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111.
Freedman VA Aykan H Wolf DA Marcotte JE 《The journals of gerontology. Series B, Psychological sciences and social sciences》2004,59(1):S25-S33
OBJECTIVES: We describe how paid and unpaid home care hours received by older unmarried Americans change in response to disability dynamics. We test whether responses to disability declines and improvements are symmetric; that is, we test whether reductions in care hours that are due to disability improvements are of similar magnitude to increases in care hours that are due to disability declines. METHODS: Using a national sample of older unmarried Americans, we examine changes in total hours, paid hours, and unpaid hours of care in response to declines and improvements in personal care (activities of daily living, or ADLs) and routine care (instrumental ADLs, or IADLs) disability. We model changes in the total hours of care received in the past month and jointly model changes in unpaid and paid hours, using Tobit models. RESULTS: Changes in the total hours of care received respond to both increases and decreases in the count of ADL limitations and appear close to symmetric. In contrast, responses to IADL disability dynamics appear to be far less symmetric: Although increases in the count of IADL limitations are met with substantial increases in the total hours of care, decreases are not met with correspondingly large declines in care. The same general pattern is found for unpaid and paid care, and for Medicaid-funded home care. DISCUSSION: Disability and care are not static constructs in old age. Older unmarried persons experience worsening, stabilizing, and recovery of function, and their care hours change accordingly. Evaluations of home care programs must be cognizant of such dynamic realities. 相似文献
112.
Emily K. Plowman Stephanie A. Watts Raele Robison Lauren Tabor Charles Dion Joy Gaziano Tuan Vu Clifton Gooch 《Dysphagia》2016,31(3):383-390
Dysphagia and aspiration are prevalent in amyotrophic lateral sclerosis (ALS) and contribute to malnutrition, aspiration pneumonia, and death. Early detection of at risk individuals is critical to ensure maintenance of safe oral intake and optimal pulmonary function. We therefore aimed to determine the discriminant ability of voluntary cough airflow measures in detecting penetration/aspiration status in ALS patients. Seventy individuals with ALS (El-Escorial criteria) completed voluntary cough spirometry testing and underwent a standardized videofluoroscopic swallowing evaluation (VFSE). A rater blinded to aspiration status derived six objective measures of voluntary cough airflow and evaluated airway safety using the penetration–aspiration scale (PAS). A between groups ANOVA (safe vs. unsafe swallowers) was conducted and sensitivity, specificity, area under the curve (AUC) and likelihood ratios were calculated. VFSE analysis revealed 24 penetrator/aspirators (PAS ≥3) and 46 non-penetrator/aspirators (PAS ≤2). Cough volume acceleration (CVA), peak expiratory flow rise time (PEFRT), and peak expiratory flow rate (PEFR) were significantly different between airway safety groups (p < 0.05) and demonstrated significant discriminant ability to detect the presence of penetration/aspiration with AUC values of: 0.85, 0.81, and 0.78, respectively. CVA <45.28 L/s/s, PEFR <3.97 L/s, and PEFRT >76 ms had sensitivities of 91.3, 82.6, and 73.9 %, respectively, and specificities of 82.2, 73.9, and 78.3 % for identifying ALS penetrator/aspirators. Voluntary cough airflow measures identified ALS patients at risk for penetration/aspiration and may be a valuable screening tool with high clinical utility. 相似文献
113.
Konstantinos Toutouzas Georgios Benetos Vasilis Voudris Maria Drakopoulou Konstantinos Stathogiannis George Latsios Andreas Synetos Alexios Antonopoulos Elias Kosmas Ioannis Iakovou Georgios Katsimagklis Antonios Mastrokostopoulos Sotiris Moraitis Vicki Zeniou Haim Danenberg Manolis Vavuranakis Dimitris Tousoulis 《JACC: Cardiovascular Interventions》2019,12(8):767-777
Objectives
The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial.Background
There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV.Methods
Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach.Results
A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: ?8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths.Conclusions
Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927) 相似文献114.
115.
