69 research outputs found
Recommended from our members
Group 13 Decamethylmetallocenium Cations
Salts containing the decamethylmetallocenium cations, [( C5Me5) M-2](+) ( or Cp*M-2(+)) of the group 13 "metals" B, Al and Ga have been prepared using a variety of synthetic routes. Precursor molecules of the type Cp*2MX ( X = Cl, Br, Me) exhibit structural features that vary significantly depending on the size and electronegativity of the central atom. While salt metathesis, halide abstraction and methanide abstraction methods represent viable routes for the preparation of salts of Cp*B-2(+) and Cp*Al-2(+), acidolysis of a Cp* group from Cp*Ga-3 is the most reliable method for the synthesis of the analogous gallium cation. Gallocenium cations are less stable than either of the lighter congeneric cations since they prove to be susceptible to decomposition reactions involving the "back-transfer" of ligands from the counter anion. Density functional theory (DFT) calculations revealed that, whereas Cp*Ga-2(+) is predicted to adopt a molecular structure more similar to that of Cp*B-2(+), the electronic structure of the gallium cation bears a greater resemblance to that of Cp*Al-2(+).Chemistr
Single nucleotide polymorphism upstream of interleukin 28B associated with phase 1 and phase 2 of early viral kinetics in patients infected with HCV genotype 1
We studied the relationship between IL28B gene-related SNP rs12979860 and early viral kinetics (day 0–28) during peginterferon and ribavirin treatment, in 173 African Americans (AA) and 188 Caucasian Americans (CA) with HCV genotype 1
A Phase II Trial of Sorafenib in Metastatic Melanoma with Tissue Correlates
Sorafenib monotherapy in patients with metastatic melanoma was explored in this multi-institutional phase II study. In correlative studies the impact of sorafenib on cyclin D1 and Ki67 was assessed. mutational status and clinical activity. No significant changes in expression of cyclin D1 or Ki67 with sorafenib treatment were demonstrable in the 15 patients with pre-and post-treatment tumor samples. mutational status of the tumor was not associated with clinical activity and no significant effect of sorafenib on cyclin D1 or Ki67 was seen, suggesting that sorafenib is not an effective BRAF inhibitor or that additional signaling pathways are equally important in the patients who benefit from sorafenib
Patient-reported outcome measures of the impact of cancer on patient’s everyday lives: a systematic review
Purpose: Patients with advanced disease are living longer and commonly used patient-reported outcome measures (PROMs) may miss relevant elements of the quality of extended survival. This systematic review examines the measures used to capture aspects of the quality of survival including impact on patients’ everyday lives such as finances, work and family roles.
Methods: Searches were conducted in MEDLINE, EMBASE,
CINAHL and PsycINFO restricted to English language articles. Information on study characteristics, instruments and outcomes was systematically extracted and synthesised. A predefined set of criteria was used to rate the quality of studies.
Results: From 2761 potentially relevant articles, 22 met all inclusion criteria, including 10 concerning financial distress, 3 on roles and responsibilities and 9 on multiple aspects of social well-being. Generally, studies were not of high quality; many lacked bias free participant selection, had confounding factors and had not accounted for all participants. High levels of financial distress were reported and were associated with multiple demographic factors such as age and income. There were few reports concerned with impacts on patients’ roles/responsibilities in everyday life although practical and emotional struggles with parenting were identified. Social difficulties were common and associated with multiple factors including being a caregiver. Many studies were single time-point surveys and used non-validated measures. Exceptions were employment of the COST and Social Difficulties Inventory (SDI), validated measures of financial and social distress respectively.
Conclusions: Impact on some important parts of patients’ everyday lives is insufficiently and inconsistently captured. Further PROM development focussing on roles and responsibilities, including work and caring for dependents, is warranted.
