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991.
A major question in neuroscience concerns how widely separated brain regions coordinate their activity to produce unitary cognitive states or motor actions. To investigate this question, we employed multisite, multielectrode recording in rats to study how olfactory and motor circuits are coupled prior to the execution of an olfactory-driven, GO/NO-GO variant of a skilled, rapidly executed (∼350–600 ms) reaching task. During task performance, we recorded multi-single units and local field potentials (LFPs) simultaneously from the rats’ olfactory cortex (specifically, the posterior piriform cortex) and from cortical and subcortical motor sites (the caudal forepaw M1, and the magnocellular red nucleus, respectively). Analyses on multi-single units across areas revealed an increase in beta-frequency spiking (12–30 Hz) during a ∼100 ms window surrounding the Final Sniff of the GO cue before lifting the arm (the “Sniff-GO window”) that was seldom seen when animals sniffed the NO-GO cue. Also during the Sniff-GO window, LFPs displayed a striking increase in beta, low-gamma, and high-gamma energy (12–30, 30–50, and 50–100 Hz, respectively), and oscillations in the high gamma band appeared to be coherent across the recorded sites. These results indicate that transient, multispectral coherence across cortical and subcortical brain sites is part of the coordination process prior to sensory-guided movement initiation. Raymond Hermer-Vazquez, Linda Hermer-Vazquez these two authors contributed equally.  相似文献   
992.
With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent years. Nanomaterials themselves can be used as image agents or therapeutic drugs, and for drug and gene delivery, biological devices, nanoelectronic biosensors or molecular nanotechnology. As the composition, morphology, chemical properties, implant sites as well as potential applications become more and more complex, human biosafety of nanomaterials for clinical use has become a major concern. If nanoparticles accumulate in the human body or interact with the body molecules or chemical components, health risks may also occur. Accordingly, the unique chemical and physical properties, potential applications in medical fields, as well as human biosafety in clinical trials are reviewed in this study. Finally, this article tries to give some suggestions for future work in nanomedicine research. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
993.
The recent emergence of colistin (COL) resistance, particularly mcr-1 plasmid-mediated COL resistance in Gram-negative bacteria, has led to renewed interest in antibiotic combinations to overcome clinical therapeutic impasses. The aim of this study was to evaluate the potential of the synergistic and bactericidal activity of COL in combination with sulphonamide compounds, including sulfadiazine (SDI), sulfamethoxazole (SMX) and trimethoprim/sulfamethoxazole (SXT), as well as trimethoprim (TMP) against clinical COL-resistant bacterial strains, including strains with the plasmid-encoded mcr-1 gene. A collection of 55 COL-resistant and -susceptible strains from different origins (Laos, Thailand and France) was used in this study. Several in vitro methods were used to determine the potential of the synergistic activity of these combinations, including Etest on agar pre-treated plates, the Etest cross method and the chequerboard assay. A time–kill assay was performed to evaluate the potential bactericidal activity of combinations in addition to synergistic activity. Significant synergistic activity was observed with all combinations tested. The combination of COL?+?SDI presented the highest synergistic effect against the various species of COL-resistant strains (92.7%). For the other combinations, a synergistic effect was also observed but with lower frequency for COL?+?SMX (33.3%), COL?+?TMP (47.3%) and COL?+?SXT (31.5%). Synergy was observed independently of the COL resistance mechanism. These in vitro results suggest that the combination of COL?+?SDI would appear to be justifiable in patients with multidrug-resistant bacterial infections that cannot be treated with COL monotherapy.  相似文献   
994.

Background

Online resources are a source of information for parents of premature babies when their baby is discharged from hospital.

Objectives

To explore what topics parents deemed important after returning home from hospital with their premature baby and to evaluate the quality of existing websites that provide information for parents post‐discharge.

Methods

In stage 1, 23 parents living in Northern Ireland participated in three focus groups and shared their information and support needs following the discharge of their infant(s). In stage 2, a World Wide Web (WWW) search was conducted using Google, Yahoo and Bing search engines. Websites meeting pre‐specified inclusion criteria were reviewed using two website assessment tools and by calculating a readability score. Website content was compared to the topics identified by parents in the focus groups.

Results

Five overarching topics were identified across the three focus groups: life at home after neonatal care, taking care of our family, taking care of our premature baby, baby's growth and development and help with getting support and advice. Twenty‐nine sites were identified that met the systematic web search inclusion criteria. Fifteen (52%) covered all five topics identified by parents to some extent and 9 (31%) provided current, accurate and relevant information based on the assessment criteria.

