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111.
Nonmyeloablative transplantation with or without alemtuzumab: comparison between 2 prospective studies in patients with lymphoproliferative disorders 下载免费PDF全文
Pérez-Simón JA Kottaridis PD Martino R Craddock C Caballero D Chopra R García-Conde J Milligan DW Schey S Urbano-Ispizua A Parker A Leon A Yong K Sureda A Hunter A Sierra J Goldstone AH Linch DC San Miguel JF Mackinnon S;Spanish United Kingdom Collaborative Groups for Nonmyeloablative Transplantation 《Blood》2002,100(9):3121-3127
Although nonmyeloablative conditioning regimen transplantations (NMTs) induce engraftment of allogeneic stem cells with a low spectrum of toxicity, graft-versus-host disease (GVHD) remains a significant cause of morbidity and mortality. In vivo T-cell depletion, using alemtuzumab, has been shown to reduce the incidence of GVHD. However, this type of maneuver, although reducing GVHD, may have an adverse impact on disease response, because NMTs exhibit their antitumor activity by relying on a graft-versus-malignancy effect. To explore the efficacy of alemtuzumab compared with methotrexate (MTX) for GVHD prophylaxis, we have compared the results in 129 recipients of a sibling NMT enrolled in 2 prospective studies for chronic lymphoproliferative disorders. Both NMTs were based on the same combination of fludarabine and melphalan, but the United Kingdom regimen (group A) used cyclosporin A plus alemtuzumab, whereas the Spanish regimen (group B) used cyclosporin A plus MTX for GVHD prophylaxis. Patients receiving alemtuzumab had a higher incidence of cytomegalovirus (CMV) reactivation (85% versus 24%, P <.001) and a significantly lower incidence of acute GVHD (21.7% versus 45.1%, P =.006) and chronic GVHD (5% versus 66.7%, P <.001). Twenty-one percent of patients in group A and 67.5% in group B had complete or partial responses 3 months after transplantation (P <.001). Eighteen patients in group A received donor lymphocyte infusions (DLIs) to achieve disease control. At last follow-up there was no difference in disease status between the groups with 71% versus 67.5% (P =.43) of patients showing complete or partial responses in groups A and B, respectively. No significant differences were observed in event-free or overall survival between the 2 groups. In conclusion, alemtuzumab significantly reduced GVHD but its use was associated with a higher incidence of CMV reactivation. Patients receiving alemtuzumab often required DLIs to achieve similar tumor control but the incidence of GVHD was not significantly increased after DLI. 相似文献
112.
Primary and serially passaged human fetal normal colon epithelial cells have been propagated and characterized with regard to their nature and origin. The cells exhibited many characteristics of colonic epithelial cells including the presence of mucopolysaccharides and carcinoembryonic antigen. Serial passaging of the cultures required supplementing the medium with insulin, transferrin, epidermal growth factor, and cholera toxin. This study also shows that these factors have specific roles in the regulation of growth and morphologic differentiation of the cell cultures. Insulin apparently is mainly associated with cell multiplication, whereas transferrin, epidermal growth factor, and cholera toxin are associated with the maintenance of morphologic differentiation status of the cell cultures. 相似文献
113.
Robertson JD Gale RE Wynn RF Dougal M Linch DC Testa NG Chopra R 《British journal of haematology》2000,109(2):272-279
Human haemopoiesis undergoes profound changes throughout life, resulting in compromised regenerative capacity of haemopoietic stem cells. It has been suggested that telomere shortening results in senescence of haemopoietic stem cell subsets and may influence the balance between stem cell renewal and proliferation. Telomere length and telomerase activity was measured in whole blood leucocytes, neutrophils and T cells from cord blood and individuals aged from 1 year to 96 years. Rapid telomere shortening [700 base pairs (bp)] was demonstrated in the first year of life, followed by a gradual decline of 31 bp/year. T cells were shown to have longer telomeres than neutrophils (mean difference 372 bp, P = < 0.001) but demonstrated similar rates of shortening (20 +/- 0.3 bp/year vs. 22 +/- 0.3 bp/year). Telomerase was detectable in T cells but not in neutrophils, suggesting that telomerase is not the rate-limiting step for regulation of telomere length in haemopoietic cells. Stem cell utilization as measured by X chromosome inactivation patterns was found to be independent of telomere length. This supports the concept that age-dependent skewed haemopoiesis is the result of random stem cell loss or X-allelic exclusion rather than telomeric senescence. These studies provide insight into the ageing process and a reference point for evaluating replicative stress in individuals of different age groups. 相似文献
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116.
