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1.
Health Educ Res ; 38(3): 193-203, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36718591

RESUMO

Health-care professionals (HCPs) are key trusted figures in addressing coronavirus disease 2019 (COVID-19) challenges. They are thought to influence others' health decisions by personal example. However, during the COVID-19 crisis, some HCPs hesitated to be vaccinated. We examined factors contributing to that decision. We performed 12 semi-structured interviews, between February and May 2021, with Israeli HCPs who had declined or delayed COVID-19 vaccination. Three coders conducted a combined top-down and bottom-up analysis. We identified four main themes shaping vaccine decision-making: (i) sources of information, (ii) perceptions of necessity and risks of the vaccine, (iii) individual versus collective responsibility and (iv) political climate and media influence. Participants were worried about long-term effectiveness and safety, and while many agreed that high-risk populations should be vaccinated, all considered themselves to be at low risk for serious disease. Some felt they should avoid taking a perceived risk (accepting a new vaccine) to protect society, although they felt pressured to do so. Vaccination campaign politization and the way the media approached the subject also contributed to mistrust and hesitancy to be vaccinated. These findings help us understand HCP beliefs and uncertainties about COVID-19 vaccinations. This study can help inform future campaigns targeted at HCPs to promote the acceptance of vaccines.


Assuntos
COVID-19 , Vacinas , Humanos , Hesitação Vacinal , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Emoções , Pessoal de Saúde , Vacinação
2.
Int J Mol Sci ; 23(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35628565

RESUMO

Mesenchymal stem cells (MSC) have many roles that are important for the body's proper functioning. When the MSC pool is damaged, it is often correlated with impaired development or health of the organism. MSC are known for their anti-inflammatory, immunomodulatory and trophic characteristics that play an important role in the physiological homeostasis of many tissues. Heat shock impairs MSC capacity by inducing the generation of reactive oxygen species and mitochondrial dysfunction, which, in turn, send the cells into a state of premature senescence. Here, we pre-exposed MSC to melatonin, resveratrol, or curcumin, which are natural antioxidative compounds, and tested the protective effects of these substances from oxidative stress and aging. Our data showed that pre-exposure of MSC to antioxidants decreased reactive oxygen species while mitochondrial damage remained high. Additionally, although the proliferation of the cells was slow, antioxidants protected the cells from premature senescence, and subsequent cytokine release was prevented. We conclude that while elevated temperatures directly cause mitochondrial damage, senescence is induced by elevated ROS levels. We suggest that heat shock alters cell and tissue homeostasis by several independent mechanisms; however, reducing tissue senescence will reduce damage and provide a pathway to overcome physiological challenges in animals.


Assuntos
Antioxidantes , Células-Tronco Mesenquimais , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Bovinos , Senescência Celular , Resposta ao Choque Térmico , Células-Tronco Mesenquimais/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Proc Natl Acad Sci U S A ; 113(12): E1673-82, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-26862173

RESUMO

Mitochondria are major suppliers of cellular energy through nutrients oxidation. Little is known about the mechanisms that enable mitochondria to cope with changes in nutrient supply and energy demand that naturally occur throughout the day. To address this question, we applied MS-based quantitative proteomics on isolated mitochondria from mice killed throughout the day and identified extensive oscillations in the mitochondrial proteome. Remarkably, the majority of cycling mitochondrial proteins peaked during the early light phase. We found that rate-limiting mitochondrial enzymes that process lipids and carbohydrates accumulate in a diurnal manner and are dependent on the clock proteins PER1/2. In this conjuncture, we uncovered daily oscillations in mitochondrial respiration that peak during different times of the day in response to different nutrients. Notably, the diurnal regulation of mitochondrial respiration was blunted in mice lacking PER1/2 or on a high-fat diet. We propose that PERIOD proteins optimize mitochondrial metabolism to daily changes in energy supply/demand and thereby, serve as a rheostat for mitochondrial nutrient utilization.


