Mutual Associations of Exposure to Ambient Air Pollutants in the First 1000 Days of Life With Asthma/Wheezing in Children: Prospective Cohort Study in Guangzhou, China.

BACKGROUND: The first 1000 days of life, encompassing pregnancy and the first 2 years after birth, represent a critical period for human health development. Despite this significance, there has been limited research into the associations between mixed exposure to air pollutants during this period and the development of asthma/wheezing in children. Furthermore, the finer sensitivity window of exposure during this crucial developmental phase remains unclear. OBJECTIVE: This study aims to assess the relationships between prenatal and postnatal exposures to various ambient air pollutants (particulate matter 2.5 [PM2.5], carbon monoxide [CO], sulfur dioxide [SO2], nitrogen dioxide [NO2], and ozone [O3]) and the incidence of childhood asthma/wheezing. In addition, we aimed to pinpoint the potential sensitivity window during which air pollution exerts its effects. METHODS: We conducted a prospective birth cohort study wherein pregnant women were recruited during early pregnancy and followed up along with their children. Information regarding maternal and child characteristics was collected through questionnaires during each round of investigation. Diagnosis of asthma/wheezing was obtained from children's medical records. In addition, maternal and child exposures to air pollutants (PM2.5 CO, SO2, NO2, and O3) were evaluated using a spatiotemporal land use regression model. To estimate the mutual associations of exposure to mixed air pollutants with the risk of asthma/wheezing in children, we used the quantile g-computation model. RESULTS: In our study cohort of 3725 children, 392 (10.52%) were diagnosed with asthma/wheezing. After the follow-up period, the mean age of the children was 3.2 (SD 0.8) years, and a total of 14,982 person-years were successfully followed up for all study participants. We found that each quartile increase in exposure to mixed air pollutants (PM2.5, CO, SO2, NO2, and O3) during the second trimester of pregnancy was associated with an adjusted hazard ratio (HR) of 1.24 (95% CI 1.04-1.47). Notably, CO made the largest positive contribution (64.28%) to the mutual effect. After categorizing the exposure according to the embryonic respiratory development stages, we observed that each additional quartile of mixed exposure to air pollutants during the pseudoglandular and canalicular stages was associated with HRs of 1.24 (95% CI 1.03-1.51) and 1.23 (95% CI 1.01-1.51), respectively. Moreover, for the first year and first 2 years after birth, each quartile increment of exposure to mixed air pollutants was associated with HRs of 1.65 (95% CI 1.30-2.10) and 2.53 (95% CI 2.16-2.97), respectively. Notably, SO2 made the largest positive contribution in both phases, accounting for 50.30% and 74.70% of the association, respectively. CONCLUSIONS: Exposure to elevated levels of mixed air pollutants during the first 1000 days of life appears to elevate the risk of childhood asthma/wheezing. Specifically, the second trimester, especially during the pseudoglandular and canalicular stages, and the initial 2 years after birth emerge as crucial susceptibility windows. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-ROC-17013496; https://tinyurl.com/2ctufw8n.

Associations of COVID-19 lockdown with birth weight in China.

Background: During the special period of the global spread of COVID-19, pregnant women are sensitive groups to the impacts of COVID-19 epidemic. However, the effects of lockdown measures implemented in response to the COVID-19 on fetal birthweight remain unclear. Objectives: This study investigated the associations of COVID-19 lockdown with birth weight in Chinese population. Methods: We collected 730,153 data of participants from hospitals of five cities in the south of China, we defined the time period of level I response (1/23-2/24/2020) as level I lockdown, and women who were pregnant during level I lockdown as the exposure group. Women who were pregnant during the same calendar month from 2015 to 2019 were defined as the unexposed group. We quantitatively estimate the individual cumulative exposure dose by giving different weights to days with different emergency response levels. Generalized linear regression models were used to estimate the association between COVID-19 lockdown exposure with birth weight and risk of low birth weight (<2,500 g) and macrosomia (>4,000 g). Results: The birth weight of the exposed group is heavier than the unexposed group (3,238.52 vs. 3,224.11 g: adjusted ß = 24.39 g [95% CI: 21.88, 26.91 g]). The exposed group had a higher risk of macrosomia (2.8% vs. 2.6%; adjusted OR = 1.17 [95% CI: 1.12, 1.22]). More obvious associations were found between COVID-19 lockdown and macrosomia in women who experienced the lockdown in their early pregnancy. Women who experienced the lockdown at their 4-7 weeks of pregnancy showed statistically significant heavier birth weight than unexposed group (after adjustment): ß = 1.28 (95% CI: 1.11, 1.46) g. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown in all pregnant women and birth weight, after divided into four groups, Q1: ß = 32.95 (95% CI: 28.16, 37.75) g; Q2: ß = 18.88 (95% CI: 14.12, 23.64) g; Q3: ß = 19.50 (95% CI: 14.73, 24.28) g; Q4: ß = 21.82 (95% CI: 17.08, 26.56) g. However, there was no statistically significant difference in the risk of low birth weight between exposed and unexposed groups. Conclusions: The COVID-19 lockdown measures were associated with a heavier birth weight and a higher risk of macrosomia. Early pregnancy periods may be a more susceptible exposure window for a heavier birth weight and a higher risk of macrosomia. We also observed a positive association between cumulative exposure dose of COVID-19 lockdown and birth weight. The government and health institutions should pay attention to the long-term health of the infants born during the COVID-19 lockdown period, and follow up these mothers and infants is necessary.

