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Biomedical subjects

F Robert

Publications and source records attributed to F Robert.

At least 181 records · Page 10Linked to original sources
PubMed1979

T and B lymphocytes in pituitary dwarf Snell-Bagg mice.

The lymphocyte composition of the thymus and spleen from weaned (4 month old) hypopituitary dwarf Snell-Bagg mice were compared to those of their phenotypically normal littermates and of hormone (somatotropic hormone plus thyroxine)-treated individuals. Detection of cells bearing receptors for peanut agglutinin, physical analysis and measurement of in vitro reactivities to phytohaemagglutinin and concanavae intra-thymic lymphocyte population of dwarf mice. Examination of spleen-cell suspensions demonstrated a slightly higher frequency of T lymphocytes (Thy 1-2+ alpha-Naphthyl esterase+, high electrophoretic mobility) and lower frequency of B lymphocytes (surface immunoglobulin+, low electrophoretic mobility) in dwarf mice than in control mice. The degree of splenocyte responsiveness to T- and B-cell mitogens, however was similar in the two mouse types. High mobility (T) splenic cells were found to exhibit a smaller modal volume in dwarf mice (110 micron3) than in control mice (122 micron3) but this difference was not corrected by hormone administration. More pronounced were the quantitative differences between the spleens of hormone-deficient and normal mice. Thus, when expressed as a function of body weight, the numbers of splenic T and B lymphocytes in untreated dwarf mice were about half the corresponding values in hormone-reconstituted or normal littermates. These data suggested that in adult life, developmental hormones exert little direct effect on the thymus lymphocytes but influence the size of the pool of both peripheral T and B lymphocytes.

Animals↗
PubMed1979

Single cell analysis of changes in electrokinetic properties of a growing ascitic tumor.

An ascitic tumor (SEWA) induced by polyoma virus in A.SW mice was analyzed in vivo as well as in vitro with regard to the electrophoretic mobility (EPM) which may be considered as a reliable criterion of surface charge. After the i.p. transplantation of 10(5) cells, the EPM decreased up to 14th day. Then, the mobility gradually increased with the age of the tumor. In the first phase of tumor growth, we have considered the possibility that immunoglobulin cell coating may be responsible for the decrease in EPM. In the late phase of SEWA growth, the progressive increase in EPM might be due to a rearrangement of sialic acids on the outer part of the cell membrane.

Animals↗
PubMed1978

Identification of human anterior pituitary cells by immunoelectron microscopy.

An attempt was made to classify human pituitary cell types by electron microscopic immunohistochemistry. The immunoperoxidase technique involving the use of the peroxidase-antiperoxidase complex was applied to thin sections of human pituitaries removed surgically for breast cancer or diabetic retinopathy. Using specific antibodies against human PRL, GH, beta-FSH, beta-LH, beta-TSH, and porcine ACTH, the localization of each hormone was studied. Identification of 5 human pituitary cells was possible: 1) The PRL-secreting cell contains round or slightly ovoid secretory granules of a diameter of 275-350 nm. 2) The GH-secreting cell is densely granulated with granule diameters ranging from 350-500 nm. 3) The gonadotrophic cell, which stains for both beta-FSH and beta-LH, is characterized by the presence of a varying number of secretory granules ranging from 275-375 nm. 4) The cortico-lipotrophic cell has numerous granules of about 375-550 nm in diameter. 5) The TSH-secreting cell contains small secretory granules of about 125-200 nm in diameter. Another cell type of which the small secretory granules of about 100 nm in diameter could not be stained by any of the antisera was also observed. This ultrastructural identification of human pituitary cells should contribute to a better understanding of the pathophysiology of the human pituitary.

Adrenocorticotropic Hormone↗
PubMed1978

Pituitary adenomas in Cushing's disease. A histologic, ultrastructural, and immunocytochemical study.

Twenty-two pituitary adenomas in Cushing's disease were removed by transsphenoidal surgery. In six patients the pituitary tumor had become manifest following adrenalectomy (Nelson's syndrome). Sixteen tumors were microadenomas measuring from 2 to 9 mm, while two were diffuse invasive adenomas verified at postmortem examination. Light microscopy showed that the tumors were made of basophillic cells containing PAS-positive granules that stained blue with Herlant tetrachrome and lead hematoxylin. Immunocytochemical studies showed that the granules stained positively with antiserum to adrenocorticotrophic hormone (ACTH) or to beta-lipotropic hormone (beta-LPH) and the peroxidase-antiperoxidase complex. Electron microscopic study of the tumor cells showed ACTH and beta-LPH containing granules varying in size, shape, and amount. Perinuclear bundles of 70 A microfilaments constituted a specific ultrastructural finding.

