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951.
The growing problem of antibiotic resistant bacteria, along with a dearth of new antibiotics, has redirected attention to the search for alternative antimicrobial agents. Conjugated oligoelectrolytes (COEs) are an emerging class of antimicrobial agents which insert into bacterial cell membranes and are inhibitory against a range of Gram-positive and Gram-negative bacteria. In this study, the extent of COE resistance that Enterococcus faecalis could achieve was studied. Enterococci are able to grow in hostile environments and develop resistance to membrane targeting antibiotics such as daptomycin in clinical settings. Herein we expand our knowledge of the antimicrobial mechanism of action of COEs by developing COE-resistant strains of E. faecalis OG1RF. Evolution studies yielded strains with a moderate 4–16 fold increase in antimicrobial resistance relative to the wild type. The resistant isolates accumulated agent-specific mutations associated with the liaFSR operon, which is a cell envelope-associated stress-response sensing and regulating system. The COE resistant isolates displayed significantly altered membrane fatty acid composition. Subsequent, exogenous supplementation with single fatty acids, which were chosen based on those dominating the fatty acid profiles of the mutants, increased resistance of the wild-type E. faecalis to COEs. In combination, genetic, fatty acid, and uptake studies support the hypothesis that COEs function through insertion into and disruption of membranes and that the mechanism by which this occurs is specific to the disrupting agent. These results were validated by a series of biophysical experiments showing the tendency of COEs to accumulate in and perturb adapted membrane extracts. Collectively, the data support that COEs are promising antimicrobial agents for targeting E. faecalis, and that there is a high barrier to the emergence of severely resistant strains constrained by biological limits of membrane remodeling that can occur in E. faecalis.

COEs are emerging antimicrobials to combat drug resistant infections and to which bacteria develop only limited resistance.  相似文献   
952.
Purpose: To conduct a literature review identifying barriers and facilitators students with physical disabilities (SwD-P) may encounter in science and engineering (S&E) laboratories.

Method: Publications were identified from 1991 to 2015 in ERIC, web of science via web of knowledge, CINAHL, SCOPUS, IEEEXplore, engineering village, business source complete and PubMed databases using search terms and synonyms for accommodations, advanced manufacturing, additive manufacturing, assistive technology (AT), barriers, engineering, facilitators, instructor, laboratory, STEM education, science, students with disabilities and technology.

Results: Twenty-two of the 233 publications that met the review’s inclusion criteria were examined. Barriers and facilitators were grouped based on the international classification of functioning, disability and health framework (ICF). None of the studies directly found barriers or facilitators to SwD-P in science or engineering laboratories within postsecondary environments. The literature is not clear on the issues specifically related to SwD-P.

Conclusion: Given these findings, further research (e.g., surveys or interviews) should be conducted to identify more details to obtain more substantial information on the barriers that may prevent SwD-P from fully participating in S&E instructional laboratories.

  • Implications for Rehabilitation
  • Students with disabilities remain underrepresented going into STEM careers.

  • A need exist to help uncover barriers students with disabilities encounter in STEM laboratory.

  • Environments.

  • Accommodations and strategies that facilitate participation in STEM laboratory environments are promising for students with disabilities

  相似文献   
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Background

Ultrasound guidance is increasingly being used for neurolytic procedures that have traditionally been done with electrical stimulation (e-stim) guidance alone. Ultrasound visualization with e-stim?guided neurolysis can potentially allow adjustments in injection protocols that will reduce the volume of neurolytic agent needed to achieve clinical improvement.

Objective

This study compared e-stim only to e-stim with ultrasound guidance in phenol neurolysis of the musculocutaneous nerve (MCN) for elbow flexor spasticity. We also evaluated the ultrasound appearance of the MCN in this population.

Design

Retrospective review.

Setting

University hospital outpatient clinic.

Participants

Adults (N = 167) receiving phenol neurolysis to the MCN for treatment of elbow flexor spasticity between 1997 and 2014 and adult control subjects.

Methods

For each phenol injection of the MCN, the method of guidance, volume of phenol injected, technical success, improved range of motion at the elbow postinjection, adverse effects, reason for termination of injections, and details of concomitant botulinum toxin injection were recorded. The ultrasound appearance of the MCN, including nerve cross-sectional area and shape, were recorded and compared between groups.

Main Outcome Measures

The volume of phenol injected and MCN cross-sectional area and shape as demonstrated by ultrasound.

Results

The addition of ultrasound to e-stim?guided phenol neurolysis was associated with lower doses of phenol when compared to e-stim guidance alone (2.31 mL versus 3.69 mL, P < .001). With subsequent injections, the dose of phenol increased with e-stim guidance (P < .001), but not with e-stim and ultrasound guidance (P = .95). Both methods of guidance had high technical success, improved ROM at elbow postinjection, and low rates of adverse events. In comparing the ultrasound appearance of the MCN in patients with spasticity to that of normal controls, there was no difference in the cross-sectional area of the nerve, but there was more variability in shape.

Conclusions

Combined e-stim and ultrasound guidance during phenol neurolysis to the MCN allows a smaller volume of phenol to be used for equal effect, both at initial and repeat injection. The MCN shape was more variable in individuals with spasticity; this should be recognized so as to successfully locate the nerve to perform neurolysis.

Level of Evidence

IV  相似文献   
955.
956.
The aim of this study was to compare the influence of two different instructional climates on the accumulation of moderate-to-vigorous physical activity (MVPA) during a fully-inclusive adapted recreational physical activity program. A total of 32 children (18 typically-developing (TD), and 14 with developmental disabilities (DD) ranging in ages from 5 to 9 years, participated in six, 60-min adapted recreational sessions. Of those six sessions, three incorporated an autonomy-supportive climate (high autonomy), and three incorporated direct instruction (low autonomy). MVPA was measured using accelerometers. A repeated measures ANOVA was conducted to determine significant differences in MVPA between group (TD/DD), climate (autonomy/direct), and a group x climate interaction. Significant group and climate main effects were observed (p?=?0.002 and 0.014, respectively). However, there was not a significant group x climate interaction (p?=?0.313). These results suggest that although the group of children with disabilities spent less time in MVPA compared to their typically-developing peers, all participants spent more time in MVPA for the autonomy-supportive climate compared to the low-autonomous climate. This study is the first to quantitatively assess the efficacy of a fully-inclusive autonomy-supportive climate on physical activity levels in children with and without developmental disabilities.  相似文献   
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958.
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Delirium, a common syndrome in terminally ill people, presents specific challenges to a good death in end‐of‐life care. This paper examines the relational engagement between hospice nurses and their patients in a context of end‐of‐life delirium. Ethnographic fieldwork spanning 15 months was conducted at a freestanding residential hospice in eastern Canada. A shared value system was apparent within the nursing community of hospice; patients’ comfort and dignity were deemed most at stake and therefore commanded nurses’ primary attention. This overarching commitment to comfort and dignity shaped all of nursing practice in this hospice, including practices related to end‐of‐life delirium. The findings of this study elaborate the ways in which hospice nurses interpreted and responded to the discomfort of their patients in delirium, as well as the efforts they made to understand their patients’ subjective experiences and to connect with them in supportive ways. In addition to what is already known about clinical assessment and treatment of delirium in palliative care settings, the findings of this study offer points of reflection for nurses anywhere who are contending with the relational challenges that delirium presents in end‐of‐life care.  相似文献   
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