5,308 research outputs found

    In vivo manipulation of the extracellular matrix induces vascular regression in a basal chordate.

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    We investigated the physical role of the extracellular matrix (ECM) in vascular homeostasis in the basal chordate Botryllus schlosseri, which has a large, transparent, extracorporeal vascular network encompassing an area >100 cm2 We found that the collagen cross-linking enzyme lysyl oxidase is expressed in all vascular cells and that in vivo inhibition using β-aminopropionitrile (BAPN) caused a rapid, global regression of the entire network, with some vessels regressing >10 mm within 16 h. BAPN treatment changed the ultrastructure of collagen fibers in the vessel basement membrane, and the kinetics of regression were dose dependent. Pharmacological inhibition of both focal adhesion kinase (FAK) and Raf also induced regression, and levels of phosphorylated FAK in vascular cells decreased during BAPN treatment and FAK inhibition but not Raf inhibition, suggesting that physical changes in the vessel ECM are detected via canonical integrin signaling pathways. Regression is driven by apoptosis and extrusion of cells through the basal lamina, which are then engulfed by blood-borne phagocytes. Extrusion and regression occurred in a coordinated manner that maintained vessel integrity, with no loss of barrier function. This suggests the presence of regulatory mechanisms linking physical changes to a homeostatic, tissue-level response

    Knowledge Rich Natural Language Queries over Structured Biological Databases

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    Increasingly, keyword, natural language and NoSQL queries are being used for information retrieval from traditional as well as non-traditional databases such as web, document, image, GIS, legal, and health databases. While their popularity are undeniable for obvious reasons, their engineering is far from simple. In most part, semantics and intent preserving mapping of a well understood natural language query expressed over a structured database schema to a structured query language is still a difficult task, and research to tame the complexity is intense. In this paper, we propose a multi-level knowledge-based middleware to facilitate such mappings that separate the conceptual level from the physical level. We augment these multi-level abstractions with a concept reasoner and a query strategy engine to dynamically link arbitrary natural language querying to well defined structured queries. We demonstrate the feasibility of our approach by presenting a Datalog based prototype system, called BioSmart, that can compute responses to arbitrary natural language queries over arbitrary databases once a syntactic classification of the natural language query is made

    Reduction in unplanned hospitalizations associated with a physician focused intervention to reduce potentially inappropriate medication use among older adults: a population-based cohort study

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    BACKGROUND: A multimodal general practitioner-focused intervention in the Local Health Authority (LHA) of Parma, Italy, substantially reduced the prevalence of potentially inappropriate medication (PIM) use among older adults. Our objective was to estimate changes in hospitalization rates associated with the Parma LHA quality improvement initiative that reduced PIM use. METHODS: This population-based longitudinal cohort study was conducted among older residents ( \u3e 65 years) using the Parma LHA administrative healthcare database. Crude and adjusted unplanned hospitalization rates were estimated in 3 periods (pre-intervention: 2005-2008, intervention: 2009-2010, post-intervention: 2011-2014). Multivariable negative binomial models estimated trends in quarterly hospitalization rates among individuals at risk during each period using a piecewise linear spline for time, adjusted for time-dependent and time-fixed covariates. RESULTS: The pre-intervention, intervention, and post-intervention periods included 117,061, 107,347, and 121,871 older adults and had crude hospitalization rates of 146.2 (95% CI: 142.2-150.3), 146.8 (95% CI: 143.6-150.0), and 140.8 (95% CI: 136.9-144.7) per 1000 persons per year, respectively. The adjusted pre-intervention hospitalization rate was declining by 0.7% per quarter (IRR = 0.993; 95% CI: 0.991-0.995). The hospitalization rate declined more than twice as fast during the intervention period (1.8% per quarter, IRR = 0.982; 95% CI: 0.979-0.985) and was nearly constant post-intervention (IRR: 0.999; 95% CI: 0.997-1.001). Contrasting model predictions for the intervention period (Q1 2009 to Q4 2010), the intervention was associated with 1481 avoided hospitalizations. CONCLUSION: In a large population of older adults, a multimodal general practitioner-focused intervention to decrease PIM use was associated with a decline in the unplanned hospitalization rate. Such interventions to reduce high risk medication use among older adults warrant consideration by health systems seeking to improve health outcomes and reduce high-cost acute care utilization

    Tumour biology, metastatic sites and taxanes sensitivity as determinants of eribulin mesylate efficacy in breast cancer: results from the ERIBEX retrospective, international, multicenter study.

