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1.
Drug development from natural sources is an important and fast developing area. Natural sources (plants) have been used to cure a range of diseases for Thousands of years. Different online medicinal plant databases provide information about classifications, activities, phytochemicals and structure of phytochemicals in different formats. These databases do not cover all aspects of medicinal plants. MAPS (Medicinal plant Activities, Phytochemicals & structural database) has been constructed with uniqueness that it combines all information in one web resource and additionally provides test targets on which particular plant found to be effective with reference to the original paper as well. MAPS database is user friendly information resource, including the data of > 500 medicinal plants. This database includes phytochemical constituents, their structure in mol format, different activities possessed by the medicinal plant with the targets reported in literature.

Availability

http://www.mapsdatabase.com  相似文献   

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The human Y chromosome is the sex determining chromosome. The number of proteins associated with this chromosome is 196 and 107 of the 196 proteins have yet not been characterised. Here, we describe the analysis of these 107 proteins by computing various physicochemical properties using sequence and predicted structural data to elucidate molecular function. We present the derived data in the form a form a database made freely available for download, review, refinement and update.

Availability

http://puratham.googlepages.com/ or http://puratham.googlepages.com/ftpconnection  相似文献   

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A common practice in computational genomic analysis is to use a set of ‘background’ sequences as negative controls for evaluating the false-positive rates of prediction tools, such as gene identification programs and algorithms for detection of cis-regulatory elements. Such ‘background’ sequences are generally taken from regions of the genome presumed to be intergenic, or generated synthetically by ‘shuffling’ real sequences. This last method can lead to underestimation of false-positive rates. We developed a new method for generating artificial sequences that are modeled after real intergenic sequences in terms of composition, complexity and interspersed repeat content. These artificial sequences can serve as an inexhaustible source of high-quality negative controls. We used artificial sequences to evaluate the false-positive rates of a set of programs for detecting interspersed repeats, ab initio prediction of coding genes, transcribed regions and non-coding genes. We found that RepeatMasker is more accurate than PClouds, Augustus has the lowest false-positive rate of the coding gene prediction programs tested, and Infernal has a low false-positive rate for non-coding gene detection. A web service, source code and the models for human and many other species are freely available at http://repeatmasker.org/garlic/.  相似文献   

6.
Studies describing intricate patterns of DNA methylation in nematode and ciliate are controversial due to the uncertainty of genomic evolutionary conservation of DNA methylation enzymes.See related research articles http://genomebiology.com/2012/13/10/R99 and http://genomebiology.com/2012/13/10/R100  相似文献   

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8.

Background

Understanding living systems is crucial for curing diseases. To achieve this task we have to understand biological networks based on protein-protein interactions. Bioinformatics has come up with a great amount of databases and tools that support analysts in exploring protein-protein interactions on an integrated level for knowledge discovery. They provide predictions and correlations, indicate possibilities for future experimental research and fill the gaps to complete the picture of biochemical processes. There are numerous and huge databases of protein-protein interactions used to gain insights into answering some of the many questions of systems biology. Many computational resources integrate interaction data with additional information on molecular background. However, the vast number of diverse Bioinformatics resources poses an obstacle to the goal of understanding. We present a survey of databases that enable the visual analysis of protein networks.

Results

We selected M =10 out of N =53 resources supporting visualization, and we tested against the following set of criteria: interoperability, data integration, quantity of possible interactions, data visualization quality and data coverage. The study reveals differences in usability, visualization features and quality as well as the quantity of interactions. StringDB is the recommended first choice. CPDB presents a comprehensive dataset and IntAct lets the user change the network layout. A comprehensive comparison table is available via web. The supplementary table can be accessed on http://tinyurl.com/PPI-DB-Comparison-2015.

Conclusions

Only some web resources featuring graph visualization can be successfully applied to interactive visual analysis of protein-protein interaction. Study results underline the necessity for further enhancements of visualization integration in biochemical analysis tools. Identified challenges are data comprehensiveness, confidence, interactive feature and visualization maturing.  相似文献   

9.

Background

Identification of DNA/Protein motifs is a crucial problem for biologists. Computational techniques could be of great help in this identification. In this direction, many computational models for motifs have been proposed in the literature.

Methods

One such important model is the motif model. In this paper we describe a motif search web tool that predominantly employs this motif model. This web tool exploits the state-of-the art algorithms for solving the motif search problem.

Results

The online tool has been helping scientists identify many unknown motifs. Many of our predictions have been successfully verified as well. We hope that this paper will expose this crucial tool to many more scientists.

