184 research outputs found

    Oxidation of aldehydes used as food additives by peroxynitrite

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    Benzaldehyde and its derivatives are used as food supplements. These substances can be used mainly as flavorings or as antioxidants. Besides, peroxynitrite, an oxidizing agent, could be formed in canned food. Both species could react between them. The present article has focused on the kinetic study of the oxidation of aldehydes by peroxynitrite. A reaction mechanism that justifies all the experimental results is proposed. This mechanism, in acidic media, passes through three competitive pathways: (a) a radical attack that produces benzoic acid. (b) peracid oxidation, and (c) a nucleophilic attack of peroxynitrous acid over aldehyde to form an intermediate, X, that produces benzoic acid, or, through a Cannizzaro-type reaction, benzoic acid and benzyl alcohol. All rate constants involved in the third pathway (c) have been calculated. These results have never been described in the literature in acid media. A pH effect was analyzed

    IFE Plant Technology Overview and contribution to HiPER proposal

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    HiPER is the European Project for Laser Fusion that has been able to join 26 institutions and signed under formal government agreement by 6 countries inside the ESFRI Program of the European Union (EU). The project is already extended by EU for two years more (until 2013) after its first preparatory phase from 2008. A large work has been developed in different areas to arrive to a design of repetitive operation of Laser Fusion Reactor, and decisions are envisioned in the next phase of Technology Development or Risk Reduction for Engineering or Power Plant facilities (or both). Chamber design has been very much completed for Engineering phase and starting of preliminary options for Reactor Power Plant have been established and review here

    The Relation of physical self-concept, anxiety, and BMI among mexicam university students

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    El propósito de la investigación es conocer y relacionar los resultados del autoconcepto físico, con diferentes tipos de ansiedad y el IMC en los estudiantes de enfermería y educación física dela península de Yucatán (México). La muestra estuvo formada por 264 participantes, de los cuales 91 eran varones y 173 mujeres, con edades comprendidas entre 18 y 25 años. Nuestros datos revelan que en el autoconcepto físico, los valores obtenidos por los estudiantes de educación física son superiores al de los estudiantes de enfermería. Los estudiantes de enfermería presentan mayores valores de ansiedad estado que los de educación física. La percepción que tienen los estudiantes de ciclos superiores en prácticamente todas las dimensiones del autoconcepto es superior a la del alumnado de ciclos inferiores. Los niveles de ansiedad disminuyen conforme pasan de ciclos inferiores a superioresThe purpose of this paper is to know and relate the results of the various dimensions formed by the physical self-concept with respect to the different types of anxiety and the BMI among nursing and physical education students in the area of the Yucatán peninsula in Mexico. The study is based on a sample of 264 people, being 91 men and 173 women between the ages of 18 and 25. The outcome shows that the values obtained by physical education students are higher than those obtained by nursing students regarding the physical selfconcept. Nursing students present a higher level of anxiety compared to physical education students. The perception showed by junior and senior students with regard to almost all dimensions of self-concept is higher than that of freshmen and sophomore students. Anxiety level among students decreases throughout the year

    Effects of nitrogen fertilization and nitrification inhibitor product on vegetative growth, production and oil quality in ‘Arbequina’ hedgerow and ‘Picual’ vase-trained orchards

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    Two experiments were carried out in olive orchards in the center of Spain over a three-year period. In this cold and dry area, growers traditionally apply large amounts of N with no experimental knowledge. An ‘Arbequina’ hedgerow and ‘Picual’ vase orchards were fertilized with two N-doses applied to the soil in spring with or without the nitrification inhibitor (DMPP). Vegetative growth, fruit and oil characteristics were evaluated. These variables were affected by the N-treatment during the 3rd year. The lowest N-application increased vegetative growth, while when N-leaf composition was higher than 2%, fruit dry weight, oil content and oil phenol content were reduced. ‘Picual’ did not respond to N-applications. The effect of DMPP on growth or production was not consistent and a lower phenolic content was obtained for ‘Arbequina’. Our results demonstrated that in this dry land, N-fertilization is not always necessary and oil quality can be negatively affected with high doses

    Provision of ecological infrastructures to increase pollinators and other beneficial organisms in rainfed crops in Central Spain

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    In sustainable intensive agriculture, the biodiversity of monoculture fields can be increased by managing the field margins to provide ecological infrastructures that serve as refuges and resources for beneficial organisms (pollinators and natural enemies). In the present work we summarize two years of field trials following the goal to increase biodiversity of beneficial fauna in a barley field in Central Spain by sowing different herbaceous mixtures in the field margins. The presence of arthropods visiting flowers on plots sown with different types of seed mixtures and unsown natural flora (control plot) was compared by visual sampling every week between April and June. The results showed that a combination of herbaceous big-size seeds was the most successful mixture emerging under our experimental conditions and achieved a higher number of visits of beneficial arthropods than the unsown natural vegetation

    Genetic screening reveals phospholipid metabolism as a key regulator of the biosynthesis of the redox-active lipid coenzyme Q.

