6,976 research outputs found

    Potential Impact of the Resistance to Quaternary Ammonium Disinfectants on the Persistence of Listeria monocytogenes in Food Processing Environments

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    The persistence of certain strains of Listeria monocytogenes, even after the food processing environment has been cleaned and disinfected, suggests that this may be related to phenomena that reduce the concentration of the disinfectants to subinhibitory levels. This includes (i) the existence of environmental niches or reservoirs that are difficult for disinfectants to reach, (ii) microorganisms that form biofilms and create microenvironments in which adequate concentrations of disinfectants cannot be attained, and (iii) the acquisition of resistance mechanisms in L. monocytogenes, including those that lead to a reduction in the intracellular concentration of the disinfectants. The only available data with regard to the resistance of L. monocytogenes to disinfectants applied in food production environments refer to genotypic resistance to quaternary ammonium compounds (QACs). Although there are several well-characterized efflux pumps that confer resistance to QACs, it is a low-level resistance that does not generate resistance to QACs at the concentrations applied in the food industry. However, dilution in the environment and biodegradation result in QAC concentration gradients. As a result, the microorganisms are frequently exposed to subinhibitory concentrations of QACs. Therefore, the low-level resistance to QACs in L. monocytogenes may contribute to its environmental adaptation and persistence. In fact, in certain cases, the relationship between low-level resistance and the environmental persistence of L. monocytogenes in different food production chains has been previously established. The resistant strains would have survival advantages in these environments over sensitive strains, such as the ability to form biofilms in the presence of increased biocide concentrations.The authors were supported by grants RTA2011-00098-C02 and RTA2014-00045-C03 (Ministry of Economy and Competitiveness, Spain, Plan Nacional I+D+i co-financed by INIA and FEDER) during the preparation of this manuscript.S

    Whole-Genome Sequences of Seven Listeria monocytogenes Strains from Different Stages of a Poultry Meat Production Chain

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    Here, we present the draft genome sequences of seven Listeria monocytogenes strains isolated during three independent studies carried out in three stages of a poultry meat production chain. The genome sequences of these strains obtained from different stages can help to understand the possible transmission of L. monocytogenes.This work was supported in part by research project grant RTA2014-00045-C03 (INIA FEDER) from the Spanish Ministry of Science, Innovation and Universities. The support of the company Nutreco is also acknowledged. We thank the Unidad de Genómica (Instituto de Salud Carlos III, Majadahonda, Madrid, Spain) and Pilar López (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain) for technical assistance.S

    Boron in Very Metal-Poor Stars

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    We have observed the B I 2497 A line to derive the boron abundances of two very metal-poor stars selected to help in tracing the origin and evolution of this element in the early Galaxy: BD +23 3130 and HD 84937. The observations were conducted using the Goddard High Resolution Spectrograph on board the Hubble Space Telescope. A very detailed abundance analysis via spectral synthesis has been carried out for these two stars, as well as for two other metal-poor objects with published spectra, using both Kurucz and OSMARCS model photospheres, and taking into account consistently the NLTE effects on the line formation. We have also re-assessed all published boron abundances of old disk and halo unevolved stars. Our analysis shows that the combination of high effective temperature (Teff > 6000 K, for which boron is mainly ionized) and low metallicity ([Fe/H]<-1) makes it difficult to obtain accurate estimates of boron abundances from the B I 2497 A line. This is the case of HD 84937 and three other published objects (including two stars with [Fe/H] ~ -3), for which only upper limits can be established. BD +23 3130, with [Fe/H] ~ -2.9 and logN(B)_NLTE=0.05+/-0.30, appears then as the most metal-poor star for which a firm measurement of the boron abundance presently exists. The evolution of the boron abundance with metallicity that emerges from the seven remaining stars with Teff < 6000 K and [Fe/H]<-1, for which beryllium abundances were derived using the same stellar parameters, shows a linear increase with a slope ~ 1. Furthermore, the B/Be ratio found is constant at a value ~ 20 for stars in the range -3<[Fe/H]<-1. These results point to spallation reactions of ambient protons and alpha particles with energetic particles enriched in CNO as the origin of boron and beryllium in halo stars.Comment: 38 pages, 11 Encapsulated Postscript figures (included), uses aaspp4.sty. Accepted for publication in The Astrophysical Journal. The preprint is also available at: http://www.iac.es/publicaciones/preprints.htm

    Validity of a Clinical Scale in Predicting the Failure of Non-Invasive Ventilation in Hypoxemic Patients

