Oxidation of clofibric acid in aqueous solution using a non-thermal plasma discharge or gamma radiation

In this work, we study degradation of clofibric acid (CFA) in aqueous solution using either ionizing radiation from a $^{60}$Co source or a non-thermal plasma produced by discharges in the air above the solution. The results obtained with the two technologies are compared in terms of effectiveness of CFA degradation and its by-products. In both cases the CFA degradation follows a quasi-exponential decay in time well modelled by a kinetic scheme which considers the competition between CFA and all reaction intermediates for the reactive species generated in solution as well as the amount of the end product formed. A new degradation law is deduced to explain the results. Although the end-product CO$_2$ was detected and the CFA conversion found to be very high under the studied conditions, HPLC analysis reveals several degradation intermediates still bearing the aromatic ring with the chlorine substituent. The extent of mineralization is rather limited. The energy yield is found to be higher in the gamma radiation experiments.Comment: 25 pages, 7 figure

Use of statins and the risk of new onset Diabetes Mellitus

Indexación: Web of Science; ScieloSe ha descrito relación entre el uso de estatinas y aparición de nueva diabetes. Se revisa advertencia de la FDA, así como análisis de estudios y meta análisis, que permiten deducir una acción de las estatinas que favorece el desarrollo de nueva diabetes. Las precauciones del uso de estatinas se deben orientar a pacientes con factores de riesgo de diabetes en prevención primaria cardiovascular. Se expresa la necesidad de estudios prospectivos con objetivos primarios específicos, para mayor precisión de información y adopción de recomendaciones basadas en alto nivel de evidencias.Relationship between statin use and appearance of new diabetes has been described. We review the FDA warning and analysis of studies and meta-analysis, which point to an action of statins which favors the development of new diabetes. Precautions of statin use should guide patients with risk factors for diabetes in primary cardiovascular prevention. It expresses the need for prospective studies with specific primary objectives, for accuracy of information and making recommendations based on high-level evidence.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-85602012000300007&nrm=is

Root seasonal pattern, spatial distribution, and C:N ratio of matgrasspasture (Nardus stricta L.) in the Lombardy Prealps

The aim of the present study was to investigate carbon and nutrient cycling and the role of root dynamics in terrestrial ecosystems such as large abandoned pastures and natural grasslands present in the Prealps, for which below-ground processes are currently enigmatic. In particular, we quantified root/leaf biomass and C:N ratio throughout two growing seasons. Additionally, root traits such as root length density (RLD), root mass density (RMD), and root diameter classes (RDC) were also investigated with the aim of understanding the spatial distribution of roots in the soil. In our samples, we found that the roots could be divided into three main diameter classes and hence quantified the presence of each class along the soil profile. With regard to total root biomass, we found the occurrence of two peaks of biomass accumulation during the growth season, and when biomass accumulation was compared with climatic data, it was impossible to obtain a clear indication of the root turnover rate. In fact, the strong influence of grazing on the above-ground biomass could have affected, in turn, root biomass. In future, this possible complication will be avoided by repeating the measurements within enclosures to avoid grazing interference. We found that C:N ratio remained constant, with a single peak, suggesting a lower root decomposition during the warmest period (August 2006). The concentration of nitrogen in roots decreased with depth as a result of a decrease in roots with smaller diameters. The reverse was found for carbon content, which increased with depth, probably due to an increase in roots with larger diameters. This study represents the first attempt to estimate root turnover rates in this prealpine ecosystem, which have been analysed to date only for the above-ground biomass

A TGA/FT-IR study for OC and EC quantification applied to carbonaceous aerosol collected in Milan (Italy)

