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Biomedical subjects

R Plagne

Publications and source records attributed to R Plagne.

At least 73 records · Page 4Linked to original sources
PubMed1983

Study of cell changes induced by radiolabelling of human lymphocytes with 99m-technetium.

With the aim of evaluating cell changes possibly induced by labelling lymphocytes with 99m-technetium (99mTc), several rosette tests and stimulation assays with mitogens have been carried out before and after radiolabelling. The results presented here show that (i) as the rosette tests are not modified statistically, the original labelling method does not seem to induce short term membrane structure modification and (ii) as stimulation by mitogens decreases after labelling with 99mTc, medium term radiation damage, linked to autoirradiation of the cells, can be evoked. This study indicates that there is reason to limit the time taken to perform scintigraphic explorations with labelled lymphocytes in man.

Cell Survival↗
PubMed1982

Follow-up results from a randomized trial for T3 and T4 breast cancer patients: previous BCG immunotherapy improves response to chemotherapy in the relapse patient.

Following locoregional treatment, patients were randomized into three groups: The first groups received no complementary treatment; the second group received adjuvant chemotherapy (vincristine, cyclophosphamide, and 5-fluorouracil once a month for 12 months); and the third group was treated by immunotherapy (150 mg BCG once a week for 1 year). Sixty-two of the 82 patients studied were menopausal. No significant difference was observed between the three groups. All patients were followed-up for at least 18 months. The disease-free interval difference between the chemotherapy group and the control and immunotherapy groups is not significant. But it should be noted that only 21.8% of the control group did not relapse compared to 57% in the chemotherapy group. BCG immunotherapy in such patients must be considered ineffective. However, our results suggest that patients first treated with BCG respond better to chemotherapy than patients not receiving any previous therapy.

Breast Neoplasms↗
PubMed1982

Follow-up of a randomized trial for oat cell carcinoma evaluating the efficacy of peripheral intravenous nutrition (PIVN) as adjunct treatment.

A randomized trial was initiated to compare the effects of peripheral i.v. nutrition (PIVN)-associated chemotherapy (adriamycin, vincristine, VP-16-213, and cyclophosphamide) versus a chemotherapy control group in patients with oat cell lung carcinoma. Thirty-nine evaluable patients were randomized. The test group included 19 patients, whereas 20 were followed in the control group. PIVN was scheduled each day the patient underwent chemotherapy. Each patient received 1,550 kcal day which included 10% glucose, 20% lipids, and amino acids which may or may not have been mixed in the same infusion bottle. The results show ten PIVN patients presently in complete remission at the end of three courses of treatment, compared to nine over the same time period in the chemotherapy control group. Thirty-three percent of patients are still alive after 15 months after the beginning of treatment. There was no significant difference in either general health or side effects, frequency or duration of complete remission, or survival time. After 1 year of treatment, 8 of 19 PIVN patients are still in complete remission, compared to 7 of 20 patients in the control groups.

Carcinoma, Small Cell↗
PubMed1982

Labeling of human lymphocytes with 99mTc by means of stannous pyrophosphate. Scintigraphic applications.

An original 99mTc-labeling method applied to human lymphocytes is described. This technique is based on the use of stannous pyrophosphate to reduce sodium pertechnetate. The proposed procedure has two main advantages: firstly, the labeling process takes place in a neutral and buffered medium which prevents any cellular aggregation; secondly, the labeling yield obtained is compatible with scintigraphic studies in man. The influence of each parameter on the labeling quality had been studied as well as the binding stability of the technetium fixed on cells. A systematic study of lymphocyte surface markers, before and after labeling, has led to the suggestion that the labeling process seems to affect cellular membranes, probably because of the technetium binding. Finally, scintigraphic results are presented, the study being performed on eight healthy volunteers. These results are compared with those published by other authors who used either a different radioisotope or a different labeling method.

Humans↗
PubMed1982

The correlation of adenosine deaminase and purine nucleoside phosphorylase activities in human lymphocytes subpopulations and in various lymphoid malignancies.

Adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) were measured in normal human and in malignant lymphoid cells. Thymocytes had high ADA activity (21.2 +/- 6.8 10(3) nM/h/mg) and low PNP activity (1.2 +/- 0.6), whereas T peripheral blood lymphocytes (PBL) had low ADA activity (1.20 +/- 0.22) and high PNP activity (2.8 +/- 1.3). Moreover cortico-thymocytes had higher ADA and lower PNP levels than medullary thymocytes. A linear correlation was observed between ADA and PNP activities in both thymocytes and T-PBL. Cells from 13 patients with T acute lymphoblastic leukemia (ALL) and 10 patients with T lymphoblastic lymphoma (LL) had very high levels of ADA (respectively 13.0 +/- 5.4 and 22.8 +/- 14) and low levels of PNP (respectively 1.9 +/- 0.8 and 2.5 +/- 1.4). However no clear relationship appeared between subgroups of these T-cell malignancies defined by their patterns of surface antigens, revealed by reactivity with monoclonal antibodies, and ADA and PNP levels, and there was no correlation between the two enzymes. In contrast, cells from 31 patients with HLA-DR+ common ALL had significantly low values of ADA as compared to cells from six patients with HLA-DR- common ALL and a linear correlation was observed between ADA and PNP in cells from children with non-T, non-B ALL. These results show that specific stages of T-cell development may be characterized by the relationships and the correlation between the two enzymes and suggest that T-ALL and T-LL appear to be the group of lymphoid malignancies with a high degree of incoordination between ADA and PNP activities.

