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Objective: To investigate the relationship between ambient fine particulate matter (PM2.5) exposure and fecundability. Methods: This study included 751,270 female residents from Henan Province who participated in the National Free Pre-conception Check-up Projects during 2015–2017. Ambient cycle-specific PM2.5 exposure was assessed at the county level for each participant using satellite-based PM2.5 concentration data at 1-km resolution. Cox proportional hazards models with time-varying exposure were used to estimate the association between fecundability and PM2.5 exposure, adjusted for potential individual risk factors. Results: During the study period, 568,713 participants were pregnant, monthly mean PM2.5 concentrations varied from 25.5 to 114.0 µg/m3 across study areas. For each 10 µg/m3 increase in cycle-specific PM2.5, the hazard ratio for fecundability was 0.951 (95 % confidence interval: 0.950–0.953). The association was more pronounced in women who were older, with urban household registration, history of pregnancy, higher body mass index (BMI), hypertension, without exposure to tobacco, or whose male partners were older, with higher BMI, or hypertension. Conclusion: In this population-based prospective cohort, ambient cycle-specific PM2.5 exposure was associated with reduced fecundability. These findings may support the adverse implications of severe air pollution on reproductive health.

Anthocyanin accumulation is acknowledged as a phenotypic indicator of phosphate (Pi) starvation. However, negative regulators of this process and their molecular mechanisms remain largely unexplored. In this study, we demonstrate that WRKY33 acts as a negative regulator of phosphorus-status-dependent anthocyanin biosynthesis. WRKY33 regulates the expression of the gene encoding dihydroflavonol 4-reductase (DFR), a rate-limiting enzyme in anthocyanin production, both directly and indirectly. WRKY33 binds directly to the DFR promoter to repress its expression and also interferes with the MBW complex through interacting with PAP1 to indirectly influence DFR transcriptional activation. Under −Pi conditions, PHR1 interacts with WRKY33, and the protein level of WRKY33 decreases; the repression of DFR expression by WRKY33 is thus attenuated, leading to anthocyanin accumulation in Arabidopsis. Further genetic and biochemical assays suggest that PHR1 is also involved in regulating factors that affect WRKY33 protein turnover. Taken together, our findings reveal that Pi starvation represses WRKY33, a repressor of anthocyanin biosynthesis, to finely tune anthocyanin biosynthesis. This “double-negative logic” regulation of phosphorus-status-dependent anthocyanin biosynthesis is required for the maintenance of plant metabolic homeostasis during acclimation to Pi starvation.

Exposure to greenness may lead to a wide range of beneficial health outcomes. However, the effects of greenness on preterm birth (PTB) are inconsistent, and limited studies have focused on the subcategories of PTB. A total of 3,751,672 singleton births from a national birth cohort in mainland China were included in this study. Greenness was estimated using the satellite-based Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index with 500-m and 1,000-m buffers around participants’ addresses. The subcategories of PTB (20–36 weeks) included extremely PTB (EPTB, 20–27 weeks), very PTB (VPTB, 28–31 week), and moderate-to-late PTB (MPTB, 32–36 weeks). Gestational age (GA) was included as another birth outcome. We used logistic regression models and multiple linear regression models to analyze these associations throughout the entire pregnancy. We found inverse associations between greenness and PTB and positive associations between greenness and GA. Specifically, an increase of 0.1 NDVI exposure within a 500-m buffer throughout the entire pregnancy was significantly associated with decreases in PTB (odds ratio [OR], 0.930; 95% confidence interval [CI], 0.927–0.932), EPTB (OR, 0.820; 95% CI, 0.801–0.839), VPTB (OR, 0.913; 95% CI, 0.908–0.919), MPTB (OR, 0.934; 95% CI, 0.931–0.936), and an increase in GA (β = 0.050; 95% CI, 0.049–0.051 weeks). These results suggest the potential protective effects of greenness on PTB and its subcategories: MPTB, VPTB, and EPTB in China.

Summary: Fruit softening indicated by firmness determines the texture, transportability, and shelf life of tomato products. However, the regulatory mechanism underlying firmness formation in tomato fruit is poorly understood. Here, we report the regulatory role of SlBES1, an essential component of brassinosteroid hormone signaling, in tomato fruit softening. We found that SlBES1 promotes fruit softening during tomato fruit ripening and postharvest storage. RNA-seq analysis suggested that PMEU1, which encodes a pectin methylesterase, might participate in SlBES1-mediated softening. Biochemical and immunofluorescence assays indicated that SlBES1 inhibited PMEU1-related pectin de-methylesterification. Further molecular and genetic evidence verified that SlBES1 directly binds to the E-box of PMEU1 to repress its expression, leading to fruits softening. Loss-of-function SlBES1 mutant generated by CRISPR-Cas9 showed firmer fruits and longer shelf life during postharvest storage without other quality alteration. Collectively, our results indicated the potential of manipulating SlBES1 to regulate firmness without negative consequence on visual and nutrition quality.

