29 resultados para Alexander I, Pope, d. 115 or 6.


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New air-stable ruthenium(II) complexes that contain the aryldiamine ligand [C6H3(CH2-NMe2)(2)-2,6](-) (NCN) are described. These complexes are [RuCl{eta(2)-C,N-C6H3(CH2NMe2)(2)-2,6}(eta(6)-C10H14)] (2; C10H14 = p-cymene = C6H4Me-Pr-i-4), [Ru{eta(2)-C,N-C6H3(CH2NMe2)(2)-2,6}(eta(5)-C5H5)(PPh3)] (5), and their isomeric forms [RuCl{eta(2)-C,N-C6H3(CH2NMe2)(2)-2,4}(eta(6)-C10H14)] (3) and [Ru{eta(2)-C,N-C6H3(CH2NMe2)(2)-2,4}(eta(5)-C5H5)(PPh3)] (6), respectively. Complex 2 has been prepared from the reaction of [Li(NCN)](2) with [RuCl2(eta(6)-C10H14)](2), whereas complex 5 has been prepared by the treatment of [RuCl{eta(3)-N,C,N-C6H3(CH2NMe2)(2)-2,6}(PPh3)] (4) with [Na(C5H5)](n). Both 2 and 5 are formally 18-electron ruthenium(II) complexes in which the monoanionic potentially tridentate coordinating ligand NCN is eta(2)-C,N-bonded, In solution (halocarbon solvent at room temperature or in aromatic solvents at elevated temperature), the intramolecular rearrangements of 2 and 5 afford complexes 3 and 6, respectively. This is a result of a shift of the metal-C-aryl bond from position-1 to position-3 on the aromatic ring of the NCN ligand. The mechanism of the isomerization is proposed to involve a sequence of intramolecular oxidative addition and reductive elimination reactions of both aromatic and aliphatic C-H bonds. This is based on results from deuterium labeling, spectroscopic studies, and some kinetic experiments. The mechanism is proposed to contain fully reversible steps in the case of 5, but a nonreversible step involving oxidative addition of a methyl NCH2-H bond in the case of 2. The solid-state structures of complexes 2, 3, 5, and 6 have been determined by single-crystal X-ray diffraction. A new dinuclear 1,4-phenylene-bridged bisruthenium(II) complex, [1,4-{RuCl(eta(6)-C10H14)}(2){C-6(CH2NMe2)(4)-2,3,5,6-C,N,C',N'}] (9) has also been prepared from the dianionic ligand [C-6(CH2NMe2)(4)-2,3,5,6](2-) (C2N4). The C2N4 ligand is in an eta(2)-C,N-eta(2)-C',N'-bis(bidentate) bonding mode. Compound 9 does not isomerize in solution (halocarbon solvent), presumably because of the absence of an accessible C-aryl-H bond. Complex 9 could not be isolated in an analytically pure form, probably because of its high sensitivity to air and very low solubility, which precludes recrystallization.

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A considerable number of investigations have started to elucidate the essential roles biological agents play in the biodeterioration of stone. Chemical biocides are becoming increasingly banned because of the environmental and health hazards associated with these toxic substances. The present study reports the photodynamic effect of Methylene Blue (MB) and Nuclear Fast Red (NFR) in the presence of hydrogen peroxide (H2O2) on the destruction of the algae Chlorella vulgaris (C. vulgaris) under irradiation with visible light. Illumination of C. vulgaris in the presence of MB or NFR combined with H2O2 results in the decomposition of both the algal species and the photosensitizer. The photodynamic effect was investigated under aerobic and anaerobic conditions. Differences in mechanism type are reported and are dependent on both the presence and the absence of oxygen. The behavior of each photosensitizer leads to a Type II mechanism and a Type I/Type II combination for MB and NFR, respectively, being concluded. This novel combination could be effective for the remediation of biofilm-colonized stone surfaces.

