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Biomedical subjects

Susan Foster

Publications and source records attributed to Susan Foster.

10 recordsLinked to original sources
PubMed2006

beta-Agonist enhances type 2 T-cell survival and accumulation.

BACKGROUND: Neurohumoral modulation of immune system function is poorly understood. beta-Adrenergic receptor ligands (beta-agonists) subserve numerous physiologic processes but also function as pathogenic or therapeutic agents in numerous diseases with inflammatory components. OBJECTIVES: We sought to establish the effects of beta-agonists and prostaglandin E(2) (PGE(2)) on antigen-dependent and antigen-independent accumulation of IL-13(+) (type 2) and IFN-gamma(+) (type 1) T cells. We also sought to clarify the mechanisms mediating the effects of these G protein-coupled receptor agonists. METHODS: Effects of beta-agonists or PGE(2) on T-cell subtype accumulation were assessed in peripheral blood lymphocytes cultured with alphaCD3/CD28 or IL-2 by using flow cytometry. The role of cyclic AMP-dependent protein kinase (PKA) in mediating agonist effects was assessed by means of characterization of (1) phosphorylation of an intracellular PKA substrate and (2) T cells from patients with lupus possessing a natural defect in PKA activation. RESULTS: beta-Agonists, in contrast to PGE(2), increased IL-2-induced accumulation of human type 2 T cells, an effect attributable to differential activation of PKA affecting regulation of cell proliferation and apoptosis. In T cells from patients with lupus exhibiting defective PKA activation, both beta-agonists and PGE(2) promoted an increase in type 2 T-cell accumulation. CONCLUSION: G(s)-coupled receptors have the capacity to elicit prosurvival signaling in type 2 T cells, which, in most instances, is obscured by concomitant and antimitogenic PKA activation. CLINICAL IMPLICATIONS: beta-Agonists and other G(s)-coupled receptor agonists have the potential to regulate T-cell development to affect disease pathogenesis or the efficacy of therapies, and variability of effect relates to the ability to stimulate PKA activity.

Adrenergic beta-Agonists↗
PubMed2006

The role of community acceptance over time for costs of HIV and STI prevention interventions: analysis of the Masaka Intervention Trial, Uganda, 1996-1999.

OBJECTIVE: The objective of this study is to estimate the annual costs of information, education, and communication (IEC), both community- and school-based; strengthened public and private sexually transmitted infections treatment; condom social marketing (CSM); and voluntary counseling and testing (VCT) implemented in Masaka, Uganda, over 4 years, and to explore how unit costs change with varying population use/uptake. STUDY: Total economic provider's costs and intervention outputs were collected annually to estimate annual unit costs between 1996 and 1999. RESULTS: In early intervention years, uptake of all activities grew dramatically and continued to grow for public STI treatment, CSM, and VCT. Attendance at IEC performances started to drop in year 4. Unit costs dropped rapidly with increasing uptake of and participation in interventions. CONCLUSIONS: When implementing long-term community-based interventions, it is important to take into account that it takes time for communities to scale up their participation, since this can lead to large variations in unit costs.

Advertising↗
PubMed2005

Beta-agonists modulate T-cell functions via direct actions on type 1 and type 2 cells.

Although the beta2-adrenergic receptor (beta2AR) is the most extensively characterized G-protein-coupled receptor (GPCR), the effects of beta-agonists on T-cell subtype function remain poorly understood. In contrast to studies suggesting lack of beta2AR expression on type 2 T cells, we demonstrate that type 2 interleukin-13+ (IL-13+) T cells (CD4+ or CD8+) in human peripheral blood lymphocytes (PBLs) can respond directly to beta-agonist, with effects including induction of protein kinase A (PKA) activity and associated inhibition of CD3-stimulated CD25 expression; CD3-stimulated IL-13, interferon-gamma (IFN-gamma), and IL-2 production; and p38 mitogen-activated protein kinase (MAPK) phosphorylation. PGE2 was more efficacious than beta-agonist in activating PKA and inhibiting cytokine production. beta-agonist and PGE2 also inhibited phorbol myristate acetate (PMA) + calcimycin-stimulated IFN-gamma and IL-2 (but not IL-13) production, suggesting that upstream CD3-initiated signaling is not the sole locus of PKA actions. Differential regulation of PMA-stimulated p38, p42/p44, and NF-kappaB explained the capacity of PGE2 and beta-agonist to inhibit IFN-gamma but not IL-13 production. The inhibition of CD3 + CD28-stimulated IL-13 production by both beta-agonist and PGE2 was reversed at low agonist concentrations, resulting in enhanced IL-13, but not IFN-gamma or IL-2, production. These findings identify direct effects of beta2AR activation on T-cell subtypes and suggest a complex role for GPCRs and PKA activity in modulating T-cell functions.

