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At least 271 records · Page 15Linked to original sources

Privacy protection in HealthGrid: distributing encryption management over the VO.

Grid technologies have proven to be very successful in tackling challenging problems in which data access and processing is a bottleneck. Notwithstanding the benefits that Grid technologies could have in Health applications, privacy leakages of current DataGrid technologies due to the sharing of data in VOs and the use of remote resources, compromise its widespreading. Privacy control for Grid technology has become a key requirement for the adoption of Grids in the Healthcare sector. Encrypted storage of confidential data effectively reduces the risk of disclosure. A self-enforcing scheme for encrypted data storage can be achieved by combining Grid security systems with distributed key management and classical cryptography techniques. Virtual Organizations, as the main unit of user management in Grid, can provide a way to organize key sharing, access control lists and secure encryption management. This paper provides programming models and discusses the value, costs and behavior of such a system implemented on top of one of the latest Grid middlewares. This work is partially funded by the Spanish Ministry of Science and Technology in the frame of the project Investigación y Desarrollo de Servicios GRID: Aplicación a Modelos Cliente-Servidor, Colaborativos y de Alta Productividad, with reference TIC2003-01318.

Databases as Topic↗

Should statisticians reporting to data monitoring committees be independent of the trial sponsor and leadership?

It has long been a fundamental principle of clinical trials that interim comparative data should be kept confidential, with such data accessible only to a small number of individuals responsible for its analysis and monitoring. The rationale for keeping investigators and sponsors blinded to interim data has been extensively discussed, but the possible conflicts of interest that could arise for the statistician who performs the analysis of the interim data and presents it to a data monitoring committee has received little attention. We describe these potential conflicts, and the advantages and disadvantages of approaches that might be taken to minimize them. We have invited commentary on this issue from several statisticians with substantial experience in clinical trials and interim data monitoring.

Clinical Trials Data Monitoring Committees↗

[Uniform access to clinical data in a distributed system. The radiology example].

PURPOSE: Providing medical reports onwards and ambulatory settings in electronic form can improve the quality of health care delivery. Radiology was chosen as an example to demonstrate how to implement uniform access to clinical data in a hospital. METHOD: Medical professionals at the university hospital in Munich, Grosshadern, have access to all radiological reports of their patients. Web browsers are used as a front end. A centralized administration of users and patients is in place. RESULTS: Centralized access control and patient selection guarantee uniform access to all applicable data via intranet and controls access rights. The high acceptance of this service is reflected by the high number of 150 requests per day. DISCUSSION: Access to radiological reports within the Grosshadern University Clinics was enabled via web browsers in a short time. The high acceptance of the system also proves its easy use. Integration of the system in a centralized user and patient identification system supports the unified access to clinical data.

Computer Security↗

The fine structure of two DNA dodecamers containing the cAMP responsive element sequence and its inverse. Nuclear magnetic resonance and molecular simulation studies.

1H and 31P n.m.r. (nuclear magnetic resonance) spectroscopy have been used in conjunction with molecular simulation to determine the structure of two DNA dodecamers. The first of these, CATGACGTCATG, contains the octameric sequence CRE (cAMP responsive element), while the second is the reversed sequence, GTACTGCAGTAC. Structure determination was based on both NOESY (nuclear Overhauser spectroscopy) derived distances and COSY (correlated spectroscopy) dihedral angle data. Access to the 31P spectra also allowed the epsilon backbone angles to be determined. Considerable care was taken in deriving structural parameters from the n.m.r. data and an excellent level of agreement is obtained with the simulated conformations. Both dodecamers are found to belong to the B-DNA family; however, there is a striking difference between the CRE sequence and its inverse, the former conformation alone showing a strong structural heterogeneity.

Base Sequence↗

Helminth genome analysis: the current status of the filarial and schistosome genome projects. Filarial Genome Project. Schistosome Genome Project.

