Distributive characteristics of HBV DNA CpG islands in HBsAg positive mothers and its relationship with intrauterine transmission / 中华流行病学杂志

Objective: To investigate the type, length, and CG loci of HBV DNA CpG islands in HBsAg positive maternal C genotype and its relationship with intrauterine HBV transmission, so as to provide a new perspective for the study of intrauterine transmission of HBV. Methods: From June 2011 to July 2013, HBsAg-positive mothers and their newborns who delivered in the obstetrics and gynecology department of the Third People's Hospital of Taiyuan were collected. Epidemiological data were collected through face-to-face questionnaires and electronic medical records. Serum HBV markers and serum HBV DNA were detected by electrochemiluminescence and quantitative fluorescence PCR, respectively. Intrauterine transmission of HBV was determined by positive HBsAg and/or HBV DNA in femoral venous blood before injection of HBV vaccine/Hepatitis B immunoglobulin within 24 h of birth. A total of 22 mothers and their newborns with HBV DNA load ≥106 IU/ml in intrauterine transmission were selected as the intrauterine transmission group, and 22 mothers with HBV DNA load ≥106 IU/ml without intrauterine transmission were chosen as the control group by random seed method. The distribution prediction of CpG islands of HBV DNA in 39 mothers with genotype C by HBV DNA sequencing was analyzed. Results: Among 39 mothers with HBV C genotype, 19 were in the intrauterine transmission group, and 20 were in the control group. The HBV DNA of 39 patients with genotype C traditional CpG island Ⅱ and Ⅲ, while the control group had traditional CpG island Ⅰ and novel CpG island Ⅳ and Ⅴ. The length of CpG island Ⅱ and Ⅲ and the number of CG loci of CpG island Ⅱ in the intrauterine transmission group differed from those in the control group (P<0.05). The CpG island Ⅱ length ≥518 bp and the number of CG loci ≥40 in the intrauterine transmission group (11/19) were significantly higher than those in the control group (2/20) (P<0.05). The length of CpG island Ⅱ and the number of CG loci in the X gene promoter region (Xp region) were higher than those in the control group (P<0.05). In the HBV intrauterine transmission group, most of maternal (12/19) HBV DNA CpG island Ⅱ completely covered the Xp region, which was significantly higher than that in the control group (5/20), and the number of HBV DNA Xp region CG loci was higher than that in the control group (P<0.05). Conclusions: The distribution of maternal C genotype HBV DNA CpG islands is related to intrauterine transmission. The length of CpG island Ⅱ and the number of CG sites may increase the risk of intrauterine transmission of HBV.

Analysis on influencing factors of HBV intrauterine transmission based on integration of decision tree model and logistic regression model / 中华流行病学杂志

Objective: To investigate the influencing factors of HBV intrauterine transmission and their interaction effects by integrating logistic regression model and Chi-squared automatic interaction detector (CHAID) decision tree model. Methods: A total of 689 pairs of HBsAg-positive mothers and their neonates in the obstetrics department of the Third People's Hospital of Taiyuan from 2007 to 2013 were enrolled, and the basic information of mothers and their neonates were obtained by questionnaire survey and medical record review, such as the general demographic characteristics, gestational week and delivery mode. HBV DNA and HBV serological markers of the mothers and newborns were detected by fluorescence quantitative PCR and electrochemiluminescence immunoassay respectively. The CHAID decision tree model and unconditional logistic regression analysis were used to explore the factors influencing HBV intrauterine transmission in neonates of HBsAg-positive mothers. Results: Among the 689 neonates, the incidence of HBV intrauterine transmission was 11.47% (79/689). After adjusted for confounding factors, the first and second logistic multivariate analysis showed that cesarean delivery was a protective factor for HBV intrauterine transmission (OR=0.25, 95%CI: 0.14-0.43; OR=0.27, 95%CI: 0.15-0.46); both models indicated that maternal HBeAg positivity and HBV DNA load ≥2×105 IU/ml before delivery were risk factors of HBV intrauterine transmission (OR=3.89, 95%CI: 2.32-6.51; OR=3.48, 95%CI: 2.12-5.71), respectively. The CHAID decision tree model screened three significant factors influencing HBV intrauterine transmission, the most significant one was maternal HBeAg status, followed by delivery mode and maternal HBV DNA load. There were interactions between maternal HBeAg status and delivery modes, as well as delivery mode and maternal HBV DNA load before delivery. The rate of HBV intrauterine transmission in newborns of HBeAg-positive mothers by vaginal delivery increased from 19.08% to 29.37%; among HBeAg-positive mothers with HBV DNA ≥2×105 IU/ml, the rate of HBV intrauterine transmission increased to 33.33% in the newborns by vaginal delivery. Conclusions: Maternal HBeAg positivity,maternal HBV DNA ≥2×105 IU/ml and vaginal delivery could be risk factors for HBV intrauterine transmission in newborns. Interaction effects were found between maternal HBeAg positivity and vaginal delivery, as well as vaginal delivery and high maternal HBV DNA load. Logistic regression model and the CHAID decision tree model can be used in conjunction to identify the high-risk populations and develop preventive strategies accurately.

