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1.
Nucleic Acids Res ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32009146

RESUMO

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.

2.
J Food Sci ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32078749

RESUMO

Peanut sprouts are a functional food material rich in phytochemicals, including trans-resveratrol. This study aimed to optimize the recovery of trans-resveratrol from peanut sprouts using a combination of peanut varieties and sawdust medium through accelerated solvent extraction (ASE) and the response surface method (RSM). We also aimed to determine the antioxidant activity of this trans-resveratrol extract. Optimal fermentation periods of sawdust and peanut variety for cultivating peanut sprouts were determined on the basis of trans-resveratrol content via high-performance liquid chromatography. The extraction variables temperature, static time, and ethanol concentration were used to create a 20-sample set fit to a second-order polynomial equation through multiple regression analysis (R2 = 0.8787, P < 0.01). Trans-resveratrol content (19.62 ± 2.33 µg/g) peaked in the Palgwang variety cultured in sawdust medium fermented for 45 days. Optimal conditions for ASE were determined regarding the extraction temperature (90.29 °C), static time (3.95 min), and solvent (81.54% EtOH/water), and the predicted trans-resveratrol content under optimal conditions was 30.23 µg/g. Sawdust medium was more effective in increasing the trans-resveratrol content than conventional hydroponics, and the optimized process of combining fermented sawdust cultivation for harvesting peanut sprouts with ASE has potential as an efficient method of obtaining mass quantities of trans-resveratrol from peanut sprouts with improved nutritional and functional properties. PRACTICAL APPLICATION: This study showed that sawdust medium is more effective than hydroponics in increasing the trans-resveratrol content in peanut sprouts. The recovery of trans-resveratrol from peanut sprouts and its antioxidant activity were optimized via accelerated solvent extraction (ASE) and the response surface methodology (RSM). The optimized process of combining fermented sawdust cultivation for harvesting peanut sprouts with ASE potentially provides an efficient method to obtain mass quantities of trans-resveratrol from peanut sprouts with improved nutritional and functional properties.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32069792

RESUMO

Hospital sewage plays a key role in the dissemination of antibiotic-resistant genes (ARGs) by serving as an environmental antimicrobial resistance reservoir. In this study, we aimed to characterize the cephalosporin- and carbapenem-resistant isolates from hospital sewage and receiving rivers. The results showed that ESBL (blaCTX-M) and carbapenemase genes (blaNDM and blaKPC) were widely detected in a number of different bacterial species. These resistance genes were mainly harbored in Enterobacteriaceae, followed by Acinetobacter and Aeromonas isolates. More attention should be given to these bacteria as important vectors of ARGs in the environment. Furthermore, we showed that the multidrug resistance phenotype was highly prevalent, which was found in 85.5% Enterobacteriaceae and 75% Acinetobacter strains. Notably, the presence of carbapenemase genes in isolates from treated effluents and receiving rivers indicates that the discharges of wastewater treatment plants could be an important source for high-risk resistance genes propagation to the environment. In conclusion, this study shows a high prevalence of ESBL- and carbapenemase-producing bacteria in hospital sewage and receiving rivers in China. These findings have serious implications for human health, and also suggest the need for more efforts to control the dissemination of resistant bacteria from hospital sewage into the environment.

4.
Redox Biol ; : 101459, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32086008

RESUMO

Phosphatidylinositol-3,4,5-trisphosphate [PI(3,4,5)P3] is a phosphorylated derivative of phosphatidylinositol 4-phosphate [PI(4)P] and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], which recruit and activate AKT in the plasma membrane (PM) to promote cellular survival. ORP5 anchors at the endoplasmic reticulum (ER)-PM contact sites and acts as a PI(4)P and PI(4,5)P2/phosphatidylserine (PS) exchanger. Here, a lipidomics analysis of the sensorimotor cortex revealed that transient middle cerebral artery occlusion (tMCAO) disturbs the homeostasis of phosphatidylinositols (PIs) and PS between the PM and ER. Conditional knockout mice showed that ORP5 contributes to this abnormal distribution. Abolishing the ORP5 gene significantly inhibited apoptosis and autophagy. RNA sequencing and RNA pull down analyses confirmed a competing endogenous RNA pathway in which circ_0001449 sponges miR-124-3p and miR-32-5p to promote Osbpl5 translation. Our data showed that circRNA_0001449 regulates membrane homeostasis via ORP5 and is involved in the AKT survival pathway.

