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1.
Conserv Biol ; 38(4): e14247, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38488677

RESUMEN

Climate change is one of the most important drivers of ecosystem change, the global-scale impacts of which will intensify over the next 2 decades. Estimating the timing of unprecedented changes is not only challenging but is of great importance for the development of ecosystem conservation guidelines. Time of emergence (ToE) (point at which climate change can be differentiated from a previous climate), a widely applied concept in climatology studies, provides a robust but unexplored approach for assessing the risk of ecosystem collapse, as described by the C criterion of the International Union for Conservation of Nature's Red List of Ecosystems (RLE). We identified 3 main theoretical considerations of ToE for RLE assessment (degree of stability, multifactorial instead of one-dimensional analyses, and hallmarks of ecosystem collapse) and 4 sources of uncertainty when applying ToE methodology (intermodel spread, historical reference period, consensus among variables, and consideration of different scenarios), which aims to avoid misuse and errors while promoting a proper application of the framework by scientists and practitioners. The incorporation of ToE for the RLE assessments adds important information for conservation priority setting that allows prediction of changes within and beyond the time frames proposed by the RLE.


Perspectivas sobre el momento del colapso ecosistémico en un clima cambiante Resumen El cambio climático es uno de los principales causantes del cambio ecosistémico, cuyo impacto a escala global se intensificará en las próximas dos décadas. No sólo es un reto estimar el momento de los cambios sin precedentes, sino también es de gran importancia para el desarrollo de las directrices de conservación de los ecosistemas. El momento de aparición (MdA), el punto en el que el cambio climático puede diferenciarse de un clima previo; es un concepto de aplicación extensa en los estudios de climatología y proporciona una estrategia sólida pero poco explorada para evaluar el riesgo del colapso ecosistémico, como está descrito por el criterio C de la Lista Roja de Ecosistemas (LRE) de la Unión Internacional para la Conservación de la Naturaleza. Identificamos las tres consideraciones teóricas del MdA para la evaluación de la LRE (grado de estabilidad, análisis multifactoriales en vez de unidimensionales y distintivos del colapso ecosistémico) y cuatro fuentes de incertidumbre cuando se aplica la metodología MdA (difusión intermodelo, periodo de referencia histórica, consenso entre las variables y consideración de escenarios distintos), la cual busca evitar el mal uso y los errores mientras se promueve una aplicación adecuada del marco de los científicos y lo practicantes. La incorporación del MdA a las evaluaciones de la LRE añade información importante para el establecimiento de prioridades de conservación que permiten la predicción de cambios dentro y más allá del marco temporal propuesto por la LRE.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Conservación de los Recursos Naturales/métodos , Factores de Tiempo , Incertidumbre
2.
Adv Exp Med Biol ; 1428: 149-177, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37466773

RESUMEN

Evidence from preclinical and clinical studies demonstrate that pregnancy is a physiological state capable of modifying drug disposition. Factors including increased hepatic metabolism and renal excretion are responsible for impacting disposition, and the role of membrane transporters expressed in biological barriers, including the placental- and blood-brain barriers, has received considerable attention. In this regard, the brain disposition of drugs in the mother and fetus has been the subject of studies attempting to characterize the mechanisms by which pregnancy could alter the expression of ATP-binding cassette (ABC) and solute carrier (SLC) transporters. This chapter will summarize findings of the influence of pregnancy on the maternal and fetal expression of ABC and SLC transporters in the brain and the consequences of such changes on the disposition of therapeutic drugs.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Placenta , Femenino , Embarazo , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Placenta/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Feto , Barrera Hematoencefálica/metabolismo , Adenosina Trifosfato/metabolismo
3.
Risk Anal ; 43(1): 8-18, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36509703

