Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Survival of patients with aplastic anemia after immunosuppressive therapy with ATG/ALG ranges from 35% to 60%. However, long-term follow-up on these patients has indicated a high frequency of hematologic complications, including PNH, myelodysplasia, ANL, and recurrent aplasia. In contrast to immunosuppressive therapy, allogeneic marrow transplantation results in cure of aplasia. Problems initially limiting the success of HLA-matched allogeneic marrow transplants included graft rejection and complications associated with acute and chronic GVHD. Infusion of donor buffy coat cells along with marrow or alternatively more intensive immunosuppressive regimens containing irradiation have substantially decreased the risk of rejection. However, buffy coat infusion increases the incidence of chronic GVHD and irradiation treatment adds to toxicity of the conditioning regimen as well as producing long-term complications. The incidence and severity of acute GVHD have been significantly decreased by the use of MTX/CSP as GVHD prophylaxis; however, this regimen has had no impact on the incidence of chronic GVHD. Long-term survival in multiply transfused patients after HLA-identical marrow transplantation is on the order of 60% to 70%; survival in untransfused patients approximates 80%. Patients less than age 18 transplanted on protocols currently active in Seattle have greater than 90% survival. Further increases in survival must come from improvement in preventing and treating chronic GVHD. Patients diagnosed with aplastic anemia should have rapid HLA typing performed to identify possible marrow donors. Transfusions from prospective marrow donors should be avoided and the patient referred to a major treatment center. We continue to recommend allogeneic marrow transplantation for patients with severe aplastic anemia who are less than 40 years old and who have HLA-identical related donors. Immunosuppressive therapy should be tried first in patients without HLA-matched donors and for patients over the age of 40. HLA-mismatched marrow transplantation and use of unrelated marrow donors for severe aplastic anemia remain areas of active research.
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PMID:Treatment of aplastic anemia. 219 14

One hundred forty-seven consecutive patients with leukemia, myelodysplastic syndrome, or aplastic anemia were treated by marrow grafts from genotypically HLA-identical siblings (n = 122) or HLA-haploidentical family members (n = 25). Haploidentical recipients differed from their donors for no more than one HLA locus on the nonshared haplotype. All were given postgrafting immunosuppression with a combination of methotrexate and cyclosporine. In a randomized study we explored whether prednisone administered from day 0 through 35 along with methotrexate/cyclosporine could improve prevention of acute graft-versus-host disease (GVHD). The GVHD incidence in patients not given prednisone was comparable with that previously reported with methotrexate/cyclosporine. Unexpectedly, significant increases in acute and also chronic GVHD were seen in HLA-identical recipients administered prednisone, but not in the small number of patients administered HLA-nonidentical grafts. However, the resultant increase in transplant-related mortality in patients administered prednisone was offset by an increase in leukemic relapse in patients not administered prednisone, presumably related to the absence of a graft-versus-leukemia effect. Therefore, overall disease-free survival of the two groups of patients was comparable, with slightly more than 50% of the patients being alive at more than 2 years after transplantation. We speculated that prednisone adversely affected GVHD prophylaxis, interfering with methotrexate's cell cycle-dependent suppression of donor lymphocyte proliferation in response to host antigens. In a pilot study we explored whether beginning prednisone on day 15, after completion of methotrexate administration, would avoid this adverse effect. The GVHD incidence in patients administered methotrexate/cyclosporine along with "late" prednisone was comparable with that in patients not administered prednisone. We conclude that methotrexate/cyclosporine is effective in decreasing the incidence of grade II through IV GVHD, and that the addition of prednisone to this regimen is not beneficial in recipients of HLA-identical marrow grafts.
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PMID:What role for prednisone in prevention of acute graft-versus-host disease in patients undergoing marrow transplants? 220 81

A survey of the results of marrow transplantation for severe aplastic anemia (SAA) and myelodysplastic syndrome (MDS) in Japan is reported. Of the 152 patients with SAA, 109 were alive between 2 and 132 months following transplantation and the probability of survival at 5 years was 70% (for the patients with grafts from HLA-matched siblings) and 100% (for the patients with grafts from monozygous twins). Survival rate at 3 years for the patients with grafts from family members other than HLA-matched siblings was 46%. The chance of survival was influenced by conditioning regimen and recipient's age. Recipients with sustained engraftment had a significantly higher survival rate than those with graft failure (83% vs 11%, p less than 0.001). Since 1985, the results of transplantation from HLA-matched siblings have improved and the 3-year survival is more than 90% for patients under 20 years old. For MDS, the actuarial survival at 3 years was 42%. The chance of survival was not influenced by the FAB classification, patient's age, patient's sex, interval from diagnosis to transplant, karyotype anomaly or graft versus host disease.
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PMID:Bone marrow transplantation for patients with severe aplastic anemia and myelodysplastic syndrome. 262 63

