Fast and slow responses of surface air temperature in China to short-lived climate forcers.

Short-lived climate forcers (SLCFs), including aerosols, tropospheric ozone, and methane in this work, are attracting increasing attention because of their extensive impacts on regional climate and air pollution. To clarify the impact of controlling SLCFs in high-emission areas on regional surface air temperature (SAT), we quantified the SAT response in China due to both global and China's SLCF changes by using an aerosol-climate model. The average SAT response in China to global SLCF changes from 1850 to 2014 was -2.53 °C ± 0.52 °C, which was much stronger than the global mean SAT response (-1.85 °C ± 0.15 °C). There are two cooling centers in China, located in the northwest inland areas (NW) and southeastern areas (SE), with area mean SAT responses of -3.39 °C ± 0.70 °C and -2.43 °C ± 0.62 °C, respectively. Because the SE area has experienced greater changes in SLCFs concentrations, compared with the NW area, China's SLCFs contribute more to the SAT response in the SE (approximately 42 %) than to the SAT response in the NW (<25 %). We divided the SAT response into fast and slow components to investigate the underlying mechanisms. In the fast response, the strength of the regional SAT response was closely connected to changes in the SLCFs concentration. The prominent increase in SLCFs in the SE area reduced the surface net radiation flux (NRF), thereby decreasing the SAT by 0.44 °C ± 0.47 °C. The smaller increase in SLCFs in the NW area, compared with the SE area, resulted in a less reduction in NRF and a minor fast SAT response (-0.01 °C ± 0.76 °C). In the slow response, the SLCFs-induced increases of mid- and low-cloud cover significantly reduced the NRF, resulting in strong slow SAT responses of -3.38 °C ± 0.70 °C and -1.98 °C ± 0.62 °C in the NW and SE areas, respectively.

Deciphering the chromatin spatial organization landscapes during BMMSC differentiation.

The differentiation imbalance in bone marrow mesenchymal stem cells (BMMSCs) is critical for the development of bone density diseases as the population ages. BMMSCs are precursor cells for osteoblasts and adipocytes; however, the chromatin organization landscapes during BMMSC differentiation remain elusive. In this study, we systematically delineate the four-dimensional genome and dynamic epigenetic atlas of BMMSCs by RNA sequencing, assay for transposase-accessible chromatin sequencing, and high-throughput chromosome conformation capture. The structure analyses reveal 17.5% common and 28.5%-30% specific loops among BMMSCs, osteoblasts, and adipocytes. The subsequent correlation of genome-wide association studies and expression quantitative trait locus (eQTL) data with multi-omics analysis reveal 274 genes and 3634 single nucleotide polymorphisms (SNPs) associated with bone degeneration and osteoporosis (OP). We hypothesize that SNP mutations affect transcription factor (TF) binding sites, thereby affecting changes in gene expression. Furthermore, 26 motifs, 260 TFs, and 291 SNPs are identified to affect the eQTL. Among these genes, DAAM2, TIMP2, and TMEM241 are found to be essential for diseases such as bone degeneration and OP and may serve as potential drug targets.

A pooled analysis of the association between sarcopenia and osteoporosis.

BACKGROUND: Sarcopenia is a progressive generalized skeletal muscle disorder that causes the accelerated loss of muscle mass and function. Osteoporosis is a systemic condition of the skeleton that results in low bone mass and quality. Several studies have suggested that osteoporosis and sarcopenia are interrelated; however, a few studies indicate the lack of a significant association between sarcopenia and osteoporosis. We aimed to evaluate the association between sarcopenia and osteoporosis via a systematic review and pooled analysis. METHODS: From the inception of the PubMed and Embase databases until September 2022, we conducted a systematic search for studies evaluating the relationship between sarcopenia and osteoporosis. Study appraisal and synthesis methods: We included observational studies that provided 95% confidence intervals (CIs) and risk estimates. Two reviewers independently extracted data and assessed the quality of the research. The random-effects model was applied to the pool analysis, and the odds ratios (ORs) and 95% CIs were finally calculated. RESULTS: The primary statistic was the mutual risk between sarcopenia and osteoporosis. According to the inclusion criteria, 56 studies (796,914 participants) were finally included. Sarcopenia was significantly correlative to the risk of osteoporosis (OR, 3.06; 95% CI, 2.30-4.08), and each standard deviation increase in relative appendicular skeletal muscle mass was significantly related to a decreased risk of osteoporosis (OR, 0.65; 95% CI, 0.56-0.75). Osteoporosis observably referred to a higher risk of sarcopenia (OR, 2.63; 95% CI, 1.98-3.49). CONCLUSION: Our research indicated that sarcopenia and osteoporosis are highly positively correlated. Osteoporosis is closely associated with the risk of sarcopenia. Our finding highlights the importance of sarcopenia screening for those at risk of osteoporosis, and vice versa. However, heterogeneity was noted among the studies, and this might have influenced the accuracy of the results. Therefore, the results of our study should be interpreted with caution.

Effective Radiative Forcings Due To Anthropogenic Emission Changes Under Covid-19 and Post-Pandemic Recovery Scenarios.