RESUMEN

Contrasting effects have been identified in association of weather (temperature and humidity) and pollutant gases with COVID-19 infection, which could be derived from the influence of lockdowns and season change. The influence of pollutant gases and climate during the initial phases of the pandemic, before the closures and the change of season in the northern hemisphere, is unknown. Here, we used a spatial-temporal Bayesian zero-inflated-Poisson model to test for short-term associations of weather and pollutant gases with the relative risk of COVID-19 disease in China (first outbreak) and the countries with more cases during the initial pandemic (the United States, Spain and Italy), considering also the effects of season and lockdown. We found contrasting association between pollutant gases and COVID-19 risk in the United States, Italy, and Spain, while in China it was negatively associated (except for SO2 ). COVID-19 risk was positively associated with specific humidity in all countries, while temperature presented a negative effect. Our findings showed that short-term associations of air pollutants with COVID-19 infection vary strongly between countries, while generalized effects of temperature (negative) and humidity (positive) with COVID-19 was found. Our results show novel information about the influence of pollution and weather on the initial outbreaks, which contribute to unravel the mechanisms during the beginning of the pandemic.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Ambientales , Humanos , Estados Unidos/epidemiología , COVID-19/epidemiología , España/epidemiología , Teorema de Bayes , Control de Enfermedades Transmisibles , Contaminación del Aire/análisis , Tiempo (Meteorología) , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Italia/epidemiología , China/epidemiología , Brotes de Enfermedades , Gases , Material Particulado/análisis
4.
Int J Mol Sci ; 22(6)2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33808976

RESUMEN

The mammalian hippocampal dentate gyrus is a unique memory circuit in which a subset of neurons is continuously generated throughout the lifespan. Previous studies have shown that the dentate gyrus neuronal population can hold fear memory traces (i.e., engrams) and that adult-born neurons (ABNs) support this process. However, it is unclear whether ABNs themselves hold fear memory traces. Therefore, we analyzed ABN activity at a population level across a fear conditioning paradigm. We found that fear learning did not recruit a distinct ABN population. In sharp contrast, a completely different ABN population was recruited during fear memory retrieval. We further provide evidence that ABN population activity remaps over time during the consolidation period. These results suggest that ABNs support the establishment of a fear memory trace in a different manner to directly holding the memory. Moreover, this activity remapping process in ABNs may support the segregation of memories formed at different times. These results provide new insight into the role of adult neurogenesis in the mammalian memory system.


Asunto(s)
Consolidación de la Memoria/fisiología , Memoria/fisiología , Neurogénesis/genética , Neuronas/metabolismo , Animales , Condicionamiento Psicológico , Giro Dentado/metabolismo , Giro Dentado/fisiología , Miedo/fisiología , Hipocampo/metabolismo , Hipocampo/fisiología , Humanos , Aprendizaje/fisiología , Ratones , Neuronas/fisiología
5.
Rev Med Chil ; 149(7): 1036-1046, 2021 Jul.
Artículo en Español | MEDLINE | ID: mdl-34751306

RESUMEN

Drug disposition in the human body is strongly influenced by transporters and metabolizing enzymes expressed in key organs including intestine, liver and kidney. Since drugs and chemicals present in foods such as fruit juices and herb-based products are substrates of the above-mentioned proteins, there is a high probability of pharmacokinetic interactions. Findings from preclinical and clinical studies helped to characterize the mechanisms by which the components of fruit juices and herbs act as perpetrators of pharmacokinetic interactions. The aim of this review is to provide an overview of pharmacokinetic fruit juice- and herb-drug interactions that could be relevant in the clinical setting.


Asunto(s)
Jugos de Frutas y Vegetales , Preparaciones de Plantas , Frutas , Interacciones de Hierba-Droga , Humanos , Preparaciones de Plantas/efectos adversos
6.
Purinergic Signal ; 16(3): 427-437, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32808144

