1,925 research outputs found

    Prevalence and Distribution of High-Risk Genotypes of HPV in Women with Severe Cervical Lesions in Madrid, Spain: Importance of Detecting Genotype 16 and Other High-Risk Genotypes

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    Background. Persistent infection with high-risk human papillomavirus (HR-HPV) has been demonstrated to be the necessary causal factor for developing cervical cancer. To know the most prevalent HR-HPV in different geographical areas is important to design diagnostic tests and implementation of vaccines. Objectives. The goal of this study is to evaluate the prevalence of HR-HPV in a total of 1001 patients, 198 with normal cytology results, 498 with low-grade squamous intraepithelial lesion (LSIL), and 205 with high-grade squamous intraepithelial lesion (HSIL) who attended our gynaecology department for opportunistic screening of HPV infection. Study design. Cervical samples were taken in a PreservCyt vial (Cytyc Corporation, Boxborough, MA). Hybrid capture assay was carried out following the manufacturer's instructions (Digene Corp., Gaithersburg, MD). All samples were further studied with polymerase chain reaction (PCR) (Linear Array HPV Genotyping Test, Roche Diagnostics, Mannheim, Germany). Results. Genotype 16 was the most prevalent HR-HPV in the three groups, 17.8% in the patients with normal cytology results, 22.3% in the LSIL group, and 60% in the HSIL group. Genotype 18 had a very low prevalence in all groups. Other HR-HPV genotypes such as genotype 31, genotype 58 and genotype 52 were found in significant numbers in HSIL patients. Discussion. Our data show that genotypes 16, 31, 58, and 52 are the most prevalent HR-HPV in cervical samples with severe intraepithelial lesion in Spain. There may be some geographical variation in prevalence of carcinogenic types, and it must be considered for designing diagnostic tests and vaccine

    Prevalence and Distribution of High-Risk Genotypes of HPV in Women with Severe Cervical Lesions in Madrid, Spain: Importance of Detecting Genotype 16 and Other High-Risk Genotypes

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    Background. Persistent infection with high-risk human papillomavirus (HR-HPV) has been demonstrated to be the necessary causal factor for developing cervical cancer. To know the most prevalent HR-HPV in different geographical areas is important to design diagnostic tests and implementation of vaccines. Objectives. The goal of this study is to evaluate the prevalence of HR-HPV in a total of 1001 patients, 198 with normal cytology results, 498 with low-grade squamous intraepithelial lesion (LSIL), and 205 with high-grade squamous intraepithelial lesion (HSIL) who attended our gynaecology department for opportunistic screening of HPV infection. Study design. Cervical samples were taken in a PreservCyt vial (Cytyc Corporation, Boxborough, MA). Hybrid capture assay was carried out following the manufacturer's instructions (Digene Corp., Gaithersburg, MD). All samples were further studied with polymerase chain reaction (PCR) (Linear Array HPV Genotyping Test, Roche Diagnostics, Mannheim, Germany). Results. Genotype 16 was the most prevalent HR-HPV in the three groups, 17.8% in the patients with normal cytology results, 22.3% in the LSIL group, and 60% in the HSIL group. Genotype 18 had a very low prevalence in all groups. Other HR-HPV genotypes such as genotype 31, genotype 58 and genotype 52 were found in significant numbers in HSIL patients. Discussion. Our data show that genotypes 16, 31, 58, and 52 are the most prevalent HR-HPV in cervical samples with severe intraepithelial lesion in Spain. There may be some geographical variation in prevalence of carcinogenic types, and it must be considered for designing diagnostic tests and vaccine

    Effect of adding Salix babylonica Extracts and Exogenous Enzymes to Basal Diets on the Meat Quality of Growing Suffolk Lambs

