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Sample records for abundans platyhelminthes tricladida

  1. Predatory behavior of the land flatworm Notogynaphallia abundans (Platyhelminthes: Tricladida

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    Maria E. T. Prasniski

    2009-12-01

    Full Text Available Land flatworms are carnivorous, mainly predators. However, knowledge on their predatory behavior and prey preference is very scarce. This paucity of data is a limiting factor in the study of their biology and organismal ecology, resulting in a very difficult task to breed them in the laboratory for prolonged periods if prey preference and predation frequency are unknown. We investigated the predatory behavior of Notogynaphallia abundans (Graff, 1899, Geoplaninae, based on laboratory experiments. In order to determine its predatory choices, we offered mollusks, earthworms, arthropods, and other land flatworms. Only land isopods were accepted, with an average consumption of 3.4 individuals per week. Linear regression showed a positive relationship between the number of consumed isopods and the increase/decrease in body mass. Consumption resulting in an increase in body mass was ca. four isopods per week. Predatory behavior, with a mean time-span of 28 min 45 s ± 15 min 47 s, includes encounter and capture of prey, immobilization, handling and feeding. Variation in the duration of this activity in N. abundans is clearly due to variations in the time necessary for transferring the prey from either the anterior or posterior thirds of the body to the mouth, as well as for external digestion and ingestion. In order to capture very active and fast-moving animals such as land isopods, N. abundans employs various strategies, using either the anterior or the posterior body regions to press the prey against the ground or against its own body, thus allowing it to deal with various responses by the prey, and thereby maximizing predatory success. Similar to other flatworms, both physical holding and entrapment in a mucous secretion are of fundamental importance for prey-immobilization. The different strategies employed by land flatworms in their predatory behavior are discussed, and behavioral plasticity in the capture and immobilization of prey in different

  2. Predatory behavior of the land flatworm Notogynaphallia abundans (Platyhelminthes: Tricladida)

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    Maria E. T. Prasniski; Ana M. Leal-Zanchet

    2009-01-01

    Land flatworms are carnivorous, mainly predators. However, knowledge on their predatory behavior and prey preference is very scarce. This paucity of data is a limiting factor in the study of their biology and organismal ecology, resulting in a very difficult task to breed them in the laboratory for prolonged periods if prey preference and predation frequency are unknown. We investigated the predatory behavior of Notogynaphallia abundans (Graff, 1899), Geoplaninae, based on laboratory experime...

  3. Planarian (Platyhelminthes, Tricladida Diversity and Molecular Markers: A New View of an Old Group

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    Marta Álvarez-Presas

    2014-04-01

    Full Text Available Planarians are a group of free-living platyhelminths (triclads best-known largely due to long-standing regeneration and pattern formation research. However, the group’s diversity and evolutionary history has been mostly overlooked. A few taxonomists have focused on certain groups, resulting in the description of many species and the establishment of higher-level groups within the Tricladida. However, the scarcity of morphological features precludes inference of phylogenetic relationships among these taxa. The incorporation of molecular markers to study their diversity and phylogenetic relationships has facilitated disentangling many conundrums related to planarians and even allowed their use as phylogeographic model organisms. Here, we present some case examples ranging from delimiting species in an integrative style, and barcoding them, to analysing their evolutionary history on a lower scale to infer processes affecting biodiversity origin, or on a higher scale to understand the genus level or even higher relationships. In many cases, these studies have allowed proposing better classifications and resulted in taxonomical changes. We also explain shortcomings resulting in a lack of resolution or power to apply the most up-to-date data analyses. Next-generation sequencing methodologies may help improve this situation and accelerate their use as model organisms.

  4. Nova espécie de Geoplana Stimpson (Platyhelminthes, Tricladida, Terricola do sul do Brasil A new species of Geoplana Stimpson (Platyhelminthes, Tricladida, Terricola from South Brasil

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    Vanessa dos A. Baptista

    2005-12-01

    Full Text Available Descreve-se uma nova espécie de Geoplana Stimpson, 1857 ocorrente na Floresta Nacional de São Francisco de Paula, Rio Grande do Sul, Brasil. Geoplana rubidolineata sp. nov. possui padrão de coloração característico, além de uma combinação de caracteres da morfologia interna, que a diferencia das demais espécies que apresentam epitélio com aparência estratificada revestindo o átrio feminino.A new species of Geoplana Stimpson, 1857, registered for the National Forest of São Francisco de Paula, Rio Grande do Sul, Brasil, is described. Geoplana rubidolineata sp. nov. has a characteristic colour pattern, as well as a combination of characters of the internal morphology, which differentiate it from other species presenting a lining in the female atrium with multilayered aspect.

  5. Ecology, karyology, and anatomy of the planarian Pentacoelum hispaniense Sluys, 1989 (Platyhelminthes, Tricladida

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    Ferrer, X.

    2008-06-01

    Full Text Available On the basis of recently discovered new populations of the triclad flatworm Pentacoelum hispaniense new data are detailed on the ecology, reproduction, karyology, and anatomy of the species, including the first description of the external appearance of living specimens. Living animals show three refringent patches on the dorsal surface of which the nature and function remain unknown. The diploid chromosome complement consists of 14 chromosomes. The species appears to be restricted to relatively warm, lowland bodies of water, where it may be found in heterogeneous habitats. The species reproduces only sexually through the production of cocoons. This study presents the first record of a digenean flatworm parasitizing a marine triclad in the form of a metacercaria.Basándonos en las nuevas poblaciones descubiertas del tríclado Pentacoelum hispaniense aportamos nuevos datos ecológicos, reproductivos, cariológicos y anatómicos de la especie, incluyendo la primera descripción de la anatomía externa. Estos animales presentan tres manchas dorsales refringentes de naturaleza y función desconocidas. El complemento cromosómico diploide consta de 14 cromosomas. La especie parece restringida a masas de agua relativamente cálidas de tierras bajas, donde puede ser encontrada en hábitats heterogéneos. Su reproducción es exclusivamente sexual mediante la producción de capullos. El presente estudio recoge la primera cita de un digenio parasitando un tríclado del grupo de las marícolas, en el estadio de metacercaria.

  6. Freshwater planarians from artesian springs in Queensland, Australia (Platyhelminthes, Tricladida, Paludicola)

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    Sluys, R.; Grant, L.J.; Blair, D.

    2007-01-01

    Two new species of triclad flatworm are described from artesian springs in Queensland, Australia, viz. Dugesia artesiana Sluys and Grant, sp. nov. and Weissius capaciductus Sluys, gen. et sp. nov. Some historical biogeographic scenarios are discussed that may explain the occurrence of the new specie

  7. Two new species of freshwater flatworms (Platyhelminthes: Tricladida: Continenticola) from South American caves.

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    Souza, Stella; Morais, Ana Laura; Bichuette, Maria Elina; Leal-Zanchet, Ana

    2016-01-01

    The diversity of freshwater triclads in the Neotropical region is considered to be low, but extensive areas of South America remain almost unexplored. Herein we describe two cave-dwelling, new species of Girardia, one from a transition zone of the Cerrado and Caatinga phytophysiognomies and the other from the Cerrado phytophysiognomy. The species from the Cerrado-Caatinga transition is a troglobite, eyeless and whitish; the species from the Cerrado area is possibly a troglophile, since it shows heavily pigmented body and eyes. Each species is easily recognized by a unique combination of features in its external morphology and copulatory apparatus. The two new species of Girardia show a restricted distribution, even the troglophile, and occur in caves without legal protection. Therefore, they must be considered as vulnerable organisms in a conservation context. PMID:27394369

  8. A new and aberrant species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae from Madagascar

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    Giacinta Stocchino

    2014-07-01

    Full Text Available In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia.

  9. First report of the land planarian Diversibipalium multilineatum (Makino & Shirasawa, 1983) (Platyhelminthes, Tricladida, Continenticola) in Europe.

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    Mazza, Giuseppe; Menchetti, Mattia; Sluys, Ronald; Solà, Eduard; Riutort, Marta; Tricarico, Elena; Justine, Jean-Lou; Cavigioli, Luca; Mori, Emiliano

    2016-01-01

    Introduction of alien species may significantly affect soil ecosystems, through predation or disruption of components of native ecosystems (Winsor et al. 2004; Álvarez-Presas et al. 2014; Justine et al. 2014). Land planarians have been reported as alien species in soils throughout the world and, among those, some species are considered to be successful invaders, e.g. Platydemus manokwari de Beauchamp, 1963, Arthurdendyus triangulatus (Dendy, 1894), Bipalium adventitium Hyman, 1943, Bipalium kewense Moseley, 1878 and Dolichoplana striata Moseley, 1877 (Winsor et al. 2004; Álvarez-Presas et al. 2014; Justine et al. 2014, 2015). Soil moisture status seems to be an important element for their successful invasion (Fraser & Boag 1998). In Europe at least 18 species of alien land planarians have been recorded since now and some of them are considered as invasive ones, e.g. P. manokwari (cf. Justine et al. 2014). Although the alien land planarian B. kewense has been reported to occur in many greenhouses in Italy (Bello et al. 1995), no data are available on its establishment and/or impact on natural environments. On 28th September 2014, 20 specimens (~1 individual/m2) of the land planarian Diversibipalium multilineatum (Makino & Shirasawa, 1983) (Fig. 1), native to Japan, were collected under pots, branches and plastic materials in a private garden located in the center of Bologna (Emilia Romagna, Central Italy), near the urban park Giardini Margherita (44°29' N, 11°21' E; WGS84). Thirty plant species (both indigenous and alien), mainly cultivated as bonsai (e.g. Lagerstroemia indica L., Juniperus procumbens (Siebold ex Endl.) Miquel), were present in this shady, wet garden (25 m2). Between March 2014 and June 2015, 70 more specimens of D. multilineatum were collected at the same site, mainly at dusk and dawn after rain. Reproduction by fission and regeneration processes were observed in several of those specimens, which were kept for some time in captivity. A specimen of D. multilineatum was also collected in a garden in Léguevin (Haute-Garonne, France), which will be described in a forthcoming paper by Justine et al. (in prep.) (see also Kawakatsu et al. 2014). Specimens without a genital pore were initially ascribed to D. multilineatum on the basis of their external appearance: the dorsal surface was brownish yellow and presented five longitudinal stripes at the head plate and the neck, showing the typical appearance of the species. The middorsal stripe was widened at its anterior end, on the head plate, and at the pharynx level. The ventral pattern of the animals at the pharyngeal region was also characteristic, with the middorsal stripe widened at this level. The Italian Diversibipalium specimens used for the molecular analysis were fixed and preserved in absolute ethanol. Fragments of the mitochondrial gene COI and 28S ribosomal RNA nuclear gene (GenBank Acc. Numbers KU245358 and KU245357, respectively) were obtained using the procedure and COI primers described in Álvarez-Presas et al. (2008) and Solà et al. (2013). The French specimen's COI (Specimen MNHN JL177, GenBank Acc. Number KT922162) was obtained as described in Justine et al. (2015). 28S sequences of 14 Bipaliinae specimens and four Microplana species (outgroup) retrieved from GenBank were included in the phylogenetic analyses (Fig. 2). Sequence alignment was obtained by using the online software MAFFT version 7 (Katoh & Standley 2013), while ambiguously aligned positions were removed using the program Gblocks (Talavera & Castresana 2007) with default settings, excepting the minimum number of sequences for a flank position at the minimum value (set at 10) and with half of the allowed gap positions. The final alignment had a length of 1589 bp. We used two phylogenetic inference approaches: maximum likelihood (ML), using the RaxML 8.2.3 software (Stamatakis 2014), and Bayesian inferences (BI), using MrBayes 3.2.4 (Ronquist et al. 2012). The evolutionary model used, GTR+I+G, was estimated t

  10. First report of the land planarian Diversibipalium multilineatum (Makino & Shirasawa, 1983) (Platyhelminthes, Tricladida, Continenticola) in Europe.

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    Mazza, Giuseppe; Menchetti, Mattia; Sluys, Ronald; Solà, Eduard; Riutort, Marta; Tricarico, Elena; Justine, Jean-Lou; Cavigioli, Luca; Mori, Emiliano

    2016-01-01

    Introduction of alien species may significantly affect soil ecosystems, through predation or disruption of components of native ecosystems (Winsor et al. 2004; Álvarez-Presas et al. 2014; Justine et al. 2014). Land planarians have been reported as alien species in soils throughout the world and, among those, some species are considered to be successful invaders, e.g. Platydemus manokwari de Beauchamp, 1963, Arthurdendyus triangulatus (Dendy, 1894), Bipalium adventitium Hyman, 1943, Bipalium kewense Moseley, 1878 and Dolichoplana striata Moseley, 1877 (Winsor et al. 2004; Álvarez-Presas et al. 2014; Justine et al. 2014, 2015). Soil moisture status seems to be an important element for their successful invasion (Fraser & Boag 1998). In Europe at least 18 species of alien land planarians have been recorded since now and some of them are considered as invasive ones, e.g. P. manokwari (cf. Justine et al. 2014). Although the alien land planarian B. kewense has been reported to occur in many greenhouses in Italy (Bello et al. 1995), no data are available on its establishment and/or impact on natural environments. On 28th September 2014, 20 specimens (~1 individual/m2) of the land planarian Diversibipalium multilineatum (Makino & Shirasawa, 1983) (Fig. 1), native to Japan, were collected under pots, branches and plastic materials in a private garden located in the center of Bologna (Emilia Romagna, Central Italy), near the urban park Giardini Margherita (44°29' N, 11°21' E; WGS84). Thirty plant species (both indigenous and alien), mainly cultivated as bonsai (e.g. Lagerstroemia indica L., Juniperus procumbens (Siebold ex Endl.) Miquel), were present in this shady, wet garden (25 m2). Between March 2014 and June 2015, 70 more specimens of D. multilineatum were collected at the same site, mainly at dusk and dawn after rain. Reproduction by fission and regeneration processes were observed in several of those specimens, which were kept for some time in captivity. A specimen of D. multilineatum was also collected in a garden in Léguevin (Haute-Garonne, France), which will be described in a forthcoming paper by Justine et al. (in prep.) (see also Kawakatsu et al. 2014). Specimens without a genital pore were initially ascribed to D. multilineatum on the basis of their external appearance: the dorsal surface was brownish yellow and presented five longitudinal stripes at the head plate and the neck, showing the typical appearance of the species. The middorsal stripe was widened at its anterior end, on the head plate, and at the pharynx level. The ventral pattern of the animals at the pharyngeal region was also characteristic, with the middorsal stripe widened at this level. The Italian Diversibipalium specimens used for the molecular analysis were fixed and preserved in absolute ethanol. Fragments of the mitochondrial gene COI and 28S ribosomal RNA nuclear gene (GenBank Acc. Numbers KU245358 and KU245357, respectively) were obtained using the procedure and COI primers described in Álvarez-Presas et al. (2008) and Solà et al. (2013). The French specimen's COI (Specimen MNHN JL177, GenBank Acc. Number KT922162) was obtained as described in Justine et al. (2015). 28S sequences of 14 Bipaliinae specimens and four Microplana species (outgroup) retrieved from GenBank were included in the phylogenetic analyses (Fig. 2). Sequence alignment was obtained by using the online software MAFFT version 7 (Katoh & Standley 2013), while ambiguously aligned positions were removed using the program Gblocks (Talavera & Castresana 2007) with default settings, excepting the minimum number of sequences for a flank position at the minimum value (set at 10) and with half of the allowed gap positions. The final alignment had a length of 1589 bp. We used two phylogenetic inference approaches: maximum likelihood (ML), using the RaxML 8.2.3 software (Stamatakis 2014), and Bayesian inferences (BI), using MrBayes 3.2.4 (Ronquist et al. 2012). The evolutionary model used, GTR+I+G, was estimated to be the best with the software jModeltest 2.1.7 (Darriba et al. 2012

  11. Efficacy of Chlorella pyrenoidosa and Scenedesmus abundans for Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water).

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    Abinandan, S; Bhattacharya, Ribhu; Shanthakumar, S

    2015-01-01

    Microalgae are product of sustainable development owing to its ability to treat variety of wastewater effluents and thus produced biomass can serve as value added product for various commercial applications. This paper deals with the cultivation of microalgae species namely Chlorella pyrenoidosa and Scenedesmus abundans in rice mill effluent (i.e., paddy soaked water) for nutrient removal. In order to investigate the nutrient removal capability, microalgae are subjected to cultivation in both raw and autoclaved samples. The maximum phosphate removal by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 98.3% and 97.6%, respectively, whereas, the removal of ammoniacal nitrogen by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 92% and 90.3%, respectively. The growth (measured in terms of chlorophyll content) of Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 3.88 mg/l and 5.55 mg/l, respectively. The results indicate the suitability of microalgae cultivation in rice mill effluent treatment for nutrient removal.

  12. Fluvial basin history in the northeastern Mediterranean region underlies dispersal and speciation patterns in the genus Dugesia (Platyhelminthes, Tricladida, Dugesiidae).

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    Solà, Eduard; Sluys, Ronald; Gritzalis, Konstantinos; Riutort, Marta

    2013-03-01

    In this study we analyzed the phylogenetic relationships of eastern Mediterranean freshwater planarians of the genus Dugesia, estimated divergence times for the various clades, and correlated their phylogeographic patterns with geological and paleoclimatic events, in order to discover which evolutionary processes have shaped the present-day distribution of these animals. Specimens were collected from freshwater courses and lakes in continental and insular Greece. Genetic divergences and phylogenetic relationships were inferred by using the mitochondrial gene subunit I of cytochrome oxidase (COI) and the nuclear ribosomal internal transcribed spacer-1 (ITS-1) from 74 newly collected individuals from Greece. Divergence time estimates were obtained under a Bayesian framework, using the COI sequences. Two alternative geological dates for the isolation of Crete from the mainland were tested as calibration points. A clear phylogeographic pattern was present for Dugesia lineages in the Eastern Mediterranean. Morphological data, combined with information on genetic divergences, revealed that eight out of the nine known species were represented in the samples, while additional new, and still undescribed species were detected. Divergence time analyses suggested that Dugesia species became isolated in Crete after the first geological isolation of the island, and that their present distribution in the Eastern Mediterranean has been shaped mainly by vicariant events but also by dispersal. During the Messinian salinity crisis these freshwater planarians apparently were not able to cross the sea barrier between Crete and the mainland, while they probably did disperse between islands in the Aegean Sea. Their dependence on freshwater to survive suggests the presence of contiguous freshwater bodies in those regions. Our results also suggest a major extinction of freshwater planarians on the Peloponnese at the end of the Pliocene, while about 2Mya ago, when the current Mediterranean climate was established, these Peloponnese populations probably began to disperse again. At the end of the Pliocene or during the Pleistocene, mainland populations of Dugesia colonized the western coast, including the Ionian Islands, which were then part of the continent. PMID:23182762

  13. Comparative analysis of cystatin superfamily in platyhelminths.

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    Guo, Aijiang

    2015-01-01

    The cystatin superfamily is comprised of cysteine proteinase inhibitors and encompasses at least 3 subfamilies: stefins, cystatins and kininogens. In this study, the platyhelminth cystatin superfamily was identified and grouped into stefin and cystatin subfamilies. The conserved domain of stefins (G, QxVxG) was observed in all members of platyhelminth stefins. The three characteristics of cystatins, the cystatin-like domain (G, QxVxG, PW), a signal peptide, and one or two conserved disulfide bonds, were observed in platyhelminths, with the exception of cestodes, which lacked the conserved disulfide bond. However, it is noteworthy that cestode cystatins had two tandem repeated domains, although the second tandem repeated domain did not contain a cystatin-like domain, which has not been previously reported. Tertiary structure analysis of Taenia solium cystatin, one of the cestode cystatins, demonstrated that the N-terminus of T. solium cystatin formed a five turn α-helix, a five stranded β-pleated sheet and a hydrophobic edge, similar to the structure of chicken cystatin. Although no conserved disulfide bond was found in T. solium cystatin, the models of T. solium cystatin and chicken cystatin corresponded at the site of the first disulfide bridge of the chicken cystatin. However, the two models were not similar regarding the location of the second disulfide bridge of chicken cystatin. These results showed that T. solium cystatin and chicken cystatin had similarities and differences, suggesting that the biochemistry of T. solium cystatin could be similar to chicken cystatin in its inhibitory function and that it may have further functional roles. The same results were obtained for other cestode cystatins. Phylogenetic analysis showed that cestode cystatins constituted an independent clade and implied that cestode cystatins should be considered to have formed a new clade during evolution.

  14. Comparative analysis of cystatin superfamily in platyhelminths.

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    Aijiang Guo

    Full Text Available The cystatin superfamily is comprised of cysteine proteinase inhibitors and encompasses at least 3 subfamilies: stefins, cystatins and kininogens. In this study, the platyhelminth cystatin superfamily was identified and grouped into stefin and cystatin subfamilies. The conserved domain of stefins (G, QxVxG was observed in all members of platyhelminth stefins. The three characteristics of cystatins, the cystatin-like domain (G, QxVxG, PW, a signal peptide, and one or two conserved disulfide bonds, were observed in platyhelminths, with the exception of cestodes, which lacked the conserved disulfide bond. However, it is noteworthy that cestode cystatins had two tandem repeated domains, although the second tandem repeated domain did not contain a cystatin-like domain, which has not been previously reported. Tertiary structure analysis of Taenia solium cystatin, one of the cestode cystatins, demonstrated that the N-terminus of T. solium cystatin formed a five turn α-helix, a five stranded β-pleated sheet and a hydrophobic edge, similar to the structure of chicken cystatin. Although no conserved disulfide bond was found in T. solium cystatin, the models of T. solium cystatin and chicken cystatin corresponded at the site of the first disulfide bridge of the chicken cystatin. However, the two models were not similar regarding the location of the second disulfide bridge of chicken cystatin. These results showed that T. solium cystatin and chicken cystatin had similarities and differences, suggesting that the biochemistry of T. solium cystatin could be similar to chicken cystatin in its inhibitory function and that it may have further functional roles. The same results were obtained for other cestode cystatins. Phylogenetic analysis showed that cestode cystatins constituted an independent clade and implied that cestode cystatins should be considered to have formed a new clade during evolution.

  15. Histological and histochemical characterization of secretory cells of the male copulatory organs of Girardia anderlani (Platyhelminthes: Tricladida: Paludicola Caracterização histológica e histoquímica das células secretoras dos órgãos do aparelho copulador masculino de Girardia anderlani (Platyhelminthes: Tricladida: Paludicola

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    Dioneia C. da Vara

    2008-06-01

    Full Text Available Glands of the reproductive system are important for taxonomical identification of flatworms. We studied the histology and histochemical characteristics of the glands of the male copulatory apparatus in Girardia anderlani (KAWAKATSU & HAUSER, 1983. Specimens were fixed in reproductive state, i. e. during and following copulation at four, eight, 12 and 16 hours intervals. Secretory cells were distinguished on the basis of secretion morphology and their staining properties, using trichrome methods and histochemical reactions. Twelve secretory cell types and five main types of secretions were identified in the male copulatory apparatus: glycoproteic with and without tryptophan; glycosaminoglycidic; neutral mucopolysaccharidic; and proteic. Compared to other Girardia species, more diverse types of secretory cells comprise the glands of the male reproductive system. Histophysiological comparative studies of species of Girardia, in a reproductive state, are necessary to characterize the various regions of the copulatory apparatus as well as to understand the physiology of reproduction.Considerando a importância das glândulas do sistema reprodutor para a caracterização taxonômica de planárias, o presente trabalho objetiva fornecer uma descrição detalhada da histologia e a primeira caracterização histoquímica das glândulas do aparelho copulador masculino de Girardia anderlani (KAWAKATSU & HAUSER, 1983. A análise foi realizada em espécimes fixados em período reprodutivo, i. e., durante e após a cópula (períodos de quatro, oito, 12 e 16 horas. As células secretoras foram diferenciadas com base na morfologia da secreção e em sua coloração com métodos tricrômicos e reações histoquímicas. Doze tipos de células secretoras e cinco tipos principais de secreção foram identificados no aparelho copulador masculino de G. anderlani: glicoprotéica com e sem triptofano, glicosaminoglicídica, mucopolissacarídica neutra e protéica. Em comparação com outras espécies de Girardia, verifica-se maior variedade de células secretoras constituindo as glândulas do aparelho reprodutor masculino de G. anderlani. Estudos histofisiológicos comparativos de espécies de Girardia, em período reprodutivo, são necessários para a devida caracterização das diversas regiões do aparelho copulador e compreensão da fisiologia da reprodução.

  16. Redescription of two land planarian species of Notogynaphallia Ogren & Kawakatsu (Platyhelminthes, Tricladida, Geoplaninae and confirmation of the heterogeneity of the genus Redescrição de duas espécies de Notogynaphallia Ogren & Kawakatsu (Platyhelminthes, Tricladida, Geoplaninae e confirmação da heterogeneidade do gênero

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    Fernando Carbayo

    2006-09-01

    Full Text Available Notogynaphallia caissara (E.M. Froehlich, 1955 and N. fita (Froehlich, 1959 are redescribed. Both species are included in the so-called group 2 of E.M. Froehlich & Leal-Zanchet (2003, in Notogynaphallia, and are provided with a cephalic retractor muscle derived from the ventral longitudinal subepidermic muscle layer. A muscle retractor does not exist in the type-species of the genus. This is strong evidence of the morphological heterogeneity within the genus, as E.M. Froehlich & Leal-Zanchet (2003 previously proposed mainly based on characters of the reproductive organs.Redescrevem-se N. caissara (E.M. Froehlich, 1955 e N. fita (Froehlich, 1959, reunidas no chamado grupo 2 de E.M. Froehlich & Leal-Zanchet (2003, dentro de Notogynaphallia. Ambas as espécies possuem um músculo retrator cefálico derivado da musculatura subepidérmica longitudinal ventral. A presença deste retrator nas duas espécies, mas não na espécie-tipo do gênero, é uma evidência consistente da heterogeneidade morfológica do gênero, como previamente sugerido por E.M. Froehlich & Leal-Zanchet (2003 com base em características dos órgãos reprodutores.

  17. Acoel flatworms are not platyhelminthes: evidence from phylogenomics.

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    Hervé Philippe

    Full Text Available Acoel flatworms are small marine worms traditionally considered to belong to the phylum Platyhelminthes. However, molecular phylogenetic analyses suggest that acoels are not members of Platyhelminthes, but are rather extant members of the earliest diverging Bilateria. This result has been called into question, under suspicions of a long branch attraction (LBA artefact. Here we re-examine this problem through a phylogenomic approach using 68 different protein-coding genes from the acoel Convoluta pulchra and 51 metazoan species belonging to 15 different phyla. We employ a mixture model, named CAT, previously found to overcome LBA artefacts where classical models fail. Our results unequivocally show that acoels are not part of the classically defined Platyhelminthes, making the latter polyphyletic. Moreover, they indicate a deuterostome affinity for acoels, potentially as a sister group to all deuterostomes, to Xenoturbellida, to Ambulacraria, or even to chordates. However, the weak support found for most deuterostome nodes, together with the very fast evolutionary rate of the acoel Convoluta pulchra, call for more data from slowly evolving acoels (or from its sister-group, the Nemertodermatida to solve this challenging phylogenetic problem.

  18. Integrative taxonomy of a new species of planarian from the Lake Ohrid basin, including an analysis of biogeographical patterns in freshwater triclads from the Ohrid region (Platyhelminthes, Tricladida, Dugesiidae)

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    Giacinta Stocchino; Ronald Sluys; Paolo Deri; Renata Manconi

    2013-01-01

    Abstract A new species of the genus Dugesia is described from the Lake Ohrid region in the western part of the Balkan Peninsula, forming the first fully documented species description for this genus in the Ohrid area. The morphological species delimitation is supported by complementary molecular, karyological, and cytogenetic data available from the literature. Therefore, species delineation is based on a truly integrative approach. Further, a short account on the degree of freshwater planari...

  19. Integrative taxonomy of a new species of planarian from the Lake Ohrid basin, including an analysis of biogeographical patterns in freshwater triclads from the Ohrid region (Platyhelminthes, Tricladida, Dugesiidae).

    Science.gov (United States)

    Stocchino, Giacinta Angela; Sluys, Ronald; Deri, Paolo; Manconi, Renata

    2013-01-01

    A new species of the genus Dugesia is described from the Lake Ohrid region in the western part of the Balkan Peninsula, forming the first fully documented species description for this genus in the Ohrid area. The morphological species delimitation is supported by complementary molecular, karyological, and cytogenetic data available from the literature. Therefore, species delineation is based on a truly integrative approach. Further, a short account on the degree of freshwater planarian endemicity in the Ohrid region is provided. PMID:23840163

  20. Integrative taxonomy of a new species of planarian from the Lake Ohrid basin, including an analysis of biogeographical patterns in freshwater triclads from the Ohrid region (Platyhelminthes, Tricladida, Dugesiidae

    Directory of Open Access Journals (Sweden)

    Giacinta Stocchino

    2013-06-01

    Full Text Available A new species of the genus Dugesia is described from the Lake Ohrid region in the western part of the Balkan Peninsula, forming the first fully documented species description for this genus in the Ohrid area. The morphological species delimitation is supported by complementary molecular, karyological, and cytogenetic data available from the literature. Therefore, species delineation is based on a truly integrative approach. Further, a short account on the degree of freshwater planarian endemicity in the Ohrid region is provided.

  1. Checklist of the phyla Platyhelminthes, Xenacoelomorpha, Nematoda, Acanthocephala, Myxozoa, Tardigrada, Cephalorhyncha, Nemertea, Echiura, Brachiopoda, Phoronida, Chaetognatha, and Chordata (Tunicata, Cephalochordata, and Hemichordata) from the coasts of Turkey

    OpenAIRE

    ÇINAR, Melih Ertan

    2014-01-01

    In this paper, the current status of the species diversity of 13 phyla, namely Platyhelminthes, Xenacoelomorpha, Nematoda, Acanthocephala, Myxozoa, Tardigrada, Cephalorhyncha, Nemertea, Echiura, Brachiopoda, Phoronida, Chaetognatha, and Chordata (invertebrates, only Tunicata, Cephalochordata, and Hemichordata) along the coasts of Turkey is reviewed. Platyhelminthes was represented by 186 species, Chordata by 64 species, Nemertea by 26 species, Nematoda by 20 species, Xenacoelomorpha by 11 spe...

  2. First record of the family Pseudocerotidae (Platyhelminthes, Polycladida, Cotylea from the Persian Gulf, Iran

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    Zahra Khalili

    2009-12-01

    Full Text Available In this paper, two species of cotylean Platyhelminthes are recorded for the first time from Qeshm Island, Persian Gulf, Iran. Pictures are taken from living specimens to illustrate shape and colour, and stained sections and drawings are used to describe shape and organisation of some organs. Morphological characters of Persian Gulf specimens of Tytthosoceros lizardensis Newman & Cannon, 1996 are compared to those of the type specimens of this species.

  3. Discovery of platyhelminth-specific α/β-integrin families and evidence for their role in reproduction in Schistosoma mansoni.

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    Svenja Beckmann

    Full Text Available In all metazoa, the response of cells to molecular stimuli from their environment represents a fundamental principle of regulatory processes controlling cell growth and differentiation. Among the membrane-linked receptors mediating extracellular communication processes are integrin receptors. Besides managing adhesion to the extracellular matrix or to other cells, they arrange information flow into the cells by activating intracellular signaling pathways often acting synergistically through cooperation with growth factor receptors. Although a wealth of information exists on integrins in different model organisms, there is a big gap of knowledge for platyhelminths. Here we report on the in silico detection and reconstruction of α and β integrins from free-living and parasitic platyhelminths, which according to structural and phylogenetic analyses form specific clades separate from each other and from further metazoan integrins. As representative orthologs of parasitic platyhelminths we have cloned one beta-integrin (Smβ-Int1 and four alpha-integrins (Smα-Int1 - Smα-Int4 from Schistosoma mansoni; they were characterized by molecular and biochemical analyses. Evidence is provided that Smβ-Int1 interacts and co-localizes in the reproductive organs with known schistosome cellular tyrosine kinases (CTKs, of which the Syk kinase SmTK4 appeared to be the strongest interaction partner as shown by yeast two-hybrid analyses and coimmunoprecipitation experiments. By a novel RNAi approach with adult schistosomes in vitro we demonstrate for the first time multinucleated oocytes in treated females, indicating a decisive role Smβ-Int1 during oogenesis as phenotypically analyzed by confocal laser scanning microscopy (CLSM. Our findings provide a first comprehensive overview about platyhelminth integrins, of which the parasite group exhibits unique features allowing a clear distinction from the free-living groups. Furthermore, we shed first lights on the

  4. Staining of Platyhelminthes by herbal dyes: An eco-friendly technique for the taxonomist

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    Niranjan Kumar

    2015-11-01

    Full Text Available Aim: An environment compatible technique to stain Platyhelminthes, Fasciola gigantica, Gastrothylax crumenifer, Taenia solium, and Moniezia expansa using aqueous and alcoholic extract of sugar beet (Beta vulgaris, China rose (Hibiscus rosasinensis, and red rose (Rosa hybrida were described to minimized the deleterious effects of the synthetic dyes. Materials and Methods: Aqueous/ethanolic extracts of roses were extracted from the flowers while red beet was extracted from the roots. Results: Stained helminthes acquired a comparable level of pigmentation with the distinction of their internal structure in these natural dyes. The flukes (liver and rumen internal structure, oral and ventral/posterior sucker, cirrus sac, gravid uterus, testes, ovary, and vitallaria were appeared pink color in aqueous and alcoholic extract of either China or red rose and yellow to brown color in sugar beet stain. The interior of the proglottid of T. solium and M. expansa took yellow to brown color with good contrast in sugar beet stain and of pink to pink-red in China and red rose stain. Conclusion: The extract of roses (red rose followed by China rose followed by red beet possess the potential to replace the conventional stains in the taxonomic study of Platyhelminthes parasites.

  5. Atypical properties of a conventional calcium channel β subunit from the platyhelminth Schistosoma mansoni

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    Schneider Toni

    2008-03-01

    Full Text Available Abstract Background The function of voltage-gated calcium (Cav channels greatly depends on coupling to cytoplasmic accessory β subunits, which not only promote surface expression, but also modulate gating and kinetic properties of the α1 subunit. Schistosomes, parasitic platyhelminths that cause schistosomiasis, express two β subunit subtypes: a structurally conventional β subunit and a variant β subunit with unusual functional properties. We have previously characterized the functional properties of the variant Cavβ subunit. Here, we focus on the modulatory phenotype of the conventional Cavβ subunit (SmCavβ using the human Cav2.3 channel as the substrate for SmCavβ and the whole-cell patch-clamp technique. Results The conventional Schistosoma mansoni Cavβ subunit markedly increases Cav2.3 currents, slows macroscopic inactivation and shifts steady state inactivation in the hyperpolarizing direction. However, currents produced by Cav2.3 in the presence of SmCavβ run-down to approximately 75% of their initial amplitudes within two minutes of establishing the whole-cell configuration. This suppressive effect was independent of Ca2+, but dependent on intracellular Mg2+-ATP. Additional experiments revealed that SmCavβ lends the Cav2.3/SmCavβ complex sensitivity to Na+ ions. A mutant version of the Cavβ subunit lacking the first forty-six amino acids, including a string of twenty-two acidic residues, no longer conferred sensitivity to intracellular Mg2+-ATP and Na+ ions, while continuing to show wild type modulation of current amplitude and inactivation of Cav2.3. Conclusion The data presented in this article provide insights into novel mechanisms employed by platyhelminth Cavβ subunits to modulate voltage-gated Ca2+ currents that indicate interactions between the Ca2+ channel complex and chelated forms of ATP as well as Na+ ions. These results have potentially important implications for understanding previously unknown mechanisms by

  6. [The influence of Janicki cercomer theory on the development of platyhelminthes systematics and evolution investigations].

    Science.gov (United States)

    Pojmańska, Teresa

    2005-01-01

    The aim of this article was to present the development of ideas about the provenience of parasitic helminths and the phylogenetical relationships within this taxon, since the publication of the "cercomer theory" just to nowadays. The following essentials of the Janicki theory are outlined: main differences between free-living Turbellaria and parasitic platyhelminths (ciliated epithelium in Turbellaria versus unciliated surface in the others); universality of the cercomer presence in Monogenea, Digenea and Cestoda; evolutionary changes in the morphology and function of the cercomer; homology of the caudal appendices of all parasitic helminths; the subsequent evolution of parasitic platyhelminthes from the ancestor to Monogena, Digenea and Cestoda; proposition to establish a new common taxon--Cercomerophora--for these three groups. In this background the evolution of evolutionary ideas is reviewed, divided into two periods: up to the eighties of the XX century, and up to date. The first period can be characterised by the criticism of some points of the "cercomer theory" and formulation of some new hypotheses; these are those of Fuhrmann, Bychovsky, Llewellyn, Price and Malmberg, which: questioned the homology of the cercarial tail with the caudal appendices of Monogenea and Cestoda; rejected Digenea from the common group; established the common taxon--Cercomeromorpha--comprising only Monogenea and Cestoda; opposed the idea of radial evolution of three main groups of Platyhelmithes (Turbellaria, Digenea and Cercomeromorpha) to the idea of subsequent evolution presented by Janicki. The differences between these last hypotheses are also underlined, arising mainly from the different ideas on the importance of particular features as the evolutionary indicators of affinities between and within the taxons. As to the hypotheses dealing with the evolution of particular groups of parasitic platyhelminths formulated at the same period, the publications of Freeman and Jarecka

  7. Problematic barcoding in flatworms: A case-study on monogeneans and rhabdocoels (Platyhelminthes

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    Maarten Vanhove

    2013-12-01

    Full Text Available Some taxonomic groups are less amenable to mitochondrial DNA barcoding than others. Due to the paucity of molecular information of understudied groups and the huge molecular diversity within flatworms, primer design has been hampered. Indeed, all attempts to develop universal flatworm-specific COI markers have failed so far. We demonstrate how high molecular variability and contamination problems limit the possibilities for barcoding using standard COI-based protocols in flatworms. As a consequence, molecular identification methods often rely on other widely applicable markers. In the case of Monogenea, a very diverse group of platyhelminth parasites, and Rhabdocoela, representing one-fourth of all free-living flatworm taxa, this has led to a relatively high availability of nuclear ITS and 18S/28S rDNA sequences on GenBank. In a comparison of the effectiveness in species assignment we conclude that mitochondrial and nuclear ribosomal markers perform equally well. In case intraspecific information is needed, rDNA sequences can guide the selection of the appropriate (i.e. taxon-specific COI primers if available.

  8. Comparative study of adaptive radiations with an example using parasitic flatworms (Platyhelminthes): Cercomeria

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, D.R.; McLennan, D.A. (Univ. of Toronto, Ontario (Canada))

    1993-11-01

    Studies of adaptive radiations require robust phylogenies, estimates of species numbers for monophyletic groups within clades, assessments of the adaptive value of putative key innovations, and estimates of the frequency of speciation modes. Four criteria are necessary to identify an adaptive radiation within the parasitic platyhelminths: (1) a group contains significantly more species than its sister group, (2) species richness is apomorphic, (3) apomorphic traits enhance the potential for adaptively driven modes of speciation (sympatric speciation and speciation by peripheral isolation via host switching), and (4) the frequency of adaptively driven speciation modes is high within the group when compared with data from free-living groups. Only the species-rich Monogenea fulfill all four criteria. The Digenea and Eucestoda also are more species rich than their sister groups, their species richness is derived, and they possess unique characters that increase the potential for host switching to occur. However, because there is not enough information to determine whether the frequency of adaptive modes of speciation is high for those groups, we cannot yet assert that their radiations have been adaptive. 102 refs., 3 figs., 1 tab.

  9. Two new families (Acari: Alicorhagiidae and Platyhelminthes: Prorhynchidae) reported for the Hungarian fauna From leaf litter in the Bükk Mountains

    OpenAIRE

    Pfliegler, W.P.; Bolton, S.J.

    2016-01-01

    Two new members of the Hungarian fauna are reported, both of them were collected in beech forest leaf litter in the Bükk Mountains, North-East Hungary: Alicorhagia fragilis Berlese, 1910 (Arthropoda: Arachnida: Acari: Sarcopti-formes: Endeostigmata: Alicorhagiidae) and Geocentrophora baltica (Kennel, 1883) (Platyhelminthes: Rhabditophora: Trepaxonemata: Amplimatricata: 'Lecithoepitheliata': Prorhynchida: Prorhynchidae). The families Alicorhagiidae and Prorhynchidae both represent...

  10. Venus kinase receptors control reproduction in the platyhelminth parasite Schistosoma mansoni.

    Science.gov (United States)

    Vanderstraete, Mathieu; Gouignard, Nadège; Cailliau, Katia; Morel, Marion; Hahnel, Steffen; Leutner, Silke; Beckmann, Svenja; Grevelding, Christoph G; Dissous, Colette

    2014-05-01

    The Venus kinase receptor (VKR) is a single transmembrane molecule composed of an intracellular tyrosine kinase domain close to that of insulin receptor and an extracellular Venus Flytrap (VFT) structure similar to the ligand binding domain of many class C G protein coupled receptors. This receptor tyrosine kinase (RTK) was first discovered in the platyhelminth parasite Schistosoma mansoni, then in a large variety of invertebrates. A single vkr gene is found in most genomes, except in S. mansoni in which two genes Smvkr1 and Smvkr2 exist. VKRs form a unique family of RTKs present only in invertebrates and their biological functions are still to be discovered. In this work, we show that SmVKRs are expressed in the reproductive organs of S. mansoni, particularly in the ovaries of female worms. By transcriptional analyses evidence was obtained that both SmVKRs fulfill different roles during oocyte maturation. Suppression of Smvkr expression by RNA interference induced spectacular morphological changes in female worms with a strong disorganization of the ovary, which was dominated by the presence of primary oocytes, and a defect of egg formation. Following expression in Xenopus oocytes, SmVKR1 and SmVKR2 receptors were shown to be activated by distinct ligands which are L-Arginine and calcium ions, respectively. Signalling analysis in Xenopus oocytes revealed the capacity of SmVKRs to activate the PI3K/Akt/p70S6K and Erk MAPK pathways involved in cellular growth and proliferation. Additionally, SmVKR1 induced phosphorylation of JNK (c-Jun N-terminal kinase). Activation of JNK by SmVKR1 was supported by the results of yeast two-hybrid experiments identifying several components of the JNK pathway as specific interacting partners of SmVKR1. In conclusion, these results demonstrate the functions of SmVKR in gametogenesis, and particularly in oogenesis and egg formation. By eliciting signalling pathways potentially involved in oocyte proliferation, growth and migration

  11. Venus kinase receptors control reproduction in the platyhelminth parasite Schistosoma mansoni.

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    Mathieu Vanderstraete

    2014-05-01

    Full Text Available The Venus kinase receptor (VKR is a single transmembrane molecule composed of an intracellular tyrosine kinase domain close to that of insulin receptor and an extracellular Venus Flytrap (VFT structure similar to the ligand binding domain of many class C G protein coupled receptors. This receptor tyrosine kinase (RTK was first discovered in the platyhelminth parasite Schistosoma mansoni, then in a large variety of invertebrates. A single vkr gene is found in most genomes, except in S. mansoni in which two genes Smvkr1 and Smvkr2 exist. VKRs form a unique family of RTKs present only in invertebrates and their biological functions are still to be discovered. In this work, we show that SmVKRs are expressed in the reproductive organs of S. mansoni, particularly in the ovaries of female worms. By transcriptional analyses evidence was obtained that both SmVKRs fulfill different roles during oocyte maturation. Suppression of Smvkr expression by RNA interference induced spectacular morphological changes in female worms with a strong disorganization of the ovary, which was dominated by the presence of primary oocytes, and a defect of egg formation. Following expression in Xenopus oocytes, SmVKR1 and SmVKR2 receptors were shown to be activated by distinct ligands which are L-Arginine and calcium ions, respectively. Signalling analysis in Xenopus oocytes revealed the capacity of SmVKRs to activate the PI3K/Akt/p70S6K and Erk MAPK pathways involved in cellular growth and proliferation. Additionally, SmVKR1 induced phosphorylation of JNK (c-Jun N-terminal kinase. Activation of JNK by SmVKR1 was supported by the results of yeast two-hybrid experiments identifying several components of the JNK pathway as specific interacting partners of SmVKR1. In conclusion, these results demonstrate the functions of SmVKR in gametogenesis, and particularly in oogenesis and egg formation. By eliciting signalling pathways potentially involved in oocyte proliferation, growth

  12. Complete Sequence of the mitochondrial genome of the tapeworm Hymenolepis diminuta: Gene arrangements indicate that platyhelminths are eutrochozoans

    Energy Technology Data Exchange (ETDEWEB)

    von Nickisch-Rosenegk, Markus; Brown, Wesley M.; Boore, Jeffrey L.

    2001-01-01

    Using ''long-PCR'' we have amplified in overlapping fragments the complete mitochondrial genome of the tapeworm Hymenolepis diminuta (Platyhelminthes: Cestoda) and determined its 13,900 nucleotide sequence. The gene content is the same as that typically found for animal mitochondrial DNA (mtDNA) except that atp8 appears to be lacking, a condition found previously for several other animals. Despite the small size of this mtDNA, there are two large non-coding regions, one of which contains 13 repeats of a 31 nucleotide sequence and a potential stem-loop structure of 25 base pairs with an 11-member loop. Large potential secondary structures are identified also for the non-coding regions of two other cestode mtDNAs. Comparison of the mitochondrial gene arrangement of H. diminuta with those previously published supports a phylogenetic position of flatworms as members of the Eutrochozoa, rather than being basal to either a clade of protostomes or a clade of coelomates.

  13. No evidence for a culturable bacterial tetrodotoxin producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae) and Stylochoplana sp. (Platyhelminthes: Polycladida).

