2,036 research outputs found

    Host-parasite dialogue: fecundity compensation mechanisms of Fissurella crassa

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    Parasites can alter the reproductive performance of their hosts, and to avoid or mitigate the resulting fitness loss, hosts may increase their current reproductive output to compensate for the future loss due to the parasitic infection. Fecundity compensation can be exploited by parasites for their own transmission (exploitation of host compensatory responses by parasites). However, this phenomenon has rarely been reported in second intermediate hosts of trematodes and its mechanisms and consequences largely unexplored. Along the east coast of the South Pacific, the second intermediate host, the mollusk Fissurella crassa, has been observed to display higher muscular foot, greater shell length and weight, and a higher gonadosomatic index when parasitized by metacercariaes of Proctoeces humboldti compared to non-parasitized hosts. In this study, we examined the histology, biochemistry (glucose, lipids, and proteins), and levels of sex hormones (estradiol and progesterone) in both parasitized and non-parasitized female individuals of F. crassa. Our findings revealed that the gonad of parasitized limpets had a higher density of oocytes, but these had a smaller individual area. Additionally, the gonadal tissue of parasitized limpets exhibited lower glucose content but higher lipid content. Notably, the levels of progesterone increased with parasite intensity. These results suggest that F. crassa possesses the ability to compensate for the negative effects of parasites by increasing the number of oocytes through biochemical and hormonal mechanisms. Our study contributes to the limited research on the impact of metacercariae on the reproduction of second intermediate hosts. Furthermore, we discuss how these changes in parasitized limpets could benefit parasite transmission

    Evolutionary ecology of obligate fungal and microsporidian invertebrate pathogens

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    The interactions between hosts and their parasites and pathogens are omnipresent in the natural world. These symbioses are not only key players in ecosystem functioning, but also drive genetic diversity through co-evolutionary adaptations. Within the speciose invertebrates, a plethora of interactions with obligate fungal and microsporidian pathogens exist, however the known interactions is likely only a fraction of the true diversity. Obligate invertebrate fungal and microsporidian pathogen require a host to continue their life cycle, some of which have specialised in certain host species and require host death to transmit to new hosts. Due to their requirement to kill a host to spread to a new one, obligate fungal and microsporidian pathogens regulate invertebrate host populations. Pathogen specialisation to a single or very few hosts has led to some fungi evolving the ability to manipulate their host’s behaviour to maximise transmission. The entomopathogenic fungus, Entomophthora muscae, infects houseflies (Musca domestica) over a week-long proliferation cycle, resulting in flies climbing to elevated positions, gluing their mouthparts to the substrate surface, and raising their wings to allow for a clear exit from fungal conidia through the host abdomen. These sequential behaviours are all timed to occur within a few hours of sunset. The E. muscae mechanisms used in controlling the mind of the fly remain relatively unknown, and whether other fitness costs ensue from an infection are understudied.European Commissio

    A small change with a twist ending: a single residue in EGF-CFC drives bilaterian asymmetry

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    This is a pre-copyedited, author-produced PDF of an article accepted for publication in Molecular biology and evolution following peer review. The version of record Molecular biology and evolution 40.2 (2023): msac270 is available online at: https://academic.oup.com/search-results?page=1&q=10.1093%2Fmolbev%2Fmsac270&fl_SiteID=191&SearchSourceType=1&allJournals=1Asymmetries are essential for proper organization and function of organ systems. Genetic studies in bilaterians have shown signaling through the Nodal/Smad2 pathway plays a key, conserved role in the establishment of body asymmetries. Although the main molecular players in the network for the establishment of left-right asymmetry (LRA) have been deeply described in deuterostomes, little is known about the regulation of Nodal signaling in spiralians. Here, we identified orthologs of the egf-cfc gene, a master regulator of the Nodal pathway in vertebrates, in several invertebrate species, which includes the first evidence of its presence in non-deuterostomes. Our functional experiments indicate that despite being present, egf-cfc does not play a role in the establishment of LRA in gastropods. However, experiments in zebrafish suggest that a single amino acid mutation in the egf-cfc gene in at least the common ancestor of chordates was the necessary step to induce a gain of function in LRA regulation. This study shows that the egf-cfc gene likely appeared in the ancestors of deuterostomes and "protostomes", before being adopted as a mechanism to regulate the Nodal pathway and the establishment of LRA in some lineages of deuterostome

    The mechanisms and factors that induce trained immunity in arthropods and mollusks

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    Besides dividing the organism’s immune system into adaptive and innate immunity, it has long been thought that only adaptive immunity can establish immune memory. However, many studies have shown that innate immunity can also build immunological memory through epigenetic reprogramming and modifications to resist pathogens’ reinfection, known as trained immunity. This paper reviews the role of mitochondrial metabolism and epigenetic modifications and describes the molecular foundation in the trained immunity of arthropods and mollusks. Mitochondrial metabolism and epigenetic modifications complement each other and play a key role in trained immunity

