Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “high throughput”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources

Data analysis of high-throughput screening results: application of multidomain clustering to the NCI anti-HIV data set.

The routine use of high-throughput screening (HTS) systems in the drug discovery process has resulted in an increasing need for fast, reliable analysis of massive amounts of data. A new automated multidomain clustering method that thoroughly analyzes screening data sets is used to examine both the active and the inactive compounds in a well-known, publicly available data set based on primary screening. Large and small compound sets that defined both chemical families and potential pharmacophore points were discovered. The detection of structure-activity relationships (SAR), aided by the unique classification method, is described in this article.

Algorithms↗

In vivo functional genomics of Pseudomonas aeruginosa for high-throughput screening of new virulence factors and antibacterial targets.

Pseudomonas aeruginosa is a model for studying opportunistic pathogens that are highly resistant to most classes of antibiotics and cause chronic pulmonary infections. We have developed and adapted a multiplex polymerase chain reaction-based signature-tagged mutagenesis (STM) for high-throughput screening of a collection of 7968 P. aeruginosa mutants in a rat model of chronic respiratory infection. After three rounds of screening, a total of 214 mutants, representing transposition events into 148 open reading frames, were shown to be attenuated in lung infection and were retained for further analysis. As proof of concept supporting this technology, we identified 11 insertions in typical virulence genes such as those coding for pili implicated in motility, attachment and swarming, alginate synthesis and its expression, a mucus transcription regulator, extracellular enzymes such as alkaline protease, esterase and amino peptidase, a rhamnosyl surfactant transferase and a lipopolysaccharide glycosyl transferase. Detailed analysis of the 148 STM mutants, including seven auxotrophs, revealed insertions in 21 of the 26 known gene classes used to characterize sequenced bacterial genomes. We noted that at least 46% of STM mutants identified had insertions in hypothetical proteins or proteins of unknown function and that approximately 40% of all STM mutants had insertions in surface proteins including the outer membrane, the periplasm and the inner membrane. Interestingly, 11 STM mutants attenuated for lung infection were also identified in microarray and transcriptome for quorum sensing and mucoidy production. The remaining 130 mutants were systematically analysed for their capability to express fully known virulence factors. In addition, testing the ability of these mutants to infect alternative model host Drosophila melanogaster revealed 36 STM mutants defective in protease, twitching motility, swimming and swarming. Finally, we identified many genes, the activity of which in respiratory infection was not fully appreciated.

Alkaline Phosphatase↗

Multiplex mRNA assay using electrophoretic tags for high-throughput gene expression analysis.

We describe a novel multiplexing technology using a library of small fluorescent molecules, termed eTag molecules, to code and quantify mRNA targets. eTag molecules, which have the same fluorometric property, but distinct charge-to-mass ratios possess pre-defined electrophoretic characteristics and can be resolved using capillary electrophoresis. Coupled with primary Invader mRNA assay, eTag molecules were applied to simultaneously quantify up to 44 mRNA targets. This multiplexing approach was validated by examining a panel of inflammation responsive genes in human umbilical vein endothelial cells stimulated with inflammatory cytokine interleukin 1beta. The laser-induced fluorescence detection and electrokinetic sample injection process in capillary electrophoresis allows sensitive quantification of thousands of copies of mRNA molecules in a reaction. The assay is precise, as evaluated by measuring qualified Z' factor, a dimensionless and simple characteristic for applications in high-throughput screening using mRNA assays. Our data demonstrate the synergy between the multiplexing capability of eTag molecules by sensitive capillary electrophoresis detection and the isothermal linear amplification characteristics of the Invader assay. eTag multiplex mRNA assay presents a unique platform for sensitive, high sample throughput and multiplex gene expression analysis.

Cells, Cultured↗

Toward high-throughput drug screening using mass spectrometry.

A critical overview on the potential of mass spectrometry-based methods regarding high-throughput screening analysis is presented. Within this scope, screening procedures will be discussed for simultaneous detection of several drug classes relevant to clinical and forensic toxicology or doping control in urine or blood using gas chromatography-mass spectrometry or liquid chromatography-mass spectrometry.

