Table of content

Open Access Bioinformatics

ISSN/EISSN: 11792701
Subject: Biology
Publisher: Dove Medical Press
Country: United Kingdom
Language: English
Start year 2010
Publication fee: Yes --- Further Information

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Table of content: 2010 volume:2010 issue:default

Article
Balancing false discovery and false negative rates in selection of differentially expressed genes in microarrays

Authors: Byung S Park --- Motomi Mori
Pages: 1-9
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Byung S Park1,2,3, Motomi Mori1,2,31Division of Biostatistics, Department of Public Health and Preventive Medicine, 2Biostatistics Shared Resource, Knight Cancer Institute, 3Biostatistics and Design Program, Oregon Clinical and Translational Science Institute, Oregon Health and Science University, Portland, OR, USAAbstract: Genome-wide mRNA expression profiling using microarrays is widely available today, yet analysis and interpretation of the resulting high dimensional data continue to be a challenge for biomedical scientists. In a typical microarray experiment, the number of biological samples is quite modest compared with the number of genes on a microarray, and a probability of falsely declaring differential expression is unacceptably high without any adjustment for multiple comparisons. However, a stringent multiple comparison procedure can lead to an unacceptably high false negative rate, potentially missing a large fraction of truly differentially expressed genes. In this paper we propose a new “balancing factor score” (BFS) method for identifying a set of differentially expressed genes. The BFS method combines a traditional P value criterion with any other informative factors (referred to as balancing factors) that may help to identify differentially expressed genes. We evaluate the performance of the BFS method when the observed fold change is used as a balancing factor in a simulation study and show that the BFS method can substantially reduce the false negative rate while maintaining a reasonable false discovery rate.Keywords: balancing factor score method, microarrays, multiple comparisons, false discovery rate, false negative rate

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Article
Analysis of botulinum neurotoxin serotype A metalloprotease inhibitors: analogs of a chemotype for therapeutic  development in the context of a three-zone pharmacophore

Authors: James C Burnett --- Bing Li --- Ramdas Pai --- et al
Pages: 11-18
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James C Burnett1, Bing Li2, Ramdas Pai2, Steven C Cardinale2, Michelle M Butler2, Norton P Peet2, Donald Moir2, Sina Bavari3, Terry Bowlin21Target, Structure-Based Drug Discovery Group, SAIC-Frederick, Inc., National Cancer Institute at Frederick; Frederick, MD 21702, USA; 2Microbiotix, Inc., Worcester, MA 01605, USA; 3Division of Integrated Toxicology,  United States Army Medical Research Institute of Infectious Diseases, Frederick, MD 21702, USAAbstract: Botulinum neurotoxins (BoNTs), and in particular serotype A, are the most poisonous of known biological substances, and are responsible for the flaccid paralysis of the disease state botulism. Because of the extreme toxicity of these enzymes, BoNTs are considered highest priority biothreat agents. To counter BoNT serotype A (BoNT/A) poisoning, the discovery and development of small molecule, drug like inhibitors as post intoxication therapeutic agents is being pursued. Specifically, we are focusing on inhibitors of the BoNT/A light chain (LC) (ie, a metalloprotease) subunit, since such compounds can enter neurons and provide post intoxication protection of the enzyme target substrate. To aid/facilitate this drug development effort, a pharmacophore for inhibition of the BoNT/A LC subunit was previously developed, and is continually being refined via the incorporation of novel and diverse inhibitor chemotypes. Here, we describe several analogs of a promising therapeutic chemotype in the context of the pharmacophore for BoNT/A LC inhibition. Specifically, we describe: 1) the pharmacophoric ‘fits’ of the analogs and how these ‘fits’ rationalize the in vitro inhibitory potencies of the analogs, and 2) pharmacophore refinement via the inclusion of new components from the most potent of the presented analogs.Keywords: botulinum, neurotoxin, inhibitor, pharmacophore, metalloprotease, biothreat