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    BACKGROUND: Our retrospective, international study aimed at evaluating the activity and safety of eribulin mesylate (EM) in pretreated metastatic breast cancer (MBC) in a routine clinical setting. METHODS: Patients treated with EM for a locally advanced or MBC between March 2011 and January 2014 were included in the study. Clinical and biological assessment of toxicity was performed at each visit. Tumour response was assessed every 3 cycles of treatment. A database was created to collect clinical, pathological and treatment data. RESULTS: Two hundred and fifty-eight patients were included in the study. Median age was 59 years old. Tumours were Hormone Receptor (HR)-positive (73.3 %) HER2-positive (10.2 %), and triple negative (TN, 22.5 %). 86.4 % of the patients presented with visceral metastases, mainly in the liver (67.4 %). Median previous metastatic chemotherapies number was 4 [1-9]. Previous treatments included anthracyclines and/or taxanes (100 %) and capecitabine (90.7 %). Median number of EM cycles was 5 [1-19]. The relative dose intensity was 0.917. At the time of analysis (median follow-up of 13.9 months), 42.3 % of the patients were still alive. The objective response rate was 25.2 % (95 %CI: 20-31) with a 36.1 % clinical benefit rate (CBR). Median time to progression (TTP) and overall survival were 3.97 (95 %CI: 3.25-4.3) and 11.2 (95 %CI: 9.3-12.1) months, respectively. One- and 2-year survival rates were 45.5 and 8.5 %, respectively. In multivariate analysis, HER2 positivity (HR = 0.29), the presence of lung metastases (HR = 2.49) and primary taxanes resistance (HR = 2.36) were the only three independent CBR predictive factors, while HR positivity (HR = 0.67), the presence of lung metastases (HR = 1.52) and primary taxanes resistance (HR = 1.50) were the only three TTP independent prognostic factors. Treatment was globally well tolerated. Most common grade 3-4 toxicities were neutropenia (20.9 %), peripheral neuropathy (3.9 %), anaemia (1.6 %), liver dysfunction (0.8 %) and thrombocytopenia (0.4 %). Thirteen patients (5 %) developed febrile neutropenia. CONCLUSION: EM is an effective new option in heavily pretreated MBC, with a favourable efficacy/safety ratio in a clinical practice setting. Our results comfort the use of this new molecule and pledge for the evaluation of EM-trastuzumab combination in this setting. Tumour biology, primary taxanes sensitivity and metastatic sites could represent useful predictive and prognostic factors

    Genomic diversity affects the accuracy of bacterial single-nucleotide polymorphism-calling pipelines

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    Background: Accurately identifying SNPs from bacterial sequencing data is an essential requirement for using genomics to track transmission and predict important phenotypes such as antimicrobial resistance. However, most previous performance evaluations of SNP calling have been restricted to eukaryotic (human) data. Additionally, bacterial SNP calling requires choosing an appropriate reference genome to align reads to, which, together with the bioinformatic pipeline, affects the accuracy and completeness of a set of SNP calls obtained. This study evaluates the performance of 209 SNP calling pipelines using a combination of simulated data from 254 strains of 10 clinically common bacteria and real data from environmentally-sourced and genomically diverse isolates within the genera Citrobacter, Enterobacter, Escherichia and Klebsiella. Results: We evaluated the performance of 209 SNP calling pipelines, aligning reads to genomes of the same or a divergent strain. Irrespective of pipeline, a principal determinant of reliable SNP calling was reference genome selection. Across multiple taxa, there was a strong inverse relationship between pipeline sensitivity and precision, and the Mash distance (a proxy for average nucleotide divergence) between reads and reference genome. The effect was especially pronounced for diverse, recombinogenic, bacteria such as Escherichia coli, but less dominant for clonal species such as Mycobacterium tuberculosis. Conclusions: The accuracy of SNP calling for a given species is compromised by increasing intra-species diversity. When reads were aligned to the same genome from which they were sequenced, among the highest performing pipelines was Novoalign/GATK. By contrast, when reads were aligned to particularly divergent genomes, the highest-performing pipelines often employed the aligners NextGenMap or SMALT, and/or the variant callers LoFreq, mpileup or Strelka

