Search results for "Ciencias Biológicas"
showing 10 items of 794 documents
Human apolipoprotein A-I Gly26Arg stimulation of inflammatory responses via NF-kB activation: Potential roles in amyloidosis?
2018
The cascade of molecular events leading to Human apolipoprotein A–I (apoA–I) amyloidosis is not completely understood, not even the pathways that determine clinical manifestations associated to systemic protein deposition in organs such as liver, kidney and heart. About twenty natural variants of apoA–I were described as inducing amyloidosis, but the mechanisms driving their aggregation and deposition are still unclear. We previously identified that the mutant Gly26Arg but not Lys107-0 induced the release of cytokines and reactive oxygen species from cultured RAW 264.7 murine macrophages, suggesting that part of the pathogenic pathway could elicit of an inflammatory signal. In this work we …
Morphology, performance and attachment function in Corynosoma spp. (Acanthocephala)
2018
Background: Functional inference on the attachment of acanthocephalans has generally been drawn directly from morphology. However, performance of structures is often non-intuitive and context-dependent, thus performance analysis should be included whenever possible to improve functional interpretation. In acanthocephalans, performance analysis of attachment is available only for Acanthocephalus ranae, a species that solely relies on the proboscis to attach. Here we compare body morphology and muscle arrangement in 13 species of Corynosoma, which use their spiny body as a fundamental holdfast. A basic performance analysis using live cystacanths of two representative species is also provided.…
From mammals back to birds: Host-switch of the acanthocephalan Corynosoma australe from pinnipeds to the Magellanic penguin Spheniscus magellanicus.
2017
Trophically-transmitted parasites are regularly exposed to potential new hosts through food web interactions. Successful colonization, or switching, to novel hosts, occur readily when ?donor? and ?target? hosts are phylogenetically related, whereas switching between distantly related hosts is rare and may result from stochastic factors (i.e. rare favourable mutations). This study investigates a host-switching event between a marine acanthocephalan specific to pinnipeds that is apparently able to reproduce in Magellanic penguins Spheniscus magellanicus from Brazil. Detailed analysis of morphological and morphometrical data from acanthocephalans from penguins indicates that they belong to Cor…
Cestode parasites release extracellular vesicles with microRNAs and immunodiagnostic protein cargo.
2017
Intercellular communication is crucial in multiple aspects of cell biology. This interaction can be mediated by several mechanisms including extracellular vesicle (EV) transfer. EV secretion by parasites has been reported in protozoans, trematodes and nematodes. Here we report that this mechanism is present in three different species of cestodes, Taenia crassiceps, Mesocestoides corti and Echinococcus multilocularis. To confirm this we determined, in vitro, the presence of EVs in culture supernatants by transmission electron microscopy. Interestingly, while T. crassiceps and M. corti metacestodes secrete membranous structures into the culture media, similar vesicles were observed in the int…
Mandarin essential oils inhibit quorum sensing and virulence factors of Pseudomonas aeruginosa
2016
Pseudomonas aeruginosa produces biofilm and several virulence factors coordinated by quorum sensing (QS) in food. The interruption of QS is a target to control the bacterial virulence. Chemical preservatives used to control biofilm give rise to several food safety problems. For this reason, essential oils (EOs), generally recognized as safe products, are a hopeful alternative. The aim of this work was to determine the chemical composition of mandarin EOs obtained by cold-pressing (EOP) and cold-pressing followed by steam distillation (EOPD) and their antipathogenic properties against P. aeruginosa. Both EOs contained the highest quantities of monoterpene hydrocarbons, mainly limonene, follo…
The genomic sequence of Exiguobacterium chiriqhucha str. N139 reveals a species that thrives in cold waters and extreme environmental conditions
2017
We report the genome sequence of Exiguobacterium chiriqhucha str. N139, isolated from a high-altitude Andean lake. Comparative genomic analyses of the Exiguobacterium genomes available suggest that our strain belongs to the same species as the previously reported E. pavilionensis str. RW-2 and Exiguobacterium str. GIC 31. We describe this species and propose the chiriqhucha name to group them. ‘Chiri qhucha’ in Quechua means ‘cold lake’, which is a common origin of these three cosmopolitan Exiguobacteria. The 2,952,588-bp E. chiriqhucha str. N139 genome contains one chromosome and three megaplasmids. The genome analysis of the Andean strain suggests the presence of enzymes that confer E. ch…
Dos nuevas localidades de orquídeas raras en la Marina Baixa (Alicante).
2002
Se dan a conocer nuevas localidades de dos orquídeas raras en el ámbito de la Comunidad Valenciana. Por un lado, Orchis italica Poir. [= O. longicruris Link] supone la primera cita conocida para la comarca de la Marina Baixa, donde alcanza su extremo de distribución meridional. Por otro lado, la referencia a Serapias parviflora Parl. [= S. occultata Gay ex Cav.], especie localmente muy amenazada en la Comunidad Valenciana, amplía su distribución conocida en la provincia de Alicante. Para ambas se aportan datos sobre su ecología y estado de conservación, y además se propone la creación de microrreservas de flora que aseguren su presencia en las comarcas alicantinas. New localities of two rar…
Recatalogación de Vella lucentina M.B. Crespo (Cruciferae) según las categorías UICN (2001)
2006
Vella lucentina es un endemismo del centro de la provincia de Alicante que habita en matorrales esteparios calcícolas, bajo bioclima termomediterráneo semiárido. Su fragmentada área de ocupación apenas alcanza tres kilómetros cuadrados y se encuentra sometida a una fuerte presión antrópica, por lo que hasta el momento se tiene como especie “vulnerable” (VU), según las categorías de amenaza de la UICN. Sin embargo, últimamente se ha constatado una merma en la calidad de su hábitat y la desaparición de algunos núcleos poblacionales secundarios, a causa a actividades urbanísticas que amenazan a las restantes poblaciones. Los trabajos que se vienen realizando en los últimos meses sobre la biolo…
Adiciones a la flora alicantina, IV
2002
Se comentan algunas especies de plantas vasculares recolectadas en la provincia de Alicante, que resultan nuevas o raras. Some new or rare species of vascular plants founded in Alicante province are commented. Trabajo financiado con cargo al proyecto LIFE “Conservación de Hábitats prioritarios en la Comunidad Valenciana”.
Sobre algunos endemismos ibéricos presentes en las áreas setabenses
1999
Se aportan nuevos datos sobre la distribución de seis endemismos ibéricos presentes en las áreas setabenses de las provincias de Alicante y Valencia. En todos los casos se trata de ampliaciones notables de sus áreas de distribución y, en el caso de Hippocrepis valentina y Centaurea segariensis, novedades para el catálogo provincial de Valencia. Para todas ellas, se aportan datos sobre su ecología, fitosociología y biogeografía. New data on distribution of six Spanish endemics growing in the Setabensian areas of Valencia and Alicante provinces (E of Spain), are reported. The distribution areas of most of them are considerably enlarged, and both Hippocrepis valentina and Centaurea segariensis…