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1.
Sci Total Environ ; 857(Pt 1): 159340, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36228803

RESUMO

An increasing number of people tend to live in cities, where they suffer from serious air pollution from anthropogenic sources. Vehicle exhaust and cooking emission are closely related to daily life of urban residents, and could be defined as "urban-lifestyle sources". The primary emissions of urban-lifestyle sources tend to form abundant secondary organic aerosols (SOA) through complicated atmospheric chemistry processes. The newly formed SOA is a kind of complex mixture and causes considerable health effects with high uncertainty. Most studies focus on formation pathway, mass growth potential and chemical feature of urban-lifestyle SOA under simple laboratory conditions. Few studies have measured the urban-lifestyle SOA in ambient air, let alone verified laboratory findings under complicated atmospheric conditions. In this work, we established a new method that combined laboratory simulation and field observation, which quantified the urban-lifestyle SOA with high time resolution under the real atmospheric condition. The complex SOA was measured and resolved by a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). The multilinear engine model (ME-2) and multilinear correction methods were used to apply laboratory results into ambient SOA apportionment. It was found that the vehicle source dominated the SOA formation during the diurnal photochemical process, and the SOA:POA ratio of vehicle source was about 1.4 times larger than that of cooking source. The vehicle emission may undergo an alcohol/peroxide & carboxylic acid oxidation pathway and form higher oxidized SOA, while the cooking emission may undergo an alcohol/peroxide oxidation pathway and form relatively lower oxidized SOA. The vehicle SOA and cooking SOA contributed 45.6 % and 24.8 % of OA during a local episode in 2021 winter of downtown Beijing. Our findings could not only provide a new way to quantify urban SOA but also demonstrate some laboratory hypotheses, conducing to understand its ambient contributions, chemical features, and environmental effects.

2.
Emerg Microbes Infect ; : 1-39, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36440484

RESUMO

H6 avian influenza virus (AIV) is one of the most prevalent AIV subtypes in birds globally. To investigate the current situation and characteristics of H6 AIVs circulating in China, we analysed the epidemiology, genetic evolution and pathogenic features of this subtype. During 2000-2021, H6 subtype AIVs spread widely through Southern China and presented high host diversity. On analysing 171 H6 viruses isolated during 2009-2021, dynamic reassortments were observed among H6 and other co-circulating AIV subtypes, and these generated a total of 16 different genotypes. A few H6N6 strains possessed L226 and S228 mutations of hemagglutinin (H3 numbering), which may enhance the affinity of H6 viruses to human receptors. H6N6 viruses also exhibited divergent pathogenicity and growth profiles in vivo and in vitro. Some of the H6N6 viruses could infect mice without mammalian adaptation, and even caused death in this species. Therefore, our study demonstrated that the H6 AIVs posed a potential threat to human health and highlighted the urgent need for continued surveillance and evaluation of the H6 influenza viruses circulating in the field.

3.
Nutrients ; 14(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36145061

RESUMO

BACKGROUND: This study aims to investigate the associations between dietary patterns (breakfast, egg, dairy products, and sugared beverage intake frequencies) and physical fitness among Chinese children and adolescents in Shaanxi Province. METHODS: Data were extracted from the Chinese National Survey on Students' Constitution and Health (CNSSCH). The study ultimately included 7305 participants (48.4% male, 51.6% female) aged 6-22 in Shaanxi Province, China. Multiple linear regression was used to examine the association of the frequency of breakfast, egg, dairy product, and sugared beverage intakes with physical fitness. RESULTS: The frequency of breakfast, egg, and dairy product intakes were all independently and positively associated with the level of physical fitness. The frequency of sugared beverage intake was negatively associated with the level of physical fitness. CONCLUSION: Healthier dietary patterns (i.e., higher breakfast, egg, and dairy product intakes and lower sugared beverage intake) were associated with greater physical fitness. Specifically, maintaining a healthy dietary pattern of breakfast, egg, and dairy product intakes can positively affect the strength and endurance performance of children and adolescents. Increased dairy product intake plays a crucial part in boosting the physical fitness total scores of children and adolescents.