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    Mitochondrial energy production and function rely on optimal concentrations of the essential redox-active lipid, coenzyme Q (CoQ). CoQ deficiency results in mitochondrial dysfunction associated with increased mitochondrial oxidative stress and a range of pathologies. What drives CoQ deficiency in many of these pathologies is unknown, just as there currently is no effective therapeutic strategy to overcome CoQ deficiency in humans. To date, large-scale studies aimed at systematically interrogating endogenous systems that control CoQ biosynthesis and their potential utility to treat disease have not been carried out. Therefore, we developed a quantitative high-throughput method to determine CoQ concentrations in yeast cells. Applying this method to the Yeast Deletion Collection as a genome-wide screen, 30 genes not known previously to regulate cellular concentrations of CoQ were discovered. In combination with untargeted lipidomics and metabolomics, phosphatidylethanolamine N-methyltransferase (PEMT) deficiency was confirmed as a positive regulator of CoQ synthesis, the first identified to date. Mechanistically, PEMT deficiency alters mitochondrial concentrations of one-carbon metabolites, characterized by an increase in the S-adenosylmethionine to S-adenosylhomocysteine (SAM-to-SAH) ratio that reflects mitochondrial methylation capacity, drives CoQ synthesis, and is associated with a decrease in mitochondrial oxidative stress. The newly described regulatory pathway appears evolutionary conserved, as ablation of PEMT using antisense oligonucleotides increases mitochondrial CoQ in mouse-derived adipocytes that translates to improved glucose utilization by these cells, and protection of mice from high-fat diet-induced insulin resistance. Our studies reveal a previously unrecognized relationship between two spatially distinct lipid pathways with potential implications for the treatment of CoQ deficiencies, mitochondrial oxidative stress/dysfunction, and associated diseases

    Factors Associated With Short-Term Eradication of Rectal Colonization by KPC-2 Producing Klebsiella pneumoniae in an Outbreak Setting

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    Background: KPC-producing Klebsiella pneumoniae (KPCKP) is a threat for patients admitted to healthcare institutions. Objectives: To assess the efficacy of several decolonization strategies for KPCKP rectal carriage. Methods: Observational study performed in a 750-bed university center from July to October 2018 on the efficacy of a 10-day non-absorbable oral antibiotic (NAA) regimen (colistin 10 mg/ml, amikacin 8 mg/ml, and nystatin 30 mg/ml, 10 ml/6 h) vs. the same regimen followed by a probiotic (Vivomixx®) for 20 days in adult patients with KPCKP rectal colonization acquired during an outbreak. Results: Seventy-three patients colonized by KPCKP were included, of which 21 (29%) did not receive any treatment and 52 (71.2%) received NAA either alone (n = 26, 35.6%) or followed by a probiotic (n = 26, 35.6%). Eradication was observed in 56 (76.7%) patients and the only variable significantly associated with it was not receiving systemic antibiotics after diagnosis of rectal carriage [22/24 (91.6%) vs. 34/49 (69.3%), p = 0.04]. Eradication in patients receiving NAA plus probiotic was numerically but not significantly higher than that of controls [23/26 (88.4%) vs. 15/21 (71.4%), p = 0.14] and of those receiving only NAA (OR = 3.4, 95% CI = 0.78-14.7, p = 0.09). Conclusion: In an outbreak setting, rectal carriage of KPCKP persisted after a mean of 36 days in about one quarter of patients. The only factor associated with eradication was not receiving systemic antibiotic after diagnosis. A 10-day course of NAA had no impact on eradication. Probiotics after NAA may increase the decolonization rate, hence deserving further study

    Recent Advancements in the LC- and GC-Based Analysis of Malondialdehyde (MDA): A Brief Overview

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    Malondialdehyde (MDA) is an end-product of lipid peroxidation and a side product of thromboxane A2 synthesis. Moreover, it is not only a frequently measured biomarker of oxidative stress, but its high reactivity and toxicity underline the fact that this molecule is more than “just” a biomarker. Additionally, MDA was proven to be a mutagenic substance. Having said this, it is evident that there is a major interest in the highly selective and sensitive analysis of this molecule in various matrices. In this review, we will provide a brief overview of the most recent developments and techniques for the liquid chromatography (LC) and gas chromatography (GC)-based analysis of MDA in different matrices. While the 2-thiobarbituric acid assay still is the most prominent methodology for determining MDA, several advanced techniques have evolved, including GC–MS(MS), LC–MS(MS) as well as several derivatization-based strategies

    A Novel Therapy for Melanoma Developed in Mice: Transformation of Melanoma into Dendritic Cells with Listeria monocytogenes

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    Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal
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