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The present study assessed whether increased fruit and vegetable (F&V) intake reduced the concentrations of the inflammatory marker serum amyloid A (SAA) in serum, HDL2 and HDL3 and whether the latter reduction influenced any of the functional properties of these HDL subfractions. The present study utilised samples from two previous studies: (1) the FAVRIT (Fruit and Vegetable Randomised Intervention Trial) study - hypertensive subjects (systolic blood pressure (BP) range 140-190 mmHg; diastolic BP range 90-110 mmHg) were randomised to receive a 1-, 3- or 6-portion F&V/d intervention for 8 weeks, and (2) the ADIT (Ageing and Dietary Intervention Trial) study - older subjects (65-85 years) were randomised to receive a 2- or 5-portion F&V/d intervention for 1 weeks. HDL2 and HDL3 were isolated by rapid ultracentrifugation. Measurements included the following: serum high-sensitive C-reactive protein (hsCRP) by an immunoturbidimetric assay; serum IL-6 and E-selectin and serum-, HDL2- and HDL3-SAA by ELISA procedures; serum-, HDL2- and HDL3-cholesterol ester transfer protein (CETP) activity by a fluorometric assay. Although the concentrations of hsCRP, IL-6 and E-selectin were unaffected by increasing F&V intake in both studies (P>0·05 for all comparisons), those of SAA in HDL3 decreased in the FAVRIT cohort (P= 0·049) and those in HDL2 and HDL3 decreased in the ADIT cohort (P= 0·035 and 0·032), which was accompanied by a decrease in the activity of CETP in HDL3 in the FAVRIT cohort (P= 0·010) and in HDL2 in the ADIT cohort (P= 0·030). These results indicate that SAA responds to increased F&V intake, while other inflammatory markers remain unresponsive, and this leads to changes in HDL2 and HDL3, which may influence their antiatherogenic potential. Overall, the present study provides tangible evidence of the effectiveness of increased F&V intake, which may be of use to health policy makers and the general public.

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BACKGROUND: EGFR overexpression occurs in 27-55% of oesophagogastric adenocarcinomas, and correlates with poor prognosis. We aimed to assess addition of the anti-EGFR antibody panitumumab to epirubicin, oxaliplatin, and capecitabine (EOC) in patients with advanced oesophagogastric adenocarcinoma. METHODS: In this randomised, open-label phase 3 trial (REAL3), we enrolled patients with untreated, metastatic, or locally advanced oesophagogastric adenocarcinoma at 63 centres (tertiary referral centres, teaching hospitals, and district general hospitals) in the UK. Eligible patients were randomly allocated (1:1) to receive up to eight 21-day cycles of open-label EOC (epirubicin 50 mg/m(2) and oxaliplatin 130 mg/m(2) on day 1 and capecitabine 1250 mg/m(2) per day on days 1-21) or modified-dose EOC plus panitumumab (mEOC+P; epirubicin 50 mg/m(2) and oxaliplatin 100 mg/m(2) on day 1, capecitabine 1000 mg/m(2) per day on days 1-21, and panitumumab 9 mg/kg on day 1). Randomisation was blocked and stratified for centre region, extent of disease, and performance status. The primary endpoint was overall survival in the intention-to-treat population. We assessed safety in all patients who received at least one dose of study drug. After a preplanned independent data monitoring committee review in October, 2011, trial recruitment was halted and panitumumab withdrawn. Data for patients on treatment were censored at this timepoint. This study is registered with ClinicalTrials.gov, number NCT00824785. FINDINGS: Between June 2, 2008, and Oct 17, 2011, we enrolled 553 eligible patients. Median overall survival in 275 patients allocated EOC was 11.3 months (95% CI 9.6-13.0) compared with 8.8 months (7.7-9.8) in 278 patients allocated mEOC+P (hazard ratio [HR] 1.37, 95% CI 1.07-1.76; p=0.013). mEOC+P was associated with increased incidence of grade 3-4 diarrhoea (48 [17%] of 276 patients allocated mEOC+P vs 29 [11%] of 266 patients allocated EOC), rash (29 [11%] vs two [1%]), mucositis (14 [5%] vs none), and hypomagnesaemia (13 [5%] vs none) but reduced incidence of haematological toxicity (grade ≥ 3 neutropenia 35 [13%] vs 74 [28%]). INTERPRETATION: Addition of panitumumab to EOC chemotherapy does not increase overall survival and cannot be recommended for use in an unselected population with advanced oesophagogastric adenocarcinoma. FUNDING: Amgen, UK National Institute for Health Research Biomedical Research Centre.

