Maternal periconceptional folic acid supplementation and risk for fetal congenital genitourinary system defects.

BACKGROUND: Taking folic acid supplementation could reduce the risk of neural tube defects for offspring in the maternal periconceptional period, but the relationship between folic acid use and other birth defects remains unclear, such as genitourinary system birth defects. METHODS: The data from a Prenatal Health Care System and Birth Defects Surveillance System in Tongzhou, Beijing, China, were collected from 2013 to 2018. We adjusted for differences in characteristics between comparison groups using propensity score inverse probability weighting and assessed associations with Poisson regression modeling. RESULTS: A total of 65,418 live births and stillbirths were included, and there were 194 cases with congenital genitourinary defects among them. The prevalence of genitourinary system birth defects was 29.2 (34.9) per 10,000 for FA/MMFA users (nonusers). Compared to nonusers, FA/MMFA users had a lower risk for genitourinary system birth defects (adjusted risk ratio [aRR] 0.81, 95% confidence interval [CI] 0.67, 0.98), and for hypospadias (aRR 0.55, 95% CI 0.40, 0.76). CONCLUSIONS: FA or MMFA supplementation during the maternal periconceptional period could reduce the risk for genitourinary system birth defects in offspring. More mechanisms should be explored for the protective effect. IMPACT: Folic acid (FA) or multiple micronutrients containing folic acid (MMFA) supplementation during the maternal periconceptional period could reduce the risk for genitourinary system birth defects in offspring. Maternal FA/MMFA supplementation during the periconceptional period may reduce the risk for hypospadias.

Vitamin D nutritional status in early pregnancy and its relationship with periconceptional multiple micronutrients supplementation.

BACKGROUND AND OBJECTIVES: To assess the vitamin D nutritional status (VDN) of pregnant women in early pregnancy and investigate the effects of periconceptional supplementation with multiple micronutrients (MMs) on this status. METHODS AND STUDY DESIGN: Data were taken from the Pregnancy Health Care System and Hospital Information System in 2018 in Beijing. Vitamin D nutritional status in early pregnancy was evaluated among 4,978 pregnant women, and 4,540 women who took folic acid only (FA) or multiple mi-cronutrients supplements (MM) during the periconceptional period, were include to estimate the associations between periconceptional supplementation with MM and prevalence of vitamin D deficiency or insufficiency with logistic regression model. RESULTS: The mean early-pregnancy vitamin D concentration was 18.6 (±7.5) ng/mL, and the rates of deficiency and insufficiency were 31.6% and 60.5%, respectively. Compared to the FA group, the adjusted odds ratio (aOR, 95%confidence interval, CI) for insufficiency or deficiency of the MM group were 0.25(0.18-0.34), and the aOR (95%CI) for deficiency of the MM group were 0.17 (0.12-0.23). Women who took MMs for a longer period of time, at higher frequencies, and with higher compliance scores had lower rates of deficiency and insufficiency. In winter, spring, and autumn, taking MMs could reduce deficiency by about 70%; in summer, there was little effect. CONCLUSIONS: Among women in Beijing, serum concentrations of vitamin D in early pregnancy are relatively low, and the rates of deficiency and insufficiency are high. Taking MMs during the periconceptional period could improve this situation.

Maternal Periconceptional Folic Acid Supplementation and Risk for Fetal Congenital Heart Defects.

OBJECTIVE: To determine the effects of maternal periconceptional supplementation with folic acid or multiple micronutrients containing folic acid on the prevention of fetal congenital heart defects (CHDs). STUDY DESIGN: Data were drawn from a Prenatal Health Care System and a Birth Defects Surveillance System in a district of Beijing, China. A total of 63 969 singleton births, live or stillborn, 308 CHDs among them, during 2013 to 2018 were included. Associations between different patterns of supplementation and risk for total CHDs or main types of CHDs were evaluated with risk ratios (RRs). RESULTS: For folic acid or multiple micronutrients containing folic acid users compared with nonusers, the adjusted RRs (ARRs) for total CHDs, critical CHD, and ventricular septal defect (VSD) were 0.60 (95% CI, 0.44-0.83), 0.41 (95% CI, 0.26-0.67), and 0.47 (95% CI, 0.30-0.74), respectively. When we compared multiple micronutrients containing folic acid users with folic acid users, the ARRs were 0.84 (95% CI, 0.66-1.09), 0.64 (95% CI, 0.41-1.00), and 0.94 (95% CI, 0.63-1.41) for total CHDs, critical CHD, and VSD, respectively. We also found that, compared with supplementation initiated after conception, supplementation initiated before conception was associated with a lower risk for CHDs: the ARRs were 0.68 (95% CI, 0.48-0.95) for total CHDs and 0.26 (95% CI, 0.10-0.71) for critical CHD, but 1.08 (95% CI, 0.63-1.83) for VSD. CONCLUSIONS: Maternal periconceptional supplementation with folic acid or multiple micronutrients containing folic acid seems to decrease the risk for CHDs, especially critical CHD, in offspring. Supplementation confers a greater protective effect when it is initiated before conception. We did not find any difference between folic acid and multiple micronutrients containing folic acid in terms of preventing CHDs.