Conclusion

Parents reported the need for information and support post‐discharge from hospital. This was not always available to them, and relevant online resources were of varying quality. Listening to parents needs and preferences can facilitate the development of high‐quality, evidence‐based, parent‐centred resources.  相似文献   
995.
Assessment of clinical competence is complex and inference based. Trustworthy and defensible assessment processes must have favourable evidence of validity, particularly where decisions are considered high stakes. We aimed to organize, collect and interpret validity evidence for a high stakes simulation based assessment strategy for certifying paramedics, using Kane’s validity framework, which some report as challenging to implement. We describe our experience using the framework, identifying challenges, decisions points, interpretations and lessons learned. We considered data related to four inferences (scoring, generalization, extrapolation, implications) occurring during assessment and treated validity as a series of assumptions we must evaluate, resulting in several hypotheses and proposed analyses. We then interpreted our findings across the four inferences, judging if the evidence supported or refuted our proposed uses of the assessment data. Data evaluating “Scoring” included: (a) desirable tool characteristics, with acceptable inter-item correlations (b) strong item-total correlations (c) low error variance for items and raters, and (d) strong inter-rater reliability. Data evaluating “Generalizability” included: (a) a robust sampling strategy capturing the majority of relevant medical directives, skills and national competencies, and good overall and inter-station reliability. Data evaluating “Extrapolation” included: low correlations between assessment scores by dimension and clinical errors in practice. Data evaluating “Implications” included low error rates in practice. Interpreting our findings according to Kane’s framework, we suggest the evidence for scoring, generalization and implications supports use of our simulation-based paramedic assessment strategy as a certifying exam; however, the extrapolation evidence was weak, suggesting exam scores did not predict clinical error rates. Our analysis represents a worked example others can follow when using Kane’s validity framework to evaluate, and iteratively develop and refine assessment strategies.  相似文献   
996.
997.
Quality of Life Research - Researchers investigating person-centredness in older people’s long-term community care are hindered by the lack of appropriate measures. Studies have tended to...  相似文献   
998.
In the context of global population ageing, the reconciliation of employment and unpaid caring is becoming an important social issue. The estimation of the public expenditure costs of carers leaving employment is a valuable measure that is of considerable interest to policy makers. In 2012, the Personal Social Services Research Unit estimated that the public expenditure costs of unpaid carers leaving employment in England were approximately £1.3 billion a year, based on the costs of Carer's Allowance and lost tax revenues on forgone incomes. However, this figure was known to be an underestimate partly because it did not include other key benefits that carers who have given up work to care may receive. This paper presents a new estimate of the public expenditure costs of carers leaving employment. Key sources of information are the 2009/2010 Survey of Carers in Households, 2011 Census and 2015/2016 costs data. As well as Carer's Allowance, the estimate also now includes the costs of other benefits that carers leaving work may receive, namely, Income Support and Housing Benefit. The results show that the estimated numbers of carers who have left employment because of caring have increased from approximately 315,000 to 345,000. Due mainly to the inclusion of a wider range of benefits, the public expenditure costs of carers leaving employment in England are now estimated at £2.9 billion a year. The new estimate comprises £1.7 billion in social security benefits paid to people who have left their jobs because of unpaid caring, plus another £1.2 billion in taxes forgone on this group's lost earnings. The paper concludes that, if there was greater public investment in social care, such as “replacement care” to support carers in employment, and fewer carers then left employment, public spending on benefits would be lower and revenues from taxation would be higher.  相似文献   
999.
Background: To make a proper causality assessment of an adverse drug reaction (ADR) report, a certain level of clinical information is necessary. A tool was developed to measure the level of clinical information present in ADR reports. The aim of this study was to test the validity and reliability of the clinical documentation tool (ClinDoc) in an international setting.

Methods: The tool was developed by a panel of pharmacovigilance experts. It includes four domains: ADR, chronology of the ADR, suspected drug and patient characteristics. The final score categorizes reports into: excellent, well, moderately or poorly documented.

In two rounds, eight pharmacovigilance assessors of different countries made a total of 224 assessments using the tool, with the expert panels judgement as a standard. Sensitivity and specificity were calculated.

Results: The tool with four outcome-categories demonstrated low sensitivity. A lack of distinctiveness was demonstrated between the categories moderate and well. Results for the second round were re-analysed using three categories. This demonstrated a better validity.

Conclusion: This is the first tool to give insight in the level of relevant clinical information present in ADR reports. It can be used internationally to compare reports coming from different reporting methods and different types of reporters in pharmacovigilance.  相似文献   

1000.
Proximal tubules in the kidney play a crucial role in reabsorbing and eliminating substrates from the body into the urine, leading to high local concentrations of xenobiotics. This makes the proximal tubule a major target for drug toxicity that needs to be evaluated during the drug development process. Here, we describe an advanced in vitro model consisting of fully polarized renal proximal tubular epithelial cells cultured in a microfluidic system. Up to 40 leak-tight tubules were cultured on this platform that provides access to the basolateral as well as the apical side of the epithelial cells. Exposure to the nephrotoxicant cisplatin caused a dose-dependent disruption of the epithelial barrier, a decrease in viability, an increase in effluent LDH activity, and changes in expression of tight-junction marker zona-occludence 1, actin, and DNA-damage marker H2A.X, as detected by immunostaining. Activity and inhibition of the efflux pumps P-glycoprotein (P-gp) and multidrug resistance protein (MRP) were demonstrated using fluorescence-based transporter assays. In addition, the transepithelial transport function from the basolateral to the apical side of the proximal tubule was studied. The apparent permeability of the fluorescent P-gp substrate rhodamine 123 was decreased by 35% by co-incubation with cyclosporin A. Furthermore, the activity of the glucose transporter SGLT2 was demonstrated using the fluorescent glucose analog 6-NBDG which was sensitive to inhibition by phlorizin. Our results demonstrate that we developed a functional 3D perfused proximal tubule model with advanced renal epithelial characteristics that can be used for drug screening studies.  相似文献   
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