Adenosine Deaminase↗
PubMed1982

Correlation between active E-rosettes and antigens defined on peripheral lymphocytes by OKT 4 and OKT 8 monoclonal antibodies.

A relationship has been sought between the classical marker, active E-rosette and the surface antigens of T-lymphocytes, defined by OKT 4 and 8 monoclonal antigens, in the peripheral blood of normal human people. It was found that no significant correlation existed in the case of OKT 4 antigen; conversely the OKT 8-positive cells were significantly enriched after E-rosette-forming cell isolation (about 2.5 times in comparison with the negatively selected cells). In this latter case, some partial correlation could exist between SRBC-high affinity of T-lymphocytes and the subsets defined by OKT 8 antigen.

Antibodies, Monoclonal↗
PubMed1982

Disposition and metabolism in 1-(2-chloroethyl)-3-(2',3',4'-tri-o-acetyl, ribopyranosyl)-1-nitrosourea in rats.

The antineoplastic activity in animals of 1-(2-chloroethyl)-3-(2',3',4'-tri-O-acetyl, ribopyranosyl)-1-nitrosourea (RPCNU) has been widely demonstrated. The present study deals with the disposition and the metabolism of three 14C-labeled species of RPCNU. The chemical plasma half-life of the drug was less than 5 min. Within the first min after injections, most of the radioactivity derived from ethyl-14C groups were recovered as volatile products. Among these, 2-chloroethanol was identified as a main component. Analysis of labeled species in urine after administration of [ethyl-14C]RPCNU showed that thiodiacetic acid and its sulfoxide were major metabolites of RPCNU (62% of the urinary radioactivity). Traces of N-acetylcarboxymethyl- and N-acetylhydroxyethylcysteine) were also detected. The only labeled species concentrating in particular tissues was that carrying the chloroethyl moiety. Uptake to high levels of [ethyl-14C]RPCNU did occur in liver, kidney, pancreas, thymus, and Harder's gland.

Acetylcysteine↗
PubMed1981

Parenteral intravenous nutrition (PIVN) as an adjunct to chemotherapy in small cell anaplastic lung carcinoma.

A randomized trial was initiated to compare the effects of PIVN-associated chemotherapy (adriamycin, vincristine, VP16-213 and cyclophosphamide) versus as chemotherapy control group in patients with small-cell lung neoplasias. The results obtained are preliminary. The test group included ten patients whereas nine were followed in the control group. PIVN was scheduled each day the patient underwent chemotherapy. Each patient received 1550 kcal/day, which included 10% glucose, 20% lipids, and amino acids which may or may not be mixed in the same infusion bottle. The results show three PIVN patients presently in complete remission at the end of three courses of treatment compared to two over the same time period in the chemotherapy control group. Of all patients who can be evaluated at this time, five out of six PIVN patients are in complete remission compared to four out of five in the control group. There was no significant difference in either general health or side effects, such as nausea and vomiting. The median length of time for which a low white cell or platelet count was noted was the same for both groups.

Adult↗
PubMed1981

Thymoma with hypersecretion of thymic hormone.

A 78-yr-old patient presented with a malignant thymoma with a predominance of epithelial cells. Lymphocyte markers (E rosettes, T-cell-specific xenoantigen and surface Ig) and electrophoretic studies showed that more than 95% of the peripheral blood lymphocytes were T cells. High levels of circulating thymic factor were repeatedly found before treatment (irradiation and chemotherapy). It is suggested that inappropriate hypersecretion of thymic hormone is responsible or can contribute to the immunological abnormalities found in this patient.

Aged↗
PubMed1980

Comparative physico-chemical properties, biological effects, and disposition in mice of four nitrogen mustards.

Chlorambucil, phenyl acetic mustard, melphalan and mitoclomine are aromatic nitrogen mustard derivatives. These drugs show a fairly wide range of chemical reactivity and lipophilicity. In the series presently investigated, the more hydrophilic compounds (melphalan and phenyl acetic mustard) are the more toxic to mice and also the more active against Moloney sarcoma implanted IP in mice. No clear relation could be shown between the alkylating activity and the biological efficiency. All the compounds induce changes in DNA synthesis with differences between the timing of alterations and recovery. Nevertheless, return to pretreatment levels of thymidine incorporation is more rapid in the bone marrow and intestinal mucosa following administration of the drugs, than in tumor cells. The 14C-ethyl labeled compounds was used to investigate the part of the carrying structure in their disposition in mice.

