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Background

It has recently been suggested that myocardial oedema follows a bimodal pattern early post ST-segment elevation myocardial infarction (STEMI). Yet, water content, quantified using tissue desiccation, did not return to normal values unlike oedema quantified by cardiovascular magnetic resonance (CMR) imaging. We studied the temporal changes in the extent and intensity of injured myocardium using T1-mapping technique within the first week after STEMI.

Methods

A first group (n?=?31) underwent 3 acute 3?T CMR scans (time-point (TP) <?3?h, 24?h and 6?days), including cine, native shortened modified look-locker inversion recovery T1 mapping, T2* mapping and late gadolinium enhancement (LGE). A second group (n?=?17) had a single scan at 24?h with an additional T2-weighted sequence to assess the difference in the extent of area-at-risk (AAR) compared to T1-mapping.

Results

The mean T1 relaxation time value within the AAR of the first group was reduced after 24?h (P?<?0.001 for TP1 vs.TP2) and subsequently increased at 6?days (P?=?0.041 for TP2 vs.TP3). However, the extent of AAR quantified using T1-mapping did not follow the same course, and no change was detected between TP1&TP2 (P?=?1.0) but was between TP2 &TP3 (P?=?0.019). In the second group, the extent of AAR was significantly larger on T1-mapping compared to T2-weighted (42?±?15% vs. 39?±?15%, P?=?0.025). No change in LGE was detected while microvascular obstruction and intra-myocardial haemorrhage peaked at different time points within the first week of reperfusion.

Conclusion

The intensity of oedema post-STEMI followed a bimodal pattern; while the extent of AAR did not track the same course. This discrepancy has implications for use of CMR in this context and may explain the previously reported disagreement between oedema quantified by imaging and tissue desiccation.
  相似文献   
95.
Evidence on the use of simulation to teach psychiatry and mental health (including addiction) content is emerging, yet no summary of the implementation processes or associated outcomes exists. The aim of this study was to systematically search and review empirical literature on the use of psychiatry‐focused simulation in undergraduate nursing education. Objectives were to (i) assess the methodological quality of existing evidence on the use of simulation to teach mental health content to undergraduate nursing students, (ii) describe the operationalization of the simulations, and (iii) summarize the associated quantitative and qualitative outcomes. We conducted online database (MEDLINE, Embase, ERIC, CINAHL, PsycINFO from January 2004 to October 2015) and grey literature searches. Thirty‐two simulation studies were identified describing and evaluating six types of simulations (standardized patients, audio simulations, high‐fidelity simulators, virtual world, multimodal, and tabletop). Overall, 2724 participants were included in the studies. Studies reflected a limited number of intervention designs, and outcomes were evaluated with qualitative and quantitative methods incorporating a variety of tools. Results indicated that simulation was effective in reducing student anxiety and improving their knowledge, empathy, communication, and confidence. The summarized qualitative findings all supported the benefit of simulation; however, more research is needed to assess the comparative effectiveness of the types of simulations. Recommendations from the findings include the development of guidelines for educators to deliver each simulation component (briefing, active simulation, debriefing). Finally, consensus around appropriate training of facilitators is needed, as is consistent and agreed upon simulation terminology.  相似文献   
96.
The purpose of this study was to determine whether nitrate supplementation augments cutaneous reactive hyperaemia. Seven participants were tested pre‐ and postnitrate supplementation (25 ml beetroot juice); participants consumed one shot per day for 3 days. Participants were instrumented with two microdialysis fibres: control (Ringer's solution) and NO synthase inhibition (20 mM L‐NAME). Skin blood flow was measured via laser‐Doppler flowmetry (LDF). A blood pressure cuff was placed on the experimental arm and inflated to 250 mmHg for 5 mins to occlude arterial inflow. The cuff was released, and the resultant reactive hyperaemia was measured. Blood pressure was continuously measured via plethysmography from a finger on the non‐experimental arm. Cutaneous vascular conductance was calculated (LDF/MAP) and normalized to maximal vasodilatation (%CVCmax). Only diastolic blood pressure was reduced following nitrate supplementation (71 ± 2 vs. 66 ± 1 mmHg; P<0·05). There was no effect of nitrate supplementation on peak reactive hyperaemia at control (Pre: 52 ± 3 vs. Post: 57 ± 2%CVCmax) or L‐NAME (Pre: 52 ± 2 vs. Post: 59 ± 4%CVCmax) sites. There was no effect of nitrate supplementation on total reactive hyperaemia at either control (Pre: 4197 ± 943 vs. Post: 4523 ± 1040%CVCmax * sec) or L‐NAME (Pre: 5108 ± 997 vs. Post: 5694 ± 1002%CVCmax * sec) sites. These data suggest cutaneous reactive hyperaemia is unaffected by dietary nitrate supplementation in healthy humans.  相似文献   
97.
To meet the goals of the National HIV/AIDS Strategy and the need for a human immunodeficiency virus (HIV)-competent primary care workforce, education and training of nurse practitioners are critical. The University of California, San Francisco School of Nursing developed and implemented an HIV primary care curriculum and evaluated this curriculum for a graduating cohort of 55 students. Results show gains in students’ HIV knowledge and confidence in providing basic HIV care and improvements in attitudes toward people living with HIV. We have been able to show that HIV content can be successfully integrated into a nurse practitioner generalist curriculum.  相似文献   
98.