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    Introduction: The HACOR scale is a clinical score that can predict early failure of NIV in hypoxemic acute respiratory failure (ARF) The aim of this study is to analyze the validity of the HACOR scale. Methods: A retrospective study of a cohort of over 2749 episodes on 2711 consecutive patients requiring NIV for hypoxemic ARF in a polyvalent intensive care unit. The scale was measured before starting NIV and at 1, 6, 12, 24 and 48 h after the initiation of NIV. Results: NIV failure occurred in 963 patients (35%). The value of the HACOR scale before NIV did not differ between success and failure. However, at 1, 6, 12, 24 and 48 h of NIV, the scale values clearly differed between the two groups. The HACOR scale at NIV initiation accurately predicts NIV failure in the first hour, with an optimal cut-off value of 8 points. The AUC for predicting NIV failure with HACOR at 1 h is greater than 0.9 in patients with pneumonia and adult respiratory distress syndrome (ARDS). Conclusions: The HACOR scale measured at 1 h after NIV initiation accurately predicts NIV failure, especially in pneumonia and ARDS.info:eu-repo/semantics/publishedVersio

    Oxygen abundances in unevolved metal-poor stars from near-UV OH lines

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    We have performed a detailed oxygen abundance analysis of 23 metal-poor (-3.0<[Fe/H]<-0.3) unevolved halo stars and one giant through the OH bands in the near UV, using high-resolution echelle spectra. Oxygen is found to be overabundant with respect to iron in these stars, with the [O/Fe] ratio increasing from 0.6 to 1 between [Fe/H]=-1.5 and -3.0. The behavior of the oxygen overabundance with respect to [Fe/H] is similar to that seen in previous works based on OI IR triplet data (Abia and Rebolo 1989; Tomkin et al. 1992; Cavallo, Pilachowski, and Rebolo 1997). Contrary to the previously accepted picture, our oxygen abundances, derived from low-excitation OH lines, agree well with those derived from high-excitation lines of the triplet. For nine stars in common with Tomkin et al. we obtain a mean difference of 0.00+/-0.11 dex with respect to the abundances determined from the triplet using the same stellar parameters and model photospheres. For four stars in our sample we have found measurements of the [OI] 6300 A line in the literature, from which we derive oxygen abundances consistent (average difference 0.09 dex) with those based on OH lines, showing that the long standing controversy between oxygen abundances from forbidden and permitted lines in metal-poor unevolved stars can be resolved. Our new oxygen abundances show a smooth extension of the Edvardsson et al.'s (1993) [O/Fe] versus metallicity curve to much lower abundances, with a slope -0.31+/- 0.11 (taking into account the error bars in both oxygen abundances and metallicities) in the range -3<[Fe/H]<-1.Comment: 17 pages, 8 figures, 3 table

    Plasticity and dystonia: a hypothesis shrouded in variability.

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    Studying plasticity mechanisms with Professor John Rothwell was a shared highlight of our careers. In this article, we discuss non-invasive brain stimulation techniques which aim to induce and quantify plasticity, the mechanisms and nature of their inherent variability and use such observations to review the idea that excessive and abnormal plasticity is a pathophysiological substrate of dystonia. We have tried to define the tone of our review by a couple of Professor John Rothwell's many inspiring characteristics; his endless curiosity to refine knowledge and disease models by scientific exploration and his wise yet humble readiness to revise scientific doctrines when the evidence is supportive. We conclude that high variability of response to non-invasive brain stimulation plasticity protocols significantly clouds the interpretation of historical findings in dystonia research. There is an opportunity to wipe the slate clean of assumptions and armed with an informative literature in health, re-evaluate whether excessive plasticity has a causal role in the pathophysiology of dystonia

    Prevalence and Population Diversity of Listeria monocytogenes Isolated from Dairy Cattle Farms in the Cantabria Region of Spain

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    Listeria monocytogenes is an opportunistic pathogen that is widely distributed in the environment. Here we show the prevalence and transmission of L. monocytogenes in dairy farms in the Cantabria region, on the northern coast of Spain. A total of 424 samples was collected from 14 dairy farms (5 organic and 9 conventional) and 211 L. monocytogenes isolates were recovered following conventional microbiological methods. There were no statistically significant differences in antimicrobial resistance ratios between organic and conventional farms. A clonal relationship among the isolates was assessed by pulsed field gel electrophoresis (PFGE) analysis and 64 different pulsotypes were obtained. Most isolates (89%, n = 187) were classified as PCR serogroup IVb by using a multiplex PCR assay. In this case, 45 isolates of PCR serogroup IVb were whole genome-sequenced to perform a further analysis at genomic level. In silico MLST analysis showed the presence of 12 sequence types (ST), of which ST1, ST54 and ST666 were the most common. Our data indicate that the environment of cattle farms retains a high incidence of L. monocytogenes, including subtypes involved in human listeriosis reports and outbreaks. This pathogen is shed in the feces and could easily colonize dairy products, as a result of fecal contamination. Effective herd and manure management are needed in order to prevent possible outbreaks.This work was supported by Research Project grants RTA08-099, RTA2008-00080-C02, RTA2014-00045-C03-01 (INIA and FEDER) from the Spanish Ministry of Economy and Competitiveness and RTI2018-098267-R-C31 (INIA and FEDER) from the Spanish Ministry of Science and Innovation.S

