J Tavares de Castro

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We describe a method for electron microscopy that combines myeloperoxidase or acid phosphatase cytochemistry with the labelling of cell surface antigens with monoclonal antibodies and colloidal gold. This technique was tested in samples of normal mononuclear cells, leukaemic T cells with a mature or immature phenotype and an acute myeloid leukaemia. This(More)
We carried out cytogenetic analysis in 23 patients with Ph-positive chronic granulocytic leukemia in blast crisis. In all cases the type of blast cell was characterized by cytochemistry, immunologic markers, and ultrastructural studies. Twelve cases were classified as myeloid transformation, six as lymphoid, two as mixed (lymphoid and myeloid), and two were(More)
A systematic analysis of the blast cell population was carried out on samples from 50 patients suffering from blast transformation of chronic granulocytic leukaemia (CGL) (31) and of myelofibrosis (4), acute myelofibrosis (AM) (11) and undifferentiated acute leukaemia (4). Transmission electron microscopy (TEM), used in 41 samples, included: morphology and(More)
The expression of two membrane antigens identified by the monoclonal antibodies (McAb) My9 and 3C5 has been investigated in cells from 80 acute leukemias. My9 was positive in the blasts of 33 out of the 38 (87 per cent) cases of acute myeloid leukemia (AML) tested, regardless of FAB subtype, and in 13 of 18 (72 per cent) cases of chronic granulocytic(More)
We have studied, by ultrastructural morphology and immunocytochemistry, the alterations that occur in cells from the HL60 leukaemia cell line and from patients with CGL following incubation in vitro with 1,25(OH)2D3 for 2-5 days. The main morphological changes observed were in the nuclear shape, the development of autophagic vacuoles and the appearance of a(More)
The combination of morphological, cytochemical and immunological methods has resulted in a reproducible and more objective classification of AL. Several of the AML-FAB subtypes (M2, M3 and M5) correlate with specific chromosome abnormalities and are associated with distinct clinical and laboratory features. The classification of ALL based on morphology (FAB(More)
A cytogenetic analysis was carried out on bone marrow cells from 11 patients who presented with hypereosinophilia and the clinical features of the idiopathic hypereosinophilic syndrome. One of these patients was found to have trisomy 8 affecting the myeloid series, including eosinophils. In this patient, marrow eosinophils also showed asynchrony of(More)
A method for the simultaneous labelling of terminal deoxynucleotidyl transferase (TdT) and membrane antigens is described. TdT is visualised in the cell nucleus with the peroxidase-antiperoxidase (PAP) method, and the immunogold method is used in combination with monoclonal antibodies against membrane antigens. The morphology of the labelled cells is well(More)