Availability and requirements

Project name: PMS - Panoptic Motif Search Tool. Project home page: http://pms.engr.uconn.edu or http://motifsearch.com. Licence: PMS tools will be readily available to any scientist wishing to use it for non-commercial purposes, without restrictions. The online tool is freely available without login.  相似文献   

10.
Fruit Crops Diseases Database (FCDD) requires a number of biotechnology and bioinformatics tools. The FCDD is a unique bioinformatics resource that compiles information about 162 details on fruit crops diseases, diseases type, its causal organism, images, symptoms and their control. The FCDD contains 171 phytochemicals from 25 fruits, their 2D images and their 20 possible sequences. This information has been manually extracted and manually verified from numerous sources, including other electronic databases, textbooks and scientific journals. FCDD is fully searchable and supports extensive text search. The main focus of the FCDD is on providing possible information of fruit crops diseases, which will help in discovery of potential drugs from one of the common bioresource-fruits. The database was developed using MySQL. The database interface is developed in PHP, HTML and JAVA. FCDD is freely available.

Availability

http://www.fruitcropsdd.com/  相似文献   

11.
While a huge amount of information about biological literature can be obtained by searching the PubMed database, reading through all the titles and abstracts resulting from such a search for useful information is inefficient. Text mining makes it possible to increase this efficiency. Some websites use text mining to gather information from the PubMed database; however, they are database-oriented, using pre-defined search keywords while lacking a query interface for user-defined search inputs. We present the PubMed Abstract Reading Helper (PubstractHelper) website which combines text mining and reading assistance for an efficient PubMed search. PubstractHelper can accept a maximum of ten groups of keywords, within each group containing up to ten keywords. The principle behind the text-mining function of PubstractHelper is that keywords contained in the same sentence are likely to be related. PubstractHelper highlights sentences with co-occurring keywords in different colors. The user can download the PMID and the abstracts with color markings to be reviewed later. The PubstractHelper website can help users to identify relevant publications based on the presence of related keywords, which should be a handy tool for their research.

Availability

http://bio.yungyun.com.tw/ATM/PubstractHelper.aspx and http://holab.med.ncku.edu.tw/ATM/PubstractHelper.aspx  相似文献   

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13.

Background

Semantic Web has established itself as a framework for using and sharing data across applications and database boundaries. Here, we present a web-based platform for querying biological Semantic Web databases in a graphical way.

Results

SPARQLGraph offers an intuitive drag & drop query builder, which converts the visual graph into a query and executes it on a public endpoint. The tool integrates several publicly available Semantic Web databases, including the databases of the just recently released EBI RDF platform. Furthermore, it provides several predefined template queries for answering biological questions. Users can easily create and save new query graphs, which can also be shared with other researchers.

Conclusions

This new graphical way of creating queries for biological Semantic Web databases considerably facilitates usability as it removes the requirement of knowing specific query languages and database structures. The system is freely available at http://sparqlgraph.i-med.ac.at.  相似文献   

14.

Objective

To investigate the effectiveness of educational poster on improving secondary school students'' knowledge of emergency management of dental trauma.

Methods

A cluster randomised controlled trial was conducted. 16 schools with total 671 secondary students who can read Chinese or English were randomised into intervention (poster, 8 schools, 364 students) and control groups (8 schools, 305 students) at the school level. Baseline knowledge of dental trauma was obtained by a questionnaire. Poster containing information of dental trauma management was displayed in a classroom for 2 weeks in each school in the intervention group whereas in the control group there was no display of such posters. Students of both groups completed the same questionnarie after 2 weeks.

Results

Two-week display of posters improved the knowledge score by 1.25 (p-value = 0.0407) on average.

Conclusion

Educational poster on dental trauma management significantly improved the level of knowledge of secondary school students in Hong Kong.

Trial Registration

HKClinicalTrial.com HKCTR-1343 ClinicalTrials.gov NCT01809457  相似文献   

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DNA methylation is a chemical modification of cytosine bases that is pivotal for gene regulation, cellular specification and cancer development. Here, we describe an R package, methylKit, that rapidly analyzes genome-wide cytosine epigenetic profiles from high-throughput methylation and hydroxymethylation sequencing experiments. methylKit includes functions for clustering, sample quality visualization, differential methylation analysis and annotation features, thus automating and simplifying many of the steps for discerning statistically significant bases or regions of DNA methylation. Finally, we demonstrate methylKit on breast cancer data, in which we find statistically significant regions of differential methylation and stratify tumor subtypes. methylKit is available at http://code.google.com/p/methylkit.  相似文献   

17.