5.
J Cell Physiol ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32020591

RESUMO

Long noncoding RNAs (lncRNAs) have been reported to dysregulate and involve in the pathology of hepatocellular carcinoma (HCC). Nonetheless, the functional role of lncRNA T cell leukemia/lymphoma 6 (TCL6) and its underlying mechanism in HCC remain unclear. Herein, we analyzed the expression of TCL6 and elucidated its mechanistic involvement in HCC. Bioinformatics analyses indicated TCL6 was evidently downregulated in HCC tissues compared with normal controls. TCL6 was downregulated while microRNA-106a-5p (miR-106a-5p) was upregulated in HCC cell lines. Moreover, knockdown or overexpression of TCL6 significantly raised or diminished the expression level of miR-106a-5p in HCC cells, similar to the effect of miR-106a-5p on TCL6 expression. Functionally, TCL6 inhibited the proliferative, migratory, and invasive potentials of HCC cells as analyzed by cell counting kit-8, scratch wound healing, and transwell assays, respectively. Conversely, miR-106a-5p exerted an opposite effect on the proliferative, migratory, and invasive potentials of HCC. RNA immune precipitation and luciferase reporter assays revealed TCL6 directly bound to miR-106a-5p and luciferase reporter assay verified phosphatase and tensin homolog (PTEN) was a target gene of miR-106a-5p. Mechanistically, TCL6 knockdown evidently reduced PTEN expression at both messenger RNA and protein levels, and miR-106a-5p inhibitor partially rescued this reduction effect in HCC cells. Additionally, western blot assays demonstrated miR-106a-5p downregulation or TCL6 overexpression promoted the protein level of PTEN, and suppressed the phosphorylation level of AKT, the protein level of phosphatidylinositol 3-kinase (PI3K). Collectively, these results revealed TCL6 as a tumor-suppressive lncRNA regulates PI3K/AKT signaling pathway via directly binding to miR-106a-5p in HCC. This mechanism provides a theoretical basis for HCC pathogenesis and a potential therapeutic strategy for HCC treatment.

6.
Int Angiol ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32052947

RESUMO

BACKGROUND: Insomnia may affect vascular factors and promote arteriosclerosis. Microparticles (MPs) are a heterogeneous group of bioactive small vesicles that can be found in blood and body fluids following activation, necrosis or apoptosis of virtually any eukaryotic cells. MPs are believed to participate in the pathogenesis of atherosclerosis. Few studies have been concerned with the microparticle level in patients with sleep disorder. The purpose of the present study is to measure the levels of endothelial microparticles (EMPs), platelet microparticles (PMPs) and leukocyte-derived microparticles (LMPs) in middle-aged and elderly patients with or without insomnia. METHODS: Patients with insomnia (n=30) and without insomnia (n=18) were enrolled. The insomnia group covered patients with chronic insomnia (n=16) and acute insomnia (n=14). Levels of EMPs (CD31 +, CD62E +) and PMPs (CD41a +, CD42a +) and granulocyte-derived (CD11a +) MPs were measured. Flow cytometry was performed on the Beckman Coulter analyzer. Reference gate was defined for the level of MPs using 0.22-0.45-0.88µm microspheres, and the size gate for MPs was 0.5-1.0µm. RESULTS: Of all types of MPs detected, the levels of CD31 +MPs, CD62E +MPs and CD11a +MPs were significantly higher in the insomnia group than in the non-insomnia group (P<0.05). Besides, compared with acute insomnia, the levels of CD31 + MPs and CD11a +MPs were significantly higher in chronic insomnia (P<0.001). CONCLUSIONS: In insomnia patients, atherosclerosis progression may be increased by the CD31+ EMPs-mediated apoptosis and endothelial injury. The level of CD11a+ LMPs kept increasing as insomnia persisted, which may indicate atherosclerosis progression.

