Search results for "Dioxygen"
showing 10 items of 80 documents
Bioinspired manganese(II) complexes with a clickable ligand for immobilisation on a solid support.
2014
International audience; Clickable ligands like N,N′-bis((pyridin-2-yl)methyl)prop-2-yn-1-amine (L1) and N-((1-methyl-1H-imidazol-2-yl)methyl)-N-(pyridin-2-ylmethyl)prop-2-yn-1-amine (L2) have been used to synthesise a series of manganese(II) complexes for grafting onto appropriate solid supports. These ligands mimic the 2-His-1-carboxylate facial chelation present in the active site of the manganese-dependent dioxygenase (MndD), while the alkyne side function allows grafting of the ligand onto an azido-functionalised support using “click chemistry” methodologies. Such synthetic analogues of the MndD crystallise in the solid state as double halide or pseudohalide-bridged dinuclear manganese(…
Identification of a novel recurrent 1q42.2-1qter deletion in high risk MYCN single copy 11q deleted neuroblastomas
2012
Neuroblastoma is an aggressive embryonal tumor that accounts for similar to 15% of childhood cancer deaths. Hitherto, despite the availability of comprehensive genomic data on DNA copy number changes in neuroblastoma, relatively little is known about the genes driving neuroblastoma tumorigenesis. In this study, high resolution array comparative genome hybridization (CGH) was performed on 188 primary neuroblastoma tumors and 33 neuroblastoma cell lines to search for previously undetected recurrent DNA copy number gains and losses. A new recurrent distal chromosome 1q deletion (del(1)(q42.2qter)) was detected in seven cases. Further analysis of available array CGH datasets revealed 13 additio…
Differential Expression of the Demosponge (Suberites domuncula) Carotenoid Oxygenases in Response to Light: Protection Mechanism Against the Self-Pro…
2012
The demosponge Suberites domuncula has been described to contain high levels of a proteinaceous toxin, Suberitine, that displays haemolytic activityIn the present study this 7–8 kDa polypeptide has been isolated and was shown to exhibit also cytotoxic effects on cells of the same species. Addition of retinal, a recently identified metabolite of β-carotene that is abundantly present in S. domuncula was found to reduce both the haemolytic and the cell toxic activity of Suberitine at a molar ratio of 1:1. Spectroscopic analyses revealed that the interaction between β-carotene and Suberitine can be ascribed to a reversible energy transfer reaction. The enzyme that synthesises retinal in the spo…
Clarification of the oxidation state of cobalt corroles inheterogeneous and homogeneous catalytic reduction of dioxygen
2008
Co(III) corroles were investigated as efficient catalysts for the reduction of dioxygen in the presence of perchloric acid in both heterogeneous and homogeneous systems. The investigated compounds are (5,10,15-tris(pentafluorophenyl)corrole)cobalt (TPFCor)Co, (10-pentafluorophenyl-5,15-dimesitylcorrole)cobalt (F 5PhMes 2Cor)Co, and (5,10,15-trismesitylcorrole)cobalt (Mes 3Cor)Co, all of which contain bulky substituents at the three meso positions of the corrole macrocycle. Cyclic voltammetry and rotating ring-disk electrode voltammetry were used to examine the catalytic activity of the compounds when adsorbed on the surface of a graphite electrode in the presence of 1.0 M perchloric acid, a…
Inhibition of prolyl hydroxylation and procollagen processing in chick-embryo calvaria by a derivative of pyridine-2,4-dicarboxylate. Characterizatio…
1991
The biochemical and morphological consequences of procollagen prolyl 4-hydroxylase inhibition by pyridine-2,4-dicarboxylic acid (2,4-PDCA) and its diethyl ester (diethyl-2,4-PDC) were studied in chick-embryo calvaria, which predominantly synthesize type I collagen. Half-maximal inhibition of tissue hydroxyproline formation required 650 microM-2,4-PDCA, whereas the Ki with respect to chicken prolyl 4-hydroxylase in vitro was 2 microM. In contrast, half-maximal inhibition was caused by 10 microM-diethyl-2,4-PDC in the intact calvaria, although chicken prolyl 4-hydroxylase in vitro was not inhibited even at 1 mM. The collagenous material produced in the presence of diethyl-2,4-PDC showed an al…
A vertebrate globin expressed in the brain.
2000
Haemoglobins and myoglobins constitute related protein families that function in oxygen transport and storage in humans and other vertebrates. Here we report the identification of a third globin type in man and mouse. This protein is predominantly expressed in the brain, and therefore we have called it neuroglobin. Mouse neuroglobin is a monomer with a high oxygen affinity (half saturation pressure, P50 approximately 2 torr). Analogous to myoglobin, neuroglobin may increase the availability of oxygen to brain tissue. The human neuroglobin gene (NGB), located on chromosome 14q24, has a unique exon-intron structure. Neuroglobin represents a distinct protein family that diverged early in metaz…
Chronic lymphocytic leukemia nurse-like cells express hepatocyte growth factor receptor (c-MET) and indoleamine 2,3-dioxygenase and display features …
2014
Hepatocyte growth factor, produced by stromal and follicular dendritic cells, and present at high concentrations in the sera of patients with chronic lymphocytic leukemia, prolongs the survival of leukemic B cells by interacting with their receptor, c-MET. It is, however, unknown whether hepatocyte growth factor influences microenvironmental cells, such as nurse-like cells, which deliver survival signals to the leukemic clone. We evaluated the expression of c-MET on nurse-like cells and monocytes from patients with chronic lymphocytic leukemia and searched for phenotypic/functional features supposed to be influenced by the hepatocyte growth factor/c-MET interaction. c-MET is expressed at hi…
Induction of tolerogenic lung CD4+ T cells by local treatment with a pSTAT-3 and pSTAT-5 inhibitor ameliorated experimental allergic asthma.
2010
Signal transducer and activator of transcription (STAT)-3 inhibitors play an important role in regulating immune responses. Galiellalactone (GL) is a fungal secondary metabolite known to interfere with the binding of phosphorylated signal transducer and activator of transcription (pSTAT)-3 as well of pSTAT-6 dimers to their target DNA in vitro. Intra nasal delivery of 50 μg GL into the lung of naive Balb/c mice induced FoxP3 expression locally and IL-10 production and IL-12p40 in RNA expression in the airways in vivo. In a murine model of allergic asthma, GL significantly suppressed the cardinal features of asthma, such as airway hyperresponsiveness, eosinophilia and mucus production, after…
PHD3 regulates EGFR internalization and signalling in tumours
2014
Tumours exploit their hypoxic microenvironment to induce a more aggressive phenotype, while curtailing the growth-inhibitory effects of hypoxia through mechanisms that are poorly understood. The prolyl hydroxylase PHD3 is regulated by hypoxia and plays an important role in tumour progression. Here we identify PHD3 as a central regulator of epidermal growth factor receptor (EGFR) activity through the control of EGFR internalization to restrain tumour growth. PHD3 controls EGFR activity by acting as a scaffolding protein that associates with the endocytic adaptor Eps15 and promotes the internalization of EGFR. In consequence, loss of PHD3 in tumour cells suppresses EGFR internalization and hy…
CCDC 213845: Experimental Crystal Structure Determination
2004
Related Article: F.Carre, R.J.P.Corriu, E.Lancelle-Beltran, A.Mehdi, C.Reye, R.Guilard, J.Sykora, A.van der Lee|2003|Dalton Trans.||3211|doi:10.1039/b304032a