Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The soft agar technique was employed to investigate factors involved in the regulation of granulopoiesis in ten children with aplastic anemia. Children with AA had greatly reduced numbers of granulocytic colony-forming cells in their bone marrow and in their peripheral blood when compared to "control" children. Colony-stimulating activity was decreased in five of the ten children tested. Serum from eight children with AA did not inhibit colony formation when added to normal adult bone marrow cells in culture. The defect in AA residues in the stem cell, with involvement of the CSA-producing cells in some cases. The serum of these patients does not contain an inhibitor of granulopoiesis.
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PMID:Granulopoiesis in childhood aplastic anemia. 127 Nov 40

Human serum contains an activity which enhances the release of colony stimulating and burst promoting activity (CSA and BPA). It is low in the majority of normal sera and was found elevated in patients with aplastic anaemia. The patient's 'response' to autologous serum releaser activity was measured by comparing CSA and BPA release by patient cells in percentage of release by normal cells. This 'response' was negatively correlated with serum releaser activity (P = 0.0035 for CSA-release, P less than 0.0001 for BPA-release), i.e. releaser activity was high, when factor release was low. This inverse relationship between releaser activity and the patient's response was also observed in four patients with pancytopenia of causes other than aplastic anaemia. We conclude that elevated serum releaser activity reflects a repair mechanisms which operates when CSA- and BPA-production is inadequate. Thus, releaser activity is likely to be a haemopoietic regulator.
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PMID:Stimulatory serum factors in aplastic anaemia. I. Serum 'releaser' activity for haemopoietic growth factors, a regulator? 241 52

24 patients who were treated with antilymphocyte globulin (ALG) for severe aplastic anaemia (SAA) were tested for endogenous release of granulocyte colony stimulating activity (G-CSA) prior to, and at various intervals after treatment. CSA-production in vitro was induced with autologous serum as a source of 'releaser' activity, avoiding the use of plant mitogens. Before treatment, G-CSA-release was highly variable. Though mean values were higher in the 17 patients who subsequently responded to ALG treatment than in the six non-responders, this difference was not statistically significant. In the 17 responders, G-CSA-release strongly increased prior to improvement of peripheral blood counts. In one responder patient tested-before, and at regular intervals after ALG, CSA-release was high before, abnormally low at 7 d and increased again to high values before the onset of bone marrow reconstitution. In six patients who did not respond to ALG-treatment, G-CSA release decreased after treatment, and a second course of ALG was ineffective when given during this low CSA-phase. Five of the 24 patients developed paroxysmal nocturnal haemoglobinuria (PNH) at 9 months to 3 years after ALG-treatment. In all, the onset of PNH was associated with very low G-CSA-release, whether it had been high or low before treatment. We conclude that low-CSA-release after ALG treatment is a poor prognostic sign. It either indicates progression of marrow failure or heralds PNH. Such patients may be candidates for early bone marrow transplantation or treatment with G-CSF or GM-CSF.
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PMID:Complete recovery of marrow function after treatment with anti-lymphocyte globulin is associated with high, whereas early failure and development of paroxysmal nocturnal haemoglobinuria are associated with low endogenous G-CSA-release. 278 75

Data were obtained from 46 patients with severe aplastic anemia (SAA) who received bone marrow transplants (BMT) from donors other than genotypically HLA-identical siblings. The data were collected in the SAA Registry of the European Bone Marrow Transplant Group. The donors were non-HLA-identical siblings in six cases, parents in 28 cases, a son in one case and unrelated individuals in 11 cases. Fifteen donor-recipient pairs were HLA-A, -B and -DR identical and mutually non-reactive in mixed lymphocyte culture; nine were mismatched at one locus, 17 were mismatched at two or more loci and in five cases data were not available for D/DR determinants. Actuarial survival was predicted by the degree of mismatch. It was 45% for phenotypically HLA-identical grafts, 25% for grafts mismatched at one locus and 11% for graft mismatched at more than one locus. Whether the graft was derived from a family member or an unrelated donor seemed to be less important and results were comparable. Age, patient sex and year of transplant had no significant influence on survival. The use of cyclosporine (CSA) for graft-versus-host disease (GVHD) prophylaxis (n = 21, survival 34%) appeared superior to both methotrexate (n = 9, survival 11%) and to CSA with T cell depletion of donor marrow (n = 13, survival 14%). The causes of death were rejection (n = 15), GVHD (n = 13), pneumonitis (n = 5) and infection (n = 1). Twelve patients are alive at 16-84 months post-BMT.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Bone marrow transplantation for severe aplastic anemia from donors other than HLA identical siblings: a report of the BMT Working Party. 306 21

