Search PubMed⌕ Search

Biomedical subjects

D Gauthier

Publications and source records attributed to D Gauthier.

54 records · Page 3Linked to original sources

FSH and LH variations in beef cows during the postpartum period.

To study the plasma gonadotrophin profiles of 9 cows after parturition, blood samples were obtained every 20 min for 12 hrs on three occasions between 5 and 50 days postpartum and analysed by RIA techniques. The time of the first ovulation, as judged by plasma progesterone levels, varied from 30 to more than 60 days postpartum. Variations in mean levels of FSH and LH were not significantly correlated with the postpartum interval. However, the mean levels of plasma FSH and number of LH pulses were lower in females which had not ovulated than in those which had. The cows could be classified into four groups: group 1 with less than 4 LH pulses in 12 hrs and a mean plasma FSH level less than 138 ng/ml; group 2 with more than 4 LH pulses in 12 hrs and varying plasma FSH levels; group 3 with less than 4 LH pulses in 12 hrs and a mean plasma FSH level greater than 138 ng/ml; group 4 which had ovulated. This classification indicated that the LH and FSH levels progressed significantly (2.46 to 3.56 ng/ml, P less than 0.05; 120 to 159 ng/ml, P less than 0.01, respectively) from groups 1 to 3, and that they decreased in the females which had ovulated (group 4). Since the time of the first ovulation after parturition varied, it was not possible to demonstrate any relationship between that interval and the mean plasma gonadotrophin profiles. However, when ovulation was considered as time zero there was a clear increase in plasma gonadotrophin before ovulation.

Animals↗

The influence of nutritional levels and shade structure on testicular growth and hourly variations of plasma LH and testosterone levels in young Creole bulls in a tropical environment.

Twelve Creole bulls 13.3 months of age were divided into three groups according to live weight. The first group received a low nutritional level and was housed in a shaded stable; the second group received a high nutritional level and was housed in the same stable as the first group; the third group received the same ration as the second group but was exposed to solar radiation. Live weight and testicular diameter were recorded fortnightly. After 65 days, the blood of the bulls was sampled every 20 min for 12 h. Plasma LH and testosterone were quantified by radioimmunoassay. There was no significant influence of solar radiation on the testicular growth or the hormonal levels. Underfeeding decreased testicular growth and the average plasma LH and testosterone levels. However, this action was effective only in decreasing the number of hormonal pulses per day (0.63 vs 2.55 LH pulses per day and 0.75 vs 2.50 testosterone pulses per day); it did not change the basal hormone levels. It is suggested that this decrease in LH pulsatility might be responsible for the slow testicular growth in the underfed bulls.

Animals↗

Angiotensin converting enzyme activity and evolution of pulmonary vascular disease in rats with monocrotaline pulmonary hypertension.

We have investigated the role of angiotensin converting enzyme (ACE) in the development of pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular disease in rats given a single subcutaneous injection of the pyrrolizidine alkaloid monocrotaline. Thirty-six young female Wistar rats were divided into a test group of 27 animals and a control group of nine animals. Each test rat was given a single subcutaneous injection of monocrotaline (60 mg/kg body weight). On the first, third, fifth, seventh, tenth, twelfth, fourteenth, seventeenth, and twenty-second days after the injection of monocrotaline the mean right ventricular systolic blood pressure was measured in one control and three test rats. The animals were then killed and we measured the specific activity of ACE in serum and lung homogenate. We also evaluated muscularisation of pulmonary arterioles, medial hypertrophy of muscular pulmonary arteries, and right ventricular hypertrophy. The sequence of changes was as follows: muscularisation of pulmonary arterioles and medial hypertrophy of muscular pulmonary arteries were apparent seven days after administration of monocrotaline; pulmonary hypertension and reduced lung ACE activity occurred after 10 days; right ventricular hypertrophy was detected after 12 days. Serum ACE activity was unchanged. It is concluded that the reduction in lung ACE activity is a result rather than a cause of the pulmonary hypertension. This reduction in lung ACE activity may be a protective mechanism designed to limit the elevation of the pulmonary arterial pressure.

Animals↗

Lung angiotensin converting enzyme activity in rats with pulmonary hypertension.

