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51.
Tara?Clinton-McHarg Sze?Lin?Yoong Flora?Tzelepis Tim?Regan Alison?Fielding Eliza?Skelton Melanie?Kingsland Jia?Ying?Ooi Luke?WolfendenEmail author 《Implementation science : IS》2015,11(1):148
Background
Recent reviews have synthesised the psychometric properties of measures developed to examine implementation science constructs in healthcare and mental health settings. However, no reviews have focussed primarily on the properties of measures developed to assess innovations in public health and community settings. This review identified quantitative measures developed in public health and community settings, examined their psychometric properties, and described how the domains of each measure align with the five domains and 37 constructs of the Consolidated Framework for Implementation Research (CFIR).Methods
MEDLINE, PsycINFO, EMBASE, and CINAHL were searched to identify publications describing the development of measures to assess implementation science constructs in public health and community settings. The psychometric properties of each measure were assessed against recommended criteria for validity (face/content, construct, criterion), reliability (internal consistency, test-retest), responsiveness, acceptability, feasibility, and revalidation and cross-cultural adaptation. Relevant domains were mapped against implementation constructs defined by the CFIR.Results
Fifty-one measures met the inclusion criteria. The majority of these were developed in schools, universities, or colleges and other workplaces or organisations. Overall, most measures did not adequately assess or report psychometric properties. Forty-six percent of measures using exploratory factor analysis reported >50 % of variance was explained by the final model; none of the measures assessed using confirmatory factor analysis reported root mean square error of approximation (<0.06) or comparative fit index (>0.95). Fifty percent of measures reported Cronbach’s alpha of <0.70 for at least one domain; 6 % adequately assessed test-retest reliability; 16 % of measures adequately assessed criterion validity (i.e. known-groups); 2 % adequately assessed convergent validity (r?>?0.40). Twenty-five percent of measures reported revalidation or cross-cultural validation. The CFIR constructs most frequently assessed by the included measures were relative advantage, available resources, knowledge and beliefs, complexity, implementation climate, and other personal resources (assessed by more than ten measures). Five CFIR constructs were not addressed by any measure.Conclusions
This review highlights gaps in the range of implementation constructs that are assessed by existing measures developed for use in public health and community settings. Moreover, measures with robust psychometric properties are lacking. Without rigorous tools, the factors associated with the successful implementation of innovations in these settings will remain unknown52.
Anne-Gaelle Besnard Rodrigo Guabiraba Wanda Niedbala Jennifer Palomo Flora Reverchon Tovah N. Shaw Kevin N. Couper Bernhard Ryffel Foo Y. Liew 《PLoS pathogens》2015,11(2)
Cerebral malaria (CM) is a complex parasitic disease caused by Plasmodium sp. Failure to establish an appropriate balance between pro- and anti-inflammatory immune responses is believed to contribute to the development of cerebral pathology. Using the blood-stage PbA (Plasmodium berghei ANKA) model of infection, we show here that administration of the pro-Th2 cytokine, IL-33, prevents the development of experimental cerebral malaria (ECM) in C57BL/6 mice and reduces the production of inflammatory mediators IFN-γ, IL-12 and TNF-α. IL-33 drives the expansion of type-2 innate lymphoid cells (ILC2) that produce Type-2 cytokines (IL-4, IL-5 and IL-13), leading to the polarization of the anti-inflammatory M2 macrophages, which in turn expand Foxp3 regulatory T cells (Tregs). PbA-infected mice adoptively transferred with ILC2 have elevated frequency of M2 and Tregs and are protected from ECM. Importantly, IL-33-treated mice deleted of Tregs (DEREG mice) are no longer able to resist ECM. Our data therefore provide evidence that IL-33 can prevent the development of ECM by orchestrating a protective immune response via ILC2, M2 macrophages and Tregs. 相似文献
53.