Evaluation of anti-HLA antibody (HLA-Ab) by lymphocytotoxicity test (LCT) was reviewed in 69 patients with hematopoietic diseases. Twenty-five (36.2%) of these 69 patients developed HLA-Ab at some time during their treatment course. In patient characteristics, eleven of 32 patients with ANLL (34.4%), one of ten patients with ALL (10%), four of nine patients with CML-BC (44.4%), six of seven patients with AA (85.7%), two of four patients with MDS (50%), and one of seven patients with other types (14.3%), who had random-donor transfusion, developed HLA-Ab. Transfused leukocytes count during two months from initial transfusion were compared between LCT positive group and LCT negative group. There were no significant differences between leukocytes count (13.8 x 10(9] of LCT positive group and that (14.2 x 10(9] of LCT negative group. As the result, we can enumerate the following factors, which are important to develop HLA-Ab. The HLA phenotype and immunity of patients may have a more important role than total transfusion volume. The longterm and continuous transfusion may increase the possibility to develop HLA-Ab. The transfusion purging leukocytes may diminish the occasions of alloimmunization. HLA-matched platelet transfusions were best against the patients who developed HLA-Ab and became refractory to platelet transfusion.
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PMID:[Measurement of anti-HLA antibody by lymphocytotoxicity test in patients with hematopoietic diseases]. 279 92

It is important to make the correct diagnosis of MDS and to exclude very carefully all other disorders that may induce dysplastic features in the bone marrow. In patients without excess of bone marrow blasts, cytogenetics and in vitro bone marrow cultures may aid in making the correct diagnosis. MDS patients without excess of bone marrow blasts or symptomatic cytopenia or cytogenetic abnormalities associated with poor prognosis should be followed on a regular basis with sequential examinations of blood counts and bone marrow specimens. In the absence of obvious disease progression, ie, increasing cytopenia or increasing percentage of marrow blasts, patients should only receive supportive care. An increase in RBC requirements alone is insufficient reason to start cytotoxic therapy. Once progression of the disease has been well documented, cytotoxic treatment is indicated. There is no reason to delay treatment until these patients have progressed to overt AML. In patients over the age of 50, the best available therapy is low-dose cytarabine with a 30% probability of a good response; this therapy requires careful supervision and the availability of intensive supportive care. In patients under 50 years with progressive disease, or with clear evidence of a poor prognosis, allogeneic BMT is the therapy of choice if a HLA-identical sibling can be identified. In those patients who lack a HLA-identical sibling, intensive combination therapy is the treatment of choice and should preferably include high-dose cytarabine. Intensive consolidation therapy will be necessary for a durable remission. Trials with inducers of differentiation remain experimental. Results to date have been disappointing.
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PMID:Management of the myelodysplastic syndromes. 282 13

In vitro coculture studies were performed in five patients with severe aplastic anemia (SAA) and their normal HLA-matched donors before and after allogeneic bone marrow transplantation (BMT) to determine whether the erythropoietic function of T cells is abnormal in this disorder. These coculture studies used fresh or cryopreserved marrow T lymphocytes with fresh or cryopreserved marrow T cell-depleted target cells. Four of five aplastic patients had little or no transfusion exposure before studies. The composite results showed that, in comparison to the erythropoietic effects of normal HLA-identical marrow T lymphocytes or engrafted T lymphocytes, T lymphocytes collected from the aplastic patients before BMT consistently suppressed or failed to support CFUE and BFUE growth optimally from autologous marrow, HLA-identical marrow, or engrafted aplastic T cell-depleted marrows. This T cell abnormality was not observed in four multiply transfused leukemics and three patients with myelodysplastic syndrome. Marker analyses of SAA marrow T lymphocytes performed before and after BMT suggested that the erythropoietic functional abnormality was due to abnormal marrow T cell composition reflecting an excess of activated Tac+, T3+, T11+ lymphocytes. Collectively, these in vitro studies provide firmer in vitro evidence implicating T cells in the pathogenesis of SAA. The erythropoietic T cells abnormalities in SAA are fully corrected by allogeneic BMT.
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PMID:In vitro evidence for disappearance of erythroid progenitor T suppressor cells following allogeneic bone marrow transplantation for severe aplastic anemia. 296 76

A treatment with cytosine arabinoside in low doses is administered to 3 children affected by refractory anemia with myeloblast in transformation. The remission is obtained in 3 cases. One child relapsed at 24 months. The other 2 children are in persistent remission at 40 and 48 months. This relatively non-aggressive mode of treatment seems to have a place in children affected by myelodysplasia and for whom allografting from an HLA-identical donor is not available.
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PMID:Efficacy of low-dose Aracytine in 3 cases of refractory anemia in transformation in children. 297 72

