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PubMed1992

Workshop on two-dimensional gel protein databases.

A workshop on two-dimensional gel electrophoresis (2-DE) protein database, organized by the Committee on Data for Science and Technology (CODATA) of the International Council of Scientific Unions Task Group on Biological Macromolecules, was held at the CODATA Secretariat in Paris on March 9, 1992. Eleven scientists from eight different countries represented various aspects of 2-DE analysis--namely, cellular protein database development and protein microsequencing methodologies. The purpose of the workshop was to explore means of integrating the rapidly expanding body of information on 2-DE resolved proteins from different laboratories. A major proposal emanating from the workshop was the establishment of an intermediary or "relational" 2-DE gel protein database. This intermediary database, which would catalogue pertinent information on 2-DE resolved proteins (experimental source, 2-DE loci, biological information, etc.) could be an adjunct to, and accessed through, the existing international protein sequence databanks. It would function as a pointer for researchers to the individual 2-DE protein databases where primary and more specialized 2-DE data would be housed.

Databases, Factual↗

PubMed1994

The human keratinocyte two-dimensional protein database (update 1994): towards an integrated approach to the study of cell proliferation, differentiation and skin diseases.

The master two-dimensional (2-D) gel database of human keratinocytes currently lists 3087 cellular proteins (2168 isoelectric focusing, IEF; and 919 none-quilibrium pH gradient electrophoresis, NEPHGE), many of which correspond to posttranslational modifications, 890 polypeptides have been identified (protein name, organelle components, etc.) using one or a combination of procedures that include (i) comigration with known human proteins, (ii) 2-D gel immunoblotting using specific antibodies (iii) microsequencing of Coomassie Brilliant Blue stained proteins, (iv) mass spectrometry and (v) vaccinia virus expression of full length cDNAs. These are listed both in alphabetical order and with increasing SSP number, together with their M(r), pI, cellular localization and credit to the investigator(s) that aided in the identification. Furthermore, we list 239 microsequenced proteins recorded in the database. We also report a database of proteins recovered from the medium of noncultured, unfractionated keratinocytes. This database lists 398 polypeptides (309 IEF; 89 NEPHGE) of which 76 have been identified. The aim of the comprehensive databases is to gather, through a systematic study of keratinocytes, qualitative and quantitative information on proteins and their genes that may allow us to identify abnormal patterns of gene expression and, ultimately, to pinpoint signaling pathways and components affected in various skin diseases, cancer included.

Amino Acid Sequence↗

PubMed1994

Protein family classification based on searching a database of blocks.

The most highly conserved regions of proteins can be represented as "blocks" of locally aligned sequence segments. Previously, an automated system was introduced to generate a database of blocks that is searched for local similarities using a sequence query. Here, we describe a method for searching this database that can also reveal significant global similarities. Local and global alignments are scored independently, so they can be used in concert to infer homology. A set of 7082 diverse sequences not represented in the database provided queries for testing this approach. The resulting distributions of scores led to guidelines for interpretation of search data and to the classification of 289 uncatalogued sequences into known groups. Thirty-eight of these relationships appear to be new discoveries. We also show how searching a database of blocks can be used to detect repeated domains and to find distinct cross-family relationships that were missed in searches of sequence databases.

Animals↗

PubMed1994

Coronary artery bypass grafting: the Society of Thoracic Surgeons National Database experience.

The need for accurate risk assessment has become an indispensable element in the practice of cardiac surgery. The Society of Thoracic Surgeons National Cardiac Surgery Database allows subscribing institutions to perform sophisticated patient risk assessment using traditional statistical tools and a newly developed risk model of operative mortality. The database experience with isolated coronary artery bypass grafting has been studied most closely at this point and serves as the basis for this report. The approach to operative risk assessment is presented along with an analysis of important risk factors in the practice of coronary artery surgery from 1980 through 1990. The database contains records of 80,881 patients undergoing coronary artery bypass grafting in numerous institutions from 1980 through 1990. These records were used to conduct a detailed analysis of risk factors associated with coronary operations in this time interval and to present statistical methods used to formulate a risk equation that allows one to predict the probability of operative death. In the course of this decade, there were clearly defined trends showing a statistically significant increase in adverse patient risk factors. The risk model has proven to be a reliable tool for predicting the probability of operative death in an individual patient and may be valuable in both patient counseling and medical decision making. Large multi-institutional databases of this type are key ingredients of modern operative risk assessment. A database containing a broad national experience of this type can represent an aggregate experience that may well approximate a universally accepted standard of care.