lncRNA SNHG11 Promotes Gastric Cancer Progression by Activating the Wnt/ß-Catenin Pathway and Oncogenic Autophagy.

Long non-coding RNAs (lncRNAs) are under active investigation in the development of cancers, including gastric cancer (GC). Oncogenic autophagy is required for cancer cell survival. The present study aimed to investigate the regulatory role of lncRNA small nucleolar host gene 11 (SNHG11) in GC. We show that SNHG11 is upregulated in GC, and that its upregulation correlated with dismal patient outcomes. Functionally, SNHG11 aggravated oncogenic autophagy to facilitate cell proliferation, stemness, migration, invasion, and epithelial-to-mesenchymal transition (EMT) in GC. Mechanistically, SNHG11 post-transcriptionally upregulated catenin beta 1 (CTNNB1) and autophagy related 12 (ATG12) through miR-483-3p/miR-1276, while the processing of precursor (pre-)miR-483/pre-miR-1276 was hindered by SNHG11. SNHG11 induced GSK-3ß ubiquitination through interacting with Cullin 4A (CUL4A) to further activate the Wnt/ß-catenin pathway. Intriguingly, SNHG11 regulated autophagy in a manner dependent on ATG12 rather than the Wnt/ß-catenin pathway, whereas SNHG11 contributed to the malignant behaviors of GC cells via both pathways. Finally, SNHG11 upregulation in GC cells was shown to be transcriptionally induced by TCF7L2. In conclusion, we reveal that SNHG11 is an onco-lncRNA in GC and might be a promising prognostic and therapeutic target for GC.

Maternal periconceptional folic acid supplements use and fetus risk for limb defects.

BACKGROUND: Associations between the periconceptional folic acid only (FAO) or multiple micronutrients containing folic acid (MMFA) supplementation and risk for limb defects are inconsistent. OBJECTIVE: To explore the association between periconceptional folic acid supplements use and risk for limb defects, including clubfoot, polydactyly, syndactyly, and limb deficiencies. METHODS: Data were derived from a cohort based on a pregnancy registry in a district of Beijing, China, from 2013 to 2018. Information on maternal periconceptional FAO and MMFA supplementation was collected via face-to-face interviews at first trimester. Pregnancy outcomes including limb defects were ascertained in livebirths, stillbirths, and elective pregnancy terminations and were recorded into the system. Propensity score methods were used to adjust for potential confounders. RESULTS: A total of 63 969 women with a singleton delivery were included. The overall prevalence of limb defects was 47.5 per 10 000 (n = 63 969) singleton deliveries. Decreased prevalence of limb defects was found among FAO/MMFA users compared with women who did not take supplements (nonusers) (46.1 vs. 61.9 per 10 000 births, adjusted risk ratio [RR] 0.80, 95% confidence interval [CI] 0.56, 1.12). Compared with nonusers (n = 6462, 10.2%), women who took either FAO (n = 26 567, 42.0%) or MMFA (n = 30 259, 47.8%) had a lower risk for total clubfoot (RR 0.40, 95% CI 0.20, 0.84), and for isolated clubfoot (RR 0.41, 95% CI 0.17, 0.97). For other limb defects except clubfoot, FAO supplementation did not appear to be associated with reduced risk, while MMFA supplementation group had 30%-50% reduced risks for other limb defects. A lower risk for limb defects or isolated limb defects was found with MMFA supplementation when FAO supplementation was used as a control. CONCLUSIONS: Maternal periconceptional supplements with either FAO or MMFA had inverse association with clubfoot in offspring, and MMFA was associated with lower risk for isolated limb defects compared with FAO.