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The t[(11;19)(p22;q23)] translocation, which gives rise to the MLL-ENL fusion protein, is commonly found in infant acute leukemias of both the myeloid and lymphoid lineage. To investigate the molecular mechanism of immortalization by MLL-ENL we established a Tet-regulatable system of MLL-ENL expression in primary hematopoietic progenitor cells. Immortalized myeloid cell lines were generated, which are dependent on continued MLL-ENL expression for their survival and proliferation. These cells either terminally differentiate or die when MLL-ENL expression is turned off with doxycycline. The expression profile of all 39 murine Hox genes was analyzed in these cells by real-time quantitative PCR. This analysis showed that loss of MLL-ENL was accompanied by a reduction in the expression of multiple Hoxa genes. By comparing these changes with Hox gene expression in cells induced to differentiate with granulocyte colony-stimulating factor, we show for the first time that reduced Hox gene expression is specific to loss of MLL-ENL and is not a consequence of differentiation. Our data also suggest that the Hox cofactor Meis-2 can substitute for Meis-1 function. Thus, MLL-ENL is required to initiate and maintain immortalization of myeloid progenitors and may contribute to leukemogenesis by aberrantly sustaining the expression of a "Hox code" consisting of Hoxa4 to Hoxa11.

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A nonlinear equation of motion is found for the dimer comprising two charged H2O molecules. The THz dielectric response to nonharmonic vibration of a nonrigid dipole, forming the hydrogen bond (HB), is found in the direction transverse to this bond. An explicit expression is derived for the autocorrelator that governs the spectrum generated by transverse vibration (TV) of such a dipole. This expression is obtained by analytical solution of the truncated set of recurrence equations. The far infrared (FIR) spectra of ice at the temperature - 7 degrees C are calculated. The wideband, in the wavenumber (frequency) v range 0... 100.0 cm(-1), spectra are obtained for liquid water at room temperature and for supercooled water at -5.6 degrees C. All spectra are represented in terms of the complex permittivity epsilon(v) and the absorption coefficient alpha(v). The obtained analytical formula for epsilon comprises the term epsilon(perpendicular to) pertinent to the studied TV mechanism with three additional terms Delta epsilon(q), Delta epsilon(mu), and epsilon(or) arising, respectively, from: elastic harmonic vibration of charged molecules along the H-bond; elastic reorientation of HB permanent dipoles; and rather free libration of permanent dipoles in 'defects' of water/ice structure. The suggested TV-dielectric relaxation mechanism allows us: (a) to remove the THz 'deficit' of loss epsilon" inherent in previous theoretical studies; (b) to explain the THz loss and absorption spectra in supercooled (SC) water; and (c) to describe, in agreement with the experiment, the low- and high-frequency tails of the two bands of ice H2O located in the range 10...300 cm(-1). Specific THz dielectric properties of SC water are ascribed to association of water molecules, revealed in our study by transverse vibration of HB charged molecules. (C) 2006 Published by Elsevier B.V.