A Strategy for Studying Environmental Engineering: Simple Hydrothermal Synthesis of Flower-Shaped Stannous Sulfide Nanomaterials for Efficient Cataluminescence Sensing of Diethyl Ether.

In this work, flower-like stannous sulfide (SnS) nanomaterials are synthesized using a hydrothermal method and used as sensitive materials for cataluminescence (CTL)-based detection of diethyl ether. Gas sensors based on SnS nanomaterials are prepared, and the SnS nanomaterials exhibit excellent gas-sensitive behavior towards ether. High sensitivity to ether is achieved at a relatively low operating temperature (153 °C) compared to other common sensors. The response time is 3 s and the recovery time is 8 s. The CTL intensity shows a good linear relationship (R2 = 0.9931) with a detection limit of 0.15 ppm and the concentration of ether in the range of 1.5-60 ppm. The proposed CTL sensor shows good selectivity towards ether. In addition, a highly stable signal is obtained with a relative standard deviation of 1.5%. This study indicates that the SnS-based sensor has excellent gas-sensitive performance and shows potential for applications in the detection of ether.

Long-term exposure to ambient ozone and cardiovascular diseases: Evidence from two national cohort studies in China.

INTRODUCTION: The health effects of ambient ozone have been investigated in many previous studies. However, the effects of long-term exposure to ambient ozone on the incidence of cardiovascular disease (CVD) remain inconclusive. OBJECTIVES: To estimate the associations of long-term exposure to maximum daily 8-hours average ozone (MDA8 O3) with the incidence of total CVD, heart disease, hypertension, and stroke. METHODS: This was a prospective cohort study, and the data was obtained from the China Health and Retirement Longitudinal Survey (CHARLS) implemented during 2011-2018 and the China Family Panel Studies (CFPS) implemented during 2010-2018. We applied a Cox proportional hazards regression model to evaluate the associations of MDA8 O3 with total CVD, heart disease, hypertension, and stroke risks, and the corresponding population-attributable fractions (PAF) attributable to MDA8 O3 were also calculated. All analyses were conducted by R software. RESULTS: The mean MDA8 O3 concertation of all included participants in the CHARLS and CFPS were 51.03 part per billion (ppb) and 51.15 ppb, respectively. In the CHARLS including 18,177 participants, each 10 ppb increment in MDA8 O3 concentration was associated with a 31% increase [hazard ratio (HR) = 1.31, 95% confidence interval (CI): 1.22-1.42] in the risk of incident heart disease, and the corresponding population-attributable fractions (PAF) was 13.79% [10.12%-17.32%]. In the CFPS including 30,226 participants, each 10 ppb increment in MDA8 O3 concentration was associated with an increase in the risk of incident total CVD (1.07 [1.02-1.13]), and hypertension (1.10 [1.03-1.18]). The PAFs of total CVD, and hypertension attributable to MDA8 O3 were 3.53% [0.82%-6.16%], and 5.11% [1.73%-8.38%], respectively. Stratified analyses showed greater associations in males, urban areas, and Southern China. CONCLUSIONS: Long-term exposure to MDA8 O3 may increase the incidence of CVD. Therefore, the policies that control O3 and related precursors are persistently needed.

[Effect of electroacupuncture on the expression of Iba-1 in spinal dorsal horn and hippocampus of chronic pain rats with knee osteoarthritis].

