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Biomedical subjects

A Pompidou

Publications and source records attributed to A Pompidou.

At least 55 records · Page 3Linked to original sources

Early nuclear structural changes of transformed human amniotic cells (WISH) in presence of type IV collagen detected by the nuclear refringency assay.

An early nuclear activation of transformed human amniotic epithelial (WISH) cells triggered by type IV collagen is visualized by a modification of the nuclear refringency obtained by mercury binding on condensed chromatin. This phenomenon is quantified by the nuclear refringency test. The nuclear activation of WISH cells by basement membrane collagen is also shown by the DNase I sensitivity of chromatin and by the measurement of mRNA synthesis. These nuclear phenomena are concomitant with WISH cell attachment and laminin synthesis. Reversible effects on nuclear refringency, cell attachment, and laminin synthesis are tested by the addition and removal of different metabolic inhibitors.

Amnion↗

Rat and human polymorphonuclear leukocyte derived lymphocyte stimulatory factors.

The kinetic release of lymphocyte activating factors by inflammatory rat polymorphonuclear leukocytes (PMNs) into culture fluid was studied. PMNs, collected from the pleural cavity of rats 4 hours after injection of either calcium pyrophosphate (CaPP) or normal plasma, released into the supernatant culture fluid, factors which enhanced the phytohaemagglutinin-induced proliferative response of normal lymph node cells or thymocytes, the optimal culture time being 24 hours. A major portion of these lymphocyte activating factors was found in the ultrafiltrates (less than 10,000 daltons) of PMN supernatants. The activities in both unfractionated supernatant and the ultrafiltrate were significantly enhanced if PMNs were exposed to Concanavalin A (Con A) or inflammatory exudate prior to supernatant production. Also, these were not species specific as rat PMN supernatant can stimulate the phytohaemagglutinin-induced response of human lymphocytes and, conversely, human PMN factors can stimulate rat thymocytes.

Animals↗

The enhancement of interleukin 2 like production after in vivo stimulation of rat lymphoid cells by an acute non specific inflammatory process.

Interleukin 2 (IL 2) production was studied in lymphoid cells from rats undergoing an acute non specific inflammatory reaction induced by intrapleural injection of calcium pyrophosphate. Spleen and lymph node cells derived from inflamed animals had an increased level of IL 2 like production compared to cells from normal animals. Thymocytes also showed enhanced IL 2 like production although the absolute levels were lower than spleen or lymph node cells. It has been suggested that the acute non specific inflammatory reaction is able to modify lymphocyte reactivity via IL 2 and interleukin 1 (IL 1). The nature of the humoral factors released by the inflammatory process which are capable of initiating these events is also discussed.

Acute Disease↗

[Study of cellular immunity by the nuclear refringence test during general anesthesia].

The authors studied early changes in immune state by the nuclear refringence test in 12 patients undergoing gynaecological surgery for non-malignant conditions. The test was performed before and thirty minutes after the induction of anaesthesia. Twenty five per cent of the patients showed abnormalities of the nuclear refringence test in the presence of Con A2. The interpretation of the results and the predictive value of the test are discussed.

Adult↗

Lymphocyte nuclear refringence in two inbred strains of rat. Modifications of NRT during adjuvant arthritis.

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.

Animals↗

Role of nucleic acids and cytoskeleton in nuclear refringence phenomenon (nrp) of human peripheral blood lymphocytes.

Nuclear refringence is a phenomenon visible by light microscopy that is correlated with lymphocyte maturation and activation. The present study, in employing isolated nuclei as well as intact lymphocytes, confirms the nuclear basis of the phenomenon. Enzymatic degradation of nucleic acids in isolated nuclei attenuates refringence, providing presumptive evidence for the involvement of chromatin in refringence. Cytoplasmic events involving RNA and protein synthesis and microtubular, but not microfilament, function are necessary for the maintenance of refringence. These studies provide the basis for evaluating refringence within the context of nuclear protein changes known to occur during lymphocyte activation and for determining its usefulness as a simple test of the dynamic state of the lymphocyte nucleus.

Amanitins↗

[Change in rabbit blood lymphocyte count after repeated extracorporeal irradiation with cesium 137. Comparison of heparin and acenocoumarol effects].

During repetitive extracorporeal irradiation, heparin treatment is responsible for a very high lymphocytic peak which does not last more than two days. This peak is not observed after using acenocoumarol as anticoagulant. That is why the degree of lymphocyte depletion after RECIB is to be interpreted in function of the anticoagulant used. This peak is temporary. No matter the anticoagulant used, lymphopenia is obtained after 15 days. The level of lymphocytic depletion is independent of the initial lymphocytosis.

Acenocoumarol↗

[Repeated extracorporeal irradiation of rabbit blood (RECIB). Effect on lymphocytes].

Haemotological data are described after repetitive extracorporeal irradiation of blood (RECIB) is rabbits for two hours a day, five days a week. Cesium 137 can deliver 125000 rads/hour, i.e. a cummulative dose equivallent to 1.25 X 10(6) rads/week. The blood lymphocytes were investigated in detail, lymphopenia was obtained after 15 days and remain stable after the third week.

Animals↗

Blood lymphocytes in acute lymphoid leukaemia in remission and in relapse. Predictive value of electrophoretic mobility and refringence.

Blood lymphocytes were studied during the evolution of acute lymphocytic leukaemia, including remissions and relapses, under chemotherapy and immunotherapy. Lymphoblasts migrate as a uniform population and have a mean electrophoretic mobility of 1.04 mum-sec-1. V-1cm. These lymphoblasts are also refringent. The relapse seems to be preceded by a slowing of the electrophoretic mobility of fast cells and a rise in the percentage of refringent lymphocytes.

Adolescent↗