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Full-length transient receptor potential (TRP) cation channel TRPC4alpha and shorter TRPC4beta lacking 84 amino acids in the cytosolic C terminus are expressed in smooth muscle and endothelial cells where they regulate membrane potential and Ca(2+) influx. In common with other "classical" TRPCs, TRPC4 is activated by G(q)/phospholipase C-coupled receptors, but the underlying mechanism remains elusive. Little is also known about any isoform-specific channel regulation. Here we show that TRPC4alpha but not TRPC4beta was strongly inhibited by intracellularly applied phosphatidylinositol 4,5-bisphosphate (PIP(2)). In contrast, several other phosphoinositides (PI), including PI(3,4)P(2), PI(3,5)P(2), and PI(3,4,5)P(3), had no effect or even potentiated TRPC4alpha indicating that PIP(2) inhibits TRPC4alpha in a highly selective manner. We show that PIP(2) binds to the C terminus of TRPC4alpha but not that of TRPC4beta in vitro. Its inhibitory action was dependent on the association of TRPC4alpha with actin cytoskeleton as it was prevented by cytochalasin D treatment or by the deletion of the C-terminal PDZ-binding motif (Thr-Thr-Arg-Leu) that links TRPC4 to F-actin through the sodium-hydrogen exchanger regulatory factor and ezrin. PIP(2) breakdown appears to be a required step in TRPC4alpha channel activation as PIP(2) depletion alone was insufficient for channel opening, which additionally required Ca(2+) and pertussis toxin-sensitive G(i/o) proteins. Thus, TRPC4 channels integrate a variety of G-protein-dependent stimuli, including a PIP(2)/cytoskeleton dependence reminiscent of the TRPC4-like muscarinic agonist-activated cation channels in ileal myocytes.

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Background and aims

Public health campaigns recommend increased fruit and vegetable (FV) consumption as an effective means of cardiovascular risk reduction. During an 8 week randomised control trial among hypertensive volunteers, we noted significant improvements in endothelium-dependent vasodilatation with increasing FV consumption. Circulating indices of inflammation, endothelial activation and insulin resistance are often employed as alternative surrogates for systemic arterial health. The responses of several such biomarkers to our previously described FV intervention are reported here.
Methods and results

Hypertensive volunteers were recruited from medical outpatient clinics. After a common 4 week run-in period during which FV consumption was limited to 1 portion per day, participants were randomised to 1, 3 or 6 portions daily for 8 weeks. Venous blood samples for biomarker analyses were collected during the pre and post-intervention vascular assessments. A total of 117 volunteers completed the 12 week study. Intervention-related changes in circulating levels of high sensitivity C-reactive protein (hsCRP), soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), von Willebrand factor (vWF) and plasminogen activator inhibitor-1 (PAI-1) did not differ significantly between FV groups. Similarly, there were no significant between group differences of change in homeostasis model assessment (HOMA) scores.
Conclusions

Despite mediating a significant improvement in acetylcholine induced vasodilatation, increased FV consumption did not affect a calculated measure of insulin resistance or concentrations of the circulating biomarkers measured during this study. Functional indices of arterial health such as endothelium-dependent vasomotion are likely to provide more informative cardiovascular end-points during short-term dietary intervention trials.

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Detection of Li-6 has been shown for energetic solar events, one chromospherically active binary, and several dwarf halo stars. We had previously found a Li-6/Li-7 = 0.03 +/- 0.01 for active K dwarf GJ 117 using VLT UVES observations. Here we present high signal-to-noise (> 1000) high spectral resolution observations taken with the McDonald Observatory's 2.7 m and echelle spectrometer of GJ 117. We have used the solar spectrum and template stars to eliminate possible blends, such as Ti I, in the Li-6 spectral region. Our new analysis, using an updated PHOENIX model atmosphere, finds Li-6/Li-7 = 0.05 +/- 0.02. In addition, bisector analysis showed no significant red asymmetries that would affect the lithium line profile. No changes above the statistical uncertainties are found between the VLT and McDonald data. The amount of Li-6 derived for GJ 117 is consistent with creation in spallation reactions on the stellar surface, but we caution that uncertainties in the continuum level may cause additional uncertainty in the Li-6 fraction.

