Susceptibility gene identification and risk evaluation model construction by transcriptome-wide association analysis for salt sensitivity of blood pressure.

BACKGROUND: Salt sensitivity of blood pressure (SSBP) is an intermediate phenotype of hypertension and is a predictor of long-term cardiovascular events and death. However, the genetic structures of SSBP are uncertain, and it is difficult to precisely diagnose SSBP in population. So, we aimed to identify genes related to susceptibility to the SSBP, construct a risk evaluation model, and explore the potential functions of these genes. METHODS AND RESULTS: A genome-wide association study of the systemic epidemiology of salt sensitivity (EpiSS) cohort was performed to obtain summary statistics for SSBP. Then, we conducted a transcriptome-wide association study (TWAS) of 12 tissues using FUSION software to predict the genes associated with SSBP and verified the genes with an mRNA microarray. The potential roles of the genes were explored. Risk evaluation models of SSBP were constructed based on the serial P value thresholds of polygenetic risk scores (PRSs), polygenic transcriptome risk scores (PTRSs) and their combinations of the identified genes and genetic variants from the TWAS. The TWAS revealed that 2605 genes were significantly associated with SSBP. Among these genes, 69 were differentially expressed according to the microarray analysis. The functional analysis showed that the genes identified in the TWAS were enriched in metabolic process pathways. The PRSs were correlated with PTRSs in the heart atrial appendage, adrenal gland, EBV-transformed lymphocytes, pituitary, artery coronary, artery tibial and whole blood. Multiple logistic regression models revealed that a PRS of P < 0.05 had the best predictive ability compared with other PRSs and PTRSs. The combinations of PRSs and PTRSs did not significantly increase the prediction accuracy of SSBP in the training and validation datasets. CONCLUSIONS: Several known and novel susceptibility genes for SSBP were identified via multitissue TWAS analysis. The risk evaluation model constructed with the PRS of susceptibility genes showed better diagnostic performance than the transcript levels, which could be applied to screen for SSBP high-risk individuals.

Milk yield variation partially attributed to blood oxygen-mediated neutrophil activation in lactating dairy goats.

Blood oxygen is an essential component for numerous biological processes of mammalian animals. Milk production of ruminants largely relies on the supply of nutrients, such as glucose, amino acids and fatty acids. To define the regulatory role of blood oxygen availability in regard to milk production, seventy-five healthy Guanzhong dairy goats with similar body weight, days in milk and parities were selected. For each animal, milk yield was recorded and milk sample was collected to determine compositions. Milk vein blood was collected to determine parameters including blood gas, physio-biochemistry and haematology. Another blood sample was prepared for transcriptome and RT-qPCR. Results showed that both pressure of oxygen (pO2) in the milk vein (positively) and numbers of neutrophils in mammary vein (negatively) were associated with milk yield of the animals. To learn the role of pO2 in blood cell functionality, twelve animals (six with higher yield (H-group) and six with lower yield (L-group)) from seventy-five goats were selected. Compared with animals in L-group, goats in H-group were higher in pO2 but lower in pCO2, lactate, lactate dehydrogenase activity and neutrophil abundance in milk vein, compared with L-group. The blood transcriptome analysis suggested that compared with L-group, animals in H-group were depressed in functionality including neutrophil activation and metabolic pathways including glycolysis, NF-κB and HIF-1. Our result revealed that lower milk production could be associated with neutrophil activation responding to low pO2 in the mammary vein. In the meantime, we highlighted the potential importance of blood oxygen as a milk yield regulator.

Neuropeptides and hormones in hypothalamus-pituitary axis of Chinese sturgeon (Acipenser sinensis).

The hypothalamus and pituitary serve as important neuroendocrine center, which is able to secrete a variety of neuropeptides and hormones to participate in the regulation of reproduction, growth, stress and feeding in fish. Chinese sturgeon is a basal vertebrate lineage fish with a special evolutionary status, but the information on its neuroendocrine system is relatively scarce. Using the transcriptome data on the hypothalamus-pituitary axis of Chinese sturgeon as reference, we found out 46 hypothalamus neuropeptide genes, which were involved in regulation of reproduction, growth, stress and feeding. The results of sequence alignment showed that the neuroendocrine system of Chinese sturgeon evolves slowly, which confirms that Chinese sturgeon is a species with a slow phenotypic evolution rate. In addition, we also isolated six pituitary hormones genes from Chinese sturgeon, including reproductive hormones: follicle-stimulating homone (FSH) and luteinizing hormone (LH), growth-related hormones: growth hormone (GH)/prolactin (PRL)/somatolactin (SL), and stress-related hormone gene: proopiomelanocortin (POMC). Similar to teleost, immunostaining localization analysis in Chinese sturgeon pituitary showed that LH and FSH were located in the pituitary proximal pars distalis, SL was located in the pituitary rostral pars distalis, and POMC was located in the pituitary pars intermedia and pituitary rostral pars distalis. This study will give a contribution to enrich our information on the neuroendocrine system in Chinese sturgeon.

