The Role of Placental DNA Methylation at Reproduction-Related Genes in Associations between Prenatal Bisphenol Analogues Exposure and the Digit Ratio in Children at Age 4: A Birth Cohort Study.

Placental DNA methylation (DNAm) may be a potential mechanism underlying the effects of prenatal bisphenol analogues (BPs) exposure on reproductive health. Based on the Shanghai-Minhang Birth Cohort Study (S-MBCS), this study investigated associations of placental DNAm at reproduction-related genes with prenatal BPs exposure and children's digit ratios at age 4 using multiple linear regression models, and mediation analysis was further used to examine the mediating role of placental DNAm in the associations between prenatal BPs exposure and digit ratios among 345 mother-child pairs. Prenatal exposure to bisphenol A (BPA) was associated with hypermethylation at Protocadherin 8 (PCDH8), RBMX Like 2 (RBMXL2), and Sperm Acrosome Associated 1 (SPACA1), while bisphenol F (BPF) exposure was associated with higher methylation levels of Fibroblast Growth Factor 13 (FGF13). Consistent patterns were found in associations between higher DNAm at the 4 genes and increased digit ratios. Further mediation analysis showed that about 15% of the effect of BPF exposure on increased digit ratios was mediated by placental FGF13 methylation. In conclusion, the altered placental DNAm status might be a mediator underlying the feminizing effect of prenatal BPs exposure.

Prenatal exposure to Per- and polyfluoroalkyl substances and adiposity measures of children at 4 and 6 years: A prospective birth cohort in China.

There is growing evidence that prenatal exposure to Per- and polyfluoroalkyl substances (PFAS) was associated with childhood obesity, but evidence on multiple adiposity measures including arm circumference (AC), and waist circumference (WC) among Chinese children is limited. We investigated the associations of prenatal exposure to PFAS with adiposity measures of children at 4 and 6 years of age in the Shanghai-Minhang Birth Cohort Study. A total of 573 mother-child pairs with maternal PFAS concentrations and at least one measurement of adiposity measures of children were included in the present study. Eleven PFAS were assessed in maternal fasting blood samples. Information on children's weight, height, AC, and WC was collected at follow-ups. Weight for age Z score (WAZ), body mass index for age Z score (BMIz), and children overweight were calculated based on the World Health Organization Child Growth Standards. Multivariate linear regression, Poisson regression with robust error variance, and Bayesian Kernel Machine Regression (BKMR) models were used to examine the associations of prenatal exposure to PFAS with children's adiposity measures. Eight PFAS with detection rates above 85 % were included in the analyses. In the multivariate linear regression models, maternal PFNA concentrations were associated with a greater AC (ß = 0.29, 95 % Confidence Interval (CI): 0.04-0.55) in 4-year-old children and with an increase in WAZ (ß = 0.26, 95 % CI: 0.06-0.46), BMIz (ß = 0.31, 95 % CI: 0.09-0.53), AC (ß = 0.49, 95 % CI: 0.08-0.90), and WC (ß = 1.47, 95 % CI: 0.41-2.52) in 6-year-old children. We also observed the associations of maternal concentrations of PFOS, PFNA, PFUdA, and PFTrDA with the increased risk of children overweight in 6-year-old children. BKMR models further supported the findings from multivariate linear regression and Poisson regression models, and identified PFNA as the most important contributor. Moreover, the associations described above were generally more pronounced in girls. In conclusion, prenatal exposure to PFAS was associated with an increased risk of children's adiposity with a sex-specific manner, and PFNA contributed most to the associations after controlling for the effect of co-exposure to other PFAS compounds, especially among girls at 6 years of age.

Bile acid metabolites in early pregnancy and risk of gestational diabetes mellitus: Results from a prospective cohort study.

AIMS: To evaluate the associations of plasma bile acid metabolites, especially in early pregnancy, with gestational diabetes mellitus (GDM) risk among pregnant women. MATERIALS AND METHODS: Plasma concentrations of 15 bile acid metabolites were measured in 645 women at early pregnancy from the Jiashan Birth Cohort using a liquid chromatography-tandem mass spectrometry metabolomics platform. Using logistic and cubic spline models, we examined associations between baseline plasma bile acid metabolites and GDM risk during mid-late pregnancy. A meta-analysis of prospective studies of bile acid and GDM risk was performed. RESULTS: The linear and nonlinear univariate models identified eight metabolites associated with GDM, including cholic acid, taurocholic acid (TCA), glycocholic acid, glycochenodeoxycholic acid, deoxycholic acid, lithocholic acid (LCA), ursodeoxycholic acid and taurolithocholic acid (all P <0.05). Multivariable analysis indicated that TCA and LCA levels were positively (odds ratio [OR] 2.07, 95% confidential interval [CI] 1.05, 3.96; P = 0.030) and negatively (OR 0.83, 95% CI 0.68, 1.01; P = 0.065) associated with GDM, respectively, after adjusting for confounders. The TCA-GDM association showed a positive linear shaped relationship (OR 2.07, 95% CI 1.05, 3.96; P = 0.030); while LCA was negatively related with GDM risk in linearity (OR 0.83, 95% CI 0.68, 1.01; P = 0.065). The meta-analysis of five studies showed a consistent bile acid and GDM association, with a risk ratio (RR) of 2.43 (1.95, 3.03). CONCLUSIONS: This study indicated that, the levels of circulating bile acids in early pregnancy were associated with risk of GDM, independent of GDM risk factors. Most GDM-associated bile acids were primary conjugated and secondary unconjugated bile acids.

