Biomedicine / [publiee pour l'A.A.I.C.I.G.]最新文献

Nuclear refringence test (NRT) was studied in two inbred strains of rats: Lewis (LEW) and Wistar AG (WAG), the first develops a severe arthritis while the later only slight inflammation. Before adjuvant injection, a good NRT to ConA, PHA and Isoprinosine was observed in LEW but a poor one in WAG. After adjuvant injection a striking difference appears between the two strains concerning ConA response: in LEW the response is significantly lower on day 14, while in WAG the initial poor response is not modified. These data suggest that in WAG the suppressor T lymphocytes are already activated in vivo and are no longer responsive in vitro. The responses to PHA and Isoprinosine are parallel in both strains, the NRT response diminishes on day 14 in LEW and on day 21 in WAG.

The tube leukocyte adherence inhibition (LAI) assay was used to follow the specific antitumor immunity in patients with tumors of the urogenital tract, carcinomas of the larynx, melanomas and lung tumors. Positive reactivity was observed in more than 80% of the patients with tumor, whereas less than 5% of the controls were positive. The results show that the tube LAI assay holds promise for diagnosing and monitoring cancer diseases.

Solid tumours with histopathological characteristics of teratocarcinoma (generally presenting the structures of nervous origin) were induced in the mouse by subcutaneous inoculation with murine embryonal carcinoma (EC) cells of line PCC4-azal. An indirect immunoperoxidase technique using anti-mouse AFP antibodies was applied for the localization of the protein on paraffin sections of tissue fixed with acetic acid-ethanol. The PCC4-azal EC cells were AFP negative in vitro. In the solid tumours, the immature embryonal or fetal components (i. e. tubes or cysts mimicking the development of the neural tube) and the groups of neuroepithelial cells arranged in more or less differentiating structures (pseudotubes, cluters) were AFP positive; on the contrary, cells of the same differentiated neuroepithelial type, but lacking recognizable tissue architecture, were AFP negative. Mature, adult components were AFP negative. Undifferentiated cancer components, whether structured or not, were AFP negative. These results suggest that the intracellular presence of AFP requires a minimum degree of both cell differentiation and tissue organization.

The investigation was prompted by the observation that adriamycin can interact with heparin in vitro and reduces its anticoagulant activity in ex vivo tests in humans. The possible interactions between these two drugs were studied in C57Bl/6J mice bearing the Lewis Lung Carcinoma (3LL). The anticoagulant activity of heparin was temporarily reduced by concomitant treatment with adriamycin, as indicated by both activated partial thromboplastin times and blood recalcification times. In contrast, no changes were found in the kinetics of adriamycin disappearance from blood and accumulation in tissues if mice had been pretreated with heparin. Moreover, the effect of adriamycin on tumour and metastasis growth was unchanged by the association with the anticoagulant. These data indicate that the short-lived interaction between adriamycin and heparin, which can be documented by coagulation tests, does not necessarily involve a modification in the anticancer activity of the anthracycline.

The effects of Salbutamol 1.5 mg in 250 ml dextrose solution was tested on 14 epileptic patients following a double blind cross-over design. Sleep parameters and interictal paroxysmal activities density were measured. No seizures were encountered during the experiment. No modification of either sleep parameters (duration of sleep stages, latency of sleep and paradoxical sleep, duration of sleep cycles and awaking) or density of P. A. during waking state, on stage I, II, III and IV and paradoxical sleep were observed. In other respects, 5 patients had no P. A. during polygraphic sessions. They exhibited a longer duration of paradoxical sleep and a shorter duration of awaking than the 9 other patients with P. A. So with the dosage used here no implication of central beta-adrenoceptors in sleep mechanisms and production of epileptic activity are suggested.

Circadian (approximately or equal to 24 h), circannual (approximately or equal to 1 year) and other biological rhythms of endogenous origin, detectable at all levels of organization, constitute a temporal structure in all animal species, including man. Circadian, circannual and other rhythmic changes in biological susceptibility and response of organisms to a large variety of physical as well as chemical agents including medications and foods are rather common phenomena. Modern chronopharmacology investigates drug effects: a) as a function of biological timing and b) upon parameters characterising the endogenous bioperiodicities. A better understanding of periodic and thus predictable changes in drug effects can be attained through consideration of three complementary concepts: the chronokinetics of a drug (rhythmic changes in its pharmacokinetics): the chronesthesy (rhythmic changes in susceptibility of target biosystem to this drug), and the chronergy (the drug-integrated overall effects). One of the aims of chronopharmacology is solving problems of drug optimization. Knowledge of those administration times coinciding with best effectiveness or tolerance is required to optimize both timing(s) and dosage(s) of a medication. Illustrative examples of both experimental and clinical investigative chronopharmacology are corticosteroids and anticancerous agents.

Leucocyte-mediated phagocytosis and antibody-dependent cellular cytotoxicity (ADCC) were tested in 48 children with type-1 diabetes and in 22 healthy children. Both phagocytosis and ADCC for opsonized 51Cr-erythrocytes significantly decreased in the diabetics. Phagocytosis decreased in well and in poorly balanced diabetics, but the latter, having type-1 diabetes for less than 5 years, exhibited a lower phagocytic capacity than the patients with a longer duration of disease. The decrease of ADCC in poorly balanced patients was greater than in the well balanced ones as compared to the controls. The duration of diabetes was without influence on their leucocytes' ADCC.

A method is proposed for the determination of nitroxide-reducing capacity (NRC) of erythrocytes, and other cells, based on measurements of reduction of a nitroxide stable free radical in cell suspensions by ESR spectroscopy. Comparison of different age fractions of bovine erythrocytes by this method demonstrates a decrease in NRC during cell aging in vivo.

The results of CF and ELISA tests for cytomegalovirus performed on 270 sera of hospitalized patients show a positive correlation. As a general rule, ELISA is more sensitive than CF, except for a few sera collected from patients with immunological disorders. When two sequential sera are available, the CF remains a reliable and inexpensive method. But when only one serum can be obtained, the probability of an active CMV infection can be estimated on the IgM/IgG ratio. In 26% of the patients, this ratio was greater than or equal to 1. The ELISA is twice as expensive as the CF test. To reduce its cost, a simple method for preparing ELISA antigen from commercially-obtained CF antigens is described.