The close environments of accreting massive black holes are shaped by radiative feedback.

The majority of the accreting supermassive black holes in the Universe are obscured by large columns of gas and dust. The location and evolution of this obscuring material have been the subject of intense research in the past decades, and are still debated. A decrease in the covering factor of the circumnuclear material with increasing accretion rates has been found by studies across the electromagnetic spectrum. The origin of this trend may be driven by the increase in the inner radius of the obscuring material with incident luminosity, which arises from the sublimation of dust; by the gravitational potential of the black hole; by radiative feedback; or by the interplay between outflows and inflows. However, the lack of a large, unbiased and complete sample of accreting black holes, with reliable information on gas column density, luminosity and mass, has left the main physical mechanism that regulates obscuration unclear. Here we report a systematic multi-wavelength survey of hard-X-ray-selected black holes that reveals that radiative feedback on dusty gas is the main physical mechanism that regulates the distribution of the circumnuclear material. Our results imply that the bulk of the obscuring dust and gas is located within a few to tens of parsecs of the accreting supermassive black hole (within the sphere of influence of the black hole), and that it can be swept away even at low radiative output rates. The main physical driver of the differences between obscured and unobscured accreting black holes is therefore their mass-normalized accretion rate.

Robust lockwire segmentation with multiscale boundary-driven regional stability.

Lockwire segmentation plays a vital role in ensuring mechanical safety in industrial fields. Aiming at the missed detection problem encountered in blurred and low-contrast situations, we propose a robust lockwire segmentation method based on multiscale boundary-driven regional stability. We first design a novel multiscale boundary-driven stability criterion to generate a blur-robustness stability map. Then, the curvilinear structure enhancement metric and linearity measurement function are defined to compute the likeliness of stable regions to belong to lockwires. Finally, the closed boundaries of lockwires are determined to achieve accurate segmentation. Experimental results demonstrate that our proposed method outperforms state-of-the-art object segmentation methods.

Pregnancy complications and risk of uterine rupture among women with singleton pregnancies in China.

BACKGROUND: The goal of this study was to investigate whether pregnancy complications are associated with an increased risk of uterine rupture (UR) and how that risk changes with gestational age. METHODS: We obtained all data from China's National Maternal Near Miss Surveillance System (NMNMSS) between 2012 and 2018. Poisson regression analysis was used to assess the risk of UR with pregnancy complications (preeclampsia, gestational diabetes mellitus, placental abruption, placenta previa and placenta percreta) among 9,454,239 pregnant women. Furthermore, we analysed the risks of UR with pregnancy complications in different gestational age groups. RESULTS: The risk of UR was increased 2.0-fold (1.2-fold to 2.7-fold) in women with pregnancy complications (except for preeclampsia). These associations also persisted in women without a previous caesarean delivery. Moreover, an increased risk of UR before term birth was observed among women with gestational diabetes mellitus, placental abruption and placenta percreta. The risk of UR was slightly higher in women with gestational diabetes mellitus who had a large for gestational age (LGA) foetus, especially at 32 to 36 weeks gestation. CONCLUSIONS: The risk of UR is associated with gestational diabetes mellitus, placental abruption, placenta previa and placenta percreta, but varies in different gestational ages.

Temporal trends and adverse perinatal outcomes of twin pregnancies at differing gestational ages: an observational study from China between 2012-2020.

