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991.
Limited studies have reported on outcomes for lymphoid malignancy patients receiving alternative donor allogeneic stem cell transplants. We have previously described combining CD34-selected haploidentical grafts with umbilical cord blood (haplo-cord) to accelerate neutrophil and platelet engraftment. Here, we examine the outcome of patients with lymphoid malignancies undergoing haplo-cord transplantation at the University of Chicago and Weill Cornell Medical College. We analyzed 42 lymphoma and chronic lymphoblastic leukemia (CLL) patients who underwent haplo-cord allogeneic stem cell transplantation. Patients underwent transplant for Hodgkin lymphoma (n?=?9, 21%), CLL (n?=?5, 12%) and non-Hodgkin lymphomas (n?=?28, 67%), including 13 T cell lymphomas. Twenty-four patients (52%) had 3 or more lines of therapies. Six (14%) and 1 (2%) patients had prior autologous and allogeneic stem cell transplant, respectively. At the time of transplant 12 patients (29%) were in complete remission, 18 had chemotherapy-sensitive disease, and 12 patients had chemotherapy-resistant disease. Seven (17%), 11 (26%), and 24 (57%) patients had low, intermediate, and high disease risk index before transplant. Comorbidity index was evenly distributed among 3 groups, with 13 (31%), 14 (33%), and 15 (36%) patients scoring 0, 1 to 2, and ≥3. Median age for the cohort was 49 years (range, 23 to 71). All patients received fludarabine/melphalan/antithymocyte globulin conditioning regimen and post-transplant graft-versus-host disease (GVHD) prophylaxis with tacrolimus and mycophenolate mofetil. The median time to neutrophil engraftment was 11 days (range, 9 to 60) and to platelet engraftment 19.5 days (range, 11 to 88). Cumulative incidence of nonrelapse mortality was 11.6% at 100 days and 19 % at one year. Cumulative incidence of relapse was 9.3% at 100 days and 19% at one year. With a median follow-up of survivors of 42 months, the 3-year rates of GVHD relapse free survival, progression-free survival, and overall survival were 53%, 62%, and 65%, respectively, for these patients. Only 8% of the survivors had chronic GVHD. In conclusion, haplo-cord transplantation offers a transplant alternative for patients with recurrent or refractory lymphoid malignancies who lack matching donors. Both neutrophil and platelet count recovery is rapid, nonrelapse mortality is limited, excellent disease control can be achieved, and the incidence of chronic GVHD is limited. Thus, haplo-cord achieves high rates of engraftment and encouraging results.  相似文献   
992.
993.
Haematopoietic stem cell transplantation (HSCT) remains the only cure for most haematological malignancies, however, the mortality rate remains high. Complications after HSCT include relapse, graft versus host disease (GvHD), graft rejection and infection. Over the last few years several groups, have demonstrated that non‐HLA gene polymorphisms can be predictive of outcome after HSCT. Since the glucocorticoid cortisol is pivotal in the regulation of the immune system, we decided to examine single nucleotide polymorphisms (SNPs; rs6198, rs33388 and rs33389) within the glucocorticoid receptor (GR) and correlate with HSCT outcome. The training set consisted of patients (n = 458) who underwent HSCT for acute leukaemia between 1983 and 2005. In the recipients, the absence of the ACT haplotype and absence of the T allele of rs33388 were associated with decreased OS and the absence of the ACT haplotype, the absence of the T allele of rs33388 and the presence of the ATA haplotype were associated with increased risk of relapse. In addition, the presence of the ACT haplotype in the recipient showed a trend to be associated with increased risk of chronic graft versus host disease (cGvHD). The patients in this cohort received mainly myeloablative conditioning (n = 327). The SNPs in the glucocorticoid receptor were then investigated in a validation set (n = 251) of HSCT patients transplanted for acute leukaemia from 2006. This cohort contained significantly more patients that had received reduced intensity conditioning (RIC). Some of the results could be validated in these patients. However, contrary to the training set, the absence of the haplotype ACT in the donor in this cohort was associated with increased risk of cGvHD. Differences in the conditioning were shown to influence the results. These results are the first to associate GR SNPs with HSCT outcome and demonstrate the inherent problems of replicating SNP association studies in HSCT, due to different pre‐transplant regimens.  相似文献   
994.