    Science.gov (United States)

    Salvitti, Lauren R; Wood, Susanna A; McNabb, Paul; Cary, Stephen Craig

    2015-02-01

    Tetrodotoxin (TTX) is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia) and Stylochoplana sp. (Platyhelminthes). Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography-mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0), suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely. PMID:25635464

  14. No Evidence for a Culturable Bacterial Tetrodotoxin Producer in Pleurobranchaea maculata (Gastropoda: Pleurobranchidae and Stylochoplana sp. (Platyhelminthes: Polycladida

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    Lauren R. Salvitti

    2015-01-01

    Full Text Available Tetrodotoxin (TTX is a potent neurotoxin found in the tissues of many taxonomically diverse organisms. Its origin has been the topic of much debate, with suggestions including endogenous production, acquisition through diet, and symbiotic bacterial synthesis. Bacterial production of TTX has been reported in isolates from marine biota, but at lower than expected concentrations. In this study, 102 strains were isolated from Pleurobranchaea maculata (Opisthobranchia and Stylochoplana sp. (Platyhelminthes. Tetrodotoxin production was tested utilizing a recently developed sensitive method to detect the C9 base of TTX via liquid chromatography—mass spectrometry. Bacterial strains were characterized by sequencing a region of the 16S ribosomal RNA gene. To account for the possibility that TTX is produced by a consortium of bacteria, a series of experiments using marine broth spiked with various P. maculata tissues were undertaken. Sixteen unique strains from P. maculata and one from Stylochoplana sp. were isolated, representing eight different genera; Pseudomonadales, Actinomycetales, Oceanospirillales, Thiotrichales, Rhodobacterales, Sphingomonadales, Bacillales, and Vibrionales. Molecular fingerprinting of bacterial communities from broth experiments showed little change over the first four days. No C9 base or TTX was detected in isolates or broth experiments (past day 0, suggesting a culturable microbial source of TTX in P. maculata and Stylochoplana sp. is unlikely.

  15. Lista preliminar dos platelmintes e anelídeos (Platyhelminthes e Annelida) terrestres dos arquipélagos da madeira e das selvagens

    OpenAIRE

    Paulo A V Borges

    2008-01-01

    Apresenta -se uma lista preliminar dos filos Platyhelminthes e Annelida terrestres dos arquipélagos da Madeira e Selvagens. Com base na recente lista de espécies animais terrestres da Europa, projecto “Fauna Europaea” (http://www.faunaeur.org), listam -se sete espécies de platelmintes e 36 espécies de anelídeos terrestres. Em adição aos grupos de animais listados em detalhe em outros capítulos deste livro (Nematoda, Mollusca, Arthropoda, Chordata), a diversidade de dois outros grupos de anima...

  16. First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae, um ectosimbionte de larvas de Corydalidae (Maegaloptera

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    Susana Trivinho-Strixino

    2012-09-01

    Full Text Available First record of larvae of Chironomidae (Insecta, Diptera as prey of Temnocephala sp. (Platyhelminthes, Temnocephalidae, an ectosymbiont on larvae of Corydalidae (Megaloptera. This study constitutes the first record of Temnocephala Blanchard, an ectosymbiont on Corydalidae, as a possible predator of chironomid larvae. Twenty-eight Corydalidae larvae (Corydalus and Protochauliodes were examined under stereomicroscopic in search for Temnocephala and Chironomidae larvae, of which five megalopteran larvae had 24 Temnocephala sp. associated. Furthermore, eight of these Temnocephala worms had chironomid larvae in their gut contents, an interaction previously unknown. Gut content analyses revealed Corynoneura as the commonest chironomid, but larvae of Larsia, Rheotanytarsus and Tanytarsus were recorded as well. This study included Corydalus and Protochauliodes as hosts for Temnocephala, which might be important for this worm dispersion and population dynamics.Primeiro registro de larvas de Chironomidae como presas de Temnocephala sp. (Platyhelminthes, Temnocephalidae, um ectosimbionte de larvas de Corydalidae (Maegaloptera. Este estudo constitui o primeiro registro de Temnocephala Blanchard (Platyhelminthes, Temnocephalidae, um ectosimbionte em larvas de Megaloptera, como um possível predador de larvas de Chironomidae. Vinte e oito larvas de Corydalidae (Corydalus e Protochauliodes foram examinadas sobre estereomicroscópio na busca por Temnocephala e larvas de Chironomidae, das quais cinco larvas de Megaloptera continham 24 Temnocephala sp. associadas. Além disso, oito Temnocephala possuíam em seu conteúdo estomacal larvas de Chironomidae, uma interação desconhecida anteriormente. A análise do conteúdo estomacal revelou Corynoneura como o quironomídeo mais abundante, e também algumas larvas de Larsia, Rheotanytarsus e Tanytarsus. Este estudo inclui Corydalus e Protochauliodes como hospedeiros de Temnocephala, os quais podem ser importantes

  17. Transfection of Platyhelminthes

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    Bárbara Moguel

    2015-01-01

    Full Text Available Flatworms are one of the most diverse groups within Lophotrochozoa with more than 20,000 known species, distributed worldwide in different ecosystems, from the free-living organisms in the seas and lakes to highly specialized parasites living in a variety of hosts, including humans. Several infections caused by flatworms are considered major neglected diseases affecting countries in the Americas, Asia, and Africa. For several decades, a particular interest on free-living flatworms was due to their ability to regenerate considerable portions of the body, implying the presence of germ cells that could be important for medicine. The relevance of reverse genetics for this group is clear; understanding the phenotypic characteristics of specific genes will shed light on developmental traits of free-living and parasite worms. The genetic manipulation of flatworms will allow learning more about the mechanisms for tissue regeneration, designing new and more effective anthelmintic drugs, and explaining the host-parasite molecular crosstalk so far partially inaccessible for experimentation. In this review, availability of transfection techniques is analyzed across flatworms, from the initial transient achievements to the stable manipulations now developed for free-living and parasite species.

  18. Transfection of Platyhelminthes

    Science.gov (United States)

    Moguel, Bárbara; Bobes, Raúl J.; Carrero, Julio C.; Laclette, Juan P.

    2015-01-01

    Flatworms are one of the most diverse groups within Lophotrochozoa with more than 20,000 known species, distributed worldwide in different ecosystems, from the free-living organisms in the seas and lakes to highly specialized parasites living in a variety of hosts, including humans. Several infections caused by flatworms are considered major neglected diseases affecting countries in the Americas, Asia, and Africa. For several decades, a particular interest on free-living flatworms was due to their ability to regenerate considerable portions of the body, implying the presence of germ cells that could be important for medicine. The relevance of reverse genetics for this group is clear; understanding the phenotypic characteristics of specific genes will shed light on developmental traits of free-living and parasite worms. The genetic manipulation of flatworms will allow learning more about the mechanisms for tissue regeneration, designing new and more effective anthelmintic drugs, and explaining the host-parasite molecular crosstalk so far partially inaccessible for experimentation. In this review, availability of transfection techniques is analyzed across flatworms, from the initial transient achievements to the stable manipulations now developed for free-living and parasite species. PMID:26090388

  19. Light and electron microscopic studies of the intestinal epithelium in Notoplana humilis (Platyhelminthes, Polycladida): the contribution of mesodermal/gastrodermal neoblasts to intestinal regeneration.

    Science.gov (United States)

    Okano, Daisuke; Ishida, Sachiko; Ishiguro, Sei-ichi; Kobayashi, Kazuya

    2015-12-01

    Some free-living flatworms in the phylum Platyhelminthes possess strong regenerative capability that depends on putative pluripotent stem cells known as neoblasts. These neoblasts are defined based on several criteria, including their proliferative capacity and the presence of cellular components known as chromatoid bodies. Polyclads, which are marine flatworms, have the potential to be a good model system for stem cell research, yet little information is available regarding neoblasts and regeneration. In this study, transmission electron microscopy and immunostaining analyses, using antibodies against phospho-histone H3 and BrdU, were used to identify two populations of neoblasts in the polyclad Notoplana humilis: mesodermal neoblasts (located in the mesenchymal space) and gastrodermal neoblasts (located within the intestine, where granular club cells and phagocytic cells are also located). Light and electron microscopic analyses also suggested that phagocytic cells and mesodermal/gastrodermal neoblasts, but not granular club cells, migrated into blastemas and remodeled the intestine during regeneration. Therefore, we suggest that, in polyclads, intestinal regeneration is accomplished by mechanisms underlying both morphallaxis (remodeling of pre-existing tissues) and epimorphosis (de novo tissue formation derived from mesodermal/gastrodermal neoblasts). Based on the assumption that gastrodermal neoblasts, which are derived from mesodermal neoblasts, are intestinal stem cells, we propose a model to study intestinal regeneration.

  20. Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea infecting the south European toothcarp Aphanius fasciatus (Valenciennes (Teleostei, Cyprinodontidae from a hypersaline environment in Italy

    Directory of Open Access Journals (Sweden)

    Huyse Tine

    2011-06-01

    Full Text Available Abstract Background Historically, non-native species of Gambusia (Poeciliidae have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes (Teleostei: Cyprinodontidae as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea. A subsequent morphological and molecular study identified this as being a new species. Results Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas. Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2. This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt. Conclusions The ability of G. salinae n. sp. to tolerate a wide

  1. Evolutionary processes involved in the diversification of chelonian and mammal polystomatid parasites (Platyhelminthes, Monogenea, Polystomatidae) revealed by palaeoecology of their hosts.

    Science.gov (United States)

    Héritier, Laurent; Badets, Mathieu; Du Preez, Louis H; Aisien, Martins S O; Lixian, Fan; Combes, Claude; Verneau, Olivier

    2015-11-01

    Polystomatid flatworms (Platyhelminthes) are monogenean parasites that infect exclusively aquatic or semi-aquatic sarcopterygians such as the Australian lungfish, amphibians, freshwater turtles and the African common hippopotamus. Previous studies on the phylogenetic relationships of these parasites, excluding Oculotrema hippopotami infecting common hippos, showed a global coevolution between hosts and their parasites at a macroevolutionary scale. These studies also demonstrated a strong correlation between the diversification of early neobatrachian polystomes and Gondwana breakup in the Mesozoic period. However the origin of chelonian polystomes is still in question as a switch from presumably primitive aquatic amniotes to turtles at the time of their first appearance, or soon after during their radiation, was assumed. In order to resolve this sticking point, we extended the phylogeny of polystomes with broader parasite sampling, i.e. 55 polystome species including Nanopolystoma tinsleyi a polystome infecting caecilians and O. hippopotami, and larger set of sequence data covering two nuclear and two mitochondrial genes coding for the ribosomal RNA 18S and 28S, the Cytochrome c Oxidase I and the ribosomal RNA 12S, respectively. The secondary structure of nuclear rRNAs genes (stems and loops) was taken into account for sequence alignments and Bayesian analyses were performed based on the appropriate models of evolution selected independently for the four designed partitions. Molecular calibrations were also conducted for dating the main speciation events in the polystome tree. The phylogenetic position of chelonian parasites that are phylogenetically closer to N. tinsleyi than all other amphibian polystomes and molecular time estimates suggest that these parasites originated following a switch from caecilians, at a geological period when primitive turtles may already have adapted to an aquatic life style, i.e. at about 178Million years ago, or a little later when

  2. Distribution and origin of chromosomal races in the freshwater planarian Dugesia polychroa (Turbellaria : Tricladida)

    NARCIS (Netherlands)

    Beukeboom, Leo W.; Weinzierl, Rolf P.; Reed, Kent M.; Michiels, Nico K.

    1996-01-01

    We present a karyotypic survey of the European freshwater planarian Dugesia polychroa, detailing frequencies of diploid and polyploid forms from 35 localities in seven countries. In this hermaphroditic species, diploids reproduce sexually and polyploids by pseudogamous parthenogenesis. Previous labo

  3. Developmental diversity in free-living flatworms

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    Martín-Durán José

    2012-03-01

    Full Text Available Abstract Flatworm embryology has attracted attention since the early beginnings of comparative evolutionary biology. Considered for a long time the most basal bilaterians, the Platyhelminthes (excluding Acoelomorpha are now robustly placed within the Spiralia. Despite having lost their relevance to explain the transition from radially to bilaterally symmetrical animals, the study of flatworm embryology is still of great importance to understand the diversification of bilaterians and of developmental mechanisms. Flatworms are acoelomate organisms generally with a simple centralized nervous system, a blind gut, and lacking a circulatory organ, a skeleton and a respiratory system other than the epidermis. Regeneration and asexual reproduction, based on a totipotent neoblast stem cell system, are broadly present among different groups of flatworms. While some more basally branching groups - such as polyclad flatworms - retain the ancestral quartet spiral cleavage pattern, most flatworms have significantly diverged from this pattern and exhibit unique strategies to specify the common adult body plan. Most free-living flatworms (i.e. Platyhelminthes excluding the parasitic Neodermata are directly developing, whereas in polyclads, also indirect developers with an intermediate free-living larval stage and subsequent metamorphosis are found. A comparative study of developmental diversity may help understanding major questions in evolutionary biology, such as the evolution of cleavage patterns, gastrulation and axial specification, the evolution of larval types, and the diversification and specialization of organ systems. In this review, we present a thorough overview of the embryonic development of the different groups of free-living (turbellarian platyhelminths, including the Catenulida, Macrostomorpha, Polycladida, Lecithoepitheliata, Proseriata, Bothrioplanida, Rhabdocoela, Fecampiida, Prolecithophora and Tricladida, and discuss their main features

  4. Sex-inducing effect of a hydrophilic fraction on reproductive switching in the planarian Dugesia ryukyuensis (Seriata, Tricladida

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    Hoshi Motonori

    2011-10-01

    Full Text Available Abstract Background The mechanisms underlying the switching from an asexual to a sexual mode of reproduction, and vice versa, remain unknown in metazoans. In planarians, asexual worms acquire cryptic sexuality when fed with sexual worms, indicating that sexual worms contain a sex-inducing substance. Although such a chemical compound will provide clues about the mechanisms underlying the switching, information on the sex-inducing substance is poor. In order to identify this substance, we have established an assay system for sexual induction in asexual worms of Dugesia ryukyuensis by feeding them with sexual worms. Here, we carried out an isolation study on the sex-inducing substance using this assay system. Results After centrifugation of sexual worms homogenised in saline solution, we found that not only did the precipitate have a sex-inducing effect on the asexual worms, which has been shown previously, but the cytosolic fraction did as well. We confirmed that the sex-inducing activity in the cytosolic fraction was recovered in a hydrophilic fraction separated on an octadecylsilane (ODS column. We showed that the sex-inducing substance in the hydrophilic fraction is papain-resistant and a putative low-molecular-weight compound of less than 500. We also suggest the presence of an enhancer of sexual induction with a molecular weight (MW of more than 5 K in the hydrophilic fraction. Conclusion Our experiments showed the existence of a sex-inducing substance and an enhancer of sex-induction in a hydrophilic fraction, and a putative hydrophobic sex-inducing substance in the precipitate. Sexual induction in the asexual worms might be triggered by additive or synergistic effects of these chemical compounds.

  5. Genetic differences among several species of Tricladida from the relict Lake Ohrid as revealed by enzyme electrophoresis.

    Science.gov (United States)

    Sywula, Tadeusz; Krstanovski, Zdravko; Tasevska, Orhideja; Sell, Jerzy; Kretowicz, Tomasz

    2003-01-01

    Six endemic and two widely distributed species living in Lake Ohrid were studied. In general, these hermaphroditic animals displayed no signs of departure from Hardy-Weinberg equilibrium. Genetic variation in all but one of the endemic species was of the same extent as that in geographically wide ranging invertebrates. On the other hand, the Lake Ohrid population of the common European species Dendrocoelum lacteum was monomorphic at all loci examined. D. sanctinaumi, one of the endemic species, exhibited a clear genetic subdivision into spring and littoral subpopulations. The genetic differentiation of Crenobia alpina alpina and C. a. montenigrina proved commensurable to that of well separated species from other genera. The data suggest that the separation of particular lineages in the set of Lake Ohrid endemics was widely dispersed over time. PMID:14686654

  6. Insight into the role of cetaceans in the life cycle of the tetraphyllideans (Platyhelminthes: Cestoda).

    Science.gov (United States)

    Aznar, F J; Agustí, C; Littlewood, D T J; Raga, J A; Olson, P D

    2007-02-01

    Four types of tetraphyllidean larvae infect cetaceans worldwide: two plerocercoids differing in size, 'small' (SP) and 'large' (LP), and two merocercoids referred to as Phyllobothrium delphini and Monorygma grimaldii. The latter merocercoid larvae parasitize marine mammals exclusively and exhibit a specialised cystic structure. Adult stages are unknown for any of the larvae and thus the role of cetaceans in the life cycle of these species has been a long-standing problem. The SP and LP forms are thought to be earlier stages of P. delphini and M. grimaldii that are presumed to infect large pelagic sharks that feed on cetaceans. A molecular analysis of the D2 variable region of the large subunit ribosomal DNA gene based on several individuals of each larval type collected from three Mediterranean species of cetaceans showed consistent and unique molecular signatures for each type regardless of host species or site of infection. The degree of divergence suggested that LP, P. delphini and M. grimaldii larvae may represent separate species, whereas SP may be conspecific with M. grimaldii. In all host species, individuals of SP accumulated in the gut areas in which the lymphoid tissue was especially developed. We suggest therefore that these larvae use the lymphatic system to migrate to the abdominal peritoneum and mesenteries where they develop into forms recognizable as M. grimaldii. The plerocercoid stage of P. delphini remains unknown. In a partial phylogenetic tree of the Tetraphyllidea, all larvae formed a clade that included a representative of the genus Clistobothrium, some species of which parasitize sharks such as the great white which is known to feed on cetaceans. A bibliographic examination of tetraphyllidean infections in marine mammals indicated that these larvae are acquired mostly offshore. In summary, the evidence suggests that cetaceans play a significant role in the life cycle of these larvae. In addition, it seems clear that cetaceans act as natural intermediate hosts for P. delphini and M. grimaldii, as within these hosts they undergo development from the plerocercoid stage to the merocercoid stage. Because tetraphyllidean species use fish, cephalopods and other marine invertebrates as intermediate hosts, the inclusion of cetaceans in the life cycle would have facilitated their transmission to apex predators such as the large, lamnid sharks. The biological significance of infections of LP in cetaceans is unclear, but infections do not seem to be accidental as such larvae show high prevalence and abundance as well as a high degree of site specificity, particularly in the anal crypts and bile ducts. PMID:17161403

  7. Molecular identification of Fasciola spp. (Digenea: Platyhelminthes in cattle from Vietnam

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    Nguyen S.

    2012-02-01

    Full Text Available Fasciola spp. were collected from naturally infected cattle at a local abattoir of Khanh Hoa province, Vietnam, for morphological and genetic investigations. Microscopic examination detected no sperm cells in the seminal vesicles, suggesting a parthenogenetic reproduction of the flukes. Analyses of sequences from the first and second internal transcribed spacers (ITS1 and ITS2 of the ribosomal RNA revealed that 13 out of 16 isolates were of Fasciola gigantica type, whereas three isolates presented a hybrid sequence from F. gigantica and Fasciola hepatica. Interestingly, all the mitochondrial sequences (partial COI and NDI were of F. gigantica type, suggesting that the maternal lineage of the hybrid form is from F. gigantica. No intra-sequence variation was detected.

  8. Co-Speciation of the Ectoparasite Gyrodactylus teuchis (Monogenea, Platyhelminthes and Its Salmonid Hosts.

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    Christoph Hahn

    Full Text Available Co-speciation is a fundamental concept of evolutionary biology and intuitively appealing, yet in practice hard to demonstrate as it is often blurred by other evolutionary processes. We investigate the phylogeographic history of the monogenean ectoparasites Gyrodactylus teuchis and G. truttae on European salmonids of the genus Salmo. Mitochondrial cytochrome oxidase subunit 1 and the nuclear ribosomal internal transcribed spacer 2 were sequenced for 189 Gyrodactylus individuals collected from 50 localities, distributed across most major European river systems, from the Iberian- to the Balkan Peninsula. Despite both anthropogenic and naturally caused admixture of the principal host lineages among major river basins, co-phylogenetic analyses revealed significant global congruence for host and parasite phylogenies, providing firm support for co-speciation of G. teuchis and its salmonid hosts brown trout (S. trutta and Atlantic salmon (S. salar. The major split within G. teuchis, coinciding with the initial divergence of the hosts was dated to ~1.5 My BP, using a Bayesian framework based on an indirect calibration point obtained from the host phylogeny. The presence of G. teuchis in Europe thus predates some of the major Pleistocene glaciations. In contrast, G. truttae exhibited remarkably low intraspecific genetic diversity. Given the direct life cycle and potentially high transmission potential of gyrodactylids, this finding is interpreted as indication for a recent emergence (<60 ky BP of G. truttae via a host-switch. Our study thus suggests that instances of two fundamentally different mechanisms of speciation (co-speciation vs. host-switching may have occurred on the same hosts in Europe within a time span of less than 1.5 My in two gyrodactylid ectoparasite species.

  9. Taenia saginata Goeze, 1872 (Platyhelminthes: Cestoda: Taeniidae from an indigenous native from Tierra del Fuego, Chile

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    Eduardo I. Faúndez

    2015-06-01

    Full Text Available First record of Taenia saginata from an indigenous from Tierra del Fuego (Chilean Patagonia is reported, from museum material of the year 1902. The importance of the record is discussed. Illustrations of the specimen are given.

  10. Spermiogenesis and spermultrastructure in Thylacorhynchus ambronensis (Schizorhynchia, Kalyptorhynchia, Platyhelminthes)

    OpenAIRE

    Watson, N.A.; Schockaert, E.R.

    1996-01-01

    Comprehensive ultrastructural investigation of spermiogenesis and the mature sperm in Thylacorhynchus ambronensis revealed a number of features valuable for cladistic analysis. Two basal bodies lie on either side of an intercentriolar body in the zone of differentiation of the spermatid, but only one develops into a normal flagellum while the other remains as a small bud, eventually disappearing. Structures within and surrounding the two basal bodies differ, and, contrary to observations in a...

  11. Platyhelminthes, Trematoda, Digenea Carus, 1863: distribution extension in Argentina and new anura and Ophidia hosts

    OpenAIRE

    2010-01-01

    The aim of this paper is to increase the knowledge on the diversity of digenean parasites in ophidians and anurans from northeastern Argentina. Specimens of the snakes Eunectes notaeus, Hydrodynastes gigas, Micrurus corallinus, Philodryas sp. and Sibynomorphus sp., and the anurans Rhinella schneideri, Phyllomedusa azurea and Leptodactylus latrans were examined. Twelve digenean species were identified: Catadiscus corderoi Mañé-Garzón, 1958, Catadiscus dolichocotyle (Cohn, 1903), Catadiscus uru...

  12. The Epidemiology of Ligula intestinalis (Phylum Platyhelminthes) within the Cyprinid Populations Inhabiting the Danubian Delta Area

    OpenAIRE

    Laura Daniela Urdes; Marius Hangan

    2013-01-01

    This prevalence study was conducted between the years 2003 and 2008. The survey aimed at assessing the occurrence of the plerocercoid Ligula intestinalis within five cyprinid populations, cyprinus carpio, carassius gibelio, hypophtalmichthys molitrix, ctenopharingodon idella and abramis brama, from four natural complexes: Sontea-Fortuna, Gorgova-Uzlina, Dunavat-Dranov and Razim-Sinoie. Of the four study sites, the highest frequency of the disease was recorded within the Razim-Sinoie lakes, pr...

  13. The Epidemiology of Ligula intestinalis (Phylum Platyhelminthes within the Cyprinid Populations Inhabiting the Danubian Delta Area

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    Laura Daniela Urdes

    2013-05-01

    Full Text Available This prevalence study was conducted between the years 2003 and 2008. The survey aimed at assessing the occurrence of the plerocercoid Ligula intestinalis within five cyprinid populations, cyprinus carpio, carassius gibelio, hypophtalmichthys molitrix, ctenopharingodon idella and abramis brama, from four natural complexes: Sontea-Fortuna, Gorgova-Uzlina, Dunavat-Dranov and Razim-Sinoie. Of the four study sites, the highest frequency of the disease was recorded within the Razim-Sinoie lakes, probably due to an apparently higher number of piscivorous birds and copepods that may have inhabited this area during the study time period. Only A. brama and H. molitrix were found infected by the helminth, with a mean prevalence of the cases in A. brama of 16.31% and in H. molitrix of 13.06%.

  14. The karyotypes of two Dugesia species from Corfu, Greece (Platyhelminthes, Turbellaria)

    NARCIS (Netherlands)

    Ball, Ian R.

    1979-01-01

    Dugesia gonocephala (Dugès, 1830) and D. polychroa (Schmidt, 1861), collected from the Greek island of Corfu, have been investigated karyologically. The former is a sexual diploid (2n = 16) in which all the chromosomes are metacentric. The latter is a sexual diploid (2n = 8) with one submetacentric

  15. A naturally occurring omega current in a Kv3 family potassium channel from a platyhelminth

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    Spencer Andrew N

    2008-06-01

    Full Text Available Abstract Background Voltage-gated ion channels are membrane proteins containing a selective pore that allows permeable ions to transit the membrane in response to a change in the transmembrane voltage. The typical selectivity filter in potassium channels is formed by a tetrameric arrangement of the carbonyl groups of the conserved amino-acid sequence Gly-Tyr-Gly. This canonical pore is opened or closed by conformational changes that originate in the voltage sensor (S4, a transmembrane helix with a series of positively charged amino acids. This sensor moves through a gating pore formed by elements of the S1, S2 and S3 helices, across the plane of the membrane, without allowing ions to pass through the membrane at that site. Recently, synthetic mutagenesis studies in the Drosophila melanogaster Shaker channel and analysis of human disease-causing mutations in sodium channels have identified amino acid residues that are integral parts of the gating-pore; when these residues are mutated the proteins allow a non-specific cation current, known as the omega current, to pass through the gating-pore with relatively low selectivity. Results The N.at-Kv3.2 potassium channel has an unusual weak inward rectifier phenotype. Several mutations of two amino acids in the voltage sensing (S4 transmembrane helix change the phenotype to a typical delayed rectifier. The inward rectifier channels (wild-type and mutant are sensitive to 4-aminopyridine (4-AP but not tetra-ethyl ammonium (TEA, whereas the delayed rectifier mutants are sensitive to TEA but not 4-AP. The inward rectifier channels also manifest low cation selectivity. The relative selectivity for different cations is sensitive to specific mutations in the S4 helix, Conclusion N.at-Kv3.2, a naturally occurring potassium channel of the Kv3 sequence family, mediates ion permeation through a modified gating pore, not the canonical, highly selective pore typical of potassium channels. This channel has evolved to yield qualitatively different ion permeability when compared to all other members of this gene family.

  16. Schmidtea mediterranea phylogeography: an old species surviving on a few Mediterranean islands?

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    Pala Maria

    2011-09-01

    Full Text Available Abstract Background Schmidtea mediterranea (Platyhelminthes, Tricladida, Continenticola is found in scattered localities on a few islands and in coastal areas of the western Mediterranean. Although S. mediterranea is the object of many regeneration studies, little is known about its evolutionary history. Its present distribution has been proposed to stem from the fragmentation and migration of the Corsica-Sardinia microplate during the formation of the western Mediterranean basin, which implies an ancient origin for the species. To test this hypothesis, we obtained a large number of samples from across its distribution area. Using known and new molecular markers and, for the first time in planarians, a molecular clock, we analysed the genetic variability and demographic parameters within the species and between its sexual and asexual populations to estimate when they diverged. Results A total of 2 kb from three markers (COI, CYB and a nuclear intron N13 was amplified from ~200 specimens. Molecular data clustered the studied populations into three groups that correspond to the west, central and southeastern geographical locations of the current distribution of S. mediterranea. Mitochondrial genes show low haplotype and nucleotide diversity within populations but demonstrate higher values when all individuals are considered. The nuclear marker shows higher values of genetic diversity than the mitochondrial genes at the population level, but asexual populations present lower variability than the sexual ones. Neutrality tests are significant for some populations. Phylogenetic and dating analyses show the three groups to be monophyletic, with the west group being the basal group. The time when the diversification of the species occurred is between ~20 and ~4 mya, although the asexual nature of the western populations could have affected the dating analyses. Conclusions S. mediterranea is an old species that is sparsely distributed in a harsh habitat

  17. A new species of Temnocephala (Platyhelminthes, Temnocephalida commensal of Pomella megastoma (Mollusca, Ampullariidae from Misiones, Argentina Una especie nueva de Temnocephala (Platyhelminthes, Temnocephalida comensal de Pomella megastoma (Mollusca, Ampullariidae de Misiones, Argentina

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    Cristina Damborenea

    2008-08-01

    Full Text Available Temnocephala lamothei n. sp., a commensal of Pomella megastoma (Sowerby, 1825, is described herein from specimens collected at Arroyo Yabotí-Miní (Misiones province, Argentina. Juveniles and adults were removed from the mantle cavity by host relaxation. Distinctive characters of the new species are: non-partitioned intestine; conical cirrus with 1 face flat and another concave; distal area with spines, as evidenced by a strong, oblique sclerotized ring, and 2 rows of long spines, an internal one with long spines arising from base of introvert and an external one arising from distal end of the introvert. The closest species are T. iheringi, T. rochensis and T. haswelli, which are also commensals of mollusc species. The presence of this new species of Temnocephala, and its similarity to the other species that are commensals of molluscan species, suggest the existence of a morphologically homogeneous group.Temnocephala lamothei n. sp., comensal de Pomella megastoma (Sowerby, 1825, se describe para el arroyo Yabotí-Miní, provincia de Misiones, Argentina. Se extrajeron ejemplares juveniles y adultos de la cavidad paleal, por relajación de los hospederos. Las características distintivas de la nueva especie son: intestino no septado, cirro de forma cónica, con una cara plana y otra cóncava, zona distal con espinas evidente por un fuerte anillo oblicuo esclerosado. Dos hileras de espinas se reconocen en el extremo distal, 1 interna de espinas largas, que surge desde la base del introverso, y 1 externa, que surge del extremo distal del mismo. Las especies más semejantes son T. iheringi, T. rochensis y T. haswelli, especies comensales de moluscos con las que es comparada. El hallazgo de esta nueva especie de Temnocephala y sus características semejantes a las restantes especies del género comensales de moluscos, sugieren que las especies conocidas hasta la fecha formen un grupo morfológicamente homogéneo.

  18. Three new species of Monogenea (Platyhelminthes parasites of fish in the Guandu river, southeastern Brazil=Três novas espécies de Monogenea (Platyhelminthes parasitos de peixes do rio Guandu, Sudeste do Brasil

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    José Luis Fernando Luque

    2012-10-01

    Full Text Available Current essay describes three new Monogenean species, namely, Cosmetocleithrum striatuli sp. nov., Jainus leporini sp. nov. and Rhabdosynochus guanduensis sp. nov., parasites on the gills of Trachelyopterus striatulus (Steindachner, 1877, Leporinus copelandii Steindachner, 1875 and Centropomus undecimalis (Bloch, 1792, respectively. Fish were collected from the Guandu river, State of Rio de Janeiro, Brazil between August 2005 and November 2008. Cosmetocleithrum striatuli sp. nov. differs from all other congeneric species by the shape of an accessory piece (more robust and resembling a crustacean claw or chela and by the shape of its ventral and dorsal bars (not V-shaped and with expanded lateral ends directed to the rear. Jainus leporini sp. nov. differs from all other Jainus species by the male copulation organ (MCO, with a 2-ring coil, by the absence of medial projection on ventral bar and by a plate-like sclerotized structure associated to the vagina. Rhabdosynochus guanduensis sp. nov. differs from all other congeneric species by the morphology of the copulation complex and by a shell-shaped vagina.Três novas espécies, Cosmetocleithrum striatuli sp. nov., Jainus leporini sp. nov. e Rhabdosynochus guanduensis sp. nov., parasitando as brânquias de Trachelyopterus striatulus (Steindachner, 1877, Leporinus copelandii Steindachner, 1875 e Centropomus undecimalis (Bloch, 1792, respectivamente, são descritas no presente trabalho. Os peixes foram coletados do rio Guandu, Estado do Rio de Janeiro, Brasil, no período de agosto de 2005 a novembro de 2008. Cosmetocleithrum striatuli sp. nov. difere de todas as outras espécies congenéricas pelo formato da pesca acessória (muito robusta e semelhante a uma quela de crustáceo e pelo formato das barras ventral e dorsal (sem o formato de V e com as extremidades laterais expandidas e direcionadas posteriormente. Jainus leporini sp. nov. difere de todas as outras espécies do gênero pelo órgão copulatório masculino (OCM ter duas voltas de diâmetro do anel, pela ausência de projeção medial na barra ventral e por possuir uma vagina associada a uma estrutura esclerotizada em forma de placa. Rhabdosynochus guanduensis sp. nov. difere de todas as outras espécies congenéricas pela morfologia do complexo copulatório e pela vagina em forma de concha.

  19. Development of mitochondrial loop-mediated isothermal amplification for detection of the small liver fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes).

    Science.gov (United States)

    Le, Thanh Hoa; Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-04-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10(-4) ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis.

  20. The invasive land planarian Platydemus manokwari (Platyhelminthes, Geoplanidae: records from six new localities, including the first in the USA

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    Jean-Lou Justine

    2015-06-01

    Full Text Available The land planarian Platydemus manokwari de Beauchamp, 1963 or “New Guinea flatworm” is a highly invasive species, mainly in the Pacific area, and recently in Europe (France. We report specimens from six additional countries and territories: New Caledonia (including mainland and two of the Loyalty Islands, Lifou and Maré, Wallis and Futuna Islands, Singapore, Solomon Islands, Puerto Rico, and Florida, USA. We analysed the COI gene (barcoding in these specimens with two sets of primers and obtained 909 bp long sequences. In addition, specimens collected in Townsville (Australia were also sequenced. Two haplotypes of the COI sequence, differing by 3.7%, were detected: the “World haplotype” found in France, New Caledonia, French Polynesia, Singapore, Florida and Puerto Rico; and the “Australian haplotype” found in Australia. The only locality with both haplotypes was in the Solomon Islands. The country of origin of Platydemus manokwari is New Guinea, and Australia and the Solomon Islands are the countries closest to New Guinea from which we had specimens. These results suggest that two haplotypes exist in the area of origin of the species, but that only one of the two haplotypes (the “World haplotype” has, through human agency, been widely dispersed. However, since P. manokwari is now recorded from 22 countries in the world and we have genetic information from only 8 of these, with none from New Guinea, this analysis provides only partial knowledge of the genetic structure of the invasive species. Morphological analysis of specimens from both haplotypes has shown some differences in ratio of the genital structures but did not allow us to interpret the haplotypes as different species. The new reports from Florida and Puerto Rico are firsts for the USA, for the American continent, and the Caribbean. P. manokwari is a known threat for endemic terrestrial molluscs and its presence is a matter of concern. While most of the infected territories reported until now were islands, the newly reported presence of the species in mainland US in Florida should be considered a potential major threat to the whole US and even the Americas.

  1. A comprehensive molecular phylogeny of dalytyphloplanida (platyhelminthes: rhabdocoela reveals multiple escapes from the marine environment and origins of symbiotic relationships.

    Directory of Open Access Journals (Sweden)

    Niels Van Steenkiste

    Full Text Available In this study we elaborate the phylogeny of Dalytyphloplanida based on complete 18S rDNA (156 sequences and partial 28S rDNA (125 sequences, using a Maximum Likelihood and a Bayesian Inference approach, in order to investigate the origin of a limnic or limnoterrestrial and of a symbiotic lifestyle in this large group of rhabditophoran flatworms. The results of our phylogenetic analyses and ancestral state reconstructions indicate that dalytyphloplanids have their origin in the marine environment and that there was one highly successful invasion of the freshwater environment, leading to a large radiation of limnic and limnoterrestrial dalytyphloplanids. This monophyletic freshwater clade, Limnotyphloplanida, comprises the taxa Dalyelliidae, Temnocephalida, and most Typhloplanidae. Temnocephalida can be considered ectosymbiotic Dalyelliidae as they are embedded within this group. Secondary returns to brackish water and marine environments occurred relatively frequently in several dalyeliid and typhloplanid taxa. Our phylogenies also show that, apart from the Limnotyphloplanida, there have been only few independent invasions of the limnic environment, and apparently these were not followed by spectacular speciation events. The distinct phylogenetic positions of the symbiotic taxa also suggest multiple origins of commensal and parasitic life strategies within Dalytyphloplanida. The previously established higher-level dalytyphloplanid clades are confirmed in our topologies, but many of the traditional families are not monophyletic. Alternative hypothesis testing constraining the monophyly of these families in the topologies and using the approximately unbiased test, also statistically rejects their monophyly.

  2. On the systematic position of Collyricloides massanae Vaucher, 1969 (Platyhelminthes: Digenea) with notes on distribution of this trematode species.

    Science.gov (United States)

    Kanarek, Gerard; Zaleśny, Grzegorz; Czujkowska, Agnieszka; Sitko, Jiljí; Harris, Philip D

    2015-04-01

    The systematic position of the Collyricloides massanae, a rare cyst-dwelling parasite, located on intestinal wall of European birds and rodents, have always been controversial. Based on newly obtained sequences of the 28 sDNA of C. massanae from avian and rodent host from Central Europe, and on the previously published sequences of several genera and families among Microphalloidea, we evaluate its taxonomic position and the phylogenetic relationships within the genera Collyriclum Kossack, 1911 and Collyricloides Vaucher, 1969 which form the family Collyriclidae Ward, 1917. In the cladogram, C. massanae appears among the Pleurogenidae, forming a clade with Gyrabascus amphoraeformis (Modlinger, 1930) and Cortrema magnicaudata (Bykhovskaya-Pavlovskaya, 1950). We reject the commonly accepted placement of Collyricloides as the sister genus to Collyriclum within the Collyriclidae. Besides, we present and discuss the unusual records of C. massanae in the bank vole Myodes glareolus from northeastern Poland. PMID:25638231

  3. Taenia saginata Goeze, 1872 (Platyhelminthes: Cestoda: Taeniidae) from an indigenous native from Tierra del Fuego, Chile

    OpenAIRE

    Eduardo I. Faúndez; Máriom A. Carvajal

    2015-01-01

    First record of Taenia saginata from an indigenous from Tierra del Fuego (Chilean Patagonia) is reported, from museum material of the year 1902. The importance of the record is discussed. Illustrations of the specimen are given.

  4. Light and electron microscopy observations of embryogenesis and egg development in the human liver fluke, Opisthorchis viverrini (Platyhelminthes, Digenea).

    Science.gov (United States)

    Khampoosa, Panita; Jones, Malcolm K; Lovas, Erica M; Srisawangwong, Tuanchai; Laha, Thewarach; Piratae, Supawadee; Thammasiri, Chalida; Suwannatrai, Apiporn; Sripanidkulchai, Bungorn; Eursitthichai, Veerachai; Tesana, Smarn

    2012-02-01

    Eggs of most species digenean flukes hatch in the external environment to liberate larvae that seek and penetrate a snail intermediate host. Those of the human liver flukes, Opisthorchis viverrini, hatch within the gastrointestinal canal of their snail hosts. While adult parasites are primarily responsible for the pathology in cases of human opisthorchiasis, their eggs also contribute by inducing granulomata and in serving as nidi for gallstone formation. In view of the peculiar biology of O. viverrini eggs and their contribution to pathology, we investigated embryogenesis in this species by light and transmission electron microscopy. Egg development was traced from earliest stages of coalescence in the ootype until full embryonation in the distal region of the uterus. Fully mature eggs were generally impermeable to resin and could not be examined by conventional electron microscopy methods. However, the use of high-pressure freezing and freeze-substitution fixation of previously fixed eggs enabled the internal structure of mature eggs, particularly the subshell envelopes, to be elucidated. Fertilization occurs in the ootype, and the large zygote is seen therein with a single spermatozoon wrapped around its plasma membrane. As the zygote begins to divide, the spent vitellocytes are pushed to the periphery of the eggs, where they progressively degrade. The early eggshell is formed in the ootype by coalescing eggshell precursor material released by approximately six vitelline cells. The early eggs have a thinner eggshell and are larger than, but lack the characteristic shape of, mature eggs. Characteristic shell ornamentation, the "muskmelon" appearance of eggs, appears after eggshell polymerization in the ootype. Pores are not present in the shell of O. viverrini eggs. The inner and outer envelopes are poorly formed in this species, with the outer envelope evident beneath the eggshell at the opercular pole of the mature egg. The miracidium has a conical anterior end that lacks the distinctive lamellar appearance of the terebratorium of other digeneans, such as the schistosomes. The miracidium is richly glandular, containing an apical gland in the anterior end, large cephalic gland, and posterior secretory glands. Each gland contains a secretory product with different structure. The paucity of vitelline cells associating with eggs, the reduced size of eggs, and reduced complexity of the extraembryonic envelopes are interpreted as adaptations to the peculiar hatching biology of the miracidia. PMID:21786067

  5. New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on Aegla serrana Buckup & Rossi (Crustacea, Anomura from southern Brazil

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    José Felipe Ribeiro Amato

    2003-09-01

    Full Text Available A new species of the genus Temnocephala Blanchard, 1849 is described from southern Brazil, ectosymbiont on Aegla serrana Buckup & Rossi, 1977, an anomuran crustacean, collected in a creek and a reservoir of the highlands in the State of Rio Grande do Sul. All crustaceans examined were positive for this species of Temnocephala and carried eggs in different regions of the ventral side: perioral area, pleural strips, esternal plates, pereiopods and chelipods; to a lesser extent in the dorsal side of the cephalothorax and dorsal side of the uropods; as well as adult and young specimens. The most distinctive characters of the new species are: 1 cyanophilous glands forming an irregular-shaped, grape-like, bunch of approximately 10-15 cells, deeply staining with hematoxylin; 2 shape and size of the cirrus and its introvert section; 3 number, size and distribution of the rhabdite glands and 4 shape and position of the post tentacular, 'excretory' syncytial plates, with the off-centered nephridiopore.

  6. The complete mitochondrial genome of Neobenedenia melleni (Platyhelminthes: Monogenea): mitochondrial gene content, arrangement and composition compared with two Benedenia species.

    Science.gov (United States)

    Zhang, Juan; Wu, Xiangyun; Li, Yanwei; Zhao, Mengwei; Xie, Mingquan; Li, Anxing

    2014-10-01

    The complete mitochondrial (mt) genome sequences of Neobenedenia melleni were determined and compared with those of Benedenia seriolae and B. hoshinai. This circular genome comprises 13,270 bp and includes all 36 typical mt genes found in flatworms. Total AT content of N. melleni is 75.9 %. ATG is the most common start codon, while nad4L is initiated by GTG. All protein-coding genes are predicted to terminate with TAG and TAA. N. melleni has the trnR with a TCG anticodon, which is the same to B. seriolae but different from B. hoshinai (ACG). The mt gene arrangement of N. melleni is similar to that of B. seriolae and B. hoshinai with the exception of three translocations (trnF, trnT and trnG). The overlapped region between nad4L and nad4 was found in the N. melleni mt genome, which was also reported for the published Gyrodactylus species, but it was not found in those of B. seriolae and B. hoshinai, which are non-coding regions instead. The present study provides useful molecular characters for species or strain identification and systematic studies of this parasite. PMID:25024046

  7. A new and alien species of ``oyster leech'' (Platyhelminthes, Polycladida, Stylochidae) from the brackish North Sea Canal, The Netherlands

    Science.gov (United States)

    Sluys, Ronald; Faubel, Anno; Rajagopal, Sanjeevi; Velde, Gerard Van Der

    2005-11-01

    A new species of polyclad flatworm, Imogine necopinata Sluys, sp. nov., is described from a brackish habitat in The Netherlands. Taxonomic affinities with Asian species and the ecology of the animals suggest that the species is an introduced, exotic component of the Dutch fauna. The new species belongs to a group of worms with species that are known to predate on oysters.

  8. Spot the difference: Two cryptic species of Gyrodactylus von Nordmann, 1832 (Platyhelminthes: Monogenea) infecting Astyanax aeneus (Actinopterygii, Characidae) in Mexico.

    Science.gov (United States)

    Razo-Mendivil, Ulises; García-Vásquez, Adriana; Rubio-Godoy, Miguel

    2016-10-01

    Over the course of one year, undescribed specimens of Gyrodactylus were recovered from banded tetra, Astyanax aeneus collected in the La Antigua and Nautla river basins in central Veracruz, Mexico. Parasites were processed for morphometric and molecular analyses. Morphometrically, Gyrodactylus samples collected in the La Antigua river had slightly smaller haptoral structures than those collected from the Nautla river. During the 12month-collection of samples, however, water temperature varied considerably (ca. 20°C to 30°C), and this abiotic factor is known to affect the size of gyrodactylid attachment structures. Moreover, no clear discrimination was possible between individual parasites collected from the two rivers based on the morphology of the marginal hook, which is recognised as a very informative character to discriminate between species. The morphology of the ventral bar, however, differed between specimens from both rivers: worms from Nautla all had long, rounded processes on the ventral bar, which formed a relatively closed angle with the dorsal edge of the bar proper, while most - but not all - specimens from La Antigua had comparatively slender processes forming a more open angle with respect to the ventral bar. Phylogenetic analyses based on the sequences of the ITS1, 5.8S rRNA gene, and ITS2 of gyrodactylids indicated the existence of two distinct, well-supported lineages whose sequences differ by >4%, one of which was only found in the Nautla basin, while the other was collected in both river systems. A posteriori, principal component analysis (PCA) of the morphometric data of sequenced specimens indicated that features of the dorsal bar, the hamuli and the ventral bar enable discrimination between the two phylogenetic lineages. Based on these independent sources of information (morphometric and molecular data), two new species of Gyrodactylus are described: Gyrodactyluspakan n. sp. and Gyrodactylusteken n. sp. The phylogenetic relationships of both new species to other gyrodactylids infecting characiformes (for which molecular data are available) are presented, which suggests that their closest relative is Gyrodactylus carolinae, a parasite of Characidium lanei in Brazil. PMID:27208885

  9. A polyphasic approach to the taxonomy of the Alternaria infectoria species-group

    DEFF Research Database (Denmark)

    Andersen, Birgitte; Sørensen, Jens Laurids; Nielsen, Kristian Fog;

    2009-01-01

    morphologically identifiable as belonging to the A. infectoria species-group together with 12 strains belonging to closely related species: Alternaria malorum (syn. Cladosporium malorum), Chalastospora cetera (syn. Alternaria cetera) and Embellisia abundans. Morphological examination separated the 51 strains...