Christian M. Girgis Roderick J. Clifton‐Bligh Nigel Turner Sue Lynn Lau Jenny E. Gunton 《Clinical endocrinology》2014,80(2):169-181
Accompanying the high rates of vitamin D deficiency observed in many countries, there is increasing interest in the physiological functions of vitamin D. Vitamin D is recognized to exert extra‐skeletal actions in addition to its classic roles in bone and mineral homeostasis. Here, we review the evidence for vitamin D's actions in muscle on the basis of observational studies, clinical trials and basic research. Numerous observational studies link vitamin D deficiency with muscle weakness and sarcopaenia. Randomized trials predominantly support an effect of vitamin D supplementation and the prevention of falls in older or institutionalized patients. Studies have also examined the effect of vitamin D in athletic performance, both inferentially by UV radiation and directly by vitamin D supplementation. Effects of vitamin D in muscle metabolic function, specifically insulin sensitivity, are also addressed in this review. At a mechanistic level, animal studies have evaluated the roles of vitamin D and associated minerals, calcium and phosphate, in muscle function. In vitro studies have identified molecular pathways by which vitamin D regulates muscle cell signalling and gene expression. This review evaluates evidence for the various roles of vitamin D in skeletal muscle and discusses controversies that have made this a dynamic field of research. 相似文献
116.
Aaron J. Gassmann Jennifer L. Petzold-Maxwell Eric H. Clifton Mike W. Dunbar Amanda M. Hoffmann David A. Ingber Ryan S. Keweshan 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(14):5141-5146
The widespread planting of crops genetically engineered to produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) places intense selective pressure on pest populations to evolve resistance. Western corn rootworm is a key pest of maize, and in continuous maize fields it is often managed through planting of Bt maize. During 2009 and 2010, fields were identified in Iowa in which western corn rootworm imposed severe injury to maize producing Bt toxin Cry3Bb1. Subsequent bioassays revealed Cry3Bb1 resistance in these populations. Here, we report that, during 2011, injury to Bt maize in the field expanded to include mCry3A maize in addition to Cry3Bb1 maize and that laboratory analysis of western corn rootworm from these fields found resistance to Cry3Bb1 and mCry3A and cross-resistance between these toxins. Resistance to Bt maize has persisted in Iowa, with both the number of Bt fields identified with severe root injury and the ability western corn rootworm populations to survive on Cry3Bb1 maize increasing between 2009 and 2011. Additionally, Bt maize targeting western corn rootworm does not produce a high dose of Bt toxin, and the magnitude of resistance associated with feeding injury was less than that seen in a high-dose Bt crop. These first cases of resistance by western corn rootworm highlight the vulnerability of Bt maize to further evolution of resistance from this pest and, more broadly, point to the potential of insects to develop resistance rapidly when Bt crops do not achieve a high dose of Bt toxin.The global area devoted to transgenic crops producing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) has increased rapidly over the past 15 y, with Bt crops covering more than 69 million hectares in 2012 (1). Most of this area was planted in Bt cotton and Bt maize (1). Benefits of Bt crops include effective management of target pests, decreased use of conventional insecticides, and reduced harm to nontarget organisms (2–5). However, the evolution of resistance could diminish these benefits. The western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is a major pest of maize, with larval feeding on maize roots and associated management costs causing economic losses in excess of $1 billion per year (6). Through 2013, three Bt toxins have been used in transgenic maize for management of western corn rootworm: Cry3Bb1, mCry3A, and Cry34/35Ab1 (7).In the United States and elsewhere, commercial registration of a Bt crop is accompanied by a resistance-management plan to delay the onset of pest resistance. Resistance management for Bt crops has focused on the refuge strategy, in which refuges of non-Bt crops allow the survival of Bt-susceptible insects, which may mate with resistant insects that survive on the Bt crop (8). To the extent that the heterozygous progeny from these matings have lower fitness on a Bt crop than their Bt-resistant parent, delays in resistance may be achieved, and these delays in resistance increase with the quantity of refuge (9). Additionally, refuges are far more effective in delaying resistance when Bt crops achieve a high dose of toxin against a target pest. High-dose Bt crops kill more than 99.99% of susceptible insects and render resistance a functionally recessive trait (9, 10). None of the currently commercialized Bt maize targeting the western corn rootworm is high dose, so the risk of resistance is increased (11, 12).In 2003, Cry3Bb1 maize was registered by the United States Environmental Protection Agency (US EPA) for management of western corn rootworm larvae (7). In 2009, farmers in Iowa observed severe injury to Cry3Bb1 maize by larval western corn rootworm in the field, and subsequent laboratory assays revealed that this injury was associated with Cry3Bb1 resistance (13). More fields with Cry3Bb1 resistance were identified in 2010 (14), and research in fields identified in 2009 as harboring Cry3Bb1-resistant western corn rootworm found no difference in survival for this pest between non-Bt maize and Cry3Bb1 maize (11). Current threats to Bt maize include the spread of Bt-resistant western corn rootworm and the loss of additional Bt toxins through the presence of cross-resistance. In this paper we report that injury to Cry3Bb1 maize in the field has persisted through 2011 and expanded to include mCry3A maize. Analysis of western corn rootworm collected in 2011 revealed that (i) severe injury to Cry3Bb1 maize and mCry3A maize in the field was associated with resistance, and (ii) cross-resistance between Cry3Bb1 and mCry3A was present. These results demonstrate that insects can evolve resistance rapidly to Bt crops that are not high dose and raise concerns about the adequacy of current resistance-management strategies. 相似文献
117.
