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EUS-guided portal pressure gradient measurement with a simple novel device: a human pilot study.
Background and aimsPortal hypertension is a serious adverse event of liver cirrhosis. Recently, we developed a simple novel technique for EUS-guided portal pressure gradient (PPG) measurement (PPGM). Our animal studies showed excellent correlation between EUS-PPGM and interventional radiology-acquired PPGM. In this video we demonstrate the results of the first human pilot study of EUS-PPGM in patients with liver disease.MethodsEUS-PPGM was performed by experienced endosonographers using a linear echoendoscope, a 25-gauge FNA needle, and a novel compact manometer. The portal vein and hepatic vein (or inferior vena cava) were targeted by use of a transgastric or transduodenal approach. Feasibility was defined as successful PPGM in each patient. Safety was based on adverse events captured in a postprocedural interview.ResultsTwenty-eight patients underwent EUS-PPGM with 100% technical success and no adverse events. PPG ranged from 1.5 to 19 mm Hg and had excellent correlation with clinical parameters of portal hypertension, including the presence of varices (P = .0002), PH gastropathy (P = .007), and thrombocytopenia (P = .036).ConclusionThis novel technique of EUS-PPGM using a 25-gauge needle and compact manometer is feasible and appears safe. Given the availability of EUS and the simplicity of the manometry setup, EUS-guided PPG may represent a promising breakthrough for procuring indispensable information in the management of patients with liver disease
Computer animation data management: Review of evolution phases and emerging issues
The computer animation industry has been booming and prospering in recent thirty years. One of the significant changes faced by this industry is the evolution of computer-animation data and, yet, extant literature has offered very little insights into the evolution process and management issues pertinent to computer-animation data. Hence, many questions have surfaced in the extant literature of computer-animation data management. For example, to what extent has the data content expanded in terms of quantity and quality? To what extent has the information technology used to store and process the data changed? To what extent have the user and the community groups diversified in terms of their nature and number? Knowledge pertaining to these issues can provide new research directions to academics and also insights to practitioners for more effective and innovative management of computer-animation data. This conceptual paper, therefore, takes the pioneering step to address these issues by proposing four factors prudent for examining the evolution phases associated with computer-animation data management: technology, content, users, and community. Next, this paper presents a conceptual framework illustrating the inter-dependent relationships between these four factors together with associated theoretical and managerial issues. This paper, albeit limited by its conceptual nature, advances the extant literature of computer animation, information system, and open-product model
Single-cell epigenomic variability reveals functional cancer heterogeneity.
BackgroundCell-to-cell heterogeneity is a major driver of cancer evolution, progression, and emergence of drug resistance. Epigenomic variation at the single-cell level can rapidly create cancer heterogeneity but is difficult to detect and assess functionally.ResultsWe develop a strategy to bridge the gap between measurement and function in single-cell epigenomics. Using single-cell chromatin accessibility and RNA-seq data in K562 leukemic cells, we identify the cell surface marker CD24 as co-varying with chromatin accessibility changes linked to GATA transcription factors in single cells. Fluorescence-activated cell sorting of CD24 high versus low cells prospectively isolated GATA1 and GATA2 high versus low cells. GATA high versus low cells express differential gene regulatory networks, differential sensitivity to the drug imatinib mesylate, and differential self-renewal capacity. Lineage tracing experiments show that GATA/CD24hi cells have the capability to rapidly reconstitute the heterogeneity within the entire starting population, suggesting that GATA expression levels drive a phenotypically relevant source of epigenomic plasticity.ConclusionSingle-cell chromatin accessibility can guide prospective characterization of cancer heterogeneity. Epigenomic subpopulations in cancer impact drug sensitivity and the clonal dynamics of cancer evolution
Precise Environmental Searches: Integrating Hierarchical Information Search with EnviroDaemon
Information retrieval has evolved from searches of references, to abstracts, to documents. Search on the Web involves search engines that promise to parse full-text and other files: audio, video, and multimedia. With the indexable Web at 320 million pages and growing, difficulties with locating relevant information have become apparent. The most prevalent means for information retrieval relies on syntax-based methods: keywords or strings of characters are presented to a search engine, and it returns all the matches in the available documents. This method is satisfactory and easy to implement, but it has some inherent limitations that make it unsuitable for many tasks. Instead of looking for syntactical patterns, the user often is interested in keyword meaning or the location of a particular word in a title or header. This paper describes some precise search approaches in the environmental domain that locate information according to syntactic criteria, augmented by the utilization of information in a certain context. The main emphasis of this paper lies in the treatment of structured knowledge, where essential aspects about the topic of interest are encoded not only by the individual items, but also by their relationships among each other. Examples for such structured knowledge are hypertext documents, diagrams, logical and chemical formulae. Benefits of this approach are enhanced precision and approximate search in an already focused, context-specific search engine for the environment: EnviroDaemon
Catastro de poblaciones de insectos en siembras de Capsicum chinense L. en Georgetown, San Vicente, usando trampas CC modificadas.