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Article
Refinement of rigid-body protein–protein docking using backbone and side-chain minimization with a coarse-grained model

Authors: Albert Solernou --- Juan Fernández-Recio
Pages: 19-27
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Albert Solernou, Juan Fernández-RecioLife Sciences Department, Barcelona Supercomputing Center, Barcelona, SpainAbstract: Understanding protein–protein recognition is one of the main goals in structural biology. Most of the key biological processes involve the formation of specific protein complexes, for which a detailed structural knowledge is essential to understand the mechanism of protein association and their functional implications. Computational docking methods are currently able to predict the structure of a protein–protein complex with a high degree of accuracy in some cases. However, in the majority of cases, with conformational movements upon binding, we have to go beyond the current rigid-body approach and introduce flexibility. Given the difficulties of using full-atom descriptions during flexible docking, we need to focus our efforts in coarse-grain models. Here, we have implemented and tested a version of the united residue (UNRES) forcefield for protein–protein docking refinement. The results indicate improvement in the geometry of the docking solutions, and better docking energy landscapes, although in general, the scoring did not improve with respect to rigid-body pyDock function. However, as opposed to other scoring algorithms, the UNRES scoring does not seem to be biased towards cases that are over-represented in the structural databases (typically enzyme-inhibitor and antibody-antigen cases). This consistency among all types of complexes suggests its use as a solid basis for developing better unbiased scoring methods.Keywords: molecular recognition, structural prediction, protein–protein association, global energy

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Article
Computational methods for the identification of microRNA targets

Authors: Yang Dai --- Xiaofeng Zhou
Pages: 29-39
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Yang Dai1, Xiaofeng Zhou21Department of Bioengineering, Department of Computer Science, College of Engineering, 2Center for Molecular Biology of Oral Diseases, College of Dentistry, and Graduate College, UIC Cancer Center, University of Illinois at Chicago, Chicago, IL, USAAbstract: MicroRNAs are pivotal regulators of development and cellular homeostasis. They act as post-transcriptional regulators, which control the stability and translation efficiency of their target mRNAs. The prediction of microRNA targets and detection of microRNA-mRNA regulatory modules (MRMs) are crucial components for understanding of microRNA functions. Numerous computational methods for microRNA target prediction have been developed. Computationally-predicted targets have been recently used in the integrative analysis of microRNA and mRNA expression analysis to identify microRNA targets and MRMs. In this article we review these recent developments in the integrative analysis methods. We also discuss the remaining challenges and our insights on future directions.Keywords: microRNA target prediction, integrative analysis, microRNA regulatory mechanism, microRNA profiling, mRNA expression profiles

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Article
Efficiency of a hierarchical protocol for high throughput structure-based virtual screening on GRID5000 cluster grid

