997 resultados para Chronic


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Background Chromosomal translocations resulting in alternative fusions of the human TEL (ETV6) and JAK2 genes have been observed in cases of acute lymphoblastic leukemia and chronic myelogenous leukemia, but a full understanding of their role in disease etiology has remained elusive. In this study potential differences between these alternative TEL-JAK2 fusions, including their lineage specificity, were investigated.

Design and Methods TEL-JAK2 fusion types derived from both T-cell acute lymphoblastic leukemia and atypical chronic myelogenous leukemia were generated using the corresponding zebrafish tel and jak2a genes and placed under the control of either the white blood cell-specific spi1 promoter or the ubiquitously-expressed cytomegalovirus promoter. These constructs were injected into zebrafish embryos and their effects on hematopoiesis examined using a range of molecular approaches. In addition, the functional properties of the alternative fusions were investigated in vitro.

Results Injection of the T-cell acute lymphoblastic leukemia-derived tel-jak2a significantly perturbed lymphopoiesis with a lesser effect on myelopoiesis in zebrafish embryos. In contrast, injection of the atypical chronic myelogenous leukemia-derived tel-jak2a resulted in significant perturbation of the myeloid compartment. These phenotypes were observed regardless of whether expressed in a white blood cell-specific or ubiquitous manner, with no overt cellular proliferation outside of the hematopoietic cells. Functional studies revealed subtle differences between the alternative forms, with the acute lymphoblastic leukemia variant showing higher activity, but reduced downstream signal transducer and activator of transcription activation and decreased sensitivity to JAK2 inhibition. JAK2 activity was required to mediate the effects of both variants on zebrafish hematopoiesis.

Conclusions This study indicates that the molecular structure of alternative TEL-JAK2 fusions likely contributes to the etiology of disease. The data further suggest that this class of oncogene exerts its effects in a cell lineage-specific manner, which may be due to differences in downstream signaling.

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This qualitative study describes the understanding of health and belief practices among elderly Greek Australians. In particular, the role of religion is discussed as a means of resilience and adjustment to illness, as religious faith often influences individual’s thoughts, feelings, and how they may accept or understand their particular health condition. Adjustment has a strong psychological or emotional component that is likely to be affected by culturally determined conceptualizations of health. As such, the particular background of a population may be very significant in the level and means of adaptation of individuals and groups.

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Background and objective: Natural killer (NK) and natural killer T (NKT)-like cells represent a small but important proportion of effector lymphocytes that we have previously shown to be major sources of pro-inflammatory cytokines and granzymes. We hypothesized that these cells would be increased in the airway in chronic obstructive pulmonary disease (COPD), accompanied by reduced expression of the inhibitory receptor CD94 (Kp43) and increased expression of cytotoxic mediators granzyme B and perforin.
Methods: We measured NK and NKT-like cells and their expression of CD94 in the blood of COPD patients (n = 71; 30 current and 41 ex-smokers), smokers (16) and healthy controls (25), and bronchoalveolar lavage fluid (BALF) from a cohort of subjects (19 controls, 12 smokers, 33 COPD). Activation was assessed by measuring CD69 in blood and the cytotoxic potential of NK cells by measuring granzymes A and B, and using a cytotoxicity assay in blood and BALF.
Results: In blood in COPD, there were no significant changes in the proportion of NK or NKT-like cells or expression of granzyme A or NK cytotoxic potential versus controls. There was, however, increased expression of granzyme B and decreased expression of CD94 by both cell types versus controls. The proportion of NK and NKT-like cells were increased in BALF in COPD, associated with increased NK cytotoxicity, increased expression of granzyme B and decreased expression of the inhibitory receptor CD94 by both cell types.
Conclusions: Treatment strategies that target NK and NKT-like cells, their cytotoxicity and production of inflammatory mediators in the airway may improve COPD morbidity.

