Establishment and application of a rapid molecular diagnostic platform for the isothermal visual amplification of group B Streptococcus based on recombinase polymerase.

With growing concerns about Group B streptococcal (GBS) infections and their adverse effects on perinatal pregnancies, including infection, premature delivery, neonatal septicemia, and meningitis, it is urgent to promote GBS screening at all pregnancy stages. The purpose of this study is to establish a device-independent, fast, sensitive, and visual GBS detection method. Taking advantage of the characteristics of the recombinase polymerase isothermal amplification (RPA), the activity of the nfo nuclease cleavage base analog (tetrahydrofuran, THF) site, and the advantages of visual reading of the lateral flow chromatography strip (LFS), a GBS detection method was developed. This method focused on the conservative region of the Christie-Atkins-Munch-Petersen factor encoded by the cfb gene, a virulence gene specific to GBS. Two forward primers, two biotin-labeled reverse primers, and one fluorescein isothiocyanate (FITC)-labeled and C3spacer-blocked probe were designed. The study involved optimizing the primer pair and probe combination, determining the optimal reaction temperature and time, evaluating specificity, analyzing detection limits, and testing the method on 87 vaginal swabs from perinatal pregnant women. The results showed that the visual detection method of GBS-RPA-LFS, using the cfb-F1/R2/P1 primer probe, could detect GBS within 15 min at the temperature ranging from 39°C to 42°C. Furthermore, the method specifically amplified only GBS, without cross-reacting with pathogens like Lactobacillus iners, Lactobacillus crispatus, Candida albicans, Listeria monocytogenes, Yersinia enterocolitica, Klebsiella Pneumoniae, Enterobacter cloacae, Citrobacter freundii, Vibrio alginolyticus, Vibrio parahaemolyticus, Salmonella typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa, or Trichomonas vaginalis. It could detect a minimum of 100 copies per reaction. In clinical 98 samples of vaginal swabs from pregnant women, the agreement rate between the GBS-RPA-LFS method and TaqMan real-time fluorescence quantification method was 95.92%. In conclusion, this study successfully established a combined RPA and LFS GBS in situ detection platform, with short reaction time, high sensitivity, high specificity, portability, and device independence, providing a feasible strategy for clinical GBS screening.

Prevalence and associated factors of insomnia symptoms among pregnant women in the third trimester in a moderately developing region of China.

BACKGROUND: Insomnia is the most common sleep disorder in the general population, especially among pregnant women, and it is considered a major public health issue. Not only can it cause mental and physical problems in pregnant women, but it may also affect the growth of the fetus. However, there are few reports on the prevalence and influencing factors of insomnia symptoms in third-trimester women in China. The objective of this study was to assess the prevalence of insomnia symptoms among pregnant women in the third trimester in a moderately developing region of China and to further explore the associated factors of insomnia symptoms from various aspects. METHODS: A cross-sectional survey was conducted among eligible pregnant women in the third trimester from December 2022 to February 2023. Data on socio-demographic characteristics, clinical characteristics, and behavioral and psychological characteristics of pregnant women were collected through a structured questionnaire. The Chi-square test and multivariate logistics regression were applied to explore the associated factors of insomnia symptoms. RESULTS: A total of 535 pregnant women in the third trimester were included in this study, and the prevalence of insomnia symptoms was 59.8%. Multivariate logistic regression analysis revealed that pregnant women who lived together with elders (OR: 0.58, 95% CI: 0.40-0.86), had low perceived stress (OR: 0.58, 95% CI: 0.35-0.97), had no threatened abortion (OR: 0.55, 95% CI: 0.32-0.93) and had good doctor-patient communication (OR: 0.66, 95% CI: 0.45-0.98) were more likely to stay away from insomnia symptoms. However, pregnant women with anxiety symptoms (OR: 2.27, 95% CI: 1.28-4.03), fear of childbirth (OR: 1.63, 95% CI: 1.11-2.40) and a high experience of COVID-19 fear (OR: 1.61, 95% CI: 1.03-2.54) tended to have insomnia symptoms. CONCLUSIONS: The prevalence of insomnia symptoms in pregnant women is high in Lianyungang city in eastern China in the third trimester. Insomnia symptoms is influenced by multiple factors. There is an urgent need to develop interventions to reduce the prevalence of insomnia symptoms in the third trimester and to focus on pregnant women with risk factors for insomnia symptoms.

