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D Lenys

Publications and source records attributed to D Lenys.

At least 37 records · Page 2Linked to original sources
PubMed1987

[Contribution of immunocytochemistry to the study of the development of neuroglandular peptidergic systems in the human fetal hypothalamus].

Immunohistochemistry makes possible the in situ detection of neuropeptides in the cell bodies were they are synthesized, in the fibers that carry them, and in endings. Immunohistochemistry appears necessary to identify and map peptidergic neurons and to study their ontogeny. From 1975, we have carried the immunohistochemical study of several hypothalamic neuronal populations in the human fetus: LH-RH (1976), somatostatin (1977), pro-opiocortin (1978), vasopressin and oxytocin (1979), corticoliberin (1982), somatocrinin (1983), and hypothalamic neurons containing an unidentified peptide (1984). Comparative ontogenetical studies have also been performed in rats.

Animals↗
PubMed1985

[Circulating and basophil-fixed specific IgE in human alveolar echinococcosis].

Biological parameters of immediate type hypersensitivity were assessed in 19 patients with alveolar echinococcosis. Serum total IgE concentrations were higher than normal values in 12 patients, and parasite-specific IgE were present in 9 patients. A significant relationship was observed between these two parameters. Evolution of specific IgE during a 1-year period appeared to correlate with surgical removal of parasitic material; it did not correlate with the clinical evolution in patients treated with mebendazole. Specific basophil fixed-IgE were demonstrated using both a basophil degranulation test and a histamine release test in the 19 patients under study, including serologically negative and circulating specific IgE-negative patients.

Basophils↗
PubMed1980

[In vitro effects of glycolytic substrates and some nucleotides (ATP, ADP, AMP, cyclic AMP) on the motility of spermatozoids of human sperm, asthenospermic or normal].

The effects of several drugs upon normal and asthenospermic human sperms were tested: cyclic AMP significantly and constantly increased the rate of motile spermatozoa in most samples having an initial motility rate between 20 and 60%. ATP kept up high the motility rate, particularly in sperm displaying the highest initial motility. Other drugs (glycolytic substrates, pyruvate, ADP, AMP, caffeine had inconstant effects upon a few sperms. None drug was efficient upon sperms with initial motility rate lower than 20%; this was probably due to important lesions of the locomotor apparatus of the spermatozoa, as shown by electron microscopy investigations.

Adenine Nucleotides↗
PubMed1979

Infundibular neurons of the human hypothalamus simultaneously reactive with antisera against endorphins, ACTH, MSH and beta-LPH.

In man, discrete neurons of the infundibular (arcuate) nucleus contain compounds that can be stained with anti-endorphin (alpha and beta), anti-ACTH, anti-MSH (alpha and beta) and anti-beta-LPH immune sera (I.S.). In the fetus, certain neurons stain with anti-beta-endorphin or anti((17--39)ACTH starting from the 11th week of fetal life. At the ultrastructural level, these neurons contain elementary granules that are immunoreactive with anti-beta-endorphin. In the adult, neurons immunoreactive with anti-beta-endorphin are found in the infundibular nucleus. Their axonal fibers terminate around blood vessels in the neurovascular zone and in the pituitary stalk, or establish contacts with non-immunoreactive perikarya of the infundibular nucleus. These neurons can be stained with anti(17--39)ACTH and anti-beta-endorphin I.S. The most reactive are also stained moderately with anti-alpha-MSH, anti-beta-MSH, anti-beta-LPH, anti-alpha-endorphin, or anti(1--24)ACTH I.S. These results indicate that, in man, compound(s) identical with or immunologically related to endorphins, beta-LPH, ACTH and MSH are secreted by certain hypothalamic neurons. These agents probably originate from a common precursor molecula similar to the so-called pro-opiocortin.

Adrenocorticotropic Hormone↗
PubMed1979

Neurons of the rat hypothalamus reactive with antisera against endorphins, ACTH, MSH and beta-LPH.

