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21.
Hyland ME 《Complementary Therapies in Medicine》2003,11(3):146-153
It has been suggested that CAM research should establish efficacy before examining mechanism. This paper shows that the efficacy-mechanism distinction is a false one, as any test of efficacy assumes a particular mechanism and is a test of the theory underlying that mechanism. The term RCT is currently used in medicine for two different sorts of study. The randomised controlled trial (RConT) requires an experimental manipulation that can 'control' for the mechanism under consideration, and therefore tests the efficacy of that mechanism. The randomised comparison trial (RComT) requires only an experimental manipulation creating a therapeutically relevant comparison, and tests the effectiveness of that therapy. The ability to achieve control coupled with an assumed implausibility of hidden moderating variables characterises drug therapy and some CAM therapies where the RConT can be used. However, other CAM researchers assume a variety of holistic mechanisms, where control is necessarily poor and the hypothesis of complex interactions suggest the existence of multiple moderators. In these cases other experimental (e.g. RComT), quasi-experimental or non-experimental designs are needed to evaluate therapeutic practice. Researchers from both communities should make explicit their underlying assumptions and the mechanisms they seek to evaluate when carrying out empirical studies. Research design needs to be appropriate for the mechanism under test. 相似文献
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Suppressor screen in Mpl-/- mice: c-Myb mutation causes supraphysiological production of platelets in the absence of thrombopoietin signaling 下载免费PDF全文
Carpinelli MR Hilton DJ Metcalf D Antonchuk JL Hyland CD Mifsud SL Di Rago L Hilton AA Willson TA Roberts AW Ramsay RG Nicola NA Alexander WS 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(17):6553-6558
Genetic screens in lower organisms, particularly those that identify modifiers of preexisting genetic defects, have been used successfully to order components of complex signaling pathways. To date, similar suppressor screens have not been used in vertebrates. To define the molecular pathways regulating platelet production, we have executed a large-scale modifier screen with genetically thrombocytopenic Mpl(-/-) mice by using N-ethyl-N-nitrosourea mutagenesis. Here we show that mutations in the c-Myb gene cause a myeloproliferative syndrome and supraphysiological expansion of megakaryocyte and platelet production in the absence of thrombopoietin signaling. This screen demonstrates the utility of large-scale N-ethyl-N-nitrosourea mutagenesis suppressor screens in mice for the simultaneous discovery and in vivo validation of targets for therapeutic discovery in diseases for which mouse models are available. 相似文献
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S. E. Sparks C. A. Wassif H. Goodwin S. K. Conley D. C. Lanham L. E. Kratz K. Hyland A. Gropman E. Tierney F. D. Porter 《Journal of inherited metabolic disease》2014,37(3):415-420
Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive, multiple congenital anomaly syndrome with cognitive impairment and a distinct behavioral phenotype that includes autistic features. SLOS is caused by a defect in 3β-hydroxysterol Δ7-reductase which leads to decreased cholesterol levels and elevated cholesterol precursors, specifically 7- and 8-dehydrocholesterol. However, the pathological processes contributing to the neurological abnormalities in SLOS have not been defined. In view of prior data suggesting defects in SLOS in vesicular release and given the association of altered serotonin metabolism with autism, we were interested in measuring neurotransmitter metabolite levels in SLOS to assess their potential to be used as biomarkers in therapeutic trials. We measured cerebral spinal fluid levels of serotonin and dopamine metabolites, 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) respectively, in 21 SLOS subjects. Results were correlated with the SLOS anatomical severity score, Aberrant Behavior Checklist scores and concurrent sterol biochemistry. Cerebral spinal fluid (CSF) levels of both 5HIAA and HVA were significantly reduced in SLOS subjects. In individual patients, the levels of both 5HIAA and HVA were reduced to a similar degree. CSF neurotransmitter metabolite levels did not correlate with either CSF sterols or behavioral measures. This is the first study demonstrating decreased levels of CSF neurotransmitter metabolites in SLOS. We propose that decreased levels of neurotransmitters in SLOS are caused by a sterol-related defect in synaptic vesicle formation and that CSF 5HIAA and HVA will be useful biomarkers in development of future therapeutic trials. 相似文献
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Shing S. T. To Peter M. Newman Valentine J. Hyland Bruce G. Robinson Leslie Schrieber 《Arthritis \u0026amp; Rheumatology》1996,39(3):467-477
