1/5. Suppressed expression of blood group B antigen and blood group galactosyltransferase in a preleukemic subject.The B antigen activity was severely diminished in a patient's RBCs at the preleukemic stage prior to chemo- or radiotherapy. The amount of H sites of the patient's RBC membranes was found to be comparable to that of O RBC membranes. The activity of alpha (1 2) fucosyltransferase (H enzyme) was not severely decreased in the patient's plasma and bone marrow. However, the activity of alpha (1 3) galactosyltransferase (B enzyme), which converts H substance to B substance, was drastically reduced in the patient's bone marrow. Thus, the diminished B antigen in the patient's RBCs was caused mainly by the blockage of conversion of the H substance to B substance. It is suggested that the viral oncogene linked to the ABO locus at q34 of chromosome No. 9 would occasionally suppress the expression of blood group A and B enzymes and A and B antigens.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/5. Monoclonal B-cell lymphocytosis in early childhood. A case report.A case is reported of a 12-year-old girl with a benign course of a lymphocytosis through years associated with splenomegaly. The lymphocytes simultaneously expressed a monoclonal B-cell phenotype of IgM-kappa and a mature T-antigen using the monoclonal OKT1 antibody. Due to her stable condition, no treatment was required. The immunological results suggest the possibility of an early childhood B-cell chronic lymphoid leukemia.- - - - - - - - - - ranking = 0.14285714285714keywords = antigen (Clic here for more details about this article) |
3/5. reticulocytosis, hypochromia, and microcytosis: an unusual presentation of the preleukemic syndrome.Two patients exhibiting a highly unusual preleukemic syndrome with marked reticulocytosis, hypochromia, and microcytosis are reported. This red cell phenotype has been investigated by means of HbF, HbA2, and i-antigen activity dosages, immunofluorescence labeling of F cells, reticulocyte survival, globin chain synthesis, and electron microscopy study. The marked reticulocytosis is explained by a delayed disappearance of the reticulum. serum iron is normal, and a thalassemic syndrome is excluded because of a balanced alpha/non-alpha globin chain synthesis. Electron microscopy studies are consistent with a defect in iron uptake by erythroid cells. All the hematologic data and investigations are similar to those observed for the Belgrade laboratory rat. It is hypothesized that the low expression of HbF and i-Ag associated with microcytosis are related to a prolongation of erythroid maturation as reflected by abnormal reticulocyte survival.- - - - - - - - - - ranking = 0.14285714285714keywords = antigen (Clic here for more details about this article) |
4/5. Acute myeloid leukemia with preceding systemic lupus erythematosus and autoimmune hemolytic anemia.A 10-year-old girl with systemic lupus erythematosus (SLE) and autoimmune hemolytic anemia developed acute leukemia 10 months after the diagnosis of SLE. Leukemic cells had both the myeloid character, as shown by peroxidase activity, and T-cell surface antigen. The SLE-like syndrome as a paraneoplastic syndrome is discussed.- - - - - - - - - - ranking = 0.14285714285714keywords = antigen (Clic here for more details about this article) |
5/5. Pathogenetic significance of "pure" monosomy 7 in myeloproliferative disorders. Analysis of 14 cases.monosomy 7 is frequent in acute myeloid leukaemia (AML) and in preleukaemic dysmyelopoietic syndromes but often it is not the only chromosome anomaly associated with these conditions. We report 14 patients with "pure" monosomy 7 and their clinical and haematological data are analysed in order to clarify the possible implications of this chromosome anomaly. The following points are considered: 1) In spite of the apparent variability of clinical forms in which monosomy 7 is found, several characteristics are common to all monosomy 7 patients, i.e. the presence of a preleukaemic phase and blood and marrow features suggesting the early involvement in the disease of all marrow cell lines. The different diagnoses associated with monosomy 7 are correlated with different steps of a unique myeloproliferative disease whose typical course can be reconstructed. 2) monosomy 7 has a negative prognostic value. When it is found in a preleukaemic disorder it indicates a high risk of progression to AML, while in AML it implies recurrent infections, poor response to therapy and short survival. 3) The significance of the lack of Colton blood group antigens in monosomy 7 patients is discussed, with particular regard to the fact that the patients in whom this lack was found are the only ones who had not received transfusions in the months before the tests were done. 4) The finding of defective neutrophil chemotaxis in monosomy 7 patients is confirmed and the clinical importance of this fact is emphasized. 5) The data on the 14 patients support the opinion that AML, in general, is heterogeneous in origin. It is postulated that monosomy 7 is a marker of a specific pathogenetic pathway of AML, which implies the beginning of the malignancy in a pluripotent stem cell.- - - - - - - - - - ranking = 0.14285714285714keywords = antigen (Clic here for more details about this article) |