In rat brains intraventricularly injected with colchicine, the same discrete neurons of the arcuate and ventromedial nuclei can be stained with antisera against alpha- and beta-endorphins, (1-24)ACTH, (17-39)ACTH, alpha- and beta-MSH, and beta-LPH, as demonstrated by comparative studies in consecutive serial sections. These neurons are strongly reactive with anti-(17-39)ACTH, anti-beta-endorphin, anti-alpha-MSH and anti-beta-MSH, and more faintly stained with anti-alpha-endorphin, anti-beta-LPH and anti-(1-24)ACTH. Exceptionally, neurons reactive with anti-(17-39)ACTH and anti-beta-endorphin are poorly stained or completely negative with anti-alpha-MSH and anti-beta-MSH. Immunoreactive fibers end in the lateral median eminence and in the arcuate nucleus proper, or form ascending pathways along the third ventricle. Comparative studies with other antisera or with the Falck and Hillarp technique show that these neurons differ from the elements producing LH-RH, somatostatin, neurophysin, oxytocin, vasopressin and dopamine. These results suggest that the same neurons of the rat hypothalamus synthesize several neuropeptides identical with or immunologically related to endorphins, ACTH, alpha-MSH and beta-LPH, probably arising from a common precursor molecule similar to that found in the corticotropic cells of the pituitary. These neuropeptides of a common cellular and molecular origin might be involved in basic processes of the central nervous system as neurotramsmitters or neuromodulators.

Adrenocorticotropic Hormone↗
PubMed1979

Comparative study of the neuronal populations containing beta-endorphin, corticotropin and dopamine in the arcuate nucleus of the rat hypothalamus.

Neurons simultaneously immunoreactive with anti-beta-endorphin and anti-(17-39) corticotropin (anti(17-39) ACTH) have been detected in the arcuate and ventromedial nuclei of the hypothalamus of colchicine-treated rats. These neurons are different from those fluorescent with the Falck and Hillarp technique. These results show that in the arcuate nucleus, immunoreactive ACTH and beta-endorphine are stored in the same neurons which are different from dopamine-containing neurons.

Adrenocorticotropic Hormone↗
PubMed1979

[Immunocytologic analysis, in rat hypothalamus, of neurons producing peptides related to endorphin, ACTH, MSH and beta-LPH. Comparison with other peptidergic and monoaminergic neurons].

In rat hypothalamus intraventricularly injected with colchicine, the same neurons of the ventral region are stained with I.S. against alpha and beta-endorphin, (1-24) and (17-39) ACTH, alpha and beta-MSH, and beta-LPH. They are distinct from those producing LH-RH, somatostatin, neurophysin, and dopamine. These results suggest that the same neurons elaborate peptides identical with or immunologically related to endorphins, ACTH, alpha-MSH and beta-LPH, probably issued from a common precursor.

Adrenocorticotropic Hormone↗
PubMed1979

[Immunocytochemical study of the maturation of the hypothalamo-neuro-hypophysial axes in the human fetus (author's transl)].

1. The development of the hypothalamo-neurohypophysial system was studied using immunocytochemistry with various antisera : anti-neurophysin, anti-oxytocin, anti-vasopressin, anti-vasotocin and anti-somatostatin. 2. Immunocytochemical investigation shows that anti-vasopressin and anti-vasotocin sera react with both vasopressin and vasotocin, whereas the anti-oxytocin serum specifically reveals the oxytocin-containing structures (Fig. 1g, h, i). 3. Perikarya stained with anti-neurophysin, anti-vasopressin and anti-vasotocin sera can be seen from the 11th week of fetal life (Fig. 1a) first in the supra-optic nucleus (SON), then in the para-ventricular nucleus (PVN). Their axons reach the neural lobe as early as the 11th week (Fig. 1b, c). 4. Oxytocin-containing perikarya appear simultaneously in the PVN (Fig. 1e) and SON during the 13th week. 5. From the 16th week, neurons stained with the anti-somatostatin serum can be seen among the neurophysin-positive cell-bodies of the SON and PVN. 6. The various populations of magnocellular neurons show a significant increase in number, especially up to the 19th week, and an increase in their hormonal content up to birth.

Animals↗
PubMed1978

[Antigenic determinants of beta-LPH, beta-MSH, alpha-endorphin, ACTH and alpha-MSH revealed by anti-beta-endorphin in neurons of the human infundibular nucleus].

