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Graphical abstract Highlights • New TS-1-derived catalysts were synthesized. • Their catalytic activity towards methyl(phenyl)sulfide S -oxidation was investigated. • Selectivity and progress of reaction have been observed under various conditions. • According to the gathered data a dual catalysis pathway have been proposed. Abstract Titanium-containing zeolite-based catalysts have been synthesized and investigated as catalysts in methyl(phenyl)sulfide oxidation with hydrogen peroxide. A hierarchical TS-1 prepared by the secondary templating and a layered TS-1 without and with silica and silica-titania pillars have been studied. Conventional TS-1 was a benchmarking material. The study focuses on observation of the different catalytic performance with regard to textural properties; presence and volume of mesopores and different diffusion characteristics. Thus, a deficiency and excess of the oxidizing agent were used in the catalysed reactions and the progress of reaction and selectivity to products were studied. All tested catalysts have shown after 240 min almost total conversion of methyl(phenyl)sulfide with different selectivity (substrate/catalyst mass ratio 10). It was observed that the reactants ratio hydrogen peroxide/ methyl(phenyl)sulfide influences the selectivity to sulfoxide or sulfone over a particular catalyst. In the case of hydrogen peroxide deficiency experiments (H 2 O 2 /sulfide = 0.5 mol/mol) the catalysts exhibited different distributions of products. Lamellar catalyst provided 100% selectivity to sulfoxide, the others in range of 90–65% selectivity to sulfoxide; however, the selectivity was independent on the reaction time and substrate conversion. In the case of the excess of the oxidant, except for Ti-pillared TS-1, all the catalysts showed stabile selectivity of 65% towards methyl(phenyl)sulfoxide being independent of the catalyst. The Ti-pillared TS-1 has shown, during the reaction progress, a decrease in the selectivity to sulfoxide from initial 60% to final 20% of sulfoxide at almost total conversion. The only case when higher selectivity to sulfone was achieved was gradual dosing of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Background: Data on the efficacy and safety of long-term vitamin D supplementation in chronic kidney disease (CKD) are scarce. We assessed the effects of the 12-month vitamin D3 treatment on mineral metabolism and calciotropic hormones in patients with CKD stages 2–4. Methods: Eighty-seven patients (mean age 66 years, men/women 33/54) were randomized to cholecalciferol treatment with either 5,000 or 20,000 IU/week. Serum calcium, phosphate, 25(OH)D3, 1,25(OH)2D3, PTH and urinary mineral concentrations were obtained at baseline and after 4, 8 and 12 months. Results: The median serum mineral concentrations were normal and not changed throughout the study. The number of hypercalciuric patients slightly increased with higher dose, but no sustained rise in calciuria was present. Vitamin D insufficiency/deficiency was revealed in 72 (83%) patients at baseline and 37 (43%) at month 12. The 25(OH)D3 levels increased more with higher dose; a rise in 1,25(OH)2D3 was less impressive. The parathyroid hormone (PTH) concentrations were reduced, but the number of subjects with PTH below the lower limit for CKD stage 3 increased equally with both doses. Conclusions: Vitamin D insufficiency/deficiency in CKD significantly improved after the 12-month cholecalciferol treatment, with higher dose being more effective and equally safe. Further studies of vitamin D3 effects on bone metabolism are warranted. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The recent expansion of the field of RNA chemical modifications has changed our understanding of post‐transcriptional gene regulation. Apart from internal nucleobase modifications, 7‐methylguanosine was long thought to be the only eukaryotic RNA cap. However, the discovery of non‐canonical RNA caps in eukaryotes revealed a new niche of previously undetected RNA chemical modifications. We are the first to report the existence of a new non‐canonical RNA cap, diadenosine tetraphosphate (Ap4A), in human and rat cell lines. Ap4A is the most abundant dinucleoside polyphosphate in eukaryotic cells and can be incorporated into RNA by RNA polymerases as a non‐canonical initiating nucleotide (NCIN). Using liquid chromatography‐mass spectrometry (LC–MS), we show that the amount of capped Ap4A‐RNA is independent of the cellular concentration of Ap4A. A decapping enzyme screen identifies two enzymes cleaving Ap4A‐RNA,NUDT2 and DXO, both of which also cleave other substrate RNAs in vitro. We further assess the translatability and immunogenicity of Ap4A‐RNA and show that although it is not translated, Ap4A‐RNA is recognized as self by the cell and does not elicit an immune response, making it a natural component of the transcriptome. Our findings open a previously unexplored area of eukaryotic RNA regulation. [ABSTRACT FROM AUTHOR]