BACKGROUND: With the development of assisted reproductive technology, the twinning rate in China has been increasing. However, little is known about twinning from 2014 onwards. In addition, previous studies analysing optimal gestational times have rarely considered maternal health conditions. Therefore, whether maternal health conditions affect the optimal gestational time remains unclear. METHODS: Data of women delivered between January 2012 and December 2020 were collected through China's National Maternal Near Miss Surveillance System. Interrupted time series analysis was used to determine the rates of twinning, stillbirth, smaller than gestational age (SGA), and low Apgar scores (< 4) among twins in China. To estimate the risk of each adverse perinatal outcome for separate gestational weeks, a multivariate generalised linear model was used. Infants born at 37 weeks of gestational age or foetuses staying in utero were used as reference separately. The analyses were adjusted for the sampling distribution of the population and the cluster effect at the hospital and individual levels were considered. RESULTS: There were 442,268 infants enrolled in this study, and the adjusted rates for twinning, stillbirth, SGA, and low Apgar scores were 3.10%, 1.75%, 7.70%, and 0.79%, respectively. From 2012 to 2020, the twinning rate showed an increasing trend. Adverse perinatal outcomes, including stillbirth, SGA, and low Apgar scores showed a decreasing trend. A gestational age between 34 and 36 weeks decreased most for rate of stillbirth (average changing rate -9.72%, 95% confidence interval [CI] -11.41% to -8.00%); and a gestational age of between 37 and 38 weeks decreased most for rates of SGA (average changing rate -4.64%, 95% CI -5.42% to -3.85%) and low Apgar scores (average changing rate -17.61%, 95% CI -21.73% to -13.26%). No significant difference in changes in twinning rate or changes of each perinatal outcome was observed during periods of different fertility policies. Infants born at 37 weeks of gestation had a decreased risk of stillbirth, SGA, and low Apgar scores. Maternal antepartum or medical complications increased the risk of SGA and low Apgar scores in different gestational weeks. CONCLUSION: China's twinning rate showed an increasing trend, while adverse perinatal outcomes decreased from 2012 to 2020. Fertility policy changes have had little effect on the twinning rate or the rate of adverse perinatal outcomes such as stillbirth, SGA, or low Apgar scores. The optimal gestational age for twins was 37 weeks. Women pregnant with twins and with antepartum or medical complications should be cautious due to an increased risk of SGA and low Apgar scores.

Characteristics and fetal outcomes of pregnant women with hypertensive disorders in China: a 9-year national hospital-based cohort study.

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are a growing concern and a challenge for maternity care providers as the prevalence of hypertension continues to increase. However, optimal management of HDP is unclear. Therefore, we aimed to explore the differences in adverse fetal outcomes among women with different subtypes of HDP and different blood pressure (BP) levels, to provide evidence-based management of HDP. METHODS: We obtained data from China's National Maternal Near-Miss Surveillance System from 2012 to 2020. Associations between BP management and adverse fetal outcomes, stratified by the four subtypes of HDP, were assessed using logistic regression analysis with a robust variance estimator. RESULTS: For the period, a total of 393,353 pregnant women with HDP were included in the study; 8.51% had chronic hypertension, 2.27% had superimposed preeclampsia, 50.17% had preeclampsia or eclampsia, and 39.04% had gestational hypertension. The BP levels at delivery admission were mostly (61.14%) of non-severe stage 2 (systolic BP 140-159 mm Hg and/or diastolic BP 90-109 mm Hg) hypertension by American Heart Association classification. A high rate of adverse fetal outcomes was observed among women with HDP, especially among those aged < 20 or > 35 y or those diagnosed with superimposed preeclampsia. Compared with those with normal BP levels at delivery admission, we found an upward curve with increased risk among pregnant women with more severe BP levels, including the risk of preterm birth and small for gestational age (SGA) fetus. The odds ratios (ORs) of stillbirth, neonatal death, and low Apgar scores associated with severe stage 2 hypertension increased significantly. In addition, the association between BP at admission and fetal outcomes differed among women with varying HDP subtypes. Pregnant women with preeclampsia or eclampsia had an increased risk for preterm birth (adjusted OR [aOR], 1.33 [95% confidence interval {CI}, 1.07 ~ 1.65]) and SGA (aOR, 1.37 [95% CI, 1.10 ~ 1.71]) even when the admission BP was at stage 1 level. CONCLUSION: Greater attention should be paid to cases involving preeclampsia superimposed on chronic hypertension and pregnant women aged < 20 or > 35 y to mitigate the burden of adverse fetal outcomes caused by HDP.

The incidence, risk factors and maternal and foetal outcomes of uterine rupture during different birth policy periods: an observational study in China.

