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Growing hydrogen demand and progress in fuel cell technology contributed to renewed interest in water-gas shift (WGS) reaction. Supported gold catalysts attracted a special attention during the last three decades. Given the undisputed role of support nature in catalyst activity the purpose of this work was exploration of the effect of ceria amount (1, 3, and 5 wt%) and preparation approach as sol-gel (SG) or mechanochemical mixing (MM) to WGS activity of Au/TiO 2 catalyst. Thorough studies using textural measurements, X-ray fluorescence spectrometry, powder X-ray diffraction, transmission electron microscopy, UV–Vis diffuse reflectance, UV-Raman and X-ray photoelectron spectroscopy, electron paramagnetic resonance, and temperature-programmed reduction were carried out to explain the relationship among structure, electronic properties, and WGS performance. The catalysts showed a notably better performance as compared to Ce-free Au/TiO 2 counterpart by reaching a 90−93 % CO conversion at 180 °C vs. 75 % with unmodified sample. Formation of defective Ti 4 O 7 and Ce 11 O 20 phases occurred during sample preparation by SG. In addition, a distinct ceria phase was found in MM-prepared carriers to assist preferential gold deposition. All these structures contributed to improved WGS activity of the supported gold catalysts. Activity enhancement was related to Ce–Ti interactions and modification of structural and electronic properties that favor water dissociation. New insights into structure-to-function relationships of Au/Ce–TiO 2 catalysts for WGS reaction are provided. [Display omitted] • Effect of Ce doping in Au/TiO 2 and preparation route on WGS activity was explored. • Au/Ce-doped TiO 2 outperformed Au/TiO 2 by reaching a 93 % CO conversion at 180 °C. • Defective Ti 4 O 7 and Ce 11 O 20 phases occurred during sample preparation. • Modification of structural and electronic properties favored H 2 O dissociation. • Tuning physicochemical properties of TiO 2 enable higher WGS activity of Au catalysts. [ABSTRACT FROM AUTHOR]

• Synergistic effect between components is found in most active KCoRe catalyst. • The Re4+/Re7+ ratio gives information about sour WGS activity of rhenium catalysts. • A balance between Re4+ sulphide and Re7+ oxide structures is found in KCoRe catalyst. • The KCoRe system is considered a promising sour WGS catalyst in the 250–400 °C range. Series of Re 2 O 7 /γ-Al 2 O 3 catalysts promoted with Ni, Co, and K were studied as sour gas shift catalysts. Samples were prepared by consecutive incipient wetness impregnation. Catalytic measurements were performed in a fixed bed reactor at atmospheric pressure in the range of 180–400 °C at GHSV of 4000 h−1 and steam/gas ratio of 0.3. The samples were characterised by means of N 2 physisorption, X-ray diffraction, diffuse reflectance UV–vis spectroscopy, and X-ray photoelectron spectroscopy. It was found that oxidation state ratio of rhenium sulphidic to rhenium oxygen-containing species, namely Re4+/(Re7+(+Re6+)), gives important information about redox relationship between Re4+ and Re7+ oxidation states according to additive type (K, Ni, and Co) and combinations among them. Three factors, namely, uniform deposition of K-Co-Re species on carrier surface, balance between Re sulphidic and oxidic species, and synergism among components were beneficial to the highest activity of KCoRe catalyst. This system was considered a promising catalyst for water-gas shift reaction with sulphur-containing feed in the 250–400 °C temperature range. [ABSTRACT FROM AUTHOR]