Authors: Leo Ghemtio --- Emmanuel Jeannot --- Bernard Maigret
Pages: 41-53
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Leo Ghemtio1, Emmanuel Jeannot2,3, Bernard Maigret11LORI A, Groupe ORPAILLEUR, 2LORI A, Groupe ALGORI LLE, Campus scientifique, Nancy Université, Vandoeuvre-lès-Nancy Cedex, France; 3LABRI , Groupe Runtime, Cours de la Libération, Bordeaux Université, Talence Cedex, FranceAbstract: Most modern computational techniques in the drug discovery areas put demands on large computer resources. Grid computing offers a powerful alternative way of running computationally intensive applications. One field of the drug innovation process that can benefit greatly from the use of grid resources is the high-throughput virtual screening approach for docking huge chemical compound libraries into known protein-binding sites. The use of computational grids is the combination of computer resources from multiple administrative domains, heterogeneous, and geographically dispersed applications to a common task that requires a great number of computer-processing cycles or the need to process large amounts of data. This study detailed a screening campaign, on Grid5000 cluster grid computing infrastructure, concerning the ZINC database, from which a subset of ∼600,000 “drug-like” molecules was extracted, against three structures of the liver-X receptor β (LXR β). A funnel strategy was used for that purpose, starting from a fast but simple shape matching procedure and achieved with more complex molecular dynamics simulations. From a total of ∼91 million three-dimensional conformations which were generated at the beginning of the funnel and after intermediate filtering steps, the process ended with 45 putative hits. The GRID5000 is a highly reconfigurable, controllable, and monitorable experimental cluster grid, connecting nine sites geographically distributed in France, and featuring more than 3,200 processors and 5,700 cores. To hide the complexity of the grid system from the user, the GRID5000 has been used through the virtual screening manager for grid computing (VSM-G) platform, dedicated to in silico screening and to provide maximum computing power by using grid resources efficiently. The whole screening process required around 82 days (78 days of pre-processing and 3.6 days for the docking funnel itself) and utilized 3,144 nodes over nine sites. The use of grid infrastructures and hierarchical filtering protocol enable us to perform evaluations of the binding capabilities of millions of compounds on several conformations of a given target and propose that, with a low cost, most promising compounds for in vitro tests.Keywords: high-throughput virtual screening, molecular filtering, docking, liver-X receptors, grid computing, molecular dynamics simulation

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Article
Modeling short-term antidepressant responsiveness with artificial neural networks

Authors: Eugene Lin --- Po See Chen --- I Hui Lee --- et al
Pages: 55-60
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Eugene Lin1, Po See Chen2,6, I Hui Lee2, Hui Hua Chang3, Po-Wu Gean4, Yen Kuang Yang2, Ru-Band Lu2,51Vita Genomics, Inc., Taipei, Taiwan; 2Department of Psychiatry, 3Institute of Biopharmaceutical Sciences, 4Department of Pharmacology, 5Institute of Behavioral Medicine, 6Department of Psychiatry, National Cheng Kung University Hospital, Dou-Liou Branch, TaiwanAbstract: Due to the varying nature of patient response to different types and even dosages of the same antidepressant, doctors currently prescribe antidepressants on a trial and error basis. Therefore, it is highly desirable, both clinically and economically, to establish tools that distinguish responders from non-responders and to predict possible outcomes of the antidepressant treatments. The overall effectiveness of treatment using antidepressants may thus be optimized. Common genetic polymorphisms, such as single nucleotide polymorphisms (SNPs) can be used in clinical association studies to determine the contribution of genes to drug efficacy. In this work we developed a prediction model resulting from the analysis of clinical factors such as SNPs, age, baseline Hamilton Rating Scale for Depression (HAM-D) score, antidepressant groups, and gender of depression patients. We used it to predict the responsiveness of antidepressant treatment. By using candidate genes reported in the literature, we selected four SNPs that were strongly relevant to antidepressant efficacy. Our study population consisted of Taiwanese patients with major depression recruited from the National Cheng Kung University Hospital. The genotyping data was generated in the high-throughput genomics lab of Vita Genomics, Inc. With the wrapper-based feature selection approach, we employed multilayer feedforward neural network (MFNN) and logistic regression as a basis for comparisons. Our data revealed that the MFNN models were superior to the logistic regression model. The MFNN approach provides an efficient way to develop a tool for distinguishing responders from nonresponders prior to treatments. Our preliminary results showed that the MFNN algorithm is effective for deriving models for pharmacogenomics studies and for providing the link from clinical factors such as SNPs to the responsiveness of antidepressants in clinical association studies.Keywords: antidepressants, artif icial neural networks, major depressive disorder, pharmacogenomics, single nucleotide polymorphisms

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Article
Molecular docking studies on the activity of naturally occurring pyranochalcones on the transcriptional regulator enzyme of Pseudomonas putida