The prevalence of disability and associated factors among community adults in the baseline of CHCN-BTH Cohort Study.

BACKGROUND: Disability was a major public health problem in China. However, the prevalence of disabilities in community-dwelling adults and their relationships to chronic physical conditions were unclear. We aimed to estimate the prevalence of disabilities and associated factors among a large community-based cohort in China. METHODS: Participants who were local permanent residents aged 18 years or above and completed the disability assessments were selected from the Cohort study on Chronic Disease of Communities Natural Population in Beijing, Tianjin and Hebei (CHCN-BTH) from 2017 to 2019. Disability was assessed using five questions about impairments and activity limitations based on the International Classification of Functioning (ICF), Disability and Health. Univariate, multivariate and multilevel logistic regressions were conducted to estimate the associations between disabilities and associated factors. RESULTS: Totally, 12,871 community-dwelling adults completed the survey. Among of them, 12.9% (95% CI: 12.3%-13.5%) reported having any disability. The prevalence of any disability was significantly higher in participants who were older age, widowed, retired and smokers, had higher BMI, average monthly income < 5000 RMB, lower education level, lower physical exercise frequency and heavy physical labor. Multilevel logistic regressions showed that there were significant associations between disabilities with chronic physical conditions, especially in the vision impairment with lower back pain, and hearing impairment as well as difficulty walking without special equipment with injuries. CONCLUSIONS: Many Chinese adults suffered from disabilities. Sustained efforts should be made to develop specific population-based health promotion and prevention programs for disabilities in China. TRAIL REGISTRATION: ChiCTR1900024725 (25/07/2019).

Combined effects of ambient air pollution and PM2.5 components on renal function and the potential mediation effects of metabolic risk factors in China.

Growing evidence links long-term air pollution exposure with renal function. However, little research has been conducted on the combined effects of air pollutant mixture on renal function and multiple mediation effects of metabolic risk factors. This study enrolled 8996 adults without chronic kidney disease (CKD) at baseline from the CHCN-BTH cohort study. Three-year exposure to air pollutants [particulate matter ≤ 2.5 µm (PM2.5), PM10, PM1, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO)] and PM2.5 components [black carbon (BC), ammonium (NH4+), nitrate (NO3-), sulfate (SO42-) and organic matter (OM)] were assessed using well-validated machine learning methods. Linear mixed models were applied to investigate the associations between air pollutants and estimated glomerular filtration rate (eGFR). Quantile G-computation was used to assess the combined effects of pollutant mixtures. Causal mediation analysis and Bayesian mediation analysis were employed to estimate the mediation effects of metabolic risk factors. An interquartile range increases in BC (-0.256, 95 %CI: -0.331, -0.180) and OM (-0.603, 95 %CI: -0.810, -0.397) were significantly associated with eGFR decline; while O3 (1.151, 95 %CI: 0.813, 1.489), PM10 (0.721, 95 %CI: 0.309, 1.133), NH4+ (0.990, 95 %CI: 0.638, 1.342), and NO3- (0.610, 95 %CI: 0.405, 0.815) were associated with higher eGFR. The combined effect of the PM2.5 component mixture was found to be associated with lower eGFR (-1.147, 95 % CI: -1.456, -0.839), with OM contributing 72.4 % of the negative effect. Univariate mediation analyses showed that high-density lipoprotein (HDL) mediated 7.1 %, 6.9 %, and 6.1 % effects of O3, BC, and OM, respectively. However, these mediation effects were not significant in Bayesian mediation analysis. These findings suggest the effect of the PM2.5 component mixture on eGFR decline and the strong contribution of OM. Metabolic risk factors may not mediate the effects of air pollutants. Further study is warranted to clarify the potential mechanisms involved.

The mediation effect of lipids, blood pressure and BMI between air pollutant mixture and atherosclerotic cardiovascular disease: The CHCN-BTH cohort study.

