18 research outputs found

    Oxidative stress in wild boars naturally and experimentally infected with mycobacterium bovis

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    This is an open access article distributed under the terms of the Creative Commons Attribution License.-- et al.Reactive oxygen and nitrogen species (ROS-RNS) are important defence substances involved in the immune response against pathogens. An excessive increase in ROS-RNS, however, can damage the organism causing oxidative stress (OS). The organism is able to neutralise OS by the production of antioxidant enzymes (AE); hence, tissue damage is the result of an imbalance between oxidant and antioxidant status. Though some work has been carried out in humans, there is a lack of information about the oxidant/antioxidant status in the presence of tuberculosis (TB) in wild reservoirs. In the Mediterranean Basin, wild boar (Sus scrofa) is the main reservoir of TB. Wild boar showing severe TB have an increased risk to Mycobacterium spp. shedding, leading to pathogen spreading and persistence. If OS is greater in these individuals, oxidant/antioxidant balance in TB-affected boars could be used as a biomarker of disease severity. The present work had a two-fold objective: i) to study the effects of bovine TB on different OS biomarkers (namely superoxide dismutase (SOD), catalasa (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS)) in wild boar experimentally challenged with Mycobacterium bovis, and ii) to explore the role of body weight, sex, population and season in explaining the observed variability of OS indicators in two populations of free-ranging wild boar where TB is common. For the first objective, a partial least squares regression (PLSR) approach was used whereas, recursive partitioning with regression tree models (RTM) were applied for the second. A negative relationship between antioxidant enzymes and bovine TB (the more severe lesions, the lower the concentration of antioxidant biomarkers) was observed in experimentally infected animals. The final PLSR model retained the GPX, SOD and GR biomarkers and showed that 17.6% of the observed variability of antioxidant capacity was significantly correlated with the PLSR X's component represented by both disease status and the age of boars. In the samples from free-ranging wild boar, however, the environmental factors were more relevant to the observed variability of the OS biomarkers than the TB itself. For each OS biomarker, each RTM was defined as a maximum by one node due to the population effect. Along the same lines, the ad hoc tree regression on boars from the population with a higher prevalence of severe TB confirmed that disease status was not the main factor explaining the observed variability in OS biomarkers. It was concluded that oxidative damage caused by TB is significant, but can only be detected in the absence of environmental variation in wild boar.This work was funded by the PAIDI Research Group RNM18 from Junta de Andalucía. ES was supported by the postdoctoral program (SFRH/BPD/96637/2013) of the Fundação para a Ciência ea Tecnologia, Portugal. We would like to thank the University of Aveiro (Department of Biology) and FCT/MEC for the financial support to CESAM RU (UID/AMB/50017) through national funds and, where applicable, co-financed by the FEDER, within the PT2020 Partnership Agreement.Peer reviewe

    Description of small and large-scale cross laminated timber fire tests

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    A large-scale fire test was conducted on a compartment constructed from cross laminated timber (CLT). The internal faces of the compartment were lined with non-combustible board, with the exception of one wall and the ceiling where the CLT was exposed directly to the fire inside the compartment. Extinction of the fire occurred without intervention. During the fire test, measurements were made of incident radiant heat flux, gas phase temperature, and in-depth temperature in the CLT. In addition, gas flow velocities and gas phase temperatures at the opening were measured, as well as incident heat fluxes at the facade due to flames and the plume leaving the opening. The fuel load was chosen to be sufficient to attain flashover, to achieve steady-state burning conditions of the exposed CLT, but to minimize the probability of uncertain behaviors induced by the specific characteristics of the CLT. Ventilation conditions were chosen to approximate maximum temperatures within a compartment. Wood cribs were used as fuel and, following decay of the cribs, self-extinction of the exposed CLT rapidly occurred. In parallel with the large-scale test, a small scale study focusing on CLT self-extinction was conducted. This study was used to establish: the range of incident heat fluxes for which self-extinction of the CLT can occur; the duration of exposure after which steady-state burning occurred; and the duration of exposure at which debonding of the CLT could occur. The large-scale test is described, and the results from both the small and large-scale tests are compared. It is found that self-extinction occurred in the large-scale compartment within the range of critical heat fluxes obtained from the small scale tests

