Search results for "Phosphor"
showing 10 items of 1952 documents
Capillary electrophoresis–inductively coupled plasma-mass spectrometry hyphenation for the determination at the nanogram scale of metal affinities an…
2012
Abstract A screening strategy based on hyphenated capillary electrophoresis and inductively coupled plasma mass spectrometry (CE–ICP-MS) was developed to classify phosphorylated ligands according to their europium(III) binding affinity in a hydro-organic medium (sodium formate, pH 3.7, H2O/MeOH 90:10, v/v). Taking advantage of the high sensibility of ICP-MS for detecting phosphorus, this method enabled to assess the affinity of a variety of phosphorylated compounds, including phosphine oxides, thiophosphines, phosphonates, and phosphinates, in less than 1 h and using less than 5 ng of substance. By varying the total europium concentration, complexation constants could be determined accordin…
Synthèse et caractérisation de phosphine, borane, amine sur plateforme ferrocène polyfonctionnelle
2016
Ferrocene platforms are useful in coordination chemistry and catalysis thanks to their robustness and versatile functionalization. Ferrocene backbone allows the implantation of several key functional groups in a restricted space, inducing close proximity and potential polyfunctional cooperation (see for instance ferrocenyl polyphosphine chemistry). Ansa ferrocene and ferrocene bearing conformational control inducing groups maximizing the proximity of key groups have been widely reported.The first part of this thesis focuses on the synthesis of new borylated cyclopentadienyl, and their use in formation of borylated metallocenes bearing conformational constraints. NMR analysis and DFT calcula…
The use of glyphosate as the sole source of phosphorus or carbon for the selection of soil-borne fungal strains capable to degrade this herbicide
1997
Abstract The herbicide glyphosate was used as a selection agent for isolation of fungal strains capable to degrade phosphorus-to-carbon bond from standard sandy-clay soil. The studies have shown that the herbicide used in Martin medium as a sole source of phosphorus br carbon caused the decrease of the fungal population and substantially changed strain composition, thus selecting those which are able to degrade glyphosate.
Adaptation of Fusarium oxysporum and Fusarium dimerum to the specific aquatic environment provided by the water systems of hospitals.
2015
SPE IPM MERS EA; International audience; Members of the Fusarium group were recently detected in water distribution systems of several hospitals in the world. An epidemiological investigation was conducted over 2 years in hospital buildings in Dijon and Nancy (France) and in non-hospital buildings in Dijon. The fungi were detected only within the water distribution systems of the hospital buildings and also, but at very low concentrations, in the urban water network of Nancy. All fungi were identified as Fusarium oxysporum species complex (FOSC) and Fusarium dimerum species complex (FDSC) by sequencing part of the translation elongation factor 1- alpha (TEF-1a) gene. Very low diversity was …
As2O3-induced oxidative stress and cycle progression in a human intestinal epithelial cell line (Caco-2)
2007
Foods and drinking water are the main routes for human exposure to inorganic arsenic, the intestinal epithelium being the first barrier against such exogenous toxicants. The present study evaluates the effect of As(III) (0.5-25 microM) upon Caco-2 cells as an intestinal epithelia model. Cell viability, intracellular formation of reactive oxygen species (ROS), mitochondrial membrane potential (Deltapsim) changes, and cell cycle distribution in exposed cultures were evaluated. The intracellular production of ROS was seen to increase in a non-dose dependent manner at all concentrations tested, with impairment of cell mitochondrial enzyme function secondary to a loss of Deltapsim. Concentration…
Escherichia coli cytolethal distending toxin blocks the HeLa cell cycle at the G2/M transition by preventing cdc2 protein kinase dephosphorylation an…
1997
Cytolethal distending toxins (CDT) constitute an emerging heterogeneous family of bacterial toxins whose common biological property is to inhibit the proliferation of cells in culture by blocking their cycle at G2/M phase. In this study, we investigated the molecular mechanisms underlying the block caused by CDT from Escherichia coli on synchronized HeLa cell cultures. To this end, we studied specifically the behavior of the two subunits of the complex that determines entry into mitosis, i.e., cyclin B1, the regulatory unit, and cdc2 protein kinase, the catalytic unit. We thus demonstrate that CDT causes cell accumulation in G2 and not in M, that it does not slow the progression of cells th…
Type III Secretion-Dependent Cell Cycle Block Caused in HeLa Cells by Enteropathogenic Escherichia coliO103
2001
ABSTRACT Rabbit enteropathogenic Escherichia coli (EPEC) O103 induces in HeLa cells an irreversible cytopathic effect characterized by the recruitment of focal adhesions, formation of stress fibers, and inhibition of cell proliferation. We have characterized the modalities of the proliferation arrest and investigated its underlying mechanisms. We found that HeLa cells that were exposed to the rabbit EPEC O103 strain E22 progressively accumulated at 4C DNA content and did not enter mitosis. A significant proportion of the cells were able to reinitiate DNA synthesis without division, leading to 8C DNA content. This cell cycle inhibition by E22 was abrogated in mutants lacking EspA, -B, and -D…
Regulated expression and phosphorylation of the 23-26-kDa ras protein in the sponge Geodia cydonium.
1990
We have cloned, sequenced and examined the sponge Geodia cydonium cDNA encoding a protein homologous to ras proteins. The sponge ras protein has a more conserved N-terminal region and a less conserved C-terminal region, especially in comparison to Dictyostelium discoideum; the similarity to human c-Ha-ras-1 and to Saccharomyces cerevisiae is less pronounced. The sponge ras cDNA comprises five TAG triplets; at the translational level these UAG termination codons are suppressed by a Gln-tRNA. The sponge ras protein was isolated and partially purified (23-26 kDa) and found to undergo phosphorylation at a threonine moiety, when dissociated cells were incubated in the presence of a homologous ag…
Up-conversion luminescence of GdVO4:Nd3+/Er3+ and GdVO4:Nd3+/Ho3+ phosphors under 808 nm excitation
2018
All authors acknowledge to the COST Action CM1403: The European upconversion network - from the design of photon-upconverting nanomaterials to biomedical applications (2014–2018). The authors from the University of Belgrade acknowledge the financial support of the Ministry of Education, Science and Technological Development of the Republic of Serbia (Project Nos. 45020 and 172056 ). K. S. acknowledges the Latvian National Research Program IMIS2 (Grant No. 302/2012 ). T. G. acknowledges the ERDF PostDoc project No. 1.1.1.2/VIAA/1/16/215 ( 1.1.1.2/16/I/001 ).
Serine in plants: biosynthesis, metabolism, and functions
2014
Serine (Ser) has a fundamental role in metabolism and signaling in living organisms. In plants, the existence of different pathways of Ser biosynthesis has complicated our understanding of this amino acid homeostasis. The photorespiratory glycolate pathway has been considered to be of major importance, whereas the nonphotorespiratory phosphorylated pathway has been relatively neglected. Recent advances indicate that the phosphorylated pathway has an important function in plant metabolism and development. Plants deficient in this pathway display developmental defects in embryos, male gametophytes, and roots. We propose that the phosphorylated pathway is more important than was initially thou…