《Diagnostic Histopathology》2018,24(12):508-513
Liver transplantation is becoming more widely used for the treatment of numerous diseases. Liver pathology has an important role in both donor selection and guidance for treatment decisions to preserve allografts. Pathologists are increasingly requested to perform frozen section analysis of donor liver because suboptimal allografts need to be utilized because of the shortage of available donor livers. Post-transplant liver biopsies can seem overwhelming due to the wide differential diagnosis compared to that for non-allograft liver biopsies. When evaluating allograft liver biopsies, attention to the morphologic pattern and correlation with clinical findings is essential. This review provides a brief overview of the differential diagnoses encountered in allograft biopsies and a guide to diagnosis using histologic findings and the timeline after transplantation.  相似文献   
995.
Effusion‐based lymphoma (EBL) is a rare but distinct entity of large B‐cell lymphoma in effusion without association with human herpes virus‐8 (HHV‐8). Spontaneous regression after pleurocentesis has been observed; but to our knowledge, there are no reports on the morphological and molecular features of subsequent aspirations in regressing cases. Here, we report the case of a 92‐year‐old male with chronic obstructive pulmonary disease, who presented with right pleural effusion. He had no human immunodeficiency virus, hepatitis B virus, or hepatitis C virus infection, and CT scans revealed no mass lesion. The first pleural effusion aspiration cytology revealed large lymphoma cells with vesicular nuclei, irregular nuclear contours, and prominent nucleoli, consistent with EBL. The second aspiration cytology showed a few slightly enlarged lymphocytes in a background of small lymphocytes. Immunohistochemical study on cell block of the second aspiration revealed equal amounts of CD3‐positive and CD20‐positive cells. All these cells on the section tested negative for HHV‐8 through immunohistochemistry and Epstein‐Barr virus by in situ hybridization. Our initial impression was EBL in regression. However, flow cytometric immunophenotyping showed monotypic light chain expression of the gated B‐cells. B‐cell receptor gene rearrangement study showed a clonal result. Furthermore, fluorescence in situ hybridization revealed rearrangement of IGH gene. The diagnosis of the second aspiration was EBL with morphological regression but retained clonal genetic features. The patient passed away one month after diagnosis without chemotherapy. This case illustrated the importance of ancillary studies in confirming the clonal nature of a morphologically regressing EBL.  相似文献   
996.
Hematopoietic cell transplantation (HCT) is a common treatment for many disorders. Albuminuria post-HCT, which may represent endothelial injury or inflammation from graft- versus-host disease, increases the risk of chronic kidney disease and nonrelapse mortality at 1 year. HCT recipients also have abnormal blood pressure (BP) and increased rates of cardiovascular complications. We sought to determine the relationships among albuminuria, endothelial dysfunction, and BP in HCT recipients. Patients age ?≥12 years who underwent their first allogeneic HCT between 2012 and 2015 and survived through day 80 post-HCT were eligible. Peripheral endothelial function was assessed using the EndoPAT2000 device at day 80 along with 24-hour ambulatory BP monitoring (ABPM). Clinical and laboratory data were collected along with a urine sample for calculation of the albumin-to-creatinine ratio. Both logistic and linear regression analyses were used to identify associations between EndoPAT score and clinical variables. Sixty patients (median age, 48 years; range, 14 to 69 years) completed the study. The median EndoPAT score was 2.05 (range, 1.02 to 4.45), and 17 patients (28%) had abnormal endothelial function. Forty-two patients (72%) had ambulatory hypertension (HTN), and 38 (63%) had blunted nocturnal dipping. HTN on ABPM (P?=?.045) and blunted nocturnal dipping (P?=?.04) were associated with a lower EndoPAT score. Albuminuria was not associated with EndoPAT score. There was a lack of agreement between our clinical definition of HTN (office BP and/or use of medications) and ABPM results (P?=?.04). We did not find an association between lower EndoPAT scores and albuminuria, but did find an association between an abnormal nocturnal dip and HTN diagnosed by ABPM. This suggests that albuminuria may reflect local endothelial injury and inflammation rather than a systemic process. Office BP readings do not accurately reflect true BP, suggesting that 24-hour ABPM studies are needed to diagnose and treat HTN appropriately.  相似文献   
997.