Martin L. Decaris Claire L. Emson Kelvin Li Michelle Gatmaitan Flora Luo Jerome Cattin Corelle Nakamura William E. Holmes Thomas E. Angel Marion G. Peters Scott M. Turner Marc K. Hellerstein 《PloS one》2015,10(4)
Accumulation and degradation of scar tissue in fibrotic liver disease occur slowly, typically over many years. Direct measurement of fibrogenesis, the rate of scar tissue deposition, may provide valuable therapeutic and prognostic information. We describe here results from a pilot study utilizing in vivo metabolic labeling to measure the turnover rate of hepatic collagen and collagen-associated proteins in plasma for the first time in human subjects. Eight subjects with chronic liver disease were labeled with daily oral doses of 2H2O for up to 8 weeks prior to diagnostic liver biopsy and plasma collection. Tandem mass spectrometry was used to measure the abundance and fractional synthesis rate (FSR) of proteins in liver and blood. Relative protein abundance and FSR data in liver revealed marked differences among subjects. FSRs of hepatic type I and III collagen ranged from 0.2–0.6% per day (half-lives of 4 months to a year) and correlated significantly with worsening histologic fibrosis. Analysis of plasma protein turnover revealed two collagen-associated proteins, lumican and transforming growth factor beta-induced-protein (TGFBI), exhibiting FSRs that correlated significantly with FSRs of hepatic collagen. In summary, this is the first direct measurement of liver collagen turnover in vivo in humans and suggests a high rate of collagen remodeling in advanced fibrosis. In addition, the FSRs of collagen-associated proteins in plasma are measurable and may provide a novel strategy for monitoring hepatic fibrogenesis rates. 相似文献
54.
A new opportunistic annelid (Ophryotrocha cyclops) discovered on benthic substrates underneath finfish aquaculture sites in Newfoundland (NL) may be involved in the remediation of organic wastes. At those aquaculture sites, bacterial mats and O. cyclops often coexist and are used as indicators of organic enrichment. Little is known on the trophic strategies used by these annelids, including whether they might consume bacteria or other aquaculture-derived wastes. We studied the lipid and fatty acid composition of the annelids and their potential food sources (degraded flocculent organic matter, fresh fish pellets and bacterial mats) to investigate feeding relationships in these habitats and compared the lipid and fatty acid composition of annelids before and after starvation. Fish pellets were rich in lipids, mainly terrestrially derived C18 fatty acids (18:1ω9, 18:2ω6, 18:3ω3), while bacterial samples were mainly composed of ω7 fatty acids, and flocculent matter appeared to be a mixture of fresh and degrading fish pellets, feces and bacteria. Ophryotrocha cyclops did not appear to store excessive amounts of lipids (13%) but showed a high concentration of ω3 and ω6 fatty acids, as well as a high proportion of the main fatty acids contained in fresh fish pellets and bacterial mats. The dorvilleids and all potential food sources differed significantly in their lipid and fatty acid composition. Interestingly, while all food sources contained low proportions of 20:5ω3 and 20:2ω6, the annelids showed high concentrations of these two fatty acids, along with 20:4ω6. A starvation period of 13 days did not result in a major decrease in total lipid content; however, microscopic observations revealed that very few visible lipid droplets remained in the gut epithelium after three months of starvation. Ophryotrocha cyclops appears well adapted to extreme environments and may rely on lipid-rich organic matter for survival and dispersal in cold environments. 相似文献
55.
Stefano Lancellotti Vincenzo De Filippis Nicola Pozzi Flora Peyvandi Roberta Palla Bianca Rocca Sergio Rutella Dario Pitocco Pier Mannuccio Mannucci Raimondo De Cristofaro 《Free radical biology & medicine》2010,48(3):446-456
An enhanced formation of reactive oxygen species and peroxynitrite occurs in several clinical settings including diabetes, coronary artery disease, stroke, sepsis, and chronic inflammatory diseases. Peroxynitrite oxidizes methionine and tyrosine residues to methionine sulfoxide (MetSO) and 3-nitrotyrosine (NT), respectively. Notably, ADAMTS-13 cleaves von Willebrand factor (VWF) exclusively at the Tyr1605–Met1606 peptide bond in the A2 domain. We hypothesized that peroxynitrite could oxidize either or both of these amino acid residues, thus potentially affecting ADAMTS-13-mediated cleavage. We tested our hypothesis using synthetic peptide substrates based on: (1) VWF Asp1596–Ala1669 sequence (VWF74) and (2) VWF Asp1596–Ala1669 sequence containing nitrotyrosine (VWF74-NT) or methionine sulfoxide (VWF74-MetSO) at position 1605 or 1606, respectively. The peptides were treated with recombinant ADAMTS-13 and the cleavage products analyzed by RP-HPLC. VWF74 oxidized by peroxynitrite underwent a severe impairment of its hydrolysis. Likewise, VWF74-MetSO was minimally hydrolyzed, whereas VWF74-NT was hydrolyzed slightly more efficiently than VWF74. Oxidation by peroxynitrite of purified VWF multimers inhibited ADAMTS-13 hydrolysis, but did not alter their electrophoretic pattern nor their ability to induce platelet agglutination by ristocetin. Moreover, VWF purified from type 2 diabetic patients showed oxidative damage, as revealed by enhanced carbonyl, NT, and MetSO content and was partially resistant to ADAMTS-13 hydrolysis. In conclusion, peroxynitrite may contribute to prothrombotic effects, hindering the proteolytic processing by ADAMTS-13 of high-molecular-weight VWF multimers, which have the highest ability to bind and activate platelets in the microcirculation. 相似文献
56.
