736 research outputs found

    Approximate Semantic Matching Over Linked Data Streams

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    In the Internet of Things (IoT),data can be generated by all kinds of smart things. In such context, enabling machines to process and understand such data is critical. Semantic Web technologies, such as Linked Data, provide an effective and machine-understandable way to represent IoT data for further processing. It is a challenging issue to match Linked Data streams semantically based on text similarity as text similarity computation is time consuming. In this paper, we present a hashing-based approximate approach to efficiently match Linked Data streams with users’ needs. We use the Resource Description Framework (RDF) to represent IoT data and adopt triple patterns as user queries to describe users’ data needs. We then apply locality-sensitive hashing techniques to transform semantic data into numerical values to support efficient matching between data and user queries. We design a modified k nearest neighbors (kNN) algorithm to speedup the matching process. The experimental results show that our approach is up to five times faster than the traditional methods and can achieve high precisions and recalls

    The Structure of an RNAi Polymerase Links RNA Silencing and Transcription

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    RNA silencing refers to a group of RNA-induced gene-silencing mechanisms that developed early in the eukaryotic lineage, probably for defence against pathogens and regulation of gene expression. In plants, protozoa, fungi, and nematodes, but apparently not insects and vertebrates, it involves a cell-encoded RNA-dependent RNA polymerase (cRdRP) that produces double-stranded RNA triggers from aberrant single-stranded RNA. We report the 2.3-Å resolution crystal structure of QDE-1, a cRdRP from Neurospora crassa, and find that it forms a relatively compact dimeric molecule, each subunit of which comprises several domains with, at its core, a catalytic apparatus and protein fold strikingly similar to the catalytic core of the DNA-dependent RNA polymerases responsible for transcription. This evolutionary link between the two enzyme types suggests that aspects of RNA silencing in some organisms may recapitulate transcription/replication pathways functioning in the ancient RNA-based world

    Olkiluoto Biosphere Description 2009

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    High-throughput identification of genotype-specific cancer vulnerabilities in mixtures of barcoded tumor cell lines.

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    Hundreds of genetically characterized cell lines are available for the discovery of genotype-specific cancer vulnerabilities. However, screening large numbers of compounds against large numbers of cell lines is currently impractical, and such experiments are often difficult to control. Here we report a method called PRISM that allows pooled screening of mixtures of cancer cell lines by labeling each cell line with 24-nucleotide barcodes. PRISM revealed the expected patterns of cell killing seen in conventional (unpooled) assays. In a screen of 102 cell lines across 8,400 compounds, PRISM led to the identification of BRD-7880 as a potent and highly specific inhibitor of aurora kinases B and C. Cell line pools also efficiently formed tumors as xenografts, and PRISM recapitulated the expected pattern of erlotinib sensitivity in vivo

    Insights into the pre-initiation events of bacteriophage phi6 RNA-dependent RNA polymerase : towards the assembly of a productive binary complex