Assuntos
Desjejum , Comportamento Alimentar , Adolescente , Criança , China , Dieta , Feminino , Humanos , Masculino , Aptidão Física
4.
J Clin Med ; 11(14)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35887748

RESUMO

BACKGROUND: Aging and physical inactivity are associated with declines in physical fitness and cognitive function. Active video games have proven to be beneficial for the physical health of older adults, but the exact effect of active video games on physical fitness and cognitive function was still unclear. Based on self-determination theory (SDT), which is a widely used theory of healthy behavior change, this study aimed to explore the effects of an active video game intervention on fitness and cognitive function in older adults. METHODS: A total of 38 participants (mean age = 65.68 ± 3.78 years, 24 female) were randomly assigned to either an intervention group (active video game training) or a control group (no additional intervention). The participants in the intervention group trained for a total of 36 sessions (3 times per week for 50-55 min each) for 12 weeks. The control group continued with their normal daily living. The pre- and posttest measurements included: IPAQ-C score and physical fitness (BMI, body fat percent, blood pressure, reaction time, sit and reach, vital capacity, grip strength, static balance, blood biochemical tests for liver function, kidney function, blood lipids, glucose and insulin levels) and cognitive functions (processing speed, spatial ability, working memory, language ability, associative memory). RESULT: The intervention group showed a significantly smaller decrease in total average physical activity relative to the control group. BMI, vital capacity, systolic blood pressure, diastolic blood pressure, and spatial cognition significantly improved after training in the intervention group (BMI: F = 9.814, p = 0.004, d = -0.93, vital capacity: F = 4.708, p = 0.038, d = 0.67, systolic blood pressure: F = 5.28, p = 0.028, d = -0.68, diastolic blood pressure: F = 6.418, p = 0.016, d = -0.86, spatial cognition: F = 8.261, p = 0.007, d = 0.72). Three measures of static balance (closed eyes) also showed improvements after training (total length of swing: F = 3.728, d = -0.62, total velocity of swing: F = 3.740, d = -0.62, total area of swing: F = 2.920, d = -0.70). No significant training effects were evident in the results from the blood biochemical tests. CONCLUSION: This study indicates a positive influence of active video game training on physical fitness and cognitive function. The use of SDT-based active video game exercise as a feasible, safe, and effective training method for improving community older adults' healthy, promoting group cohesion, and increasing motivation to exercise.

5.
Nutrients ; 14(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35893869

RESUMO

BACKGROUND: This study aimed to explore the characteristics of trends in physical fitness and nutritional status among school-aged students during the COVID-19 pandemic, which could help to develop targeted guidelines and policies for students (adolescents) to promote health during lockdowns resulting from public health emergencies. METHODS: The physical fitness and nutritional status were measured from 2019 to 2021; the correlation between years and grade were analyzed. RESULTS: a declining trend was found in aerobic fitness, strength fitness, speed fitness, and BMI during this lockdown. CONCLUSION: The changes in dietary behavior and the decrease in outdoor physical activities may be the reason for the decline. Furthermore, differences in subjects' growth and limited space at home must be considered in the formulation of exercise and nutritional plans. According to the results of our study, exercise for aerobic fitness should receive more attention when students are enduring a pandemic lockdown. In addition, saying "no" to high-calorie foods in the form of snacking and ultra-processed food was the key to improving subjects' nutritional status.