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    It was evaluated the effect of adding Salix babylonica L. extracts and exogenous enzymes in combination or individually on meat quality in growing Suffolk lambs. Animals were divided into 4 groups of 4 animals each in a completely randomized design (CRD). Treatments were: (i) Control: basal diet of concentrate (30%) mixture and corn silage roughage (70%); (ii) EZE (exogenous enzymes): basal diet plus 10 g of enzyme (Zado®); (iii) SB (Salix babylonica): basal diet plus 30 ml of S babylonica extracts, and (iv) EZESB (exogenous enzymes + Salix babylonica): basal diet plus 10 g enzyme and 30 ml of S. Babylonica extracts. Lambs were housed in individual cages for 60 days. Extracts were dosed orally while EZE was mixed with concentrate. At the end of the trial, lambs were slaughtered and Longissimus dorsi samples were analysed. Samples were analysed for CP, CF, ash and DM. Meat quality parameters included color, pH, carcass temperature and kidney fat. No significant differences for live weight, chemical composition, as well as hot carcass weight and cold, initial and final temperature and kideny fat. Meat lightness (variable L *) and pHf were improved (P<0.05) with EZESB treatment compared to the other three treatments, and the most optimal pHf four treatments being the most acidic. Lambs fed SB or EZE were not different from the control. In conclusion, a combined administration of EZESB to the basal diet improves meat quality by reducing the pH and increasing its lightness when compared to either EZE or SB, individually

    Metalloproteinase-dependent TLR2 ectodomain shedding is involved in soluble toll-like receptor 2 (sTLR2) production

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    Toll-like receptor (TLR) 2, a type I membrane receptor that plays a key role in innate immunity, recognizes conserved molecules in pathogens, and triggering an inflammatory response. It has been associated with inflammatory and autoimmune diseases. Soluble TLR2 (sTLR2) variants have been identified in human body fluids, and the TLR2 ectodomain can negatively regulate TLR2 activation by behaving as a decoy receptor. sTLR2 generation does not involve alternative splicing mechanisms, indicating that this process might involve a post-translational modification of the full-length receptor; however, the specific mechanism has not been studied. Using CD14+ peripheral human monocytes and the THP-1 monocytic leukemia-derived cell line, we confirm that sTLR2 generation increases upon treatment with pro-inflammatory agents and requires a post-translational mechanism. We also find that the constitutive and ligand-induced release of sTLR2 is sensitive to pharmacological metalloproteinase activator and inhibitors leading us to conclude that metalloproteinase TLR2 shedding contributes to soluble receptor production. By expressing human TLR2 in ADAM10- or ADAM17-deficient MEF cells, we find both enzymes to be implicated in TLR2 ectodomain shedding. Moreover, using a deletion mutant of the TLR2 juxtamembrane region, we demonstrate that this domain is required for sTLR2 generation. Functional analysis suggests that sTLR2 generated by metalloproteinase activation inhibitsTLR2-induced cytokine production by this monocytic leukemia-derived cell line. The identification of the mechanisms involved in regulating the availability of soluble TLR2 ectodomain and cell surface receptors may contribute further research on TLR2-mediated processes in innate immunity and inflammatory disorders

    Atmospheric sink of styrene, α-methylstyrene, trans-β-methylstyrene and indene: Rate constants and mechanisms of the Cl atoms initiated degradation

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    The kinetics and products of the oxidation of four aromatic compounds, i.e. styrene, α-methylstyrene, trans-β-methylstyrene and indene, with Cl atoms were determined at atmospheric pressure and room temperature. Kinetic experiments were carried out in a 400 L Teflon reaction chamber using GC-FID for the analysis of reactants and products were determined using a 56 L quartz-glass reactor coupled to FTIR spectrophotometer. The rate constants at 298 K, using different reference compounds, were (in units of cm3 molecule−1 s−1): kstyrene = (1.29 ± 0.52)×10−10, kα-methylstyrene = (1.55 ± 0.27)×10−10, ktrans-β-methylstyrene = (1.09 ± 0.23)×10−10 and kindene = (1.01 ± 0.30)×10−10. Observations with FTIR suggest that the main reaction is the addition of the Cl to the aliphatic chain of the aromatic molecules. We found benzaldehyde, benzoyl chloride, formaldehyde and formyl chloride from styrene; acetophenone, formaldehyde and formyl chloride from α-methylstyrene; and benzaldehyde, formaldehyde and acetyl chloride from trans-β-methylstyrene as the main oxidation products. DFT theoretical calculations were performed in order to shed light on the identification of the reaction products. To the best of our knowledge, this work represents the first determination of the rate coefficients and products for the reaction of the Cl atoms with these compounds, except for the rate constant of styrene which has been studied previously. The loss processes of the title compounds in the atmosphere are mostly controlled by reactions with OH radicals during the day and with NO3 at night, but in coastal areas and some polluted environments, Cl reactions became comparable with OH and NO3 radicals, with lifetimes of 2.2 h for styrene, 1.8 h for AMS, 2.5 h for TBMS and 2.8 h for indene

