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B Complex (b + complex)
Selected AbstractsNF,B Activation in Mouse Pituitary: Comparison of Response to Interleukin-1, and LipopolysaccharideJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2003P. Parnet Abstract The mouse anterior pituitary contains both types of interleukin (IL)-1 receptors, IL-1 receptor type I (IL-1RI) and IL-1 receptor type II (IL-1RII). These receptors are expressed mainly on somatotroph cells. In the present study, the ability of the mouse pituitary to respond in vivo to IL-1 or to lipopolysaccharide (LPS) was demonstrated by measuring, with an electrophoretic mobility shift assay, the presence of an active NF,B complex in cell nuclei from pituitaries of mice injected intraperitoneally with recombinant rat-IL-1, or LPS. Using immunohistochemistry with an antibody directed against the p65 NF,B subunit, a rapid and transient NF,B response to LPS was observed. This response was present predominantly in the nuclei of glial fibrillary acidic protein (GFAP)-positive cells and F4/80-labelled cells of the posterior and the anterior pituitary 15 min after stimulation and became faint after 2 h. In comparison, the early and strong NF,B response to IL-1, treatment was localized into somatotroph cells, GFAP positive cells and F4/80-labelled cells of the posterior and anterior pituitary. Activation of NF,B in response to IL-1, was no longer apparent in IL-1RI knockout mice, confirming that this receptor is essential for the transduction of IL-1 signal in the pituitary, but remained after LPS treatment. In addition, we investigated the effect of IL-1 on target genes by measuring the mRNA and proteins synthesis of growth hormone (GH), IL-6 and IL-1ra in the pituitary and the plasma. IL-1, was shown to induce a rapid and strong synthesis of IL-6 and IL-1ra in the pituitary but failed to regulate GH contents or release. These data suggest that the pituitary is able to respond to a systemic infection via cytokine-mediated responses transduced by IL-1. [source] Micronutrients and Adverse Pregnancy Outcomes in the Context of HIV InfectionNUTRITION REVIEWS, Issue 7 2004Dr.P.H., Wafaie Fawzi M.B. HIV infection is a global public health problem, particularly in Africa. Concurrently, micronutrient deficiencies and adverse pregnancy outcomes are prevalent in the same settings. Supplements containing B complex and vitamins C and E were efficacious in reducing adverse pregnancy outcomes, including fetal loss, low birth weight, and prematurity among HIV-infected women; the generalizability of this finding to uninfected women is being examined. There is little encouragement from published studies to provide prenatal vitamin A supplements in HIV infection, particularly in light of significantly higher risk of mother-to-child transmission observed in one trial. The efficacy and safety of prenatal zinc and selenium supplements on these outcomes need to be examined in randomized trials. [source] Both Fc,RIV and Fc,RIII are essential receptors mediating type II and type III autoimmune responses via FcR,-LAT-dependent generation of C5aEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 12 2009Shahzad N. Syed Abstract Fc,RIV is a relatively new IgG Fc receptor (Fc,R) that is reported to contribute to the pathogenesis of autoimmune diseases, although its specific role in relation to Fc,RIII, complement and IgG2 subclasses remains uncertain. Here we define Fc,RIV on macrophages as a receptor for soluble IgG2a/b complexes but not for cellular bound IgG2a and show that simultaneous activation of Fc,RIV and Fc,RIII is critical to mediate certain type II/III autoimmune responses. Fc,RIII-deficient mice display compensatory enhanced Fc,RIV expression, are protected from lung inflammation after deposition of IgG complexes, and show reduced sensitivity to IgG2a/b-mediated hemolytic anemia, indicating that increased Fc,RIV alone is not sufficient to trigger these diseases in the absence of Fc,RIII. Importantly, however, blockade of Fc,RIV is also effective in inhibiting phagocytosis and cytokine production in IgG2b-induced anemia and acute lung injury, processes that display a further dependence on C5a anaphylatoxin receptor. Using gene deletion and functional inhibition studies, we found that Fc,RIII and Fc,RIV are each essential to trigger an FcR,-linker for activation of T-cell-dependent signal that drives C5a production in the Arthus reaction. Together, the results demonstrate a combined requirement for Fc,RIII