The insect populations in hot pepper, Capsicum chinense L. (Solanaceae), were surveyed in Georgetown, St. Vincent, during the 2004 wet and 2005 dry seasons. Modified white, blue, and yellow CC traps were used to capture insects in the plantings. Overall, 69 insect families were captured, 41 of which were captured during both the wet and dry seasons. During the wet season, the greatest numbers of individuals captured were from the Cecidomyiidae, Chironomidae, Chloropidae, Chrysomelidae, Cicadellidae, and Drosophilidae families. During the dry season, the greatest numbers of individuals captured were from Chrysomelidae and Cicadellidae families. The addition of dichlorvos as a killing agent and propylene glycol as an insect preservative to the CC traps increased the number and diversity of insects caught. Additionally, propylene glycol helped to preserve the specimens for taxonomic and genetic determinations. CC traps with yellow bases attracted more insect families than traps with white or blue bases. However, CC traps with blue bases caught more Lonchaeidae during both the wet and dry seasons, and more Tachinidae during the dry season. CC traps with white or yellow trap bases were equally attractive to insects in the families Aleyrodidae, Drosophilidae, Lauxaniidae, and Otitidae.Las poblaciones de insectos en el ajĂ picante, Capsicum chinense L., se monitorearon en Georgetown, San Vicente, durante la Ă©poca de lluvia de 2004 y la de sequĂa de 2005. Se usaron las trampas CC modificadas, blancas, azules y amarillas, para capturar insectos en las siembras. Se capturaron 69 familias de insectos; 41 de Ă©stas se capturaron durante ambas Ă©pocas, la de lluvia y la de sequĂa. Durante la Ă©poca de lluvia, el mayor nĂşmero de individuos capturados pertenecĂa a las familias Cecidomyiidae, Chironomidae, Chloropidae, Chrysomelidae, Cicadellidae y Drosophilidae. Durante la Ă©poca de sequĂa, el mayor nĂşmero de individuos capturados pertenecĂa a las familias Cicadellidae y Chrysomelidae. El nĂşmero y la diversidad de los insectos capturados aumentaron al añadir dichlorvos como un agente exterminador y glicol de propileno como agente preservativo a las trampas CC. Además, el glicol de propileno ayudĂł a preservar los especĂmenes para las determinaciones taxonĂłmicas y genĂ©ticas. Las trampas CC con bases amarillas atrajeron más familias de insectos que las trampas con bases blancas o azules. Sin embargo, las trampas CC con bases azules capturaron más Lonchaeidae durante ambas Ă©pocas, de lluvia y sequĂa, y más Tachinidae durante la Ă©poca de sequĂa. Las trampas CC con bases blancas o amarillas resultaron igualmente atractivas a los insectos en las familias Aleyrodidae, Drosophilidae, Lauxaniidae y Otitidae
Investigating the functionality of an OCT4-short response element in human induced pluripotent stem cells.
Pluripotent stem cells offer great therapeutic promise for personalized treatment platforms for numerous injuries, disorders, and diseases. Octamer-binding transcription factor 4 (OCT4) is a key regulatory gene maintaining pluripotency and self-renewal of mammalian cells. With site-specific integration for gene correction in cellular therapeutics, use of the OCT4 promoter may have advantages when expressing a suicide gene if pluripotency remains. However, the human OCT4 promoter region is 4 kb in size, limiting the capacity of therapeutic genes and other regulatory components for viral vectors, and decreasing the efficiency of homologous recombination. The purpose of this investigation was to characterize the functionality of a novel 967bp OCT4-short response element during pluripotency and to examine the OCT4 titer-dependent response during differentiation to human derivatives not expressing OCT4. Our findings demonstrate that the OCT4-short response element is active in pluripotency and this activity is in high correlation with transgene expression in vitro, and the OCT4-short response element is inactivated when pluripotent cells differentiate. These studies demonstrate that this shortened OCT4 regulatory element is functional and may be useful as part of an optimized safety component in a site-specific gene transferring system that could be used as an efficient and clinically applicable safety platform for gene transfer in cellular therapeutics
Selective-Area Growth of Heavily \u3cem\u3en\u3c/em\u3e–Doped GaAs Nanostubs on Si(001) by Molecular Beam Epitaxy
Using an aspect ratio trapping technique, we demonstrate molecular beam epitaxy of GaAs nanostubs on Si(001) substrates. Nanoholes in a SiO2 mask act as a template for GaAs-on-Si selective-area growth(SAG) of nanostubs 120 nm tall and ≤100 nm in diameter. We investigate the influence of growthparameters including substrate temperature and growth rate on SAG. Optimizing these parameters results in complete selectivity with GaAsgrowth only on the exposed Si(001). Due to the confined-geometry, strain and defects in the GaAs nanostubs are restricted in lateral dimensions, and surface energy is further minimized. We assess the electrical properties of the selectively grownGaAs nanostubs by fabricating heterogeneous p+–Si/n+–GaAs p–n diodes
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