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Biomedical subjects

A Dupont

Publications and source records attributed to A Dupont.

At least 235 records · Page 13Linked to original sources
PubMed1976

Isolation and structure of somatostatin from porcine hypothalami.

The isolation and structure of somatostatin (GH-RIH) from pig hypothalami are described. This hormone was purified by preparative gel filtration, solvent extraction, countercurrent distribution in two solvent systems, ion-exchange and partition chromatography, and analytical gel filtration. The somatostatin activity was followed by in vitro bioassays and a radioimmunoassay. The isolated product was homogeneous chromatographically and had biological and immunological properties similar to synthetic somatostatin corresponding to the ovine hormone. The primary structure of porcine somatostatin was shown to be H-Ala-Gly-cyclo-(Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys)-OH. Other immunologically and biologically active form(s) of somatostatin were also detected.

Amino Acid Sequence↗
PubMed1976

Effect of thyroxine on the inactivation of thyrotrophin-releasing hormone by rat and human plasma.

The inactivation of synthetic [3H]thyrotrophin-releasing hormone (TRH) by plasma was studied in rats treated with propylthiouracil (PTU) alone or with PTU and thyroxine. 48 h after the onset of treatment with thyroxine, the capacity of rat plasma to inactivate [3H]TRH was significantly increased. The percentage of deamidation of TRH to TRH-free acid was increased 2-fold after 4 days of administration of thyroid hormone. The inactivation of TRH by plasma from hypothyroid patients was compared to that obtained from hyperthyroid patients. Extraction of human plasma incubated with [3H]TRH, followed by thin-layer electrophoresis, showed that transformation of [3H[TRH into TRH-free acid was 44% higher in plasma from hyperthyroid than from hypothyroid patients (P less than 0-05). These data suggest that the inactivation process of TRH by blood proteins could be an important factor in the regulation of the hypothalamo-hypophyseal-thyroid axis in rat and man.

Animals↗
PubMed1976

Psychiatric treatment in a delimited population-with particular reference to outpatients. A demographic study.

The present investigation analyses the psychiatric service available to and utilized by a population in a geogrphically delimited area, namely the Randers area with a population of 108.928. During the period 1970-74, the average yearly rate of patients admitted to the three psychiatric institutions covering this area was per 1,000: 7.9 males and 9.1 females. During 1970-71, 1.2 males and 1.8 females per 1,000 were treated as outpatients in a psychiatric clinic affiliated to a psychiatric hospital, and a psychiatric outpatient clinic in a general hospital discharged 4.1 males and 7.7 females per 1,000. It seems probable that despite outpatient treatment the number of admissions increases slightly rather than decreases, and consequently, outpatient treatment cannot replace psychiatric admission.

Adolescent↗
PubMed1976

Ocular pathology in the elfin face syndrome (the Fanconi-Schlesinger type of idiopathic hypercalcaemia of infancy). Histochemical and ultrastructural study of a case.

The pathology, particularly the ocular pathology, is described in a 42-year-old mildly retarded man with a history of vomiting in infancy. He had an elfin-like face. He died having a pancreatic carcinoma. At autopsy, a supravalvular aortic stenosis and a hypoplastic aorta found clinically were confirmed. Stainings for calcium were positive in the aortic wall, the kidneys, the adrenals and the spleen. In the eyes, calcium was found in the corneal epithelium and endothelium, in corneal keratocytes and stroma, in conjunctival epithelium and in the sclera. Electron microscopy of the eyes revealed that calcium was deposited as hydroxyapatite intracellularly in aggregations of needle-like crystals and extracellularly as spherules morphologically different from the intracellular deposits. Although the serum values of calcium in this patient were normal during his adult life, the histopathological examination indicates an earlier period of raised serum calcium. We find it probable that he had idiopathic hypercalcaemia in infancy, thereby connecting this infantile condition with the elfin face and supravalvular aortic stenosis. In similar cases, the use of the above-mentioned technique is recommended for revealing abnormal calcium storage post-mortem and in vivo (by conjunctival biopsy) in order to substantiate the diagnosis of hypercalcaemia.

Adult↗
PubMed1976

Re-examination of porcine and bovine hypothalamic fractions for additional luteinizing hormone and follicle stimulating hormone-releasing activities.

More than 150 hypothalamic fractions were reassayed for luteinizing hormone-releasing hormone (LHRH) and follicle stimulating hormone-releasing hormone (FSHRH) activities in search for LHRH and FSHRH which differ from the decapeptide (pyro)Glu-His-Trp-Ser-Try-Gly-Leu-Arg-Pro-Gly-NH2 (I). Among the porcine fractions tested were those obtained: 1) from the isolation of thyrotropin-releasing hormone; 2) from two isolation procedures for LHRH; and 3) from methanolic and aqueous 2N acetic acid extracts which were subjected to Biogel P-2 filtration and partition chromatography. Some bovine hypothalamic fractions were also tested. Both in vivo and in vitro assays were used for measuring LHRH and FSHRH activities. The values obtained were in each case compared with those resulting from the administration of pure natural or synthetic LHRH decapeptide I. A radioimmunoassay for LHRH (I) was also utilized for some fractions. In all the purification steps the location of LHRH and FSHRH activity, as determined by in vivo assays, corresponded to that of the decapeptide I. Purification of hypothalamic extracts on Biogel P-2 and by partition chromatography separated a fraction from the decapeptide I, which released more FSH than LH in vitro from the pituitaries of immature female rats. However, this material was inactive in vivo and in other in vitro systems, so that its significance is obscure. The results suggest that if material with LHRH and FSHRH activity other than the decapeptide I is present in acid extracts of porcine hypothalami, then its FSHRH and LHRH activity would be a minor part of the total LHRH/FSHRH activity in the extracts. (Pyro)-Glu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2 appears to account for most of all of the LHRH and FSHRH activity found.

