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Li Jin Nicole E. Hastings Brett R. Blackman Avril V. Somlyo 《Journal of muscle research and cell motility》2009,30(1-2):41-55
Lipoma preferred partner (LPP) localizes to focal adhesions/dense bodies, is selectively expressed in smooth muscle cells (SMC) and enhances cell migration. SMCs cultured on denatured collagen or on a rigid substrate, up regulated expression of LPP, its partner palladin, tenascin C (TN-C), phosphorylated focal adhesion kinase (pFAK) and exhibited robust stress fibers. In an endothelial (EC)/SMC hemodynamic flow system, shear stress waveforms mimicking atheroprone flow, applied to the EC layer, significantly decreased expression of SMC LPP and palladin. They were also down regulated with TN-C, in an ApoE murine model of atherosclerosis and with oxidative stress but up regulated in an arterial injury model in response to upstream sequential changes in pFAK, Prx1 and TN-C. In conclusion, expression of LPP and palladin are modulated by a mix of mechanical cues, oxidative stress and substrate composition which translate into their up or down regulation in vessel wall injury and early atherogenesis. 相似文献
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Elizabeth E. McNeill Nicole L. Hines Regina Phariss 《Journal of the Association for Vascular Access》2009,14(1):46-51
The objectives of this survey were to: 1) understand current peripheral IV stabilization practices within our hospital and 2) evaluate the use of a new closed IV catheter system with a built-in stabilization platform. All medical-surgical patients within an 851-bed acute care hospital with peripheral-short catheters were evaluated within a 3-day period for catheter securement, dwell time, and signs of complications. Additionally, catheter restart data were collected from a renal telemetry unit for 2 weeks. Catheter and dressing protocols were then standardized to a new catheter system with a built-in stabilization platform (Nexiva? Closed Catheter System) and an absorbent transparent dressing (SorbaView® 2000). After a 2-week trial of the new protocol, catheters were again evaluated for securement and restart data were again collected from the renal telemetry unit. Staff nurse (N = 42) opinions on the new catheter system and dressing combination were sought, as well as a vote on willingness to change to the new catheter system and dressing. Results demonstrate improvement in catheter stabilization (out to 96 hours of dwell-time), decreased restarts, a high clinical preference for the new catheter/dressing system, and a high willingness to convert to the new system. Results indicate that the new closed IV catheter system with a built-in stabilization platform and the transparent absorbent dressing evaluated in this survey may help to improve catheter securement and increase dwell-time. Research studies utilizing more rigorous randomized, controlled comparisons are warranted. 相似文献
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Vicki Bacidore Nicole Warren Christine Chaput Vicki A. Keough 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》2009,38(6):730-738
The purpose of this article is to examine how nurses can improve comprehensive care for women who suffer an early pregnancy loss in the emergency department and highlight the integral role of obstetric and emergency department nurses within a new holistic framework of collaborative care. These nurses are integral in the proposed collaborative "fetal loss framework," which provides an innovative approach for holistic care for this population. 相似文献
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Darlene A. Kertes Bonny Donzella Nicole M. Talge Melissa C. Garvin Mark J. Van Ryzin Megan R. Gunnar 《Developmental psychobiology》2009,51(7):521-532
Preschool‐aged children (n = 274) were examined in the laboratory to assess behavioral and cortisol responses to nonsocial and social threat. Parents also responded to scales on the Children's Behavior Questionnaire reflecting exuberant approach to novel/risky activities (reversed scored) and shyness. Multi‐method measures of Nonsocial and Social Inhibition were computed. Parents and children were observed engaging in a series of interactive tasks and the Emotional Availability scales were scored for parental sensitivity, nonintrusiveness, nonhostility, and structuring. These scores were factored to yield one measure of Parenting Quality. Analyses revealed that Nonsocial and Social Inhibition could be distinguished and that associations with cortisol response were stressor specific. Moderation analyses revealed that parenting quality buffered cortisol elevations for extremely socially, but not nonsocially inhibited children. These findings are consistent with evidence that sensitive, supportive parenting is an important buffer of the HPA axis response to threat in infants and toddlers, and extends this finding to the preschool period. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 521–532, 2009. 相似文献
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Michael L. Reno Nicole L. Held Christopher J. Fields Patricia V. Burke Rachel J. Whitaker 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(21):8605-8610
Variation in gene content has been hypothesized to be the primary mode of adaptive evolution in microorganisms; however, very little is known about the spatial and temporal distribution of variable genes. Through population-scale comparative genomics of 7 Sulfolobus islandicus genomes from 3 locations, we demonstrate the biogeographical structure of the pan-genome of this species, with no evidence of gene flow between geographically isolated populations. The evolutionary independence of each population allowed us to assess genome dynamics over very recent evolutionary time, beginning ≈910,000 years ago. On this time scale, genome variation largely consists of recent strain-specific integration of mobile elements. Localized sectors of parallel gene loss are identified; however, the balance between the gain and loss of genetic material suggests that S. islandicus genomes acquire material slowly over time, primarily from closely related Sulfolobus species. Examination of the genome dynamics through population genomics in S. islandicus exposes the process of allopatric speciation in thermophilic Archaea and brings us closer to a generalized framework for understanding microbial genome evolution in a spatial context. 相似文献