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171.
Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
172.
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS.  相似文献   
173.
Pretreatment of mice with recombinant murine (rM) colony-stimulating factor-granulocyte-macrophage (CSF-gm) or recombinant human (rH) CSF-g provides partial protection from the lethal effects of ionizing radiation or the alkylating agent cyclophosphamide (CTX). In addition, these agents can significantly prolong survival if administered following lethal doses of irradiation or CTX. To induce protective activity, cytokines were injected 20 hours before lethal irradiation or CTX administration. To accelerate recovery from lethal irradiation, the cytokines must be administered shortly following irradiation, and the induction of maximal levels of activity is dependent on chronic administration. In contrast, because of their longer half-lives, accelerated recovery from alkylating agents requires a delay of at least 24 to 48 hours to allow complete clearance of CTX before administration of a CSF. Studies quantitating peripheral blood leukocytes and bone marrow cellularity as well as colony-forming units per culture (CFU-C) frequency and CFU-C per femur revealed a significant correlation between these parameters and the ability to survive lethal irradiation. This is a US government work. There are no restrictions on its use.  相似文献   
174.
The present study in patients with aplastic anemia was undertaken to determine whether exposure of recipients to donor blood products 24 hr before preparation with cyclophosphamide (1) enhanced the rate of sustained engraftment of marrow from HLA-identical siblings as suggested by animal experiments, (2) increased the rejection rate, in particular in transfused patients who may already have been exposed to donor antigens by blood products, or (3) was of no relevance to the outcome of transplantation of marrow from HLA-identical siblings. One- hundred fifty-five patients were studied, of whom 78 received blood products from the marrow donor 24 hr before cyclophosphamide and 77 did not. A binary logistic regression analysis was applied to the data, simultaneously considering five previously known risk factors for rejection. Results showed that preceding transfusion of donor blood products had neither a significant beneficial nor detrimental effect on the incidence of sustained engraftment.  相似文献   
175.
The effect of hemodialysis and C5a des arg on neutrophil subpopulations   总被引:1,自引:0,他引:1  
Klempner  MS; Gallin  JI; Balow  JE; Van Kammen  DP 《Blood》1980,55(5):777-783
Alterations in neutrophil subpopulations during human hemodialysis or following injection of C5a des arg into rabbits were studied. Whereas baseline peripheral blood neutrophils contained approximately 80% of cells that formed rosettes with IgG-sensitized erythrocytes, neutrophils harvested at the granulocyte nadir (20 min after initiating hemodialysis or the injection of C5a des arg) were markedly depleted of this population. This was seen in a change in ratio of rosette-forming neutrophils (RFN) to non-rosette-forming neutrophils (non-RFN) from 4:1 at 0 time to 1:2 at 20 min. Since non-RFN are less active in assays of adherence and chemotaxis, these alterations in circulating neutrophil populations were reflected in abnormal functional capacity of neutrophils harvested at 20 min. To study the mechanism of RFN depletion, we investigated the ability of C5a des arg to aggregate various human neutrophil suspensions. Unfractionated neutrophils and RFN demonstrated prompt in vitro aggregation in response to C5a des arg, whereas this activated complement fragment induced little aggregation in a population enriched for non-RFN. These results may explain the alterations in neutrophil adherence, chemotaxis, phagocytosis, and bactericidal activity, which have been reported to accompany clinical disorders characterized by in vivo complement activation (i.e., hemodialysis or gram-negative sepsis).  相似文献   
176.
Marrow harvesting from normal donors   总被引:4,自引:2,他引:4  
The experience at a single institution in harvesting marrow for allogeneic transplantation on 1,270 occasions from 1,160 normal donors is presented in detail, together with an analysis of all the donor complications. Four donors were less than 2 years old, and the youngest was 6 1/2 months. No special difficulties were encountered with these young donors. Hospitalization time was three days or less for 99% of the procedures. Six donors had life-threatening complications; three of a cardiopulmonary and two of an infectious nature, and one cerebrovascular embolic episode. Significant operative site morbidity, usually transient neuropathies, occurred in ten procedures. Ten percent of the donations were associated with transient postoperative fever of unknown origin. Increasing donor age was associated with a reduction of the cellularity of the marrow harvest. The use of stored autologous blood permitted the avoidance of blood bank transfusion in 81% of males, 69% of females, and 50% of children. It was concluded that the procedure was associated with a very low risk of complication, but that the involvement of normal donors in such an operation justifies stringent monitoring.  相似文献   
177.
