[Effectiveness of the "14 plus 7 day quarantine" and "nucleic acid plus total antibody testing" strategy for screening imported patients with COVID-19 in Xiamen].

Objective: To analysis effectiveness of the "14 plus 7 day quarantine" and "nucleic acid plus total antibody testing" strategy (combined screening strategy) for screenin the imported patients with COVID-19 in Xiamen. Methods: The study populations were overseas travelers arriving in Xiamen from March 17 to December 31, 2020, and overseas travelers who had quarantine outside Xiamen for less than 21 days from July 18 to December 31, 2020. Data were collected and analyzed on the timing of detection, pathways, and test results of the imported patients with COVID-19 after implementing combined screening strategy. Results: A total of 304 imported patients with COVID-19 were found from 174 628 overseas travelers and 943 overseas travelers from other cities. A total of 163 cases (53.6%) were diagnosed by multitime, multisite intensive nucleic acid testing after positive finding in total antibody testing. Among them, 27 (8.9%) were first positive for nucleic acid in 14 plus 7 day quarantine and 136 were first positive for nucleic acid in 14-day quarantine. Only 8 of these individuals were tested positive for nucleic acid after positive total antibody testing. The other 128 individuals were tested positive for nucleic acid after being negative for average 2.3 times (maximum of 6 times). Aditional 155 cases might be detected by using the combined "14 plus 7 day quarantine" and " nucleic acid plus total antibody testing" strategy compared with "14-day quarantine and nucleic acid testing" strategy, accounting for 51.0% of the total inbound infections. So the combined screening strategy doubled the detection rate for imported patients with COVID-19. No second-generation case caused by overseas travelers had been reported in Xiamen as of February 26, 2021. Conclusions: Xiamen's combined screening strategy can effectively screen the imported patients with COVID-19 who were first positive for nucleic acid after 14 day quarantine. Compared with "14 day quarantine and nucleic acid testing", the combined screening strategy improved detection rate and further reduced the risk of the secondary transmission caused by the imported patients with COVID-19.

[Relationship between the HBsAg-positive infection status of mothers and the non/low-response to hepatitis B vaccine of their infants].

Objective: To explore the relationship between the status of HBsAg-positive infection of mothers and the non/low-response to hepatitis B vaccine of their infants. Methods: A total of 225 pairs of mothers and their infants were recruited in our cohort from June 2011 to July 2013. Infants were given three doses of hepatitis B vaccine at hour 24, first month and month 6(t)h respectively and were followed up for one year after birth. HBV serological markers and HBV DNA in the peripheral blood of both mothers and infants were detected by Electro-chemiluminescence immunoassay and fluorescence quantitative Polymerase Chain Reaction. Results: Six HBV infection models were detected in HBsAg-positive mothers, and "HBsAg (+), HBeAg (+), anti-HBc (+)" (model one) and "HBsAg (+), anti-HBe (+), anti-HBc (+)" (model two) accounted for 92.5%(208/225) of all the models. Rate of non/low-response to hepatitis B vaccine in infants born to mothers in model one was lower than those in model two, the differences are statistically significant (χ(2)=4.80, P=0.029). The rate of non/low-response to hepatitis B vaccine in infants showed a downward trend with the rising of HBeAg level in their mothers (χ(2)=4.86, P=0.028). Results from the unconditional logistic regression analysis showed that the HBeAg of the HBsAg-positive mothers was significantly correlated with the low risk of non/low-response to hepatitis B vaccine in infants (OR=0.598, 95%CI: 0.378-0.947). The positive rate of serum HBV DNA in HBsAg-positive mothers was 54.2%, while the rate of non/low-response to hepatitis B vaccine in infants born to HBV DNA positive mothers was similar to those infants born to HBV DNA negative mothers (χ(2)=0.22, P=0.640). Conclusions: "HBsAg (+), HBeAg (+), anti-HBc (+)" and "HBsAg (+), anti-HBe(+), anti-HBc (+)" were the common models seen in HBsAg-positive mothers, and the rate of non/low-response to hepatitis B vaccine was different between the two models. HBeAg of HBsAg-positive mothers might have positive effects on the immune response to hepatitis B vaccine in infants but the mechanisms remained not clear. HBV DNA of the HBsAg-positive mothers did not seem to be correlated with the immune response to hepatitis B vaccine in infants.

[Influencing factors for non/low-response to hepatitis-B vaccine in infants of HBsAg positive mothers].