    Safety of the feed additive consisting of manganese chelates of lysine and glutamic acid for all animal species (Zinpro Animal Nutrition)

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    Following a request from the European Commission, the Panel&nbsp;on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety for target animals of manganese chelates of lysine and glutamic acid (Manganese-LG) as a nutritional feed additive for all animal species. The European Commission request followed an opinion of the FEEDAP Panel&nbsp;published in 2020; in that opinion, the FEEDAP Panel&nbsp;could conclude on the safety of the additive for chickens for fattening, but not for the rest of the target animals. The applicant submitted additional information to allow the FEEDAP Panel&nbsp;to complete its assessment; these additional data, comprising two tolerance studies (one with chickens for fattening and one with laying hens), were the subject of this opinion. The tolerance study in laying hens was not considered for the assessment since the housing conditions of the animals were not appropriate according to the relevant EU provisions. The results of the tolerance study in chickens for fattening showed that Manganese-LG at the highest level tested – 800 mg Mn/kg feed – is safe for these target animals. The FEEDAP Panel&nbsp;also considered a previous tolerance study in chickens for fattening. Taking all the evidence together the Panel&nbsp;concluded that Manganese-LG is safe for chickens for fattening at 150 mg Mn/kg feed, with a margin of safety of 5.5. This conclusion can be extrapolated to all animal species and categories provided that the maximum authorised levels in the EU for total manganese in feed are not exceeded

    Safety and efficacy of copper chelates of lysine and glutamic acid as a feed additive for all animal species

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    Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of copper chelates of lysine and glutamic acid (Copper-LG) as a nutritional feed additive for all animal species. The EFSA Panel&nbsp;on Additives and Products or Substances used in Animal Feed (FEEDAP) concludes that, owing to safety considerations, Copper-LG should not be used in water for drinking. Copper-LG is safe for chickens for fattening; this conclusion can be extrapolated to all animal species and categories provided that the maximum authorised levels in the EU for total copper in feed are not exceeded. No increases in the copper content of animal tissues/products are expected from the use of Copper-LG in animal nutrition. There is no indication that the toxicity of Copper-LG is essentially different from that of inorganic divalent copper. The use of Copper-LG in animal nutrition is of no concern for consumer safety provided that the maximum authorised total copper in feed is respected. Owing to the copper and nickel content of Copper-LG, the handling of the additive, poses a risk to users by inhalation. The additive is considered as a skin and respiratory sensitiser; it is corrosive to the eye while it is non-irritant to skin. The additive is intended to be a substitute for other authorised copper additives and will not further increase the environmental burden of copper; therefore, the FEEDAP Panel&nbsp;considers that the use of the additive in animal nutrition would not pose an additional risk for the environment. Copper-LG is a bioavailable source of copper, comparable to the standard inorganic copper source, and therefore, the additive is efficacious in meeting the birds copper requirements; this conclusion can be extrapolated to all animal species/categories. The FEEDAP Panel&nbsp;posed a recommendation concerning the description of the additive

    Declínio de empatia e formação de estudantes de enfermagem

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    Indexación: Scopus.Objective: The objective of this article is to examine whether the levels of empathy fit the concept of empathic decline. Method: This was a non-experimental and cross-sectional study. Two populations of nursing students in two nursing programs were studied: Universidad San Sebastián (Santiago, Chile) and Universidad Mayor (Temuco, Chile). The original data on empathy, assessed by the Jeferson Scale of Empathy, were combined into a single data base. They were then analyzed by means of normality tests and homoscedasticity, Cronbach’s alpha, analysis of variance; the standard deviation of the dependent outcome measure (Sy.x) and the coefficient of determination (R2) were estimated. Results: The sample sizes from the two programs were 479 and 277, respectively. It was found that the distributions of the averages over the course of study for empathy (and its components) were constant, and in some cases increased. Conclusion: It was found that the distribution of the means of empathy in the nursing students analyzed did not conform to the classical empathic decline observed in other studies. Therefore, it is inferred that the traditional factors identified as causes of empathic erosion were not operating in the same way in the studied context.https://www.scielo.br/j/reeusp/a/YPfy3YRCCXwv7z8VPNZXjns/?lang=e
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