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Biomedical subjects

G Chomette

Publications and source records attributed to G Chomette.

At least 271 records · Page 15Linked to original sources
PubMed1979

[Leukoplakia and cancers of the buccal cavity. Immunofluorescence counting and typing of plasmocytes].

Immunofluorescent study of paraffin sections of 80 lesions of the buccal cavity, for the most part malignant or pre-malignant revealed marked plasmocytosis in premalignant or early malignant cases. This plasmocytosis, easily seen by the use of anti-immunoglobulin sera, is of polyclonal type, with marked preponderance of IgG secretors. In infiltrating carcinomas and in recurrences, the number of plasmocytes decreases and the percentage of IgG secretors falls markedly. By contrast, that of IgA immunocytes remains the same. The significance of these findings is considered and their practical value in the surveillance of cases of leukoplasia is stressed.

Animals↗
PubMed1979

[Glomerulopathy during Behçet's syndrome. Immunofluorescent and electron microscopy studies (author's transl)].

Full renal investigation were conducted in 11 patients with Behçet's syndrome. Biological tests revealed the presence of mild proteinuria in 5 of them. Needle biopsy showed extra-membranous or mesangial fibrinoid deposits in 6 cases, associated in 1 case with segmental and focal glomerulitis lesions. Immunofluorescence studies demonstrated glomerular deposits of mesangial and extra-membranous C3, sometimes with immunoglobulins (IgA-AgG). Ultrastructural examination was carried out in 7 cases and showed "hump" deposits attached to the external face of the basal membrane and rounded nodules of 7 to 15 mu included in the mesangium. The presence of immune complexes in the renal glomeruli, therefore, is not all unusual in this disease, which is probably auto-immune in nature, and in fact appears to be a quite frequent occurrence. These deposits, which were probably well-tolerated by most of the patients in this series, might be involved in the production of progressive glomerulopathies in chronic cases, as observed in one of the cases studied.

Adolescent↗
PubMed1979

[Conduction abnormalities after single heart valve replacement (author's transl)].

A total of 300 patients were operated upon for heart valve disease by the same surgeon. The affected valve was the aortic in 200 cases and the mitral in the other 100 patients. The tricuspid valve, coronary arteries, and myocardium were not involved. This report attempts to define the frequency progression, prognosis, and significance of conduction abnormalities which appear during the course of this operation. In 35 cases, of which 16 were post-operative deaths, a histological examination of the conduction pathways was possible. The conclusions to be drawn from these observations are: Conduction abnormalities after single aortic or mitral valve replacement are frequent (1 out of 3 patients).

Aortic Valve↗
PubMed1979

[2 cases of alveolar sarcoma. Study by electron microscopy and cytoenzymology].

Study by electron microscopy and light cytoenzymology of two cases of alveolar sarcoma of the thigh occurring in young men indicated it to be an active tumour with an apparently functional organoid arrangement, characterised by an abundance of capillary vessels. The secretory nature of the cell elements was suggested by the marked development of smooth and granular reticular systems. The morphological result of this secretory activity was constituted by vesicular bodies with dense contents, surrounded by a membrane and sometimes containing periodic paracrystalline structures. This intravacuolar crystalline organisation goes hand in hand with an increase in acid phosphatase activity suggesting possible crinophagia. Amongst the different hypotheses advanced in the past, the morphological appearances seen here would most likely correspond with the endocrine nature of this tumour.

Adult↗
PubMed1978

[The hepatocyte in acute alcoholic hepatitis. Histoenzymological and ultrastructural analysis (author's transl)].

The interpretation of the morphological features of alcoholic hepatitis is discussed in terms of a comparison with the results of an ultrastructural and histoenzymological study of the liver biopsies of nine patients. In these patients liver biopsies were performed in the initial stage of the illness and fifteen days after five were re-biopsied, when the clinical and biological signs were improved. The correlations between morphological and biological data were good, especially for the levels of serological and histoenzymological alkaline phosphatase and gamma-glutamyltranspeptidase evaluations. However, when histological appearances had returned to normal, after two weeks of abstinence from alcohol several histological and ultrastructural features of the initial hepatitis persisted. The presence of evolving cirrhosis was a contributing factor to the severity of the changes seen. Morphologically, apart from the changes due to chronic alcoholic intoxication (steatosis, mitochondrial alteration), the hepatitic lesions comprise Mallory's bodies, cytoplasmic oedema and mitochondrial swelling. Cholestasis was invariably present. Histo-enzymologically there was a reduction in ATPase activity suggesting a metabolic failure in the energy producing pathways. In addition, in the periphery of lobules an active cirrhotic process was present, with tubular de-differentiation of hepatocytes and an increase in gamma-glutamyltranspeptidase on the cytoplasmic membrane. Because of the absence of any topographical relationship between hepatitis and cirrhosis, the presence of lymphocytes in the neighbourhood of the ductules suggested an indirect relationship between both processes, perhaps an autoimmune response initiated by Mallory's bodies.