Authors: Satya B Paul --- Sudip Choudhury
Pages: 61-66
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Satya B Paul1, Sudip Choudhury21Department of Chemistry, Assam University, Silchar-788011, Assam, India; 2Department of Chemistry, Gurucharan College, Silchar-788004, Assam, IndiaAbstract: The paper reports the in-silico docking results of 10 naturally occurring pyranochalcones on the transcriptional regulator (TtgR) enzyme, which is a key efflux pump TtgABC operon repressor in the Gram-negative bacteria Pseudomonas putida (DOT-T1E strain) as the receptor. TtgR is a multidrug-binding protein and regulates one of the key mechanisms of its antibiotic resistance by active extrusion of toxic compounds through the membrane-bound efflux pumps. Although the bacteria exhibits resistance against a number of antibiotics, one natural pyranochalcone Pongachalcone I has been reported to be active against it. The presence of alkoxy moiety in the aromatic side unit of the pyranochalcones seems to be instrumental in bindingKeywords: TtgR, docking, in-silico, antibiotic resistance

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Article
Assessing 3D scores for protein structure fragment mining

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Frédéric Guyon1, Pierre Tufféry1,21MTi, INSERM UMR-S973, Université Paris Diderot-Paris 7, Paris, France; 2RPBS, Université Paris Diderot-Paris 7, Paris, FranceAbstract: Quantifying the 3D similarity between two proteins is a difficult task that has motivated the assessment of several 3D scores. New developments in protein modeling and analysis have led to the emergence of new interest towards mining structures at the local level. We assess in the context of fragment mining several dissimilarity scores. We revisit the concept of mirror conformation previously introduced at the level of complete structures and extend it to the more local level. We also consider an explicit criterion measuring the fragment boundary discrepancies. Whereas classical criteria such as the root mean square deviation (RMSd) fail to identify similar shapes in a consistent way, we show that local mirror and boundary mismatch filtering greatly supplements classical scores to select significant matches. The geometrical conditions defined by such criteria can be considered as signatures of fragment similarity. Furthermore, it is possible to tune the degree of similarity depending on the size of the mirrors accepted. This results in a more intuitive perception of the concept of similarity, and opens new perspectives for the rapid mining of large collections of structures.Keywords: protein fragments, similarity, distance, mining

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Article
Influence of SMAD1 gene in osteoporosis: A bioinformatics approach

Authors: An --- Anabarasu --- Arpita Kundu
Pages: 79-87
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Anand Anabarasu, Arpita KunduBioinformatics Division, School of Biosciences and Technology, VIT University, Tamil Nadu, India.Abstract: In the present study we have analyzed the role of SMAD family member 1 protein (SMAD1) gene products in relation to bone morphogenesis and osteoporosis. Out of 1045 single nucleotide polymorphisms (SNP) investigated, we find that one nonsynonymous SNP (nsSNP), rs1804647, to have significant damaging effects as predicted by all the tools used in the analysis. This nsSNP resulted in a change of amino acid from a positive charged residue, Lysine, to a strong negatively charged residue, Glutamate, and hence the change of residue with opposite charges might lead to structural defects and result in altered function. The results presented in this report will be a good starting point for genetic analysis of SMAD1 genes in patients with osteoporosis which might lead to more conclusive evidence of the association of this gene with osteoporosis.Keywords: osteoporosis, nsSNP, SMAD1, rs1804647

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Article
Increment of diversity with quadratic discriminant analysis – an efficient tool for sequence pattern recognition in bioinformatics

Authors: Jun Lu --- Liaofu Luo --- Lirong Zhang --- et al
Pages: 89-96
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Jun Lu1, Liaofu Luo2, Lirong Zhang2, Wei Chen2, Ying Zhang1,21Department of Physics, Inner Mongolia University of Technology, Hohhot 010051, China; 2Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, ChinaAbstract: Accompanying the rapid development of genome research, how to correctly ­recognize functional sites and structural modes of DNA and protein sequences has become a great challenge to bioinformatics. Therefore, a great number of algorithms and tools have been proposed and applied to sequence pattern recognition. Increment of Diversity with Quadratic Discriminant analysis (IDQD) is one of the efficient computational tools. In this article we shall introduce the main points of IDQD method and review its application in DNA and protein sequence pattern recognition, and finally give some discussions on the prospects of the approach.Keywords: Increment of Diversity, Quadratic Discriminant analysis, sequence pattern recognition