Maternal per- and poly-fluoroalkyl substances exposure and child adiposity measures: A birth cohort study.

Maternal exposure to per- and polyfluoroalkyl substances (PFAS) during pregnancy may have a programming effect on the physical development of the offspring. However, the findings of the association between PFAS and the physical development of offspring were inconsistent, and the overall effects of the PFAS mixture were unclear. In this study, we examined the associations between maternal PFAS exposure and offspring adiposity during the first two years of life. A total of 937 mother-child pairs from the Jiashan Birth Cohort Study were investigated. Thirteen PFASs were analyzed in maternal blood samples. Child weight and length were measured at birth, 1, 3, 6, 8, 12, and 24 months, and the ponderal index (PI) and weight-for-age z-scores (WAZ) were calculated. Longitudinal associations of PFAS concentrations (by quartile) with repeated data of PI and WAZ were examined using linear mixed model, and the overall effect of the PFAS mixture on adiposity measures was evaluated using quantile g-computation (QGC). Maternal PFAS exposure was associated with increased PI in both the linear mixed model and the QGC model. Among the PFAS examined, the associations between maternal PFTrDA exposure and PI were the strongest. Maternal PFAS and WAZ showed similar patterns of association. In the longitudinal cohort study, we found that adiposity in young children is increased by maternal PFAS exposure. The associations between maternal PFASs concentrations and child adiposity may be chemical-specific.

Associations of perfluoroalkyl and polyfluoroalkyl substances with gestational hypertension and blood pressure during pregnancy: A cohort study.

Previous studies have reported inconsistent associations between perfluoroalkyl and polyfluoroalkyl substances (PFAS) and gestational hypertension (GH) and blood pressure (BP) during pregnancy. Herein, we aimed to evaluate individual and overall effects of PFAS on GH and longitudinal BP measures during pregnancy. We included 826 pregnant women from the Jiashan Birth Cohort established between 2016 and 2018. Concentrations of thirteen PFAS were quantified using plasma samples collected within 16 weeks of gestation. Longitudinal BP measures were obtained from medical records, and more than nine measurements were available for 85.60% of participants. GH was defined as new-onset hypertension occurring after 20 weeks of gestation. Logistic regression models were used to examine the effect of PFAS on GH, while generalized estimating equation models evaluated the average effect of PFAS on BP in each trimester. The potential effect modification by fetal sex was also examined. Bayesian kernel machine regression (BKMR) and quantile g-computation (QgC) were implemented to explore the overall effect of the PFAS mixture. PFOA, PFOS, and PFHxS presented the highest median concentrations of 11.99, 8.81 and 5.43 ng/mL, respectively. Overall, 5.57% of subjects developed GH. PFOS, PFDA, PFUdA, and PFDoA were significantly associated with lower GH odds, and odds ratios ranged between 0.62 and 0.68. We noted associations between PFAS and lower systolic BP and diastolic BP in the third trimester, with PFDA and PFUdA exhibiting the effect on systolic BP only in pregnant women carrying a female fetus. These associations were further confirmed by BKMR and QgC, showing an inverse overall effect of the PFAS mixture. Higher concentrations of PFAS during early pregnancy were associated with lower GH risk and longitudinal BP measures in the third trimester in a population with relatively high exposure levels. Fetal sex might modify the effects of PFDA and PFUdA on systolic BP in the third trimester.

Association of pre-pregnancy body mass index and gestational weight gain with neonatal anogenital distance in a Chinese birth cohort.