Concentrations and distribution of novel brominated flame retardants in the atmosphere and soil of Ny-Ålesund and London Island, Svalbard, Arctic.

Novel brominated flame retardants (NBFRs) were investigated in Arctic air and soil samples collected from Ny-Ålesund and London Island, Svalbard, during Chinese scientific research expeditions to the Arctic during 2014-2015. The concentrations of Σ9NBFRs in the Arctic air and soil were 4.9-8.7 pg/m3 (average 6.8 pg/m3) and 101-201 pg/g dw (average 150 pg/g dw), respectively. The atmospheric concentration of hexabromobenzene (HBB) was significantly correlated with that of pentabromotoluene (PBT) and pentabromobenzene (PBBz), suggesting similar source and environmental fate in the Arctic air. No significant spatial difference was observed among the different sampling sites, both for air and soil samples, indicating that the effects of the scientific research stations on the occurrence of NBFRs in the Arctic were minor. The fugacities from soil to air of pentabromoethylbenzene (PBEB), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE), and decabromodiphenylethane 1,2-bis (pentabromophenyl) ethane (DBDPE) were lower than the equilibrium value, indicating a nonequilibrium state of these compounds between air and soil, the dominant impact of deposition and the net transport from air to soil. The correlation analysis between the measured and predicted soil-atmosphere coefficients based on the absorption model showed that the impact of the soil organic matter on the distribution of NBFRs in the Arctic region was minor. To the best of our knowledge, this work is one of the limited reports on atmospheric NBFRs in the Arctic and the first study to investigate the occurrence and fate of NBFRs in the Arctic soil.

Long noncoding RNA FOXD3-AS1 promotes colon adenocarcinoma progression and functions as a competing endogenous RNA to regulate SIRT1 by sponging miR-135a-5p.

More and more documents have proved that the abnormal expression of long noncoding RNAs (lncRNAs) are correlated with the initiation and progression of colorectal cancer (CRC). lncRNA FOXD3-AS1 has been reported in glioma for its oncogenic property. According to the survival analysis of The Cancer Genome Atlas database, FOXD3-AS1 upregulation implied lower survival rate of patients with CRC. Quantitative real-time polymerase chain reaction showed the overexpression of FOXD3-AS1 in both CRC tissues and cells. The Kaplan-Meier method demonstrated the prognostic value of FOXD3-AS1 for patients with CRC. To explore the effect of FOXD3-AS1 on CRC progression, loss-of-function experiments were carried out, whose results indicated that knockdown of FOXD3-AS1 suppressed cell proliferation, migration, and invasion, inhibited cell cycle and promoted cell apoptosis in vitro. In vivo experiments affirmed that FOXD3-AS1 affected tumor growth. FOXD3-AS1 expression was enriched in the cytoplasm of CRC cells. Mechanism experiments revealed that FOXD3-AS1 served as a competing endogenous RNA to upregulate SIRT1 by sponging miR-135a-5p. In addition, SIRT1 silencing also restrained cell proliferation and motility. Rescue assays revealed the biological function of FOXD3-AS1/miR-135a-5p/SIRT1 axis in CRC progression. In conclusion, FOXD3-AS1 promotes CRC progression by regulating miR-135a-5p/SIRT1 axis, shedding lights on the way to CRC treatments.

Rab GTPase 21 mediates caerulin-induced TRAF3-MKK3-p38 activation and acute pancreatitis response.

Acute pancreatitis (AP) is a severe inflammatory disease. Caerulin induces significant pro-inflammatory responses in macrophages, causing serve damage to pancreatic acinar cells. The potential role of Rab GTPase 21 (Rab21) in this process was tested in this study. In murine bone marrow-derived macrophages (BMDMs), caerulin induced Rab21-TRAF3-MKK3 complex association. Rab21 silencing (by targeted shRNAs) or knockout (by CRISPR/Cas9 method) largely inhibited caerulin-induced MKK3-TRAF3 association, downstream MKK3-p38 activation and production of several pro-inflammatory cytokines (IL-1ß, TNF-α and IL-17). Conversely, ectopic Rab21 overexpression in BMDMs potentiated caerulin-induced MKK3-TRAF3 association and pro-inflammatory cytokines production. The cytotoxicity of caerulin-activated BMDMs to co-cultured pancreatic acinar cells was alleviated by Rab21 knockdown or knockout, but exacerbated with Rab21 overexpression. In vivo, administration of Rab21 shRNA lentivirus significantly attenuated pancreatic and systemic inflammations in caerulin-injected AP mice. Collectively, our results suggest that Rab21 mediates caerulin-induced MKK3-p38 activation and pro-inflammatory responses.

