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Biomedical subjects

Y Mallet-Guy

Publications and source records attributed to Y Mallet-Guy.

At least 19 recordsLinked to original sources
PubMed1984

Structure and composition of microcalcifications in benign and malignant lesions of the breast: study by light microscopy, transmission and scanning electron microscopy, microprobe analysis, and X-ray diffraction.

Microcalcifications previously located by radiography were extracted from 25 fresh specimens obtained from patients who had undergone tumorectomy or systematized mammary exeresis. Two principal types of microcalcifications were distinguished: Type I microcalcifications were amber in color and generally crystalline on scanning electron microscopy, with only one calcium peak on microprobe analysis; x-ray diffraction revealed that weddellite was involved. Type II microcalcifications were whitish, nonbirefringent under polarized light, and generally ovoid or fusiform, with two peaks, one calcium and the other phosphorus, on microprobe analysis; these microcalcifications were composed of calcium phosphate, the most characteristic form of which is hydroxyapatite, in the form of needles arranged in rosettes on transmission electron microscopy. Type I microcalcifications were observed in four of eight benign breast lesions, in two of three in situ lobular carcinomas, and in no intraductal adenocarcinomas or infiltrating carcinomas. Type II microcalcifications were present in all infiltrating carcinomas and intraductal adenocarcinomas; they were also found in benign lesions (four of eight) and even associated with type I microcalcifications in one in situ lobular carcinoma. There are, therefore, no "benign" or "malignant" microcalcifications; however, the presence of weddellite is a strong indication that a lesion is benign or, at most, an in situ lobular carcinoma.

Adenocarcinoma↗
PubMed1984

[Byler's disease. Ultrastructural study. Apropos of a case in an infant].

A case of familial cholestasis with cirrhosis is described in a 8 months old boy, presenting with hepatosplenomegaly, portal hypertension, dramatic pruritus, and fluctuating icterus of early post-natal onset. Biological data include positive hepatocyte retention test, with mild hepatocyte cytolysis, without patent hepatocyte insufficiency. The discrepancy between the clinical symptoms and a slight elevation of bilirubin partially conjugated, the absence of elevated blood cholesterol, the absence of evidence of antigen or antibody of virus A or B, the marked elevation of blood biliary acid lead to the suspicion of Byler disease. A liver biopsy with ultrastructural study shows a thickening of the ectoplasm, and the presence of microfilament material in the lumen of partially broken villi. Comparisons are made with the 4 other cases of Byler disease with E.M. study documented in the literature.

Bile Acids and Salts↗
PubMed1982

[Amphicrine, mucoid and argyrophile tumors of the breast. Histochemical and ultrastructural study of 2 cases].

The authors report two cases of mucoargyrophilic carcinomas of the breast, occurring in 73 and 81 year old women. Both tumors consist of a central mucoid carcinoma surrounded by solid areas with lobular or endocrinoid features. Most cells showed an abundant eosinophilic granular cytoplasm or a mucinous appearance. The histochemical reactions (Grimelius-Alcian Blue, Grimelius-Mucicarmine) and the ultrastructural study of the peripheral areas disclosed several cell types: poorly differentiated or mucinous cells were present in both cases; but most of the cells were argyrophilic and contained in their hyaloplasm numerous dense core "neurosecretory" granules; such cells revealed many microfilaments arranged in bundles or in whorls. Amphicrine cells were easily demonstrated by histochemical staining and their cytoplasm showed both endocrine granules and mucinous vesicles. These features suggest a possible relationship to other argyrophilic tumors of the breast. The histogenesis of these tumors is still little known.

Adenocarcinoma, Mucinous↗