BACKGROUND: The combine effect of air pollutant mixture on atherosclerotic cardiovascular disease (ASCVD) remain undefined. This study aims to explore the association between long-term exposure of air pollutants and ASCVD, focusing on the mediating role of lipids, blood pressure and BMI. METHODS: This study was based on the CHCN-BTH cohort study. The annual concentrations of air pollutants and PM2.5 constituents were sourced from in the Tracking Air Pollution in China (TAP) and ChinaHighAirPollutants (CHAP) datasets from 2014 to 2019. A Cox mixed-effects model was used to investigate the associations between long-term exposure of air pollutants and ASCVD. The combined impact of the air pollutant mixture was assessed using Quantile g-Computation. Stratified, sensitivity, and mediation analyses were conducted. RESULTS: A total of 27,134 participants aged 18-80 were recruited in the present study. We found that each IQR increase of PM2.5, PM1, NO2, O3, BC, SO42-, and OM were significantly associated with the incidence of ASCVD, the hazard ratios (HRs) and 95 % confidence interval (CI) were 1.55 (1.35, 1.78), 1.46 (1.27, 1.67), 1.30 (1.21, 1.39), 1.66 (1.41,1.95), 2.14 (1.63, 2.83), 1.65 (1.25, 2.17) and 1.92(1.52, 2.45), respectively. The combined effect of air pollutant mixture on ASCVD was 1.79 (1.46, 2.20), PM2.5 contributed 83.3 % to this combined effect. Mediation effect models suggested that air pollutants and ASCVD might be mediated through SBP, DBP, HDL-C, LDL-C, hsCRP and BMI (mediation proportion range from 1.3 % to 26.1 %), Notably, HDL-C played mediation roles of 11.3 % (7.0 %, 18.4), 26.1 % (17.7 %, 38.1 %) and 25.4 % (15.4, 47.7 %) in the effects of long-term exposure to PM2.5, PM1 and OM on ASCVD, respectively. CONCLUSIONS: Long-term, high-level air pollutant exposure was significantly associated with an elevated risk of ASCVD, particularly for PM2.5. Blood pressure, lipids and BMI, especially HDL-C, may mediate the effects of air pollutants exposure on ASCVD.

Impact of lipoprotein(a) level on cardiometabolic disease in the Chinese population: The CHCN-BTH Study.

BACKGROUND: The emergence of promising compounds to lower lipoprotein(a) [Lp(a)] has increased the need for a precise characterisation and comparability assessment of Lp(a)-associated cardiometabolic disease risk. This study aimed to evaluate the distribution of Lp(a) levels in a Chinese population and characterise the association with cardiometabolic diseases. METHODS: We assessed data from individuals from the Cohort Study on Chronic Diseases of the General Community Population in the Beijing-Tianjin-Hebei Region project. All Lp(a) measurements were performed in the same hospital. The cardiometabolic diseases considered were coronary heart disease (CHD), stroke, hypertension and type 2 diabetes (T2DM). RESULTS: A total of 25343 individuals were included in the study. The median level of Lp(a) was 11.9 mg/dl (IQR 5.9 to 23.7 mg/dl), and higher Lp(a) levels showed a significant concentration-dependent association with CHD risk. Individuals with Lp(a) levels lower than the 25th percentile were at increased risk of hypertension (OR: 1.15, 95% CI: 1.06-1.25) and T2DM (OR: 1.15, 95% CI: 1.03-1.28); however, Lp(a) levels were not significantly associated with stroke. The addition of Lp(a) levels to the prognostic model led to a marginal but significant C-index, integrated discrimination improvement and net reclassification improvement. CONCLUSIONS: In this large sample size study, we observed that elevated Lp(a) levels were significantly associated with CHD. Furthermore, we found that the lowest Lp(a) levels were also significantly associated with hypertension and T2DM. These results provide evidence for differential approaches to higher levels of Lp(a) in individuals with different cardiometabolic diseases.

SHED-derived exosomes promote LPS-induced wound healing with less itching by stimulating macrophage autophagy.

High-quality cutaneous wound healing is associated with rapid wound closure and a comfortable healing process. Currently, exosomes derived from mesenchymal stem cells displayed a prominent therapeutic effect on skin wound closure. But the therapeutic approaches for wound itching are very limited in clinical. Stem cells from human exfoliated deciduous teeth (SHED) may offer a unique exosome resource for cell-free therapeutics in potential clinical applications. Here, we investigated the common mechanisms underlying wound closure and unpleasant sensation of itching, focusing on the contribution of the SHED-derived exosome to immune response and wound itching during healing. The effects of SHED-derived exosomes on inflammatory wound healing were examined using lipopolysaccharide (LPS)-induced wounds in a mouse model. We found prolonged inflammation and distinct itch responses in skin wound tissue during LPS-induced wound healing. SHED-derived exosomes facilitated LPS-induced wound closure and relieved wound itching. Therefore, they are ideal for the treatment of wound healing. Macrophages in skin wound tissues are responsible for autophagy during wound healing. Macrophage autophagy also regulates cell proliferation, migration, and neuronal signal transduction in vitro. SHED-derived exosomes containing miR-1246 enhanced autophagy by regulating macrophage function through the AKT, ERK1/2, and STAT3 signaling pathways. Thus, SHED-derived exosomes promote wound healing with less itching in an LPS-induced wound model by stimulating macrophage autophagy, which has implications for the treatment of inflammatory wound healing.

