7 research outputs found

    Pathogenesis and transmission of lymphocystis disease virus (LCDV) in gilthead seabream (Sparus aurata L.)

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    La enfermedad de linfocistis (LCD) se ha descrito en más de 140 especies diferentes de peces teleósteos, tanto marinos como dulceacuícolas, y tiene una amplia distribución geográfica. Su agente etiológico es el virus de la enfermedad de linfocistis (LCDV), género Lymphocystivirus, familia Iridoviridae. Esta enfermedad se caracteriza por la aparición de unos pequeños nódulos parecidos a papilomas localizados en la superficie del cuerpo y las aletas, que pueden aparecer aislados o más frecuentemente agrupados en racimos, pudiendo llegar a cubrir todo el cuerpo del animal. En las instalaciones de acuicultura la LCD suele presentar una elevada morbilidad, ocasionando graves pérdidas económicas relacionadas con la desfiguración de los animales que impide su comercialización. Existen pocos estudios realizados sobre la patogénesis del LCDV, limitados en su mayoría a estudios histopatológicos de las lesiones localizadas en la piel y en algunos órganos internos, pero no se ha descrito el curso de la infección ni el tropismo del virus. Por otra parte, la identificación de los reservorios del LCDV implicados en la transmisión del virus a larvas y juveniles de dorada también reviste gran importancia ya que permitiría abordar la eliminación de este patógeno en las piscifactorías. Los principales objetivos de esta tesis doctoral han sido el estudio de la patogénesis del LCDV en dorada, y el establecimiento de las rutas de transmisión del mismo en larvas y alevines de esta especie. Para la consecución de estos objetivos se han diseñado y evaluado técnicas moleculares que permiten determinar los órganos diana del LCDV en el hospedador. Estas herramientas se aplicaron también a la identificación de reservorios del virus en las instalaciones de cultivo larvario de dorada, y al estudio de su implicación en la transmisión vírica. Por último, se planteó establecer si la artemia es susceptible a la infección por LCDV. Se han diseñado, evaluado y aplicado protocolos de qPCR y RT-qPCR para la cuantificación de genoma y transcritos virales, un protocolo de ICC-RT-PCR para la detección y cuantificación de virus infectivos, protocolos de hibridación in situ para la detección de transcritos virales en secciones histológicas, y un protocolo LAMP que permite la detección rápida y económica del virus en piscifactorías. Por otra parte, se han realizado estudios histopatológicos en doradas infectadas con LCDV para establecer la presencia de alteraciones histológicas asociadas a la enfermedad Los resultados obtenidos indican que la infección por LCDV en juveniles de dorada presenta un carácter sistémico, tanto en infecciones sintomáticas como subclínicas. Además, el curso de la infección puede ser crónico, presentando los peces una infección persistente durante un periodo de tiempo indeterminado. El LCDV presenta un tropismo muy amplio, replicándose al menos en fibroblastos de la dermis, hepatocitos, células del tejido hematopoyético de bazo y riñón, y en el cerebro. Los cambios histopatológicos asociados con la LCD aparecen en diferentes órganos de alevines de dorada, y revierten cuando los peces se recuperan de la enfermedad. En cuanto a la transmisión del LCDV, se ha comprobado que los reproductores asintomáticos son portadores que podrían liberar partículas víricas en sus fluidos reproductivos y/o excreciones, provocando la transmisión del virus a las larvas. Además, los rotíferos constituyen un vector de infección para el LCDV. Por último, el LCDV provoca una infección productiva en Artemia, al menos en las condiciones experimentales utilizadas, lo cual extiende el rango de hospedador del LCDV a crustáceos. Además, los metanauplios de Artemia pueden actuar como vector para la transmisión del LCDV a doradas

    Artemia spp., a Susceptible Host and Vector for Lymphocystis Disease Virus.

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    Di erent developmental stages of Artemia spp. (metanauplii, juveniles and adults) were bath-challenged with two isolates of the Lymphocystis disease virus (LCDV), namely, LCDV SA25 (belonging to the species Lymphocystis disease virus 3) and ATCC VR-342 (an unclassified member of the genus Lymphocystivirus). Viral quantification and gene expression were analyzed by qPCR at di erent times post-inoculation (pi). In addition, infectious titres were determined at 8 dpi by integrated cell culture (ICC)-RT-PCR, an assay that detects viral mRNA in inoculated cell cultures. In LCDV-challenged Artemia, the viral load increased by 2–3 orders of magnitude (depending on developmental stage and viral isolate) during the first 8–12 dpi, with viral titres up to 2.3 102 Most Probable Number of Infectious Units (MPNIU)/mg. Viral transcripts were detected in the infected Artemia, relative expression values showed a similar temporal evolution in the di erent experimental groups. Moreover, gilthead seabream (Sparus aurata) fingerlings were challenged by feeding on LCDV-infected metanauplii. Although no Lymphocystis symptoms were observed in the fish, the number of viral DNA copies was significantly higher at the end of the experimental trial and major capsid protein (mcp) gene expression was consistently detected. The results obtained support that LCDV infects Artemia spp., establishing an asymptomatic productive infection at least under the experimental conditions tested, and that the infected metanauplii are a vector for LCDV transmission to gilthead seabream

