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The gastropod Pseudosuccinea columella participates in the dissemination of Fasciola hepatica in the environment, acting as the main intermediate host of this parasite in Brazil. The present study sought to elucidate the possible pathogenic effects of the entomopathogenic nematode (EPN) Heterorhabditis bacteriophora on P. columella, by evaluating the influence of infection on alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as well as the concentrations of total protein, uric acid, and urea in the snail's hemolymph. For this, the snails were exposed to EPNs for 24 and 48 h, and for each exposure time, 20 snails were dissected after 7, 14 and 21 days for hemolymph collection. The primary findings suggest a significant proteolysis alongside elevated levels of uric acid and urea in P. columella infected individuals. These findings reveal that H. bacteriophora HP88 infection induced serious changes in the snail's metabolism, triggering important deleterious effects.

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Worldwide, the tomato russet mite (TRM), Aculops lycopersici (Eriophyidae), is a key pest on cultivated tomato in addition to infesting other cultivated and wild Solanaceae; however, basic information on TRM supporting effective control strategies is still lacking, mainly regarding its taxonomic status and genetic diversity and structure. As A. lycopersici is reported on different species and genera of host plants, populations associated with different host plants may constitute specialized cryptic species, as shown for other eriophyids previously considered generalists. The main aims of this study were to (i) confirm the TRM taxonomic unity of populations from different host plants and localities as well as the species' oligophagy, and (ii) to advance the understanding of TRM host relationship and invasion history. For this purpose, we evaluated the genetic variability and structure of populations from different host plants along crucial areas of occurrence, including the area of potential origin, based on DNA sequences of mitochondrial (cytochrome c oxidase subunit I) and nuclear (internal transcribed spacer, D2 28S) genomic regions. Specimens from South America (Brazil) and Europe (France, Italy, Poland, The Netherlands) were collected from tomato and other solanaceous species from the genera Solanum and Physalis. Final TRM datasets were composed of 101, 82 and 50 sequences from the COI (672 bp), ITS (553 bp) and D2 (605 bp) regions, respectively. Distributions and frequencies of haplotypes (COI) and genotypes (D2 and ITS1) were inferred; pairwise genetic distance comparisons, and phylogenetic analysis were performed, including Bayesian Inference (BI) combined analysis. Our results showed that genetic divergences for mitochondrial and nuclear genomic regions from TRM associated with different host plants were lower than those observed in other eriophyid taxa, confirming conspecificity of TRM populations and oligophagy of this eriophyid mite. Four haplotypes (cH) were identified from the COI sequences with cH1 being the most frequent, representing 90% of all sequences occurring in all host plants studied (Brazil, France, The Netherlands); the other haplotypes were present exclusively in Brazilian populations. Six variants (I) were identified from the ITS sequences: I-1 was the most frequent (76.5% of all sequences), spread in all countries and associated with all host plants, except S. nigrum. Just one D2 sequence variant was found in all studied countries. The genetic homogeneity among populations highlights the occurrence of a highly invasive and oligophagous haplotype. These results failed to corroborate the hypothesis that differential symptomatology or damage intensity among tomato varieties and solanaceous host plants could be due to the genetic diversity of the associated mite populations. The genetic evidence, along with the history of spread of cultivated tomato, corroborates the hypothesis of a South American origin of TRM.

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Haemosporidian parasites can cause pathogenic infections, leading to death or a reduction in the physical and reproductive abilities of the host. Several studies have identified haemosporidian infections in neotropical bird communities, but few have been conducted in populations, relating the infection to the biological attributes of the species. To determine haemosporidian prevalence in a population of Antilophia galeata and to assess factors that may be associated with parasitaemia, we analysed blood smears of 62 individuals from a Cerrado forest fragment. For each individual, the body mass, length of tarsus, sex, presence/absence of brood patch and feather moult were recorded. In total, 33 (53.2%) individuals were infected with haemosporidian parasites, 32 (51.6%) were infected with Plasmodium spp. and one (1.61%) was infected with Haemoproteus sp. Parasitaemia was not related to seasons, sex, reproduction, moulting or body condition but correlated positively with total leucocyte count, suggesting that individuals may be effective in infection control. This population may be tolerant to haemosporidian parasites because, despite the high prevalence, parasitaemia was low and constant; this is a potentially chronic infection that showed no adverse effects on the parameters analysed in this population.