Assuntos
COVID-19 , Estado Nutricional , Adolescente , COVID-19/epidemiologia , Criança , China/epidemiologia , Controle de Doenças Transmissíveis , Estudos Transversais , Promoção da Saúde , Humanos , Pandemias , Aptidão Física
6.
Artigo em Inglês | MEDLINE | ID: mdl-35805608

RESUMO

BACKGROUND: This research aimed to investigate the correlation between students' physical fitness and campus-built environment, which could put forward some suggestions for the construction of a campus environment. METHOD: Four colleges in Xi'an were regarded as special "semi-closed" spaces. Combined with ArcGIS and SPSS, the correlation between the built environment of colleges and the students' physical fitness test results in 2019 was analyzed (n = 1498). RESULTS: regarding the men questioned in this research, there was a significant correlation between street connectivity and vital capacity, grip strength, 50 m running, 1000 m running, a significant correlation between land use mix and vital capacity, sit-and-reach, pull-up, grip strength, a significant correlation between green space per capita and vital capacity, grip strength, 50 m running, and a significant correlation between walk score and vital capacity, pull-up, grip strength, and 50 m running. Regarding the women questioned in this research, there was a significant correlation between street connectivity and vital capacity, grip strength, 50 m running, 800 m running, curl-up, a significant correlation between land use mix and vital capacity, sit-and-reach, curl-up, grip strength, 800 m running, a significant correlation between green space per capita and vital capacity, grip strength, curl-up, sit-and-reach, and a significant correlation between walk score and vital capacity, curl-up, grip strength, and 800 m running. CONCLUSION: the built environment on campus can indirectly affect the physical fitness of college students. Increasing the number of intersections and short connections of campus streets, ensuring that the green space of the campus meets the standards, and reasonably arranging the site selection of buildings are conducive to improving the physical fitness of students.


Assuntos
Sistemas de Informação Geográfica , Aptidão Física , Ambiente Construído , Feminino , Humanos , Masculino , Estudantes , Universidades
7.
Sci Total Environ ; 842: 156573, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35738368

RESUMO

The refractive index of ambient aerosols is widely used in the climate model and remote sensing. Traditionally, the real part of the refractive index (RRI) of the ambient aerosol is calculated from the measured mass fraction of the main inorganic components with known refractive index, without full resolving the effects of variation in the RRI of organic components, which always contribute more than 50 % of the total aerosol mass. For the first time, the ambient aerosol RRI and the aerosol chemical components were measured concurrently at a suburban site Changping, in Beijing, China. Measurements results show that the ambient aerosol ranges between 1.57 and 1.71 with a mean value of 1.66. The mean mass fractions of organic aerosol (OA), nitrate, sulfate, ammonium, and chloride to total non-refractory aerosol loading are 43.1 %, 21.9 %, 21.6 %, 13.1 %, and 0.3 % respectively. Source appointment analysis of the organic aerosol show that the fossil fuel-related OA, cooking OA, biomass burning OA, less oxidized oxygenated OA and more oxidized OOA contributes 18.0 %, 11.2 %, 4.1 %, 39.9 %, 26.7 % to the total aerosol. A new parameterization scheme of the ambient aerosol RRI, which considers the source appointed OA, is proposed based on the concurrent measurements of RRI and chemical composition. The measured and parameterized RRI shows good consistency with a correlation coefficient of 0.79 and slope of 0.98. Our measurement results reveal that a significant deviation of the calculated RRI exists without considering the variation of the RRI of the aerosol organic component. The parametrization scheme is adopted and applicable in aerosol model for bettering estimating the corresponding optical and radiative effects.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Compostos Orgânicos/análise , Material Particulado/análise , Refratometria
8.
J Environ Sci (China) ; 114: 249-258, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459490