BACKGROUND: Currently, there are no studies on changes in the incidence of uterine rupture or maternal and foetal outcomes in women with uterine rupture during different birth policy periods in China. Moreover, the results of association studies of maternal age, parity and previous caesarean section number with the risk of maternal and foetal outcomes in women with uterine rupture have not been consistent. This research aims to conduct and discuss the above two aspects. METHODS: We included singleton pregnant women with no maternal complications other than uterine rupture from January 2012 to June 2019 in China's National Maternal Near Miss Surveillance System. The data in this study did not differentiate between complete and partial uterine rupture and uterine dehiscence. Through Poisson regression analysis with a robust variance estimator, we compared the incidences of uterine rupture and maternal and foetal outcomes in women with uterine rupture during different birth policy periods in China and determined the relationship between maternal age, parity or previous caesarean section number and uterine rupture or maternal and foetal outcomes in women with uterine rupture. RESULTS: This study included 8,637,723 pregnant women. The total incidences of uterine rupture were 0.13% (12,934) overall, 0.05% during the one-child policy, 0.12% during the partial two-child policy (aRR = 1.96; 95% CI: 1.53-2.52) and 0.22% (aRR = 2.89; 95% CI: 1.94 4.29) during the universal two-child policy. The maternal near miss and stillbirth rates in women with uterine rupture were respectively 2.35% (aRR = 17.90; 95% CI: 11.81-27.13) and 2.12% (aRR = 4.10; 95% CI: 3.19 5.26) overall, 5.46 and 8.18% during the first policy, 1.72% (aRR = 0.60; 95% CI: 0.32-1.17) and 2.02% (aRR = 0.57; 95% CI: 0.37-0.83) during the second policy, and 1.99% (aRR = 0.90; 95% CI: 0.52-1.53) and 1.04% (aRR = 0.36; 95% CI: 0.24-0.54) during the third policy. The risk of uterine rupture increased with parity and previous caesarean section number. CONCLUSION: The uterine rupture rate in China continues to increase among different birth policy periods, and the risk of maternal near miss among women with uterine rupture has not significantly improved. The Chinese government, obstetricians, and scholars should work together to reverse the rising rate of uterine rupture and improve the pregnancy outcomes in women with uterine rupture.

Apgar score and neonatal mortality in China: an observational study from a national surveillance system.

BACKGROUND: To examine the association between the Apgar score and neonatal mortality over gestational age in China and to explore whether this association changed when Apgar scores were combined at 1 and 5 min. METHODS: Data for all singleton live births collected from 438 hospitals between 2012 and 2016 were used in this study. Poisson regression with a robust variance estimator adjusted for a complete set of confounders was used to describe the strength of the association between the Apgar score and neonatal mortality. RESULTS: The relative risks of neonatal death-associated intermediate Apgar score at 5 min peaked at 39-40 weeks of gestation and subsequently decreased if the gestational age increased to 42 weeks or above, in contrast to the low Apgar score. Among both preterm and term new-borns with Apgar scores at 5 min, new-borns that were not small for gestational age had a lower mortality rate than those that were small for gestational age. The association between Apgar score and the neonatal mortality was even stronger when scores at 1 and 5 min were combined. CONCLUSIONS: Apgar score is not only meaningful for preterm new-borns but also useful for term new-borns, especially term new-borns that are not small for gestational age. Once the baby's Apgar score worsens, timely intervention is needed. There is still a gap between China and high-income countries in terms of sustained treatment of new-borns with low Apgar scores.

Influence of uric acid on the correlation between waist circumference and triglyceride glucose index: an analysis from CHARLS.

BACKGROUND: Waist circumference (WC) and uric acid (UA) are significantly related. Still, their temporal sequence and how the sequence works on future risk of triglyceride glucose (TyG) are unknown, especially in the Chinese population. METHODS: Cross-lagged panel model was used to analyze the reciprocal, longitudinal relationships among a set of interrelated variables. The mediation model was constructed to test the effect of the relationship between WC and UA on TyG. RESULTS: A total of 5727 subjects were enrolled in our study population, of which 53.5% were women, and the mean age was 59.0 (standard deviation, 8.62) years. After adjusting for traditional confounding factors, the results showed that a higher level of baseline WC was significantly associated with a higher level of follow-up UA (ß = 0.003, P = 0.031) and follow-up TyG (ß = 0.003, P < 0.001);. Simultaneously, there was no statistical association between the level of baseline UA and the level of follow-up WC (ß = - 0.009, P = 0.951). The mediation effects of UA on WC-TyG were estimated to be 18.1% in adults, and 36.2% in women. CONCLUSIONS: The current study demonstrated that higher baseline level of WC probably preceded UA' level in general population. In addition, UA mediated the relationship of WC to TyG, especially in females. And the possible mechanism would require further clarification.

Potential impacts of the 2017 American College of Cardiology/American Heart Association high blood pressure guideline on Chinese adults and how to address them.