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    The RNA-dependent RNA polymerase (RdRP) of double-stranded RNA (dsRNA) viruses performs both RNA replication and transcription. In order to initiate RNA polymerization, viral RdRPs must be able to interact with the incoming 3 terminus of the template and position it, so that a productive binary complex is formed. Structural studies have revealed that RdRPs of dsRNA viruses that lack helicases have electrostatically charged areas on the polymerase surface, which might facilitate such interactions. In this study, structure-based mutagenesis, enzymatic assays and molecular mapping of bacteriophage 6 RdRP and its RNA were used to elucidate the roles of the negatively charged plough area on the polymerase surface, of the rim of the template tunnel and of the template specificity pocket that is key in the formation of the productive RNA-polymerase binary complex. The positively charged rim of the template tunnel has a significant role in the engagement of highly structured ssRNA molecules, whereas specific interactions further down in the template tunnel promote ssRNA entry to the catalytic site. Hence, we show that by aiding the formation of a stable binary complex with optimized RNA templates, the overall polymerization activity of the 6 RdRP can be greatly enhanced.The RNA-dependent RNA polymerase (RdRP) of double-stranded RNA (dsRNA) viruses performs both RNA replication and transcription. In order to initiate RNA polymerization, viral RdRPs must be able to interact with the incoming 3 terminus of the template and position it, so that a productive binary complex is formed. Structural studies have revealed that RdRPs of dsRNA viruses that lack helicases have electrostatically charged areas on the polymerase surface, which might facilitate such interactions. In this study, structure-based mutagenesis, enzymatic assays and molecular mapping of bacteriophage 6 RdRP and its RNA were used to elucidate the roles of the negatively charged plough area on the polymerase surface, of the rim of the template tunnel and of the template specificity pocket that is key in the formation of the productive RNA-polymerase binary complex. The positively charged rim of the template tunnel has a significant role in the engagement of highly structured ssRNA molecules, whereas specific interactions further down in the template tunnel promote ssRNA entry to the catalytic site. Hence, we show that by aiding the formation of a stable binary complex with optimized RNA templates, the overall polymerization activity of the 6 RdRP can be greatly enhanced.The RNA-dependent RNA polymerase (RdRP) of double-stranded RNA (dsRNA) viruses performs both RNA replication and transcription. In order to initiate RNA polymerization, viral RdRPs must be able to interact with the incoming 3 terminus of the template and position it, so that a productive binary complex is formed. Structural studies have revealed that RdRPs of dsRNA viruses that lack helicases have electrostatically charged areas on the polymerase surface, which might facilitate such interactions. In this study, structure-based mutagenesis, enzymatic assays and molecular mapping of bacteriophage 6 RdRP and its RNA were used to elucidate the roles of the negatively charged plough area on the polymerase surface, of the rim of the template tunnel and of the template specificity pocket that is key in the formation of the productive RNA-polymerase binary complex. The positively charged rim of the template tunnel has a significant role in the engagement of highly structured ssRNA molecules, whereas specific interactions further down in the template tunnel promote ssRNA entry to the catalytic site. Hence, we show that by aiding the formation of a stable binary complex with optimized RNA templates, the overall polymerization activity of the 6 RdRP can be greatly enhanced.Peer reviewe

    Waiting times for radiotherapy: variation over time and between cancer networks in southeast England

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    The aim of this study was to investigate variations in the length of time that patients with cancer wait from diagnosis to treatment with radiotherapy. A total of 57 426 men and 71 018 women diagnosed with cancer between 1992 and 2001 and receiving radiotherapy within 6 months of diagnosis were identified from the Thames Cancer Registry database. In total, 12 sites were identified for which a substantial number or proportion of patients received radiotherapy: head and neck, oesophagus, colon, rectum, lung, nonmelanoma skin cancer, breast, uterus, prostate, bladder, brain and non-Hodgkin's lymphoma. Median waiting times from diagnosis to radiotherapy were calculated, together with the proportion of patients who received radiotherapy within 60 days of diagnosis, and analysed by year of diagnosis, cancer site, deprivation quintile, age at diagnosis, sex and cancer network of either residence or treatment. Logistic regression was used to adjust the proportion receiving treatment within 60 days for the effects of the other factors. There were significant differences in the proportions receiving radiotherapy within 60 days between different networks and different cancer sites, which remained after adjustment. Median waiting times varied from 42 to 65 days across networks of residence, with the adjusted proportion treated within 60 days ranging from 44 to 71%. There was no difference between male and female patients after adjustment for the other factors, particularly site. There was a highly significant trend over time: the median wait increased from 45 days in 1992 to 76 days in 2001, while the adjusted proportion being treated within 60 days declined by almost a half, from 64 to 35%, over the same period

    Functional expression of NF1 tumor suppressor protein: association with keratin intermediate filaments during the early development of human epidermis

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    BACKGROUND: NF1 refers to type 1 neurofibromatosis syndrome, which has been linked with mutations of the large NF1 gene. NF1 tumor suppressor protein, neurofibromin, has been shown to regulate ras: the NF1 protein contains a GTPase activating protein (GAP) related domain which functions as p21rasGAP. Our studies have previously demonstrated that the NF1 protein forms a high affinity association with cytokeratin 14 during the formation of desmosomes and hemidesmosomes in cultured keratinocytes. METHODS: The expression of NF1 protein was studied in developing human epidermis using western transfer analysis, indirect immunofluorescence, confocal laser scanning microscopy, immunoelectron microscopy, and in situ hybridization. RESULTS: The expression of NF1 protein was noted to be highly elevated in the periderm at 8 weeks estimated gestational age (EGA) and in the basal cells at 8–14 weeks EGA. During this period, NF1 protein was associated with cytokeratin filaments terminating to desmosomes and hemidesmosomes. NF1 protein did not display colocalization with α-tubulin or actin of the cytoskeleton, or with adherens junction proteins. CONCLUSIONS: These results depict an early fetal period when the NF1 tumor suppressor is abundantly expressed in epidermis and associated with cytokeratin filaments. This period is characterized by the initiation of differentiation of the basal cells, maturation of the basement membrane zone as well as accentuated formation of selected cellular junctions. NF1 tumor suppressor may function in the regulation of epidermal histogenesis via controlling the organization of the keratin cytoskeleton during the assembly of desmosomes and hemidesmosomes