Establishment and application of a point-of-care testing and diagnosis method for early immediate expression gene IE1 of cytomegalovirus in maternal urine based on isothermal amplification.

BACKGROUND: Human Cytomegalovirus virus (HCMV) is a worldwide virus that causes no serious symptoms in most adults. However, HCMV infection during pregnancy, it may lead to a series of serious complications, such as hearing loss, mental retardation, visual impairment, microcephaly and developmental retardation. AIM: The aim of this study was to develop a simple, low dependence on equipment and accurate method for HCMV detection based on the recombinase polymerase amplification (RPA) and lateral flow chromatography strip (LFS) reading. METHODS: In order to meet the feasibility of HCMV early screening, three pairs of RPA primers were designed based on the UL123 gene encoding IE1, which was expressed immediately in the early stage of HCMV. In order to improve the specificity of the reaction and satisfy the visual detection, a specific probe was designed to insert THF site between upstream and downstream primers, fluorescein isothiocyanate (FITC) and C3spacer were used to modify the 5' end and the 3' end respectively, and Biotin was used to modify the 5' end of the reverse primer. HCMV standard strain AD169 was enriched by ARPE-19 cells culture, and its genome was extracted. The primers and probes were screened by RPA-LFS test, and the optimal reaction temperature and time were determined The specificity was verified in different viruses, bacteria and parasites. The standard curve was drawn based on the constructed recombinant plasmid of pMD18T-HCMV-UL123 and used for HCMV genomic DNA quantification and determination of the detection sensitivity. Urine samples from artificial HCMV contamination or clinical collection were prepared to evaluate the consistency with the results of real-time quantitative PCR. RESULTS: The results showed that the primers and probes for HCMV RPA-LFS detection based on UL123 gene were successfully screened, the amplification of HCMV genomic DNA with as low as 30 copies could be completed at 37 °C within 15 min, it did not react with Human herpesvirus 1, Streptococcus pyogenes, Candida albicans, Listeria monocytogenes, Y. enterocolitica, Klebsiella Pneumoniae, Enterobacter cloacae, Citrobacter freundii, Vibrio alginnolyfificus, Vibrio parahaemolyticus, S. typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa and Trichomonas vaginalis. The positive rate of PCR was 96.67 % in 30 simulated urine samples and 100 % in 127 clinical urine samples with the same UL123 gene detection. CONCLUSIONS: To sum up, we developed a diagnostic method for HCMV based on UL123 gene combined with RPA and LFS, which is low dependent on equipment, fast, sensitive and specific, provide reference for point-of-care testing HCMV in grass-roots laboratories and remote areas.

Fear of childbirth and its determinants in pregnant women in the third trimester: a cross-sectional study.