Mechanism of Cyclic Tensile Stress in Osteogenic Differentiation of Human Periodontal Ligament Stem Cells.

Human periodontal ligament stem cells (hPDLSCs) can undergo osteogenic differentiation under induction conditions. Cyclic tensile stress (CTS) can stimulate stem cell osteogenic differentiation. The present study explored the mechanism of CTS in hPDLSC osteogenic differentiation. The hPDLSCs of the 4th passage were selected. hPDLSCs were subjected to CTS with deformation of 10% elongation at 0.5 Hz for 1, 4, 8, 12 and 24 h. ALP activity and staining, ARS staining and detection of expressions of osteogenesis-related genes (RUNX2, OPN, Sp7 and OCN) were used to assess hPDLSC osteogenic differentiation ability. microRNA (miR)-129-5p and BMP2 expression and p-Smad1/5 level were detected under CTS stimulation. The binding relationship between miR-129-5p and BMP2 was predicted and verified. The osteogenic differentiation ability of CTS-treated hPDLSCs was evaluated after intervention of miR-129-5p and BMP2. CTS induced hPDLSC osteogenic differentiation, as manifested by increased ALP activities, osteogenesis-related gene expressions and mineralized nodules, together with positive ALP staining. CTS inhibited miR-129-5p expression, and promoted BMP2 expression and p-Smad1/5 level in hPDLSCs. miR-129-5p targeted BMP2. Overexpressed miR-129-5p or silenced BMP2 prevented hPDLSC osteogenic differentiation ability. We demonstrated that CTS inhibited miR-129-5p expression, and then activated the BMP2/Smad pathway, thereby showing stimulative effects on hPDLSC osteogenic differentiation.

Association of long-term exposure to ambient particulate pollution with stage 1 hypertension defined by the 2017 ACC/AHA Hypertension Guideline and cardiovascular disease: The CHCN-BTH cohort study.

BACKGROUND: Evidence regarding the effects of ambient air pollution on new stage 1 hypertension defined by the 2017 ACC/AHA Hypertension Guideline remains sparse. OBJECTIVES: To investigate the association of long-term exposure to ambient PM2.5 with stage 1 hypertension and to explore the mediating and modifying effects of PM2.5 on cardiovascular disease (CVD). METHODS: A total of 32,135 participants aged 18-80 years were recruited in 2017. The three-year (2014-2016) average PM2.5 concentrations were assessed by a spatial statistical model. Blood pressure (BP) was divided into four categories according to the 2017 ACC/AHA Hypertension Guideline: normal BP (SBP<120 mmHg and DBP<80 mmHg), elevated BP (SBP 120-129 mmHg and DBP<80 mmHg), stage 1 hypertension (SBP 130-139 mmHg or DBP 80-89 mmHg), and stage 2 hypertension (SBP≥140 mmHg or DBP≥90 mmHg or taking antihypertensive medications). The associations of PM2.5 with BP categories were estimated by two-level generalized linear mixed models. Analyses stratified by age, mediation and interaction analyses of PM2.5 and stage 1 hypertension with CVD were performed. RESULTS: We detected a positive significant association between long-term exposure to PM2.5 and stage 1 hypertension. Compared to normal BP, the OR was 1.05 (95% CI: 1.02, 1.08) per 10 µg/m3 increase in PM2.5. The association was stronger than that of elevated BP but weaker than that of stage 2 hypertension. Stage 1 hypertension only partially mediated the association between PM2.5 and CVD, and the mediation proportions ranged from 1.55% to 11.00%. However, it modified the association between PM2.5 and CVD, which was greater in participants with stage 1 hypertension (OR: 1.66; 95% CI: 1.43, 1.93) than in participants with normal BP (OR: 1.32; 95% CI: 1.11, 1.57), with Pinteraction<0.001. In the analysis stratified by age, the above associations were age-specific, and significant associations were only observed in the young and middle-aged (<60 years) groups. CONCLUSIONS: Long-term exposure to ambient PM2.5 was significantly associated with stage 1 hypertension. This earlier stage of hypertension may be a trigger BP range for adverse effects of air pollution in the development of hypertension and CVD, especially in young and middle-aged individuals.

Association study of fasting blood glucose and salt sensitivity of blood pressure in community population: The EpiSS study.

