Fast and sensitive DNA analysis using changes in the FRET signals of molecular beacons in a PDMS microfluidic channel

2007 ◽  
Vol 387 (8) ◽  
pp. 2609-2615 ◽  
Author(s):  
Jaehyun Jung ◽  
Lingxin Chen ◽  
Sangyup Lee ◽  
Sungyong Kim ◽  
Gi Hun Seong ◽  
...  
Keyword(s):  
Dna Analysis ◽  
Microfluidic Channel ◽  
Molecular Beacons

scholarly journals Nanowires and molecular beacons for DNA analysis

2007 ◽  
Vol 79 (5) ◽  
pp. 1789-1789
Author(s):  
Thomas Hayden
Keyword(s):  
Dna Analysis ◽  
Molecular Beacons

scholarly journals A Disposable DNA Analysis Chip with a Powerless Actuator

2022 ◽  
Author(s):  
Kyungsup Han ◽  
Insup Kim ◽  
Wei Xuan Chan ◽  
Sanglae Kim ◽  
Jeong-Hwan Kim ◽  
...  
Keyword(s):  
Dna Extraction ◽  
Dna Analysis ◽  
Exothermic Reaction ◽  
Microfluidic Channel ◽  
Dna Amplification ◽  
Extraction Process ◽  
Gas Production ◽  
Diagnostic Process ◽  
Hydration Reaction ◽  
Operational Error

Abstract A non-instrumented, single-use, affordable, and fully- yet safely-disposable DNA analysis system for Point Of Care (POC) diagnostic process has been proposed by integrating (1) a hydration-reactive mixture for a portable heating element as a powerless actuator, (2) commercially available optical adhesive films as valves, and (3) an exothermic reaction-based recombinant polymerase amplification (RPA) process for non-instrumented DNA amplification. The operational error tolerance of the adhesive valves was evaluated by gas production and long-lasting ability, and the amplification performance of the RPA device was validated by gel electrophoresis. Finally, a DNA analysis device was fabricated and tested based on a hydration reaction with a DNA extraction microfluidic channel and an exothermic reaction-based RPA device. In the DNA extraction process, dimethyl adipimidate (DMA) solution was used to eliminate some required injection steps from the extraction process. The integrated system's functionality was successfully demonstrated, and the suggested system could become a foundation for the ultimate total solution for POC DNA analysis.

Photo-tethered molecular beacons for superior light-induction

2021 ◽  
Author(s):  
Robin Klimek ◽  
Mantian Wang ◽  
Vivien R. McKenney ◽  
Erin M. Schuman ◽  
Alexander Heckel
Keyword(s):  
Molecular Beacons ◽  
Light Induction ◽  
In Cells

Photolabile circularization of molecular beacons via backbone phosphates leads to superior probes to study spatiotemporal aspects of RNA in cells.

“Pseudo Homozygous” Activated Protein C Resistance due to Double Heterozygous Factor V Defects (Factor V Leiden Mutation and Type I Quantitative Factor V Defect) Associated with Thrombosis: Report of Two Cases Belonging to Two Unrelated Kindreds

1996 ◽  
Vol 75 (03) ◽  
pp. 422-426 ◽  
Author(s):  
Paolo Simioni ◽  
Alberta Scudeller ◽  
Paolo Radossi ◽  
Sabrina Gavasso ◽  
Bruno Girolami ◽  
...  
Keyword(s):  
Protein C ◽  
Dna Analysis ◽  
Activated Protein C ◽  
Factor V Leiden ◽  
Type I ◽  
Factor V ◽  
Factor V Leiden Mutation ◽  
Thrombotic Risk ◽  
Apc Resistance ◽  
Quantitative Factor

SummaryTwo unrelated patients belonging to two Italian kindreds with a history of thrombotic manifestations were found to have a double heterozygous defect of factor V (F. V), namely type I quantitative F. V defect and F. V Leiden mutation. Although DNA analysis confirmed the presence of a heterozygous F. V Leiden mutation, the measurement of the responsiveness of patients plasma to addition of activated protein C (APC) gave results similar to those found in homozygous defects. It has been recently reported in a preliminary form that the coinheritance of heterozygous F. V Leiden mutation and type I quantitative F. V deficiency in three individuals belonging to the same family resulted in the so-called pseudo homozygous APC resistance with APC sensitivity ratio (APC-SR) typical of homozygous F. V Leiden mutation. In this study we report two new cases of pseudo homozygous APC resistance. Both patients experienced thrombotic manifestations. It is likely that the absence of normal F. V, instead of protecting from thrombotic risk due to heterozygous F. V Leiden mutation, increased the predisposition to thrombosis since the patients became, in fact, pseudo-homozygotes for APC resistance. DNA-analysis is the only way to genotype a patient and is strongly recommended to confirm a diagnosis of homozygous F. V Leiden mutation also in patients with the lowest values of APC-SR. It is to be hoped that no patient gets a diagnosis of homozygous F. V Leiden mutation based on the APC-resi-stance test, especially when the basal clotting tests, i.e., PT and aPTT; are borderline or slightly prolonged.

