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Although considerable progress has been made in improving the blood service system in China over the last 2 decades, many challenges remain. A number of issues have received public attentions; however, others continue to be underacknowledged and controversial. This article describes 3 of these important and less emphasized issues: first, the ambiguity of the definition of voluntary nonremunerated blood donation and its relationship to an adequate blood supply; second, the current inadequacies of cost recovery from the blood service system; and third, the lack of a universally implemented program of hemovigilance. Currently, there is controversy regarding these challenges. Open recognition and discussion offers the prospect of bringing solutions closer to reality.  相似文献   
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The safety of steviol glycoside sweeteners has been extensively reviewed in the literature. National and international food safety agencies and approximately 20 expert panels have concluded that steviol glycosides, including the widely used sweeteners stevioside and rebaudioside A, are not genotoxic. However, concern has been expressed in recent publications that steviol glycosides may be mutagenic based on select studies representing a small fraction of the overall database, and it has been suggested that further in vivo genotoxicity studies are required to complete their safety profiles. To address the utility of conducting additional in vivo genotoxicity studies, this review evaluates the specific genotoxicity studies that are the sources of concern, and evaluates the adequacy of the database including more recent genotoxicity data not mentioned in those publications. The current database of in vitro and in vivo studies for steviol glycosides is robust and does not indicate that either stevioside or rebaudioside A are genotoxic. This, combined with a lack of evidence for neoplasm development in rat bioassays, establish the safety of all steviol glycosides with respect to their genotoxic/carcinogenic potential.  相似文献   
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Vascular smooth muscle cells (VSMCs) are the major cell type in blood vessel walls, and their proliferation and migration play important roles in the development of atherosclerosis. Recently, it has been reported that IL-1β mediates the inflammatory response through the upregulation of the P2Y2 receptor (P2Y2R). Thus, we examined the role of P2Y2R in IL-1β-mediated proliferation and migration of VSMCs and the underlying molecular mechanisms. VSMCs were pretreated with IL-1β for 24 h to upregulate P2Y2R expression. The cells were then stimulated with UTP or ATP for the indicated times, and cell proliferation and migration and the related signaling pathways were examined. The equipotent P2Y2R agonists ATP and UTP enhanced proliferation, RAGE expression and HMGB1 secretion in IL-1β-pretreated VSMCs. Additionally, pretreatment with IL-1β enhanced UTP-mediated VSMC migration and MMP-2 release, but these effects were not observed in the P2Y2R-siRNA- or RAGE-siRNA-transfected VSMCs. Next, the signaling molecules involved in P2Y2R-mediated cell proliferation and migration were determined. The ERK, AKT, PKC, Rac-1 and ROCK2 pathways were involved in UTP-induced cell proliferation and migration, MMP-2 and HMGB1 secretion and RAGE expression in the IL-1β-pretreated VSMCs. UTP induced the phosphorylation of ERK, AKT and PKC and the translocation of Rac-1 and ROCK2 from cytosol to membrane as well as stress fiber formation, which were markedly increased in the IL-1β-pretreated VSMCs but not in the P2Y2R-siRNA-transfected VSMCs. These results demonstrate that pro-inflammatory cytokines associated with atherosclerosis, such as IL-1β, can accelerate the process of atherosclerosis through the upregulation of P2Y2R.  相似文献   
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We have selected a set of single nucleotide polymorphisms (SNPs) with the specific aim of differentiating European and South Asian ancestries. The SNPs were combined into a 23-plex SNaPshot primer extension assay: Eurasiaplex, designed to complement an existing 34-plex forensic ancestry test with both marker sets occupying well-spaced genomic positions, enabling their combination as single profile submissions to the Bayesian Snipper forensic ancestry inference system. We analyzed the ability of Eurasiaplex plus 34plex SNPs to assign ancestry to a total 1648 profiles from 16 European, 7 Middle East, 13 Central-South Asian and 21 East Asian populations. Ancestry assignment