  10. Seussapex, a new genus of lecanicephalidean tapeworm (Platyhelminthes: Cestoda) from the stingray genus Himantura (Myliobatiformes: Dasyatidae) in the Indo-West Pacific with investigation of mode of attachment.

    Science.gov (United States)

    Jensen, Kirsten; Russell, Shelbi L

    2014-06-01

    A new lecanicephalidean genus, Seussapex gen. n., is erected for specimens collected from stingrays from the Indo-West Pacific resembling the little known species Tenia [sic] narinari MacCallum, 1917 from the spotted eagle ray, Aetobatus narinari (Euphrasen). Members of this new genus are unique in their possession of a multi-tiered apical structure comprising a bipartite apical modification of the scolex proper, and an externally bipartite apical organ with anterior and posterior glandular compartments internally. The appearance of the scolex varies dramatically depending on state of protrusion and/or evagination of these different parts which appear to be able to function independently. Seussapex karybares sp. n. parasitizing Himantura uarnak 2 (sensu Naylor et al., 2012) in northern Australia is described as the type species and Tenia [sic] narinari is transferred to the new genus. The two species differ in scolex length and width of the posterior dome-shaped portion of the apical organ. Histological sections of scoleces stained using the periodic acid-Schiff(PAS) reaction showed the surface of the anterior part of the apical organ and the anterior glandular compartment to stain PAS positive, suggesting a chemical mode of attachment to the host's intestinal mucosal surface. Extensive collecting efforts of stingrays in the Indo-West Pacific shows Seussapex gen. n. to be restricted to species of Himantura Miller et Henle and suggests additional diversity in this group of hosts. In addition, the host identity of Seussapex narinari (MacCallum, 1917) comb. n. is called into question.

  11. Towards a phylogeny of the Metazoa: evaluating alternative phylogenetic positions of Platyhelminthes, Nemertea, and Gnathostomulida, with a critical reappraisal of cladistic characters

    NARCIS (Netherlands)

    Jenner, Ronald A.

    2004-01-01

    This paper critically assesses all morphological cladistic analyses of the Metazoa that were published during the last one and a half decades. Molecular and total evidence analyses are also critically reviewed. This study focuses on evaluating alternative phylogenetic positions of the ‘acoelomate’ w

  12. First report of the genus Cratera (Platyhelminthes, Geoplanidae) in Argentina, with description of a new species and comments on the species of the genus

    Science.gov (United States)

    Negrete, Lisandro; Brusa, Francisco

    2016-01-01

    Abstract A new species of land planarians of the genus Cratera is described. Cratera viridimaculata sp. n. was recorded in the Atlantic Forest Ecoregion, in north-eastern Argentina, and represents the first report of the genus Cratera outside Brazil. The new species is about 50 mm in length and externally characterized by a color pattern consisting of a light green olive pigmentation on the dorsum, stippled with dark gray fine spots, and dorsal eyes. Other features regarding the internal anatomy are the presence of a glandular margin, Cutaneous Muscular Index (CMI) of 10–13%, pharynx cylindrical, prostatic vesicle extrabulbar, tubular and C-shaped, with a proximal bifurcated portion, penis papilla protrusible with ejaculatory duct widened in its distal portion, and female atrium funnel-shaped. The new species is compared and discussed with its congeners. PMID:27587974

  13. Species of Gyrodactylus von Nordmann, 1832 (Platyhelminthes: Monogenea) from cichlids from Zambezi and Limpopo river basins in Zimbabwe and South Africa: evidence for unexplored species richness.

    Science.gov (United States)

    Zahradníčková, Petra; Barson, Maxwell; Luus-Powell, Wilmien J; Přikrylová, Iva

    2016-09-01

    New findings on Gyrodactylus spp. parasitising African cichlids in southern Africa are presented, comprising data from Zimbabwe and South Africa. Morphometry of opisthaptoral hard parts in combination with nuclear ribosomal DNA sequences confirmed the presence of six species of Gyrodactylus von Nordmann, 1832. Three new species are described from fishes in Zimbabwe: Gyrodactylus chitandiri n. sp. from the gill arches of Coptodon rendalli (Boulenger) and Pseudocrenilabrus philander (Weber); Gyrodactylus occupatus n. sp. from the fins of Oreochromis niloticus (L.), Pharyngochromis acuticeps (Steindachner) and P. philander; and Gyrodactylus parisellei n. sp. from the fins of O. niloticus, P. philander and Tilapia sp. Gyrodactylus nyanzae Paperna, 1973 was also identified from the gills of O. niloticus and C. rendalli collected from two localities in Zimbabwe; these findings represent new host and locality records for this parasite. Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011 was identified from P. philander collected in South Africa and Zimbabwe thereby providing new host and locality records for this parasite. Finally, Gyrodactylus yacatli García-Vásquez, Hansen, Christison, Bron & Shinn, 2011 was collected from the fins of O. niloticus and P. philander studied in Zimbabwe; this represents the first record of this species from the continent of Africa. Notably, this study improves upon the knowledge of Gyrodactylus spp. parasitising cichlids from these southern African regions. All species studied were recorded from at least two different cichlid host species indicating trend for a wide range of Gyrodactylus hosts in Africa. Accordingly, this supports the idea of intensive host switching in the course of their evolution. PMID:27522367

  14. The description of Gyrodactylus corleonis sp. n. and G. neretum sp. n. (Platyhelminthes: Monogenea) with comments on other gyrodactylids parasitising pipefish (Pisces: Syngnathidae).

    Science.gov (United States)

    Paladini, Giuseppe; Cable, Joanne; Fioravanti, Maria Letizia; Faria, Patricia J; Shinn, Andrew P

    2010-03-01

    The current work describes two new species of Gyrodactylus von Nordmann, 1832 collected from pipefish Syngnathus scovelli (Evermann et Kendall) and Syngnathus typhle L. during two separate gyrodactylosis episodes on fish held in a public aquarium located in northern Italy. The gyrodactylids collected from the skin, fins and gills of pipefish were subjected to a morphological analysis of the attachment hooks and the morphometric data were compared to the four species of Gyrodactylus previously described from syngnathid hosts, namely G. eyipayipi Vaughan, Christison, Hansen et Shinn, 2010, G. pisculentui Williams, Kritsky, Dunnigan, Lash et Klein, 2008, G. shorti Holliman, 1963 and G. syngnathi Appleby, 1996. Principal components analysis (PCA) of the morphological data indicated six clusters; two discrete groups among the specimens taken from the pipefisli held in the Italian aquarium and four further groups representing G. eyipayipi, G. pisculentus, G. shorti and G. syngnathi. Molecular sequences of the ribosomal internal transcribed spacers (ITS1 and ITS2) and the 5.8S gene for the new species considered here were then compared with those available for other species in GenBank. The comparison did not reveal any identical match, supporting the morphological analysis that Gyrodactylus corleonis sp. n. from S. typhle and Gyrodactylus neretum sp. n. from S. scovelli represent distinct species. Both G. corleonis and G. neretum possess robust hamuli, marginal hook blades that curve smoothly from their sickle base to a point beyond the toe and, ventral bars with a broad median portion and a reduced membrane. Gyrodactylus corleonis, however, can be distinguished on the basis of its heart-shaped ventral bar; G. neretum has a 1:2 hamulus point:shaft ratio and a rectangular-shaped ventral bar. A redescription of the haptoral hard parts of the four species previously recorded on pipefish is also presented. PMID:20449996

  15. Endoparasitos (Nemathelminthes y Platyhelminthes de animales de vida silvestre de la Reserva de Biósfera del Manu, Perú

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    Manuel Tantaleán

    2013-06-01

    Full Text Available Durante el año 2001, se recolectaron 8 géneros de helmintos de mamíferos y aves silvestres del Perú, en la Reserva Biosfera del Manu (Departamentos de Cusco y Madre de Dios, desde los 470 a 3780 m. Los parásitos fueron fijados con alcohol etílico en el campo y transportados al laboratorio para estudiarlos; los nemátodos se diafanizaron y los céstodos y tremátodos se colorearon con carmín de acuerdo a técnicas convencionales. La identificación específica de algunos helmintos fue imposible por el estado en que se encontraban, pero se dan a conocer por ser material de gran importancia y ser algunos de ellos algunos registros nuevos para el Perú. Nuestros hallazgos son los siguientes: Rhopalias caballeroi Kifune y Uyema, 1982, Rhopalias sp. (probable n. sp., Taenia pisiformis Bloch, 1780 (cisticerco, Mesocestoides sp. (tetratyridia, Aprocta sp., Evaginuris branicki Mc Clure, 1932, Haematospiculum sp., Protospirura sp., Diplotriaena sp., Thelazia sp. 1, Thelazia sp. 2, Thelazia sp. 3 y Subulura sp.

  16. A new species of Unilatus (Platyhelminthes: Monogenoidea) from the gills of Leporacanthicus galaxias Isbrücker et Nijssen (Siluriformes: Loricariidae) from Brazil.

    Science.gov (United States)

    Branches, Bárbara; Domingues, Marcus V

    2014-03-01

    Unilatus irae sp. nov. (Dactylogyridae) is described from the gills of the armored catfish, Leporacanthicus galaxias Isbrücker et Nijssen (Loricariidae: Ancistrinae), from Guamá river, Pará State, Brazil. The new species can be differentiated from its cogeneners by the combination of the following features: anterior anchor with well-developed superficial root, inconspicuous deep root, shaft bent at midpoint, forming angle of approximately 60°, evenly short curved point; posterior anchor with inconspicuous roots, sclerotized cap of base with small protuberance for articulation to posterior bar; evenly curved shaft and short point; anterior bar broadly V-shaped, with small posteromedial projection; and posterior bar anteriorly expanded on it midportion, with expanded ends slightly curved in posterior direction. PMID:24570054

  17. Assessment of platyhelminth diversity within amphibians of French Guiana revealed a new species of Nanopolystoma (Monogenea: Polystomatidae) in the caecilian Typhlonectes compressicauda

    OpenAIRE

    du Preez, Louis H.; Badets, Mathieu; Verneau, Olivier

    2014-01-01

    Scientists attending the First World Congress of Her-petology in 1989 first became concerned about a widespread decline in amphibian population numbers (Stuart et al. 2004). Since then, the number of studies and publications on amphibians increased considerably and the number of species known nearly doubled to the current figure of 7 044 (Frost 2013). In their comprehensive study to identify biodiversity hotspots for conservation priorities , Meyers et al. (2000) reported on the unique biodiv...

  18. Stenostomum cf. leucops (Platyhelminthes in Thailand: a surface observation using scanning electron microscopy and phylogenetic analysis based on 18S ribosomal DNA sequences

    Directory of Open Access Journals (Sweden)

    Arin Ngamniyom

    2016-02-01

    Full Text Available The genus Stenostomum contains small turbellaria that are widely distributed in freshwater environments worldwide. However, there are only rare reports or studies of this genus from Thailand. Therefore, the objective of this study was to report S. cf. leucops in Thailand collected from Pathum Thani Province. The worm morphology and surface topography using scanning electron microscopy were determined. Moreover, the phylogenetic tree of S. cf. leucops was analysed with 17 flatworms based on the 18S ribosomal DNA sequences. The phylogenetic relationship shared a common ancestry of Catenulida species, and S. cf. leucops displayed a monophyletic pattern within Stenostomum spp. The results of the morphological and molecular data are discussed. These results may increase the knowledge of freshwater microturbellarians in Thailand.

  19. Nanoporous Structures Similar to Those Reported from Squid Sucker Teeth are also Present in Egg Shells of a Terrestrial Flatworm (Platyhelminthes; Rhabditophora; Geoplanidae) from Hachijojima (Izu Islands, Japan).

    Science.gov (United States)

    Meyer-Rochow, Victor Benno; Miinalainen, Ilkka

    2016-07-01

    Shells of the egg cocoon of a terrestrial planarian (Diversibipalium sp.) from Hachijojima were found to be composed of a lattice of parallel nanotubes of ca. 120 nm diameter oriented perpendicular to the shell's surface. The arrangement of the porous proteinaceous tubes closely resembles that has recently been reported from the sucker teeth of squid and to date is the only other example of this kind of structure. Although the array of nanotubes undoubtedly contributes to the stiffness of the shell and helps protecting the embryo, questions such as to how the planary worm produces the array of nanotubes and what exactly their chemical and physical properties are versus those of the squid sucker tooth still remain to be answered. PMID:27278842

  20. First report of Temnocephala haswelli (Platyhelminthes: Temnocephalida in Pomacea canaliculata (Mollusca: Ampullariidae from Brazil: description update based on specimens from the state of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Samantha A. Seixas

    2010-06-01

    Full Text Available The impact of the discovery of Temnocephala haswelli Ponce de Léon, 1989, described as ectosymbionts of ampullariid apple snails outside of Uruguay, motivated us to collect a large number of specimens of Pomacea canaliculata (Lamarck, 1822 from several localities in the southern portion of the state of Rio Grande do Sul. This species was recorded three times after its description: in a study of chromosomes, in a study about the ultrastructure of the collar receptor cells, and in a study of the Haswell glands, all conducted in Uruguay. A total of 301 specimens of P. canaliculata were collected from 1999 to 2007. Temnocephalans found in the pallial cavity were identified as T. haswelli, which occurred in single infestations or concurrently with Temnocephala iheringi Haswell, 1893. Helminths usually showed a light-orange body pigmentation and conspicuous, intense red-eye pigment. Many taxonomic characters evidenced by several techniques were documented photographically for the first time. The typical curved cirrus, approximately 90°, typical of the species, showed some variation in the width of the shaft base, whereas the first longitudinal row of spines of the introvert appeared with shorter spines. The vagina was found to be thick-walled, but not very muscular, and to have a single, large and slightly asymmetrical sphincter, with the posterior portion of slightly larger diameter. Eggs were observed in the umbilicus and along the suture, but predominantly in the body whorl of the shell. Egg peduncles were found to be very short or, most of the time, the eggs were sessile, always with a long apical filament. The rounded shape of the dorsolateral 'excretory' syncytial epidermal plates had external margins reaching the ventrolateral region of the body and eccentric nephridiopores. This is the first record of the species outside Uruguay and in Brazil.

  1. New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida) ectosymbiont on giant water bugs, Belostoma spp. (Hemiptera, Belostomatidae) from southern Brazil Nova espécie do gênero Temnocephala Blanchard (Platyhelminthes, Temnocephalida) ectosimbionte sobre baratas d´água, Belostoma spp. (Hemiptera, Belostomatidae) da região sul do Brasil

    OpenAIRE

    José F. R. Amato; Suzana B. Amato

    2005-01-01

    A new species of Temnocephala Blanchard, 1849 is described from southern Brazil, ectosymbiont on giant water bugs (aquatic hemipterans), Belostoma spp. from the greater Porto Alegre, State of Rio Grande do Sul. Some hemipterans examined were positive for this species of Temnocephala and carried bunches of eggs between the first two pairs of legs and between the first pair of legs and the rostrum, as well as adult and young specimens. The adults were darkly pigmented (greenish-brown), mimetizi...

  2. A new species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on creeping water bugs, Cryphocricos granulosus De Carlo (Hemiptera, Naucoridae from southern Brazil Nova espécie de Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosimbionte sobre naucorídeos, Cryphocricos granulosus De Carlo (Hemiptera, Naucoridae da região Sul do Brasil

    Directory of Open Access Journals (Sweden)

    José F. R. Amato

    2007-12-01

    Full Text Available Temnocephala minutocirrus sp. nov., an ectosymbiont on Cryphocricos granulosus De Carlo, 1967, is described from the State of Rio Grande do Sul, southern Brazil. One hundred and nine naucorids were examined, of which 36 (33% were positive for this species of Temnocephala Blanchard, 1849. In one sample of 94 creeping water bugs, 49 (52% were 4th instar nymphs, 6% of which were infested; 45 (48% were adults, either brachypterous (40 with 18 males and 22 females or macropterous (5 with 1 male and 4 females, 67% of which were infested (29% males and 38% females. Temnocephalan eggs were found both ventrally and dorsally: fixed on coxae, trochanters, and along the sternum between fore middle, and hind pairs of legs; basal of the abdominal area; and on the scutellum, clavus, and hemelytra. Juvenile and adult temnocephalans were always devoid of body pigmentation, and were found living on the ventral body surface, preferably over the sternum, between the middle and hind pairs of legs. The most distinctive features of this new species are: 1 unusually short cirrus, slightly curved, with introvert corresponding to 37% of its total length; 2 dorsolateral 'excretory' syncytial epidermal plates, elliptic, with excretory pore relatively equatorial, closer to inner limit of each plate; 3 two pairs of large disc gland cells (paranephrocytes? located centrally, just ahead of testes; 4 testes relatively large, but unequal in size, anterior pair smaller, always in the same zone, those of the same side, partially superposed; and (5 vagina with weak muscular wall and without muscular sphincters.Temnocephala minutocirrus sp. nov., ectosimbionte sobre Cryphocricos granulosus De Carlo, 1967, é descrita para o Estado do Rio Grande do Sul. Cento e nove naucorídeos foram examinados, dos quais 36 (33% estavam positivos para esta espécie do gênero Temnocephala Blanchard, 1849. Em uma amostra de 94 hemípteros, 49 (52% eram ninfas de 4º instar, das quais, 6% estavam infestadas; 45 (48% eram adultos, braquípteros 40 (18 machos e 22 fêmeas ou macrópteros 5 (1 macho e 4 fêmeas, 67% dos quais estavam infestados (29% machos e 38% fêmeas, para esta espécie de temnocefalídeo. Ovos dos temnocefalídeos estavam fixados na face ventral do hemíptero, sobre as coxas, trocânteres e esterno, entre o primeiro, segundo e terceiro pares de pernas e na face dorsal, sobre o escutelo, clavo e hemiélitros. Temnocefalídeos juvenis e adultos sempre se apresentaram sem pigmentação corporal. Os caracteres mais distintivos da nova espécie são: 1 cirro muito curto, levemente curvo, com o 'introvert' correspondendo a 37% do comprimento total; 2 placas dorsolaterais, sinciciais 'excretoras' elípticas, com poro excretor equatorial, próximo do limite interno da placa; 3 dois pares de 'grandes glândulas do disco' (paranefrócitos? centrais, imediatamente à frente dos testículos; 4 testículos relativamente grandes, mas desiguais em tamanho, par anterior menor, sempre na mesma zona, aqueles do mesmo lado, parcialmente sobrepostos; e 5 vagina com parede muscular fracamente desenvolvida e sem esfíncteres musculares.

  3. New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on giant water bugs, Belostoma spp. (Hemiptera, Belostomatidae from southern Brazil Nova espécie do gênero Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosimbionte sobre baratas d´água, Belostoma spp. (Hemiptera, Belostomatidae da região sul do Brasil

    Directory of Open Access Journals (Sweden)

    José F. R. Amato

    2005-03-01

    Full Text Available A new species of Temnocephala Blanchard, 1849 is described from southern Brazil, ectosymbiont on giant water bugs (aquatic hemipterans, Belostoma spp. from the greater Porto Alegre, State of Rio Grande do Sul. Some hemipterans examined were positive for this species of Temnocephala and carried bunches of eggs between the first two pairs of legs and between the first pair of legs and the rostrum, as well as adult and young specimens. The adults were darkly pigmented (greenish-brown, mimetizing the color of the hemipteran hosts. The new species is similar to Temnocephala decarloi Moretto, 1978, from Argentina, the only other species of Temnocephala from belostomatid hemipterans known to date, by having an extra long and curved cirrus, but differs by having the distal portion of the introvert not bent as a 'full-bent' smoking pipe-like, as the author depicted originally for T. decarloi.Uma nova espécie de Temnocephala Blanchard, 1849 é descrita para o sul do Brasil, ectosimbionte sobre baratas-d'água (hemípteros aquáticos, Belostoma spp. da região metropolitana de Porto Alegre, Estado do Rio Grande do Sul. Vários hemípteros examinados estavam positivos para esta espécie do gênero Temnocephala, inclusive com posturas sempre localizadas na face ventral entre os dois primeiros pares de apêndices locomotores, e entre o primeiro par de pernas e o rostro. Espécimes adultos e jovens de tamanhos variados também foram sempre encontrados na face ventral do hemíptero. Os vermes adultos eram pigmentados (marrom-esverdeado, mimetizando a cor do exoesqueleto de seus hospedeiros. A nova espécie é semelhante à Temnocephala decarloi Moretto, 1978, descrita da Argentina, única espécie conhecida do gênero já encontrada sobre hemípteros belostomatídeos, por ter um cirro extremamente longo e curvo, mas difere desta por ter a porção distal do 'introvert' sem a forma típica de um cachimbo ('full-bent' como ilustrada pelo autor na descrição original.

  4. A survey of the Echinoderm Associates of the North-East Atlantic area

    NARCIS (Netherlands)

    Barel, C.D.N.; Kramers, P.G.N.

    1977-01-01

    CONTENTS Introduction................... 3 Systematic list of associate records............. 6 Protozoa................... 7 Coelenterata.................. 31 Platyhelminthes................. 32 Mesozoa................... 41 Nematoda................... 42 Rotatoria................... 43 Entoprocta..

  5. New records of Cotylea (Polycladida, Platyhelminthes) from Lizard Island, Great Barrier Reef, Australia, with remarks on the distribution of the Pseudoceros Lang, 1884 and Pseudobiceros Faubel, 1984 species of the Indo-Pacific Marine Region.

    Science.gov (United States)

    Marquina, Daniel; Aguado, M Teresa; Noreña, Carolina

    2015-09-18

    In the present work eleven polyclad species of Lizard Island are studied. Seven of them are new records for this locality of the Australian coral reef and one is new to science, Lurymare clavocapitata n. sp. (Family Prosthiostomidae). The remaining recorded species belong to the genera Pseudoceros (P. bimarginatus, P. jebborum, P. stimpsoni, P. zebra, P. paralaticlavus and P. prudhoei) and Pseudobiceros (Pb. hancockanus, Pb. hymanae, Pb. flowersi and Pb. uniarborensis). Regardless of the different distribution patterns, all pseudocerotid species show brilliant colours, but similar internal morphology. Furthermore, differences in the form and size of the stylet are characteristic, because it is a sclerotic structure that is not affected during fixation. In Pseudoceros, the distance between the sucker and the female pore also differs among species. These features do not vary enough to be considered as diagnostic, but they provide information that can help to disentangle similarly coloured species complexes. A key of the genera Pseudoceros and Pseudobiceros of the Indo-Pacific region is provided, in order to facilitate the identification of species from this area.

  6. Dactylogyrids (Platyhelminthes: Monogenoidea) parasitizing butterfly fishes (Teleostei: Chaetodontidae) from the coral reefs of Palau, Moorea, Wallis, New Caledonia, and Australia: species of Euryhaliotrematoides n. gen. and Aliatrema n. gen.

    Science.gov (United States)

    Plaisance, Laetitia; Kritsky, Delane C

    2004-04-01

    Seven species of Euryhaliotrematoides n. gen. and 1 species of Aliatrema n. gen. (Monogenoidea; Dactylogyridae) are described and reported from the gills of 15 species of butterfly fishes (Chaetodontidae) from the coral reefs of Moorea (French Polynesia), Wallis (Wallis and Futuna), Heron and Lizard (Australia), Palau (Micronesia), and New Caledonia: Aliatrema cribbi n. sp. from Chaetodon auriga, Chaetodon lunula, Chaetodon trifasciatus, Chaetodon ulietensis, Chaetodon vagabundus, Forcipiger flavisissimus, and Heniochus chrysostomus; Euryhaliotrematoides annulocirrus n. comb. from C. auriga, C. lunula, and C. vagabundus; Euryhaliotrematoides aspistis n. sp. from C. auriga, Chaetodon citrinellus, C. lunula, Chaetodon reticulatus, C. ulietensis, and C. vagabundus; Euryhaliotrematoides berenguelae n. sp. from C. citrinellus, Chaetodon ornatissimus, and F. flavisissimus; Euryhaliotrematoides grandis n. comb. from C. auriga, C. citrinellus, Chaetodon ephippium, Chaetodon kleinii, Chaetodon lineolatus, C. lunula, C. ornatissimus, C. trifasciatus, C. vagabundus, and H. chrysostomus; Euryhaliotrematoides microphallus n. comb. from C. auriga, C. citrinellus, C. ephippium, C. kleinii, C. lunula, C. ornatissimus, C. reticulatus, Chaetodon trifascialis, C. trifasciatus, C. vagabundus, F. flavisissimus, and H. chrysostomus; Euryhaliotrematoides pirulum n. sp. from C. auriga, C. citrinellus, C. lunula, C. trifasciatus, and C. vagabundus; and Euryhaliotrematoides triangulovagina n. comb. from C. auriga, C. citrinellus, C. kleinii, C. lunula, C. ornatissimus, C. vagabundus, F. flavisissimus, H. chrysostomus, and Hemitaurichthys polylepis. All reports of previously described species are new locality records. With exceptions of E. grandis and E. annulocirrus on C. auriga and C. lunula and E. triangulovagina and E. microphallus on C. auriga, all reports are new host records. Haliotrema hainanensis and H. affinis are considered junior subjective synonyms of E. triangulovagina and E. annulocirrus, respectively. Aliatrema n. gen. is characterized by marine dactylogyrids with tandem gonads (germarium pretesticular), haptoral hooks with upright acute thumbs, a coiled copulatory organ with counterclockwise rings and funnel-shaped base but lacking an accessory piece, and a dextral vaginal pore. Euryhaliotrematoides n. gen. is characterized by marine dactylogyrids having tandem gonads (germarium pretesticular), haptoral hooks with upright acute thumbs, a coiled copulatory organ with counterclockwise rings and funnel-shaped base, a vas deferens looping the left intestinal cecum, and a dextral vaginal pore. PMID:15165056

  7. First report of gastrocotylinean post-oncomiracidia (Platyhelminthes: Monogenoidea: Heteronchoinea) on gills of flyingfish (Exocoetidae), snapper (Lutjanidae), dolphinfish (Coryphaenidae), and amberjack (Carangidae) from the Gulf of Mexico: decoy hosts and the dilution effect.

    Science.gov (United States)

    Kritsky, Delane C; Bullard, Stephen A; Bakenhaster, Micah D

    2011-09-01

    Larvae, identified as post-oncomiracidia of the suborder Gastrocotylinea (Monogenoidea), were collected from formalin-fixed gills excised from six species of marine fishes captured from the Gulf of Mexico off Mississippi and Florida: common dolphinfish, Coryphaena hippurus and pompano dolphinfish, Coryphaena equiselis (both Perciformes, Coryphaenidae); gray snapper, Lutjanus griseus (Perciformes, Lutjanidae); greater amberjack, Seriola dumerili (Perciformes, Carangidae); and Atlantic flyingfish, Cheilopogon melanurus and sailfin flyingfish, Parexocoetus hillianus (both Beloniformes and Exocoetidae). Based on a combination of diagnostic morphological features, the specimens were divided into two basic forms, each of which was further subdivided into two morphotypes. No gastrocotylinean post-oncomiracidium had been reported previously from these hosts. Of the six host species, only C. hippurus serves as a host (unconfirmed) for the adult of a gastrocotylinean species, suggesting that the recorded fishes from the Gulf of Mexico comprise dead-end hosts acting as decoys for the oncomiracidia. These comparatively non-susceptible "decoy hosts" apparently dilute the susceptible fish-host population and by intercepting infective larvae (oncomiracidia) decrease the abundance of parasites on their typical hosts. PMID:21497672

  8. A new species of Acanthocotyle Monticelli, 1888 (Platyhelminthes: Monogenea: Acanthocotylidae) from the ventral skin of the banded stingaree, Urolophus cruciatus (Lacépède, 1804), from Tasmania, Australia.

    Science.gov (United States)

    Kearn, Graham; Whittington, Ian; Chisholm, Leslie; Evans-Gowing, Richard

    2016-09-01

    Acanthocotyle urolophi sp. nov. is described from the skin of the banded stingaree, Urolophus cruciatus (Lacépède, 1804). This is the first acanthocotylid to be described from Australian waters. Acanthocotyle urolophi sp. nov. is distinguished from other species of Acanthocotyle by a combination of the number of vitelline follicles 38 (33-46) and the number of rows 35 (32-37) of sclerites on the pseudohaptor. In addition, Acanthocotyle urolophi sp. nov. has no germarial appendix and no uterine "arm". A uterine receptaculum seminis was not identified in whole mounts. There is no penis papilla and no penis sclerite associated with the male reproductive opening. A brief description of the larva is provided. The diagnosis of the Acanthocotylidae Price, 1936 is amended and we review the Allacanthocotylinae Yamaguti, 1963, Lophocotylinae Yamaguti, 1963 and Pseudacanthocotylinae Yamaguti, 1963. We deem that these subfamilies are invalid and that the family now comprises only the subfamily Acanthocotylinae and the genus Acanthocotyle. The validity of species previously assigned to the Acanthocotylidae (sensu Yamaguti, 1963) is discussed and a key to what we consider to be the valid species in the family is also provided. PMID:27447227

  9. Redescription of Temnocephala iheringi (Platyhelminthes: Temnocephalida based on specimens from Pomacea canaliculata (Mollusca: Ampullariidae of the state of Rio Grande do Sul, Brazil: the possible type host and type locality

    Directory of Open Access Journals (Sweden)

    Samantha A. Seixas

    2010-04-01

    Full Text Available The original description of Temnocephala iheringi Haswell, 1893 was based on specimens collected by Hermann von Ihering from undetermined ampullariid apple snails, which at that time were identified as Ampullaria sp., and sent to William H. Haswell, with the type locality simply indicated as Brazil. The type specimens studied by Haswell were not found in the scientific collections of Brazil, Europe or Australia, and should be considered lost. In 1941, Pereira & Cuocolo collected specimens from apple snails, identified as Pomacea lineata (Spix in Wagner, 1827, at two localities (Guaicurús and Salobra in the state of Mato Grosso do Sul, central Brazil. These specimens could not be located either and should, thus, be considered lost as well. Pomacea canaliculata (Lamarck, 1822, the main host of T. iheringi in southern Brazil, is known to have a geographical distribution that reaches Uruguay and 400 km beyond the province of Buenos Aires, Argentina. Three hundred and one mollusks were collected from 1999 to 2007. Temnocephalans found in the pallial cavity presented a greenish body pigmentation (adults and lacked eye pigment of any color, including the red-eye pigment, typical of Neotropical species of Temnocephala Blanchard, 1849; straight cirrus, with a thick band at base of the introvert' swelling; and a single, circular, asymmetric vaginal sphincter, wider in diameter in the posterior portion. As the species occurs concurrently with two other species, at least in P. canaliculata from Rio Grande do Sul, the eggs of T. iheringi could not be reliably distinguished. A redescription of the species is provided. A comparison of data from the present work with those of earlier papers published on T. iheringi from Argentina showed that the Argentinean specimens had the smallest measurements.

  10. Morphological and molecular description of eight new species of Gyrodactylus von Nordmann, 1832 (Platyhelminthes: Monogenea) from poeciliid fishes, collected in their natural distribution range in the Gulf of Mexico slope, Mexico.

    Science.gov (United States)

    García-Vásquez, Adriana; Razo-Mendivil, Ulises; Rubio-Godoy, Miguel

    2015-09-01

    Eight new species of Gyrodactylus are described from Poecilia mexicana, Poeciliopsis gracilis, Pseudoxiphophorus bimaculatus [syn. = Heterandria bimaculata], and Xiphophorus hellerii collected in the Nautla and La Antigua River Basins in Veracruz, and in the Tecolutla River Basin in Puebla, Mexico. Analyzing the morphology of the marginal hooks, Gyrodactylus pseudobullatarudis n. sp. and Gyrodactylus xtachuna n. sp. are both very similar to Gyrodactylus bullatarudis; Gyrodactylus takoke n. sp. resembles Gyrodactylus xalapensis; Gyrodactylus lhkahuili n. sp. is similar to Gyrodactylus jarocho; and both Gyrodactylus microdactylus n. sp. and Gyrodactylus actzu n. sp. are similar to Gyrodactylus poeciliae in that all three species possess extremely short shaft points. A hypothesis of the systematic relationships of the eight new Gyrodactylus species and some of the known gyrodactylids infecting poeciliids was constructed with sequences of the Internal Transcribed Spacers (ITS1 and ITS2) and the 5.8S ribosomal gene of the rRNA. Phylogenetic trees showed that the new and previously described species of Gyrodactylus infecting poeciliid fishes do not form a monophyletic assemblage. Trees also showed that the eight new species described morphologically correspond to well-supported monophyletic groups; and that morphologically similar species are also phylogenetically close. Additionally, we correct previous erroneous records of the presence of Gyrodactylus bullatarudis on wild Poecilia mexicana and Xiphophorus hellerii collected in Mexico, as re-examination of the original specimens indicated that these corresponded to Gyrodactylus pseudobullatarudis n. sp. (infecting Poecilia mexicana and Xiphophorus hellerii) and to Gyrodactylus xtachuna n. sp. (on Xiphophorus hellerii). Finally, given the widespread anthropogenic translocation of poeciliid fishes for the aquarium trade and mosquito control programs, as well as the existence of invasive, feral poeciliid populations worldwide, we discuss the possibility that gyrodactylid parasites could be introduced along with the fish hosts-this work provides taxonomic information to assess that possibility, as it describes parasites collected from poeciliid fishes within their native distribution range. PMID:26091759

  11. Aspectos ecológicos de Diplectanum piscinarius (Platyhelminthes, Monogenea parasita de brânquias de Plagioscion squamosissimus (Osteichthyes, Sciaenidae da plan. inund. Alto rio Paraná, B - DOI: 10.4025/actascibiolsci.v27i3.1279 Ecological aspects of Diplectanum piscinarius (Platyhelminthes, Monogenea parasite of gills of Plagioscion squamosissimus (Osteichthyes, Sciaenidae in the Upper Paraná River floodplain, Brazil - DOI: 10.4025/actascibiolsci.v27i3.1279

    Directory of Open Access Journals (Sweden)

    Maria de Los Angeles Perez Lizama

    2005-03-01

    Full Text Available Trinta e nove espécimes de Plagioscion squamosissimus Heckel, 1840 foram coletados com redes de espera de diferentes malhagens na planície de inundação do Alto rio Paraná. Foi registrada a ocorrência de Diplectanum piscinarius Kritsky e Thatcher, 1984, que apresentou abundância média igual a 31, intensidade média 31,8 e prevalência 97%. Realizou-se uma análise ecológica de alguns aspectos da relação parasita-hospedeiro entre D. piscinarius e P. squamosissimus. Não houve diferenças significativas entre prevalência e intensidade de parasitismo em machos e fêmeas. Não houve correlações entre abundância e prevalência com o comprimento padrão dos hospedeiros e entre o fator de condição relativo com a abundância. Através dos resultados, é possível supor que, provavelmente, existem poucas diferenças fisiológicas e comportamentais entre hospedeiros machos e fêmeas, não ocorrem mudanças fisiológicas durante o desenvolvimento dos hospedeiros e o parasita exibe baixa patogenicidadeThirty-nine specimens of Plagioscion squamosissimus Heckel, 1840 were collected through nets of different mesh sizes in the Upper Paraná River floodplain. The occurrence of Diplectanum piscinarius Kritsky and Thatcher, 1984 was registered and it presented mean abundance of 31, mean intensity of 31.8 and prevalence of 97%. This paper also brings an ecological analysis of some aspects of the host-parasite relationship between D. piscinarius and P. squamosissimus. There were not significant differences between the prevalence and intensity of parasitism of males and females. There were not correlations between abundance and prevalence and the standard length of the hosts; and between relative condition factor (Kn and abundance. From the results it is possible to assume that there are few physiological and behavioral differences between male and female hosts. Physiological changes probably do not occur during the development of the hosts and parasites do not seem to be very pathogenic

  12. Prácticas letradas contemporáneas: claves para su desarrollo

    OpenAIRE

    Cassany, Daniel

    2009-01-01

    Cada una de las situaciones de la vida cotidiana en las que hacemos uso de habilidades de lectura y escritura constituye una práctica letrada. Se recorren diferentes situaciones y contextos donde abundan estas prácticas, y se incide en la capacidad de lectura crítica especialmente en el àmbito escolar.

  13. Copepods link quahog growth to climate

    NARCIS (Netherlands)

    Witbaard, R.; Jansma, E.; Sass, U.G.W.

    2003-01-01

    From samples collected in 1983, 1991 and 2000, a long-term growth record for the bivalve Arctica islandica from the northern North Sea was constructed with methods derived from dendrochronology. Subsequent response-function analyses demonstrated that shell growth was mainly influenced by the abundan

  14. Unravelling the Complex Motivations behind China’s FDI

    NARCIS (Netherlands)

    Yi, Zhang

    2009-01-01

    We empirically investigate the factors that drive China's outward FDI using dynamic panel methods for 27 countries from 1995 to 2002. Based on the literature review we test three hypotheses: comparative advantages in low wage countries, vertical integration towards resource and human capital abundan

  15. DINOFLAGELLATE CYST RECORDS AND HUMAN DISTURBANCE IN TWO NEIGHBORING ESTUARIES, NEW BEDFORD HARBOR AND APPONAGANSETT BAY, MASSACHUSETTS, USA

    Science.gov (United States)

    The dinoflagellate cyst records in sediments from New Bedford Harbor and Apponagansett Bay demonstrate sensitivity to environmental change caused by human activity in the watersheds over the last 500 years. Changes in the species richness, as well as absolute and relative abundan...

  16. Cleavage patterns, cell-lineages and cell specification are clues to phyletic lineages in Spiralia.

    Science.gov (United States)

    van den Biggelaar, J A; Dictus, W J; van Loon, A E

    1997-08-01

    Embryos of molluscs, annelids, nemerteans and platyhelminthes show remarkable intra- and interphyletic resemblances and differences in mesentoblast, dorso-ventral axis and trochoblast specification. These variations have been used to investigate their evolutionary relationship. In molluscs and annelids a heterochronic shift parallels evolutionary relations based on adult characters. Nemerteans and platyhelminthes lack trochal cells and differ in the specification of the mesodermal precursor cell. Nemerteans also differ fundamentally with respect to axis specification related to the first cleavage. Therefore, close phylogenetic relations exist between molluscs and annelids, whereas nemerteans and platyhelminthes are only remotely related with each other and with molluscs and annelids. PMID:15001075

  17. A phylogenetic analysis of myosin heavy chain type II sequences corroborates that Acoela and Nemertodermatida are basal bilaterians

    OpenAIRE

    Ruiz-Trillo, I.; Paps, J.; Loukota, M.; Ribera, C; Jondelius, U.; Baguñà, J; Riutort, M

    2002-01-01

    Bilateria are currently subdivided into three superclades: Deuterostomia, Ecdysozoa, and Lophotrochozoa. Within this new taxonomic frame, acoelomate Platyhelminthes, for a long time held to be basal bilaterians, are now considered spiralian lophotrochozoans. However, recent 18S rDNA [small subunit (SSU)] analyses have shown Platyhelminthes to be polyphyletic with two of its orders, the Acoela and the Nemertodermatida, as the earliest extant bilaterians. To corroborate such position and avoid ...

  18. Occurrence and distribution of tetraether membrane lipids in soils: Implications for the use of the TEX86 proxy and the BIT index

    OpenAIRE

    Weijers, J.W.H.; Schouten, S.; Spaargaren, O.; Sinninghe Damsté, J.S.

    2006-01-01

    A diverse collection of globally distributed soil samples was analyzed for its glycerol dialkyl glycerol tetraether (GDGT) membrane lipid content. Branched GDGTs, derived from anaerobic soil bacteria, were the most dominant and were found in all soils. Isoprenoid GDGTs, membrane lipids of Archaea, were also present, although in considerably lower concentration. Crenarchaeol, a specific isoprenoid membrane lipid of the non-thermophilic Crenarchaeota, was also regularly detected and its abundan...

  19. A Re-Evaluation of the Size of the White Shark (Carcharodon carcharias) Population off California, USA

    OpenAIRE

    Burgess, George H; Barry D Bruce; Cailliet, Gregor M.; Goldman, Kenneth J.; Dean Grubbs, R.; Lowe, Christopher G.; M Aaron MacNeil; Mollet, Henry F.; Weng, Kevin C.; John B O'Sullivan

    2014-01-01

    White sharks are highly migratory and segregate by sex, age and size. Unlike marine mammals, they neither surface to breathe nor frequent haul-out sites, hindering generation of abundance data required to estimate population size. A recent tag-recapture study used photographic identifications of white sharks at two aggregation sites to estimate abundance in "central California" at 219 mature and sub-adult individuals. They concluded this represented approximately one-half of the total abundan...

  20. What planetary nebulae tell us about helium and the CNO elements in Galactic bulge stars

    OpenAIRE

    Buell, James F.

    2012-01-01

    Thermally pulsing asymptotic giant branch (TP-AGB) models of bulge stars are calculated using a synthetic model. The goal is to infer typical progenitor masses and compositions by reproducing the typical chemical composition and central star masses of planetary nebulae (PNe) in the Galactic bulge. The AGB tip luminosity and the observation that the observed lack of bright carbon stars in the bulge are matched by the models. Five sets of galactic bulge PNe were analyzed to find typical abundan...

  1. Effect of dispersal and nutrient availability on the competitive ability of toxin-producing yeast

    OpenAIRE

    Wloch-Salamon, Dominika M; Gerla, Daan; Hoekstra, Rolf F.; de Visser, J. Arjan G.M.

    2008-01-01

    The ecological role of interference competition through toxin production is not well understood. In particular, it is unclear under what conditions the benefits of toxic killing outweigh the metabolic costs involved. A killer advantage has been suggested to rely on local competitive interactions where the benefits of killing accrue to the toxin producer preferentially, but this notion has little empirical support. In addition, contrasting predictions exist about the effect of resource abundan...

  2. PEA PEEL WASTE: A LIGNOCELLULOSIC WASTE AND ITS UTILITY IN CELLULASE PRODUCTION BY Trichoderma reesei UNDER SOLID STATE CULTIVATION

    OpenAIRE

    Nitin Verma; Mukesh C. Bansal; Vivek Kumar

    2011-01-01

    A wide variety of waste bioresources are available on our planet for conversion into bioproducts. In the biological systems, microorganisms are used to utilize waste as an energy source for the synthesis of valuable products such as biomass proteins and enzymes. The large quantities of byproducts generated during the processing of plant food involve an economic and environmental problem due to their high volumes and elimination costs. After isolation of the main constituent, there are abundan...

  3. Diet rapidly and reproducibly alters the human gut microbiome

    OpenAIRE

    David, Lawrence A; Maurice, Corinne F; Carmody, Rachel N.; Gootenberg, David B.; Button, Julie E.; Wolfe, Benjamin E.; Ling, Alisha V.; Devlin, A. Sloan; Varma, Yug; Fischbach, Michael A.; Biddinger, Sudha B.; Dutton, Rachel J.; Turnbaugh, Peter J.

    2013-01-01

    Long-term diet influences the structure and activity of the trillions of microorganisms residing in the human gut 1–5 , but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here, we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundan...

  4. HARPS spectropolarimetry of three sharp-lined Herbig Ae stars: New insights

    OpenAIRE

    Järvinen, S. P.; Carroll, T. A.; Hubrig, S.; Schöller, M; Ilyin, I; Korhonen, H.; Pogodin, M.; Drake, N.A

    2015-01-01

    Several arguments have been presented that favour a scenario in which the low detection rate of magnetic fields in Herbig Ae stars can be explained by the weakness of these fields and rather large measurement uncertainties. Spectropolarimetric studies involving sharp-lined Herbig Ae stars appear to be promising for the detection of such weak magnetic fields. These studies offer a clear spectrum interpretation with respect to the effects of blending, local velocity fields, and chemical abundan...

  5. Effets des caractéristiques du champ sur l'abondance des bourdons (Bombus spp.) et sur la récolte de graines dans les champs de trèfle des prés.

    OpenAIRE

    Wermuth, Kirstain H.; Dupont, Yoko L.

    2010-01-01

    Red clover is a key floral ressource for bumblebees (Bombus spp.). We here investigate variation within and among red clover fields in species richness and abundance of Bombus spp. in addition to Apis mellifera. Bumblebee individuals were grouped into the following functional groups, based on castes and tongue length: (1) all queens, (2) all workers, (3) short-tongued workers and (4) long-tongued workers. In 14 study fields, no spatial or diurnal within-field differences were found in abundan...

  6. SCREENING, ISOLATION, IDENTIFICATION OF HOMOFERMENTATIVE BACILLI AND HOMOFERMENTATIVE COCCI FROM IDLI BATTER AND ESTIMATION OF LACTIC ACID PRODUCED BY THEM TO GET THE HIGHEST YIELD GIVING ORGANISM

    OpenAIRE

    Pathak LP*, Mali RD and PS Deshmukh

    2013-01-01

    Lactic acid is an organic acid produced by bacterial fermentation. It has several industrial applications. Lactic acid has been produced on commercial scale using various Lactic acid bacteria.   Lactobacillus leishmanii is the most commonly employed species4. Screening for high yielding Lactic acid producing bacillus or coccus from natural source will improve its commercial value. Lactic acid bacteria include some rod shaped genera and some genera with the morphology, cocci2. They are abundan...