We have studied serum and lung tissue angiotensin converting enzyme (ACE) activity in female Wistar rats with pulmonary hypertension induced by two different methods. Chronic pulmonary hypertension was produced in one group of 10 rats (CH) by confinement in a hypobaric chamber (380 mmHg) for three weeks, and in another group fo 10 rats (M) by a single subcutaneous injection of monocrotaline (60 mg/kg body weight). In these two groups of tests rats and in 20 untreated controls (C), we evaluated right ventricular mean systolic blood pressure (Prvs mmHg), right ventricular hypertrophy, and serum ACE (n mol/ml/min). In lung tissue homogenate, we measured the specific activity of ACE (n mol/mg protein/min), alkaline phosphatase (AP) (IU/mg protein) and lactic dehydrogenase (LDH) (IU/mg protein). The Prvs in groups, C, CH, and M was 25 +/- 7 SD, 41 +/- 7, and 51 +/- 5, respectively. The ratio of right ot left ventricular weight (RV/(LV + S)%) in groups, C, CH, and M was 29 +/- 4, 52 +/- 5, and 56 +/- 7, respectively. The lung tissue ACE in groups C, CH, and M was 85 +/- 11, 65 +/- 20, and 22 +/- 5, respectively. In groups CH, and M the Prvs and RV/(LV + S)% were significantly elevated above control values while lung ACE was significant decreased (p less than 0.05). There was a significant inverse relationship between lung ACE on one hand, and Prvs (r = - 0.73) and RV/(LV + S)% (r = - 0.71) on the other hand. Serum ACE and lung AP were unchanged. In group M there was a slight but significant reduction in lung LDH. Chronic pulmonary hypertension, irrespective of its method of production, is associated with decreased lung ACE. The reduction in lung ACE is inversely proportional to the severity of pulmonary hypertension and right ventricular hypertrophy.

Alkaline Phosphatase↗

[Seasonal variations in creole heifer cyclicity: effect of growth, age and emotivity].

The ovarian and estrous activities in creole heifers have been studied in Guadeloupe in a tropical environment. We carried out two experiments. In the first one, all the heifers from the research station's herd were blood-sampled twice every 2 months at a 10-day interval to determine their ovarian activity. The observations were ranked in order of ascending live weight, and the percentage of heifers showing ovarian activity was calculated for consecutive 10-kg increments in live weight from 115 to 275 kg. The percentage showing ovarian activity (Y) was subjected to probit transformation and related to live weight (X); probit Y = 12.4 log10 X - 23.7. The equation for observations ranked in order of ascending age and the percentage of heifers showing ovarian activity calculated for age increments over 2 consecutive months was: probit Y = 7.06 log10 X - 3.9. Furthermore, the percentage of cyclic heifers in the herd varied from 40 p. 100 in September 1979 to 0 p. 100 in July 1980 and then to 30 p. 100 in September 1980. The percentage of cyclic heifers at a given period of observation was highly correlated with the mean daily increase in body weight (r = 0.86). In the second experiment, 12 heifers with a high feed level were blood-sampled weekly and checked for estrous daily with an androgenized female with a chin ball mating harness. The mean duration of a "normal cycle" (interval between two estruses: more than 15 but less than 31 days) was 21 days. There was no variation of ovarian activity with the month of the year, but the incidence of silent ovulation was high (23.7 p. 100). The seasonal variation of this percentage is shown. Female emotivity was also an important factor: emotional heifers had a higher percentage of silent ovulations than unemotional heifers (27 vs 17 p. 100) and a smaller mean daily gain (180 vs 280 g).

Age Factors↗

[Influence of undernutrition in the lactating cow on ovulation induction by serum gonadotropins (PMSG) during the post-partum period].