OBJECTIVE: To observe the effect of electroacupuncture(EA) on pain-ralated behaviors, morphology of hippocampus, concentrations of inflammatory cytokines and expression of ionized calcium binding adapter molecule 1(Iba-1) in dorsal horn of the spinal cord and the hippocampus, and brain-derived neurotrophic factor (BDNF) in hippocampus of rats with knee osteoarthritis (KOA), so as to explore the mechanism of EA in improving chronic pain of KOA. METHODS: Forty SD rats were randomly divided into blank group, saline group, model group and EA group, with 10 rats in each group. Monosodium iodoacetate(MIA, 80 mg/mL, 50 µL) was injected into the left knee joint cavity of rats in the model group and EA group to establish the chronic pain model of KOA, while the same volume of normal saline was injected into the left knee joint cavity of rats in the saline group. Rats in the EA group received EA stimulation(2 Hz/100 Hz, 1-2 mA) at left "Yanglingquan"(GB34) and "Neixiyan"(EX-LE4) for 15 min, 14 d after MIA injection. The treatment was given once daily, 5 d as 1 session and 2 sessions of treatment were required. Methanical withdrawl threshold(MWT) and weight-bearing capacity tests on left hind limbs were carried out 1 d before, 7 d，14 d, 20 d and 26 d after MIA injection. At the 27th day, rats were sacrificed and HE staining was used to observe the morphology of hippocampal CA1 area. Concentrations of interleukin(IL)-1ß and tumor necrosis factor(TNF)-α in the left L3-L5 spinal dorsal horn and hippocampal CA1 area were detected by ELISA, the expressions of Iba-1 in the spinal dorsal horn and hippo-campal CA1 area were detected by immunofluorescence, and the expression of BDNF in left hippocampal CA1 area was detected by Western blot. RESULTS: The HE staining results of the hippocampal CA1 area showed reduced number of neurons, unclear cell contour and boundary between nucleus and cytoplasm, and nuclear pyknosis in the model group, which was relatively milder in the EA group. Compared with the blank group, MWT and weight-bearing capacity of rats' left hind limbs, and expression of BDNF protein in hippocampal CA1 area were significantly decreased (P<0.01), while the contents of IL-1ß and TNF-α, the expression of Iba-1 in spinal dorsal horn and hippocampal CA1 area were significantly increased (P<0.01) in the model group. In comparison with the model group, MWT and weight-bearing capacity of rats' left hind limbs, and protein expression of BDNF in hippocampal CA1 area were significantly increased (P<0.01), while the contents of IL-1ß and TNF-α, and the expression of Iba-1 protein in spinal dorsal horn and hippocampal CA1 area were significantly decreased after EA intervention(P<0.01). CONCLUSION: EA at GB34 and EX-LE4 can alleviate the pain-related behaviors of KOA rats. The mechanism might be related to the inhibition of inflammatory reaction mediated by microglia in spinal dorsal horn and hippocampus, and the up-regulation of BDNF expression in hippocampus.

Epidemiological Characteristics and Influencing Factors of Myopia Among Primary School Students in Southern China: A Longitudinal Study.

Objectives: To study the epidemiological characteristics and influencing factors of myopia to provide a scientific basis for the prevention and control of myopia. Methods: 7,597 students studying in grades 1-3 were followed up. Eye examinations and questionnaire surveys were conducted annually from 2019 to 2021. The influencing factors of myopia were analyzed by logistic regression model. Results: The prevalence of myopia among students in grades 1-3 in 2019 was 23.4%, which increased to 41.9% and 51.9% after the 1-and 2-year follow-up, respectively. The incidence of myopia and change in the spherical equivalent refraction (SER) were higher in 2020 than in 2021. The 2-year cumulative incidences of myopia were 2.5%, 10.1%, 15.5%, 36.3%, and 54.1% in students with a baseline SER >+1.50D, +1.00D to +1.50D, +0.50D to +1.00D, 0.00D to +0.50D, and -0.50D to 0.00D, respectively. Outdoor activities, sex, age, baseline SER, parental myopia, sleep time, and digital device exposure were associated with myopia. Conclusion: The prevalence of myopia demonstrated a rapid increase; thus, healthy habits and outdoor activities should be promoted for the prevention and control of myopia.

Public awareness, specific knowledge, and worry about mpox (monkeypox): A preliminary community-based study in Shenzhen, China.

