Search PubMed⌕ Search

Biomedical subjects

M Vial

Publications and source records attributed to M Vial.

At least 73 records · Page 4Linked to original sources

A low rate of perinatal deaths for twin births.

A specific prenatal care program is proposed to prevent preterm deliveries in twin pregnancies, with ultrasound scanning, early work leave and home visits by midwives. A four-year study has been conducted on 197 pregnancies (160 early followed and booked and 37 late referred). It can be shown that early preterm births and very low birth weights are less frequent in the followed group than in published data, as well as in the late referred pregnancies. The total perinatal mortality rate is 25.6 per 1000 total births.

Delivery, Obstetric↗

[Radioautographic localization of neuropeptide receptors in the central nervous system].

The first step of any physiological effect of a neuropeptide (NP) is its recognition by specific receptor sites. The very organization of the central nervous system (CNS) does not permit a precise localization of these binding sites by conventional binding assays. The aim of the present paper is to describe in detail a recently developed in vitro methodology for the localization, visualization and quantitation of specific binding sites for various NP such as TRH, neurotensin and vasoactive intestinal peptide (VIP) in the rat CNS. The combination of this autoradiographic technique with radioimmunological measurements of NP, reveals that the endogenous distribution of THR, for example, in various brain regions, is not correlated with the presence of its binding sites. In vitro autoradiography may also be used to study the neurotransmitter/neuromodulatory role of NP in the CNS. This point will be illustrated by the effect of VIP on serotonin binding sites in both rat suprachiasmatic nucleus and hippocampal formation. Besides, the importance of the endocrine environment of the target tissue for NP action will also be discussed.

Animals↗

In vitro binding of tritiated glucocorticoids directly on unfixed rat brain sections.

We describe a new technique for measuring specific in vitro binding of tritiated adrenal steroids on unfixed cryostat brain sections. The specific binding of [3H]corticosterone represents about 70% of the initial binding. Kinetic studies show that specific binding for [3H]corticosterone reaches equilibrium after 15 min incubation at room temperature. Scatchard analysis of [3H]corticosterone in vitro binding gives a linear plot with an apparent dissociation constant (Kd) and a number of binding sites (Bmax) in the range of 10(-8) M and 100 fmol/mg protein, respectively. [3H]Dexamethasone binding under the same conditions gives a similar Kd and a Bmax of 55 fmol/mg protein. The order of potency for the relative binding affinity for [3H]corticosterone labeled sites is as follows: corticosterone greater than progesterone, dexamethasone, RU 38486 (a "pure" antiglucocorticoid), RU 26988 (a "pure" glucocorticoid), aldosterone greater than estradiol, testosterone. Anatomical studies reveal that sections at the level of the hippocampus bind more [3H]corticosterone and [3H]dexamethasone in vitro than more rostral sections taken at the level of the septum. Adrenalectomy increases the capacity of [3H]corticosterone to bind to these sites and perfusion of the brain to remove transcortin and other blood proteins does not modify [3H]corticosterone binding. We conclude that it is possible to measure in unfixed frozen brain sections glucocorticoid binding sites.

Adrenalectomy↗

In vitro biochemical characterization and autoradiographic distribution of 3H-thyrotropin-releasing hormone binding sites in rat brain sections.

In the present study, we describe the biochemical characteristics and the autoradiographic distribution of thyrotropin-releasing hormone (TRH) receptors in the rat central nervous system (CNS) after in vitro incubation of brain slices with 3H-TRH. Scatchard analysis showed that, in the range of concentrations tested (0.7-35 nM), 3H-TRH bound to a single-class of receptors with a dissociation constant of 6 nM and a number of binding sites of 20 fmol/mg protein. Increasing concentrations of unlabeled TRH produced a dose-dependent inhibition of 3H-TRH binding. The only analogue as potent as TRH to displace 3H-TRH binding was 3-Me-TRH, whereas 1-Me-TRH or TRH-free acid as well as pGlu-His, pGlu-Pro-NH2 or His-Pro-diketopiperazine were ineffective. Neither Luteinizing hormone-releasing hormone (LHRH), neurotensin, somatostatin, D-Ala-Met-enkephalin nor VIP showed any significant affinity for TRH binding sites. Autoradiograms obtained by apposition of LKB 3H-Ultrofilm showed that the highest concentrations of 3H-TRH binding sites were found in the ventral dentate gyrus of the hippocampal formation, the lateral amygdaloid nucleus, the nucleus accumbens, and the thalamic paraventricular nucleus. The biochemical characterization of 3H-TRH binding in brain sections is in good agreement with previous reports on membrane preparations and the autoradiographic localization of the binding sites provides anatomical support for the effects of TRH in the CNS.

Amygdala↗

Brain diurnal levels of adenosine 3',5' cyclic monophosphate in C57 BL/6 and BALB/C mice.

