this antibiotic. No residues of Penicilin were detected in carcass of eels fed 7 days with 100 mg/kg Penicilin in the food. The present results show that the use of Penicilin mycelia in eels diets will have the advantage of increasing growth without any appreciable change in the quality of the carcass and also, eventually, reductions of nitrogen excretion with a positive effect in effluent quality.