Search PubMed⌕ Search

Biomedical subjects

G Vezon

Publications and source records attributed to G Vezon.

53 records · Page 3Linked to original sources
PubMed1988

[Collection of blood stem cells and therapeutic applications].

Peripheral blood stem cells were collected from 50 patients with different hematological malignancies. Leukaphereses (n = 263) were performed during the marrow regeneration phase following different types of chemotherapy. The mean number of CFU-GM collected per leukapheresis was 486 x 10(4), highest levels of CFU-GM being obtained in patients who received the most intensive chemotherapy and who had not been treated previously. Twenty-five patients underwent autologous blood stem cell transplantation. Hemopoietic recovery was complete and prompt in 24 patients. Only one patient had no megakaryocytic engraftment. These findings indicate that peripheral blood stem cells may be used for autologous transplantation in leukemic patients.

Adolescent↗
PubMed1987

Characterization of a murine monoclonal antibody specific for the human P1 blood group antigen.

Four monoclonal antibodies (MAbs) directed against the P1 blood group antigen were produced by hybridomas obtained from mouse immunized with turtle-dove avomucoid. One of the MAb (154 IX B6) selected as a blood typing reagent agglutinated native P1 and Pk1 red cells with a high titer but was inactive against native P2, Pk2 and p erythrocytes. After papain treatment the reactivity towards P1 and Pk1 erythrocytes was enhanced whereas p erythrocytes remained unreactive. A weak cross-reactivity of the MAb with the Pk antigen was suspected since enzyme-treated Pk2 erythrocytes became significantly agglutinated. Further analysis of the antibody specificity was established by binding studies using neutral glycolipids prepared from P1 and P2 erythrocytes, affinity immunoabsorbents carrying known oligosaccharide structures and hapten inhibition with synthetic oligosaccharides. The MAb bound weakly to the Gal alpha 1-4Gal structure common to P1 and Pk antigens but had a marked preference for the P1 determinant (Gal alpha 1-4 Gal beta 1-4 GlcNAc) and the binding was abolished by prior treatment of oligosaccharide antigens by alpha(not beta)-galactosidase, which supports evidence that a terminal alpha-galactose residue is involved in the blood group P1 and Pk specificities. The MAb has a slightly broader specificity than the human anti-P1 counterpart but can be used safely for routine blood typing.

Animals↗
PubMed1986

Technical aspects of different donor plasmapheresis systems and biological results obtained in collected plasma.

Four plasmapheresis systems were comparatively studied: a centrifugation system (Haemonetics Model 50) and three filtration ones (Dideco BT 810, Organon Teknika PLASMAPUR and HemaScience Autopheresis Plasmacell). For each separator we studied the technical conditions for plasma separation, the biological characteristics of the collected plasma and the in vitro recovery of factor VIIc after preparation of cryoprecipitates. Concerning the plasma extraction rate, the HemaScience apparatus was the most efficient but values were quite similar to those obtained with the Organon Teknika machine. Contaminating cells were only found in plasma separated with the Haemonetics. Total protein and immunoglobulin levels were higher in plasma collected with the Haemonetics and HaemaScience systems. Factor VIIIc activity was comparable in plasma separated by filtration or by centrifugation while fibrinopeptide A levels were higher in plasma collected by Haemonetics. Whatever the machine, no statistical difference was observed when in vitro recovery of factor VIII was studied.

Blood Donors↗
PubMed1986

Successful autologous transplantation with peripheral blood hemopoietic cells in a patient with acute leukemia.

One patient with acute nonlymphocytic leukemia (ANLL) in remission was given intensive chemotherapy (DAT regimen) as late intensification treatment. Seven leukaphereses were performed during the period of marrow recovery following aplasia induced by the DAT regimen. High numbers of nucleated cells (7.8 X 10(8)/kg) and granulocyte-macrophage precursors (9.5 X 10(4)/kg) were collected and then cryopreserved and stored in liquid nitrogen. When he relapsed, the patient was treated with etoposide (600 mg/m2), cyclophosphamide (120 mg/kg), and total body irradiation (1000 rad), followed by the transfusion of thawed autologous leukocytes. The time to reach 0.5 X 10(9) granulocytes/liter and 50 X 10(9) platelets/liter was 16 and 35 days, respectively. This observation demonstrates that circulating hemopoietic stem cells are capable of complete hemopoietic reconstitution after marrow-ablative therapy with supralethal doses of chemoradiotherapy.

Adolescent↗
PubMed1986

[Production and characterization of monoclonal antibodies with P1 specificity].

Four monoclonal antibodies, with P1 specificity were obtained after fusion of myeloma cells and spleen cells from mice immunized with turtle dove ovomucoid. Immediately after the fusion, the culture supernatants were studied for specificity with panels of erythrocytes and red blood cells sharing rare phenotypes (P1K, P2K, p) in the P system. After cloning, four monoclonal antibodies were produced, these antibodies strongly agglutinate P1 red blood cells, specially when they are used with 3% of dextran or with a 350 mmol/l concentration of sodium.