    Secondary organic aerosol formation from styrene photolysis and photooxidation with hydroxyl radicals

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    The formation of secondary organic aerosol (SOA) generated by irradiating styrene in the presence and/or absence of OH, NOx, H2O vapour and seed aerosol has been investigated for the first time. Experiments were conducted in a smog chamber at 298 K and atmospheric pressure. Styrene decay was measured by gas chromatography with a mass spectrometric detector (GC-MS), and the temporal evolution of the aerosol was monitored using a fast mobility particle sizer (FMPS). The SOA yield increases as the initial styrene concentration increases, leading to yields ranging from 1.8% to 3.5% for styrene photolysis, and from 2.4% to 5.0% for its photooxidation. In both cases, the organic aerosol formation can be expressed by a one-product gas/particle partitioning absorption model. The particle number concentration, mass and yield decrease in the presence of NOx and seed aerosol but increase at higher relative humidity (RH). The gas phase and SOA composition were analysed offline using a filter/denuder sampling system simultaneously collecting gas- and particle-phase products. Benzaldehyde was confirmed as the main gas-phase product of the reaction. However, although products in the particle phase were detected, they could not be identified. Moreover, the aqueous filter extracts were analysed using UV–Visible spectrophotometry to determine differences in the optical properties of SOA produced in the presence and absence of NOx. The results from this work may be used to discuss the implications of atmospheric SOA generation from styrene degradation

    Secondary organic aerosol formation from α-methylstyrene atmospheric degradation: Role of NOx level, relative humidity and inorganic seed aerosol

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    Secondary Organic Aerosol (SOA) formation during the photolysis and OH-photooxidation of α-methylstyrene was investigated using a simulation chamber at atmospheric pressure and room temperature (296 ± 1) K. α-Methylstyrene concentration was followed by gas chromatography with a mass spectrometric detector (GC–MS) and the aerosol production was monitored using a Fast Mobility Particle Sizer (FMPS). The effect of varying α-methylstyrene (0.5 ppm - 2 ppm) and NOx (0.5 ppm - 1.0 ppm) concentrations on SOA formation was explored, as was the effect of the relative humidity (RH) (5–50%) and the presence of inorganic seed particles. Results indicate that SOA yields increase at higher α-methylstyrene concentrations; low NOx and high RH conditions favour more rapid aerosol formation and a higher aerosol yield; SOA formation is independent of seed surface area, within the studied range, for both inorganic seed particles ((NH4)2SO4 and CaCl2). An off-line chemical analysis using a filter/denuder sampling system and GC–MS confirms acetophenone as the main gas phase product in both processes, photolysis and photooxidation. For the first time, SOA composition in α-methylstyrene degradation was analysed, observing acetophenone and acetol as products present in the formed aerosol in presence and absence of NOx

    Formation of secondary aerosols from the ozonolysis of styrene: effect of SO2 and H2O.

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    In this work we report the study of the ozonolysis of styrene and the reaction conditions leading to the formation of secondary aerosols. The reactions have been carried out in a Teflon chamber filled with synthetic air mixtures at atmospheric pressure and room temperature. We have found that the ozonolysis of styrene in the presence of low concentrations of SO2 readily produces new particles under concentrations of reactants lower than those required in experiments in the absence of SO2. Thus, nucleation events occur at concentrations around (5.6 ± 1.7) × 108molecule cm−3 (errors are 2σ±20%) and SO2 is consumed during the experiments. The reaction of the Criegee intermediates with SO2 to produce SO3 and then H2SO4 may explain (together with OH reactions’ contribution) the high capacity of styrene to produce particulate matter in polluted atmospheres. The formation of secondary aerosols in the smog chamber is inhibited under high H2O concentrations. So, the potential formation of secondary aerosols under atmospheric conditions depends on the concentration of SO2 and relative humidity, with a water to SO2 rate constants ratio kH2O/kSO2 = (2.8 ± 0.7) × 10−5 (errors are 2σ±20%)

