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101.
A regulatory module embedded in the coding region of Hoxa2 controls expression in rhombomere 2 总被引:1,自引:1,他引:1
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Stefan Tümpel Francisco Cambronero Carrie Sims Robb Krumlauf Leanne M. Wiedemann 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(51):20077-20082
Here, we define a gene regulatory network for Hoxa2, responsible for temporal and spatial expression in hindbrain development. Hoxa2 plays an important role in regulating the regional identity of rhombomere 2 (r2) and is the only Hox gene expressed in this segment. In this study, we found that a Hoxa2 cis-regulatory module consists of five elements that direct expression in r2 of the developing hindbrain. Surprisingly, the module is imbedded in the second coding exon of Hoxa2 and therefore may be constrained by both protein coding and gene regulatory requirements. This highly conserved enhancer consists of two consensus Sox binding sites and several additional elements that act in concert to direct strong r2 specific expression. Our findings provide important insight into the regulation of segmental identity in the anterior hindbrain. Furthermore, they have broader implications in designing arrays and interpreting data from global analyses of gene regulation because regulatory input from coding regions needs to be considered. 相似文献
102.
Leanne Streja Catherine M. Crespi Roshan Bastani Glenn C. Wong Craig A. Jones John T. Bernert Donald Tashkin S. Katharine Hammond Barbara A. Berman 《Journal of immigrant and minority health / Center for Minority Public Health》2014,16(2):256-264
We report on the results of a low-intensity behavioral intervention to reduce second hand smoke (SHS) exposure of children with asthma from low income minority households in Los Angeles, California. In this study, 242 child/adult dyads were randomized to a behavioral intervention (video, workbook, minimal counseling) or control condition (brochure). Main outcome measures included child’s urine cotinine and parental reports of child’s hours of SHS exposure and number of household cigarettes smoked. Implementation of household bans was also considered. No differences in outcomes were detected between intervention and control groups at follow-up. Limitations included high attrition and low rates of collection of objective measures (few children with urine cotinine samples). There continues to be a need for effective culturally and linguistically appropriate strategies that support reduction of household SHS exposure among children with asthma in low income, minority households. 相似文献
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Cathleen Taylor Karen Croot Emma Power Sharon A. Savage John R. Hodges Leanne Togher 《Aphasiology》2014,28(8-9):1069-1091
Background: Primary progressive aphasia (PPA) affects a range of language domains that impact on communication. Little is known about the nature of conversation breakdown in PPA. The identification of trouble in conversation, its repair and the success of repairs has been used effectively to examine conversation breakdown in neurogenic language disorders such as dementia of the Alzheimer type (DAT) and acute onset aphasia. This study investigated trouble and repair in the conversations of people with PPA.Aims: The first aim of this study is to describe the contributions of individuals with PPA and their conversation partner to conversation. The second aim is to describe the trouble that occurs in dyadic conversations between three individuals with PPA and their communication partner. The third aim is to describe the repair behaviours used by the individuals with PPA and their communication partners.Methods & Procedures: Dyadic conversations about everyday activities between three individuals with PPA and their partners and three control dyads were video recorded and transcribed. Number of words, number of turns and length of turns were measured and trouble-indicating behaviours (TIBs) and repair behaviours were categorised.Outcomes & Results: Individuals with PPA had reduced mean length of turn but maintained their share of turn-taking. They demonstrated a variety of TIBs that differed from the noninteractive repairs, which do not require a response from the partner in the conversation and which have been observed in studies of conversation in DAT. Their partners bore the greater burden of highlighting trouble and need for repair using collaborative, interactive, TIBs. Three different conversational profiles were observed in the three PPA dyads, reflecting different patterns of language and cognitive impairment.Conclusions: Individuals with PPA were active participants in conversation effectively indicating and responding to trouble. Understanding trouble and repair in the conversations of individuals with PPA has the potential to enhance assessment and inform clinical practice. 相似文献
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Kerry Siminoski Brian Lentle Mary Ann Matzinger Nazih Shenouda Leanne M. Ward 《Pediatric radiology》2014,44(4):457-466
Background
The Genant semiquantitative (GSQ) method has been a standard procedure for diagnosis of vertebral fractures in adults but has only recently been shown to be of clinical utility in children. Observer agreement using the GSQ method in this age group has not been described.Objective
To evaluate observer agreement on vertebral readability and vertebral fracture diagnosis using the GSQ method in pediatric vertebral morphometry.Materials and methods
Spine radiographs of 186 children with acute lymphoblastic leukemia were evaluated independently by three radiologists using the same GSQ methodology as in adults. A subset of 100 radiographs was evaluated on two occasions.Results
An average of 4.7% of vertebrae were unreadable for the three radiologists. Intraobserver Cohen’s kappa (κ) on readability ranged from 0.434 to 0.648 at the vertebral level and from 0.416 to 0.611 at the patient level, while interobserver κ for readability had a range of 0.330 to 0.504 at the vertebral level and 0.295 to 0.467 at the patient level. Intraobserver κ for the presence of vertebral fracture had a range of 0.529 to 0.726 at the vertebral level and was 0.528 to 0.767 at the patient level. Interobserver κ for fracture at the vertebral level ranged from 0.455 to 0.548 and from 0.433 to 0.486 at the patient level.Conclusion
Most κ values for both intra- and interobserver agreement in applying the GSQ method to pediatric spine radiographs were in the moderate to substantial range, comparable to the performance of the technique in adult studies. The GSQ method should be considered for use in pediatric research and clinical practice. 相似文献109.