98 research outputs found

    The Role of Cytokines which Signal through the Common γ Chain Cytokine Receptor in the Reversal of HIV Specific CD4(+) and CD8(+) T Cell Anergy

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    BACKGROUND: HIV specific T cells are putatively anergic in vivo. IL-2, a member of a class of cytokines that binds to receptors containing the common gamma chain (γc) has been shown to reverse anergy. We examined the role of γc cytokines in reversing HIV specific T cell anergy. METHODS: PBMC from untreated HIV-infected individuals were briefly exposed to a panel of γc cytokines, and frequencies of gag specific T cells were enumerated by intracellular IFN-γ flow cytometry. RESULTS: Of the γc cytokines, brief exposure to IL-2, IL-15, or combined IL-15/IL-7 significantly enhanced (range 2–7 fold) the CD4(+) and CD8(+) T cell IFN-γ responses to HIV gag, with IL-15 giving the greatest enhancement. The effects of cytokines were not due to enhanced proliferation of pre-existing antigen specific cells, but were due to a combination of enhanced cytokine production from antigen specific T cells plus activation of non-epitope specific T cells. CONCLUSIONS: These observations support the notion that a significant number of HIV specific T cells are circulating in an anergic state. IL-2, IL-7 and particularly IL-15 as an immune modulator to reverse HIV-1 specific T cell anergy should be investigated, with the caveat that non-specific activation of T cells may also be induced

    Racial and ethnic differences in personal cervical cancer screening amongst post-graduate physicians: Results from a cross-sectional survey

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    <p>Abstract</p> <p>Background</p> <p>Racial and ethnic disparities in cervical cancer screening have been attributed to socioeconomic, insurance, and cultural differences. Our objective was to explore racial and ethnic differences in adherence to cervical cancer screening recommendations among female post-graduate physicians.</p> <p>Methods</p> <p>We conducted a cross-sectional survey at one university hospital among a convenience sample of 204 female post-graduate physicians (52% of all potential participants), examining adherence to United States Preventive Services Task Force cervical cancer screening recommendations, perception of adherence to recommendations, and barriers to obtaining care.</p> <p>Results</p> <p>Overall, 83% of women were adherent to screening recommendations and 84% accurately perceived adherence or non-adherence. Women who self-identified as Asian were significantly less adherent when compared with women who self-identified as white (69% vs. 87%; Relative Risk [RR] = 0.79, 95% Confidence Interval [CI], 0.64–0.97; P < 0.01). Women who self-identified as East Indian were significantly less likely to accurately perceive adherence or non-adherence when compared to women who self-identified as white (64% vs. 88%; RR = 0.73, 95% CI, 0.49–1.09, P = 0.04). Women who self-identified as Asian were significantly more likely to report any barrier to obtaining care when compared with women who self-identified as white (60% vs. 35%; RR = 1.75, 95% CI, 1.24–2.47; P = 0.001) and there was a non-significant tendency toward women who self-identified as East Indian being more likely to report any barrier to obtaining care when compared with women who self-identified as white (60% vs. 34%; RR = 1.74, 95% CI, 1.06–2.83; P = 0.06).</p> <p>Conclusion</p> <p>Among a small group of insured, highly-educated physicians who have access to health care, we found racial and ethnic differences in adherence to cervical cancer screening recommendations, suggesting that culture may play a role in cervical cancer screening.</p

    The prevalence of BRCA1 mutations among young women with triple-negative breast cancer

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    <p>Abstract</p> <p>Background</p> <p>Molecular screening for BRCA1 and BRCA2 mutations is now an established component of risk evaluation and management of familial breast cancer. Features of hereditary breast cancer include an early age-of-onset and over-representation of the 'triple-negative' phenotype (negative for estrogen-receptor, progesterone-receptor and HER2). The decision to offer genetic testing to a breast cancer patient is usually based on her family history, but in the absence of a family history of cancer, some women may qualify for testing based on the age-of-onset and/or the pathologic features of the breast cancer.</p> <p>Methods</p> <p>We studied 54 women who were diagnosed with high-grade, triple-negative invasive breast cancer at or before age 40. These women were selected for study because they had little or no family history of breast or ovarian cancer and they did not qualify for genetic testing using conventional family history criteria. BRCA1 screening was performed using a combination of fluorescent multiplexed-PCR analysis, BRCA1 exon-13 6 kb duplication screening, the protein truncation test (PTT) and fluorescent multiplexed denaturing gradient gel electrophoresis (DGGE). All coding exons of BRCA1 were screened. The two large exons of BRCA2 were also screened using PTT. All mutations were confirmed with direct sequencing.</p> <p>Results</p> <p>Five deleterious BRCA1 mutations and one deleterious BRCA2 mutation were identified in the 54 patients with early-onset, triple-negative breast cancer (11%).</p> <p>Conclusion</p> <p>Women with early-onset triple-negative breast cancer are candidates for genetic testing for BRCA1, even in the absence of a family history of breast or ovarian cancer.</p