1-Naphthylamine↗
PubMed1980

Electrophoretic mobility of peripheral non-B human Fc gamma-receptors bearing lymphocytes.

The electrophoretic mobilities of separated "null" lymphocytes and of null and T cells bearing receptors for the fragment of immunoglobulins (Fc) portion of IgG have been studied in normal human blood. The data have been compared with those of other circulating subsets and with more conventional marker techniques. A large proportion of B cells was removed by nylon wool adherence. Further purification of the effluent cells separated 3 non-B populations using the property of sheep's red blood cells to form 2 types of rosettes with T cells on the basis of their relative affinity: "active" rosettes, and low affinity E-rosettes. A population of "null" cells was obtained which was effluent of the nylon wool column and non rosette-forming cells with SRBC (E-RFC). The average purity of this population was 85%; it was found to contain an increased proportion of rosette-forming cells with IgG coated erythrocytes (EA-IgG RFC) (41.3 +/- 10.4% vs. 11.9 +/- 3.8% in the total population) and exhibited high spontaneous incorporation of thymidine but low response to mitogens. The "null" cell population and its erythrocyte-antibody complex-rosette forming cells (EA-RFC) exhibited a defined electrophoretic mobility, centered between 1.05 and 1.15 micrometer. sec-1. v-1. cm in NaCl 0.145 M. The T populations, defined as ERFC, possessed different electrophoretic mobilities, and contained different proportions of Fc gamma receptor-bearing cells. Possessing an e. m. generally greater than 1.15 micrometer. sec-1. v-1. cm., high affinity "active" rosettes did not appear to contain EA-RFC, while the low affinity ERFC contained 18% (8 to 33) EA (IgG) RFC, and had an e.m. comprised between 1.00 and 1.15 micrometer. sec-1. v-1. cm. The presence of antibody-dependent cellular cytotoxicity was found to correlate with EA-RFC: mainly in EA-RFC of the "null" cells, but also to a lesser extent in EA-RFC of the low affinity ERFC. In normal human blood, these non-B Fc gamma receptor bearing cells appeared to possess a comparable electrophoretic mobility centered between 1.05 and 1.15 micrometer. sec-1. v-1. cm. in the "null" and low affinity ERFC subsets.

Adult↗
PubMed1980

Disposition of the carcinostatic agent 1-(2-chloroethyl)-3-[1'-(5'-p-nitrobenzoyl-2',3'-isopropylidene)-alpha,beta-d-ribofuranosyl]-1-nitrosourea in animals.

The disposition of 1-(2-chloroethyl)-3-[1'(5'-p-nitrobenzoyl-2',3'-isopropylidene)-alpha,beta-D-ribofuranosyl]-1-nitrosourea (RFCNU) was investigated in animals following i.p. administration (35 micromol/kg) of the drug labeled with 14C in three different positions. The appearance and disappearance kinetics of the label in blood and plasma were strongly dependent upon the labeled species administered to animals. Protein binding of [carboxyl-14C]- and [carbonyl-14C]RFCNU greatly prolonged the blood and plasma half-life of these two labeled species. No intact RFCNU was found when rat plasma samples were analyzed using high-performance liquid chromatography, indicating the very short half-life of this compound. Most of the dose was recovered in the urine after administration of the carboxyl-14C and ethyl-14C species and in the expired air as 14CO2 after administration of the carbonyl-14C species. Except for the liver and kidney, no specific localization of the radioactivity was found when animals were given [carboxyl-14C]- or [carbonyl-14C]RFCNU. However, tissue distribution studies showed a marked specificity of the species carrying the ethyl-14C moiety for the liver, kidney, pancreas, and thymus, but not for the brain.

Animals↗
PubMed1979

Peripheral lymphocytes changes in the anamnestic response to tetanus toxoid challenge.

Few data are available on the blood lymphocyte response to revaccination in man. The anamnestic response to tetanus toxoid challenge was evaluated by a variety of techniques during the first week after revaccination. Out of twenty subjects used, eight were evaluated before and 5 days after the injections (days 1--8). Analytical cell electrophoresis showed important variation in the B and two T lymphocyte populations. The B cell percentages, assessed by EAC-rosettes and electrophoretic mobility, were found to decrease by days 2 and 3, and return to former levels by day 8, when a rise in specific antibodies was detected. A similar response was found in the T1 population generally considered to be composed of low affinity E-rosette-forming cells. Conversely, a significant increase (50--100%) in circulating T2 lymphocytes (active rosette-forming cells) was found by days 2 and 3, followed by a rapid decrease of these 'differenciated' cells. The increase in the T2 lymphocytes appeared earlier in skin test positive subjects. These changes were correlated with E-rosettes, mitogen stimulation, peripheral leucocyte migration inhibition and transformation in the presence of the antigen. EA-IgG rosettes and ADCC varied similarly. These results may indicate a significant non-specific cell mobilization following revaccination.

Antibody-Dependent Cell Cytotoxicity↗