BACKGROUND: This study aimed to investigate the associations of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) with anogenital distance (AGD) among newborns. METHODS: The study included 556 mother-newborn pairs from the Jiashan birth cohort. AGD was measured as AGDAP (from the center of the anus to the anterior base of the penis, where the penile tissue meets the pubic bone) and AGDAS (from the center of the anus to the posterior base of the scrotum, where the skin changes from rugate to smooth) in males and AGDAC (from the center of the anus to the clitoris) and AGDAF (from the center of the anus to the posterior convergence of the fourchette) in females. Multiple linear regression models were used to estimate the associations of pre-pregnancy BMI and GWG, with AGD. RESULTS: After adjusting for pre-pregnancy BMI and other potential confounders, male newborns whose mothers had excessive GWG had shorter AGDAP than those whose mothers had normal GWG. Male newborns whose mothers had normal pre-pregnancy BMI and inadequate/excessive GWG had shorter AGDAP than the reference group where mothers had normal pre-pregnancy BMI and GWG in stratified analyses. CONCLUSION: Gestational weight gain during pregnancy was associated with AGD in newborns in this birth cohort.

In China, the prevalence of underweight and overweight/obesity remained high among women. Appropriate pre-pregnancy body mass index (BMI) and gestation weight gain (GWG) were critical to reduce the risk of adverse birth outcomes. The anogenital distance (AGD) was measured as an indicator of neonatal reproductive function and was associated with adverse reproductive outcomes in adults. Thus, we investigated the associations of both sub-optimal pre-pregnancy BMI, as well as GWG, with AGD among newborns to draw a picture about their effect on offspring reproductive health.A total of 556 mother-newborns were included in the study from the Jiashan birth cohort in China. We extracted information about maternal lifestyles, social demographic characteristics, diet, and medical history from questionnaires conducted during 8­16 gestational weeks and medical records. AGD among newborns was measured within 3 days of delivery.We found that maternal excessive GWG was associated with shorter AGD in male newborns after adjusting for maternal pre-pregnancy BMI in multiple linear regression models. The study also suggested that maternal inadequate GWG was associated with a shorter AGD in male newborns, which needed to be corroborated in further studies with a larger sample size.In conclusion, health professionals shall implement sufficient intervention to prevent suboptimal GWG during prenatal checkups.

Differential methylation of genes in the human placenta associated with bisphenol A exposure.

Prenatal exposure to bisphenol A (BPA) is associated with numerous adverse health outcomes among offspring. Although DNA methylation is considered one of the underlying causes of these associations, few studies have focused on the association between prenatal BPA exposure and DNA methylation in the human placenta. In this study, we examined the association between prenatal BPA exposure and DNA methylation in the placenta of 146 mother-infant pairs from the Shanghai-Minhang Birth Cohort Study. BPA concentrations in maternal urine samples were measured using high-performance liquid chromatography. Six placenta samples were selected for whole-genome methylation analysis using Infinium Human Methylation 450K Beadchip, followed by pyrosequencing-based methylation analysis of three selected genes in 146 placentas. Among 282 differentially methylated CpGs, representing 208 genes, 127 were hypermethylated, and 155 were hypomethylated in the BPA exposure group. Prenatal BPA exposure was associated with a higher methylation level of HLA-DRB6 in individuals as determined using pyrosequencing, which was consistent with the whole-genome methylation analysis results. Compared with that subjects with low BPA exposure, the methylation level (ln-transformed) of HLA-DRB6 in placentas from those with high BPA exposure increased by 0.29% (95% confidence interval[CI]: 0.02%, 0.56%) at the CpG2 site, and the average methylation level (ln-transformed) of the three CpG sites increased by 0.30% (95%CI: -0.03%, 0.63%). Our findings provide evidence that prenatal BPA exposure might alter DNA methylation levels in the placenta.

Association between prenatal bisphenol a exposure and promoter hypermethylation of CAPS2, TNFRSF25, and HKR1 genes in cord blood.

In utero exposure to bisphenol A (BPA) in early stages of development has been reported to exert adverse health effects on offspring later in life. Epigenetic alterations, particularly DNA methylation, may be one plausible biological mechanism involved. We examined the association between maternal BPA exposure and DNA methylation in cord blood. We randomly selected 96 paired samples of maternal urine and infant cord blood collected from the Shanghai-Minhang Birth Cohort. BPA levels in maternal urine were measured using high-performance liquid chromatography (HPLC). Three cord blood samples with maternal BPA levels >2.0 µg/g Cr and three samples with undetected BPA were randomly selected for genome-wide methylation analysis using methylated DNA binding domain sequencing (MBD-Seq). The genes with hypermethylated promoter regions were chosen for validation using quantitative methylation-specific polymerase chain reaction (Q-MSP). Based on MBD-seq results, we observed that maternal BPA exposure was primarily associated with hypermethylation of genes involved in signal transduction in the nervous system. Using Q-MSP, we further validated the association between maternal BPA exposure and promoter hypermethylation of three genes in multiple linear regression models: a log unit increase in BPA was associated with 12.63% (95%CI: 7.99, 17.26), 11.17%, (95%CI: 3.31, 19.02), and 16.57% (95% CI: 10.59, 22.56) increase in promoter of CAPS2, TNFRSF25, and HKR1 methylation, respectively. Our findings provide evidence that in utero exposure to BPA could alter the offspring's epigenome by altering DNA methylation pattern.