Poor graft function (PGF) is a life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is characterized by defective hematopoiesis. Mesenchymal stem cells (MSCs) have been shown to support hematopoiesis, but little is known about the role of MSCs in the pathogenesis of PGF. In the current prospective case-control study, we evaluated whether the number and function of bone marrow (BM) MSCs in PGF patients differed from those in good graft function (GGF) patients. We found that BM MSCs from PGF patients expanded more slowly and appeared flattened and larger, exhibiting more apoptosis and senescence than MSCs from GGF patients. Furthermore, increased intracellular reactive oxygen species, p-p53, and p21 (but not p38) levels were detected in MSCs from PGF patients. Moreover, the ability of MSCs to sustain hematopoiesis was significantly reduced in PGF patients, as evaluated by cell number, apoptosis, and the colony-forming unit–plating efficiency of CD34+ cells. In summary, the biologic characteristics of PGF MSCs are different from those of GGF MSCs, and the in vitro hematopoiesis-supporting ability of PGF MSCs is significantly lower. Although requiring further validation, our study indicates that reduced and dysfunctional BM MSCs may contribute to deficient hematopoiesis in PGF patients. Therefore, improvement of BM MSCs may represent a promising therapeutic approach for PGF patients after allo-HSCT.  相似文献   
998.
Alzheimer’s disease (AD), an age-related neurodegenerative condition, is the most common cause of dementia among the elder people, but currently there is no treatment. A number of putative pathogenic events, particularly amyloid β peptide (Aβ) accumulation, are believed to be early triggers that initiate AD. However, thus far targeting Aβ generation/aggregation as the mainstay strategy of drug development has not led to effective AD-modifying therapeutics. Oxidative damage is a conspicuous feature of AD, but this remains poorly defined phenomenon and mechanistically ill understood. The TRPM2 channel has emerged as a potentially ubiquitous molecular mechanism mediating oxidative damage and thus plays a vital role in the pathogenesis and progression of diverse neurodegenerative diseases. This article will review the emerging evidence from recent studies and propose a novel ‘hypothesis’ that multiple TRPM2-mediated cellular and molecular mechanisms cascade Aβ and/or oxidative damage to AD pathologies. The ‘hypothesis’ based on these new findings discusses the prospect of considering the TRPM2 channel as a novel therapeutic target for intervening AD and age-related dementia.  相似文献   
999.
Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a frequent and severe chronic disease drastically impairing life quality. The underlying pathomechanism is incompletely understood yet but there is convincing evidence that in at least a subset of patients ME/CFS has an autoimmune etiology. In this review, we will discuss current autoimmune aspects for ME/CFS. Immune dysregulation in ME/CFS has been frequently described including changes in cytokine profiles and immunoglobulin levels, T- and B-cell phenotype and a decrease of natural killer cell cytotoxicity. Moreover, autoantibodies against various antigens including neurotransmitter receptors have been recently identified in ME/CFS individuals by several groups. Consistently, clinical trials from Norway have shown that B-cell depletion with rituximab results in clinical benefits in about half of ME/CFS patients. Furthermore, recent studies have provided evidence for severe metabolic disturbances presumably mediated by serum autoantibodies in ME/CFS. Therefore, further efforts are required to delineate the role of autoantibodies in the onset and pathomechanisms of ME/CFS in order to better understand and properly treat this disease.  相似文献   
1000.
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