Search results for "AMPLIFICATION"

The Determination of Methylmercury in Real Samples Using Organically Capped Mesoporous Inorganic Materials Capable of Signal Amplification

2009

Concentration dependent effects of commonly used pesticides on activation versus inhibition of the quince (Cydonia Oblonga) polyphenol oxidase

2009

Polyphenol oxidase (PPO) catalyzes the oxidation of o-diphenols to their respective quinones which undergo autopolymerization and form dark pigments. The interaction of PPO with various substrates and effectors remains the focus of intensive investigations due to the enzyme's key role in pigments biosynthesis including animal melanogenesis and fruit/fungi enzymatic browning. In this study, the effect of a range of commonly used pesticides on the enzyme activity has been evaluated using the purified quince (Cydonia oblonga Miller) PPO. The biochemical analysis showed that, in the presence of high pesticide concentrations, the enzyme was competitively inhibited, particularly with benomyl, car…

A bicistronic vector backbone for rapid seamless cloning and chimerization of αβT-cell receptor sequences.

2020

To facilitate preclinical testing of T-cell receptors (TCRs) derived from tumor-reactive T-cell clones it is necessary to develop convenient and rapid cloning strategies for the generation of TCR expression constructs. Herein, we describe a pDONR™221 vector backbone allowing to generate Gateway™ compatible entry clones encoding optimized bicistronic αβTCR constructs. It harbors P2A-linked TCR constant regions and head-to-head-oriented recognition sites of the Type IIS restriction enzymes BsmBI and BsaI for seamless cloning of the TCRα and TCRβ V(D)J regions, respectively. Additional well-established TCR optimizations were incorporated to enhance TCR functionality. This included replacing of…

Reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) as a user-friendly system to detect SARS-CoV-2 infection: a multicentric study

2021

Although reverse transcriptase quantitative PCR remains the gold standard to perform viral detection, reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) is already used to perform diagnosis of various infections. This work reports the results of a multicentric study performed in Sicily to evaluate the diagnostic power of an RT-LAMP kit for the diagnosis of SARS-CoV-2 infection on a total of 551 samples collected in January and February 2021, revealing sensitivity, specificity, accuracy, positive and negative predictive values ≥95%. Our results suggest the potential employment of this kit as a screening test to be used where fast and reliable results are demanded without …

Nalidixic acid-resistant V79 cells with reduced DNA topoisomerase II activity and amplification prone phenotype

1992

Spontaneously nalidixic acid-resistant lines (NAr lines) were selected from a V79 Chinese hamster cell line and phenotypically characterized. NAr lines showed an increased doubling time, a higher number of spontaneous SCE, and more interestingly, decreased DNA topoisomerase II activity. These lines were also cross-resistant to the eukaryotic topoisomerase II inhibitors etoposide and adriamycin, but showed the same level of sensitivity as the parental line to the DNA topoisomerase I inhibitor camptothecin. NAr lines were cross-resistant to other drugs, such as PALA, MTX and MPA, resistance to which has been shown to arise by amplification of the target genes. This last feature, together with…

Influence of Neuroblastoma Stage on Serum-Based Detection of MYCN Amplification

2009

BACKGROUND: MYCN oncogene amplification has been defined as the most important prognostic factor for neuroblastoma (NB), the most common solid extracranial neoplasm in children. High copy numbers are strongly associated with rapid tumor progression and poor outcome, independently of tumor stage or patient age, and this has become an important factor in treatment stratification. PROCEDURE: By real-time quantitative PCR analysis, we evaluated the clinical relevance of circulating MYCN DNA of 267 patients with locoregional or metastatic NB in children less than 18 months of age. RESULTS: For patients in this age group with INSS stage 4 or 4S NB and stage 3 patients, serum-based determination o…

Don't change a winning horse

2005

IntroductionThere is surprising excitement about the adequacy andfuture of the somatoform disorders (SFDs) as a circum-scribed diagnostic group [1–4]. Some authors wish to takethe forthcoming fifth revision of the Diagnostic andStatistical Manual (DSM) as a welcome occasion to removean unloved diagnostic term. However, eliminating the SFDswould devaluate the progress of research and clinicalpractice made during the past 25 years. It would lead toinsecurity and confusion in an interdisciplinary field whereclear terminology and common understanding is of highvalue. This contribution attempts to summarize some of themajor reasons why DSM-V should continue with the SFDs.Some suggestions will be…

Quantum algorithms for search with wildcards and combinatorial group testing

2012

We consider two combinatorial problems. The first we call "search with wildcards": given an unknown n-bit string x, and the ability to check whether any subset of the bits of x is equal to a provided query string, the goal is to output x. We give a nearly optimal O(sqrt(n) log n) quantum query algorithm for search with wildcards, beating the classical lower bound of Omega(n) queries. Rather than using amplitude amplification or a quantum walk, our algorithm is ultimately based on the solution to a state discrimination problem. The second problem we consider is combinatorial group testing, which is the task of identifying a subset of at most k special items out of a set of n items, given the…

Systematics of strong nuclear amplification of gluon saturation from exclusive vector meson production in high energy electron–nucleus collisions

2017

We show that gluon saturation gives rise to a strong modification of the scaling in both the nuclear mass number $A$ and the virtuality $Q^2$ of the vector meson production cross-section in exclusive deep-inelastic scattering off nuclei. We present qualitative analytic expressions for how the scaling exponents are modified as well as quantitative predictions that can be tested at an Electron-Ion Collider.

Correcting for Potential Barriers in Quantum Walk Search

2015

A randomly walking quantum particle searches in Grover's $\Theta(\sqrt{N})$ iterations for a marked vertex on the complete graph of $N$ vertices by repeatedly querying an oracle that flips the amplitude at the marked vertex, scattering by a "coin" flip, and hopping. Physically, however, potential energy barriers can hinder the hop and cause the search to fail, even when the amplitude of not hopping decreases with $N$. We correct for these errors by interpreting the quantum walk search as an amplitude amplification algorithm and modifying the phases applied by the coin flip and oracle such that the amplification recovers the $\Theta(\sqrt{N})$ runtime.