    Oxidative Stress in Wild Boars Naturally and Experimentally Infected with Mycobacterium bovis

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    Reactive oxygen and nitrogen species (ROS-RNS) are important defence substances involved in the immune response against pathogens. An excessive increase in ROS-RNS, however, can damage the organism causing oxidative stress (OS). The organism is able to neutralise OS by the production of antioxidant enzymes (AE); hence, tissue damage is the result of an imbalance between oxidant and antioxidant status. Though some work has been carried out in humans, there is a lack of information about the oxidant/antioxidant status in the presence of tuberculosis (TB) in wild reservoirs. In the Mediterranean Basin, wild boar (Sus scrofa) is the main reservoir of TB. Wild boar showing severe TB have an increased risk to Mycobacterium spp. shedding, leading to pathogen spreading and persistence. If OS is greater in these individuals, oxidant/antioxidant balance in TB-affected boars could be used as a biomarker of disease severity. The present work had a two-fold objective: i) to study the effects of bovine TB on different OS biomarkers (namely superoxide dismutase (SOD), catalasa (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS)) in wild boar experimentally challenged with Mycobacterium bovis, and ii) to explore the role of body weight, sex, population and season in explaining the observed variability of OS indicators in two populations of free-ranging wild boar where TB is common. For the first objective, a partial least squares regression (PLSR) approach was used whereas, recursive partitioning with regression tree models (RTM) were applied for the second. A negative relationship between antioxidant enzymes and bovine TB (the more severe lesions, the lower the concentration of antioxidant biomarkers) was observed in experimentally infected animals. The final PLSR model retained the GPX, SOD and GR biomarkers and showed that 17.6% of the observed variability of antioxidant capacity was significantly correlated with the PLSR X's component represented by both disease status and the age of boars. In the samples from free-ranging wild boar, however, the environmental factors were more relevant to the observed variability of the OS biomarkers than the TB itself. For each OS biomarker, each RTM was defined as a maximum by one node due to the population effect. Along the same lines, the ad hoc tree regression on boars from the population with a higher prevalence of severe TB confirmed that disease status was not the main factor explaining the observed variability in OS biomarkers. It was concluded that oxidative damage caused by TB is significant, but can only be detected in the absence of environmental variation in wild boar

    Evaluacion rapida del uso de trampas de feromonas para la captura de IPS calligraphus y sus enemigos naturales en San Fernando (Nueva Segovia)

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    El presente estudio fue realizado para evaluar la efectividad de una feromona sexual para monitorear las poblaciones de gorgojos descortezadores; particularmente del gorgojo descortezador secundario Ips calligraphus, la fluctuación poblacional de dicho gorgojo y la de dos depredadores de éstos, Tecnochila sp y Enuclerus sp. En el contexto del estudio un total de cinco trampas tipo “Lindaren non sticky trap” fueron ubicadas en 3 lugares forestales: Las Tapias, San José y La Unión, en el Municipio de San Fernando, Nueva Segovia; pero solamente dos trampas fueron directamente evaluadas bajo la responsabilidad de la autora del presente estudio. Una trampa fue cebada con feromona sexual de Ips calligraphus , y la otra no. El estudio fue realizado durante el período de Diciembre 2006 a Marzo 2007. En los tres sitios estudiados la feromona sexual fue altamente específica (P<0.001) para atraer Ips calligraphus, la fluctuación poblacional del insecto no difirió en los tres sitios estudiados, sin embargo el mayor número de Ips calligraphus fue capturado en las tapias. El objetivo de observar la fluctuación poblacional de depredadores Tecnochila sp. o Enoclerus sp. no fue llevado a cabo debido a que no cayó ninguno en las trampas de estudio

    Revision of the distribution of cabreras vole (Microtus cabrerae Thomas 1906) in Andalusia (Southern Spain).

