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1.
Curr Med Sci ; 41(2): 199-210, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33877536

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) in indoor dust are one of the common exposure sources for children worldwide. The aim of this study is to explore PAHs pollution status in indoor dust and estimate health risk on Chinese children with big data. Weighted average concentration was used to analyze source and characterization of PAHs in indoor dust based on peer-reviewed literature. According to specific inclusion criteria, 17 studies were included finally to analyze weighted average concentration. The national average concentration of Σ16PAHs was approximately 25.696 µg/g. The highest concentration of Σ16PAHs was in Shanxi (2111.667 µg/g), and the lowest was in Hong Kong (1.505 µg/g). The concentrations in Shanxi and Guangdong were higher than national level and the over standard rate was 18.18%. The concentrations of individual PAHs varied greatly across the country, and Flu in Shanxi was the highest (189.400 µg/g). The sources of PAHs varied in different regions and combustion processes played a leading role. PAHs exposure through ingestion and dermal contact was more carcinogenic than inhalation. The incremental lifetime cancer risk model indicated that children lived in Shanxi were found in the highest health risk coupled with the highest BaPE concentration (54.074 µg/g). Although PAHs concentrations of indoor dust showed a downward trend from 2005 to 2018, indoor environmental sanitation should be improved with multidisciplinary efforts. Health standard should be possibly established to minimize children exposure to PAHs in indoor dust in China.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33876551

RESUMO

The first all-amidinate-protected gold nanocluster [Au28(Ph-form)12](OTf)2 (Ph-form = N,N'-Diphenylformamidine) ( Au28 ) has been synthesized and structurally resolved. Single crystal X-ray diffraction reveals that Au28 has a compact Au4@Au24 tetrahedral core-shell structure of T symmetry, which is fully protected by 12 bridging formamidinate ligands. This cluster is quite robust as indicated by the fact that it can stay intact in solution at 80 °C for 6 d. It exhibits excellent catalytic performance for the electroreduction of CO2 with 96.5% Faradaic efficiency (FE) at -0.57 V and a maximum TOF of 48492 h-1 at -0.87 V. Its superior stability is also manifested in the fact that the supported catalyst Au28/CNTs maintains stable potentials at ca. -0.69 V for 40 h with FE(CO)s >91%. A superatomic electron configuration of 1S21P62S21D4 has been clarified by DFT computations, and the strong gold-ligand binding and geometric shell closure account for the superior stability of Au28 .

3.
ACS Appl Mater Interfaces ; 13(15): 17835-17843, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33826311

RESUMO

Heavy-metal contamination of water is a global problem with an especially severe impact in countries with old or poorly maintained infrastructure for potable water. An increasingly popular solution for ensuring clean and safe drinking water in homes is the use of adsorption-based water filters, given their affordability, efficacy, and simplicity. Herein, we report the preparation and functional validation of a new adsorbent for home water filters, based on our metal-organic framework (MOF) composite containing UiO-66 and cerium(IV) oxide (CeO2) nanoparticles. We began by preparing CeO2@UiO-66 microbeads and then encapsulating them in porous polyethersulfone (PES) granules to obtain millimeter-scale CeO2@UiO-66@PES granules. Next, we validated these granules as an adsorbent for the removal of metals from water by substituting them for the standard adsorbent (ion-exchange resin spheres) inside a commercially available water pitcher from Brita. We assessed their performance according to the American National Standards Institute (ANSI) guideline 53-2019, "Drinking Water Treatment Units-Health Effects Standard". Remarkably, a pitcher loaded with a combination of our CeO2@UiO-66@PES granules and activated carbon at standard ratios met the target reduction thresholds set by NSF/ANSI 53-2019 for all the metals tested: As(III), As(V), Cd(II), Cr(III), Cr(VI), Cu(II), Hg(II), and Pb(II). Throughout the test, the modified pitcher proved to be robust and stable. We are confident that our findings will bring MOF-based adsorbents one step closer to real-world use.

