445 research outputs found

    Clinical relevance of biomarkers of oxidative stress

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    SIGNIFICANCE Oxidative stress is considered to be an important component of various diseases. A vast number of methods have been developed and used in virtually all diseases to measure the extent and nature of oxidative stress, ranging from oxidation of DNA to proteins, lipids, and free amino acids. Recent Advances: An increased understanding of the biology behind diseases and redox biology has led to more specific and sensitive tools to measure oxidative stress markers, which are very diverse and sometimes very low in abundance. CRITICAL ISSUES The literature is very heterogeneous. It is often difficult to draw general conclusions on the significance of oxidative stress biomarkers, as only in a limited proportion of diseases have a range of different biomarkers been used, and different biomarkers have been used to study different diseases. In addition, biomarkers are often measured using nonspecific methods, while specific methodologies are often too sophisticated or laborious for routine clinical use. FUTURE DIRECTIONS Several markers of oxidative stress still represent a viable biomarker opportunity for clinical use. However, positive findings with currently used biomarkers still need to be validated in larger sample sizes and compared with current clinical standards to establish them as clinical diagnostics. It is important to realize that oxidative stress is a nuanced phenomenon that is difficult to characterize, and one biomarker is not necessarily better than others. The vast diversity in oxidative stress between diseases and conditions has to be taken into account when selecting the most appropriate biomarker. Antioxid. Redox Signal. 00, 000-000

    Breast cancer and childhood anthropometry: emerging hypotheses?

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    In this issue of Breast Cancer Research, Baer and colleagues report a strong protective effect of childhood and adolescent body fatness on premenopausal breast cancer risk based on a large prospective study. Methodological issues are discussed, as are tentative biological interpretations regarding the findings

    The Dynamics of Managerial Ideology: Analyzing the Cuban Case

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    After the collapse of state socialism in Eastern Europe, management researchers devoted considerable energy to investigate ways to smooth transition to market economies. But one country of the former Soviet bloc, Cuba resisted transition and reaffirmed loyalty to communism. Little is known about management in Cuba on the managerial impacts of the combination of two major environmental forces: the American embargo and the Soviet Union collapse, both of which have challenged the sustainability of the communist regime. This study intends to approach one particular aspect of management in Cuba: the relationship between national ideology and management practice. To analyze these topics, direct qualitative data from focus groups with Cuban managers and management professors was obtained and complemented with documentary analysis. Results suggest that the dynamics of managerial ideology can be understood as the interplay of several processes operating at distinct levels: institutional, professional, organizational and individual. The study provides a nested, multi-level understanding of management and organization as parts of a wider institutional context, which is both a source of constraint and a non-tangible resource to be used by ideological bricoleurs. The interplay between the acceptance of ideology and its use as a practical resource is a potential source of change. As such, the same professional class (managers) may be both a source of continuity and a trigger of change - a finding that is line with institutional theory’s claim that it is necessary to understand both institutionalization and de-institutionalization for understanding organizational change and continuity.N/

    Identification of Protein Targets of Reactive Metabolites of Tienilic Acid in Human Hepatocytes

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in Chemical Research in Toxicology, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/tx300103jTienilic acid (TA) is a uricosuric diuretic that was withdrawn from the market only months after its introduction because of reports of serious incidents of drug-induced liver injury including some fatalities. Its hepatotoxicity is considered to be primarily immunoallergic in nature. Like other thiophene compounds, TA undergoes biotransformation to a S-oxide metabolite which then reacts covalently with cellular proteins. To identify protein targets of TA metabolites, we incubated [14C]-TA with human hepatocytes, separated cellular proteins by 2D gel electrophoresis, and analyzed proteins in 36 radioactive spots by tryptic digestion followed by LC-MS/MS. Thirty one spots contained at least one identifiable protein. Sixteen spots contained only one of 14 non-redundant proteins which were thus considered to be targets of TA metabolites. Six of the 14 were also found in other radioactive spots that contained from 1 to 3 additional proteins. Eight of the 14 had not been reported to be targets for any reactive metabolite other than TA. The other 15 spots each contained from 2–4 identifiable proteins, many of which are known targets of other chemically reactive metabolites, but since adducted peptides were not observed, the identity of the adducted protein(s) in these spots is ambiguous. Interestingly, all the radioactive spots corresponded to proteins of low abundance, while many highly abundant proteins in the mixture showed no radioactivity. Furthermore, of approximately 16 previously reported protein targets of TA in rat liver (Methogo, R., Dansette, P. and Klarskov, K. (2007) Int. J. Mass Spectrom., 268, 284–295), only one (fumarylacetoacetase) is among the 14 targets identified in this work. One reason for this difference may be statistical, given that each study identified a small number of targets from among thousands present in hepatocytes. Another may be the species difference (i.e. rat vs. human), and still another may be the method of detection of adducted proteins (i.e. Western blot vs. C-14). Knowledge of human target proteins is very limited. Of more than 350 known protein targets of reactive metabolites, only 42 are known from human and only 21 of these are known to be targets for more than one chemical. Nevertheless, the demonstration that human target proteins can be identified using isolated hepatocytes in vitro should enable the question of species differences to be addressed more fully in the future