7.
Mol Brain ; 13(1): 15, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019580

RESUMO

Anxiety disorder is highly prevalent worldwide and represents a chronic and functionally disabling condition, with high levels of psychological stress characterized by cognitive and physiological symptoms. Scopoletin (SP), a main active compound in Angelica dahurica, is traditionally used for the treatment of headache, rhinitis, pain, and other conditions. Here, we evaluated the effects of SP in a mouse model of complete Freund's adjuvant (CFA)-induced chronic inflammation anxiety. SP (2.0, 10.0, 50.0 mg/kg) administration for 2 weeks dose-dependently ameliorated CFA-induced anxiety-like behaviors in the open field test and elevated plus maze test. Moreover, we found that SP treatment inhibited microglia activation and decreased both peripheral and central IL-1ß, IL-6, and TNF-α levels in a dose-dependent manner. Additionally, the imbalance in excitatory/inhibitory receptors and neurotransmitters in the basolateral nucleus after CFA injection was also modulated by SP administration. Our findings indicate that the inhibition of the nuclear factor-kappa B and mitogen-activated protein kinase signaling pathways involving anti-inflammatory activities and regulation of the excitatory/inhibitory balance can be attributed to the anxiolytic effects of SP. Moreover, our molecular docking analyses show that SP also has good affinity for gamma-aminobutyric acid (GABA) transaminase and GABAA receptors. Therefore, these results suggest that SP could be a candidate compound for anxiolytic therapy and for use as a structural base for developing new drugs.

8.
Mil Med Res ; 7(1): 4, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029004

RESUMO

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32043305

RESUMO

AIM: Mullerian duct anomalies (MDA) are common female genital tract malformations. Genetic and environmental factors are important causes of MDA in women. Although many genes and mutations have been found to be associated with the pathogenesis of MDA, in most cases, the genetic pathogenic factors of MDA are still unknown. METHODS: We first analyzed the three sisters using low coverage whole-genome sequencing. Then whole-exome sequencing was carried out in each patient. The identified sequence variant was confirmed by Sanger sequencing. In silico pathogenicity analysis and conservative analysis of the mutation site were also performed. Protein structural modeling was used to analyze the effect of the mutated amino acid. RESULTS: We first analyzed the three sisters with septate uterus using low coverage whole-genome sequencing, but no possible pathogenic copy number variation was found. Then whole-exome sequencing was performed on the three sisters, and a rare homozygous variant, CDC42BPB:c.2012G>A:p.R671Q, was identified. All three patients were found with this variant. Sanger sequencing validated that this variant was segregated within the family. In silico pathogenicity analysis and conservative analysis of the mutation site suggested that the variant might be damaging. Protein structural analysis suggested that R671Q might weaken the electrostatic potential of this region, which may be a significant regulation target or protein interaction surface of CDC42BPB. CONCLUSION: We demonstrated that CDC42BPB genetic variant might be potentially associated with the pathogenesis of MDA.

10.
Health Informatics J ; : 1460458220901889, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32072854

RESUMO

The accurate forecast of radiology emergency patient flow is of great importance to optimize appointment scheduling decisions. This study used a multi-model approach to forecast daily radiology emergency patient flow with consideration of different patient sources. We constructed six linear and nonlinear models by considering the lag effects and corresponding time factors. The autoregressive integrated moving average and least absolute shrinkage and selection operator (Lasso) were selected from the category of linear models, whereas linear-and-radial support vector regression models, random forests and adaptive boosting were chosen from the category of nonlinear models. The models were applied to 4-year daily emergency visits data in the radiology department of West China Hospital in Chengdu, China. The mean absolute percentage error of six models ranged from 8.56 to 9.36 percent for emergency department patients, whereas it varied from 10.90 to 14.39 percent for ward patients. The best-performing model for total radiology visits was Lasso, which yielded a mean absolute percentage error of 7.06 percent. The arrival patterns of emergency department and total radiology emergency patient flows could be modeled by linear processes. By contrast, the nonlinear model performed best for ward patient flow. These findings will benefit hospital managers in managing efficient patient flow, thus improving service quality and increasing patient satisfaction.

