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V Girard

Publications and source records attributed to V Girard.

34 records · Page 2Linked to original sources

Juice-extracted grass pellets and sodium bicarbonate for cows in midlactation fed timothy grass silage.

Eighteen midlactation Holstein cows, averaging 80 to 125 d of lactation, were used in a trial of switchback design to evaluate two timothy silages, wilted or direct-cut and treated with formic acid, and three treatments, control, NaHCO3 added at 2% of DM, or juice-extracted grass pellets replacing 30% silage DM. Cows fed direct-cut silage that had been treated with formic acid consumed more DM (19.8 vs. 18.6 kg/d) than those fed wilted silage. The DMI was also increased with NaHCO3 and grass pellet treatments. However, NaHCO3 reduced digestibility of most nutrients without affecting pH of rumen fluid or degradation of DM and NDF. Compared with wilted silage, direct-cut silage that had been treated with formic acid contained more degradable NDF (86 vs. 84.5%). Milk yield (24.9 vs. 23.6 kg/d) was higher for cows fed direct-cut than wilted silage, but 4% FCM yield remained unchanged. Addition of NaHCO3 tended to increase yields of milk and 4% FCM. Treatments did not affect milk composition. Serum urea N was higher for cows fed the direct-cut silage than for cows fed wilted silage. Silage type had more impact on feed intake and performance than did NaHCO3 or juice-extracted grass pellets.

Animals↗

Antitussive effect of SR 48968, a non-peptide tachykinin NK2 receptor antagonist.

The antitussive effects of SR 48968, a non-peptide tachykinin NK2 receptor antagonist, were investigated on citric acid-induced cough in the unanesthetized guinea-pig and compared with the effects of codeine. SR 48968 (0.01-0.3 mg/kg i.p.) inhibited in a dose-dependent manner the number of coughs induced by inhalation of an aqueous solution of citric acid with an ED50 of 0.1 mg/kg (0.17 mumol/kg). Under similar conditions, the codeine ED50 was 8 mg/kg (27 mumol/kg). Naloxone, an opioid receptor antagonist, abolished the effects of codeine but did not modify the effects of SR 48968. These data suggest that NK2 receptor stimulation might play an important role in the regulation of the cough reflex and that SR 48968 could be a potential antitussive agent.

Animals↗

Separation and Partial Purification of 1,3-beta-Glucan and 1,4-beta-Glucan Synthases from Saprolegnia.

Enriched 1,3-beta-glucan and 1,4-beta-glucan synthase fractions from the fungus Saprolegnia were isolated by rate zonal centrifugation on glycerol gradient. Purification was improved by entrapment of the enzymes in their reaction product, i.e. microfibrillar glucans. 1,3-beta-Glucan synthases were separated from 1,4-beta-glucan synthases following resuspension of entrapped enzymes. Sodium dodecylsulfate-polyacrylamide gel electrophoresis indicated that 1,3-beta-glucan and 1,4-beta-glucan synthases may have a different polypeptide composition because they were enriched for different protein subunits (34, 48, and 50 kD for the 1,3-beta-glucan synthase and 60 kD for the 1,4-beta-glucan synthase).

Journal Article↗

Modulation of Pea Membrane beta-Glucan Synthase Activity by Calcium, Polycation, Endogenous Protease, and Protease Inhibitor.

beta-Glucan synthase activity in plant membranes can be markedly altered by a multiplicity of apparently unrelated factors. In pea epicotyl membranes it is enhanced by low and inhibited by high concentrations of added Ca(2+), trypsin or soluble pea protease. Ca(2+) stimulates preexisting synthase activity, particularly in the presence of polycations (spermidine), but protease treatments activate and, with time, inactivate synthase zymogen. Endogenous pea protease activity is also associated with washed pea membrane and appears to be responsible for the decay observed with time in the beta-glucan synthase activity. Endogenous pea protease activity is inhibited by thiol inhibitors, e.g. iodoacetamide and Hg(2+), and by a heat-stable peptide, molecular weight approximately 10,000, that is found in supernatants of pea extracts. These protease inhibitors have the capacity to protect beta-glucan synthase activity from denaturation or its zymogen from activation due to endogenous or added protease activity. Evidence is described which supports the proposal that 1,4-beta-glucan synthase is destroyed and possibly converted to 1,3-beta-glucan synthase activity by protease action, and that the latter may then be greatly enhanced by Ca(2+) and polycations.

Journal Article↗

The role of holotrichs in the metabolism of dietary linoleic acid in the rumen.

The uptake and metabolism of linoleic acid by rumen holotrichs (mainly Isotricha prostoma and I. intestinalis) has been examined in in vitro infusion experiments. Maximum absorption and metabolism of [1-14C]linoleate by 2 . 10(6) Isotricha suspended in 100 ml buffer was obtained using an infusion rate of 1.6 mg linoleate/h. After 90 min, 84% of the added substrate was recovered within the cells, mainly as free fatty acid or phospholipid. There was a rapid incorporation of radioactivity into phospholipid, mainly phosphatidylcholine, at the commencement of linoleate infusion but no further incorporation after about 40 min. The presence of bacteria during incubations, in approximately the same Isotricha/bacteria ratio as found in the rumen, reduced the uptake of linoleate and the accumulation of free fatty acid by holotrichs but the incorporation into phospholipid remained similar to that obtained in the absence of bacteria. Very little biohydrogenation of linoleic acid occurred in incubations with holotrichs alone. Bacterial suspensions converted linoleic acid to mainly trans monoene and a small amount of stearic acid, but in incubations containing both bacteria and holotrichs, both stearic acid and trans monoene were major products. Using the latter mixed culture, about 20% of the added [1-14C]linoleic acid was present in holotrich phospholipid of which 62% remained as octadecadienoic acid. The Isotricha population was 3 . 10(3)--2 . 10(4)/ml rumen fluid and it contributed about 23% of the linoleic acid in the rumen of a cow on a hay diet.

Animals↗

[Clinical and social fate of craniocerebral injuries in young adults].

After looking 15 years back, the authors based two detailed observations of young adult cranio-cerebral injured taken amongst a group of 30 others who had been the subject of a medical doctorate thesis. From then on, the authors drew notions of semeiology, concerning the subjects becoming aware of their body before being injured, when waking up from coma and during the phasis of after effects. They mean to suggest to consider the notions of "normal person" and of pre-traumatic mind, of "present person" and of traumatic mind, and of "future person" and of post-traumatic mind. They attempted to write a comparative essay with the cerebral and physical disable of early youth. By way of conclusion, they briefly studied the attitudes of the clinical, familial and social relations and of the medical and legal consequences of these attitudes.

Adaptation, Psychological↗