RESUMEN

We aim to investigate the role of A2A receptor in peritonitis-related sepsis by injection of a fecal solution (FS) as a model of polymicrobial infection. C57/black J6 wild-type (WT) and A2A-deficient mice (A2AKO) were exposed to sepsis induced by intraperitoneal injection of a FS (FS-induced peritonitis) or instead was injected with saline buffer (Sham). Survival rate and sepsis score were measured up to 48 h. The presence of bacteria in tissue homogenates was analyzed. Telemetry and speckle laser Doppler were used for systemic blood pressure and peripheral blood perfusion analysis, respectively. Histological analysis and identification of active caspase 3 were performed in selected organs, including the liver. The survival rate of A2AKO mice exposed to FS-induced peritonitis was significantly higher, and the sepsis score was lower than their respective WT counterpart. Injection of FS increases (50 to 150 folds) the number of colonies forming units in the liver, kidney, blood, and lung in WT mice, while these effects were significantly attenuated in A2AKO mice exposed to FS-induced peritonitis. A significant reduction in both systolic and diastolic blood pressure, as well as in the peripheral perfusion was observed in WT and A2AKO mice exposed to FS-induced peritonitis. Although, these last effects were significantly attenuated in A2AKO mice. Histological analysis showed a large perivascular infiltration of polymorphonuclear in the liver of WT and A2AKO mice exposed to FS-induced peritonitis, but again, this effect was attenuated in A2AKO mice. Finally, high expression of active caspase 3 was found only in the liver of WT mice exposed to FS-induced peritonitis. The absence of the A2A receptor increases the survival rate in mice exposed to polymicrobial sepsis. This outcome was associated with both hemodynamic compensation and enhanced anti-bacterial response.


Asunto(s)
Peritonitis/metabolismo , Receptor de Adenosina A2A/metabolismo , Sepsis/metabolismo , Animales , Presión Sanguínea/fisiología , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados , Peritonitis/genética , Peritonitis/microbiología , Peritonitis/mortalidad , Receptor de Adenosina A2A/genética , Sepsis/genética , Sepsis/mortalidad , Tasa de Supervivencia
7.
Risk Anal ; 40(3): 524-533, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31578757

RESUMEN

Cryptococcus is an important fungal pathogen worldwide, causing serious clinical manifestations that can affect immunocompetent patients and can be particularly severe for immunocompromised patients. The Cryptococcus gattii s.s. (AFLP4/VGI), Cryptococcus tetragattii (AFLP/VGIV), Cryptococcus neoformans, and Cryptococcus deneoformans have been isolated from both clinical and environmental sources in Europe. We aim to quantify the people in Europe and the entire Mediterranean area who are under risk associated with each of the three fungal pathogens in a spatially explicit way, generating a series of maps and population statistics per country. Niche modeling was applied to estimate the potential distribution of each fungal pathogen, then these models were overlapped with a map of population density to estimate risk levels. The potential number of people per risk level and per country was quantified using a map of population count per pixel. Prevalence of HIV per country was also included in the analysis to quantify the HIV-infected population under potential risk. People under risk associated with exposure to C. gattii species (C. gattii s.s. and C. tetragattii) reached 137.65 million, whereas those exposed to C. neoformans and C. deneoformans were 268.58 and 360.78 million people, respectively. More than a half million HIV-infected patients are exposed to each of the two species of the C. neoformans species complex, and more than 200,000 to the C. gattii species complex. The present results can be useful for public health planning by European governments, focusing on the provision of inputs for a "screen-and-treat" approach, availability of medical resources, and continuous monitoring programs in risk zones.


Asunto(s)
Criptococosis/epidemiología , Cryptococcus gattii/patogenicidad , Cryptococcus neoformans/patogenicidad , Infecciones por VIH/complicaciones , Inmunocompetencia , Criptococosis/microbiología , Europa (Continente) , Humanos , Factores de Riesgo
8.
Biochem Biophys Res Commun ; 517(3): 520-524, 2019 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-31376934

RESUMEN

Simultaneous imaging and manipulation of a genetically defined neuronal population can provide a causal link between its activity and function. Here, we designed a miniaturized microscope (or 'miniscope') that allows fluorescence imaging and optogenetic manipulation at the cellular level in freely behaving animals. This miniscope has an integrated optical connector that accepts any combination of external light sources, allowing flexibility in the choice of sensors and manipulators. Moreover, due to its simple structure and use of open source software, the miniscope is easy to build and modify. Using this miniscope, we demonstrate the optogenetic silencing of hippocampal CA1 neurons using two laser light sources-one stimulating a calcium sensor (i.e., jGCaAMP7c) and the other serving as an optogenetic silencer (i.e., Jaws). This new miniscope can contribute to efforts to determine causal relationships between neuronal network dynamics and animal behavior.