Comparison of adjacent serial sections of the tubero-infundibular region of Human adult hypothalamus demonstrates that the same perikarya, axons and terminals are stained both with anti-beta-endorphin and anti 17-39 ACTH antisera. The most immunoreactive of these neurons are also revealed with anti alpha-endorphin, anti alpha and beta-MSH, anti-1-24 ACTH and anti beta-LPH. These results suggest that neurons of the infundibular nucleus can store and probably secrete peptide similar to propiocortin or fragment(s) of this molecule.

Adrenocorticotropic Hormone↗
PubMed1978

[Description of neurons immunoreactive to anti-beta-endorphin immune serum present in the infundibular nucleus in man].

Neurons containing peptide (s) immunologically related to beta-endorphin have been detected by immunochemistry in human adult and fetal hypothalami. Their perikarya are located in the infundibular nucleus. Some fibres terminate close to vessels in the median eminence, others form pericellular baskets around perikarya of non-immunoreactive neurons of the infundibular nucleus. These results suggest that the central nervous system elaborates beta-endorphin or immunologically related peptides.

Adult↗
PubMed1977

[Somatostatin-containing fibers and neurophysin-containing fibers in the median eminence of the fox, as seen with a double staining cytoimmunoenzyme technique].

In the external layer of the median eminence of the fox, the somatostatin-containing fibers and neurophysin-containing fibers of the hypothalamo-infundibular tract are located in distinct areas. In the neural lobe, somatostatin-positive areas are simultaneously neurophysin-positive. Outside the SON and PVN, some somatostatin-positive and neurophysin-negative perikarya are scattered close to the third ventricle. These facts suggest the existence of two somatostatin systems: a hypothalamo-infundibular (neurophysin-negative) one and a hypothalamo-neurohypophyseal (neurophysin-positive) one.

Animals↗
PubMed1977

[Immunocytological study of the gonadotrophic and thyrotrophic cells of the rat adenohypophysis].

On paraffin or semi-thin sections various anti-LH or anti-TSH sera stain indifferently all the thyrotrophs and the gonadotrophs. Inversely anti-beta-TSH, anti-beta-LH or anti-beta-FSH purified sera permit the discrimination of these two cell populations. The constancy of fixation of the anti-beta-LH and anti-beta-FSH sera on all the gonadotrophs gives evidence of their ability to produce both FSH and LH. However in a few female rats the central gonadotrophs are stained more weakly by anti-beta-FSH serum than by anti-beta-LH serum. The purification of the antisera by adjunction of hormonal antigens (alpha subunits or heterologous hormone) does not enable, with the PAP technique on thin sections, a selective staining of the secretory granules of the thyrotrophs or of the gonadotrophs.

Animals↗
PubMed1976

[Immunocytochemical study using semi-thin sections of the phenomena of early differentiation in several cell populations of the human fetal adenohypophysis].

Immunocytological investigations have been performed on semi-thin sections of human fetal pituitaries ranging in fetal age from 6 to 26 weeks. Corticotrophs can be revealed by anti-ACTH (1-24), anti-ACTH (17-39) and anti-beta MSH but not by anti-alpha MSH immunesera from the 8th week. Somatotrophs are revealed with anti-human STH from 9th week. Differentiating cells containing only alpha subunits of glycoproteic hormones are present from 8th to 12th week. At 13th week beta subunits of TSH can be revealed immunocytologically in thyreotrophs. Beta subunits of LH or FSH can be detected in same gonadotrophic cells only from 15th week.

Adrenocorticotropic Hormone↗
PubMed1975

[Effect of various inhibitors on oxidative activity and ultrastructure of rat liver mitochondria].

Parallel studies concerning the influence of some inhibitors on electron transfer, and ultrastructural aspects of rat liver mitochondria led to the conclusion that metabolic activity and mitochondrial ultrastructure are closely linked ; when mitochondria oxidize succinate, their configuration change from the "condensed" to the "orthodox" state ; this change does not occur if the oxidation is inhibited.

Animals↗