Study progress of role of Toll-like receptor 9 in pathogenesis of viral myocarditis / 中华实用儿科临床杂志

Toll - like receptors represents the first line of defense against foreign pathogens and play an essen-tial role in the innate immune response. Toll - like receptor 9(TLR9)is a major receptor mediating CpG DNA signal transduction,which can not only resist inflammation but also induce inflammatory damage. Studies show that the activa-tion of TLR9 which mediated by endogenous nucleic acid released during viral myocarditis (VMC)can cause the heart damage and be involved in the process of VMC. Further study on the role of TLR9 signal in VMC will provide a theoreti-cal foundation for further revealing the pathogenesis of VMC and seeking effective treatment.

Analysis on association between polymorphism of CD14 and IL-8 gene and susceptibility of necrotizing enterocolitis / 吉林大学学报(医学版)

Objective:To investigate the relationship between the gene polymorphism cluster of differentiation 14 (CD14)-159C/T (rs2569190),and interleukin-8 (IL-8)-251A/ T (rs4073)and the susceptibility of necrotizing enterocolitis (NEC),to clarify the influencing factors of susceptibility of NEC and to provide genetics theory basis for the research on the pathogenesis of NEC. Methods:Total 28 newborns with NEC and 41 newborns without NEC were selected.The amplification of peripheral blood DNA was conducted by PCR.The genotypic and allelic frequencies of CD14-159C/T and IL-8-251A/T of the patients were detected by Sanger DNA sequencing method. The relationship between them and the susceptibility of NEC was studied.Results:The distribution of genotypic frequencies of CD14-159C/T and IL-8-251A/T was consistent with Hardy-Weinberg equilibrium (P >0.05).There were no significant differences of the allelic and genotypic frequencies of CD14-159C/T,or genotypic frequencies of IL-8-251A/T between two groups (P >0.05).While in NEC group,the T allelic frequency of IL-8-251A/T site was higher than that in control group (χ2 = 4.184, P = 0.041, OR = 2.14, 95% CI: 1.03 - 4.46 ). Conclusion:The polymorphism of CD14-159C/T is irrelevant to the pathogeny of NEC,but T allelic frequency of IL-8-251A/T site might be related to the susceptibility of NEC.So T allele in IL-8-251A/T may be one of the danger factors of NEC.

Establishment and evaluation of detection method of bifidobacteria in human fecal using real-time fluorescence quantitative PCR / 吉林大学学报(医学版)

Objective To establish the real-time fluorescence quantitative PCR method for the detection of bifidobacteria in human fecal samples, and to provide an effective means for measuring intestinal bacteria. Methods Total DNA of bacteria was extracted from 60 cases of children's fecal samples. Three primers of bifidobacteria based on the 16S ribosomal RNA (16SrRNA)which possessed specialities of bacteria as amplified region were designed.The part of amplified 16SrRNA gene sequences was used as standard production.The serial dilution of standard was analyzed to build an absolute quantitative standard curve with SYBR GreenⅠ dye method, and the bifidobacterium contents in sixty human fecal samples were calculated. The sensitivity of the reaction was calculated by detecting the lowest detectable standard which determined the sensitivity of the reaction. The PCR products’melting curve was used to evaluate the specificity.The coefficient of variation (CV)of different batches of standard with the same concentration was used to evaluate the stability of reaction.Results The length of PCR product fragment which was used to build the standard curve was about 6 1 3 bp, the sequencing result was consist with the goals, and the standard sample of bifidobacteria was successfully established in real-time fluorescence quantitative PCR.The standard curve showed a good linear relationship with R2=0.999.The minimum detection value was 1.48×102 copies per reaction.The melting curve of real-time fluorescence quantitative PCR was a single peak.The test samples were batched and then examined by fluorescence quantitative PCR.The CV of standards’ Ct values which calculated from the standard (1.48 × 103 -1.48 × 107 copies · μL-1 )were 2.94%, 3.39%, 3.54%,3.08%,and 3.34%,respectively.The contents of bifidobacteria in fecal from 60 children was 7.77± 0.86(copies · g-1 wet fecal)transformed by logarithmic.Conclusion The established real-time fluorescence quantitative PCR method has high sensitivity, strong specificity and good repeatability, which is suitable for detection of human fecal bifidobacteria content.