BACKGROUND AND AIMS: To evaluate the association between fasting blood glucose (FBG) and salt sensitivity of blood pressure (SSBP). METHODS AND RESULTS: This study is based on the baseline survey of systemic epidemiology of salt sensitivity study. Subjects were classified into salt sensitive (SS) and salt resistant groups according to blood pressure (BP) changes during the modified Sullivan's acute oral saline load and diuresis shrinkage test. Multivariate logistic and linear regression were used to evaluate associations between FBG with SS or BP changes. A total of 2051 participants were included in the analyses with 581 (28.33%) for SS. Multiple analysis showed that for every interquartile range increase in FBG, the OR (95%CI) for SS was 1.140 (1.069, 1.215), ß (95%CI) for mean arterial pressure change (ΔMAP1), systolic and diastolic BP changes during saline load were 0.421 (0.221, 0.622), 0.589 (0.263, 0.914) and 0.340 (0.149, 0.531), respectively. Compared to the lowest FBG quartile (Q1), the OR (95%CI) for SS in Q3 and Q4 were 1.342 (1.014, 1.776) and 1.577 (1.194, 2.084), respectively. Compared to subjects with normal FBG, the ß (95%CI) for ΔMAP1 was 0.973 (0.055, 1.891) in subjects with impaired FBG, and was 1.449 (0.602, 2.296) in patients with diabetes mellitus. Stratified analyses showed significant and stronger associations between FBG with SSBP in youngers, females, hypertensives, non-diabetics, non-current smokers and non-current drinkers. CONCLUSION: Our findings suggest FBG is an independent, dose-dependent associated factor for SSBP, and prevention of SS focusing on controlling FBG elevation in the early stage is important.

Association of Lipoprotein (a) variants with risk of cardiovascular disease: a Mendelian randomization study.

BACKGROUND: There is a well-documented empirical relationship between lipoprotein (a) [Lp(a)] and cardiovascular disease (CVD); however, causal evidence, especially from the Chinese population, is lacking. Therefore, this study aims to estimate the causal association between variants in genes affecting Lp(a) concentrations and CVD in people of Han Chinese ethnicity. METHODS: Two-sample Mendelian randomization analysis was used to assess the causal effect of Lp(a) concentrations on the risk of CVD. Summary statistics for Lp(a) variants were obtained from 1256 individuals in the Cohort Study on Chronic Disease of Communities Natural Population in Beijing, Tianjin and Hebei. Data on associations between single-nucleotide polymorphisms (SNPs) and CVD were obtained from recently published genome-wide association studies. RESULTS: Thirteen SNPs associated with Lp(a) levels in the Han Chinese population were used as instrumental variables. Genetically elevated Lp(a) was inversely associated with the risk of atrial fibrillation [odds ratio (OR), 0.94; 95% confidence interval (95%CI), 0.901-0.987; P = 0.012)], the risk of arrhythmia (OR, 0.96; 95%CI, 0.941-0.990; P = 0.005), the left ventricular mass index (OR, 0.97; 95%CI, 0.949-1.000; P = 0.048), and the left ventricular internal dimension in diastole (OR, 0.97; 95%CI, 0.950-0.997; P = 0.028) according to the inverse-variance weighted method. No significant association was observed for congestive heart failure (OR, 0.99; 95% CI, 0.950-1.038; P = 0.766), ischemic stroke (OR, 1.01; 95%CI, 0.981-1.046; P = 0.422), and left ventricular internal dimension in systole (OR, 0.98; 95%CI, 0.960-1.009; P = 0.214). CONCLUSIONS: This study provided evidence that genetically elevated Lp(a) was inversely associated with atrial fibrillation, arrhythmia, the left ventricular mass index and the left ventricular internal dimension in diastole, but not with congestive heart failure, ischemic stroke, and the left ventricular internal dimension in systole in the Han Chinese population. Further research is needed to identify the mechanism underlying these results and determine whether genetically elevated Lp(a) increases the risk of coronary heart disease or other CVD subtypes.

Novel Pituitary Actions of TAC4 Gene Products in Teleost.

Tachykinin 4 (TAC4) is the latest member of the tachykinin family involved in several physiological functions in mammals. However, little information is available about TAC4 in teleost. In the present study, we firstly isolated TAC4 and six neurokinin receptors (NKRs) from grass carp brain and pituitary. Sequence analysis showed that grass carp TAC4 could encode two mature peptides (namely hemokinin 1 (HK1) and hemokinin 2 (HK2)), in which HK2 retained the typical FXGLM motif in C-terminal of tachyinin, while HK1 contained a mutant VFGLM motif. The ligand-receptor selectivity showed that HK2 could activate all 6 NKRs but with the highest activity for the neurokinin receptor 2 (NK2R). Interestingly, HK1 displayed a very weak activation for each NKR isoform. In grass carp pituitary cells, HK2 could induce prolactin (PRL), somatolactin α (SLα), urotensin 1 (UTS1), neuromedin-B 1 (NMB1), cocaine- and amphetamine-regulated transcript 2 (CART2) mRNA expression mediated by NK2R and neurokinin receptor 3 (NK3R) via activation cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA), phospholipase C (PLC)/inositol 1,4,5-triphosphate (IP3)/protein kinase C (PKC) and calcium2+ (Ca2+)/calmodulin (CaM)/calmodulin kinase-II (CaMK II) cascades. However, the corresponding stimulatory effects triggered by HK1 were found to be notably weaker. Furthermore, based on the structural base for HK1, our data suggested that a phenylalanine (F) to valine (V) substitution in the signature motif of HK1 might have contributed to its weak agonistic actions on NKRs and pituitary genes regulation.