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    This paper consists of a revision of existing records of Cabrera¿s Vole Microtus cabrerae in Andalusia (southern Spain) and provides new data from a survey of both previously investigated and new areas. Cabrera¿s voles were found at only three of the 17 previously known localities, whilst the species may in fact be extinct in 12 localities. Our results suggest that the species could have disappeared from the central part of the province of Granada. Nevertheless, fieldwork revealed 138 new localities in 24 UTM 10x10 km squares scattered throughout the Cazorla-Segura Mountains and the extreme north of the provinces of Almería and Granada. In 13 of these squares, the presence of the species was confirmed by the capture of 16 specimens. Despite the new localities discovered, the species should still be considered as `Critically Endangered¿ in Andalusia.Peer Reviewe

    Nuevas citas para el topillo nival (Chionomys nivalis) en Sierra Nevada

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    A revision of the distribution of Cabrera’s vole (&lt;em&gt;Microtus cabrerae&lt;/em&gt; Thomas 1906) in Andalusia (southern Spain)

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    &lt;strong&gt;Abstract&lt;/strong&gt;&#13; This paper consists of a revision of existing records of Cabrera’s Vole &lt;em&gt;Microtus cabrerae&lt;/em&gt; in Andalusia (south of Spain) and provides new data from a survey of both previously investigated and new areas. Cabrera’s voles were found at only three of the 17 previously known localities, whilst the species may be in fact extinct in 12 localities. Our results suggest that the species could have disappeared from the central part of the province of Granada. Nevertheless, fieldwork revealed 138 new localities in 24 UTM 10x10 km squares scattered throughout the Cazorla-Segura Mountains and the extreme north of the provinces of Almería and Granada. In 13 of these squares, the presence of the species was confirmed by the capture of 16 specimens.&#13; Despite the new localities discovered, the species should still be considered as ‘Critically Endangered’ in Andalusia.&#13; &#13; &lt;strong&gt;Riassunto&lt;/strong&gt;&#13; &lt;strong&gt;Revisione della distribuzione dell'arvicola di Cabrera (&lt;em&gt;Microtus cabrerae&lt;/em&gt; Thomas 1906) in Andalusia (Spagna meridionale)&lt;/strong&gt;&#13; Il presente articolo consiste di una revisione dei dati disponibili sull'arvicola di Cabrera &lt;em&gt;Microtus cabrerae&lt;/em&gt; in Andalusia (Spagna meridionale) e fornisce dati originali ottenuti tramite un'indagine svolta sia in aree già investigate, sia in aree mai monitorate in precedenza. L'arvicola di Cabrera è stata individuata solo in 3 delle 17 località segnalate in letteratura, mentre in 12 di esse potrebbe essere estinta. I risultati ottenuti suggeriscono che la specie sia attualmente scomparsa dalla porzione centrale della provincia di Granada. Tuttavia, le indagini hanno permesso di rilevare la presenza della specie in 138 nuove località distribuite in 24 quadrati UTM 10x10 km corrispondenti alla cetena montuosa di Cazorla-Segura e all'estrema parte settentrionale delle province di Almeria e Granada. In 13 quadrati la presenza è stata confermata tramite la cattura di 16 individui. Nonostante la scoperta di questi nuovi nuclei, la specie deve essere tuttora considerata "in pericolo critico"in Andalusia

    Descriptive statistics for oxidative stress biomarkers.

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    <p>Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS), in serum from wild boar experimentally infected with <i>M</i>. <i>bovis</i>. The SOD, CAT, GPX and GR enzymes were measured in units of activity per mg of protein (U/mg), and TBARS in nanomoles of malondialdehyde per ml (nmol MDA/ml).</p
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