CE with electrochemical detection for investigation of label-free recognition of amino acid amides by guanine-rich DNA aptamers

In this work, we report a simple and effective investigation into adaptive interactions between guanine-rich DNA aptamers and amino acid amides by CE with electrochemical (EC) detection. Argininamide (Arm) and tyrosinamide (Tym) were chosen as model molecules. On a copper electrode, Arm generated a good EC signal in 60 mM NaOH at 0.7 V (vs Ag/ AgCl), while Tym. was detected well on a platinum electrode at 1. 3 V in 20 mM phosphate of pH 7.0. Based on their EC properties, the ligands themselves were used as indicators for the adaptive interactions investigated by CE-EC, making any step of labeling and/or modification of aptamers with indicators exempted. Hydrophilic ionic liquid was used as an additive in running buffer of CE to improve the sensitivity of Arm detection, whereas the additive was not used for Tym. detection due to its negative effect. Two guanine-rich DNA aptamers were used for molecular recognition of Arm and Tym. When the aptamers were incubated with ligands, they bound the model molecules with high affinity and specificity, reflected by obvious decreases in the signals of ligands but no changes in those of the control molecules. However, the ligands were hardly affected by the control ssDNAs after incubation. The results revealed the specific recognition of Arm and Tym. by the aptamers.

Funneled landscape leads to robustness of cellular networks: MAPK signal transduction

We uncover the underlying potential energy landscape for a cellular network. We find that the potential energy landscape of the mitogen-activated protein-kinase signal transduction network is funneled toward the global minimum. The funneled landscape is quite robust against random perturbations. This naturally explains robustness from a physical point of view. The ratio of slope versus roughness of the landscape becomes a quantitative measure of robustness of the network. Funneled landscape is a realization of the Darwinian principle of natural selection at the cellular network level. It provides an optimal criterion for network connections and design. Our approach is general and can be applied to other cellular networks.

Determination of ethenzamide and acetoaminophen in quaternary powdered samples by near infrared spectroscopy and searching combination moving window partial least squares algorithm: effects of spectral resolution and signal-to-noise ratio

The present study reports an application of the searching combination moving window partial least squares (SCMWPLS) algorithm to the determination of ethenzamide and acetoaminophen in quaternary powdered samples by near infrared (NIR) spectroscopy. Another purpose of the study was to examine the instrumentation effects of spectral resolution and signal-to-noise ratio of the Buchi NIRLab N-200 FT-NIR spectrometer equipped with an InGaAs detector. The informative spectral intervals of NIR spectra of a series of quaternary powdered mixture samples were first located for ethenzamide and acetoaminophen by use of moving window partial least squares regression (MWPLSR). Then, these located spectral intervals were further optimised by SCMWPLS for subsequent partial least squares (PLS) model development. The improved results are attributed to both the less complex PLS models and to higher accuracy of predicted concentrations of ethenzamide and acetoaminophen in the optimised informative spectral intervals that are featured by NIR bands. At the same time, SCMWPLS is also demonstrated as a viable route for wavelength selection.

Discrete wavelets transform for signal denoising in capillary electrophoresis with electrochemiluminescence detection

Discrete wavelets transform (DWT). was applied to noise on removal capillary electrophoresis-electrochemiluminescence (CE-ECL) electropherograms. Several typical wavelet transforms, including Haar, Daublets, Coiflets, and Symmlets, were evaluated. Four types of determining threshold methods, fixed form threshold, rigorous Stein's unbiased estimate of risk (rigorous SURE), heuristic SURE and minimax, combined with hard and soft thresholding methods were compared. The denoising study on synthetic signals showed that wave Symmlet 4 with a level decomposition of 5 and the thresholding method of heuristic SURE-hard provide the optimum denoising strategy. Using this strategy, the noise on CE-ECL electropherograms could be removed adequately. Compared with the Savitzky-Golay and Fourier transform denoising methods, DWT is an efficient method for noise removal with a better preservation of the shape of peaks.