Genome projects for the parasitic helminths Brugia malayi (a representative filarial nematode) and Schistosoma were initiated in 1995 by the World Health Organization with the ultimate objectives of identifying new vaccine candidates and drug targets and of developing low resolution genome maps. Because no genetic maps are available, and very few genes have been characterized from either parasite group, the first goal of both Initiatives has been to catalogue new genes for future placement on chromosome and physical maps. These genes have been identified by the expressed sequence tag (EST) approach, utilising cDNA libraries constructed from diverse life cycle stages. To date, the Initiatives have deposited over 16,000 Brugia ESTs and nearly 8000 Schistosoma ESTs in Genbank's dbEST database, corresponding to 6000 and over 3600 genes respectively (33% of Brugia's estimated gene compliment, 18-24% of that of Schistosoma). Large fragment, genomic libraries have been constructed in BAC and YAC vectors for studies of genomic organization and for physical and chromosome mapping, and public, hypertext genomic databases have been established to facilitate data access. We present a summary of progress within the helminth genome initiatives and give several examples of important gene discoveries and future applications of these data.

Animals↗

Conceptual development of an information systems framework for improving continuity in epidemiological research.

Lack of continuity is a problem for survey-based epidemiological research. Poor access to experience and inadequate retention of information means new projects seldom build on successful predecessors to the maximum possible extent. We have designed a data management framework which addresses this problem using a well-known information systems approach. Our ideas provide a means of storing data in a manner which reflects the original research concepts. This makes collected data accessible and understandable without reference to the questionnaire, and allows new questionnaires to be designed quickly and easily. Our framework provides a means for recording developmental, conceptual and other supporting information and documentation which is traditionally poorly conserved. We illustrate the components of the framework using a major Australian epidemiological project as a case study. Once the necessary software is developed, our framework will improve organisational memory within individual research units and has the potential to become a valuable support tool for survey-based research.

Australia↗

SNAPPI-DB: a database and API of Structures, iNterfaces and Alignments for Protein-Protein Interactions.

SNAPPI-DB, a high performance database of Structures, iNterfaces and Alignments of Protein-Protein Interactions, and its associated Java Application Programming Interface (API) is described. SNAPPI-DB contains structural data, down to the level of atom co-ordinates, for each structure in the Protein Data Bank (PDB) together with associated data including SCOP, CATH, Pfam, SWISSPROT, InterPro, GO terms, Protein Quaternary Structures (PQS) and secondary structure information. Domain-domain interactions are stored for multiple domain definitions and are classified by their Superfamily/Family pair and interaction interface. Each set of classified domain-domain interactions has an associated multiple structure alignment for each partner. The API facilitates data access via PDB entries, domains and domain-domain interactions. Rapid development, fast database access and the ability to perform advanced queries without the requirement for complex SQL statements are provided via an object oriented database and the Java Data Objects (JDO) API. SNAPPI-DB contains many features which are not available in other databases of structural protein-protein interactions. It has been applied in three studies on the properties of protein-protein interactions and is currently being employed to train a protein-protein interaction predictor and a functional residue predictor. The database, API and manual are available for download at: http://www.compbio.dundee.ac.uk/SNAPPI/downloads.jsp.

Cluster Analysis↗

Mapping clause of Arden Syntax with HL7 and ASTM E 1238-88 standard.

The Arden Syntax is a standard description syntax for modular medical knowledge. The purpose of the Arden Syntax is to allow the construction of medical knowledge bases out of elementary medical logic modules (MLMs) that may be contributed and shared by different institutions. The format of the input data is not defined in the Arden Syntax, but left to the user. Every input and output must be rewritten for the local data access definition before an MLM can be used. It is suggested that by using the Health Level Seven (HL7) interface definition to define the communication and data transfer between the MLMs and the medical data base the shareability of MLMs can be enhanced.

Artificial Intelligence↗

Childhood thermal injuries in New Zealand resulting in death and hospitalization.

Thermal injury is a significant contributor to the overall problem of injury among children. Children are at greater risk of hospitalization due to thermal injury than any other age group, and their fatality rate is second only to those over 60 years of age. This study provides an overview of thermal injury in New Zealand children, age 0-14 years, resulting in death or hospitalization. Eighty-one thermal fatalities were identified from Health Statistical Services (HSS), Department of Health, data accessed for the 10-year period from 1978 to 1987. The records of the Coroners' Court, held by the Justice Department, were also accessed in order to gather additional information about the circumstances of fatal injury in each case. Thermal injury hospital admissions (n = 634) were identified from HSS data for the year 1988. Children were more likely to die in house fires than any other thermal injury event. Most house fires were started by smoking paraphernalia or electrical appliances. Two-thirds of the childhood thermal injury hospitalizations were due to contact with hot water, the most commonly identified source being a hot beverage. Thermal injury rates for New Zealand children are higher than reported overseas. Prevention strategies that have proven effective elsewhere are discussed with recommendations for New Zealand.

