Biomedical subjects

E Moreau

Publications and source records attributed to E Moreau.

46 records · Page 3Linked to original sources

PubMed1986

[Development of gastric sensitivity to histamine in the rat].

Sensitivity of the developing rat stomach to histamine (HA) was examined on isolated gastric mucosae of rats of various ages from the fetal to adult periods. Spontaneous acid secretion in mu eq/h.cm2 occurred at all the ages studied, at a basal rate of 0.45 +/- 0.07 in fetuses to 0.22 +/- 0.03 (day 5), 0.11 +/- 0.04 (day 10), 0.12 +/- 0.04 (day 12), 0.22 +/- 0.08 (day 16) and 0.33 +/- 0.04 (adults). In the fetal rats as in the adults, marked responses to respectively 10(-5) and 10(-4) M HA were demonstrated. The H2-receptor antagonist cimetidine diminished HA-induced secretion by 66 and 57% in fetuses and adults respectively. Between these two stages (from days 5 to 12), basal secretion and the response to HA dropped significantly. On day 21 of gestation, as well as on the critical days 5 and 12 after parturition, db-cAMP (10(-4) M) caused maximal stimulation of acid secretion. These results indicate that the development of responsiveness to HA in the rat is biphasic. They suggest that after birth, the H2-receptor adenylate cyclase system undergoes major modifications which might lead to the complete lack of responsiveness to HA by day 12.

Aging↗

PubMed1986

[Movement of Na+ and Cl- across the isolated fetal rat stomach].

Unidirectional and net isotopic fluxes of Na+ and Cl- were determined at steady state across isolated stomach of rat fetuses on days 19 and 21. On day 19, when parietal cells are not yet functional, net absorptions of Na+ and Cl- (respectively: 3.8 +/- 1.1 and 5.2 +/- 1.7 mu eq X h-1 X cm-2) were observed. By contrast, active secretion of Cl- (-2.1 +/- 1.8 mu eq X h-1 X cm-2) associated with decreased absorption of Na+ (45%) was noted on day 21, and both Na+ and Cl- net movements accounted for the short-circuit current, as observed on adult gastric mucosa. These results show that Na+ active absorption precedes Cl- secretion in fetal rat at the time of parietal cells differenciation.

Amiloride↗

PubMed1985

Development of gastric histidine decarboxylase in the rat: sensitivity to fasting and secretagogues.

Gastric mucosal histidine decarboxylase (HDase) was measured in fetal rats between days 16 and 21 of gestation, and in newborn rats up to weaning. HDase was not detected in fetal stomach. Its activity developed from day 1 after birth (29 +/- 2 pmol CO2/mg protein/h) and increased up to day 18 when it reached the fed adult level (894 +/- 174 pmol CO2/mg protein/h). Weaning increased HDase activity significantly (weaned versus unweaned rats: 1,664 +/- 150 and 1,036 +/- 170 pmol CO2/mg protein/h; p less than 0.005). Up to day 18, HDase activity was not altered by 16 h to 24 h of fasting. From that day on, HDase became sensitive to both pentagastrin and carbachol. These results indicate that complete functional maturation of histamine-producing cells is only reached at day 18, just before weaning. This developmental pattern may explain the differences observed between fetal and adult regulation of gastric acid secretion.

Animals↗

PubMed1984

A strategy to reveal high-frequency RFLPs along the human X chromosome.

Fifteen human X-chromosome-specific DNA fragments, localized to particular regions of that chromosome, were used to search for restriction fragment length polymorphisms. A screening panel prepared by digesting DNA from only two females and one male with 24 restriction enzymes was sufficient to reveal two-allele polymorphisms among one-third of the probes tested. These polymorphisms, as theoretically anticipated, showed minor allele frequencies above 20%, as a rule. Such high-frequency polymorphism allowed identifying females, from pedigrees segregating three X-linked diseases, who were multiply heterozygous for polymorphic loci spread throughout the X chromosome. In addition, two of the 24 enzymes tested with these X-specific probes, Msp I and Taq I, generate fragment sizes in DNA-blotting experiments that, on average, are significantly larger than expected from nearest neighbor predicted recognition site frequencies.

Alleles↗

PubMed1983

[Education of a hospitalized diabetic population].

During the second semester of 1981, all the diabetic patients who were hospitalized in the department (142 IDD and 75 NIDD) followed an educational program. Approximately half the patients were unable to follow the entire course, owing to visual, motor, intellectual or linguistic impairment. Few patients refused the course (8 cases). Evaluation of the theoretical knowledge at discharge showed poor results in 47% of IDD and 64% of NIDD, with patients in the latter group appearing to be less motivated. Advanced age, unemployment and alcoholism are detrimental factors. In contrast, among 71 IDD who followed only part of the course because of a handicap, 25 nevertheless acquired satisfactory knowledge, justifying an educational program with limited objectives. At follow-up at the outpatient clinic, insulin dependent patients exhibited better metabolic control, self-monitoring and acceptance of their disease; however, the patients who are seen at follow-up examinations are those who have the best theoretical knowledge. A comparative study of hospitalizations shows that admissions for hypoglycemia have decreased between 1978 and 1981, but education is not the only factor. The shortcomings and possible improvements are discussed.

Diabetes Mellitus↗

PubMed1983

Renal glycogen content and hormonal control of enzymes involved in renal glycogen metabolism.