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The activity and nature (i e heterogeneous and/or homogeneous) of catalysts based on CsF supported on alpha-Al2O3 were investigated for the transesterification of vegetable oil with methanol. The effect of the activation temperature, CsF loading and the reusability in a recirculating reactor were first studied CsF/alpha-Al2O3 exhibited the highest activity for a CsF loading of 0 6 mmol/g and when activated at 120 degrees C An important aspect of this study is the effect of CsF leaching into the reaction mixture, which is attributed to the high solubility of CsF in methanol, leading to a complete loss of activity after one run It was Identified that the activity of the catalyst resulted from a synergy between alumina and dissolved CsF, the presence of both compounds being absolutely necessary to observe any conversion The use of an alumina with a higher surface area resulted in a far greater reaction rate, showing that the concentration of surface site on the oxide (probably surface hydroxyl) was rate-limiting in the case of the experiments using the low surface area alpha-Al2O3 This work emphasizes that combined homogeneous-heterogeneous catalytic systems made from the blending of the respective catalysts can be used to obtain high conversion of vegetable oil to biodiesel. Despite the homogeneous/heterogeneous dual character, such a catalytic system may prove valuable in developing a simple and cost-effective continuous catalytic process for biodiesel production (C) 2010 Elsevier B V All rights reserved

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Backgroun€” Observational evidence has consistently linked increased fruit and vegetable consumption with reduced cardiovascular morbidity; however, there is little direct trial evidence to support the concept that fruit and vegetable consumption improves vascular function. This study assessed the dose-dependent effects of a fruit and vegetable intervention on arterial health in subjects with hypertension.

Methods and Results— After a 4-week run-in period during which fruit and vegetable intake was limited to 1 portion per day, participants were randomized to consume either 1, 3, or 6 portions daily for the next 8 weeks. Endothelium-dependent and -independent arterial vasodilator responses were assessed by venous occlusion plethysmography in the brachial circulation before and after intervention. Compliance was monitored with serial contemporaneous 4-day food records and by measuring concentrations of circulating dietary biomarkers. A total of 117 volunteers completed the 12-week study. Participants in the 1-, 3-, and 6-portions/d groups reported consuming on average 1.1, 3.2, and 5.6 portions of fruit and vegetables, respectively, and serum concentrations of lutein and ß-cryptoxanthin increased across the groups in a dose-dependent manner. For each 1-portion increase in reported fruit and vegetable consumption, there was a 6.2% improvement in forearm blood flow responses to intra-arterial administration of the endothelium-dependent vasodilator acetylcholine (P=0.03). There was no association between increased fruit and vegetable consumption and vasodilator responses to sodium nitroprusside, an endothelium-independent vasodilator.

Conclusions— The present study illustrates that among hypertensive volunteers, increased fruit and vegetable consumption produces significant improvements in an established marker of endothelial function and cardiovascular prognosis.

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Purpose. Keratoconus is a progressive disorder of the cornea that can lead to severe visual impairment or blindness. Although several genomic regions have been linked to rare familial forms of keratoconus, no genes have yet been definitively identified for common forms of the disease. Methods. Two genome-wide association scans were undertaken in parallel. The first used pooled DNA from an Australian cohort, followed by typing of top-ranked single-nucleotide polymorphisms (SNPs) in individual DNA samples. The second was conducted in individually genotyped patients, and controls from the USA. Tag SNPs around the hepatocyte growth factor (HGF) gene were typed in three additional replication cohorts. Serum levels of HGF protein in normal individuals were assessed with ELISA and correlated with genotype. Results. The only SNP observed to be associated in both the pooled discovery and primary replication cohort was rs1014091, located upstream of the HGF gene. The nearby SNP rs3735520 was found to be associated in the individually typed discovery cohort (P = 6.1 × 10 ). Genotyping of tag SNPs around HGF revealed association at rs3735520 and rs17501108/rs1014091 in four of the five cohorts. Meta-analysis of all five datasets together yielded suggestive P values for rs3735520 (P = 9.9 × 10 ) and rs17501108 (P = 9.9 × 10 ). In addition, SNP rs3735520 was found to be associated with serum HGF level in normal individuals (P = 0.036). Conclusions. Taken together, these results implicate genetic variation at the HGF locus with keratoconus susceptibility. © 2011 The Association for Research in Vision and Ophthalmology, Inc.