Asunto(s)
Región CA1 Hipocampal/metabolismo , Microscopía/instrumentación , Red Nerviosa/metabolismo , Neuroimagen/métodos , Neuronas/metabolismo , Optogenética/métodos , Animales , Conducta Animal/fisiología , Región CA1 Hipocampal/ultraestructura , Calcio/metabolismo , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Expresión Génica , Genes Reporteros , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Inyecciones Intraventriculares , Luz , Ratones , Microscopía/métodos , Red Nerviosa/ultraestructura , Neuroimagen/instrumentación , Neuronas/ultraestructura , Imagen Óptica/instrumentación , Imagen Óptica/métodos , Optogenética/instrumentación , Rodopsina/genética , Rodopsina/metabolismo
9.
Curr Hypertens Rep ; 21(9): 72, 2019 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-31375930

RESUMEN

PURPOSE OF REVIEW: To provide insight into the mechanisms underlying cerebral pathophysiology and to highlight possible methods for evaluation, screening, and surveillance of cerebral complications in preeclampsia. RECENT FINDINGS: The pathophysiology of eclampsia remains enigmatic. Animal studies show that the cerebral circulation in pregnancy and preeclampsia might be affected with increased permeability over the blood-brain barrier and altered cerebral blood flow due to impaired cerebral autoregulation. The increased blood pressure cannot be the only underlying cause of eclampsia and cerebral edema, since some cases of eclampsia arise without simultaneous hypertension. Findings from animal studies need to be confirmed in human tissues. Evaluation of brain alterations in preeclampsia and eclampsia is challenging and demands a multidisciplinary collaboration, since no single method can accurately and fully describe how preeclampsia affects the brain. Cerebral complications of preeclampsia are significant factors in maternal morbidity and mortality worldwide. No single method can accurately describe the full picture of how preeclampsia affects the brain vasculature and parenchyma. We recommend an international and multidisciplinary effort not only to overcome the issue of limited sample availability but also to optimize the quality of research.


Asunto(s)
Encefalopatías/fisiopatología , Encéfalo/fisiopatología , Preeclampsia/fisiopatología , Animales , Encefalopatías/etiología , Circulación Cerebrovascular , Eclampsia/fisiopatología , Femenino , Humanos , Hipertensión/fisiopatología , Embarazo
10.
Rev Med Chil ; 143(6): 809-11, 2015 Jun.
Artículo en Español | MEDLINE | ID: mdl-26230566

RESUMEN

Thrombotic thrombocytopenic purpura, an immune/non-immune thrombotic microangiopathy (TTP/TMA) is associated with high morbidity and mortality, even with appropriate treatment. In patients refractory to standard treatment with plasmapheresis there is no certainty about the best therapeutic strategy. This report shows our experience in eight refractory patients who survived after treatment with rituximab.


Asunto(s)
Púrpura Trombocitopénica Trombótica/tratamiento farmacológico , Rituximab/uso terapéutico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Rituximab/farmacocinética , Adulto Joven
11.
Oecologia ; 174(4): 1215-24, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24368708

RESUMEN

Strategies developed by organisms to maximize foraging efficiency have a strong influence on fitness. The way in which the range of food resources is exploited has served to classify species, populations and individuals from more specialist (narrow trophic niche) to more generalist (broad trophic niche). Recent studies have provided evidence that many of the considered generalist species/populations are actually composed of different specialist individuals (individual specialization). Even the existence of generalism as an adaptive strategy has been questioned. In this study, we investigated the relationship between trophic niche width, individual quality and offspring viability in a population of common kestrel Falco tinnunculus during 4 years. We showed that the diet of kestrels varied significantly among years and that individuals of better quality fed their offspring with a higher diversity of prey species and a higher amount of food. Moreover, body condition and immune response of nestlings were positively correlated with diversity of prey delivered by parents. Our study suggests that generalism has the potential to increase fitness and that broadening the trophic niche may be an adaptive strategy in unpredictable environments.


