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Biomedical subjects

G Sebahoun

Publications and source records attributed to G Sebahoun.

At least 19 recordsLinked to original sources
PubMed1992

Modulation of normal human erythropoietic progenitor cells in long-term liquid cultures after HIV-1 infection.

Long-term bone marrow cultures (LTBMC) have been infected by two isolates of human immunodeficiency virus type 1 (HIV-1) (HIV-1 LAV and HIV-1 NDK) at multiplicities of infection ranging from 10(2) to 2.10(6) tissue culture infectious units (TCIU) per 10(6) bone marrow mononuclear cells (BMMNC). These infected cells are nonproducer cells and the viruses can be rescued by coculture with peripheral blood lymphocytes, cord blood lymphocytes, or BMMNC and not by the CEM cell line. HIV-1 clearly is not cytopathic for these cells. Following production and growth of erythroid burst-forming units (BFU-E) and erythroid colony-forming units (CFU-E) for at least 6 weeks after infection with HIV-1 NDK, colony assays displayed a 50% inhibition of BFU-E production during 3 weeks of LTBMC. This was followed by a stimulation phase. On the contrary, HIV-1 LAV induces a 150% stimulation of BFU-E production, followed by 50% inhibition. Production of CFU-E was inhibited by 80-100% with the two isolates of HIV-1 after four weeks of LTBMC. Stimulatory and inhibitory activities were recovered from supernatants of infected LTBMC and lymphoid CEM cell lines, suggesting that HIV-1 induces release of a humoral factor responsible for disruption of hemopoietic progenitor cell production in vitro and consequently for hematologic abnormalities in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Acute monocytic leukemia: prevalent cutaneous lesions. Two cases.

The authors report two cases of acute myeloid leukemia with prevalent cutaneous lesions. The positivity of granulo-monocytic antibodies and the exclusive cutaneous site of the lesions drove them previously to the diagnosis of histiocytic sarcoma. These cases stress the problem of the immunological identification of cutaneous lymphomas of "histiocytic" type.

Aged↗
PubMed1991

Histological evolution of peripheral T-cell lymphomas. Study of six cases.

The authors report 6 cases of histological transformation in peripheral T-cell lymphomas of low grade of malignancy. The transformation occurs in 75% of the cases, in extra-nodal sites and corresponds to a monomorphic of pleiomorphic large cell type. There is no discordance in the immunologic results between the two phases. The transformation seems to occur earlier than in B lymphomas, with a relative frequency of hematological manifestations and no therapeutic response.

Aged↗
PubMed1979

[The association of a myeloma and Paget's disease (author's transl)].

The coexistence of a myeloma and Paget's disease in the same patient is only rarely reported in the published literature. The frequency of such an association was studied when reviewing 3 cases observed by the authors: an IgG myeloma discovered following a spasmodic paraplegia in a patient with Paget's disease; a patient who was found to have a myeloma, a polynuclear neutrophil leukemia, and Paget's disease; and an IgG myeloma in a patient with probable localized Paget's disease. The incidence of the association myeloma-Paget's disease is much lower than that of sarcomatous degeneration. It should be determined precisely, however, as our future conception of the reciprocal relationship between the two diseases is greatly dependent on this information. Furthermore, the very few cases reported, and their lack of homogenicity, are the reasons why most authors feel that the association of myeloma and Paget's disease as pure coincidence. Many new cases, however, have been recently reported. The problem of the significance of the association of Paget's disease and macroglobulinemia or other monoclonal gammapathies has still to be solved.

Aged↗
PubMed1978

Histamine release reaction of basophils in chronic granulocytic leukaemia. Induction by heterologous anti-immunoglobulin E, concanavaline A, and phytohaemagglutinin; effect of heavy water.

Basophils possess membrane bound IgE molecules, and immunological activation leads to a secretory process with cell degranulation and histamine release. Heterologous anti IgE, concanavaline A, and phytohaemagglutinin are potent non-cytotoxic releasing agents. They operate by a mechanism similar to that of immunological activation. Heavy water is not a histamine releasing inducer but it increases histamine release of the cells. We studied the histamine release reaction of leukaemic basophils in 10 patients and found a physiological response such as that previously reported with normal human basophils.

Antibodies, Anti-Idiotypic↗
PubMedDate not supplied

[Congenital type II dyserythropoiesis].

The authors report a case of congenital dyserythropoieses, type II, the diagnosis of which was made in a young 15 year old girl with anemia, sub-clinical jaundice and splenomegaly. The following three criteria were found: erythroblastic hyperplasia with a high percentage of binuclear cells, a double peripheral red cell membrane under the electron microscope and a positive Ham-Dacle test. An isotopic study showed a double process or erythropoiesis which was inefficacious and peripheral hemolysis. In connection with this case, the authors then recall the main characteristics of the three types of congenital dyserythropoiesis. The origin and consequences of the peripheral membrane excess of the erythroblasts characteristic of type II are then discussed.

Adolescent↗