Adult↗

PubMed1994

A deductive database system for analyzing human nucleotide sequence data.

The analysis of the human genome is one of the most significant topics in both biology and medical science. There is a growing need for a well-designed database system for searching and analyzing the human genome data. We developed a deductive database system to search and analyze nucleotide sequence data derived from the GenBank primates data. A deductive database system is a next generation one and it contains an inference mechanism that can handle problems beyond the capabilities of classical database systems. Database queries are described in logical rules. These rules are simple even for molecular biologists who are not experts in computer programs because they are declarative and do not require the procedural commands that are usually used in computer programs. Furthermore, queries based on logical rules are powerful enough to express complicated biological problems. Particularly, recursive rules are suitable for examining secondary structures of nucleotide sequences. In our analysis of TfR's IRE, we noted five stem-and-loop structures.

Artificial Intelligence↗

PubMed1991

Statistical analysis in dBASE-compatible databases.

Database management in clinical and experimental research often requires statistical analysis of the data in addition to the usual functions for storing, organizing, manipulating and reporting. With most database systems, transfer of data to a dedicated statistics package is a relatively simple task. However, many statistics programs lack the powerful features found in database management software. dBASE IV and compatible programs are currently among the most widely used database management programs. d4STAT is a utility program for dBASE, containing a collection of statistical functions and tests for data stored in the dBASE file format. By using d4STAT, statistical calculations may be performed directly on the data stored in the database without having to exit dBASE IV or export data. Record selection and variable transformations are performed in memory, thus obviating the need for creating new variables or data files. The current version of the program contains routines for descriptive statistics, paired and unpaired t-tests, correlation, linear regression, frequency tables, Mann-Whitney U-test, Wilcoxon signed rank test, a time-saving procedure for counting observations according to user specified selection criteria, survival analysis (product limit estimate analysis, log-rank test, and graphics), and normal t and chi-squared distribution functions.

Database Management Systems↗

PubMed1992

Redesigning, implementing and integrating Escherichia coli genome software tools with an object-oriented database system.

This paper reports our exploratory work to redesign, implement and integrate a collection of genome software tools with an object-oriented database system. Our software tools deal with genome data from Escherichia coli K-12, a bacterium that has been studied intensively and provides richer data sets than any other living organism. The object-oriented DBMS used for the integration is ONTOS, a commercial object-oriented system from Ontologic Inc. This redesign and implementation task was performed in two steps. First, C programs were converted into C++, and then the C++ version programs were modified and integrated with an object-oriented modeling of the data to form an ONTOS database application. The first step helps us develop a conceptual view for a DBMS-independent object-oriented construct. The second step elucidates what additional DBMS-dependent modification steps are needed to provide persistency to the objects. Examples are included to illustrate steps of the redesign and implementation. Overall, the outcome of this project demonstrates that programs and data can be successfully integrated with an object-oriented database, while providing the objects with persistency and shareability. This paper includes discussions using concrete examples on what advantage the object-oriented database approach provides over the relational database approach.

Base Sequence↗

PubMed1992

PATMAT: a searching and extraction program for sequence, pattern and block queries and databases.

A program has been developed that provides molecular biologists with multiple tools for searching databases, yet uses a very simple interface. PATMAT can use protein or (translated) DNA sequences, patterns or blocks of aligned proteins as queries of databases consisting of amino acid or nucleotide sequences, patterns or blocks. The ability to search databases of blocks by 'on-the-fly' conversion to scoring matrices provides a new tool for detection and evaluation of distant relationships. PATMAT uses a pull-down, menu-driven interface to carry out its multiple searching, extraction and viewing functions. Each query or database type is recognized, reported, and the appropriate search carried out, with matches and alignments reported in windows as they occur. Any of the high scoring matches can be exported to a file, viewed and recalled as a query using only a few keystrokes or mouse selections. Searches of multiple database files are carried out by user selection within a window. PATMAT runs under DOS; the searching engine also runs under UNIX.

Amino Acid Sequence↗

PubMed1993

Searching for amino acid sequence motifs among enzymes: the Enzyme-Reaction Database.