Objective: To investigate the influencing factors for non/low-response to hepatitis B vaccine in infants of HBsAg-positive mothers. Methods: A total of 286 HBsAg-positive pregnant women and their infants were recruited from the Third People's Hospital of Taiyuan during July 2011 to January 2013. The infants were immunized with hepatitis B vaccine according to the 0-1-6 month vaccination schedule and followed up for 12 months. The serum HBV DNA level of mothers, neonates and infants were detected by electro chemilum inescence immunoassay kits and fluorescene quantiative polymerase chain rection. Results: Among 286 infants, the rate of non/low-response to hepatitis B vaccine was 18.53% (53/286). Non-conditional logistic regression analysis indicated that the mother's HBV DNA level ≥1×10(7) copies/ml (OR=2.592, 95%CI: 1.121-5.996) and natural birth (OR=1.932, 95%CI: 1.021-3.654) were the risk factors for non/low-response to hepatitis B vaccine, the risks were 2.592 times and 1.932 times higher compared with the infants whose mothers were HBV DNA negative and the infants whose mothers had cesarean delivery. There was no multiplicative or additive interaction between high HBV DNA load and natural birth (OR=1.055, 95%CI: 0.209-5.321), (RERI=1.617, 95%CI: -4.038-7.272; AP=0.364, 95%CI: -0.527-1.225; SI=1.195, 95%CI: 0.270-13.135). After stratified analysis of mother's HBV DNA level, delivery mode of mothers was not associated with non/low-response of their infants. Conclusion: The mother's load of HBV DNA≥1×10(7) copies/ml might be the factor for non/low-response to hepatitis B vaccine in infants of HBsAg positive mothers.

[Effect of interleukin-6 and interleukin-12 on immune response to hepatitis B vaccination in infants of HBsAg-positive mothers].

Objective: To explore the effect of interleukin-6 (IL-6) and Interleukin-12 (IL-12) on immune response to hepatitis B vaccination in infants of HBsAg-positive mothers. Methods: A total of 91 neonates whose mothers were HBsAg-positive were included and followed up for 12 months. HBV DNA and HBV serological markers in the peripheral blood of the neonates and infants were detected with fluorescence quantitative polymerase chain reaction (FQ-PCR) and chemiluminescence immunoassay (CLIA), and the levels of IL-6 and IL-12 in the peripheral blood of the neonates and infants were detected with enzyme-linked immunosorbent assay (ELISA). Results: The non-/hypo-response rate to hepatitis B vaccination was 35.16% (32/91) in the 91 infants. In the neonatal period and infantile period, the level of IL-6 in non-/hypo-response group was lower than that in high-response group, while the level of IL-12 was higher than that in high-response group, and there was significant difference (P<0.01). From the neonatal period to the infantile period, the level of IL-6 increased, while the level of IL-12 descended in both groups, and there was significant difference (P<0.01). Furthermore, the level of anti-HBs of infants was positively correlated with the level of IL-6 (r(s)=0.70, 0.79, P<0.01), and was negatively correlated with the level of IL-12 (r(s)=-0.71, -0.72, P<0.01) in the neonatal period and the infantile period. From the neonatal period to the infantile period, the increased level of IL-6 was positively associated with the level of anti-HBs (r(s)= -0.74, P<0.01), while the decreased level of IL-12 was negatively associated with the level of anti-HBs (r(s)=-0.42, P<0.01). The level of IL-6 was negatively correlated with the level of IL-12 in the neonatal period and the infantile period (r(s)=-0.68, -0.70, P<0.01). Conclusions: IL-6 might promote the immune response to hepatitis B vaccination in infants whose mothers were HBsAg-positive, while IL-12 might inhibit the immune response. IL-6 and IL-12 would affect the immune response to hepatitis B vaccination in infants of HBsAg-positive mothers at the same time.

[Effect of telbivudine on infants born to HBsAg-positive mothers with non-/hypo-response to hepatitis B vaccine during their second and third trimesters of pregnancy].