Drug Evaluation, Preclinical↗

A high-throughput MS-PCR method on MADGE gels for ANG II type-1 receptor A1166C polymorphism.

We have developed a highly accurate, low-cost, single-step, mutagenically separated polymerase chain reaction (MS-PCR) method for the determination of angiotensin II type-1 receptor (AT(1)) A1166C gene polymorphism. The genotypes are determined using the microtiter array diagonal gel electrophoresis (MADGE) system. We have compared the MS-PCR method with allele-specific oligonucleotide hybridization and Dde I digestion techniques for determining the AT(1) A1166C genotype. The combination of MS-PCR and MADGE serves as a model for high-throughput single-nucleotide polymorphism genotyping in large population studies.

Alleles↗

High-throughput screening of corticosteroids and basic drugs in horse urine by liquid chromatography-tandem mass spectrometry.

This paper describes two high-throughput liquid chromatography-tandem mass spectrometry (LC-MS-MS) methods for the screening of two important classes of drugs in equine sports, namely corticosteroids and basic drugs, at low ppb levels in horse urine. The method utilized a high efficiency reversed-phase LC column (3.3 cm L x 2.1 mm i.d. with 3 microm particles) to provide fast turnaround times. The overall turnaround time for the corticosteroid screen was 5 min and that for the basic drug screen was 8 min, inclusive of post-run and equilibration times. Method specificity was assessed by analysing a total of 35 negative post-race horse urine samples. No interference from the matrices at the expected retention times of the targeted masses was observed. Inter-day precision for the screening of 19 corticosteroids and 48 basic drugs were evaluated by replicate analyses (n = 10) of a spiked sample on 4 consecutive days. The results demonstrated that both methods have acceptable precision to be used on a routine basis. The performance of these two methods on real samples was demonstrated by their applications to drug administration and positive post-race urine samples.

Adrenal Cortex Hormones↗

High-performance liquid chromatographic-electrospray ionization mass spectrometric analyses for the integration of natural products with modern high-throughput screening.

Within the pharmaceutical industry, significant resources have been applied to the identification of new drug compound leads through the use of high-throughput screening (HTS). To meet the demand for rapid analytical characterization of biologically active samples identified by HTS, the technique of high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) has been utilized, and the application of this technique specifically for the integration of natural product sample mixtures into modern HTS is reviewed. The high resolution provided by reversed-phase HPLC coupled with the gentle and relatively universal ionization facilitated by the electrospray process has had significant impact upon a variety of procedures associated with the HTS of natural products, including extract sample diversity evaluation, dereplication, structure elucidation, preparative isolation, and affinity-based biological activity evaluation.

Chemistry, Pharmaceutical↗

BABELOMICS: a suite of web tools for functional annotation and analysis of groups of genes in high-throughput experiments.

We present Babelomics, a complete suite of web tools for the functional analysis of groups of genes in high-throughput experiments, which includes the use of information on Gene Ontology terms, interpro motifs, KEGG pathways, Swiss-Prot keywords, analysis of predicted transcription factor binding sites, chromosomal positions and presence in tissues with determined histological characteristics, through five integrated modules: FatiGO (fast assignment and transference of information), FatiWise, transcription factor association test, GenomeGO and tissues mining tool, respectively. Additionally, another module, FatiScan, provides a new procedure that integrates biological information in combination with experimental results in order to find groups of genes with modest but coordinate significant differential behaviour. FatiScan is highly sensitive and is capable of finding significant asymmetries in the distribution of genes of common function across a list of ordered genes even if these asymmetries were not extreme. The strong multiple-testing nature of the contrasts made by the tools is taken into account. All the tools are integrated in the gene expression analysis package GEPAS. Babelomics is the natural evolution of our tool FatiGO (which analysed almost 22,000 experiments during the last year) to include more sources on information and new modes of using it. Babelomics can be found at http://www.babelomics.org.

Binding Sites↗

High-throughput AFLP analysis using infrared dye-labeled primers and an automated DNA sequencer.