Myelofibrosis (MF) is characterized by a presence of an extra fibrous tissue in the bone marrow and additional hematopoiesis. The somatic mutation in the Janus kinase 2 (JAK2) gene (V617F) occurs gradually and is detected in about 50.0% of myelofibrosis or essential thrombo-cytopenia (ET) patients. Our aim was to determine the genotype status according to the carriers of the V617F mutation in patients with MF at the Hematology Ward of the University Hospital "Ivan Rilski" in Sofia, Bulgaria. DNA samples were isolated from venous blood of patients with various hematological disorders. DNA was amplified by polymerase chain reaction (PCR) and subsequent restriction analysis was performed using a BsaXI restriction enzyme. The genotype status was determined on 2.0% agarose gel. We analyzed 38 patients initially suspected of carrying MF or osteomyelofibrosis (OMF). After trepanobiopsy, 20 out of 38 patients were confirmed as myelofibrotic (52.6%), 5/38 (13.2%) were diagnosed as ET, 1/38 (2.6%) was diagnosed as myeloproliferative neoplasm (MPN), 6/38 (15.8%) had polycythemia vera (PV). In six patients, the presence of disease was rejected. Patients with MF were divided into three groups according to the JAK2 V617F genotype status: homozygous for the mutation (3/20 or 15.0%), heterozygous (9/20 or 45.0%) and homozygous for the wild type allele (8/20 or 40.0%). The triggering factor of MF is still unknown. It was considered that this factor could have a genetic nature. Mutations in three genes were mainly accepted as an actual predisposing events to this disease: point mutations leading to amino acid substitutions in JAK2 (V617F) and in MPL (W515L, W515K), as well as insertion or deletion in CALK We have proven that carriers of the V617F mutation prevailed in the group of patients with MF (altogether 12 patients or 60.0%). Previous studies also showed that JAK2 V617F is present in more than half of MF patients within their blood-forming cells. Therefore, the risk of evolution to MF could be associated with V617F-mutant allele burden in patients with MPN. [ABSTRACT FROM AUTHOR]

The behavioral responses of male mound-building mice Mus spicilegus to odours from males of their own species and odors from males of another species - house mouse Mus musculus musculus and yellow-necked mouse Apodemus flavicollis were studied in an attraction-avoidance test in order to clarify the role of odour in their relationships in wild populations in agricultural land. The experiments were carried out in the breeding season. M. spicilegus males showed attraction to conspecific odours from the same sex, but indifference to heterospecific odours of male M. m. musculus, and avoidance to odours of male A. flavicollis. The behavioural responses to conspecific and heterospecific odours are discussed in terms of attractiveness of odour cues, according to their significance in social relationships and spacing behaviour. [ABSTRACT FROM AUTHOR]

A specific preparation method for depositing W oxo-species and modification with potassium have been applied to study physicochemical features and activity behaviour of a NiW/Al 2 O 3 system as a sulphur-tolerant water–gas shift catalyst. Equilibrium deposition filtration and conventional wet impregnation were used for W loading on alumina surface. Nickel and potassium deposition was carried out following incipient wetness impregnation. Catalytic measurements were performed in a fixed bed reactor at atmospheric pressure in the range of 250–400 °C. Samples were characterised by means of N 2 physisorption, X-ray diffraction, Raman, diffuse reflectance UV–vis-NIR, and XP spectroscopies. A combination between the equilibrium deposition-filtration method for tungsten deposition and potassium modification of NiW catalysts gives rise to increased tungsten dispersion of calcined and tested samples. This has led to enhanced reducibility/sulphidability, improved stability of the metal–sulphur bond at the surface, and a higher activity of the KNiW catalysts for the water–gas shift reaction in sulphur-containing gas mixtures. [ABSTRACT FROM AUTHOR]

Highlights: [•] The components do not strongly change the primary mesoporous texture of γ-Al2O3. [•] The nature and bond strength of the oxide precursors generate different S species. [•] Both tungsten reducibility and sulphur stability to oxidation determine the activity. [•] The KNiW system exhibits both features to moderate extent and the highest activity. [ABSTRACT FROM AUTHOR]

The dispersion relations for surface plasmon polaritons propagating in the Voigt geometry in a metal-insulator-metal waveguide with a magneto-optically active dielectric medium are derived. The symmetry between the upper and lower interfaces is broken by the introduction of the magnetic field; the balance between the field distributions on the two interfaces can be controlled by the applied field. This control is illustrated by finite-element method numerical simulations of the field distributions around a point dipole placed in the center of the short waveguide; it is shown that both the total emission of radiation from the cavity and the distribution of the far-field radiation can be strongly modified by tuning the magnetization of the waveguide. This raises the possibility of using magnetic fields to control light propagation in nanostructures. [ABSTRACT FROM AUTHOR]