Objective: To explore the effect of telbivudine treatment in a prevention program on infants born to HBsAg-positive mothers with non-/hypo-responsiveness to hepatitis B vaccine. Methods: A retrospective cohort study with a total of 321 HBsAg-positive pregnant women and their infants enrolled, was conducted. The mothers were recruited from the Third People' s Hospital of Taiyuan, from July 2011 to January 2013. According to the situation of telbivudine intake in second and third trimesters of pregnancy, the participants were divided into two groups: with telbivudine-treated or as control. The neonates were followed up till the age of 12 months. Maternal, neonatal and infantile HBV-M together with HBV DNA in serum were measured using the electro-chemiluminescence immuno-assay (ECLIA) kits and fluorescence quantitative polymerase chain reaction (FQ-PCR) assay, respectively. Results: The rate of non-/hypo-response was 17.99%. After adjusting the potential confounding factors, the telbivudine treatment on HBsAg-positive mothers in the second and third trimesters of pregnancy seemed as the protective factor for non-/hypo-response to hepatitis B vaccine in infants (aRR=0.119, 95% CI: 0.014-0.974). Levels of IFN-γ and IL-10 in telbivudine-treated group were higher than those in the controls (aRR=8.684, 95%CI: 1.977-38.140; aRR=5.330, 95% CI: 1.278-22.236). When the serum levels of IFN-γ and IL-10 in neonatal peripheral blood were higher than 228.47 pg/ml and 174.05 pg/ml respectively, the infants were less likely to be non-/hypo-responsive to the hepatitis B vaccine (aRR=0.300, 95%CI: 0.105-0.857) (aRR= 0.104, 95% CI: 0.030-0.354). Conclusion: Telbivudine treatment provided for the HBsAg-positive mothers in second and third trimesters of pregnancy were less likely to develop non-/low-responsive to hepatitis B vaccine in infants since IFN-γ and IL-10 might have played a vital role in this process.

[Relationship between the mode of HBV marker and immune status in neonates and non-/hyporesponse to hepatitis B vaccine].

OBJECTIVE: A prospective study was conducted to explore the influence of neonatal modes of HBV marker (HBVM) on non-/hypo-response to hepatitis B vaccine in infants. METHODS: From July 2011 to July 2013, a total of 386 pregnant women who showed serum HBsAg positive with their neonates at birth and another 227 infants at 12 months admitted in the Third People' s Hospital of Taiyuan in Shanxi province, China. All infants received hepatitis B vaccine with the 0-1-6 month schedule. Maternal, neonatal and infantile HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc were measured by chemiluminescence-immunoassay. The neonatal/infantile PBMC TLR3 expression level and the quantities of T cell subsets, B cells, DCs were measured by Flow Cytometry. The neonatal/infantile Th1/Th2 cytokines were measured by ELISA. RESULTS: Four types of common neonatal modes of HBVM appeared as " HBeAg(+) anti-HBe(+) " , "HBsAg(+)HBeAg (+) anti-HBe(+) " , "HBsAg(+) " and "HBVM(-)" , respectively. The overall rate of non-/hypo-response to hepatitis B vaccine in neonatal mode of " HBeAg(+) anti-HBe(+) " was 5.2%, lower than that seen in the other three types of mode (20.0%, 40.0% and 22.5%, respectively). The frequencies of circulating CD4(+) T cells and CD8(+) T cells were significantly different among four common modes of HBVM in infants. Meanwhile, the level of IL-6 in mode of " HBeAg(+) anti-HBe(+) " was higher than that in the mode of " HBVM(-)" at two points. There was a positive correlation appeared between the level of IL-6 and the level of anti-HBs. It was quite unlikely to show non-/hypo-response to hepatitis B vaccine, when neonates were at the level as IL-6> 1 112.0 pg/ml (OR=0.386, 95% CI: 0.266-0.561, P<0.001). CONCLUSIONS: Neonates who were with the mode of " HBeAg (+) anti-HBe (+) " and high level of IL-6 showed a lower non-/hyporesponse rate on hepatitis B vaccine. It is necessary to further study the relationship between neonatal mode of HBVM and the immune status.

[Effects related to HBeAg status and mode of delivery as well as the interactions on intrauterine transmission among HBsAg-positive mothers].

