Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study shows a marked and protracted activation of HbF synthesis in homozygous beta.-thalassaemia patients transplanted from HLA identical siblings heterozygous for beta-thalassaemia, as compared to patients transplanted from normal donors. HbF synthesis in recipients was much higher in relation to the corresponding bone marrow donor values either normal or heterozygous for beta thalassaemia. gamma-chain synthesis and G gamma/A gamma ratio were also studied in peripheral blood BFU-E from recipients and their donors. BFU-E from donors heterozygous for beta-thalassaemia showed higher gamma chain synthesis as compared to normal donors. Peripheral blood BFU-E gamma/beta + gamma ratios and G gamma percentage were higher in recipients than in their corresponding donors both normal or heterozygotes. The marked and protracted reactivation of HbF synthesis in recipients of heterozygous beta-thalassaemia bone marrow most likely results from an increased erythropoietic stress on erythroid progenitors. In order to obtain adequate Hb levels heterozygous beta-thalassaemia bone marrow should produce more red blood cells to compensate for the low MCH. The magnitude of activation of HbF synthesis was very variable. This variability may result from inherited differences in the capacity of reactivation of HbF synthesis of red cell progenitors from heterozygous beta-thalassaemia under stressed erythropoiesis.
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PMID:Erythropoiesis following bone marrow transplantation from donors heterozygous for beta-thalassaemia. 247 70

An increasing number of diseases may be treated successfully by allogeneic bone marrow transplantation (BMT). Initially used for the treatment of immunodeficiency where a cell series or product is replaced, it has now become routine treatment for many forms of leukemia where the transplant provides the rescue after lethal marrow ablation. Recently, diseases such as thalassemia and other inherited metabolic diseases have also been treated by BMT. Formerly the problems of BMT were mainly concerned with graft versus host disease (GVHD) in HLA-matched transplants with HLA-mismatched ones not being possible as GVHD was usually fatal. Since the development of techniques for T cell removal the incidence of GVHD has greatly diminished. T cell removal has also allowed HLA haploidentical mismatched grafts to be performed successfully for immunodeficiency, but there is still a high graft rejection rate in leukemia. This also occurs to a lesser extent with HLA-matched grafts in leukemia. Furthermore, in certain forms of leukemia, particularly chronic granulocytic leukemia, the relapse rate after T cell-depleted BMT is much higher. Trials of better forms of bone marrow conditioning of the recipient are being attempted in order to prevent graft rejection and leukemia relapse. These include total lymphoid irradiation, heavier irradiation and chemotherapeutic regimens, or the use of in vivo monoclonal antibodies such as CAMPATH 1G or anti-LFA-1 (CD11a). In the future, positive selection of stem cells combined with hemopoietic growth factors may allow engraftment without graft versus host disease. This should become the method of choice for autologous transplantation for malignancy. Two monoclonal antibodies directed against the human progenitor cell antigen 1 (HPCA-1) (CD34) have been used for autologous positive stem cell selection in primates and these cells gave full hemopoietic reconstitution in the animals following lethal total body irradiation.
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PMID:Recent advances in bone marrow transplantation. 256 39

Malignant hemopathies and immune deficiencies are the main indications for allogeneic bone marrow transplantation in children. Among the former, the most common condition is acute lymphoblastic leukemia, in which a bone marrow transplant can be performed during the second or first complete remission (CR). Thirty to 50% and 60 to 75% of these grafts, respectively, are successful. The success rate is 50 to 70% among patients with acute myeloblastic leukemia grafted during the first complete remission, and among patients with chronic myeloid leukemia grafted during the chronic phase. Severe medullary aplasia and Fanconi disease are undoubtedly good indications for bone marrow transplantation, which has a 60 to 70% success rate. Severe combined immune deficiencies (SCID) and Wiskott-Aldrich disease are also good indications for HLA-identical bone marrow transplantation, which is successful in 60% of cases. Among the metabolic diseases, good results have been obtained only in Hurler disease and Gaucher disease. Questionable indications include thalassemia, Blackfan-Diamond disease, and chronic granulomatous disease. Results are disappointing in most metabolic diseases, as well as in non-HLA-identical transplantations in diseases other than SCID.
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PMID:[Allogeneic bone marrow grafts in children. Indications and results]. 268 52

