Biomedical subjects

D Blaise

Publications and source records attributed to D Blaise.

189 records · Page 11Linked to original sources

PubMed1977

"Active" one-carbon generation in Saccharomyces cerevisiae.

A new mutation introducing a one-carbon requirement (e.g., formate) for the glycine-supplemented growth of a serine-glycine auxotroph (ser1) was correlated with a lack of glycine decarboxylase activity. The presence of oxalate decarboxylase activity or glyoxylate decarboxylase activity did not overcome the one-carbon requirement. Another mutation characterized by the absence of oxalate decarboxylase activity did not introduce a one-carbon requirement. The presence and physiological significance of glycine decarboxylase activity in Saccharomyces are thus inferred.

Acetates↗

PubMedDate not supplied

Psychosocial aspects of haematopoietic stem cell donation for allogeneic transplantation: how family donors cope with this experience.

Peripheral blood stem cell (PBSC) allogeneic transplantation is an innovative medical procedure which has many advantages in comparison with bone marrow (BM) transplantation, but it involves administering haematopoietic growth factors (HGFs) to donors, the long-term physiological effects of which have not yet been established. The main aim of the present study was to analyse how family PBSC donors cope when confronted with this particular risk context. In addition to data collected on the personal and social aspects of the donors' experience, questionnaires were used to measure their quality of life (pain and anxiety) before, during and after donation, and they were subsequently interviewed in depth by a psychologist. Twenty-two donors participated in this study. They did not all react to the experience of blood cell donation in the same way, in terms of their own personal feelings, attitudes towards the donation, their relationships with the other members of the family, and their awareness of the risk involved.

Adaptation, Psychological↗

PubMedDate not supplied

Survey of early disapearance of BCR/ABL fusion transcript after allogeneic or autologous stem cell transplantation for chronic myelogenous leukemia.

The detection of BCR-ABL specific RNA by RT-PCR has been shown to predict relapse when positive 6 months after allogeneic stem cell transplantation (SCT) for chronic myelogenous leukemia (CML). In the present study, the focus was on evaluation of residual disease during the first weeks following SCT. In this study, 177 blood or marrow samples were obtained from 33 patients who received allogeneic (20 patients) or autologous (13 patients) SCT on day 0, day 30 and every 3 months for 1 year. T-cell depletion (TCD) was performed in 4 cases. On day 0 (day of graft infusion), 10/30 evaluable patients had negative RT-PCR (33%) regardless of pretransplant characteristics. On day 30, 14/18 patients (77%) from the allogeneic group had negative RT-PCR versus 0% in the autologous group. 2/4 patients who received TCD allogeneic grafts had day 30-positive PCR. Five patients in the allogeneic group had at least one positive RT-PCR sample between day 30 and day 90: 3 of them subsequently relapsed suggesting possible correlation between early positivity and relapse. Our results show that disappearance of MRD can be achieved within 3 months after transplantation in the majority of patients treated with allogeneic but not after autologous SCT. This suggests that the GVL effect might be operational early during the first weeks following transplantation.

Adult↗

PubMedDate not supplied

High-dose chemotherapy with hematopoietic stem cell support in patients with advanced epithelial ovarian cancer: analysis of 67 patients treated in a single institution.