Background
Colorectal cancer (CRC) fulfills the World Health Organization criteria for mass screening, but screening uptake is low in most countries. CRC screening is resource intensive, and it is unclear if an optimal strategy exists. The objective of this study was to perform an economic evaluation of CRC screening in average risk North American individuals considering all relevant screening modalities and current CRC treatment costs.Methods and Findings
An incremental cost-utility analysis using a Markov model was performed comparing guaiac-based fecal occult blood test (FOBT) or fecal immunochemical test (FIT) annually, fecal DNA every 3 years, flexible sigmoidoscopy or computed tomographic colonography every 5 years, and colonoscopy every 10 years. All strategies were also compared to a no screening natural history arm. Given that different FIT assays and collection methods have been previously tested, three distinct FIT testing strategies were considered, on the basis of studies that have reported “low,” “mid,” and “high” test performance characteristics for detecting adenomas and CRC. Adenoma and CRC prevalence rates were based on a recent systematic review whereas screening adherence, test performance, and CRC treatment costs were based on publicly available data. The outcome measures included lifetime costs, number of cancers, cancer-related deaths, quality-adjusted life-years gained, and incremental cost-utility ratios. Sensitivity and scenario analyses were performed. Annual FIT, assuming mid-range testing characteristics, was more effective and less costly compared to all strategies (including no screening) except FIT-high. Among the lifetimes of 100,000 average-risk patients, the number of cancers could be reduced from 4,857 to 1,782 and the number of CRC deaths from 1,393 to 457, while saving CAN$68 per person. Although screening patients with FIT became more expensive than a strategy of no screening when the test performance of FIT was reduced, or the cost of managing CRC was lowered (e.g., for jurisdictions that do not fund expensive biologic chemotherapeutic regimens), CRC screening with FIT remained economically attractive.Conclusions
CRC screening with FIT reduces the risk of CRC and CRC-related deaths, and lowers health care costs in comparison to no screening and to other existing screening strategies. Health policy decision makers should consider prioritizing funding for CRC screening using FIT. Please see later in the article for the Editors'' Summary 相似文献57.
Serlin Bruce S.; Lew Roger R.; Krasnoshtein Flora; Krol Justyna; Sumida Kevin D. 《Plant & cell physiology》1996,37(2):175-179
Red light mediates chloroplast movement and increased activityof calcium-activated potassium channels on the plasma membraneof the alga Mougeotia sp. (UTEX LB 734). When activation ismediated by phytochrome, a far-red light irradiation given sometime after the red light irradiation will reverse the effectof the red light, due to phytochrome photoreversibility. Wecharacterized the escape times (time required for loss of photoreversibility)for these two processes to compare the transduction pathwaysinvolved in chloroplast rotation and channel activation. Theescape time for chloroplast rotation was 2.5 min after red lightirradiation (red and far-red light irradiations were 30 s).For channel activation, shorter red and far-red light irradiations(10 s) had to be used to obtain an escape time of 20 s. Thedifference in the escape times suggests that there is relativelyrapid divergence in the transduction pathways leading from phytochromeactivation (only one molecular species of phytochrome is foundin Mougeotia) to each of the two responses in the same cellularsystem. Because channel activation occurs 24 min afterirradiation while the escape time is 20 s, it is unlikely thatphytochrome acts directly on the channel. (Received September 26, 1995; Accepted December 28, 1995) 相似文献
58.
