Search PubMed⌕ Search

Biomedical subjects

C Vincent

Publications and source records attributed to C Vincent.

At least 307 records · Page 17Linked to original sources
PubMed1977

Antibody response to horse gamma-globulin in recipients of renal allografts: relationship with transplant crises and transplant survival.

Anti-antilymphocyte globulin (ALG) antibody response was measured every day during and after ALG treatment in 52 recipients of renal allografts. IgM antibodies became detectable in 37 patients, usually at day 8 and IgG antibodies appeared 3 days after the IgM in 21 of 37 cases. Of 30 transplant crises recorded between days 6 and 11, 20 coincided with the onset of the antibody response, and the incidence of crises during this period was higher among antibody producers than among nonproducers. In 31 patients a partial or total unresponsiveness to ALG could be achieved. Transplant survival at 3 months was better in this group than among good responders (P less than 0.01). Anti-ALG antibody response may then be usable as an early indication of individual differences in reactivity against transplant antigens.

Animals↗
PubMed1977

[Partial synthesis of aminoglycosidic antibiotics. I. An enzymatic reactor model using cofactors].

In order to produce specifically N-monoalkylated derivatives of aminoglycoside antibiotics of potential therapeutic values, we have developed an enzymatic reactor. This system uses the aminoglycoside acetyltransferase as catalyst and acetylcoenzyme A as acetyl donor. The immobilization of one aminoglycoside acetyltransferase on different resins has been studied. The coreticulation of this enzyme on DEAE cellulose in the presence of glutaraldehyde gives rise to an enzymatic resin of high efficiency. On the other hand, we have also studied the acetylation of coenzyme A in a simple manner. Acetylation occurs in a quantitative yield when the reaction is performed in the presence of polyvinyl-4 pyridine/divinylbenzene 2 per cent. These conclusions enabled to develop two types of acetylating reactors which give rise without purification to 3-acetyl gentamicin.

Acetyl Coenzyme A↗
PubMed1976

Comparison of radio-immunoassay and lymphocytotoxicity inhibition techniques for the determination of beta2 microglobulin.

Rabbit anti-human beta2 microglobulin antisera can lyse human lymphocytes in the presence of rabbit complement. Inhibition of the lymphocytotoxic reaction by highly purified beta2m was applied to the measurement of beta2m concentration in biological fluids. Parallel determinations were also performed using a radioimmunoassay. Lymphocytotoxicity inhibition is simple and more sensitive than radial immunodiffusion but less sensitive than the radioimmunoassay. beta2m was measured by these two techniques in serum and urine from normal individuals, uremic or transplanted patients.

Beta-Globulins↗
PubMed1976

Purification of HLA antigens from urine.

HLA antigens were purified from urines of kidney transplanted patients, HLA was recovered as a single peak of 45,000 mol wt that was dissociated into beta2-microglobulin and a 33,000 mol wt fraction bearing the allospecificity. The purified fractions contain carbohydrates but no lipids. Electrophoretical mobility and the relative salt concentration of eluting buffers in DEAE-Sephadex chromatography were determined for six antigens of the A locus and seven antigens of the B locus. Isolectric points of antigens A1, A2, A9, and B12 were measured. Physiochemical characteristics of HLA purified from urine appear to be similar to those of papain-solubilized cell membrane HLA. Urinary HLA was shown to originate from serum and not from renal or ureteric tissue.

Chromatography, Affinity↗
PubMed1976

Studies on autoimmune encephalomyelitis in the guinea pig. II. An in vitro investigation on the nature, properties, and specificity of the serum-demyelinating factor.

Complement-dependent demyelinating activity of whole brain homogenate (WBH)-induced experimental allergic encephalomyelitis (EAE) sera was tested on long term tissue cultures of in vitro myelinated fetal guinea pig cerebellum. Complement-fixing (CF) auto-antibodies were shown to be the responsible agents, as demonstrated in experiments where all reagents belonged to the same species: guinea pigs of outbred (Hartley) and even of inbred (S2 or S13) strains. These antibodies were of the IgG2 class as shown by Sephadex G-200 and DEAE cellulose fractionation experiments. The corresponding auto-antigen was present in the homogenate and myelin of the central nervous system (CNS) tissue. It was different from the encephalitogenic basic protein of CNS myelin (BP), as shown in experiments where the demyelinating auto-antibodies were induced, detected, and absorbed by WBH or by CNS myelin but not by BP. They were neither induced by nor cross-reacting with cerebroside and peripheral nervous system (PNS) tissue.

Animals↗
PubMedDate not supplied

A novel approach to anticoagulation control.

Heparin used in extracorporeal therapy often leads to bleeding complications. Protamine used for heparin reversal can cause adverse hemodynamic responses. To control both types of complications, a cellulosic hollow-fiber filter device containing immobilized protamine (defined as a protamine filter) was developed. In vivo experiments with dogs showed that the filter not only removed more than 80% of the anticoagulant activity of heparin, but also caused no clinically significant hemodynamic response. In addition, the protamine filter also significantly attenuated both the thrombocytopenic and granulocytopenic responses associated with the use of protamine. Moreover, the use of immobilized protamine considerably reduced activation of the blood complement system by free protamine.

Animals↗
PubMedDate not supplied

Early CYFRA 21-1 variation predicts tumor response to chemotherapy and survival in locally advanced non-small cell lung cancer patients.

We have evaluated CYFRA 21-1 serum level variations as an indicator of tumor response and survival in 44 consecutive patients with locally advanced non-small cell lung cancer (NSCLC) treated with induction chemotherapy (IC). Irrespective of the initial CYFRA 21-1 serum concentration, a more than 65% decrease in the serum level after the first chemotherapy course was significantly predictive of an objective tumor response (p = 0.0022). In addition, a more than 80% decrease in this level significantly predicted a better disease-free survival (p = 0.039). In patients with initial CYFRA 21-1 serum levels > 3.3 ng/mL (n = 29), a more than 80% decrease after the first IC course was the most significant predictor of overall survival (p = 0.025) in a Cox analysis including initial staging, tumor response and surgery. We conclude that early monitoring of CYFRA 21-1 serum levels may be a useful prognostic tool for tumor response and survival in stage III NSCLC patients treated by induction chemotherapy.

Adult↗