    The Contribution of Cancer Incidence, Stage at Diagnosis and Survival to Racial Differences in Years of Life Expectancy

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    African Americans have higher cancer mortality rates than whites. Understanding the relative contribution of cancer incidence, stage at diagnosis and survival after diagnosis to the racial gap in life expectancy has important implications for directing future health disparity interventions toward cancer prevention, screening and treatment. We estimated the degree to which higher cancer mortality among African Americans is due to higher incidence rates, later stage at diagnosis or worse survival after diagnosis. Stochastic model of cancer incidence and survival after diagnosis. Surveillance and Epidemiology End Result cancer registry and National Health Interview Survey data. Life expectancy if African Americans had the same cancer incidence, stage and survival after diagnosis as white adults. African-American men and women live 1.47 and 0.91 fewer years, respectively, than whites as the result of all cancers combined. Among men, racial differences in cancer incidence, stage at diagnosis and survival after diagnosis account for 1.12 (95% CI: 0.52 to 1.36), 0.17 (95% CI: −0.03 to 0.33) and 0.21 (95% CI: 0.05 to 0.34) years of the racial gap in life expectancy, respectively. Among women, incidence, stage and survival after diagnosis account for 0.41 (95% CI: −0.29 to 0.60), 0.26 (95% CI: −0.06 to 0.40) and 0.31 (95% CI: 0.05 to 0.40) years, respectively. Differences in stage had a smaller impact on the life expectancy gap compared with the impact of incidence. Differences in cancer survival after diagnosis had a significant impact for only two cancers—breast (0.14 years; 95% CI: 0.05 to 0.16) and prostate (0.05 years; 95% CI 0.01 to 0.09). In addition to breast and colorectal cancer screening, national efforts to reduce disparities in life expectancy should also target cancer prevention, perhaps through smoking cessation, and differences in survival after diagnosis among persons with breast and prostate cancer

    In Vivo Gene Knockdown in Rat Dorsal Root Ganglia Mediated by Self-Complementary Adeno-Associated Virus Serotype 5 Following Intrathecal Delivery

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    We report here in adult rat viral vector mediate-gene knockdown in the primary sensory neurons and the associated cellular and behavior consequences. Self-complementary adeno-associated virus serotype 5 (AAV5) was constructed to express green fluorescent protein (GFP) and a small interfering RNA (siRNA) targeting mammalian target of rapamycin (mTOR). The AAV vectors were injected via an intrathecal catheter. We observed profound GFP expression in lumbar DRG neurons beginning at 2-week post-injection. Of those neurons, over 85% were large to medium-diameter and co-labeled with NF200, a marker for myelinated fibers. Western blotting of mTOR revealed an 80% reduction in the lumbar DRGs (L4–L6) of rats treated with the active siRNA vectors compared to the control siRNA vector. Gene knockdown became apparent as early as 7-day post-injection and lasted for at least 5 weeks. Importantly, mTOR knockdown occurred in large (NF200) and small-diameter neurons (nociceptors). The viral administration induced an increase of Iba1 immunoreactivity in the DRGs, which was likely attributed to the expression of GFP but not siRNA. Rats with mTOR knockdown in DRG neurons showed normal general behavior and unaltered responses to noxious stimuli. In conclusion, intrathecal AAV5 is a highly efficient vehicle to deliver siRNA and generate gene knockdown in DRG neurons. This will be valuable for both basic research and clinic intervention of diseases involving primary sensory neurons

    Factors that could explain the increasing prevalence of type 2 diabetes among adults in a Canadian province: a critical review and analysis