BACKGROUND: Advanced ovarian carcinoma is a chemosensitive tumor, but its prognosis is poor with 20 to 30% 5-year survival using conventional therapy. Increasing doses of chemotherapy might improve the prognosis because of the dose-effect. MATERIALS AND METHODS: Between 1980 and 1994 at Institut Paoli-Calmettes, 67 patients with advanced ovarian cancer were treated with different alkylating agents-based regimens of high dose chemotherapy (HDC) and hematopoietic stem cell support (HSCS). The population was divided in 2 groups: a salvage group (n = 30) including initial conventional chemotherapy-refractory patients, and a consolidation group (n = 37) including patients whose disease was sensitive to classical first-line chemotherapy after debulking surgery. RESULTS: Toxicity was essentially hematological (severe aplasia) and digestive (mucositis). Four toxic deaths occurred related to infection during immunosuppression. In the salvage group, 9 out of 22 evaluable patients responded (41%), but the duration of responses was short (median range of 6 months) and the 2-year overall survival rate was 13%. In the consolidation group, 17 patients are still alive, 12 with progression with a median follow-up of 63 months. The 5-year disease-free survival rate was 32% while the 5-year overall survival rate was 46%. CONCLUSIONS: Toxicity of HDC with HSCS is acceptable for poor-prognosis patients. In the long term, this therapy is not beneficial for chemotherapy refractory patients, despite objective response rates better than the conventional treatment, confirming the dose-effect for alkylating agents in ovarian cancer. On the other hand, the results seem better than classical therapy in case of chemosensitive disease and should be confirmed prospectively in a larger cohort of patients.

Antineoplastic Agents, Alkylating↗

PubMedDate not supplied

Pilot study of immunotherapy with interleukin-2 after autologous stem cell transplantation in advanced breast cancers.

Median survival for advanced breast cancer does not exceed 2 years. Immunotherapy following Hihg Dose Chemotherapy (HDC) and autologous stem cell transplantation (ASCT) is a procedure that could hypothetically decrease relapse rate. The mechanism implicated is induction of immune modulation and a possible Graft Versus Tumor effect (GVHT). Tolerance and feasibility of rIL-2 administered after HDC with ASCT was analyzed in twenty one advanced breast cancer patients. The patients were treated either with intra-venous high-dose rIL-2 (9 patients) or subcutaneous low dose (12 patients). With intra-venous high-dose rIL-2, 50% of the scheduled dose was administered and 100% of the scheduled dose was administered at a lower dose in the subcutaneous route. rIL-2 was administered safely after HDC and ASCT, particularly in the subcutaneous low dose arm. However no clinical beneficial effect was documented for these advanced heavily pretreated breast cancers. Immune modulation with rIL-2 earlier requires further investigation.

Adult↗

PubMedDate not supplied

Interleukin-2 induces chemotactic deficiency in patients with onco hematologic malignancies and autologous bone marrow transplantation.

Unusual gram positive bacteremia has been reported in non granulopenic patients receiving recombinant human interleukin-2 (IL-2) suggesting a beneficial effect of anti gram positive prophylaxis in such patients. We report here studies on granulocyte functions examined during the course of high dose IL-2 therapy (16 to 24 million IU/m2/days for 11 to 18 days) administered during a period of 35 days in 14 patients including 4 solid tumors, 5 chronic myeloid leukemias, 4 recipients of autologous bone marrow transplant (ABMT) and 1 recipient of syngeneic bone marrow transplant. Neutrophils functions were studied before IL-2 administration (d 0), after the first cycle (d 8) and after the third cycle (d 36). Nylon fiber adherence, superoxide production, random migration, phagocytosis, nitroblue tetrazolium reduction, lysozyme and elastase release were not impaired significantly throughout therapy. However N-Formyl-Methionyl-Leucyl-Phenylalanine (FMLP) stimulated chemotaxis of granulocytes, normal before therapy, was significantly impaired as early at d 8 and severely inhibited at d 36 (p less than 0.001). Three septicemia, one corynebacteria parvum septicemia and two gram-negative septicemia despite normal neutrophil counts and oxacillin or Penicillin G plus Pefloxacin prophylaxis, occurred among the 14 patients studied. Although neutrophil functions were not more depressed in transplanted patients than in the other non transplanted patients, special attention should be paid to such patients in whom delayed immune reconstitution could increase the risk of sepsis.

Adult↗

PubMedDate not supplied

Recombinant interleukin-2 (rIL-2) after autologous bone marrow transplantation (BMT): a pilot study in 19 patients.