Assuntos
Ritmo Circadiano/fisiologia , Mitocôndrias Hepáticas/fisiologia , Proteínas Mitocondriais/metabolismo , Proteínas Circadianas Period/fisiologia , Animais , Ritmo Circadiano/genética , Ciclo do Ácido Cítrico , Dieta Hiperlipídica , Gorduras na Dieta/metabolismo , Transporte de Elétrons , Ácidos Graxos/metabolismo , Comportamento Alimentar/fisiologia , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias Hepáticas/enzimologia , Atividade Motora , Proteínas Circadianas Period/deficiência , Proteínas Circadianas Period/genética , Proteoma , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
4.
J Sci Med Sport ; 26(6): 291-295, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36997416

RESUMO

OBJECTIVES: To assess the status at 13 to 17 years follow-up of a cohort of young male traumatic shoulder dislocators. STUDY DESIGN: Prospective cohort study. METHODS: A prospective study of first-time young male traumatic shoulder dislocators, began in 2004. Subjects were evaluated by the apprehension test after completing rehabilitation 6 to 9 weeks post dislocation. Between March 2021 and July 2022, a telephone questionnaire was administered to ascertain their current shoulder status. Subjects were questioned about avoidance of activities of daily living and sport, participation in sports, current instability, and self-assessed shoulder function by the SANE score. RESULTS: 50/53 (94.3%) of the study subjects, mean age 20.4 years, completed a mean follow-up of 181.8 ±â€¯12 months. The non-redislocation survival was 13% for those with a positive apprehension test and 49% for those with a negative test (p = 0.007). SANE scores were 64.3 ±â€¯23.7 for those with a positive apprehension test and 83.7 ±â€¯19.7 for those with a negative test (p = 0.001). In the year before the follow-up, 33.3% of those treated conservatively and 42.9% treated surgically experienced subluxation (p = 0.5). Fifty-seven percent of those who were treated conservatively and 56% of those who underwent surgery avoided some ADL or sports because of their shoulder. CONCLUSIONS: For young male first time traumatic shoulder dislocators a positive apprehension test after rehabilitation is associated with a high risk for reoccurrence and poorer long-term results. Most subjects were still dealing with shoulder symptoms at long-term follow-up.


Assuntos
Luxações Articulares , Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Humanos , Masculino , Adulto Jovem , Adulto , Luxação do Ombro/diagnóstico , Luxação do Ombro/cirurgia , Seguimentos , Ombro , Estudos Prospectivos , Atividades Cotidianas , Instabilidade Articular/diagnóstico , Recidiva , Artroscopia , Estudos Retrospectivos
5.
Front Cell Dev Biol ; 8: 565970, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072750

RESUMO

Heat stress can have a serious impact on the health of both humans and animals. A major question is how heat stress affects normal development and differentiation at both the cellular and the organism levels. Here we use an in vitro experimental system to address how heat shock treatment influences the properties of bovine mesenchymal stem cells (MSCs)-multipotent progenitor cells-which are found in most tissues. Because cattle are sensitive to harsh external temperatures, studying the effects of heat shock on MSCs provides a unique platform to address cellular stress in a physiologically relevant model organism. Following isolation and characterization of MSCs from the cow's umbilical cord, heat shock was induced either as a pulse (1 h) or continuously (3 days), and consequent effects on MSCs were characterized. Heat shock induced extensive phenotypic changes in MSCs and dramatically curtailed their capacity to proliferate and differentiate. These changes were associated with a partial arrest in the G1/S or G2/M checkpoints. Furthermore, MSCs lost their ability to resolve the inflammatory response of RAW macrophages in coculture. A possible explanation for this loss of function is the accumulation of reactive oxygen species and malfunction of the mitochondria in the treated cells. Heat shock treatments resulted in stress-induced premature senescence, affecting the MSCs' ability to proliferate properly for many cell passages to follow. Exposure to elevated external temperatures leads to mitochondrial damage and oxidative stress, which in turn conveys critical changes in the proliferation, differentiation, and immunomodulatory phenotype of heat-stressed MSCs. A better understanding of the effect of heat shock on humans and animals may result in important health and economic benefits.

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