Two experiments were carried out to assess the influence of undernutrition on postpartum ovulation in nursing Charolais cows after PMSG injection. In each experiment, the nursing cows were divided into 2 groups: one fed at a low nutritional level and the other at a normal nutritional level. In the first experiment, 19 animals were injected on post-partum days 15 and 30 with 600 IU of PMSG; in the second experiment, 34 received the same injection on post-partum day 54 after 9 days of priming with a Norgestomet implant. On post-partum day 15, only one cow in each group ovulated. At post-partum day 30, 1 out of 8 cows at the low nutritional plane ovulated vs 5 out of 9 at the normal nutritional plane (P less than 0.05). Likewise, on post-partum day 54, 5 out of 14 cows at the low nutritional plane ovulated vs 17 out of 17 at the normal nutritional level (P less than 0.05). Therefore, there is a time during the post-partum period when the nursing cow ovary does not respond to PMSG by ovulation. The length of this time is increased by undernutrition.

Animals↗

Expanded linkage map of Vibrio cholerae.

An expanded linkage map of the Vibrio cholerae classical strain 162 chromosome has been prepared using a variety of new auxotrophic mutants. The chromosome consists of a single, linear linkage group. The map consists of 17 markers, which have been ordered; 20 mutational sites, which are tentatively ordered; five markers (ura-1, ser-2, mal-1, man-1, suc-1), which are linked but unordered; and three mutations (aro-2, cys-2 and cys-6) which showed little or no linkage. A proposal is made to standardize genetic nomenclature in V. cholerae genetic studies.

Chromosome Mapping↗

Use of recombinant human erythropoietin (EPO-alfa) in a mother alloimmunized to the Js(b) antigen.

Erythropoietin (EPO) is a glycoprotein hormone and the principal regulator of erythropoiesis in the fetus, newborn, and adult. EPO-alfa is erythropoietin manufactured by recombinant human DNA technology (rhEPO). After counseling, a pregnant woman with anti-Js(b) in her serum was started on rhEPO (600 U/Kg, biweekly) to prevent anemia secondary to serial donations of her blood for fetal transfusions. After a total of 25 rhEPO infusions and autologous donation of 8 units of whole blood, maternal hemoglobin prior to the elective cesarean section at 37 weeks was 11.3 gm/dL. Serum EPO concentration was determined in paired maternal and fetal blood samples, before ultrasound guided intravascular transfusions, in this alloimmunized Js(b)-negative and another Rh(D) alloimmunized pregnancy to determine possible correlations between maternal and fetal serum EPO. rhEPO prevented anemia in a patient who donated 8 units of blood from 18-37 weeks of pregnancy without inducing adverse biological effects such as hypertension or thrombotic complications in the placenta. Data presented in this study suggest that EPO does not cross the human placenta.

Adult↗

Acupressure as an adjunct to a pulmonary rehabilitation program.

BACKGROUND: Acupressure is a therapy in which gentle pressure is applied with fingers at specific acupoints on the body. It is reported to relieve pain and have other beneficial effects. This study was designed to ascertain the value of self-administered acupressure as an adjunct to a pulmonary rehabilitation program (PRP) for relief of dyspnea and other symptoms in patients with chronic obstructive pulmonary disease (COPD). METHODS: A single-blind pretest-posttest, cross-over design was used. Thirty-one new patients beginning a 12-week PRP at two private hospitals were randomly assigned to one of two groups. Patients in group 1 were taught acupressure and practiced it daily at home for 6 weeks, then sham acupressure for the following 6 weeks. In group 2, the order of acupressure and sham acupressure was reversed. During weeks 1, 6, and 12, patient dyspnea, other symptoms associated with COPD, activity tolerance, lung function, and functional exercise capacity were assessed. RESULTS: Real acupressure was more effective than sham acupressure for reducing dyspnea as measured by a visual analog scale (P = .009, one-tailed), and was minimally effective for relieving decathexis (P = .044, one-tailed). Sham acupressure seemed to be more effective than real acupressure for reducing peripheral sensory symptoms (P = .002, two-tailed), but the presence of these symptoms may also be an indication that the acupressure is affecting the body. CONCLUSIONS: Acupressure seems to be useful to patients with COPD as an adjunct to a PRP in reducing dyspnea. Some persons who are not initially familiar with traditional Chinese medicine can learn and will accept self-administered acupressure as part of their self-care.

Acupressure↗

Ultrasonographic prenatal diagnosis of the 13q-syndrome.