Background

Dynamic visual exploration of detailed pathway information can help researchers digest and interpret complex mechanisms and genomic datasets.

Results

ChiBE is a free, open-source software tool for visualizing, querying, and analyzing human biological pathways in BioPAX format. The recently released version 2 can search for neighborhoods, paths between molecules, and common regulators/targets of molecules, on large integrated cellular networks in the Pathway Commons database as well as in local BioPAX models. Resulting networks can be automatically laid out for visualization using a graphically rich, process-centric notation. Profiling data from the cBioPortal for Cancer Genomics and expression data from the Gene Expression Omnibus can be overlaid on these networks.

Conclusions

ChiBE’s new capabilities are organized around a genomics-oriented workflow and offer a unique comprehensive pathway analysis solution for genomics researchers. The software is freely available at http://code.google.com/p/chibe.  相似文献   

18.
The polarization of post-mitotic neurons is poorly understood. Preexisting spatially asymmetric cues, distributed within the neuron or as extracellular gradients, could be required for neurons to polarize. Alternatively, neurons might have the intrinsic ability to polarize without any preestablished asymmetric cues. In Caenorhabditis elegans, the UNC-40 (DCC) receptor mediates responses to the extracellular UNC-6 (netrin) guidance cue. For the HSN neuron, an UNC-6 ventral-dorsal gradient asymmetrically localizes UNC-40 to the ventral HSN surface. There an axon forms, which is ventrally directed by UNC-6. In the absence of UNC-6, UNC-40 is equally distributed and the HSN axon travels anteriorly in response to other cues. However, we find that a single amino acid change in the UNC-40 ectodomain causes randomly oriented asymmetric UNC-40 localization and a wandering axon phenotype. With UNC-6, there is normal UNC-40 localization and axon migration. A single UNC-6 amino acid substitution enhances the mutant phenotypes, whereas UNC-6 second-site amino acid substitutions suppress the phenotypes. We propose that UNC-40 mediates multiple signals to polarize and orient asymmetry. One signal triggers the intrinsic ability of HSN to polarize and causes randomly oriented asymmetry. Concurrently, another signal biases the orientation of the asymmetry relative to the UNC-6 gradient. The UNC-40 ectodomain mutation activates the polarization signal, whereas different forms of the UNC-6 ligand produce UNC-40 conformational changes that allow or prohibit the orientation signal.A major challenge for developmental neuroscience has been to understand how axons are able to detect and follow molecular gradients of different extracellular guidance cues. Attractive guidance cues are proposed to stimulate cytoplasmic signaling pathways that promote actin polymerization (Huber et al. 2003). Thus the direction of axon outgrowth is directly linked to the extracellular gradient of the guidance cue; i.e., there is greater extension on the side of the neuron that is closest to the source of the cue. Netrins are bifunctional guidance cues that are attractive to some axons but repulsive to others. Studies have shown that the axon response to netrin is determined by the composition of netrin receptors on the cell surface and the internal state of the growth cone (Round and Stein 2007). The UNC-6 (netrin) guidance cue in Caenorhabditis elegans interacts with the UNC-40 (DCC) receptor to mediate attraction (Hedgecock et al. 1990; Ishii et al. 1992; Chan et al. 1996). The AVM and HSN neurons are useful for studying UNC-40-mediated responses to UNC-6. The cell bodies of these neurons are situated on the lateral body wall and send a single axon ventrally during larval development.In AVM and HSN, a signaling module comprising UNC-6, UNC-40, phosphoinositide 3-kinase (PI3K), Rac, and MIG-10 (lamellipodin) is thought to transmit the directional information provided by the graded distribution of extracellular guidance cues to the internal cellular machinery that promotes directed outgrowth (Adler et al. 2006; Chang et al. 2006; Quinn et al. 2006, 2008). MIG-10 appears to provide an important link because this family of proteins can interact with proteins that promote actin polymerization, and it is associated with asymmetric concentrations of f-actin and microtubules in turning growth cones (Krause et al. 2004; Quinn et al. 2008). MIG-10 is observed as asymmetrically localized to the ventral site of axon outgrowth in developing HSN neurons. This MIG-10 localization is sensitive to the source of UNC-6. Normally, the source of UNC-6 is ventral; in the absence of UNC-6, there is an equal distribution of MIG-10 along the cell surface, whereas ectopic UNC-6 expression from dorsal muscles causes dorsal MIG-10 localization (Adler et al. 2006). The UNC-40 receptor is also asymmetrically localized in HSN, and this localization is also dependent on UNC-6 (Adler et al. 2006). UNC-40 signaling activates Rac GTPase, and MIG-10 interacts specifically with the activated Rac (Quinn et al. 2008). Therefore, the asymmetric activation of Rac through UNC-40 recruits asymmetric MIG-10 localization.By activating or directing components to the surface nearest the UNC-6 source, the asymmetric distribution of UNC-6 could polarize the neuron. However, an alternative idea is suggested from studies of chemotaxing cells. This model predicts that chemoattractant signaling involves two different elements: one that activates the intrinsic ability of cells to generate asymmetry and another that biases the orientation of the asymmetry (Wedlich-Soldner and Li 2003). The polarization signal does not depend on the spatial information provided by the chemoattractant gradient, whereas the orientation signal does. The asymmetric localization of the UNC-40 and MIG-10 signaling complex is suggestive of the segregation of signaling components into separate “front” and “rear” regions during chemotactic cell migration (Weiner 2002; Mortimer et al. 2008). It is hypothesized that this segregation is accomplished through short-range positive feedback mechanisms that promote the local production or recruitment of signaling molecules. In addition, a long-range inhibition mechanism globally increases the degradation of these molecules. Together such mechanisms could strongly amplify the asymmetric distribution of molecules needed for directed movement. This model has been put forth to explain why chemotactic cells polarize and move in a random direction when encountering a uniform chemoattractant concentration. Although the chemoattractant receptors may be uniformly stimulated across the surface of the cells, randomly oriented asymmetry can be established through these mechanisms.If the AVM and HSN neurons behave similarly to chemotactic cells, then uniformly stimulating UNC-40 receptors might similarly cause nonspecific asymmetric UNC-40 localization and axon migrations in varying directions. However, this is difficult to test in vivo. Unlike exposing chemotactic cells to a uniform concentration of a chemotractant in vitro, there is no reliable way to ensure that a neuron in vivo is exposed to a uniform concentration of UNC-6. The pseudocoelomic cavity of C. elegans is fluid filled, and UNC-6 expression patterns are spatially and temporally complex (Wadsworth et al. 1996). How the distribution of UNC-6 is affected by interactions with the extracellular matrix and cell surfaces is unknown.Using a genetic approach, we have found an UNC-40 mutation that triggers randomly oriented neuronal asymmetry. On the basis of the models proposed for chemotactic cells, we suggest that there is an UNC-6/UNC-40-mediated signal that specifically induces the neuron''s intrinsic ability to polarize. The UNC-40 mutation activates this signal; however, a second signal, which normally would concurrently orient asymmetry relative to the UNC-6 gradient, is not activated. Single amino acid changes within the UNC-6 ligand can enhance or suppress the randomly oriented asymmetry phenotype caused by the UNC-40 mutation. This suggests that specific UNC-40 conformations uncouple the activation of the different signals.  相似文献   