Fetal rat kidney showed glycogen deposition that reached a maximal value of 60 micrograms . mg prot-1 on day 18 and declined there-after. At birth glycogen concentration is reduced (20 micrograms . mg prot-1) but higher than adult one (cortex, 2.2 micrograms . mg prot-1 and medulla, 3.4 micrograms . mg prot-1). From day 17 to the birth, glycogen synthetase and phosphorylase activities increased slowly except for acid glucosidase activity which increased rapidly between day 18 to the birth (3-fold). Corticosteroid deprivation had no effect upon glycogen content but fetal decapitation on day 16 reduced glycogen content in kidney of 19-day-old fetuses.

Adrenal Cortex Hormones↗

PubMed1981

Hormonal control of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activities in the fetal rat kidney.

Triamcinolone (20 microgram per fetus) administered in utero to term rat fetuses (day 21 of gestation) increases the activities of renal G-6-Pase and PEPCK. The absence (or marked decrease) of circulating corticosteroids in fetuses from adrenalectomized, metopirone-treated mothers has, however, no clear effect on the enzyme activities. Therefore, it is doubtful that corticosteroids play a role in the development of G-6-Pase and PEPCK activities during the fetal period of life. In 21-day-old fetuses entirely decapitated on day 18, both enzyme activities are lower than intact fetuses of the same litter (G-6-Pase, -48%; PEPCK, -36%). In partially decapitated fetuses, the activity of G-6-Pase remains at the control level, whereas the PEPCK activity is clearly reduced (-39%). These results strongly suggest that on the last day of gestation the hormone group of parathormone, calcitonin, or thyroxine controls the G-6-Pase activity, whereas the hypothalamo-hypophysis system is implied in the development of PEPCK activity. Parathormone (1 unit per fetus) administered to decapitated fetuses completely restores the G-6-Pase activity. Neither rat growth hormone, synacthene, nor arginine vasopressin has significant effects on the activity of PEPCK in the kidneys of decapitated fetuses. The administration of 0.5 mumole of dibutyryl-cAMP or cyclic adenosine 3':5'-monophosphate (cAMP) to decapitated fetuses completely restores the activity of renal PEPCK, suggesting that the development PEPCK is controlled by cAMP-dependent hormone. The same dose of dibutyryl-cAMP has no effect on the activity of G-6-Pase; cAMP produces a slight but significant increase of this enzyme activity.

Adrenal Cortex Hormones↗

PubMed1979

Development of ammonia and glucose productions from glutamine in foetal rat kidney; effects of metabolic acidosis.

Ammoniagenesis and gluconeogenesis have been studied in foetal rat kidneys during the five last days of gestation by measuring in vitro NH3 and glucose productions from glutamine and by assaying activities of soluble phosphoenolpyruvate carboxykinase(PEPCK) and glucose 6-phosphatase (G6Pase). These studies were carried out in normal (mean blood pH: 7.30) and acidotic (pH: 7.12) foetuses. In normal foetuses, NH3 production by kidney cortex slices remains constant throughout the studied period of development, at a level 10-fold lower than the maternal one. On day 20 of gestation, a low glucose production (20-fold lower than the maternal one) appears for the first time. This may be related to an increase of PEPCK and G6Pase activities which occurs between day 19 and 20. In 20 days old foetuses, NH4Cl induced acidosis stimulates NH3 production but has no effect on PEPCK activity and glucose production. A response of gluconeogenesis to acidosis is observed one day later (day 21).

Acidosis↗

PubMedDate not supplied

Responses of Fasciola hepatica infected sheep to various infection levels.

The response to Fasciola hepatica was studied in sheep infected with 5, 30, 150 metacercariae. The animals were necropsied 12 weeks post-infection (p-i) for counting and measuring flukes. Cellular and humoral responses were detected by peripheral eosinophil count, peripheral blood lymphocyte proliferation with excretory-secretory products (FhESP) and ELISA. All sheep were infected at necropsy except one sheep which was infected with 5 metacercariae. Mean parasitic intensities were 40%, 44% and 27% of the infection dose in sheep infected with 5, 30, 150 metacercariae respectively. FhESP-specific lymphocyte responses of the 3 infected groups were significantly enhanced in weeks 3 and 4 p-i (p < 0.05). The kinetics of the specific humoral response were similar for the 3 infected groups but the antibody level was significantly lower in animals infected with 5 metacercariae than in the 2 other infected groups from week 5 p-i to week 12 p-i (p < 0.05). Peripheral eosinophil count was significantly enhanced (p < 0.05) in infected groups. The numbers of peripheral eosinophils were significantly different between the 3 infected groups in week 3, 4 and 6 p-i and were related to infection level. These results confirm that sheep are highly susceptible to F. hepatica infection, even when infection pressure is very low. Peripheral eosinophilia was dependent of the infection level. The immune response was similar in sheep infected with various numbers of flukes.

Animals↗

PubMedDate not supplied

Lack of humoral and cellular responses against glutathione S-transferases in Fasciola hepatica experimentally infected sheep.

Anti-Fasciola hepatica excretory-secretory products (FhESP) and anti-glutathione S-transferase (GST) immune response were studied in sheep infected with 250 F. hepatica metacercariae. In FhESP, 29 proteins with molecular masses (m) of 10-200 kDa were identified by SDS-PAGE. GST m were 26.7 and 27.2 kDa. The anti-FhESP humoral response was precocious and increased throughout the infection. FhESP contains several immunoreactive antigens but no anti-GST antibodies were detected either by ELISA or western blotting. The anti-FhESP cellular response increased precociously and fell after the second week of infection but no cellular response against GST was observed.

Animals↗