International audienceCarbon analysis consists in the evaluation of the carbonaceous content of the aerosol (TC) but, more importantly, of its distribution between the two components EC (Elemental Carbon) and OC (Organic Carbon) that are characterized by different physical-chemical properties. In spite of the numerous studies focused on this topic, nowadays, a universal methodology for the determination of the two components EC and OC is not available. In fact OC and EC (also known as black carbon or soot) are operationally defined by the method of analysis and, as a consequence, different methods can produce different results. In this paper we present results on the application of TGA/FT-IR (Thermogravimetric Analysis/Fourier Transformed Infrared Spectroscopy) to the characterization of carbonaceous aerosols. The analytical methodology was applied to PM10 four-hour time resolution samples collected in Milan urban area. The method is a two-steps thermal one and bases itself on the different thermal behaviour of OC and EC. It has been set up analyzing suitable standards containing both organic and elemental carbon. Carbon quantification is achieved by on-line, continuous monitoring of CO2 infrared absorption at 2361 cm?1. A good separation between OC and EC on particulate matter samples has been obtained. Ranges and average values were respectively 12?70 µg/m3 and 20 µg/m3 for OC and 0.2?6 µg/m3 and 2 µg/m3 for EC. On average OC and EC made up respectively 29.3 (±12.8) % and 2.5 (±1.8) % of PM10 fraction. The method reliability has been verified by comparison with TOT (Thermal Optical Transmission) technique. OC and EC values determined for ambient samples of PM10 were also correlated with meteorological parameters as well as with Radon concentrations

Genome-Wide Expression Analysis in Drosophila Reveals Genes Controlling Circadian Behavior

In Drosophila, a number of key processes such as emergence from the pupal case, locomotor activity, feeding, olfaction, and aspects of mating behavior are under circadian regulation. Although we have a basic understanding of how the molecular oscillations take place, a clear link between gene regulation and downstream biological processes is still missing. To identify clock-controlled output genes, we have used an oligonucleotide-based high-density array that interrogates gene expression changes on a whole genome level. We found genes regulating various physiological processes to be under circadian transcriptional regulation, ranging from protein stability and degradation, signal transduction, heme metabolism, detoxification, and immunity. By comparing rhythmically expressed genes in the fly head and body, we found that the clock has adapted its output functions to the needs of each particular tissue, implying that tissue-specific regulation is superimposed on clock control of gene expression. Finally, taking full advantage of the fly as a model system, we have identified and characterized a cycling potassium channel protein as a key step in linking the transcriptional feedback loop to rhythmic locomotor behavior.Fil: Ceriani, Maria Fernanda. The Scripps Research Institute; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Hogenesch, John B.. Genomics Institute of the Novartis Research Foundation; Estados UnidosFil: Yanovsky, Marcelo Javier. The Scripps Research Institute; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Panda, Satchidananda. Genomics Institute of the Novartis Research Foundation; Estados Unidos. The Scripps Research Institute; Estados UnidosFil: Straume, Martin. University Of Virginia; Estados UnidosFil: Kay, Steve A.. Genomics Institute of the Novartis Research Foundation; Estados Unidos. The Scripps Research Institute; Estados Unido

Plant Polyphenols and Exendin-4 Prevent Hyperactivity and TNF-alpha Release in LPS-Treated In vitro Neuron/Astrocyte/Microglial Networks

Increasing evidence supports a decisive role for neuroinflammation in the neurodegenerative process of several central nervous system (CNS) disorders. Microglia are essential mediators of neuroinflammation and can regulate a broad spectrum of cellular responses by releasing reactive oxygen intermediates, nitric oxide, proteases, excitatory amino acids, and cytokines. We have recently shown that also in ex-vivo cortical networks of neurons, astrocytes and microglia, an increased level of tumor necrosis factor-alpha (TNF-α) was detected a few hours after exposure to the bacterial endotoxin lipopolysaccharide (LPS). Simultaneously, an atypical “seizure-like” neuronal network activity was recorded by multi-electrode array (MEA) electrophysiology. These effects were prevented by minocycline, an established anti-inflammatory antibiotic. We show here that the same inhibitory effect against LPS-induced neuroinflammation is exerted also by natural plant compounds, polyphenols, such as curcumin (CU, curcuma longa), crocin (CR, saffron), and resveratrol (RE, grape), as well as by the glucagon like peptide-1 receptor (GLP-1R) agonist exendin-4 (EX-4). The drugs tested also caused per-se early transient (variable) changes of network activity. Since it has been reported that LPS-induced neuroinflammation causes rearrangements of glutamate transporters in astrocytes and microglia, we suggest that neural activity could be putatively increased by an imbalance of glial glutamate transporter activity, leading to prolonged synaptic glutamatergic dysregulation