With the continuation of the Coronavirus Disease 2019 (Covid-19) pandemic, the impacts of this catastrophe on anthropogenic emissions are no longer limited to its early stage. This study quantitatively estimates effective radiative forcings (ERFs) due to anthropogenic well-mixed greenhouse gases (WMGHGs) and aerosols for the period 2020-2050 under the three latest Covid-19 economic-recovery scenarios using an aerosol-climate model. The results indicate that reductions in both WMGHG and aerosol emissions under the Covid-19 green recoveries lead to increases ranging from 0 to 0.3 W m-2 in global annual mean anthropogenic ERF over the period 2020-2050 relative to the Shared Socioeconomic Pathway 2-4.5 scenario (the baseline case). These positive ERFs are mainly attributed to the rapid and dramatic decreases in atmospheric aerosol content that increase net shortwave radiative flux at the top of atmosphere via weakening the direct aerosol effect and low cloud cover. At the regional scale, reductions in aerosols contribute to positive ERFs throughout the Northern Hemisphere, while the decreased WMGHGs dominate negative ERFs over the areas away from aerosol pollution, such as the Southern Hemisphere oceans. This drives a strong interhemispheric contrast of ERFs. In contrast, the increased anthropogenic emissions under the fossil-fueled recovery scenario lead to an increase of 0.3 W m-2 in global annual mean ERF in 2050 compared with the baseline case, primarily due to the contribution of WMGHG ERFs. The regional ERF changes are highly dependent on local cloud radiative effects.

Identification of an unrecognized circRNA associated with development of renal fibrosis.

Backgroud: Renal fibrosis is the common characteristic of chronic kidney disease. Circular RNA plays an essential role in the occurrence and development of Renal fibrosis, but its regulative mechanism remains elusive. Methods: The animal and cell model of Renal fibrosis was established, and RNA-sequencing and real-time polymerase chain reaction (qRT-PCR) experiments were implemented. Subsequently, experiments for detecting apoptosis and proliferation of cell, were carried out, and the isobaric tags for relative and absolute quantification proteomics analyses were performed accordingly. Results: It was found that a newly discovered Circular RNA (circRNA_0002158), is highly expressed in kidneys or cells with fibrosis, implying that this Circular RNA might be associated with the occurrence and development of Renal fibrosis. Subsequently, the overexpression and knockdown of circRNA_0002158 were conducted in the human kidney epithelial cell line (HK-2) cells, and the results indicated that the circRNA_0002158 could inhibit apoptosis, and promote proliferation of cells. The kidney injury-related factors, including Fibronectin and plasminogen activator inhibitor-1 (PAI-1), were decreased in HK-2 cells with overexpression of circRNA_0002158, while the results were reversed in cells with knockdown of circRNA_0002158. Finally, to explore the regulative mechanism of circRNA_0002158, the iTRAQ proteomics analyses were implemented for the cell samples with OE of circRNA_0002158 and its control, it showed that multiple genes and functional pathways were associated with the occurrence and development of Renal fibrosis. Conclusion: CircRNA_0002158 is associated with regulating Renal fibrosis, and may contribute to ameliorating the progression of Renal fibrosis in the future.

Bioinformatics analyses of the pathogenesis and new biomarkers of chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the major cause of global death. The purpose of our analysis was to detect a more reliable biomarker and small-molecule drug candidates and to identify the precise mechanisms involved in COPD. METHODS: Three data sets were downloaded from the Gene Expression Omnibus database and analysed by Gene Expression Omnibus 2R. Functional enrichment analyses were performed by Metascape. We use the STRING data to build a protein-protein interaction network. The targets of differentially expressed microRNA (DE miRNA) were predicted by the miRWalk database. Small-molecule drugs were predicted on connectivity map. RESULTS: A total of 181 differentially expressed genes and 35 DE miRNAs were confirmed. The protein-protein interaction network including all integrated differentially expressed genes was constructed, and 4 modules were filtrated. The module genes were relative to immune, inflammatory and oxidative stress functions according to a pathway analysis. The top 20 key genes were screened. Among the DE miRNAs found to be regulating key genes, miR-194-3p, MiR-502-5p, MiR-5088-5p, MiR-3127-5p, and miR-23a-5p might be the most significant due to their high number of connecting nodes in COPD. In addition, cephaeline, emetine, gabapentin, and amrinone were found to be potential drugs to treat COPD patients. CONCLUSION: Our study suggests that miR-194-3p, miR-502-5p, and miR-23a-5p might participate in the nosogenesis of COPD. In addition, 4 potential small-molecule drugs were considered potentially useful for treating COPD patients.

Long non-coding RNA taurine upregulated gene 1 is downregulated in osteoporosis and influences the osteogenic differentiation of bone marrow mesenchymal stem cells.