Although the majority of bone marrow transplants (BMT) have been performed using HLA-identical sibling donors, BMT may also be successful when the donor is a haploidentical partially matched relation or a well-matched unrelated volunteer. For patients with acute lymphoblastic leukaemia or acute myeloid leukaemia, an alternative to allogeneic BMT using a sibling donor is the use of autologous marrow, although the period of follow-up for such studies is still relatively short and final assessment must await the results of randomized trials. In contrast patients with chronic myeloid leukaemia, severe aplastic leukaemia or myelodysplasia who lack suitable related donors are prime candidates for well-matched unrelated donor transplantation. In this paper we discuss the value of various methods for identifying unrelated donors, the size and costs of maintaining volunteer panels in relation to the probability of finding a matched donor for an individual patient and some of the criteria on which the choice between a mismatched family member donor and a matched unrelated donor can be based.
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PMID:The unrelated bone marrow donor. 314 31

Leukaemic clonogenic cells, capable of forming colonies of blast cells in an in-vitro assay, were examined for surface antigen expression using a panel of monoclonal antibodies (Mabs) to stem cell and myeloid differentiation antigens in nine cases of acute myeloid leukaemia (AML) and four cases of chronic myeloid leukaemia in myeloid blast crisis (CML-MBC). Clonogenic cells were found to be most frequently positive with anti-HLA-DR (positive in 100% cases) and RFB-1 (71%) Mabs, with significant reactivity also being seen with CD-33 (69%) and CD-13 (61%) myeloid specific antibodies. CD-11b and CD-15 antigens, expressed predominantly on mature leucocytes, were not significantly expressed on the clonogenic population. Interestingly, the CD-34 antigen, detected by MY-10 Mab on normal myeloid progenitor cells, was demonstrated on the clonogenic fraction of only one of seven cases tested. A discrepancy between antigen expression of clonogenic cells and immunophenotype of the total leukaemic population was frequently seen, with "early" markers (CD-33, HLA-DR, RFB-1) expressed on a higher proportion of the clonogenic fraction than the overall population, while the converse was the case for the "later" marker, CD-11b. Based on the known normal distribution of differentiation antigens, particularly the CD-13 antigen, cases could be ranked according to clonogenic phenotype into immature (CD-13- HLA-DR+ CD-33+ or CD-33-; five cases), and mature (CD-13+ HLA-DR+ CD-33+; eight cases), levels. However, there was no correlation between these maturation levels and the morphology according to the FAB classification. Of note, the mature group included three CML-MBC, as well as two AML cases with a history of myelodysplasia or myeloproliferative disorder. These immunophenotypic findings indicate a heterogeneity in the level of maturation of the clonogenic population, not only in cases of de-novo AML, but also in AML thought to derive from multipotential stem cells.
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PMID:Immunophenotype of clonogenic cells in myeloid leukaemia. 316 52

Increasing age has been reported to be a poor prognostic factor for survival after bone marrow transplantation. We evaluated causes of death and frequency and type of complications after marrow grafting in 24 syngeneic and 39 allogeneic recipients who were 45 to 68 years old at the time of transplant. Most patients were in an advanced stage of hematologic malignancy. Among patients given syngeneic transplants, actuarial disease-free survival at 7 years is 20%. The major causes of death were relapse of leukemia and idiopathic interstitial pneumonia. Among allogeneic recipients, 9 (23%) are currently alive, and actuarial disease-free survival at 7 years is 11%. Cytomegalovirus pneumonia and septicemia were the most frequent causes of death. Patients over 50 years of age had the poorest survival rate (1/13), but many of these were transplanted in an advanced stage of their disease. However, among 12 patients transplanted while in remission or at an early stage of their disease, 5 are surviving 65 to 1,160 days after transplantation, with an actuarial survival rate of 22% at 3 years. This is in contrast to those who received their transplant in relapse: 2 out of 20 patients (10%) became long-term survivors, with a probability of survival of 15% at 3 years. The actuarial incidence of grade II through IV acute graft-v-host disease (GVHD) was 30% for allogeneic recipients 45 to 50 years of age. This was not significantly different from the incidence in younger patients. In patients 51 to 62 years of age, the actuarial incidence of acute GVHD was 79%; however, this group included three partially HLA-mismatched transplants. Ten of 15 patients surviving at least 3 months developed chronic GVHD. These results suggest that marrow transplantation is feasible and should be considered in patients over 45 years, especially if recipients are in good clinical condition and are at an early stage of their disease, such as the chronic phase of chronic myelogenous leukemia and preleukemia. For patients more than 50 years of age, allogeneic marrow grafting cannot presently be considered first-line therapy.
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PMID:Bone marrow transplantation in patients aged 45 years and older. 351 86


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