[Evaluation of effect based on different typing methods in Escherichia coli].

Objective: To evaluate the typing and clinical application effect based on clustered regularly interspaced short palindromic repeats (CRISPRs), serotype, and Multilocus Sequence Typing (MLST). Methods: The spacers, serotype and sequence type (ST) were obtained with CRISPRsFinder, SeroTypeFinder and MLST. PCR was used to amplify the CRISPRs, and the spacers were used to predict serotype and ST, then comparing with the serotype and ST. Results: We defined the I-E CRISPR/Cas as CT-Ⅰ, I-F CRISPR/Cas as CT-Ⅱ, and only CRISPR3-4 as CT-Ⅲ. We designated each unique arrangement spacer profile as a unique CRISPRs type. A total of 79 CT types, 76 serotypes, and 66 STs were identified. The CRISPRs typing was the most discriminating, with the Simpson index of 0.936, having the highest correlation with serology with the adjusted Rand index of 0.908. The CRISPRs type could divide the same serotype (ST) into two subtypes [O157∶H7(ST11), O104∶H4(ST678), and O26∶H11(ST21)]. The detection rates of CRISPR1, CRISPR2, CRISPR3, CRISPR4, and CRISPR3-4 were 81.1%, 94.5%, 1.4%, 1.4%, and 4.6%, with the accuracy rate of 95.0% and 100.0% according to the spacers to forecast O157∶H7 (ST11) and ST131. Conclusion: Based on the CRISPRs spacer, this method can be used as an essential molecular typing for E.coli, as it presents a good typing and clinical application effect.

[Occurrence and related factors of preterm birth in Guangxi Zhuang Autonomous Region during 2017-2019].

Objective: To investigate the incidence of preterm birth in Guangxi Zhuang Autonomous Region and explore the related factors and their combined effects. Methods: The study subjects were women giving birth to live babies at the monitoring points of critical maternal hospital monitoring system in Guangxi Zhuang Autonomous Region from January 1, 2017 to December 31, 2019. The data of general characteristics (age and marital status), pregnancies (parity, number of previous cesarean delivery, the number of prenatal check and number of fetuses in this pregnancy) and disease conditions (placenta previa, placental abruption, hypertension, diabetes, anemia, and heart disease) were collected, and the incidence of preterm birth were calculated according to the definition of preterm birth set by WHO and China, respectively. Logistic regression model was used to explore the factors associated with premature birth and their combined effects. Results: According to definitions of WHO and China, the cumulative incidence of preterm birth in Guangxi from 2017 to 2019 was 7.45% (16 819/225 727) and 7.34% (16 559/225 727), respectively. Advanced age [≤34 years old as reference, OR (95%CI) of 35-39 and ≥40 years old were 1.36 (1.30-1.42) and 1.61 (1.50-1.74), respectively], unmarried (including divorced or widowed) [OR (95%CI): 1.28 (1.17-1.40)], primiparae [OR (95%CI): 1.34 (1.29-1.40)], previous cesarean section [no previous cesarean section as reference, OR (95%CI) of 1 and ≥2 times of previous cesarean section were 1.30 (1.24-1.36) and 1.85 (1.65-2.08), respectively], antenatal examination<8 [OR (95%CI): 2.72 (2.62-2.81)], multiple pregnancies [OR (95%CI): 15.00 (14.01-16.06)], placenta previa [OR (95%CI): 6.90 (6.35-7.50)], placental abruption [OR (95%CI): 8.18 (7.36-9.10)], gestational hypertension [OR (95%CI): 2.29 (2.17-2.42)], gestational diabetes mellitus [OR (95%CI): 1.43 (1.37-1.49)], anemia [OR (95%CI): 1.10 (1.07-1.14)], and heart diseases [OR (95%CI): 2.98(2.43-3.65)] were all positively correlated with preterm birth. The risk of preterm birth in pregnant women exposed to 1, 2, 3, 4, 5, 6 and ≥7 preterm birth related factors was 1.51, 2.29, 4.49, 9.69, 20.87, 46.88 and 192.11 times that of non-exposed women, respectively (all P values<0.001). Conclusion: Preterm birth is associated with maternal general characteristics, pregnancy and disease status, and the combined effect of preterm birth related factors significantly increases the risk of preterm birth.