4.
Ann Palliat Med ; 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33832294

RESUMO

BACKGROUND: Since the coronavirus disease 2019 (COVID-19) emerged in Wuhan, China, it has become a global public health emergency. Besides conventional care, pulmonary rehabilitation (PR) is an equally important treatment for patients with COVID-19 suffering from respiratory, physical and psychological disease. The aim of this study is to investigate the role of PR on the inpatients with severe COVID-19. METHODS: This study was a self-pre- and post-control prospective clinical trial, which totally recruited 31 inpatients confirmed COVID-19 by RT-PCR. They were performed 3-weeks PR. The demographic data, medical records, symptoms, laboratory findings and chest computed tomographic (CT) scans of patients were collected at baseline. The effect of PR was assessed by questionnaires before PR as well as after 2- and 3-weeks PR. RESULTS: After 3-weeks PR and treatment, neutrophil percentage decreased, while lymphocyte percentage and lymphocyte count increased (before vs. 2 weeks after PR respectively: P=0.001; P=0.001; P<0.0001). Besides, CRP and procalcitonin reduced significantly (before vs. after respectively: P<0.0001; P=0.023). Patients' oxygen intake decreased and oxygen saturation increased significantly. Meanwhile, PR relieved the patients' symptoms of cough and dyspnea, improved the patients' self-care ability, physical fitness and mental state significantly. Activities of daily living (ADL) score increased and Modified Medical Research Council Dyspnea Scale (mMRC) decreased after PR. CONCLUSIONS: PR can relieve symptoms, enhance health-related quality of life, improve respiratory muscle function and alleviate disease-related anxiety and depression of severe patients with COVID-19. PR should be provided throughout the diseases management process, regardless of whether the patient is hospitalized or at home.

5.
BMC Cancer ; 21(1): 374, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827468

RESUMO

BACKGROUND: Flap endonuclease 1 (FEN1) is a structure-specific nuclease that plays a role in a variety of DNA metabolism processes. FEN1 is important for maintaining genomic stability and regulating cell growth and development. It is associated with the occurrence and development of several diseases, especially cancers. There is a lack of systematic bibliometric analyses focusing on research trends and knowledge structures related to FEN1. PURPOSE: To analyze hotspots, the current state and research frontiers performed for FEN1 over the past 15 years. METHODS: Publications were retrieved from the Web of Science Core Collection (WoSCC) database, analyzing publication dates ranging from 2005 to 2019. VOSviewer1.6.15 and Citespace5.7 R1 were used to perform a bibliometric analysis in terms of countries, institutions, authors, journals and research areas related to FEN1. A total of 421 publications were included in this analysis. RESULTS: Our findings indicated that FEN1 has received more attention and interest from researchers in the past 15 years. Institutes in the United States, specifically the Beckman Research Institute of City of Hope published the most research related to FEN1. Shen BH, Zheng L and Bambara Ra were the most active researchers investigating this endonuclease and most of this research was published in the Journal of Biological Chemistry. The main scientific areas of FEN1 were related to biochemistry, molecular biology, cell biology, genetics and oncology. Research hotspots included biological activities, DNA metabolism mechanisms, protein-protein interactions and gene mutations. Research frontiers included oxidative stress, phosphorylation and tumor progression and treatment. CONCLUSION: This bibliometric study may aid researchers in the understanding of the knowledge base and research frontiers associated with FEN1. In addition, emerging hotspots for research can be used as the subjects of future studies.