In vivo use of rIL-2 autologous BMT may be the means of reproducing a kind of "adoptive immunotherapy" from grafted cells after allogeneic BMT. This approach may enhance the spontaneous generation of cytotoxic T-cells and NK cells which are presumably involved in this immunotherapy. Potential risks of such an approach would be to increase the usual toxicity of rIL-2 and to jeopardize the hemopoietic reconstitution. To determine the feasibility of this approach we have treated 19 poor prognosis patients with a succession of autologous BMT followed 78 +/- 12 days later by a continuous infusion of rIL-2. Eighteen million international units (IU) per m2 per day of Proleukine (CETUS, Amsterdam, The Netherlands) were administrated over 6 or 12 days. No patient died of the procedure. Clinical toxicity related to rIL-2 was not increased. Hemopoietic toxicity, significant both for platelets and granulocytes, was transient. Immune stimulation was dramatic for lymphocytes and subpopulations (CD3+ and NK cells) and for cytolytic functions (NK and LAK activity). This trial establishes the feasibility of administration of high doses of rIL-2, 2 months after autologous BMT. In this setting a 6 day period of continuous infusion of 18 million per m2 per day of Proleukine appears to be a regularly tolerable dosage conducting to a major immune activation and invites further studies to determine the clinical impact of such an approach.

Adjuvants, Immunologic↗

PubMedDate not supplied

[Veno-occlusive disease of the liver after bone marrow transplantation. Report of the symposium Autograft in France and the group of study of bone marrow transplantation. France Auto-Greffe et le Groupe d'Etude de la Greffe de Moelle osseuse].

Hepatic veno-occlusive disease is a frequent complication after high-dose chemo- or radiotherapy after bone marrow transplantation and is a major cause of mortality. During the 3 weeks following transplantation, acute major hepatic vascularization is observed together with portal hypertension and weight gain, ascitis and oedema of the lower limbs due to non-thrombotic obstruction of the centrilobular hepatic veins. This report summarizes the observations presented at a French symposium of France Autogreffe and Groupe d'Etude de la Greffe de Moelle osseuse. Different pathogenic processes are implicated including endothelial mechanisms due to toxic factor related to graft preparations and immunosuppressor treatments (methotrexate, cyclosporin), physical factors related to irradiation, immunological factors related to the expression of class II antigens on endothelial cells and viral factors, in particular cytomegalovirus infection. The incidence of veno-occlusive disease varies greatly from one series to another. Two French groups reported 5 and 3 cases among 1991 and 253 autologous grafts respectively (1.2 and 2.3%) while the Seattle group observed 53% among 355 consecutive grafts, although the same clinical criteria were used. Histological criteria include fibrosis around a non-thrombotic occlusion of the centrilobular veins, cytolysis and congestion of the sinuses. Other methods for diagnosis include transjugular biopsy, the suprahepatic pressure and imaging techniques. Prophylactic continuous infusion of low-dose heparin has been associated with a lower incidence. Trials using anti-tumour necrosis drugs and prostaglandin E1 have also been undertaken and show possible effects towards decreasing prevalence.(ABSTRACT TRUNCATED AT 250 WORDS)

Alprostadil↗

PubMedDate not supplied

rIL-2 in metastatic soft tissue sarcomas refractory to chemotherapy: response and enhancement of further chemosensitivity.

Chemotherapy (CT) in advanced and metastatic soft tissue sarcoma (STS) has a reported response rate of 17 to 30%, with a median survival of 30 months. Experimental and clinical studies have demonstrated some response with high-dose intravenous recombinant Interleukin-2 (r-IL2). We report a retrospective analysis of twelve patients with metastatic or locally evolutive STS who received high-dose rIL-2 immunotherapy: all patients were pre-treated with CT and were non responsive. All of these patients developed usual severe toxicity. One patient achieved a partial response with rIL-2 with more than 75% regression of lung metastases. All patients received CT post rIL-2 and 2 of them achieved a further response: 1 of them had a complete response (CR), and one had a partial response (PR). These results suggest that rIL-2 has a relatively low efficacy in patients with STS but that some of these patients can be, after rIL-2, responders to CT despite previous resistance.

Adult↗