[Success rate and influencing factors of external cephalic version for singleton pregnancies in the third trimester].

Objective: To investigate the factors associated with the success rate of external cephalic version (ECV) for singleton and non-cephalic presentation pregnancies in the third trimester. Methods: A retrospective study of ECV among singleton and non-cephalic presentation pregnant women in 36-40 weeks of gestation at Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region from January 2016 to June 2018 was analyzed. Results: (1) Totally, 251 cases of 358 pregnant women who underwent ECV were successful, with a total success rate of 70.1% (251/358). The success rate of multipara was 79.1% (129/163), while 62.6% (122/195) in primipara (P<0.01). The total vaginal delivery rate was 52.2% (187/358), the vaginal delivery rate of multipara was 61.3% (100/163), while 44.6% (87/195) in primipara (P<0.01). (2) Spontaneous reversion occurred in 7.6%(19/251) of ECV successful women, the rate of reversion of multipara was 10.9% (14/129), higher than that of the primipara [4.1% (5/122); P<0.01]. (3) Among the 232 pregnant women who did not reverted after successful ECV, 187 cases of successful vaginal delivery, the vaginal delivery rate was 80.6% (187/232); the vaginal delivery rate of the multipara was 87.0%(100/115), which was higher than that of the primipara [74.4%(87/117); P<0.01]. (4) The variables significantly associated with ECV success were parity, type of breech, whether fetal presentation was in pelvic or not (all P<0.05). The complication rate was 2.2% (8/358), among which the incidence of fetal distress, placental abruption and transient fetal heart abnormalities were 0.6% (2/358), 0.3% (1/358) and 1.4% (5/358) respectively. Conclusion: By close monitoring, ECV is a safe and effective procedure in selected appropriate cases, and worthy of clinical application.

Specific genes related to nucleopolyhedrovirus in Bombyx mori susceptible and near-isogenic resistant strains through comparative transcriptome analysis.

Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the primary pathogens that causes severe economic losses to sericulture. Comparative transcriptomics analysis has been widely applied to explore the antiviral mechanism in resistant strains. Here, to identify genes involved in BmNPV infection, we identified differentially expressed genes (DEGs) and performed weighted gene co-expression network analysis (WGCNA) between two Bombyx mori strains: strain 871 (susceptible to BmNPV infection) and the near-isogenic strain 871C (resistant to BmNPV). Our results showed that 400 genes were associated with resistance in strain 871C, and 76 genes were related to susceptibility in strain 871. In addition, the correlation analysis of DEGs and WGCNA showed that 40 genes related to resistance were highly expressed in the resistant strain. Among them, gene BGIBMGA004291 was the most noticeable. We further identified the effect of gene BGIBMGA004291, which encoded a multiprotein bridge factor 2 (MBF2) family member (MBF2-10), on viral infection in cells. Our data suggested that MBF2-10 inhibited viral infection. Taken together, this study showed specific module trait correlations related to viral infection in strains 871 and 871C, and we identified a resistance-related gene. These findings suggested promising candidate genes with antiviral activity, aiding in the analysis of the antiviral molecular mechanisms in resistant strains.

[The detection of pediatric mycoplasma pneumonia cases by polymerase chain reaction and it's clinical significance].

Mycoplasma DNA in nasopharynx secretion from seventy pediatric mycoplasma cases was detected, using rapid feit of PCR DNA sample preparation method and simple PCR processes. The result of PCR showed that: fifty-three positive cases with a positive rate 75.7%, comparing with only 53.8% positive rate using mycoplasma culture method (P < 0.05). Thirteen PCR positive patients were treated by Venoclysis Erythromycin for 10-14 days but mycoplasma DNA was identified by PCR again. Among them, eight cases turned negative, but five cases still remained positive. The resalt showed that this method was not only more sensitive and reliable than conventional culture techniques, but also could simplify the PCR processes. It could be used for routine mycoplasma pneumonia test and for early diagnosis, which leads to early treatment and evaluation of therapeufic effect.