Concentrations of perfluoroalkyl and polyfluoroalkyl substances and blood glucose in pregnant women.

BACKGROUND: Evidence on the association between exposure to perfluoroalkyl and polyfluoroalkyl substances (PFASs) and blood glucose concentrations in pregnant women is inconsistent. This study aimed to examine the association between PFAS exposure and the concentrations of fasting plasma glucose (FPG) and one-hour plasma glucose (1 h-PG) after a 50-g oral glucose tolerance test in pregnant women. METHODS: The study was based on the Shanghai-Minhang Birth Cohort, in which 1292 pregnant women were recruited. Among them, 981 women provided blood samples (at 12-16 gestational weeks) for PFAS measurement. FPG data collected from 856 women at 12-20 GW and 1 h-PG data collected from 705 women at 20-28 GW were obtained through medical records from the routine prenatal care system. High FPG or 1 h-PG was defined as ≥90th percentile of FPG or 1 h-PG. The analysis of eight PFASs was conducted in this study: perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUdA), perfluorododecanoic acid (PFDoA), and perfluorotridecanoic acid (PFTrDA). The odds ratios (ORs) and associated 95% confidence intervals (CIs) were estimated to determine the associations of each PFAS compound with high FPG and 1 h-PG from a logistic regression model. RESULTS: After adjustment for potential confounders, most PFASs were positively associated with high 1 h-PG concentrations. The OR for high 1 h-PG concentrations was 1.87 (95% CI: 1.15-3.05) with a one log unit increase of PFOS; similar associations were observed for PFNA (OR: 2.15, 95% CI: 1.24-3.74), PFDA (OR: 1.61, 95% CI: 1.10-2.44), PFUdA (OR: 1.71, 95% CI: 1.12-2.62), and PFDoA (OR: 1.34, 95% CI: 1.00-1.81). When the PFAS concentrations were categorized into three groups by tertiles, the highest tertiles of PFOS, PFOA, PFNA, PFDA, PFDoA, and PFTrDA had a statistically significant increase in the risk of high 1 h-PG concentrations compared with the lowest tertiles. No statistically significant association was observed between PFAS exposure and high FPG. CONCLUSION: PFAS exposure was associated with an increased risk of high 1 h-PG among pregnant women, but no such association was observed for FPG.

Preconceptional paternal antiepileptic drugs use and risk of congenital anomalies in offspring: a nationwide cohort study.

Recent studies have shown that certain pharmacological agents used by fathers before conception may increase the risk of adverse neonatal outcomes in offspring. However, little is known about the effect of paternal use of antiepileptic drugs (AEDs) on congenital anomalies in children. Based on Danish national registers, we conducted a cohort study of 733, 282 singletons born from 1997 to 2008, with follow-up throughout 2013. The children whose fathers used AEDs during the 3 months before conception were categorized as the exposed. Logistic regression model was used to examine association between paternal AEDs use before conception and the risk of congenital anomalies in offspring. Compared with unexposed children, the exposed had a 23% increased risk of congenital anomalies (odds ratios (OR) 1.23, 95% confidence interval [CI] 1.10-1.37) after adjusting for potential confounders. When extending the exposure window to 1 year before conception to the end of pregnancy, except for those using AEDs during 3 months before conception (the susceptible period of exposure), the increased risks were also observed in children whose fathers were former users (i.e., those using AEDs only from 1 year to 3 months before conception) (OR 1.29, 95%CI 1.03-1.61) and later users (i.e., those using AEDs only during pregnancy) (OR 1.35, 95%CI 1.12-1.65). This study suggested that the mildly increased risk of congenital anomalies in the offspring associated with paternal AEDs use before conception may be attributable to the underlying indications related to AEDs use.

Prenatal plasma concentrations of Perfluoroalkyl and polyfluoroalkyl substances and neuropsychological development in children at four years of age.