BACKGROUND: With aging, an imbalance in bone remodeling leading to increased bone resorption and decreased bone formation is thought to contribute to osteoporosis. Osteoblastic differentiation of bone marrow mesenchymal stem cells (BMMSCs) plays a vital role in the pathogenesis of osteoporosis. However, the detailed molecular mechanisms of osteoporosis remain incompletely understood. Given that long non-coding RNA taurine upregulated gene 1 (lnc TUG1) plays a critical role in the osteogenic differentiation, and microRNA-23b (miR-23b) as a putative sponge for lnc TUG1 has upregulated expression in osteoporosis. Therefore, this study investigated the roles of TUG1/miR-23b in osteoporotic pathology. MATERIAL AND METHODS: TUG1 and miR-23b expression in the plasma of osteoporotic patients were evaluated by quantitative real-time PCR (qRT-PCR). The osteogenic differentiation in human BMMSCs was evaluated by qRT-PCR, western blot, Alizarin red staining after knockdown of TUG1 by small interfering RNA (siRNA) treatment. RESULTS: Decreased expression of TUG1 and increased expression of miR-23b evident in the plasma of patients with osteoporosis than in that of age- and sex-matched healthy controls. Additionally, increased miR-23b expression inhibited runt-related transcription factor 2 (RUNX2), osteocalcin, and osteopontin expression and reduced calcified nodule formation based on the results of qRT-PCR, western blot, and Alizarin Red S staining. CONCLUSION: The study for the first time reported that silence of lncRNA TUG1 significantly suppressed the osteogenic differentiation of BMMSCs possibly by targeting the miR-23b/RUNX2 signaling pathway. This mechanism of TUG1/miR-23b/RUNX2 signaling within the osteogenic differentiation of BMMSCs might provide new insight for the development of lncRNA-directed diagnostic and therapeutic strategies for osteoporosis.

An analysis and systematic review of sarcopenia increasing osteopenia risk.

Sarcopenia is a progressive generalized skeletal muscle disorder, which may increase the risk of osteopenia. The aim of this study was to systematically review studies on the association between sarcopenia and osteopenia by pooled analysis. The PubMed and Embase databases were searched from inception to October 2020 for studies focusing on the association between sarcopenia and osteopenia. Two reviewers independently extracted data and assessed study quality. A pooled analysis was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs) using random-effects models. Subgroup analysis was conducted to explore the source of heterogeneity and the stability of outcome. A total of 25 independent studies involving 47,744 participants fulfilled the inclusion criteria. Sarcopenia significantly increased the risk of osteopenia (OR, 2.08; 95% CI, 1.66-2.60); Sensitivity analyses indicated the outcome was stable. Subgroup analyses showed that sarcopenia significantly increased osteopenia risk in each subgroup. No evidence of publication bias among the studies existed. In this study, our findings showed that sarcopenia significantly increased the risk of osteopenia. Thus, we suggest that sarcopenia can be a predictor of osteopenia risk.

Photocatalytic performances of heterojunction catalysts of silver phosphate modified by PANI and Cr-doped SrTiO3 for organic pollutant removal from high salinity wastewater.

In this work, Ag3PO4/PANI/Cr:SrTiO3 photocatalysts were designed to effectively eliminate organic pollutants including Rhodamine B and phenol from high salinity wastewater under visible light. The phase composition, optical properties, and morphology of powders were studied, and the effects of inorganic salts on removal performance of the as-prepared particles were also tested. Results showed that the photocatalytic activities of Ag3PO4/PANI/Cr:SrTiO3 composites for Rhodamine B and phenol reached 100% within 10 min and 18 min, respectively. The reaction rate of pure Ag3PO4 was 7 times less than that of the ternary composite with the adding of PANI and Cr:SrTiO3. The activity of Ag3PO4/PANI/Cr:SrTiO3 remained at 92.25% after five cycles, so the photocatalytic and recyclable performance of ternary composite was greatly improved. In addition, when there was SO42- with a content of ranging from 1% to 21%, the degradation activity of the ternary catalyst under visible light was not changed for Rhodamine B, which indicated that the ternary catalyst exhibited the excellent sulfate resistance ability. Results from ESR and radical trapping experiments showed that O2- and h+ made an important contribution to visible-light photocatalytic activities.

Impacts of different types and intensities of El Niño events on winter aerosols over China.

El Niño is a strong signal of interannual climate variability. The occurrence of an El Niño event may have an important impact on atmospheric pollutant concentrations in China through changes to the regional climate. This study quantitatively examines the differences among the effects of different types and intensities of El Niño events on winter mean aerosol concentration and severe haze days in China. It is found that Central Pacific (CP) El Niño events lead to larger increases in the aerosol burden over southern China relative to the same intensity of Eastern Pacific (EP) events. For El Niño events of the same type but with different intensities, moderate events induce large increases in surface aerosol concentrations over the entire eastern China, while strong and weak events lead to obvious decreases in the surface aerosol concentration over northern China. These differences are mainly attributed to changes in atmospheric circulation, with the resulting changes in aerosol mass transport occurring in response to the different types of El Niño event. Except for moderate CP events, all kinds of El Niño events lead to an increase in severe haze days in winter over northern China. Strong and weak EP El Niño events and weak CP El Niño events lead to an increase in severe haze days in winter over southern China. A change in the south-north transport of aerosols caused by El Niño events also play a dominate role in changing the occurrence of winter haze days in China.