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1.
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
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Introduction/Hypothesis

Recruitment of participants into phase 1 vaccine clinical trials can be challenging since these vaccines have not been used in humans and there is no perceived benefit to the participant. Occasionally, as was the case with a phase 1 clinical trial of an Ebola vaccine in Halifax, Canada, during the 2014–2016 West African Ebola virus outbreak, recruitment is less difficult. In this study, we explored the motivations of participants in two phase 1 vaccine trials that were concurrently enrolling at the same centre and compared the motivations of participants in a high-profile phase 1 Ebola vaccine trial to those in a less high-profile phase 1 adjuvanted seasonal influenza vaccine study.

Methods

An online survey which included participants’ prior experience with clinical trials, motivations to participate (including financial incentives), and demographic information was developed to examine the motivations of healthy participants in two phase 1 clinical vaccine trials conducted at the Canadian Center for Vaccinology in Halifax, Nova Scotia. Participants were invited via email to complete the online survey. Readability and clarity were assessed through pilot testing.

Results

A total of 49 (55.7%) of 88 participants of the two studies completed the survey (22 [55%] of 40 participants from the Ebola vaccine study and 27 [56.3%] of 48 from the adjuvanted influenza vaccine study). Motivations that were most frequently ranked among participants' top three in both trials were (1) wanting to contribute to the health of others, (2) wanting to participate in something important, (3) wanting to contribute to the advancement of science, and (4) wanting to receive an incentive such as money or a tablet.

Conclusions/Recommendations

Although media attention and financial compensation were more often cited by Ebola vaccine trial participants as a reason to participate, both altruistic and self-interested factors were important motivations for participants in their decision to participate in a phase 1 vaccine clinical trial.  相似文献   
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  1. The metabolism of the pyrethroids deltamethrin (DLM), cis-permethrin (CPM) and trans-permethrin (TPM) was studied in human expressed cytochrome P450 (CYP) and carboxylesterase (CES) enzymes.

  2. DLM, CPM and TPM were metabolised by human CYP2B6 and CYP2C19, with the highest apparent intrinsic clearance (CLint) values for pyrethroid metabolism being observed with CYP2C19. Other CYP enzymes contributing to the metabolism of one or more of the three pyrethroids were CYP1A2, CYP2C8, CYP2C9*1, CYP2D6*1, CYP3A4 and CYP3A5. None of the pyrethroids were metabolised by CYP2A6, CYP2E1, CYP3A7 or CYP4A11.

  3. DLM, CPM and TPM were metabolised by both human CES1 and CES2 enzymes.

  4. Apparent CLint values for pyrethroid metabolism by CYP and CES enzymes were scaled to per gram of adult human liver using abundance values for microsomal CYP enzymes and for CES enzymes in liver microsomes and cytosol. TPM had the highest and CPM the lowest apparent CLint values for total metabolism (CYP and CES enzymes) per gram of adult human liver.

  5. Due to their higher abundance, all three pyrethroids were extensively metabolised by CES enzymes in adult human liver, with CYP enzymes only accounting for 2%, 10% and 1% of total metabolism for DLM, CPM and TPM, respectively.

  相似文献   
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Background

Schizophrenia is a chronic mental illness that affects the client, family, and community. Nurses are educated to use the nurse-patient relationship to provide health education and collaborative health decision-making. However, challenges abound for nurses and clients with schizophrenia to effectively utilize the relationship to reach these goals.

Problem

There is a lack of evidence-based information to assist nurses to meet the challenges of building effective therapeutic relationships with clients for whom schizophrenia hinders health education and decision-making.

Purpose

To examine current research findings on factors that influence therapeutic relationships in psychiatric treatment settings as an initial effort to provide empirically based guidance for psychiatric nurses who seek to better use the relationship to work with the client toward health-related goals.

Method

This integrative review of the literature follows Whittemore and Knafl's (2015) method, analyzes 15 studies from multiple databases between the years 2006–2017, and assesses the rigor of each.

Findings

Numerous methods are used to assess therapeutic relationships. Few studies included nurses. Provider perception of client symptoms can negatively affect provider assessment of quality of relationship; no such association was found on the part of clients. Providers and clients prioritize client needs differently, with providers influenced by treatment setting demands, but provider-training programs can have a beneficial effect on their relationships.

Conclusion

Nurses and nurse educators can use the findings to guide assessment of how perceptions and priorities influence relationships. Findings also provide the foundation for further study of nurses' perceptions of therapeutic relationship, in progress, to yield more detailed information on what nurses and educators need to strengthen therapeutic relationships.  相似文献   
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This is the third and final part of a series of articles that report the findings of a study that investigated the effects of a summer externship program on the transition into a professional role among nurses who participated in a summer nurse externship program at an acute care pediatric hospital. Specifically, this article reports the retention and recruitment benefits of a summer nurse externship program for the institution from 1998 through 2003. A total of 153 externs out of the 193 (79.0%) assumed a registered nurse position at the institution, and 77% remained in that role for 12 months. Overall, the nurse extern program for this institution appeared to be an effective recruitment and retention strategy that is on par with the institution and national data for retention and turnover data.  相似文献   
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OBJECTIVES: To pilot the acceptability and feasibility of clinical audit in free and pedicled flap reconstruction. To establish a baseline flap failure rate in participating units, so that a sample size calculation could be performed for future national audit. METHODS: A proforma was piloted over a 3-month period in four participating units, during which time data on 93 reconstructive procedures involving free and pedicled flaps was collected. The patients included those where large transfers of tissue were required such as for coverage of grade IIIb compound tibial fractures and breast reconstruction after mastectomy, and also smaller flap transfers such as after skin cancer excision. RESULTS: The proforma was found to be acceptable to clinicians and the feasibility of the data collection process was established. Overall there was a total flap survival of 89% and secondary operations to the donor or recipient sites were required in 11% of patients. CONCLUSIONS: This study demonstrates the feasibility of comparative audit for free and pedicled flap procedures using the methods proposed. Based on the incidence of flap failure observed in this pilot study, at least 18 months of prospective data collection on consecutive patients is required to fulfil the statistical requirements of comparative audit. The establishment of a routinely collected minimum dataset is proposed as one means of meeting these requirements.  相似文献   
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