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1.
Glob Environ Change ; 48: 97-107, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29606806

RESUMEN

Extreme climatic events are likely to become more frequent owing to global warming. This may put additional stress on critical infrastructures with typically long life spans. However, little is known about the risks of multiple climate extremes on critical infrastructures at regional to continental scales. Here we show how single- and multi-hazard damage to energy, transport, industrial, and social critical infrastructures in Europe are likely to develop until the year 2100 under the influence of climate change. We combine a set of high-resolution climate hazard projections, a detailed representation of physical assets in various sectors and their sensitivity to the hazards, and more than 1100 records of losses from climate extremes in a prognostic modelling framework. We find that damages could triple by the 2020s, multiply six-fold by mid-century, and amount to more than 10 times present damage of €3.4 billion per year by the end of the century due only to climate change. Damage from heatwaves, droughts in southern Europe, and coastal floods shows the most dramatic rise, but the risks of inland flooding, windstorms, and forest fires will also increase in Europe, with varying degrees of change across regions. Economic losses are highest for the industry, transport, and energy sectors. Future losses will not be incurred equally across Europe. Southern and south-eastern European countries will be most affected and, as a result, will probably require higher costs of adaptation. The findings of this study could aid in prioritizing regional investments to address the unequal burden of impacts and differences in adaptation capacities across Europe.

2.
Proc Natl Acad Sci U S A ; 111(10): 3889-94, 2014 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-24567400

RESUMEN

Despite its theoretical prominence and sound principles, integrated pest management (IPM) continues to suffer from anemic adoption rates in developing countries. To shed light on the reasons, we surveyed the opinions of a large and diverse pool of IPM professionals and practitioners from 96 countries by using structured concept mapping. The first phase of this method elicited 413 open-ended responses on perceived obstacles to IPM. Analysis of responses revealed 51 unique statements on obstacles, the most frequent of which was "insufficient training and technical support to farmers." Cluster analyses, based on participant opinions, grouped these unique statements into six themes: research weaknesses, outreach weaknesses, IPM weaknesses, farmer weaknesses, pesticide industry interference, and weak adoption incentives. Subsequently, 163 participants rated the obstacles expressed in the 51 unique statements according to importance and remediation difficulty. Respondents from developing countries and high-income countries rated the obstacles differently. As a group, developing-country respondents rated "IPM requires collective action within a farming community" as their top obstacle to IPM adoption. Respondents from high-income countries prioritized instead the "shortage of well-qualified IPM experts and extensionists." Differential prioritization was also evident among developing-country regions, and when obstacle statements were grouped into themes. Results highlighted the need to improve the participation of stakeholders from developing countries in the IPM adoption debate, and also to situate the debate within specific regional contexts.


Asunto(s)
Agricultura/métodos , Países en Desarrollo , Control de Plagas/métodos , Análisis de Varianza , Análisis por Conglomerados , Relaciones Comunidad-Institución , Recolección de Datos , Educación , Motivación , Competencia Profesional , Investigación
3.
Pflugers Arch ; 466(5): 915-24, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24043571

RESUMEN

The human intestinal pathogen Giardia lamblia is a flagellated unicellular protozoan with pronounced medical and biological relevance. However, the basic physiology of Giardia trophozoites has been sparsely studied, especially the electrical and ionic properties of their cellular membrane which are virtually unknown. In this study, we were able to record and characterize the macroscopic ionic currents of Giardia trophozoite membrane by electrophysiological methods of the patch clamp technique. Giardia trophozoites showed a high current density (∼600 pA/pF at -140 mV) that was activated upon hyperpolarization. This current was carried by a chloride-selective channel (I Cl-G) and it was the most important determinant of the membrane potential in Giardia trophozoites. Moreover, this conductance was able to carry other halide anions and the sequence of permeability was Br(-) > Cl(-) ≈ I(-) ≫ F(-). Besides the voltage-dependent inward-rectifying nature of I Cl-G, its activation and deactivation kinetics were comparable to those observed in ClC-2 channels. Extracellular pH modified the voltage-dependent properties of I Cl-G, shifting the activation curve from a V 1/2 = -79 ± 1 mV (pH 7.4) to -93 ± 2 mV (pH 8.4) and -112 ± 2 mV (pH 5.4). Furthermore, the maximal amplitude of I Cl-G measured at -100 mV showed dependence to external pH in a bell-shaped fashion reported only for ClC-2 channels. Therefore, our results suggest that I Cl-G possesses several functional properties similar to the mammalian ClC-2 channels.