OBJECTIVE: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent pollutants and have endocrine disruptive and neurotoxic effects. The association between maternal PFAS concentrations and neuropsychological development in children is inconclusive. The present study aimed to examine the effect of maternal PFAS concentrations on neuropsychological development in 4-years-old children. METHODS: We used data from Shanghai-Minhang Birth Cohort, which recruited pregnant women at 12-16 gestational weeks. Among 981 women having PFAS measurement, 533 mother-child pairs were included in the study. A total of eight PFASs were measured, including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUdA), perfluorododecanoic acid (PFDoA), and perfluorotridecanoic acid (PFTrDA). When infants turned 4 years old, mothers were asked to complete the Ages and Stages Questionnaires® (ASQ) to assess neuropsychological development of their children. Poisson regression model with robust variance estimates was used to examine the association between maternal PFAS concentrations and each developmental subscale of the ASQ. RESULTS: Prenatal plasma concentrations of most PFASs tended to be associated with increased risk of development problem in personal-social skills, including PFHxS, PFOS, PFOA, PFNA, PFDA, and PDUdA, and the associations for PFNA and PFDA were significant (per natural log unit increase: RRPFNA = 1.92, 95% CI: 1.21, 3.05; RR PFDA = 1.66, 95% CI: 1.17, 2.37). In stratified analyses by child' sex, the consistent pattern of higher risk of developmental problems in personal-social skills associated with most PFASs was mainly observed among girls (RRPFOS = 2.56, 95% CI: 1.20, 5.45; RRPFOA = 9.00, 95% CI: 3.82, 21.21; RRPFNA = 3.11, 95% CI: 1.36, 7.13; RRPFDA = 2.20, 95% CI: 1.21, 4.00; RRPFUdA = 2.44, 95% CI: 1.14, 5.20; RRPFDoA = 1.62, 95% CI: 1.04, 2.54). Boys with higher maternal PFOA concentrations had a decreased risk of developmental problems in gross motor skills (RR = 0.47, 95% CI: 0.25, 0.89). CONCLUSION: Prenatal plasma PFAS concentrations were associated with neuropsychological development in girls at 4 years of age, mainly in the subset of personal-social skills.

Association between maternal HIV infection and low birth weight and prematurity: a meta-analysis of cohort studies.

BACKGROUND: To assess the association between maternal human immunodeficiency virus (HIV) infection and low birth weight (LBW)/prematurity (PTD), we conducted a meta-analysis of cohort studies of HIV infected and uninfected women. METHODS: Several English and Chinese databases were searched (updated to May 2015) to find the studies reporting infant outcomes associated with exposure to maternal HIV infection during pregnancy. Relevant articles were manually selected based on several inclusion and exclusion criteria. RESULTS: Fifty-two cohort studies including 15,538 (for LBW) and 200,896 (for PTD) HIV infected women met the inclusion criteria. There was significant heterogeneity among studies for maternal HIV infection associated with LBW/PTD (I(2) = 71.7%, P < 0.05, and I(2) = 51.8%, P < 0.05 for LBW and PTD, respectively). The meta-analysis demonstrated that the maternal HIV infection was significantly associated with both LBW (pooled odds ratio (OR): 1.73, 95% confidence interval (CI): 1.64, 1.82, P < 0.001) and PTD (pooled OR: 1.56, 95% CI: 1.49, 1.63, P < 0.001). No significant difference in the relationship between maternal HIV infection and adverse pregnancy outcomes was detected among the groups of different study periods. HIV infected women were at slightly higher risk of LBW in developing countries compared with women in developed countries (OR: 2.12 (95% CI: 1.81, 2.48) vs. 1.75 (95% CI: 1.44, 2.12)). Antiretroviral drugs usage did not significantly change the associations of maternal HIV exposure with LBW and PTD. CONCLUSIONS: HIV infected women were at higher risk of having a low birth weight infant or a preterm delivery infant compared with uninfected women. Such associations did not change significantly over time or were not significantly affected by the usage of antiretroviral drugs.

The geographic distribution patterns of HIV-, HCV- and co-infections among drug users in a national methadone maintenance treatment program in Southwest China.