    Dementia Wristband Report

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    This research project explored the use of new wearable and mobile technologies to support independent living and social interactions in the community for people living with dementia and their carers, more safely and for longer. The three key aims of the project were to: • Assess the potential acceptability, and usability of a mobile phone App and wearable wristband solution • Test the use of the technological in the everyday life contexts • Evaluate the usability and utility of a mobile phone App and digital wristband to reduce social isolation and improve health outcomes The research project had two stages: Stage 1 - Acceptability, utility and usability of the devices This stage of the project focused on developing initial understandings of the ways in which the proposed technological solutions work and potentially meet the needs of people living with dementia and their carers. This was achieved through: - Technology testing by the project team members. This gave the team a better understanding of the device used in the project. - Interviews with people with dementia and their carers, and with health and social care professionals. The interviews explored whether participants were receptive to, and what they thought about, the proposed solutions. Any concerns they had about the tracking technology in general or about the technology used in the project were also examined. Stage 2: Real world testing of the wristbands and smartphone App Research participant’s trialled the technology, as part of their everyday lives, for up to three months. During this period the research team worked closely with them to provide training and technological support and used a multi-method data collection focused on semi-structured interviews and observation to capture their experiences of using the technology. The participants living with dementia and their carers were given the opportunity to choose the technology that best suits them, either a wristbands or a smartphone application. Key findings In summary, through the interviews and focus groups and real world technology testing the research team and SME partners found there are issues around: - the use of technology for people living with dementia and their carers – for some people it was seen as a real benefit, others did not want to engage with the technology or have others know where they were. - education, information and support for people living with dementia and their carers to use new technologies; even when delivered via familiar technologies this can be challenging and needs support and time - support for family/other carers who are key to the support of mobile and wearable technologies. - support for people who do not have a local or remote family carer who can support the use of new technologies needs to be considered. - current GPS technologies not being accurate as a stand alone way of finding someone who may be lost or needing support. - safeguarding – which needs to take an holistic approach and include more traditional and ‘paper based’ safeguarding systems such as the Herbert protocol, - emerging and new technologies, which are developing constantly but a national approach is still missing; - the challenges for unpaid carers and people living with dementia to around exploring options around new technologies and deciding what are the best/cost effective options for their situations. - wearable and mobile technologies which can support people to be more independent in the community, but the technologies need to be: introduced early; affordable and be more easily supported by family and professional care givers as appropriate

    A nationwide real-world study on dynamic ustekinumab dosing and concomitant medication use among Crohn's disease patients in Finland

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    Background Real-world evidence to support optimal ustekinumab dosing for refractory Crohn's disease (CD) patients remains limited. Data from a retrospective nationwide chart review study was utilized to explore ustekinumab dosing dynamics and optimization, identify possible clinical predictors of dose intensification, and to evaluate ustekinumab trough concentrations (TCs) and concomitant medication use in Finland. Methods Information gathered from17 Finnish hospitals included clinical chart data from 155 adult CD patients who received intravenous ustekinumab induction during 2017-2018. Data on ustekinumab dosing and TCs, concomitant corticosteroid and immunosuppressant use, and antiustekinumab antibodies were analyzed in a two-year follow-up, subject to availability. Results Among 140 patients onustekinumab maintenance therapy, dose optimization was required in 55(39%) of the patients, and 41/47 dose-intensified patients (87%) persisted on ustekinumab. At baseline, dose-intensified patient group had significantly higher C-reactive protein (CRP) levels, and at week 16, significantly lower ustekinumab TCs than in patients without dose intensification. Irrespective of dose optimization, a statistically significant reduction in the use of corticosteroids was observed at both 16 weeks and one year, coupled with an increased proportion of patients on ustekinumab monotherapy. Antiustekinumab antibodies were undetectable in all 28 samples from 25 patients collected throughout the study period. Conclusions Nearly a third of all CD patients on ustekinumab maintenance therapy, with a history of treatment-refractory and long-standing disease, required dose intensification. These patients persisted on ustekinumab and had significant reduction of corticosteroid use. Increased baseline CRP was identified as the sole indicator of dose intensification.Peer reviewe
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