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991.
To test the purported immune privilege of embryonic stem cells (ESC) in the challenging setting of xenotransplantation, 14 immunocompetent baboons were subjected to a coronary artery occlusion-reperfusion sequence and, two weeks later, randomized to receive in-scar injections of culture medium or cardiac-committed mouse ESC engineered to express fluorescent reporter genes driven by cardiac-specific promoters. Two months after transplantation, left ventricular function, as assessed by echocardiography, deteriorated to a similar extent in control and treated baboons. This correlated with failure to identify the grafted cells by X-gal histology and immunofluorescence. Rejection did not seem to be mediated by xenoantibodies, but rather by T lymphocytes and natural killer cells as suggested by positive immunostaining for CD3 and CD56 early after transplantation. There was no increase in circulating levels of regulatory T cells. These data raise a cautionary note about the immune privilege of ESC and suggest that from a mere immunologic standpoint, ESC xenotransplantation is likely to be an unrealistic challenge.  相似文献   
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Angiofollicular lymphoid hyperplasia (Castleman's disease) is a lymphoproliferative process thought to be mediated by overexpression of II interleukin-6. Castleman's disease has two variants: Castleman's disease has two variants: Hyaline vascular type and plasma cell variant (multicentric Castleman's disease). The hyaline vascular type tends to be localized, and the plasma cell variant shows more systematic signs and carriers a worse clinical prognosis. Castleman's disease is associated with B-cell lymphoma, Kaposi sarcoma, Human herpes virus 8 (HHV-8), and Epstein-Barr virus. Castleman's disease have been described thrice post kidney transplant. In this report, we document the course of a renal recipient who developed the plasma cell variant of Castleman's disease at 16 months after failure of his allograft and return to dialysis. He displayed clinical resolution of this complication after graft nephrectomy. To our knowledge, this is the first case where the disease manifestations disappeared after graft removal. Our patient experienced chronic renal allograft rejection which may have driven all the systematic manifestations of multicentric castleman's disease and possibly reactivated a latent HHV-8 infection. In this case immunohistochemical testing for HHV-8 was not available to prove a role for this agent.  相似文献   
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BACKGROUND: The effect of islet cell transplantation (ICT) on renal function in type 1 diabetes is uncertain and some recent studies report a significant decline in estimated glomerular filtration rate (GFR) and worsening of albuminuria. METHODS: We are conducting a prospective crossover study comparing medical treatment with islet transplantation on the progression of diabetic complications, including renal function. The primary endpoint is change in GFR measured by Tc-diethylenetriaminepentaacetate with secondary endpoints including estimated GFR and albumin excretion. RESULTS: We have followed 21 patients after islet transplantation a median of 29 months (range 13-45) and compared their results with medically treated patients followed a median 29.5 months (range 13-56). There is no difference in the rate of decline in measured GFR between medically treated patients (-0.35+/-0.89; 95% CI: -0.57 to -0.13 mL/min/month/1.73 m) and those after ICT (-0.31+/-1.18; 95% CI: -0.61 to -0.01) and neither is significantly different from that expected for the general population. The rate of decline in our estimated GFR results is lower than that reported in other studies and we did not find any worsening of albuminuria. CONCLUSIONS: We do not find evidence of worsening of renal function after islet transplantation compared with medically treated patients.  相似文献   
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PKDCC encodes a component of Hedgehog signalling required for normal chondrogenesis and skeletal development. Although biallelic PKDCC variants have been implicated in rhizomelic shortening of limbs with variable dysmorphic features, this association was based on just two patients. In this study, data from the 100 000 Genomes Project was used in conjunction with exome sequencing and panel-testing results accessed via international collaboration to assemble a cohort of eight individuals from seven independent families with biallelic PKDCC variants. The allelic series included six frameshifts, a previously described splice-donor site variant and a likely pathogenic missense variant observed in two families that was supported by in silico structural modelling. Database queries suggested that the prevalence of this condition is between 1 of 127 and 1 of 721 in clinical cohorts with skeletal dysplasia of unknown aetiology. Clinical assessments, combined with data from previously published cases, indicate a predominantly upper limb involvement. Micrognathia, hypertelorism and hearing loss appear to be commonly co-occurring features. In conclusion, this study strengthens the link between biallelic inactivation of PKDCC and rhizomelic limb-shortening and will enable clinical testing laboratories to better interpret variants in this gene.  相似文献   
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Journal of Natural Medicines - In diabetes, interactions between AGEs (advanced glycation end products) and RAGEs (receptors of AGEs) are responsible for chronic complications and the current work...  相似文献   
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