Abstract: Crust of carbonate minerals, named calcrete, underlies the arable soils of Southeast Bulgaria. The basic microorganism groups from soil, developed on top of a massive calcrete and in the rhizosphere of Cichorium intybus (Common chicory) were estimated by culturable methods. In this plant''s rhizosphere, microorganisms from some physiological groups were found in numbers 1 to 3 orders of magnitude higher, compared to non-rhizosphere samples of massive calcrete. The dominant microorganisms in this plant''s rhizosphere are represented by genera Bacillus. 16S rRNA gene nucleotide sequences were used for identification of four strains, obtained from the rhizospheres of C. intybus. The sequences obtained were compared to those of Bacillus species held in GenBank. The strains CI R1 and CI R3 were found to belong to the species Bacillus subtilis and the strains CI R2 and CI R4 to the species Bacillus amyloliquefaciens. Numerous studies confirm that these species are good facilitators of plant growth in nutrient deficient carbonate environment. Study of the growth‐promoting potential of these bacterial species, for economically important plants cultivated in this region, is currently in progress. [Copyright &y& Elsevier]

In this study the problem of reduction of energy consumption in bioreactors system of antibiotics production by means of energy integration is considered. An energy integration scheme with two heat storage tanks ensuring the system operation at different time intervals is proposed. An approach for processes management of energy integration is developed. The problem is formulated in the terms of MINLP. The efficiency of proposed approach is illustrated on the example of the industry. [ABSTRACT FROM AUTHOR]

Few years ago the effectiveness of different Lactobacillus strains, with activity against different pathogens, was intensively studied. In particular, by producing metabolites such as acetic and lactic acid and thus lowering the pH, Lactobacillus strains inhibit the growth of bacterial pathogens and sometimes even kill them. In this study were included original Bulgarian dairy lactobacilli. The antibacterial activity against 8 test cultures and 8 clinical isolates was estimated by the agar diffusion method. We observed the inhibitory effect of growth of Bacillus subtilis, Bacillus alvei, Escherishia coli and Pseudomonas aeruginosa strains. The cells-free exponential cultures of non-neutralized (pH 3.9) and neutralized forms of the strain Lactobacillus sp. 50P1 showed highest activity. The active strain was identified as L. helveticus by classical and biochemical tests (API LAB 50CH kit). In addition to some technologically relevant properties the active strain 50P1 showed strong antibacterial effect against clinically isolated Pseudomonas aeruginosa and Bacillus alvei - an agricultural important bee pathogen. In conclusion, our results will form the basis for additional studies and possible further application of characterized L. helveticus 50P1 strain in clinical practice and/or veterinary medicine. [ABSTRACT FROM AUTHOR]

Background The evidence on whether antioxidant supplements prevent gastrointestinal cancers is contradictory. Aim To assess the beneficial and harmful effects of antioxidant supplements in preventing gastrointestinal cancers. Methods Using the Cochrane Collaboration methodology, we reviewed the randomized trials comparing antioxidant supplements with placebo or no intervention on the occurrence of gastrointestinal cancers. We searched electronic databases and reference lists until October, 2007. Our outcome measures were gastrointestinal cancers, overall mortality and adverse events. Outcomes were reported as relative risks (RR) with 95% confidence intervals (CI) based on random-effects and fixed-effect models meta-analyses. Results We identified 20 randomized trials (211 818 participants) assessing beta-carotene, vitamin A, vitamin C, vitamin E, and selenium. The trial quality was generally high. The antioxidant supplements were without a significant effect on the occurrence of gastrointestinal cancers (RR 0.94, 95% CI 0.83–1.06, I 2 = 54.0%). The heterogeneity seemed to be explained by bias risk (low-bias risk trials RR 1.04, 95% CI 0.96–1.13 compared to high-bias risk trials RR 0.59, 95% CI 0.43–0.80, test of interaction P < 0.0005) and type of antioxidant supplement (beta-carotene potentially increasing and selenium potentially decreasing cancer risk). Antioxidant supplements had no significant effect on mortality in a random-effects model meta-analysis (RR 1.02, 95% CI 0.97–1.07, I 2 = 53.5%) but significantly increased mortality in a fixed-effect model meta-analysis (RR 1.04, 95% CI 1.02–1.07). Conclusions We could not find evidence that the studied antioxidant supplements prevented gastrointestinal cancers. On the contrary, they seem to increase overall mortality. [ABSTRACT FROM AUTHOR]

