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31.
Failure-free survival, defined as the absence of relapse, non-relapse mortality or addition of another systemic therapy, has been proposed as a potential endpoint for clinical trials, but its use has only been reported for single-center studies. We measured failure-free survival in a prospective observational cohort of patients (n=575) with both newly diagnosed and existing chronic graft-versus-host disease from nine centers. Failure was observed in 389 (68%) patients during the observation period. The median follow up of all patients was 30.9 months, and the median failure-free survival was 9.8 months (63% at 6 months, 45% at 1 year, and 29% at 2 years). Of the variables measured at enrollment, ten were associated with shorter failure-free survival: higher National Institutes of Health 0–3 skin score, higher National Institutes of Health 0–3 gastrointestinal score, worse range of motion summary score, lower forced vital capacity (%), bronchiolitis obliterans syndrome, worse quality of life, moderate to severe hepatic dysfunction, absence of treatment for gastric acid, female donor for male recipient, and prior grade II–IV acute graft-versus-host disease. Addition of a new systemic treatment, the major cause of failure, was associated with an increased risk of subsequent non-relapse mortality (hazard ratio=2.06, 95% confidence interval: 1.29–3.32; P<0.003) and decreased survival (hazard ratio=1.51, 95% confidence interval: 1.04–2.18; P<0.03). These results show that fewer than half of patients on systemic treatment will be failure-free survivors at 1 year, and fewer than a third will reach 2 years without experiencing failure. Better treatments are needed for chronic graft-versus-host disease. Clinicaltrials.gov identifier: NCT00637689.  相似文献   
32.
Epstein-Barr virus lymphoproliferation after bone marrow transplantation   总被引:16,自引:7,他引:16  
We review 15 cases of secondary B-cell lymphoproliferative disorders that occurred among 2,475 patients who received allogeneic bone marrow transplants (BMTs) at the Fred Hutchinson Cancer Research Center (Seattle) between 1969 and 1987. The histopathologic findings in 14 of the 15 patients spanned a wide spectrum of lymphoproliferative lesions. One patient had features characteristic of angioimmunoblastic lymphadenopathy. Epstein-Barr virus (EBV) genomic sequences were identified by Southern blot analysis in each of the 13 patients evaluated. Ten of the 12 lesions evaluated originated in donor cells. In two patients, who had mixed chimerism after transplantation, the lesions originated in host cells. The combined evidence from immunoglobulin light chain staining and the analysis of immunoglobulin heavy chain gene rearrangement indicated that the lesions in most patients represented polyclonal proliferations that gave rise to clonal subpopulations. The results indicate an overall actuarial incidence of 0.6% for this complication in BMT recipients. Anti-CD3 monoclonal antibody (MoAb) treatment of acute graft-v-host disease (GVHD) and T cell depletion of the donor marrow were statistically significant risk factors, and GVHD appeared to play a contributing role, particularly in the setting of human leukocyte antigen (HLA) disparity. Two patients had no identifiable risk factors. Prophylaxis or treatment with acyclovir had no detectable effect in the patients; all but two died with uncontrolled lymphoproliferation.  相似文献   
33.
Jansen  J; Ash  RC; Zanjani  ED; LeBien  TW; Kersey  JH 《Blood》1982,59(5):1029-1035
Monoclonal antibody BA-1 binds to B lymphocytes, to cells from most cases of non-T acute lymphoblastic leukemia (ALL), and weakly to neutrophils. To determine whether BA-1 also reacts with hematopoietic progenitor cells (HPC), we studied the effect of removal of BA-1+ cells from human bone marrow on the proliferation in vitro of the trilineage precursor cell CFU-GEMM, and on the committed progenitor cells of granulopoiesis (CFU-C) and erythropoiesis (BFU-E/CFU-E). Complement- mediated cytotoxicity using BA-1 at concentrations far beyond those required to lyse BA-1+ bone marrow cells and ALL cells did not result in inhibition of colony formation in any of the assays. A rosette separation method, using ox red blood cells coated with BA-1, resulted in enrichment of HPC in the BA-1-depleted interface, whereas very few HPC were found in the BA-1-enriched pellet. Both methods indicate that BA-1 does not bind to HPC, although binding of the antibody to the lymphohematopoietic stem cell cannot be excluded yet. The high cytotoxic capacity of the IgM antibody BA-1, and the lack of reactivity with HPC, make the antibody particularly suitable for use in autologous bone marrow transplantation for patients with ALL.  相似文献   
34.
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   
35.