Background: The mpox (monkeypox) outbreak has been declared to be a public health emergency of international concern by the Director-General of World Health Organization in July 2022. However, evidence regarding the awareness, knowledge, and worry about mpox in the general population remains scant. Methods: A community-based survey targeting community residents was preliminarily conducted in Shenzhen, China in August 2022 by using a convenience sampling method. Information on mpox-related awareness, knowledge, and worry was collected from each participant. Binary logistic regression analyses with the stepwise procedure were applied to explore the factors associated with awareness, knowledge, and worry about mpox. Results: A total of 1028 community residents were included in the analysis (mean age: 34.70 years). Among these participants, 77.9% had ever heard of mpox, and 65.3% were aware of the global outbreak of mpox. However, only about half of them had a high level of knowledge regarding mpox (56.5%) and related symptoms (49.7%). More than one-third of them (37.1%) expressed a high level of worry about mpox. Having high knowledge levels of mpox and related symptoms were positively associated with a high level of worry (OR: 1.79, 95%CI: 1.22~2.63 for a single high knowledge level; OR: 1.98, 95%CI: 1.47~2.66 for both high knowledge levels). Conclusions: This study identified the gaps in public awareness and specific knowledge of mpox in Chinese people, providing scientific evidence for the prevention and control network of mpox at the community level. Targeted health education programs are of urgent need, which should be implemented along with psychological interventions to release public worry if necessary.

Research trends and hotspots in the relationship between outdoor activities and myopia: A bibliometric analysis based on the web of science database from 2006 to 2021.

Objectives: This study aimed to explore the current status, hotspots, and emerging research trends regarding the relationship between outdoor activities and myopia. Methods: Publications on the relationship between outdoor activities and myopia from 2006 to 2021 were collected from the Web of Science Core Collection database. CiteSpace (version 6.1.R2) was used to performed a bibliometric analysis, and R software (version 4.1.0) was used to visualize the trends and hot map of publications. Results: A total of 640 publications were collected and analyzed in the present study. China was the major contributor (n = 204), followed by the United States of America (n = 181) and Australia (n = 137). The United States of America had the most extensive foreign cooperation (centrality = 0.25), followed by Australia (centrality = 0.20). The National University of Singapore contributed the largest number of publications (n = 48), followed by Sun Yat-Sen University (n = 41) and the Australian National University (n = 41). Among institutions, Cardiff University in the United Kingdom had the most extensive foreign cooperation (centrality = 0.12), followed by the National University of Singapore (centrality = 0.11). Saw S from Singapore had the largest number of publications (n = 39), followed by Morgan I from Australia (n = 27) and Jonas J from Germany (n = 23). Investigative ophthalmology & visual science is the most important journal to study the relationship between outdoor activities and myopia. "Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050" published by Holden BA was the most cited paper in this field with 177 citations. Co-occurrence and burst analyses of keywords showed that research trends and hotspots in this field focused mainly on "risk," "prevention" and "school". Conclusions: The influence of outdoor activities on myopia remains a concern. In the future, deeper cooperation between countries or institutions is required to explore the effects of outdoor activities on myopia. Outdoor activities for the prevention of myopia and reduction of the risk of myopia among school students may be the focus of future research.

The accuracy of the axial length and axial length/corneal radius ratio for myopia assessment among Chinese children.

Objectives: The aim of this study was to assess the association between axial length/corneal radius ratio (AL/CR ratio), AL, and refractive status and evaluate the accuracy of AL and AL/CR ratio for myopia assessment among Chinese children. Methods: A diagnostic trial was conducted in Shenzhen Eye Hospital from June 2020 to December 2020. Cycloplegic refraction and demographic characteristic survey were carried out, and AL and CR were measured. The Pearson correlation analysis between AL, AL/CR ratio, and spherical equivalent (SE) was carried out. The sensitivity, specificity, Youden index, positive predictive value, and negative predictive value of the AL/CR ratio and AL for myopia assessment were analyzed using cycloplegic refraction as the gold standard by drawing receiver operating characteristic (ROC) curves. Results: A total of 300 children aged 8-18 years participated in this study. The Pearson correlation coefficient between AL and SE was -0.667 (P < 0.05) and -0.754 (P < 0.05) between AL/CR ratio and SE. There were significant differences in SE, AL, and AL/CR ratio among different age groups (p < 0.05). SE decreased by 1.185 diopter (D) for every 1 mm increase in AL and decreased by 0.667 D for every 0.1 increase in the AL/CR ratio. Taking cycloplegic refraction SE ≤ -0.50 D as the gold standard for the diagnosis of myopia, the area under the ROC curve of AL for myopia assessment was 0.836 (95% confidence interval [CI]: 0.767-0.906), with specificity, sensitivity, and Youden index of 0.833, 0.767, and 0.600, respectively. The area under the ROC curve of AL/CR ratio for myopia assessment was 0.937 (95% CI: 0.878-0.996), with specificity, sensitivity, Youden index, positive predictive value, and negative predictive value of 0.703, 0.913, 0.622, 0.956, and 0.771, respectively. The area under the ROC curve of the combination of AL/CR ratio and parental myopia for myopia assessment was 0.976 (95% CI: 0.957-0.996). Conclusion: The correlation between SE and AL/CR ratio was stronger than that between SE and AL in children. The AL/CR ratio may be an alternative indicator for myopia assessment in children, and the combination of demographic factors and AL/CR ratio can improve the accuracy of myopia assessment.

