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1.
BMC Public Health ; 24(1): 1733, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943094

RESUMO

BACKGROUND: Childhood obesity is increasingly recognized as a major public health challenge worldwide, and excessive sedentary screen time is emerging as a key risk factor. This study aimed to assess the recreational screen sedentary time of Chinese primary school-aged children and investigate the relationship between screen-related family factors and the outcome variable. METHODS: Our study used data from a cross-sectional survey collected from fifth-grade students and their parents in Beijing, China, from April to May 2018 (n = 2,373). The questions included basic demographic information, family socioeconomic status, students' and parents' sedentary and exercising habits, within-family communicational factors, and health belief patterns. The recreational screen sedentary time of the children was compared across demographic groups. The study employed multivariate linear regression models to examine associations between children's screen time and various family factors, as well as the moderating effect of overall family communication. RESULTS: Our findings revealed an average daily recreational screen sedentary time of 2.4 h among participants. Screen time significantly varied across demographic categories, including children's sex, age, residence, parents' education, household income, family size, and primary family member. After adjustment, the proportion of child-owned digital devices (p < 0.01), child's personal room (p < 0.05), family screen-viewing together (p < 0.01), and parental screen time (p < 0.01) were positively related to children's recreational sedentary screen time. Parental restrictions on screen time (p < 0.001) and attitudes toward reducing sitting time (p < 0.01) were correlated with a decrease in children's screen time. The overall family communication environment significantly moderated the effects of parental practice of restricting children's screen time (p < 0.001), positive reinforcement by parents (p < 0.05), and parents' recreational sedentary screen time (p < 0.001). CONCLUSIONS: Our findings underscored the significance of family dynamics, parental practices, and communication in shaping children's screen time behaviors, providing valuable insights for tailored interventions and strategies to reduce childhood obesity.


Assuntos
Comunicação , Tempo de Tela , Comportamento Sedentário , Humanos , Estudos Transversais , Masculino , Feminino , Criança , China , Pequim , Pais/psicologia , Obesidade Infantil/epidemiologia , Inquéritos e Questionários , Exercício Físico
2.
Medicine (Baltimore) ; 103(17): e37611, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669405

RESUMO

BACKGROUND: Osteoarthritis is a common degenerative joint disease that is highly prevalent in the elderly population. Along with the occurrence of sports injuries, osteoarthritis is gradually showing a younger trend. Osteoarthritis has many causative factors, and its pathogenesis is currently unknown. Cellular senescence is a stable form of cell cycle arrest exhibited by cells in response to external stimuli and plays a role in a variety of diseases. And it is only in the last decade or so that cellular senescence has gradually become cross-linked with osteoarthritis. However, there is no comprehensive bibliometric analysis in this field. The aim of this study is to present the current status and research hotspots of cellular senescence in the field of osteoarthritis, and to predict the future trends of cellular senescence in osteoarthritis research from a bibliometric perspective. METHODS: This study included 298 records of cellular senescence associated with osteoarthritis from 2009 to 2023, with data from the Web of Science Core Collection database. CiteSpace, Scimago Graphica software, VOSviewer, and the R package "bibliometrix" software were used to analyze regions, institutions, journals, authors, and keywords to predict recent trends in cellular senescence related to osteoarthritis research. RESULTS: The number of publications related to cellular senescence associated with osteoarthritis is increasing year by year. China and the United States contribute more than 70% of the publications and are the mainstay of research in this field. Central South University is the most active institution with the largest number of publications. International Journal of Molecular Sciences is the most popular journal in the field with the largest number of publications, while Osteoarthritis and Cartilage is the most cited journal. Loeser, Richard F. is not only the most prolific author, but also the most frequently cited author, contributing greatly to the field. CONCLUSION: In the last decade or so, this is the first bibliometric study that systematically describes the current status and development trend of research on cellular senescence associated with osteoarthritis. The study comprehensively and systematically summarizes and concludes the research hotspots and development trends, providing valuable references for researchers in this field.