We have analysed the contribution to megakaryocyte colony formation in methylcellulose made by human plasma, serum, media conditioned by phytohemagglutinin (PHA) stimulated leukocytes (PHA-LCM), erythropoietin (EPO) preparations, and platelets. The culture system was used as a bioassay for megakaryocyte colony stimulating activity (Meg-CSA) in plasma samples of patients with perturbed megakaryocytopoiesis. Preparations of heparinized platelet-poor plasma yielded the most consistent results. Platelet-poor plasma of normal subjects will at best facilitate the occasional growth of small megakaryocyte colonies. Colony frequency and size are reproducibly enhanced in the presence of PHA-LCM as a source of exogenous Meg-CSA. Commercially available EPO preparations may vary in their content of activities that influence megakaryocyte colony formation. Addition of these preparations to cultures that contain plasma and PHA-LCM usually does not enhance colony formation. In contrast to platelet-poor plasma, platelet rich plasma and serum are less supportive of megakaryocyte colony growth. It is suggested that this loss of activity may be related to the release of inhibitors by activated platelets or alternatively caused by absorption of activities by platelets. Plasma samples from patients with megakaryocytopoietic dysfunction may contain components that promote colony formation without addition of PHA-LCM or EPO. This phenomenon is consistently observed for patients with severe aplastic anemia and bone marrow transplant recipients after completion of their ablative preparative regimen.
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PMID:Characterization of human megakaryocytic colony formation in human plasma. 404 52

Sera from patients with aplastic anemia and amegakaryocytic thrombocytopenia contain an activity that stimulates megakaryocyte colony formation in vitro. We have assayed this megakaryocyte colony-stimulating activity (Meg-CSA) in sera of four patients receiving intensive antileukemic chemotherapy to determine whether the appearance of Meg-CSA is a physiologic response to the suppression of megakaryocytopoiesis. Three of the four patients were receiving consolidation or late intensification therapy for acute myoblastic leukemia (AML) in remission. The fourth was receiving induction therapy for de novo AML. During all or part of four chemotherapeutic cycles, serial Meg-CSA levels were assessed and correlated with the corresponding peripheral platelet counts. All courses of cytotoxic chemotherapy resulted in increases in serum Meg-CSA comparable to activity levels present in sera from patients with aplastic anemia. Two of the three patients studied during the early postchemotherapy interval manifested initial serum Meg-CSA elevations seven days before their thrombocytopenic nadirs when platelet counts were still between 100,000/mm3 and 140,000/mm3. Bone marrow recovery from chemotherapy was characterized by a decrease in serum Meg-CSA to pretherapy levels that occurred concurrently with the rise in platelet count to normal. These observations support the hypothesis that Meg-CSA is a physiologic humoral regulator of megakaryocytopoiesis elaborated in response to the depletion of either bone marrow megakaryocytes or megakaryocyte progenitor cells.
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PMID:Human serum megakaryocyte colony-stimulating activity increases in response to intensive cytotoxic chemotherapy. 633 51

Normal serum and serum from four patients with severe aplastic anaemia was fractionated by Sephadex G-150 gel filtration. Fractions were tested for direct haemopoietic activity on colony forming cells in methylcellulose cultures, and for their indirect influence on haemopoiesis via CSA- and BPA-producing cells. All aplastic anaemia sera contained abnormal inhibitors and stimulators. An inhibitor acting on both haemopoietic and factor producing cells, eluting with the IgM fraction was found in all, variable inhibitors of lower molecular weight in single patients. Stimulatory activity of 10 000-50 000 MW acting on factor producing cells, but not on colony forming cells directly, was found in all, a variable stimulator eluting with the very high MW fraction in single patients. In two patients who achieved complete autologous bone marrow remission after treatment with high dose immunosuppression, Sephadex fractions of serum before treatment and remission serum were simultaneously tested on autologous bone marrow in remission. Inhibitors were detected before treatment and disappeared in remission, stimulators were not detectable before treatment but became strong in remission. It is concluded that the effect of aplastic anaemia serum on haemopoiesis in culture is determined by the balance of inhibitors and stimulators on both haemopoietic and CSA/BPA producing cells.
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PMID:Haemopoietic stimulators and inhibitors in aplastic anaemia serum. 634 40