Association of COVID-19 Lockdown With Gestational Diabetes Mellitus.

Importance: The ongoing pandemic of COVID-19 is still affecting our life, but the effects of lockdown measures on gestational diabetes mellitus (GDM) in pregnant women remain unclear. Aim: To investigate the association between COVID-19 lockdown and GDM. Subjects and Methods: Medical records of 140844 pregnant women during 2015-2020 were extracted from 5 hospitals in Guangdong Province, China. Pregnant women who underwent the COVID-19 Level I lockdown (1/23 - 2/24/2020) during pregnancy were defined as the exposed group (N=20472) and pregnant women who underwent the same calendar months during 2015-2019 (1/23 - 2/24) were defined as the unexposed group (N=120372). Subgroup analyses were used to explore the potential susceptible exposure window of COVID-19 lockdown on GDM. Cumulative exposure is quantitatively estimated by assigning different weights to response periods with different exposure intensities. A logistic regression model was used to estimate the association between COVID-19 lockdown exposure and GDM. Results: The rates of GDM in the exposed and unexposed groups were 15.2% and 12.4%, respectively. The overall analyses showed positive associations (odds ratio, OR=1.22, 95%CI: 1.17, 1.27) between lockdown exposure and GDM risk in all pregnant women. More pronounced associations were found in women who underwent the COVID-19 lockdown in their first four months of pregnancy, and the adjusted OR values ranged from 1.24 (95%CI: 1.10, 1.39) in women with 5-8 gestational weeks (GWs) to 1.35 (95%CI: 1.20, 1.52) with < 5 GWs. In addition, we found a positive exposure-response association of cumulative lockdown exposure with the risk of GDM. Conclusions: The COVID-19 lockdown was associated with an increased risk of GDM, and the first four months of pregnancy may be the window for sensitive exposure.

Associations of COVID-19 lockdown with gestational length and preterm birth in China.

BACKGROUND: The effects of COVID-19 lockdown measures on maternal and fetal health remain unclear. We examined the associations of COVID-19 lockdown with gestational length and preterm birth (PTB) in a Chinese population. METHODS: We obtained medical records of 595,396 singleton live infants born between 2015 and 2020 in 5 cities in Guangdong Province, South China. The exposed group (N = 101,900) included women who experienced the COVID-19 Level I lockdown (1/23-2/24/2020) during pregnancy, while the unexposed group (N = 493,496) included women who were pregnant during the same calendar months in 2015-2019. Cumulative exposure was calculated based on days exposed to different levels of emergency responses with different weighting. Generalized linear regression models were applied to estimate the associations of lockdown exposure with gestational length and risk of PTB (< 37 weeks). RESULTS: The exposed group had a shorter mean gestational length than the unexposed group (38.66 vs 38.74 weeks: adjusted ß = - 0.06 week [95%CI, - 0.07, - 0.05 week]). The exposed group also had a higher risk of PTB (5.7% vs 5.3%; adjusted OR = 1.08 [95%CI, 1.05, 1.11]). These associations seemed to be stronger when exposure occurred before or during the 23rd gestational week (GW) than during or after the 24th GW. Similarly, higher cumulative lockdown exposure was associated with a shorter gestational length and a higher risk of PTB. CONCLUSIONS: The COVID-19 lockdown measures were associated with a slightly shorter gestational length and a moderately higher risk of PTB. Early and middle pregnancy periods may be a more susceptible exposure window.

Associations Between Air Pollution Exposure and Daily Pediatric Outpatient Visits for Dry Eye Disease: A Time-Series Study in Shenzhen, China.