Defibrotide for the treatment of hepatic veno-occlusive disease: results of the European compassionate-use study 总被引:8,自引:0,他引:8
Chopra R Eaton JD Grassi A Potter M Shaw B Salat C Neumeister P Finazzi G Iacobelli M Bowyer K Prentice HG Barbui T 《British journal of haematology》2000,111(4):1122-1129
Severe hepatic veno-occlusive disease (VOD) is a recognized complication of autologous and allogeneic stem cell transplantation (SCT) that is often fatal. Defibrotide (DF) is a polydeoxyribonucleotide that has been found to have anti-thrombotic, anti-ischaemic and thrombolytic properties without causing significant anticoagulation. Preliminary studies have demonstrated activity for DF in the treatment of VOD, with minimal associated toxicity. In the present study, 40 patients who fulfilled established criteria for VOD were treated with DF on compassionate grounds in 19 European centres; 28 patients met risk criteria predicting progression of VOD and fatality or had evidence of multiorgan failure (MOF), and were defined as 'poor-risk'. DF was commenced intravenously at a median of 14 d (range, -2 d to 53 d) post SCT at doses ranging from 10 to 40 mg/kg. The median duration of therapy was 18 d (range, 2--71 d). Twenty-two patients showed a complete response (CR) (bilirubin < 34.2 micromol/l and resolution of signs/symptoms of VOD and end-organ dysfunction) [CR = 55%, confidence interval (CI) 40--70%] and 17 patients (43%) are alive beyond d +100. Ten poor-risk patients showed a complete response (CR = 36%, CI 21--51%). These results demonstrate that DF is an active treatment for VOD following SCT and a randomized trial is now underway in order to further evaluate its role. 相似文献
117.
In vivo CAMPATH-1H prevents graft-versus-host disease following nonmyeloablative stem cell transplantation 总被引:9,自引:22,他引:9
Kottaridis PD Milligan DW Chopra R Chakraverty RK Chakrabarti S Robinson S Peggs K Verfuerth S Pettengell R Marsh JC Schey S Mahendra P Morgan GJ Hale G Waldmann H de Elvira MC Williams CD Devereux S Linch DC Goldstone AH Mackinnon S 《Blood》2000,96(7):2419-2425
A novel nonmyeloablative conditioning regimen was investigated in 44 patients with hematologic malignancies. The median patient age was 41 years. Many of the patients had high-risk features, including 19 patients with a previous failed transplant. Recipient conditioning consisted of CAMPATH-1H, 20 mg/day on days -8 to -4; fludarabine, 30 mg/m(2) on days -7 to -3; and melphalan, 140 mg/m(2) on day -2. Thirty-six recipients received unmanipulated granculocyte colony-stimulating factor-mobilized peripheral blood stem cells from HLA-identical siblings, and 8 received unmanipulated marrow from matched unrelated donors. GVHD prophylaxis was with cyclosporine A alone for 38 patients and cyclosporine A plus methotrexate for 6 sibling recipients. Forty-two of the 43 evaluable patients had sustained engraftment. Results of chimerism analysis using microsatellite polymerase chain reaction indicate that 18 of 31 patients studied were full-donor chimeras while the other patients were mixed chimeras in one or more lineages. At a median follow-up of 9 months (range 3 to 29 months), 33 patients remain alive in complete remission or with no evidence of disease progression. Seven patients relapsed or progressed post-transplantation, and 4 of them subsequently died. Four patients died of regimen-related complications. There were no cases of grades III-IV acute GVHD. Only 2 patients developed grade II acute GVHD, and only 1 had chronic GVHD. The estimated probability of nonrelapse mortality was 11%. Although longer follow-up is needed to establish the long-term remission rates, this study demonstrates that this nonmyeloablative preparative regimen is associated with durable engraftment, minimal toxicity, and low incidence of GVHD. 相似文献
118.
The left internal mammary artery is frequently employed as a conduit in coronary bypass surgery. We report a 42-year-old male post-coronary artery bypass grafting patient with, angina on exertion who was found to have multiple atrioventricular fistulae arising from left internal mammary artery to pulmonary vasculature leading to coronary steal and positive stress thallium in left anterior descending territory. These fistulae were selectively embolized with polymer particles leading to improved flow in distal left anterior descending artery. Postintervention, the patient has been asymptomatic for more than 8 months. 相似文献
119.
South Africa Every Death Counts Writing Group Bradshaw D Chopra M Kerber K Lawn JE Bamford L Moodley J Pattinson R Patrick M Stephen C Velaphi S 《Lancet》2008,371(9620):1294-1304
South Africa is one of the few developing countries with a national confidential inquiry into maternal deaths. 164 health facilities obtain audit data for stillbirths and neonatal deaths, and a new audit network does so for child deaths. Three separate reports have been published, providing valuable information about avoidable causes of death for mothers, babies, and children. These reports make health-system recommendations, many of which overlap and are intertwined with the scarcity of progress in addressing HIV/AIDS. The leaders of these three reports have united to prioritise actions to save the lives of South Africa's mothers, babies, and children. The country is off-track for the health-related Millennium Development Goals. Mortality in children younger than 5 years has increased, whereas maternal and neonatal mortality remain constant. This situation indicates the challenge of strengthening the health system because of high inequity and HIV/AIDS. Coverage of services is fairly high, but addressing the gaps in quality and equity is essential to increasing the number of lives saved. Consistent leadership and accountability to address crosscutting health system and equity issues, and to prevent mother-to-child transmission of HIV, would save tens of thousands of lives every year. Audit is powerful, but only if the data lead to action. 相似文献
120.