The recent expansion of the field of RNA chemical modifications has changed our understanding of post‐transcriptional gene regulation. Apart from internal nucleobase modifications, 7‐methylguanosine was long thought to be the only eukaryotic RNA cap. However, the discovery of non‐canonical RNA caps in eukaryotes revealed a new niche of previously undetected RNA chemical modifications. We are the first to report the existence of a new non‐canonical RNA cap, diadenosine tetraphosphate (Ap4A), in human and rat cell lines. Ap4A is the most abundant dinucleoside polyphosphate in eukaryotic cells and can be incorporated into RNA by RNA polymerases as a non‐canonical initiating nucleotide (NCIN). Using liquid chromatography‐mass spectrometry (LC–MS), we show that the amount of capped Ap4A‐RNA is independent of the cellular concentration of Ap4A. A decapping enzyme screen identifies two enzymes cleaving Ap4A‐RNA,NUDT2 and DXO, both of which also cleave other substrate RNAs in vitro. We further assess the translatability and immunogenicity of Ap4A‐RNA and show that although it is not translated, Ap4A‐RNA is recognized as self by the cell and does not elicit an immune response, making it a natural component of the transcriptome. Our findings open a previously unexplored area of eukaryotic RNA regulation. [ABSTRACT FROM AUTHOR]

A long-term vegetarian diet is generally poor in vitamin B group. The lack of vitamin B12 together with vitamin B6 and folate deficiency is closely related to homocysteine metabolism. Hyperhomocysteinemia was found to be associated with increased bone turnover markers and increased fracture risk. Thus, hyperhomocysteinemia, vitamin B12 and folate deficiency may be regarded as novel risk factors for micronutrient deficiency-related osteoporosis. To assess the possible impact of a vegetarian diet on bone mineral density in cohort of Slovak vegetarian women. Fasting serum glucose, albumin, calcium, phosphorous and creatinine as well as bone markers, serum vitamin B12, folate and plasma levels of total homocysteine were assessed in two nutritional groups (vegetarians vs. nonvegetarians) of apparently healthy women (age range 20–70 years). Bone mineral density of the femoral neck, trochanter, total femur and lumbar spine was measured in all subjects. Vegetarians had a significantly lower weight ( p < 0.05), higher PTH ( p < 0.01) and homocysteine ( p < 0.001). Vitamin B12 was significantly higher in nonvegetarians ( p < 0.001). No differences were observed in folate levels. Univariate analysis showed significant association between homocysteine and B12 ( p < 0.01), folate ( p < 0.001), creatinine ( p < 0.001), total proteins ( p < 0.049), age ( p < 0.001) and vegetarian food intake ( p < 0.001). Vegetarians had a significantly lower TrFBMD ( p < 0.05) and ToFBMD ( p < 0.05). Age and CTx were significant predictors in all sites of measured BMD and PTH. A strong correlation between homocysteine and FNBMD ( r = −0.2009, p < 0.002), TrFBMD ( r = −0.1810, p < 0.004) and ToFBMD ( r = −0.2225, p < 0.001) was found in all subjects. Homocysteine is one of the predictors of bone mineral density, and hyperhomocysteinemia is associated with lower bone mineral density. In healthy adults, homocysteine levels are dependent on age as well as on nutritional habits. Thus, elderly women on a vegetarian diet seem to be at higher risk of osteoporosis development than nonvegetarian women. [ABSTRACT FROM AUTHOR]

The GRACE (GMO Risk Assessment and Communication of Evidence; ) project was funded by the European Commission within the 7th Framework Programme. A key objective of GRACE was to conduct 90-day animal feeding trials, animal studies with an extended time frame as well as analytical, in vitro and in silico studies on genetically modified (GM) maize in order to comparatively evaluate their use in GM plant risk assessment. In the present study, the results of a 1-year feeding trial with a GM maize MON810 variety, its near-isogenic non-GM comparator and an additional conventional maize variety are presented. The feeding trials were performed by taking into account the guidance for such studies published by the EFSA Scientific Committee in 2011 and the OECD Test Guideline 452. The results obtained show that the MON810 maize at a level of up to 33 % in the diet did not induce adverse effects in male and female Wistar Han RCC rats after a chronic exposure. [ABSTRACT FROM AUTHOR]

