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Biomedical subjects

C Aubert

Publications and source records attributed to C Aubert.

At least 145 records · Page 8Linked to original sources
PubMed1976

Ultrastruct and biochemical chantes in cultured human malignant melanoma cells after heterotransplantation into nude mice.

Cells from three lines of cultured human malignant melanomas were heterotransplanted into nude mice and then recultered. The shape of the cells, the aspect of the melanosomes, and the content of 5-S-cyteinyldopa showed pronounced changes induced by the transplantation. Such results indicate that this experimental model should be used with great caution. A relationship was found between the shape of the melanosomes and the content of 5-S-cysteinyldopa in the cells.

Animals↗
PubMed1975

[Perturbations of the levels of hypophyseal serotonin induced by oral administration of a single dose of 7, 12-dimethyl 1-2 benz(a)anthracene in rats].

Pituitary serotonin was estimated by fluorescence technique in rats fed with DMBA at 30 days, 60 days or 90 days age. In the rats most receptive to this carcinogen, serotonin was found to be decreased to 40% of control values, for the 8 days period studied. A possible mechanism leading to hormonal unbalance is proposed.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1975

[Formation of norapinephrine in the rat brain after administration of ((+)-erythro-3,4-dihydroxyphenylserine(author's transl)].

Fluorescence microscopy of rat brains after administration of (+)-erythro-DOPS has been studied. (+)-erythro-DOPS induced an increase of brain NE part of which was formed in the capillary walls. The slight diminution of this increase when (+)-erythro-DOPS was administered after inhibition of peripheral decarboxylase, might result from the algebraic sum of two inversely acting processes: suppression of NE synthesis in the capillary walls and enhancement of parenchymatous NE in some brain areas. (+)-erythro-DOPS enters different brain structures non specifically and NE is formed in DA and 5-HT systems, displacing the amines especially at the terminals; the NE formed by (+)-erythro-DOPS in NE systems should be rapidly catabolised. Possible pharmacological effects of (+)-erythro-DOPS administration involve consideration of the lack of topical specificity of NE formation; the displacement of 5-HT and DA; and the fact (+)-erythro-DOPS produces (+)-NE, and not naturally occurring NE.

Animals↗
PubMed1975

Differentiation of melanocytes in cultures of primary malignant melanoma indicated by 5-S-cysteinyldopa formation.

The dedifferentiation of cultured primary human malignant melanocytes was not accompanied by disappearance of 5-S-cysteinyldopa formation. The addition of conditioned medium from undifferentiated fibroblast-like cells brought about the reappearance of pigmented melanocytes and the increase of the metabolite in the cells and culture medium. The presence of 5-S-cysteinyldopa in cultured cells indicated the melanocytic origin of undifferentiated cells, and the increase of this metabolite was characteristic of differentiation.

Cell Differentiation↗
PubMed1975

Cell-mediate cytotoxicity in vitro of human lymphocytes against a tissue culture melanoma cell line (igr3).

Purified peripheral blood lymphocytes from 13 healthy donors, 6 melanoma patients and 1 halo nevus patient were tested for cytotoxic activity against an allogeneic melanoma cell line (IGR3) in, at least, one of the following assays: cell-mediated cytotoxicity (ADCC) and microcytotoxicity assays (ma). The lymphocytes were isolated by Ficoll-Triosil gradient centrifugation (fraction F) followed by removal of iron-phagocytosing and adherent cells (fraction FFF) and by subsequent passage through anti-IgG columns (fraction FFF-C). Leukocytes of each fraction were identified by different methods including morphology, rosette-formation, phagocytic activity, and membrane fluorescence. CMC activity paralled ADCC activity at a log lower level of sensitivity. In both assays lymphocytes of fractions F and FFF had the highest activity, whereas in fraction FFF-C cytotoxicity was strongly reduced. In all three lymphocyte fractions CMC and ADCC activity could be blocked by preincubation of the effector cells in aggregated IgG. Furthermore, depletion of E rosette-forming lymphocytes slightly increased ADCC and CMC activity, whereas depletion of EA and EAC rosette-forming lymphocytes strongly decreased it. Our results therefore indicate that in both CMC and ADCC assays, non-adherent, non-phagocytic Fc receptor-bearing lymphocytes ("K" cells) were the active cytotoxic cells. In MA, on the other hand, mononuclear phagocytes seemed to be the most active cell population. So far no significant difference was observed in CMC, ADCC, and MA between control persons and melanoma patients

Animals↗