Assuntos
Bibliometria , Senescência Celular , Osteoartrite , Osteoartrite/patologia , Senescência Celular/fisiologia , Humanos
3.
Heliyon ; 9(12): e22914, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125535

RESUMO

The prevention, treatment, and rehabilitation of spinal cord injury (SCI) have always posed significant medical challenges. After mechanical injury, disturbances in microcirculation, edema formation, and the generation of free radicals lead to additional damage, impeding effective repair processes and potentially exacerbating further dysfunction. In this context, inflammatory responses, especially the activation of macrophages, play a pivotal role. Different phenotypes of macrophages have distinct effects on inflammation. Activation of classical macrophage cells (M1) promotes inflammation, while activation of alternative macrophage cells (M2) inhibits inflammation. The polarization of macrophages is crucial for disease healing. A non-coding RNA, known as microRNA (miRNA), governs the polarization of macrophages, thereby reducing inflammation following SCI and facilitating functional recovery. This study elucidates the inflammatory response to SCI, focusing on the infiltration of immune cells, specifically macrophages. It examines their phenotype and provides an explanation of their polarization mechanisms. Finally, this paper introduces several well-known miRNAs that contribute to macrophage polarization following SCI, including miR-155, miR-130a, and miR-27 for M1 polarization, as well as miR-22, miR-146a, miR-21, miR-124, miR-223, miR-93, miR-132, and miR-34a for M2 polarization. The emphasis is placed on their potential therapeutic role in SCI by modulating macrophage polarization, as well as the present developments and obstacles of miRNA clinical therapy.

4.
Front Public Health ; 11: 958932, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771832

RESUMO

Background: Since the onset of the COVID-19 pandemic in March 2020, reports of anti-Asian American or Pacific Islander (AAPI) hate have increased in the United States. Institutions of higher education provide a unique opportunity to examine COVID-19 related stigma and protective factors in AAPI young adults enrolled in college. Objective: The goal of this research was to examine COVID-19 related stigma among a diverse college student population. We posited that AAPI students experience more racial discrimination, internalized stigma, and/or anticipated racial discrimination than other students. We also sought to identify protective behavioral factors against stigma. Methods: This study includes data from a repeated cross-sectional survey that was administered among college students at a large public university in the United States in April (n = 1,359) and November 2020 (n = 1,196). All university enrolled students with an active email account were eligible to participate in the online survey, which included questions about COVID-19 stigma (anticipated, enacted, internalized), stigma resistance, sources of COVID-19 information, lifestyle behaviors, and sociodemographic information. Binary logistic regression models were utilized to assess differences in stigma between race and ethnic groups and to identify factors associated with stigma. Results: AAPI students were more likely to experience all three types of stigma compared to other race and ethnic groups. AAPI students in both waves were at least 2 times more likely to experience enacted stigma and 7.3 times more likely to experience anticipated stigma in the earlier wave compared to non-Hispanic White students. Students who had experienced enacted stigma were more likely to experience anticipated stigma, and those who experienced enacted and anticipated stigma were more likely to experience internalized stigma. Higher education level, living with neighbors/roommates, maintaining a healthy lifestyle, and thinking positively about oneself may act as protective factors against different types of stigma. Conclusion: AAPI students have a greater risk of experiencing COVID-19 stigma compared to those from other race and ethnic groups. Universities should combat anti-AAPI sentiments and COVID-19 stigma and promote public health efforts to build resistance against the negative effects of stigma.


Assuntos
COVID-19 , Racismo , Adulto Jovem , Humanos , Estados Unidos/epidemiologia , Estudos Transversais , Universidades , Pandemias , Fatores de Proteção , Estudantes
5.
Mol Plant ; 14(11): 1814-1830, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34242849

RESUMO

Post-translational modifications (PTMs), including phosphorylation and persulfidation, regulate the activity of SNF1-RELATED PROTEIN KINASE2.6 (SnRK2.6). Here, we report how persulfidations and phosphorylations of SnRK2.6 influence each other. The persulfidation of cysteine C131/C137 alters SnRK2.6 structure and brings the serine S175 residue closer to the aspartic acid D140 that acts as ATP-γ-phosphate proton acceptor, thereby improving the transfer efficiency of phosphate groups to S175 to enhance the phosphorylation level of S175. Interestingly, we predicted that S267 and C137 were predicted to lie in close proximity on the protein surface and found that the phosphorylation status of S267 positively regulates the persulfidation level at C137. Analyses of the responses of dephosphorylated and depersulfidated mutants to abscisic acid and the H2S-donor NaHS during stomatal closure, water loss, gas exchange, Ca2+ influx, and drought stress revealed that S175/S267-associated phosphorylation and C131/137-associated persulfidation are essential for SnRK2.6 function in vivo. In light of these findings, we propose a mechanistic model in which certain phosphorylations facilitate persulfidation, thereby changing the structure of SnRK2.6 and increasing its activity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fósforo/metabolismo , Proteínas Quinases/metabolismo , Enxofre/metabolismo , Aclimatação , Arabidopsis/enzimologia , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/metabolismo , Secas , Modelos Moleculares , Mutação , Fosforilação , Ligação Proteica , Conformação Proteica , Proteínas Quinases/genética , Processamento de Proteína Pós-Traducional , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
6.
Plant Physiol Biochem ; 156: 257-266, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32979798