Relationship between Maternal PBMC HBV cccDNA and HBV Serological Markers and its Effect on HBV Intrauterine Transmission / 生物医学与环境科学（英文）

OBJECTIVE@#To investigate the relationship between maternal peripheral blood mononuclear cells (PBMC) hepatitis B virus (HBV) covalenty closed circular deoxyribonucleic acid (cccDNA) and other HBV serological markers and its effects on HBV intrauterine transmission.@*METHODS@#We enrolled 290 newborns and their hepatitis B surface antigen (HBsAg) positive mothers. HBV cccDNA in PBMC and HBV DNA in serum were detected by a real-time PCR-TaqMan probe while HBV serological markers were detected with an electrochemiluminescence immunoassay.@*RESULTS@#There was a positive correlation between the levels of PBMC HBV cccDNA and serum HBV DNA and HBeAg (r = 0.436 and 0.403, P < 0.001). The detection rate of pattern A ['HBsAg (+), HBeAg (+), and anti-HBc (+)'] was significantly higher in the PBMC HBV cccDNA positive group than in the control group (χ2 = 48.48, P < 0.001). There was a significant association between HBV intrauterine transmission and PBMC HBV cccDNA (χ2 = 9.28, P = 0.002). In the presence of serum HBV DNA, HBeAg, and PBMC HBV cccDNA, the risk of HBV intrauterine transmission was three times higher (OR = 3.69, 95% CI: 1.30-10.42) than that observed in their absence. The risk of HBV intrauterine transmission was the greatest (OR = 5.89, 95% CI: 2.35-14.72) when both PBMC HBV cccDNA and pattern A were present. A Bayesian network model showed that maternal PBMC HBV cccDNA was directly related to HBV intrauterine transmission.@*CONCLUSION@#PBMC HBV cccDNA may be a direct risk factor for HBV intrauterine transmission. Our study suggests that serological markers could be combined with PBMC-related markers in prenatal testing.

Transformation of Dunaliella salina by using glass beads--a novel transformation method / 生物工程学报

A novel transformation method was firstly established using glass beads in Dunaliella salina (D. salina). The results showed that the GUS gene, a reporter gene, was successfully expressed in D. salina. Cells of D. salina presented blue color under the microscope after stained. In addition, different factors which influenced transformation were optimized including the transformation consecutive time, rotate speed, concentration of the plasmid and PEG 6000. The experiment indicated that this fit together can obtain the best results for D. salina transformation: adding 150 microL PEG and 90 microL plasmid DNA to 800 microL culture of D. salina (10(6) cells/mL) containing 300 mg glass beads, swirling 12 seconds under the rotate speed 2400r/min. This newly method can be used as a potential tool in the research of D. salina gene engineering with the advantage of more simpleness, convenience, quickness and less expense.

Preliminary Study on Transformation of Human canstatin Gene to the Novel Bioreactor——Dunaliella salina / 中国生物工程杂志

The human canstatin cDNA was amplified by RT-PCR and then directionally cloned into pU? expression vector. The recombinant pU?-Can vector was connected with the screening marker (bar box), to construct a eukaryotic expression vector called pU?-Can-Bar. This expression vector was introduced into the D.salina by glass beads method. The screening culture of transformants of D.salina was performed in solid media containing 5 ?g/ml PPT, and the analyses of transformants were carried out through PCR and Southern blot. PCR results revealed that specific 700 bp products were detected in the different transformants of D.salina but not in negative control. Southern blot analysis further demonstrated that human canstatin gene was integrated into the D.salina genome. Moreover, the results of genetic stability analyses of transformants demonstrated that canstatin gene was stably inherited in the D.salina transformants. The successful preparation of the D.salina transformants will provide the experimentation evidence for producing canstatin protein cosmically by using the D.salina bioreactor and give a better prophase work basis for clinic application of canstatin protein early.

Prospect and Progress on Dunaliella salina in the Area of Molecular Biology / 中国生物工程杂志

Unicellular green alga,Dunaliella salina(D.salina),is a biflagellar alga without cell wall,which is a kind of very important eukaryotic microalga.In the previous study,the research of D.salina focus on the morphology,the mechanism of salt tolerance and ?-carotene,however,with the rapid development of microalgal biotechnology,a lot of work about D.salina was reported in recent years.In the area of molecular biology,the studies of D.salina mainly place emphasis on the cloning and analysis of important functional genes,regulatory sequences,and the expression of foreign genes using D.salina as host.The research advance in these aspects were reviewed.