BACKGROUND: The current analysis was performed to estimate the percentage and number of Chinese adults with hypertension and the percentage and number of Chinese adults recommended to receive pharmacological antihypertensive treatment according to the 2017 American College of Cardiology/American Heart Association (ACC/AHA) guideline compared with the same parameters according to the 2010 Chinese guideline. METHODS: We used 2011 data from the China Health and Nutrition Survey (CHNS). A total of 12,499 Chinese adults aged ≥18 years with complete blood pressure (BP) values were selected for the present analysis. RESULTS: The crude prevalence rates (95% CI) of hypertension according to the definitions from the 2017 ACC/AHA guideline and the 2010 Chinese guideline were 58.0% (57.2 to 58.9%) and 25.4% (24.7 to 26.2%), respectively. Moreover, the percentage of the participants recommended to take antihypertensive medications were 31.5 and 28.8%, respectively. Among adults who took antihypertensive medications, 88.8% had above-goal BP levels compared to 53.3%. Overall, 613.3 million Chinese adults (aged ≥18 years) met the criteria for hypertension according to the 2017 ACC/AHA guideline, and 267.7 million met the criteria according to 2010 Chinese guideline. An additional 28.4 million (2.7%) Chinese adults were recommended to take antihypertensive medication. CONCLUSIONS: The present analysis revealed that the 2017 ACC/AHA hypertension guideline will result in a substantial increase in the percentage and number of Chinese adults defined as having hypertension and a small increase in the percentage of adults who are recommended to take antihypertensive medications compared to the same parameters based on the 2010 Chinese guideline. More intensive management and antihypertensive medications use are suggested to improve the control rate of hypertension among Chinese adults.

Blood pressure predictors of stroke in rural Chinese dwellers with hypertension: a large-scale prospective cohort study.

BACKGROUND: Little was known about the different predictive power of blood pressure (BP) parameters (SBP, systolic BP; mean arterial pressure, MAP; pulse pressure, PP; and diastolic BP, DBP) and stroke incidence. This study's aim was to compare power of BP parameters predict stroke events among rural dwelling Chinese individuals with hypertension. METHOD: A total of 5097 hypertension patients (56.2% women; mean age, 56.3 ± 11.2 years) were included in the prospective cohort study with a median follow-up of 8.4 years. RESULTS: Until the end of the last follow-up, there were 501 onset strokes (310 ischemic, 186 hemorrhagic, and 5 unclassified strokes) among the 5097 participants. The results showed that hazard ratio (HR) (95% confidence interval, 95% CI) with an increment of 5 mmHg were 1.095 (1.070-1.121) for PP, 1.173 (1.139-1.208) for MAP, 1.109(1.089-1.130) for SBP, 1.143(1.104-1.185) for DBP. The SBP indicated the largest ß coefficient in the Cox proportional hazard model for all stroke except PP or MAP, and the SBP revealed slightly higher value than MAP (ßSBP = 0.435, ßMAP = 0.430, P = 0.756). CONCLUSIONS: Both PP and MAP were predictive factors for stroke. The MAP showed a stronger ability to predict stroke events than PP, and slightly inferior to SBP for hypertension patients.

Elevated blood pressure level based on 2017 ACC/AHA guideline in relation to stroke risk in rural areas of Liaoning province.

BACKGROUND: The new ACC/AHA hypertension guideline lower the definition of hypertension from 140/90 mmHg to 130/80 mmHg and eliminate the category of prehypertension thus increasing the prevalence of hypertension. A purpose of this study is to explore the applicability of the new guidelines in rural China. METHODS: In total, 3229 participants aged ≥35 years and free of stroke at baseline were followed for up to 4.8 years during 2012 to 2017 in a rural community-based prospective cohort study of Xifeng County. The hazard ratio (HR) and 95% Confidence interval (CI) of different blood pressure (BP) levels for risk of incident stroke were analyzed by multivariable Cox proportional hazard models. RESULTS: During the follow-up, 81 new strokes occurred among the 3229 participants. Compared with normal BP (Systolic BP (SBP)<120 mmHg and Diastolic BP (DBP)<80 mmHg), stage 2 hypertension (SBP ≥ 140 mmHg or DBP ≥ 90 mmHg) had approximately 2.1 greater risks for stroke (HR: 2.10, 95% CI: 1.13 to 3.91, P = 0.020). However, there was no significant association between elevated (SBP:120-129 mmHg and DBP<80 mmHg), stage1 hypertension (SBP:130-139 mmHg or DBP:80-89 mmHg) and stroke incidence (HR: 0.93, 95% CI: 0.33 to 2.61, P = 0.888; HR: 0.96, 95% CI: 0.46 to 2.02, P = 0.920, respectively). An increase of the SBP by 1-SD increases the risk for stroke by 56% (HR: 1.56, 95%CI: 1.29 to 1.88, P < 0.001). An increase of the SBP by 20 mmHg increases the risk for stroke by 51% (HR: 1.51, 95%CI: 1.27 to 1.80, P < 0.001). CONCLUSIONS: Compared with normal BP, the stage 2 hypertension based on 2017 ACC/AHA guideline significantly increases the risk of stroke incidence, but this association was not observed between elevated, stage1 hypertension and stroke incidence in Chinese rural adults.