BACKGROUND: Fear of childbirth (FOC) is a prevalent issue among pregnant women and significantly relates to adverse outcomes for the mother and child. However, it is not clear the prevalence and risk factors of FOC among pregnant women in a region with a moderate level of economic development in China. The aim of this study was to investigate the prevalence and risk factors of FOC among pregnant women in the third trimester of pregnancy in Lianyungang city, Eastern China. METHODS: A cross-sectional survey was conducted from December 2022 to February 2023 among pregnant women in the third trimester who met the inclusion criteria and visited Lianyungang Maternal and Child Health Hospital in Jiangsu Province, Eastern China. A structured questionnaire including sociodemographic characteristics, clinical characteristics, FOC, family function, doctor-patient communication, social support, general self-efficacy, anxiety, depression, insomnia symptoms, and quality of life was used to collect data. A multiple linear regression model was used to identify predictors of FOC. RESULTS: This study included 535 pregnant women in the third trimester. The mean score of FOC was 30.67 ± 10.18, and the median score was 29.00. The prevalence of FOC was 56.64%. Multiple linear regression analysis revealed that pregnant women with electronic screen exposure time more than 5 h per day (ß = 2.02, 95%CI: 0.50-3.53, P < 0.05), no history of cesarean section (ß = 2.66, 95%CI: 0.61-4.71, P < 0.05), likes sour food or hates greasy food (ß = 1.75, 95%CI: 0.00-3.50, P < 0.05), anxiety (ß = 0.50, 95%CI: 0.21-0.80, P < 0.05) and depression (ß = 0.30, 95%CI: 0.04-0.57, P < 0.05) were more likely to have a greater level of FOC than their counterparts. However, a significantly lower level of FOC was observed in pregnant women who were multipara (ß=-1.64, 95%CI: -3.27-0.01, P < 0.05), not worrying about delivery without family members (ß=-3.75, 95%CI: -5.26-2.25, P < 0.001), had good family function (ß=-0.32, 95%CI: -0.64-0.00, P < 0.05) and doctor-patient communication (ß=-0.33, 95%CI: -0.64-0.02, P < 0.05). CONCLUSIONS: The prevalence of FOC was high in Lianyungang city, Eastern China. FOC is influenced by multiple factors. There is an urgent need to develop interventions to reduce the prevalence of FOC in the third trimester of pregnancy, and to pay attention to pregnant women with risk factors for FOC.

Effect of biological, psychological, and social factors on maternal depressive symptoms in late pregnancy: a cross-sectional study.

Introduction: Depression commonly occurs during pregnancy and has become a major public health concern. Depression not only affects the individual but also causes adverse consequences for families and children. However, little is known regarding the depression status and its influencing factors in women during late pregnancy in China. This study aimed to assess the prevalence of maternal depressive symptoms in late pregnancy during the coronavirus disease 2019 (COVID-19) pandemic and further explore the effect of biological, psychological, and social factors on depressive symptoms. Methods: An institution-based cross-sectional survey was conducted among eligible women in the late pregnancy stage and underwent prenatal examination at Lianyungang Maternal and Child Health Hospital in Jiangsu Province, Eastern China from December 2022 to February 2023. Data regarding depressive symptoms and biological, psychological, and social factors of the pregnant women were collected via a structured questionnaire. Chi-square test, Fisher's exact tests, and binary logistics regression were used to analyze the data. Results: In total, 535 women in the late pregnancy stage were included in this study, 75 (14.0%) of whom exhibited depressive symptoms. A binary logistic regression analysis revealed that pregnant women who were multiparous (OR: 2.420, 95% CI: 1.188-4.932) and had moderate or severe insomnia symptoms (OR: 4.641, 95% CI: 1.787-12.057), anxiety (OR: 8.879, 95% CI: 4.387-17.971), high fear of COVID-19 (OR: 2.555, 95% CI: 1.255-5.199), moderate or severe family dysfunction (OR: 2.256, 95% CI: 1.141-4.461), and poor social support (OR: 2.580, 95% CI: 1.050-6.337) tended to show depressive symptoms. Conversely, pregnant women who received regular prenatal care (OR: 0.481, 95% CI: 0.243-0.951) and had good drinking water quality at home (OR: 0.493, 95% CI: 0.247-0.984) were more likely to avoid developing depressive symptoms. Conclusion: This study found that the prevalence of maternal depressive symptoms during late pregnancy was high and had multiple influencing factors. Thus, screening for depressive symptoms in women in the late pregnancy stage and providing special intervention programs are necessary, especially for those with risk factors.