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Biomedical subjects

J Tamáska

Publications and source records attributed to J Tamáska.

10 recordsLinked to original sources

[Clinical and immunopathological significance of chimerism in bone marrow and organ transplantations]

Chimerism is an exceptional immunogenetic state, characterized by the survival and collaboration of cell populations originated from two different individuals. The prerequisites to induce chimerism are immunosuppression, myeloablation or severe immunodeficiency of the recipients on one side and donor originated immuno-hematopoietic cells in the graft on the other. Special immunogenetic conditions to establish chimerism are combined with bone marrow transplantation, transfusion and various kinds of solid organ grafting. There are various methods to detect the type of chimera state depending on the immunogenetic differences between the donor and recipient. The chimera state seems to be one of the leading factors to influence the course of the post-transplant period, the frequency and severity of graft-versus-host disease (GVHD), and the rate of relapse. However, the most important contribution of the chimeric state is the development of graft versus leukemia (GVL) effect. A new conditioning protocol (DBM/Ara-C/Cy) for allogeneic BMT in CML patients and its consequence on chimera state and GVL effect is demonstrated.

Journal Article↗

Immunological importance of chimerism in transplantation: new conditioning protocol in BMT and the development of chimeric state.

Chimerism is an exceptional immunogenetic state, characterized by the survival and collaboration of cell populations originated from two different individuals. The prerequisits to induce chimerism are immuno-suppression, myeloablation, or severe immunodeficiency of the recipients on the one side and donor originated immuno-hematopoietic cells in the graft on the other. The pathologic or special immunogenetic conditions to establish chimerism are combined with bone marrow transplantation, transfusion, and various kinds of solid organ grafting. Different types of chimerism are known including complete, mixed and mosaic, or split chimerism. There are various methods used to detect the type of chimera state, depending on the immunogenetic differences between the donor and recipient. The induction of complete or mixed chimerism is first determinated by the effect of myeloablative therapy. The chimera state seems to be one of the leading factors to influence the course of the post-transplant period, the frequency and severity of GVHD, and the rate of relapse. However, the most important contribution of the chimeric state is in development of graft versus leukemia effect. A new conditioning protocol (DBM/Ara-C/Cy) for allogeneic BMT in CML patients and its consequence on chimera state and GVL effect is demonstrated.

Antineoplastic Agents, Alkylating↗

[Systemic mastocytosis].

The systemic mastocytosis is a rare disorder, however, the authors recently diagnosed two cases causing diagnostic problems. The diagnosis was proved by bone marrow biopsy in both patients. The authors review the diagnostic pathway considering the pitfalls. According to their conclusion, the most important factor in the diagnosis of systemic mastocytosis is to think of the possibility of systemic mastocytosis.

Aged↗

[Polycytemia vera in an 11-year old girl].

The case of an 11 year old girl with three line type of polycythaemia vera, with 4 cm splenomegaly and a plethoric complexion is presented. Peripheral blood values were as follows: RBC: 7.75 x 10(12)/l, Hb: 18.8 g/l, WBC: 15.2 x 10(9)/l, platelets: 920 x 10(9)/l. Serum erythropoietin level: < 1 mU/ml. In vitro, erythroid colonies developed from the bone marrow in the absence of added erythropoetin. For three years the haematocrit value has been controlled by regular venesections. Since extreme thrombocytosis developed, the treatment was continued with interferon alpha. Different treatment protocols are discussed.

Age Factors↗

[Progression of cutaneous T cell lymphoma in leukemia].

Transition of a (probably primary) cutaneous non-Hodgkin's lymphoma to T-stem cell leukaemia was observed in a case. Unusual clinical features, histological and laboratory data hampered the diagnosis-making of this rare disease. Using the ALL-BFM 90 HRG protocoll complete remission was achieved. Under the treatment varicella-zoster virus encephalitis took place.

Child↗

[Experience with the molecular genetical detection of the chimera gene of the Philadelphia chromosome].

Molecular genetical techniques could be developed for detection of the chimera gene of Philadelphia chromosome or that of its gene product, due to the relatively conserved structure of the chimera gene. The authors successfully analysed 123 blood/bone marrow samples from 106 patients using these molecular techniques adapted from the literature. Patients were classified by the first diagnosis, 65 CML, 7 AML, 13 ALL patients were studied. 12 patients had the diagnosis of myeloproliferative syndrome, and 9 patients were after bone marrow transplantation. 57% of the total, and by diagnosis, 74% of CML, 28% of AML, 54% of ALL, and 33% of post-transplant samples have shown the chimera gene structure characteristic for Philadelphia chromosome. All patients of myeloproliferative syndrome were negative. In some cases the authors had the opportunity to study simultaneously the peripheral blood and the bone marrow sample of the same patient and of the same date. The ratio of the positivity of the two samples varied from one to infinite. The authors could follow the effect of interferon in one case, the change of clonality of the leukemic cell line in an other case. They had the opportunity to detect two different abnormal gene structures in the sample of an AML patient.

Chimera↗

[Importance of the detection of minimal residual disease in the management of acute leukemia].

Between 1984-1988, 57 adult acute leukemic patients were treated with intensive combined chemotherapy in the National Institute of Haematology and Blood Transfusion. For the evaluation of response to therapy, 4 investigations were performed in parallel: bone marrow aspirate, bone marrow biopsy, cytogenetic analysis and bone marrow culture. Nonparametric test for samples taken for the evaluation of remission status showed that bone marrow biopsy was significantly the most sensitive method for the detection of residual disease. The bone marrow culture was also on the borderline of significance, but the low CFU-GM level did not always correlate with the further clinical course. Occasionally, karyotypic abnormality was the only sign of the residual disease. It would be of great importance to quantitate the minimal residual disease in order to evaluate and compare the various intensive postinduction therapeutic strategies.

Adolescent↗