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The Amazon region may present a high diversity of endoparasites with a high degree of endemism. In this sense, this study describes the endoparasite fauna in freshwater fish from the Upper Juruá, in the Western Amazon. The study was carried out around the municipalities of Cruzeiro do Sul, state of Acre, and Guajará, state of Amazonas, Brazil. Fish were caught between periods of droughts and floods, using passive and active sampling methods. In the laboratory, specimens were biometrically analysed and necropsied. As a result, a total of 23,740 endoparasites were recorded, belonging to 62 species, with 91 new host reports and 91 new occurrences for the Western Amazon. Nematoda and Digenea were the most diverse and abundant groups, and the increase in host fish richness and diversity influenced the diversity and richness of endoparasites in the environments. In this sense, the present study expands the number of new reports, and contributes data on the distribution and richness of endoparasites for South America.

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RESUMEN La Transición Epitelio-Mesénquima (EMT) es un proceso de diferenciación altamente conservado en vertebrados. Este ocurre en células epiteliales con la activación progresiva de la pérdida de la polaridad, la adquisición de motilidad individual y la capacidad invasiva a otros tejidos. La EMT es un proceso normal durante el desarrollo; no obstante, en condiciones patológicas está relacionada con la inducción de metástasis, lo cual representa una vía alterna al desarrollo de procesos oncogénicos tempranos. Aunque la EMT es activada principalmente por factores de crecimiento, también se puede desencadenar por infecciones de patógenos intracelulares mediante la activación de rutas moleculares inductoras de este proceso. Por lo tanto, una infección bacteriana o viral pueda generar predisposición al desarrollo de tumores. Nuestro interés está enfocado principalmente en caracterizar la relación virus-hospedero, y en el caso de los virus, varios ya se han descrito como inductores de la EMT. En este artículo de revisión se describen el fenómeno de la plasticidad celular y la ocurrencia detallada del proceso de EMT, los patógenos virales reportados como inductores, los mecanismos moleculares usados para ello y las vías de regulación mediante miRNAs. Por último, se discute cómo esta relación virus-hospedero puede explicar la patogénesis de la enfermedad causada por Dengue virus, favoreciendo la identificación de blancos moleculares para terapia, estrategia conocida como Antivirales dirigidos a blancos celulares o HTA (Host-targeting antivirals).

ABSTRACT Epithelial-to-Mesenchymal Transition (EMT) is a highly conserved dedifferentiation process in vertebrates. This process occurs in epithelial cells activating progressive loss of cell polarity, acquisition of individual motility and invasive capacity to other tissues. EMT is a normal process during development process, however, in pathological conditions is related to the induction of metastasis, which represents an alternative path to the development of early oncogenic processes. Although, EMT is mainly activated by growth factors, it can also be triggered by intracellular-pathogen-infections by activating molecular pathways that induce this process. Therefore, a bacterial or viral infection may generate predisposition to the development of tumors. Our interest is mainly focused on characterizing the host-virus relationship, and in the case of viruses, several have already been described as EMT inductors. In this review, phenomenon of cellular plasticity, detailed occurrence of the EMT, viral pathogens reported as inducers, the molecular mechanisms, and the regulatory pathways through miRNAs are described. Finally, we discuss how this host-virus relationship may explain the pathogenesis of the disease caused by Dengue virus, favoring the identification of molecular targets for therapy, a strategy known as Host-Targeting Antivirals (HTA).

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A taxonomic checklist of Chalcidoidea (Hymenoptera) associated with Bruchinae (Coleoptera: Chrysomelidae) is presented. A total of 139 species of Chalcidoidea or unidentified species to genus are reported as primary parasitoids. The valid name, primary host(s) (animal and plant taxa), distribution and references for each species are listed.

