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941.
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944.
Undifferentiated nasopharyngeal carcinoma (NPC) is a cancer with high metastatic potential that is consistently associated with Epstein–Barr virus (EBV) infection. In this study, we have investigated the functional contribution of sphingosine‐1‐phosphate (S1P) signalling to the pathogenesis of NPC. We show that EBV infection or ectopic expression of the EBV‐encoded latent genes (EBNA1, LMP1, and LMP2A) can up‐regulate sphingosine kinase 1 (SPHK1), the key enzyme that produces S1P, in NPC cell lines. Exogenous addition of S1P promotes the migration of NPC cells through the activation of AKT; shRNA knockdown of SPHK1 resulted in a reduction in the levels of activated AKT and inhibition of cell migration. We also show that S1P receptor 3 (S1PR3) mRNA is overexpressed in EBV‐positive NPC patient‐derived xenografts and a subset of primary NPC tissues, and that knockdown of S1PR3 suppressed the activation of AKT and the S1P‐induced migration of NPC cells. Taken together, our data point to a central role for EBV in mediating the oncogenic effects of S1P in NPC and identify S1P signalling as a potential therapeutic target in this disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
945.
To conduct international comparisons of parent–adolescent cross-informant agreement in clinical samples, we analyzed ratings on the Child Behavior Checklist (CBCL) and Youth Self-Report (YSR) for 6,762 clinically referred adolescents ages 11–18 from 7 societies (M = 14.5 years, SD = 2.0 years; 51% boys). Using CBCL and YSR data, we asked the following questions: (a) Do parents report more problems for their adolescent children than the adolescents report about themselves? (b) How do cross-informant correlations (rs) for scale scores differ by problem type and by society? (c) How well do parents and adolescents, on average, agree regarding which problems they rate as low, medium, or high? (d) How does within-dyad item agreement vary within and between societies? (e) How do societies vary in dichotomous cross-informant agreement with respect to the deviance status of the adolescents? CBCL and YSR scores were quite similar, with small and inconsistent informant effects across societies. Cross-informant rs averaged .47 across scales and societies. On average, parents and adolescents agreed well regarding which problem items received low, medium, or high ratings (M r = .87). Mean within-dyad item agreement was moderate across all societies, but dyadic agreement varied widely within every society. In most societies, adolescent noncorroboration of parent-reported deviance was more common than parental noncorroboration of adolescent-reported deviance. Overall, somewhat better parent–adolescent agreement and more consistency in agreement patterns across diverse societies were found in these seven clinical samples than in population samples studied using the same methods.  相似文献   
946.
947.
Our understanding of Alzheimer’s disease (AD) is still incomplete and, as a result, we lack effective therapies. Reprogramming to generate human-induced pluripotent stem cells provides a new approach to the generation of human neurons that carry the genomes of people with familial or sporadic AD. Differentiation of such stem cells to human neurons is already providing new insights into AD and molecular pathways that may provide new targets for effective therapy. These pathways include typical amyloid response pathways, as well as pathways leading from altered behavior of amyloid precursor protein to the elevated phosphorylation of tau protein. There is also a need for standardization of models so that isogenic lines differing only in the familial AD mutation can be compared.

Electronic supplementary material

The online version of this article (doi:10.1007/s13311-014-0326-6) contains supplementary material, which is available to authorized users.  相似文献   
948.
Clostridium difficile PCR ribotype 033 (RT033) is found in the gastrointestinal tracts of production animals and, occasionally, humans. The illumigene C. difficile assay (Meridian Bioscience, Inc.) failed to detect any of 52 C. difficile RT033 isolates, while all strains signaled positive for the binary toxin genes but were reported as negative for C. difficile by the Xpert C. difficile/Epi assay (Cepheid).  相似文献   
949.
Pancreatic ductal adenocarcinoma (PDAC) is a genomically diverse, prevalent, and almost invariably fatal malignancy. Although conventional genetically engineered mouse models of human PDAC have been instrumental in understanding pancreatic cancer development, these models are much too labor-intensive, expensive, and slow to perform the extensive molecular analyses needed to adequately understand this disease. Here we demonstrate that retrograde pancreatic ductal injection of either adenoviral-Cre or lentiviral-Cre vectors allows titratable initiation of pancreatic neoplasias that progress into invasive and metastatic PDAC. To enable in vivo CRISPR/Cas9-mediated gene inactivation in the pancreas, we generated a Cre-regulated Cas9 allele and lentiviral vectors that express Cre and a single-guide RNA. CRISPR-mediated targeting of Lkb1 in combination with oncogenic Kras expression led to selection for inactivating genomic alterations, absence of Lkb1 protein, and rapid tumor growth that phenocopied Cre-mediated genetic deletion of Lkb1. This method will transform our ability to rapidly interrogate gene function during the development of this recalcitrant cancer.  相似文献   
950.

Background

Preterm birth complications are the leading cause of deaths for children under five years. Antenatal corticosteroids (ACS) are effective at reducing mortality and serious morbidity amongst infants born at <34 weeks gestation. WHO guidelines strongly recommend use of ACS for women at risk of imminent preterm birth where gestational age, imminent preterm birth, and risk of maternal infection can be assessed, and appropriate maternal/newborn care provided. However, coverage remains low in high-burden countries for reasons not previously systematically investigated.

Methods

The bottleneck analysis tool was applied in 12 countries in Africa and Asia as part of the Every Newborn Action Plan process. Country workshops involved technical experts to complete the survey tool, which is designed to synthesise and grade health system "bottlenecks", factors that hinder the scale up, of maternal-newborn intervention packages. We used quantitative and qualitative methods to analyse the bottleneck data, combined with literature review, to present priority bottlenecks and actions relevant to different health system building blocks for ACS.

Results

Eleven out of twelve countries provided data in response to the ACS questionnaire. Health system building blocks most frequently reported as having significant or very major bottlenecks were health information systems (11 countries), essential medical products and technologies (9 out of 11 countries) and health service delivery (9 out of 11 countries). Bottlenecks included absence of coverage data, poor gestational age metrics, lack of national essential medicines listing, discrepancies between prescribing authority and provider cadres managing care, delays due to referral, and lack of supervision, mentoring and quality improvement systems.

Conclusions

Analysis centred on health system building blocks in which 9 or more countries (>75%) reported very major or significant bottlenecks. Health information systems should include improved gestational age assessment and track ACS coverage, use and outcomes. Better health service delivery requires clarified policy assigning roles by level of care and cadre of provider, dependent on capability to assess gestational age and risk of preterm birth, and the implementation of guidelines with adequate supervision, mentoring and quality improvement systems, including audit and feedback. National essential medicines lists should include dexamethasone for antenatal use, and dexamethasone should be integrated into supply logistics.
  相似文献   
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