Recently we have constructed a database--the Enzyme-Reaction Database--which links a chemical structure to amino acid sequences of enzymes that recognize the chemical structure as their ligand. The total number of enzymes registered in the database is 1103 with 6668 NBRF-PIR entry codes and 1756 chemical compounds. The chemical structures and chemical names for 842 compounds are registered in the Chemical-Structure Database on the MACCS system. For each enzyme, the sequences were divided into clusters, and multiply aligned in each cluster to extract a conserved sequence. A total of 158,781 five-residue-long fragments were constructed from 433 conserved sequences and compared among different clusters of different enzymes. One of these motifs shared by different enzymes was S-G-G-L-D. The motif was conserved in both argininosuccinate synthase (EC 6.3.4.5) and asparagine synthase (glutamine-hydrolysing) (EC 6.3.5.4). This result showed that the database was useful for the analysis of the relationship between chemical structures and amino acid sequence motifs.

Algorithms↗

PubMed1992

Corruption of genomic databases with anomalous sequence.

We describe evidence that DNA sequences from vectors used for cloning and sequencing have been incorporated accidentally into eukaryotic entries in the GenBank database. These incorporations were not restricted to one type of vector or to a single mechanism. Many minor instances may have been the result of simple editing errors, but some entries contained large blocks of vector sequence that had been incorporated by contamination or other accidents during cloning. Some cases involved unusual rearrangements and areas of vector distant from the normal insertion sites. Matches to vector were found in 0.23% of 20,000 sequences analyzed in GenBank Release 63. Although the possibility of anomalous sequence incorporation has been recognized since the inception of GenBank and should be easy to avoid, recent evidence suggests that this problem is increasing more quickly than the database itself. The presence of anomalous sequence may have serious consequences for the interpretation and use of database entries, and will have an impact on issues of database management. The incorporated vector fragments described here may also be useful for a crude estimate of the fidelity of sequence information in the database. In alignments with well-defined ends, the matching sequences showed 96.8% identity to vector; when poorer matches with arbitrary limits were included, the aggregate identity to vector sequence was 94.8%.

Base Sequence↗

PubMed1994

The European Bioinformatics Institute (EBI) databases.

This paper describes the databases and services of the European Bioinformatics Institute (EBI). In collaboration with DDBJ and GenBank/NCBI, the EBI maintains and distributes the EMBL Nucleotide Sequence Database, Europe's primary nucleotide sequence data resource. The EBI also maintains and distributes the SWISS-PROT Protein Sequence Database, in collaboration with Amos Bairoch of the University of Geneva. Over thirty additional specialist molecular biology databases, as well as software and documentation of interest to molecular biologists, are also available. The EBI network services include database searching, entry retrieval, and sequence similarity searching facilities.

Amino Acid Sequence↗

PubMed1996

Histone Sequence Database: a compilation of highly-conserved nucleoprotein sequences.

By searching the current protein sequence databases using sequences from human and chicken histones H1/H5, H2A, H2B, H3 and H4, a database of aligned histone protein sequences with statistically significant sequence similarity to the search sequence was constructed. In addition, a nucleotide sequence database of the corresponding coding regions for these proteins has been assembled. The region of each of the core histones containing the histone fold motif is identified in the protein alignments. The database contains >1300 protein and nucleotide sequences. All sequences and alignments in this database are available through the World Wide Web at http://www.ncbi.nlm.nih.gov/Baxevani/HISTO NES.

Amino Acid Sequence↗

PubMed1994

Comparison of systematic search and database methods for constructing segments of protein structure.

Two principal methods of determining the conformation of short pieces of polypeptide backbone in proteins have been developed: using a database of known structures and systematically generating all conformations. In this paper, we compare the effectiveness of these two techniques. The completeness of the database for segments of different lengths is examined and it is found to contain most conformations for segments seven residues long, but to deteriorate rapidly for longer regions. When the database segment is to be incorporated into the rest of a structure, at least seven residues are required to build four new residues, because of the need to position the segment relative to the rest of the structure. It is found that such positioning using flanking residues results in large errors in the inserted region. We conclude that the database method is currently not effective for comparative modeling, even for short segments. The systematic search procedure is found to generate almost all structures of short segments found in proteins. In contrast to the database method, low root mean square error structures are obtained for a set of trial segments embedded in the rest of a protein structure. Thus, it should be considered the method of choice.