  7. Aspectos ecológicos de Diplectanum piscinarius (Platyhelminthes, Monogenea) parasita de brânquias de Plagioscion squamosissimus (Osteichthyes, Sciaenidae) da plan. inund. Alto rio Paraná, B - DOI: 10.4025/actascibiolsci.v27i3.1279 Ecological aspects of Diplectanum piscinarius (Platyhelminthes, Monogenea) parasite of gills of Plagioscion squamosissimus (Osteichthyes, Sciaenidae) in the Upper Paraná River floodplain, Brazil - DOI: 10.4025/actascibiolsci.v27i3.1279

    OpenAIRE

    Maria de Los Angeles Perez Lizama; Gilberto Cezar Pavanelli; Gislaine Marcolino Guidelli; Ricardo Massato Takemoto; Sybelle Bellay; Fernando de Castro Tavernari

    2005-01-01

    Trinta e nove espécimes de Plagioscion squamosissimus Heckel, 1840 foram coletados com redes de espera de diferentes malhagens na planície de inundação do Alto rio Paraná. Foi registrada a ocorrência de Diplectanum piscinarius Kritsky e Thatcher, 1984, que apresentou abundância média igual a 31, intensidade média 31,8 e prevalência 97%. Realizou-se uma análise ecológica de alguns aspectos da relação parasita-hospedeiro entre D. piscinarius e P. squamosissimus. Não houve diferenças significati...

  8. A new species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on Trichodactylus fluviatilis Latreille (Crustacea, Decapoda, Trichodactylidae from southern Brazil Nova espécie de Temnocephala Blanchard ectosimbionte sobre Trichodactylus fluviatilis Latreille (Crustacea, Decapoda, Trichodactylidae da região Sul do Brasil

    Directory of Open Access Journals (Sweden)

    José F. R. Amato

    2006-09-01

    Full Text Available Temnocephala trapeziformis sp. nov., ectosymbiont on Trichodactylus fluviatilis Latreille, 1828 is described from the State of Rio Grande do Sul, southern Brazil. Sixty-eight crabs were examined, of which 61 (89.7 % were positive for this species of the genus Temnocephala Blanchard, 1849. Eggs, as well as adult and young specimens, were found on the pleural areas of the carapace, in the orbital cavities, and, usually, on the fourth pair of pereiopods. The temnocephalans were always devoid of body pigmentation, although they kept the red eye pigment, undiluted in specimens fixed by hot (90ºC phosphate buffered 10% formalin. The most distinctive characters of the new species are: 1 the shape and size of the cirrus and the characteristics of its introvert section; 2 the trapezoidal shape of the dorsolateral post-tentacular 'excretory' epidermal syncytial plates, with the nephridiopore in the lower inner corner of the plate; and 3 the number, size, and distribution of the rhabdite producing glands, as observed in very young specimens.Temnocephala trapeziformis sp. nov., ectosimbionte sobre Trichodactylus fluviatilis Latreille, 1828 é descrita para o Estado do Rio Grande do Sul, região sul do Brasil. Sessenta e oito caranguejos foram examinados, sendo que 61 (89,7 % estavam positivos para esta espécie do gênero Temnocephala Blanchard, 1849. Posturas estavam localizadas, sobre as pleuras da carapaça, nas cavidades orbitais e no quarto par de pereiópodos, locais onde também foram encontrados espécimes jovens e adultos. Os temnocefalídeos sempre se apresentaram sem pigmento corporal, embora o pigmento vermelho dos olhos tenha sido preservado nos espécimes fixados em formalina 10% fosfato tamponada (90ºC. Os caracteres mais distintos da nova espécie são: 1 a forma e o tamanho do cirro e as características do 'introvert', 2 as placas sinciciais 'excretoras' trapeziformes, com o nefridióporo sempre deslocado para o canto inferior interno de cada placa, e 3 o número, o tamanho e a distribuição das glândulas produtoras de rabdites, observadas em espécimes muito jovens.

  9. Echinococcus granulosus fatty acid binding proteins subcellular localization.

    Science.gov (United States)

    Alvite, Gabriela; Esteves, Adriana

    2016-05-01

    Two fatty acid binding proteins, EgFABP1 and EgFABP2, were isolated from the parasitic platyhelminth Echinococcus granulosus. These proteins bind fatty acids and have particular relevance in flatworms since de novo fatty acids synthesis is absent. Therefore platyhelminthes depend on the capture and intracellular distribution of host's lipids and fatty acid binding proteins could participate in lipid distribution. To elucidate EgFABP's roles, we investigated their intracellular distribution in the larval stage by a proteomic approach. Our results demonstrated the presence of EgFABP1 isoforms in cytosolic, nuclear, mitochondrial and microsomal fractions, suggesting that these molecules could be involved in several cellular processes.

  10. The evolution of the serotonergic nervous system.

    OpenAIRE

    Hay-Schmidt, A

    2000-01-01

    The pattern of development of the serotonergic nervous system is described from the larvae of ctenophores, platyhelminths, nemerteans, entoprocts, ectoprocts (bryozoans), molluscs, polychaetes, brachiopods, phoronids, echinoderms, enteropneusts and lampreys. The larval brain (apical ganglion) of spiralian protostomes (except nermerteans) generally has three serotonergic neurons and the lateral pair always innervates the ciliary band of the prototroch. In contrast, brachiopods, phoronids, echi...

  11. To be or not to be a flatworm: the acoel controversy.

    Directory of Open Access Journals (Sweden)

    Bernhard Egger

    Full Text Available Since first described, acoels were considered members of the flatworms (Platyhelminthes. However, no clear synapomorphies among the three large flatworm taxa -- the Catenulida, the Acoelomorpha and the Rhabditophora -- have been characterized to date. Molecular phylogenies, on the other hand, commonly positioned acoels separate from other flatworms. Accordingly, our own multi-locus phylogenetic analysis using 43 genes and 23 animal species places the acoel flatworm Isodiametra pulchra at the base of all Bilateria, distant from other flatworms. By contrast, novel data on the distribution and proliferation of stem cells and the specific mode of epidermal replacement constitute a strong synapomorphy for the Acoela plus the major group of flatworms, the Rhabditophora. The expression of a piwi-like gene not only in gonadal, but also in adult somatic stem cells is another unique feature among bilaterians. These two independent stem-cell-related characters put the Acoela into the Platyhelminthes-Lophotrochozoa clade and account for the most parsimonious evolutionary explanation of epidermal cell renewal in the Bilateria. Most available multigene analyses produce conflicting results regarding the position of the acoels in the tree of life. Given these phylogenomic conflicts and the contradiction of developmental and morphological data with phylogenomic results, the monophyly of the phylum Platyhelminthes and the position of the Acoela remain unresolved. By these data, both the inclusion of Acoela within Platyhelminthes, and their separation from flatworms as basal bilaterians are well-supported alternatives.

  12. Planarians sense simulated microgravity and hypergravity

    NARCIS (Netherlands)

    T. Adell; E. Sálo; J.J.W.A. van Loon; G. Auletta

    2014-01-01

    Planarians are flatworms, which belong to the phylum Platyhelminthes. They have been a classical subject of study due to their amazing regenerative ability, which relies on the existence of adult totipotent stem cells. Nowadays they are an emerging model system in the field of developmental, regener

  13. Meiofavna Strunjanskega zaliva 18 let pozneje: ponovljena raziskava:

    OpenAIRE

    Vrišer, Borut

    1999-01-01

    To establish potential long-term changes, a meiofaunal sampling along a transect of 5 ststions (1, 2.5, 5, 10, 15 m) was repeated 18 years (1979, 1997) after the first meiobenthic study in the Bay of Strunjan... Prispevek obravnava raziskavo abundančnih značilnosti meiofavne vzdolž globinskega profila 5 postaj od 1 do 15 m, ki smo jo po 18 letih (1979-1997) ponovili v Strunjanskem zalivu. Rezultati potrjujejo starejše podatke o obstoju dveh asociacij meiofavne - prva je vezana na pas morsk...

  14. INCENDIARIOS "Es preferible morir por el fuego, en combate, que morir en casa, por el hambre: Fidel Castro" Arson

    OpenAIRE

    Lisieux Elaine de BorbaTelles; Helena Dias de Castro Bins; Alcina Juliana Soares Barros; Franklin Escobar Córdoba

    2012-01-01

    Antecedentes. El concepto de fuego siempre ha atraído la atención del hombre. En la literatura abundan referencias a este término, que tanto puede representar poder y pasión como terror y destrucción. El incendio es un delito de fácil ejecución, pero de difícil investigación. La prevalencia de este delito es de 1,13%. La incidencia de este crimen está creciendo alrededor del mundo, provocando un impacto social importante por las pérdidas financieras, muertes, lesiones físicas y secuelas emoci...

  15. Es preferible morir por el fuego, en combate, que morir en casa, por el hambre: Fidel castro

    OpenAIRE

    Borba Telles, Lisieux Elaine de; Bins, Helena Dias de Castro; Barros, Alcina Juliana Soares; Escobar Córdoba, Franklin

    2012-01-01

    Antecedentes. El concepto de fuego siempre ha atraído la atención del hombre. En la literatura abundan referencias a este término, que tanto puede representar poder y pasión como terror y destrucción. El incendio es un delito de fácil ejecución, pero de difícil investigación. La prevalencia de este delito es de 1,13%. La incidencia de este crimen está creciendo alrededor del mundo, provocando un impacto social importante por las pérdidas financieras, muertes, lesiones físicas y secuelas emoci...

  16. La otra bibliografía sobre los indígenas de Chiapas

    OpenAIRE

    Viqueira, Juan Pedro

    2005-01-01

    Sobre los indígenas de Chiapas y sobre el zapatismo, se han escrito y publicado decenas y decenas de libros, casi todos ellos con propósitos propagandísticos (a favor de uno u otro bando). Estos libros ‑‑hechos apresuradamente, tras breves estancias en Chiapas y en los que abundan los lugares comunes simplistas, los estereotipos reduccionistas, los análisis políticamente correctos y los datos erróneos, falsos o de plano inventados‑‑, han tenido un éxito sorprendente y han creado una imagen de...

  17. El uso del marketing y de la comunicación corporativa en los movimientos sociales contrahegemónicos de la sociedad postindustrial

    OpenAIRE

    Gallardo Vera, Luis

    2013-01-01

    El artículo demuestra que el uso del marketing y de la comunicación corporativa es válido para obtener eficazmente los objetivos de los movimientos sociales contrahegemónicos actuales. Las investigaciones sobre el uso del marketing y de la comunicación corporativa en los movimientos sociales contrahegemónicos no abundan. En ningún caso abordan la validez del uso del marketing y de la comunicación corporativa para la consecución de los objetivos de los movimientos sociales contrahegemónico...

  18. La aplicación de la segmentación al Movimiento 15-M

    OpenAIRE

    Gallardo Vera, Luis

    2012-01-01

    El artículo demuestra que la operación de la segmentación (técnica de marketing y de comunicación corporativa ideada para conseguir eficazmente los objetivos de las organizaciones) es válida para obtener eficazmente los objetivos del Movimiento 15-M. Las investigaciones sobre el uso del marketing y de la comunicación corporativa en el Movimiento 15-M no abundan. Las investigaciones efectuadas abordan sucintamente cuestiones de estrategia y de comunicación corporativas. En ningún caso abor...

  19. La Policía Local como Policía Integral Básica en el modelo policial español

    OpenAIRE

    Campos Doménech, Alejandro

    2015-01-01

    La Policía Local es una de las instituciones públicas menos investigadas. Esta ausencia de estudios contrasta con su importancia y con la evolución sufrida en los últimos tiempos, a lo que se añade que cuando existen publicaciones sobre la misma, estas se centran en aspectos políticos o jurídicos pero no abundan en el funcionamiento organizativo, las tareas o las relaciones con la población, es decir, se discute el modelo en sus aspectos normativos y/o políticos pero no la realidad. Por añadi...

  20. Efectos inmunológicos del tratamiento psicológico a enfermos de cáncer: ¿qué sabemos?

    OpenAIRE

    Fusté Escolano, Adela; Ruiz Rodríguez, José

    2008-01-01

    El diagnóstico y tratamiento del cáncer está asociado a manifestaciones psicológicas negativas tales como estrés, ansiedad, depresión, etc (Carver, Pozo, Harris et al. 1993). En el ámbito de la psiconeuroinmunología, abundan las investigaciones que sugieren un efecto depresor de tales manifestaciones (Cohen y Williamson, 1991) sobre el sistema inmune, o, en cualquier caso, del efecto modulador del estrés sobre la respuesta inmunológica del individuo (Contrada et al. 1990). Diversos modelos ps...

  1. 7. Cordeles y libros de ayllu

    OpenAIRE

    Salomon, Frank

    2015-01-01

    En Tupicocha abundan los archivos escritos. No sólo existe el archivo comunitario, que conserva los títulos coloniales y la administración moderna de la comunidad campesina, sino también archivos escritos espontáneamente porcada parcialidad o ayllu individual, independientemente de la supervisión del Estado. Los libros del ayllu aluden a los quipocamayos sin explicar qué información guardaban estos cordeles. Sin embargo, los libros y los cordeles pertenecen a períodos traslapados. Ambos regis...

  2. El Esoterismo y la adivinación como fenómeno comunicativo en la televisión española

    OpenAIRE

    Cid-Leal, Pilar; Recoder, Maria Josep; Cruz Palacios, Emilio

    2015-01-01

    En las parrillas nocturnas de los canales de Televisión Digital Terrestre (TDT) españoles abundan los programas de adivinación con consultas telefónicas. Pese a las transformaciones que ha experimentado el medio televisivo en los últimos años, estos programas, difícilmente clasificables dentro de los géneros televisivos clásicos, se mantienen. Porque son tanto un fenómeno comunicativo como un negocio para las televisiones, los consultorios privados de los vident...

  3. El clientelismo en México: los usos políticos de la pobreza

    OpenAIRE

    Edgar Hernández Muñoz

    2006-01-01

    No abundan los estudios sobre clientelismo político en México. A diferencia de otros países, aquí la mayoría de las alusiones al tema se han circunscrito, si no supeditado o subsumido, a los abordajes genéricos referentes al fenómeno de la dominación política. Sin embargo, esta práctica fue consustancial al sistema corporativo en donde se practicó el monopolio del poder y, ligado a éste, el uso patrimonial de los recursos públicos.

  4. La necesidad de los Proyectos de Habilidades Socioemocionales en la Educación Secundaria Obligatoria. Estudio de un caso

    OpenAIRE

    Valcárcel Couceiro, Andrea

    2016-01-01

    Esta investigación defiende la necesidad de trabajar la dimensión socioemocional con el alumnado de educación secundaria, especialmente con aquellos que presenten problemas de conducta o estén involucrados en situaciones de acoso escolar, dando prioridad a las víctimas. Siendo conscientes de que, por una parte, en la actualidad abundan dichos perfiles trastocando el óptimo desarrollo del sujeto así como el clima del centro educativo, y por otra, que la educación no debe separar la dimensió...

  5. Pervivencia y ruptura en la legislación penal de las Cortes valencianas de Martín I (1401-1407)

    OpenAIRE

    Iñesta Pastor, Emilia

    2013-01-01

    Martín I, en las Cortes celebradas en Valencia (1401-1407) completará y modificará la legislación penal anterior en consonancia con las necesidades político-sociales del momento poniendo en evidencia los avances y pervivencias en materia penal. Es manifiesta la preocupación valenciana, común a todos los territorios de la Corona de Aragón, por el mantenimiento del orden público. Abundan las medidas adoptadas para reprimir el bandolerismo, y por su estrecha relación con la violencia la persecuc...

  6. Contribución de las entidades de economía social a la gestión eficiente del agua para uso agrícola: situación en la Región de Murcia

    OpenAIRE

    Alcón Provencio, Francisco José; Narciso ARCAS LARIO

    2007-01-01

    Esp: En la literatura abundan los trabajos dirigidos a caracterizar las entidades que integran la “Economía Social” en España y a cuantificar su contribución a los diferentes sectores económicos y, en especial, al sector agroalimentario. Sin embargo, estos trabajos no se han hecho eco de la importancia de estas organizaciones para la gestión de un recurso tan fundamental para el sector agrario como el agua, y del papel que en ella juegan las Comunidades de Regantes (CCRR), sobre todo, junto a...

  7. CONTRIBUCIÓN DE LAS ENTIDADES DE “ECONOMÍA SOCIAL” A LA GESTIÓN EFICIENTE DEL AGUA PARA USO AGRÍCOLA: SITUACIÓN EN LA REGIÓN DE MURCIA/CONTRIBUTION OF THE ENTITIES OF “SOCIAL ECONOMY” TO THE EFFICIENT MANAGEMENT OF WATER FOR AGRICULTURAL USE: SITUATION IN THE REGION OF MURCIA

    OpenAIRE

    Narciso ARCAS LARIO; Francisco ALCON PROVENCIO

    2007-01-01

    AbstractEn la literatura abundan los trabajos dirigidos a caracterizar las entidades que integran la “Economía Social” en España y a cuantificar su contribución a los diferentes sectores económicos y, en especial, al sector agroalimentario. Sin embargo, estos trabajos no se han hecho eco de la importancia de estas organizaciones para la gestión de un recurso tan fundamental para el sector agrario como el agua, y del papel que en ella juegan las Comunidades de Regantes (CCRR), sobre todo, junt...

  8. El clientelismo en México: los usos políticos de la pobreza

    Directory of Open Access Journals (Sweden)

    Edgar Hernández Muñoz

    2006-01-01

    Full Text Available No abundan los estudios sobre clientelismo político en México. A diferencia de otros países, aquí la mayoría de las alusiones al tema se han circunscrito, si no supeditado o subsumido, a los abordajes genéricos referentes al fenómeno de la dominación política. Sin embargo, esta práctica fue consustancial al sistema corporativo en donde se practicó el monopolio del poder y, ligado a éste, el uso patrimonial de los recursos públicos.

  9. Ciudades de los Andes: Homogeneización y diversidad

    OpenAIRE

    Garcés, Eduardo Kingman

    2014-01-01

    Otras gentes, otras ciudades Si algún texto dentro del marxismo clásico puede ser calificado como de corte antropológico, este es el que sobre la situación de la clase obrera en Inglaterra escribiera Federico Engels. Se trata de un estudio de juventud en el que abundan las descripciones y los datos empíricos interpretados a la luz de un balbuceante materialismo histórico. Lo interesante desde nuestra perspectiva es su visión de Londres y de la forma como la ciudad va alterando las condiciones...

  10. The urbilaterian brain revisited: novel insights into old questions from new flatworm clades.

    Science.gov (United States)

    Bailly, Xavier; Reichert, Heinrich; Hartenstein, Volker

    2013-05-01

    Flatworms are classically considered to represent the simplest organizational form of all living bilaterians with a true central nervous system. Based on their simple body plans, all flatworms have been traditionally grouped together in a single phylum at the base of the bilaterians. Current molecular phylogenomic studies now split the flatworms into two widely separated clades, the acoelomorph flatworms and the platyhelminth flatworms, such that the last common ancestor of both clades corresponds to the urbilaterian ancestor of all bilaterian animals. Remarkably, recent comparative neuroanatomical analyses of acoelomorphs and platyhelminths show that both of these flatworm groups have complex anterior brains with surprisingly similar basic neuroarchitectures. Taken together, these findings imply that fundamental neuroanatomical features of the brain in the two separate flatworm groups are likely to be primitive and derived from the urbilaterian brain. PMID:23143292

  11. THE URBILATERIAN BRAIN REVISITED: NOVEL INSIGHTS INTO OLD QUESTIONS FROM NEW FLATWORM CLADES

    OpenAIRE

    Bailly, Xavier; Reichert, Heinrich; Hartenstein, Volker

    2012-01-01

    Flatworms are classically considered to represent the simplest organizational form of all living bilaterians with a true central nervous system. Based on their simple body plans, all flatworms have been traditionally grouped together in a single phylum at the base of the bilaterians. Current molecular phylogenomic studies now split the flatworms into two widely separated clades, the acoelomorph flatworms and the platyhelminth flatworms, such that the last common ancestor of both clades corres...

  12. DNA primers for amplification of mitochondrial cytochrome c oxidase subunit I from diverse metazoan invertebrates.

    Science.gov (United States)

    Folmer, O; Black, M; Hoeh, W; Lutz, R; Vrijenhoek, R

    1994-10-01

    We describe "universal" DNA primers for polymerase chain reaction (PCR) amplification of a 710-bp fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) from 11 invertebrate phyla: Echinodermata, Mollusca, Annelida, Pogonophora, Arthropoda, Nemertinea, Echiura, Sipuncula, Platyhelminthes, Tardigrada, and Coelenterata, as well as the putative phylum Vestimentifera. Preliminary comparisons revealed that these COI primers generate informative sequences for phylogenetic analyses at the species and higher taxonomic levels.

  13. Posterior regeneration in Isodiametra pulchra (Acoela, Acoelomorpha)

    OpenAIRE

    Perea-Atienza, Elena; Botta, Maria; Salvenmoser, Willi; Gschwentner, Robert; Egger, Bernhard; Kristof, Alen; Martinez, Pedro; Achatz, Johannes Georg

    2013-01-01

    Introduction Regeneration is a widespread phenomenon in the animal kingdom, but the capacity to restore damaged or missing tissue varies greatly between different phyla and even within the same phylum. However, the distantly related Acoelomorpha and Platyhelminthes share a strikingly similar stem-cell system and regenerative capacity. Therefore, comparing the underlying mechanisms in these two phyla paves the way for an increased understanding of the evolution of this developmental process. T...

  14. Why the radiation-attenuated cercarial immunization studies failed to guide the road for an effective schistosomiasis vaccine: A review

    OpenAIRE

    Rashika El Ridi; Hatem Tallima

    2014-01-01

    Schistosomiasis is a debilitating parasitic disease caused by platyhelminthes of the genus Schistosoma, notably Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum. Pioneer researchers used radiation-attenuated (RA) schistosome larvae to immunize laboratory rodent and non-human primate hosts. Significant and reproducible reduction in challenge worm burden varying from 30% to 90% was achieved, providing a sound proof that vaccination against this infection is feasible. Exte...

  15. Global Expression Analysis Revealed Novel Gender-Specific Gene Expression Features in the Blood Fluke Parasite Schistosoma japonicum

    OpenAIRE

    Xianyu Piao; Pengfei Cai; Shuai Liu; Nan Hou; Lili Hao; Fan Yang; Heng Wang; Jianwei Wang; Qi Jin; Qijun Chen

    2011-01-01

    BACKGROUND: Schistosoma japonicum is one of the remarkable Platyhelminths that are endemic in China and Southeast Asian countries. The parasite is dioecious and can reside inside the host for many years. Rapid reproduction by producing large number of eggs and count-react host anti-parasite responses are the strategies that benefit long term survival of the parasite. Praziquantel is currently the only drug that is effective against the worms. Development of novel antiparasite reagents and imm...

  16. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites

    OpenAIRE

    Biswal, Devendra Kumar; Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providin...

  17. Aquaculture et ichtyoparasitologie: action in vitro du Nitroxinil© (Antihelminthique) sur Diplectanum aequans , ectoparasite branchial du bar Dicentrarchus labrax

    OpenAIRE

    Silan, Patrick; Birgi, Emile; Louis, Christophe; Clota,, Frédéric; Mathieu, André; Giral, Louis

    1996-01-01

    International audience The sea bass Dicentrarchus labrax is subject to intensive rearing. Several monogeneans, gill ectoparasites with a direct biological cycle, parasitized this Teleostei. Under certain conditions of host density, populations of these platyhelminths can increase and consequently induce important mortality. It's especially the case of Diplectanum aequans, a monopisthocotylea against which no treatment is known. In vitro effects of nitroxinil© (or nitroxynil©), an anthelmin...

  18. Macrobenthic fauna community in the Middle Songkhla Lake, Southern Thailand

    OpenAIRE

    Angsupanich, S.; Charoenpornthip, M.; Siripech, A.

    2005-01-01

    A bimonthly investigation of macrobenthic fauna at the area from Ban Pak Khat to Ban Leam Chong Thanon in the Inner Songkhla Lake from February 1998 to February 1999 was undertaken to determine the species richness and abundance. A total of 7 phyla and 161 species were identified. Annelida (58 species), Arthropoda (64 species) and Mollusca (23 species) were the major phyla while Nemertea (1 species), Platyhelminthes (1 species), Cnidaria (4 species) and Chordata (10 species) were the minor. F...

  19. Lipid Binding Proteins from Parasitic Platyhelmithes

    Directory of Open Access Journals (Sweden)

    Gabriela eAlvite

    2012-09-01

    Full Text Available Two main families of lipid binding proteins have been identified in parasitic Platyhelminthes: hydrophobic ligand binding proteins (HLBPs and fatty acid binding proteins (FABPs. Members of the former family of proteins are specific to the Cestoda class, while FABPs are conserved across a wide range of animal species. Because Platyhelminthes are unable to synthesise their own lipids, these lipid-binding proteins are important molecules in these organisms.HLBPs are a high molecular mass complex of proteins and lipids. They are composed of subunits of low molecular mass proteins and a wide array of lipid molecules ranging from CoA esters to cholesterol. These proteins are excretory-secretory molecules and are key serological tools for diagnosis of diseases caused by cestodes. FABPs are mainly intracellular proteins of low molecular weight. They are also vaccine candidates.Despite that the knowledge of their function is scarce, the differences in their molecular organisation, ligand preferences, intra/extracellular localisation, evolution, and phylogenetic distribution, suggest that platyhelminths HLBPs and FABPs should play different functions. FABPs might be involved in the removal of fatty acids from the inner surface of the cell membrane and in their subsequent targeting to specific cellular destinations. In contrast, HLBPs might be involved in fatty acid uptake from the host environment.

  20. “Swedish Freemasonry in the Caribbean: How St. Barthélemy turned into an Island of the IXth Province”

    Directory of Open Access Journals (Sweden)

    Andreas Önnerfors

    2009-01-01

    Full Text Available Este artículo examina la organización de la masonería en San Bartolomé, sus relacion es con la Gran Logia de Suecia, su estructura y actividades. Relaciones que hast a ahora nunca han sido analizadas. El estudio se centra principalmente entre los años 1797-1807, periodo en donde abundan documentos acerca de los rituales de trabajo, la organización y las ideologías de las logias. Por último, un aporte fundame ntal de esta investigación está en que por primera son utilizadas fuentes acerca de la orden masónica sueca presentes en los archivos de la logia La Sudermanie de la capital de San Bartolomé, Gustavia.

  1. Conceptos fundamentales sobre el mantenimiento de edificios

    Directory of Open Access Journals (Sweden)

    Juan Miguel Arencibia Fernández

    2007-01-01

    Full Text Available En esta investigación se realiza una profunda búsqueda sobre el tema del Mantenimiento de Edificios donde se abundan diferentes conceptos y criterios de la misma, encontrándose de esta forma los más utilizados métodos a emplear. Luego teniendo en cuenta las clasificación del Mantenimiento de Edificio según los tipos de obras, propietarios del inmueble y el momento que éste se realiza, como los costos de una edificación y su equipamiento a utilizar. Otros de los aspectos a tener en cuenta es la organización del Mantenimiento su planificación y responsabilidad, las ventajas que puede traer tanto para la economía y para el mismo usuario, como su vida útil, para el cual fueron ejecutadas las edificaciones.

  2. Palabras y actitudes de mujeres de la Cataluña bajomedieval ante las violencias e injusticias

    Directory of Open Access Journals (Sweden)

    Mireia Comas Via

    2013-12-01

    Full Text Available En la documentación catalana bajo-medieval abundan los testimonios de mujeres maltratadas, mujeres de todas las edades que sufrían vejaciones y palizas de los hombres que tenían a su alrededor: padres, abuelos, maridos, etc. En este artículo, nos hemos fijado, sobre todo en la documentación judicial y los reque-rimientos notariales, para seguir la pista, no solo a los malos tratos que padecieron algunas muje-res, sino también a las actitudes que adoptaron ante tales agresiones. A través de las diferentes etapas de la vida de las mujeres, se analizan las circunstancias de los malos tratos que sufrían: desde los esponsales de matrimonios forzosos hasta la viudedad y las segundas nupcias.

  3. El vulcanismo en el Sistema Solar

    OpenAIRE

    Anguita, Francisco

    1999-01-01

    El vulcanismo es el proceso geológico más común en el Sistema Solar. En la Tierra y en Marte, los magmas más frecuentes son el basáltico y el andesítico; en general, los basaltos parecen ser la roca volcánica predominante en todo el interior del Sistema Solar, mientras que en el exterior abundan los magmas de volátiles, sobre todo agua. Tras una rápida revisión del vulcanismo en los principales cuerpos planetarios, se analiza su marco dinámico: mientras que en la Tierra hay magmas en borde...

  4. Radiative transfer in cylindrical threads with incident radiation VI. A hydrogen plus helium system

    CERN Document Server

    Gouttebroze, Pierre

    2009-01-01

    Spectral lines of helium are commonly observed on the Sun. These observations contain important informations about physical conditions and He/H abundance variations within solar outer structures. The modeling of chromospheric and coronal loop-like structures visible in hydrogen and helium lines requires the use of appropriate diagnostic tools based on NLTE radiative tranfer in cylindrical geometry. We use iterative numerical methods to solve the equations of NLTE radiative transfer and statistical equilibrium of atomic level populations. These equations are solved alternatively for the hydrogen and helium atoms, using cylindrical coordinates and prescribed solar incident radiation. Electron density is determined by the ionization equilibria of both atoms. Two-dimension effects are included. The mechanisms of formation of the principal helium lines are analyzed and the sources of emission inside the cylinder are located. The variations of spectral line intensities with temperature, pressure, and helium abundan...

  5. La creatividad en el modelo instructivo de los textos escolares

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    Manuel LORENZO DELGADO

    2009-11-01

    Full Text Available Ciertamente el tema de la creatividad constituye hoy uno de los núcleos favoritos de las ciencias pedagógicas. No es extraño, por ello, que se haya abordado desde las más variadas perspectivas y enfoques. El «Simposium Nacional sobre Creatividad», celebrado en Valencia en 1982, por ejemplo, recoge análisis que van desde la perspectiva histórica hasta la filosófica, psicológica o las aplicadas al arte, lenguaje y juego. Sin embargo, no abundan los acercamientos descriptivos y empíricos a partir de la Didáctica, aunque sí exista un amplio abanico de aplicaciones normativas —técnicas—, que estimulan la creatividad en el aula.

  6. The repertoire of G protein-coupled receptors in the human parasite Schistosoma mansoni and the model organism Schmidtea mediterranea

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    Zamanian Mostafa

    2011-12-01

    Full Text Available Abstract Background G protein-coupled receptors (GPCRs constitute one of the largest groupings of eukaryotic proteins, and represent a particularly lucrative set of pharmaceutical targets. They play an important role in eukaryotic signal transduction and physiology, mediating cellular responses to a diverse range of extracellular stimuli. The phylum Platyhelminthes is of considerable medical and biological importance, housing major pathogens as well as established model organisms. The recent availability of genomic data for the human blood fluke Schistosoma mansoni and the model planarian Schmidtea mediterranea paves the way for the first comprehensive effort to identify and analyze GPCRs in this important phylum. Results Application of a novel transmembrane-oriented approach to receptor mining led to the discovery of 117 S. mansoni GPCRs, representing all of the major families; 105 Rhodopsin, 2 Glutamate, 3 Adhesion, 2 Secretin and 5 Frizzled. Similarly, 418 Rhodopsin, 9 Glutamate, 21 Adhesion, 1 Secretin and 11 Frizzled S. mediterranea receptors were identified. Among these, we report the identification of novel receptor groupings, including a large and highly-diverged Platyhelminth-specific Rhodopsin subfamily, a planarian-specific Adhesion-like family, and atypical Glutamate-like receptors. Phylogenetic analysis was carried out following extensive gene curation. Support vector machines (SVMs were trained and used for ligand-based classification of full-length Rhodopsin GPCRs, complementing phylogenetic and homology-based classification. Conclusions Genome-wide investigation of GPCRs in two platyhelminth genomes reveals an extensive and complex receptor signaling repertoire with many unique features. This work provides important sequence and functional leads for understanding basic flatworm receptor biology, and sheds light on a lucrative set of anthelmintic drug targets.

  7. Thyroid hormone receptor orthologues from invertebrate species with emphasis on Schistosoma mansoni

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    Niles Edward G

    2007-08-01

    Full Text Available Abstract Background: Thyroid hormone receptors (TRs function as molecular switches in response to thyroid hormone to regulate gene transcription. TRs were previously believed to be present only in chordates. Results: We isolated two TR genes from the Schistosoma mansoni and identified TR orthologues from other invertebrates: the platyhelminths, S. japonium and Schmidtea mediterranea, the mollusc, Lottia gigantean and the arthropod Daphnia pulex. Phylogenetic analysis of the DNA binding domain and/or ligand binding domain shows that invertebrate and vertebrate TRs cluster together, TRs from the vertebrates and from the jawless vertebrate (lamprey clustered within separate subgroups, Platyhelminth TRs cluster outside of the vertebrate TR subgroups and that the schistosome TRs and S. mediterranea TRs clustered within separate subgroups. Alignment of the C-terminus of the A/B domain revealed a conserved TR-specific motif, termed TR 'N-terminus signature sequence', with a consensus sequence of (G/PYIPSY(M/LXXXGPE(D/EX. Heterodimer formation between S. mansoni TRs and SmRXR1 suggests that the invertebrate TR protein gained the ability to form a heterodimer with RXR. ESMA analysis showed that SmTRα could bind to a conserved DNA core motif as a monomer or homodimer. Conclusion: Vertebrate TR genes originated from a common ancestor of the Bilateria. TR genes underwent duplication independently in the Protostomia and Deuterostomia. The duplication of TRs in deuterostomes occurred after the split of jawless and jawed vertebrates. In protostomes, TR genes underwent duplication in Platyhelminths, occurring independently in trematode and turbellarian lineages. Using S. mansoni TRs as an example, invertebrate TRs exhibited the ability to form a dimer with RXR prior to the emergence of the vertebrate TRs and were able to bind to vertebrate TR core DNA elements as a monomer or homodimer.

  8. Endoparasites of some economically important food fishes of River Jhelum, Kashmir (India).

    Science.gov (United States)

    Farooq, Taqdees; Khan, Imran; Tak, Irfan-Ur-Rauf; Dar, Shoaib Ali; Yousuf, A R

    2016-09-01

    During the present study endo-parasitic fauna of fish at different sites of River Jhelum were analysed. Four different species of endoparasites were recovered from Schizothorax species which include Adenoscolex kashmirensis Mehra, 1930, Bothriocephalus acheilognathi Yamaguti, 1934, Echinorhynchus sp., Pomphorhynchus kashmirensis Kaw, 1941, belong to Phylum Platyhelminths and Phylum Acanthocephala. Prevalence and generation time were inversely proportional to each other. Prevalence and mean abundance were highest at Qamarwari. Diversity was more at Tengpora. Cestodes including Adenoscolex kashmirensis and Bothriocephalus acheilognathi were more dominant than Pomphorhynchus kashmirensis and Echinorhynchus sp.

  9. Spermatogenesis and spermiogenesis in Didymocystis wedli Ariola, 1902 (Didymozoidae, Digenea

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    MC Pamplona-Basilio

    2001-11-01

    Full Text Available The ultrastructure of the male reproductive system of Didymocystis wedli was studied for the first time, demonstrating spermiogenesis and spermatogenesis at different cell stages. The spermatozoa morphology was compared with that of other Digenea species. It was observed that the different cells of the spermatogenesis process follow the classic pattern reported for the majority of the parasitic platyhelminthes. During spermiogenesis, rootlet fibers, electrondense bodies and median cytoplasmic process were not observed. The mature spermatozoa of D. wedli were filiform, presenting nucleus, mitochondrion and two 9+1 axonemes, with a biflagellate distal extremity.

  10. Trematodes in Mediterranean coastal habitats: Transmission, life cycles and detection Methods

    OpenAIRE

    Born Torrijos, Ana Isabel

    2015-01-01

    1. Introducción general Los metazoos trematodos (Platyhelminthes) son componentes ubicuos de los ecosistemas naturales entando temporal o permanentemente presentes en más de la mitad de las especies animales (Bush y col. 2001, Prietrock & Marcogliese 2003). Los parásitos trematodos pueden encontrarse en un amplio rango de condiciones y hábitats, teniendo un gran impacto en los procesos ecológicos: mediante la regulación de las poblaciones de hospedadores (Hudson y col. 2006) y afectando a ...

  11. Taxonomy Icon Data: Schistosoma japonicum [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Schistosoma japonicum Schistosoma japonicum Platyhelminthes Schistosoma_japonicum_L.png Schistosoma_japonic...um_NL.png Schistosoma_japonicum_S.png Schistosoma_japonicum_NS.png http://bioscience...dbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonicum&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonic...um&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonic...um&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonicum&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=132 ...

  12. Lista dos Anelídeos (Annelida)

    OpenAIRE

    Paulo A V Borges

    2010-01-01

    A diversidade das minhocas (Annelida) é aqui compilada, em adição aos grupos de animais terrestres listados em detalhe noutros capítulos deste livro (Platyhelminthes, Nematoda, Mollusca, Arthropoda, Chordata). Com base na recente lista de espécies animais terrestres da Europa, projecto “Fauna Europaea” (http:// www.faunaeur.org), listam-se 21 espécies de anelí deos terrestres. É apresentada a distribuição das espécies ou subespécies nas nove ilhas dos Açores, usando-se a seguinte simbologia: ...

  13. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay.

    Science.gov (United States)

    Lu, Zhigang; Sessler, Florian; Holroyd, Nancy; Hahnel, Steffen; Quack, Thomas; Berriman, Matthew; Grevelding, Christoph G

    2016-01-01

    As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects.

  14. Schistosome sex matters: a deep view into gonad-specific and pairing-dependent transcriptomes reveals a complex gender interplay.

    Science.gov (United States)

    Lu, Zhigang; Sessler, Florian; Holroyd, Nancy; Hahnel, Steffen; Quack, Thomas; Berriman, Matthew; Grevelding, Christoph G

    2016-01-01

    As a key event for maintaining life cycles, reproduction is a central part of platyhelminth biology. In case of parasitic platyhelminths, reproductive processes can also contribute to pathology. One representative example is the trematode Schistosoma, which causes schistosomiasis, an infectious disease, whose pathology is associated with egg production. Among the outstanding features of schistosomes is their dioecious lifestyle and the pairing-dependent differentiation of the female gonads which finally leads to egg synthesis. To analyze the reproductive biology of Schistosoma mansoni in-depth we isolated complete ovaries and testes from paired and unpaired schistosomes for comparative RNA-seq analyses. Of >7,000 transcripts found in the gonads, 243 (testes) and 3,600 (ovaries) occurred pairing-dependently. Besides the detection of genes transcribed preferentially or specifically in the gonads of both genders, we uncovered pairing-induced processes within the gonads including stem cell-associated and neural functions. Comparisons to work on neuropeptidergic signaling in planarian showed interesting parallels but also remarkable differences and highlights the importance of the nervous system for flatworm gonad differentiation. Finally, we postulated first functional hints for 235 hypothetical genes. Together, these results elucidate key aspects of flatworm reproductive biology and will be relevant for basic as well as applied, exploitable research aspects. PMID:27499125

  15. Molecular phylogeny of metazoan intermediate filament proteins.

    Science.gov (United States)

    Erber, A; Riemer, D; Bovenschulte, M; Weber, K

    1998-12-01

    We have cloned cytoplasmic intermediate filament (IF) proteins from a large number of invertebrate phyla using cDNA probes, the monoclonal antibody IFA, peptide sequence information, and various RT-PCR procedures. Novel IF protein sequences reported here include the urochordata and nine protostomic phyla, i.e., Annelida, Brachiopoda, Chaetognatha, Echiura, Nematomorpha, Nemertea, Platyhelminthes, Phoronida, and Sipuncula. Taken together with the wealth of data on IF proteins of vertebrates and the results on IF proteins of Cephalochordata, Mollusca, Annelida, and Nematoda, two IF prototypes emerge. The L-type, which includes 35 sequences from 11 protostomic phyla, shares with the nuclear lamins the long version of the coil 1b subdomain and, in most cases, a homology segment of some 120 residues in the carboxyterminal tail domain. The S-type, which includes all four subfamilies (types I to IV) of vertebrate IF proteins, lacks 42 residues in the coil 1b subdomain and the carboxyterminal lamin homology segment. Since IF proteins from all three phyla of the chordates have the 42-residue deletion, this deletion arose in a progenitor prior to the divergence of the chordates into the urochordate, cephalochordate, and vertebrate lineages, possibly already at the origin of the deuterostomic branch. Four phyla recently placed into the protostomia on grounds of their 18S rDNA sequences (Brachiopoda, Nemertea, Phoronida, and Platyhelminthes) show IF proteins of the L-type and fit by sequence identity criteria into the lophotrochozoic branch of the protostomia. PMID:9847417

  16. Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.

    Science.gov (United States)

    Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent

    2016-01-01

    The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. PMID:26812300

  17. Biosorptive uptake of ibuprofen by steam activated biochar derived from mung bean husk: Equilibrium, kinetics, thermodynamics, modeling and eco-toxicological studies.

    Science.gov (United States)

    Mondal, Sandip; Bobde, Kiran; Aikat, Kaustav; Halder, Gopinath

    2016-11-01

    The present study explores the use of steam activated mung bean husk biochar (SA-MBHB) as a potential sorbent for the removal of non-steroidal and anti-inflammatory drug ibuprofen from aqueous solution. SA-MBHB was characterized by SEM, FTIR, BET, TGA, point of zero charge (pHPZC) and UV-Vis spectrophotometer. The relation between removal percentages of ibuprofen and parameters such as adsorbent dose (0.05 g-250 g), contact time (5 min-210 min), pH (2-10), speed of agitation (40-280 rpm), temperature (293-308 K) and initial ibuprofen concentration (5-100 ppm) was investigated and optimized by a series of batch sorption experiments. The optimized conditions achieved were: adsorbent dose 0.1 g/L, agitation speed 200 rpm, pH 2, initial ibuprofen concentration 20 mg L(-1), equilibrium time 120 min and temperature 20 °C for more than 99% adsorptive removal of ibuprofen. The equilibrium adsorption data were well fitted into the Langmuir isotherm model while kinetic data suggested the removal process to follow pseudo second order reaction. The adsorption phenomena were optimized and simulated by using response surface methodology (RSM) and artificial neural network (ANN). Effect of process variables viz. dose, agitation speed and pH on the sorbed amount of IBP was studied through a 2(3) full factorial central composite design (CCD). The comparative analysis was done for ibuprofen removal by constructing ANN model training using same experimental matrix of CCD. The growth of Scenedesmus abundans was also observed to be affected by the IBP solution whereas the biochar treated with IBP solution did not significantly affect the growth of the Scenedesmus abundans. The results revealed that SA-MBHB could be a cost-effective, efficient and non-hazardous adsorbent for the removal of ibuprofen from aqueous solution. PMID:27544645

  18. El recurso auto-epistolar como terapia: Motivos temáticos recurrentes y greguerías en Cartas a mí mismo [1956] de Ramón Gómez de la Serna

    Directory of Open Access Journals (Sweden)

    Rafael Cabañas Alamán

    2011-12-01

    Full Text Available Ramón Gómez de la Serna wrote Letters to Myself, published as a collection in 1956, and written at the end of the 40s and early 50s. Writing these letters helped the author benefit from narrative therapy. I will analyze how they show his obsessión with death, contradictory reports about his loneliness in America and the different allusions showing happiness and unhappiness in a type of literature writing that goes from sadness to humor, in which we find many gregueríasRamón Gómez de la Serna escribió a finales de los años 40 y principios de los 50 las Cartas a mí mismo, publicadas en conjunto en 1956. La escritura de dichas cartas le sirve al autor de terapia narrativa. Analizaré cómo se muestra su obsesión por la muerte, los testimonios contradictorios de la soledad experimentada en América y diversas alusiones que reflejan felicidad e infelicidad en una escritura literaria que oscila entre la tristeza y lo lúdico, en la cual abundan las greguerías

  19. Equipo Portátil para Análisis Químicos del Suelo

    Directory of Open Access Journals (Sweden)

    Jaramillo Madarriaga G.

    1939-12-01

    Full Text Available En estos últimos años, principalmente en los Estados Unidos, ha surgido una gran variedad de equipos portátiles para el examen rápido de suelos, basados la mayor parte en reacciones calorimétricas para fósforo, potasio, nitratos y algunos otros elementos considerados de importancia para la vida de la planta. El factor que determina la gran variedad de resultados obtenidos con tales equipos es la naturaleza del disolvente empleado para extraer los elementos de la muestra de suelo, disolvente que consiste, por lo general en soluciones de distinta concentración de ácido clorhídrico, sulfúrico, acético. etc. Si se admite que estos exámenes rápidos en el campo pueden ser útiles en países donde los agricultores cuentan con grandes facilidades para hacer verificar análisis completes de sus tierras, con mayor razón debemos admitir que en nuestro país, donde no abundan los laboratorios especializados, los equipos portátiles son casi una necesidad para la orientación de los agrónomos oficiales que operan en regiones apartadas. Debido a esto, la Facultad Nacional de Agronomía se ha interesado en el desarrollo de un equipo portátil lo más compacto posible para el uso de los agrónomos.

  20. Fauna fitotelmata en las bromelias Aechmea fendleri André y Aechmea fendleri y Aechmea fendler del Parque Nacional San Esteban, Venezuela stellata S c h u l t d e l P a r q u e N a c i o n a l S a n E s t e b a n , V

    Directory of Open Access Journals (Sweden)

    Jonathan Liria

    2013-04-01

    Full Text Available El presente trabajo caracteriza la asociación de mosquitos y otros invertebrados sobre bromelias del Parque Nacional San Esteban del Estado Carabobo, Venezuela. Se estudiaron 18 plantas de Aechmea fendleri (11 Aechmea fendleri (1 1 Aechmea fendleri y Hohenbergia stellata (7 durante las épocas lluvia (Septiembre 2004 y sequía (Marzo 2005. Fueron colectados un total de 2020 macroinvertebrados. Los taxa más importantes fueron las Familias Chironomidae (43%, Culicidae (25% y Chaoboridae (6% del Orden Diptera, y Scyrtidae (5% del Orden Coleoptera. En Culicidae las especies más abundan- tes fueron: Culex consolador (31%, Cx. neglectus (27% y Wyeomyia celaenocephala (17%. La mayor abundancia y riqueza se encontró en la época de sequía, con el aumento de diversidad en Culicidae. La diversidad y equitabilidad de macroinvertebrados fue mayor H. stellata , pero similares entre estaciones para las comunidades de A. fendleri y A. fendleri y A. fendleri H. stellata .

