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1.
J Med Internet Res ; 24(10): e36134, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36315229

RESUMO

BACKGROUND: This is a systematic review of randomized controlled trials and a meta-analysis comparing smart technology with face-to-face physical activity (PA) interventions in community-dwelling older adults (mean age 60 years). OBJECTIVE: This study aims to determine the effect of interventions including smart technology components compared with face-to-face PA interventions on PA and physical function in older adults. The secondary outcomes are depression, anxiety, and health-related quality of life. METHODS: We searched MEDLINE, Embase, CINAHL, and AMED electronic databases from inception to February 2021. Two independent reviewers screened titles, abstracts, and full texts and performed data extraction and risk of bias assessments using the Cochrane risk of bias tool. The Grading of Recommendations Assessment, Development and Evaluation was used to evaluate the quality of the evidence. We provided a narrative synthesis on all included studies and, where possible, performed meta-analyses for similar outcomes. RESULTS: This review included 19 studies with a total of 3455 participants. Random effects meta-analyses showed that interventions with smart technology components resulted in improved step count (mean difference 1440 steps, 95% CI 500-2390) and total PA (standardized mean difference 0.17, 95% CI 0.02-0.32) compared with face-to-face alone. There was no difference between groups in terms of the measures of physical function. Smart technology alone did not show significant differences between groups in any outcome. The quality of the evidence was very low based on the Grading of Recommendations Assessment, Development and Evaluation criteria. CONCLUSIONS: Interventions that include smart technology may improve daily step counts by an average of 1440 steps in community-dwelling older adults; however, the quality of the evidence was very low. Future studies are needed to improve the certainty of these results. TRIAL REGISTRATION: PROSPERO CRD42020135232; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=135232.


Assuntos
Exercício Físico , Qualidade de Vida , Humanos , Idoso , Pessoa de Meia-Idade , Vida Independente , Ansiedade , Tecnologia
2.
JBI Evid Synth ; 19(10): 2801-2812, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34494613

RESUMO

OBJECTIVE: The objective of this review is to determine the effect of physical activity interventions delivered via smart technology compared with face-to-face interventions for improving physical activity and physical function in older adults. INTRODUCTION: Physical activity is a modifiable risk factor for multiple noncommunicable diseases and reduces the risk of premature mortality. Despite this, one in four adults does not meet recommended levels of physical activity. This pattern of inactivity increases with age. Smart technology, such as wearables, tablets, or laptops, is one solution for improving physical activity. Research has shown that different smart technology solutions can increase physical activity in older adults. While individual studies support smart technology to increase physical activity, there are no systematic reviews comparing the effects of smart technology with traditional face-to-face physical activity interventions. INCLUSION CRITERIA: We will include randomized controlled trials of physical activity interventions delivered via smart technology (eg, wearables, tablets, computers) compared with face-to-face (ie, in person) interventions for community-dwelling older adults aged 60 years or older. METHODS: We will search four databases (AMED, CINAHL, Embase, MEDLINE) from inception for relevant studies. All abstracts and full texts will be screened independently and in duplicate. Risk of bias, data extraction, and quality assessment will be completed in the same manner. If possible, a meta-analysis will be performed of the primary outcomes of physical activity, physical function, and adherence rate. Subgroup analyses will be conducted by type of physical activity, and type of smart technology, where possible. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42020135232.


Assuntos
Exercício Físico , Vida Independente , Idoso , Humanos , Metanálise como Assunto , Microcomputadores , Comportamento Sedentário , Revisões Sistemáticas como Assunto , Tecnologia
3.
Int J Biochem Cell Biol ; 43(8): 1079-85, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21513814

RESUMO

Cysteine residues in proteins are covalently modified under conditions of oxidative and nitrosative stress by oxidation, nitrosation, glutathionylation and disulfide formation. Modifications induce conformational changes in substrate proteins, effecting signal cascades that evoke a biological response. A growing number of structures with modified cysteines are allowing a piecemeal understanding of the mechanistic aspects of these signalling pathways to emerge. Conformational changes upon conjugation of nitric oxide and glutathione are generally small and often accompanied by a local increase in protein disorder. Burial of nitric oxide is also apparent, which may increase the timeframe of signalling. Conformational changes upon disulfide formation/reduction range from the small to the spectacular. They include order/disorder transitions; oxidation of disulfides following expulsion of metals such as Zn; major reorganisation or "morphing" of portions of the polypeptide backbone; and changes in quaternary structure including domain swapping.