Adenoma↗
PubMed1977

[Criteria of brain death. Spinal reflexes in 45 personal studies].

In 45 patients without spontaneous breathing or cranial reflexes, and in whom blood pressure had to be supported, spinal reflexes were obtained in 60% and polysynaptic spinal reflexes in 33%. In all cases angiography showed cerebral circulatory arrest and/or repeated EEG recording gave an isoelectric line. The presence of spinal reflexes, appearing most frequently 6-36 h after death (which we defined as a sudden fall in blood pressure below 80 mm Hg with absence of spontaneous breathing) is not in contradiction with the assumption of brain death. 9 patients without signs of intoxication showed, in addition, a fall in body temperature below 34 degrees C. Such a fall in body temperature also in agreement with the diagnosis of brain death.

Adolescent↗
PubMed1977

Mucosal eosinophilic gastroenteritis with systemic involvement.

The unusual features in a 46 year old white woman with mucosal eosinophilic gastroenteritis are described. In addition to involvement of the gastrointestinal tract, she had eosinophilic splenitis and hepatitis. She responded to corticosteroid therapy, but not to an elimination diet or to cromolyn sodium therapy. The possible role of various factors chemotactic for eosinophilia in the patient are reviewed, and the place of the disorder among the hypereosinophilic syndromes is discussed.

Chemotaxis↗
PubMed1977

Cure of Cushing's disease by transsphenoidal removal of a microadenoma from a pituitary gland despite a radiographically normal sella turcica.

A 37-year-old woman had symptoms of Cushing's disease for two years. Galactorrhea was present. The diagnosis was confirmed by finding intermittently elevated urinary 17-hydroxysteroids, absent circadian rhythm, and elevated plasma ACTH. Plasma prolactin was slightly elevated. Films of the sella turcica were normal. A 9 mm basophilic microadenoma was removed by the transphenoidal approach. Immunocytochemical and electron-microscopic studies showed that the tumor was composed exclusively of ACTH secreting cells. Endocrine re-evaluation one year later revealed normal adrenal function. Serum prolactin had returned to normal. This case provides further evidence that Cushing's disease can be caused by a pituitary microadenoma insufficient in size to deform the sella.

Adenoma, Basophil↗
PubMed1977

Demonstration of Cryptococcus neoformans in a stained bone marrow specimen.

Disseminated cryptococcosis is seen with increased frequency in patients with malignant hematologic disease. Usually the diagnosis rests on spinal fluid studies, and little attention has been paid to the direct examination of a bone marrow specimen. A febrile woman with an advanced histiocytic lymphoma was intensively treated with antineoplastic agents; the antemortem diagnosis of cryptococcosis was suspected from direct examination of the bone marrow and was subsequently confirmed by culture. Visualization of fungi in special stained bone marrow specimens could be useful in the initial examination of febrile patients with neoplastic diseases and/or compromised host defenses, and would permit early institution of specific therapy.

Bone Marrow↗
PubMed1977

Changes in the electrophoretic mobility of mouse lymph node lymphocytes during ontogeny.

The electrokinetic properties of peripheral lymph node (LN) cells from C3H and nude mice aged 1, 3 or 10 weeks, were investigated by means of preparative and analytical cell electrophoresis. Two groups of cells were distinguishable throughout the age interval examined. The first group, with low-mobility (LM) included the majority of surface-immunoglobulin positive lymphocytes, was predominant in athymic nude mice and is thus likely to represent B cells. The other group, with higher mobility (HM), was sensitive to anti-Thy 1-2 serum, made up the major LN population in C3H mice and normal nude littermates and thus probably corresponds to T cells. In C3H mice, the relative proportion of LM cells was found to increase with age of LN donors (from 9-22%). Moreover, significant alterations in the mean electrophoretic mobility (EPM) of both lymphocyte populations were detected in the course of development. While the EPM of LM cells diminished from 0-81-0-70 micrometer.s-1.V-1.cm, that of HM cells increased from 1-11-1-22 micrometer.s-1.V-1.cm as the animals grew from 1-10 weeks. These observations indicate a relationship between the degree of maturity of peripheral B- and T-cell populations and their electrokinetic properties.

Animals↗