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Detritivoria and parasitism are dietary habits already registered for the phorids of the genus Megaselia Rondani. The results of this study confirm the parasitic habit of Megaselia larvae. This is the first Pachylia ficus (Linnaeus, 1758) (Lepidoptera: Sphingidae) adult record as a host of Megaselia scalaris (Loew, 1866) and Megaselia sp. (Diptera: Phoridae).(AU)

Detritivoria e parasitismo são hábitos alimentares já registrados para os forídeos do gênero Megaselia Rondani. Os resultados do presente estudo confirmam o hábito parasitário das larvas de Megaselia. Este é o primeiro registro de adulto de Pachylia ficus (Linnaeus, 1758) (Lepidoptera: Sphingidae) como hospedeiro de Megaselia scalaris (Loew, 1866) e Megaselia sp. (Diptera: Phoridae).(AU)

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Detritivoria and parasitism are dietary habits already registered for the phorids of the genus Megaselia Rondani. The results of this study confirm the parasitic habit of Megaselia larvae. This is the first Pachylia ficus (Linnaeus, 1758) (Lepidoptera: Sphingidae) adult record as a host of Megaselia scalaris (Loew, 1866) and Megaselia sp. (Diptera: Phoridae).(AU)

Detritivoria e parasitismo são hábitos alimentares já registrados para os forídeos do gênero Megaselia Rondani. Os resultados do presente estudo confirmam o hábito parasitário das larvas de Megaselia. Este é o primeiro registro de adulto de Pachylia ficus (Linnaeus, 1758) (Lepidoptera: Sphingidae) como hospedeiro de Megaselia scalaris (Loew, 1866) e Megaselia sp. (Diptera: Phoridae).(AU)

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This is the first complete assessment of the ectoparasite fauna on phyllostomid bats in a shaded coffee plantation in Mexico. The study was carried out at Finca San Carlos, in the municipality of Tapachula, southeastern Chiapas, Mexico. The bats were captured over three consecutive nights every month, from December 2005 to November 2006, using four mist nets. We captured 192 phyllostomid bats, representing 18 species, upon which 1,971 ectoparasites, belonging to 11 families and 65 species, were found. We found that 160 of the 192 captured bats were hosts to ectoparasites, giving an infestation prevalence of 83.3%. Of the 65 ectoparasitic species, 14 were classified as monoxenous and 17 as stenoxenous. More ectoparasites were recorded in the dry season (n = 1,439) than the wet season (n = 532), and we recorded some families of ectoparasite on particular areas of the bat body. An ordination of bat species, based on their ectoparasitic species community structure, formed groups at the subfamily level or lower taxonomic categories. We suggest that the close ectoparasite-host relationships could be examined as an additional tool to elucidate the taxonomic relationships between the hosts.

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For over a century, viruses have been known as the most abundant and diverse group of organisms on Earth, forming a virosphere. Based on extensive meta-analyses, we present, for the first time, a wide and complete overview of virus-host network, covering all known viral species. Our data indicate that most of known viral species, regardless of their genomic category, have an intriguingly narrow host range, infecting only 1 or 2 host species. Our data also show that the known virosphere has expanded based on viruses of human interest, related to economical, medical or biotechnological activities. In addition, we provide an overview of the distribution of viruses on different environments on Earth, based on meta-analyses of available metaviromic data, showing the contrasting ubiquity of head-tailed phages against the specificity of some viral groups in certain environments. Finally, we uncovered all human viral species, exploring their diversity and the most affected organic systems. The virus-host network presented here shows an anthropocentric view of the virology. It is therefore clear that a huge effort and change in perspective is necessary to see more than the tip of the iceberg when it comes to virology.