Aplastic anaemia is characterized by multilineage bone marrow failure resulting in pancytopenia. We have successfully treated a young woman with severe aplastic anaemia (SAA) who was resistant to antilymphocyte globulin (ALG) and corticosteroids, with a combination therapy consisting of erythropoietin, cyclosporin A and granulocyte-colony stimulating factor (G-CSF). The patient received erythropoietin and CSA for a period of 10 months without success before G-CSF treatment was started. After 6 weeks of G-CSF therapy she responded with a sustained trilineage recovery. This suggests that immunosuppression together with haemopoietic growth factors may be an effective treatment in patients with SAA who are ALG resistant and cannot be treated by BMT.
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PMID:Sustained trilineage response in a patient with ALG-resistant severe aplastic anaemia after treatment with G-CSF, erythropoietin and cyclosporin A: association of recovery with marked elevation of serum alkaline phosphatase. 751 Sep 93

Scleroderma and aplastic anaemia (AA) occurred simultaneously in a patient. Treatment with antilymphocyte globulin (ALG) resulted in some improvement of the scleroderma and a partial, temporary response of the AA. Both the scleroderma and AA then responded dramatically to cyclosporin (CSA) therapy. Subsequently, a positive Ham's test, together with a reduction in the phosphatidyl-inositolglycan (PIG) anchored membrane proteins decay accelerating factor (DAF, CD55) and membrane inhibitor of reactive lysis (MIRL, CD59), confirmed a diagnosis of paroxysmal nocturnal haemoglobinuria (PNH) affecting erythroid, myeloid and lymphoid cell lineages. We hypothesize that the pathogenesis of the bone marrow failure in this patient was a stem cell defect with a secondary immune response involving T-lymphocytes that may have simultaneously triggered the pancytopenia and scleroderma.
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PMID:Response of aplastic anaemia and scleroderma to cyclosporin. 791 56

Fourteen S/S children with severe SCD were transplanted with marrow from HLA identical siblings. All developed frequent (> 4/y) vasoocclusive crises (VOC) and recurrent acute chest syndrome episodes (n:10), osteitis (n:3), osteonecrosis (n:3), strokes (n:3) or frequent massive deglobulisation (n:2). Two children undergone splenectomy, 2 were chelated and 2 had erythroid allo-immunization. Ethnic origins were from various countries in Africa (n:10), North-Africa (n:3) or West Indies (n:1). At BMT, they were 2y 3m to 14y 9m old (mean:8y 7m). Donors were AS (n:11) or AA (n:3). At first, various conditioning regimens were used consisting of busulfan (BU) plus Cyclophosphamide (CY) at different doses: CY:200 mg/kg (n:12) or 260 mg/kg (n:2); BU:14 mg/kg (n:1), 16 mg/kg (n:9), > 16 mg/kg (n:4); 1 patient received also TLI and one other antithymoglobulin (ATG): 20 mg/kg. GVHD prophylaxis was CSA alone (n:4) or CSA plus short-term MTX (n:10). Median follow-up was 23 months (8 m. to 48 m.). All patients had an engraftment (d13 to d32) with a stable total chimerism in 10/14 patients who are cured. In the 4 others, partial chimerism was observed: one patient had a early and progressive rejection of his graft but is doing very well (28 m. follow-up) without any manifestation of SCD, with a high stable 22% Hb F level. One patient developed an aplastic anaemia 15 m after BMT: a second BMT was achieved 21 m after the first one with engraftment and total chimerism. Two patients have a relatively stable partial chimerism with still undergoing CSA therapy (11 m. and 23 m. follow-up).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Bone marrow transplantation (BMT) in 14 children with severe sickle cell disease (SCD): the French experience. GEGMO. 837 51


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