BACKGROUND: HIV-, HCV- and HIV/HCV co-infections among drug users have become a rapidly emerging global public health problem. In order to constrain the dual epidemics of HIV/AIDS and drug use, China has adopted a methadone maintenance treatment program (MMTP) since 2004. Studies of the geographic heterogeneity of HIV and HCV infections at a local scale are sparse, which has critical implications for future MMTP implementation and health policies covering both HIV and HCV prevention among drug users in China. This study aimed to characterize geographic patterns of HIV and HCV prevalence at the township level among drug users in a Yi Autonomous Prefecture, Southwest of China. METHODS: Data on demographic and clinical characteristics of all clients in the 11 MMTP clinics of the Yi Autonomous Prefecture from March 2004 to December 2012 were collected. A GIS-based geographic analysis involving geographic autocorrelation analysis and geographic scan statistics were employed to identify the geographic distribution pattern of HIV-, HCV- and co-infections among drug users. RESULTS: A total of 6690 MMTP clients was analyzed. The prevalence of HIV-, HCV- and co-infections were 25.2%, 30.8%, and 10.9% respectively. There were significant global and local geographic autocorrelations for HIV-, HCV-, and co-infection. The Moran's I was 0.3015, 0.3449, and 0.3155, respectively (P < 0.0001). Both the geographic autocorrelation analysis and the geographic scan statistical analysis showed that HIV-, HCV-, and co-infections in the prefecture exhibited significant geographic clustering at the township level. The geographic distribution pattern of each infection group was different. CONCLUSION: HIV-, HCV-, and co-infections among drug users in the Yi Autonomous Prefecture all exhibited substantial geographic heterogeneity at the township level. The geographic distribution patterns of the three groups were different. These findings imply that it may be necessary to inform or invent site-specific intervention strategies to better devote currently limited resource to combat these two viruses.

[Hemocyte morphology and classification in Oncomelania hupensis].

Hemocytes were collected from Oncomelania hupensis in Junshan, Hunan Province and Puge, Sichuan Province, respectively, and stained with Giemsa solution for light microscopic examination. The cells were classified morphologically. Five types of hemocytes were identified, viz., large acidophilic hyalinocytes, small acidophilic hyalinocytes, basophilic hyalinocytes, basophilic small granulocytes and basophilic large granulocytes. The proportion of small acidophilic hyalinocytes was the most abundant hemocyte [36.7% (229/624) in snails from Junshan and 31.7% (257/810) in snails from Puge], followed by basophilic hyalinocyte [23.1% (144/624) in Junshan and 24.4% (198/810) in Puge]. Basophilic large granulocyte was about 9.3% (58/624) in Junshan and 11.6% (94/810) in Puge. The length of large acidophilic hyalinocytes was the maximum and its nucleocytoplasmic ratio was minimum, followed by small acidophilic hyalinocytes. The length of basophilic cells was shorter and its nucleocytoplasmic ratio was smaller than those of acidophilic cells. There was no significant difference in cellular constituents of hemocytes and the morphological features of hyalinocytes between the snails from Junshan and Puge, while the length and nucleocytoplasmic ratio of granulocytes in Junshan snails were smaller than those of Puge ones.

Gestational organophosphate esters (OPEs) exposure in association with placental DNA methylation levels of peroxisome proliferator-activated receptors (PPARs) signaling pathway-related genes.

BACKGROUND: Organophosphate esters (OPEs) exposure could affect offspring health. However, the underlying mechanisms are not well documented. OBJECTIVES: Based on a birth cohort study, we aimed to investigate the associations among gestational OPEs exposure, placental DNA methylation levels of peroxisome proliferator-activated receptor (PPAR) signaling pathway-related genes, and fetal growth. METHODS: We measured the concentrations of eight OPE metabolites in maternal urine samples and neonatal anthropometric measurements in 733 mother-child pairs. In 327 placental samples, we assessed the DNA methylation levels of 14 genes which were involved in the PPARs signaling pathway and expressed in placenta. Multiple linear regression models were used to examine the associations of OPEs exposure with placental DNA methylation, and of OPEs and placental DNA methylation with neonatal anthropometric measurements. Causal mediation analyses were conducted to examine the potential mediating role of placental DNA methylation in the pathway between OPEs exposure and fetal growth. RESULTS: We observed a general pattern of OPEs exposure being associated with hypermethylation of candidate genes, with statistically significant associations identified for several OPEs with RXRA, ACAA1, ACADL, ACADM, PLTP, and NR1H3 methylation. Further, gestational exposure to BCIPP, DPP, BBOEP, ∑NCl-OPEs, and ∑OPEs tended to be associated with lower anthropometric measurements, with more significant associations observed on arm circumference, and abdominal and back skinfold thickness. Notably, RXRA, ACAA1, ACOX1, CPT2, ACADM, and NR1H3 methylation tended to be associated with lower neonatal anthropometric measurements, especially for abdominal and back skinfold thickness. Moreover, mediation analyses showed that 19.42 % of the total effect of DPP on the back skinfold thickness was mediated by changes in RXRA methylation, and there was a significant indirect effect of RXRA methylation. CONCLUSIONS: Gestational OPEs exposure could disrupt the placental DNA methylation levels of PPAR signaling pathway-related genes, which might contribute to the effect of OPEs on fetal growth.

Associations of prenatal exposure to bisphenols with infant anthropometry: A prospective cohort study.