Abstract: One-component samples containing K, Ni, and various concentrations of Mo were prepared by incipient wetness impregnation technique. Bi- and tri- component samples have been prepared from the calcined one- and bi-component samples following the same procedure. The samples were characterized by SSA, FT-IR, DRS and Raman measurements. The decrease of the ratio Ni2+(Td)/Ni2+(Oh) with the increase of Mo loading and the re-dispersion of Mo phase after the Ni addition on the one-component Mo containing samples proved the occurrence of interactions between these components in the bi-component NiMo-containing samples. Most probably Ni–Mo–O surface species with different number of Mo-oxo and Ni-oxo entities are formed, depending on the Ni/Mo atomic ratio. It may be accepted, that the Ni2+ ions are partially localized into the molybdate layer without forming well-defined phases. Two kinds of K+ ions have been determined in the corresponding samples, interacting (“bounded” K+ ions) and not interacting (“free” K+ ions) with the rest of the supported phases. The potassium deposition increased the dispersion of Mo phase and influenced the coordination state of the Mo6+ and Ni2+ ions in the bi-component KMo-, KNi-containing samples and the tri-component KNiMo-containing samples. It provoked partial transformation of the polymeric Mo6+(Oh) species into monomeric Mo6+(Td) ones and Ni2+(Td) species predomination over Ni2+(Oh) ones. Most probably, new complex K–Ni–Mo–O species were formed on the support surface in the case of the tri-component samples. [Copyright &y& Elsevier]

Context: Antioxidant supplements are used for prevention of several diseases.Objective: To assess the effect of antioxidant supplements on mortality in randomized primary and secondary prevention trials. DATA SOURCES AND TRIAL SELECTION: We searched electronic databases and bibliographies published by October 2005. All randomized trials involving adults comparing beta carotene, vitamin A, vitamin C (ascorbic acid), vitamin E, and selenium either singly or combined vs placebo or vs no intervention were included in our analysis. Randomization, blinding, and follow-up were considered markers of bias in the included trials. The effect of antioxidant supplements on all-cause mortality was analyzed with random-effects meta-analyses and reported as relative risk (RR) with 95% confidence intervals (CIs). Meta-regression was used to assess the effect of covariates across the trials.Data Extraction: We included 68 randomized trials with 232 606 participants (385 publications).Data Synthesis: When all low- and high-bias risk trials of antioxidant supplements were pooled together there was no significant effect on mortality (RR, 1.02; 95% CI, 0.98-1.06). Multivariate meta-regression analyses showed that low-bias risk trials (RR, 1.16; 95% CI, 1.04[corrected]-1.29) and selenium (RR, 0.998; 95% CI, 0.997-0.9995) were significantly associated with mortality. In 47 low-bias trials with 180 938 participants, the antioxidant supplements significantly increased mortality (RR, 1.05; 95% CI, 1.02-1.08). In low-bias risk trials, after exclusion of selenium trials, beta carotene (RR, 1.07; 95% CI, 1.02-1.11), vitamin A (RR, 1.16; 95% CI, 1.10-1.24), and vitamin E (RR, 1.04; 95% CI, 1.01-1.07), singly or combined, significantly increased mortality. Vitamin C and selenium had no significant effect on mortality.Conclusions: Treatment with beta carotene, vitamin A, and vitamin E may increase mortality. The potential roles of vitamin C and selenium on mortality need further study. [ABSTRACT FROM AUTHOR]