Objectives: This study aimed to investigate the associations between air pollution exposure and pediatric outpatient visits for dry eye disease (DED) in Shenzhen, China. Methods: Generalized additive models were utilized to explore the acute effects of air pollution exposure on pediatric outpatient visits for DED. Results: Single-day lag exposures to NO2, O3, PM2.5, and PM10 were associated with DED outpatient visits at lag days 0, 6, 4 and 2. Relative risks (RRs) for DED given a 10-µg/m3 increase in NO2, O3, PM2.5, and PM10 concentrations were 1.062[95% confidence interval (CI) 1.003, 1.123], 1.015(95% CI 1.001, 1.031), 1.052(95% CI 1.001, 1.115), and 1.038 (95% CI 1.002, 1.076), respectively. RR for DED given a 10-µg/m3 increase in NO2 over cumulative lag days 0-1 was 1.075 (95% CI 1.009, 1.147), and RR for DED given a 10-µg/m3 increase in PM10 over cumulative lag days 0-4 was 1.051 (95% CI 1.003, 1.102). Conclusion: The observed associations between air pollution and outpatient visits for DED may provide evidence for policy makers to consider implementing measures to reduce the risk of DED owing to air pollution in China.

The Mediating Role of Placental Weight Change in the Association Between Prenatal Exposure to Thallium and Birth Weight: A Prospective Birth Cohort Study.

Background: Previous studies have demonstrated the embryotoxicity and fetotoxicity of thallium (Tl). However, the effects of prenatal exposure to Tl on birth weight and placental weight and the mediating role of placental weight in the association of Tl with birth weight remain unclear. Methods: We recruited 2,748 participants from the ongoing Prenatal Environment and Offspring Health Cohort (PEOH Cohort) study, which was initiated in 2016 in Guangzhou, China. The Tl concentrations in maternal urine samples collected during the first and third trimester were determined by inductively coupled plasma mass spectrometry. Birth weight and placental weight were extracted from maternal medical records. Results: Pregnant women exposed to the highest tertile of Tl in the first trimester (ß = -42.7 g, 95% CI: -82.3, -3.1 g) and third trimester (ß = -50.6 g, 95% CI: -99.0, -2.3 g) had babies with lower birth weights than those exposed to the lowest tertile. We also found significant negative associations of exposure to Tl concentrations in the first and third trimester with placental weight. Mediation analyses showed that 50.3% (95% CI: 15.9, 79.2%) and 33.5% (95% CI: 1.3, 80.3%) of the effects of Tl exposure in the first and third trimester on birth weight were mediated by decreased placental weight. Conclusion: Our results suggest that prenatal exposure to Tl is negatively associated with birth weight and that this association may be mediated by decreased placental weight.

Parental psychological distress and attitudes towards COVID-19 vaccination: A cross-sectional survey in Shenzhen, China.

BACKGROUND: Parental attitudes towards the vaccines play a key role in the success of the herd immunity for the COVID-19. Psychological health seems to be a controversial determinant of vaccine hesitancy and remains to be investigated. This study attempted to measure parental psychological distress, attitudes towards the COVID-19 vaccine, and to explore the potential associations. METHODS: An online survey using convenience sampling method was conducted among parents within the school public health network of Shenzhen. Demographic information and attitudes towards COVID-19 vaccination were collected. The Patient Health Questionnaire (PHQ-4) was applied to measure psychological distress. RESULTS: Overall, 4,748 parents were included (average age: 40.28, standard deviation: 5.08). More than one fifth of them demonstrated psychological distress, in which only 3.3% were moderate to severe symptom. The proportions of COVID-19 vaccine hesitancy for themselves, their spouses, and their children were 25.2%, 26.1%, and 27.3%, respectively. Parents with psychological distress were more likely to suffer vaccine hesitancy for themselves (OR: 1.277, 95%CI: 1.091~1.494), for their spouses (OR:1.276, 95%CI: 1.088~1.496) and children (OR:1.274, 95%CI: 1.092~1.486). These associations tended to be more significant among parents with mild or severe psychological distress. LIMITATION: Non-random sampling limited the generalization of our findings to all parents. CONCLUSION: Parents had a low level of psychological distress but relatively high willingness of COVID-19 vaccination when there was no local epidemic but persistent risk of imported cases. Targeted health education and intervention strategies should be provided to people with vaccine hesitancy, especially for those who are susceptible to psychological distress.

Reduction of air pollutants and associated mortality during and after the COVID-19 lockdown in China: Impacts and implications.