Rodent species abundance and diversity in Western Serengeti are evaluated and discussed in relation to different levels of conservation status [Unprotected Area (UA), Game Reserve (GR) and National Park (NP)] and broad site differences in human livelihood activities. A total of 2170 individuals, spread over 16 rodent species, were caught in a capture‐mark‐recapture study which covered both the dry and wet seasons. The more humid site (Tabora B) in the northern part of Serengeti had the highest diversity of rodents followed by the Mihale site at the western extension. The driest site at Robanda had the lowest overall species diversity. Diversity also varied between the three levels of conservation status whereby the UA had the least diversity while the NP, which enjoyed the highest level of conservation status, had the highest diversity of rodents. Unprotected Area and NP plots at Tabora B showed a rodent species similarity index of 40%; all the other paired plots scored over 50% similarity indices, suggesting that, within a site, species composition did not vary significantly between the three levels of conservation status. The Robanda site had the highest (56%) overall abundance of rodents; Mihale and Tabora B sites had about the same level of rodent abundance (20 and 24% respectively). For the Mihale site, Mastomys natalensis ranked first followed by Arvicanthis niloticus and Tatera robusta, each of which contained 40, 38 and 16%, respectively, of all individuals caught at the site. For the Robanda site, the figures were 66%A. niloticus, 22%M. natalensis and 9%T. robusta; while for the Tabora B site the scores were 37%M. natalensis, 18%T. robusta and 11%Lemniscomys barbarus. The differences in diversity, species composition and population abundance appear to result largely from physiognomic vegetation types, and habitat perturbations caused by livelihood activities in Western Serengeti. 相似文献
59.
Potenza MA Marasciulo FL Tarquinio M Tiravanti E Colantuono G Federici A Kim JA Quon MJ Montagnani M 《American journal of physiology. Endocrinology and metabolism》2007,292(5):E1378-E1387
Epigallocatechin gallate (EGCG), a bioactive polyphenol in green tea, may augment metabolic and vascular actions of insulin. Therefore, we investigated effects of EGCG treatment to simultaneously improve cardiovascular and metabolic function in spontaneously hypertensive rats (SHR; model of metabolic syndrome with hypertension, insulin resistance, and overweight). In acute studies, EGCG (1-100 microM) elicited dose-dependent vasodilation in mesenteric vascular beds (MVB) isolated from SHR ex vivo that was inhibitable by N(omega)-nitro-L-arginine methyl ester (L-NAME; nitric oxide synthase antagonist) or wortmannin [phosphatidylinositol (PI) 3-kinase inhibitor]. In chronic studies, 9-wk-old SHR were treated by gavage for 3 wk with EGCG (200 mg.kg(-1).day(-1)), enalapril (30 mg.kg(-1).day(-1)), or vehicle. A separate group of SHR receiving L-NAME (80 mg/l in drinking water) was treated for 3 wk with either EGCG or vehicle. Vasodilator actions of insulin were significantly improved in MVB from EGCG- or enalapril-treated SHR (when compared with vehicle-treated SHR). Both EGCG and enalapril therapy significantly lowered systolic blood pressure (SBP) in SHR. EGCG therapy of SHR significantly reduced infarct size and improved cardiac function in Langendorff-perfused hearts exposed to ischemia-reperfusion (I/R) injury. In SHR given L-NAME, beneficial effects of EGCG on SBP and I/R were not observed. Both enalapril and EGCG treatment of SHR improved insulin sensitivity and raised plasma adiponectin levels. We conclude that acute actions of EGCG to stimulate production of nitric oxide from endothelium using PI 3-kinase-dependent pathways may explain, in part, beneficial effects of EGCG therapy to simultaneously improve metabolic and cardiovascular pathophysiology in SHR. These findings may be relevant to understanding potential benefits of green tea consumption in patients with the metabolic syndrome. 相似文献
60.
Metabotropic glutamate receptor type 5 (mGluR5) modulates dopamine and glutamate neurotransmission at central synapses. In this study, we addressed the role of mGluR5 in l-DOPA-induced dyskinesia, a movement disorder that is due to abnormal activation of both dopamine and glutamate receptors in the basal ganglia. A selective and potent mGluR5 antagonist, 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl] pyridine, was tested for its ability to modulate molecular, behavioural and neurochemical correlates of dyskinesia in 6-hydroxydopamine-lesioned rats treated with l-DOPA. The compound significantly attenuated the induction of abnormal involuntary movements (AIMs) by chronic l-DOPA treatment at doses that did not interfere with the rat physiological motor activities. These effects were paralleled by an attenuation of molecular changes that are strongly associated with the dyskinesiogenic action of l-DOPA (i.e. up-regulation of prodynorphin mRNA in striatal neurons). Using in vivo microdialysis, we found a temporal correlation between the expression of l-DOPA-induced AIMs and an increased GABA outflow within the substantia nigra pars reticulata. When co-administered with l-DOPA, 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl] pyridine greatly attenuated both the increase in nigral GABA levels and the expression of AIMs. These data demonstrate that mGluR5 antagonism produces strong anti-dyskinetic effects in an animal model of Parkinson's disease through central inhibition of the molecular and neurochemical underpinnings of l-DOPA-induced dyskinesia. 相似文献