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1.
PLoS Pathog ; 6(3): e1000798, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20221423

RESUMO

The prevailing paradigm of T lymphocyte control of viral replication is that the protective capacity of virus-specific CD8(+) T cells is directly proportional to the number of functions they can perform, with IL-2 production capacity considered critical. Having recently defined rapid perforin upregulation as a novel effector function of antigen-specific CD8(+) T cells, here we sought to determine whether new perforin production is a component of polyfunctional CD8(+) T cell responses that contributes to the control of several human viral infections: cytomegalovirus (CMV), Epstein-Barr virus (EBV), influenza (flu), and adenovirus (Ad). We stimulated normal human donor PBMC with synthetic peptides whose amino acid sequences correspond to defined CTL epitopes in the aforementioned viruses, and then used polychromatic flow cytometry to measure the functional capacity and the phenotype of the responding CD8(+) T cells. While EBV and flu-specific CD8(+) T cells rarely upregulate perforin, CMV-specific cells often do and Ad stimulates an exceptionally strong perforin response. The differential propensity of CD8(+) T cells to produce either IL-2 or perforin is in part related to levels of CD28 and the transcription factor T-bet, as CD8(+) T cells that rapidly upregulate perforin harbor high levels of T-bet and those producing IL-2 express high amounts of CD28. Thus, "polyfunctional" profiling of antigen-specific CD8(+) T cells must not be limited to simply the number of functions the cell can perform, or one particular memory phenotype, but should actually define which combinations of memory markers and functions are relevant in each pathogenic context.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Interleucina-2/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Viroses/imunologia , Antígenos CD28/imunologia , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Infecções por Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Humanos , Memória Imunológica/imunologia , Imunofenotipagem , Influenza Humana/imunologia , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-2/imunologia , Ativação Linfocitária/imunologia , Perforina , Proteínas Citotóxicas Formadoras de Poros/imunologia , Proteínas com Domínio T/imunologia , Proteínas com Domínio T/metabolismo , Regulação para Cima/imunologia
2.
Clin Nurse Spec ; 32(3): 129-138, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29621108

RESUMO

PURPOSE/AIMS: It is important for seniors to engage in positive health behaviors to reduce the incidence of health-related consequences associated with aging. The purpose of this research study was to examine self-perceived changes in physical activity, nutrition, and alcohol consumption behaviors of seniors living in a retirement home through consideration of previous behaviors and self-perceptions of behavior changes. DESIGN: A qualitative research design was used for this study. METHODS: Semistructured one-on-one interviews were conducted with 9 Canadian women living in a retirement home. RESULTS: Two key themes, each with 3 subthemes, highlighted the various factors that influenced changes in health behaviors. The 2 themes consisted of (a) aging and adapting and (b) the transition: give a little to gain a lot. CONCLUSIONS: Participants' insights revealed the importance of maintaining a positive attitude, the influence of the social environment on health behaviors, and the nutritional sacrifices of retirement living. Future research should investigate ways in which nurses can assist seniors in enhancing health behaviors throughout transitions into retirement homes.


Assuntos
Comportamentos Relacionados com a Saúde , Instituição de Longa Permanência para Idosos , Casas de Saúde , Autoimagem , Idoso , Idoso de 80 Anos ou mais , Canadá , Feminino , Humanos , Pesquisa Qualitativa
3.
J Rural Health ; 34 Suppl 1: s30-s38, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28075508

RESUMO

PURPOSE: The increase in use of health information technologies (HIT) presents new opportunities for patient engagement and self-management. Patients in rural areas stand to benefit especially from increased access to health care tools and electronic communication with providers. We assessed the adoption of 4 HIT tools over time by rural or urban residency. METHODS: Analyses were conducted using data from 7 iterations of the National Cancer Institute's Health Information National Trends Survey (HINTS; 2003-2014). Rural/urban residency was based on the USDA's 2003 Rural-Urban Continuum Codes. Outcomes of interest included managing personal health information online; whether providers maintain electronic health records (EHRs); e-mailing health care providers; and purchasing medicine online. Bivariate analyses and logistic regression were used to assess relationships between geography and outcomes, controlling for sociodemographic characteristics. FINDINGS: In total, 6,043 (17.6%, weighted) of the 33,749 respondents across the 7 administrations of HINTS lived in rural areas. Rural participants were less likely to report regular access to Internet (OR = 0.70, 95% CI = 0.61-0.80). Rural respondents were neither more nor less likely to report that their health care providers maintained EHRs than were urban respondents; however, they had decreased odds of managing personal health information online (OR = 0.59, 95% CI = 0.40-0.78) and e-mailing health care providers (OR = 0.62, 95% CI = 0.49-0.77). CONCLUSIONS: The digital divide between rural and urban residents extends to HIT. Additional investigation is needed to determine whether the decreased use of HIT may be due to lack of Internet connectivity or awareness of these tools.


Assuntos
Registros Eletrônicos de Saúde/provisão & distribuição , Acessibilidade aos Serviços de Saúde/normas , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Registros de Saúde Pessoal , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estados Unidos
4.
J Immunol Methods ; 369(1-2): 33-41, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21501617

RESUMO

Current technology to isolate viable cytokine-producing antigen-specific primary human T cells is limited to bi-specific antibody capture systems, which suffer from limited sensitivity and high background. Here, we describe a novel procedure for isolating antigen-specific human T cells based on their ability to produce tumor necrosis factor (TNF)-α. Unlike many cytokines, TNF-α is initially produced in a biologically active membrane-bound form that is subsequently cleaved by TNF-α converting enzyme (TACE) to release the soluble form of TNF-α. By preventing this cleavage event, we show that TNF-α can be 'trapped' on the surface of the T cells from which it originates and directly labeled for viable isolation of these antigen-specific T cells. Together with other existing sorting procedures to isolate activated T cells, this new technique should permit the direct isolation of multi-functional T lymphocytes for further protein and gene expression analyses, as well as a detailed functional assessment of the potential role that TNF-α producing T cells play in the adaptive immune system.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Separação Celular/métodos , Fator de Necrose Tumoral alfa/imunologia , Linfócitos T CD8-Positivos/metabolismo , Membrana Celular , Células Cultivadas , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Células Matadoras Naturais/imunologia , Fator de Necrose Tumoral alfa/metabolismo
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