Temporal relationship between body mass index and triglyceride-glucose index and its impact on the incident of hypertension.

BACKGROUND AND AIMS: Obesity and insulin levels can influence each other by metabolism. However, their temporal sequences and influence on hypertension are generally unknown, especially in Chinese adults. Recently, some scholars have proposed that triglycerides-glucose index (TyG) is an important indicator of insulin resistance. The study aims to describe the relationship between body mass index (BMI) and TyG index and its impact on hypertension. METHODS AND RESULTS: A total of 4081 adults (56.33% women) without antihypertensive, hypoglycemic or lipid-lowering medications were selected for the present study. Measurements of BMI and TyG index were obtained twice from 2012 to 2017. Cross-lagged panel analysis was used to describe the temporal sequences between BMI and TyG index, and the effect of their temporal relationship patterns on hypertension was explored through mediation analysis. After adjusting for confounding factors (age, sex, ethnicity et al.), the cross-lagged path coefficient from baseline BMI to follow-up TyG (ρ2 = 0.135, P < 0.001) was significantly greater than the path coefficient from baseline TyG to follow-up BMI (ρ1 = 0.043, P < 0.001), and P < 0.001 for the difference between ρ1 and ρ2. Furthermore, the sensitivity analyses between women and men revealed identical findings. In addition, TyG index mediation effect on BMI-hypertension was estimated to be 38.45% (P < 0.001) in total population, 25.24% in women and 57.35% in men. CONCLUSION: These results provided evidence that the temporal relationship between BMI and insulin resistance is reciprocal and a higher BMI precedes hyperinsulinemia in Chinese adults. This relationship plays an essential role in the development of hypertension, while there is a difference between women and men.

Sex difference in the incidence of stroke and its corresponding influence factors: results from a follow-up 8.4 years of rural China hypertensive prospective cohort study.

BACKGROUND: Few studies investigate sex difference in stroke incidence in rural China hypertensive population. METHODS: A total of 5097 hypertensive patients aged ≥35 years (mean age, 56.3 ± 11.2 years; 43.8% men) were included in our analysis with a median follow-up 8.4 years in Fuxin county of Liaoning province in China. Cox proportional hazard models were used to analyze the association between the potential factors and incident stroke. RESULTS: We observed 501 new strokes (310 ischemic, 186 hemorrhagic, and 5 unclassified stroke) during the follow-up. The overall incidence of stroke was 1235.21 per 100,000 person-years; for men, the rates were 1652.51 and 920.80 for women. This sex difference in all stroke can be explained by approximately 25% through age, systolic blood pressure, body mass index, low-density lipoprotein-cholesterol, current smoking, current drinking, antihypertensive drugs, education and physical activity. Subgroup analysis indicated that in hemorrhagic stroke this sex difference was more remarkable (63.89% can be explained). CONCLUSIONS: The incidence of stroke was higher in men than that in women and this difference was partly explained by several traditional cardiovascular risk factors.

Non-traditional lipid profiles associated with ischemic stroke not hemorrhagic stroke in hypertensive patients: results from an 8.4 years follow-up study.