Associations between ambient air pollution and mortality from all causes, pneumonia, and congenital heart diseases among children aged under 5 years in Beijing, China: A population-based time series study.

BACKGROUND: Previous studies have mainly focused on the associations between particulate matters and infant mortality. However, evidence regarding the associations between gaseous pollutants and mortality among children aged <5 years remains sparse. OBJECTIVES: The aim of this study was to investigate the associations between ambient air pollution and death among children aged <5 years in Beijing, China, and explore the impact of age, gender and specific causes of death on these associations. METHODS: Concentrations of ambient air pollution and the number of deaths among children aged <5 years in Beijing from January 2014 to September 2016 were extracted from authoritative electronic databases. The associations were estimated for a single-month lag from the current month up to the previous 5 months (lag0-lag5) and moving averages of the current and previous months (lag01-lag05) using generalized additive Poisson regression (adjusted for time trends, season, meteorological variables and holidays). Subgroup analyses related to age, gender and specific diseases were performed. Two-pollutant models were used to evaluate the possible role of single pollutants. RESULTS: Sulfur dioxide (SO2), nitrogen dioxide (NO2) and carbon monoxide (CO) demonstrated the strongest associations with death among children aged <5 years at lag0, and the estimates decreased or even turned negative with the increasing lag periods. For an interquartile range increase in SO2, NO2 and CO at lag0, the odds ratios (OR) were 1.332 (95% CI 1.152-1.539), 1.383 (95% CI 1.113-1.718) and 1.273 (95% CI 1.028-1.575). However, CO lost significance after adjusting for SO2 and NO2, and PM2.5 gained significance (OR 1.548, 95% CI 1.061-2.258) after adjusting for PM10. The ORs for SO2 and NO2 remained the most stable across all two-pollutant models. The associations for children aged 1-5 years were stronger than those reported for infants at lag0 but lower at the other lag months. The pollutant associations were stronger for congenital heart disease-related death than overall and pneumonia-related death. We did not find significant differences in terms of gender. CONCLUSION: Exposure to air pollution may increase the incidence of death among children aged <5 years. SO2 and NO2 may be the most stable pollutants reflecting associations between air pollution and death, deserving further attention. Children with congenital heart diseases are more susceptible to air pollution. Therefore, it is urgent to implement the clean air targets established by WHO and reduce the exposure of children to air pollution.

Effect of polyvinylphosphonic acid on resin-dentin bonds and the cytotoxicity of mouse dental papilla cell-23.

STATEMENT OF PROBLEM: Polyvinylphosphonic acid (PVPA) could be used as a biomimetic remineralization analog and a matrix metalloproteinases (MMPs) inhibitor. However, studies are lacking regarding the performance of PVPA in dental bonding systems for maintaining the durability of the resin-dentin bond. PURPOSE: The purpose of this in vitro study was to investigate the effect of PVPA on the durability of resin-dentin bonds and the viability of mouse dental papilla cell-23 (MDPC-23). The mechanical properties of resin-dentin interfaces during long-term storage were analyzed, and the potential application of PVPA as a biomimetic remineralization analog in adhesive dentistry was evaluated. MATERIAL AND METHODS: Seventy-five extracted noncarious human third molars were collected and randomly divided into 5 groups, and then the microtensile bond strength (µTBS) data and scanning electron microscope (SEM) images were used to evaluate the preservation condition of resin-dentin bonds after 1 day, 6 months, and 1 year of storage. The cytotoxicity of PVPA was detected by cell proliferation assay and cell apoptosis assay. RESULTS: Compared with the control and chlorhexidine (CHX) groups, the combined group (treated with both 200-µg/mL PVPA and biomimetic remineralization) had excellent bond durability. The exposed collagen fibril from the PVPA-treated groups (included 200-µg/mL and 500-µg/mL PVPA groups and a combined group) still showed integrity after 1 year of storage when compared with the control group. PVPA up to 500 µg/mL showed no cytotoxicity to MDPC-23 and did not inhibit cell growth. CONCLUSIONS: This study offered evidence that PVPA did not result in cytotoxicity at low concentrations as an MMP inhibitor and a biomimetic remineralization analog. In addition, the application of PVPA improved bond strength and preserved collagen integrity after 1 year of in vitro storage.