6.
Med Phys ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33905539

RESUMO

PURPOSE: Accurate deformable registration between computed tomography (CT) and cone-beam CT (CBCT) images of pancreatic cancer patients treated with high biologically effective radiation doses is essential to assess changes in organ-at-risk (OAR) locations and shapes and to compute delivered dose. This study describes the development and evaluation of a deep-learning (DL) registration model to predict OAR segmentations on the CBCT derived from segmentations on the planning CT. METHODS: The DL model is trained with CT-CBCT image pairs of the same patient, on which OAR segmentations of the small bowel, stomach and duodenum have been manually drawn. A transformation map is obtained, which serves to warp the CT image and segmentations. In addition to a regularity loss and an image similarity loss, an OAR segmentation similarity loss is also used during training, which penalizes the mismatch between warped CT segmentations and manually drawn CBCT segmentations. At test time, CBCT segmentations are not required as they are instead obtained from the warped CT segmentations. In an IRB-approved retrospective study, a dataset consisting of 40 patients, each with 1 planning CT and 2 CBCT scans, was used in a 5-fold cross-validation to train and evaluate the model, using physician-drawn segmentations as reference. Images were preprocessed to remove gas pockets. Network performance was compared to two intensity-based deformable registration algorithms (large deformation diffeomorphic metric mapping [LDDMM] and multi-modality free-form [MMFF]) as baseline. Evaluated metrics were Dice similarity coefficient (DSC), change in OAR volume within a volume of interest (enclosing the low-dose PTV plus 1 cm margin) from planning CT to CBCT, and maximum dose to 5 cm3 of the OAR [D(5cc)]. RESULTS: Processing time for one CT-CBCT registration with the DL model at test time was less than 5 s on a GPU-based system, compared to an average of 30 min for LDDMM optimization. For both small bowel and stomach/duodenum, the DL model yielded larger median DSC and smaller interquartile variation than either MMFF (paired t-test p< 10-4 for both type of OARs) or LDDMM (p< 10-3 and p=0.03, respectively). Root-mean-square deviation (RMSD) of DL-predicted change in small bowel volume relative to reference was 22% less than for MMFF (p = 0.007). RMSD of DL-predicted stomach/duodenum volume change was 28% less than for LDDMM (p = 0.0001). RMSD of DL-predicted D(5cc) in small bowel was 39% less than for MMFF (p = 0.001); in stomach/duodenum, RMSD of DL-predicted D(5cc) was 18% less than for LDDMM (p < 10-3 ). CONCLUSIONS: The proposed deep network CT-to-CBCT deformable registration model shows improved segmentation accuracy compared to intensity-based algorithms and achieves an order-of-magnitude reduction in processing time.

7.
Dalton Trans ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33908517

RESUMO

Transition metal selenides have attracted enormous research attention as anodes for lithium-ion batteries (LIBs) due to their high theoretical specific capacities. Nevertheless, the low electronic conductivity and dramatic volume variation in electrochemical reaction processes result in rapid capacity fading and poor rate capability. Herein, a metal-organic framework is used as a template to in situ synthesize Sb2Se3 nanoparticles encapsulated in N-doped carbon nanotubes (N-CNTs) grafted on reduced graphene oxide (rGO) nanosheets. The synergistic effects of N-doped carbon nanotubes and reduced graphene oxide nanosheets are beneficial for providing good electrical conductivity and maintaining the structural stability of electrode materials, leading to stable cycling performance and superior rate performance. Kinetic analysis suggests that the electrochemical reaction kinetics is dominated by pseudocapacitive contribution. Notably, a high discharge capacity of 451.1 mA h g-1 at a current density of 2.0 A g-1 is delivered after 450 cycles. Even at a high current density of 10.0 A g-1, a discharge capacity of 192.6 mA h g-1 is maintained after 10 000 cycles. When coupled with a commercial LiFePO4 cathode, the full batteries show an excellent discharge specific capacity of 534.5 mA h g-1 at 0.2 A g-1. This work provides an effective strategy for constructing high-performance anodes for Li+ storage.

8.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668763

RESUMO

A subpopulation of mesenchymal stem cells, developmentally derived from multipotent neural crest cells that form multiple facial tissues, resides within the dental pulp of human teeth. These stem cells show high proliferative capacity in vitro and are multipotent, including adipogenic, myogenic, osteogenic, chondrogenic, and neurogenic potential. Teeth containing viable cells are harvested via minimally invasive procedures, based on various clinical diagnoses, but then usually discarded as medical waste, indicating the relatively low ethical considerations to reuse these cells for medical applications. Previous studies have demonstrated that stem cells derived from healthy subjects are an excellent source for cell-based medicine, tissue regeneration, and bioengineering. Furthermore, stem cells donated by patients affected by genetic disorders can serve as in vitro models of disease-specific genetic variants, indicating additional applications of these stem cells with high plasticity. This review discusses the benefits, limitations, and perspectives of patient-derived dental pulp stem cells as alternatives that may complement other excellent, yet incomplete stem cell models, such as induced pluripotent stem cells, together with our recent data.