  1. Spitzer reveals what's behind Orion's Bar

    CERN Document Server

    Rubin, Robert H; O'Dell, C R; McNabb, Ian A; Colgan, Sean W J; Zhuge, Scott Y; Ferland, Gary J; Hidalgo, Sergio A

    2010-01-01

    We present Spitzer Space Telescope observations of 11 regions SE of the Bright Bar in the Orion Nebula, along a radial from the exciting star theta1OriC, extending from 2.6 to 12.1'. Our Cycle 5 programme obtained deep spectra with matching IRS short-high (SH) and long-high (LH) aperture grid patterns. Most previous IR missions observed only the inner few arcmin. Orion is the benchmark for studies of the ISM particularly for elemental abundances. Spitzer observations provide a unique perspective on the Ne and S abundances by virtue of observing the dominant ionization states of Ne (Ne+, Ne++) and S (S++, S3+) in Orion and H II regions in general. The Ne/H abundance ratio is especially well determined, with a value of (1.01+/-0.08)E-4. We obtained corresponding new ground-based spectra at CTIO. These optical data are used to estimate the electron temperature, electron density, optical extinction, and the S+/S++ ratio at each of our Spitzer positions. That permits an adjustment for the total gas-phase S abundan...

  2. A spectroscopic binary in the Hercules dwarf spheroidal galaxy

    CERN Document Server

    Koch, Andreas; Feltzing, Sofia; Wilkinson, Mark I

    2013-01-01

    We present the radial velocity curve of a single-lined spectroscopic binary in the faint Hercules dwarf spheroidal (dSph) galaxy, based on 34 individual spectra covering more than two years of observations. This is the first time that orbital elements could be derived for a binary in a dSph. The system consists of a metal-poor red giant and a low-mass companion, possibly a white dwarf, with a 135-days period in a moderately eccentric ($e=0.18$) orbit. Its period and eccentricity are fully consistent with metal-poor binaries in the Galactic halo, while the projected semimajor axis is small, at $a_p$ sin$i$ = 38 R$_{sun}$. In fact, a very close orbit could inhibit the production of heavier elements through $s$-process nucleosynthesis, leading to the very low abundances of neutron-capture elements that are found in this star. We discuss the further implications for the chemical enrichment history of the Hercules dSph, but find no compelling binary scenario that could reasonably explain the full, peculiar abundan...

  3. Molecular line study of evolution in protostellar cloud cores

    CERN Document Server

    Kontinen, S; Heikkilä, A; Haikala, L K

    2000-01-01

    Two dense dark cloud cores representing different stages of dynamical evolution were observed in a number of molecular spectral lines. One of the cores, Cha- MMS1 in the Chamaeleon cloud I contains a Class 0 protostar, whereas the other, CrA C in the R Coronae Australis cloud, is pre-stellar. We find that the cores have very different chemical compositions. Cha-MMS1 exhibits characteristics of so-called `early-type' chemistry with high abundan- ces of carbon-chain molecules such as HC3N, but it also has a large N2H+ abundance, which is expected only to build up at later stages. In contrast, none of the carbon-chain molecules were detected in CrA C. CrA C has a higher SO abundance than Cha-MMS1, which implies that it is chemically `older' than Cha- MMS1. The most striking difference between the two cores is seen in the HC3N/SO abundance ratio, which is at least three orders of magnitude higher in Cha-MMS than in CrA C. This result is surprising since starless cores are usually thought to be chemically younger ...

  4. Cine y experiencia urbana contemporánea

    Directory of Open Access Journals (Sweden)

    José Antonio Cerrillo Vidal

    2009-10-01

    Full Text Available Según la mayor parte de la teoría urbana, la presión que la globalización ejerce sobre la ciudad está acentuando la hegemonía de los espacios puramente funcionales, y con ellos la disolución de las relaciones sociales en su seno. Sin embargo, no abundan los estudios que confirmen este argumento. Dada la tradicional preferencia de las ciencias sociales por la perspectiva macro, la narrativa suele ser la encargada de ocupar este vacío, lo que la convierte en un analizador social de gran utilidad. En este artículo exploro esta posibilidad, analizando tres películas (“Lost in Translation”, “La Terminal” y “Mallrats” que transcurren en espacios típicos de la hipermodernidad (la ciudad global, el aeropuerto, el centro comercial y que representan tres tipos ideales de habitar: trágico, moral-romántico y paródico-popular respectivamente. El objetivo último es replantear el problema de las relaciones urbanas en las sociedades contemporáneas.

  5. Preference for different prey allows the coexistence of several land planarians in areas of the Atlantic Forest.

    Science.gov (United States)

    Boll, Piter Kehoma; Leal-Zanchet, Ana Maria

    2016-06-01

    Land planarians are recognized as important predators, yet studies on their feeding habits are usually restricted to invasive species. Thus, it is difficult to determine the real ecological role of this group in ecosystems and how their communities are structured. In the present study, we analyzed the diet of six co-occurring Neotropical land planarians and their success in capturing prey, based on experiments in the laboratory, in order to determine how they share resources in the same environment. We also calculated indices of food niche breadth and food niche overlap for land planarians for the first time. The diet of Luteostriata abundans comprises only woodlice and the diets of Obama ficki and Obama ladislavii are composed only of gastropods, while Paraba multicolor and Obama anthropophila feed on both gastropods and other land planarians. An invasive species recently found in Western Europe, Obama nungara, showed the highest food niche breadth, feeding on gastropods, earthworms and planarians. We found the highest niche overlap between O. anthropophila and P. multicolor. The results suggest that land planarians are frequent predators of woodlice and land gastropods in the Neotropical ecozone and thus are important for the maintenance of native ecosystems and for the control of invasive species. The coexistence of several species in the same habitat is possible due to the use of different species as main prey, which reduces interspecific competition. PMID:27156235

  6. Las Bellas Artes como Terapia en Aristóteles The Fine Arts as Therapy in Aristotle

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    Sergio González A

    2010-01-01

    Full Text Available Desde Homero en adelante, los textos griegos abundan en menciones a la función terapéutica de las bellas artes. En los diálogos platónicos se encuentra el sistema más acabado respecto a este tema en sus diversas manifestaciones, sin embargo los múltiples análisis aristotélicos se encuentran dispersos y aislados. Para empezar, se expone la visión de la salud como armonía en el pensamiento de Aristóteles, a continuación se describen y comparan los conceptos de tékhne y phrónesis, se demuestra la necesidad del arte para la paideía, y se detalla el uso terapéutico de diferentes artes para preservar o restaurar la salud.From Homer onwards, Greek texts show abundant references to the therapeutic applications of the fine arts. The most complete system dealing with this issue in its diverse manifestations is to be found in the Platonic dialogues. However, Aristotle's manifold analyses are scattered and isolated. First, the view of health as harmony in Aristotle's thought is expounded, then the concepts of tékhne and phrónesis are described and compared, the necessity of art to paideía is demonstrated, and finally the therapeutic use of the different arts in order to preserve or restore health is examined'm detall.

  7. Turismo y contaminación ambiental en la periferia urbana de Acapulco: Ciudad Renacimiento

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    Rocío López Velasco

    2012-01-01

    Full Text Available Nuestro estudio aborda los problemas de sostenibilidad del desarrollo turístico de una ciudad como la de Acapulco, donde se experimenta un desarrollo desigual y excluyente; enfocándonos en los espacios periurbanos donde el deterioro ambiental y la contaminación son consustanciales a la escasez de servicios y a la presencia de pobreza. Ciudad Renacimiento, forma parte del área periurbana de la ciudad y personifica un sector poblacional donde se detectan diferentes fuentes de contaminación. Metodología: se aplicó la técnica: Evaluación Rápida de Fuentes de Contaminación Ambiental (ERFCA para detectar fuentes de contaminación en una zona urbana donde la actividad industrial es incipiente, pero las actividades comerciales y de servicios abundan. Conclusiones: Se constató que el turismo no planeado se convierte en un obstáculo para un desarrollo sustentable; Acapulco es un ejemplo de ello, pues en él se reproducen las asimetrías socioeconómicas que impiden un desarrollo integral. De igual manera, como en otras latitudes, en Acapulco el turismo enfrenta dos alternativas: la sustentabilidad o la modernidad globalizadora, un reto de difícil integración en nuestro país, debido a lapobreza existente y a las dificultades para impulsar un crecimiento equilibrado, el cual es hoy por hoy una prioridad indiscutible.

  8. A transcriptomic analysis of Echinococcus granulosus larval stages: implications for parasite biology and host adaptation.

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    John Parkinson

    Full Text Available BACKGROUND: The cestode Echinococcus granulosus--the agent of cystic echinococcosis, a zoonosis affecting humans and domestic animals worldwide--is an excellent model for the study of host-parasite cross-talk that interfaces with two mammalian hosts. To develop the molecular analysis of these interactions, we carried out an EST survey of E. granulosus larval stages. We report the salient features of this study with a focus on genes reflecting physiological adaptations of different parasite stages. METHODOLOGY/PRINCIPAL FINDINGS: We generated ~10,000 ESTs from two sets of full-length enriched libraries (derived from oligo-capped and trans-spliced cDNAs prepared with three parasite materials: hydatid cyst wall, larval worms (protoscoleces, and pepsin/H(+-activated protoscoleces. The ESTs were clustered into 2700 distinct gene products. In the context of the biology of E. granulosus, our analyses reveal: (i a diverse group of abundant long non-protein coding transcripts showing homology to a middle repetitive element (EgBRep that could either be active molecular species or represent precursors of small RNAs (like piRNAs; (ii an up-regulation of fermentative pathways in the tissue of the cyst wall; (iii highly expressed thiol- and selenol-dependent antioxidant enzyme targets of thioredoxin glutathione reductase, the functional hub of redox metabolism in parasitic flatworms; (iv candidate apomucins for the external layer of the tissue-dwelling hydatid cyst, a mucin-rich structure that is critical for survival in the intermediate host; (v a set of tetraspanins, a protein family that appears to have expanded in the cestode lineage; and (vi a set of platyhelminth-specific gene products that may offer targets for novel pan-platyhelminth drug development. CONCLUSIONS/SIGNIFICANCE: This survey has greatly increased the quality and the quantity of the molecular information on E. granulosus and constitutes a valuable resource for gene prediction on the

  9. Lophotrochozoan mitochondrial genomes

    Energy Technology Data Exchange (ETDEWEB)

    Valles, Yvonne; Boore, Jeffrey L.

    2005-10-01

    Progress in both molecular techniques and phylogeneticmethods has challenged many of the interpretations of traditionaltaxonomy. One example is in the recognition of the animal superphylumLophotrochozoa (annelids, mollusks, echiurans, platyhelminthes,brachiopods, and other phyla), although the relationships within thisgroup and the inclusion of some phyla remain uncertain. While much ofthis progress in phylogenetic reconstruction has been based on comparingsingle gene sequences, we are beginning to see the potential of comparinglarge-scale features of genomes, such as the relative order of genes.Even though tremendous progress is being made on the sequencedetermination of whole nuclear genomes, the dataset of choice forgenome-level characters for many animals across a broad taxonomic rangeremains mitochondrial genomes. We review here what is known aboutmitochondrial genomes of the lophotrochozoans and discuss the promisethat this dataset will enable insight into theirrelationships.

  10. The revised microRNA complement of Fasciola hepatica reveals a plethora of overlooked microRNAs and evidence for enrichment of immuno-regulatory microRNAs in extracellular vesicles.

    Science.gov (United States)

    Fromm, B; Trelis, M; Hackenberg, M; Cantalapiedra, F; Bernal, D; Marcilla, A

    2015-09-01

    MicroRNAs (miRNAs) are gene regulators that have recently been shown to down-regulate the immune response via extracellular vesicles in the mammalian host of helminthic parasites. Using the miRNA prediction pipeline miRCandRef, we expanded the current miRNA set of the liver fluke Fasciola hepatica (Platyhelminthes, Trematoda) from 16 to 54 miRNAs (42 conserved and 13 novel). Comparing the cellular expression levels with extracellular vesicles, we found all miRNAs expressed and enriched for miRNAs with immuno-regulatory function, tissue growth and cancer. Our findings support the hypothesis that miRNAs are the molecular mediators of the previously demonstrated immune modulatory function of extracellular vesicles.

  11. Spatial and temporal variability of mobile macro-invertebrate assemblages associated to coralligenous habitat

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    R. BEDINI

    2014-07-01

    Full Text Available The study aimed to investigate patterns of spatial and temporal variability of mobile macroinvertebrate assemblages associated to coralligenous habitat. A multi-factorial sampling design was used to test the hypotheses that the structure of assemblages and their spatial and temporal variability changed in relation to substrate inclination. Moreover, macroalgae and sessile macro-invertebrates were also investigated in order to detect eventual relationship between sessile and mobile assemblages. A total of 236 mobile macro-invertebrate taxa were identified, among them 2 Platyhelminthes, 4 Sipuncula, 6 Nemertea, 27 Mollusca, 86 Annelida, 103 Arthropoda, 8 Echinodermata. Results of the study showed that mobile macro-invertebrate assemblages of coralligenous habitat were little influenced by the inclination of substrate and by the morphology of sessile organisms, as patterns of variation were different between the two assemblages. Mobile macro-invertebrate assemblages changed among sampling dates within one year period and they showed high variability at the spatial scale examined.

  12. A Fresh Look at Dickinsonia: Removing It from Vendobionta

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xingliang; Joachim REITNER

    2006-01-01

    Abstract: The Ediacaran Dickinsonia is well-known for being the only fossil to be assigned to many phyla, ranging from lichens, Cnidaria, Platyhelminthes, Annelida, and a phylum of its own to a nonmetazoan kingdom. A new specimen from the Ediacaran fine-grained sandstone on the Winter Coast of the White Sea in northern Russia, which has an age of ~555 million years ago, preserved convincing internal anatomies of definite animals, comparable with meridional canals of extant ctenophores (comb jellies). Additionally, we reconsidered Dickinsonia as a biradially symmetrical animal rather than a bilateral one as previously thought. The animal nature of Dickinsonia is, thus, well established and its affinities are most probably allied to ctenophores. This research is not only removing Dickinsonia from Vendobionta, but also bringing the fossil record of ctenophores forward to 20 million years before the Cambrian "explosion".

  13. Why the radiation-attenuated cercarial immunization studies failed to guide the road for an effective schistosomiasis vaccine: A review

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    Rashika El Ridi

    2015-05-01

    Full Text Available Schistosomiasis is a debilitating parasitic disease caused by platyhelminthes of the genus Schistosoma, notably Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum. Pioneer researchers used radiation-attenuated (RA schistosome larvae to immunize laboratory rodent and non-human primate hosts. Significant and reproducible reduction in challenge worm burden varying from 30% to 90% was achieved, providing a sound proof that vaccination against this infection is feasible. Extensive histopathological, tissue mincing and incubation, autoradiographic tracking, parasitological, and immunological studies led to defining conditions and settings for achieving optimal protection and delineating the resistance underlying mechanisms. The present review aims to summarize these findings and draw the lessons that should have guided the development of an effective schistosomiasis vaccine.

  14. Why the radiation-attenuated cercarial immunization studies failed to guide the road for an effective schistosomiasis vaccine: A review.

    Science.gov (United States)

    El Ridi, Rashika; Tallima, Hatem

    2015-05-01

    Schistosomiasis is a debilitating parasitic disease caused by platyhelminthes of the genus Schistosoma, notably Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum. Pioneer researchers used radiation-attenuated (RA) schistosome larvae to immunize laboratory rodent and non-human primate hosts. Significant and reproducible reduction in challenge worm burden varying from 30% to 90% was achieved, providing a sound proof that vaccination against this infection is feasible. Extensive histopathological, tissue mincing and incubation, autoradiographic tracking, parasitological, and immunological studies led to defining conditions and settings for achieving optimal protection and delineating the resistance underlying mechanisms. The present review aims to summarize these findings and draw the lessons that should have guided the development of an effective schistosomiasis vaccine. PMID:26257924

  15. [Retroperitoneal hydatidosis secondary to hepatic hydatid cyst].

    Science.gov (United States)

    Vizcaychipi, Katherina A; Sosa, Sonia; Camicia, Federico; Santillán, Graciela; Casalins, María; Nigro, María Del Carmen

    2012-01-01

    Hydatid disease is a worldwide zoonosis. It is caused by a parasitic platyhelminth of the genus Echinococcus. We present a patient with a fluctuating lumbar tumor in the retroperitoneal space, secondary to a hepatic cyst. the initial diagnosis was made by identification of rostellar hooks from protoscoleces in the fluid aspirated from the abscess. We herein describe the clinical manifestations, diagnosis and medical and surgical treatment of this unusual case and conclude that the development of an accurate diagnosis requires a proper analysis of the patient's epidemiological history, clinical manifestations, imaging studies and laboratory tests. a multidisciplinary approach and differential diagnosis is paramount to be able to establish a cause of the disease to deliver appropriate treatment.

  16. Multigene analysis of lophophorate and chaetognath phylogenetic relationships.

    Science.gov (United States)

    Helmkampf, Martin; Bruchhaus, Iris; Hausdorf, Bernhard

    2008-01-01

    Maximum likelihood and Bayesian inference analyses of seven concatenated fragments of nuclear-encoded housekeeping genes indicate that Lophotrochozoa is monophyletic, i.e., the lophophorate groups Bryozoa, Brachiopoda and Phoronida are more closely related to molluscs and annelids than to Deuterostomia or Ecdysozoa. Lophophorates themselves, however, form a polyphyletic assemblage. The hypotheses that they are monophyletic and more closely allied to Deuterostomia than to Protostomia can be ruled out with both the approximately unbiased test and the expected likelihood weights test. The existence of Phoronozoa, a putative clade including Brachiopoda and Phoronida, has also been rejected. According to our analyses, phoronids instead share a more recent common ancestor with bryozoans than with brachiopods. Platyhelminthes is the sister group of Lophotrochozoa. Together these two constitute Spiralia. Although Chaetognatha appears as the sister group of Priapulida within Ecdysozoa in our analyses, alternative hypothesis concerning chaetognath relationships could not be rejected. PMID:17937996

  17. Venus kinase receptors: prospects in signaling and biological functions of these invertebrate kinases.

    Science.gov (United States)

    Dissous, Colette; Morel, Marion; Vanderstraete, Mathieu

    2014-01-01

    Venus kinase receptors (VKRs) form a family of invertebrate receptor tyrosine kinases (RTKs) initially discovered in the parasitic platyhelminth Schistosoma mansoni. VKRs are single transmembrane receptors that contain an extracellular venus fly trap structure similar to the ligand-binding domain of G protein-coupled receptors of class C, and an intracellular tyrosine kinase domain close to that of insulin receptors. VKRs are found in a large variety of invertebrates from cnidarians to echinoderms and are highly expressed in larval stages and in gonads, suggesting a role of these proteins in embryonic and larval development as well as in reproduction. VKR gene silencing could demonstrate the function of these receptors in oogenesis as well as in spermatogenesis in S. mansoni. VKRs are activated by amino acids and are highly responsive to arginine. As many other RTKs, they form dimers when activated by ligands and induce intracellular pathways involved in protein synthesis and cellular growth, such as MAPK and PI3K/Akt/S6K pathways. VKRs are not present in vertebrates or in some invertebrate species. Questions remain open about the origin of this little-known RTK family in evolution and its role in emergence and specialization of Metazoa. What is the meaning of maintenance or loss of VKR in some phyla or species in terms of development and physiological functions? The presence of VKRs in invertebrates of economical and medical importance, such as pests, vectors of pathogens, and platyhelminth parasites, and the implication of these RTKs in gametogenesis and reproduction processes are valuable reasons to consider VKRs as interesting targets in new programs for eradication/control of pests and infectious diseases, with the main advantage in the case of parasite targeting that VKR counterparts are absent from the vertebrate host kinase panel.

  18. DEMONIOS, PROFETAS Y MÁRTIRES: RESTOS BÍBLICOS EN LA ENSAYÍSTICA HISPANOAMERICANA MODERNA

    Directory of Open Access Journals (Sweden)

    Claudio Maíz

    2013-01-01

    Full Text Available El ensayo nació en Hispanoamérica como un género crítico del colonialismo. El espíritu rebelde que lo caracteriza le ha impedido rendirse ante "verdades reveladas". Esta circunstancia -el espíritu crítico- se ha mantenido a lo largo del tiempo y es la marca que aún hoy lo distingue. En consecuencia, esa característica lo ha alejado de todo dogmatismo (nos referimos desde luego a los ensayos canónicos o que merezcan la categoría de logrados en su forma. Los restos bíblicos en el género no abundan por lo dicho y además como consecuencia de la "sacralización del mundo" que ha ocupado la conciencia americana de nuestros ensayistas. Ello no ha impedido, de todos modos, que el "universo mitológico" del Gran Código (la Biblia del que habla Northrop Frye no penetre los textos de diversos modos. De manera alegórica en algún caso, inconscientemente en otros, pero como estereotipos en la mayoría. Tampoco podemos dejar de aludir a que el Gran Código también afecta la estructura del género ensayístico en cuanto a la praxis profética o redentora en la que los mejores exponentes del género han fusionado radicalmente la idea con la vida.

  19. Icnitas de dinosaurios en Valdelavilla (Soria, España

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    Sanz Pérez, E.

    2000-04-01

    Full Text Available Within the ichnological study of the surroundings of San Pedro Manrique (Soria, Spain, the new site at Valdelavilla, located in unit IV-b of the Huérteles Formation, has yielded dinosaur and pterosaur tracks. The main feature of this site is that it contains a great variety of dinosaur tracks, as regards their type (theropods, omithopods, sauropods their size (from 70 cm to 6 cm, and the way these tracemakers walked (digitigrade, plantigrade. Like many other place at Oncala Group, theropod tracks are abundant, and at a lesser degree, sauropod tracks are also present There is no conclusive evidence of omithopods tracks.Dentro del estudio icnológico que se realiza en los alrededores de San Pedro Manrique (Soria, España el nuevo yacimiento de Valdelavilla, enclavado en la unidad IV-b de la Aloformación Huérteles, ha proporcionado, hasta el momento, huellas de dinosaurios y de pterosaurios. La principal característica del mismo estriba en contener una gran variedad de icnitas de dinosaurios, tanto por su tipo (terópodos, omitópodos, saurópodos, como por su tamaño (desde 70 cm hasta 8 cm y forma de caminar (digitígrados, plantígrados. Como en muchos otros lugares del Grupo Oncala, abundan las huellas de terópodos y en menor proporción las de saurópodos, no presentándose claramente las de omitópodos.

  20. Guillaume Cuchet, director. Le Purgatoire. Fortune historique et historiographique d’un dogme

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    Renán Silva

    2014-03-01

    Full Text Available En Colombia no son tan frecuentes los balances historiográficos, o por lo menos no son tan frecuentes como se desearía —abundan más bien los “estados del arte” en las páginas iniciales de una tesis o de un trabajo de maestría, en general con buena información sobre un tema particular, tratado de manera monográfica—. Pero balances historiográficos, en sentido estricto, es decir trabajos que den cuenta de la totalidad de la investigación en un campo determinado —estudiando con detalle las formas de tratamiento del tema desde el punto de vista de los enfoques, los métodos y las técnicas—, que muestren al mismo tiempo “el ascenso y la caída” de un cierto tema de investigación y la forma de acercamiento dominante en un momento determinado, y que además pongan en relación ese tema particular con el conjunto de la producción historiográfica en un área mayor (aquí, por ejemplo, las historias de las mentalidades y de la cultura y con los avatares mismos de la sociedad de que se trate, ese tipo de balances historiográficos no son frecuentes entre nosotros, y hay que lamentarlo. Le Purgatoire. Fortune historique et historiographique d’ un dogme cumple con creces esa necesidad que señalamos, y puede ser visto grosso modo como un modelo de trabajos que hay que iniciar o continuar, si existen, en muchos campos de la investigación histórica en el país.

  1. The Land of the Dead – International Motifs in the Oldest Work of Japanese Literature

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    Danijela Vasić

    2010-02-01

    Full Text Available Il existe dans le Kojiki (712, la plus ancienne œuvre littéraire du Japon, une abondance de motifs que l’on peut retrouver dans les cultures de nombreux peuples dans le monde entier. Cet article traite des motifs internationaux tissés dans deux mythes du premier tome, formant une image poétique du Pays des morts, la partie souterraine d’une structure cosmique tripartite. Sont abordés, entre autres, le motif largement connu de Perséphone, le motif orphique ou encore le motif de la fuite du Pays des morts.In the Kojiki (712, the oldest literary work of Japan, there is a plethora of motifs which could be found in the cultures of many peoples all over the world. This paper deals with the international motifs interwoven in two myths from the first volume, forming a poetic picture of the Land of the Dead, the underworld part of the trichotomic cosmic structure. Among other things, we find the widely known Persephone motif, the Orphic motif or the motif of the successful escape from the Land of the Dead.En Kojiki (712, la obra literaria más antigua de Japón, abundan motivos que pueden encontrarse en numerosas culturas de todo el mundo. Este artículo analiza los motivos internacionales entretejidos en dos mitos del primer volumen, los cuales forman una imagen poética del País de los Muertos, la sección subterránea de una estructura cósmica tripartita. Se abordan, entre otros, el famoso motivo de Perséfone, el motivo órfico de la huída exitosa del País de los Muertos.

  2. Variación de la vegetación holocena (4300-280 B.P. de Cantabria a traves del análisis polínico de la turbera del Alsa

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    Mariscal, B.

    1993-04-01

    Full Text Available This paper describes the palinological study carried out in a peat deposit in Bárcena Pie de Concha (Cantabria, Spain. A 2,6 m. profile was obtained and 24 samples were studied. Three samples were also dated by 14C. and the ages were also determined (4310 to 280 years B.P.. The data obtained shows that the peat was formed between the Atlantic and the Subboreal, the Subatlantique periods appear well defined in the diagrams. Three phases have been distinguished in the microflora. A inferior section of the profile, characterized by the predominance of Pinus sp. pollen; a second or middle section in which pollen belonging to caducifolium trees, Betula sp. and Corylus avellana, and third or superior section which in characterized by an increase of herbaceous plants, like Ericaceae.Se incluyen los diagramas polínicos con las especies arbóreas y no arbóreas correspondiente a los 2,6 m. de perfil de la turbera, lo que supone el análisis polínico de 24 muestras de turba. Las dataciones absolutas (C-14, obtenidas, muestran que la turbera se formó entre los 4310 y los 280 años B.P. El inicio de la turbera se produce durante la transición entre el período climático Atlántico y el Subboreal, y tanto estos dos períodos como el Subatlántico aparecen bien definidos en el Palinograma. Se han podido diferenciar tres fases en la microflora. Una parte inferior, que se caracteriza por el predominio del polen de Pinus sp.; una parte media en la que abundan los pólenes de árboles caducifolios fundamentalmente Betuna, sp. y Corylus avellana y una parte superior que se caracteriza por un aumento de las plantas herbáceas como Ericaceae.

  3. Geología del complejo volcánico Los Menucos en el área tipo: Río Negro

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    Hebe Lema

    2008-03-01

    Full Text Available Los afloramientos del Complejo volcánico Los Menucos - que cubren una superficie aproximada de 8.000 km² - representan la actividad magmática acontecida durante el Triásico (- Jurásico inferior? en el macizo Norpatagónico. Este complejo está integrado por diversos tipos de depósitos piroclásticos, lavas, diques y cuerpos epizonales a subvolcánicos, y presenta intercalaciones sedimentarias cuyas mejores exposiciones están al oeste de la localidad de Los Menucos. La composición de las rocas volcánicas varía desde leucoriolitas a basandesitas. Los cuerpos son de naturaleza diorítica a monzonítica, con una facies leucogranítica. En un pórfiro monzonítico cuarzoso se obtuvo una edad por isocrona Ar39-Ar40, de 206,9 ± 1,2 Ma. En algunos sectores el espesor mínimo de los depósitos puede estimarse en 2.000 metros, debido fundamentalmente al apilamiento de mantos ignimbríticos, entre los que abundan ignimbritas mesosilícicas con altos porcentajes de cristaloclastos. A partir de un mapeo detallado de litofacies se han reconocido dos áreas que se interpretan como centros de emisión volcánica; otras efusiones están vinculadas a fisuras. La estructura regional se caracteriza por fallas de dimensiones kilométricas, que estuvieron activas durante el magmatismo. Las más importantes tienen rumbo general este-oeste y desplazamientos de rumbo kilométricos, con predominio de una cinemática dextral. Varios rasgos geomórficos que interrumpen la peneplanicie regional están asociados al fallamiento.

  4. Geología del Nunatak Ramírez, Península Jason, Península Antártica Geology of the Ramírez Nunatak, Jason Peninsula, Antarctic Peninsula

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    R.A. del Valle

    2006-09-01

    Full Text Available La sucesión volcánica de 118 m de espesor expuesta en el nunatak Ramírez, península Jason (65°57'S, 60°33'O, península Antártica, está compuesta de una sección inferior donde abundan tobas y areniscas volcánicas, y una sección superior dominada por ignimbritas riolíticas. Los sedimentos volcaniclásticos de la sección inferior contienen moldes de hojas asignadas a Hausmannia de-ferrariisi Feruglio que indica una edad jurásica media. Las rocas del nunatak Ramírez se correlacionan con la Formación Maple de similar edad, la cual aflora típicamente en los alrededores del cabo Disappointment, ubicado a unos 60 km al norte de la península Jason. Estas rocas forman parte de una extensa provincia ígnea silícica desarrollada en Patagonia y la península Antártica en relación con la ruptura de Gondwana.The 118 m thick volcanic sequence exposed at the Ramírez Nunatak, western Jason Peninsula (65°57'S, 60°33'W, Antarctic Peninsula, is composed of a lower section where ash fall tuffs and volcanic sandstones are exposed, and an upper section dominated by rhyolithic ignimbrites. The volcaniclastic sediments of the lower section show imprints of lives assigned to Hausmannia de-ferrariisi Feruglio, which indicates a Mid-Jurassic age. The rocks from Ramírez Nunatak are correlated with Maple Formation of the same age, which is typically exposed at the surroundings of Cape Disappointment, located about 60 km northward from Jason Peninsula. These rocks form part of a siliceous large igneous province developed in Patagonia and Antarctic Peninsula in relation to the Gondwana break-up.

  5. Carlos II: el centenario olvidado

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    Luis Antonio RIBOT GARCÍA

    2009-12-01

    Full Text Available RESUMEN: A partir de una reflexión inicial sobre el fenómeno de las conmemoraciones, el autor se plantea las causas por las que el tercer centenario de la muerte de Carlos II no dará lugar a ninguna conmemoración. Con independencia de las valoraciones de todo tipo que puedan hacerse de dichas celebraciones, lo cierto es que, en este caso, tal vez hubieran permitido acercar al gran público a uno de los monarcas peor conocidos y menos valorados de la historia de España. Lo más grave, sin embargo, es que la sombra del desconocimiento y el juicio peyorativo se extienden también sobre todo su reinado. Las investigaciones sobre aquel periodo, sin embargo, a pesar de que no abundan, muestran una realidad bastante distinta, en la que la decadencia y la pérdida de la hegemonía internacional convivieron con importantes iniciativas y realizaciones políticas, tanto en el ámbito interno de la Monarquía, como en las relaciones internacionales.ABSTRACT: Parting from an initial reflection about the phenomenon of commemorations, the author ponders the causes for which the third centenary of Charles IFs death will not be the subjet of any celebrations. Besides any evaluations which might be made of these events, the truth is that, perhaps, in this case, a commemoration would have brought the general public closer to one of the least known and worst valued monarchs in the history of Spain. What is more serious, however, is the fact that the shadow of ignorance and pejorative judgement extend also over the entirety of his reign. Though scarce, research about this period shows a very different reality, in wich decadence and the loss of international hegemony cohabitated with important political initiatives and achievements, both in the monarchy's internal domain and in the international arena.

  6. Omnivory and resource - sharing in nutrient - deficient Rio Negro waters: stabilization of biodiversity? Omnivoria e repartição de recursos em águas pobres em nutrientes da Bacia do Rio Negro

    Directory of Open Access Journals (Sweden)

    Ilse Walker

    2009-09-01

    Full Text Available Amazonian biodiversity is notorious, this is also valid for the fauna of the mineral-deficient waters of the Rio Negro System. Some 25 years of research on the benthic fauna of Central Amazonian streams resulted in species-rich foodwebs with a high degree of omnivory within dense animal communities. To exemplify the taxonomic range of omnivorous consumers, the detailed resource spectra of 18 consumer species, including Protozoa (2 species, Platyhelminthes (1 species, insects (2 species, fish (6 species and shrimps (Decapoda, 7 species, associated primarily with the benthic habitats of Rio Negro tributaries, are presented. Special features of omnivory are characterized, and the importance of litter-decomposing fungi as essential energy input into the foodwebs is documented. It is shown that general omnivory -diverse omnivore consumers sharing most of the resource types- is a prevalent feature. The relevance of this general omnivory for the maintenance of biodiversity is discussed.A biodiversidade do Amazonas é notório e isto também é válido para as águas pobres em nutrientes da bacia do Rio Negro. Uma pesquisa de 25 anos da fauna béntica de igarapés da Amazônia Central resultou em redes alimentares caraterizadas por alta diversidade de espécies, por intensa omnivoria e por alta densidade populacional. Para demonstrar a generalidade taxonômica de omnivoria no bentos dos igarapés, são apresentados as listas de presas / recursos de 18 espécies de consumidores, sendo Protozoa (2 epécies, Platyhelminthes (1 espécie, insetos (2 espécies, peixes (6 espécies e camarões (Decapoda, 7 espécies. Diferentes categorias de omnivoria são apresentados, e a importância de fungos decompositores da liteira submersa como input básico de energia nas redes alimentares é demonstrada. É prevalente a omnivoria geral, sendo que as diferentes espécies omnívoros estão utilizando os mesmos recursos. Considera- se a relevância desta omnivoria geral

  7. Modular evolution of glutathione peroxidase genes in association with different biochemical properties of their encoded proteins in invertebrate animals

    Directory of Open Access Journals (Sweden)

    Zo Young-Gun

    2009-04-01

    Full Text Available Abstract Background Phospholipid hydroperoxide glutathione peroxidases (PHGPx, the most abundant isoforms of GPx families, interfere directly with hydroperoxidation of lipids. Biochemical properties of these proteins vary along with their donor organisms, which has complicated the phylogenetic classification of diverse PHGPx-like proteins. Despite efforts for comprehensive analyses, the evolutionary aspects of GPx genes in invertebrates remain largely unknown. Results We isolated GPx homologs via in silico screening of genomic and/or expressed sequence tag databases of eukaryotic organisms including protostomian species. Genes showing strong similarity to the mammalian PHGPx genes were commonly found in all genomes examined. GPx3- and GPx7-like genes were additionally detected from nematodes and platyhelminths, respectively. The overall distribution of the PHGPx-like proteins with different biochemical properties was biased across taxa; selenium- and glutathione (GSH-dependent proteins were exclusively detected in platyhelminth and deuterostomian species, whereas selenium-independent and thioredoxin (Trx-dependent enzymes were isolated in the other taxa. In comparison of genomic organization, the GSH-dependent PHGPx genes showed a conserved architectural pattern, while their Trx-dependent counterparts displayed complex exon-intron structures. A codon for the resolving Cys engaged in reductant binding was found to be substituted in a series of genes. Selection pressure to maintain the selenocysteine codon in GSH-dependent genes also appeared to be relaxed during their evolution. With the dichotomized fashion in genomic organizations, a highly polytomic topology of their phylogenetic trees implied that the GPx genes have multiple evolutionary intermediate forms. Conclusion Comparative analysis of invertebrate GPx genes provides informative evidence to support the modular pathways of GPx evolution, which have been accompanied with sporadic

  8. The benthic macroinvertebrate fauna of highland streams in southern Brazil: composition, diversity and structure Fauna de macro-invertebrados bentônicos de rios de montanha no sul do Brasil: composição, diversidade e estrutura

    Directory of Open Access Journals (Sweden)

    Ludwig Buckup

    2007-06-01

    Full Text Available Benthic macroinvertebrate in four rivers, three in the Pelotas River basin (Divisa, Marco and Silveira rivers, in the headwaters of the Uruguai River and one in the Taquari-Antas system (Antas River, a tributary in the Guaíba basin, in the state of Rio Grande do Sul, were identified. Two samples were collected in summer, autumn and spring, with one replicate in each river. The total of 28,961 specimens included members of Platyhelminthes, Annelida, Acarina, Insecta, Crustacea and Mollusca. The Silveira and Marco rivers showed significant differences in the indices of Shannon-Weaver (H’, Simpson’s Reciprocal (1/D, Margalef (DMg and Equitability (E. The Silveira River showed the highest means of diversity and the EPT index (Ephemeroptera, Plecoptera, Trichoptera. Comparison among the diversity indices, considered individually, were insufficient to show differences in community structure, for the purpose of ecological characterization of the rivers. The EPT values characterized the Divisa River as having the highest abundance (73%, followed by the Marco (71%, Antas (48% and Silveira (36%. These results suggest that the Silveira River is subject to moderate environmental stress, from human impact, although it showed the highest diversity of the major macrobenthic groups.Os macro-invertebrados bentônicos que ocorrem em quatro rios, três pertencentes à bacia do Rio Pelotas (Rios Divisa, Marco e Silveira nas cabeceiras do Rio Uruguai e um ao sistema Taquari-Antas (Rio Antas, tributário da bacia do Guaíba, no Estado do Rio Grande do Sul, foram identificados. Duas amostras foram coletadas no verão, outono e primavera, com uma réplica em cada rio. Foram coletados 28961 espécimes de macro-invertebrados compreendendo Platyhelminthes, Annelida, Acarina, Insecta, Crustacea e Mollusca. Na comparação entre os rios, Silveira e Marco mostraram diferenças significativas nos índices de Shannon-Weaver (H’, no Recíproco de Simpson (1/D, de

  9. Purification and kinetic analysis of cytosolic and mitochondrial thioredoxin glutathione reductase extracted from Taenia solium cysticerci.

    Science.gov (United States)

    Plancarte, Agustin; Nava, Gabriela

    2015-02-01

    Thioredoxin glutathione reductases (TGRs) (EC 1.8.1.9) were purified to homogeneity from the cytosolic (cTsTGR) and mitochondrial (mTsTGR) fractions of Taenia solium, the agent responsible for neurocysticercosis, one of the major central nervous system parasitic diseases in humans. TsTGRs had a relative molecular weight of 132,000, while the corresponding value per subunit obtained under denaturing conditions, was of 62,000. Specific activities for thioredoxin reductase and glutathione reductase substrates for both TGRs explored were in the range or lower than values obtained for other platyhelminths and mammalian TGRs. cTsTGR and mTsTGR also showed hydroperoxide reductase activity using hydroperoxide as substrate. Km(DTNB) and Kcat(DTNB) values for cTsTGR and mTsTGR (88 µM and 1.9 s(-1); 45 µM and 12.6 s(-1), respectively) and Km(GSSG) and Kcat(GSSG) values for cTsTGR and mTsTGR (6.3 µM and 0.96 s(-1); 4 µM and 1.62 s(-1), respectively) were similar to or lower than those reported for mammalian TGRs. Mass spectrometry analysis showed that 12 peptides from cTsTGR and seven from mTsTGR were a match for gi|29825896 thioredoxin glutathione reductase [Echinococcus granulosus], confirming that both enzymes are TGRs. Both T. solium TGRs were inhibited by the gold compound auranofin, a selective inhibitor of thiol-dependent flavoreductases (I₅₀ = 3.25, 2.29 nM for DTNB and GSSG substrates, respectively for cTsTGR; I₅₀ = 5.6, 25.4 nM for mTsTGR toward the same substrates in the described order). Glutathione reductase activity of cTsTGR and mTsTGR exhibited hysteretic behavior with moderate to high concentrations of GSSG; this result was not observed either with thioredoxin, DTNB or NADPH. However, the observed hysteretic kinetics was suppressed with increasing amounts of both parasitic TGRs. These data suggest the existence of an effective substitute which may account for the lack of the detoxification enzymes glutathione reductase

  10. Australian spiny mountain crayfish and their temnocephalan ectosymbionts: an ancient association on the edge of coextinction?

    Science.gov (United States)

    Hoyal Cuthill, Jennifer F; Sewell, Kim B; Cannon, Lester R G; Charleston, Michael A; Lawler, Susan; Littlewood, D Timothy J; Olson, Peter D; Blair, David

    2016-05-25

    Australian spiny mountain crayfish (Euastacus, Parastacidae) and their ecotosymbiotic temnocephalan flatworms (Temnocephalida, Platyhelminthes) may have co-occurred and interacted through deep time, during a period of major environmental change. Therefore, reconstructing the history of their association is of evolutionary, ecological, and conservation significance. Here, time-calibrated Bayesian phylogenies of Euastacus species and their temnocephalans (Temnohaswellia and Temnosewellia) indicate near-synchronous diversifications from the Cretaceous. Statistically significant cophylogeny correlations between associated clades suggest linked evolutionary histories. However, there is a stronger signal of codivergence and greater host specificity in Temnosewellia, which co-occurs with Euastacus across its range. Phylogeography and analyses of evolutionary distinctiveness (ED) suggest that regional differences in the impact of climate warming and drying had major effects both on crayfish and associated temnocephalans. In particular, Euastacus and Temnosewellia show strong latitudinal gradients in ED and, conversely, in geographical range size, with the most distinctive, northern lineages facing the greatest risk of extinction. Therefore, environmental change has, in some cases, strengthened ecological and evolutionary associations, leaving host-specific temnocephalans vulnerable to coextinction with endangered hosts. Consequently, the extinction of all Euastacus species currently endangered (75%) predicts coextinction of approximately 60% of the studied temnocephalans, with greatest loss of the most evolutionarily distinctive lineages. PMID:27226467

  11. New perspectives on host-parasite interplay by comparative transcriptomic and proteomic analyses of Schistosoma japonicum.

    Directory of Open Access Journals (Sweden)

    Feng Liu

    2006-04-01

    Full Text Available Schistosomiasis remains a serious public health problem with an estimated 200 million people infected in 76 countries. Here we isolated ~ 8,400 potential protein-encoding cDNA contigs from Schistosoma japonicum after sequencing circa 84,000 expressed sequence tags. In tandem, we undertook a high-throughput proteomics approach to characterize the protein expression profiles of a number of developmental stages (cercariae, hepatic schistosomula, female and male adults, eggs, and miracidia and tissues at the host-parasite interface (eggshell and tegument by interrogating the protein database deduced from the contigs. Comparative analysis of these transcriptomic and proteomic data, the latter including 3,260 proteins with putative identities, revealed differential expression of genes among the various developmental stages and sexes of S. japonicum and localization of putative secretory and membrane antigens, enzymes, and other gene products on the adult tegument and eggshell, many of which displayed genetic polymorphisms. Numerous S. japonicum genes exhibited high levels of identity with those of their mammalian hosts, whereas many others appeared to be conserved only across the genus Schistosoma or Phylum Platyhelminthes. These findings are expected to provide new insights into the pathophysiology of schistosomiasis and for the development of improved interventions for disease control and will facilitate a more fundamental understanding of schistosome biology, evolution, and the host-parasite interplay.

  12. Effect of gamma irradiation on different stages of Fasciola hepatica

    Energy Technology Data Exchange (ETDEWEB)

    Torres, J.L.; Chiriboga, J.

    1976-04-01

    Fascioliasis or hepatic distomatosis is one of the most widespread liver diseases throughout the world. It is caused by a parasitic worm of the class Trematoda of the phylum Platyhelminthes. This flatworm is commonly known as liver-fluke in the United States and Europe; babosa del higado in Cuba; cucaracha del higado in Puerto Rico; saguaype in Argentina and Chile; pirihuin in Chile; yuta in North Chile, and it is taxonomically classified as Fasciola hepatica. The adult trematode is a common parasite of warm blooded animals especially cattle, sheep, and goats. Alterations in the viability of normal Fasciola hepatica metacercariae as a result of time of storage at 4/sup 0/C were studied by the method of Wikerhauser (1960). A significant decrease in viability was observed only after one hundred days of storage. The in vitro viability of normal metacercariae was compared with that of metacercariae that were exposed to increasing ..gamma.. radiation doses. Two plainly opposite effects observed were: the activation of the excystation process by the lower radiation doses (1.5 and 2.5 Kr), an effect that persisted up to the 14th day post-radiation, and the impairment of the process evidenced on the 14th day in the metacercariae exposed to 3.5 and 5.0 Kr. Correlation between liver damage and the increasing radiation doses to which the metacercariae were exposed was studied up to 34 days after the oral inoculation in rats. (auth)

  13. Paragonimus heterotremus Chen and Hsia (1964), in Vietnam: a molecular identification and relationships of isolates from different hosts and geographical origins.

    Science.gov (United States)

    Le, Thanh H; Van De, Nguyen; Blair, David; McManus, Donald P; Kino, Hideto; Agatsuma, Takeshi

    2006-04-01

    Paragonimus heterotremus Chen and Hsia (1964), and paragonimiasis caused by this species is a newly detected disease in Vietnam. Twelve samples of Paragonimus (Platyhelminthes: Trematoda: Digenea: Paragonimidae) from different life-stages (eggs, miracidia, metacercariae, adults from natural and experimental hosts) and host species (crab, dog, cat and human) were collected in different geographical locations in Vietnam. DNA sequences were obtained from each for partial mitochondrial cytochrome c oxidase subunit 1 (cox1) (387 bp) and the entire second ribosomal internal transcribed spacer (ITS-2) (361 bp). The ITS-2 sequences were identical among all specimens, including those previously reported in GenBank. For cox1, there were sequence differences between specimens from Vietnam (four provinces, different locations) and those from Guangxi (China) and Saraburi (Thailand). Phylogenetic trees inferred from cox1 and ITS-2 sequences using sequence data for 15 P. heterotremus and for other Paragonimus spp. revealed that all P. heterotremus originating from Vietnam, Thailand and China form a distinct group. This information also confirms the identity of the Vietnamese specimens as P. heterotremus.