Objective. To examine the in vitro expression of E-selectin, P-selectin, intercellular adhesion molecule 1 (ICAM-1), ICAM-2, vascular cell adhesion molecule 1 (VCAM-1), and platelet–endothelial cell adhesion molecule 1 (PECAM-1) by synovial microvascular endothelial cells (SMEC) in comparison with microvascular neonatal foreskin endothelial cells (FSE) and macrovascular human umbilical vein endothelial cells (HUVE). Methods. Cultured endothelial cells were treated for 4 hours with medium alone or tumor necrosis factor α (TNF α). The expression of endothelial adhesion molecules was evaluated by flow cytometry, cell enzyme-linked immunosorbent assay, and Northern blot analysis. Results. SMEC continuously expressed E-selectin under basal culture conditions, whereas FSE and HUVE did not. TNF α treatment of rheumatoid arthritis (RA) SMEC resulted in sustained peak expression of E-selectin for up to 24 hours, which subsequently declined but remained elevated even at 72 hours. In contrast, peak E-selectin expression in FSE and HUVE occurred between 4 hours and 16 hours after TNF α treatment and then declined to near basal levels by 24–48 hours. SMEC expressed significantly higher levels of ICAM-1 compared with HUVE under basal culture conditions. There was no difference between SMEC, FSE, and HUVE in the expression of P-selectin, VCAM-1, ICAM-2, or PECAM-1. Northern blot analysis demonstrated that the levels of E-selectin expression by TNF α-stimulated endothelial cells correlated with their respective messenger RNA levels. Conclusion. Regulation of E-selectin and ICAM-1 expression in RA synovial endothelium is different from that in neonatal foreskin and human umbilical vein endothelium. The augmented expression of adhesion molecules in RA synovial endothelium may facilitate the recruitment of leukocytes to this site. 相似文献
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Orla McBride Sarah Butter Jamie Murphy Mark Shevlin Todd K. Hartman Kate M. Bennett Thomas V. A. Stocks Alex Lloyd Ryan McKay Jilly GibsonMiller Liat Levita Liam Mason Anton P. Martinez Philip Hyland Frdrique Vallires Thanos Karatzias Carmen Valiente Carmelo Vazquez Richard P. Bentall 《International journal of methods in psychiatric research》2022,31(1)
ObjectivesThis paper outlines fieldwork procedures for Wave 4 of the COVID‐19 Psychological Research Consortium (C19PRC) Study in the UK during November–December 2020.MethodsRespondents provided data on socio‐political attitudes, beliefs, and behaviours, and mental health disorders (anxiety, depression, and posttraumatic stress). In Phase 1, adults (N = 2878) were reinvited to participate. At Phase 2, new recruitment: (i) replenished the longitudinal strand to account for attrition; and (ii) oversampled from the devolved UK nations to facilitate robust between‐country analyses for core study outcomes. Weights were calculated using a survey raking algorithm to ensure the longitudinal panel was representative of the baseline sample characteristics.ResultsIn Phase 1, 1796 adults were successfully recontacted and provided full interviews at Wave 4 (62.4% retention rate). In Phase 2, 292 new respondents were recruited to replenish the panel, as well as 1779 adults from Wales, Scotland, and Northern Ireland, who were representative of the socio‐political composition of the adult populations in these nations. The raking procedure successfully re‐balanced the longitudinal panel to within 1% of population estimates for selected socio‐demographic characteristics.ConclusionThe C19PRC Study offers a unique opportunity to facilitate and stimulate interdisciplinary research addressing important public health questions relating to the COVID‐19 pandemic. 相似文献
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Background. A common sense view in psychotherapy holds that there are individual differences in response to different treatments. However, despite considerable effort, no clear rationale exists to guide the selection of therapy for individual patients. Objectives. Rather than focusing on specific components of therapy as a basis to predict interactions between patients and treatments, we draw on motivational concordance theory and a contextual model of psychotherapy to test whether, in an analogue study, perceived effectiveness of different therapy vignettes is related to human values. Method. Two samples (undergraduates and members of the public) read short vignettes, informed by six therapies for depression (cognitive behaviour therapy, client‐centred therapy, antidepressant medication, existential psychotherapy, psychodynamic psychotherapy, and a complementary medicine: Bach flower essences), provided ratings of perceived effectiveness, and completed questionnaire measures of dispositional motivations (Schwartz Values Scale and the Spiritual Connection Questionnaire‐14). Responses were analysed using multidimensional scaling (MDS). Results. In both samples, expectancy for the cognitive behavioural‐informed vignette was related to Self‐direction and Stimulation, and was opposed to Tradition, Conformity and Security. Expectancies for the Drug vignette were associated with Power and Security. Conclusion. People perceive therapies as more effective if the therapy is congruent with their values. These preliminary data suggest motivational concordance is a useful framework for predicting client‐treatment interactions. 相似文献
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