Assuntos
Polpa Dentária/citologia , Doenças Genéticas Inatas/patologia , Células-Tronco Mesenquimais/citologia , Modelos Biológicos , Diferenciação Celular , Humanos
9.
Cell Stem Cell ; 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33711283

RESUMO

Impaired ribosome function is the underlying etiology in a group of bone marrow failure syndromes called ribosomopathies. However, how ribosomes are regulated remains poorly understood, as are approaches to restore hematopoietic stem cell (HSC) function loss because of defective ribosome biogenesis. Here we reveal a role of the E3 ubiquitin ligase HectD1 in regulating HSC function via ribosome assembly and protein translation. Hectd1-deficient HSCs exhibit a striking defect in transplantation ability and ex vivo maintenance concomitant with reduced protein synthesis and growth rate under stress conditions. Mechanistically, HectD1 ubiquitinates and degrades ZNF622, an assembly factor for the ribosomal 60S subunit. Hectd1 loss leads to accumulation of ZNF622 and the anti-association factor eIF6 on 60S, resulting in 60S/40S joining defects. Importantly, Znf622 depletion in Hectd1-deficient HSCs restored ribosomal subunit joining, protein synthesis, and HSC reconstitution capacity. These findings highlight the importance of ubiquitin-coordinated ribosome assembly in HSC regeneration.

10.
Phys Chem Chem Phys ; 23(11): 6888-6895, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33729229

RESUMO

Combining reinforcement learning (RL) and molecular dynamics (MD) simulations, we propose a machine-learning approach, called RL‡, to automatically unravel chemical reaction mechanisms. In RL‡, locating the transition state of a chemical reaction is formulated as a game, and two functions are optimized, one for value estimation and the other for policy making, to iteratively improve our chance of winning this game. Both functions can be approximated by deep neural networks. By virtue of RL‡, one can directly interpret the reaction mechanism according to the value function. Meanwhile, the policy function allows efficient sampling of the transition path ensemble, which can be further used to analyze reaction dynamics and kinetics. Through multiple experiments, we show that RL‡ can be trained tabula rasa hence allowing us to reveal chemical reaction mechanisms with minimal subjective biases.

11.
Biomed Pharmacother ; 137: 111325, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33761593

RESUMO

Pueraria, a Chinese herbal medicine, plays an important role in many classic prescriptions for the treatment of diabetes. Puerarin is the main component of pueraria. The current in vivo and in vitro research mainly focus on exploring the potential mechanism of puerarin in inhibiting hepatic gluconeogenesis. The type 2 diabetic rats were established by a combination of small dosage of streptozotocin (STZ) injection with high-fat diet. After the administration of puerarin 4 weeks, the parameters of the glucose and lipid metabolism were determined. HepG2 cells were treated by palmitic acid (PA) to induce the insulin resistance in vitro model. After the treatment of puerarin, the glucose consumption and cell viability were examined. Then, the protein expression of PI3K, Akt, pAkt, pFOXO1, FOXO1, PEPCK and G6pase in liver tissue and HepG2 cells were evaluated by western blot. RT-PCR was used to measure the content of PEPCK, G6pase mRNA in liver tissue. The results showed that puerarin administration significantly decrease the level of FBG, HbA1C and triglycerides in diabetic rats. Mechanistic research showed that puerarin activating PI3K/Akt is puerarin-mediated beneficial effects and can be reversed by inhibitor of PI3K or Akt. In conclusion, puerarin inhibits hepatic gluconeogenesis by activating PI3K/Akt signaling pathway.

12.
Sci Total Environ ; 778: 146221, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33721654

RESUMO

Coal mining activities have caused severe disturbances to the regional ecosystem and soil properties. Studying the relationship of vegetation and its below-ground habitat (RVBGH) is of great significance to the coal mine land ecological restoration. To identify the optimal thickness of the soil layer for mine land ecosystem recovery and characterize the changes of the reclaimed soil-vegetation ecosystem, we studied natural and reclaimed grassland at the coal mine of Baorixile, located in Hulunbuir Steppe, Northeastern China. The vegetation and its below-ground habitat (BGH), including "root mass" and soil properties in the soil profile (0-100 cm), were surveyed in the natural and different year-reclaimed grassland. The "root mass" is the part of root system that has the most amounts of root hairs, which is the functional zone for plant growth. The RVBGH was identified by the "root mass" and plant water extraction depth, measured through the isotope δD and δ18O method. Firstly, the BGH of natural grassland was identified as a "double layer" vertical structure, with the "root mass" of 37.11 ± 2.57% fine roots at 0-20 cm range and 30.44 ± 2.67% at 20-40 cm range. The annual and perennial plant "root mass" was found at 0-20 cm and 20-40 cm depth, respectively. Secondly, an optimal thickness of the soil covering of 30-40 cm was proposed for grassland reclamation. Thirdly, along the reclamation chronosequence, the values of the reclaimed vegetation properties (height, density, coverage and diversity) increased and a deep root system was established. The "root mass" increased from one layer to double layer and the amount of total fine roots increased from 1621 ± 231.9 to 4459 ± 456.0. Moreover, the reclaimed soil properties of organic matter, cation exchange capacity, available N and P also increased. The study proposed that vegetation restoration was significantly correlated with its BGH, suggesting that vegetation BGH recovery is crucial in ecological restoration.