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Article
Antigenic epitopes prediction and MHC binder of a paralytic insecticidal toxin (ITX-1) of Tegenaria agrestis (hobo spider)

Authors: AG Ingale
Pages: 97-103
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AG IngaleDepartment of Biotechnology, School of Life Sciences, North Maharashtra University, Jalgaon, IndiaAbstract: Spider peptide toxins with nanomolar affinities for their receptors are promising pharmacological tools for understanding the physiological role of ion channels and as leads for the development of novel therapeutic agents and strategies for ion channel-related diseases. Paralytic insecticidal toxin (Tegenaria agrestis) involved multiple antigenic components to direct and empower the immune system to protect the host from infection. MHC molecules are cell surface proteins, which take active part in host immune reactions and involvement of MHC class in response to almost all antigens, and it affects specific sites. Predicted MHC binding regions act like red flags for specific antigens and generate an immune response against the parent antigen. So a small fragment of antigen can induce an immune response against whole antigen. This theme is implemented in designing subunit and synthetic peptide vaccines. In this study, we analyzed secondary structure and antigenic determinants, which form antibodies against infection. The method integrates prediction of peptide MHC class binding and solvent accessible regions. Antigenic epitopes of paralytic insecticidal toxin are important antigenic determinants against the various toxic reactions and infections. There are 3 antigenic determinants in sequence. The results show highest pick at position 4–25 (QLMICLVLLPCFFCEPDEICRA) amino acid residue and 34–51 (YKSNVCNGCGDQVAACEA) amino acid residue.Keywords: antigen prediction, modeling, ITX-1

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Article
Utility and applications of synoptic reporting in pathology

Authors: Waqas Amin --- S Joseph Sirintrapun --- Anil V Parwani
Pages: 105-112
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Waqas Amin1, S Joseph Sirintrapun3, Anil V Parwani1,21Department of Biomedical Informatics, 2Department of Pathology University of Pittsburgh, Pittsburgh, PA, USA; 3Department of Pathology, Emory University, Atlanta, GA, USABackground: Synoptic reports in routine pathology practice provide composite documents that include information from morphology and molecular technologies. It is clear and accurate structured information and developed by incorporating standardized data elements in the form of checklist for pathology reporting. This facilitates pathologists to document their findings and ultimately improve the overall quality of pathology reports.Objectives: The goal of this review article is to discuss (1) the importance of synoptic reporting in pathology, (2) utility and applications, (3) its impact on pathology reporting and patient care, and (4) the challenges and barriers of implementing synoptic reporting. Pertinent literature will also be reviewed.Design: The synoptic reporting system provides a complete set of data elements in the form of synoptic templates or “worksheets” for pathology tumor reporting based on the World Health Organization (WHO) Classification and the College of American Pathologists (CAP) Cancer Checklists. These standards provide most updated and supplemented classification scheme, specimen details, and staging as well as prognostic information. Data from synoptic reporting tool can be imported to a relational database where they are organized and efficiently searched and retrieved. Since search and retrieval are streamlined, synoptic databases enhance basic ­science, clinical, and translational cancer research.Conclusion: Synoptic reporting facilitates a standard based structured method for entering the diagnostic and prognostic information in accurate and consistent fashion for a particular ­pathology specimen, thus reducing transcription services, specimen turnaround time, and typographical and transcription errors. The structured data can be imported into the Laboratory Information Service (LIS) database, which facilitates swift data access and improved communication for cancer management. Finally, these synoptic templates act as a robust medium of high-quality data from the various biospecimens, which can be shared across multiple on-going research projects to enhance basic and translational research.Keywords: synoptic reporting, pathology

