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Presents the use of fractal compression methods for image filtering. Inhomogeneous structure of images and their corruption by additive, multiplicative or pulse interferences; Image filtering and choice of image model; Compression and filtering of images with fractal compression method; Details of the application of the method for image filtering; Improvement in the quality of filtering due to joint use of near and far correlation links manifesting itself as a self-similarity of the image at various scaling.

HpaII/MspI blot-hybridization analysis of the 5'-end region of the calcitonin (CT) gene methylation in cells of bone marrow and peripheral blood of patients with acute lymphoblastic leukemias (ALL) has been carried out. ALLs are accompanied by hypermethylation of the inner cytosine in the CCGG sequences of this region of the CT gene. The level of hypermethylation of the CT gene corresponded to the degree of disease progression and malignancy. At a long-term remission, hypermethylation of the CT gene is not observed. In case of primary resistance or if the complete remission has not been achieved the CT gene remained hypermethylated. It has been shown that in relapse the normal CT gene methylation pattern reversed to hypermethylation. This phenomenon was detected 1-8 months before the obvious clinical and laboratory signs of the disease progression (relapse). The large size of abnormal HpaII-fragments of the 5'-end region of the calcitonin gene had a direct correlation with the malignancy status of ALL.

In 1995-1999, 67 patients with relapsed Hodgkin's disease or refractory to chemotherapy (group A--first relapse, B--primary refractory disease, and C--repeated relapse) received cytoreductive (dexaBEAM, DHAP) therapy followed by high-dose BEAM chemotherapy and autologous bone marrow or blood cell transplantation. Early postoperative transplant-related mortality rate was 4.5%. At day 100, complete remission rates were: group A--95.6%; B--74.1%; and C--76.5%. Survival for all patients was: overall--61.9%; event-free--43.9%; disease-free--46%; and relapse-free survival--49.5%. Such factors as primary refractory disease, age over 30 years and response to cytoreductive therapy had significant influence on overall survival prognosis.

Aim: Investigation of the response to antilymphocytic globulin (ALG) and transplantation of allogenic bone marrow (TABM) in patients with a severe form of aplastic anemia (AA)., Materials and Methods: 15 patients were treated for severe AA in 1995-1997. 8 patients of group 1 were given ALG/cyclophosphamide with subsequent TABM from HLA-identical sib donor. To prevent graft versus host reaction the patients took cyclosporin A (CSA) + prednisolone. Those who had no sib donor (7 patients) were treated with ALG/CSA (group 2)., Results: A complete remission at 7-30-month follow-up was observed in 6 patients of group 1. One patient died of infectious complications in rejection of the transplant and one patient died of acute graft versus host reaction. None of group 2 patients achieved the remission. One patient died of infectious complications. The others need continuous hemotransfusion therapy., Conclusion: In spite of high probability of early complications after TABM, TABM-subjected patients are more likely to achieve a complete remission and recurrence-free survival than those given immunosuppressive therapy alone.

Eighteen patients with relapsed or refractory Hodgkin's disease (HD) have been treated with high-dose chemotherapy (BEAM regimen) followed by autologous peripheral stem cells and/or bone marrow rescue. There were no treatment-related deaths. Overall response rate was 82%. With a median follow-up of 10 months (3-24 months) overall survival and freedom from progression were 100 and 94% (95% confidence interval 58-97%), respectively. The use of peripheral stem cells in addition to bone marrow resulted in a significant shortening of the time to engraftment (p < 0.01). The BEAM regimen is an effective conditioning schedule which is well tolerated.

Twenty patients with resistant and relapsed Hodgkin's disease were included into this investigation. The treatment effectiveness and regimen-related toxicity of BEAM-protocol were evaluated. Stem cell transplantation (SCT) was carried out either as bone marrow transplantation (BMT) in 11 patients or peripheral blood stem cell transplantation (PBSCT) in 9 patients. A comparison of the results pointed to a significant decrease in neutropenia duration, fewer blood transfusions needed and shorter stay in hospital in the PBSCT group. Complete remission was observed in 90% of patients of the SCT group, 91%-in BMT and 89%-PBSCT groups. It was found that high-dose chemotherapy followed by SCT is more effective in the treatment of resistant and relapsed Hodgkin's disease and, in certain situations, it is a treatment of choice. As to the toxicity of BEAM-protocol, it does not exceed those of the other chemotherapy modalities used in SCT.