  14. Molecular and biochemical characterization of Paragonimus westermani tyrosinase.

    Science.gov (United States)

    Bae, Y-A; Kim, S-H; Ahn, C-S; Kim, J-G; Kong, Y

    2015-05-01

    Trematode tyrosinases (TYRs) play a major role in the tanning process during eggshell formation. We investigated the molecular and biochemical features of Paragonimus westermani TYR (PwTYR). The PwTYR cDNA was composed of 1568-bp encompassing a 1422-bp-long open reading frame (474-amino acid polypeptide). A strong phylogenetic relationship with Platyhelminthes and Deuterostomian orthologues was evident. The recombinant PwTYR expressed in prokaryotic cells promptly oxidized diphenol substrates, with a preferential affinity toward ortho-positioned hydroxyl groups. It demonstrated fairly weak activity for monophenol compounds. Diphenol oxidase activity was augmented with an increase of pH from 5.0 to 8.0, while monophenol oxidase activity was highest at an acidic pH and gradually decreased as pH increased. Transcription profile of PwTYR was temporally upregulated along with worm development. PwTYR was specifically localized in vitellocytes and eggs. The results suggested that conversion of tyrosine to L-dihydroxyphenylalanine by PwTYR monophenol oxidase activity might be rate-limiting step during the sclerotization process of P. westermani eggs. The pH-dependent pattern of monophenol and diphenol oxidase activity further proposes that the initial hydroxylation might slowly but steadily progress in acidic secreted vesicles of vitellocytes and the second oxidation process might be rapidly accelerated by neural or weak alkaline pH environments within the ootype.

  15. Life cycles, molecular phylogeny and historical biogeography of the 'pygmaeus' microphallids (Digenea: Microphallidae): widespread parasites of marine and coastal birds in the Holarctic.

    Science.gov (United States)

    Galaktionov, Kirill V; Blasco-Costa, Isabel; Olson, Peter D

    2012-09-01

    The 'pygmaeus' microphallids (MPG) are a closely related group of 6 digenean (Platyhelminthes: Trematoda) Microphallus species that share a derived 2-host life cycle in which metacercariae develop inside daughter sporocysts in the intermediate host (intertidal and subtidal gastropods, mostly of the genus Littorina) and are infective to marine birds (ducks, gulls and waders). Here we investigate MPG transmission patterns in coastal ecosystems and their diversification with respect to historical events, host switching and host-parasite co-evolution. Species phylogenies and phylogeographical reconstructions are estimated on the basis of 28S, ITS1 and ITS2 rDNA data and we use a combination of analyses to test the robustness and stability of the results, and the likelihood of alternative biogeographical scenarios. Results demonstrate that speciation within the MPG was not associated with co-speciation with either the first intermediate or final hosts, but rather by host-switching events coincident with glacial cycles in the Northern Hemisphere during the late Pliocene/Pleistocene. These resulted in the expansion of Pacific biota into the Arctic-North Atlantic and periodic isolation of Atlantic and Pacific populations. Thus we hypothesize that contemporary species of MPG and their host associations resulted from fragmentation of populations in regional refugia during stadials, and their subsequent range expansion from refugial centres during interstadials. PMID:22717011

  16. Stem cells and lineages of the intestine: a developmental and evolutionary perspective.

    Science.gov (United States)

    Takashima, Shigeo; Gold, David; Hartenstein, Volker

    2013-03-01

    The intestine consists of epithelial cells that secrete digestive enzymes and mucus (gland cells), absorb food particles (enterocytes), and produce hormones (endocrine cells). Intestinal cells are rapidly turned over and need to be replaced. In cnidarians, mitosis of differentiated intestinal cells accounts for much of the replacement; in addition, migratory, multipotent stem cells (interstitial cells) contribute to the production of intestinal cells. In other phyla, intestinal cell replacement is solely the function of stem cells entering the gut from the outside (such as in case of the neoblasts of platyhelminths) or intestinal stem cells located within the midgut epithelium (as in both vertebrates or arthropods). We will attempt in the following to review important aspects of midgut stem cells in different animal groups: where are they located, what types of lineages do they produce, and how do they develop. We will start out with a comparative survey of midgut cell types found across the animal kingdom; then briefly look at the specification of these cells during embryonic development; and finally focus on the stem cells that regenerate midgut cells during adult life. In a number of model systems, including mouse, zebrafish and Drosophila, the molecular pathways controlling intestinal stem cells proliferation and the specification of intestinal cell types are under intensive investigation. We will highlight findings of the recent literature, focusing on aspects that are shared between the different models and that point at evolutionary ancient mechanisms of intestinal cell formation. PMID:23179635

  17. Зоология = Zoology : учебные тексты : пособие для студентов 1 курса биологического факультета БГУ / [сост. Т. А. Богомолова и др.

    OpenAIRE

    Богомолова, Татьяна Анатольевна

    2009-01-01

    Пособие состоит из 22 текстов, в которых рассматриваются следующие группы животных: Protozoa, Porifera, Coelenterata, Platyhelminthes, Nemathelminthes, Echinodermata, Annelida, Mollusca, Arthropoda, Chordata. Каждый текст включает комплекс упражнений для развития навыков чтения, речи и письма по специальной литературе.

  18. First identification of tetrodotoxin (TTX) in the flatworm Stylochoplana sp.; a source of TTX for the sea slug Pleurobranchaea maculata.

    Science.gov (United States)

    Salvitti, Lauren; Wood, Susanna A; Taylor, David I; McNabb, Paul; Cary, S Craig

    2015-03-01

    High concentrations of the neurotoxin tetrodotoxin (TTX) were detected by liquid chromatography-mass spectrometry (LC-MS) in the Platyhelminthes Stylochoplana sp. from Pilot Bay (Tauranga, New Zealand). This is the first detection of TTX in this genus. Concentrations were monitored from March to November (2013) and found to significantly decrease from a peak in July (avg. 551 mg kg(-1)) to November (avg. 140 mg kg(-1)). Stylochoplana sp. co-occurred with TTX-containing Pleurobranchaea maculata (Opisthobranchia). A Stylochoplana sp.-specific real-time PCR assay was developed targeting the mitochondrial cytochrome c oxidase subunit I gene to determine if P. maculata consumed Stylochoplana sp. Positive Stylochoplana sp. signals were obtained for 7 of 19 P. maculata tested. Mass calculations indicate Stylochoplana sp. could supply Pilot Bay P. maculata with the TTX required to account for the concentrations reported in previous studies (ca. 1.04 mg TTX per individual) based on an ingestion rate of one individual every 2-3 days throughout their lifetime. However, due to the lack of Stylochoplana sp. in areas with dense P. maculata populations, and high concentration (ca. 1400 mg kg(-1)) of TTX detected in some individuals, it is unlikely that Stylochoplana sp. represent the sole source of TTX in P. maculata. PMID:25557071

  19. Biarylalkyl Carboxylic Acid Derivatives as Novel Antischistosomal Agents.

    Science.gov (United States)

    Mäder, Patrick; Blohm, Ariane S; Quack, Thomas; Lange-Grünweller, Kerstin; Grünweller, Arnold; Hartmann, Roland K; Grevelding, Christoph G; Schlitzer, Martin

    2016-07-01

    Parasitic platyhelminths are responsible for serious infectious diseases, such as schistosomiasis, which affect humans as well as animals across vast regions of the world. The drug arsenal available for the treatment of these diseases is limited; for example, praziquantel is the only drug currently used to treat ≥240 million people each year infected with Schistosoma spp., and there is justified concern about the emergence of drug resistance. In this study, we screened biarylalkyl carboxylic acid derivatives for their antischistosomal activity against S. mansoni. These compounds showed significant influence on egg production, pairing stability, and vitality. Tegumental lesions or gut dilatation was also observed. Substitution of the terminal phenyl residue in the biaryl scaffold with a 3-hydroxy moiety and derivatization of the terminal carboxylic acid scaffold with carboxamides yielded compounds that displayed significant antischistosomal activity at concentrations as low as 10 μm with satisfying cytotoxicity values. The present study provides detailed insight into the structure-activity relationships of biarylalkyl carboxylic acid derivatives and thereby paves the way for a new drug-hit moiety for fighting schistosomiasis. PMID:27159334

  20. Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms.

    Directory of Open Access Journals (Sweden)

    Jessica Kathryne Steiner

    2016-05-01

    Full Text Available Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova.

  1. Animal phylogeny and large-scale sequencing: progress and pitfalls%动物系统发育和大规模测序:进展和问题

    Institute of Scientific and Technical Information of China (English)

    Henner BRINKMANN; Hervé PHILIPPE

    2008-01-01

    Phylogenomics, the inference of phylogenetic trees using genome-scale data, is becoming the rule for resolving difficult parts of the tree of life. Its promise resides in the large amount of information available, which should eliminate stochastic error. However, systematic error, which is due to limitations of reconstruction methods, is becoming more apparent. We will illustrate, using animal phylogeny as a case study, the three most efficient approaches to avoid the pitfalls of phylogenomics: (1) using a dense taxon sampling, (2) using probabilistic methods with complex models of sequence evolution that more accurately detect multiple substitutions, and (3) removing the fastest evolving part of the data (e.g., species and positions). The analysis of a dataset of 55 animal species and 102 proteins (25712 amino acid positions) shows that standard site-homogeneous model inference is sensitive to long-branch attraction artifact, whereas the site-heterogeneous CAT model is less so. The latter model correctly locates three very fast evolving species, the appendicularian tunicate Oikopleura, the acoel Convoluta and the myxozoan Buddenbrockia. Overall, the resulting tree is in excellent agreement with the new animal phylogeny, confirming that "simple" organisms like platyhelminths and nematodes are not necessarily of basal emergence. This further emphasizes the importance of secondary simplification in animals, and for organismal evolution in general.

  2. The Global Invertebrate Genomics Alliance (GIGA): Developing Community Resources to Study Diverse Invertebrate Genomes

    KAUST Repository

    Bracken-Grissom, Heather

    2013-12-12

    Over 95% of all metazoan (animal) species comprise the invertebrates, but very few genomes from these organisms have been sequenced. We have, therefore, formed a Global Invertebrate Genomics Alliance (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site () has been launched to facilitate this collaborative venture.

  3. Evolution of neurotransmitter gamma-aminobutyric acid,glutamate and their receptors

    Institute of Scientific and Technical Information of China (English)

    Zhiheng GOU; Xiao WANG; Wen WANG

    2012-01-01

    Gamma-aminobutyric acid (GABA) and glutamate are two important amino acid neurotransmitters widely present in the nervous systems of ammals,insects,round worm,and platyhelminths,while their receptors are quite diversified across different animal phyla.However,the evolutionary mechanisms between the two conserved neurotransmitters and their diversified receptors remain elusive,and antagonistic interactions between GABA and glutamate signal transduction systems,in particular,have begun to attract significant attention.In this review,we summarize the extant results on the origin and evolution of GABA and glutamate,as well as their receptors,and analyze possible evolutionary processes and phylogenetic relationships of various GABAs and glutamate receptors.We further discuss the evolutionary history of Excitatory/Neutral Amino Acid Transporter (EAAT),a transport protein,which plays an important role in the GABA-glutamate "yin and yang" balanced regulation.Finally,based on current advances,we propose several potential directions of future research.

  4. Host and ecology both play a role in shaping distribution of digenean parasites of New Zealand whelks (Gastropoda: Buccinidae: Cominella).

    Science.gov (United States)

    Donald, Kirsten M; Spencer, Hamish G

    2016-08-01

    Digenean parasites infecting four Cominella whelk species (C. glandiformis, C. adspersa, C. maculosa and C. virgata), which inhabit New Zealand's intertidal zone, were analysed using molecular techniques. Mitochondrial 16S and cytochrome oxidase 1 (COI) and nuclear rDNA ITS1 sequences were used to infer phylogenetic relationships amongst digenea. Host species were parasitized by a diverse range of digenea (Platyhelminthes, Trematoda), representing seven families: Echinostomatidae, Opecoelidae, Microphallidae, Strigeidae and three, as yet, undetermined families A, B and C. Each parasite family infected between one and three host whelk species, and infection levels were typically low (average infection rates ranged from 1·4 to 3·6%). Host specificity ranged from highly species-specific amongst the echinostomes, which were only ever observed infecting C. glandiformis, to the more generalist opecoelids and strigeids, which were capable of infecting three out of four of the Cominella species analysed. Digeneans displayed a highly variable geographic range; for example, echinostomes had a large geographic range stretching the length of New Zealand, from Northland to Otago, whereas Family B parasites were restricted to fairly small areas of the North Island. Our results add to a growing body of research identifying wide ranges in both host specificity and geographic range amongst intertidal, multi-host parasite systems. PMID:27278710

  5. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites.

    Science.gov (United States)

    Biswal, Devendra Kumar; Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php.

  6. Quo Vadis Venomics? A Roadmap to Neglected Venomous Invertebrates

    Directory of Open Access Journals (Sweden)

    Bjoern Marcus von Reumont

    2014-12-01

    Full Text Available Venomics research is being revolutionized by the increased use of sensitive -omics techniques to identify venom toxins and their transcripts in both well studied and neglected venomous taxa. The study of neglected venomous taxa is necessary both for understanding the full diversity of venom systems that have evolved in the animal kingdom, and to robustly answer fundamental questions about the biology and evolution of venoms without the distorting effect that can result from the current bias introduced by some heavily studied taxa. In this review we draw the outlines of a roadmap into the diversity of poorly studied and understood venomous and putatively venomous invertebrates, which together represent tens of thousands of unique venoms. The main groups we discuss are crustaceans, flies, centipedes, non-spider and non-scorpion arachnids, annelids, molluscs, platyhelminths, nemerteans, and echinoderms. We review what is known about the morphology of the venom systems in these groups, the composition of their venoms, and the bioactivities of the venoms to provide researchers with an entry into a large and scattered literature. We conclude with a short discussion of some important methodological aspects that have come to light with the recent use of new -omics techniques in the study of venoms.

  7. Two new species of Urocleidoides Mizelle et Price, 1964 (Monogenoidea) from the gill lamellae of profundulids and poeciliids from Central America and southern Mexico.

    Science.gov (United States)

    Mendoza-Franco, Edgar F; Caspeta-Mandujano, Juan Manuel; Salgado-Maldonado, Guillermo; Matamoros, Wilfredo Antonio

    2015-01-01

    During investigations of gill ectoparasites (Platyhelminthes) parasitising freshwater fish from Central America (Guatemala, Honduras, El Salvador and Panama) and southeastern Mexico (Guerrero, Oaxaca and Chiapas), the following dactylogyrid monogenoidean were found: Urocleidoides simonae sp. n. from Profundulus punctatus (Günther) (type host), Profundulus balsanus Ahl, Profundulus guatemalensis (Günther), Profundulus kreiseri Matamoros, Shaefer, Hernández et Chakrabarty, Profundulus labialis (Günther), Profundulus oaxacae (Meek), Profundulus sp. 1 and Profundulus sp. 2 (all Profundulidae); Urocleidoides vaginoclaustroides sp. n. from Pseudoxiphophorus bimaculata (Heckel) (type host) and Poeciliopsis retropinna (Regan) (both Poeciliidae); and Urocleidoides vaginoclaustrum Jogunoori, Kritsky et Venkatanarasaiah, 2004 from P. labialis, Profundulus portillorum Matamoros et Shaefer and Xiphophorus hellerii Heckel (Poeciliidae). Urocleidoides simonae sp. n. differs from all other congeneric species in having anchors with well-differentiated roots, curved elongate shaft and short point. Urocleidoides vaginoclaustroides sp. n. most closely resembles U. vaginoclaustrum, but differs from this species mainly in the shape of its anchors (i.e. evenly curved shaft and short point vs curved shaft and elongate point extending just past the tip of the superficial anchor root). The complexity of potential hosts for species of Urocleidoides and their effect on its distribution on profundulid and poeciliid fishes are briefly discussed. PMID:26580223

  8. Mixed infections and hybridisation in monogenean parasites.

    Directory of Open Access Journals (Sweden)

    Bettina Schelkle

    Full Text Available Theory predicts that sexual reproduction promotes disease invasion by increasing the evolutionary potential of the parasite, whereas asexual reproduction tends to enhance establishment success and population growth rate. Gyrodactylid monogeneans are ubiquitous ectoparasites of teleost fish, and the evolutionary success of the specious Gyrodactylus genus is thought to be partly due to their use of various modes of reproduction. Gyrodactylus turnbulli is a natural parasite of the guppy (Poecilia reticulata, a small, tropical fish used as a model for behavioural, ecological and evolutionary studies. Using experimental infections and a recently developed microsatellite marker, we conclusively show that monogenean parasites reproduce sexually. Conservatively, we estimate that sexual recombination occurs and that between 3.7-10.9% of the parasites in our experimental crosses are hybrid genotypes with ancestors from different laboratory strains of G. turnbulli. We also provide evidence of hybrid vigour and/or inter-strain competition, which appeared to lead to a higher maximum parasite load in mixed infections. Finally, we demonstrate inbreeding avoidance for the first time in platyhelminths which may influence the distribution of parasites within a host and their subsequent exposure to the host's localized immune response. Combined reproductive modes and inbreeding avoidance may explain the extreme evolutionary diversification success of parasites such as Gyrodactylus, where host-parasite coevolution is punctuated by relatively frequent host switching.

  9. Northeast India Helminth Parasite Information Database (NEIHPID): Knowledge Base for Helminth Parasites.

    Science.gov (United States)

    Biswal, Devendra Kumar; Debnath, Manish; Kharumnuid, Graciously; Thongnibah, Welfrank; Tandon, Veena

    2016-01-01

    Most metazoan parasites that invade vertebrate hosts belong to three phyla: Platyhelminthes, Nematoda and Acanthocephala. Many of the parasitic members of these phyla are collectively known as helminths and are causative agents of many debilitating, deforming and lethal diseases of humans and animals. The North-East India Helminth Parasite Information Database (NEIHPID) project aimed to document and characterise the spectrum of helminth parasites in the north-eastern region of India, providing host, geographical distribution, diagnostic characters and image data. The morphology-based taxonomic data are supplemented with information on DNA sequences of nuclear, ribosomal and mitochondrial gene marker regions that aid in parasite identification. In addition, the database contains raw next generation sequencing (NGS) data for 3 foodborne trematode parasites, with more to follow. The database will also provide study material for students interested in parasite biology. Users can search the database at various taxonomic levels (phylum, class, order, superfamily, family, genus, and species), or by host, habitat and geographical location. Specimen collection locations are noted as co-ordinates in a MySQL database and can be viewed on Google maps, using Google Maps JavaScript API v3. The NEIHPID database has been made freely available at http://nepiac.nehu.ac.in/index.php. PMID:27285615

  10. A checklist of helminth parasites of Elasmobranchii in Mexico.

    Science.gov (United States)

    Merlo-Serna, Aldo Iván; García-Prieto, Luis

    2016-01-01

    A comprehensive and updated summary of the literature and unpublished records contained in scientific collections on the helminth parasites of the elasmobranchs from Mexico is herein presented for the first time. At present, the helminth fauna associated with Elasmobranchii recorded in Mexico is composed of 132 (110 named species and 22 not assigned to species), which belong to 70 genera included in 27 families (plus 4 incertae sedis families of cestodes). These data represent 7.2% of the worldwide species richness. Platyhelminthes is the most widely represented, with 128 taxa: 94 of cestodes, 22 of monogeneans and 12 of trematodes; Nematoda and Annelida: Hirudinea are represented by only 2 taxa each. These records come from 54 localities, pertaining to 15 states; Baja California Sur (17 sampled localities) and Baja California (10), are the states with the highest species richness: 72 and 54 species, respectively. Up to now, 48 elasmobranch species have been recorded as hosts of helminths in Mexico; so, approximately 82% of sharks and 67% of rays distributed in Mexican waters lack helminthological studies. The present list provides the host, distribution (with geographical coordinates), site of infection, accession number in scientific collections, and references for the parasites. A host-parasite list is also provided. PMID:27047240

  11. Macroinvertebrates of the Iranian running waters: a review

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    Moslem Sharifinia

    2015-12-01

    Full Text Available Abstract A comprehensive review of macroinvertebrate studies conducted along the Iranian running waters over the last 15 years has been made by providing the most updated checklist of the Iranian running waters benthic invertebrates. Running waters ecosystems are complex environments known for their importance in terms of biodiversity. As part of the analysis, we endeavored to provide the critical re-identification of the reported species by through comparisons with the database of the Animal Diversity Web (ADW and appropriate literature sources or expert knowledge. A total of 126 species belonging to 4 phyla have been compiled from 57 references. The phylum Arthropoda was found to comprise the most taxa (n = 104 followed by Mollusca, Annelida and Platyhelminthes. Ongoing efforts in the Iranian running waters regarding biomonitoring indices development, testing, refinement and validation are yet to be employed in streams and rivers. Overall, we suggest that future macroinvertebrate studies in Iranian running waters should be focused on long-term changes by broadening target species and strong efforts to publish data in peer-reviewed journals in English.

  12. Drivers of parasite sharing among Neotropical freshwater fishes.

    Science.gov (United States)

    Braga, Mariana P; Razzolini, Emanuel; Boeger, Walter A

    2015-03-01

    Because host-parasite interactions are so ubiquitous, it is of primary interest for ecologists to understand the factors that generate, maintain and constrain these associations. Phylogenetic comparative studies have found abundant evidence for host-switching to relatively unrelated hosts, sometimes related to diversification events, in a variety of host-parasite systems. For Monogenoidea (Platyhelminthes) parasites, it has been suggested that the co-speciation model alone cannot explain host occurrences, hence host-switching and/or non-vicariant modes of speciation should be associated with the origins and diversification of several monogenoid taxa. The factors that shape broad patterns of parasite sharing were investigated using path analysis as a way to generate hypotheses about the origins of host-parasite interactions between monogenoid gill parasites and Neotropical freshwater fishes. Parasite sharing was assessed from an interaction matrix, and explanatory variables included phylogenetic relationships, environmental preferences, biological traits and geographic distribution for each host species. Although geographic distribution of hosts and host ecology are important factors to understand host-parasite interactions, especially within host lineages that share a relatively recent evolutionary history, phylogeny had the strongest overall direct effect on parasite sharing. Phylogenetic contiguity of host communities may allow a 'stepping-stone' mode of host-switching, which increases parasite sharing. Our results reinforce the importance of including evolutionary history in the study of ecological associations, including emerging infectious diseases risk assessment.

  13. Planarians Sense Simulated Microgravity and Hypergravity

    Directory of Open Access Journals (Sweden)

    Teresa Adell

    2014-01-01

    Full Text Available Planarians are flatworms, which belong to the phylum Platyhelminthes. They have been a classical subject of study due to their amazing regenerative ability, which relies on the existence of adult totipotent stem cells. Nowadays they are an emerging model system in the field of developmental, regenerative, and stem cell biology. In this study we analyze the effect of a simulated microgravity and a hypergravity environment during the process of planarian regeneration and embryogenesis. We demonstrate that simulated microgravity by means of the random positioning machine (RPM set at a speed of 60 °/s but not at 10 °/s produces the dead of planarians. Under hypergravity of 3 g and 4 g in a large diameter centrifuge (LDC planarians can regenerate missing tissues, although a decrease in the proliferation rate is observed. Under 8 g hypergravity small planarian fragments are not able to regenerate. Moreover, we found an effect of gravity alterations in the rate of planarian scission, which is its asexual mode of reproduction. No apparent effects of altered gravity were found during the embryonic development.

  14. Phylogeny and mitochondrial gene order variation in Lophotrochozoa in the light of new mitogenomic data from Nemertea

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    von Döhren Jörn

    2009-08-01

    Full Text Available Abstract Background The new animal phylogeny established several taxa which were not identified by morphological analyses, most prominently the Ecdysozoa (arthropods, roundworms, priapulids and others and Lophotrochozoa (molluscs, annelids, brachiopods and others. Lophotrochozoan interrelationships are under discussion, e.g. regarding the position of Nemertea (ribbon worms, which were discussed to be sister group to e.g. Mollusca, Brachiozoa or Platyhelminthes. Mitochondrial genomes contributed well with sequence data and gene order characters to the deep metazoan phylogeny debate. Results In this study we present the first complete mitochondrial genome record for a member of the Nemertea, Lineus viridis. Except two trnP and trnT, all genes are located on the same strand. While gene order is most similar to that of the brachiopod Terebratulina retusa, sequence based analyses of mitochondrial genes place nemerteans close to molluscs, phoronids and entoprocts without clear preference for one of these taxa as sister group. Conclusion Almost all recent analyses with large datasets show good support for a taxon comprising Annelida, Mollusca, Brachiopoda, Phoronida and Nemertea. But the relationships among these taxa vary between different studies. The analysis of gene order differences gives evidence for a multiple independent occurrence of a large inversion in the mitochondrial genome of Lophotrochozoa and a re-inversion of the same part in gastropods. We hypothesize that some regions of the genome have a higher chance for intramolecular recombination than others and gene order data have to be analysed carefully to detect convergent rearrangement events.

  15. Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms.

    Science.gov (United States)

    Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

    2016-05-01

    Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova. PMID:27149082

  16. Drivers of parasite sharing among Neotropical freshwater fishes.

    Science.gov (United States)

    Braga, Mariana P; Razzolini, Emanuel; Boeger, Walter A

    2015-03-01

    Because host-parasite interactions are so ubiquitous, it is of primary interest for ecologists to understand the factors that generate, maintain and constrain these associations. Phylogenetic comparative studies have found abundant evidence for host-switching to relatively unrelated hosts, sometimes related to diversification events, in a variety of host-parasite systems. For Monogenoidea (Platyhelminthes) parasites, it has been suggested that the co-speciation model alone cannot explain host occurrences, hence host-switching and/or non-vicariant modes of speciation should be associated with the origins and diversification of several monogenoid taxa. The factors that shape broad patterns of parasite sharing were investigated using path analysis as a way to generate hypotheses about the origins of host-parasite interactions between monogenoid gill parasites and Neotropical freshwater fishes. Parasite sharing was assessed from an interaction matrix, and explanatory variables included phylogenetic relationships, environmental preferences, biological traits and geographic distribution for each host species. Although geographic distribution of hosts and host ecology are important factors to understand host-parasite interactions, especially within host lineages that share a relatively recent evolutionary history, phylogeny had the strongest overall direct effect on parasite sharing. Phylogenetic contiguity of host communities may allow a 'stepping-stone' mode of host-switching, which increases parasite sharing. Our results reinforce the importance of including evolutionary history in the study of ecological associations, including emerging infectious diseases risk assessment. PMID:25283218

  17. Presence of galactosylated core fucose on N-glycans in the planaria Dugesia japonica.

    Science.gov (United States)

    Paschinger, Katharina; Razzazi-Fazeli, Ebrahim; Furukawa, Kiyoshi; Wilson, Iain B H

    2011-06-01

    Planarial species are of especial interest to biologists due to the phenomenon of pluripotency and, in comparison to other developmental processes, it can be hypothesised that glycan-lectin interactions may play a role. In order to examine the N-glycans of one of these organisms, Dugesia japonica, peptide:N-glycosidase A was employed and the released glycans were subject to pyridylamination, HPLC and mass spectrometric analysis. A range of oligomannosidic glycans was observed with a trimethylated Man(5) GlcNAc(2) structure being the dominant species. Three glycans were also observed to contain deoxyhexose; in particular, a glycan with the composition Hex(4) HexNAc(2) Fuc(1) Me(2) was revealed by exoglycosidase digestion, in combination with MS/MS, to contain a galactosylated core α1,6-fucose residue, whereas this core modification was found to be capped with a methylhexose residue in the case of a Hex(5) HexNAc(2) Fuc(1) Me(3) structure. This is the first report of these types of structures in a platyhelminth and indicates that the 'GalFuc' modification of N-glycans is not just restricted to molluscs and nematodes.

  18. Gnathostomulida--an enigmatic metazoan phylum from both morphological and molecular perspectives.

    Science.gov (United States)

    Littlewood, D T; Telford, M J; Clough, K A; Rohde, K

    1998-02-01

    On the basis of few and contentious morphological characters Gnathostomulids have been thought to be the sister-group of either the Platyhelminthes or the Syndermata (Rotifera + Acanthocephala). We provide a full 18S rDNA sequence for a species of Gnathostomula and attempt to resolve its position among the Metazoa, on the basis of molecular evidence. Sixty sequences, representing 30 nominal phyla and including new entoproct and gastrotrich sequences, were used to reconstruct phylogenies using maximum-parsimony, neighbor-joining, and minimum evolution models. We were unable to support either of the morphological hypotheses outright and, moreover, our data supported more strongly a third possible relationship with the gnathostomulids as a member of the Nematoda + Chaetognatha clade. Superficially, as active benthic, vermiform creatures with sclerotized cuticular jaws, they fit a predicted ancestral form of the Nematoda + Chaetognatha clade and, as such, would arguably be members of the Ecdysozoa. The molecular data at least call for a reevaluation of the morphological data and a denser sampling of the lesser phyla. Data from morphology and molecules act synergistically in estimating phylogeny; morphology alone provided limited phylogenetic signal and alternative phylogenetic hypotheses, whereas the molecular solution suggested an alternative topology which, when interpreted in the light of comparative anatomy, may suggest previously unconsidered possibilities. PMID:9479696

  19. A Review of Myxosporea, Microspora and Monogenea Infections in African Fish

    Directory of Open Access Journals (Sweden)

    J.F.N. Abowei

    2011-11-01

    Full Text Available Myxosporea, Microspora and Monogenea infections in African fish was reviewed to educate fish culturists on some potential challenges in culture fisheries management. The description, taxonomy and diagnosis, Pathology, Life cycle and biology, Epizootiology and Control of Myxosporea, Microspora and Monogenea in African fish was reviewed to educate fish culturist on more challenges faced in culture fisheries. Myxoporidea is a class of protozoa which parasitize invertebrates and lower vertebrates particularly fish, often fatal consequences for the host. Microspora consists of simpler spores and are of unicellular origin. They occur in animals of most phyla, but are most commonly found in insects and fishes, where they multiply in the host cells and cause hypertrophy of host tissues. Monogenea is a class of the phylum platyhelminthes commonly found on the skin and gills of marine and fresh water fishes. The worms are characterized by an opistohaopor. The life cycle is Monoxenous. They are hermaphrodites and mainly ectoparasites though a few are known to be endoparasites. These parasites are problem to culture fisheries causing fish mortality.

  20. Effect of Donepezil, Tacrine, Galantamine and Rivastigmine on Acetylcholinesterase Inhibition in Dugesia tigrina

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    Cristiane Bezerra da Silva

    2016-01-01

    Full Text Available Dugesia tigrina is a non-parasitic platyhelminth, which has been recently utilized in pharmacological models, regarding the nervous system, as it presents a wide sensitivity to drugs. Our trials aimed to propose a model for an in vivo screening of substances with inhibitory activity of the enzyme acetylcholinesterase. Trials were performed with four drugs commercialized in Brazil: donepezil, tacrine, galantamine and rivastigmine, utilized in the control of Alzheimer’s disease, to inhibit the activity of acetylcholinesterase. We tested five concentrations of the drugs, with an exposure of 24 h, and the mortality and the inhibition of acetylcholinesterase planarian seizure-like activity (pSLA and planarian locomotor velocity (pLMV were measured. Galantamine showed high anticholinesterasic activity when compared to the other drugs, with a reduction of 0.05 μmol·min−1 and 63% of convulsant activity, presenting screw-like movement and hypokinesia, with pLMV of 65 crossed lines during 5 min. Our results showed for the first time the anticholinesterasic and convulsant effect, in addition to the decrease in locomotion induced by those drugs in a model of invertebrates. The experimental model proposed is simple and low cost and could be utilized in the screening of substances with anticholinesterasic action.

  1. Complete Mitochondrial Genome of Haplorchis taichui and Comparative Analysis with Other Trematodes

    Science.gov (United States)

    Lee, Dongmin; Choe, Seongjun; Park, Hansol; Jeon, Hyeong-Kyu; Chai, Jong-Yil; Sohn, Woon-Mok; Yong, Tai-Soon; Min, Duk-Young; Rim, Han-Jong

    2013-01-01

    Mitochondrial genomes have been extensively studied for phylogenetic purposes and to investigate intra- and interspecific genetic variations. In recent years, numerous groups have undertaken sequencing of platyhelminth mitochondrial genomes. Haplorchis taichui (family Heterophyidae) is a trematode that infects humans and animals mainly in Asia, including the Mekong River basin. We sequenced and determined the organization of the complete mitochondrial genome of H. taichui. The mitochondrial genome is 15,130 bp long, containing 12 protein-coding genes, 2 ribosomal RNAs (rRNAs, a small and a large subunit), and 22 transfer RNAs (tRNAs). Like other trematodes, it does not encode the atp8 gene. All genes are transcribed from the same strand. The ATG initiation codon is used for 9 protein-coding genes, and GTG for the remaining 3 (nad1, nad4, and nad5). The mitochondrial genome of H. taichui has a single long non-coding region between trnE and trnG. H. taichui has evolved as being more closely related to Opisthorchiidae than other trematode groups with maximal support in the phylogenetic analysis. Our results could provide a resource for the comparative mitochondrial genome analysis of trematodes, and may yield genetic markers for molecular epidemiological investigations into intestinal flukes. PMID:24516279

  2. Harnessing the Toxocara Genome to Underpin Toxocariasis Research and New Interventions.

    Science.gov (United States)

    Gasser, Robin B; Korhonen, Pasi K; Zhu, Xing-Quan; Young, Neil D

    2016-01-01

    Parasitic worms, such as flatworms (platyhelminths) and roundworms (nematodes), cause substantial morbidity and mortality in animals and people globally. The ascaridoid nematode Toxocara canis is a zoonotic parasite of socioeconomic significance worldwide. In humans, this worm causes toxocariasis (disease) mainly in underprivileged communities in both the developed and developing worlds. While reasonably well studied from clinical and epidemiological perspectives, little is understood about the molecular biology of T. canis, its relationship with its hosts and the disease that it causes. However, a recent report of the draft genome and transcriptomes of T. canis should underpin many fundamental and applied research areas in the future. The present article gives a background on Toxocara and toxocariasis, a brief account of diagnostic approaches for specific identification and genetic analysis, and gives a perspective on the impact that the genome of T. canis and advanced molecular technologies could have on our understanding of the parasite and the diseases that it causes as well as the design of new and improved approaches for the diagnosis, treatment and control of toxocariasis. PMID:27015948

  3. Macrofauna associated to Mycale microsigmatosa (Porifera, Demospongiae) in Rio de Janeiro State, SE Brazil

    Science.gov (United States)

    Ribeiro, Suzi M.; Omena, Elianne P.; Muricy, Guilherme

    2003-08-01

    The macrofauna (endo- and epi-biotic) associated to the sponge Mycale ( Carmia) microsigmatosa Arndt, 1927 was studied at three sites in Rio de Janeiro State, Brazil (Arraial do Cabo, Niterói, and Rio de Janeiro). A total of 2235 individuals (over 1 mm long) of 75 invertebrate species were found associated to 19 specimens of the sponge. The most abundant and diverse taxa were the crustaceans (83%, 31 spp.), polychetes (10%, 18 spp.), and molluscs (3.7%, 15 spp.). Cnidarians, platyhelminthes, ascidians, echinoderms, pycnogonids, bryozoans, and sponges were also represented. Amphipod crustaceans were the dominant group, comprising 61% of all individuals collected. Species richness and abundance of associated fauna were highly correlated with sponge volume, but diversity and evenness were not. The site of collection influenced the species composition of the fauna associated to M. microsigmatosa but did not change significantly its diversity, abundance, richness, and dominance patterns of higher taxa. Pregnant females and juvenile stages of 29% of the species associated, including crustaceans, molluscs, echinoderms, and pycnogonids were frequently found inside M. microsigmatosa. Although many of these organisms do occur and reproduce in other habitats outside the sponge as well, M. microsigmatosa is also important for their reproduction and survivorship, thus contributing for the maintenance of biodiversity in Southwestern Atlantic sublittoral rocky shores.

  4. HelmCoP: an online resource for helminth functional genomics and drug and vaccine targets prioritization.

    Directory of Open Access Journals (Sweden)

    Sahar Abubucker

    Full Text Available A vast majority of the burden from neglected tropical diseases result from helminth infections (nematodes and platyhelminthes. Parasitic helminthes infect over 2 billion, exerting a high collective burden that rivals high-mortality conditions such as AIDS or malaria, and cause devastation to crops and livestock. The challenges to improve control of parasitic helminth infections are multi-fold and no single category of approaches will meet them all. New information such as helminth genomics, functional genomics and proteomics coupled with innovative bioinformatic approaches provide fundamental molecular information about these parasites, accelerating both basic research as well as development of effective diagnostics, vaccines and new drugs. To facilitate such studies we have developed an online resource, HelmCoP (Helminth Control and Prevention, built by integrating functional, structural and comparative genomic data from plant, animal and human helminthes, to enable researchers to develop strategies for drug, vaccine and pesticide prioritization, while also providing a useful comparative genomics platform. HelmCoP encompasses genomic data from several hosts, including model organisms, along with a comprehensive suite of structural and functional annotations, to assist in comparative analyses and to study host-parasite interactions. The HelmCoP interface, with a sophisticated query engine as a backbone, allows users to search for multi-factorial combinations of properties and serves readily accessible information that will assist in the identification of various genes of interest. HelmCoP is publicly available at: http://www.nematode.net/helmcop.html.

  5. Sistemas agroecológicos y su papel en los países del Tercer Mundo

    Directory of Open Access Journals (Sweden)

    F. Funes-Aguilar

    2006-01-01

    Full Text Available El tercer milenio inicia en un mundo globalizado, unipolar: 6.3 mil millones de personas; de ellas, 850 millones hambrientas, 1,200 sin agua potable, 2,400 sin saneamiento, 850 millones analfabetos, 10 millones de niños mueren anualmente. Mientras tanto, 10% de la población disfruta del 70% de riquezas. Proliferan estallidos sociales, guerras, huracanes, terremotos, contaminación ambiental, inundaciones, calentamiento global, SIDA. Numerosas comunidades rurales se han colapsado económica y socialmente, el desempleo aumenta por tecnologías ahorradoras de fuerza laboral, persiste alta migración a las ciudades. La “Revolución Verde”, de especialización e industrialización agropecuaria de países desarrollados, ha generado conflictos ambientales y no ha sido una solución. La geofagia y sed de poder de países y políticos, generan distribución desequilibrada de riquezas. En nuestro planeta abundan resultados positivos con sistemas agroecológicos de producción que han demostrado poder resolver gran número de esos problemas. En América Latina y Cuba, existen experiencias del saber y tradiciones campesinas e indígenas, investigación y producción comercial con soluciones factibles para los problemas de este llamado “Tercer Mundo”, donde están los países más necesitados. Son evidentes los caminos posibles para alcanzar el anhelado desarrollo agropecuario. Este trabajo resume algunos ejemplos de los avances. El reto futuro es integrar los componentes de los agroecosistemas y lograr sinergias, consolidando sistemas agroecológicos holísticos, con eficiencia biológica, productiva, económica, energética y ambiental. Es esperanzador pensar que un futuro agroecológico unido a la voluntad política de desarrollo económico y social, puede contribuir en alto grado a liberar a nuestros países tercermundistas de la crítica situación actual

  6. Algunas observaciones entomológicas relacionadas con el paludismo en Lima

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    Alberto Cornejo Donayre

    1944-09-01

    Full Text Available Hemos encontrado que de las dos especies de Anopheles, A. pseudopunctipennis y A. punctimacula presentes en los Valles del Rímac y del Santa Eulalia, el pseudopunctipennis sería el trasmisor responsable de la elevada morbilidad palúdica existente en estos valles, ya que sus criaderos se hallan cercanos a los lugares poblados (en ocasiones solo a unos metros, porque los zancudos adultos tienen marcados hábitos domésticos, pues en considerable número se les encuentra en el interior de las habitaciones humanas; y sobre todo porque en las disecciones practicadas se verificó que el porcentaje con infección natural está dentro de los límites señalados para las localidades donde el paludismo es común. El tipo de criadero preferido por el A. pseudopunctipennis, está constituido por colecciones de agua limpia existentes entre las piedras situadas a pocos metros de las márgenes del río, criaderos que abundan cuando el río disminuye su caudal. Estos criaderos tienen en su superficie gran cantidad de algas verdes y por lo general están directamente expuestos al sol. Se verificó que en los alrededores de la ciudad de Lima, el A. pseudopunctipennis se reproduce durante los meses del otoño e invierno en este mismo tipo de criaderos ( 1 . Las observaciones efectuadas indican que la mayor densidad anofelina se alcanza de Marzo a Abril y que el incremento del índice esporozoítico corresponde al descenso de la temperatura y el aumento de la humedad atmosférica que se registran durante los meses de otoño. El número reducido de A. punctimacula capturados en el interior de las habitaciones humanas y el no haber encontrado sus criaderos, nos obliga a suponer que las colecciones de agua que sirven de Criaderos al A. pseudopunctipennis, no reunen las condiciones que la especie anterior exigiría; por consiguiente, es probable que no desempeñe rol notable en la trasmisión de la malaria en los lugares donde hemos capturado a esta especie.

  7. La editorial Ricordi y su aportación a la publicidad italiana de principios del siglo XX / The publisher Ricordi and his contribution to the Italian advertising early twentieth century

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    Rut Francia Ferrero

    2013-09-01

    Full Text Available El objeto de estudio de la presente investigación es el nacimiento de las campañas publicitarias gráficas orquestadas por la fructífera colaboración entre empresarios, editores e ilustradores entre los siglos XIX y XX en Italia. El estudio se centra en la Casa Editorial Ricordi porque fue la creadora e impulsora del moderno cartel artístico y publicitario italiano, con un vasta producción de ejemplares, hoy considerados obras maestras del género. La etapa de oro del cartel italiano coincide, no por casualidad, con el predominio técnico y artístico de esta empresa en Italia que nada tenía que envidiar a sus competidoras francesas (como la prestigiosa Imprimerie Chaix parisina, tan querida por Jules Chéret, alemanas o inglesas. El período analizado (1890-1914 es el de mayor actividad y esplendor artístico en las artes gráficas. Son los años de los primeros pasos en el campo de la publicidad. Como en todos los comienzos, abundan las ideas, la energía, la ingenuidad y las ganas de experimentar. Es un tiempo lleno de cambios: la transformación económica, social e industrial que vivió Europa en un lapso tan corto de  tiempo es probablemente la mayor de su historia.The purpose of this research is the birth of graphic advertising campaigns orchestrated by the fruitful collaboration between employers, publishers and illustrators between the nineteenth and twentieth centuries in Italy. The study focuses on the Ricordi publishing house because it was the creator and driving force of the modern Italian poster art and advertising with a vast production of copies, today considered masterpieces of the genre. The golden age of Italian poster coincides, not coincidentally, with the technical and artistic dominance of this company in Italy that had nothing to envy their French competitors (including the prestigious Paris Imprimerie Chaix, so beloved by Jules Cheret, German or England. The period analyzed (1890-1914 is the most active and

  8. «Sangres» para propiciar la vida: metáforas y creencias sobre la concepción «humana» en el altiplano andino

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    Vicente Martín, Patricia

    2016-06-01

    Full Text Available This article reflects on the participation of telluric entities in regulating and propitiating fertility in general and «human» fertility in particular in the Andes region. The first part of this study deals with the participation of telluric forces in the breeding of livestock and the propitiation of plant life, as well as resources in general. In view of the visibility of these propitiatory rites, the genesis of new individuals is couched in a language in which references to «blood» and excessive heat abound. This study of the notions relating to conception and human fertility in the Andes involves the systematization of references found in ethnographic literature, and presentation of my own research in rural areas of southern Potosi (Bolivia. I then go on to consider the bodily rhetoric of life-promoting pregnant bodies and their specificities with a view to probing more deeply into the concept of fertility of the people of the Andean plateau.Este artículo tiene como objetivo la reflexión sobre la participación de las entidades tutelares en la regulación y propiciación de la fertilidad en general y de la «humana» en particular en los Andes. La primera parte del estudio aborda la participación de las fuerzas telúricas en la multiplicación del ganado y la propiciación de la vida vegetal, así como de las riquezas en general. Frente a la visibilidad de estos ritos propiciatorios, la génesis de los nuevos individuos se enmascara en un lenguaje en el cual abundan las referencias a las «sangres» y al exceso de calor. El estudio de las ideas acerca de la concepción y la fertilidad humana en los Andes pasa por una sistematización de las referencias halladas en la literatura etnográfica, y por la exposición de mis propias investigaciones en áreas rurales de Potosí. Tras ello se abordan las retóricas corporales de los cuerpos gestantes que propician la vida y sus especificidades con el fin de ahondar en la compresión de los

  9. De los literatos descontentos a los escritores-cineastas y los relatos fílmico-literarios

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    Sánchez Noriega, José Luis

    2010-02-01

    Full Text Available Studies and investigations about Literature and Film in Spanish are going through a Golden Age. Throughout the whole century, there have been a lot of misunderstandings between writers and the professional cinema world, dissatisfied with the screen versions or their contracts as scriptwriters. In the second half of 20th Century a new movie writers generation arise for whom Film is source of inspiration for their literature; In some cases that work cannot be understood without the background of the film universe. Beyond these writers, are the writers-filmmakers, which means, creators who express themselves with the same simplicity and aesthetics entity in literary texts and films. The contraposition or rivalry between literature and film does not make sense in case of works in which there takes place a dialogue between different levels of discourse and in the opposition of realistic and fictitious worlds.