Background: Most evidences regarding ambient PM2.5 or PM10 (particulate matter of median aerodynamic diameter ≤2.5 μm or ≤10 μm) and preterm birth (PTB) come from western countries which has relatively low PM pollution exposure, and the results are still inconsistent. This study aims to examine whether exposure to high concentrations of PM2.5 or PM10 was associated with PTB (

Objectives: Infection with rubella virus during pregnancy can result in congenital defects and adverse pregnancy outcomes. The risk of rubella infection is greatly determined by the level of rubella antibodies in the serum. A survey of rubella antibody seronegativity rates was conducted in 780 000 women in rural China who were planning a pregnancy, in order to evaluate the herd susceptibility in different age groups and by high, middle, and low GDP per capita regions. Methods: In order to evaluate the herd susceptibility to rubella, a nationwide population-based study of rural Chinese women who were planning to have a baby and who were aged 21–49 years was instigated. As a part of the National Free Pre-conception Health Examination Project covering 29 provinces in 2012, a physical check-up program was provided to women who planned to become pregnant within the next 6 months. All medical data were from serological samples tested by ELISA, and the participants’ immunity status was categorized based on levels of rubella antibodies. Economic data were also collected to explore the association between herd susceptibility and socioeconomic characteristics in the women of childbearing age. Results: A total 264 306 of 782 293 recruited women preparing for pregnancy tested susceptible to rubella (33.79%). The seronegativity rate in women with a history of vaccination was significantly lower than that in women who had not received the vaccination or did not know their vaccination history (23.76%, 33.70%, and 35.68%, respectively). The seronegativity rates were 26.89%, 37.86%, and 32.61% in high, middle, and low GDP per capita areas, respectively. After stratified analysis and adjusting for other factors by multiple logistic regression, the lower seronegativity rates in women in high GDP per capita regions compared to women in middle and low GDP per capita regions remained in the different age groups and subgroups of immunization history. Conclusions: There is a clear difference in rubella-specific susceptibility among rural women preparing for pregnancy of different sociodemographic and economic backgrounds. The number of rubella-susceptible rural women preparing for pregnancy, especially in relatively low GDP per capita regions in China, was high. Offering rubella vaccination to women who are rubella-susceptible and who plan to become pregnant should become one of the priorities in the field of public health work in China.

Background: Preterm birth is the leading cause of child death in children younger than 5 years. Large cohort studies in developed countries have shown that maternal hepatitis B virus infection is associated with preterm birth, but there is little reliable evidence from China and other developing countries, where hepatitis B virus prevalence is intermediate or high. Hence, we designed this study to investigate the association between pre-pregnancy hepatitis B virus infection and risk of preterm and early preterm birth. Methods: Between Jan 1, 2010, and Dec 31, 2012, we did a population-based cohort study using data from 489 965 rural women aged 21–49 years who had singleton livebirths from 220 counties of China who participated in the National Free Preconception Health Examination Project. Participants were divided into three groups according to their pre-pregnancy status of hepatitis B virus infection: women uninfected with hepatitis B virus (control group), women who were HBsAg positive and HBeAg negative (exposure group 1), and women who were both HBsAg and HBeAg positive (exposure group 2). The primary outcome was preterm birth (gestation at less than 37 weeks). We used log-binomial regression to estimate adjusted risk ratios (aRR) of preterm birth for women with pre-pregnancy hepatitis B virus infection, and risk of early preterm birth (gestation less than 34 weeks). Findings: 489 965 women met inclusion criteria and were included in this study; of these, 20 827 (4·3%) were infected with hepatitis B virus. Compared with women who were not infected with hepatitis B virus, women who were HBsAg positive and HBeAg negative had a 26% higher risk of preterm birth (aRR 1·26, 95% CI 1·18–1·34) and women who were both HBsAg and HBeAg positive had a 20% higher risk of preterm birth (aRR 1·20, 1·08–1·32). Compared with women who were not infected with hepatitis B virus, women who were HBsAg positive and HBeAg negative manifested an 18% higher risk of early preterm birth (gestation less than 34 weeks; aRR 1·18, 1·04–1·34) and women who were both HBsAg and HBeAg positive had a 34% higher risk of early preterm birth (aRR 1·34, 1·10–1·61). Maternal pre-pregnancy hepatitis B virus infection was independently associated with higher risk of preterm birth and early preterm birth. These associations were similar in subgroups of participants as defined by baseline characteristics. Interpretation: Besides mother-to-child transmission, the risk of preterm birth in women infected with hepatitis B virus should not be neglected. Comprehensive programmes that focus on early detection of hepatitis B virus infection before pregnancy and provide appropriate medical intervention for women infected with hepatitis B virus before and during pregnancy would be helpful in improving maternal and neonatal outcomes and reducing child mortality. Funding: Chinese Association of Maternal and Child Health Studies.