11.
Bioorg Chem ; 95: 103457, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901757

RESUMO

OBJECTIVES: The influences of COL1A1 and MZB1 on the proliferation, migration, invasion and apoptosis abilities of rectum adenocarcinoma was aimed to explore in this study. METHODS: Gene expression levels in rectum adenocarcinoma and adjacent tissues were analyzed by differential analysis. Weighted gene correlation network analysis (WGCNA) was employed to investigate rectal adenocarcinoma (READ) hub genes. MCODE was performed to screen the modules of protein-protein interaction network in Cytoscape software. Database for Annotation, Visualization and Integrated Discovery (DAVID) online tool is considered to be the most effective tool in gene ontology (GO) enrichment and Kyoto Gene and Genomics Encyclopedia (KEGG) pathway analysis. Survival analysis was performed using READ patient information from TCGA-READ project database. Quantitative Real-time Polymerase Chain Reaction (qRT-PCR) and western blot were employedto examinemRNA and protein expressions of COL1A1 and MZB1 in tumor tissues and cell lines. After transfecting various interference sequences by liposome-mediated transfection, the influence of COL1A1 and MZB1 on the proliferation, apoptosis, migration and invasion of rectal cancer cells were observed by plate clone formation assay, flow cytometry, wound healing assay and transwell assay respectively. Moreover, xenograft tumor growth assay in vivo validated the results. RESULTS: Higher expression levels of COL1A1 and lower expression levels of MZB1 were discovered in tumor tissues of patients with colorectal adenocarcinoma. Overexpression of MZB1 and silencing COL1A1 significantly inhibited proliferation, migration and invasion, while cell apoptosis was promoted. Overexpression of MZB1 and silencing COL1A1 inhibited the orthotopic growth of tumor in vivo. CONCLUSION: COL1A1 promoted proliferation, migration and invasion but inhibited apoptosis of rectal adenocarcinoma cells while MZB1 was totally on the contrary.

12.
Carbohydr Polym ; 231: 115770, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888821

RESUMO

The development of long-lasting therapeutic drug delivery system is greatly desired for effective treatment of glaucoma, a chronic and multifactorial disease. Herein, the roles of aromatic ring number in phenolic compound-conjugated chitosan injectables are exploited for achieving an advanced drug carrier with potent anti-inflammatory and anti-oxidant properties. Low and high number of aromatic rings can induce deleterious impacts on the pharmaceutical applications of injectables, whereas the compound with a moderate ring number is proved as the most efficient agent for boosting drug delivery performances and endowing the chitosan injectables with therapeutic properties. Kaempferol-conjugated injectable formulation reveals a remarkable effectiveness for intracameral pilocarpine administration, which can alleviate progressive glaucoma via simultaneously exerting multiple pharmacological activities to suppress ocular hypertension, inflammation, and oxidative stress. These findings provide a significant advance in understanding structure-property relationship of the phenolic compound-conjugated chitosan injectables as long-lasting therapeutic drug delivery systems for medical management of glaucoma.