Seasonal variation and human exposure assessment of legacy and novel brominated flame retardants in PM2.5 in different microenvironments in Beijing, China.

Indoor exposure to legacy and novel brominated flame retardants (NBFRs) may cause potential risks to human health. Studies on seasonal variations of indoor PM2.5-bound BFRs are scant. This study comprehensively investigated the seasonal variations of PM2.5-bound polybrominated diphenyl ethers (PBDEs) and NBFRs in various indoor environments (i.e. activity room, dormitory, home and office) and outdoor PM2.5 in Beijing, China over one year. The levels of PBDE (226 ±â€¯108 pg m-3) were higher than that of NBFRs (27.0 ±â€¯16.0 pg m-3) in all indoor environments. Decabromodiphenyl ether (BDE-209) and decabromodiphenyl ethane (DBDPE) were the most abundant BFRs. Office showed the highest mean concentrations of Σ15PBDEs (251 ±â€¯125 pg m-3) and Σ9NBFRs (33.0 ±â€¯18.0 pg m-3), which may be related to the higher number density of indoor materials. The concentrations of Σ9NBFRs and Σ15PBDE in indoor PM2.5 were found to be significantly higher than those in the corresponding outdoor PM2.5 (p < 0.05). Two to twenty-fold seasonal variations were observed for levels of PM2.5-bound BFRs during one year, and indoor concentrations increased slightly during the central-heating period (November 2016-March 2017). Seasonal variations of BFRs could be affected by temperature, relative humidity and concentrations of particle matters. The PM2.5-bound BFRs concentrations in PM2.5 were negatively correlated with temperature and relative humidity, while positively correlated with PM2.5 concentrations (p < 0.05). Atmospheric haze pollution could possibly contribute to higher levels of indoor PM2.5-bound BFRs. Human daily intake of BFRs via PM2.5 inhalation showed seasonal differences, and the highest exposure risk occurred in winter. Toddlers were assessed to be more vulnerable to indoor PM2.5-bound BFRs in all seasons. This study provided the first-hand measurements of seasonal concentrations and human exposure to PM2.5-bound BFRs in different indoor scenarios in Beijing.

LncRNA MALAT1 induces colon cancer development by regulating miR-129-5p/HMGB1 axis.

Recent studies have exhibited significant roles of lncRNAs in various tumors' development, including colon cancer. Our study focused on the biological roles of lncRNA MALAT1 in colon cancer. In our study, it was demonstrated that MALAT1 was upregulated in human colon cancer cell lines including Lovo, HCT116, SW480, and HT29 cells compared to the normal human intestinal epithelial HIEC cells. Moreover, we observed that miR-129-5p was downregulated in colon cancer cells with a significant increase of HMGB1 expression. Inhibition of MALAT1 can inhibit the proliferation of colon cancer SW480 and HCT116 cells and next, bioinformatics analysis was used to predict the target microRNA of MALAT1. miR-129-5p was identified and confirmed as a direct regulator of MALAT1 and it was shown that miR-129-5p mimics were able to restrain the progression of colon cancer cells. In addition, high motility group box protein 1 (HMGB1), was predicted as a mRNA target of miR-129-5p. Furthermore, we found that MALAT1 exerted its biological functions through regulating HMGB1 by sponging miR-129-5p in vitro. Silencing MALAT1 greatly inhibited HMGB1 expression which can be reversed by miR-129-5p inhibitors. It was indicated in our investigation that MALAT1 may serve as a competing endogenous lncRNA (ceRNA) to mediate HMGB1 by sponging miR-129-5p in colon cancer. Taken together, our results indicated that MALAT1/miR-129-5p/HMGB1 axis could be provided as an important prognostic biomarker in colon cancer development.