Asunto(s)
Potenciales de Acción , Canales de Cloruro/metabolismo , Giardia lamblia/metabolismo , Proteínas Protozoarias/metabolismo , Trofozoítos/metabolismo , Canales de Cloruro CLC-2 , Cloruros/metabolismo , Giardia lamblia/crecimiento & desarrollo , Giardia lamblia/fisiología , Potenciales de la Membrana , Trofozoítos/fisiología
4.
Nutr Neurosci ; 15(2): 62-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22333997

RESUMEN

UNLABELLED: One of the main concerns regarding organophosphate pesticides (OP) is their possible toxic effects. Doses that do not produce acute toxicity are capable of altering the structure and biochemistry of different tissues and organs by production of reactive oxygen species (ROS). Curcumin (CUR) is the main substance in Curcuma longa (Zingiberacea) rhizome that has strong antioxidant activity. However, the neuroprotective properties of curcumin against oxidative stress induced by prolonged exposure to parathion (PAR) is not clear. OBJECTIVE: The present work evaluated the protective effect of curcumin against the oxidative damage induced in the rat hippocampus by the OP PAR. METHODS: Forty female Wistar rats were distributed in four groups as follows: exposed to PAR by inhalation (PAR group); pre-treated with CUR and then exposed to PAR by inhalation, (CUR + PAR group); exposed to environmental air and treated with CUR in the food (CUR group); and exposed to environmental air (the control group). At the end of the handling process, the concentration of erythrocyte cholinesterase was monitored, as indicator of PAR intoxication and lipoperoxidation, immunohistochemistry for astrocytes, and activated microglia and apoptosis was determined in the hippocampus. RESULTS: In the present study, we show that the administration of CUR (200 mg/kg body weight) significantly diminished the oxidative damage in the hippocampus of rats exposed to the OP PAR. DISCUSSION: These data suggest that CUR may be an alternative to prevent neurodegenerative damage after pesticide exposure.


Asunto(s)
Curcumina/farmacología , Hipocampo/efectos de los fármacos , Insecticidas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Paratión/toxicidad , Extractos Vegetales/farmacología , Animales , Antioxidantes/farmacología , Curcuma/química , Femenino , Hipocampo/patología , Degeneración Nerviosa/prevención & control , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo
5.
Brain Res Bull ; 74(1-3): 113-8, 2007 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-17683796

RESUMEN

Glioma cell line C6, transfected with tyrosine hydroxylase (TH) cDNA under the control of the glial fibrillary acid protein promoter (C6-THA cells), elicited a reduction in the apomorphine-induced turning behavior when they are implanted in Parkinson's disease models. Nevertheless, dopamine (Da) release has not been explicitly demonstrated nor has a possible mechanism of release been implicated. In this study, the in vitro Da release by C6 and C6-THA cells after chemical stimulation with KCl or glutamate was quantified using HPLC. Modifications in intracellular calcium levels in response to KCl stimulation and participation of Da receptor-mediated feedback in calcium regulation were also studied using FLUO 3 as a calcium concentration indicator. C6-THA cells release dopamine in basal conditions, and increase its release after KCl or glutamic acid stimulation. In a fraction of C6 and C6-THA cells, a transient intracellular calcium increase was observed after KCl stimulation, but C6-THA cells demonstrated a faster rate of calcium removal. C6 cells express mRNA from all five subtypes of Da receptors as demonstrated by real time PCR. D1 receptors were most abundant in C6 cells and its expression was further increased in C6-THA cells. Blocking D1-like receptors in C6-THA cells with the specific antagonist drug SCH-23390 induced a decrease in intracellular calcium removal rate, resembling non-manipulated C6 cells' calcium clearance. Da release by C6-THA cells could be related to calcium dependent mechanisms. Furthermore, production of Da by C6-THA cells seems to upregulate the expression of D1 receptors' mRNA.


