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991.
Renal transplantation in recipients with an ileal conduit is uncommon and occasionally controversial as it has been associated with high morbidity and mortality rates. We report on 17 patients with an ileal conduit who received a deceased donor renal transplant at our institution between January 1986 and December 2012. We retrospectively reviewed their allograft and surgical outcome. There were four mortalities at five, five, 39, and 66 months post‐transplant. Sixteen of 17 grafts functioned immediately; one patient had primary non‐function secondary to vascular thrombosis. Thirteen of 17 (76.5%) grafts were functioning at a mean follow‐up period of 105 months. The mean serum creatinine at follow‐up was 111 μM (±38.62). Five patients had seven episodes of urosepsis requiring hospital admission, and five patients received treatment for renal stone disease. We conclude that given improvements in immunosuppression, surgical technique, infection treatment, and selection criteria, we believe that renal transplantation in the patient with an ileal conduit yields excellent graft survival, although there is a high morbidity rate in this cohort of patients in the long term.  相似文献   
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995.
Many factors influence the long‐term outcome of kidney transplantation, which is defined very schematically by patient death or renal dysfunction leading to graft loss. The most important of these factors is most likely the quality of the transplant itself, with kidneys from living donors showing a positive impact, while kidneys from expanded criteria donors show deleterious impacts. Various clinicopathological scores exist to predict mid‐ to long‐term outcomes and avoid the transplantation of kidneys displaying inferior results. The key factors related to the recipient include their age as well as disease recurrence, HLA matching, HLA immunization, ethnic background, time on dialysis, and cardiovascular comorbidities. Renal function, defined based on estimated GFR and/or proteinuria values, is a result of all these factors. Delayed graft function has a detrimental long‐term impact, as does the level of renal function impairment either in stable condition or in case of progressing dysfunction. Finally, although current immunosuppression regimes are highly efficient in preventing acute rejection, the burden of specific (diabetes, nephrotoxicity) and nonspecific (infection and cancer) side effects has significant negative long‐term consequences that may well be worse in the future because of the increasing ages of both donors and recipients. The development of safer immunosuppression strategies is therefore crucial to improve long‐term outcomes.  相似文献   
996.
Whereas vascularized composite allografts often undergo acute rejections early in the postgraft period, rejection manifesting with severe vascular changes (graft vasculopathy) has only been observed on three occasions in humans. We report a hand‐allografted patient who developed severe rejection following discontinuation of the immunosuppressive treatment. It manifested clinically with erythematous maculopapules on the skin and pathologically with graft vasculopathy that affected both large vessels and smaller cutaneous ones. The observation that graft vasculopathy can affect skin vessels shows that it is amenable to diagnosis with usual skin biopsy as recommended for the follow‐up of these allografts. Graft vasculopathy developing in the setting of vascularized composite allografts likely represents chronic rejection due to under‐immunosuppression and, if confirmed, should be included in a future update of the Banff classification of vascularized composite allograft rejection.  相似文献   
997.
Ruptures of the distal biceps brachii tendon are generally treated operatively due to their loss of supination and flexion force. A mechanical impingement at the insertion of the tendon at the radial tuberosity is discussed to play a role in the etiology of this injury. The aim of this study was to present a detailed, three-dimensional anatomical analysis of the radioulnar space at the radial tuberosity. A total of 166 imprints of the radioulnar space in neutral rotation and pronation from 84 cadaveric specimens of both arms using silicone impression material were produced for this study. Imprints were cut in slices of 3 mm and digitally measured after picture acquisition using a high-resolution digital camera. Distances were grouped into a proximal, central, and distal groups and used for correlation to morphometric data at the elbow (radial head diameter, ulna and radius length) as well as volume calculation. The mean radioulnar distance was 8.8 ± 4.0 mm in neutral rotation and 7.8 ± 3.9 mm in pronation. In pronation, the central zone was the smallest whereas in neutral rotation the proximal zone was the smallest. The volume of the radioulnar space did not reduce significantly during pronation. Little space is provided for the insertion of the distal biceps brachii tendon especially during pronation. This could play a role in the etiology of distal biceps brachii tendon ruptures and should be considered in the fixation after rupture of the tendon. Clin. Anat., 33:661–666, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
998.