19.
The rapid evolution of essential developmental genes and their protein products is both intriguing and problematic. The rapid evolution of gene products with simple protein folds and a lack of well-characterized functional domains typically result in a low discovery rate of orthologous genes. Additionally, in the absence of orthologs it is difficult to study the processes and mechanisms underlying rapid evolution. In this study, we have investigated the rapid evolution of centrosomin (cnn), an essential gene encoding centrosomal protein isoforms required during syncytial development in Drosophila melanogaster. Until recently the rapid divergence of cnn made identification of orthologs difficult and questionable because Cnn violates many of the assumptions underlying models for protein evolution. To overcome these limitations, we have identified a group of insect orthologs and present conserved features likely to be required for the functions attributed to cnn in D. melanogaster. We also show that the rapid divergence of Cnn isoforms is apparently due to frequent coding sequence indels and an accelerated rate of intronic additions and eliminations. These changes appear to be buffered by multi-exon and multi-reading frame maximum potential ORFs, simple protein folds, and the splicing machinery. These buffering features also occur in other genes in Drosophila and may help prevent potentially deleterious mutations due to indels in genes with large coding exons and exon-dense regions separated by small introns. This work promises to be useful for future investigations of cnn and potentially other rapidly evolving genes and proteins.  相似文献   

20.
The use of bioinformatics tools require different sequence formats at various instances. Every tool uses specific set of formats for processing. Sequence in one format is often required in another format. Thus, there is a need for sequence format conversion. A number of such tools are available in the public domain. Here, we describe BIOFFORC as a file format converter. The tool is developed with a graphical user interface in PERL.

Availability

http://www.winningpath.com/biofforc/  相似文献   

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