A case is presented in which ultrasonographic examination led to the prenatal detection of a ring 13 chromosome in a fetus. At 18 weeks' gestation, the fetus presented with holoprosencephaly, an abnormal configuration of the lower extremities, and an atrial septal defect. Although the amount of amniotic fluid was normal, limb movements were never observed throughout pregnancy. The lower extremities were always flexed at the knee and talipes equinovarus was present. Hydrocephaly became apparent during the 2nd trimester. The ultrasonographic findings were confirmed by postpartum autopsy and X-ray examination. The ring chromosome was identified through amniocentesis and later verified in postpartum tissue.

Adolescent↗

[Taxonomic study of free nitrogen-fixing bacteria isolated from the endorhizosphere of rice].

Twenty strains of free-living N2-fixing bacteria, isolated from the endorhizosphere of rice in rice soils of Senegal, were studied on the basis of 259 morphological, physiological, biochemical and nutritional characters. Half of them were Gram-negative small rods with polar flagella and showing a strictly respiratory metabolism; they were characteristic of the genus Pseudomonas. A first group of 6 strains was related to the P. cepacia-P. marginata group characterized by lophotrichous flagella; they accumulated polyhydroxybutyrate, assimilated arginine and betaine, grew at 41 degrees C and showed a wide nutritional spectrum with DNA GC% of 67-68. The second group of 4 strains was related to the P. lemoignei group because of (a) its monotrichous flagella, (b) poly-beta-hydroxybutyrate accumulation, (c) failure to assimilate arginine and betaine and to grow at 41 degrees C, (d) lack of arginine dihydrolase and (e) its narrow nutritional spectrum. DNA GC% was 65. These 4 strains were also denitrifying bacteria. Six strains were related to the genus Alcaligenes because of their strictly respiratory metabolism and their peritrichous flagella; their nutritional spectrum was variable and one of them was a denitrifier. DNA GC% was 68. One strain was related to Aeromonas hydrophila of the Vibrionaceae family; it consisted of Gram-negative and oxidase-positive small rods with monotrichous polar flagella and respiratory and fermentative metabolism without gas evolution. This strain essentially assimilated sugars and its DNA GC% was 63. Another strain was a Gram- and oxidase-negative small rod with peritrichous flagella and respiratory and fermentative metabolism with gas evolution. Sugars, organic acids and amino acids were assimilated. The DNA GC% was 53. This strain was related to Enterobacter cloacae of the Enterobacteriaceae family, but it showed the additional faculty of denitrification. The last two strains studied were spirilla with amphitrichous flagella characteristic of the genus Aquaspirillum. They showed a strictly respiratory metabolism and a DNA CG% of 60-64. This study allowed us to show the N2-fixing capacity of species of Pseudomonas, Alcaligenes and Aeromonas which had been devoid of N2-fixing bacteria until this time. All strains studied were microaerophilic for N2 fixation.

Bacteria↗

[Distribution of heterotrophic aerobic microflora and specially denitrifying and free-living nitrogen-fixing bacteria in the rhizosphere of rice (author's transl)].

The distribution of heterotrophic aerobic bacteria, actinomycetes and fungi was estimated in three samples (rhizospherical soil (SR), rhizoplane (R) and endorhizosphere (ER)) obtained from one rice seedling which had grown in pot during four mounths in a Casamance grey soil. The number of microbial populations were about the same from one sample to another: 1.1 to 2 X 10(8) bacteria, 3.3 to 8.6 X 10(6) actinomycetes and 0.2 to 8.9 X 10(4) fungi per gram of dry soil (SR) or dry roots (R and ER). The denitrifying and free-living nitrogen fixing bacteria were numerous (10(7) bacteria/g) but lower for ER where the number of actinomycetes remained high. Thirty-six bacterial strains have been isolated from every sample with the use of a grid of isolation. The Gram-negative bacteria were dominant in SR and R where they represented respectively 70 and 94% of total count. The major groups were non-sporulated Gram-variable rods (SR) and Alcaligenes-like bacteria (ER). The pseudomonads represented quite 15% of total count in the three samples. On the other hand, the frequency of endospore-forming Gram-positive bacteria was high only in R where the Bacillus group was estimated to 45% of total count. Only 5 free-living nitrogen-fixing bacterial strains had shown a denitrifying ability.

Aerobiosis↗