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Article
Computational studies of NMDA receptors: differential effects of neuronal activity on efficacy of competitive and noncompetitive antagonists

Authors: Nicolas Ambert --- Renaud Greget --- Olivier Haeberlé --- et al
Pages: 113-125
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Nicolas Ambert1, Renaud Greget1,2, Olivier Haeberlé2, Serge Bischoff1, Theodore W Berger3,4, Jean-Marie Bouteiller3,4, Michel Baudry3,41Rhenovia Pharma, Mulhouse, France; 2MIPS, Mulhouse, France; 3Neuroscience Program, 4Department of Biomedical Engineering and Center for Neural Engineering, University of Southern California, Los Angeles, CA, USAAbstract: N-methyl-D-aspartate receptors (NMDARs) play important physiological as well as pathological roles in the central nervous system (CNS). While NMDAR competitive antagonists, such as D-2-amino-5-phosphopentanoic acid (AP5) have been shown to impair learning and memory, the noncompetitive antagonist, memantine, is paradoxically beneficial in mild to moderate Alzheimer’s disease (AD) patients. It has been proposed that differences in kinetic properties could account for antagonist functional differences. Here we present a new elaborated kinetic model of NMDARs that incorporates binding sites for the agonist (glutamate) and coagonist (glycine), channel blockers, such as memantine and magnesium (Mg2+), as well as competitive antagonists. We first validated and optimized the parameters used in the model by comparing simulated results with a wide range of experimental data from the literature. We then evaluated the effects of stimulation frequency and membrane potential (Vm) on the characteristics of AP5 and memantine inhibition of NMDARs. Our results indicated that the inhibitory effects of AP5 were not strongly affected by Vm, but decreased with increasing stimulation frequency. In contrast, memantine inhibitory effects decreased with both increasing Vm and stimulation frequency. They support the idea that memantine could provide tonic blockade of NMDARs under basal stimulation conditions without blocking their activation during learning. Moreover they underline the necessity of considering receptor kinetics and the value of the biosimulation approach to better understand mechanisms of drug action and to identify new ways of regulating receptor function.Keywords: kinetic model, stimulation frequency, memantine, AP5, biosimulation, systems neurobiology

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Article
The interpretation of protein structures based on graph theory and contact map

Authors: Mahnaz Habibi --- Changiz Eslahchi --- Mehdi Sadeghi --- et al
Pages: 127-137
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Mahnaz Habibi1, Changiz Eslahchi1, Mehdi Sadeghi2, Hamid Pezashk3,4,51Faculty of Mathematics, Shahid-Beheshti University, GC, Tehran, Iran; 2National Institute of Genetic Engineering and Biotechnology, Tehran, Iran; 3School of Mathematics, Statistics and Computer Sciences, College of Science, University of Tehran, Tehran, Iran; 4Center of Excellence in Biomathematics, College of Science, University of Tehran, Tehran, Iran; 5Bioinformatics Group, School of Computer Science, IPM, Tehran, IranPurpose: The analysis of a protein’s structure allowing detailed exploration of the protein’s biological function is one of the most challenging problems in bioinformatics. There are efficient algorithms to calculate main properties of a protein structure, such as packing density, buried or surface residues, and accessible surface area. But these algorithms need the three-dimensional (3D) coordinates of the proteins.Methods: We used the contact map of a protein to construct a graph. By considering several features of the corresponding graph, we proposed some algorithms to discuss the above-mentioned properties of a protein. We also introduced a new measure for the hydrophobicity of an amino acid by defining an average degree for the amino acid as a vertex on the graph.Results: We compared our results with those obtained by some other existing algorithms. We found strong correlations between the popular methods, which use 3D coordinates, and our methods, which only use a predicted contact map.Conclusion: Many features of a protein can be predicted without having 3D coordinates, based on the contact map of the protein. The programs are freely available from http://www.bioinf.cs.ipm.ir/softwares/asa/asa.rar.Keywords: accessible surface area, buried residue, surface residue, packing density, hydrophobic