Asunto(s)
Dieta , Ecosistema , Falconiformes/fisiología , Conducta Predatoria , Animales , Tamaño Corporal , Falconiformes/inmunología , Femenino , Masculino , Modelos Biológicos , Dinámica Poblacional
12.
Environ Sci Pollut Res Int ; 31(8): 12257-12270, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38227262

RESUMEN

Although the abundance, survival, and pollination performance of honeybees are sensitive to changes in habitat and climate conditions, the processes by which these effects are transmitted to honey production and interact with beekeeping management are not completely understood. Climate change, habitat degradation, and beekeeping management affect honey yields, and may also interact among themselves resulting in indirect effects across spatial scales. We conducted a 2-year, multi-scale study on Chiloe Island (northern Patagonia), where we evaluated the most relevant environmental and management drivers of honey produced by stationary beekeepers. We found that the effects of microclimate, habitat, and management variables changed with the spatial scale. Among the environmental variables, minimum temperature, and cover of the invasive shrub, gorse (Ulex europaeus) had the strongest detrimental impacts on honey production at spatial scales finer than 4 km. Specialized beekeepers who adopted conventional beekeeping and had more mother colonies were more productive. Mean and minimum temperatures interacted with the percentage of mother colonies, urban cover, and beekeeping income. The gorse cover increased by the combination of high temperatures and the expansion of urban lands, while landscape attributes, such as Eucalyptus plantation cover, influenced beekeeping management. Results suggest that higher temperatures change the available forage or cause thermal stress to honeybees, while invasive shrubs are indicators of degraded habitats. Climate change and habitat degradation are two interrelated environmental phenomena whose effects on beekeeping can be mitigated through adaptive management and habitat restoration.


Asunto(s)
Miel , Abejas , Animales , Miel/análisis , Microclima , Apicultura/métodos , Ecosistema , Polinización
13.
Sci Total Environ ; : 177133, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39447911

RESUMEN

Although woodpeckers are known to forage in decaying trees, their contribution to internal wood decay is not well known. In this sense, non-destructive techniques for structural wood degradation provide an opportunity to quantitatively assess the role of woodpeckers in tree decay. We used sonic tomography to test that the trunks of living trees pecked by Magellanic woodpeckers show pronounced decay, which accelerates under environmental conditions favorable to wood-decaying fungi. The internal decomposition of wood and its decay rate were measured over four years on 156 living southern beech (Nothofagus) trees belonging to four dominant species of southern temperate forests in northern Patagonia. Half of these live trees had woodpecker feeding holes, while the rest served as controls. The percentage of decayed wood, although not severely decayed, increased in sections with the presence of woodpecker holes, but was also influenced by temperatures and biophysical variables such as elevation and topography. The trunk sections with woodpecker holes and exposed to intensive foraging showed accelerated inter-annual decay. Woodpecker foraging activity interacted with vegetation characteristics, resulting in accelerated wood decay in forest sites with an open canopy and exposed to water stress. Thus, sonic tomography provided evidence of a close relationship between woodpeckers and internal wood decomposition, suggesting a positive feedback mechanism regulated by forest disturbance. The approach used here can be extended to gain insight into the influence of woodpeckers on tree decay and mortality in regions experiencing severe drought and forest degradation, such as northern Patagonia.

14.
Front Neurosci ; 18: 1411334, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846713

RESUMEN

Background: Deep-learning-based brain age estimation using magnetic resonance imaging data has been proposed to identify abnormalities in brain development and the risk of adverse developmental outcomes in the fetal brain. Although saliency and attention activation maps have been used to understand the contribution of different brain regions in determining brain age, there has been no attempt to explain the influence of shape-related cortical structural features on the variance of predicted fetal brain age. Methods: We examined the association between the predicted brain age difference (PAD: predicted brain age-chronological age) from our convolution neural networks-based model and global and regional cortical structural measures, such as cortical volume, surface area, curvature, gyrification index, and folding depth, using regression analysis. Results: Our results showed that global brain volume and surface area were positively correlated with PAD. Additionally, higher cortical surface curvature and folding depth led to a significant increase in PAD in specific regions, including the perisylvian areas, where dramatic agerelated changes in folding structures were observed in the late second trimester. Furthermore, PAD decreased with disorganized sulcal area patterns, suggesting that the interrelated arrangement and areal patterning of the sulcal folds also significantly affected the prediction of fetal brain age. Conclusion: These results allow us to better understand the variance in deep learning-based fetal brain age and provide insight into the mechanism of the fetal brain age prediction model.