Although strict lockdown measurements implemented during the COVID-19 pandemic have dramatically reduced the anthropogenic-based emissions, changes in air quality and its health impacts remain unclear in China. We comprehensively described air pollution during and after the lockdown periods in 2020 compared with 2018-2019, and estimated the mortality burden indicated by the number of deaths and years of life lost (YLL) related to the air pollution changes. The mean air quality index (AQI), PM10, PM2.5, NO2, SO2 and CO concentrations during the lockdown across China declined by 18.2 (21.2%), 27.0 µg/m3 (28.9%), 10.5 µg/m3 (18.3%), 8.4 µg/m3 (44.2%), 13.1 µg/m3 (38.8%), and 0.3 mg/m3 (27.3%) respectively, when compared to the same periods during 2018-2019. We observed an increase in O3 concentration during the lockdown by 5.5 µg/m3 (10.4%), and a slight decrease after the lockdown by 3.4 µg/m3 (4.4%). As a result, there were 51.3 (95%CI: 32.2, 70.1) thousand fewer premature deaths (16.2 thousand during and 35.1 thousand after the lockdown), and 1066.8 (95%CI: 668.7, 1456.8) thousand fewer YLLs (343.3 thousand during and 723.5 thousand after the lockdown) than these in 2018-2019. Our findings suggest that the COVID-19 lockdown has caused substantial decreases in air pollutants except for O3, and that substantial human health benefits can be achieved when strict control measures for air pollution are taken to reduce emissions from vehicles and industries. Stricter tailored policy solutions of air pollution are urgently needed in China and other countries, especially in well-developed industrial regions, such as upgrading industry structure and promoting green transportation.

The mediation effect of placental weight change in the association between prenatal exposure to selenium and birth weight: Evidence from a prospective birth cohort study in China.

Selenium (Se) is an essential element and also toxic at an excessive level for human body. However, few studies have investigated adverse effects of Se exposure on birth weight and placental weight. METHODS: All participants were selected from the Prenatal Environment and Offspring Health cohort conducted in 2016 in Guangzhou, China. Se in each participant was measured by inductively coupled plasma mass spectrometry in their urine samples. The urinary Se concentrations were corrected by creatinine and transformed by natural logarithm (ln-Se). Multiple-linear regression models were applied to estimate the associations among Se exposure levels, placenta weight, and birth weight. RESULTS: A total of 2758 mother-newborn pairs were included in this study. Each interquartile range (0.53 µg/g creatinine) increment in urine ln-Se concentration during the first trimester was associated with a mean 21.7 g (95% CI = -41.3g to -2.1g) decrease in birth weight and 3.6g (95% CI = -6.3g to -0.9g) decrease in placental weight. Compared with the lowest quartile (Q1) of ln-Se concentrations during the first trimester, significantly lower birth weight was found in the highest quartile (Q4) (ß = -45.7g; 95% CI = -90.7g to -0.7g). Similar dose-response associations with birthweight and placental weight were found for Se exposure during the third trimester. Mediation analyses showed that 44.2% and 18.2% of the effects of Se exposure in first and third trimester on birth weight were mediated by decreased placental weight, respectively. CONCLUSION: Maternal Se exposure during pregnancy was negatively associated with birth weight, the reduction of placental weight may partially mediate the association of prenatal Se exposure with birth weight.

[Effects of electroacupuncture on pain behavior and pain-related factors in spinal cord dorsal horn and dorsal root ganglia of rats with knee osteoarthritis].

OBJECTIVE: To observe the effect of electroacupuncture(EA) on the pain behavior and prostaglandin E2 (PGE2), calcitonin gene-related peptide (CGRP) and substance P (SP) in the spinal cord dorsal horn and dorsal root ganglia (DRG) of rats with knee osteoarthritis (KOA), so as to explore the mechanisms of EA underlying improvement of chronic pain in KOA rats. METHODS: Thirty-two female SD rats were randomly divided into blank group, control group, model group and EA group, with 8 rats in each group. Rats in the control group were injected with 50 µL of 0.9% sodium chloride solution into the left knee joint cavity, and rats in the model and EA groups were injected with 50 µL of Monosodium iodoacetate in the left knee joint. EA(2 Hz/100 Hz, ＜2 mA) was applied to left "Yanglingquan"(GB34) and "Neixiyan" (EX-LE4) for 15 min, once daily, 5 days a course with a total of 2 courses. Paw withdrawal latency (PWL) and mechanical pain threshold (PWT) were tested by Plantar Test and Von Frey, separately. After the last pain test, the contents of PGE2, CGRP and SP in the left lumbar (L) 3-L5 DRG and L3-L5 spinal dorsal horn were detected by ELISA. RESULTS: Compared with the blank group, the PWL and PWT of the rats in the model group were significantly decreased (P<0.01), and the contents of PGE2, CGRP and SP in the DRG and spinal dorsal horn were significantly increased (P<0.01, P<0.05). There were no statistically significant differences in PWL, PWT, contents of PGE2, CGRP and SP in DRG and spinal dorsal horn between the blank group and the control group (P>0.05). Compared with the model group, the PWL and PWT of rats in the EA group were significantly increased (P<0.01), and the contents of PGE2, CGRP and SP in the DRG and spinal dorsal horn were significantly decreased (P<0.01, P<0.05). CONCLUSION: EA of GB34 and EX-LE4 can reduce the levels of pain-related factors PGE2, CGRP and SP in the DRG and spinal dorsal horn, thereby relieving spinal hyperalgesia in rats with KOA.