RESUMO

Hydrogen sulfide (H2S), a small gaseous signaling molecule, regulates antioxidase activity and improves plant tolerance to oxidative stress. The phytotoxic effect of Copper Oxide (II) nanoparticles (CuO NPs) is due to oxidative stress. Here, we show that H2S-mediated persulfidation of antioxidase is essential for an effective stress response of tomato exposed to CuO NPs. The CuO NP-induced increase in hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels was significantly reduced by treatment with the H2S donor NaHS. In vivo, NaHS increased superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POD) activities under CuO NP stress. In vitro, NaHS increased APX and POD activities but decreased catalase (CAT) activity. Persulfidation existed in recombinant SlCAT1, SlcAPX1 and SlPOD5 proteins. The persulfidatied cysteine (Cys) residues were verified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), revealing their position on the protein surface. Cys234 of SlCAT1 is located in the immune-responsive domain and close to the enzyme activity domain. Cys234 of SlcAPX1 and Cys 61 SlPOD5 are located in the enzyme activity domain. Persulfidation increased SlcAPX1 and SlPOD5 activities but decreased SlCAT1 activity. These data indicate that H2S-mediated persulfidation posttranslationally regulates the activities of CAT, APX and POD, thereby enhancing the plant's response to oxidative stress. Additionally, this work provides an experimental approach for the study of persulfidation in plants.


Assuntos
Antioxidantes/metabolismo , Cobre/efeitos adversos , Sulfeto de Hidrogênio/farmacologia , Estresse Oxidativo , Solanum lycopersicum/enzimologia , Cromatografia Líquida , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Malondialdeído/metabolismo , Nanopartículas , Plântula/metabolismo , Superóxido Dismutase/metabolismo , Espectrometria de Massas em Tandem
7.
Plant Signal Behav ; 15(11): 1805228, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32772870

RESUMO

Hydrogen sulfide (H2S) is an important gas signal molecule, but little is known about its signal mechanism. Ca2+ is an important second messenger in plant cells, and its fluctuation in the cytoplasm causes downstream physiological responses. Our previous study found that H2S can induce the accumulation of hydrogen peroxide (H2O2). We also found that reactive oxygen species (ROS) can further induce the Ca2+ influx in guard cells by noninvasive micro-teat technology (NMT). This study confirmed that the accumulation of reactive oxygen species to induce Ca2+ signal in guard cells, resulting in stomatal closure. Thus, revealing a novel mechanism of H2S promoting stomatal closure.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sinalização do Cálcio/fisiologia , Peróxido de Hidrogênio/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/metabolismo
8.
J Magn Reson Imaging ; 52(2): 397-406, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32491257

RESUMO

BACKGROUND: Chest computed tomography (CT) has shown tremendous clinical potential for screening, diagnosis, and surveillance of COVID-19. However, safety concerns are warranted due to repeated exposure of X-rays over a short period of time. Recent advances in MRI suggested that ultrashort echo time MRI (UTE-MRI) was valuable for pulmonary applications. PURPOSE: To evaluate the effectiveness of UTE-MRI for assessing COVID-19. STUDY TYPE: Prospective. POPULATION: In all, 23 patients with COVID-19 and with an average interval of 2.81 days between hospital admission and image examination. FIELD STRENGTH/SEQUENCE: 3T; Respiratory-gated three-dimensional radial UTE pulse sequence. ASSESSMENT: Image quality score. Patient- and lesion-based interobserver and intermethod agreement for identifying the representative image findings of COVID-19. STATISTICAL TESTS: Wilcoxon-rank sum test, Kendall's coefficient of concordance (Kendall's W), intraclass coefficients (ICCs), and weighted kappa statistics. RESULTS: There was no significant difference between the image quality of CT and UTE-MRI (CT vs. UTE-MRI: 4.3 ± 0.4 vs. 4.0 ± 0.5, P = 0.09). Moreover, both patient- and lesion-based interobserver agreement of CT and UTE-MRI for evaluating the image signs of COVID-19 were determined as excellent (ICC: 0.939-1.000, P < 0.05; Kendall's W: 0.894-1.000, P < 0.05.). In addition, the intermethod agreement of two image modalities for assessing the representative findings of COVID-19 including affected lobes, total severity score, ground glass opacities (GGO), consolidation, GGO with consolidation, the number of crazy paving pattern, and linear opacities, as well as pseudocavity were all determined as substantial or excellent (kappa: 0.649-1.000, P < 0.05; ICC: 0.913-1.000, P < 0.05). DATA CONCLUSION: Pulmonary MRI with UTE is valuable for assessing the representative image findings of COVID-19 with a high concordance to CT. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY STAGE: 3 J. Magn. Reson. Imaging 2020;52:397-406.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pneumonia Viral/diagnóstico por imagem , Radiografia Torácica , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Betacoronavirus , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Pandemias , Admissão do Paciente , Estudos Prospectivos , Reprodutibilidade dos Testes , SARS-CoV-2 , Adulto Jovem
10.
Lab Chip ; 17(18): 3146-3158, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28809418