16.
Environ Sci Pollut Res Int ; 30(30): 76253-76262, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37310602

RESUMEN

The effect of environmental and socioeconomic conditions on the global pandemic of COVID-19 had been widely studied, yet their influence during the early outbreak remains less explored. Unraveling these relationships represents a key knowledge to prevent potential outbreaks of similar pathogens in the future. This study aims to determine the influence of socioeconomic, infrastructure, air pollution, and weather variables on the relative risk of infection in the initial phase of the COVID-19 pandemic in China. A spatio-temporal Bayesian zero-inflated Poisson model is used to test for the effect of 13 socioeconomic, urban infrastructure, air pollution, and weather variables on the relative risk of COVID-19 disease in 122 cities of China. The results show that socioeconomic and urban infrastructure variables did not have a significant effect on the relative risk of COVID-19. Meanwhile, COVID-19 relative risk was negatively associated with temperature, wind speed, and carbon monoxide, while nitrous dioxide and the human modification index presented a positive effect. Pollution gases presented a marked variability during the study period, showing a decrease of CO. These findings suggest that controlling and monitoring urban emissions of pollutant gases is a key factor for the reduction of risk derived from COVID-19.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Humanos , COVID-19/epidemiología , Contaminantes Atmosféricos/análisis , Pandemias , Teorema de Bayes , Material Particulado/análisis , Contaminación del Aire/análisis , Monóxido de Carbono/análisis , China/epidemiología , Monitoreo del Ambiente
17.
Br J Pharmacol ; 180(23): 3092-3109, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37476954

RESUMEN

BACKGROUND AND PURPOSE: Blood-brain barrier (BBB) ABCB1, ABCG2 and ABCC5 transporters influence central therapeutic drug distribution. Transporter expression is regulated by the NR3C1, NR1I3 and NR1I2 nuclear receptors, but their precise roles in brain are poorly understood. We investigated the effects of selective ligand-based activation of NR3C1, NR1I3, NR1I2 and NR2B1 in porcine brain endothelial cells (PBECs). EXPERIMENTAL APPROACH: Primary cultures of PBECs were exposed to NR3C1, NR1I3 and NR1I2 ligands and ABCB1, ABCG2 and ABCC5 transporter activities determined by measuring intracellular accumulation of fluorescent probes. Western blotting was used to determine the effects of receptor ligands on expression of ABCB1, ABCG2, ABCC5, NR1I2, NR1I3, NR3C1 and NR2B1. Fluorescent immunocytochemistry was employed to assess the effects of receptor ligands on the cellular localisation of NR1I2 and NR1I3. KEY RESULTS: The NR1I2 agonist rifampicin significantly up-regulated ABCG2 activity, which is counteracted by co-treatment with NR1I2 antagonist l-sulforaphane. The NR1I3 agonist 6-(4-chlorophenyl)-imidazo[2,1-b]thiazole-5-carbaldehyde and inverse agonist meclizine significantly down-regulated ABCB1, ABCG2 and ABCC5 activity. NR3C1 agonist dexamethasone significantly increased ABCB1, ABCG2 and ABCC5 activity and ABCG2 and ABCC5 protein expression, which was counteracted by co-treatment with the NR3C1 antagonist mifepristone. This first study demonstrates that NR1I3 and NR3C1 regulate ABCC5 activity and protein expression in BBB endothelial cells. CONCLUSIONS AND IMPLICATIONS: In PBECs, expression of key ATP-binding cassette (ABC) transporters and nuclear receptors is differentially regulated by NR1I3, NR1I2, NR3C1 and NR2B1. This will help to better understand the response of the BBB to physiological and pharmacological activation of nuclear receptors.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Barrera Hematoencefálica , Animales , Porcinos , Barrera Hematoencefálica/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Receptor X de Pregnano , Células Endoteliales/metabolismo , Agonismo Inverso de Drogas , Receptores Citoplasmáticos y Nucleares/metabolismo
18.
Sci Total Environ ; 903: 166130, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37579796