BACKGROUND: Bisphenols (BPs) have been shown to exhibit developmental toxicities. Epidemiological evidence on prenatal BPs exposure and infant growth primarily confined scopes to specific BPs and birth outcomes, with few studies focusing on infant growth and reporting inconsistent findings. The joint effect of prenatal exposure to BPs mixture on infant growth was rarely studied. OBJECTIVE: This study examined associations of prenatal exposure to individual bisphenol A (BPA) and its analogues (bisphenol F [BPF], bisphenol S [BPS], bisphenol AF [BPAF], and tetrachlorobisphenol A [TCBPA]) and their mixture with infant growth. METHODS: Urinary concentrations of BPs in pregnant women were quantified. Weight, body mass index, skinfold thickness, and circumference measurements of infants were collected at birth, 6 and 12 months of age, rapid growth and overweight were further defined. Multiple linear regression models and Bayesian kernel machine regression models (BKMR) were used to analyze associations of exposure to individual BPs and BPs mixture with infants' anthropometric measurements, and to identify the important components among mixture. The risks for rapid growth and overweight of each BP were determined using modified Poisson regression models. RESULTS: A general profile of higher prenatal BPs exposure (mainly BPA, BPF, and BPS) associated with higher anthropometric measurements and higher risks of overweight during infancy was found. We also observed higher risks of rapid growth in infants following prenatal BPs exposure, with risk ratios ranging from 1.46 to 1.91. The joint effect of BPs mixture and single effect of each BP from the BKMR models were consistent with findings from the linear regression models, further suggesting that associations in girls were generally driven by BPA, BPF, or BPS, while in boys mainly by BPF. CONCLUSION: Prenatal exposure to BPs and their mixture could increase anthropometric measurements of offspring during infancy, with implications of altered growth trajectory in future.

Prenatal exposure to per- and polyfluoroalkyl substances and DNA methylation in the placenta: A prospective cohort study.

Epidemiological studies regarding the relationship between per- and polyfluoroalkyl substances (PFAS) and DNA methylation were limited. We investigated the associations of maternal PFAS concentrations with placental DNA methylation and examined the mediating role of methylation changes between PFAS and infant development. We measured the concentrations of 11 PFAS in maternal plasma during early pregnancy and infant development at six months of age. We analyzed genome-wide DNA methylation in 16 placental samples using reduced representation bisulfite sequencing. Additionally, we measured DNA methylation levels using bisulfite amplicon sequencing in 345 mother-infant pairs for five candidate genes, including carbohydrate sulfotransferase 7 (CHST7), fibroblast growth factor 13 (FGF13), insulin receptor substrate 4 (IRS4), paired like homeobox 2Ap (PHOX2A), and plexin domain containing 1 (PLXDC1). We found that placental DNA methylation profiles related to PFOA mainly enriched in angiogenesis and neuronal signaling pathways. PFOA was associated with hypomethylation of IRS4 and PLXDC1, and PFNA was associated with PLXDC1 hypomethylation. There were positive associations of CHST7 methylation with PFTrDA and IRS4 methylation with PFDoA and PFTrDA. PLXDC1 hypomethylation mediated the association between PFOA and suspected developmental delay in infants. Future studies with larger sample sizes are warranted to confirm these findings.

Preconceptional paternal alcohol consumption and the risk of child behavioral problems: a prospective cohort study.

Animal studies demonstrated that paternal alcohol exposure before conception increases the risk of adverse neurodevelopment in offspring, but limited evidence is known in humans. Based on Shanghai-Minhang Birth Cohort Study, we aimed to examine associations between preconceptional paternal alcohol consumption and child behavioral problems. Paternal alcohol consumption during the last 3 months before conception was obtained by maternal report. Children born to fathers who drank alcohol at least once a week were classified as exposed. Child behavioral problems were assessed using the Child Behavior Checklist (CBCL) at age of 2, 4, and 6. Negative binomial regression was used to estimate the rate ratio (RR) of CBCL raw scores in 796 offspring. The risks of rating scores on anxious/depressed were increased by 33% (RR 1.33, 95% CI 1.09, 1.61) and 37% (RR 1.37, 95% CI 1.02, 1.84) among boys in the exposed group at age of 4 and 6, respectively. We also found that risks of somatic complaints were increased by 18% (RR 1.18, 95%CI 1.00, 1.40) and 65% (RR 1.65, 95%CI 1.14, 2.38) among girls in the exposed group at age of 4 and 6. The increased risks of sleep problems (RR 1.25, 95% CI 1.00, 1.55) in girls at age 4, thought problems (RR 1.32, 95% CI 1.01, 1.73) in girls at age 6, rule-breaking behaviors (RR 1.35, 95% CI 1.09, 1.67) in boys at age 6 were also found. The risks of CBCL scores on anxious/depressed and sleep problems in girls at age 4, as well as the risks of somatic complaints and rule-breaking behaviors in boys at age 6 increased with the level of exposure to paternal alcohol consumption. Our findings provided preliminary evidence that preconceptional paternal alcohol consumption may increase risks of child behavioral problems.