RESUMO

Herein, we use an oxidation flow reactor, Gothenburg: Potential Aerosol Mass (Go: PAM) reactor, to investigate the secondary organic aerosol (SOA) formation from wheat straw burning. Biomass burning emissions are exposed to high concentrations of hydroxyl radicals (OH) to simulate processes equivalent to atmospheric oxidation of 0-2.55 days. Primary volatile organic compounds (VOCs) were investigated, and particles were measured before and after the Go: PAM reactor. The influence of water content (i.e. 5% and 11%) in wheat straw was also explored. Two burning stages, the flaming stage, and non-flaming stages, were identified. Primary particle emission factors (EFs) at a water content of 11% (∼3.89 g/kg-fuel) are significantly higher than those at a water content of 5% (∼2.26 g/kg-fuel) during the flaming stage. However, the water content showed no significant influence at the non-flaming stage. EFs of aromatics at a non-flaming stage (321.8±46.2 mg/kg-fuel) are larger than that at a flaming stage (130.9±37.1 mg/kg-fuel). The OA enhancement ratios increased with the increase in OH exposure at first and decreased with the additional increment of OH exposure. The maximum OA enhancement ratio is ∼12 during the non-flaming stages, which is much higher than ∼ 1.7 during the flaming stages. The mass spectrum of the primary wheat burning organic aerosols closely resembles that of resolved biomass burning organic aerosols (BBOA) based on measurements in ambient air. Our results show that large gap (∼60%-90%) still remains to estimate biomass burning SOA if only the oxidation of VOCs were included.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Biomassa , Compostos Orgânicos Voláteis/análise , Água
9.
Emerg Infect Dis ; 28(7): 1332-1344, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35476714

RESUMO

The recent rise in the frequency of influenza A(H5N6) infections in China has raised serious concerns about whether the risk for human infection has increased. We surveyed epidemiologic, clinical, and genetic data of human infections with A(H5N6) viruses. Severe disease occurred in 93.8% of cases, and the fatality rate was 55.4%. Median patient age was 51 years. Most H5N6 hemagglutinin (HA) genes in human isolates in 2021 originated from subclade 2.3.4.4b; we estimated the time to most recent common ancestor as June 16, 2020. A total of 13 genotypes with HA genes from multiple subclades in clade 2.3.4.4 were identified in human isolates. Of note, 4 new genotypes detected in 2021 were the major causes of increased H5N6 virus infections. Mammalian-adapted mutations were found in HA and internal genes. Although we found no evidence of human-to-human transmission, continuous evolution of H5N6 viruses may increase the risk for human infections.


Assuntos
Vírus da Influenza A , Influenza Aviária , Influenza Humana , Animais , China/epidemiologia , Humanos , Mamíferos , Pessoa de Meia-Idade , Filogenia , Vírus Reordenados/genética
10.
J Diabetes Complications ; 36(5): 108170, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35305868

RESUMO

BACKGROUND: Potassium inwardly rectifying channel, subfamily J member 11(KCNJ11) is considered to be a potential susceptible gene of type 2 diabetes mellitus (T2DM), and the association between KCNJ11 E23K polymorphism and T2DM risk is still controversial worldwide. This meta-analysis was performed to assess the association more accurately between KCNJ11 E23K polymorphism and T2DM risk. METHODS: The up-to-data meta-analysis was conducted based on studies selected from eight databases (PubMed, Web of Science, Medline, Scopus, Embase, CNKI, WanFang, and Vip). Five gene models were included in our study: allele model (K-allele vs. E-allele), heterozygous model (EK vs. EE), homozygous model (KK vs. EE), dominant genetic model (EK + KK vs. EE), and recessive genetic model (EK + EE vs. KK). Association strength was evaluated by odds ratio (OR) and 95% confidence interval (CI), publication bias was evaluated by Begg's funnel plot and Egger's test, sensitivity analysis and trial sequential analysis (TSA) were used to evaluate the stability of the results. RESULTS: According to the inclusion and exclusion criteria, 31 eligible articles were finally selected in our meta-analysis, including 8754 T2DM cases and 7587 controls. We found that allelic model (OR = 1.25, 95%CI: 1.15-1.35, P < 0.01), heterozygous model (OR = 1.31, 95% CI: 1.18-1.44, P < 0.01), homozygous model (OR = 1.48, 95% CI: 1.24-1.76, P < 0.01), and dominant genetic model (OR = 1.35, 95% CI: 1.22-1.50, P < 0.01) were significantly associated with increased risk of T2DM, but recessive genetic model (OR = 0.78, 95% CI: 0.67-0.91, P < 0.01) was considered as a protective factor for T2DM. No significant evidence of publication bias was found. CONCLUSION: Our meta-analysis confirms the association between KCNJ11 E23K polymorphism and the risk of T2DM, highlighting that gene-gene interaction and gene-environment interaction should be investigated in future.