OBJECTIVES: Graves' disease is associated with different human leucocyte antigen (HLA) genes in different populations. This studywasdesigned to examinethe HLA class II associations with Graves' disease in Jamaicans. PATIENTS: One hundred and six Jamaicans with Graves' disease and 104 controls. DESIGN: Oligotyping for HLA-DRB1, DRB3, DQA1 and DQB1 alleles was performed using the polymerase chain reaction sequence specific oligonucleotide probe (PCR-SSOP) technique. RESULTS The frequency of HLA-DRB3 *0101 was increased significantly in the patients compared to controls (38.7% vs. 19.2%; RR = 2.72; Pc < 0.015). The protective alleles for Graves' disease were DRB1 *0901 (0.9% vs. 20.2%; RR = 0.04; Pc < 0.001), DRB1*1001 (0.0% vs. 11%; RR = 0.0%; Pc < 0.01) and DRB4 *0101 (0.0% vs. 12.5%; RR = 0.0; Pc < 0.05). A high female to male ratio of Graves' disease, 25 :1, was observed. Other associated autoimmune diseases were rare and no significant HLA class II associations were found with clinical markers of disease. CONCLUSIONS: Jamaican patients with Graves' disease share the DRB3 *0101 susceptible allele and the DRB4 *01 protective allele but not the susceptible haplotype DRB1 *0301, DRB3*0101, DQA1*0501 with Caucasians.  相似文献   
178.
From 1990 to 1993 we performed a prospective study of busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 30 patients with refractory anemia (RA) undergoing related (n = 17) or unrelated (n = 13) donor marrow transplantation. Nineteen patients survive disease free (63% 3- year actuarial disease-free survival [DFS]) and no patient relapsed. These results were compared to those of 38 historical controls with RA treated with cyclophosphamide and total body irradiation, of whom 22 are disease-free survivors and 1 relapsed. After correcting for significant variables between the two treatment groups, we found no statistically significant difference in outcome based on preparative regimen. Combining data from these 68 patients plus 2 additional patients with RA treated before 1993 with busulfan and cyclophosphamide, we identified four variables independently associated with improved survival: younger age, shorter disease duration, lower neutrophil count pretransplant, and lower hematocrit pretransplant. We also found that 15 patients 40 to 55 years of age had a 46% 3-year actuarial DFS and 26 patients receiving unrelated or mismatched related donor marrow had a 50% 3-year actuarial DFS. We conclude that there does not appear to be any significant difference in outcome based on preparative regimen in this patient population. In addition, allogeneic bone marrow transplantation may be a reasonable approach to therapy of RA early after diagnosis. However, whether early intervention with transplantation prolongs survival over that expected without transplantation cannot be ascertained with certainty from available data.  相似文献   
179.
The hematopoietic stem cells of alpha-thalassemic mice   总被引:1,自引:0,他引:1  
Barker  JE; McFarland  E 《Blood》1985,66(3):595-601
The alpha-thalassemic mouse has a hereditary microcytic anemia, almost certainly has a shortened RBC life span, and is a potential candidate for cell replacement therapy. In a routine study of bone marrow repopulating capacity using hemoglobin as a cell marker, normal donor marrow cells, but not alpha-thalassemic donor marrow cells, completely replaced the host cells. Further analysis showed that at least 30 times more alpha-thalassemic cells were required to outcompete normal donor cells injected simultaneously. The results were more extreme then expected and suggested a defect in a stem cell population as well as in the RBCs. Evidence that the multipotent and erythroid-committed stem cells in alpha-thalassemic mice are not decreased was shown by CFU-S and CFU-E assays. The combined results indicate that the deletion expresses itself most conspicuously in the RBC population. Tests were also performed to analyze repopulation kinetics in the Hbath-J/+ mice. In unirradiated alpha-thalassemic hosts, the hemoglobin from a normal donor persisted but did not replace the host hemoglobin. Sublethally irradiated alpha-thalassemic hosts, on the other hand, were easily repopulated with normal cells. We conclude that the alpha-thalassemic mouse is a good model for cell replacement therapy.  相似文献   
180.
A double-blind, placebo-controlled randomized trial of 13-cis retinoic acid was performed to determine if the drug has a therapeutic effect in patients with myelodysplastic syndromes (MDS). Sixty-eight evaluable patients with MDS were randomized to receive a single, daily oral dose of either 13-cis retinoic acid (13-CRA, 100 mg/m2) or matching placebo. Treatment was continued, when possible, for a period of 6 months. Determination of response to treatment was based on clinical course, repeat bone marrow biopsies, and aspirates and blood counts (CBC) with WBC differential, platelet, and reticulocyte numbers at specified intervals. No significant difference was noted between the two treatment groups in response to test drug (P = .66). One patient (3%) in the 13-CRA group and two patients (6%) in the placebo group had a minor response. Approximately 30% of patients in both groups had progression of their disease, and progression-free survival was nearly identical. Greater than 90% of the patients receiving 13-CRA developed mild or moderate skin toxicity that was reversible with decreasing or discontinuing the drug. Our study did not find that 13-CRA exerts a beneficial therapeutic effect in patients with MDS.  相似文献   
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