ABSTRACT
Objective To Establish a loop-mediated isothermal amplification(LAMP)assay for detection of Salmonella in fecal samples of tree shrews, and report the result of preliminary application of this method. Methods LAMP primers were designed and synthesized according to the conserved sequence of Salmonella specific gene invA (invasive protein gene A). To optimize the reaction time and temperature by setting 10 reaction times(24 to 42 min)and temperature(57℃ to 66℃)and tested its specificity and sensitivity. At the same time, a conventional PCR test was performed to verify and compare with the LAMP assay. 91 fecal samples of wild-derived tree shrews were detected by the LAMP assay. Results The experimental condition was confirmed as 62℃ and 34 min. The sensitivity of Salmonella was 3.36×101CFU/mL, which was 10 to 100 times higher than that of conventional PCR assay. In 10 kinds of intestinal bacteria for LAMP amplification,Salmonella enteritidis and Salmonella paratyphi B were positive,the others were negative. Among the 91 samples of tree shrew fecal samples detected by the LAMP assay, the positive detection rate was 20.88%. The LAMP assay can be completed within 40 min, the result can be observed and judged visually by color changes. Conclusions The LAMP assay established in this study is convenient,rapid,sensitive and specific. It can be used as a rapid measure for large-scale detection of Salmonella in feces of tree shrews.
ABSTRACT
Objective To discuss the association of allele polymorphisms SNP-rs1799724(C>T)in the TNF-αand SNP-rs11559013(G>A)in the ALCAM with HCV chronic infection in Han population in Yunnan province. Methods 434 HCV chronic infectious patients and 444 healthy individuals of Han Chinese population in Yunnan province were recruited. Two single nucleotide polymorphisms(SNPs)in the SNP-rs1799724(C>T) of TNF-αgene and SNP-rs11559013(G>A)of ALCAM gene were determined by real-time TaqMan polymerase chain reaction. We evaluated the associations of the two SNPs with HCV chronic infection. Results The distributions of allele and genotype of SNP-rs1799724(C>T)in the TNF-αand SNP-rs11559013(G>A)in the ALCAM between hepatitis C virus(HCV)chronic infectious patients and the healthy controls were not statistically significant(P > 0.05). Conclusion SNP-rs1799724(C>T)in the TNF-αand SNP-rs11559013(G>A) in the ALCAM have no association with HCV chronic infection in the Han population in Yunnan province.
ABSTRACT
<p><b>OBJECTIVE</b>To assess the association of single nucleotide polymorphisms (SNPs) of the low molecular weight polypeptide (LMP) gene with chronic hepatitis C virus (HCV) infection among ethnic Han population from Yunnan.</p><p><b>METHODS</b>A total of 427 patients with chronic HCV infection and 412 healthy controls were recruited. SNPs rs1351383, rs17587 and rs2127675 from the promoter region of the LMP2 gene and rs2071543 from the promoter region of the LPM7 gene were genotyped using a TaqMan probe. The haplotypes were constructed. Frequencies of various alleles, genotypes and haplotypes of the selected SNPs were calculated, and their association with chronic HCV infection was analyzed.</p><p><b>RESULTS</b>The frequencies of rs1351383 and rs2127675 alleles of the LMP2 gene, as well as the A-G-A and C-G-G haplotypes of the rs1351383/rs17587/rs2127675 loci, had differed significantly between the two groups (P<0.05).</p><p><b>CONCLUSION</b>The C allele of the rs1351383 locus and G allele of the rs2217675 locus of the LMP2 gene may be susceptible factors for chronic HCV infection among ethnic Han people from Yunnan. The A-G-A haplotype of the rs1351383/rs17587/rs2127675 loci may confer a protective effect, while the C-G-G haplotype may be a susceptible factor for chronic HCV infection in this population.</p>