Animals↗
PubMed1984

[Acute transformation of chronic myeloid leukemia: disappearance of the Philadelphia chromosome after autograft].

Two patients with chronic granulocytic leukemia (C.G.L.) undergoing transformation were treated by high dose chemotherapy and total body irradiation followed by autografting of hematopoietic stem cells collected and cryo-preserved at the time of diagnosis. Recovery of hematopoiesis was characterized by disappearance of the Philadelphia chromosome in most metaphases. A new approach of the management of C.G.L. is discussed.

Adult↗
PubMed1982

[Comparison of platelets frozen with different cryoprotective agents].

A comparative study was performed on platelets frozen with dimethyl-sulfoxide (D.M.S.O.), glycérol and dimethyl-acetamide (D.M.A.C.). The results of tests realized in vitro (platelet yields after thawing platelet aggregation, hypotonic stress, release of enzymes and ultrastructure), and in vivo (life span and recoveries after transfusion) have clearly shown that D.M.S.O. is the best cryoprotective agent. The results obtained with glycerol were less interesting and more clinical data are needed in order to study the hemostatic effectiveness of platelets preserved with this agent. Dimethyl-acetamide gave the worse results and in our opinion, must not be used for the cryopreservation of platelets.

Acetamides↗
PubMedDate not supplied

[Microsporum canis mycetoma of the scalp].

BACKGROUND: Mycetoma is a chronic subcutaneous tumefaction with presence of grains or granules. Etiological agents include bacteria or filamentous fungi. Mycetoma due to dermatophytes is uncommon, mainly occurring in Africa. To our knowledge, no case has been reported in the West Indies. Only two observations of Micosporum canis mycetoma in humans have been reported in the literature. We report a third case of mycetoma of the scalp caused by this fungus. CASE REPORT: A 22-year-old woman from Martinique, French West Indies, presented with an indolent tumefaction of the scalp evolving over five years. She had mental retardation due to congenital adrenal hyperplasia with 21-hydroxylase deficiency. The lesion was extracted surgically. Pathology and mycology examinations showed features of Microsporum canis mycetoma. Two months later, the scalp lesion recurred and the patient was treated with griseofulvin after surgical extraction. DISCUSSION: Mycetoma due to dermatophytes is very uncommon, mainly observed on the scalp and nape of the neck. A history of a skin lesion is frequent, leading to transcutaneous penetration of the fungus and mycetoma formation. Several dermatophyte species have been identified as causal agents (Microsporum ferrugineum, Trichophyton rubrum, Trichophyton verrucosum, Trichophyton mentagrophytes, Microsporum audouinii, Microsporum langeronii). Microsporum canis is rarely demonstrated in humans: two cases in children in Africa and Australia. Our observation was similar to the two cases in the literature: indolent and mobile tumefaction of the scalp, in a child or young adult, suggestive of lipoma or epidermal cyst, with excision leading to diagnosis. Association with tinea capitis and skin or nail involvement can also be observed.

Adult↗
PubMedDate not supplied

[Panniculitis induced by MINE chemotherapy].

BACKGROUND: Drug-induced panniculitis are uncommon. We report the second case of panniculitis induced by MINE chemotherapy. CASE REPORT: A 31-year-old woman with relapsed Hodgkin disease was treated with MINE cytostatic regimen. Multiple erythematous and painful nodules of panniculitis developed on her chest, abdomen and thighs fifteen days after the beginning of drug administration with a second flare up after second administration of the same drugs. The eruption cleared slowly after treatment withdrawal. DISCUSSION: To our knowledge, our case is the second reported case of panniculitis induced by MINE chemotherapy. Drug-induced panniculitis is uncommon and usually induced by steroid treatment. Some cases of panniculitis induced by atenolol, potassium bromide, apomorphine, interferon alpha and interleukin 2 have been described. Few cutaneous adverse effects are reported with MINE chemotherapy: rash, erythema and swelling of extremities. A case of inflammatory swelling of thighs with hemorrhagic panniculitis due to this treatment has been described recently.

Adult↗
PubMedDate not supplied

[Acute myelogenous leukaemia: prognostic value of infectious complications observed during the induction treatment (author's transl)].

The prognostic value of infectious complications occurring during the induction treatment of acute myelogenous leukaemia is analysed and discussed. Eighty-eight patients were treated with the same chemotherapy. The early major infections (septicemia, pneumonia, ano-rectal abscesses) and on the other hand, the late infections (following the maximum agranulocytosis) are of a bad prognosis. During the second phase of chemotherapy-induced aplasia, the improvement of infection means usually a forthcoming complete remission while its persistence or its aggravation means usually a failure of the chemotherapy. At last, when the complete remission has been achieved, no peculiar feature of the infection is significantly correlated with the survival.

Adolescent↗