Assuntos
Diabetes Mellitus Tipo 2 , Polimorfismo Genético , Canais de Potássio Corretores do Fluxo de Internalização , Alelos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Canais de Potássio Corretores do Fluxo de Internalização/genética
11.
BMC Cardiovasc Disord ; 22(1): 126, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331149

RESUMO

BACKGROUND: Myocardial infarction (MI) remains the leading cause of death and disability among cardiovascular diseases worldwide. Studies show that elevated low-density lipid protein cholesterol (LDL-C) levels confer the highest absolute risk of MI, and Apolipoprotein E (ApoE) is implicated in regulating levels of triglycerides (TGs), cholesterol, and LDL-C. Our study aimed to evaluate the association between APOE polymorphism and MI, and to provide evidence for the etiology of MI. METHODS: Case-control studies on the association between APOE polymorphisms and the risk of myocardial infarction were included by searching PubMed, Web of Science, and CNKI, and this meta-analysis was written in accordance with PRISMA guideline statement. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using either random-effects or fixed-effects models by R software. RESULTS: A total of 33 eligible articles involving 13,706 cases and 14,817 controls were finally selected. The pooled analysis based on the total eligible articles showed that the risk of MI was associated with ApoE epsilon 2 and epsilon 4 alleles. The results showed that patients with MI had a low frequency of the ε2 allele (OR 0.74, 95% CI 0.64-0.86) and a high frequency of the ε4 allele (OR 1.24, 95% CI 1.09-1.42). CONCLUSIONS: APOE ε2-involved genotypes may be protective factors for MI; in contrast, ε4-involved genotypes (ε4/ε3 vs. ε3/ε3, and ε4/ε4 vs. ε3/ε3) may be risk factors for MI.


Assuntos
Apolipoproteínas E/genética , Infarto do Miocárdio , Alelos , Apolipoproteína E2/genética , LDL-Colesterol , Predisposição Genética para Doença , Genótipo , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/genética , Polimorfismo Genético
12.
BMC Public Health ; 22(1): 342, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35177044

RESUMO

BACKGROUND: Multimorbidity is defined as two or more chronic health conditions existing in an individual simultaneously. Multimorbidity has been associated with poor conditions, such as higher health care costs and the poor quality of life. Thus, identifying the risk factors of the multimorbidity is required for multimorbidity prevention. METHODS: This study was based on the Comprehensive Demonstration Research Project of Major Chronic Noncommunicable Disease Prevention and Control Technology in Northeast China initiated by China Medical University. The investigation was a cross-sectional study under a multistage stratified cluster random sampling design. Associations between multimorbidity and sociodemographic and behavioral factors in adult residents were investigated using univariate analysis and multivariate logistic regression analysis. RESULTS: A total of 6706 participants were enrolled in this investigation, and the prevalence of multimorbidity was 21.2% among the adult residents of northeastern China. There existed differences of association between age and multimorbidity risks (65-69 years old: OR = 3.53, 95%CI: 2.04-6.12; 70-74 years old: OR = 5.26, 95%CI: 3.02-9.17). Participants who are overweight had significantly high multimorbidity risk (OR = 2.76, 95%CI: 1.50-5.24). Family history of hypertension and family history of diabetes were significantly associated with high multimorbidity risk (family history of hypertension: OR = 2.34, 95%CI: 1.96-2.79; family history of diabetes: OR = 1.77, 95%CI: 1.38-2.26). Compared with the frequency of fatigue (< 1 time/week or 1-2 times/week), that (≥3 times/week) was associated with high multimorbidity risk (OR = 1.39, 95%CI: 1.07-1.81). For fresh fruit consumption, compared with eating fruits regularly, eating rarely had a higher risk of multimorbidity (OR = 2.33, 95%CI: 1.90-2.85). CONCLUSIONS: Sociodemographic indices (age, BMI, family history of hypertension, and family history of diabetes) and behavioral indices (fatigue status and fresh fruit consumption) increase the risks of multimorbidity. This study provides a necessary route to prevent and control multimorbidity in northeast China.


