Analyse numérique des 50 espèces classées dans le genre Pichia (Ascomycetes). Seconde application d'une méthode d'analyse factorielle

A second application of factor analysis among the 50 species of genusPichia corroborates the already identified three groups and underlines the non-appartenance of round-sporedPichia species to genusPichia sensu stricto. These results are compared with Campbell's numerical analysis.     

Imipramine and lipid phase transition in inner mitochondrial membrane

As ascertained by freeze-fracture electron microscopy, imipramine prevents lateral phase separation from taking place in inner mitochondrial membranes at sub-zero temperatures. Electron spin resonance (ESR) measurements performed on mitochondrial membranes labeled with the N-oxyl-4′,4′-dimethyloxazolidine derivative of 16-ketostearic acid, show that the spin probe motion is markedly inhibited below 0°C and that 5 mM imipramine attenuates the temperature effect. These results are explained by supposing that imipramine is able to decrease the transition temperature of the inner mitochondrial membrane lipids as it does for simple lipid systems.     

Opioid agonist and antagonist bivalent ligands as receptor probes

Bivalent ligands are molecules which contain two pharmacophores linked by a connecting chain (spanner). The present report describes the use of oxymorphamine (Oxy) and naltrexamine (Nal) as the opioid agonist and antagonist pharmacophores separated by a variable length spanner composed of succinyl-bis-oligoglycine. The agonist series, [CH2CO(Gly)nOxy]2, and antagonist series, [CH2CO(Gly)nNal]2, were synthesized (n = 0-4) and tested on the electrically stimulated GPI. All of the antagonist bivalent ligands (Nal) antagonized the effects of morphine, with the greatest potency enhancement (60 x) residing with the succinyl (n = 0) congener. A dramatically different SAR profile was observed in the agonist (Oxy) series where the greatest potency enhancement (17 x) occurs when n = 2. By contrast with the antagonist series the agonist bivalent ligand with n = 0 is equipotent to its monovalent agonist analogue. The significance of these results with respect to the possibility of discrete opioid agonist and antagonist recognition sites are discussed.     

Modulation of antinociceptive responses following tail pinch stress

Mild, non-noxious, oscillating pinches to a rat's tail elicits hyperphagia. The present study examined whether tail-pinch (TP) would exert hyperalgesic and hyperactive effects in rats that also exhibit the overeating response. The first experiment assessed TP effects upon reactivity to electric shock as measured by flinch-jump thresholds. Significant decreases in jump thresholds were observed 0 and 15, but not 30, min following TP. This effect persisted regardless of whether food was present or absent during TP. The second experiment assessed TP effects upon reactivity to heat as measured by hot-plate latencies. In contrast to jump thresholds, the shortened hot-plate latencies observed following TP persisted into the recovery period. In examining TP effects upon activity levels (Experiment 3), it was found that animals display similar patterns of temporally-declining activity regardless of whether TP was administered or not. Finally, TP selectively decreased the analgesic responses to two different doses of morphine and two different cold-water swim temperatures (Experiment 4). The TP-induced reductions occurred when TP was administered either before or after the analgesic manipulation. These data are discussed in terms of the nociceptive selectivity of the TP effect, and its influences upon analgesic processes.     

Dietary and Physical Activity Correlates of Long-Term Weight Loss

Covariations in body mass index (BMI), physical activity, macronutrient intake, and the frequency of consumption of specific foods were examined among 82 men and 75 women participating in a behavioral weight loss program over a period of 18 months. Results of repeated measures analyses of covariance showed that BMI change was inversely related to change in physical activity and change in frequency of vegetable consumption. BMI change was positively related to change in calorie intake from fat and change in frequency of consumption of beef, hot dogs, and sweets. Change in fat calories predicted BMI change better than change in total calories. In addition, change in the frequency of consumption of specific foods accounted for a larger percentage of the variance in BMI change than did change in macronutrients (10.4% vs. 5.2%). No differences were found between predictors of weight loss vs. weight maintenance.     

Disruption of mitochondrial functions involving mitochondrial permeability transition pore opening caused by maleic acid in rat kidney

Journal of Bioenergetics and Biomembranes - Propionic acid (PA) predominantly accumulates in tissues and biological fluids of patients affected by propionic acidemia that may manifest chronic renal...     

A fungal glycoprotein mitigates passion fruit woodiness disease caused by Cowpea aphid-borne mosaic virus (CABMV) in Passiflora edulis

BioControl - Passion fruit woodiness disease is responsible for severe losses in passion fruit production around the world. The disease is caused by Cowpea aphid-borne mosaic virus (CABMV), an...     

Synthesis,biological evaluation and molecular modeling of novel selective COX-2 inhibitors: sulfide,sulfoxide, and sulfone derivatives of 1,5-diarylpyrrol-3-substituted scaffold

A novel series of 1,5-diarylpyrrol-3-sulfur derivatives (10–12) was synthesized and characterized by NMR and mass spectroscopy and x-ray diffraction. The biological activity of these compounds was evaluated in in vitro and in vivo tests to assess their COX-2 inhibitory activity along with anti-inflammatory and antinociceptive effect.Results showed that the bioisosteric transformation of previously reported alkoxyethyl ethers (9a-c) into the corresponding alkyl thioethers (10a-c) still leads to selective and active compounds being the COX-2 inhibitory activity for most of them in the low nanomolar range. The oxidation products of 10a,b were also investigated and both couple of sulfoxides (11a,b) and sulfones (12a,b) showed an appreciable COX-2 inhibitory activity. Molecular modeling studies were performed to investigate the binding mode of the representative compounds 10b, 11b, and 12b into COX-2 enzyme and to explore the potential site of metabolism of 10a and 10b due to the different in vivo efficacy. Among the developed compounds, compound 10b showed a significant in vivo anti-inflammatory and antinociceptive activity paving the way to develop novel anti-inflammatory drugs.