Amplified fragment length polymorphism (AFLP) analysis is currently the most powerful and efficient technique for the generation of large numbers of anonymous DNA markers in plant and animal genomes. We have developed a protocol for high-throughput AFLP analysis that allows up to 70,000 polymorphic marker genotype determinations per week on a single automated DNA sequencer. This throughput is based on multiplexed PCR amplification of AFLP fragments using two different infrared dyelabeled primer combinations. The multiplexed AFLPs are resolved on a two-dye, model 4200 LI-COR automated DNA sequencer, and the digital images are scored using semi-automated scoring software specifically designed for complex AFLP banding patterns (AFLP-Quantar). Throughput is enhanced by using high-quality genomic DNA templates obtained by a 96-well DNA isolation procedure.

Electrophoresis↗

High-throughput single nucleotide polymorphism typing by fluorescent single-strand conformation polymorphism analysis with capillary electrophoresis.

In this study, we performed high-throughput and precise single nucleotide polymorphism (SNP) typing by fluorescent capillary electrophoresis single-strand conformation polymorphism (CE-SSCP) analysis. A system composed of a multicapillary DNA analyzer, a newly developed sieving matrix, four different colors of fluorescent labels, and a multiplex polymerase chain reaction (PCR) enabled low-cost and highly reliable SNP typing. Moreover, this system enabled the estimation of SNP allele frequencies using pooled DNA samples, which should be beneficial for large-scale association studies. Thus, fluorescent CE-SSCP analysis is a useful method for large-scale SNP typing.

DNA Fingerprinting↗

A high-throughput method for screening of rapamycin-producing strains of Streptomyces hygroscopicus by cultivation in 96-well microtiter plates.

A novel high-throughput cultivation method was developed to rapidly screen large numbers of rapamycin-producing mutants of Streptomyces hygroscopicus by duplicate culturing of isolates on the surfaces of agar-solidified 96 wells in microtiter plates. One copy of the cultures was used for the rapamycin bioassay and the other identical copy, representing potentially high yielding strains, was preserved for further study. By integrating 96-well solid cultivation and the bioassay, we screened more than 7000 isolates and found 10 high-yielding strains. From these, one mutant produced 420 mug rapamycin/ml, which was double the yield of parent strain used in the submerged fermentation process.

Agar↗

Correlation of high-throughput pregnane X receptor (PXR) transactivation and binding assays.

Pregnane X receptor (PXR) transactivation and binding assays have been developed into high-throughput assays, which are robust and reproducible (Z' > 0.5). For most compounds, there was a good correlation between the results of the transactivation and binding assays. EC(50) values of compounds in the transactivation assay correlated reasonably well with their IC(50) values in the binding assay. However, there were discrepancies with some compounds showing high binding affinity in the binding assay translated into low transactivation. The most likely cause for these discrepancies was an agonist-dependent relationship between binding affinity and transactivation response. In general, compounds that bound to human PXR and transactivated PXR tended to be large hydrophobic molecules.

Cells, Cultured↗

High-throughput biological sample analysis using on-line turbulent flow extraction combined with monolithic column liquid chromatography/tandem mass spectrometry.

A high-throughput liquid chromatography/tandem mass spectrometry (LC/MS/MS) method, which combines on-line sample extraction through turbulent flow chromatography with a monolithic column separation, has been developed for direct injection analysis of drugs and metabolites in human plasma samples. By coupling a monolithic column into the system as the analytical column, the method enables running 'dual-column' extraction and chromatography at higher flow rates, thus significantly reducing the time required for the transfer and mixing of extracted fraction onto the separation column as well as the time for gradient separation. A strategy of assessing and reducing the matrix suppression effect on the on-line extraction LC/MS/MS has also been discussed. Experiments for evaluating the resolution, peak shape, sensitivity, speed, and matrix effect were conducted with dextromethorphan and its metabolite dextrorphan as model compounds in human plasma matrix. It was demonstrated that the total run time for this assay with a baseline separation of two analytes is less than 1.5 min.