    Rationale and design of the EMPERIAL-Preserved and EMPERIAL-Reduced trials of empagliflozin in patients with chronic heart failure

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    Aims: Heart failure (HF) is associated with considerable symptom burden and impairment in physical functioning and quality of life. The sodium–glucose co-transporter 2 inhibitor empagliflozin reduced the risk of HF hospitalisation and cardiovascular death in patients with type 2 diabetes and established cardiovascular disease in the EMPA-REG OUTCOME trial, and could potentially improve congestion symptoms and exercise capacity in patients with HF. We describe the designs of the EMPERIAL-Preserved and EMPERIAL-Reduced trials of empagliflozin in patients with chronic stable HF, with or without type 2 diabetes. Methods: EMPERIAL-Preserved and EMPERIAL-Reduced are randomised, placebo-controlled trials designed to investigate the effects of empagliflozin on exercise capacity and patient-reported outcomes in patients with chronic stable HF with preserved ejection fraction [HFpEF; left ventricular ejection fraction (LVEF) > 40%] and HF with reduced ejection fraction (HFrEF; LVEF ≤ 40%), respectively. In each trial, approximately 300 patients will be randomised 1:1 to receive empagliflozin 10 mg or placebo once daily for 12 weeks. In both trials, the primary endpoint is the change from baseline in 6-min walk test distance at week 12. Key secondary endpoints are the change from baseline in Kansas City Cardiomyopathy Questionnaire total symptom score and change from baseline in dyspnoea score of the Chronic Heart Failure Questionnaire at week 12. Conclusion: The EMPERIAL-Preserved and EMPERIAL-Reduced trials will determine the effects of empagliflozin on exercise capacity and patient-reported outcomes in patients with HFpEF and HFrEF, respectively, and provide insight into the potential of empagliflozin in the treatment of patients with HF. Clinical Trial Registration: ClinicalTrials.gov ID: NCT03448406 (EMPERIAL-Preserved), NCT03448419 (EMPERIAL-Reduced). (EMPERIAL Investigators) (Natl Coordinators

    Evaluating real-time internet therapy and online self-help for problematic alcohol consumers: a three-arm RCT protocol

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    <p>Abstract</p> <p>Background</p> <p>Only a minority of all alcohol- and drug abusers is receiving professional care. In an attempt to narrow this treatment gap, treatment facilities experiment with online healthcare. Therefore, it is important to test the (cost-)effectiveness of online health interventions in a randomized clinical trial.</p> <p>Methods</p> <p>This paper presents the protocol of a three-arm randomized clinical trial to test the (cost-) effectiveness of online treatment for problem drinkers. Self-help online, therapy online and a waiting list are tested against each other. Primary outcome is change in alcohol consumption. Secondary outcome measures include quality of life and working ability. Incremental cost-effectiveness ratios for self-help online alcohol and therapy online alcohol will be calculated. The predictive validity of participant characteristics on treatment adherence and outcome will be explored.</p> <p>Discussion</p> <p>To our best knowledge, this randomized clinical trial will be the first to test the effectiveness of therapy online against both self-help online and a waiting-list. It will provide evidence on (cost-) effectiveness of online treatment for problem drinkers and investigate outcome predictors.</p> <p>Trial registration</p> <p>This trial is registered in the Dutch Trialregister (Cochrane Collaboration) and traceable as NTR-TC1155.</p
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