Sequences analysis and pituitary actions of tachykinins in Chinese sturgeon (Acipenser sinensis).

Tachykinins belong to a large, evolutionarily conserved family of brain/gut peptides that are involved in a variety of physiological functions in mammals, such as reproductive regulation. However, little information was available about tachykinins in ancient fish lineage. In the present study, we firstly identified three tachykinin genes (named tac1, tac3 and tac4) and three neurokinin receptors (named nk1r, nk2r and nk3r) from Chinese sturgeon brain and pituitary. Sequence analysis showed that tac1 encoded substance P (SP) and neurokinin A (NKA), tac3 encoded neurokinin B (NKB) and NKB-related peptide (NKBRP), and tac4 encoded hemokin 1 (HK-1) and hemokin 2 (HK-2), respectively. The luciferase reporter assay results showed that NK1R preferentially selected asSP, NK2R preferentially selected asNKA, and NK3R preferentially selected asNKB. Tissue expression analysis showed that the three tac genes were highly detected in the telencephalon and hypothalamus, whereas nkr genes were widely expressed in peripheral tissues. Spatio-temporal expression analysis showed that all three tac genes were highly expressed in unknown sex individuals. Intraperitoneal injection experiments showed that both asSP and asNKB could stimulate luteinizing hormone (LH) release in Chinese sturgeon serum. At the transcriptional level, asSP and asNKB could significantly reduce pituitary follicle-stimulating hormone beta (fshß) mRNA expression, but induce pituitary growth hormone (gh) mRNA expression. In addition, estradiol (E2) could stimulate tac3 mRNA expression in hypothalamus. Taken together, this study provided information on the tachykinin family in Chinese sturgeon and demonstrates that asNKB and asSP could be involved in reproductive and growth regulation in pituitary.

Association of long-term exposure to air pollutant mixture and incident cardiovascular disease in a highly polluted region of China.

Despite growing evidence that links long-term air pollution exposure to cardiovascular disease (CVD), the combined effects of air pollutants and particulate matter with an aerodynamic diameter of less than 2.5 µm (PM2.5) components are still limited. A prospective cohort study was performed based on the Cohort Study on Chronic Disease of the Community Natural Population in the Beijing-Tianjin-Hebei Region (CHCN-BTH) to assess the association of long-term air pollutants with incident CVD and the combined effect of the air pollutants mixture among 26,851 adults. Three-year residential exposure to air pollutants (PM2.5, O3, PM10, PM1, NO2, SO2 and CO) and PM2.5 components [black carbon (BC), NH4+, SO42-, NO3- and organic matter (OM)] were calculated based on well-validated models. Proportional hazard models were applied to assess the association of air pollutants with incident CVD. Quantile g-Computation was used to examine the combined effect of the pollutant mixture. During the 56,090 person-years follow-up, 629 participants reported incident CVD. Adjusted hazard ratios with 95% confidence intervals (CIs) of CVD per interquartile range increase in O3, PM2.5, PM1, NO2, BC, and OM concentrations were 4.52 (95%CI: 2.61, 7.83), 2.39 (95%CI: 1.83, 3.13), 2.37 (95%CI: 1.20, 4.70), 1.36 (95%CI: 1.19, 1.56), 3.84 (95%CI: 2.38, 6.18), and 3.07 (95%CI: 2.01, 4.69), respectively. In multi-pollutant models, the combined effect of air pollutant mixture on incident CVD was 2.37 (95%CI: 2.30, 2.44). PM2.5 and O3 contributed 54.3% and 44.5% of the combined effect of the air pollutant mixture, respectively. After using PM2.5 components instead of PM2.5 as part of the mixture, OM drove 55.2% of the combined effect. The findings indicated associations of air pollutant mixtures with CVD incidence. PM2.5 (especially OM) and O3 might strongly contribute to air pollutant mixtures that lead to incident CVD.

Association of Serum Metabolites and Salt Sensitivity of Blood Pressure in Chinese Population: The EpiSS Study.