Adrenergic beta-2 Receptor Agonists↗
PubMed2005

Self-enhancement, crash-risk optimism and the impact of safety advertisements on young drivers.

In Study 1, young drivers (aged between 16 and 29 years, N = 314) rated their driving attributes relative to their peers. They also rated their likelihood of being involved in a crash relative to their peers (crash-risk optimism), their crash history, stereotype of the young driver, and concern over another health issue. A self-enhancement bias was found for all items in which self/other comparisons were made. These items formed two major factors, perceived relative driving ability and perceived relative driving caution. These factors and perceived luck relative to peers in avoiding crashes significantly predicted crash-risk optimism. In Study 2, an experimental group of young drivers (N = 173) watched safety advertisements that showed drinking and dangerous driving resulting in a crash, and a control group (N = 193) watched advertisements showing people choosing not to drive after drinking. Each group then completed the self/other comparisons used in Study 1. The same factors were found, but only driving caution significantly predicted crash-risk optimism. The experimental group showed more self-enhancement on driving ability than the control group. In both studies, men showed substantially more self-enhancement than women about their driving ability. Implications for safety interventions are discussed.

Accidents, Traffic↗
PubMed2004

The role of mentoring relationships in the career development of successful deaf persons.

A qualitative study of deaf graduates of Rochester Institute of Technology in New York State who became supervisors in primarily hearing work settings found that having a mentor was a primary and persistent element in their career success. In the deaf individual's early years, generally it was a family member or teacher who conveyed a belief in that individual's abilities, encouraged effort, and helped instill self-esteem and confidence. Parents were often their strongest advocates, and teachers were their advisors and facilitators. In the work setting, a supervisor or coworker often served as a mentor by coaching, advising, and teaching the individual what they needed to know to succeed on the job. In many ways, these "informal" mentors provided the foundation that enabled the deaf individual to break through what are often barriers to career success despite their skills and abilities. The various forms of mentorship and their impact on deaf college graduates are explored.

Academies and Institutes↗
PubMed2003

Deaf persons of asian american, Hispanic american, and african american backgrounds: a study of intraindividual diversity and identity.

This article explores the ways in which deaf college students who are members of minority racial groups think about and describe their identities. In-depth, semistructured interviews with 33 deaf students of Asian American, Hispanic American, and African American background were analyzed for themes regarding the self-reported identities of respondents. Results suggest that each person is a constellation of many parts, some of which are stronger than others but any of which can be drawn out in response to a particular set of circumstances, resulting in a contextual and interactive model of identity. Four factors are described as central to this "intraindividual" model: individual characteristics, situational conditions, social conditions, and societal conditions. Additionally, the model includes a biographical component reflected in changes in identity that occur over time. Findings are discussed as they relate to identity theory. The article is concluded with recommendations for further research, as well as considerations for educators and counselors of deaf minority students.

Journal Article↗
PubMed2003

Deaf people at work: assessment of communication among deaf and hearing persons in work settings.

This paper focuses on the assessment of communication among deaf and hearing persons within work settings. The paper is organized into two sections. In the first section, findings are presented from an ethnographic study of deaf professionals who have achieved relative success in their employment. The results from this study provide the foundation for a model of communication in work settings, presented in the second section of the paper. This model uses an ecological approach, focusing on assessment of communication at the individual level as it occurs within the broader context of organizational culture, influenced by national trends regarding legal rights, technological advances, and social awareness/attitudes towards deafness.

Adaptation, Psychological↗