Biomedical subjects
Publications and source records attributed to J F Charles.
Report of one case of Caroli's disease (congenital ectasy of segmental intra-hepatic bile ducts) associated with congenital hepatic fibrosis, in which arised clear cell biliary carcinoma. This event seems to be very rare. In our case, the bile duct dilatation was associated with renal polycystic diseases.
Crystals isolated from Bacillus thuringiensis serovar thuringiensis (H-1) and from serovar israelensis (H-14) were dissolved in sodium hydroxide, then tested in vitro on Aedes aegypti cell cultures. Toxic action was followed after morphological and metabolic alterations of the treated cells. Only the israelensis sodium extract was toxic and gave cellular swelling, inhibition of cell growth and inhibition of labelled precursor incorporation, i. e. of 3H-thymidine, 3H-uridine and 3H-leucine.
The effects of Bacillus thuringiensis var. israelensis delta-endotoxin were investigated on a cell culture of Aedes aegypti with the electron microscope. The ultrastructural changes following intoxication were: disintegration of endoplasmic reticula by the formation of spherical structures; condensation and then swelling of mitochondria with disappearance of internal cristae; frequent dilatation of the perinuclear space; cellular lysis. The action of a metabolic inhibitor, 2,6-dibromophenol (2,6-DBP), was tested for comparison: beyond condensation of mitochondria, no changes in other cell structures were observed. These data seem to indicate that the mode of action of delta-endotoxin is quite different from that of 2,6 DBP.
Ingestion of Bacillus thuringiensis var. israelensis crystals by Aedes aegypti larvae is followed by midgut epithelium disruption. Earliest ultrastructural changes consist of an enlargement of intra- and intercellular spaces in the basal region of the cell. Endoplasmic reticula disintegrate by forming spherical structures which increase in size during intoxication. Mitochondria are transformed at first into a condensed form, then become swollen with the disappearance of internal cristae. In the cardia cells, which secrete the peritrophic membrane, the Golgi apparatus may produce electron-dense secretion vesicles; in this event, the peritrophic membrane assumes an abnormal configuration. Before complete breakdown, a cellular hypertrophy is observed: few cells become balloon-like. At the same time, the microvilli decrease in size, widen and then disappear after a few hours exposure to crystal delta-endotoxin.
The sporulation and crystal development of Bacillus thuringiensis serotype H-14 was described for a wild spore- and crystal-forming strain and for a mutant crystal but non spore-forming strain. The special nature of the israelensis var. consisted in the composite structure of the crystal, made of a number of components differing in size, shape and electron density. The components were formed in a single inclusion or sometimes separately inside the same bacterial cell.
After feeding Aedes aegypti larvae with B. thuringiensis var. israelensis crystals the very alkaline pH (greater than or equal to 10) of the anterior midgut remains stable during the first twenty minutes, in spite of important cytological damage. Thereafter, the pH drops to surround the neutrality and the death occurs. These results are discussed according to the knowledge on the action of B. thuringiensis var. israelensis.
Basing their observations on 11 cases treated personally and 74 cases reported in the published literature, the authors use the histological findings and the course taken by the lesions to separate pancreatic cystadenomas into microcystic adenomas and mucinous cysts. Their classification as a single clinical entity is justified by their almost indentical symptoms : usually of large size and seen mainly in women. A more precise diagnosis requires the use of complementary examinations including ultrasonography, arteriography, and computed tomography. Microcystic adenomas occur throughout the gland and are always benign : mucinous cysts are found mainly in the head or tail regions and may become malignant. Histological examination of the whole lesion is necessary in order to recognize a primary malignant form, and radical excision is required. The risk of changes in any cystic lesion, therefore, implies that controlled excision should be employed rather than simple cystectomy.
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Hormono-dependent epithelial cells of the prostate gland loose their histologic and cytologic differentiation when becoming neoplastic. Such loss of differentiation is related to a change in testosterone metabolism measured by the testosterone metabolites ratio (17 beta-hydroxy/17-oxometabolites). This ratio decreases with differentiation losses and increasing independence from androgenic steroids. Knowledge of that ratio is suggested, prior to the starting of antiandrogenic therapies.