    Los estudios e investigaciones en español sobre las relaciones entre la literatura y el cine están conociendo una edad de oro. A lo largo de todo un siglo, abundan los desencuentros entre los escritores y el mundo profesional del cine, insatisfechos con las adaptaciones o sus contratos como guionistas. En la segunda mitad del siglo XX surge una nueva generación de escritores cinéfilos para quienes el cine es fuente de inspiración y de temas para su literatura; en algunos casos esa obra no se comprende ni se concibe sin el trasfondo del universo del cine. Más allá de estos literatos están los escritores-cineastas, esto es, creadores que se expresan con la misma facilidad y entidad estética en obras escritas y en películas. La contraposición o rivalidad entre la literatura y el cine deja de tener sentido en el caso de obras en las que se produce un encuentro en el diálogo entre distintos niveles de discurso y en la oposición de mundos realistas y de ficción.

  10. Ocorrência e aspectos ecológicos de metazoários parasitos de peixes do Lago do Parque do Ingá, Maringá, Estado do Paraná - DOI: 10.4025/actascibiolsci.v29i3.507 Occurrence and ecological aspects of the metazoan fish parasites from Ingá lake, Maringá, Paraná State - DOI: 10.4025/actascibiolsci.v29i3.507

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    Marion Haruko Machado

    2007-12-01

    Full Text Available Nenhum estudo de peixes e parasitos foi realizado, até o momento, no Lago do Parque do Ingá que sofre influências antrópicas desde seu represamento, em 1970. Este trabalho analisou alguns aspectos ecológicos dos parasitos metazoários dos peixes deste lago. Dos peixes analisados, (69,5% estavam parasitados por pelo menos uma espécie de parasito. Foram encontrados 1.372 parasitos pertencentes à Nematoda (larvas e Platyhelminthes (Monogenea e Cestoda, sendo estes os mais prevalentes e numerosos. O encontro de larvas de cestóides em Tilapia rendalli e Oreochromis niloticus confirma a importância destas espécies como participantes de níveis tróficos intermediários. A maior abundância de T. rendalli e O. niloticus, no local, pode ser um fator determinante no recrutamento de parasitos. O parasito aproveita-se das espécies de hospedeiros mais abundantes para garantir o desenvolvimento de seu ciclo de vida e também por serem os mais disponíveis à predação pelas aves piscívoras ali presentes, o que torna o local de grande importância para a sustentação do ciclo de vida desses parasitos. A baixa diversidade de endoparasitos coletados pode ser justificada pela presença de metais pesados – Cu e Pb – no sedimento, o que deve estar interferindo no desenvolvimento dos invertebrados, possíveis hospedeiros intermediários.Ingá lake was dammed in 1970 and, since then, no study on fish and parasites had been done, but it has suffered anthropic influences. This study analyzed some ecological aspects of the metazoan parasites form this lake. From analyzed fish, 69.5% had at least one species of parasite. Among them, 1.372 parasites were found, prevailing Nematoda (larvae and Platyhelminthes (Monogenea and Cestoda. The discovery of cestode larvae in Tilapia rendalli and Oreochromis nitolicus confirms the importance of these species as participants of intermediate trophic levels. The great number of Tilapia rendalli and Oreochromis

  11. Ocorrência e aspectos ecológicos de metazoários parasitos de peixes do Lago do Parque do Ingá, Maringá, Estado do Paraná = Occurrence and ecological aspects of the metazoan fish parasites from Ingá lake, Maringá, Paraná State

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    Marion Haruko Machado

    2007-07-01

    Full Text Available Nenhum estudo de peixes e parasitos foi realizado, até o momento, no Lago do Parque do Ingá que sofre influências antrópicas desde seu represamento, em 1970. Este trabalho analisou alguns aspectos ecológicos dos parasitos metazoários dos peixes deste lago. Dos peixes analisados, (69,5% estavam parasitados por pelo menos uma espécie de parasito. Foram encontrados 1.372 parasitos pertencentes à Nematoda (larvas e Platyhelminthes (Monogenea e Cestoda, sendo estes os mais prevalentes e numerosos. O encontro de larvas decestóides em Tilapia rendalli e Oreochromis niloticus confirma a importância destas espécies como participantes de níveis tróficos intermediários. A maior abundância de T. rendalli e O. niloticus,no local, pode ser um fator determinante no recrutamento de parasitos. O parasito aproveita-se das espécies de hospedeiros mais abundantes para garantir o desenvolvimento de seu ciclo de vida e também por serem os mais disponíveis à predação pelas aves piscívorasali presentes, o que torna o local de grande importância para a sustentação do ciclo de vida desses parasitos. A baixa diversidade de endoparasitos coletados pode ser justificada pela presença de metais pesados – Cu e Pb – no sedimento, o que deve estar interferindo nodesenvolvimento dos invertebrados, possíveis hospedeiros intermediários.Ingá lake was dammed in 1970 and, since then, no study on fish and parasites had been done, but it has suffered anthropic influences. This study analyzed some ecological aspects of the metazoan parasites form this lake. From analyzed fish, 69.5% had at least one species of parasite. Among them, 1.372 parasites were found, prevailing Nematoda (larvae and Platyhelminthes (Monogenea and Cestoda. The discovery of cestode larvae in Tilapia rendalli and Oreochromis nitolicus confirms the importance of these species as participants of intermediate trophic levels. The great number of Tilapia rendalli and Oreochromis nitolicus

  12. Homology-based annotation of non-coding RNAs in the genomes of Schistosoma mansoni and Schistosoma japonicum

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    Santana Clara

    2009-10-01

    Full Text Available Abstract Background Schistosomes are trematode parasites of the phylum Platyhelminthes. They are considered the most important of the human helminth parasites in terms of morbidity and mortality. Draft genome sequences are now available for Schistosoma mansoni and Schistosoma japonicum. Non-coding RNA (ncRNA plays a crucial role in gene expression regulation, cellular function and defense, homeostasis, and pathogenesis. The genome-wide annotation of ncRNAs is a non-trivial task unless well-annotated genomes of closely related species are already available. Results A homology search for structured ncRNA in the genome of S. mansoni resulted in 23 types of ncRNAs with conserved primary and secondary structure. Among these, we identified rRNA, snRNA, SL RNA, SRP, tRNAs and RNase P, and also possibly MRP and 7SK RNAs. In addition, we confirmed five miRNAs that have recently been reported in S. japonicum and found two additional homologs of known miRNAs. The tRNA complement of S. mansoni is comparable to that of the free-living planarian Schmidtea mediterranea, although for some amino acids differences of more than a factor of two are observed: Leu, Ser, and His are overrepresented, while Cys, Meth, and Ile are underrepresented in S. mansoni. On the other hand, the number of tRNAs in the genome of S. japonicum is reduced by more than a factor of four. Both schistosomes have a complete set of minor spliceosomal snRNAs. Several ncRNAs that are expected to exist in the S. mansoni genome were not found, among them the telomerase RNA, vault RNAs, and Y RNAs. Conclusion The ncRNA sequences and structures presented here represent the most complete dataset of ncRNA from any lophotrochozoan reported so far. This data set provides an important reference for further analysis of the genomes of schistosomes and indeed eukaryotic genomes at large.

  13. Recent evidence for evolution of the genetic code

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    Osawa, S.; Jukes, T. H.; Watanabe, K.; Muto, A.

    1992-01-01

    The genetic code, formerly thought to be frozen, is now known to be in a state of evolution. This was first shown in 1979 by Barrell et al. (G. Barrell, A. T. Bankier, and J. Drouin, Nature [London] 282:189-194, 1979), who found that the universal codons AUA (isoleucine) and UGA (stop) coded for methionine and tryptophan, respectively, in human mitochondria. Subsequent studies have shown that UGA codes for tryptophan in Mycoplasma spp. and in all nonplant mitochondria that have been examined. Universal stop codons UAA and UAG code for glutamine in ciliated protozoa (except Euplotes octacarinatus) and in a green alga, Acetabularia. E. octacarinatus uses UAA for stop and UGA for cysteine. Candida species, which are yeasts, use CUG (leucine) for serine. Other departures from the universal code, all in nonplant mitochondria, are CUN (leucine) for threonine (in yeasts), AAA (lysine) for asparagine (in platyhelminths and echinoderms), UAA (stop) for tyrosine (in planaria), and AGR (arginine) for serine (in several animal orders) and for stop (in vertebrates). We propose that the changes are typically preceded by loss of a codon from all coding sequences in an organism or organelle, often as a result of directional mutation pressure, accompanied by loss of the tRNA that translates the codon. The codon reappears later by conversion of another codon and emergence of a tRNA that translates the reappeared codon with a different assignment. Changes in release factors also contribute to these revised assignments. We also discuss the use of UGA (stop) as a selenocysteine codon and the early history of the code.

  14. PwRn1, a novel Ty3/gypsy-like retrotransposon of Paragonimus westermani: molecular characters and its differentially preserved mobile potential according to host chromosomal polyploidy

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    Kong Yoon

    2008-10-01

    Full Text Available Abstract Background Retrotransposons have been known to involve in the remodeling and evolution of host genome. These reverse transcribing elements, which show a complex evolutionary pathway with diverse intermediate forms, have been comprehensively analyzed from a wide range of host genomes, while the information remains limited to only a few species in the phylum Platyhelminthes. Results A LTR retrotransposon and its homologs with a strong phylogenetic affinity toward CsRn1 of Clonorchis sinensis were isolated from a trematode parasite Paragonimus westermani via a degenerate PCR method and from an insect species Anopheles gambiae by in silico analysis of the whole mosquito genome, respectively. These elements, designated PwRn1 and AgCR-1 – AgCR-14 conserved unique features including a t-RNATrp primer binding site and the unusual CHCC signature of Gag proteins. Their flanking LTRs displayed >97% nucleotide identities and thus, these elements were likely to have expanded recently in the trematode and insect genomes. They evolved heterogeneous expression strategies: a single fused ORF, two separate ORFs with an identical reading frame and two ORFs overlapped by -1 frameshifting. Phylogenetic analyses suggested that the elements with the separate ORFs had evolved from an ancestral form(s with the overlapped ORFs. The mobile potential of PwRn1 was likely to be maintained differentially in association with the karyotype of host genomes, as was examined by the presence/absence of intergenomic polymorphism and mRNA transcripts. Conclusion Our results on the structural diversity of CsRn1-like elements can provide a molecular tool to dissect a more detailed evolutionary episode of LTR retrotransposons. The PwRn1-associated genomic polymorphism, which is substantial in diploids, will also be informative in addressing genomic diversification following inter-/intra-specific hybridization in P. westermani populations.

  15. Dollfustrema durum n. sp. and Heterobucephalopsis perardua n. sp. (Digenea: Bucephalidae) from the giant moray eel, Gymnothorax javanicus (Bleeker) (Anguilliformes: Muraenidae), and proposal of the Heterobucephalopsinae n. subfam.

    Science.gov (United States)

    Nolan, Matthew J; Curran, Stephen S; Miller, Terrence L; Cutmore, Scott C; Cantacessi, Cinzia; Cribb, Thomas H

    2015-12-01

    Two new species of bucephalid trematode (Platyhelminthes: Digenea) are described from the giant moray eel, Gymnothorax javanicus (Anguilliformes: Muraenidae), from off Lizard Island, Australia. We used a combined morphological and molecular-based approach targeting the internal transcribed spacer 2 (ITS2) of the ribosomal DNA (rDNA) and the D1-D3 region of the large subunit (28S) of rDNA to circumscribe the species. Dollfustrema durum n. sp. is distinguished from seven congeners in having 5-6 rows of enlarged body spines circling the anterior portion of the rhynchus. From the remaining 10 species, D. durum n. sp. differs in body length, and in having a caecum that terminates posteriorly to the confluent arc formed by the vitelline follicles, gonads predominantly anterior to the pharynx, testes in tandem, an anterior testis positioned posteriorly to the vitelline follicles, and the pre-vitelline field 23-40% of the body length. Heterobucephalopsis perardua n. sp. differs from Heterobucephalopsis gymnothoracis, the type- and only other reported species, in being two to three times smaller. Heterobucephalopsis, currently considered a genus inquirendum, is confirmed as valid and is rediagnosed. Bayesian inference analysis of 28S rDNA sequences representing 28 species from nine genera and four subfamilies of bucephalid, indicates that i) subfamily classifications previously based on morphological characters are broadly robust, ii) the sequence representing H. perardua n. sp. is resolved as distinct, and basal, to sequences representing the Bucephalinae, the Prosorhynchinae, the Paurorhynchinae, and the Dolichoenterinae, iii) the Dolichoenterinae and the Prosorhynchinae are monophyletic sister clades, basal to the Bucephalinae and the Paurorhynchinae, iv) sequences representing Grammatorcynicola, Prosorhynchus, and Dollfustrema are also monophyletic, v) the Bucephalinae is paraphyletic relative to the Paurorhynchinae, and vi) the bucephaline genera Prosorhynchoides

  16. High-intensity cardiac infections of Phthinomita heinigerae n. sp. (Digenea: Aporocotylidae) in the orangelined cardinalfish, Taeniamia fucata (Cantor), off Heron Island on the Great Barrier Reef.

    Science.gov (United States)

    Nolan, Matthew J; Cantacessi, Cinzia; Cutmore, Scott C; Cribb, Thomas H; Miller, Terrence L

    2016-10-01

    We report a new species of aporocotylid trematode (Platyhelminthes: Digenea) from the heart of the orangelined cardinalfish, Taeniamia fucata (Cantor), from off Heron Island on the southern Great Barrier Reef. We used an integrated approach, analysing host distribution, morphology, and genetic data from the internal transcribed spacer 2 of the ribosomal DNA, to circumscribe Phthinomita heinigerae n. sp. This is the first species of Phthinomita Nolan & Cribb, 2006 reported from the Apogonidae; existing species and known 'types' are recorded from species of the Labridae, Mullidae, and Siganidae. The new species is distinguished from its 11 congeners in having a body 2977-3539 long and 16.5-22.4 times longer than wide, an anterior testis 6.2-8.2 times longer than wide and 8.3-13.0 times longer than the posterior testis, a posterior testis whose width is 35-56% of the body width, and an ovary positioned 11-13% of the body length from the posterior end, and is entirely anterior to the posterior margin of the anterior testis. In addition, 2-34 base differences (0.4-7.0% sequence divergence over 485 base positions) were detected among the ITS2 sequence representing P. heinigerae n. sp. and the 14 representing other Phthinomita species/molecular types. Prevalence and intensity of infection with P. heinigerae n. sp. was relatively high within the heart tissue of T. fucata, with 19 of 20 fish examined from off Heron Island infected (95%) with 7-25 adult worms (arithmetic mean 16.6). Infections by these parasites accounted for an occupation of 7-30% of the total estimated heart volume.

  17. Phylogenetic analyses and characterization of RNase X25 from Drosophila melanogaster suggest a conserved housekeeping role and additional functions for RNase T2 enzymes in protostomes.

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    Linda Ambrosio

    Full Text Available Ribonucleases belonging to the RNase T2 family are enzymes associated with the secretory pathway that are almost absolutely conserved in all eukaryotes. Studies in plants and vertebrates suggest they have an important housekeeping function in rRNA recycling. However, little is known about this family of enzymes in protostomes. We characterized RNase X25, the only RNase T2 enzyme in Drosophila melanogaster. We found that RNase X25 is the major contributor of ribonuclease activity in flies as detected by in gel assays, and has an acidic pH preference. Gene expression analyses showed that the RNase X25 transcript is present in all adult tissues and developmental stages. RNase X25 expression is elevated in response to nutritional stresses; consistent with the hypothesis that this enzyme has a housekeeping role in recycling RNA. A correlation between induction of RNase X25 expression and autophagy was observed. Moreover, induction of gene expression was triggered by oxidative stress suggesting that RNase X25 may have additional roles in stress responses. Phylogenetic analyses of this family in protostomes showed that RNase T2 genes have undergone duplication events followed by divergence in several phyla, including the loss of catalytic residues, and suggest that RNase T2 proteins have acquired novel functions. Among those, it is likely that a role in host immunosuppression evolved independently in several groups, including parasitic Platyhelminthes and parasitoid wasps. The presence of only one RNase T2 gene in the D. melanogaster genome, without any other evident secretory RNase activity detected, makes this organism an ideal system to study the cellular functions of RNase T2 proteins associated with RNA recycling and maintenance of cellular homeostasis. On the other hand, the discovery of gene duplications in several protostome genomes also presents interesting new avenues to study additional biological functions of this ancient family of proteins.

  18. Characterization of microRNAs from Orientobilharzia turkestanicum, a neglected blood fluke of human and animal health significance.

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    Chun-Ren Wang

    Full Text Available The neglected blood flukes Orientobilharzia spp. belonging to the Platyhelminthes, infect animals in a number of countries of the world, and cause cercarial dermatitis in humans, as well as significant diseases and even death in economically-important animals. MicroRNAs (miRNAs are now considered to be a key mechanism of gene regulation. Herein, we investigated the global miRNA expression profile of adult O. turkestanicum using next-generation sequencing technology and real-time quantitative PCR, to gain further information on the role of these molecules in host invasion and the parasitic lifestyle of this species. A total of 13.48 million high quality reads were obtained out of 13.78 million raw sequencing reads, with 828 expressed miRNAs identified. Phylogenetic analysis showed that the miRNAs of O. turkestanicum were still rapidly evolving and there was a "directed mutation" pattern compared with that of other species. Target mRNAs were successfully predicted to 518 miRNAs. These targets included energy metabolism, transcription initiation factors, signal transduction, growth factor receptors. miRNAs targeting egg proteins, including major egg antigen p40, and heat shock proteins were also found. Enrichment analysis indicated enrichment for mRNAs involved in catalytic, binding, transcription regulators and translation regulators. The present study represented the first large-scale characterization of O. turkestanicum miRNAs, which provides novel resources for better understanding the complex biology of this zoonotic parasite, which, in turn, has implications for the effective control of the disease it causes.

  19. Characterization of microRNAs from Orientobilharzia turkestanicum, a neglected blood fluke of human and animal health significance.

    Science.gov (United States)

    Wang, Chun-Ren; Xu, Min-Jun; Fu, Jing-Hua; Nisbet, Alasdair J; Chang, Qiao-Cheng; Zhou, Dong-Hui; Huang, Si-Yang; Zou, Feng-Cai; Zhu, Xing-Quan

    2012-01-01

    The neglected blood flukes Orientobilharzia spp. belonging to the Platyhelminthes, infect animals in a number of countries of the world, and cause cercarial dermatitis in humans, as well as significant diseases and even death in economically-important animals. MicroRNAs (miRNAs) are now considered to be a key mechanism of gene regulation. Herein, we investigated the global miRNA expression profile of adult O. turkestanicum using next-generation sequencing technology and real-time quantitative PCR, to gain further information on the role of these molecules in host invasion and the parasitic lifestyle of this species. A total of 13.48 million high quality reads were obtained out of 13.78 million raw sequencing reads, with 828 expressed miRNAs identified. Phylogenetic analysis showed that the miRNAs of O. turkestanicum were still rapidly evolving and there was a "directed mutation" pattern compared with that of other species. Target mRNAs were successfully predicted to 518 miRNAs. These targets included energy metabolism, transcription initiation factors, signal transduction, growth factor receptors. miRNAs targeting egg proteins, including major egg antigen p40, and heat shock proteins were also found. Enrichment analysis indicated enrichment for mRNAs involved in catalytic, binding, transcription regulators and translation regulators. The present study represented the first large-scale characterization of O. turkestanicum miRNAs, which provides novel resources for better understanding the complex biology of this zoonotic parasite, which, in turn, has implications for the effective control of the disease it causes.

  20. Identification of Echinococcus granulosus microRNAs and their expression in different life cycle stages and parasite genotypes.

    Science.gov (United States)

    Cucher, M; Prada, L; Mourglia-Ettlin, G; Dematteis, S; Camicia, F; Asurmendi, S; Rosenzvit, M

    2011-03-01

    The aetiological agent of cystic hydatid disease, the platyhelminth parasite Echinococcus granulosus, undergoes a series of metamorphic events during its complex life cycle. One of its developmental stages, the protoscolex, shows a remarkable degree of heterogeneous morphogenesis, being able to develop either into the vesicular or strobilar direction. Another level of complexity is added by the existence of genotypes or strains that differ in the range of intermediate hosts where they can develop and form fertile cysts. These features make E. granulosus an interesting model for developmental studies. Hence, we focused on the study of the regulation of gene expression by microRNAs (miRNAs), one of the key mechanisms that control development in metazoans and plants and which has not been analysed in E. granulosus yet. In this study, we cloned 38 distinct miRNAs, including four candidate new miRNAs that seem to be specific to Echinococcus spp. Thirty-four cloned sequences were orthologous to miRNAs already described in other organisms and were grouped in 16 metazoan miRNA families, some of them known for their role in the development of other organisms. The expression of some of the cloned miRNAs differs according to the parasite life cycle stage analysed, showing differential developmental expression. We did not detect differences in the expression of the analysed miRNAs between protoscoleces of two parasite genotypes. This work sets the scene for the study of gene regulation mediated by miRNAs in E. granulosus and provides a new approach to study the molecules involved in its developmental plasticity and intermediate host specificity. Understanding the developmental processes of E. granulosus may help to find new strategies for the control of cystic hydatid disease, caused by the metacestode stage of the parasite.

  1. Cestodes from deep-water squaliform sharks in the Azores

    Science.gov (United States)

    Caira, Janine N.; Pickering, Maria

    2013-12-01

    The majority of our knowledge on marine tapeworms (cestodes) is limited to taxa that are relatively easy to obtain (i.e., those that parasitize shallower-water species). The invitation to participate in a deep-water research survey off the Condor seamount in the Azores offered the opportunity to gain information regarding parasites of the less often studied sharks of the mesopelagic and bathypelagic zone. All tapeworms (Platyhelminthes: Cestoda) found parasitizing the spiral intestine of squaliform shark species (Elasmobranchii: Squaliformes) encountered as part of this survey, as well as some additional Azorean sampling from previous years obtained from local fishermen are reported. In total, 112 shark specimens of 12 species of squaliform sharks representing 4 different families from depths ranging between 400 and 1290 m were examined. Cestodes were found in the spiral intestines from 11 of the 12 squaliform species examined: Deania calcea, D. cf. profundorum, D. profundorum, Etmopterus princeps, E. pusillus, E. spinax, Centroscyllium fabricii, Centroscymnus coelolepis, C. cryptacanthus, C. crepidater, and Dalatias licha. No cestodes were found in the spiral intestines of Centrophorus squamosus. Light microscopy and scanning electron microscopy revealed several potentially novel trypanorhynch and biloculated tetraphyllidean species. Aporhynchid and gilquiniid trypanorhynchs dominated the adult cestode fauna of Etmopterus and Deania host species, respectively, while larval phyllobothriids were found across several host genera, including, Deania, Centroscyllium, and Centroscymnus. These results corroborate previous findings that deep-water cestode faunas are relatively depauperate and consist primarily of trypanorhynchs of the families Gilquiniidae and Aporhynchidae and larval tetraphyllideans. A subset of specimens of most cestode species was preserved in ethanol for future molecular analysis to allow more definitive determinations of the identification of the

  2. Morphology, molecules, and monogenean parasites: an example of an integrative approach to cichlid biodiversity.

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    Maarten Van Steenberge

    Full Text Available The unparalleled biodiversity of Lake Tanganyika (Africa has fascinated biologists for over a century; its unique cichlid communities are a preferred model for evolutionary research. Although species delineation is, in most cases, relatively straightforward, higher-order classifications were shown not to agree with monophyletic groups. Here, traditional morphological methods meet their limitations. A typical example are the tropheine cichlids currently belonging to Simochromis and Pseudosimochromis. The affiliations of these widespread and abundant cichlids are poorly understood. Molecular work suggested that genus and species boundaries should be revised. Moreover, previous morphological results indicated that intraspecific variation should be considered to delineate species in Lake Tanganyika cichlids. We review the genera Simochromis and Pseudosimochromis using an integrative approach. Besides a morphometric study and a barcoding approach, monogenean Cichlidogyrus (Platyhelminthes: Ancyrocephalidae gill parasites, often highly species-specific, are used as complementary markers. Six new species are described. Cichlidogyrus raeymaekersi sp. nov., C. muterezii sp. nov. and C. banyankimbonai sp. nov. infect S. diagramma. Cichlidogyrus georgesmertensi sp. nov. was found on S. babaulti and S. pleurospilus, C. franswittei sp. nov. on both S. marginatus and P. curvifrons and C. frankwillemsi sp. nov. only on P. curvifrons. As relatedness between Cichlidogyrus species usually reflects relatedness between hosts, we considered Simochromis monotypic because the three Cichlidogyrus species found on S. diagramma belonged to a different morphotype than those found on the other Simochromis. The transfer of S. babaulti, S. marginatus, S. pleurospilus and S. margaretae to Pseudosimochromis was justified by the similarity of their Cichlidogyrus fauna and the intermediate morphology of S. margaretae. Finally parasite data also supported the synonymy between S

  3. Global expression analysis revealed novel gender-specific gene expression features in the blood fluke parasite Schistosoma japonicum.

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    Xianyu Piao

    Full Text Available BACKGROUND: Schistosoma japonicum is one of the remarkable Platyhelminths that are endemic in China and Southeast Asian countries. The parasite is dioecious and can reside inside the host for many years. Rapid reproduction by producing large number of eggs and count-react host anti-parasite responses are the strategies that benefit long term survival of the parasite. Praziquantel is currently the only drug that is effective against the worms. Development of novel antiparasite reagents and immune-prevention measures rely on the deciphering of parasite biology. The decoding of the genomic sequence of the parasite has made it possible to dissect the functions of genes that govern the development of the parasite. In this study, the polyadenylated transcripts from male and female S. japonicum were isolated for deep sequencing and the sequences were systematically analysed. RESULTS: First, the number of genes actively expressed in the two sexes of S. japonicum was similar, but around 50% of genes were biased to either male or female in expression. Secondly, it was, at the first time, found that more than 50% of the coding region of the genome was transcribed from both strands. Among them, 65% of the genes had sense and their cognate antisense transcripts co-expressed, whereas 35% had inverse relationship between sense and antisense transcript abundance. Further, based on gene ontological analysis, more than 2,000 genes were functionally categorized and biological pathways that are differentially functional in male or female parasites were elucidated. CONCLUSIONS: Male and female schistosomal parasites differ in gene expression patterns, many metabolic and biological pathways have been identified in this study and genes differentially expressed in gender specific manner were presented. Importantly, more than 50% of the coding regions of the S. japonicum genome transcribed from both strands, antisense RNA-mediated gene regulation might play a critical

  4. Cysteine and Aspartyl Proteases Contribute to Protein Digestion in the Gut of Freshwater Planaria

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    Goupil, Louise S.; Ivry, Sam L.; Hsieh, Ivy; Suzuki, Brian M.; Craik, Charles S.; O’Donoghue, Anthony J.; McKerrow, James H.

    2016-01-01

    Proteases perform numerous vital functions in flatworms, many of which are likely to be conserved throughout the phylum Platyhelminthes. Within this phylum are several parasitic worms that are often poorly characterized due to their complex life-cycles and lack of responsiveness to genetic manipulation. The flatworm Schmidtea mediterranea, or planaria, is an ideal model organism to study the complex role of protein digestion due to its simple life cycle and amenability to techniques like RNA interference (RNAi). In this study, we were interested in deconvoluting the digestive protease system that exists in the planarian gut. To do this, we developed an alcohol-induced regurgitation technique to enrich for the gut enzymes in S. mediterranea. Using a panel of fluorescent substrates, we show that this treatment produces a sharp increase in proteolytic activity. These enzymes have broad yet diverse substrate specificity profiles. Proteomic analysis of the gut contents revealed the presence of cysteine and metallo-proteases. However, treatment with class-specific inhibitors showed that aspartyl and cysteine proteases are responsible for the majority of protein digestion. Specific RNAi knockdown of the cathepsin B-like cysteine protease (SmedCB) reduced protein degradation in vivo. Immunohistochemistry and whole-mount in situ hybridization (WISH) confirmed that the full-length and active forms of SmedCB are found in secretory cells surrounding the planaria intestinal lumen. Finally, we show that the knockdown of SmedCB reduces the speed of tissue regeneration. Defining the roles of proteases in planaria can provide insight to functions of conserved proteases in parasitic flatworms, potentially uncovering drug targets in parasites. PMID:27501047

  5. Schistosome asparaginyl endopeptidase (legumain) is not essential for cathepsin B1 activation in vivo.

    Science.gov (United States)

    Krautz-Peterson, Greice; Skelly, Patrick J

    2008-05-01

    Schistosomes are parasitic platyhelminths that constitute an important public health problem. Adult parasites live in the vasculature of their vertebrate hosts where they consume blood. Ingested blood proteins are degraded by a proteolytic cascade. One of the best characterized schistosome proteases is cathepsin B1 (SmCB1 or Sm31). This protein is synthesized as a large 38 kDa precursor form which is proteolytically cleaved to yield a mature, active 31 kDa enzyme. A second schistosome protease--the asparaginyl endopeptidase SmAE (also known as Sm32, or schistosome legumain), has been proposed to proteolytically convert the 38 kDa precursor SmCB1 into its mature form. Recombinant activated SmAE has been shown to trans-process SmCB1 into the mature, catalytic form in vitro. In the present study, our aim was to test the hypothesis that in vivo SmAE likewise processes SmCB1 into its active form. To do this, expression of the SmAE gene was suppressed in adult Schistosoma mansoni using RNA interference (RNAi). The results of these experiments show that, even in the absence of detectable SmAE protein, SmCB1 is fully processed and active and support the assertion that SmAE is not essential to activate SmCB1 in vivo. The data indicate that our original hypothesis is incorrect and that SmAE is not pivotal in the in vivo conversion of cathepsin B1 into its mature, active form.

  6. Molecular cloning and characterization of growth factor receptor bound-protein in Clonorchis sinensis.

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    Xuelian Bai

    Full Text Available BACKGROUND: Clonorchis sinensis causes clonorchiasis, a potentially serious disease. Growth factor receptor-bound protein 2 (Grb2 is a cytosolic protein conserved among animals and plays roles in cellular functions such as meiosis, organogenesis and energy metabolism. In the present study, we report first molecular characters of growth factor receptor bound-protein (CsGrb2 from C. sinensis as counter part of Grb2 from animals and its possible functions in development and organogenesis of C. sinensis. METHODOLOGY/PRINCIPAL FINDINGS: A CsGrb2 cDNA clone retrieved from the C. sinensis transcriptome encoded a polypeptide with a SH3-SH2-SH3 structure. Recombinant CsGrb2 was bacterially produced and purified to homogeneity. Native CsGrb2 with estimated molecular weight was identified from C. sinensis adult extract by western blotting using a mouse immune serum to recombinant CsGrb2. CsGrb2 transcripts was more abundant in the metacercariae than in the adults. Immunohistochemical staining showed that CsGrb2 was localized to the suckers, mesenchymal tissues, sperms in seminal receptacle and ovary in the adults, and abundantly expressed in most organs of the metacercariae. Recombinant CsGrb2 was evaluated to be little useful as a serodiagnostic reagent for C. sinesis human infections. CONCLUSION: Grb2 protein found in C. sinensis was conserved among animals and suggested to play a role in the organogenesis, energy metabolism and mitotic spermatogenesis of C. sinensis. These findings from C. sinensis provide wider understanding on diverse function of Grb2 in lower animals such as platyhelminths.

  7. Integrative taxonomy of European parasitic flatworms of the genus Metorchis Looss, 1899 (Trematoda: Opisthorchiidae).

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    Sitko, Jiljí; Bizos, Jiří; Sherrard-Smith, Eleanor; Stanton, David W G; Komorová, Petronela; Heneberg, Petr

    2016-06-01

    Metorchis spp. are flukes (Platyhelminthes: Digenea) that infect vertebrates, including humans, dogs, cats, poultry and wild game, with cyprinid freshwater fish serving as typical second intermediate hosts. In their definitive hosts, the Metorchis spp. are difficult to identify to species. We provide and analyze sequences of two nuclear (18S rDNA and ITS2) and two mitochondrial (CO1 and ND1) DNA loci of four morphologically identified European species of the Metorchis, namely Metorchis albidus, Metorchis bilis, Metorchis crassiusculus and Metorchis xanthosomus, and of another opisthorchiid, Euamphimerus pancreaticus. DNA analysis suggests that the Metorchis specimens identified morphologically as M. albidus (from Lutra lutra), M. bilis (from Phalacrocorax carbo) and M. crassiusculus (from Aquila heliaca and Buteo rufinus) represent a single species. Thus, M. albidus (Braun, 1893) Loos, 1899 and M. crassiusculus (Rudolphi, 1809) Looss, 1899 are recognized as junior subjective synonyms of M. bilis (Braun, 1790) Odening, 1962. We also provide comparative measurements of the Central European Metorchis spp., and address their tissue specificity and prevalence based on the examination of extensive bird cohort from 1962 to 2015. M. bilis and M. xanthosomus can be morphologically diagnosed by measuring the extent of genitalia relative to body length and by the size ratio of their suckers. They also differ in their core definitive hosts, with ducks (Anas, Aythya) and coots (Fulica) hosting M. xanthosomus, and cormorants (Phalacrocorax), the birds of prey (Buteo, Aquila, etc.), piscivorous mammals (Lutra, Vulpes, Ursus, etc.) and humans hosting M. bilis. Previous reports on the Metorchis spp. contain numerous suspected misidentifications. PMID:26794684

  8. Cysteine and Aspartyl Proteases Contribute to Protein Digestion in the Gut of Freshwater Planaria.

    Science.gov (United States)

    Goupil, Louise S; Ivry, Sam L; Hsieh, Ivy; Suzuki, Brian M; Craik, Charles S; O'Donoghue, Anthony J; McKerrow, James H

    2016-08-01

    Proteases perform numerous vital functions in flatworms, many of which are likely to be conserved throughout the phylum Platyhelminthes. Within this phylum are several parasitic worms that are often poorly characterized due to their complex life-cycles and lack of responsiveness to genetic manipulation. The flatworm Schmidtea mediterranea, or planaria, is an ideal model organism to study the complex role of protein digestion due to its simple life cycle and amenability to techniques like RNA interference (RNAi). In this study, we were interested in deconvoluting the digestive protease system that exists in the planarian gut. To do this, we developed an alcohol-induced regurgitation technique to enrich for the gut enzymes in S. mediterranea. Using a panel of fluorescent substrates, we show that this treatment produces a sharp increase in proteolytic activity. These enzymes have broad yet diverse substrate specificity profiles. Proteomic analysis of the gut contents revealed the presence of cysteine and metallo-proteases. However, treatment with class-specific inhibitors showed that aspartyl and cysteine proteases are responsible for the majority of protein digestion. Specific RNAi knockdown of the cathepsin B-like cysteine protease (SmedCB) reduced protein degradation in vivo. Immunohistochemistry and whole-mount in situ hybridization (WISH) confirmed that the full-length and active forms of SmedCB are found in secretory cells surrounding the planaria intestinal lumen. Finally, we show that the knockdown of SmedCB reduces the speed of tissue regeneration. Defining the roles of proteases in planaria can provide insight to functions of conserved proteases in parasitic flatworms, potentially uncovering drug targets in parasites. PMID:27501047

  9. EST based phylogenomics of Syndermata questions monophyly of Eurotatoria

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    Bucher Gregor

    2008-12-01

    Full Text Available Abstract Background The metazoan taxon Syndermata comprising Rotifera (in the classical sense of Monogononta+Bdelloidea+Seisonidea and Acanthocephala has raised several hypotheses connected to the phylogeny of these animal groups and the included subtaxa. While the monophyletic origin of Syndermata and Acanthocephala is well established based on morphological and molecular data, the phylogenetic position of Syndermata within Spiralia, the monophyletic origin of Monogononta, Bdelloidea, and Seisonidea and the acanthocephalan sister group are still a matter of debate. The comparison of the alternative hypotheses suggests that testing the phylogenetic validity of Eurotatoria (Monogononta+Bdelloidea is the key to unravel the phylogenetic relations within Syndermata. The syndermatan phylogeny in turn is a prerequisite for reconstructing the evolution of the acanthocephalan endoparasitism. Results Here we present our results from a phylogenomic approach studying i the phylogenetic position of Syndermata within Spiralia, ii the monophyletic origin of monogononts and bdelloids and iii the phylogenetic relations of the latter two taxa to acanthocephalans. For this analysis we have generated EST libraries of Pomphorhynchus laevis, Echinorhynchus truttae (Acanthocephala and Brachionus plicatilis (Monogononta. By extending these data with database entries of B. plicatilis, Philodina roseola (Bdelloidea and 25 additional metazoan species, we conducted phylogenetic reconstructions based on 79 ribosomal proteins using maximum likelihood and bayesian approaches. Our findings suggest that the phylogenetic position of Syndermata within Spiralia is close to Platyhelminthes, that Eurotatoria are not monophyletic and that bdelloids are more closely related to acanthocephalans than monogononts. Conclusion Mapping morphological character evolution onto molecular phylogeny suggests the (partial or complete reduction of the corona and the emergence of a retractable

  10. Molecular cloning and characterization of taurocyamine kinase from Clonorchis sinensis: a candidate chemotherapeutic target.

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    Jing-Ying Xiao

    2013-11-01

    Full Text Available BACKGROUND: Adult Clonorchis sinensis lives in the bile duct and causes endemic clonorchiasis in East Asian countries. Phosphagen kinases (PK constitute a highly conserved family of enzymes, which play a role in ATP buffering in cells, and are potential targets for chemotherapeutic agents, since variants of PK are found only in invertebrate animals, including helminthic parasites. This work is conducted to characterize a PK from C. sinensis and to address further investigation for future drug development. METHODOLOGY/PRINCIPAL FINDINGS: [corrected] A cDNA clone encoding a putative polypeptide of 717 amino acids was retrieved from a C. sinensis transcriptome. This polypeptide was homologous to taurocyamine kinase (TK of the invertebrate animals and consisted of two contiguous domains. C. sinensis TK (CsTK gene was reported and found consist of 13 exons intercalated with 12 introns. This suggested an evolutionary pathway originating from an arginine kinase gene group, and distinguished annelid TK from the general CK phylogenetic group. CsTK was found not to have a homologous counterpart in sequences analysis of its mammalian hosts from public databases. Individual domains of CsTK, as well as the whole two-domain enzyme, showed enzymatic activity and specificity toward taurocyamine substrate. Of the CsTK residues, R58, I60 and Y84 of domain 1, and H60, I63 and Y87 of domain 2 were found to participate in binding taurocyamine. CsTK expression was distributed in locomotive and reproductive organs of adult C. sinensis. Developmentally, CsTK was stably expressed in both the adult and metacercariae stages. Recombinant CsTK protein was found to have low sensitivity and specificity toward C. sinensis and platyhelminth-infected human sera on ELISA. CONCLUSION: CsTK is a promising anti-C. sinensis drug target since the enzyme is found only in the C. sinensis and has a substrate specificity for taurocyamine, which is different from its mammalian counterpart

  11. The molecular symplesiomorphies shared by the stem groups of metazoan evolution: can sites as few as 1% have a significant impact on recognizing the phylogenetic position of myzostomida?

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    Wang, Yanhui; Xie, Qiang

    2014-08-01

    Although it is clear that taxon sampling, alignments, gene sampling, tree reconstruction methods and the total length of the sequences used are critical to the reconstruction of evolutionary history, weakly supported or misleading nodes exist in phylogenetic studies with no obvious flaw in those aspects. The phylogenetic studies focusing on the basal part of bilaterian evolution are such a case. During the past decade, Myzostomida has appeared in the basal part of Bilateria in several phylogenetic studies of Metazoa. However, most researchers have entertained only two competing hypotheses about the position of Myzostomida-an affinity with Annelida and an affinity with Platyhelminthes. In this study, dozens of symplesiomorphies were discovered by means of ancestral state reconstruction in the complete 18S and 28S rDNAs shared by the stem groups of Metazoa. By contrastive analysis on the datasets with or without such symplesiomorphic sites, we discovered that Myzostomida and other basal groups are basal lineages of Bilateria due to the corresponding symplesiomorphies shared with earlier lineages. As such, symplesiomorphies account for approximately 1-2% of the whole dataset have an essential impact on phylogenetic inference, and this study reminds molecular systematists of the importance of carrying out ancestral state reconstruction at each site in sequence-based phylogenetic studies. In addition, reasons should be explored for the low support of the hypothesis that Myzostomida belongs to Annelida in the results of phylogenomic studies. Future phylogenetic studies concerning Myzostomida should include all of the basal lineages of Bilateria to avoid directly neglecting the stand-alone basal position of Myzostomida as a potential hypothesis. PMID:25128981

  12. Geología del complejo volcánico Los Menucos en el área tipo: Río Negro Geology of the Volcanic Complex Los Menucos in the type locality, Río Negro

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    Hebe Lema

    2008-03-01

    Full Text Available Los afloramientos del Complejo volcánico Los Menucos - que cubren una superficie aproximada de 8.000 km² - representan la actividad magmática acontecida durante el Triásico (- Jurásico inferior? en el macizo Norpatagónico. Este complejo está integrado por diversos tipos de depósitos piroclásticos, lavas, diques y cuerpos epizonales a subvolcánicos, y presenta intercalaciones sedimentarias cuyas mejores exposiciones están al oeste de la localidad de Los Menucos. La composición de las rocas volcánicas varía desde leucoriolitas a basandesitas. Los cuerpos son de naturaleza diorítica a monzonítica, con una facies leucogranítica. En un pórfiro monzonítico cuarzoso se obtuvo una edad por isocrona Ar39-Ar40, de 206,9 ± 1,2 Ma. En algunos sectores el espesor mínimo de los depósitos puede estimarse en 2.000 metros, debido fundamentalmente al apilamiento de mantos ignimbríticos, entre los que abundan ignimbritas mesosilícicas con altos porcentajes de cristaloclastos. A partir de un mapeo detallado de litofacies se han reconocido dos áreas que se interpretan como centros de emisión volcánica; otras efusiones están vinculadas a fisuras. La estructura regional se caracteriza por fallas de dimensiones kilométricas, que estuvieron activas durante el magmatismo. Las más importantes tienen rumbo general este-oeste y desplazamientos de rumbo kilométricos, con predominio de una cinemática dextral. Varios rasgos geomórficos que interrumpen la peneplanicie regional están asociados al fallamiento.Los Menucos Volcanic Complex outcrops within an area of about 8,000 km² of the Northpatagonian Massif. It is the major magmatic event that occurred during the Triassic (- Early Jurassic? in the region. The volcanic complex is constituted by pyroclastic deposits, lava flows, dykes and epizonal to subvolcanic bodies, with interbedded sediments whose better exposures are located to the west of the Los Menucos locality. The composition of the

  13. Qué es la ética económica

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    Georges Enderle

    1993-06-01

    Full Text Available Al observar la renuencia de muchos practicantes de la actividad empresarial para emplear la palabra ética o tan siquiera para estar dispuestos a discutir sobre ética, en este ensayo se hace un esfuerzo por definir lo que debería ser la ética económica y empresarial. Se sugiere el énfasis sobre una “nueva práctica”, un enfoque que reconoce la prioridad de la practica sobre la teoría. El  centro de atención esta en el mejoramiento de la calidad ética al tomar decisiones y al emprender acciones. Debe distinguirse tres niveles: el nivel micro o del individuo, el meso o nivel de las firmas y organizaciones, y el nivel macro de las economías nacionales y transnacionales. También deben considerarse tres grupos de valores: personales, colectivos y generales. Siempre debe tenerse en mente las inter-relaciones entre estos niveles y valores. Se precisa de un modelo de cooperación entre la economía y la ética que pueda superar los problemas del idealismo o de reducir la ética a un aparato instrumental. Un enfoque basado en la toma de decisiones ofrece la mayor de las promesas. Al  mismo tiempo, debe enfrentarse el problema del pluralismo, problema que sólo podrá ser resuelto encontrando un consenso superpuesto. Lo simple de la pregunta -¿qué es la ética económica?- va de la mano con la dificultad de dar una respuesta clara y comprehensiva. Es sumamente confuso, colorido y variado lo que hoy se escucha en nombre de la “ética económica y empresarial”. Abundan las expectativas múltiples, e incluso contradictorias en este campo. Si bien soy muy consciente de estos problemas tratare, sin embargo, de dar algunas respuestas provisionales y, con suerte, aclaratorias a nuestra pregunta simple. Ellas tienen el color personal, influenciado por mi experiencia europeo-occidental, e inspiradas por mi esperanza de que los esfuerzos en el campo de la ética económica contribuyan a hacer frente a los grandes retos de nuestro tiempo de

  14. INCENDIARIOS "Es preferible morir por el fuego, en combate, que morir en casa, por el hambre: Fidel Castro" Arson

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    Lisieux Elaine de BorbaTelles

    2012-09-01

    Full Text Available Antecedentes. El concepto de fuego siempre ha atraído la atención del hombre. En la literatura abundan referencias a este término, que tanto puede representar poder y pasión como terror y destrucción. El incendio es un delito de fácil ejecución, pero de difícil investigación. La prevalencia de este delito es de 1,13%. La incidencia de este crimen está creciendo alrededor del mundo, provocando un impacto social importante por las pérdidas financieras, muertes, lesiones físicas y secuelas emocionales dejadas en sus víctimas. El comportamiento incendiario puede ser observado desde la infancia, siendo que cerca de la mitad de los individuos presos por incendios se encuentran en la adolescencia. El consumo de alcohol está asociado a la conducta incendiaria, en la mitad de individuos que cometieron tal delito motivados por venganza. Objetivo. Revisar los estudios más recientes sobre el perfil de los incendiarios, las características diagnósticas, los factores de riesgo, la neurobiología, el tratamiento, la reincidencia y el pronóstico. Material y métodos. Revisión de la literatura. En la revisión de la literatura se encuentran que los incendiarios son una categoría heterogénea de criminales. Se torna interesante el desarrollo de una clasificación para los mismos, considerando las características del agresor, la presencia de eventual enfermedad mental, los aspectos del crimen y las motivaciones. Conclusión. Hasta el presente, la población de incendiarios estudiada es subrepresentada, pues apenas un pequeño porcentaje es enviado para evaluación diagnóstica y tratamiento. Se expone, así, una incongruencia entre los grandes daños emocionales y financieros, causadas por este delito, y la atención que él recibe de la comunidad científica.Background. The concept of fire has always attracted human attention. There are abundant references to the term in worldwide literature, representing power and passion as well as terror

  15. The Haram al-Sharīf collection of Arabic legal documents in Jerusalem: a Mamlūk court archive?

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    Müller, Christian

    2011-12-01

    797/1395. De esta época abundan también documentos relativos a las transacciones financieras realizadas dentro de instituciones para las que el juez tenía jurisdicción. La necrología realizada por el cronista contemporáneo Ibn Hiŷŷī (d. 816/1413 abre una perspectiva interesante para explicar la selección de documentos relacionados con Šaraf al-Dīn, que estuvo involucrado en un enorme asunto de corrupción.