Purpose

The aim of the present study was to evaluate the efficacy of an oral formulation of Δ9-tetrahydrocannabinol (ECP002A) in patients with progressive multiple sclerosis (MS).

Methods

This accelerated proof-of-concept study consisted of 2 phases: a crossover challenge (dose-finding) phase and a 4-week, parallel, randomized, placebo-controlled treatment phase. Twenty-four patients with progressive MS and moderate spasticity were enrolled. During the treatment phase, biomarkers for efficacy and secondary pharmacodynamic effects were measured at baseline and after 2 and 4 weeks of treatment. Serum samples were collected to determine pharmacokinetic properties and perform population modeling. Safety and tolerability profiles were assessed based on adverse events and safety measurements.

Findings

Pain was significantly reduced when measured directly after administration of ECP002A in the clinic but not when measured in a daily diary. A similar pattern was observed in subjective muscle spasticity. Other clinical outcomes were not significantly different between active treatment and placebo. Cognitive testing indicated that there was no decline in cognition after 2 or 4 weeks of treatment attributable to ECP002A compared with placebo.ImplicationsThis study specifically underlines the added value of thorough investigation of pharmacokinetic and pharmacodynamic associations in the target population. Despite the complex interplay of psychoactive effects and analgesia, the current oral formulation of Δ9-tetrahydrocannabinol may play a role in the treatment of spasticity and pain associated with MS because it was well tolerated and had a stable pharmacokinetic profile.  相似文献   
99.
In the past few years we have become increasingly aware of strong associations between obesity and ADHD. Both conditions are major public health issues, affecting children, adolescents and adults alike.

Objective

This review seeks to (1) examine prior research on the association between ADHD and obesity in children and adolescents; (2) discuss mechanisms and consequent behavioral attributes to gain understanding of the path association between ADHD and obesity, (3) review studies examining the role of physical activity, medication, eating behavior and gender on the relationship between ADHD and obesity in children and adolescents.

Method

PubMed, CINAHL and PsycINFO databases were used to search for studies whose subjects were children and adolescents, ages 0–17?years and whose publication years were from 2000 to 2016. After screening 31 studies were included in the review.

Results

The literature suggests that there is a significant association between ADHD and obesity. Further, the inattentive and impulsive behaviors that characterize ADHD could contribute to dis-regulated eating behaviors and a lack of motivation to engage in physical activity. In addition, it is proposed that medication, gender and physical activity play a role in mediating and moderating the relationship between ADHD and obesity.  相似文献   
100.
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