13.
Life Sci ; 245: 117362, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31996295

RESUMO

The prominent feature of obstructive sleep apnea (OSA) is chronic intermittent hypoxia (CIH). Given the strong antioxidant ability of resveratrol against oxidative stress, we evaluated the potential protective effects of resveratrol on myocardial injury induced by CIH. Twenty-four rats were divided into normal control group, CIH group, CIH plus resveratrol treated (CIH + Res) group, and resveratrol treated control (Res) group. We proved that CIH impaired cardiac structure and function with an increase in oxidative stress, endoplasmic reticulum (ER) stress and NOD-like receptors (NLRP3) inflammasome induction in heart, which was attenuated after resveratrol administration. NLRP3 inflammasome blockade by resveratrol appeared to be mediated by activating AMP-activated Protein Kinase (AMPK), which could restrain mTOR/TTP/NLRP3 mRNA signalling. Furthermore, resveratrol attenuated CIH-induced oxidative stress through elevation antioxidant molecules expression via NF-E2-related factor-2 (Nrf2). Moreover, AMPK may play a role in Nrf2/HO-1 signalling by resveratrol. These results expand our understanding of the myocardial protective mechanism of resveratrol during CIH and suggest that resveratrol treatment may be useful to counteract OSA-associated cardiac injury.

14.
J Colloid Interface Sci ; 561: 307-317, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767392

RESUMO

Semiconductor heterojunction powders have exhibited the enhanced photocatalytic activities, but their practical applications have been limited due to their poor recycling performance from flowing wastewater. To solve these problems, with carbon fibers (CFs) as the fixing substrate, we constructed TiO2/CdS heterojunction as a model on CF surface by utilizing a hydrothermal-chemical bath deposition method. CFs/TiO2/CdS bundles display a wide photoabsorption with two photoabsorption edges (~410 and 520 nm). Furthermore, CFs/TiO2/CdS bundles can be weaved into macroscopical cloth (such as weight: 0.1 g, area: 4 × 4 cm2) which have considerable photocurrent density of 5.75 × 10-6 A/cm2. Under visible light irradiation (λ > 400 nm), macroscopic CFs/TiO2/CdS cloth can degrade 95.44% methylene blue (MB), 64.95% acid orange 7 (AO7), 91.37% tetracycline hydrochloride (TC) and remove 90.70% hexavalent chromium (Cr(VI)) after 120 min, higher than those by CFs/CdS (43.42% MB, 37.42% AO7, 31.76% TC and 30.45% Cr(VI)) or CFs/TiO2 (12.84% MB, 10.48% AO7, 11.85% TC and 15.58% Cr(VI)). Thus, CFs/TiO2/CdS can act as a weavable and efficient photocatalyst for eliminating various pollutants from wastewater.

15.
Environ Pollut ; 256: 113428, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706780

RESUMO

As the most important gas-phase alkaline species, atmospheric ammonia (NH3) contributes considerably to the formation and development of fine-mode particles (PM2.5), which affect air quality and environmental health. Recent satellite-based observations suggest that the North China Plain is the largest agricultural NH3 emission source in China. However, our isotopic approach shows that the surface NH3 in the intraregional urban environment of Beijing-Tianjin-Shijiazhuang is contributed primarily by combustion-related processes (i.e., coal combustion, NH3 slip, and vehicle exhaust). Specifically, the Batch fractionation model was used to describe the partitioning of gaseous NH3 into particles and to trace the near-ground atmospheric NH3 sources. With the development of haze pollution, the dynamics of δ15N-NH4+ were generally consistent with the fractionation model. The simulated initial δ15N-NH3 values ranged from -22.6‰ to -2.1‰, suggesting the dominance of combustion-related sources for urban NH3. These emission sources contributed significantly (92% on hazy days and 67% on clean days) to the total ambient NH3 in urban cities, as indicated by a Bayesian mixing model. Based on the Batch fractionation model, we concluded the following: 1) δ15N-NH4+ can be used to model the evolution of fine-mode aerosols and 2) combustion-related sources dominate the near-ground atmospheric NH3 in urban cities. These findings highlight the need for regulatory controls on gaseous NH3 emissions transported from local and surrounding industrial sources.