Dihydromyricetin inhibits caerulin-induced TRAF3-p38 signaling activation and acute pancreatitis response.

Acute pancreatitis (AP) is a common inflammatory disease in gastrointestinal tract. Our previous study has shown that caerulin induces TNF receptor-associated factor 3 (TRAF3)-p38 signaling activation and pro-inflammatory response in macrophages, causing damage to co-cultured pancreatic acinar cells. Dihydromyricetin (DHM) is a flavonoid extracted from Ampelopsis grossedentata, which has displayed anti-inflammation and anti-oxidant functions. Our results here show that DHM potently inhibited caerulin-induced expression and productions of multiple pro-inflammatory cytokines (IL-1ß, TNF-α and IL-17) in murine bone marrow-derived macrophages (BMDMs). DHM significantly inhibited caerulin-induced TRAF3 protein stabilization, TRAF3-mitogen-activated protein kinase kinase 3 (MKK3) association and following MKK3-p38 activation in BMDMs. Significantly, DHM was ineffective against caerulin in TRAF3-silenced BMDMs. Importantly, DHM supplement attenuated the cytotoxicity of caerulin-activated BMDMs to co-cultured pancreatic acinar cells, resulting in significantly decreased acinar cell death and apoptosis. In vivo, DHM co-administration largely attenuated pancreatic and systemic inflammation in caerulin-injected AP mice. Together, DHM inhibits caerulin-induced TRAF3-p38 signaling activation and AP response. DHM could be further studied as a potential anti-AP agent.

Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis.

The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificated when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells.

Caerulin-induced pro-inflammatory response in macrophages requires TRAF3-p38 signaling activation.

Acute pancreatitis is a common threat to human health. Caerulin provokes severe inflammations, causing injuries to surrounding pancreatic cells. TNF receptor-associated factor 3 (TRAF3) is a highly versatile regulator of immune response. The current study aims to understand the potential effect of TRAF3 on caerulin-induced pro-inflammatory responses. In the primary-cultured mouse bone marrow-derived macrophages (BMDMs), caerulin induced TRAF3 protein stabilization, which formed a complex with mitogen-activated protein kinase kinase 3 (MKK3) to mediate downstream p38 activation. Lentiviral shRNA-mediated TRAF3 stable knockdown significantly attenuated caerulin-induced MKK3-p38 activation and production of several key pro-inflammatory cytokines, including interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and IL-17. Remarkably, TRAF3 knockdown in caerulin-stimulated BMDMs also alleviated cytotoxicity to Panc02 and primary mouse pancreatic cells. Thus, TRAF3 is required for caerulin-induced p38 activation and macrophage-mediated pro-inflammatory responses. TRAF3 expression in macrophages could be a novel therapeutic target protein for the treatment of acute pancreatitis.

[Clinical analysis of uterine rupture during pregnancy].

OBJECTIVE: To explore the clinical characteristics of pregnant uterine rupture, enhance its early diagnosis rate and improve its prognosis. METHODS: For this retrospective study, a total of 55 143 delivery cases at Tongzhou District Maternal & Child Health Hospital from January 1, 2003 to May 31, 2012 was analyzed. There were 2490 cases of scarred uterus and 68 cases had uterine rupture. And 62 of them belonged to scarred uterus rupture. And there were 52 653 cases of non-scarred uterus childbirth and 6 of them had rupture. RESULTS: Significant differences existed in the rupture of scarred versus non-scarred uterus and maternal versus primipara women. Uterus rupture usually occurred at the incomplete rupture position of original surgical scar at 39 weeks or more. The scar thickness of lower uterine segment was ≤ 3 mm on ultrasound. Three cases with laparoscopic myoma removal within 1 year had complete rupture at 36-38 weeks. Postpartum hemorrhage incidence was 42.65%. There were two cases of hysterectomy and 11 cases of neonatal asphyxia. CONCLUSION: For second pregnancy of cesarean section, pregnancy should be terminated before 39 weeks if scar thickness of lower uterine segment is ≤ 3 mm. Late rupture is to be monitored closely for those with laparoscopic myoma removal within 1 year. Meanwhile, we should strengthen the management of migrant and unemployed women.

The relationship between maternal periconceptional micronutrient supplementation and non-syndromic cleft lip/palate in offspring.