《Immunobiology》2020,225(2):151876
Acute graft-versus-host disease (aGVHD) is a severe inflammatory complication of haematopoeitic stem cell transplantation. The nuclear factor- Kappa Beta (NF-κB) signaling pathway regulates T cell activation. The NF-κB controls the expression of microRNA-146a (miR-146a) that in turn regulates NF-κB activation through a negative feedback loop. We aim to analyze the association between NF-κB1 encoding p50 (rs28362491, −94 in.ertion/deletion ATTG) and miR-146a (rs2910164, G > C) polymorphisms and risk of aGVHD. Genotyping was performed for 135 HLA-matched donors using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP).The incidence of aGVHD grades II-IV was 24/135 (17.8 %). NF-κB1 genotype and cytomegalovirus infection were significantly associated with risk of aGVHD II-IV (p = 0.022, HR = 3.17, 95 % CI:1.18-8.51 and p = 0.048, HR = 2.56, 95 % CI:1.01–6.52, respectively). In multivariate analysis, NF-κB1homozygous deletion/deletion genotype was the only independent risk factor associated with aGVHD II-IV (p = 0.013, HR = 3.50, 95 % CI:1.30–9.44). No significant association could be observed between miR-146a polymorphism and aGVHD. Combined NF-κB1 and miR146a genotype analysis warrants investigation in a larger cohort. Our preliminary data do not support the association between miR146a and aGVHD, but suggest an association between NF-κB1 and risk of aGVHD that may pave the way for the development of a novel targeted therapy if proved in a larger cohort.  相似文献   
999.
Antibody-mediated rejections (AMR) in the absence of circulating anti-HLA-DSA have highlighted the role of non-HLA antibodies, particularly those directed against endothelial cells. Of these, MICA (major histocompatibility complex class I chain–related molecule A) antibodies are the most notable and important because of their potential in promoting graft rejections. Limited studies have focused on the impact of MICA donor-specific antibodies (DSA) on graft outcome as compared to those that are not donor-specific (NDSA). We evaluated pre- and post-transplant sera at POD 7, 30, 90, 180 and the time of biopsy from 206 consecutive primary live donor renal transplant recipients for anti-MICA and anti-HLA antibodies using single antigen bead assay on a Luminex platform. Recipients who developed MICA antibodies and their donors were phenotyped for MICA alleles. For the purpose of antibody analysis, patients were categorized into three major groups: biopsy-proven AMR, acute cellular rejection (ACR) and those with no rejection episodes (NRE). During the mean follow-up period of 17.37 ± 6.88 months, 16 of the 206 recipients developed AMR, while ACR was observed in only 13 cases. A quarter (25%) of the AMR cases had anti-MICA antibodies as compared to 7.7% of those experiencing ACR and 6.2% of the NRE group. Allelic typing revealed that all MICA Ab +ve AMR cases were due to the presence of donor-specific antibodies. MICA-DSA even in the absence of HLA-DSA was significantly associated with AMR but not with ACR when compared with the NRE group (P = <.01).  相似文献   
1000.
文题释义:自体块状皮质骨:自体块状皮质骨具有刚性的板层状结构,毛细血管的含量较低,因此移植后很难维持具有活性的成骨细胞或骨祖细胞,致密的矿化基质导致血管重建和长入的速度相对缓慢,但其空间维持能力强,生物相容性好,其中含有的成骨细胞和生长因子对骨再生起促进作用,是骨移植材料的“金标准”。 Onlay植骨:于两侧下颌外斜线处取长方形皮质骨块,在上颌左侧骨缺损区植入皮质骨块,右侧骨缺损区植骨同期植入种植体。 背景:自体骨有骨传导、骨诱导及骨生成的特性,同时具有良好的生物相容性,移植后无排斥反应。但关于自体骨块移植后的骨块是完全被吸收替代?还是能保留细胞活性长期存留?仍存在争议。 目的:观察皮质骨移植后改建再生过程中的组织学变化。 方法:6只健康比格犬麻醉后拔除两侧上颌前磨牙,并去除颊侧宽约10 mm、长约15 mm、厚度约2 mm的骨板,建立上颌骨缺损模型,在双侧下颌骨体颊侧切取相应大小的块状皮质骨并修整边缘。在上颌骨缺损区移植皮质骨块,一侧为单纯块状皮质骨移植,另一侧在块状皮质骨移植同期植入种植体。分别于骨移植后3,6个月取材,进行大体观测和组织学观察,分析移植骨块的吸收率、移植骨中的细胞存活率。实验方案经大连医科大学动物实验伦理委员会批准。 结果与结论:①大体观察可见移植骨块体积逐渐缩小,边缘圆钝,与基骨结合稳固;②6个月时全部种植体脱落;硬组织磨片可见移植骨块与基骨间存在新生骨连接;6个月时移植骨骨陷窝孔隙率明显低于3个月,移植骨吸收率显著高于3个月(均P < 0.05);③结果说明,块状皮质骨移植后,能够与受植区基骨发生骨结合,其内部的骨细胞部分保持活力,随着愈合期延长,新生骨细胞的比例增加,移植骨块的体积逐渐变小。皮质骨移植同期种植后移植物吸收明显,种植体骨结合不良。 ORCID: 0000-0001-5201-9377(王宁) 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程  相似文献   
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