BACKGROUND: To identify novel metabolites associated with salt sensitivity of blood pressure (SSBP) in Chinese Han population. METHODS: A case-control study was conducted with 25 salt sensitive (SS) and 26 salt resistant (SR) participants, which was selected from the Systems Epidemiology Study on Salt Sensitivity of Blood Pressure (EpiSS) study. The modified Sullivan's acute oral saline load and diuresis shrinkage test (MSAOSL-DST) was conducted to identify SS. Untargeted, ultra-high performance liquid chromatograph-high resolution mass spectrometer (UPLC-HRMS) was conducted and orthogonal partial least squares-discriminate analysis (OPLS-DA) and multivariable logistic regression model were used to screen the metabolites related to SS, mixed linear regressions models were used to examined the association of SSBP with metabolites during saline load period and diuresis shrinkage period. Receiver operating characteristic (ROC) curve analysis was performed. The area under the curve's (AUC) sensitivity and specificity were calculated to identified metabolites biomarkers for SS. RESULTS: There were 39 differentially expressed metabolites (DE-metabolites) between SS and SR. Thirty-five and four of DE-metabolites were inversely or positively associated with SS, respectively. Four biochemical pathways demonstrated significant enrichment for identified metabolites. In single-metabolite analyses, L-Glutamine displayed the best diagnostic performance (AUC = 0.88, 95% CI: 0.78-0.97). In multi-metabolites analyses, L-Glutamine + Cholesterol ester 22:5n6 combination showed the best diagnostic performance (AUC = 0.96, 95% CI: 0.91-1.00). Adjusted for traditional risk factors, L-Glutamine and Cholesterol ester 22:5n6 explained an additional 38.3% of SS susceptibility. CONCLUSIONS: This study provide potential evidence for clarifying the mechanism of SS and provide novel biological insights into salt sensitive hypertension.

Associations between depressive, anxiety, stress symptoms and elevated blood pressure: Findings from the CHCN-BTH cohort study and a two-sample Mendelian randomization analysis.

BACKGROUND: We aimed to determine whether depressive, anxiety, stress symptoms were associated with the risk of elevated blood pressure by performing longitudinal cohort and Mendelian Randomization (MR) analyses. METHODS: We used data from the Cohort Study on Chronic Disease of Community Natural Population in the Beijing-Tianjin-Hebei region (CHCN-BTH) from 2017 to 2021. The Depression-Anxiety-Stress Scale was used to evaluate the depressive, anxiety, stress symptoms. The longitudinal associations between depressive, anxiety, stress symptoms and elevated blood pressure were estimated using Cox proportional regression models. Two-sample MR analysis was performed using the Inverse-variance weighted (IVW), weighted median, and MR-Egger to explore the causal relationships between depressive, anxiety, stress symptoms and elevated blood pressure. RESULTS: In total, 5624 participants were included. The risk of SBP ≥ 140 mmHg or DBP ≥ 90 mmHg was significantly higher in participants with baseline anxiety symptoms (HR = 1.48, 95 % CI: 1.03 to 2.12, P = 0.033; HR = 1.56, 95 % CI: 1.05 to 2.32, P = 0.028), especially in men and individuals with higher educational levels, independent of baseline depression and anxiety at the two-year follow-up. The two-sample MR analysis showed positive associations between depressive, anxiety, stress symptoms and elevated blood pressure. LIMITATION: Self-reported mental health symptoms, relatively shorter follow-up duration and the European-derived genome-wide association study data for MR analysis. CONCLUSIONS: Anxiety symptoms were positively associated with elevated blood pressures in the longitudinal analysis independent of depression, stress, and other confounders. The results were verified in MR analysis, providing evidence for causal effects of anxiety symptoms on the risk of elevated blood pressure.

Klotho enhances bone regenerative function of hPDLSCs via modulating immunoregulatory function and cell autophagy.

BACKGROUND: Human periodontal ligament stem cells (hPDLSCs) have a superior ability to promote the formation of new bones and achieve tissue regeneration. However, mesenchymal stem cells (MSCs) are placed in harsh environments after transplantation, and the hostile microenvironment reduces their stemness and hinders their therapeutic effects. Klotho is an antiaging protein that participates in the regulation of stress resistance. In our previous study, we demonstrated the protective ability of Klotho in hPDLSCs. METHODS: A cranial bone defect model of rats was constructed, and the hPDLSCs with or without Klotho pretreatment were transplanted into the defects. Histochemical staining and micro-computed tomography were used to detect cell survival, osteogenesis, and immunoregulatory effects of hPDLSCs after transplantation. The in vitro capacity of hPDLSCs was measured by a macrophage polarization test and the inflammatory level of macrophages. Furthermore, we explored autophagy activity in hPDLSCs, which may be affected by Klotho to regulate cell homeostasis. RESULTS: Pretreatment with the recombinant human Klotho protein improved cell survival after hPDLSC transplantation and enhanced their ability to promote bone regeneration. Furthermore, Klotho pretreatment can promote stem cell immunomodulatory effects in macrophages and modulate cell autophagy activity, in vivo and in vitro. CONCLUSION: These findings suggest that the Klotho protein protects hPDLSCs from stress after transplantation to maintain stem cell function via enhancing the immunomodulatory ability of hPDLSCs and inhibiting cell autophagy.