13.
Sex Med ; 9(2): 100321, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33684795

RESUMO

INTRODUCTION: Treatments for Peyronie's disease (PD) include surgical management and collagenase clostridium histolyticum (CCH). AIMS: To evaluate PD treatment trends after CCH approval and compare clinical outcomes in CCH- and surgery-treated cohorts. METHODS: Patients newly diagnosed with PD between January 2011 and December 2017 were identified in a U.S. claims database. Cohorts initiating treatment with CCH or surgery between January 2014 and June 2017 were included. Patients were continuously enrolled ≥6 months before and ≥12 months after index date. Post-treatment penile complications and analgesic use were compared 1 year after procedure in propensity score-matched cohorts. MAIN OUTCOME MEASURES: The main outcome measures of this study were treatment patterns, penile complications, and analgesic use. RESULTS: In the newly diagnosed PD cohort, 1,609 patients received CCH and 1,555 patients had surgery. Overall CCH or surgery treatment rate/year increased from 9.8% in 2014 to 15.5% in 2017, with <1% receiving verapamil or interferon. Initial treatment ratios of CCH to surgery increased from approximately 1:1 (2014) to 2:1 (2017). In the unmatched CCH (n = 1,227) and surgery (n = 620) cohorts, more (P < .05) surgery-treated patients received analgesics (particularly opioids), oral PD therapies, vacuum erection devices, and phosphodiesterase-5 inhibitors before the index date. After propensity score matching (n = 620/cohort), newly occurring postprocedural complications during the follow-up period were higher in the surgery cohort (25.3% vs 18.4%, P = .003). The surgery cohort had significantly (P < .05) higher rates of erectile dysfunction (65.0% vs 44.8%), penile pain (17.9% vs 8.9%), and penile swelling (8.1% vs 5.2%) and was more likely to be prescribed opioids (93.3% vs 38.9%; P < .0001) or non-steroidal anti-inflammatory drugs (27.0% vs 20.3%; P = .006). CONCLUSION: CCH demonstrated fewer complications and less analgesic use than surgery and was used as the initial therapy for PD twice as often as surgery. L Trost, H Huang, X Han, et al. Treatment Patterns and Healthcare Outcomes with Collagenase Clostridium Histolyticum vs Surgery in Peyronie's Disease: A Retrospective Claims Database Analysis. Sex Med 2021;XX:XXX-XXX.

14.
J Oleo Sci ; 70(4): 531-540, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33692237

RESUMO

In this study, Novozym 435-catalyzed interesterification of ethyl ferulate (EF) with phosphatidylcholine (PC) in a two-phase system consisting of an ionic liquid (IL) and toluene was optimized to prepare feruloylated lysophospholipids (FLPs). Optimum conditions for the interesterification process were found to be [Bmim][Tf2N]/toluene ratio of 1:1 (v/v), solvent volume of 4 mL, molecular sieves (4 Å) concentration of 80 mg/mL, reaction temperature of 55°C, substrate molar ratio of 5:1 (PC/EF), Novozym 435 concentration of 50 mg/mL. Under these conditions, two FLPs products (1-FLP and 2-FLP) with total conversion rate of 50.79% were obtained. Because the formation of 1-FLP was significantly higher than 2-FLP, 1-FLP was purified and characterized by LC-MS and NMR. In addition, 1-FLP showed DPPH scavenging activity comparable with those of EF and BHT. Therefore, this study provides a good method for transformation of ferulic acid to improve its solubility and promote its application as functional ingredient in the food and pharmaceutical industries.