and Fc,RIV in autoimmune injury, and identify the linker for activation of T cells adaptor as an integral component of linked Fc,R and C5a anaphylatoxin receptor activation to generate inflammation. [source] A Theoretical Investigation of Substituent Effects on the Absorption and Emission Properties of a Series of Terpyridylplatinum(II) Acetylide ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2005Xiao-Juan Liu Abstract A comprehensive calculational investigation has been carried out on a series of complexes of the type [(terpyridyl-R1)Pt(C,C-R2)], where terpyridyl-R1 is a series of substituted 2,2':6',2"-terpyridyl ligands and C,C-R2 is a series of substituted acetylide ligands. In one series of complexes (I), the energy of the electronic excited state is varied by changing the substituents on the terpyridyl ligand (R1). In a second series of complexes (II), this electronic structure variation is obtained by changing the para substituents (R2) of the acetylide ligand. The effect of varying the substituents on the lowest-energy excited states of the complexes has been assessed by calculating their electronic structures and excitation energies. We anticipated that introduction of electron-withdrawing substituents on the terpyridyl ligand will benefit the LLCT (or MLCT) and prohibit the nonradiative pathways via d-d transitions in these complexes; introduction of electron-donating substituents on the acetylide ligand can also prohibit the nonradiative pathways by increasing the energy gaps between the HOMO,LUMO and d-d transitions. The results also reveal that the lowest-energy excitations of all complexes of series I and IIa,b complexes are dominated by a ,(C,C),,,,*(terp) (LLCT) transition mixed with some energetically d,(Pt),,,terpyridyl (MLCT) transition. However, for the complexes IIc,IId, in which phenyl rings are introduced on the acetylide ligand, the lowest-lying absorptions of IIc and IId are predominately LLCT in character, with less MLCT mixture, due to a lower contribution of the Pt(d) orbital to the HOMO, while for IIe, with a stronger donor on the acetylide, the lowest-lying absorption is completely LLCT in character. The absorption and emission calculations using the TDDFT method are based on the optimized geometries obtained at the B3LYP/LanL2DZ and CIS/LanL2DZ levels, respectively. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Rational Design of Chelating Phosphine Functionalized Os(II) Emitters and Fabrication of Orange Polymer Light-Emitting Diodes Using Solution Process,ADVANCED FUNCTIONAL MATERIALS, Issue 2 2008M. Cheng Abstract A new series of charge neutral Os(II) pyridyl azolate complexes with either bis(diphenylphosphino)methane (dppm) or cis -1,2-bis(diphenylphosphino)ethene (dppee) chelates were synthesized, and their structural, electrochemical, photophysical properties and thermodynamic relationship were established. For the dppm derivatives 3a and 4a, the pyridyl azolate chromophores adopt an eclipse orientation with both azolate segments aligned trans to each other, and with the pyridyl groups resided the sites that are opposite to the phosphorus atoms. In sharp contrast, the reactions with dppee ligand gave rise to the formation of two structural isomers for all three kind of azole chromophores, with both azolate or neutral heterocycles (i.e., pyridyl or isoquinolinyl fragments) located at the mutual trans -disposition around the Os metal (denoted as series of a and b complexes). These chelating phosphines Os(II) complexes show remarkably high thermal stability, among which and several exhibit nearly unitary phosphorescence yield in deaerated solution at RT. A polymer light-emitting device (PLED) prepared using 0.4 mol % of 5a as dopant in a blend of poly(vinylcarbazole) (PVK) and 30 wt % of 2- tert -butylphenyl-5-biphenyl-1,3,4-oxadiazole (PBD) exhibits yellow emission with brightness of 7208 cd m,2, an external quantum efficiency of 10.4 % and luminous efficiency of 36.1 cd A,1 at current density of 20 mA cm,2. Upon changing to 1.6 mol % of 6a, the result showed even better brightness of 9212 cd m,2, external quantum efficiency of 12.5 % and luminous efficiency of 46.1 cd A,1 at 20 mA cm,2, while the max. external quantum efficiency of both devices reaches as high as 11.7 % and 13.3 %, respectively. The high PL quantum efficiency, non-ionic nature, and short radiative lifetime are believed to be the determining factors for this unprecedented achievement. 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