Computer Simulation↗

PubMed1995

SubtiList: a relational database for the Bacillus subtilis genome.

In the framework of the international collaborative project aiming to sequence the whole Bacillus subtilis chromosome, we have created a relational database for managing and analysing information associated with the molecular genetics of this bacterium: SubtiList. It allows recovery of non-redundant DNA sequences of the B. subtilis genome, as well as related information, i.e. genes, proteins, etc. A logical structure has been designed with appropriate links between the different objects, and a set of procedures has been implemented for data updating and management. The database is organized around a core constituted by all known contigs of B. subtilis, i.e. sets of non-redundant sequences created from original entries in the EMBL data library. A user-friendly interface has been developed to make the database easy to consult. Sequence analysis tools have been integrated into the database, such as a program for rapid similarity searching of protein data banks, and a powerful DNA pattern searching program. Thanks to the consistency of SubtiList, we have performed a codon usage analysis by Factorial Correspondence Analysis, and a study of the distribution of the isoelectric points of known proteins of B. subtilis. The SubtiList database is available through anonymous ftp (address 'ftp.pasteur.fr' or IP number 157.99.64.12, directory '/pub/GenomeDB/SubtiList').

Algorithms↗

PubMed1992

The development of a virtual database to provide on-line access to a large archive of clinical data.

The archival database of the HELP Hospital Information System at LDS Hospital is too large to be stored on line. The archival data are important for clinical and research applications. Demountable disk packs have been used to store the archival database. This method of storage has four significant disadvantages. A virtual database was developed to overcome the limitations of this data-management scheme. This virtual database enables the transparent use of appropriate low-cost network-based storage technology to provide on-line availability of the entire archive of clinical data. The virtual database successfully resolves the problems associated with disk packs, and opens the door to enhanced use of the data for clinical and research applications.

Computer Storage Devices↗

PubMed1991

Medical Facts File: a self service database of reference information.

The Dahlgren Memorial Library, Georgetown University Medical Center, will demonstrate Medical Facts File, a newly developed in-house database of general medical information. The file content emerged from the library's experience with commonly asked reference questions and the need to develop a database as an online source for users seeking quick answers to medical queries. Medical Facts File joins a growing family of over 18 databases which comprise Georgetown's IAIMS Knowledge Network. Use scenarios will demonstrate how an online search is initiated, either directly or as a prompt from one of the other online databases. The design of Medical Facts File at the Dahlgren Memorial Library began in late 1989 with a publishing section on instructions for authors planning to submit manuscripts to a variety of prominent medical journals. Since then, seven sections have been identified for the database. Three sections are highlighted for presentation, although work on the project is on-going. Medical Facts File is an easy-to-use, time saving system that facilitates tedious searching through a multitude of library sources. It provides users with a self-service, information look-up system.

Databases, Factual↗

PubMed1991

Modeling uncertainty in a database for physical gene mapping data.

We are building a database for the storage, retrieval, and graphical display of physical gene mapping data. To allow this information to be analyzed robustly, such a database must confront the inherent uncertainty of the data as a central design issue. The paper describes the overall database design, the types of gene mapping data which the system will contain, the types of uncertainty in the data, and certain of the design issues involved in allowing the database to handle uncertainty in a comprehensive fashion. Only if a full appreciation of uncertainty is built into the system from its inception will a physical gene mapping database be truly robust and successful.

Chromosome Mapping↗

PubMed1989

A dedicated database program for cataloging recombinant clones and other laboratory products of molecular biology technology.

A novel computer database program dedicated to storing, cataloging, and accessing information about recombinant clones and libraries has been developed for the IBM (or compatible) personal computer. This program, named CLONES, also stores information about bacterial strains and plasmid and bacteriophage vectors used in molecular biology. The advantages of this method are improved organization of data, fast and easy assimilation of new data, automatic association of new data with existing data, and rapid retrieval of desired records using search criteria specified by the user. Individual records are indexed in the database using B-trees, which automatically index new entries and expedite later access. The use of multiple windows, pull-down menus, scrolling pick-lists, and field-input techniques make the program intuitive to understand and easy to use. Daughter databases can be created to include all records of a particular type, or only those records matching user-specified search criteria. Separate databases can also be merged into a larger database. This computer program provides an easy-to-use and accurate means to organize, maintain, access, and share information about recombinant clones and other laboratory products of molecular biology technology.

Database Management Systems↗