Fifty-two of 175 (30%) survivors of allogeneic marrow transplantation developed chronic graft-versus-hose diseases (GVHD). Five with limited chronic GVHD had an indolent clinical course with involvement of only the skin and liver. Forty-seven with extensive chronic GVHD had an unfavorable multiorgan disorder that resembled several autoimmune diseases. Thirteen patients with extensive disease (group I) were not treated and only 2 survive with Karnofsky scores >- 70%. Mortality resulted from infections and morbidity from sica syndrome, pulmonary and hepatic insufficiency, scleroderma-like skin disease, and contractures. Another 13 (group II) received a median of 8 mo prednisone and/or a brief course of antithymocyte globulin, and 3 survive without disability. The other 21 (group III) were treated with a combination of prednisone (1.0 mg/kg/q.o.d.) and either cyclophosphamide, procarbazine, or azathioprine (all 1.5 mg/kg/day) for a median of 13 mo. Combination therapy was well tolerated with only modest myelotoxicity. Fifteen in group III had a good and 4 a fair response to treatment while 2 with no response died. Azathioprine and prednisone was the most effective regimen. All therapy has been discontinued in 12 group III patients: GVHD returned in 5 (including 2 who died in spite of retreatment) while 7 remain free of GVHD for a median of 11 (range 6-30) mo observation. Only I group III survivor is disabled and 16 of the original 21 are alive 2-4 yr after transplant with Karnofsky scores of 70%-100%. Thus, combination immmunosuppression appears to favorably affect and, in some cases, premanently arrest the adverse natural course of extensive chronic GVHD.  相似文献   
36.
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   
37.
A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen.  相似文献   
38.
Sanders  JE; Thomas  ED; Buckner  CD; Doney  K 《Blood》1987,70(1):324-326
Fifty-seven children between the ages of 3 and 17 years with acute lymphoblastic leukemia (ALL) in chemotherapy-induced second bone marrow remission were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Sixteen died of transplant- related complications. Eighteen relapsed between 56 and 833 days after transplantation, and 16 died of leukemia. Two survive in remission off treatment following chemotherapy. Twenty-three survive in continuous remission from 1.4 to 10.4 years after transplantation and the actuarial analysis shows disease-free survival of 40% with a plateau extending from 2.5 to 10.4 years.  相似文献   
39.
Loss of a whole chromosome 7 or a deletion of the long arm, del(7q), are recurring abnormalities in malignant myeloid diseases. To determine the location of genes on 7q that are likely to play a role in leukemogenesis, we examined the deleted chromosome 7 homologs in a series of 81 patients with therapy-related or de novo myelodysplastic syndrome or acute myeloid leukemia. Our analysis showed that the deletions were interstitial and that there were two distinct deleted segments of 7q. The majority of patients (65 of 81 [80%]) had proximal breakpoints in bands q11-22 and distal breakpoints in q31-36; the smallest overlapping deleted segment was within q22. The remaining 16 patients had deletions involving the distal q arm with a commonly deleted segment of q32-33. To define the proximal deleted segment at 7q22 at a molecular level, we used fluorescence in situ hybridization with a panel of mapped yeast artificial chromosome (YAC) clones from 7q to examine 15 patients with deletion breakpoints in 7q22. We determined that the smallest overlapping deleted segment is contained in a well- defined YAC contig that spans 2 to 3 Mb. These studies delineate the region of 7q that must be searched to isolate a putative myeloid leukemia suppressor gene, and provide the necessary cloned DNA for more detailed physical mapping and gene isolation.  相似文献   
40.
In normal vision, the inputs from the two eyes are integrated into a single percept. When dissimilar images are presented to the two eyes, however, they compete for perceptual dominance, so that one eye's view suppresses that of the other. Recent evidence suggests that this phenomenon, known as binocular rivalry, arises through competition between alternative stimulus interpretations in extrastriate cortex. Because eye-specific information appears to be lost at this stage, it remains unclear how the stimulus conditions that yield binocular rivalry are distinguished from those that produce stable single vision. Using a neural network that models the mammalian early visual system, I investigate here the hypothesis that congruent and conflicting stimuli are distinguished by their different effects on the relative timing of action potentials in primary visual cortex (V1), where monocular inputs are first combined. In the model, congruent stimulation of both eyes results in synchronization of discharges among binocular neurons in V1. By contrast, conflicting stimulation of the two eyes results in neuronal asynchrony in this area. This asynchrony then produces rivalrous response suppression at later stages in the visual pathway. Synchronization of firing in V1, however, prevents such competition, thereby ensuring non-rivalrous responses. These novel effects of spike timing on competition emerge naturally from the network dynamics. The results suggest that input-related differences in relative spike timing at an early stage of visual processing may play an important part in the phenomena both of binocular integration and rivalry; furthermore, they indicate that the temporal patterning of cortical activity may be a fundamental mechanism of selection among competing stimulus representations.   相似文献   
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