In the course of a prenatal diagnosis for beta thalassaemia by linkage analysis of restriction fragment length polymorphisms, a homozygous beta thalassaemia fetus was misdiagnosed as beta thalassaemia trait. Extensive studies of the polymorphic sites within the beta globin gene cluster in all the members of the family resulted in the conclusion that the paternal chromosome 11 of the newborn was different from that expected. Paternity was confirmed by HLA typing and blood group studies. The analysis of another polymorphic locus on chromosome 11 within the family was in agreement with the possibility of a crossing over between the two paternal chromosomes in a region 5' to the beta gene, previously indicated to contain a 'hot spot' area for recombination. This report underlines the risk of performing prenatal diagnosis using restriction polymorphisms 5' to the beta gene.
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PMID:Meiotic recombination in the beta globin gene cluster causing an error in prenatal diagnosis of beta thalassaemia. 289 35

The use of busulphan and cyclophosphamide permitted engraftment in 44 of 49 children receiving 'displacement' bone marrow transplants. Three patients who received T-cell-depleted marrow cells from HLA-haploidentical donors failed to engraft and other graft failures were due to inadequate induction dosage. Our standard schedule comprises busulphan 80 mg/m2/day x 4 days (adjusted if necessary to a minimum of 4 mg/kg/day or a maximum of 5 mg/kg/day) followed by cyclophosphamide 2 g/m2/day x 4 days but reduced so as not to exceed 75 mg/kg/day, a maximum dose preferred for patients with full marrows (e.g. those with thalassaemia major). Of 21 recipients of mixed lymphocyte culture (MLC)-negative donor marrow cells with full engraftment at 100 days, there were three late rejections. Of patients transplanted with marrow from MLC-positive donors, one had late rejection after cyclosporin A toxicity had necessitated withdrawal of the drug at day + 146 but six other patients, whose cyclosporin A was stopped routinely 1 year, remain well with full grafts. Ten patients died as a result of graft-versus-host disease. We are therefore exploring new approaches to T-cell depletion and storing autologous marrow for use in the event of graft failure. If necessary, a second transplant with busulphan and cyclophosphamide is best performed at 3 months after full recovery of the host. We conclude that elective transplants can be performed successfully in children with normal immune function without the need for irradiation.
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PMID:Engraftment rates related to busulphan and cyclophosphamide dosages for displacement bone marrow transplants in fifty children. 297 9

We have studied a nuclear family containing a single child with severe beta-thalassemia intermedia, a Greek-Cypriot mother with hematological findings of beta-thalassemia trait, and a Polish father who is hematologically normal. Since both the child and her father were heterozygous for a DNA polymorphism within the beta-globin gene, it was possible to clone and sequence the beta-globin gene identical by descent from both the child and her father. A nonsense mutation in codon 121 (GAA----TAA) was found in the beta-globin gene of the child, while the same gene from her father lacked this mutation and was normal. This mutation has not been previously observed among over 200 beta-thalassemia genes characterized in Caucasians. Since the mutation eliminates an EcoRI site in the beta-globin gene, we could show that the mutation is not present in genomic DNA of the father. To rule out germinal mosaicism, sperm DNA of the father was also digested with EcoRI, and the mutant EcoRI fragment was not observed under conditions that would detect the mutation if it were present in at least 2% of sperm cells. Routine HLA and blood group testing supported stated paternity. In addition, studies with 17 DNA probes that detect multiple allele polymorphisms increased the probability of stated paternity to at least 10(8):1. These data provide evidence that the G----T change in codon 121 of the beta-globin gene in the child is the result of a spontaneous mutation that occurred during spermatogenesis in a paternal germ cell.
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PMID:Characterization of a spontaneous mutation to a beta-thalassemia allele. 301 70