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ABSTRACT It is not unusual to find epiphytic bromeliads in mangroves, but most studies on mangrove vegetation do not record their presence. This study aimed to evaluate the diversity and distribution of epiphytic bromeliads in a subtropical mangrove. The richness, abundance and life form (atmospheric and tank) of bromeliads were recorded and compared among host tree species and waterline proximity. The effects of diameter and height of host trees on the abundance of bromeliads were also assessed. The mangrove was composed of Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle. We recorded seven bromeliad species of the genera Tillandsia and Vriesea. The waterline proximity did not affect the abundance or diversity of bromeliads, but atmospheric forms were predominant near the waterline, whereas tank bromeliads were more frequent in the interior of the mangrove. The three mangrove species hosted bromeliads, but L. racemosa was the preferred host. The species composition showed that the distribution of bromeliads is more related to the host species than to the distance from the waterline. Bromeliad abundance increased with tree size. Bromeliads can be biological indicators of ecosystem health; therefore, inventories and host tree preferences are necessary knowledge for an adequate management of sensitive ecosystems as mangroves.

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The unionid Anodontites trapesilais (Lamarck, 1819) like most freshwater mussels is a parasite of fish. So it is trivial to assume that the availability of hosts is an important factor for the maintenance of unionoid populations. What seems obvious is not always so easy to demonstrate. This study proposes to investigate the effects of abiotic and biotic variables related to the incubation of larvae in A. trapesialis. For this, we estimate different biological indexes and try to capture the dimensionality of the fish, along with the temporal variation of environmental variables. From the application of a CCA, it was demonstrated that there was a synchronicity among the factors and variables proposed here, and we infer that the flood pulse acts as a synergistic factor in this process.

O bivalve Anodontites trapesilais (Lamarck, 1819), como a maioria dos mexilhões de água doce, é parasita de peixes. Então, seria trivial supor que a disponibilidade de hospedeiros é um fator importante para a manutenção das populações dos unionoideos. Porém, o que parece óbvio nem sempre é tão simples de ser demonstrado. Este estudo se propõe a investigar os efeitos de variáveis abióticas e bióticas relacionadas com a incubação de larvas de A. trapesialis. Para tanto, nós estimamos diferentes Índices Biológicos e tentamos capturar a dimensionalidade da comunidade de peixes juntamente com a variação temporal das variáveis ambientais. A partir da aplicação de uma CCA, demonstramos que há uma sincronicidade entre os fatores e as variáveis aqui propostas, e inferimos que o pulso de inundação atua como fator sinergético desse processo.

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El parásito Trypanosoma rangeli, protozoo de la familia Trypanosomatidae, se considera no patógeno para el hospedero vertebrado; sin embargo, en las poblaciones del insecto vector produce efectos patogénicos que desencadenan en la muerte de los triatomíneos infectados. Este hemoflagelado comparte con Trypanosoma cruzi, agente etiológico de la enfermedad de Chagas, características biológicas e inmunoquímicas tales como la distribución geográfica, los reservorios, vectores, hospederos vertebrados y determinantes antigénicos. Por esta razón es una fuente de confusión en el diagnóstico de la enfermedad de Chagas y debe ser considerado como un parásito de importancia médica. A pesar de lo anteriormente mencionado, el conocimiento sobre T. rangeli es muy poco y fragmentado en sus aspectos bioquímicos, inmunológicos y moleculares. En este artículo se presenta una revisión de características biológicas de este parásito con el fi n de enfatizar y estimular la investigación dándole la importancia que se merece.

Trypanosoma rangeli is a protozoan parasite belonging to the Trypanosomatidae family and, generally, is not considered a pathogenic for a vertebrate host. However, T. rangeli produces pathogenic effects for insect vector populations that sometimes causes the death of infected triatomideae. This hemoflagellate shares with Trypanosoma cruzi, the etiological agent of Chagas´ disease, immunochemical and biological characteristics such as geographical distribution, animal reservoirs, vectors, vertebrate hosts and antigenic determinants. This is one of the reasons for a great deal of confusion, when we diagnose Chagas´ disease. Therefore, we should consider this parasite as an important one for medical research. However, despite of the above, we accept the fact that our knowledge about T. rangeli is quite limited, basically regarding its biochemical, immunological and molecular characteristics. In this article we review several biological characteristics of T. rangeli, in order to motivate more extensive research on this important parasite as a medical tool.

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