RESUMO

Semipermeable cell culture membranes are commonly used in multilayered microfluidic devices to mimic the basement membrane in vivo and to create compartmentalized microenvironments for physiological cell growth and differentiation. However, existing membranes are predominantly made up of synthetic polymers, providing limited capacity to replicate cellular interactions with native extracellular matrices that play a crucial role in the induction of physiological phenotypes. Here we describe a new type of cell culture membranes engineered from native extracellular matrix (ECM) materials that are thin, semipermeable, optically transparent, and amenable to integration into microfluidic cell culture devices. Facile and cost-effective fabrication of these membranes was achieved by controlled sequential steps of vitrification that transformed three-dimensional (3D) ECM hydrogels into structurally stable thin films. By modulating the composition of the ECM, our technique provided a means to tune key membrane properties such as optical transparency, stiffness, and porosity. For microfluidic cell culture, we constructed a multilayered microdevice consisting of two parallel chambers separated by a thin membrane insert derived from different types of ECM. This study showed that our ECM membranes supported attachment and growth of various types of cells (epithelial, endothelial, and mesenchymal cells) under perfusion culture conditions. Our data also revealed the promotive effects of the membranes on adhesion-associated intracellular signaling that mediates cell-ECM interactions. Moreover, we demonstrated the use of these membranes for constructing compartmentalized microfluidic cell culture systems to induce physiological tissue differentiation or to replicate interfaces between different tissue types. Our approach provides a robust platform to produce and engineer biologically active cell culture substrates that serve as promising alternatives to conventional synthetic membrane inserts. This strategy may contribute to the development of physiologically relevant in vitro cell culture models for a wide range of applications.


Assuntos
Técnicas de Cultura de Células/instrumentação , Matriz Extracelular/química , Membranas Artificiais , Técnicas Analíticas Microfluídicas/instrumentação , Animais , Adesão Celular , Técnicas de Cultura de Células/métodos , Células Cultivadas , Módulo de Elasticidade , Desenho de Equipamento , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Permeabilidade
11.
Sci Rep ; 7(1): 3413, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28611413

RESUMO

Red blood cell (RBC) transfusion poses significant risks to critically ill patients by increasing their susceptibility to acute respiratory distress syndrome. While the underlying mechanisms of this life-threatening syndrome remain elusive, studies suggest that RBC-induced microvascular injury in the distal lung plays a central role in the development of lung injury following blood transfusion. Here we present a novel microengineering strategy to model and investigate this key disease process. Specifically, we created a microdevice for culturing primary human lung endothelial cells under physiological flow conditions to recapitulate the morphology and hemodynamic environment of the pulmonary microvascular endothelium in vivo. Perfusion of the microengineered vessel with human RBCs resulted in abnormal cytoskeletal rearrangement and release of intracellular molecules associated with regulated necrotic cell death, replicating the characteristics of acute endothelial injury in transfused lungs in vivo. Our data also revealed the significant effect of hemodynamic shear stress on RBC-induced microvascular injury. Furthermore, we integrated the microfluidic endothelium with a computer-controlled mechanical stretching system to show that breathing-induced physiological deformation of the pulmonary microvasculature may exacerbate vascular injury during RBC transfusion. Our biomimetic microsystem provides an enabling platform to mechanistically study transfusion-associated pulmonary vascular complications in susceptible patient populations.


Assuntos
Endotélio Vascular/citologia , Transfusão de Eritrócitos/efeitos adversos , Lesão Pulmonar/etiologia , Microfluídica/métodos , Estresse Mecânico , Células Cultivadas , Endotélio Vascular/lesões , Hemodinâmica , Humanos , Lesão Pulmonar/patologia , Circulação Pulmonar
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