Search results for "HeLa"
showing 10 items of 738 documents
Kif3a interacts with Dynactin subunit p150 Glued to organize centriole subdistal appendages.
2013
Formation of cilia, microtubule-based structures that function in propulsion and sensation, requires Kif3a, a subunit of Kinesin II essential for intraflagellar transport (IFT). We have found that, Kif3a is also required to organize centrioles. In the absence of Kif3a, the subdistal appendages of centrioles are disorganized and lack p150(Glued) and Ninein. Consequently, microtubule anchoring, centriole cohesion and basal foot formation are abrogated by loss of Kif3a. Kif3a localizes to the mother centriole and interacts with the Dynactin subunit p150(Glued) . Depletion of p150(Glued) phenocopies the effects of loss of Kif3a, indicating that Kif3a recruitment of p150(Glued) is critical for s…
Photochemical ligand rearrangement in dirhodium(II) compounds. Structure of Rh2(O2CCH3)2(η2-O2CCH3)[(C6H4)PPh2] (η2-PCCl)(PCClP-ClC6H4)Ph2
1995
Abstract The photochemical reaction of the adducts Rh2(O2CCH3)3[(C6H4)P(o-ClC6H4)Ph]· (P(p-XC6H4)3) (X=H, Me, Cl), yield the compounds Rh2(O2CCH3)2(η2-O2CCH3)[(p-XC6H3)P (p-XC6H4)2](η2-PCCl), (PCCl=P(o-ClC6H4)Ph2) in a ligand rearrangement reaction that involves activation of CH and RhC bonds. The factors that favour this process are studied by carrying out photochemical reactions with different phosphines. The structures of Rh2(O2CCH3)2(η2-O2CCH3) [(C6H4)PPh2](η2-PCCl) has been determined by X-ray diffraction. Mr=1321.1, orthorhombic, space group Pbcn, a=20.339(8), b=20.07(6), c=23.07(3) A , V=9413(3) A 3 , Z=8, D x =1.86 g cm −3 . Mo Kα radiation (graphite crystal monochromator, λ=0.071…
Malonato complexes of oxidovanadium(IV): Synthesis, structural characterization and exploration of their insulin mimetic properties
2011
Abstract Several bis-malonatooxidovanadium(IV) complexes of the general type [M2(H2O)n][VO(mal)2(H2O)] (where M = Li(1), Na(2), K(3), Cs(4) and NH4(5); n = 3.5, 1, 3, 1 and 1, respectively) were isolated in good yield and high purity. These complexes were fully characterized by various physicochemical techniques (elemental analysis, UV–Vis, IR, EPR, CV, etc.) complexes 1, 2 and 3 were structurally characterized by single crystal X-ray diffraction technique. In vivo antidiabetic properties of bis-malonato complexes 1, 2, 3 and 5 have been studied using Streptozotocin induced diabetic rats. Significant lowering of blood sugar level has been noticed. At the same time these complexes were found…
Dinuclear Palladium(II) and -(III) Compounds with O,O-Chelating Ligands. Room-Temperature Direct 2-Phenylation of 1-Methylindole
2012
New dinuclear palladium(III) compounds of general formula Pd2[(C6H4)PPh2]2[O–O]2Cl2, O–O being chelating phenolates C6H4OC(O)R (R = CH3, 3a; R = C2H5, 3b; R = OPh, 3c) or acetylacetonates RC(O)CHC(O)R (R = CH3, 4a; R = CF3, 4b; R = C(CH3)3, 4c), have been obtained by oxidation with PhICl2 of the corresponding palladium(II) compounds. The stability of the new compounds has been studied by 31P NMR spectroscopy from 200 to 298 K. DFT calculations of the stability of the complexes have also been performed. In agreement with these calculations, only compound Pd2[(C6H4)PPh2]2[(CF3C(O)CHC(O)CF3]2Cl2, 6b, showed the highest thermal stability. 6b was characterized by X-ray diffraction methods, prese…
Synthesis and X-ray crystal structure of manganese(II) pyridine-2-thiolate
1997
2:1 complexes of pyridine-2(1H)-thione (LH) with manganese(II) were prepared: (LH)2MnCl2, (LH)2MnBr2 and [L2Mn]n. The polymeric chain structure of [L2Mn]n contains a distorted octahedrally coordinated manganese (MnN2S4) with chelating ligands, the N-atoms are in cis positions and the S-atoms of the pyridine-2-thiolates bridging; crystallographic data for [C10H8MnN2S2]n: space group C2/c (monoclinic), and R1 = 0.0571 for 1326 reflexes with Fo4σ(Fo).