OBJECTIVE: To investigate the relationship between HBeAg status, mode of delivery and intrauterine transmission of the HBsAg-positive mothers as well as their interactions. METHODS: A total of 344 HBsAg-positive pregnant women and their infants were enrolled in this study. The mothers were recruited from the Third People's Hospital of Taiyuan, from July 2011 to January 2013. Serum HBV-M and HBV DNA were measured using the electro-chemiluminescence immune-assay (ECLIA) kits and fluorescene quantitative polymerase chain reaction (FQ-PCR) assay, respectively. Univariate analysis and unconditional logistic regression analysis were used to explore the risk factors on intrauterine transmission. RESULTS: Among 344 neonates born to HBsAg-positive mothers, 42 were validated as HBV intrauterine transmitted, with the rate of intrauterine transmission as 12.21% (42/344). The rates of intrauterine transmission among HBeAg-positive and HBeAg-negative mothers were 18.52% (30/162) and 6.59% (12/182), respectively. The rates of intrauterine transmission were 22.22% (34/153) and 4.19% (8/191) in the groups of vaginal birth or caesarean delivery, respectively. RESULTS from unconditional logistic regression analysis showed that after adjusting the confounding factors, HBeAg-positive mothers (OR=3.003, 95% CI: 1.368-6.593) and vaginal birth (OR=7.333, 95% CI: 3.108-17.302) might serve as the risk factors for the HBV intrauterine transmission. Data from the interaction analysis showed that there were additive interactions [relative excess risk due to interaction (RERI) as 14.229; the attributable proportion (AP) due to interaction as 0.587; the synergy index (SI) as 2.579] and multiplicative interaction (OR=1.084, 95%CI: 0.720-1.632) between HBeAg status and the modes of delivery. CONCLUSION: Vaginal birth and HBeAg-positive might serve as the risk factors for HBV intrauterine transmission. There also appeared additive interactions between HBeAg status and the mode of delivery.

Changes in the expression of cyclin G2 in esophageal cancer cell and its significance.

This study aimed to analyze the expression, clinical significance of cyclin G2 (CCNG2) in esophageal carcinoma, and the biological effect in its cell line by CCNG2 overexpression. Immunohistochemistry and western blot were used to analyze CCNG2 protein expression in 73 cases of esophageal cancer and normal tissues to study the relationship between CCNG2 expression and clinical factors. CCNG2 lentiviral vector and empty vector were respectively transfected into esophageal cancer Eca-109 cell line. Reverse transcription-polymerase chain reaction and western blot were used to detect the mRNA level and protein of CCNG2. MTT assay and cell cycle were also conducted as to the influence of the upregulated expression of CCNG2 that might be found on Eca-109 cell's biological effect. Immunohistochemistry: The level of CCNG2 protein expression was found to be significantly lower in esophageal cancer tissue than normal tissues (P < 0.05). Western blot: The relative amount of CCNG2 protein in esophageal cancer tissue was respectively found to be significantly lower than in normal tissues (P < 0.05). The level of CCNG2 protein expression was not correlated with gender, age, and tumor size (P > 0.05), but it was correlated with lymph node metastasis, clinic stage, and histological grades (P < 0.05). Loss of CCNG2 expression correlated significantly with poor overall survival time by Kaplan-Meier analysis. The result of the biological function showed that Eca-109 cell-transfected CCNG2 had a lower survival fraction, more percentage of the G0/G1 phases (P < 0.05), and lower cyclin-dependent kinase 2 (CDK2) protein expression. CCNG2 expression decreased in esophageal cancer and correlated significantly with lymph node metastasis, clinic stage, histological grade, and poor overall survival, suggesting that CCNG2 may play important roles as a negative regulator to esophageal cancer cell by promoting degradation of CDK2.

Cloning and characterization of the rpfC gene of Xanthomonas oryzae pv. oryzae: involvement in exopolysaccharide production and virulence to rice.

rpfC is one of a cluster of genes which coordinately regulate the synthesis of extracellular enzymes and exopolysaccharide and pathogenicity in Xanthomonas campestris pv. campestris, the black rot pathogen of brassicas. An rpfC homolog which could functionally complement an rpfC mutant of X. campestris pv. campestris was identified in Xanthomonas oryzae pv. oryzae and the gene was characterized. Mutation of this gene in X. oryzae pv. oryzae had no effect on extracellular enzymes, but exopolysaccharide synthesis and virulence to rice were substantially reduced.

[Multivariate analysis on factors associated with preterm delivery].

In order to estimate the occurrence of Preterm Delivery (PD) and factors associated with PD, 1141 perinatal cases at first affiliated hospital were collected by the method of systematic random sampling. The occurrence rate of PD was 6.0%. Multivariate analysis revealed that the history of premature birth, twin pregnancy, polyhydramnios, placenta praevia, premature rupture of fetal membranes and Bart's fetal hydrops were the main risk factors with statistical significance. Path analysis showed that the history of premature birth had indirect positive effect (elevating risk of PD) on PD through premature rupture of the fetal membranes and Bart's fetal hydrops. Similarly, twin pregnancy had indirect positive effect through premature rupture of the fetal membranes and polyhydramnios. It is suggested that proper health care of the pregnant mother attending to the risk factors should be emphasized to prevent the occurrence of PD.