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81.
Focal ischemic chondronecrosis of epiphyseal growth cartilage (EGC) during endochondral ossification is believed to be a key early event on the pathway to osteochondrosis (OC) in both animals and humans. The lateral ridge of the equine trochlea is a site where severe osteochondritis dissecans lesions frequently arise and is a model for the study of naturally occurring disease. Non‐invasive imaging to investigate EGC vascularity may help elucidate why focal ischemia occurs. 3T MRI susceptibility‐weighted imaging (SWI) of femoral trochlea of OC predisposed (n = 10) and control (n = 6) day‐old foals, with minimal joint loading after birth, was performed. SWI and 3D images revealed the EGC vascular architecture without a contrast agent, and matched histologic observations. No vascular lesions were identified. There was no difference in the vascular density and architecture between control and OC specimens, but a striking difference in vascular pattern was seen at the OC‐predilected site in the lateral ridge of the trochlea in all specimens, when compared to the medial ridge of the trochlea, where OC lesions are rarely observed. This site was less ossified with more perichondrial vessels not yet bridging with the subchondral bone. Furthermore, the mean vascular density of all specimens was significantly higher at this site. We speculate that joint morphology and focal internal trauma on this site with a unique vascular architecture may trigger ischemic events at this site. SWI permitted visualization of EGC in young foals with a clinical 3T MRI and paves the way for non‐destructive longitudinal studies to improve understanding of OC in all species. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1539–1546, 2016.  相似文献   
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Characterization of multiprotein complexes (MPCs) is an important step toward an integrative view of protein interaction networks and prerequisite for a molecular understanding of how a certain MPC functions. Here, we present a technique utilizing monoclonal subunit-specific antibodies for an electrophoretic immunoshift assay in Blue Native-gels (NAMOS-assay), which allows the determination of the stoichiometry of MPCs. First, we use the B cell antigen receptor as a model MPC whose stoichiometry is known, confirming the HC(2)LC(2)Igalpha/beta(1) stoichiometry. Second, we demonstrate that the digitonin-extracted T cell antigen receptor (TCR) extracted from T cells has a stoichiometry of alphabetaepsilon(2)gammadeltazeta(2). We then show that the NAMOS-assay does not require purified MPCs, since it can determine the stoichiometry of an MPC in cell lysates. The NAMOS-assay is also compatible with use of epitope tags appended to the protein of interest, as e.g. the widely used HA-tag, and anti-epitope antibodies for the assay. Given its general applicability, this method has a wide potential for MPC research.  相似文献   
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Emotional facial expressions have affective significance. Smiles, for example, are perceived as positive and responded to with increased happiness, whereas angry expressions are perceived as negative and threatening. Yet, these perceptions are modulated in part by facial morphological cues related to the sex of the expresser. The present research assessed both eyeblink startle and the postauricular reflex during happy and angry expressions by men and women. For this 14 male and 16 female undergraduates saw happy, neutral, and angry facial expressions as well as positive and negative pictures. The postauricular reflex was potentiated during happy expressions and inhibited during anger expressions; however, as expected, this pattern was more clearly found for female expressers. Conversely, the expected pattern of eyeblink startle potentiation during angry faces and inhibition during happy faces was found only for male expressers.  相似文献   
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Current low participation rates in vector control programmes in Arequipa, Peru complicate the control of Chagas disease. Using focus groups (n?=?17 participants) and semi-structured interviews (n?=?71) conducted in March and May 2013, respectively, we examined barriers to and motivators of household participation in an indoor residual spray (IRS) campaign that had taken place one year prior in Arequipa. The most common reported barriers to participation were inconvenient spray times due to work obligations, not considering the campaign to be necessary, concerns about secondary health impacts (e.g. allergic reactions to insecticides), and difficulties preparing the home for spraying (e.g. moving heavy furniture). There was also a low perception of risk for contracting Chagas disease that might affect participation. The main motivator to participate was to ensure personal health and well-being. Future IRS campaigns should incorporate more flexible hours, including weekends; provide appropriate educational messages to counter concerns about secondary health effects; incorporate peer educators to increase perceived risk to Chagas in community; obtain support from community members and leaders to build community trust and support for the campaign; and assist individuals in preparing their homes. Enhancing community trust in both the need for the campaign and its operations is key.  相似文献   
86.