Adolescent↗

Pharmacokinetics/Pharmacodynamics and the stages of drug development: role of modeling and simulation.

Pharmacokinetic (PK) and pharmacodynamic (PD) modeling and simulation (M&S) are well-recognized powerful tools that enable effective implementation of the learn-and-confirm paradigm in drug development. The impact of PK/PD M&S on decision making and drug development risk management is dependent on the question being asked and on the availability and quality of data accessible at a particular stage of drug development. For instance, M&S methodologies can be used to capture uncertainty and use the expected variability in PK/PD data generated in preclinical species for projection of the plausible range of clinical dose; clinical trial simulation can be used to forecast the probability of achieving a target response in patients based on information obtained in early phases of development. Framing the right question and capturing the key assumptions are critical components of the "learn-and-confirm" paradigm in the drug development process and are essential to delivering high-value PK/PD M&S results. Selected works of PK/PD modeling and simulation from preclinical to phase III are presented as case examples in this article.

Clinical Trials as Topic↗

High-dose clopidogrel loading in percutaneous coronary intervention.

OBJECTIVE: To review the use of a 600-mg clopidogrel loading dose in patients undergoing percutaneous coronary intervention (PCI). DATA SOURCES: Human clinical trials and platelet studies available through PubMed (1966-March 2005), bibliographies of pertinent articles, and citations supplied by the drug manufacturer were accessed. DATA SYNTHESIS: The administration of a 600-mg loading dose of clopidogrel can decrease the time required for maximum platelet inhibition to 2 hours compared with > or =6 hours achieved with 300 mg. This higher loading dose has been investigated in multiple platelet studies and one observational report. Several randomized controlled trials have used a 600-mg loading dose; however, these studies were not designed to evaluate the efficacy and safety of this loading regimen. To date, only one randomized trial has compared the 600-mg loading dose with a 300-mg loading dose. CONCLUSIONS: When compared with a conventional loading regimen of 300 mg in lower-risk patients, pretreatment with clopidogrel 600 mg was shown to be more effective in reducing periprocedural events and demonstrated similar safety. Studies are needed to clarify the use of a 600-mg loading dose in higher-risk patients, with concomitant glycoprotein IIb/IIIa receptor antagonism, or when administration is delayed until immediately before or after PCI.

Aged↗

MuStaR and other software for locus-specific mutation databases.

As the human genome sequencing project nears completion, there has been a vast increase in the rate at which disease and nondisease associated variant sequences are being sought and detected. This has heightened the need for software with which to accumulate allelic variant (mutation) data, and with which to make the data accessible to the scientific community. Many ad hoc solutions have been developed by those interested in specific genes and diseases, and the creation of central databases which hold data for all genes has provided an alternative repository for some of the locus data. Despite this, few specialised software tools exist for researchers to create their own locus-specific allelic variant databases. This article describes methods available to potential curators, including software systems developed with the sole purpose of generating locus-specific mutation databases. In particular, the authors' own software, MuStaRtrade mark, is described. MuStaRtrade mark allows curators to maintain a database on a laptop computer if desired, while being able to export the data to an automatically generated Website which will run on any cgi compliant Web server. Searching the database and the submission of new mutations are made possible through fill-in Web forms. A number of other software tools which may be of use to curators are also described.

Chromosome Mapping↗

TRANSFAC retrieval program: a network model database of eukaryotic transcription regulating sequences and proteins.

DNA sequences that are involved in the control of gene expression in eukaryotes have been collected in conjunction with the proteins binding to and acting through them (TRANSFAC data set). To make these data accessible, the TRANSFAC retrieval program (TRP) has been developed as a database management system which is based upon the network model. This database model possesses particular advantages for data management of a complex structure. The aim of TRP is to provide an easily handled statistical basis for a computational approach to transcription control.

Amino Acid Sequence↗

Micromolar A and B blood group active trisaccharides abolish human complement haemolytic activity assayed by erythrocytes.