Abstract: The changes in the corrosion characteristics of stainless steel OC4004 in 0.1M HNO3 after electrodeposition of thin Al and Ce oxide films on it has been investigated. The Ce2O3–CeO2 layers have been found to possess a pronounced stabilizing effect on the steel passive state and on its corrosion resistance, respectively, whereas the Al2O3 layers do not improve considerably the corrosion behaviour of the SS/Al2O3 system. A twice-lower corrosion current was observed with a ternary SS/Al2O3/Ce2O3–CeO2 system in the passive region, while the zones of potentials, where the steel is in a stable passive state, are not changed. The obtained results permit the assumption that the cerium oxides layer acts as an effective cathode playing a determining role with respect to the improvement of the corrosion behavior of the steel. It has been concluded that when the SS/Al2O3/Ce2O3–CeO2 system is used in media containing nitric acid, the corrosion will proceed at potentials where the passive state of steel would not be disturbed. [Copyright &y& Elsevier]

Abstract: Investigations have been carried out on the changes in the corrosion behaviour of OC4004 stainless steel protected by an electrochemically deposited Ce2O3–CeO2 film. It may be assumed, on the basis of the obtained results, that in addition to exercising a screening effect, the cerium oxides film plays the role of an effective cathode stabilizing the steel passive state, i.e. its corrosion resistance without changing the zones of potentials where the steel is in a stable passive state. It has been concluded that in the cases when the Ce2O3–CeO2-protected stainless steel will be used as a construction material for catalytic converters designed for purification of nitric acid containing emissions, the corrosion will proceed at potentials, where the steel passive state will not be disturbed. Simultaneously, the presence of the Ce2O3–CeO2 coverage screens the accumulation on the SS/Ce2O3–CeO2 surface of iron/iron oxides and hydroxides, which could have a negative effect (as catalyst poisons), on the desired catalytic process. [Copyright &y& Elsevier]

The Wnt signaling pathway is activated by mutations in the adenomatous polyposis coli (APC) or β-catenin genes in most colon cancers, leading to the transactivation of promoters containing binding sites for the Tcf/LEF family of transcription factors. We have previously shown that it is possible to confer colon cancer specificity on autonomous parvoviruses by inserting Tcf sites into the viral P4 promoter. The mutant Tcf promoters were responsive to activation of the Wnt pathway but the viruses replicated poorly. We show here that reduction of the number of Tcf sites from four to two leads to an increase in the efficiency of replication and toxicity of the viruses in Co115 colon cancer cells, with only a small reduction in selectivity for cells with an active Wnt signaling pathway. Despite this improvement, virus production by most colon cancer cells remained low. Analysis of parental phH1 virus infection of SW480 colon cancer cells showed that the nonstructural and capsid proteins were expressed, but single stranded DNA and progeny virus were not produced. This defect reflects the dependence of autonomous parvoviruses on host functions for many steps in their replication cycle and represents a major limitation to the use of selectively replicating parvoviruses for colon cancer therapy.Cancer Gene Therapy (2006) 13, 273–280. doi:10.1038/sj.cgt.7700904; published online 9 September 2005 [ABSTRACT FROM AUTHOR]

Abstract: The one-, bi- and tri-component (K)(Ni)(Mo)/γ-Al2O3 systems are studied after water–gas shift reaction tests in the presence of sulfur in the feed. The samples are characterized after the calcination procedure (oxidic state) and after the catalytic activity test (tested state) by SSA, XRD, XPS and EPR measurements. The Mo4+, Mo5+ and Mo6+ oxidation states are registered on the surface of the tested samples. The different sulfur species such as: sulfide sulfur, oxysulfides, polysulfides, paramagnetic sulfur and sulfate sulfur are present on the sample surface in the reaction redox environment (CO, H2O, H2S, H2 and CO2 agents). The XPS and EPR characterization of the tested state points to the idea that both the molybdenum reducibility (i.e. the Mo4+/(Mo5+ +Mo6+) and Mo4+/Mo5+ ratios) and the sulfur lability (sulfide/sulfate ratio) represent informative indices in regard to the catalytic properties of the Mo-containing systems in the WGS reaction in case of sulfur presence in the feed mixture. [Copyright &y& Elsevier]

