Search results for "complex"
showing 10 items of 5889 documents
Comparison of different phosphorus-containing ligands complexing 68Ga for PET-imaging of bone metabolism
2010
Abstract 99mTc-phosphonate structures are well established tracers for bone tumour imaging. Our objective was to investigate different 68Ga-labelled phosphonate ligands concerning labelling kinetics, binding to hydroxyapatite and bone imaging using μ-PET. Seven macrocyclic phosphorus-containing ligands and EDTMP were labelled in nanomolar scale with n.c.a. 68Ga in Na-HEPES buffer at pH∼4. Except for DOTP, all ligands were labelled with >92% yield. Binding of the 68Ga-ligand complexes on hydroxyapatite was analysed to evaluate the effect of the number of the phosphorus acid groups on adsorption parameters. Adsorption of 68Ga-EDTMP and 68Ga-DOTP was >83%. For the 68Ga-NOTA-phosphonates …
Soil Carbon, Nitrogen and Phosphorus Dynamics as Affected by Solarization Alone or Combined with Organic Amendment
2006
Soil solarization, alone or combined with organic amendment, is an increasingly attractive approach for managing soil-borne plant pathogens in agricultural soils. Even though it consists in a relatively mild heating treatment, the increased soil temperature may strongly affect soil microbial processes and nutrients dynamics. This study aimed to investigate the impact of solarization, either with or without addition of farmyard manure, in soil dynamics of various C, N and P pools. Changes in total C, N and P contents and in some functionally-related labile pools (soil microbial biomass C and N, K2SO4-extractable C and N, basal respiration, KCl-exchangeable ammonium and nitrate, and water-sol…
Iron(II) complexes of naphthalenes. X-ray structure of [cyclopentadienyl-iron(II)-η6-octamethylnaphthalene]PF6
1992
Abstract Complex ions [cyclopentadienyl-Fe(methylnaphthalene)]+ with 4 to 8 methyl substituents have been prepared from [CpFe(o-dichlorobenzene)]+ by a photochemical ligand exchange. Complexation shifts have been determined for 1H and 13C resonances of the η6-bonded naphthalenes. The X-ray structure of [CpFe(octamethylnaphthalene)]PF6 0.5 acetone has been determined. Crystals are monoclinic, the space group C2/c with unit-cell dimensions a = 10.689(4), b = 22.391(5), c = 20.550(4)A, β = 93.41(2)°, Z = 8. The structure determination established a distorted molecular geometry of the octamethylnaphthalene that is different from the free arene and its Cr(CO)3 complex.
Mono(cyclopentadienyl)titanium complexes containing a sulfide-bridged bis(phenolato) ligand. Molecular structure of Ti{2,2′-S(OC6H2-4-Me-6-tBu)2}(η5-…
2001
A series of titanium complexes containing a sulfur-bridged chelating bis(phenolato) ligand, Ti{2,2′-S(OC 6 H 2 -4-Me-6- t Bu) 2 }(η 5 -C 5 R 5 )Cl (R=H, Me; R 5 =1,3-(SiMe 3 ) 2 H 3 ), were prepared by the reaction of the dilithium derivative Li 2 [2,2′-S(OC 6 H 2 -4-Me-6- t Bu) 2 ] with Ti(η 5 -C 5 R 5 )Cl 3 . Alkylation of the chloro complexes gave complexes of the type Ti{2,2′-S(OC 6 H 2 -4-Me-6- t Bu) 2 }(η 5 -C 5 R 5 )R′ (R′=Me, CH 2 Ph). The crystal structure of the chloro complex Ti{2,2′-S(OC 6 H 2 -4-Me-6- t Bu) 2 }(η 5 -C 5 H 5 )Cl has been determined by X-ray diffraction and shows a monomeric four-legged piano-stool structure with the sulfur and chlorine atoms in trans positions. …
Hf27Si6P10, a novel metal-rich compound with P2 groups
2000
The new ternary metal rich compound Hf27Si6P10 has been synthesized by reduction of HfP with Hf and Si; Hf27Si6P10 crystallizes in a new structure type, a characteristic and unexpected feature of which is the presence of P2 groups; the structural results are interpreted with the aid of high-level band structure calculations.
An exon junction complex‐independent function of Barentsz in neuromuscular synapse growth
2021
The exon junction complex controls the translation, degradation, and localization of spliced mRNAs, and three of its core subunits also play a role in splicing. Here, we show that a fourth subunit, Barentsz, has distinct functions within and separate from the exon junction complex in Drosophila neuromuscular development. The distribution of mitochondria in larval muscles requires Barentsz as well as other exon junction complex subunits and is not rescued by a Barentsz transgene in which residues required for binding to the core subunit eIF4AIII are mutated. In contrast, interactions with the exon junction complex are not required for Barentsz to promote the growth of neuromuscular synapses.…
Determination of metal inventory and current efficiency in commercial aluminum reduction cells
1971
A method for the determination of the metal inventory in commercial aluminum reduction cells, based on radioisotope dilution, has been developed, employing a198Au tracer. By taking a large number of samples from the cells, the current efficiency is evaluated from the slope of the cumulative metal inventory vs time data. The method allows a determination of the current efficiency over a period of 2 to 3 days with a relative precision of approximately 1 pct. The paper gives a thorough discussion of the sources of error inherent in the procedure suggested.
Dihydrogen complexes of metalloporphyrins: characterization and catalytic hydrogen oxidation activity
1992
A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H{sub 2}) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by {sup 1}H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T{sub 1}) range from 0.92 to 1.18 {angstrom}. The first example of a bimetallic bridging dihydrogen complex, Ru{sub 2}(DPB)(*IM){sub 2}(H{sub 2}), was also prepared. The H{sub 2} ligand is simultaneously bound to both Ru-metal centers. High-field {sup 1}H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H{sub 2} ligand for this complex. Analysis of this splitting suggests that th…
C1q secreted in the tumour microenvironment promotes tumour growth in the absence of complement activation
2012
We have recently shown that locally secreted C1q is involved in trophoblast invasion of decidua during pregnancy (Agostinis et al., J. Immunol. 2010;185;4420–4429). Since this physiologic process resembles to some extent tumor progression, we sought to investigate if C1q plays a similar role in tumor development and progression. Immunohistochemical analysis of several solid tumours including colon, prostate, lung and breast cancer and melanoma revealed the presence of C1q that was localized on the vascular endothelium and also distributed in the stroma in the absence of C4. To investigate the in vivo role of C1q in tumour development, 6/8 week old female WT and C1q−/− C57BL/6 mice received …
Inorganic Nanoparticle as a Carrier for Hepatitis B Viral Capsids
2011
Virus like particles (VLP) are used to transport immune response-modulating agents to target cells to treat them. In order to deliver a high concentration of VLP to the cell, a number of VLP can be attached to a nanoparticle to be used as a nanolorry. In this study, SiO2 nanoparticles were attached to Hepatitis B VLP. Spectrophotometry measurements, electron, and fluorescent microscopy evidence showed that the SiO2 – Hepatitis B VLP complexes were formed.