The present report summarizes our experience in applying a new approach in bone marrow transplantation for the treatment of beta-thalassemia major. Ex-vivo pretransplant T-lymphocyte depletion with CAMPATH-1 was used for prevention of acute and chronic graft versus host disease and total lymphoid irradiation was added for the conditioning regimen for abrogation of potential rejection of T-cell depleted marrow allografts. Ten patients with homozygous beta-thalassemia major were 9-48 months of age (median 18.5 months) and received HLA-identical allogeneic T-cell depleted marrow after treatment with total lymphoid irradiation, busulfan and cyclophosphamide. Seven patients are alive and free of disease, 3-46 months post-transplantation. The actuarial probability of survival and of disease-free survival at two years was 70%. Three patients died: one of intracranial hemorrhage post-transplantation, one from busulfan interstitial pneumonitis, and one who rejected the first graft and developed fatal chronic graft versus host disease after a second transplant. Seven patients are alive and well with follow-up of 3-45 months, with no signs of acute or chronic GVHD. We conclude that T-cell depleted bone marrow transplantation is indicated for homozygous transfusion dependent young patients with beta-thalassemia who are minimally transfused, particularly in areas where optimal conventional therapy is not feasible.
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PMID:Bone marrow transplantation in beta-thalassemia major. The Israeli experience. 306 78

This study compares the efficacy of 2 posttransplant immunosuppressive regimens for prevention of graft-versus-host disease (GVHD). Forty-four patients, ages 8-15 years, with homozygous beta thalassemia received marrow allografts from HLA-identical siblings following an ablative regimen of busulfan and cyclophosphamide. Twenty-two patients received cyclosporine (CsA) alone and 22 received cyclosporine, cyclophosphamide, and methotrexate for prophylaxis against GVHD. Two who received CsA alone have died (1 of graft rejection and 1 of acute GVHD) as did 4 patients who received 3 drugs (1 of rejection, 1 of acute GVHD, 1 of infection and cardiac failure before engraftment, and 1 of acute respiratory failure before engraftment). One patient in each group rejected the transplant and survives with thalassemia. The probability of developing acute GVHD was 41% for the CsA group and 15% for the 3-drug group (P = less than 0.05). Patients receiving CsA alone had a probability of event-free survival of 86% compared to 77% in the group receiving 3 drugs (P = 0.40) with a followup of 209-706 days. Although the study showed a decrease in the incidence of GVHD in recipients of the more intensive prophylactic regimen, this study was terminated since it was apparent that even if larger numbers of patients were studied it would be difficult to demonstrate a significant survival advantage with the use of this drug regimen.
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PMID:A comparative trial of posttransplant immunosuppression in patients transplanted for thalassemia. Cyclosporine alone versus cyclosporine, cyclophosphamide, and methotrexate. 327 81

This study reviews results of fetal liver transplantation in hematologic disorders including aplastic anemia, leukemia and thalassemia. One hundred and twenty two patients received transplants for aplastic anemia; engraftment was reported in 4 patients; graft-versus-host disease (GvHD) did not occur. Complete and partial responses were reported in one-half of patients, the majority of whom had no evidence of engraftment. Thirty-nine patients received transplants for leukemia. Transient engraftment was reported in 40% and two developed GvHD; survival extended to more than 2 years. The higher rate of engraftment in patients with leukemia suggests a role of pretransplant immune suppression. The risk of GvHD appears to be low despite complete HLA-mismatching. These data suggest a possible role for fetal liver transplantation in man. Future studies should probably be based on preclinical data obtained in large animal models.
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PMID:Fetal liver transplantation in aplastic anemia and leukemia. 332 6

Ten patients with homozygous beta thalassemia, aged from 1 year 7 months to 13 years, underwent bone marrow transplantation from siblings or parents. The first case received 12 mg/kg busulfan, 120 mg/kg cyclophosphamide, and 300 cGy total body irradiation before transplantation; he survives, with a graft, more than 680 days after transplantation. The other nine patients received 16 mg/kg busulfan and 200 mg/kg cyclophosphamide. Two died of transplantation-related complications on days 30 and 55. Seven survive 170 to 580 days after transplantation. Three of the seven surviving patients have durable engraftment (greater than 230 to greater than 550 days) while four patients have autologous hematopoietic recovery. Four of five patients who had less than 50 prior transfusions achieved engraftment. Only one of five patients who had more than 50 prior transfusions achieved engraftment (P less than 0.05). The six-month actuarial survival was 80%; six-month actuarial disease-free survival was 40%. These data demonstrate that bone marrow transplantation may cure thalassemia, but engraftment may be jeopardized among patients who have been heavily transfused or have received marrow from a donor who is not HLA-identical.
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PMID:Marrow transplantation for thalassemia. 333 27


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