Abnormal Processing of the Glycoprotein IIb Transcript due to a Nonsense Mutation in Exon 17 Associated with Glanzmann’s Thrombasthenia

1995 ◽  
Vol 73 (05) ◽  
pp. 756-762 ◽  
Author(s):  
Yoshiaki Tomiyama ◽  
Hirokazu Kashiwagi ◽  
Satoru Kosugi ◽  
Masamichi Shiraga ◽  
Yoshio Kanayama ◽  
...  
Keyword(s):  
Dna Analysis ◽  
Molecular Genetic ◽  
Genetic Defect ◽  
Nucleotide Sequence Analysis ◽  
Type I ◽  
Normal Amount ◽  
Immunoblot Assay ◽  
Glanzmann’S Thrombasthenia ◽  
Glanzmann's Thrombasthenia ◽  
Pcr Products

SummaryWe analyzed the molecular genetic defect responsible for type I Glanzmann’s thrombasthenia in a Japanese patient. In an immunoblot assay using polyclonal anti-GPIIb-IIIa antibodies, some GPIIIa (15% of normal amount) could be detected in the patient’s platelets, whereas GPIIb could not (<2% of normal amount). Nucleotide sequence analysis of platelet GPIIb mRNA-derived polymerase chain reaction (PCR) products revealed that patient’s GPIIb cDNA had a 75-bp deletion in the 3’ boundary of exon 17 resulting in an in-frame deletion of 25 amino acids. DNA analysis and family study revealed that the patient was a compound heterozygote of two GPIIb gene defects. One allele derived from her father was not expressed in platelets, and the other allele derived from her mother had a 9644C → T mutation which was located at the position -3 of the splice donor junction of exon 17 and resulted in a termination codon (TGA). Moreover, quantitative analysis demonstrated that the amount of the abnormal GPIIb transcript in the patient’s platelets was markedly reduced. Thus, the C → T mutation resulting in the abnormal splicing of GPIIb transcript and the reduction in its amount is responsible for Glanzmann’s thrombasthenia.

Molecular Characterization of a Type I Quantitative Factor V Deficiency in a Thrombosis Patient that Is “Pseudo Homozygous” for Activated Protein C Resistance

1997 ◽  
Vol 77 (02) ◽  
pp. 252-257 ◽  
Author(s):  
Joan F Guasch ◽  
Ruud P M Lensen ◽  
Rogier M Bertina
Keyword(s):  
Protein C ◽  
Dna Analysis ◽  
Activated Protein C ◽  
Type I ◽  
Factor V ◽  
Sequencing Analysis ◽  
Apc Resistance ◽  
Quantitative Factor ◽  
Factor V Deficiency ◽  
Fv Leiden

SummaryResistance to activated protein C (APC), which is associated with the FV Leiden mutation in the large majority of the cases, is the most common genetic risk factor for thrombosis. Several laboratory tests have been developed to detect the APC-resistance phenotype. The result of the APC-resistance test (APC-sensitivity ratio, APC-SR) usually correlates well with the FV Leiden genotype, but recently some discrepancies have been reported. Some thrombosis patients that are heterozygous for FV Leiden show an APC-SR usually found only in homozygotes for the defect. Some of those patients proved to be compound heterozygotes for the FV Leiden mutation and for a type I quantitative factor V deficiency. We have investigated a thrombosis patient characterized by an APC-SR that would predict homozygosity for FV Leiden. DNA analysis showed that he was heterozygous for the mutation. Sequencing analysis of genomic DNA revealed that the patient also is heterozygous for a G5509→A substitution in exon 16 of the factor V gene. This mutation interferes with the correct splicing of intron 16 and leads to the presence of a null allele, which corresponds to the “non-FV Leiden” allele. The conjunction of these two defects in the patient apparently leads to the same phenotype as observed in homozygotes for the FV Leiden mutation.

Screening for the FV: Q506 Mutation – Evaluation of Thirteen Plasma-based Methods for their Diagnostic Efficacy in Comparison with DNA Analysis

1997 ◽  
Vol 77 (03) ◽  
pp. 436-439 ◽  
Author(s):  
Armando Tripodi ◽  
Barbara Negri ◽  
Rogier M Bertina ◽  
Pier Mannuccio Mannucci
Keyword(s):  
Venous Thrombosis ◽  
Large Scale ◽  
Dna Analysis ◽  
Genetic Defect ◽  
Laboratory Diagnosis ◽  
Economic Benefits ◽  
Factor V ◽  
Factor X ◽  
Diagnostic Efficacy ◽  
Dna Test

SummaryThe factor V (FV) mutation Q506 that causes resistance to activated protein C (APC) is the genetic defect associated most frequently with venous thrombosis. The laboratory diagnosis can be made by DNA analysis or by clotting tests that measure the degree of prolongation of plasma clotting time upon addition of APC. Home-made and commercial methods are available but no comparative evaluation of their diagnostic efficacy has so far been reported. Eighty frozen coded plasma samples from carriers and non-carriers of the FV: Q506 mutation, diagnosed by DNA analysis, were sent to 8 experienced laboratories that were asked to analyze these samples in blind with their own APC resistance tests. The APTT methods were highly variable in their capacity to discriminate between carriers and non-carriers but this capacity increased dramatically when samples were diluted with FV-deficient plasma before analysis, bringing the sensitivity and specificity of these tests to 100%. The best discrimination was obtained with methods in which fibrin formation is triggered by the addition of activated factor X or Russell viper venom. In conclusion, this study provides evidence that some coagulation tests are able to distinguish carriers of the FV: Q506 mutation from non-carriers as well as the DNA test. They are inexpensive and easy to perform. Their use in large-scale clinical trials should be of help to determine the medical and economic benefits of screening healthy individuals for the mutation before they are exposed to such risk factors for venous thrombosis as surgery, pregnancy and oral contraceptives.

Sign in / Sign up

Export Citation Format

Share Document