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    Abstract: Background: The prevalence of diabetes has increased since the last decade in New Brunswick. Identifying factors contributing to the increase in diabetes prevalence will help inform an action plan to manage the condition. The objective was to describe factors that could explain the increasing prevalence of type 2 diabetes in New Brunswick since 2001. Methods: A critical literature review was conducted to identify factors potentially responsible for an increase in prevalence of diabetes. Data from various sources were obtained to draw a repeated cross-sectional (2001–2014) description of these factors concurrently with changes in the prevalence of type 2 diabetes in New Brunswick. Linear regressions, Poisson regressions and Cochran Armitage analysis were used to describe relationships between these factors and time. Results: Factors identified in the review were summarized in five categories: individual-level risk factors, environmental risk factors, evolution of the disease, detection effect and global changes. The prevalence of type 2 diabetes has increased by 120% between 2001 and 2014. The prevalence of obesity, hypertension, prediabetes, alcohol consumption, immigration and urbanization increased during the study period and the consumption of fruits and vegetables decreased which could represent potential factors of the increasing prevalence of type 2 diabetes. Physical activity, smoking, socioeconomic status and education did not present trends that could explain the increasing prevalence of type 2 diabetes. During the study period, the mortality rate and the conversion rate from prediabetes to diabetes decreased and the incidence rate increased. Suggestion of a detection effect was also present as the number of people tested increased while the HbA1c and the age at detection decreased. Period and birth cohort effect were also noted through a rise in the prevalence of type 2 diabetes across all age groups, but greater increases were observed among the younger cohorts. Conclusions: This study presents a comprehensive overview of factors potentially responsible for population level changes in prevalence of type 2 diabetes. Recent increases in type 2 diabetes in New Brunswick may be attributable to a combination of some individual-level and environmental risk factors, the detection effect, the evolution of the disease and global changes

    What works for whom in the management of diabetes in people living with dementia: a realist review

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    Background Dementia and diabetes mellitus are common long-term conditions and co-exist in a large number of older people. People living with dementia (PLWD) may be less able to manage their diabetes, putting them at increased risk of complications such as hypoglycaemia. The aim of this review was to identify key mechanisms within different interventions that are likely to improve diabetes outcomes in PLWD. Methods This is a realist review involving scoping of the literature and stakeholder interviews to develop theoretical explanations of how interventions might work, systematic searches of the evidence to test and develop the theories and their validation with a purposive sample of stakeholders. Twenty-six stakeholders — user/patient representatives, dementia care providers, clinicians specialising in diabetes or dementia and researchers — took part in interviews, and 24 participated in a consensus conference. Results We included 89 papers. Ten focused on PLWD and diabetes, and the remainder related to people with either dementia, diabetes or other long-term conditions. We identified six context-mechanism-outcome configurations which provide an explanatory account of how interventions might work to improve the management of diabetes in PLWD. This includes embedding positive attitudes towards PLWD, person-centred approaches to care planning, developing skills to provide tailored and flexible care, regular contact, family engagement and usability of assistive devices. An overarching contingency emerged concerning the synergy between an intervention strategy, the dementia trajectory and social and environmental factors, especially family involvement. Conclusions Evidence highlighted the need for personalised care, continuity and family-centred approaches, although there was limited evidence that this happens routinely. This review suggests there is a need for a flexible service model that prioritises quality of life, independence and patient and carer priorities. Future research on the management of diabetes in older people with complex health needs, including those with dementia, needs to look at how organisational structures and workforce development can be better aligned to their needs. Trial registration PROSPERO, CRD42015020625. Registered on 18 May 2015

    Associations Between Neighborhood-Level Factors Related to a Healthful Lifestyle and Dietary Intake, Physical Activity, and Support for Obesity Prevention Polices Among Rural Adults

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    PURPOSE: To examine cross-sectional associations among neighborhood- and individual-level factors related to a healthful lifestyle and dietary intake, physical activity (PA), and support for obesity prevention polices in rural eastern North Carolina adults. METHODS: We examined perceived neighborhood barriers to a healthful lifestyle, and associations between neighborhood barriers to healthy eating and PA, participants’ support for seven obesity prevention policies, and dependent variables of self-reported dietary and PA behaviors, and measured body mass index (BMI) (n = 366 study participants). We then used participants’ residential addresses and Geographic Information Systems (GIS) software to assess neighborhood-level factors related to access to healthy food and PA opportunities. Correlational analyses and adjusted linear regression models were used to examine associations between neighborhood-level factors related to a healthful lifestyle and dietary and PA behaviors, BMI, and obesity prevention policy support. RESULTS: The most commonly reported neighborhood barriers (from a list of 18 potential barriers) perceived by participants included: not enough bicycle lanes and sidewalks, not enough affordable exercise places, too much crime, and no place to buy a quick, healthy meal to go. Higher diet quality was inversely related to perceived and GIS-assessed neighborhood nutrition barriers. There were no significant associations between neighborhood barriers and PA. More perceived neighborhood barriers were positively associated with BMI. Support for obesity prevention policy change was positively associated with perceptions of more neighborhood barriers. CONCLUSIONS: Neighborhood factors that promote a healthful lifestyle were associated with higher diet quality and lower BMI. Individuals who perceived more neighborhood-level barriers to healthy eating and PA usually supported policies to address those barriers. Future studies should examine mechanisms to garner such support for health-promoting neighborhood changes
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