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Objectives: 

To provide an in-depth analysis of outcome measures used in the evaluation of chronic disease self-management programs consistent with the Stanford curricula.

Methods:
Based on a systematic review on self-management programs, effect sizes derived from reported outcome measures are categorized according to the quality of life appraisal model developed by Schwartz and Rapkin which classifies outcomes from performance-based measures (e.g., clinical outcomes) to evaluation-based measures (e.g., emotional well-being).

Results:
The majority of outcomes assessed in self-management trials are based on evaluation-based methods. Overall, effects on knowledge—the only performance-based measure observed in selected trials—are generally medium to large. In contrast, substantially more inconsistent results are found for both perception- and evaluation-based measures that mostly range between nil and small positive effects.

Conclusions:
Effectiveness of self-management interventions and resulting recommendations for health policy makers are most frequently derived from highly variable evaluation-based measures, that is, types of outcomes that potentially carry a substantial amount of measurement error and/or bias such as response shift. Therefore, decisions regarding the value and efficacy of chronic disease self-management programs need to be interpreted with care. More research, especially qualitative studies, is needed to unravel cognitive processes and the role of response shift bias in the measurement of change.

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Purpose
To carry out a systematic review of program outcomes used in the evaluation of group-based self-management interventions aimed at people with arthritis and other chronic conditions.

Methods
The systematic search was performed across databases MEDLINE, EMBASE, CINAHL, and PsycINFO. Both between-group and within-group effect sizes (ES) were calculated. Results were interpreted as small (ES ~ 0.2), medium (ES ~ 0.5), or large (ES ~ 0.8) effects.

Results
The majority of 18 included trials investigated the effectiveness of arthritis-specific interventions. Across most outcomes, small effects on course participants were shown. While effects on knowledge were large (between-group ES = 0.78), effects on clinical outcomes such as pain (ES = 0.10) were negligible to small.

Conclusions
This paper is consistent with other reviews in this area, suggesting that people with arthritis receive only marginal benefits from participating in chronic disease self-management interventions. When looking at the types of outcomes that trials are based on, however, alternative explanations for these results seem probable. As evaluations heavily rely on patient self-report, current approaches to program evaluation may not be sufficient to assess the intended impact of self-management education. An in-depth investigation of the types of outcomes assessed is provided in a separate paper.

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Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease; it is a leading cause of death and existing treatments have no proven disease-modifying effect. The mechanisms underlying this resistance are largely unknown, but suggest the presence of some self-maintaining pathogenic process, possibly initiated by cigarette smoking, that prevents the normal resolution of inflammation. We have previously reported increased production of proinflammatory cytokines and granzyme b by CD8+ T cells in COPD; costimulatory receptor/ligand interactions required include CD80:86/CD28, B7-1/CTLA4, 4-1BB/1BBL and OX40/OX40L. We hypothesized that a dysregulated expression/function of these molecules may play a role in inflammatory/autoimmune components of COPD. We analysed T cell co-stimulatory molecules in blood from 34 controls, 15 smokers and 48 COPD subjects. We assessed the potential functional relevance of CD8/CD28null cells in COPD by measuring their production of proinflammatory cytokines, co-stimulatory molecules, granzyme and perforin. A smoke-exposed murine model was applied to investigate the relative expression of CD8/CD28null T cells in blood, lung tissue and airway. CD8/CD28null cells were increased in both current- and ex-smoker COPD groups; these cells expressed significantly more interferon (IFN)-γ, OX40, 4-1BB, CTLA4, granzyme and perforin when stimulated than CD8/CD28+ T cells. There were no changes in CD4/CD28null T cells. In mice exposed to cigarette smoke for 12 weeks, CD8/CD28null T cells were significantly increased in the airway with a trend for an increase in lung tissue and blood. Increased production of proinflammatory cytokines and expression of alternative co-stimulatory molecules by CD8/CD28null T cells may play a role in inflammatory or autoimmune responses in COPD and identify therapeutic targets.