[Heat impact upon the infectivity of hepatitis B virus in serum].

OBJECTIVE: This article was to explore the impact of temperature on hepatitis B virus infectivity. METHODS: HBV positive serum with a HBV DNA titer of 1.33 × 10(8) copies/ml was aliquots into 23 Ep tubes with 1.5 ml, 100 µl in one tube.15 tubes were incubated at 37, 56 and 65°C for 0, 30, 60, 120 and 600 minutes, respectively. The other 8 tubes were incubated at 98°C for 0, 5, 10 and 30 minutes, respectively. Post-treated serum at all time points were selected to infect HepG-2 cell. When 18 hours after infection, these cells were extensively washed with phosphate buffered saline. Cells were harvested after the addition of fresh culture medium to culture cells for 48 hours. HBV DNA was detected by FQ-PCR. RESULTS: HBV DNA was detected in cells that were infected by serum at 37°C and 56°C for 30, 60, 120 and 600 minutes, respectively. The titers for the cells incubated at 37°C were (4.85 ± 1.71) × 10(5), (3.85 ± 1.76) × 10(5), (1.67 ± 0.67) × 10(5), (7.86 ± 1.03) × 10(4) copies/ml, and those for the cells incubated at 56°C were (4.01 ± 0.16) × 10(5), (9.77 ± 0.97) × 10(4), (6.36 ± 0.65) × 10(4), (5.05 ± 0.24) × 10(3) copies/ml at different incubation time points. For the cells incubated at 65°C for 60 and 120 minutes, HBV DNAs were (5.15 ± 7.28) × 10(3) and (7.56 ± 10.60) × 10(2) copies/ml, respectively, which were much lower than those in the controls cells ((6.79 ± 1.48) × 10(5) copies/ml). The results of HBV DNA were different (F = 104.4, P < 0.001) in groups treated with different temperature, and results of HBV DNA were also different (F = 144.0, P < 0.001) in groups processed for different period of time. Temperature and processing time had interaction (F = 23.6, P < 0.001). After heating at 98°C for 10 minutes and boiling for 5 minutes, the HBV DNA copy number ((3.02 ± 4.26) × 10(2), (4.31 ± 6.09) × 10(2) copies/ml) in infected cells decreased by about 10 folds than that in the control group ((6.79 ± 1.48) × 10(5) copies/ml). HBV DNAs were not detected in cells that were infected by serum which was heated at 98°C for 30 minutes and boiled for 10 minutes. CONCLUSION: The infectivity of HBV serum in vitro was relatively stable at low temperature, and it would lose its infectivity in short period of time at high temperature.

Prenatal exposure to bisphenol analogues and digit ratio in children at ages 4 and 6 years: A birth cohort study.

Bisphenol analogues (BPs), including bisphenol A (BPA), have been shown to exhibit similar endocrine disrupting activities. However, epidemiological evidence on the reproductive and developmental toxicities of BPs other than BPA is scarce. The second to fourth digit ratio (2D:4D), an endocrine-sensitive endpoint, has been suggested to be a biomarker of prenatal sex steroid exposure and associated with reproductive outcomes in later life. Using the data of 545 mother-child pairs from the Shanghai-Minhang Birth Cohort Study, we prospectively assessed the effects of prenatal exposure to BPs on 2D:4D in children at ages 4 and 6 years. Single-spot urine samples were collected in the third trimester and analyzed for BPs. Digit lengths were measured using a vernier caliper in children at ages 4 and 6 years, and the 2D:4D values for both hands were calculated. A multivariable linear regression model was applied to examine associations between prenatal BPs exposure and 2D:4D digit ratios at each age separately. The generalized estimating equation (GEE) model was used to deal with repeated 2D:4D measures obtained at ages 4 and 6 years. We found that prenatal exposure to BPA alternatives including BPF, BPS, and BPAF was associated with higher digit ratio in boys and/or girls (feminizing), while TCBPA, a halogenated bisphenol, was associated with lower 2D:4D in boys (masculinizing). These associations were more pronounced at 4 years of age, and tended to remain after further considering the potential confounding from prenatal co-exposure to other BPs and childhood BPs exposure. Our study provides epidemiological evidence that BPs exposure during pregnancy may alter the digit development in children, indicative of disrupted reproductive development in later life. Given these new findings, further studies are needed to corroborate our results.