Analgesics, Opioid↗

Design strategies for multielectrode arrays applicable for high-throughput impedance spectroscopy on novel gas sensor materials.

This paper reports the first design and fabrication of a 64 multielectrode array for high-throughput impedance spectroscopy. The purpose of this work is the development of a measurement system for the discovery and improvement of sensor materials using combinatorial methods. An array of interdigital capacitors (IDC) screen-printed onto a high-temperature-resistant Al(2)O(3) substrate is determined to be the optimal test plate. The electrode layout, and therefore also the idle capacity, is determined by specific requirements. Calculation of the idle capacity of the IDC as a function of the electrode width and distance allows adjustment and thus optimization of the array. Parasitic effects caused by the leads and contacts are compensated by a software-aided calibration. Apart from the use of the substrates for discovery of new sensor materials, the presented electrode array is also suitable for electrocatalytic applications as well as impedance spectroscopic studies of semiconductors and dielectrics.

Journal Article↗

Sample preparation for high throughput accurate mass analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

An automated sample preparation for high throughput accurate mass determinations by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been developed. Sample preparation was performed with an automated workstation and automated mass analyses were performed with a commercial MALDI-TOF mass spectrometer. The method was tested with a 41-sample library. MALDI-TOFMS was found to give the needed sensitivity, accurate mass measurement, and soft ionization necessary for structure confirmation, even of mixtures. A mass accuracy of 5 ppm or less was obtained in over 80% of known compound measurements. A mass accuracy better than 10 ppm was obtained for all measurements of known compounds. Analyses of parallel synthesis products resulted in 77% of the measurements with a mass accuracy of 5 ppm or better.

Automation↗

PRISM: a data management system for high-throughput proteomics.

Advanced proteomic research efforts involving areas such as systems biology or biomarker discovery are enabled by the use of high level informatics tools that allow the effective analysis of large quantities of differing types of data originating from various studies. Performing such analyses on a large scale is not feasible without a computational platform that performs data processing and management tasks. Such a platform must be able to provide high-throughput operation while having sufficient flexibility to accommodate evolving data analysis tools and methodologies. The Proteomics Research Information Storage and Management system (PRISM) provides a platform that serves the needs of the accurate mass and time tag approach developed at Pacific Northwest National Laboratory. PRISM incorporates a diverse set of analysis tools and allows a wide range of operations to be incorporated by using a state machine that is accessible to independent, distributed computational nodes. The system has scaled well as data volume has increased over several years, while allowing adaptability for incorporating new and improved data analysis tools for more effective proteomics research.

Chromatography, Liquid↗

A high-throughput assay format for determination of nitrate reductase and nitrite reductase enzyme activities.

The authors describe a microplate-based high-throughput procedure for rapid assay of the enzyme activities of nitrate reductase and nitrite reductase, using extremely small volumes of reagents. The new procedure offers the advantages of rapidity, small sample size-nanoliter volumes, low cost, and a dramatic increase in the throughput sample number that can be analyzed simultaneously. Additional advantages can be accessed by using microplate reader application software packages that permit assigning a group type to the wells, recording of the data on exportable data files and exercising the option of using the kinetic or endpoint reading modes. The assay can also be used independently for detecting nitrite residues/contamination in environmental/food samples.

Candida↗

Genome-wide high-throughput screens in functional genomics.

The availability of complete genome sequences from many organisms has yielded the ability to perform high-throughput, genome-wide screens of gene function. Within the past year, rapid advances have been made towards this goal in many major model systems, including yeast, worms, flies, and mammals. Yeast genome-wide screens have taken advantage of libraries of deletion strains, but RNA-interference has been used in other organisms to knockdown gene function. Examples of recent large-scale functional genetic screens include drug-target identification in yeast, regulators of fat accumulation in worms, growth and viability in flies, and proteasome-mediated degradation in mammalian cells. Within the next five years, such screens are likely to lead to annotation of function of most genes across multiple organisms. Integration of such data with other genomic approaches will extend our understanding of cellular networks.

Animals↗