    Persistence of Lymphocystis Disease Virus (LCDV) in Seawater

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    Lymphocystis disease virus (LCDV), the causative agent of lymphocystis disease (LCD), is a waterborne pathogen that uses the external surfaces, including the gills, as portals to gain access to fsh host. However, there are no data on LCDV persistence in the aquatic environment. In this study, the persistence of LCDV in natural (raw), treated (autoclaved and fltered) and synthetic seawater held at 22 and 18 °C has been evaluated. The estimated T99 values for LCDV in seawater ranged from 2.7 to 242 days depending on seawater type and temperature, with the highest value recorded at 22 °C in autoclaved seawater. Microbiota and temperature seem to be the main factors afecting the persistence of LCDV in seawater. The results indicated that LCDV is more stable in treated seawater than most of the fsh pathogenic viruses studied so far, supporting the relevance of this medium for the prevalence of LCD in fsh farms

    Infection of Artemia sp. by Lymphocystis disease virus (LCDV)

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    In the present work, different developmental stages of Artemia sp. (metanauplius, juvenile and adult) were experimentally infected with LCDV by immersion. Results of viral quantification (both by qPCR and cell-culture viral titer determination) and expression showed that LCDV establishes a productive infection in Artemia, at least under experimental conditions, extending the host range of this virus to crustaceans.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Statistical analysis plan for the multicenter, open, randomized controlled clinical trial to assess the efficacy and safety of intravenous tirofiban vs aspirin in acute ischemic stroke due to tandem lesion, undergoing recanalization therapy by endovascular treatment (ATILA trial)

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    © The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.[Rationale] In-stent reocclusion after endovascular therapy has a negative impact on outcomes in acute ischemic stroke (AIS) due to tandem lesions (TL). Optimal antiplatelet therapy approach in these patients to avoid in-stent reocclusion is yet to be elucidated.[Aims] To assess efficacy and safety of intravenous tirofiban versus intravenous aspirin in patients undergoing MT plus carotid stenting in the setting of AIS due to TL.[Sample size estimates] Two hundred forty patients will be enrolled, 120 in every treatment arm.[Methods and design] A multicenter, prospective, randomized, controlled (aspirin group), assessor-blinded clinical trial will be conducted. Patients fulfilling the inclusion criteria will be randomized at MT onset to the experimental or control group (1:1). Intravenous aspirin will be administered at a 500-mg single dose and tirofiban at a 500-mcg bolus followed by a 200-mcg/h infusion during the first 24 h. All patients will be followed for up to 3 months.[Study outcomes] Primary efficacy outcome will be the proportion of patients with carotid in-stent thrombosis within the first 24 h after MT. Primary safety outcome will be the rate of symptomatic intracranial hemorrhage.[Discussion] This will be the first clinical trial to assess the best antiplatelet therapy to avoid in-stent thrombosis after MT in patients with TL.[Trial registration] The trial is registered as NCT05225961. February, 7th, 2022.This project was funded by the Instituto de Salud Carlos III (ISCIII) through the project PI21/01322 and co-funded by the European Union. The Spanish Clinical Research Network (SCReNCode: 21.033) also contributed to the study. The ITRIBiS project (Improving Translational Research Potential at the Institute of Biomedicine of Seville) has the registration number REGPOT-2013-1. M. Medina-Rodríguez was granted a Rio Hortega contract (CM21/00096). The project was included in the Cooperative Cerebrovascular Disease Research Network (INVICTUS) (RD16/0019/0015).Peer reviewe

    Servicio de salud es una deuda pendiente en el territorio indígena de Alto Chirripó

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    Los servicios de salud en las comunidades indígenas presentan grandes limitaciones que afectan directamente a una de las poblaciones más desprotegidas de Costa Rica. A la falta de personal, infraestructura y equipo insuficiente en los puestos de salud, se le suma la ausencia de interculturización de los servicios de salud y de inclusión de los diversos actores culturales, quienes poseen un rol importante en las comunidades dentro de las tomas de decisiones. Tales factores limitan la reacción de las autoridades de salud, con lo cual se incrementan las posibilidades de contagio por covid-19.Health services in indigenous communities have great limitations that directly affect one of the most vulnerable populations in Costa Rica. In addition to the lack of personnel, infrastructure and insufficient equipment in the health posts, there is also the lack of interculturalization of the health services and the inclusion of the various cultural actors, who play an important role in the communities within the health services. decisions. Such factors limit the reaction of health authorities, thereby increasing the chances of contagion by covid-19.Universidad Nacional, Costa RicaEscuela de Psicologí

    Changes in floral biology and inbreeding depression in native and invaded regions of Datura stramonium

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    Plant populations invading new environments might compromise their fitness contribution to the next generation, because of the lack of native specialist pollinators and/or potential mates. Thus, changes in plant mating system and traits linked to it are expected in populations colonising new environments where selection would favour selfing and floral traits that maximise reproductive output. To test this, we studied native (Mexico) and non-native (Spain) populations of the obligate sexual reproducing annual weed Datura stramonium. Flower size, herkogamy, total number of seeds per plant, number of visits by and type of pollinators, and inbreeding depression were assessed in native and non-native populations. Finally, we measured phenotypic selection on corolla size and herkogamy in each population. Flower size and herkogamy showed wide and similar variation in both ranges. However, the largest average flower size was found in one non-native population whereas the highest average positive herkogamy was detected in one native population. On average, flowers in the native range received more visits by pollinators. Hawkmoths were the main visitors in the native populations while only bees were observed visiting flowers in Spain's populations. Only in the native range was inbreeding depression detected. Selection to reduce herkogamy was found only in one native population. Absence of both inbreeding depression and selection on floral traits suggest a change in mating system of D. stramonium in a new range where generalist pollinators may be promoting high reproductive success. Selection against deleterious alleles might explain the reduction of inbreeding depression, promoting the evolution of selfing.Ministerio de Economía y Competitividad CGL2013-45037-PUniversidad Nacional Autónoma de México IN21221
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