Extraction of uranyl ions from aqueous solutions using silica-gel-bound macrocycles for alpha contaminated waste water treatment
2004
Abstract The efficiency for the extraction of U(VI) of new modified silica gels, namely N-tripropionate (or N-triacetate)-substituted tetraazamacrocycles-bound silica gels, has been studied. The effect of the nature of the ligand, the pH and the temperature was studied both in batch experiments as well as in continuous extraction. These silica gels are good candidates for the extraction of U(VI) when compared to a commercially available acid-type chelating resin. The breakthrough and regeneration tests showed that the total removal of U(VI) from a contaminated solution can be achieved by using a column packed with such tetraazamacrocycles-bound silica gels. Finally, the use of a modified si…
Effect of EDTA and citrate on the functional activity of the first component of complement, C1, and the C1q subcomponent.
1985
The first component of complement, C1, is a calcium-dependent complex of the three distinct subcomponents, C1q, C1r, and C1s. Earlier observations revealed that treatment of C1 with EDTA led to a loss of hemolytic C1 activity even after recalcification. Therefore, it was of interest to study whether EDTA has an additional effect on C1 and its subcomponents, beside its chelating capacity. The chelating effect of EDTA was compared to that of citrate. It was found that treatment of C1 or C1 with EDTA followed by addition of Ca++ led to a loss of hemolytic activity up to 90%, depending on EDTA concentration. Even pretreatment of EDTA with varying amounts of Ca++ did not prevent the inactivation…
cis-Aquabis[bis(diphenylphosphino)ethane-κ2 P,P′]chlororuthenium(II) hexafluorophosphate dichloromethane sesquisolvate hemihydrate
2006
In the title compound, [RuCl(C26H24P)2(H2O)]PF6·1.5CH2Cl2·0.5H2O, the complex RuII cation is in a slightly distorted octahedral environment, chelated by two bis(diphenylphosphino)ethane ligands, with a water molecule and a chloride anion in a mutually cis geometry completing the coordination.
Separation of chelating agents as copper complexes by capillary zone electrophoresis using quaternary ammonium bromides as additives in N-methylforma…
2006
This study presents the use of quaternary ammonium bromides as additives in N-methylformamide (NMF) for the separation and quantification of chelating agents as copper complexes by capillary zone electrophoresis (CZE). The new quaternary ammonium bromides were synthesized in our laboratory and used for the first time for CZE applications performed in NMF media. The methods were developed and optimized for determination of six chelating agents (trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), nitrilotriacetic acid (NTA) and trieth…
A 4-tert-butylcalix[4]arene tetrahydroxamate podand based on the 1-oxypiperidine-2-one (1,2-PIPO−) chelate. Self-assembly into a supramolecular ionop…
2014
An octadentate tetrahydroxamic calix[4]arene podand incorporating 1-hydroxypiperidine-2-one (1,2-PIPOH) binding units has been designed as a specific chelator for tetravalent metal cations like Zr4+ or Hf4+. This receptor, which can be considered as the first ever abiotic ligand possessing only cyclic six-membered hydroxamate groups, has been synthesized and characterized in its tetraprotonated form (1H4). Contrary to expectation, however, this new chelator did not form a 1 : 1 complex upon reaction with M(acac)4 (M = Zr and Hf; acac = acetylacetonate), but rather self-assembled into a dimeric species of 2 : 2 stoichiometry. The latter could be characterized in solution by mass spectrometry…