Recent advances in the MS analysis of glycoproteins: Capillary and microfluidic workflows

Recent developments in bioanalytical instrumentation, MS detection, and computational data analysis approaches have provided researchers with capabilities for interrogating the complex cellular glycoproteome, to help gain a better insight into the cellular and physiological processes that are associated with a disease and to facilitate the efforts centered on identifying disease-specific biomarkers. This review describes the progress achieved in the characterization of protein glycosylation by using advanced capillary and microfluidic MS technologies. The major steps involved in large-scale glycoproteomic analysis approaches are discussed, with special emphasis given to workflows that have evolved around complex MS detection functions. In addition, quantitative analysis strategies are assessed, and the bioinformatics aspects of glycoproteomic data processing are summarized. The developments in commercial and custom fabricated microfluidic front-end platforms to ESI- and MALDI-MS instrumentation, for addressing major challenges in carbohydrate analysis such as sensitivity, throughput, and ability to perform structural characterization, are further evaluated and illustrated with relevant examples.     

Artemisinin evaluation in Romanian Artemisia annua wild plants using a new HPLC/MS method

Artemisinin, a sesquiterpene lactone from Artemisia annua L., has received considerable attention in the last few decades as a potent antimalarial drug. Artemisinin has rather low toxicity; it is effective against drug-resistant Plasmodium species and against cerebral malaria. This study reports the development of a rapid and sensitive assay for the quantification of artemisinin in A. annua by reversed phase HPLC/MS. In the selected optimal experimental conditions, artemisinin exhibited a well-defined chromatographic peak with a retention time of 2 ± 0.2 min. The chromatographic signal shows a linear dependence with artemisinin concentration, enabling the use of this signal for artemisinin quantification according to the following regression equation: y = 2665.40x - 14697.61. The correlation coefficient (R(2)) was 0.9989. For every concentration within the range of the standard curve (0.1-2 μg mL(-1)), accuracy was between 95 and 104%. Artemisinin content in Romanian A. annua wild plants varies between 0.17 and 0.21% (dry weight basis).     

Vector Potential Theory on Nonsmooth Domains in R3 and Applications to Electromagnetic Scattering

We study boundary value problems for the time-harmonic form of the Maxwell equations, as well as for other related systems of equations, on arbitrary Lipschitz domains in the three-dimensional Euclidean space. The main goal is to develop the corresponding theory for L^p-integrable bounday data for optimal values of p’s. We also discuss a number of relevant applications in electromagnetic scattering.     

Sharp Hodge decompositions in two and three dimensional Lipschitz domainsDécompositions de Hodge optimales pour les domaines lipschitziens en dimensions deux et trois

We identify the optimal range of coefficients s, p for which differential forms with coefficients in the Sobolev space $\text{L}{}^{\mathrm{p}}{}_{\mathrm{s}}\text{(Ω)}$ admit natural Hodge decompositions in arbitrary two and three dimensional Lipschitz domains $\text{Ω}$. To cite this article: D. Mitrea, M. Mitrea, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 109–112     

Contributions to the analytical chemistry of osmium and ruthenium-IX: the dimercapto derivatives of asymmetric triazine as colour reagents for osmium

The parameters of the reaction of osmium with 3,5-dimercapto-6-(ethylcarboxy)-1,2,4-triazine have been studied and the optimum conditions for the spectrophotometric determination of osmium over the range 0.5-18.0 ppm determined. The coloured product contains the components in the ratio 1:2 metal:ligand.     

Evaluation by chemical parameters of the pollution state of the agricultural-industrial settlement of the Fucino Plain

In the present work are reported the results of a monitoring on a vast scale, carried out through evaluation of opportune chemical parameters, of the pollution state of the agricultural-industrial settlement of the Fucino Plain. The parameters took into consideration have been the presence of wide consumption pesticides and of ionic species as Cl-, NO2-, NO3-, NH4+, the quantification of the dissolved oxygen, of the temperature, of the conductivity, of pH and eH. Collected data are used for chemometric elaboration. The water systems examined, by means of drawing campaigns carried out at regular intervals in winter, spring, summer, and autumnal seasons, are represented by superficial waters constituting a network of irrigation canals fed by stratum and meteoric waters. In this work are reported the results relative to the drawing campaigns.     

Boundary value problems for the Laplacian in convex and semiconvex domains

We study the fully inhomogeneous Dirichlet problem for the Laplacian in bounded convex domains in Rn, when the size/smoothness of both the data and the solution are measured on scales of Besov and Triebel-Lizorkin spaces. As a preamble, we deal with the Dirichlet and Regularity problems for harmonic functions in convex domains, with optimal nontangential maximal function estimates. As a corollary, sharp estimates for the Green potential are obtained in a variety of contexts, including local Hardy spaces. A substantial part of this analysis applies to bounded semiconvex domains (i.e., Lipschitz domains satisfying a uniform exterior ball condition).     

A new class of generalized close-to-starlike functions defined by the Srivastava-Attiya operator

In this paper, we consider a new class CS*s,b of generalized close-to-starlike functions, which is defined by means of the Srivastava-Attiya operator Js,b involving the Hurwitz-Lerch Zeta function Φ(z, s, a). Basic results such as inclusion relations, coefficient inequalities and other interesting properties of this class are investigated. Relevant connections of some of the results presented here with those that were obtained in earlier investigations are pointed out briefly.