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Biomedical subjects

B Dreyfus

Publications and source records attributed to B Dreyfus.

At least 91 records · Page 5Linked to original sources

The blast crisis of chronic granulocytic leukaemia: megakaryoblastic nature of cells as revealed by the presence of platelet-peroxidase--a cytochemical ultrastructural study.

The origin of cells in the blast crisis of some cases of chronic granulocytic leukaemia (CGL) remains controversial. Difficulties arise from the lack of cytochemical characteristics of differentiation. This report concerns the nature of cells in the blast crisis of a case of CGL in which blast cells exhibited an undifferentiated or lymphoid appearance by light and electron microscopy. The majority (90%) of such cells contained a peroxidase in the endoplasmic reticulum distinct from myeloperoxidase. In addition, some micromegakaryocytes could be recognized among the peroxidase reactive cells, by the presence of typical granules and demarcation membranes. Since this peroxidase exhibited identical characteristics to that of normal megakaryocytic precursors, these blast cells could be identified as megakaryoblasts. These data emphasize the possible megakaryoblastic nature of cells occurring in other cases of CGL blast crisis.

Adult↗

Synthesis of a peroxidase activity by the cells of hairy cell leukemia: a study by ultrastructural cytochemistry.

The nature of cells present in the blood, marrow, and spleen of patients with hairy cell leukemia is largely debated. These cells have been tentatively categorized on the basis of either monocytic or lymphocytic markers, and the accumulating data points to the fact that they share some characteristics of both cell types. Although hairy cells are known to lack myeloperoxidase-positive granules, present in normal human monocytes, we investigated the possible presence of other peroxidase activities differing from the granule-bound myeloperoxidase. The study was carried out with several methods based on the incubation of fixed and unfixed cells in the presence of diaminobenzidine and hydrogen peroxide. A peroxidase activity was found in hairy cells, located always in the endoplasmic reticulum but not in the Golgi apparatus or in any granule. By its cytochemical characteristics it appears to be closely related to that of tissue macrophages, activated blood monocytes, and other nonlymphocytic hematopoietic cells. This peroxidase is not found in lymphocytes with B or T phenotypes.

Histocytochemistry↗

Electrophoretic and kinetic studies of human erythrocytes deficient in pyrimidine 5'-nucleotidase.

A new case of a defect in red cell pyrimidine 5'-nucleotide (P5N) activity was found in a large family from Guadeloupe in the West Indies. The propositus presented a characteristic hemolytic anemia with red cell basophilic stippling, an increased GSH level, and a shift of the peak in absorbance of nucleotide. The enzyme activity from the deficient red cells differed from that of the normal. The P5N activity of the deficient red cells was about 14% that of normal. The electrophoretic pattern of P5N activity of the deficient red cells was distinct from that of the control in terms of its Km and of the effects of pH on its maximum activity and heat stability. The significance of such differences is discussed.

Anemia, Hemolytic, Congenital↗

Structural and functional studies of hemoglobin J Cala-bria: beta64 (E8) Gly leads to Asp.

A hemoglobin of high electrophoretic mobility was detected in a French male suffering from an acute leukemia; this hemoglobin was also present in his family. The variant was unstable and possessed an abnormal beta chain, in which a glycyl residue in position 64 (E8) was replaced by an aspartyl residue. This variant constitutes a new case of Hb J Calabria. Since the substituted E8 residue is in close spatial contact with that at B6, it was of interest to compare the properties of Hb J Calabria with those of other hemoglobins bearing substitutions at the same site.

Adult↗

[The presence of an endogenous peroxidase activity in hairy cell leukemia cells].

Mononuclear cells from hairy cell leukemia have been studied in three cases by ultrastructural immunocytochemistry. Cells have fairly detectable surface immunoglobulins, without monoclonal distribution however. In addition these cells have a peroxidatic activity which is revealed in the perinuclear space and strands of endoplasmic reticulum.

Cytoplasm↗

[81 cases of Hodgkin's disease treated with extensive radiotherapy, including 65 with primary MOPP chemiotherapy (author's transl)].

Study 81 cases of Hodgkin's disease at stages I, II or III led to the following conclusions from a therapeutic standpoint (in relation to the apparent results obtained): The addition of chemotherapy on the form of three courses of MOPP before irradiation improved the results of the latter on the one hand and, principally, by reducing the number of failures and, secondly, by reducing the complications. The addition of chemoprophylaxis by MOPP in patients in complete remission as a result of initial treatment, involving an association of 3 courses of MOPP followed by radiotherapy, was not shown to be useful. A major factor in prognosis would to be the clinical and radiological situation after the first three courses of MOPP (in the context of combined MOPP and radiotherapy) since, despite the later radiotherapy, numerous failures were noted in the absence of remission after the three MOPP treatments, whilst failure rarely occurred under the opposite set of circumstances. This is important, since modest treatment would seem to suffice in patients reacting well to three initial MOPP treatments, whilst it is essential to reinforce it when this is not the case.

Drug Therapy, Combination↗

[Chemotherapy-radiotherapy association in the treatment of localized forms of Hodgkin's disease. Prognosis of polychemotherapy after three trials of M.O.P.P].

63 patients with Hodgkin disease of limited extent (I, II, III) are treated with two protocols: extended field irradiation versus chemotherapy (M.O.P.P.) + extended field irradiation. Three points are suggested by analysis of the results: 1) Advantage from the combination of chemotherapy-radiotherapy. 2) Resistance to chemotherapy frequent innodular sclerosis. 3) In patients treated with chemotherapy the reaction has a prognostic value: failure of treatment being seen only in patients who did not obtain a complete remission.

Drug Therapy, Combination↗