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61.
Xiao-Jie Li Rie Uenishi Saiki Hase Huanan Liao Tee Kok Keng Shigeru Kusagawa Yutaka Takebe 《中国病毒学》2007,22(6):426-433
The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS.
Close to a million of people has been infected and a half million people died of AIDS annually in Asia, becoming the second
largest epicenter of global AIDS epidemic. Molecular epidemiology has been useful tool to track a course of HIV spread. In-depth
knowledge from the studies on molecular epidemiology elucidates the dynamics of HIV spread and the interrelationship of epidemics
in the different regions in Asia.
Foundation items: Grant support from Ministry of Health, Labour and Welfare and Ministry of Education, Science and Technology
in Japan; Japanese Foundation for AIDS Prevention. 相似文献
62.
63.
Transformation of group A streptococci by electroporation 总被引:1,自引:0,他引:1
Abstract The introduction, via electroporation, of free plasmid DNA into three strains of Streptococcus pyogenes is described. The method is very simple and rapid and efficiencies vary from 1 × 103 to 4 × 104 per μg of DNA. The method was also used to introduce an integrative plasmid and transformants were obtained, albeit at a somewhat lower frequency (2 × 102 ). Some of the plasmids used in this study are derivatives of the Lactococcus lactis subsp. cremoris Wg2 plasmid pWV01. These broad host range vectors replicate in Gram-positives as well as Gram-negatives (viz. Escherichia coli ). Here we show that they also replicate in S. pyogenes and S. sanguis . 相似文献
64.
65.
The copper(ii) complexes of two salicylaldehyde semicarbazones, HOC(6)H(4)CH[double bond, length as m-dash]N-NHCONR(2) [H(2)Bnz(2) (R = CH(2)Ph) and H(2)Bu(2) (R = Bu)], were evaluated for their DNA binding and cleavage properties by spectrophotometric DNA titration, ethidium bromide displacement assay and electrophoretic mobility shift assay. Results showed that the Cu(ii) complexes can bind to DNA via a partial intercalation mode with binding constants of 1.1 × 10(4) and 9.5 × 10(3) M(-1) for [Cu(HBnz(2))Cl] and [Cu(HBu(2))Cl], respectively. These complexes also cleave DNA in the presence of ascorbic acid, most likely through hydroxyl radicals that are generated via the reduction of a Cu(ii) to a Cu(i) species. The complexes show similar DNA cleavage activity, which is reflected in the similarity of their frontier molecular orbital energies calculated by density functional theory. These results are discussed in relation to the anticancer properties of the complexes. 相似文献
66.
Yan Yan Chen Jin Ping Wang Ya Yun Jiang Hui Li Ying Hua Hu Kok Onn Lee Guang Wei Li 《PloS one》2015,10(6)
Background
The association between hyperinsulinemia and obesity is well known. However, it is uncertain especially in childhood obesity, if initial fasting hyperinsulinemia predicts obesity, or obesity leads to hyperinsulinemia through insulin resistance.Objective
To investigate the predictive effect of fasting plasma insulin on subsequent weight change after a 5-year interval in childhood.Methods
424 Children from Da Qing city, China, were recruited at 5 years of age and followed up for 5 years. Blood pressure, anthropometric measurements, fasting plasma insulin, glucose and triglycerides were measured at baseline and 5 years later.Results
Fasting plasma insulin at 5 years of age was significantly correlated with change of weight from 5 to 10 years (ΔWeight). Children in the lowest insulin quartile had ΔWeight of 13.08±0.73 kg compare to 18.39±0.86 in the highest insulin quartile (P<0.0001) in boys, and similarly 12.03±0.71 vs 15.80±0.60 kg (P<0.0001) in girls. Multivariate analysis showed that the predictive effect of insulin at 5 years of age on subsequent weight gain over 5 years remained statistically significant even after the adjustment for age, sex, birth weight, TV-viewing time and weight (or body mass index) at baseline. By contrast, the initial weight at 5 years of age did not predict subsequent changes in insulin level 5 years later. Children who had both higher fasting insulin and weight at 5 years of age showed much higher levels of systolic blood pressures, fasting plasma glucose, the homeostasis model assessment for insulin resistance (HOMA-IR) and triglycerides at 10 years of age.Conclusions
Fasting plasma insulin at 5 years of age predicts weight gain and cardiovascular risk factors 5 year later in Chinese children of early childhood, but the absolute weight at 5 years of age did not predict subsequent change in fasting insulin. 相似文献67.