    Hollow Gold Nanoparticles Produced by Femtosecond Laser Irradiation

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    [EN] Metallic hollow nanoparticles exhibit interesting optical properties that can be controlled by geometrical parameters. Irradiation with femtosecond laser pulses has emerged recently as a valuable tool for reshaping and size modification of plasmonic metal nanoparticles, thereby enabling the synthesis of nanostructures with unique morphologies. In this Letter, we use classical molecular dynamics simulations to investigate the solid-to-hollow conversion of gold nanoparticles upon femtosecond laser irradiation. Here, we suggest an efficient method for producing hollow nanoparticles under certain specific conditions, namely that the particles should be heated to a maximum temperature between 2500 and 3500 K, followed by a fast quenching to room temperature, with cooling rates lower than 120 ps. Therefore, we describe the experimental conditions for efficiently producing hollow nanoparticles, opening a broad range of possibilities for applications in key areas, such as energy storage and catalysis.This work has been funded by the Spanish Ministry of Science, Innovation and Universities (MICIU) (Grants RTI2018-095844-B-I00, PGC2018-096444-B-I00, and MAT2017-86659-R), the EUROfusion Consortium through Project ENR-IFE19.CCFE-01, and the Madrid Regional Government (Grants P2018/NMT-4389 and P2018/EMT-4437). A.P. is thankful for the support of FONDECYT under Grants 3190123 and 11180557, as well as from Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia FB-0807. K.L. acknowledges the support of the Russian Science Foundation (Project 19-19-00683). The authors acknowledge the computer resources and technical assistance provided by the Centro de Supercomputacion y Visualizacion de Madrid (CeSViMa) and the supercomputing infrastructure of the NLHPC (ECM-02). This Letter is based upon work from COST Action TUMIEE (CA17126)Castro-Palacio, JC.; Ladutenko, K.; Prada, A.; Gonzalez-Rubio, G.; Diaz-Nunez, P.; Guerrero-Martinez, A.; Fernández De Córdoba, P.... (2020). Hollow Gold Nanoparticles Produced by Femtosecond Laser Irradiation. The Journal of Physical Chemistry Letters. 11(13):5108-5114. https://doi.org/10.1021/acs.jpclett.0c01233S51085114111

    Composição de carboidratos do abacaxi (cv. pérola) e resposta glicêmica em humanos

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    Brazil is the third largest producer of pineapple (Ananas comosus) and the market for fresh pineapple is sustained by the Hawaii and Perola cultivars. In this work the Perola cultivar was divided into three main parts, shell, core and pulp, for characterization. Moisture in the pulp was higher (between 10 and 15%) than in the shell and core. The amount of protein was higher in the core (35%) than in the pulp and shell. Perola contained relatively low concentrations of total ascorbic acid in the edible parts, although higher levels of ascorbic acid in the shell. Citric acid corresponded to almost 60% of the total organic acids. The total soluble sugars [~7-12% (FW)] were predominantly sucrose, fructose and glucose. The core had almost twice as much total sugar (12%) than the pulp (6.8%). The amount of insoluble dietary fiber was around 1%, and the soluble fiber was less than 0.1%. The pulp showed the highest concentration of polyphenols (0.49%) and antioxidant activity (33 µmol.g-1) out of the parts. The consumption of the pineapple pulp or core produced a high glycemic index (~93%), but considering the glycemic load, this fruit can be considered as low dietary.O Brasil é o terceiro maior produtor de abacaxi(Ananas comosus) e as principais cultivares encontradas no mercado são Havaí e Pérola. Neste trabalho, frutas da cultivar Pérola foram divididas em casca, cerne e polpa e analisadas. A umidade da polpa foi superior (entre 10 e 15%) à encontrada na casca e no cerne. A concentração de proteína foi maior no cerne (35%) que na polpa e na casca. Essa cultivar contém baixas concentrações de ácido ascórbico nas partes comestíveis, no entanto a casca apresentou maiores níveis. O ácido cítrico correspondeu a aproximadamente 60% do total de ácidos orgânicos. Entre os açúcares solúveis [~7-12% (BU)], a sacarose, frutose e glicose foram predominantes. O cerne continha quase o dobro dos açúcares totais (12%) em relação à polpa (6,8%). A concentração de fibra alimentar insolúvel foi em torno de 1%, enquanto a de fibra solúvel foi menor que 0,1%. A polpa apresentou maior concentração de polifenóis (0,49%) e maior atividade antioxidante (33 µmol.g-1) que as demais partes. O consumo da polpa e do cerne produziu alto índice glicêmico (~93%), mas considerando a quantidade usual consumida, o abacaxi apresenta baixa carga glicêmica
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