likelihoods were estimated from Snipper using training sets of five-group data (three Eurasian groups, East Asian and African genotypes) and four-group data (Middle East genotypes removed). Five-group differentiations gave assignment success of 91% for NW European populations, 72% for Middle East populations and 39% for Central-South Asian populations, indicating Middle East individuals are not reliably differentiated from either Europeans or Central-South Asians. Four-group differentiations provided markedly improved assignment success rates of 97% for most continental Europeans tested (excluding Turkish and Adygei at the far eastern edge of Europe) and 95% for Central-South Asians, despite applying a probability threshold for the highest likelihood ratio above ‘100 times more likely’. As part of the assessment of the sensitivity of Eurasiaplex to analyze challenging forensic material we detail Eurasiaplex and 34-plex SNP typing to infer ancestry of a cranium recovered from the sea, achieving 82% SNP genotype completeness. Therefore, Eurasiaplex provides an informative and forensically robust approach to the differentiation of European and South Asian ancestries amongst Eurasian populations.  相似文献   
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《Vaccine》2018,36(9):1167-1173
Although Enterovirus 71 (EV71) has only one serotype based on serum neutralization tests using hyperimmune animal antisera, three major genogroups (A, B and C) including eleven genotypes (A, B1-B2, and C1-C5) can be well classified based on phylogenetic analysis. Since 1997, large-scale EV71 epidemics occurred cyclically with different genotypes in the Asia-Pacific region. Therefore, development of EV71 vaccines is a national priority in several Asian countries. Currently, five vaccine candidates have been evaluated in clinical trials in China (three C4 candidates), Singapore (one B2 candidate), and Taiwan (one B4 candidate). Overall, the peak viral titers of these 5 vaccine candidates could only reach about 107 TCID50/mL. Moreover, genotypes of these 5 candidates are different from the current predominant genotype B5 in Taiwan and South-Eastern Asia. We adapted a high-growth EV71 genotype B5 (HG-B5) virus after multiple passages and plaque selections in Vero cells and the HG-B5 virus could reach high titers (>108 TCID50/mL) in a microcarrier-based cell culture system. The viral particles were further purified and formulated with alum adjuvant. After two doses of intramuscular immunization in rabbits, the HG-B5 vaccine candidate could induce cross-reactive neutralizing antibodies against the three major EV71 genogroups. In conclusion, a high-growth EV71 virus was successfully adapted in Vero cells and could induce broad spectrum neutralizing antibody titers against three (A, B5, and C4) genotypes in rabbits.  相似文献   
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BackgroundThere is a lack of large-scale data on the clinical and genotype characteristics of homozygous familial hypercholesterolemia (HoFH) patients in Asia.ObjectiveTo define the characteristics of phenotypic and genetic HoFH probands from mainland China.MethodsWe collected data from patients with suspected HoFH from ten clinical hospitals across mainland China from 2003 to 2019. Clinical data and DNA testing were obtained in all patients. The Kaplan-Meier method was used to generate survival curves, and the groups were compared with the log-rank test.ResultsA total of 108 unrelated probands with suspected HoFH (mean age 14.9 years) were included. The three most common variants were W483X (c.1448 G>A), A627T (c.1879 G>A), H583Y (c.1747 C>T). The majority (64.8%) were compound heterozygotes (n = 70), 23 (21.3%) were true HoFH patients. True HoFH showed higher LDL-C levels compared to compound HoFH (16.8±3.6 mmol/L vs. 15.0±3.1 mmol/L, P = 0.022). During follow-up, only 21.2% patients exhibited an LDL-C reduction of more than 50%. Kaplan-Meier analysis showed that the true HoFH probands had significantly worse survival rates compared to other genotype probands (13-year survival; 20.3% vs. 76.7%, respectively; P = 0.016). In addition, true HoFH shows that 2.8-fold (P = 0.022) increase any death and 3.0-fold (P = 0.023) increase cardiovascular death risk in relative to other FH.ConclusionsThis report shows that HoFH has devastating consequences, and that patients are often only diagnosed after they have been exposed to severely elevated LDL-C for years. Systematic screening and early intensive treatment are an absolute requirement for these young individuals with HoFH.  相似文献   
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