BACKGROUND: Studies have shown that non-traditional lipid profiles have a better association with stroke than traditional blood lipids in clinical applications, other studies have drawn different conclusions. METHODS: This study was a large-scale study with a median follow-up of 8.4 years. The hazard ratio (HR) and 95% Confidence interval (CI) of lipid variables for risk of incident stroke were analyzed by multivariable Cox proportional hazard models. RESULTS: During the follow-up, 502 new strokes (310 ischemic, 187 hemorrhagic, and 5 unclassified strokes) occurred among the 5099 hypertensive patients. Comparing with the lowest quarter, the HR of future ischemic stroke (IS) in the highest were 1.41(95%CI, 1.03-1.92) for TC, 1.60 (95%CI, 1.15-2.22) for TG, 1.03 (95%CI, 0.75-1.42) for HDL-C, 1.77 (95%CI, 1.29-2.44) for LDL-C, 1.42 (95%CI, 1.03-1.94) for non-HDL, 2.09 (95%CI, 1.45-3.00) for TC/HDL, 2.08 (95%CI, 1.46-2.96) for LDL/HDL, 1.86 (95%CI 1.33-2.60) for TG/HDL, respectively. No significant association was observed between lipid-related indicators and hemorrhagic stroke. The results of statistical differences showed that the correlation between LDL/HDL and the risk of ischemic stroke in non-traditional lipids was higher than that of other traditional lipids (P < 0.001), except for LDL (P = 0.056). CONCLUSIONS: We didn't find that HDL was associated with the risk of stroke and all the lipid parameters were not associated with the risk of hemorrhagic stroke. LDL/HDL was associated with a higher risk of ischemic stroke than other lipids and should be considered for clinical diagnosis and future disease prevention.

Association of interpregnancy interval and risk of adverse pregnancy outcomes in woman by different previous gestational ages.

BACKGROUND: With an increasing proportion of multiparas, proper interpregnancy intervals (IPIs) are urgently needed. However, the association between IPIs and adverse perinatal outcomes has always been debated. This study aimed to explore the association between IPIs and adverse outcomes in different fertility policy periods and for different previous gestational ages. METHODS: We used individual data from China's National Maternal Near Miss Surveillance System between 2014 and 2019. Multivariable Poisson models with restricted cubic splines were used. Each adverse outcome was analyzed separately in the overall model and stratified models. The stratified models included different categories of fertility policy periods (2014-2015, 2016-2017, and 2018-2019) and infant gestational age in previous pregnancy (<28 weeks, 28-36 weeks, and ≥37 weeks). RESULTS: There were 781,731 pregnancies enrolled in this study. A short IPI (≤6 months) was associated with an increased risk of preterm birth (OR [95% CI]: 1.63 [1.55, 1.71] for vaginal delivery [VD] and 1.10 [1.03, 1.19] for cesarean section [CS]), low Apgar scores and small for gestational age (SGA), and a decreased risk of diabetes mellitus in pregnancy, preeclampsia or eclampsia, and gestational hypertension. A long IPI (≥60 months) was associated with an increased risk of preterm birth (OR [95% CI]: 1.18 [1.11, 1.26] for VD and 1.39 [1.32, 1.47] for CS), placenta previa, postpartum hemorrhage, diabetes mellitus in pregnancy, preeclampsia or eclampsia, and gestational hypertension. Fertility policy changes had little effect on the association of IPIs and adverse maternal and neonatal outcomes. The estimated risk of preterm birth, low Apgar scores, SGA, diabetes mellitus in pregnancy, and gestational hypertension was more profound among women with previous term births than among those with preterm births or pregnancy loss. CONCLUSION: For pregnant women with shorter or longer IPIs, more targeted health care measures during pregnancy should be formulated according to infant gestational age in previous pregnancy.

Maternal Characteristics and Prevalence of Infants Born Small for Gestational Age.

Importance: Being born small for gestational age (SGA) is a risk factor for neonatal mortality and adverse outcomes in the short and long term. The maternal profile in China has substantially changed over the past decade, which may affect the risk of infants born SGA. Objectives: To analyze the prevalence of infants born SGA from 2012 through 2020 and explore the association of maternal sociodemographic characteristics and other factors with that prevalence. Design, Setting, and Participants: This cross-sectional study examined data from the National Maternal Near Miss Surveillance System on women who delivered singleton live births at gestational ages of 28 to 42 weeks from January 1, 2012, through December 31, 2020, in China. Statistical analysis was performed from December 2022 to September 2023. Exposures: Characteristics of delivery (year, region of country, and hospital level), mother (age, educational level, marital status, prenatal visits, parity, preexisting diseases, or prenatal complications), and newborn (birth weight, sex, and gestational age). Main Outcomes and Measures: Prevalence of infants born SGA stratified by severity and by region of the country, changes in prevalence based on log-linear Poisson regression with robust variance, and association of maternal characteristics with changes in prevalence of infants born SGA between 2012 and 2020 based on the Fairlie nonlinear mean decomposition. Results: Among 12 643 962 births (6 572 548 [52.0%] male; median gestational age, 39 weeks [IQR, 38-40 weeks]), the overall weighted prevalence of infants born SGA was 6.4%, which decreased from 7.3% in 2012 to 5.3% in 2020, translating to a mean annual decrease rate of 3.9% (95% CI, 3.3%-4.5%). The prevalence of infants born SGA decreased from 2.0% to 1.2% for infants with severe SGA birth weight and from 5.3% to 4.1% for those with mild to moderate SGA birth weight. The mean annual rate of decrease was faster for infants with severe SGA birth weight than for those with mild to moderate SGA birth weight (5.9% [95% CI, 4.6%-7.1%] vs 3.2% [95% CI, 2.6%-3.8%]) and was faster for the less developed western (5.3% [95% CI, 4.4%-6.1%]) and central (3.9% [95% CI, 2.9%-4.8%]) regions compared with the eastern region (2.3% [95% CI, 1.1%-3.4%]). Two-thirds of the observed decrease in the prevalence of infants born SGA could be accounted for by changes in maternal characteristics, such as educational level (relative association, 19.7%), age (relative association, 18.8%), prenatal visits (relative association, 20.4%), and parity (relative association, 19.4%). Conversely, maternal preexisting diseases or prenatal complications counteracted the decrease in the prevalence of infants born SGA (-6.7%). Conclusions and Relevance: In this cross-sectional study of births in China from 2012 to 2020, maternal characteristics changed and the prevalence of infants born SGA decreased. Future interventions to reduce the risk of infants born SGA should focus on primary prevention.