Kerry Hall Stacey Vervoort Letitia Del Fabbro Fiona Rowe Minniss Vicki Saunders Karen Martin Andrea Bialocerkowski Eleanor Milligan Melanie Syron Roianne West 《Nursing inquiry》2023,30(1):e12524
There is an inextricable link between cultural and clinical safety. In Australia high-profile Aboriginal deaths in custody, publicised institutional racism in health services and the international Black Lives Matter movement have cemented momentum to ensure culturally safe care. However, racism within health professionals and health professional students remains a barrier to increasing the number of Aboriginal and Torres Strait Islander Health professionals. The Australian Health Practitioner Regulation Agency's Aboriginal and Torres Strait Islander Health Strategy's objective to ‘eliminate racism from the health system’, and the recent adoption of the Aboriginal and Torres Strait Islander peoples led cultural safety definition, has instigated systems level reflections on decolonising practice. This article explores cultural safety as the conceptual antithesis to racism, examining its origins, and contemporary evolution led by Aboriginal and Torres Strait Islander peoples in Australia, including its development in curriculum innovation. The application of cultural safety is explored using in-depth reflection, and the crucial development of integrating critical consciousness theory, as a precursor to culturally safe practice, is discussed. Novel approaches to university curriculum development are needed to facilitate culturally safe and decolonised learning and working environments, including the key considerations of non-Indigenous allyship and collaborative curriculum innovations and initiatives. 相似文献
118.
Zuzana Magdolenova Andrew Collins Ashutosh Kumar Alok Dhawan Vicki Stone 《Nanotoxicology》2014,8(3):233-278
Engineered nanoparticles (NPs) are widely used in different technologies but their unique properties might also cause adverse health effects. In reviewing recent in vitro and in vivo genotoxicity studies we discuss potential mechanisms of genotoxicity induced by NPs. Various factors that may influence genotoxic response, including physico-chemical properties and experimental conditions, are highlighted. From 4346 articles on NP toxicity, 112 describe genotoxicity studies (94 in vitro, 22 in vivo). The most used assays are the comet assay (58 in vitro, 9 in vivo), the micronucleus assay (31 in vitro, 14 in vivo), the chromosome aberrations test (10 in vitro, 1 in vivo) and the bacterial reverse mutation assay (13 studies). We describe advantages and potential problems with different methods and suggest the need for appropriate methodologies to be used for investigation of genotoxic effects of NPs, in vitro and in vivo. 相似文献
119.
120.
The transfer from pediatric to adult diabetes health care for emerging adults with type 1 diabetes (T1D) has received increasing attention in the literature. This review analyzes the effect of this health care transfer on the outcomes of diabetes care visit attendance, glycemic control, and acute diabetes‐related complications, and assesses the methodological strength of the studies reporting observational and interventional data. Observational studies, often limited by incomplete data, report a decline in diabetes care visits but an improvement or no change in hemoglobin A1c (HbA1c) after transfer to adult care. Results from studies reporting a transition intervention are restricted by lack of appropriate control groups and the collection of data both before and after transfer of care. Very few methodologically strong studies are available to guide clinicians with the transition from pediatric to adult care, and these shortcomings should be addressed in future studies designed to facilitate and improve the care of emerging adults with T1D. 相似文献