Animals↗
PubMed1976

[Case report of giant calcified pituitary adenoma].

The exceptional nature of compact, extensive calcifications in a giant pituitary adenoma points to the possibility of immunological, histological and chemical mechanisms in the calcification process.

Adenoma, Chromophobe↗
PubMed1975

Somatostatin: abundance of immunoreactive hormone in rat stomach and pancreas.

Growth hormone release-inhibiting hormone (somatostatin), a hypothalamic peptide that inhibits the release of growth hormone and also the secretion of insulin glucagon, and gastrin, was found in the rat stomach and pancreas in a concentration similar to that in the hypothalamus, as measured by radioimmunoassay. Somatostatin was also found in the duodenum and jejunum, but in a smaller concentration. Gel filtration of the extracts of the pancreas and stomach on Sephadex G-25 yielded two immunoreactive peaks, one corresponding in each case to the somatostatin tetradecapeptide. The hormone was not detected in other viscera or the ovaries. The results imply that somatostatin may be synthesized in the pancreas and the stomach in addition to the brain, and may be involved in local regulatory mechanisms for pancreatic and gastric secretion as well as secretion of growth hormone.

Animals↗
PubMed1975

Ultrastructural study of the uptake of peroxidase by the rat median eminence.

An active role of the ependymal cells (tanycytes) of the median eminence in the transport of hypothalamic hormones has been recently suggested. In order to investigate the fate of material present in the cerebrospinal fluid, a protein tracer, horse-radish peroxidase (HRP) was injected into the left lateral ventricle of rats. Two minutes after the injection, HRP had largely diffused between tanycytes and hypendymal cells. As soon as 5 min after the injection, HRP had completely penetrated all the layers of the median eminence. A few labelled vesicles and lysosomes were occasionally seen in ependymal and glial cells. At longer time intervals (20 min, 1 and 4 hrs), a reaction was observed in the lumen of fenestrated capillaries of the pituitary portal plexus. In many nerve endings of the external zone, vesicles and lysosomes were seen to contain HRP. An interesting observation was the localization of HRP between nerve endings and cells in both the pars nervosa and the pars intermedia of the pituitary gland. No reaction was recorded in the anterior pituitary and the kidney. Seventeen hours after the injection, the extracellular space was free of reaction but a few positive intracellular structure were still found. These results clearly indicate that some material from the third ventricle can rapidly diffuse between cells and axons of the median eminence to reach the fenestrated capillaries of the pituitary portal plexus and the posterior pituitary without involving an active transport by tanycytes.

Animals↗
PubMed1975

Incidence of depressive syndromes in a Danish county. The Aarhus County investigation.

On the basis of a material from a cumulative registration of the psychiatric morbidity in a geographically delimited population group - the County of Aarhus with approximately 175,000 inhabitants over the age of 15 years - the frequency of depressive syndromes in psychiatric and other medical services was investigated. The material fulfils the following criteria: During the calendar years 1960 to 1964, the patients 1) were residents in the County of Aarhus, 2) had attained the age of 15 years or more, 3) had contacted at least one of the services which systematically sent information to the psychiatric register; and 4) based on an evaluation of all available data, had a main diagnosis of manic-depressive psychosis, psychogenic depression or neurotic depression. An average yearly registration rate of 1.30 per 1,000 men and 3.28 per 1,000 women was found (males: manic-depressive psychosis 0.60, psychogenic depression 0.23 and neurotic depression 0.47; females: manic-depressive psychosis 1.00, psychogenic depression 0.88 and neurotic depression 1.40). The three diagnostic groups show differences in age distribution, geographical pattern and distribution by marital status.

Adjustment Disorders↗
PubMed1975

Distribution of radioactivity in the organs of the rat and mouse after injection of (125I)alpha-melanocyte-stimulating hormone.

The distribution of radioactivity after intrajugular injection of 125I-labelled alpha-melanocyte-stimulating hormone (alpha-MSH) was studied by whole-body autoradiography of the mouse and by direct measurement of radioactivity in individual organs of the rat. Very high uptake of radioactivity in the pineal gland was measured 5 min after the injection of (125I)alpha-MSH. Lower levels of accumulation of radioactivity were found in the kidney and in the posterior (including intermediate) lobe of the pituitary. High uptake was also found in the thyroid, stomach, and oesophagus. The specificity of uptake of (125I)alpha-MSH into the pineal and pituitary is suggested by the very low uptake of Na125I into those tissues.

Adrenal Glands↗
PubMed1975

Distribution of radioactivity in the organs of the rat and mouse after injection of L-(3H)prolyl-L-leucyl-glycinamide.

The distribution of radioactivity after intrajugular injection of L-(3H)-prolyl-L-leucyl-glycinamide has been studied by whole-body autoradiography in the mouse and by direct measurement of radioactivity in individual organs of the rat. There is good agreement between results obtained with the two techniques and animal species. High levels of radioactivity were found in the pineal gland, anterior pituitary, posterior (including intermediate) lobe of the pituitary, and epididymal and brown fat. Lower uptake of radioactivity occurred in the submaxillary gland, kidney, and adrenal gland. The preferential uptake of radioactivity by the pineal gland after injection of the labelled tripeptide suggests a role for this hypothalamic hormone in the control of pineal activity.

Adipose Tissue↗