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Article
A method for ranking compounds based on their relative toxicity using neural networking, C. elegans, axenic liquid culture, and the COPAS parameters TOF and EXT

Authors: Martine Ferguson --- Marc Boyer --- Robert Sprando
Pages: 139-144
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Martine Ferguson1, Marc Boyer1, Robert Sprando21United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Food Defense Communication and Emergency Response, Division of Public Health and Biostatistics, College Park, MD, USA; 2United States Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Applied Research and Safety Assessment, Division of Toxicology, Laurel, MD, USAAbstract: Caenorhabditis elegans (L1s) were exposed to (in order of decreasing toxicity) sodium arsenite, sodium fluoride, caffeine, valproic acid, sodium borate, or dimethyl sulfoxide in C. elegans habitation medium (CeHM) for 72 consecutive hours. At this time point nematode growth and development were assessed using a Complex Object Parametric Analyzer and Sorter (COPAS™). The COPAS generated biomarkers of growth (time of flight [TOF] – a measure of axial length) and development (extinction [EXT] – a measure of optical density) were subsequently utilized to rank compounds according to their relative toxicity, as measured by the rat oral LD-50, using artificial neural network methods. Neural network methods were utilized to analyze this data because of their ability to model nonlinear endpoints and a multilayer perceptron neural network method was used because of its capability to function well in the presence of collinearity. Using a neural network approach we found that the LD-50 was correctly predicted 96% of the time. The present study demonstrates that neural network methods can be utilized to rank compounds according to their relative toxicity using COPAS-generated data (TOF and EXT) obtained from exposing a large number of nematodes to water-soluble compounds in axenic liquid culture.Keywords: neural network, TOF, EXT, COPAS, C. elegans, rat oral LD-50

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Article
Microarray oligonucleotide probe designer: a Web service

Authors: Viren C Patel --- Kajari Mondal --- Amol Carl Shetty --- et al
Pages: 145-155
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Viren C Patel1*, Kajari Mondal1*, Amol Carl Shetty1*, Vanessa L Horner1, Jirair K Bedoyan2, Donna Martin2,3, Tamara Caspary1, David J Cutler1, Michael E Zwick11Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA; 2Department of Pediatrics, 3Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; *These authors contributed equally to this work.Abstract: Methods of genomic selection that combine high-density oligonucleotide microarrays with next-generation DNA sequencing allow investigators to characterize genomic variation in selected portions of complex eukaryotic genomes. However, choosing the specific oligonucleotides to be used can pose a major technical challenge. To address this issue, we have developed a software package called MOPeD (microarray oligonucleotide probe designer), which automates the process of designing genomic selection microarrays. This Web-based software allows individual investigators to design custom genomic selection microarrays optimized for synthesis with Roche NimbleGen’s maskless photolithography. Design parameters include uniqueness of the probe sequences, melting temperature, hairpin formation, and the presence of single-nucleotide polymorphisms. We generated probe databases for the human, mouse, and rhesus macaque genomes and conducted experimental validation of MOPeDdesigned microarrays in human samples by sequencing the human X chromosome exome, where relevant sequence metrics indicated superior performance relative to a microarray designed by the Roche NimbleGen proprietary algorithm. We also performed validation in the mouse to identify known mutations contained within a 487-kb region from mouse chromosome 16, the mouse chromosome 16 exome (1.7 Mb), and the mouse chromosome 12 exome (3.3 Mb). Our results suggest that the open source MOPeD software package and Web site (http://moped.genetics.emory.edu/) will make a valuable resource for investigators in their sequence-based studies of complex eukaryotic genomes.Keywords: genomic selection, oligonucleotide, microarray, next-generation sequencing, software 

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Table of content: 2010 volume:2010 issue:default