Assuntos
Diabetes Mellitus , Hipertensão , Adulto , Idoso , China/epidemiologia , Doença Crônica , Estudos Transversais , Diabetes Mellitus/epidemiologia , Fadiga , Humanos , Hipertensão/epidemiologia , Multimorbidade , Prevalência , Qualidade de Vida
13.
J Chromatogr A ; 1665: 462808, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35032735

RESUMO

Ambient gas- and particle-phase intermediate volatility and semi-volatile organic compounds (I/SVOCs) of Beijing were analyzed by a thermal desorption comprehensive two-dimensional gas chromatography quadrupole mass spectrometry (TD-GC × GC-qMS). A pixel-based scheme combing the integration-based approach was applied for partition coefficients estimation and fingerprints identification. Blob-by-blob recognition was firstly utilized to characterize I/SVOCs from the molecular level. 412 blobs in gas-phase and 460 blobs in particle-phase were resolved, covering a total response of 47.5% and 43.5%. A large pool of I/SVOCs was found with a large diversity of chemical classes in both gas- and particle-phase. Acids (8.5%), b-alkanes (5.8%), n-alkanes (C8-C25, 5.3%), and aromatics (4.4%) were dominant in gas-phase while esters (7.0%, including volatile chemical product compounds, VCPs), n-alkanes (C9-C34, 5.7%), acids (4.6%), and siloxanes (3.6%) were abundant in particle-phase. Air pollutants were then evaluated by a two-parameter linear free energy relationship (LFER) model, which could be further implemented in the two-dimensional volatility basis set (2D-VBS) model. Multiway principal component analysis (MPCA) and partial least squares-discriminant analysis (PLS-DA) implied that naphthalenes, phenol, propyl-benzene isomers, and oxygenated volatile organic compounds (OVOCs) were key components in the gas-phase under different pollution levels. This work gives more insight into property estimation and fingerprints identification for complex ambient samples.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Alcanos , Ésteres , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos Voláteis/análise
15.
Int J Mol Sci ; 22(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34830222

RESUMO

Exercise training has been reported to alleviate cardiac fibrosis and ameliorate heart dysfunction after myocardial infarction (MI), but the molecular mechanism is still not fully clarified. Fibroblast growth factor 21 (FGF21) exerts a protective effect on the infarcted heart. This study investigates whether exercise training could increase FGF21 protein expression and regulate the transforming growth factor-ß1 (TGF-ß1)-Smad2/3-MMP2/9 signaling pathway to alleviate cardiac fibrosis following MI. Male wild type (WT) C57BL/6J mice and Fgf21 knockout (Fgf21 KO) mice were used to establish the MI model and subjected to five weeks of different types of exercise training. Both aerobic exercise training (AET) and resistance exercise training (RET) significantly alleviated cardiac dysfunction and fibrosis, up-regulated FGF21 protein expression, inhibited the activation of TGF-ß1-Smad2/3-MMP2/9 signaling pathway and collagen production, and meanwhile, enhanced antioxidant capacity and reduced cell apoptosis in the infarcted heart. In contrast, knockout of Fgf21 weakened the cardioprotective effects of AET after MI. In vitro, cardiac fibroblasts (CFs) were isolated from neonatal mice hearts and treated with H2O2 (100 µM, 6 h). Recombinant human FGF21 (rhFGF21, 100 ng/mL, 15 h) and/or 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR, 1 mM, 15 h) inhibited H2O2-induced activation of the TGF-ß1-Smad2/3-MMP2/9 signaling pathway, promoted CFs apoptosis and reduced collagen production. In conclusion, exercise training increases FGF21 protein expression, inactivates the TGF-ß1-Smad2/3-MMP2/9 signaling pathway, alleviates cardiac fibrosis, oxidative stress, and cell apoptosis, and finally improves cardiac function in mice with MI. FGF21 plays an important role in the anti-fibrosis effect of exercise training.