    Attitudes toward mixed methods research in psychology: the best of both worlds?

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    In psychology, there has been a growing interest in mixed methods approaches, however, only a minority of published research explicitly use this methodology. This study aimed to explore the full range of attitudes toward mixed methods research in psychology held by students and academics, using the model of attitudes by Eagly and Chaiken as a framework. Fourteen psychology students and seven academics (48% male and 52% female with ages ranging from 19- to 64-years old) were interviewed about their attitudes toward mixed methods research. Interviews were transcribed and analyzed using thematic analysis. Findings indicate that while participants were generally open to the methodology, misunderstandings were common, most felt they lacked the skills and experience necessary to conduct this research and many were sceptical of mixed methods researchers’ motivations and practices. Identifying attitudes toward mixed methods research has the potential to dispel myths, promote attitudinal change, and increase both the use and teaching of this approach in psychology

    A functional-cognitive framework for attitude research

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    In attitude research, behaviours are often used as proxies for attitudes and attitudinal processes. This practice is problematic because it conflates the behaviours that need to be explained (explanandum) with the mental constructs that are used to explain these behaviours (explanans). In the current chapter we propose a meta-theoretical framework that resolves this problem by distinguishing between two levels of analysis. According to the proposed framework, attitude research can be conceptualised as the scientific study of evaluation. Evaluation is defined not in terms of mental constructs but in terms of elements in the environment, more specifically, as the effect of stimuli on evaluative responses. From this perspective, attitude research provides answers to two questions: (1) Which elements in the environment moderate evaluation? (2) What mental processes and representations mediate evaluation? Research on the first question provides explanations of evaluative responses in terms of elements in the environment (functional level of analysis); research on the second question offers explanations of evaluation in terms of mental processes and representations (cognitive level of analysis). These two levels of analysis are mutually supportive, in that better explanations at one level lead to better explanations at the other level. However, their mutually supportive relation requires a clear distinction between the concepts of their explanans and explanandum, which are conflated if behaviours are treated as proxies for mental constructs. The value of this functional-cognitive framework is illustrated by applying it to four central questions of attitude research

    Did a physician-targeted intervention that reduced potentially inappropriate prescribing to elderly patients also reduce related hospitalizations?

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    Objectives: To determine whether a general practitioner focused intervention aimed at decreasing PIM prescribing in the elderly can decrease the risk of PIM-related hospitalizations. Poster presented at 2016 ISPOR conference in Washington DC.https://jdc.jefferson.edu/jcphposters/1005/thumbnail.jp

    Hadron beam test of a scintillating fibre tracker system for elastic scattering and luminosity measurement in ATLAS

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    A scintillating fibre tracker is proposed to measure elastic proton scattering at very small angles in the ATLAS experiment at CERN. The tracker will be located in so-called Roman Pot units at a distance of 240 m on each side of the ATLAS interaction point. An initial validation of the design choices was achieved in a beam test at DESY in a relatively low energy electron beam and using slow off-the-shelf electronics. Here we report on the results from a second beam test experiment carried out at CERN, where new detector prototypes were tested in a high energy hadron beam, using the first version of the custom designed front-end electronics. The results show an adequate tracking performance under conditions which are similar to the situation at the LHC. In addition, the alignment method using so-called overlap detectors was studied and shown to have the expected precision.Comment: 12 pages, 8 figures. Submitted to Journal of Instrumentation (JINST
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