15.
Zhongguo Zhong Yao Za Zhi ; 46(2): 388-390, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645126

RESUMO

Two phloroglucinol compounds(1-2) were isolated and purified from 95% ethanol extract of Dryopteris fragrans through various column chromatographies on silica gel, Sephadex LH-20, medium pressure column chromatography, and preparative HPLC. Their structures were elucidated as 2',4',6'-trihydroxy-5'-methyl acetate-3'-methyl-1'-butyrophenone(1) and aspidinol B(2) based on their chemical and physicochemical methods and spectroscopic data. Compound 1 is a new phloroglucinol compound named "dryofraginol".


Assuntos
Dryopteris , Cromatografia Líquida de Alta Pressão , Etanol , Floroglucinol , Extratos Vegetais
16.
Brain Behav ; : e02108, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33742562

RESUMO

BACKGROUND: Several studies have demonstrated that coronary heart disease (CHD) is a high risk factor for cognitive impairment, whereas other studies showed that there was no association between cognitive impairment and CHD. The relationship between CHD and cognitive impairment is still unclear based on these conflicting results. Thus, it is of importance to evaluate the association between CHD and cognitive impairment. The present study made a meta-analysis to explore the association between CHD and risk of cognitive impairment. METHODS: Articles exploring the association between CHD and cognitive impairment and published before November 2020 were searched in the following databases: PubMed, Web of Science, Medline, EMBASE, and Google Scholar. We used STATA 12.0 software to compute the relative risks (RRs), odds ratios (ORs), or hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: The meta-analysis showed a positive association between CHD and risk of all-cause cognitive impairment with a random effects model (RR = 1.27, 95% CI 1.18 to 1.36, I2  = 82.8%, p < .001). Additionally, the study showed a positive association between myocardial infraction (MI) and risk of all-cause cognitive impairment with a random effects model (RR = 1.49, 95% CI 1.20 to 1.84, I2  = 76.0%, p < .001). However, no significant association was detected between angina pectoris (AP) and risk of all-cause cognitive impairment with a random effects model (RR = 1.23, 95% CI 0.95 to 1.58, I2  = 79.1%, p < .001). Subgroup studies also showed that CHD patients are at higher risk for vascular dementia (VD), but not Alzheimer's disease (AD) (VD: RR = 1.34, 95% CI: 1.28-1.39; AD: RR = 0.99, 95% CI: 0.92-1.07). CONCLUSION: In a word, CHD was significantly associated with an increased risk of developing cognitive impairment.

17.
Nutr Metab Cardiovasc Dis ; 31(5): 1401-1409, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33744040

RESUMO

BACKGROUND AND AIM: Longitudinal evidence on change in serum (SUA) with risk of cardiovascular disease (CVD) and all-cause mortality is limited, as many prior studies focused on baseline SUA. Further, the optimal threshold range of SUA change is unclear. METHODS AND RESULTS: A total of 63,127 participants without history of CVD were enrolled. Change in SUA was determined by the difference of SUA levels between 2006 and 2010, which divided by baseline SUA was percent change in SUA. Multivariable Cox proportional hazards models were used to calculated the hazard ratios (HRs) and 95% confidence intervals (CIs). Our analysis also included restricted cubic spline model and three-piecewise Cox proportion hazards model to address the non-linearity between percent change in SUA and outcomes. During a median follow-up of 7.04 years, 3341 CVD and 3238 deaths occurred. We did not observed a significant association between changes in SUA and CVD. However, changes in SUA at extreme were associated with higher risk of all-cause mortality, the HRs (95% CIs) were 1.15 (1.02-1.29) and 1.20 (1.06-1.35) in the first and fifth quintile group, compared with the third quintile group. We further found a U-shaped association between percent change in SUA and all-cause mortality, and the optimal range was within 20%. CONCLUSIONS: Changes in SUA at extreme were risk factors for all-cause mortality, but not for CVD in the general population. The findings are relevant for role of SUA in the management of CVD risk and may contribute to improve identification of patients at higher risk.