BACKGROUND: This study aimed to explore the relationship between maternal periconceptional supplementation with folic acid only (FAO) or with multiple micronutrients containing folic acid (MMFA) and non-syndromic cleft lip/palate in offspring. METHOD: The data came from a prenatal health care system and a birth defects surveillance system in Beijing, China, from 2013 to 2018. Information on maternal FAO/MMFA supplementation was collected by questionnaire in the first trimester, and data on cleft lip/palate were collected at delivery or termination of pregnancy. Inverse probability weighting (IPW) by the propensity score to adjust for the confounders and Poisson regression model was used to estimate risk ratios (RRs) and their 95% confidence intervals (CIs). RESULTS: A total of 63,969 participants were included in the study. Compared to the no-supplementation group, the adjusted RR for the supplementation group was 0.51 (95% CI: 0.40, 0.64). And the adjusted RRs for FAO and MMFA compared to the no-supplementation group were 0.56 (95% CI: 0.40, 0.76) and 0.48 (95% CI: 0.35, 0.65), respectively. Compared to supplement FAO and MMFA with less than 8 days out of 10 days, the adjusted RRs for FAO and MMFA with 8 or more days out of 10 days were 1.17 (95% CI: 0.78, 1.75), and 2.05 (95% CI: 1.37, 3.31), respectively. CONCLUSION: Maternal supplementation with micronutrients, either FAO or MMFA, during the periconceptional period can reduce the risk for non-syndromic cleft lip/palate in offspring. However, women should be more cautious with MMFA supplementation.

Chronic Hemorrhagic Anemia Caused by Hookworm Infection: A Case Report.

PURPOSE: Hookworm infection is one of the causes of long-term chronic hemorrhagic anemia in patients. This article reports a case of chronic severe anemia caused by hookworm infection. METHODS: The capsule endoscopy showed that there were a large number of hookworms in the small intestine of a patient. At the same time, using the technique of saturated brine floatation and the automatic stool analyzer, hookworm eggs were detected. RESULTS: The patient's anemia was caused by hookworm infection and was significantly improved after anti-hookworm treatment. CONCLUSION: Hookworm infection cannot be ignored in the differential diagnosis of patients with chronic anemia. Capsule endoscopy combined with stool detection haves an important clinical value for the diagnosis of hookworm disease.

Source identification of PCBs in Antarctic air by compound-specific isotope analysis of chlorine (CSIA-Cl) using HRGC/HRMS.

Occurrence of persistent organic pollutants (POPs) in the Polar Regions has received great concern in the past several decades due to their long-term adverse effect on biological health in such a fragile environment. However, there is still argument over their source and fate in these pristine areas. Here we attempted to use a novel approach (compound-specific isotope analysis of chlorine, CSIA-Cl) to identify the source of POPs in Antarctic air by comparison with the source area. The results showed that the relative isotope-ratio variation of Cl (δ37Cl') values showed a large variation from - 137 to 9.04 ‰ in the gas-phase samples, and a significantly negative correlation (p < 0.01) was obtained against the logKoa values of PCBs. There were no significant correlations (p > 0.05) observed between the δ37Cl' values and meteorological parameters except for PCB-28 which showed temperature dependence. By contrast, the δ37Cl' values in the urban (Beijing) air ranged from - 12.8 to 2.03 ‰. The larger variation of δ37Cl' in Antarctic air indicated evidently influence of long-range atmospheric transport (LRAT) on isotopologue fractionation of PCBs. This study may shed light on the application of CSIA-Cl for source identification of chlorinated POPs on a large scale.

Modification effects of ambient temperature on associations of ambient ozone exposure before and during pregnancy with adverse birth outcomes: A multicity study in China.