    Análisis ecotoxicológico del uso de nanopartículas magnéticas funcionalizadas con zeolita 5A y con CTAB en el biomarcador Daphnia magna (STRAUS, 1820)

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    Eval√ļa los posibles efectos biot√≥xicos en la sobrevivencia, desarrollo morfol√≥gico y tasa de reproducci√≥n de Daphnia magna generados por el uso de nanopart√≠culas de maghemita (ő≥-Fe2O3) puras, funcionalizadas con zeolita 5A y funcionalizadas con CTAB. El uso de nanopart√≠culas magn√©ticas (NPM) para remediar los ambientes dulceacu√≠colas contaminados con metales pesados, se ha vuelto objeto de inter√©s e investigaci√≥n en el campo de la toxicolog√≠a ambiental debido a sus propiedades t√≥xicas intr√≠nsecas. Se estudia las propiedades ecotoxicol√≥gicas de nanopart√≠culas (NP) de maghemita (ő≥-Fe2O3) puras, funcionalizadas con zeolita 5A y con bromuro de cetiltrimetilamonio (CTAB). Se realiza los procedimientos de s√≠ntesis por coprecipitaci√≥n qu√≠mica y funcionalizaci√≥n para producir cinco nanomateriales que se caracterizaron con diversas t√©cnicas fisicoqu√≠micas con el fin de garantizar sus propiedades de remediaci√≥n magn√©tica. Se obtiene nanopart√≠culas de ő≥- Fe2O3 puras y funcionalizadas con tama√Īos entre 4,5 y 12 nm, Despu√©s se realiza bioensayos ecotoxicol√≥gicos en el biomarcador de agua dulce Daphnia magna, para comprobar la toxicidad e impacto del posible uso de estos nanomateriales en ambientes dulceacu√≠colas. Los resultados muestran que las concentraciones letales medias (LC50) oscilaban entre 103,2 mg L-1 para las NP de ő≥-Fe2O3 puras y 0,5 mg L-1 para las NP funcionalizadas. El an√°lisis morfol√≥gico de los organismos sobrevivientes mostr√≥ cambios significativos en el coraz√≥n y algunas malformaciones en el ojo.Per√ļ. Universidad Nacional Mayor de San Marcos. Vicerrectorado de Investigaci√≥n y Posgrado. Proyecto VRIP-UNMSM MINEDU B2113002

    Assessing the immunomodulatory and haemostatic role of platelets in the type 2 inflammatory response to Schistosoma mansoni

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    Beyond their role in haemostasis, platelets have been shown to be strongly immunomodulatory, particularly in type 1 inflammatory responses to bacteria and viruses. However, the role of platelets in type 2 inflammation, that characterises helminth infection and allergy is poorly understood. More than 200 million people globally are chronically infected with schistosome parasites which has a massive burden of >3 million disability adjusted life years. Despite large (~1cm long) worms residing in the vasculature for 5-10 years, they do not induce severe inflammation or coagulation. However, infected individuals display a plethora of debilitating symptoms including hepatosplenomegaly and intestinal haemorrhaging due to thousands of schistosome eggs transiting through and lodging within host tissues. This thesis aims to assess the haemostatic alterations and functional consequences of platelet-immune cell cross-talk in schistosomiasis. We used a murine model of chronic Schistosoma mansoni infection to examine specific platelet-leukocyte interactions and the effect these have on inflammation. Chronic schistosome infection induces thrombocytopenia (~500x10^3/mm^3) that persists after drug-mediated worm clearance. In vivo platelet tracking revealed accelerated hepatic and splenic platelet clearance in schistosome infection, and this occurred in an Fcő≥R-independent manner. Furthermore, there was a significant increase in platelets aggregating with specific hepatic macrophage subsets (Ly6Cň°ŠĶí MHCIIň°ŠĶí RELMőĪ į‚ĀĪ). Live cell imaging in vitro experiments revealed that platelets enhanced the phagocytic ability of M2 macrophages without altering MHCII or RELMőĪ expression. Surprisingly, platelets from schistosome-infected mice spontaneously aggregated in the absence of exogenous agonists despite not having an activated platelet phenotype, yet show prolonged clotting time. We used multiple experimental strategies to deplete or increase platelet numbers in schistosome infection, and this highlighted the challenges of separating the haemostatic and immunological roles of platelets in vivo. Work in this thesis demonstrates how schistosome infection disrupts platelet lifespan and functionality, whilst promoting enhanced interactions with immune cells

    2017 GREAT Day Program

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    SUNY Geneseo’s Eleventh Annual GREAT Day.https://knightscholar.geneseo.edu/program-2007/1011/thumbnail.jp

    Socio-environmental impacts of non-native and transplanted aquatic mollusc species in South America: What do we really know?