High specific and ultrasensitive isothermal detection of microRNA by padlock probe-based exponential rolling circle amplification.

In this paper, a padlock probe-based exponential rolling circle amplification (P-ERCA) assay is developed for highly specific and sensitive detection of microRNA (miRNA). The padlock probe is composed of a hybridization sequence to miRNA and a nicking site for nicking endonuclease. Using the miRNA as a template, specific ligation to the padlock probe and linear rolling circle reaction (LRCA) are achieved under isothermal conditions. After multiple nicking reactions, many copies of short DNA products are successively produced and then used as triggers in next circle amplification. Thus, a small amount of miRNAs are converted to a large number of triggers to initiate the rolling circle amplification reaction, and circular exponential signal amplification is achieved. This padlock probe-based exponential rolling circle amplification assay exhibits a remarkable sensitivity of 0.24 zmol using optimized sequences of the padlock probe. The target-dependent circularization of the padlock probe and the ligation reaction could improve the specificity effectively, leading to single-nucleotide difference discrimination between miRNA family members. The miRNA analysis in human lung cells was performed with this method. The result indicates this highly sensitive P-ERCA strategy will become a promising miRNA quantification method in early clinical diagnostics.

Association of Daytime-Only, Nighttime-Only, and Compound Heat Waves With Preterm Birth by Urban-Rural Area and Regional Socioeconomic Status in China.

Importance: Associations between heat waves and preterm birth (PTB) have been reported. However, associations of daytime-only, nighttime-only, and compound heat waves with PTB have yet to be explored at a national level. Furthermore, possible heterogeneity across urban-rural communities with different socioeconomic statuses needs to be explored. Objective: To examine the association between daytime-only, nighttime-only, and compound heat waves and PTB in China and to find variations between urban and rural regions. Design, Setting, and Participants: This case-crossover study used nationwide representative birth data between January 1, 2012, and December 31, 2019, from China's National Maternal Near Miss Surveillance System. This multisite study covered 30 provinces in China and ensured the representation of urban and rural populations across 3 socioeconomic regions. Singleton live births delivered in the warm seasons from April to October during the study period were included. Exclusion criteria consisted of gestational age younger than 20 or older than 45 weeks, maternal ages younger than 13 or older than 50 years, conception dates earlier than 20 weeks before January 1, 2012, and later than 45 weeks before December 31, 2019, and an inconsistent combination of birthweight and gestational age according to growth standard curves of Chinese newborns. Data were analyzed from September 10, 2021, to April 25, 2023. Exposures: Eighteen definitions of heat waves by 3 distinct types, including daytime only (only daily maximum temperature exceeds thresholds), nighttime only (only daily minimum temperature exceeds thresholds), and compound (both daily maximum and minimum temperature exceeds thresholds) heat waves, and 6 indexes, including 75th percentile of daily temperature thresholds for 2 or more (75th-D2), 3 or more (75th-D3), or 4 or more (75th-D4) consecutive days and 90th percentile of daily temperature thresholds for 2 or more (90th-D2), 3 or more (90th-D3), and 4 or more (90th-D4) consecutive days. Main Outcomes and Measures: Preterm births with less than 37 completed weeks of gestation. Results: Among the 5 446 088 singleton births in the final analytic sample (maternal mean [SD] age, 28.8 [4.8] years), 310 384 were PTBs (maternal mean [SD] age, 29.5 [5.5] years). Compared with unexposed women, exposure of pregnant women to compound heat waves in the last week before delivery was associated with higher risk for PTB, with the adjusted odds ratios (AORs) ranging from 1.02 (95% CI, 1.00-1.03) to 1.04 (95% CI, 1.01-1.07) in 6 indexes. For daytime-only heat wave exposures, AORs ranged from 1.03 (95% CI, 1.01-1.05) to 1.04 (95% CI, 1.01-1.08) in the 75th-D4, 90th-D2, 90th-D3, and 90th-D4 indexes. Such associations varied by rural (AOR range, 1.05 [95% CI, 1.01-1.09] to 1.09 [95% CI, 1.04-1.14]) and urban (AOR range, 1.00 [95% CI, 0.98-1.02] to 1.01 [95% CI, 0.99-1.04]) regions during exposure to daytime-only heat waves in the 75th-D3 and 90th-D3 indexes. Conclusions and Relevance: In this case-crossover study, exposure to compound and daytime-only heat waves in the last week before delivery were associated with PTB, particularly for pregnant women in rural regions exposed to daytime-only heat waves. These findings suggest that tailored urban-rural preventive measures may improve maternal health in the context of climate change.