Identification and molecular characterization of a peritrophin-like protein from fleshy prawn (Fenneropenaeus chinensis)

Peritrophin, one of the components of the peritrophic matrix, was first isolated from the intestine of insects. It is thought to protect insects from invasion of microorganisms and to stimulate digestion of food. Peritrophin-like proteins have also been found in crustaceans, as a component of the egg layer. In this study, one fragment of the peritrophin-like gene was obtained from fleshy prawn (Chinese shrimp) (Fenneropenaeus chinensis) by panning the T7 phage display library constructed with the shrimp hemocyte cDNA. The total sequence of the peritrophin cDNA was cloned by modified SMART cDNA and LD-PCR methods. The full cDNA is 1048 bp and the deduced protein is composed of 274 amino acids, including 21 amino acid signal peptide, and four peritrophin A domains and the latter three forming three chitin-binding domains. Similarity analysis results showed that the peritrophin-like protein from F chinensis has significant similarities with peritrophin-like and cortical rod proteins from other shrimp. It was inducing expression in hemocytes, heart, stomach, gut, and gills of the infected shrimp, and constitutive expression in the ovaries. No expression signal was detected in the hepatopancreas of either infected or noninfected shrimp. The recombinant peritrophin-like protein has the activity of binding Gram-negative bacteria and strong binding activity to chitin. Therefore, the bacteria and chitin binding activities of the peritrophin-like protein suggest that it may plays a role in immune defense and other physiological resposes. (c) 2005 Elsevier Ltd. All rights reserved.

Diagnostique visuel des carences nutritionnelles du cotonnier.

2013

Utilisation du sisvar dans l'analyse de données expérimentales.

2013

Metabolic Engineering, metabolite profiling and machine learning to investigate the phloem-mobile signal in systemic acquired resistance in tobacco

Draper, J., Darby, R.M., Beckmann, M., Maddison, A.L., Mondhe, M., Sheldrick, C., Taylor, J., Goodacre, R., and Kell, D.B. (2002) Metabolic Engineering, metabolite profiling and machine learning to investigate the phloem-mobile signal in systemic acquired resistance in tobacco. First International Congress on Plant Metabolomics, Wageningen, The Netherlands

Albucasis, Traitier de Cyrurgie: Edition de la traduction en ancien fran?ais de la Chirurgie d'Abu'l Qasim Halaf Ibn ?Abbas al-Zahrawi du manuscrit BNF, fran?ais 1318.

Trotter, David, Albucasis, Traitier de Cyrurgie: Edition de la traduction en ancien fran?ais de la Chirurgie d'Abu'l Qasim Halaf Ibn ?Abbas al-Zahrawi du manuscrit BNF, fran?ais 1318 (Niemeyer, 2005)

Les manuscrits latins de la Chirurgia d'Albucasis et la lexicographie du latin m?di?val

Trotter, David, 'Les manuscrits latins de la Chirurgia d'Albucasis et la lexicographie du latin m?di?val', Archivum Latinitatis Medii Aevi (Bulletin Du Cange) (2001) 59(1) pp.181-202 RAE2008

Obraz stosunków językowych polsko-niemieckich w historii języka polskiego. Księga sądu wójtowskiego m. Opola z lat 1698-1721 jako językowy wyraz kontaktów międzyetnicznych

Wydział Filologii Polskiej i Klasycznej: Instytut Filologii Polskiej

Synteza i struktura nowych aminowych analogów ansamycynowego antybiotyku rifampicyny

Wydział Chemii: Zakład Biochemii

L'Ane promeneur, ou Critès promené par son ane : Chef-d'oeuvre pour servir d'Apologie au Goût, aux Moeurs, à l'Esprit, et aux Découvertes du siècle

Première edition revue, corrigée, et précédée d'une Préface à la Mosaïque, dans le plus nouveau goût.