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Evidence is accumulating that vitamin D may be protective against carcinogenesis, although exceptions have been observed for some digestive tract neoplasms. The aim of the present study was to explore the association between dietary vitamin D and related nutrients and the risk of oesophageal adenocarcinoma and its precursor conditions, Barrett's oesophagus and reflux oesophagitis. In an all-Ireland case-control study conducted between March 2002 and July 2005, 218 oesophageal adenocarcinoma patients, 212 Barrett's oesophagus patients, 208 reflux oesophagitis patients and 252 population-based controls completed a 101-item FFQ, and provided lifestyle and demographic information. Multiple logistic regression analysis was applied to examine the association between dietary intake and disease risk. Oesophageal adenocarcinoma risk was significantly greater for individuals with the highest compared with the lowest tertile of vitamin D intake (OR 1·99, 95 % CI 1·03, 3·86; P for trend = 0·02). The direct association could not be attributed to a particular vitamin D food source. Vitamin D intake was unrelated to Barrett's oesophagus and reflux oesophagitis risk. No significant associations were observed for Ca or dairy intake and oesophageal adenocarcinoma, Barrett's oesophagus or reflux oesophagitis development. High vitamin D intake may increase oesophageal adenocarcinoma risk but is not related to reflux oesophagitis and Barrett's oesophagus. Ca and dairy product intake did not influence the development of these oesophageal lesions. These findings suggest that there may be population subgroups at an increased risk of oesophageal adenocarcinoma if advice to improve vitamin D intake from foods is implemented. Limited work has been conducted in this area, and further research is required.

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Background: Fruit and vegetable (FV) intake, which is often low in older people, is associated with reduced chronic disease risk. Objective: We determined whether increased FV intake improves measures of immune function. Design: We conducted a randomized controlled trial (The Ageing and Dietary Intervention Trial) in 83 healthy volunteers aged 65-85 y with low FV intakes (=2 portions/d); 82 subjects completed the intervention. Participants were assigned to continue their normal diets or to consume =5 FV portions/d for 16 wk. At 12 wk, tetanus toxoid (0.5 mL intramuscular) and Pneumovax II vaccine (0.5 mL intramuscular; both vaccines from Sanofi Pasteur) were administered. FV intake was monitored by using diet histories, and biomarkers of nutritional status were assessed. The primary endpoint was the antibody response to vaccination. Specific antibodies binding to tetanus toxoid (total IgG) and pneumococcal capsular polysaccharide (total IgG and IgG2) were assessed at baseline and 16 wk. Participants were recruited between October 2006 and June 2008. Results: The change in FV consumption differed significantly between groups [mean change in number of portions (95% CI): in the 2-portion/d group, 0.4 portions/d (0.2, 0.7 portions/d); in the 5-portion/d group, 4.6 portions/d (4.1, 5.0 portions/d); P < 0.001)] and also in micronutrient status. Antibody binding to pneumococcal capsular polysaccharide (total IgG) increased more in the 5-portion/d group than in the 2-portion/d group [geometric mean (95% CI) of the week 16:baseline ratio: 3.1 (2.1, 4.4) and 1.7 (1.3, 2.1), respectively; P = 0.005)]. There was no significant difference in the increases in antibody binding to tetanus toxoid. Conclusion: Increased FV intake improves the Pneumovax II vaccination antibody response in older people, which links an achievable dietary goal with improved immune function. This trial was registered at clinicaltrials.gov as NCT00858728. © 2012 American Society for Nutrition.