Background The progression of hepatic fibrosis into cirrhosis is a main prognostic factor for survival in people with alcoholic liver disease. The range of cut-off values characterising the stage of hepatic fibrosis seems to be dependent on the aetiology of the liver disease. Aims To determine the diagnostic accuracy of transient elastography (the index test) for diagnosis of fibrosis in alcoholic liver disease when compared with liver biopsy (the reference standard), using the METAVIR scoring system. To establish the optimal cut-off values for the hepatic fibrosis stages. Methods We followed Cochrane Methodology for diagnostic test accuracy reviews. We identified 14 studies. Among the study participants with alcoholic liver disease, 834 provided numerical data for analysis (August 2014). Only half of the studies were monoaetiology studies. We used the bivariate model and estimated the summary sensitivities and summary specificities. Hence, we calculated the summary likelihood ratios ( LRs) to rule in or rule out hepatic fibrosis. We investigated pre-defined sources of heterogeneity. Results Severe fibrosis (F3 or worse): summary (95% CI) sensitivity 0.92(0.89-0.96) and specificity 0.70(0.61-0.79); LR+ 3.1(2.1-4.1), LR− 0.11(95% CI 0.06-0.16). Cirrhosis (F4): summary (95% CI) sensitivity of 0.95(0.87-0.98) and specificity 0.71(0.56-0.82); LR+ 3.3(2.1-5.0); LR− 0.07(0.03-0.19). Conclusions Transient elastography may be used as a diagnostic method to exclude cirrhosis or severe fibrosis when the test is negative. Cut-off values of around 12.5 kPa for cirrhosis may be used in clinical practice, but caution is needed, as the values reported in the review are not yet prospectively validated. [ABSTRACT FROM AUTHOR]

Epigenetic changes, in particular DNA methylation processes, play a role in the pathogenesis and progression of type 2 diabetes mellitus (T2DM) linking genetic and environmental factors. To clarify this role, we have analyzed in patients with different duration of T2DM: (i) expression levels of methyl- CpG-binding domain protein 2 (MBD2) as marker of DNA methylation, and ii) methylation changes in 22 genes connected to cellular stress and toxicity. We have analyzed MBD2 mRNA expression levels in 16 patients and 12 controls and the methylation status of stress and toxicity genes in four DNA pools: (i) controls; (ii) newly-diagnosed T2DM patients; (iii) patients with T2DM duration of <5 years and (iv) of >5 years. The MBD2 expression levels were 10.4-times increased on average in T2DM patients compared to controls. Consistent increase in DNA methylation fraction with the increase in T2DM duration was observed in Prdx2 and SCARA3 genes, connected to oxidative stress protection and in BRCA1 and Tp53 tumor-suppressor genes. In conclusion, increased MBD2 expression in patients indicated general dysregulation of DNA methylation in T2DM. The elevated methylation of Prdx2 and SCARA3 genes suggests disturbance in oxidative stress protection in T2DM. The increased methylation of BRCA1 and Tp53 genes unraveled an epigenetic cause for T2DM related increase in cancer risk. [ABSTRACT FROM AUTHOR]

This paper is treating the problem of reducing energy consumption through heat integration system of bioreactors for antibiotics production. A scheme for heat integration with two heat tanks providing work in different time intervals is proposed. A practically feasible method for managing the processes of heat integration is designed. The task is formulated in terms of continuous nonlinear programming (NLP). The method has been applied to a real industrial process for the production of antibiotics. [ABSTRACT FROM AUTHOR]