Assuntos
Terapia por Exercício/métodos , Fatores de Crescimento de Fibroblastos/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miocárdio/patologia , Transdução de Sinais/genética , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Apoptose/genética , Células Cultivadas , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/genética , Fibroblastos/metabolismo , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-34682535

RESUMO

PURPOSE: Regular physical activity (PA) strengthens muscles and improves balance and coordination of human body. The aim of this study was to examine whether objectively measured physical activity (PA) and sedentary behaviors were related to static balance in young men and women. DESIGN AND SETTING: Cross-sectional community study. PARTICIPANTS: 86 healthy adults (50% women) aged 21.26 ± 2.11 years. METHOD: PA variables, including moderate-to-vigorous PA (MVPA), light PA (LPA), sedentary time (SED), and sedentary breaks, were measured by accelerometers on wrist (ActiGraph WGT3X-BT). The static balance was tested in the bipedal stance with eyes open or closed. The movement of the center of pressure, including total sway path length (SP), sway velocity (SV), and sway area (SA), was recorded with a three-dimensional force platform (Kistler 9287CA). The associations between PA (MVPA/LPA/SED/sedentary breaks) and static balance (SP/SV/SA) were analyzed using mixed linear regression analyses, with adjustments for condition (eyes open/closed), sex, age, body mass index (BMI), total device wearing time, and PA*condition. Data were analyzed with SPSS 24.0. RESULTS: Better performance was observed in eyes-open condition (p < 0.05). MVPA was negatively associated with SA (p = 0.030), and SED was positively associated with SA after adjustments, respectively (p = 0.0004). No significance was found in the association of light PA, SED, or sedentary breaks with other static balance variables, respectively (p > 0.05). CONCLUSION: Increasing MVPA and less SED are associated with lower sway area measured by force platform, indicating more PA may related to better static balance in young adults.


Assuntos
Acelerometria , Exercício Físico , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Comportamento Sedentário , Adulto Jovem
17.
Environ Pollut ; 290: 118032, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467886

RESUMO

The annual mean PM2.5 mass concentration has decreased because of the stringent emission controls implemented in Beijing, China in recent years, whereas the nitrate NO3- mass fraction in PM2.5 increases gradually. Low-visibility events occur frequently even though PM2.5 pollution has been mitigated significantly, with the daily mean PM2.5 mass concentration mostly less than 75 µg/m3. In this study, the non-linear relationship was analyzed between atmospheric visibility and PM2.5 based on chemical composition from a two-year field observation. Our results showed that NO3- became the main constituent of PM2.5, especially during the haze pollution episodes. A localized parameterization scheme was proposed between the atmospheric extinction coefficient (σext) and major chemical constituents of PM2.5 by multiple linear regression (MLR). The contribution of NO3- to σext increased with increasing air pollution, and NO3- became the most important contributor for PM2.5 above 75 µg/m3. The visibility decreased with increasing NO3- mass fraction for the same PM2.5 mass concentration when PM2.5 was above 20 µg/m3. The hygroscopicity of PM2.5 increased with increasing mass fraction of hygroscopic NO3-. These results stressed the importance of reducing particulate NO3- and its precursors (for instance, NH3) through effective emission control measures as well as the tightening of PM2.5 standards to further improve air quality and visibility in Beijing.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Monitoramento Ambiental , Nitratos , Material Particulado/análise , Estações do Ano
18.
Science ; 373(6557): 918-922, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34413236