BACKGROUND: Epidemiological studies suggest that both ambient ozone (O3) and temperature were associated with increased risks of adverse birth outcomes. However, very few studies explored their interaction effects, especially for small for gestational age (SGA) and large for gestational age (LGA). OBJECTIVES: To estimate the modification effects of ambient temperature on associations of ambient O3 exposure before and during pregnancy with preterm birth (PTB), low birth weight (LBW), SGA and LGA based on multicity birth cohorts. METHODS: A total of 56,905 singleton pregnant women from three birth cohorts conducted in Tianjin, Beijing and Maoming, China, were included in the study. Maximum daily 8-h average O3 concentrations of each pregnant woman from the preconception period to delivery for every day were estimated by matching their home addresses with the Tracking Air Pollution in China (TAP) datasets. We first applied the Cox proportional-hazards regression model to evaluate the city-specific effects of O3 exposure before and during pregnancy on adverse birth outcomes at different temperature levels with adjustment for potential confounders, and then a meta-analysis across three birth cohorts was conducted to calculate the pooled associations. RESULTS: In pooled analysis, significant modification effects of ambient temperature on associations of ambient O3 with PTB, LBW and LGA were observed (Pinteraction < 0.05). For a 10 µg/m3 increase in ambient O3 exposure at high temperature level (> 75th percentile), the risk of LBW increased by 28 % (HR: 1.28, 95% CI: 1.13-1.46) during the second trimester and the risk of LGA increased by 116% (HR: 2.16, 95%CI: 1.16-4.00) during the entire pregnancy, while the null or weaker association was observed at corresponding low (≤ 25th percentile) and medium (> 25th and ≤ 75th percentile) temperature levels. CONCLUSION: This multicity study added new evidence that ambient high temperature may enhance the potential effects of ambient O3 on adverse birth outcomes.

Prevalence of gestational diabetes mellitus and its determinants among pregnant women in Beijing.

OBJECTIVE: To investigate the prevalence of gestational diabetes mellitus (GDM) and its determinants among pregnant women in the Tongzhou district of Beijing, China. METHODS: This study was performed on data collected in the routine work of the prenatal health care system from 27,119 pregnant women in the Tongzhou district of Beijing during 2013-2018. Univariate and multivariate logistic regression analyses were used to assess the factors associated with GDM. RESULTS: The overall prevalence of GDM was 24.24%, and it showed an increasing trend over the 6 years. A univariate analysis showed that the prevalence of GDM increased with age (p < .001). In multivariate analysis, it was found that women with a non-local household registration, as well as those without a local household registration but whose husbands had one, had a lower risk for GDM than both spouses who had local registration. Women who were overweight/obese had a higher risk for GDM than women with a normal pre-pregnancy body mass index. Multipara women had a lower likelihood of developing GDM. CONCLUSIONS: We found a slightly higher prevalence of GDM in the Tongzhou district of Beijing than has been found in other studies, and the prevalence rose over the 6 years of the study. Advanced age, pre-pregnancy overweight or obesity, and local household registration were important risk factors for GDM. Multiparity may be a protective factor against developing GDM. Intensive health education on related determinants should be strengthened for the prevention and control of GDM, especially in high-risk women.

Periconceptional Folic Acid Supplementation and Newborn Birth Weights.

Background: The relationship between maternal folic acid supplementation and the birth weights of offspring remains inconclusive. Aim: To examine the associations between maternal supplementation with folic acid only (FAO) or multiple micronutrients containing folic acid (MMFA) and newborn birth weights, as well as the risk of small for gestational week age (SGA) and large for gestational week age (LGA) newborns. Methods: Data on 31,107 births from 2015 to 2018 were extracted from the population-based prenatal health care system in a district of Beijing. Generalized linear and logistic regression models were used to evaluate the association between maternal periconceptional folic acid supplementation and birth weights or with risk of small for gestational week age (SGA) and large for gestational week age (LGA). Results: Compared with newborns whose mothers did not use any folic acid supplements, the newborns with maternal periconceptional folic acid supplementation had similar median birth weight but had a lower risk of SGA [adjusted odds ratio (aOR) = 0.81 (95% CI: 0.68-0.97)], however newborns born to mothers who took multiple micronutrients with folic acid (MMFA) with high compliance had a 25.59 g (95% CI: 6.49-44.69) higher median birth weight. Periconceptional women took folic acid only (FAO) (aOR = 0.83; 95%CI: 0.67-1.01) or MMFA (aOR = 0.74; 95%CI: 0.60-0.91) with high compliance decreased the risk of SGA, but has no impact on the risk of LGA. Conclusion: Periconceptional FAO supplementation has no impact on the median birth weight of offspring and the risk of LGA. Compared with FAO, MMFA supplementation may increase the average birth weight, and a high compliance of supplementation with FAO or MMFA may reduce the risk of SGA, with MMFA having ad stronger effect than FAO.