Aliment Pharmacol Ther 2010; 32: 356–367 Background Several liver diseases have been associated with oxidative stress. Accordingly, antioxidants have been suggested as potential therapeutics for various liver diseases. The evidence supporting these suggestions is equivocal. Aim To assess the benefits and harms of antioxidant supplements for patients with liver diseases. Methods We identified trials through electronic and manual searches until August 2009. We included randomized trials comparing antioxidant supplements (beta-carotene, vitamin A, C, E and selenium) vs. placebo or no intervention for autoimmune liver diseases, viral hepatitis, alcoholic liver disease and cirrhosis (any aetiology). Random-effects and fixed-effect meta-analyses were conducted. Results were presented as relative risks (RR), or mean difference (MD), both with 95% confidence intervals (CI). Results Twenty randomized trials with 1225 participants were included. The trials assessed beta-carotene (3 trials), vitamin A (2 trials), vitamin C (9 trials), vitamin E (15 trials) and selenium (8 trials). The majority of the trials had high risk of bias and showed heterogeneity. Overall, the assessed antioxidant supplements had no significant effect on all-cause mortality [relative risk (RR) 0.84, 95% confidence interval (CI) 0.60–1.19, I2 = 0%] or liver-related mortality (RR 0.89, 95% CI 0.39–2.05, I2 = 37%). Stratification according to the type of liver disease assessed did not affect the conclusions. Antioxidant supplements significantly increased the activity of gamma glutamyl transpeptidase (MD 24.21 IU/L, 95% CI 6.67–41.75, I2 = 0%). Conclusions We found no evidence to support or refute antioxidant supplements in patients with liver disease. Antioxidant supplements may increase liver enzymes. [ABSTRACT FROM AUTHOR]

The article focuses on the efficiency of practicing meta-analysis of randomized clinical trials (RCTs) in detecting patients' diseases in Great Britain. Conducting meta-analysis is important because it determines whether patients were able to receive the appropriate medical care. The randomization and binding process derived from Cochrane Hepato-Biliary module was used in assessing patient's treatment.

Tumor-suppressor Pdcd4 inhibits transformation and invasion and is downregulated in cancers. So far, it has not been studied as to whether miRNAs, suppressing target expression by binding to the 3′-UTR, regulate Pdcd4 or invasion. The present study was conducted to investigate the regulation of Pdcd4, and invasion/intra-vasation, by miRNAs. A bioinformatics search revealed a conserved target-site for miR-21 within the Pdcd4-3′-UTR at 228–249 nt. In 10 colorectal cell lines, an inverse correlation of miR-21 and Pdcd4-protein was observed. Transfection of Colo206f-cells with miR-21 significantly suppressed a luciferase-reporter containing the Pdcd4-3′-UTR, whereas transfection of RKO with anti-miR-21 increased activity of this construct. This was abolished when a construct mutated at the miR-21/nt228–249 target site was used instead. Anti-miR-21-transfected RKO cells showed an increase of Pdcd4-protein and reduced invasion. Moreover, these cells showed reduced intra-vasation and lung metastasis in a chicken–embryo–metastasis assay. In contrast, overexpression of miR-21 in Colo206f significantly reduced Pdcd4-protein amounts and increased invasion, while Pdcd4-mRNA was unaltered. Resected normal/tumor tissues of 22 colorectal cancer patients demonstrated an inverse correlation between miR-21 and Pdcd4-protein. This is the first study to show that Pdcd4 is negatively regulated by miR-21. Furthermore, it is the first report to demonstrate that miR-21 induces invasion/intravasation/metastasis.Oncogene (2008) 27, 2128–2136; doi:10.1038/sj.onc.1210856; published online 29 October 2007 [ABSTRACT FROM AUTHOR]

Background Colorectal cancer may be prevented by reducing the development of adenomatous polyps. Aim To assess the benefits and harms of antioxidant supplements in preventing colorectal adenoma. Methods Using the Cochrane Collaboration methodology we reviewed all randomized clinical trials comparing antioxidant supplements with placebo or no intervention. We searched electronic databases and the reference lists until October 2005. Outcome measures were development of colorectal adenoma adverse events. We analysed dichotomous outcomes with fixed- and random-effects model meta-analyses and calculated the relative risk with 95% confidence interval. Results We identified eight randomized trials (17 620 participants). Neither fixed-effect (relative risk: 0.93, 95% CI: 0.81–1.1) nor random-effect model meta-analyses (0.82, 0.60–1.1) showed statistically significant effects of supplementation with β-carotene, vitamins A, C, E and selenium alone or in combination. Antioxidant supplements seemed to increase the development of colorectal adenoma in three low-bias risk trials (1.2, 0.99–1.4) and significantly decrease its development in five high-bias risk trials (0.59, 0.47–0.74). The estimates difference is significant ( P < 0.0001). There was no significant difference between the intervention groups regarding adverse events, including mortality (0.82, 0.47–1.4). Conclusion We found no convincing evidence that antioxidant supplements have significant beneficial effect on primary or secondary prevention of colorectal adenoma. [ABSTRACT FROM AUTHOR]