Adenosine Triphosphatases↗
PubMed1978

[Primary sarcoma of the pulmonary artery of the hemangioendotheliosarcoma type].

A case of primary sarcoma of the pulmonary artery presenting with the symptomatology of a bronchopulmonary tumour is studied in comparison with those reported up to the present in the literature. The tumour, examined in the pneumonectomy specimen, appeared to be inserted into the trunk of the left pulmonary artery with unusual propagation in the distal arteries. It had also spread into the neighbouring bronchial lumina. Histologically, the appearance was, rarely, that of a haemangioendotheliosarcoma. The histogenesis of these neoplasms is briefly discussed.

Aged↗
PubMed1978

[Malignant hemangiopericytoma. Apropos of the ultrastructural and histoenzymological analysis of a case].

The histoenzymological and ultrastructural study of a haemangipericytoma with the clinical and histological characteristics of malignancy led to the identification within the tumour, in addition to pericytes and more differentiated cells, fibroblastic or muscular, of younger cells. The latter, arranged in cords undergo multiple appearances of transformation to result in a double maturation, at one and the same time pericytic and angio-endothelial, rarely seen up to the present in haemangipericytomas.

Acid Phosphatase↗
PubMed1977

High-dose irradiation in the pig small intestine. Histoenzymology and electron microscopic study.

The early and late effects of a single high-dose irradiation (100 rad) in the pig small intestine have been studied by histoenzymology and electron microscopy and related to some functional data. 1) The initial atrophy induced by the irradiation appears late (on the 6th day), compared to other species. This is due to the fairly long regeneration time of the villi epithelium in the pig. 2) The initial lesions are similar to those observed in different experimental models (nuclear alterations, karyolytic bodies, etc.). They particularly involve the crypts, and are specially focused in the undifferentiated cells of GS phase or mitosis, but also in goblet and Paneth's cells. 3) The villi regeneration, over on the 23rd day, is preceeded by an active mitotic phase which first renews the undifferentiated cells. This mitotic activity, reaching its highest value on the 16th day, goes on during the whole regeneration period itself. 4) At the beginning, this regeneration is denoted by the high esterase activity of the crypt collar. It appears in many goblet cells and also in some absorptive cells which show, at once, some of the enzymatic activities of the striated border. However, for a short period, lipid absorption is quantitatively reduced. This is connected with the temporary cell immaturity (up to the 20th day) and to the poorly developed rough endoplasmic reticulum and Golgi apparatus. 5) Further on, the persistence of a malabsorption syndrome (lipids, calcium) is not connected, for the main point, with modifications of the morphology or the cytology of the villi (in spite of the abnormally high number of goblet cells and the presence of few pathologic absorptive cells). It is, in fact, related to the persistence of an inflammatory state of the lamina propria associated with an exudative enteropathy. The meaning of this last finding is not clear: it could depend on a primary infectious state due to the modifications of the endoluminal intestinal flora, or, rather, on a secondary infection supported by the trophic epithelial disturbances induced by a continuous vascular dyshoria due to the irradiation.

Animals↗
PubMed1977

[Hairy cell leukemia in the spleen (author's transl)].

Fifteen spleens with hairy cell leukemia are studied with immunofluorescent (7 cases), electron microscopic (5 cases), and usual histologic methods. The findings are: enlargment of the spleen (weight always superior to 400 g), diffuse red pulp infiltration by ambiguous cells with regular repartition of nuclei and clear spaces between them, hairy aspects of the cytoplasmic membrane which are especially observed on semi-thin and ultra-thin sections, presence of particular cytoplasmic inclusion bodies (polysome lamellae complex). The cellular infiltration is accompanied by some vascular modifications: pseudo angiomatosis lesions, nodular formations ressembling splenomas. An important hypertrophy of the splenic macrophages with erythrophagocytosis and siderosis is also observed. These two phenomena partly explain the anemia.

Erythrocyte Aging↗
PubMed1977

[Morphological aspects of the bone marrow in hairy-cell leukemia].

Bone marrow plays a considerable role in the diagnosis of hairy cell leukemia. The morphological aspects should be well known. One should emphasize the existence of aplastic or hypoplastic forms requiring one to repeat biopsy on the slightest clinical suscpicon. Routine histological techniques are sufficient for the diagnosis. The ultrastructural study also provides valuable histological and cytological evidence.

Adult↗