RESUMO

Zoonotic avian influenza A virus (IAV) infections are rare. Sustained transmission of these IAVs between humans has not been observed, suggesting a role for host genes. We used whole-genome sequencing to compare avian IAV H7N9 patients with healthy controls and observed a strong association between H7N9 infection and rare, heterozygous single-nucleotide variants in the MX1 gene. MX1 codes for myxovirus resistance protein A (MxA), an interferon-induced antiviral guanosine triphosphatase known to control IAV infections in transgenic mice. Most of the MxA variants identified lost the ability to inhibit avian IAVs, including H7N9, in transfected human cell lines. Nearly all of the inactive MxA variants exerted a dominant-negative effect on the antiviral function of wild-type MxA, suggesting an MxA null phenotype in heterozygous carriers. Our study provides genetic evidence for a crucial role of the MX1-based antiviral defense in controlling zoonotic IAV infections in humans.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana/genética , Influenza Humana/virologia , Proteínas de Resistência a Myxovirus/genética , Doenças dos Trabalhadores Agrícolas/genética , Doenças dos Trabalhadores Agrícolas/virologia , Animais , Linhagem Celular , Predisposição Genética para Doença , Variação Genética , Heterozigoto , Humanos , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Vírus da Influenza A/fisiologia , Mutação de Sentido Incorreto , Proteínas de Resistência a Myxovirus/química , Proteínas de Resistência a Myxovirus/metabolismo , Aves Domésticas , Zoonoses Virais , Sequenciamento Completo do Genoma
19.
Sci Total Environ ; 795: 148809, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34328915

RESUMO

Chassis dynamometer experiments were conducted to investigate the effect of vehicle speed and usage of ethanol-blended gasoline (E10) on formation and evolution of gasoline vehicular secondary organic aerosol (SOA) using a Gothenburg Potential Aerosol Mass (Go: PAM) reactor. The SOA forms rapidly, and its concentration exceeds that of primary organic aerosol (POA) at an equivalent photochemical age (EPA) of ~1 day. The particle effective densities grow from 0.62 ± 0.02 g cm-3 to 1.43 ± 0.07 g cm-3 with increased hydroxyl radical (OH) exposure. The maximum SOA production under idling conditions (4259-7394 mg kg-fuel-1) is ~20 times greater than under cruising conditions. There was no statistical difference between SOA formation from pure gasoline and its formation from E10. The slopes in Van Krevelen diagram indicate that the formation pathways of bulk SOA includes the addition of both alcohol/peroxide functional groups and carboxylic acid formation from fragmentation. A closure estimation of SOA based on bottom-up and top-down methods shows that only 16%-38% of the measured SOA can be explained by the oxidation of measured volatile organic compounds (VOCs), suggesting the existence of missing precursors, e.g. unmeasured VOCs and probably semivolatile or intermediate volatile organic compounds (S/IVOCs). Our results suggest that applying parameters obtained from unified driving cycles to model SOA concentrations may lead to large discrepancies between modeled and ambient vehicular SOA. No reduction in vehicular `SOA production is realized by replacing normal gasoline with E10.


Assuntos
Poluentes Atmosféricos , Gasolina , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Gasolina/análise , Emissões de Veículos/análise
20.
Sci Total Environ ; 786: 147418, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33975110

RESUMO

Links between the optical properties and chemical compositions of brown carbon (BrC) are poorly understood because of the complexity of BrC chromophores. We conducted field studies simultaneously at both vehicle-influenced site and biomass burning-affected site in China in polluted winter. The chemical compositions and light absorption values of functionalized aromatic compounds, including phenyl aldehyde, phenyl acid, and nitroaromatic compounds, were measured. P-phthalic acid, nitrophenols and nitrocatechols were dominant BrC species, accounting for over 50% of the concentration of identified chromophores. Nitrophenols and nitrocatechols contributed more than 50% of the identified BrC absorbance between 300 and 400 nm. Oxidation of biomass burning-related products (e.g., pyrocatechol and methylcatechols) and anthropogenic volatile organic compounds (e.g., benzene and toluene) generated similar BrC chromophores, implying that these functionalized aromatic compounds play an important role in both environments. Compared with the biomass burning-affected site (22%), functionalized aromatic compounds at vehicle-influenced site accounted for a higher percentage of BrC absorption (25%). This research improves our understanding of the links between optical properties and composition of BrC, and the difference between BrC chromophores from BB-influenced area and vehicle-affected area under polluted atmospheric conditions.

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