18.
Int J Phytoremediation ; : 1-11, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33682536

RESUMO

How arbuscular mycorrhizal (AM) fungi affect litter nutrient release and soil properties in the nutrient-deficient karst soil, is unclear. An experiment was conducted in this study using a dual compartment device composed of a planting compartment (for the Cinnamomum camphora seedlings with or without Funneliformis mosseae fungus) and a litter compartment (with or without the litter of Arthraxon hispidus). The center baffle between the compartments was covered with a double layer of 20-µm or 0.45-µm nylon mesh, which controlled the entrance of AM mycelium into the litter compartment. The results are as follows: AM mycelium significantly increased the mass loss and carbon and nitrogen releases and decreased the nitrogen concentration in the litter. AM mycelium could significantly increase soil organic carbon, total nitrogen and availability of phosphorus during litter decomposition in the litter compartment. Redundancy analysis showed that the effect of AM mycelium on the soil organic carbon, total nitrogen in the litter compartment was closely associated with the increase in carbon and nitrogen release from litter. It was concluded that AM mycelium can enhance litter decomposition and nutrient releases, contributing to greater nutrient input to the soil and then subsequently higher soil organic carbon and nutrient content in the nutrient-poor karst soils. STATEMENT OF NOVELTYThis study firstly estimated the impacts of arbuscular mycorrhizal fungi on litter nutrient releases and soil properties through root external mycelium.

19.
ACS Nano ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33645986

RESUMO

Cu2-xS has become one of the most promising thermoelectric materials for application in the middle-high temperature range. Its advantages include the abundance, low cost, and safety of its elements and a high performance at relatively elevated temperatures. However, stability issues limit its operation current and temperature, thus calling for the optimization of the material performance in the middle temperature range. Here, we present a synthetic protocol for large scale production of covellite CuS nanoparticles at ambient temperature and atmosphere, and using water as a solvent. The crystal phase and stoichiometry of the particles are afterward tuned through an annealing process at a moderate temperature under inert or reducing atmosphere. While annealing under argon results in Cu1.8S nanopowder with a rhombohedral crystal phase, annealing in an atmosphere containing hydrogen leads to tetragonal Cu1.96S. High temperature X-ray diffraction analysis shows the material annealed in argon to transform to the cubic phase at ca. 400 K, while the material annealed in the presence of hydrogen undergoes two phase transitions, first to hexagonal and then to the cubic structure. The annealing atmosphere, temperature, and time allow adjustment of the density of copper vacancies and thus tuning of the charge carrier concentration and material transport properties. In this direction, the material annealed under Ar is characterized by higher electrical conductivities but lower Seebeck coefficients than the material annealed in the presence of hydrogen. By optimizing the charge carrier concentration through the annealing time, Cu2-xS with record figures of merit in the middle temperature range, up to 1.41 at 710 K, is obtained. We finally demonstrate that this strategy, based on a low-cost and scalable solution synthesis process, is also suitable for the production of high performance Cu2-xS layers using high throughput and cost-effective printing technologies.

20.
J Neurosci ; 41(12): 2566-2580, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33536197

RESUMO

We show for the first time that the neuropeptide orexin modulates pupillary light response, a non-image-forming visual function, in mice of either sex. Intravitreal injection of the orexin receptor (OXR) antagonist TCS1102 and orexin-A reduced and enhanced pupillary constriction in response to light, respectively. Orexin-A activated OX1Rs on M2-type intrinsically photosensitive retinal ganglion cells (M2 cells), and caused membrane depolarization of these cells by modulating inward rectifier potassium channels and nonselective cation channels, thus resulting in an increase in intrinsic excitability. The increased intrinsic excitability could account for the orexin-A-evoked increase in spontaneous discharges and light-induced spiking rates of M2 cells, leading to an intensification of pupillary constriction. Orexin-A did not alter the light response of M1 cells, which could be because of no or weak expression of OX1Rs on them, as revealed by RNAscope in situ hybridization. In sum, orexin-A is likely to decrease the pupil size of mice by influencing M2 cells, thereby improving visual performance in awake mice via enhancing the focal depth of the eye's refractive system.SIGNIFICANCE STATEMENT This study reveals the role of the neuropeptide orexin in mouse pupillary light response, a non-image-forming visual function. Intravitreal orexin-A administration intensifies light-induced pupillary constriction via increasing the excitability of M2 intrinsically photosensitive retinal ganglion cells by activating the orexin receptor subtype OX1R. Modulation of inward rectifier potassium channels and nonselective cation channels were both involved in the ionic mechanisms underlying such intensification. Orexin could improve visual performance in awake mice by reducing the pupil size and thereby enhancing the focal depth of the eye's refractive system.

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