Cloning and expression of a Streptococcus cremoris proteinase in Bacillus subtilis and Streptococcus lactis. 总被引:1,自引:9,他引:1 下载免费PDF全文
Previously, curing experiments suggested that plasmid pWV05 (17.5 megadaltons [Md]) of Streptococcus cremoris Wg2 specifies proteolytic activity. A restriction enzyme map of pWV05 was constructed, the entire plasmid was subcloned in Escherichia coli with plasmids pBR329 and pACYC184. A 4.3-Md HindIII fragment could not be cloned in an uninterrupted way in E. coli but could be cloned in two parts. Both fragments showed homology with the 9-Md proteinase plasmid of S. cremoris HP. The 4.3-Md HindIII fragment was successfully cloned in Bacillus subtilis on plasmid pGKV2 (3.1 Md). Crossed immunoelectrophoresis of extracts of B. subtilis carrying the recombinant plasmid (pGKV500; 7.4 Md) showed that the fragment specifies two proteins of the proteolytic system of S. cremoris Wg2. PGKV500 was introduced in a proteinase-deficient Streptococcus lactis strain via protoplast transformation. Both proteins were also present in cell-free extracts of S. lactis(pGKV500). In S. lactis, pGKV500 enables the cells to grow normally in milk with rapid acid production, indicating that the 4.3-Md HindIII fragment of plasmid pWV05 specifies the proteolytic activity of S. cremoris Wg2. 相似文献
68.
69.
Association of GNLY Genetic Polymorphisms with Chronic Liver Disease in a Korean Population 总被引:1,自引:0,他引:1
Granulysin (GNLY) is found in cytotoxic granules of cytolytic T lymphocytes and natural killer (NK) cells, which are critical for hepatitis B virus (HBV) clearance. GNLY cytotoxicity plays an important role in the defense against viruses or intracellular bacteria. We hypothesized that genetic variation in the GNLY gene could affect the resistance of hosts against HBV infection. We compared the distribution frequencies of GNLY polymorphisms between an HBV-induced chronic liver disease (CLD) group and a spontaneous recovery (SR) control group to determine whether GNLY polymorphisms play a role in HBV clearance. A total of 117 patients in the SR group and 230 patients in the CLD group were enrolled. Samples derived from complex infections, including hepatitis C and human immunodeficiency virus, and those associated with insufficient clinical information (10 samples in SR and 24 samples in CLD) were excluded from the study. The final analysis included 107 SR and 206 CLD samples. DNA was extracted from peripheral blood, and GNLY genotypes were determined by the GoldenGate(?) method. The genotype distribution of the single-nucleotide polymorphisms (SNPs) rs2886767 (C>T), rs1561285 (G>C), and rs11127 (T>C) were significantly different between the SR and CLD groups in a recessive model (p<0.015). These three SNPs were in a complete linkage disequilibrium (LD) block. Diplotype distributions of haplotype (HT) 1 (C-G-T) and HT2 (T-C-C) were significantly different between the SR and CLD groups in a recessive model (p=0.025) and a dominant model (p=0.008). All p-values remained significant after multiple comparisons. GNLY polymorphism genotypes and diplotypes were associated with the chronicity of HBV. These data suggested that genetic variation of GNLY may be an important factor in HBV clearance through the CD8+ T or NK cell-mediated removal of HBV-infected cells from the host. 相似文献
70.
A Bacillus subtilis strain was constructed that contained the repA gene of the lactococcal plasmid pWVO1 in its chromosome. This strain was used to construct the pWVO1-based integration vector pINT1, which lacked the repA gene. The 3.6-kb plasmid pINT1 was not able to replicate in Lactococcus lactis MG1363 but integrated into the chromosome via a Campbell-like mechanism when a lactococcal chromosomal DNA fragment was incorporated in the plasmid. Transformants were obtained that carried between one and four plasmid copies, in stable tandem arrangement on the chromosome. The results indicate that pWVO1 can be used for the development of a Campbell-like integration system fully derived of lactococcal DNA, with which stable multiple copies of any gene of interest can be generated in the lactococcal chromosome. 相似文献