Asunto(s)
Calcio/metabolismo , Dopamina/metabolismo , Espacio Intracelular/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Análisis de Varianza , Animales , Benzazepinas/farmacología , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión/métodos , Antagonistas de Dopamina/farmacología , Glioma/patología , Ácido Glutámico/farmacología , Espacio Intracelular/efectos de los fármacos , Ratones , Cloruro de Potasio/farmacología , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Estadísticas no Paramétricas , Transfección/métodos , Tirosina 3-Monooxigenasa/genética
6.
Vet J ; 173(2): 428-36, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16459111

RESUMEN

Pig neural cells express glycoproteins with sialylated N-linked oligosaccharide chains (SNOC) which are used by the porcine rubulavirus (PoRv) as receptors. Pig neuronal or glial cell cultures were employed to investigate (a) whether PoRv infects such cells using a molecule expressing SNOC, and (b) the role of viral envelope glycoproteins in establishing the infection. Enriched neuronal or glial cell cultures were exposed to PoRv and infection was detected immunocytochemically. Neuronal cultures prepared from neonatal pigs were treated enzymatically to eliminate sialic acid or N-linked oligosaccharide chains. Primary neural cultures were exposed to anti-HN or anti-F preincubated with PoRv to study the role of the viral glycoproteins. In enriched cultures, PoRv infected neurons and glial cells, and sialic acid expressed in N-linked oligosaccharide chains appeared to play a central role in infection. It was concluded that HN and F viral glycoproteins are required to infect neurons and glial cells.


Asunto(s)
Neuroglía/virología , Neuronas/virología , Infecciones por Rubulavirus/veterinaria , Rubulavirus/fisiología , Sialoglicoproteínas/metabolismo , Animales , Encéfalo/citología , Células Cultivadas , Neuraminidasa/metabolismo , Neuroglía/citología , Neuroglía/metabolismo , Neuronas/citología , Neuronas/metabolismo , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/metabolismo , Receptores Virales/metabolismo , Infecciones por Rubulavirus/virología , Porcinos , Enfermedades de los Porcinos/virología , Proteínas del Núcleo Viral/metabolismo
7.
J Appl Genet ; 47(4): 377-82, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17132903

RESUMEN

Dietary polyphenolics, such as curcumin, have shown antioxidant and anti-inflammatory effects. Some antioxidants cause DNA strand breaks in excess of transition metal ions, such as copper. The aim of this study was to evaluate the in vitro effect of curcumin in the presence of increasing concentrations of copper to induce DNA damage in murine leukocytes by the comet assay. Balb-C mouse lymphocytes were exposed to 50 microM curcumin and various concentrations of copper (10 microM, 100 microM and 200 microM). Cellular DNA damage was detected by means of the alkaline comet assay. Our results show that 50 microM curcumin in the presence of 100-200 microM copper induced DNA damage in murine lymphocytes. Curcumin did not inhibit the oxidative DNA damage caused by 50 microM H2O2 in mouse lymphocytes. Moreover, 50 microM curcumin alone was capable of inducing DNA strand breaks under the tested conditions. The increased DNA damage by 50 mM curcumin was observed in the presence of various concentrations of copper, as detected by the alkaline comet assay.


Asunto(s)
Cobre/toxicidad , Curcumina/toxicidad , Daño del ADN , Animales , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Femenino , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Ratones , Ratones Endogámicos BALB C
9.
Vet. Méx ; 23(1): 41-6, ene.-mar. 1992. ilus, tab
Artículo en Español | LILACS | ID: lil-118346

RESUMEN

Se evaluó un método de castración no quirúrgico por inyección intratesticular en lechones de 21 días de edad. Cinco grupos experimentales fueron tratados con diferentes mezclas. Un grupo fue inyectado con formaldehido, xilocaína, epinefrina y propilenglicol (FXEP), otro con xilocaína y propolenglicol (XP), otro con epinefrina y propilenglicol (EP), otro con propilenglicol (P) y otro con formaldehido en solución amortiguadora de fosfatos 0.1 M (F). Se inyectó 1.5 ml de cada mezcla experimental en cada testículo de los lechones según su grupo. El tratamiento EP luego de 30 Días causó necrosis completa, a 90 y 180 días postratamiento se observó fibrosis, lo cual revela probablemente atrofia irreversible de ambos testículos. Asimismo, dichoo tratamiento produjo severa reducción del peso testicular, sin embargo, no se observaron efectos colaterales indeseables. El tratamiento no afectó el peso somático. En los otros grupos experimentales no se obtuvieron resultados satisfactorios sobre la atrofia y reducción de peso testicular. La preparación experimental no es costosa, la técnica de inyección es sencilla y facíl de realizar, y podría ser un modelo rápido y efectivo de castración no quirúrgica. Sin embargo, se encuentra aún en fase experimental.


Asunto(s)
Animales , Masculino , Glicoles de Propileno/uso terapéutico , Porcinos/cirugía , Epinefrina/uso terapéutico , Castración/métodos , Formaldehído/uso terapéutico , Lidocaína/uso terapéutico
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