Adenosine 3',5'-cyclic monophosphate (cAMP) was measured in whole brain of two inbred strains of mice (BALB/C and C57 BL/6) submitted to a lighting schedule consisting of 12 hr light (0700-1900) and 12 hr darkness (1900-0700). Different mean levels of cAMP were found in each strain. Furthermore, statistical analysis of diurnal brain cAMP fluctuations showed different nycthemeral rhythms in both strains. BALB/C was mainly characterized by the presence of very significant 0600 and 0800 harmonics and C57 BL/6 by an orthophase around 1700 hr. Because both strains were studied under the same experimental conditions of light, temperature and food availability, these factors cannot account for the observed differences, which were thus tentatively interpreted in terms of genetic regulatory processes.

Animals↗

[Perinatal symptomatology of severe neuromuscular diseases. Apropos of 11 cases].

The neonatal diagnosis of neuro-muscular diseases is difficult. From a series of 11 neonates presenting with such diseases, ante and postnatal semiology has been studied. During pregnancy, hydramnios (7/11) and decreased active movements were the most frequent symptoms. Delivery was often dystotic (7/11). After birth, respiratory distress, lack of motility, hypotonia, and muscle and tendon retraction were the clinical manifestations (10/11). Knowledge of this semiology should facilitate the ante and postnatal screening of affected patients. The diagnosis depends on family history and, overall, on the results of muscle biopsy.

Biopsy↗

Analytical subcellular fractionation of guinea pig peritoneal macrophages: preparation of purified plasma membranes.

A method using sucrose gradient centrifugation is described for the purification of plasma membranes of guinea pig peritoneal macrophages. The subcellular fractions obtained have been submitted to a biochemical and ultrastructural analysis. Two plasma membrane markers, 5'-nucleotidase and alkaline phosphodiesterase I, have been assayed at the same time as markers for other subcellular organelles, DNA (nuclei), succinic dehydrogenase (mitochondria), inosine diphosphatase (endoplasmic reticulum), and acid phosphatase (lysosomes). The exposure of the plasma membranes to a low concentration of digitonin allowed us to obtain their high purification. They are only contaminated by 2-3% of other cell components present in the macrophages homogenate. The representative ultrastructural technique used has confirmed the purity of the plasma membranes isolated.

Animals↗

[Caffey's disease with antenatal onset].

The authors report one case of Caffey's syndrome with antenatal onset. X-ray of the uterus, that was required because of an hydramnios, led to the diagnosis. Ultrasonography showed the fetal anomalies. Data in the literature concerning case reports of Caffey's syndrome with antenatal onset show a moderate incidence of familial cases.

Female↗

[Binding of tritiated corticosterone by brain sections of adrenalectomized rats].

In the present work we describe a new technique which permits us to study the specific binding of tritiated corticosterone in brain sections of adrenalectomized Rats. Under these conditions, the specific binding of the glucocorticoid represents 60 to 70% of the initial binding. The apparent dissociation constant and the number of binding sites, determined by Scatchard analysis, are in the range of 10(-8) M and 100 fmoles/mg of protein respectively.

Adrenalectomy↗

[Clofibrate for the treatment of hyperbilirubinemia in neonates born at term: a double blind controlled study (author's transl)].

A double blind controlled study of the therapeutic effect of clofibrate, an inductor of bilirubin glucuronyl transferase, was performed in neonates born at term and presenting with physiologic jaundice. 47 children were treated with a single oral dose of clofibrate. 46 control children were given corn oil alone. Results show that mean plasma bilirubin levels are significantly lower in the treated group as compared with the control group, from the 16th hour of treatment, if there is no ABO incompatibility. Clofibrate treatment also resulted in a shorter duration of jaundice and a restricted use of phototherapy. No undesirable side-effect was observed.

ABO Blood-Group System↗

[Systematic hip roentgenograms in infants of 4 months of age in the screening for congenital dislocation of the hip (author's transl)].

The authors report the results of a statistical study undertaken for the screening of congenital dislocation of the hip. 961 children born between September 24, 1977 and June 30, 1978 were examined. Congenital dislocation of the hip was diagnosed in 9 (0.9 % of the cases). Out of these, 4 had no clinical sign of dislocatability at birth. The only determination of acetabular angles cannot be relied upon and qualitative criteria such as ilium thickness must be added.

Female↗

[The value of haematological data in the diagnosis of foetomaternal infections (author's transl)].

In a systematic prospective study the levels of mature polymorphonuclear neutrophils (PMN), unsegmented band cells, platelets and fibrinogen were measured during the first 5 days of life. 240 neonates of less than 2 days of age admitted to an intensive care unit were compared with 173 normal infants ("control" group) and 15 infected babies ("infected" group). The changes of PMN with gestational age and during the early days of postnatal life were determined by statistical analysis of the results in the "control" group. The results of the "infected" group demonstrated the change of PMN and unsegmented cells from the day of infection. This data should be used to interpret the levels of PMN, unsegmented band cells and together with the abnormalities in the platelets and plasma fibrinogen levels underlines the value of haemotological tests in the early diagnosis of foetomaternal infections.

Bacterial Infections↗

[Twin pregnancy, indomethacin and neonatal cyanosis (author's transl)].

Two twins born to a mother who had been treated with Indomethacin at the end of pregnancy presented with variable but transitory hypoxemia. Blood Indomethacin determination suggested that this disorder was iatrogenic in origin. Clinical, experimental and pharmacological data in the literature support the hypothesis that this condition was due to pulmonary arterial hypertension.

Adult↗