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    The impacts of biological invasions remain poorly known for some habitats, regions and taxa. To date, there has been no comprehensive effort to review and synthesize the impacts of invasive mollusc species in South America. In this paper, we provide a synoptic view on what is known on documented socio-ecological impacts of aquatic no-native mollusc species (NNMS) and transplanted mollusc species (TMS) from South America. An expert group involving malacologists and taxonomists from different countries, the ‚ÄúSouth America Alien Molluscs Specialists‚ÄĚ (eMIAS), shared and summarized the scientific literature, databases, and published and unpublished information on confirmed impacts of NNMS and TMS in South America. Three broad categories, non-mutually exclusive were used as a framework: ‚ÄúEnvironmental/Biodiversity impacts‚ÄĚ, ‚ÄúEconomic and social effects‚ÄĚ, and ‚ÄúHuman health impacts‚ÄĚ. Some 21 NNMS and seven TMS have documented impacts on at least one of those three categories. We encourage targeting the less known areas of research, such as economic valuation of human health (and veterinary) impacts attributable to NNMS or TMS and expand our knowledge of environmental impacts for the species listed in this study.Fil: Carranza, Alvar. Universidad de la Rep√ļblica; Uruguay. Museo Nacional de Historia Natural Uruguay; UruguayFil: Agudo Padr√≥n, Ignacio. Projeto ‚Äúavulsos Malacol√≥gicos‚ÄĚ; BrasilFil: Collado, Gonzalo A.. Universidad del Bio Bio; Chile. Sociedad Malacol√≥gica Chile; ChileFil: Damborenea, Maria Cristina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Divisi√≥n Zoolog√≠a Invertebrados; Argentina. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - La Plata; ArgentinaFil: Fabres, Alejandra. Sociedad Malacol√≥gica Chile; Chile. Universidad Cat√≥lica de Maule; ChileFil: Gutierrez Gregoric, Diego Eduardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Divisi√≥n Zoolog√≠a Invertebrados; Argentina. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - La Plata; ArgentinaFil: Lodeiros, Cesar. Universidad T√©cnica de Manab√≠; Ecuador. Universidad de Oriente; VenezuelaFil: Ludwig, Sandra. Universidade Federal de Minas Gerais; BrasilFil: Pastorino, Roberto Santiago Guido. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Oficina de Coordinaci√≥n Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Oficina de Coordinaci√≥n Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Salvador, Rodrigo B.. Museum of New Zealand Te Papa Tongarewa,; Nueva Zelanda. The Artic University of Norway; NoruegaFil: Spotorno, Paula. Universidade Federal do Rio Grande; BrasilFil: Thiengo, Silvana. Fundaci√≥n Oswaldo Cruz; BrasilFil: Vidigal, Teofania Heloisa Dutra Amorim. Universidade Federal de Minas Gerais; BrasilFil: Darrigran, Gustavo Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Divisi√≥n de Zoolog√≠a Invertebrados; Argentina. Consejo Nacional de Investigaciones Cient√≠ficas y T√©cnicas. Centro Cient√≠fico Tecnol√≥gico Conicet - La Plata; Argentin

    Notas sobre el conocimiento limnológico de los gasterópodos paranenses y sus relaciones tróficas. II Planorbidae, con aspectos distribucionales y sanitarios

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    The present remarks on the family Planorbidae constitute a further work o f a series of contributions tending to fumish an integrated overview of the Paraná river’s malacologic fauna, the knowledge of which is most limited, particularly conceming thetaxonomic, biological and limnological aspects. To this effect, the aim of this work is, as well, to give an idea of its energy transfer to fishes and of its importance. This is best observed in the planorbids of the genus Biomphalaria, not particularly because of the importance of such energy contribution, but due to the preying capacity, consumption pressure, and consequent population control performed by certain fishes on these gastropods, some of which species are vectors of schistosomiasis. The fact becomes especially relevant when a sustained advance of this parasitosis towards Argentinianwaters is being noticed; for this reason, thorough investigations of this problem are suggested so as to prevent (or at least reduce) this serious threat which has to be realistically assumed..The present remarks on the family Planorbidae constitute a further work o f a series of contributions tending to fumish an integrated overview of the Paraná river’s malacologic fauna, the knowledge of which is most limited, particularly conceming thetaxonomic, biological and limnological aspects. To this effect, the aim of this work is, as well, to give an idea of its energy transfer to fishes and of its importance. This is best observed in the planorbids of the genus Biomphalaria, not particularly because of the importance of such energy contribution, but due to the preying capacity, consumption pressure, and consequent population control performed by certain fishes on these gastropods, some of which species are vectors of schistosomiasis. The fact becomes especially relevant when a sustained advance of this parasitosis towards Argentinianwaters is being noticed; for this reason, thorough investigations of this problem are suggested so as to prevent (or at least reduce) this serious threat which has to be realistically assumed
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