Search results for "TaqMan"
showing 10 items of 35 documents
A TaqMan-based real-time PCR assay for the specific detection and quantification ofLeuconostoc mesenteroidesin meat products
2007
A new real-time PCR procedure was developed for the specific detection and quantification of Leuconostoc mesenteroides in meat products. It is a TaqMan assay based on 23S rRNA gene targeted primers and probe. Specificity was evaluated using purified DNA from 132 strains: 102 lactic acid bacteria (LAB), including 57 reference strains and 46 food isolates, belonging to genus Leuconostoc and related genera, and 30 non-LAB strains. Quantification was linear over at least 5 log units using both serial dilutions of purified DNA and calibrated cell suspensions from Leuconostoc mesenteroides ssp. dextranicum CECT 912T. This assay was able to detect at least five genomic equivalents, using purified …
PCR-based procedures for detection and quantification of Staphylococcus aureus and their application in food.
2006
Aims: To evaluate the specificity of nuc targeted primers for PCR detection of Staphylococcus aureus in different food matrices and to establish a RTQ-PCR procedure suitable for the routine detection and quantification of this pathogen in food. Methods and Results: Specificity of nuc targeted primers (Pri1–Pri2 and the newly designed RTQ-PCR primers) was tested on a total of 157 strains of genetically confirmed identity, including reference and food isolates. PCR detection on artificially inoculated beef samples by DNA extraction using a DNeasy Tissue Kit (Qiagen GmhH, Hilden, Germany) showed a sensitivity value around 103 CFU g−1. The two RTQ-PCR systems, incorporating SYBR-Green I and T…
Development of a TaqMan PCR assay for the identification of the non-native copepod Acartia tonsa, and detection of this species in Norwegian coastal …
2021
Abstract Molecular based assays for detection of species are a powerful tool to supplement morphological methods that may be time and labor intensive. Here we describe a sensitive TaqMan real time polymerase chain reaction assay that specifically detects the presence of Acartia tonsa in mixed plankton samples. The assay is used to find this non-native copepod in samples collected in Norwegian coastal waters.
Quantitative real-time PCR with SYBR Green detection to assess gene duplication in insects: study of gene dosage in Drosophila melanogaster (Diptera)…
2011
Abstract Background The accurate determination of the number of copies of a gene in the genome (gene dosage) is essential for a number of genetic analyses. Quantitative real time PCR (qPCR) with TaqMan detection has shown advantages over traditional Southern-blot and FISH techniques, however the high costs of the required labeled probes is an important limitation of this method. qPCR with SYBR Green I detection is a simple and inexpensive alternative, but it has never been applied to the determination of the copy number of low copy number genes in organisms with high allelic variability (as some insects), where a very small margin of error is essential. Findings We have tested the suitabili…
Genetic polymorphism related to exfoliative glaucoma is also associated with primary open-angle glaucoma risk
2014
Background To investigate the possible association of the rs2165241 polymorphism (C > T) in LOXL1 gene with the risk of primary open-angle glaucoma in a Mediterranean population. Methods The analysis of genetic polymorphisms was performed by standard TaqMan allelic discrimination technique, using a 7900HT Sequence Detection System (Applied Biosystems). Results In a recessive genetic model, the T allele of the rs2165241 polymorphism was significantly associated with the risk of primary open-angle glaucoma (TT vs. CC: odds ratios = 2.19, 95% confidence interval = [1.33–3.62]). After multivariate logistic regression model adjusted by age and weight, the magnitude of the association decreased b…
Expression of genes encoding the calcium signalosome in cellular and transgenic models of Huntington's disease
2013
Huntington's disease (HD) is a hereditary neurodegenerative disease caused by the expansion of a polyglutamine stretch in the huntingtin (HTT) protein and characterized by dysregulated calcium homeostasis. We investigated whether these disturbances are correlated with changes in the mRNA level of the genes that encode proteins involved in calcium homeostasis and signaling (i.e., the calciosome). Using custom-made TaqMan low-density arrays containing probes for 96 genes, we quantified mRNA in the striatum in YAC128 mice, a model of HD, and wildtype mice. HTT mutation caused the increased expression of some components of the calcium signalosome, including calretinin, presenilin 2, and calmyri…
Concordance of assays designed for the quantification of JAK2V617F: a multicenter study
2008
Background Many different techniques have been designed for the quantification of JAK2 V617F allelic burden, sometimes producing discrepant results. Design and Methods JAK2 V617F quantification techniques were compared among 16 centers using 11 assays based on quantitative polymerase chain reaction (with mutation-specific primers or probes, or fluorescent resonance energy transfer/melting curve analysis), allele-specific polymerase chain reaction, conventional sequencing or pyrosequencing. Results A first series of blinded samples (granulocyte DNA, n=29) was analyzed. Seven assays (12 centers) reported values inside the mean±2SD; the mean coefficient of variation was 31%. Sequencing techniq…
Point‐of‐care HCV RNA testing in the setting of DAA therapy: HCV‐FiS (HEpatitis C Virus Fingerstick Study)
2019
HCV-RNA assessment during therapy with Direct-Acting Antiviral (DAA) regimens still relies on assays requiring blood collection and transport to a specialised laboratory, which may compromise linkage to care. GeneXpert-HCV Viral Load (GXHVL) (Cepheid) is a plasma-based assay used at point of care (POC) with a sensitivity of ≤10 IU/mL, and, results available within 2 hours. Fifty-nine consecutive HCV-patients ready for DAAs treatment were enrolled. HCV-RNA was simultaneously tested using Roche TaqMan RT-PCR (venous blood sample) and GXHVL (capillary blood collected by fingerstick), at baseline (BL), week 4 (W4) of therapy, end of therapy (EOT) and week 12 of follow-up (W12FU). Both assays de…
Nation-wide study of the occurrence of Listeria monocytogenes in French soils using culture-based and molecular detection methods
2013
Identifiant HAL : hal-01120618; International audience; Soil is a potential reservoir of human pathogens and a possible source of contamination of animals, crops and water. In order to study the distribution of Listeria monocytogenes in French soils, a real-time PCR TaqMan assay targeting the phosphoribosylpyrophosphate synthetase (prs) gene of L. monocytogenes was developed for the specific detection and quantification of this bacterium within a collection of 1315 soil DNAs originated from the French Soil Quality Monitoring Network. The prs real-time PCR TaqMan assay was specific for L. monocytogenes and could quantify accurately down to 104L. monocytogenes per gram of dry soil. Among the …
Application of fnbA gene as new target for the species-specific and quantitative detection of Staphylococcus aureus directly from lower respiratory t…
2013
Staphylococcus aureus is a significant cause of hospital-acquired pneumonia (HAP), particularly in mechanically ventilated patients. We used the fibronectin-binding protein A gene (fnbA) for the species-specific and quantitative detection of S. aureus directly from lower respiratory tract (LRT) specimens by a Taq Man real time PCR. For this reason, a total of 269 lower respiratory tract (LRT) specimens collected from patients with hospital-acquired pneumonia were assayed. Amplification of fnbA in serial dilutions ranged from 10(9) CFU/ ml to 10(2) CFU/ml. Standard curve of triplicate every dilution had slope 3.34±0.1 and R2>0.99 with SD 0.1. Based on these data, the sensitivity and specif…