Background

Sierra Leone’s health outcomes rank among the worst in the world. A major challenge is the shortage of primary healthcare workers (HCWs) in rural areas due to especially high rates of attrition. This study was undertaken to determine the drivers of job dissatisfaction and poor retention among Sierra Leone’s rural HCWs.

Methods

Interviews were conducted with 58 rural and 32 urban primary HCWs in Sierra Leone’s public health sector, complemented by key informant discussions and review of national policy documents. HCW interviews included (1) semi-structured discussion, (2) questionnaire, (3) card sort about HCW priorities, and (4) free-listing of most pressing challenges and needs. Sampling for HCW interviews was stratified purposive, emphasizing rural HCWs.

Results

Among 90 HCWs interviewed, 67% were dissatisfied with their jobs (71% rural vs 52% urban) and 61% intended to leave their post (75% rural vs 38% urban). While working and living conditions and remuneration were significant factors, a major reason for rural HCW disenchantment was their inability to access worker rights, benefits, and advancement opportunities. This was caused by HCWs’ lack of knowledge about human resource (HR) policies and procedures, as well as ambiguity in many policies and inequitable implementation. HCWs reported feeling neglected and marginalized and perceived a lack of transparency. These issues can be attributed to the absence of systems for regular two-way communication between the Ministry of Health and HCWs; lack of official national documents with up-to-date, clear HR policies and procedures for HCWs; pay statements that do not provide a breakdown of financial allowances and withholdings; and lack of HCW induction.

Conclusions

HCWs in Sierra Leone lacked accurate information about entitlements, policies, and procedures, and this was a driver of rural HCW job dissatisfaction and attrition. System-oriented, low-cost initiatives can address these underlying structural causes in Sierra Leone. These issues likely apply to other countries facing HCW retention challenges and should be considered in development of global HCW retention strategies.
  相似文献   
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BACKGROUNDThere is a lack of data on the clinical outcomes in patients with native valve infective endocarditis (NVIE) and diabetes mellitus (DM).AIMTo investigate (1) trends in the prevalence of DM among patients with NVIE; and (2) the impact of DM on NVIE outcomes. METHODSWe identified 76385 with NVIE from the 2004 to 2014 National Inpatient Sample, of which 22284 (28%) had DM. We assessed trends in DM from 2004 to 2014 using the Cochrane Armitage test. We compared baseline comorbidities, microorganisms, and in-patients procedures between those with vs without DM. Propensity match analysis and multivariate logistic regression were used to investigate study outcomes in in-hospital mortality, stroke, acute heart failure, cardiogenic shock, septic shock, and atrioventricular block.RESULTSCrude rates of DM increased from in 22% in 2004 to 30% in 2014. There were significant differences in demographics, comorbidities and NVIE risk factors between the two groups. Staphylococcus aureus was the most common organism identified with higher rates in patients with DM (33.1% vs 35.6%; P < 0.0001). After propensity matching, in-hospital mortality (11.1% vs 11.9%; P < 0.0001), stroke (2.3% vs 3.0%; P < 0.0001), acute heart failure (4.6% vs 6.5%; P = 0.001), cardiogenic shock (1.5% vs 1.9%; P < 0.0001), septic shock (7.2% vs 9.6%; P < 0.0001), and atrioventricular block (1.5% vs 2.4%; P < 0.0001), were significantly higher in patients with DM. Independent predictors of mortality in NVIE patients with DM include hemodialysis, congestive heart failure, atrial fibrillation, staphylococcus aureus, and older age.CONCLUSIONThere is an increasing prevalence of DM in NVIE and it is associated with poorer outcomes. Further studies are crucial to identify the clinical, and sociodemographic contributors to this trend and develop strategies to mitigate its attendant risk.  相似文献   
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