RESUMEN

Coastal wetlands are considered one of the most vulnerable ecosystems worldwide; the ecosystem services they provide and the conservation of their biodiversity are threatened. Despite the high ecological and socioenvironmental value of coastal wetlands, regional and national vulnerability assessments are scarce. In this study we aimed to assess the vulnerability of coastal wetlands in Chile from 18°S to 42°S (n = 757) under a multiscale approach that included drivers associated with climate change and land cover change. We assessed multiple drivers of vulnerability at three spatial scales (10 m, 100 m, and 500 m) by analyzing multiple remote sensing data (16 variables) on land cover change, wildfires, climatic variables, vegetation functional properties, water surface and importance for biodiversity. We constructed a multifactorial vulnerability index based on the variables analyzed, which provided a map of coastal wetland vulnerability. Then we explored the main drivers associated with the vulnerability of each coastal wetland by performing a Principal Components Analysis with Agglomerative Hierarchical Clustering, which allowed us to group coastal wetlands according to the drivers analyzed. We found that 42.6 ± 9.2 % of the coastal wetlands evaluated have high or very high vulnerability, with higher vulnerability at the 500 m scale (51.4 %). We identified four groups of coastal wetlands: two located in central Chile, mainly affected by climate change-associated drivers (41.9 ± 2.1 %), and one in central Chile which is affected by land cover change (52.8 ± 6.2 %); the latter has a lower vulnerability level. The most vulnerable coastal wetlands were located in central Chile. Our results present novel findings about the current vulnerability of coastal wetlands, which could be validated by governmental institutions in field campaigns. Finally, we believe that our methodological approach could be useful to generate similar assessments in other world zones.

19.
Vet Q ; 43(1): 1-7, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36409461

RESUMEN

Viral diseases jeopardize the health of wildlife in Chile. However, this country lacks health surveillance programs that allow for defining preventive measures to tackle such diseases. The objective of this study was to determine the occurrence and the genetic diversity of pestivirus, herpesvirus and adenovirus in pudus from Chile. Blood samples from wild (n=34) and captive (n=32) pudus were collected between 2011 and 2019 and analyzed through consensus PCR. All the samples were negative to pestivirus and adenovirus. Herpesvirus was confirmed in four captive, and one wild pudu. All four zoo animals share the same sequence for both polymerase and glycoprotein genes. Both sequences share a 100% identity with caprine herpesvirus-2, classifying them in the same cluster as the Macavirus group. In turn, novel sequences of the polymerase and glycoprotein B genes were obtained from the wild pudu. Our study reports the first evidence of CpHV-2 infection in Chile and South American ungulate populations. Further research will be necessary to assess the pathogenicity of CpHV-2 in this species. It is also urgently recommended that molecular, serological and pathological screening should be conducted in Chilean wild and captive pudus to understand the impact of the herpesvirus on their populations.


Asunto(s)
Ciervos , Gammaherpesvirinae , Animales , Humanos , Chile/epidemiología , Cabras , Pueblos Sudamericanos
20.
Hypertension ; 80(2): 242-256, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35920147

RESUMEN

Preeclampsia is a maternal syndrome characterized by the new onset of hypertension and proteinuria after 20 weeks of gestation associated with multisystemic complications, including brain alterations. Indeed, brain complications associated with preeclampsia are the leading direct causes of fetal and maternal morbidity and mortality, especially in low- and middle-income countries. In addition to the well-recognized long-term adverse cardiovascular effects of preeclampsia, women who have had preeclampsia have higher risk of stroke, dementia, intracerebral white matter lesions, epilepsy, and perhaps also cognitive decline postpartum. Furthermore, increasing evidence has also associated preeclampsia with similar cognitive and cerebral disorders in the offspring. However, the mechanistic links between these associations remain unresolved. This article summarizes the current knowledge about the cerebrovascular complications elicited by preeclampsia and the potential pathophysiological mechanisms involved, emphasizing the impaired brain vascular function in the mother and their offspring.


Asunto(s)
Hipertensión , Preeclampsia , Embarazo , Humanos , Femenino , Niño , Madres , Encéfalo , Periodo Posparto
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