Implications for Cancer Survivors: Factors such as finances, employment and responsibility for caring for dependents (e.g. children and elderly relatives) can affect the well-being of cancer survivors. There is a need to ensure that any instruments used to assess patients’ social well-being are broad enough to include these areas so that any difficulties arising can be better understood and appropriately supported
Structural Characterization and Redox Activity of a Uranyl Dimer and Transition-Metal Complexes of a Tetradentate BIAN Ligand
The synthesis and characterization
of a new ligand system combining the redox-active backbone of Ar-BIANs
(<i>N</i>,<i>N</i>′-bisÂ[(aryl)Âimino]Âacenaphthenes)
and a mixed-donor O–N–N–O salen-type binding
pocket is reported. Complexes of Co<sup>2+</sup>, Ni<sup>2+</sup>,
and UO<sub>2</sub><sup>2+</sup> were prepared and characterized through
single-crystal X-ray diffraction and electrochemical studies. The
Ni<sup>2+</sup> and Co<sup>2+</sup> complexes have been used as references
against which to compare the unique behaviors exhibited by the uranyl
(UO<sub>2</sub><sup>2+</sup>) complex, as the latter forms two distinct
solid-state structures with unusual oxo contacts to CH<sub>2</sub>Cl<sub>2</sub> and CHCl<sub>3</sub> and displays a rich electrochemical
profile that indicates a wide range of accessible metal oxidation
states through the formation of mixed-valent UÂ(VI)/UÂ(V) and UÂ(V)/UÂ(IV)
species in solution
Structural Characterization and Redox Activity of a Uranyl Dimer and Transition-Metal Complexes of a Tetradentate BIAN Ligand
The synthesis and characterization
of a new ligand system combining the redox-active backbone of Ar-BIANs
(<i>N</i>,<i>N</i>′-bisÂ[(aryl)Âimino]Âacenaphthenes)
and a mixed-donor O–N–N–O salen-type binding
pocket is reported. Complexes of Co<sup>2+</sup>, Ni<sup>2+</sup>,
and UO<sub>2</sub><sup>2+</sup> were prepared and characterized through
single-crystal X-ray diffraction and electrochemical studies. The
Ni<sup>2+</sup> and Co<sup>2+</sup> complexes have been used as references
against which to compare the unique behaviors exhibited by the uranyl
(UO<sub>2</sub><sup>2+</sup>) complex, as the latter forms two distinct
solid-state structures with unusual oxo contacts to CH<sub>2</sub>Cl<sub>2</sub> and CHCl<sub>3</sub> and displays a rich electrochemical
profile that indicates a wide range of accessible metal oxidation
states through the formation of mixed-valent UÂ(VI)/UÂ(V) and UÂ(V)/UÂ(IV)
species in solution
C–H Oxidation by H<sub>2</sub>O<sub>2</sub> and O<sub>2</sub> Catalyzed by a Non-Heme Iron Complex with a Sterically Encumbered Tetradentate N‑Donor Ligand
The compound <i>N</i>,<i>N′</i>-dineopentyl-<i>N</i>,<i>N</i>′-bisÂ(2-pyridylmethyl)-1,2-ethanediamine (dnbpn) and its ferrous
complex [FeÂ(dnbpn)Â(OTf)<sub>2</sub>] were synthesized. The FeÂ(II)
complex was used to catalyze the oxidation of hydrocarbons by H<sub>2</sub>O<sub>2</sub> and O<sub>2</sub>. Although the catalyzed alkane
oxidation by H<sub>2</sub>O<sub>2</sub> displays a higher preference
for secondary over tertiary carbons than those associated with most
previously reported nonheme iron catalysts, the catalytic activity
is markedly inferior. In addition to directing the catalyzed oxidation
toward the less sterically congested C–H bonds of the substrates,
the neopentyl groups destabilize the metal-based oxidants generated
from H<sub>2</sub>O<sub>2</sub> and the FeÂ(II) complex. The presence
of benzylic substrates with weak C–H bonds stabilizes an intermediate
which we have tentatively assigned as a high-spin ferric hydroperoxide
species. The oxidant generated from O<sub>2</sub> reacts with allylic
and benzylic C–H bonds in the absence of a sacrificial reductant;
less substrate dehydrogenation is observed than with related previously
described systems that use O<sub>2</sub> as a terminal oxidant
- …