16.
J Adv Nurs ; 76(1): 163-173, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31566806

RESUMO

AIMS: To examine the mediating effects of self-efficacy, coping, burnout, and social support in the link between job stress and depression and anxiety among young Chinese nurses. DESIGN: A cross-sectional survey was used. METHODS: Full-time young nurses (N = 1,029) who worked in nine tertiary grade A hospitals in Chengdu China were recruited from December 2016-March 2017. Structural equation modelling was applied to analyse the mediating effects. RESULTS: Job stress had a direct positive effect on anxiety (ß = 0.054) and it also exerted indirect positive effects on depression (ß = 0.337) and anxiety (ß = 0.325) through mediating factors. Emotional exhaustion and social support were the main mediating variables, accounting for 72.0% of the variation in anxiety and nearly 43.4% in depression. CONCLUSION: Emotional exhaustion and social support may have significant mediating effects in the link between job stress and depression and anxiety. Strategies including deceasing emotional exhaustion, enhancing social support in work environment, and reducing job stressors would be useful to prevent depression and anxiety among young nurses. IMPACT: What problems did the study address? Depression and anxiety have great impact on professional performance of nurses and even patient safety. Factors such as coping, burnout, etc., may have different mediating effects in the paths from job stress to depression and anxiety. What were the main findings? Job stress had direct and indirect positive effects on anxiety and it only had indirect positive effect on depression. Emotional exhaustion and social support were the main mediating variables in the link between job stress and depression and anxiety. Where and on whom will the research have impact? Nursing managers should be more cognizant of the impact of job stress on the development of depression and anxiety. The significant mediating effect of emotional exhaustion and social support in the link between job stress and depression and anxiety should be emphasized by nursing administrators and effective targeted measures need to be adopted.

17.
Sci Total Environ ; 704: 135329, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31831235

RESUMO

Vertical profiles of PM2.5 (i.e., particulate matter with an aerodynamic diameter of 2.5 µm or less) and meteorological variables (e.g., potential temperature, specific humidity) are crucial to understand formation mechanism including accumulation and dispersion process of PM2.5, as well as interactions between aerosols and the atmospheric boundary layer (ABL). In this study, vertical distributions of PM2.5 are characterized through comprehensive analyses of vertical profiles measured by unmanned aerial vehicle (UAV), Micro Pulse LiDAR, and other surface observational data of a heavy aerosol pollution episode occurring on December 22-25, 2017 in Nanjing, China. Results show that PM2.5 profiles are characterized by a clear three-layer structure with near constant within the mixed layer, a transition layer with a large local gradient in the entrainment zone, and a layer with low concentration and small gradient in the free atmosphere, which shows a large similarity to that of specific humidity. The accumulation of aerosols is found near top of the ABL with the largest increase rate. Vertical distributions of PM2.5 and their evolution are largely constrained by the ABL thermodynamics during daytime, but show much less dependence on the ABL evolution at nighttime. PM2.5 provides an important feedback on the nocturnal boundary layer (NBL) leading to significant modification of vertical distributions of potential temperature and water vapor. Moreover, this study suggests that the current boundary layer parameterization scheme needs refinement with aerosol radiative effect included to further improve the ABL height (ABLH) and air quality predictions.

18.
Int J Health Plann Manage ; 35(1): 79-103, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31149758

RESUMO

This study aims to examine the correlations between air pollution and dynamic stroke mortality, which is defined as the daily real-time number of deaths from stroke. Death data were obtained from daily medical records of 7230 incidents from the Center for Disease Control and Prevention in the Longquanyi District of China from 2016 to 2017. Air pollution data were obtained from environmental monitoring stations in the Longquanyi District. Time series analysis using generalized additive Poisson regression models was applied, and single-pollutant and two-pollutant adjusted models were utilized. Furthermore, categories based on gender, age, and meteorological factors were considered in the analysis. The results indicated that PM2.5, PM10, O3 , and CO had significant effects on dynamic stroke mortality, which were stronger for older people and during the cold season. This study helps hospital managers, patients, and governments seeking to prevent and control the effects of air pollution on the risks of stroke.