This work presents a new electrochemical method (i.e. new electrolyte composition and electrolysis regimes) for direct formation of Al2O3 on different metal substrates from non-aqueous electrolytes, data on the kinetics of the electrochemical processes and scanning electron microscopy (SEM) and XPS studies of the morphology, structure, dispersion and chemical composition of deposited Al2O3. [Copyright &y& Elsevier]

We study two-variable Engel-like relations and identities characterizing finite-dimensional solvable Lie algebras and, conjecturally, finite solvable groups and introduce some invariants of finite groups associated with such relations. Bibliography: 29 titles. [ABSTRACT FROM AUTHOR]

The authors discuss their response on the comments regarding their article on transient elastography for staging liver fibrosis in alcoholic liver disease. They agree that their article is based on their Cochrane systematic review but stress that including data from the two studies will not influence the results of the meta-analyses. They argue against the comment that the mixed aetiology in the 50% of the included studies is a limitation of their review.

Mutations in the receptor of the epidermal growth factor receptor (EGFR) in non-small cell lung cancer (NSCLC) are used as biomarkers for predicting the response of treatment with EGFR tyrosine kinase inhibitors (EGFR TKIs). Non-small cell lung cancer patients usually have activating EGFR mutations that leads to a very good response when they are treated with EGFR TKIs. Our tumor samples were examined for the presence of sensitive mutations in the EGFR gene, resistant mutations or the absence of mutations. To identify the types of the mutation, we used a real-time polymerase chain reaction (RT-PCR) method. Additionally, we evaluated the frequency of EGFR mutations and their association with smoking status, gender and histology. The tumor samples (n = 551) were tested for 29 somatic mutations in the EGFR gene. Sensitive mutations in the EGFR genes were found in 55 NSCLC samples (10.0%). The prevalence of EGFR mutations was much higher for females than for males (27.1 vs. 3.9%, p <0.001). The prevalence of EGFR mutations was greater in subjects who had never smoked than in smokers (15.0 vs. 6.08%, p <0.003). Additionally, the frequency of EGFR mutations was higher in adenocarcinomas than in other histological types (14.9 vs. 5.1%; p <0.001). Our results show that activating mutations on the EGFR gene are more frequent in females than in males, in adenocarcinoma than other histological types and in non smokers than smokers. [ABSTRACT FROM AUTHOR]

A response by the G. Bjelakovic and colleagues to a letter to the editor on their article "Metaanalysis: antioxidant supplements for liver disease: the Cochrane Hepato-Biliary Group" in the 2010 issue is presented.

Sunflower oil hydrogenation process was studied on silica supported nickel catalysts. Three texturally different silica gel materials were used as supports for synthesis of Ni/Si02 catalyst precursors. After precursors' reduction and paraffin oil impregnation, obtained catalysts were used in sunflower oil hydrogenation reaction. For catalytic test, a new type of catalyst feeder was constructed and presented. The hydrogenation activity of catalysts was monitored through the decrease of refractive index and hydrogen consumption. A correlation between iodine value, refractive index and hydrogen consumption was established. The reaction rate constants were obtained from fatty acid composition of partially hydrogenated oil and further studied for the investigation of possible reaction pathways. Kinetics and mechanisms were evaluated and tested with the aim to reduce the number of reactions participating in the reaction scheme. A set of ordinary differential equations, corresponding to the investigated model, was solved numerically by Gear' s algorithm. It was shown that a number of significant reactions in a model depend on the activity of catalysts. More active catalyst results in more reaction pathways and more side chemical reactions. [ABSTRACT FROM AUTHOR]

The article focuses on understanding the influence of the anthropomorphic thinking of Bulgarian children on their conceptions of the natural world. The authors aim to determine the dynamics of the conceptions of pre-school and primary school children. They state that there are differences in the literary images of plants and animals by the scientific description with children.