The Bone Marrow Transplantation Program in Belarus was founded in 1992, and in 1993, a Bone Marrow Transplantation Centre was created in Minsk. From February 1994 to April 1996, 19 allogeneic bone marrow, 16 autologous bone marrow and 10 autologous peripheral blood stem cell transplantations were performed. Reasons for transplantation included chronic myeloid leukemia, multiple myeloma, severe aplastic anemia, acute myeloid leukemia, acute lymphoblastic leukemia, progressive myelofibrosis, Hodgkin's disease, non-Hodgkin's lymphoma, and neuroblastoma. Among the patients were two liquidators involved in the Chernobyl cleanup activity, both of whom underwent allogeneic bone marrow transplantation. A variety of ablative preparative regimens were used, and blood progenitor cells were mobilized by treatment with Cytoxan and granulocyte colony-stimulating factor. Therapy-related deaths resulted from graft-versus-host disease, septic shock, veno-occlusive disease bleeding and intestinal pulmonary fibrosis. Because the transplantation procedures were carried out on people who continued to be exposed to low-level irradiation, the post-transplantation period included a conservative strategy for prevention of graft-versus-host disease. There was nothing unusual about the post-transplantation period, although uncertainty about the continuing radiation dose should be taken into account when interpreting these data.

The authors propose their own system of assessment of high-dose polychemotherapy toxicity. The system was applied to toxic complications of high-dose polychemotherapy in 31 patients with hematological malignancies subjected to allogenic, autologous bone marrow transplantation and transplantation of stem cells from peripheral blood within the scope of different protocols of high-dose polychemotherapy in conditioning regimen. A special scale developed in the Belarus Center for Bone Marrow Transplantation basing on the above system provides prediction of survival in early post-transplantation period.

Investigators from Belarus Center for bone marrow transplantation examined the efficacy of preventing hemorrhagic cystitis induced by high-dose cyclophosphamide in preparation for hemopoiesis precursor transplantation in 22 patients with hematological diseases. The proposed preventive method implied administration of mesna (2-merkaptoetan-sulphonate) and alkaline forced diuresis. Its effectiveness was found high.

The first 10 bone marrow transplantations (BMT), 6 of the allogenic (allo-BMT) and 4 autologous (auto-BMT) were performed from February to June 1994 in Byelarus Center for Bone Marrow Transplantation. Two of the patients were experiencing the first complete remission of acute lymphoblastic leukemia (ALL), one of them - the first ALL recurrence, three patients with acute myeloblastic leukemia had the first complete remission, four patients had a chronic phase of chronic myeloid leukemia. In auto-BMT bone marrow (BM) was stored in liquid hydrogen after programmed freezer. An average yield of nucleated cells (NC) after taking and separation of allo-BM made up 3.0 x 10(8) cell/kg and 2.7 x 10(8) cell/kg in auto-BMT. After thawing of BM NC yield reached 1.5 x 10(8) cell/kg (0.8-2.3) x 10(8) cell/kg. CFU concentrations persisted at 24.7 x 10(4) (5.0-40.4) x 10(4) cell/kg body weight. The mean duration of leukocyte, neutrophil and platelet rise to the levels of over 1.0 x 10(9)/l, 0.5 x 10(9)/l, 20 x 10(9) cell/l, respectively, and the last time red cells were transfused were 23 (19-33), 23 (19-31), 22 (9-51), 4.5 (0-19), respectively. One ALL (first complete remission) patient died on day 52 after allo BMT of severe hepatic venous-occlusive disease. The other ALL patient (the first relapse) developed another relapse on day 112 after BMT. The rest 8 patients are in satisfactory condition.