The GMO Risk Assessment and Communication of Evidence (GRACE; ) project is funded by the European Commission within the 7th Framework Programme. A key objective of GRACE is to conduct 90-day animal feeding trials, animal studies with an extended time frame as well as analytical, in vitro and in silico studies on genetically modified (GM) maize in order to comparatively evaluate their use in GM plant risk assessment. In the present study, the results of two 90-day feeding trials with two different GM maize MON810 varieties, their near-isogenic non-GM varieties and four additional conventional maize varieties are presented. The feeding trials were performed by taking into account the guidance for such studies published by the EFSA Scientific Committee in 2011 and the OECD Test Guideline 408. The results obtained show that the MON810 maize at a level of up to 33 % in the diet did not induce adverse effects in male and female Wistar Han RCC rats after subchronic exposure, independently of the two different genetic backgrounds of the event. [ABSTRACT FROM AUTHOR]

We have addressed the question whether the relatively high incidence of cardiovascular disease and certain cancers in countries of central/eastern Europe might be associated with nutritional imbalance, in particular a lack of fresh fruit and vegetables in the diet in winter months. Nutritional parameters and markers of oxidative stress were studied in three Slovak population groups: 46 survivors of myocardial infarction (MI group) and 48 healthy, normolipidemic subjects (NL), living in or near Bratislava; and 70 rural controls (RC group) living a more traditional life style in a country town. Data were collected in February/March and September/October of two consecutive years, representing times of minimum and maximum local availability of fresh fruits and vegetables. Oxidative stress was monitored using two biomarkers; plasma malondialdehyde (MDA, a product of lipid peroxidation), and oxidation of lymphocyte DNA. Dietary antioxidants, folic acid, homocysteine, total antioxidant status (FRAP) and uric acid were measured in plasma. Food frequency questionnaires were administered. Vegetable consumption in summer/autumn was twice as high as in winter/spring. DNA damage did not vary consistently across the seasons. Mean plasma MDA levels for the MI and NL groups showed a clear pattern, with high levels in winter/spring and low levels in summer/autumn. Folic acid showed a reciprocal pattern, similar to the pattern of vegetable consumption. The RC group had the smallest seasonal variations in vegetable consumption, folic acid levels, and MDA. High winter MDA levels are seen in those individuals with relatively low folic acid; they never occur in subjects with high plasma folic acid, implying that folic acid might directly protect against lipid oxidation. This study illustrates the value of the molecular epidemiological approach, while emphasising the need for well characterised population groups and valid biomarkers. [Copyright &y& Elsevier]

Circulating advanced glycation end product levels in rats rapidly increase with acute renal failure. Background Advanced glycation end products (AGEs) are formed on proteins and peptides slowly during aging, and they accumulate in circulation and tissues in diabetes and chronic renal failure. Except for nonenzymatic glycation, enhanced oxidative/carbonyl stress is supposed to participate in their formation. The Kidney plays a key role in disposal of AGEs, particularly AGE-peptides. We assumed that even a short time combination of enhanced oxidative/carbonyl stress and a lack of renal function should result in elevation of circulating AGE levels. Method To verify this hypothesis, two models of acute renal failure in rats, bilateral nephrectomy and bilateral ureteral ligation, were employed, and the data were compared with those of sham-operated animals. Results AGE levels determined fluorimetrically or as carboxymethyllysine concentration rose by a factor of three within 48 hours. Enhanced levels of malondialdehyde and lipofuscin pointed to an enhanced oxidative/carbonyl stress. Activity of antioxidant enzymes such as superoxide dismutase and glutathione peroxidase were not compromised, or were even elevated, respectively. Total antioxidant status increased, probably as a consequence of an accumulation of indols and benzoic acid derivatives, uremic toxins with scavenging capacities, as shown for hippurate. Conclusions Evidence was given that circulating AGEs in the model of acute renal failure in rats undergo a substantial rise within a short time period. A source of increased AGEs is not clear, since except for the lack of the kidney function, accelerated synthesis of AGEs under enhanced oxidative/carbonyl stress as well as liberation of AGEs from tissues due to protein catabolism might be anticipated. If AGEs accumulate in acute renal failure in humans, their contributiion to acute toxicity, or of the development of the complications later, might be of importance. [ABSTRACT FROM AUTHOR]