Assuntos
Cisteína/metabolismo , Dissulfetos/metabolismo , Glutationa/metabolismo , Proteínas/metabolismo , Cisteína/química , Dissulfetos/química , Glutationa/química , Humanos , Modelos Moleculares , Oxirredução , Conformação Proteica , Estrutura Terciária de Proteína , Proteínas/química , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
4.
Antioxid Redox Signal ; 12(1): 53-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19634988

RESUMO

The molecular mechanisms underlying thiol-based redox control are poorly defined. Disulfide bonds between Cys residues are commonly thought to confer extra rigidity and stability to their resident protein, forming a type of proteinaceous spot weld. Redox biologists have been redefining the role of disulfides over the last 30-40 years. Disulfides are now known to form in the cytosol under conditions of oxidative stress. Isomerization of extracellular disulfides is also emerging as an important regulator of protein function. The current paradigm is that the disulfide proteome consists of two subproteomes: a structural group and a redox-sensitive group. The redox-sensitive group is less stable and often associated with regions of stress in protein structures. Some characterized redox-active disulfides are the helical CXXC motif, often associated with thioredoxin-fold proteins; and forbidden disulfides, a group of metastable disulfides that disobey elucidated rules of protein stereochemistry. Here we discuss the role of redox-active disulfides as switches in proteins.


Assuntos
Dissulfetos/metabolismo , Cisteína/metabolismo , Oxirredução , Proteínas/metabolismo
5.
Protein Sci ; 18(8): 1745-65, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19598234

RESUMO

Disulfides are conventionally viewed as structurally stabilizing elements in proteins but emerging evidence suggests two disulfide subproteomes exist. One group mediates the well known role of structural stabilization. A second redox-active group are best known for their catalytic functions but are increasingly being recognized for their roles in regulation of protein function. Redox-active disulfides are, by their very nature, more susceptible to reduction than structural disulfides; and conversely, the Cys pairs that form them are more susceptible to oxidation. In this study, we searched for potentially redox-active Cys Pairs by scanning the Protein Data Bank for structures of proteins in alternate redox states. The PDB contains over 1134 unique redox pairs of proteins, many of which exhibit conformational differences between alternate redox states. Several classes of structural changes were observed, proteins that exhibit: disulfide oxidation following expulsion of metals such as zinc; major reorganisation of the polypeptide backbone in association with disulfide redox-activity; order/disorder transitions; and changes in quaternary structure. Based on evidence gathered supporting disulfide redox activity, we propose disulfides present in alternate redox states are likely to have physiologically relevant redox activity.


Assuntos
Dissulfetos/metabolismo , Metais/metabolismo , Proteínas/química , Biologia Computacional , Bases de Dados de Proteínas , Dissulfetos/química , Oxirredução , Conformação Proteica , Estrutura Terciária de Proteína/fisiologia , Proteínas/metabolismo
6.
Microbes Infect ; 11(5): 599-611, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19379825

RESUMO

The paradigm of effector T helper cell differentiation into either Th1 or Th2 lineages has been notably shaken by the discovery of a third lineage of cells that selectively produce interleukin (IL)-17. Characterization of this new subset, referred to as Th17, has provided exciting new insights into immunoregulation, host defense and the pathogenesis of autoimmune diseases. Additionally, the discovery of this T cell subset has offered a fresh look at such concepts as lineage commitment and terminal differentiation. The transcriptional regulatory events and epigenetic modifications that control these processes are diverse and complex, and despite the rapid pace at which data continue to accumulate, many questions remain to be answered. Here we review our current understanding of the signaling pathways, molecular interactions and transcriptional events that lead to Th17 differentiation and effector function, as well as the epigenetic modifications that accompany them.


Assuntos
Subpopulações de Linfócitos/imunologia , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/imunologia , Diferenciação Celular , Humanos , Interleucina-17/imunologia , Subpopulações de Linfócitos/citologia , Linfócitos T Auxiliares-Indutores/citologia
7.
J Immunol ; 168(5): 2212-8, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11859107

RESUMO

Despite the effects of glucocorticoids on immune function, relatively little is known about glucocorticoid-inducible genes and how their products may regulate lymphocyte function. Using DNA microarray technology to analyze gene expression in PBMC from healthy donors, we identified IL-7Ralpha as a glucocorticoid-inducible gene. This observation was confirmed at the mRNA and protein levels. Conversely, TCR signaling decreased IL-7Ralpha expression, and the relative strength of signaling between these two receptors determined the final IL-7Ralpha levels. The up-regulation of IL-7Ralpha by glucocorticoids was associated with enhanced IL-7-mediated signaling and function. Moreover, IL-7-mediated inhibition of apoptosis at increasing concentrations of glucocorticoids is consistent with enhanced cell sensitivity to IL-7 following glucocorticoid exposure. These observations provide a mechanism by which glucocorticoids may have a positive influence on T cell survival and function.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Receptores de Interleucina-7/biossíntese , Linfócitos T/imunologia , Regulação para Cima , Apoptose/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Interleucina-7/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/biossíntese , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Interleucina-2/metabolismo , Receptores de Interleucina-7/genética , Linfócitos T/efeitos dos fármacos , Ativação Transcricional
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