[Analysis on the pollution characteristics and influence factors of PM_(2. 5) in Shenzhen City in 2016].

OBJECTIVE: To explore the pollution characteristics and possible influence factors of PM_(2. 5)in Shenzhen in 2016. METHODS: The dynamic characters of PM_(2. 5)mass concentration were analyzed using air quality monitoring and meteorology observation data. The correlations between PM_(2. 5)and other affecting factors, e. g. gas pollutions and meteorology factors, were discussed. A multiple linear regression model was built to reveal the impacts of those factors on PM_(2. 5)concentrations in Shenzhen City using the air quality monitoring and meteorology observation data. RESULTS: The mass concentration of PM_(2. 5)was(27. 02±13. 88)µg/m~3, and the ratios of PM_(2. 5)/PM_(10)was(0. 62±0. 08)in Shenzhen City. Significant positive correlations existed between PM_(2. 5)concentration and main airpollutants(NO_2, SO_2, CO and O_3)(P<0. 05). A significant negative correlation existed between PM_(2. 5) concentration and temperature, relative humidity(P<0. 05), and also a significant positive correlation between atmospheric pressure and PM_(2. 5)concentration. The multiple linear regression showed that air pollutants(NO_2, SO_2, CO, and O_3)and atmospheric pressure could explain 86. 7% of the variations of PM_(2. 5)concentration. The standard regression coefficient of CO in the model was the highest(0. 439). CONCLUSION: PM_(2. 5)pollution was relatively light in Shenzhen City, and PM_(2. 5)was the main component of inhalable particulate matter. Atmospheric pressure and other pollutants in the atmosphere were the main influencing factors of PM_(2. 5)concentration, and CO was the major contributor to PM_(2. 5)concentration rising in Shenzhen City.

[Temporal and spatial distribution of air pollution in Shenzhen City during 2014-2016].

OBJECTIVE: To investigate spatial-temporal distribution characteristics of air quality indexes( AQI) in Shenzhen City and provide scientific basis for control of air pollution. METHODS: The monitoring data of AQI collected at the 19 monitoring posts in Shenzhen City from 2014 to 2016 were pooled and analyzed, and daily, seasonal and annual means of AQI at each monitoring post were forked out. The theory of spatial autocorrelation analysis was adopted in analyzing strength of the spatial autocorrelation and spatial clustering patterns of AQI. RESULTS: The median of AQI of Shenzhen City was50. 0, and the air quality level of Shenzhen City was level 2. PM_(2. 5) was the primary air pollutant in 2014, and O_3 was the primary air pollutant in 2015 and 2016 respectively. From the time distribution, the air quality in Shenzhen City was the worst in the winter but the best in the summer, and the air quality in night was worse than the day. Spatial autocorrelation analysis showed that there was positive spatial autocorrelation of AQI in Shenzhen. The global moran's I of AQI was 0. 167( Z = 2. 000, P < 0. 05), and the greary coefficient was 0. 801( Z = 1. 711, P < 0. 05). The local moran's I of AQI was 1. 027( P < 0. 05) in Guangming New District. The moran scatter plot of AQI in Guangming New District was in the first quadrant, and appeared to be in a high-high clustering pattern. The moran scatter plot of AQI in Yantian District was in the third quadrant, and appeared to be in a low-low clustering pattern. CONCLUSION: The air quality of Shenzhen City was better. PM_(2. 5) and O_3 were the primary air pollutant. It is necessary to emphasize and strengthen the prevention and control of air pollution in Winter, especially in several administrative districts of the northwest of Shenzhen City.

Diethyl 4,4'-(3,6-dioxaoctane-1,8-diyl-dioxy)dibenzoate.

The title compound, C(24)H(30)O(8), was obtained by reaction of ethyl 4-hy-droxy-benzoate with 1,2-dichloro-ethane. The mol-ecule occupies a crystallographic inversion center, with its central ethyl-ene bridge in an anti conformation. The other ethyl-ene bridge has a gauche conformation, with the corresponding O-C-C-O torsion angle being 74.2 (1)°. The benzene rings are almost coplanar with the adjacent eth-oxy-carbonyl groups, with an r.m.s. deviation of 0.078 Å.