Efficient enzymatic synthesis of L-ascorbyl palmitate using Candida antarctica lipase B-embedded metal-organic framework.

The Candida antarctica lipase B (CALB) was embedded in the metal-organic framework, zeolitic imidazolate framework-8 (ZIF-8), and applied in the enzymatic synthesis of L-ascorbic acid palmitate (ASP) for the first time. The obtained CALB@ZIF-8 achieved the enzyme loading of 80 mg g-1 with 11.3 U g-1 (dry weight) unit activity, 59.8% activity recovery, and 92.7% immobilization yield. Under the optimal condition, ASP was synthesized with over 75.9% conversion of L-ascorbic acid in a 10-batch reaction. Continuous synthesis of ASP was subsequently performed in a packed bed bioreactor with an outstanding average space-time yield of 58.1 g L-1  h-1 , which was higher than ever reported continuous ASP biosynthesis reactions.

Effects of ischemic preconditioning on the systemic and renal hemodynamic changes in renal ischemia reperfusion injury.

BACKGROUND: Ischemic preconditioning (IPC) could protect against subsequent renal ischemia reperfusion injury (IRI). However, the mechanisms underlying IPC remain far from complete. Hence, we explored the effects of IPC on the renal and systemic hemodynamic changes, renal function and morphology, as well the involvement of endothelial and inducible nitric oxide synthase (eNOS/iNOS), and nitric oxide (NO). METHODS: Male Sprague-Dawley rats were randomly divided into five groups after right-side nephrectomy: Sham group (surgery without vascular clamping); IRI group (the left renal artery was clamped for 45 min); IPC group (pretreated with 15 min of ischemia and 10 min of reperfusion); IPC + vehicle group (administrated with 0.9% saline 5 min before IPC); and IPC + N(G)-nitro-L-arginine methylester (L-NAME) group (pretreated with L-NAME 5 min prior to IPC). The renal and systemic hemodynamic parameters, renal function and morphology, as well as eNOS, iNOS, and NO expression levels in the kidneys were measured at the indicated time points after reperfusion. RESULTS: IPC rats exhibited significant improvements in renal function, morphology, and renal artery blood flow (RABF), without obvious influence on the systemic hemodynamics and renal vein blood flow. Increased eNOS, iNOS, and NO expression levels were detected in the kidneys of IPC rats 24 h after reperfusion. Furthermore, the beneficial effects were fully abolished by the administration of L-NAME. CONCLUSIONS: The results suggest that IPC contributes to early restoration of RABF, probably through eNOS/iNOS-mediated NO production, thereby alleviating the renal dysfunction and histological damage caused by IRI.

Effect of high-dose erythropoietin on graft function after kidney transplantation: a meta-analysis of randomized controlled trials.

PURPOSE: Current evidence suggests that preconditioning with erythropoietin (EPO) can protect against ischemia reperfusion injury in rodents. However, randomized controlled trials (RCTs) assessing the efficacy and safety of high-dose EPO in kidney transplantation have yielded inconclusive results. Herein, we performed a meta-analysis of RCTs to assess whether the administration of high-dose EPO can improve graft function and the potential adverse events. METHODS: Relevant RCT studies that investigated high-dose EPO on graft function after kidney transplantation were comprehensively searched in Pubmed, Embase, and Cochrane Library until July 10, 2014. All statistical analyses were performed using Review Manager 5.0 and STATA 12.0. RESULTS: A total of 4 RCTs involving 356 patients were identified. Comprehensively, a trend of reduction in the incidence of delayed graft function could be observed in the EPO group (EPO vs. placebo groups: RR=0.88); however, the result did not reach the significance level (95% CI, 0.72-1.08; P=0.21). Furthermore, no significant difference in the incidences of adverse events was observed between the two groups. CONCLUSIONS: The current meta-analysis indicates that the administration of high-dose EPO is, to some extent, prone to protect kidney function without increasing the susceptibility to adverse events.

Circulating endothelial progenitor cell: a promising biomarker in clinical oncology.

Human cancers are endowed with sustained vascularization capability, and their growth, invasion, and metastasis are vascularization dependent. Recently, accumulated body of evidence suggests that endothelial progenitor cells (EPCs) can support vasculogenesis and induce angiogenesis through paracrine mechanisms. In addition, numerous clinical studies have revealed the increase in the number of EPCs in the peripheral blood of cancer patients and demonstrated the correlation of circulating EPCs (CEPCs) with the clinical outcomes. This review highlights current enrichment procedures and methods for the detection of CEPCs and different biomarkers to identify CEPCs as well as the functions of EPCs in tumor vascularization. Furthermore, we systematically review available studies on the clinical relevance of CEPCs in cancer patients to explore the potential diagnostic and prognostic values of CEPCs. Although several contrasting results exist, CEPCs can conceivably serve as a promising biomarker for the early diagnosis, prognosis prediction, and treatment response indication in the future. Additionally, further well-designed clinical studies with larger sample size and unique, specific enumeration procedures are warranted to achieve further insight into the clinical implications of CEPCs.