19.
Microvasc Res ; 127: 103913, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31449822

RESUMO

The "metabolic memory", a phenomenon that the target cell remembers the early hyperglycemia, has been reported to be a critical issue in diabetes pathogenesis. Here, we confirmed the inducible effects of high glucose (HG) and HG followed by normal glucose (HN) upon the proliferation and the tube formation capacity of human umbilical vein endothelial cells (HUVECs), as well as the suppressive effects of HG and HN on HUVEC apoptosis. In the meantime, the miR-320 expression could be dramatically downregulated (** and ## P < 0.01), whereas VEGFA expression (** and ## P < 0.01) and VEGFA, PKC, and RAGE protein levels could be remarkably induced via HG and HN stimulation. More importantly, the effects of HG and HN were not significantly different, suggesting the existence of high glucose-induced metabolic memory and the involvement of miR-320 and VEGFA in high glucose-induced metabolic memory in HUVECs. Consistently, miR-320 overexpression significantly reversed the effects of HG and HN on HUVECs (* and # P < 0.05, ** and ## P < 0.01). miR-320 suppressed the expression of VEGFA via direct binding to the 3'-UTR of VEGFA mRNA, therefore suppressing high glucose-induced metabolic memory (** P < 0.01); the effects of miR-320 overexpression on HUVECs could be reversed by VEGFA overexpression (# P < 0.05, ## P < 0.01), indicating that miR-320/VEGFA axis modulates the proliferation, apoptosis, and the angiogenesis capacity of HUVECs. In conclusion, we demonstrate that miR-320/VEGFA axis is crucial to high glucose-induced metabolic memory during HUVEC dysfunction and may be involved in the pathology of diabetes.

20.
Crit Care Med ; 48(1): e40-e47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31634234

RESUMO

OBJECTIVES: The knowledge that agmatine is found in the human body has existed for several years; however, its role in sepsis has not yet been studied. In the present study, we investigate the role of agmatine in the progression and treatment of sepsis. DESIGN: Clinical/laboratory investigations. SETTING: Medical centers/University-based research laboratory. SUBJECTS: Elective ICU patients with severe sepsis and healthy volunteers; C57BL/6 mice weighing 18-22 g. INTERVENTIONS: Serum agmatine level and its associations with inflammatory markers were assessed in patients with sepsis. Agmatine was administered intraperitoneally to mice before a lipopolysaccharide challenge. Human peripheral blood mononuclear cells and murine macrophages were pretreated with agmatine followed by lipopolysaccharide stimulation. MEASUREMENTS AND MAIN RESULTS: Serum agmatine levels were significantly decreased in patients with sepsis and lipopolysaccharide-induced mice, and correlated with Acute Physiology and Chronic Health Evaluation II score, procalcitonin, tumor necrosis factor-α, and interleukin-6 levels. In a therapeutic experiment, exogenous agmatine attenuated the cytokine production of peripheral blood mononuclear cells from patients with sepsis and healthy controls. Agmatine also exerted a significant beneficial effect in the inflammatory response and organ damage and reduced the death rate in lipopolysaccharide-induced mice. Imidazoline I2 receptor agonist 2-benzofuran-2-yl blocked the pharmacological action of agmatine; whereas, other imidazoline receptor ligands did not. Furthermore, agmatine significantly impaired the inflammatory response by inactivating nuclear factor-κB, but not protein 38 mitogen-activated protein kinase, c-Jun N-terminal kinase, extracellular signal-regulated kinase, and inducible nitric oxide synthase signaling in macrophages. Activation of imidazoline I2 receptor or knockdown of ribosomal S6 kinase 2 counteracted the effects of agmatine on phosphorylation and degradation of inhibitor of nuclear factor-κBα. CONCLUSIONS: Endogenous agmatine metabolism correlated with the progression of sepsis. Supplemental exogenous agmatine could ameliorate the lipopolysaccharide-induced systemic inflammatory responses and multiple organ injuries through the imidazoline I2 receptor-ribosomal S6 kinase 2-nuclear factor-κB pathway. Agmatine could be used as both a clinical biomarker and a promising pharmaconutrient in patients with severe sepsis.

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