BACKGROUND: At present, there is really no satisfactory treatment of severe haemolytic transfusion reactions involving the ABO system other than the use of steroids that at best are palliative in their effects. In contrast, the use of micromolar concentrations of A or B blood group active trisaccharides that are inexpensive and readily available may prevent lysis by generating soluble immune complexes (ICs) that consume complement. The purpose of this study was to determine the total lytic activity of human serum and to estimate the extent to which trisaccharides can exhaust this capacity. METHODS: We measured complement consumption by (ICs) formed between anti-blood group antibodies and A or B blood group active sugars on erythrocytes (solid phase) or soluble components carrying trisaccharides (fluid phase) in AB serum. A direct complement-mediated lysis (DCL) assay measured the solid-phase reaction and an indirect complement consumption assay (CCA) allowed determination of the fluid-phase reaction. In CCA, the residual lytic activity of AB serum was measured following preincubation with various ICs. RESULTS: Based on over 4000 data points a new mathematical model of complement consumption was formulated. Its predictions deviated by less than 6% in DCL and 9% in CCA when compared with the experimentally accessible data. The new model describes the dynamics of complement consumption including the soluble phase of the reaction. CONCLUSIONS: The mathematical model extrapolation predicts that: (1) in undiluted human serum up to 40% of the physiological erythrocyte concentration could be lysed (when antibodies did not limit lysis); and (2) a 40 microM (or less) concentration of blood group active trisaccharides per patient is sufficient to block the haemolytic complement activity.

ABO Blood-Group System↗

Heterogenous database integration in a physician workstation.

We discuss the integration of a variety of data and information sources in a Physician Workstation (PWS), focusing on the integration of data from DHCP, the Veteran Administration's Distributed Hospital Computer Program. We designed a logically centralized, object-oriented data-schema, used by end users and applications to explore the data accessible through an object-oriented database using a declarative query language. We emphasize the use of procedural abstraction to transparently integrate a variety of information sources into the data schema.

Computer Communication Networks↗

Autism post-mortem neuroinformatic resource: the autism tissue program (ATP) informatics portal.

The Autism Tissue Program (ATP) was established to oversee and manage brain donations related to neurological research in autism. The ATP Informatics Portal (www.atpportal.org) is an integrated data access system based on Oracle technology, developed to provide access for researchers to information on this rare tissue resource. It also permits sorting of existing cases based on donor ante-mortem history as well as agonal states and post-mortem tissue conditions. Phase II of development established administrative tracking of registrants intending to donate, as well as management of tissue requests and the awarding and tracking of tissue. Phase III is the ongoing assimilation of data sets derived from research on a core group of donors with searchable access by investigators.

Autistic Disorder↗

Elevated risk for tobacco use among men who have sex with men is mediated by demographic and psychosocial variables.

Men who have sex with men (MSM) may be more likely to smoke than general population men. Such population comparisons typically do not control for demographic differences and have not tested reasons for MSMs' greater tobacco use. We compared MSM with general population men in data that allowed us to control demographic differences, and hypothesized that MSM would report more tobacco use, due to elevated levels of three psychosocial variables that generally predict tobacco use: depression symptoms, alcohol use, and limited health access. Data were from a 2001 survey of MSM in Chicago (n = 817) and from the 2001 National Health Interview Study (n = 7,783). Significantly more MSM used tobacco, particularly younger MSM. Depression symptoms, alcohol use, and limited health access were more common among MSM and partially accounted for their elevated smoking risk. The lower health access and greater vulnerability of MSM to depression and alcohol use contributed to their higher smoking rate and must be considered in further smoking research and prevention. Younger MSM show very high rates of smoking and are a particular intervention target. Limitations of this cross-sectional study are noted.

Adolescent↗

Information management systems for pharmacogenomics.

The value of high-throughput genomic research is dramatically enhanced by association with key patient data. These data are generally available but of disparate quality and not typically directly associated. A system that could bring these disparate data sources into a common resource connected with functional genomic data would be tremendously advantageous. However, the integration of clinical and accurate interpretation of the generated functional genomic data requires the development of information management systems capable of effectively capturing the data as well as tools to make that data accessible to the laboratory scientist or to the clinician. In this review these challenges and current information technology solutions associated with the management, storage and analysis of high-throughput data are highlighted. It is suggested that the development of a pharmacogenomic data management system which integrates public and proprietary databases, clinical datasets, and data mining tools embedded in a high-performance computing environment should include the following components: parallel processing systems, storage technologies, network technologies, databases and database management systems (DBMS), and application services.

Animals↗