Disparities of Heatwave-Related Preterm Birth in Climate Types - China, 2012-2019.

What is already known about this topic?: An association between prenatal heatwave exposure and the risk of preterm birth was found. However, the disparities in heatwave-related preterm birth across different climate types have not been examined. What is added by this report?: This nationwide case-crossover study investigated the association between heatwave exposure and preterm birth across different Köppen-Geiger climate types. Among pregnant women residing in the arid-desert-cold climate type, exposure to compound heatwaves was found to be associated with a significantly higher risk of preterm birth {adjusted odds ratios (AORs) ranged from 1.55 [95% confidence interval ( CI): 1.21-1.97] to 2.11 (95% CI: 1.35-3.31)}. In contrast, among pregnant women residing in the tropical monsoonal climate type, exposure to daytime-only heatwaves was associated with an increased risk of preterm birth [AORs ranged from 1.25 (95% CI: 1.03-1.51) to 1.37 (95% CI: 1.05-1.77)]. What are the implications for public health practice?: Specific interventions should be implemented in China to mitigate the risk of preterm birth related to heatwaves, particularly for pregnant women residing in arid-desert-cold and tropical monsoonal climates.

Simultaneous determination of reactive oxygen and nitrogen species in mitochondrial compartments of apoptotic HepG2 cells and PC12 cells based on microchip electrophoresis-laser-induced fluorescence.

Determination of intracellular bioactive species will afford beneficial information related to cell metabolism, signal transduction, cell function, and disease treatment. In this study, the first application of a microchip electrophoresis-laser-induced fluorescence (MCE-LIF) method for concurrent determination of reactive oxygen species (ROS) and reactive nitrogen species (RNS), i.e., superoxide (O(2)(-•)) and nitric oxide (NO) in mitochondria, was developed using fluorescent probes 2-chloro-1,3-dibenzothiazolinecyclohexene (DBZTC) and 3-amino,4-aminomethyl-2',7'-difluorescein (DAF-FM), respectively. Potential interference of intracellular dehydroascorbic acid (DHA) and ascorbic acid (AA) for NO detection with DAF-FM was eliminated through oxidation of AA with the addition of ascorbate oxidase, followed by subsequent MCE separation. Fluorescent products of O(2)(-•) and NO, DBZTC oxide (DBO), and DAF-FM triazole (DAF-FMT) showed excellent baseline separation within 1 min with a running buffer of 40 mM Tris solution (pH 7.4) and a separating electric field of 500 V/cm. The levels of DBO and DAF-FMT in mitochondria isolated from normal HepG2 cells and PC12 cells were evaluated using this method. Furthermore, the changes of DBO and DAF-FMT levels in mitochondria isolated from apoptotic HepG2 cells and PC12 cells could also be detected. The current approach was proved to be simple, fast, reproducible, and efficient. Measurement of the two species with the method will be beneficial to understand ROS/RNS distinctive functions. In addition, it will provide new insights into the role that both species play in biological systems.