  16. ¿Cartografía antigua o Cartografía histórica?

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    Crespo Sanz, Antonio

    2011-12-01

    Full Text Available The terms related to the History of Cartography need to be revised in the light of the confusion and ambiguities that have been brought about. Many map publications or catalogues use the term historical cartography to characterize their content, although the name old cartography should be used instead; and literal translation of some expressions taken from other languages yields unsuccessful results. The new technologies have lead to a singular development and dissemination of Cartography, its thrust also bearing upon old cartography. The main archives and libraries publish their collections with high resolution and their documents may be analyzed with more manageable and friendly tools, but there are not many theoretical studies about their nature or aims and there are no proposals to reformulate the basic definitions linked to the History of Cartography either. Along these lines we intend to analyze and reflect upon the vocabulary pertaining to this discipline, thus easing the task of those addressing themselves to old maps.

    [es] Los términos relacionados con la Historia de la Cartografía necesitan ser revisados, a tenor de las confusiones y ambigüedades que se vienen produciendo. Muchas publicaciones o catálogos de mapas utilizan el término cartografía histórica para definir su contenido, cuando debería utilizarse la expresión cartografía antigua, y la traducción literal de algunas expresiones tomadas de otros idiomas, arroja resultados poco afortunados. Las nuevas tecnologías han provocado un desarrollo y una difusión inusitados de la Cartografía, y su empuje afecta a la cartografía antigua. Los principales archivos y bibliotecas publican sus fondos con gran resolución y sus documentos pueden ser analizados con herramientas más ágiles y amigables, pero no abundan los estudios teóricos sobre su naturaleza u objetivos, ni existen propuestas para reformular las definiciones básicas vinculadas a la Historia de la

  17. CONTRIBUCIÓN DE LAS ENTIDADES DE “ECONOMÍA SOCIAL” A LA GESTIÓN EFICIENTE DEL AGUA PARA USO AGRÍCOLA: SITUACIÓN EN LA REGIÓN DE MURCIA/CONTRIBUTION OF THE ENTITIES OF “SOCIAL ECONOMY” TO THE EFFICIENT MANAGEMENT OF WATER FOR AGRICULTURAL USE: SITUATION IN THE REGION OF MURCIA

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    Narciso ARCAS LARIO

    2007-01-01

    Full Text Available AbstractEn la literatura abundan los trabajos dirigidos a caracterizar las entidades que integran la “Economía Social” en España y a cuantificar su contribución a los diferentes sectores económicos y, en especial, al sector agroalimentario. Sin embargo, estos trabajos no se han hecho eco de la importancia de estas organizaciones para la gestión de un recurso tan fundamental para el sector agrario como el agua, y del papel que en ella juegan las Comunidades de Regantes (CCRR, sobre todo, junto a las entidades asociativas agrarias (Cooperativas Agrarias y Sociedades Agrarias de Transformación. Aunque apenas contempladas como entidades de “Economía Social” en los estudios publicados sobre este tipo de organizaciones, a las Comunidades de Regantes (CCRR corresponde la función prioritaria de distribuir y administrar de una manera eficiente las aguas asignadas entre sus miembros. A ello, también pueden contribuir otras organizaciones ampliamente reconocidas dentro de la “Economía Social” como es el caso de las Cooperativas Agrarias y las Sociedades Agrarias de Transformación. En este contexto, el objetivo de este trabajo es, de un lado, poner de relieve que las CCRR comparten los principios de las empresas de “Economía Social”, y resaltar sus características con relación a las Cooperativas Agrarias y SAT. Por otra parte, se identifican los componentes de la eficiencia en la gestión del agua para uso agrícola y se analiza la contribución que las CCRR y las entidades asociativas agrarias de la Región de Murcia realizan a la mejora de la misma a través de los diversos servicios que prestan a sus socios (formación, información, asesoramiento, financiación, etc. /In the literature there are many works directed at characterizing those entities which form the “Social Economy” in Spain and at quantifying their contribution to the different economic sectors, especially the agricultural food sector. However, these works

  18. Escuela elemental Osborn-Road, (U.S.A.

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    Sherwood, Mills y Smith, Arquitectos

    1963-02-01

    estudios que cursan. En el conjunto total se encuentran 13 salas para clases, repartidas en 3 bloques distintos, 6 aulas para enseñanza primaria, 6 para el grado medio y 1 para el jardín de infancia. La disposición en planta nos muestra la ordenación de los diversos bloques, que ocupan aproximadamente 3.500 m2. El bloque dedicado a la enseñanza media se encuentra en la parte norte del terreno, y los del grado primario y pre-primario, a izquierda y derecha, respectivamente. Las separaciones entre los diversos bloques acentuadas por los patios de recreo y zonas de juegos cubiertas crean una zona circundante exterior agradable para fines docentes y permiten el posible crecimiento de los bloques, ligados a uno central en el que se encuentran los servicios generales. En las zonas tranquilas están las oficinas de administración, el servicio médico- sanitario, salas de visitas, la biblioteca, etc. Los edificios, con sus grandes cristaleras, dan la sensación de estar fundidos en el paisaje que los rodea. Los muros emplean módulos dobles y sencillos alternados. En ellos se han utilizado ladrillos corrientes y elementos prefabricados de hormigón con una disposición en diversos planos formando ángulos rectos y obtusos. Las cubiertas son planas y no tienen ninguna inclinación. En el interior abundan los cristales amplios, y entre sus instalaciones destacan la biblioteca, con sus muros de cristal; los comedores, los gimnasios y el salón de reuniones que sirve para conferencias y representaciones teatrales. Las clases son alegres y bien iluminadas, con orientación al exterior, y están provistas de pupitres individuales. Los tabiques y techos interiores poseen aislamiento acústico para contribuir al logro de una mayor independencia.

  19. El poder de nominar: Los nombres de los niños y niñas mapuche como campo de disputa O poder de nomear: Os nomes de crianças mapuche como campo de disputa The power of nominating: Mapuche children's names as a field of dispute

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    Andrea Szulc

    2012-12-01

    Full Text Available En la provincia del Neuquén abundan casos en que personal del Registro Civil o del sistema educativo ha objetado la inscripción o utilización del nombre mapuche de un niño/a. Al mismo tiempo, entre la población mapuche se vienen registrando iniciativas individuales y estrategias colectivas de autoreconocimiento, recuperación cultural y demandas de reconocimiento estatal del modo mapuche de elección y atribución de los nombres, y de su particular ontología. Como una piedra de toque, los nombres de estos niños nos permitirán conocer las dispares definiciones de lo mapuche, en ocasiones contradictorias, que promueven diversos actores y agencias en la provincia del Neuquén. Veremos cómo a través de sus prácticas los niños y los "otros" -adultos, comunidades y organizaciones mapuche, iglesias católica y evangélicas, docentes y funcionarios estatales- hacen del acto de nominar una de las arenas en las cuales crecientemente se disputa la identidad de los niños mapuche del Neuquén.Em Neuquén, província localizada no sul da Argentina, é comum que o sistema educativo e o Registro Civil neguem a inscrição ou cadastramento de nomes mapuches de crianças e jovens. Simultaneamente, a população mapuche vem desenvolvendo, por meio de iniciativas individuais e estratégias coletivas, um processo de auto-reconhecimento e revitalização cultural, demandando ao Estado o reconhecimento da ontologia particular, modos de escolha e de atribuição dos nomes em língua mapuche. Assim, a análise desta questão nos permitirá conhecer definições díspares do mapuche, por vezes contraditórias, que promovem diferentes atores e agências na província de Neuquén. Veremos como através das práticas das crianças e dos "outros" -adultos, comunidades e organizações mapuche, igrejas católica e evangélica, docentes e funcionários do Estado- o ato de colocar nomes se torna crescentemente uma das arenas de disputa da identidade das crian

  20. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements

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    Morales Maria E

    2005-02-01

    Full Text Available Abstract Background Of the major families of long terminal repeat (LTR retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT, RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs

  1. Compounds Derived from the Bhutanese Daisy, Ajania nubigena, Demonstrate Dual Anthelmintic Activity against Schistosoma mansoni and Trichuris muris

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    Pearson, Mark S.; Giacomin, Paul R.; Becker, Luke; Sotillo, Javier; Pickering, Darren

    2016-01-01

    Background Whipworms and blood flukes combined infect almost one billion people in developing countries. Only a handful of anthelmintic drugs are currently available to treat these infections effectively; there is therefore an urgent need for new generations of anthelmintic compounds. Medicinal plants have presented as a viable source of new parasiticides. Ajania nubigena, the Bhutanese daisy, has been used in Bhutanese traditional medicine for treating various diseases and our previous studies revealed that small molecules from this plant have antimalarial properties. Encouraged by these findings, we screened four major compounds isolated from A. nubigena for their anthelmintic properties. Methodology/Principal Findings Here we studied four major compounds derived from A. nubigena for their anthelmintic properties against the nematode whipworm Trichuris muris and the platyhelminth blood fluke Schistosoma mansoni using the xWORM assay technique. Of four compounds tested, two compounds—luteolin (3) and (3R,6R)-linalool oxide acetate (1)—showed dual anthelmintic activity against S. mansoni (IC50 range = 5.8–36.9 μg/mL) and T. muris (IC50 range = 9.7–20.4 μg/mL). Using scanning electron microscopy, we determined luteolin as the most efficacious compound against both parasites and additionally was found effective against the schistosomula, the infective stage of S. mansoni (IC50 = 13.3 μg/mL). Luteolin induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. Our in vivo assessment of luteolin (3) against T. muris infection at a single oral dosing of 100 mg/kg, despite being significantly (27.6%) better than the untreated control group, was markedly weaker than mebendazole (93.1%) in reducing the worm burden in mice. Conclusions/Significance Among the four compounds tested, luteolin demonstrated the best broad-spectrum activity against two different helminths—T. muris and S. mansoni—and was

  2. An integrated pipeline for next generation sequencing and annotation of the complete mitochondrial genome of the giant intestinal fluke, Fasciolopsis buski (Lankester, 1857 Looss, 1899

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    Devendra Kumar Biswal

    2013-11-01

    Full Text Available Helminths include both parasitic nematodes (roundworms and platyhelminths (trematode and cestode flatworms that are abundant, and are of clinical importance. The genetic characterization of parasitic flatworms using advanced molecular tools is central to the diagnosis and control of infections. Although the nuclear genome houses suitable genetic markers (e.g., in ribosomal (r DNA for species identification and molecular characterization, the mitochondrial (mt genome consistently provides a rich source of novel markers for informative systematics and epidemiological studies. In the last decade, there have been some important advances in mtDNA genomics of helminths, especially lung flukes, liver flukes and intestinal flukes. Fasciolopsis buski, often called the giant intestinal fluke, is one of the largest digenean trematodes infecting humans and found primarily in Asia, in particular the Indian subcontinent. Next-generation sequencing (NGS technologies now provide opportunities for high throughput sequencing, assembly and annotation within a short span of time. Herein, we describe a high-throughput sequencing and bioinformatics pipeline for mt genomics for F. buski that emphasizes the utility of short read NGS platforms such as Ion Torrent and Illumina in successfully sequencing and assembling the mt genome using innovative approaches for PCR primer design as well as assembly. We took advantage of our NGS whole genome sequence data (unpublished so far for F. buski and its comparison with available data for the Fasciola hepatica mtDNA as the reference genome for design of precise and specific primers for amplification of mt genome sequences from F. buski. A long-range PCR was carried out to create an NGS library enriched in mt DNA sequences. Two different NGS platforms were employed for complete sequencing, assembly and annotation of the F. buski mt genome. The complete mt genome sequences of the intestinal fluke comprise 14,118 bp and is thus the

  3. An integrated pipeline for next generation sequencing and annotation of the complete mitochondrial genome of the giant intestinal fluke, Fasciolopsis buski (Lankester, 1857) Looss, 1899.

    Science.gov (United States)

    Biswal, Devendra Kumar; Ghatani, Sudeep; Shylla, Jollin A; Sahu, Ranjana; Mullapudi, Nandita; Bhattacharya, Alok; Tandon, Veena

    2013-01-01

    Helminths include both parasitic nematodes (roundworms) and platyhelminths (trematode and cestode flatworms) that are abundant, and are of clinical importance. The genetic characterization of parasitic flatworms using advanced molecular tools is central to the diagnosis and control of infections. Although the nuclear genome houses suitable genetic markers (e.g., in ribosomal (r) DNA) for species identification and molecular characterization, the mitochondrial (mt) genome consistently provides a rich source of novel markers for informative systematics and epidemiological studies. In the last decade, there have been some important advances in mtDNA genomics of helminths, especially lung flukes, liver flukes and intestinal flukes. Fasciolopsis buski, often called the giant intestinal fluke, is one of the largest digenean trematodes infecting humans and found primarily in Asia, in particular the Indian subcontinent. Next-generation sequencing (NGS) technologies now provide opportunities for high throughput sequencing, assembly and annotation within a short span of time. Herein, we describe a high-throughput sequencing and bioinformatics pipeline for mt genomics for F. buski that emphasizes the utility of short read NGS platforms such as Ion Torrent and Illumina in successfully sequencing and assembling the mt genome using innovative approaches for PCR primer design as well as assembly. We took advantage of our NGS whole genome sequence data (unpublished so far) for F. buski and its comparison with available data for the Fasciola hepatica mtDNA as the reference genome for design of precise and specific primers for amplification of mt genome sequences from F. buski. A long-range PCR was carried out to create an NGS library enriched in mt DNA sequences. Two different NGS platforms were employed for complete sequencing, assembly and annotation of the F. buski mt genome. The complete mt genome sequences of the intestinal fluke comprise 14,118 bp and is thus the shortest

  4. The Schistosoma mansoni tegumental-allergen-like (TAL protein family: influence of developmental expression on human IgE responses.

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    Colin M Fitzsimmons

    Full Text Available BACKGROUND: A human IgE response to Sm22.6 (a dominant IgE target in Schistosoma mansoni is associated with the development of partial immunity. Located inside the tegument, the molecule belongs to a family of proteins from parasitic platyhelminths, the Tegument-Allergen-Like proteins (TALs. In addition to containing dynein-light-chain domains, these TALs also contain EF-hand domains similar to those found in numerous EF-hand allergens. METHODOLOGY/PRINCIPAL FINDINGS: S. mansoni genome searches revealed 13 members (SmTAL1-13 within the species. Recent microarray data demonstrated they have a wide range of life-cycle transcriptional profiles. We expressed SmTAL1 (Sm22.6, SmTAL2, 3, 4, 5 and 13 as recombinant proteins and measured IgE and IgG4 in 200 infected males (7-60 years from a schistosomiasis endemic region in Uganda. For SmTAL1 and 3 (transcribed in schistosomula through adult-worms and adult-worms, respectively and SmTAL5 (transcribed in cercariae through adult-worms, detectable IgE responses were rare in 7-9 year olds, but increased with age. At all ages, IgE to SmTAL2 (expressed constitutively, was rare while anti-SmTAL2 IgG4 was common. Levels of IgE and IgG4 to SmTAL4 and 13 (transcribed predominantly in the cercariae/skin stage were all low. CONCLUSIONS: We have not measured SmTAL protein abundance or exposure in live parasites, but the antibody data suggests to us that, in endemic areas, there is priming and boosting of IgE to adult-worm SmTALs by occasional death of long-lived worms, desensitization to egg SmTALs through continuous exposure to dying eggs and low immunogenicity of larval SmTALs due to immunosuppression in the skin by the parasite. Of these, it is the gradual increase in IgE to the worm antigens that parallels age-dependent immunity seen in endemic areas.

  5. Avaliação da comunidade de macroinvertebrados aquáticos como ferramenta para o monitoramento de um reservatório na bacia do rio Pitangui, Paraná, Brasil

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    Ivana F Barbola

    2011-06-01

    Full Text Available Os macroinvertebrados bentônicos e nectônicos representam elementos importantes na estrutura e funcionamento dos ecossistemas aquáticos e sua distribuição é influenciada pela natureza química do substrato, composição da vegetação e profundidade da lâmina d'água. O conhecimento desta fauna contribui para a avaliação da qualidade da água e a elaboração de ações visando à conservação da biodiversidade. No presente estudo foram avaliadas diferentes medidas bióticas da comunidade de invertebrados da represa de Alagados, importante manancial da cidade de Ponta Grossa, no Paraná. Em cinco diferentes pontos de amostragem, foram coletados 18.473 exemplares de macroinvertebrados aquáticos ou semi-aquáticos, pertencentes a 46 táxons dos filos Annelida (Hirudinea e Oligochaeta, Mollusca (Gastropoda, Platyhelminthes (Turbellaria, Nematoda e Arthropoda (Arachnida, Crustacea e Insecta. Esta comunidade foi constituída predominantemente por organismos predadores (45,7% dos táxons amostrados, seguidos de coletores e/ou filtradores (23,9%; raspadores (15,2%, fragmentadores (13% e detritívoros (2,2%. De modo geral, os índices de diversidade (H' e equitabilidade (J foram significativamente baixos para os cinco locais investigados, com H' variando de 0,3301 a 1,0396. Quanto à tolerância dos organismos à poluição orgânica, alguns táxons mais sensíveis foram muito raros (Plecoptera ou em baixa frequência (Trichoptera e Ephemeroptera. Entre os grupos mais resistentes a ambientes poluídos estão os Chironomidae e os Hirudinea, ambos bastante comuns nas amostras de Alagados. Este estudo reforça a importância da análise de bioindicadores na avaliação da qualidade de água para consumo humano e também para a conservação de ecossistemas, considerando que um programa de monitoramento ambiental deve integrar medidas físicas, químicas e biológicas.

  6. Water quality and potamoplankton evaluation of the Nile River in Upper Egypt

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    Ahmed Mohamed El-Otify

    2015-06-01

    Full Text Available Aim: The composition, abundance, community structure of potamoplankton and major physical and chemical variables of the Nile water in Upper Egypt were investigated to assess its status in different seasons during 2007.MethodsWater samples were collected seasonally during 2007 from six investigated sites from variable depths at levels of 0, 2.5 and 5 m. The area of this investigation is defined as the southern 120 Km of the main stream of the Nile in Upper Egypt (24° 04’ – 25° 00’ latitudes and 32° 51’ – 32° 54’ longitudes, downstream of Aswan Old Dam.ResultsAltogether, 121 potamoplankton species, of which 85 related to phytoplankton and 36 appertaining to zooplankton were recorded. Most numerous phytoplankton were Chlorophyceae (42 species followed by Bacillariophyceae (30 species. Cyanobacteria and Dinophyceae were less numerous with only 11 and 2 species, respectively. Zooplankton species were mainly belonging to three systematic groups namely; Rotifera (24 species, Copepoda (3 species and Cladocera (9 species. Besides, other rare zooplankton including Platyhelminthes, Nemata and Ciliophora were sparsely encountered. The main hydrological conditions characterizing the investigated area include water level fluctuations (˂82 - ˃85 m above sea level, relatively high current velocity (0.8 - 1.3 m sec–1 and disposal of wastewater. Plankton populations were variably but rather weakly dependent on the major nutrients due to their excessive availability in accessible form for uptake by the producers. For phytoplankton, the community structure was categorized in relation to temperature, pH, SO42– and Mg2+. For zooplankton, the community structure was categorized in relation to conductivity as well as Mg2+. Sampling intervals were inadequate to demonstrate the existing successional pattern of the Nile potamoplankton community. Alterations in the phytoplankton community structure accompanied changes in water temperature represented

  7. Specific retention of the protostome-specific PsGEF may parallel with the evolution of mushroom bodies in insect and lophotrochozoan brains

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    Kohno Keigo

    2009-05-01

    Full Text Available Abstract Background Gene gain and subsequent retention or loss during evolution may be one of the underlying mechanisms involved in generating the diversity of metazoan nervous systems. However, the causal relationships acting therein have not been studied extensively. Results We identified the gene PsGEF (protostome-specific GEF, which is present in all the sequenced genomes of insects and limpet but absent in those of sea anemones, deuterostomes, and nematodes. In Drosophila melanogaster, PsGEF encodes a short version of a protein with the C2 and PDZ domains, as well as a long version with the C2, PDZ, and RhoGEF domains through alternative splicing. Intriguingly, the exons encoding the RhoGEF domain are specifically deleted in the Daphnia pulex genome, suggesting that Daphnia PsGEF contains only the C2 and PDZ domains. Thus, the distribution of PsGEF containing the C2, PDZ, and RhoGEF domains among metazoans appears to coincide with the presence of mushroom bodies. Mushroom bodies are prominent neuropils involved in the processing of multiple sensory inputs as well as associative learning in the insect, platyhelminth, and annelid brains. In the adult Drosophila brain, PsGEF is expressed in mushroom bodies, antennal lobe, and optic lobe, where it is necessary for the correct axon branch formation of alpha/beta neurons in mushroom bodies. PsGEF genetically interacts with Rac1 but not other Rho family members, and the RhoGEF domain of PsGEF induces actin polymerization in the membrane, thus resulting in the membrane ruffling that is observed in cultured cells with activated forms of Rac. Conclusion The specific acquisition of PsGEF by the last common ancestor of protostomes followed by its retention or loss in specific animal species during evolution demonstrates that there are some structural and/or functional features common between insect and lophotrochozoan nervous systems (for example, mushroom bodies, which are absent in all deuterostomes

  8. Molecular characterization of Fasciola hepatica from Sardinia based on sequence analysis of genomic and mitochondrial gene markers.

    Science.gov (United States)

    Farjallah, Sarra; Ben Slimane, Badreddine; Piras, Cristina Maria; Amor, Nabil; Garippa, Giovanni; Merella, Paolo

    2013-11-01

    The aim of the present study is to investigate for the first time the genetic diversity of samples identified morphologically as Fasciola hepatica (Platyhelminthes: Trematoda: Digenea) (n=66) from sheep and cattle from two localities of Sardinia and to compare them with available data from other localities by partial sequences of the first (ITS-1), the 5.8S, and second (ITS-2) Internal Transcribed Spacers (ITS) of nuclear ribosomal DNA (rDNA) genes, the mitochondrial cytochrome c oxidase subunit I (COI), and nicotinamide adenine dinucleotide dehydrogenase subunit I (ND1) genes. Comparison of the sequences from Sardinia with sequences of Fasciola spp. from GenBank confirmed that all samples belong to the species F. hepatica. The nucleotide sequencing of ITS rDNA showed no nucleotide variation in the ITS-1, 5.8S and ITS-2 rDNA sequences among all Sardinian samples, comparing with two ITS-2 haplotypes in standard F. hepatica, showing a substitution C/T in 20 position 859, reported previously from Tunisia, Algeria, Australia, Uruguay and Spain. The present study shows that in Sardinian sheep and cattle there is the most frequent haplotype (FhITS-H1) of F. hepatica species from South Europe. Considering NDI sequences, the phylogenetic trees showed reliable grouping among the haplotypes of F. hepatica from Sardinia and the mitochondrial lineage I, including the main N1 haplotype, observed previously from Europe (Russia, Belarus, Ukraine and Bulgaria), Armenia, West Africa (Nigeria), America (Uruguay and USA), Asia (Turkey, Japan, and China), Georgia, Turkmenistan, Azerbaijan and Australia. Furthermore, common haplotypes FhCOI-H1 and FhCOI-H2 of F. hepatica from Sardinia also corresponded mostly to the first lineage including the main C1 haplotype reported previously from Eastern European and Western Asian populations, they belonged just to a phylogenically distinguishable clade, as F. hepatica from Australia, France, Turkey, Uruguay, Russia, Armenia, Ukraine, Belarus

  9. The diterpenoid 7-keto-sempervirol, derived from Lycium chinense, displays anthelmintic activity against both Schistosoma mansoni and Fasciola hepatica.

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    Jennifer Edwards

    2015-03-01

    Full Text Available BACKGROUND: Two platyhelminths of biomedical and commercial significance are Schistosoma mansoni (blood fluke and Fasciola hepatica (liver fluke. These related trematodes are responsible for the chronic neglected tropical diseases schistosomiasis and fascioliasis, respectively. As no vaccine is currently available for anti-flukicidal immunoprophylaxis, current treatment is mediated by mono-chemical chemotherapy in the form of mass drug administration (MDA (praziquantel for schistosomiasis or drenching (triclabendazole for fascioliasis programmes. This overreliance on single chemotherapeutic classes has dramatically limited the number of novel chemical entities entering anthelmintic drug discovery pipelines, raising significant concerns for the future of sustainable blood and liver fluke control. METHODOLOGY/ PRINCIPLE FINDINGS: Here we demonstrate that 7-keto-sempervirol, a diterpenoid isolated from Lycium chinense, has dual anthelmintic activity against related S. mansoni and F. hepatica trematodes. Using a microtiter plate-based helminth fluorescent bioassay (HFB, this activity is specific (Therapeutic index = 4.2, when compared to HepG2 cell lines and moderately potent (LD50 = 19.1 μM against S. mansoni schistosomula cultured in vitro. This anti-schistosomula effect translates into activity against both adult male and female schistosomes cultured in vitro where 7-keto-sempervirol negatively affects motility/behaviour, surface architecture (inducing tegumental holes, tubercle swelling and spine loss/shortening, oviposition rates and egg morphology. As assessed by the HFB and microscopic phenotypic scoring matrices, 7-keto-sempervirol also effectively kills in vitro cultured F. hepatica newly excysted juveniles (NEJs, LD50 = 17.7 μM. Scanning electron microscopy (SEM evaluation of adult F. hepatica liver flukes co-cultured in vitro with 7-keto-sempervirol additionally demonstrates phenotypic abnormalities including breaches in tegumental

  10. Matrotrophy and placentation in invertebrates: a new paradigm.

    Science.gov (United States)

    Ostrovsky, Andrew N; Lidgard, Scott; Gordon, Dennis P; Schwaha, Thomas; Genikhovich, Grigory; Ereskovsky, Alexander V

    2016-08-01

    Matrotrophy, the continuous extra-vitelline supply of nutrients from the parent to the progeny during gestation, is one of the masterpieces of nature, contributing to offspring fitness and often correlated with evolutionary diversification. The most elaborate form of matrotrophy-placentotrophy-is well known for its broad occurrence among vertebrates, but the comparative distribution and structural diversity of matrotrophic expression among invertebrates is wanting. In the first comprehensive analysis of matrotrophy across the animal kingdom, we report that regardless of the degree of expression, it is established or inferred in at least 21 of 34 animal phyla, significantly exceeding previous accounts and changing the old paradigm that these phenomena are infrequent among invertebrates. In 10 phyla, matrotrophy is represented by only one or a few species, whereas in 11 it is either not uncommon or widespread and even pervasive. Among invertebrate phyla, Platyhelminthes, Arthropoda and Bryozoa dominate, with 162, 83 and 53 partly or wholly matrotrophic families, respectively. In comparison, Chordata has more than 220 families that include or consist entirely of matrotrophic species. We analysed the distribution of reproductive patterns among and within invertebrate phyla using recently published molecular phylogenies: matrotrophy has seemingly evolved at least 140 times in all major superclades: Parazoa and Eumetazoa, Radiata and Bilateria, Protostomia and Deuterostomia, Lophotrochozoa and Ecdysozoa. In Cycliophora and some Digenea, it may have evolved twice in the same life cycle. The provisioning of developing young is associated with almost all known types of incubation chambers, with matrotrophic viviparity more widespread (20 phyla) than brooding (10 phyla). In nine phyla, both matrotrophic incubation types are present. Matrotrophy is expressed in five nutritive modes, of which histotrophy and placentotrophy are most prevalent. Oophagy, embryophagy and

  11. Macrobenthic fauna community in the Middle Songkhla Lake, Southern Thailand

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    Angsupanich, S.

    2005-02-01

    Full Text Available A bimonthly investigation of macrobenthic fauna at the area from Ban Pak Khat to Ban Leam Chong Thanon in the Inner Songkhla Lake from February 1998 to February 1999 was undertaken to determine the species richness and abundance. A total of 7 phyla and 161 species were identified. Annelida (58 species, Arthropoda (64 species and Mollusca (23 species were the major phyla while Nemertea (1 species, Platyhelminthes (1 species, Cnidaria (4 species and Chordata (10 species were the minor. Fifty-seven speciesof Polychaete annelids were found. The highest species richness (14 species was in the Nereididae Family, of which Ceratonereis burmensis and Namalycastis indica were predominant. Nephtys sp. and Heteromastus sp. were not so highly abundant but appeared at almost all stations through every sampling month, while Prionospio cirrifera and Pseudopolydora kempi were found in higher densities but with narrower distribution. Ficopomatus sp. and unidentified Terebellidae were not commonly found, but occasionally reached a high density. Amphipods gave the highest species richness (22 species, with Photis longicaudata distributed widely and in all months. Five species of Tanaidaceans were found with Apseudes sapensis the second most dominant (max. 5044 individuals m-2 in February in the overall fauna. Isopoda were not as densely found as tanaidaceans but there were many species (18 species. Cyathura sp.1 was the most dominant isopod. Brachidontes arcuatulus was the most dominant bivalve (max. 29449 individuals m-2 in April, especially at stations with a sand-gravel substrate. The mean density of total macrobenthic fauna among stations ranged from 920 to 10620 ind. m-2 while the monthly densities ranged from 1520 to 6160 ind.m-2. The mean density of macrobenthic fauna was highest in the dry season (April. The species richness among stations ranged from65 to 105 species while varying from 81 to 112 species during the different months. The highest species

  12. Editorial

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    Esteban González Pérez

    2013-07-01

    étrico sobre la producción científica, las tecnologías móviles o digitales en las bibliotecas, el papel del profesional en bibliotecología para la animación a la lectura y la diseminación de la información, entre otros temas, aportan nuevos tópicos de reflexión, a una de las disciplinas que se mantiene con mayor dinamismo y cambio en la sociedad de la información como lo es la bibliotecología.La investigación científica aporta nuevas maneras de comprender e interpretar el mundo en que vivimos. Es por medio del avance en la ciencia y la tecnología como el ser humano busca las respuestas a interrogantes que requieren ser resueltas para mejorar la calidad de vida y la conservación del hábitat que nos rodea. Además, para brindar soluciones innovadoras a los múltiples retos que enfrenta el profesional de la información en una sociedad en que abundan las ofertas informativas. Uno de los retos más importantes, es agregar valor a la información para que esta sirva a las necesidades específicas de cada usuario, considerando sus posibilidades de interpretación, uso y beneficio que le pueda aportar para incidir en su diario quehacer.La revista e-Ciencias de la Información anima a todas las personas que ejercen en la profesión bibliotecológica nacional e internacional, a enviar sus investigaciones, para que sean valoradas por nuestros especialistas y que sean publicadas en las próximas ediciones. Además, a todas las personas que se desarrollan de la mano de la información y la tecnología en otras áreas del conocimiento y que, con esfuerzo y dedicación, hayan elaborado un documento original para publicar, se les invita a que puedan sumarse a alguna de las futuras entregas de la revista.

  13. Cholestasis induced by total parenteral nutrition: effects of the addition of Taurine (Tauramin® on hepatic function parameters; possible synergistic action of structured lipids (SMOFlipid® Colestasis inducida por nutrición parenteral total: efecto de la adición de Taurina (Tauramin® sobre los parámetros de función hepática; posible acción sinérgica de lípidos estructurados (SMOFlipid®

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    J. González-Contreras

    2012-12-01

    recibieron dietas homogéneas en kcal y macronutrientes. En la Fase 2, 21 pacientes del grupo A recibieron lípidos estructurados (SMOFlipid®; mientras que 20 del grupo B recibieron MCT/LCT soja (mezcla física o estructurada. Las diferencias no se han podido obviar en un estudio retrospectivo. Se rescataron de Nutridata® y Servolab® los parámetros analíticos en tres momentos (Inicio, Intermedio y Final. Utilizando SPSS® se compararon según Test de Wilcoxon para valores intermomentos (p < 0,05. Resultados: Hubo disminución significativa de AST, ALT y GGT tras la introducción de Taurina; Bilirrubina desciende sin significación. Los valores obtenidos para GGT en el Grupo A fueron (Media(σ/mediana: Inicio 48,6 (23,1/46; Intermedio 473,7 (276,2/438 y Final 328,9 (190,4/305. Destacamos que el valor medio de GGT disminuye un 30,56% tras adición de Taurina; mientras en su ausencia se elevan de todos los parámetros, aumentando un 45,36% la media de GGT. Conclusión: Estos resultados abundan en el papel hepatoprotector de la Taurina, y apoyan su utilización en situación de colestasis inducida por NPT. Asumimos la posibilidad de que la diferencia de perfil entre SMOF y las mezclas MCT/LCT haya influido como efecto combinado utilizado junto a taurina.

  14. Anatomopathological study of parrot pufferfish Colomesus psittacus parasitized by the aspidogastrean Rohdella sp. Estudo anatomopatológico do peixe baiacu papagaio Colomesus psittacus parasitado pelo aspidogastrea Rohdella sp.

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    Michele Velasco Oliveira da Silva

    2013-03-01

    Full Text Available Aspidogastrea are globally-distributed parasites of the class Trematoda, which have been described as pathogens of a range of aquatic organisms, in marine and freshwater environments. The principal morphological characteristic of the group is an adhesive ventral disc, which is responsible for fixing the parasite to the host organism. In this study, 112 specimens of Colomesus psittacus from the municipality of Cametá, in the state of Pará (Brazil, were necropsied. Platyhelminthes of the genus Rohdella attached to the mucous membrane of the fish's intestine by the adhesive disc were observed. Fragments of parasitized tissue were fixed in Davidson solution and then processed and stained with hematoxylin-eosin. Other fragments were fixed in glutaraldehyde, processed and observed under a scanning electron microscope. The prevalence of the parasite was 76.4%, mean intensity of infection was 8.0 and mean abundance was 6.2. The parasitism provoked chronic enteritis with diffused inflammatory infiltration. The adherence of the parasite to the mucous membrane of the intestine resulted in strangulation and hyperplasia of the region, as well as causing hypertrophy of the muscle of the mucous membrane. The present study describes the anatomopathological and ultrastructural aspects of the parasitism of the intestine of C. psittacus by Rohdella sp.Os Aspidogastreas são parasitos da classe Trematoda, distribuídos globalmente e têm sido descritos como patógenos em uma gama de organismos aquáticos de ambientes marinhos e de água doce. A principal característica morfológica do grupo é um disco adesivo na região ventral responsável pela fixação do parasito no organismo hospedeiro. Neste estudo, 112 espécimes de Colomesus psittacus provenientes do município de Cametá, no estado do Pará (Brasil, foram necropsiados. Foram observados platelmintos do gênero Rohdella aderidos à mucosa intestinal através do disco adesivo. Fragmentos de tecido com

  15. Cross-disciplinary approaches for measuring parasitic helminth viability and phenotype

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    Emily Peak

    2011-06-01

    Full Text Available Parasitic worms (helminths within the Phyla Nematoda and Platyhelminthes are responsible for some of the most debilitating and chronic infectious diseases of human and animal populations across the globe. As no subunit vaccine for any parasitic helminth is close to being developed, the frontline strategy for intervention is administration of therapeutic, anthelmintic drugs. Worryingly, and unsurprising due to co-evolutionary mechanisms, many of these worms are developing resistance to the limited compound classes currently being used. This unfortunate reality has led to a renaissance in next generation anthelmintic discovery within both academic and industrial sectors. However, a major bottleneck in this process is the lack of quantitative methods for screening large numbers of small molecules for their effects on the whole organism. Development of methodologies that can objectively and rapidly distinguish helminth viability or phenotype would be an invaluable tool in the anthelmintic discovery pipeline. Towards this end, we describe how several basic techniques currently used to assess single cell eukaryote viability have been successfully applied to parasitic helminths. We additionally demonstrate how some of these methodologies have been adopted for high-throughput use and further modified for assessing worm phenotype. Continued development in this area is aimed at increasing the rate by which novel anthelmintics are identified and subsequently translated into everyday, practical applications.Vermes parasíticos (helmintos dos filos Nematoda e Platelmintos são responsáveis por algumas das doenças infecciosas crônicas e mais debilitantes das populações humana e animal em todo o globo. Já que nenhuma vacina está prestes a ser desenvolvida para nenhum parasita helmíntico, a frente estratégica de intervenção é a administração de drogas terapêuticas anti-helmínticas. De maneira preocupante, e não surpreendente devido a mecanismos

  16. Construction of a medicinal leech transcriptome database and its application to the identification of leech homologs of neural and innate immune genes

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    Wincker Patrick

    2010-06-01

    evolutionarily conserved sequences, representing all known pathways involved in these important functions. Conclusions The sequences obtained for Hirudo transcripts represent the first major database of genes expressed in this important model system. Comparison of translated open reading frames (ORFs with the other openly available leech datasets, the genome and transcriptome of Helobdella robusta, shows an average identity at the amino acid level of 58% in matched sequences. Interestingly, comparison with other available Lophotrochozoans shows similar high levels of amino acid identity, where sequences match, for example, 64% with Capitella capitata (a polychaete and 56% with Aplysia californica (a mollusk, as well as 58% with Schistosoma mansoni (a platyhelminth. Phylogenetic comparisons of putative Hirudo innate immune response genes present within the Hirudo transcriptome database herein described show a strong resemblance to the corresponding mammalian genes, indicating that this important physiological response may have older origins than what has been previously proposed.

  17. Autoimagen y salud en el comercio de la belleza

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    Berrocal-Revueltas Manuela

    2012-06-01

    las mamas, para obtener volumen.Se difunden en los tejidos, siendo difícilsu extracción. Pueden ser rechazados por el organismo,producir granulomas como reacción acuerpo extraño en forma inmediata a su instalacióno a largo plazo. Sus posibles secuelas odefectos son impredecibles. Abundan por tenerun bajo costo. A este grupo pertenece la siliconalíquida (polysiloxane ó dimetilpolysiloxaneretirada a nivel mundial para uso sanitario desdela década de los 60 del siglo XX. Tampocodeben utilizarse el polyacrylamide (polimeros,el polimetilmetacrilato (PMMA, el polietileno yel silicio + O2, entre otros.El profesional de la salud especializado enmedicina estética y reconstructiva debe valoraren conjunto al paciente que desea usarmateriales de relleno. Son recomendableslos implantes biol ógicos temporales ,proteínas fabricadas a partir de moléculasbiodegradables inyectadas en la cara o enlas manos para rellenar y recuperar volumeno atenuar las arrugas. Algunos requierende prueba de sensibilidad, antes de seraplicados para saber si son bien tolerados porel organismo. Son muy utilizados en paísesdesarrollados. Son de alto costo y su efectoes temporal o transitorio. Hacen parte de estegrupo el colágeno, el ácido hialurónico, el ácidohialuronico por biofermentación, el plasma +Vitamina C.Son seguros al ser aplicados por profesio-nalesespecialistas, LOS IMPLANTES AUTÓLOGOSTEMPORALES. Los tejidos pueden ser transferidosde un lugar a otro del organismo, con elrecurso de técnicas quirúrgicas bien definidas.Pueden ser permanentes ó transitorias deacuerdo con la clase de tejido injertado. Lalipoinyección o transferencia de grasa o injertode grasa se ha popularizado. Los injertos decartílago ó hueso para mejorar el contorno delesqueleto facial, ofrecen buenos resultados.El profesional de la salud especializado en cirugíaestética, que asume el papel de orientador,que ejecuta procedimientos e intervencionesquirúrgicas, debe tener un conocimiento claroy objetivo

  18. EDITORIAL

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    Jesús Alberto Andrade

    2007-09-01

    que provienen de distintos países de Iberoamérica, con el fin de difundir experiencias locales en el mundoglobal. En ese sentido, nos hemos propuesto hacer uso intensivo de la Internet como espacio para la comunicación con autores, árbitros y lectores.En Enl@ce nos hemos empeñado en que los textos publicados sean desiguales, unos más analíticos que otros, pero en conjunto analizan una variada diversidad de fenómenos que ocurren en la sociedad; siempre relacionados, eso sí, con la información, la tecnología y el conocimiento.Durante este año 2007, hemos publicado un total de 17 trabajos de alta factura investigativa que justifican el reconocimiento que el FONACIT (Fondo Nacional de Ciencia, Tecnología e Investigaciónde Venezuela nos hiciera en el proceso de evaluación a las que se sometieron las revistas científicas venezolanas. Como resultado, el FONACIT nos ha financiado la presencia en la plataformaSCIELO (Scientific Electronic Library Online, una biblioteca digital que abarca las revistas científicasen las diferentes áreas del conocimiento. A partir de ahora, la revista tendrá una presencia sistemática y formal en el espacio digital. Así que, además de pertenecer al Registro Nacional de PublicacionesPeriódicas, Enl@ce tendrá mayor visibilidad en el mundo formal científico y académico. Sin embargo, es un hecho cierto que los trabajos publicados en ella ya han venido apareciendo en diversos sitios electrónicos. Se impone pues que hagamos un merecido reconocimiento a esos sitios (blogs personales y grupos especializados que abundan en la red, por referir no sólo los trabajos, sino por divulgar los anuncios académicos, referencias, normas de publicación, noticias de llamados a ediciones especiales y otras informaciones que son de interés general. Un mecanismo espontáneo surgido en la red, que valoramos altamente.Adicionalmente, una diversidad de sitios públicos ponen a la disposición de los lectores, en toda su extensión, los trabajos

  19. Biomarcadores moleculares en la medicina moderna

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    Elso Manuel Cruz Cruz

    2014-08-01

    Full Text Available La medicina del siglo XXI se caracteriza por el enfoque molecular, tanto en el diagnóstico, como en el tratamiento. En este sentido, abundan en la literatura científica los trabajos relacionados con el empleo de biomarcadores o marcadores biológicos. El término biomarcador se utiliza para medir una interacción entre un sistema biológico y un agente de tipo químico, físico o biológico, evaluando así una respuesta funcional o fisiológica, a nivel celular o molecular, asociada con la probabilidad del desarrollo de una enfermedad. Los biomarcadores pueden diferenciarse en tres tipos: biomarcadores de exposición, los que evalúan en un organismo la presencia de sustancias exógenas, metabolitos o el producto de la interacción entre el agente xenobiótico (compuestos naturales o sintéticos del ambiente que el organismo metaboliza y acumula y una molécula o célula diana; biomarcadores de efecto, que evalúan la alteración bioquímica, fisiológica o de comportamiento producida en el organismo y que puede ser asociada con una enfermedad; biomarcadores de susceptibilidad, indicador de la capacidad heredada o adquirida de un organismo para responder a la exposición a una sustancia xenobiótica. (1 En el campo de la salud humana, el desarrollo, validación y uso de biomarcadores se incrementa cada día por la necesidad de conocer acerca de los efectos adversos, generados por estilos de vida y, en general, por la interacción del hombre con diferentes entornos. Muchos son los ejemplos actuales del empleo de biomarcadores en la medicina. Pueden ser usados para evaluar la presencia de cáncer y la progresión y monitoreo de los tratamientos. Técnicas físico-químicas o inmunoquímicas de alta sensibilidad han sido desarrolladas para la detección de concentraciones de carcinógenos en sangre u orina, tales como: arsénico, cadmio, cromo, níquel, benceno, bifenilos policlorados, tetracloroetileno, estireno. Otros ejemplos de biomarcadores

  20. Brennand: resonancia y universalidad de las formas Brennand: resonance and the univesality of the forms

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    G. CECILIA TORO

    2001-03-01

    created by man, who as a microcosm, which forms part of nature, recreates the macrocosm. In a culture in which man has lost connections with nature, with his fellow men and their origins, we also aim here to re-parentalize man within the nature from which he takes part. Man is presented as a fractal of the Universe, who, independently of time, space and scale, is able to recreate the same forms that are created by the Universe. This process will necessarily involve both the strength of beauty in its purest and most terrible forms. Beauty, as well as religion or purity, has in itself a redeeming power and man longs for lost paradises. When our ability to perceive beauty is heightened, we are already headed in the right direction; we are already following a path which changes us from one state of consciousness to another, we are already returning to a state of unity. We will show some differentiated forms of a platyhelminth worm, Mesocestoides corti, obtained under scanning electron microscopy, which are unbelievably similar to some forms originating from the work of a great artist, the sculptor Francisco Brennand, which are also shown here. Brennand was awarded the Gabriela Mistral Prize in 1993, the highest accolade for plastic arts in America. Brennand, like a hologram and with only one single point of reference _ The Universe _ has recreated a biological Universe of incredible inherent beauty. This work also aims to show that throughout the history of our own cultures, man justifies his strong desire and his certainty of universality, with explanations of all types: philosophical, psychological, biological, physical, mathematical, astronomical and artistic

  1. Hierarchical structure of genetic distances: Effects of matrix size, spatial distribution and correlation structure among gene frequencies

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    Flávia Melo Rodrigues

    1998-06-01

    Full Text Available Geographic structure of genetic distances among local populations within species, based on allozyme data, has usually been evaluated by estimating genetic distances clustered with hierarchical algorithms, such as the unweighted pair-group method by arithmetic averages (UPGMA. The distortion produced in the clustering process is estimated by the cophenetic correlation coefficient. This hierarchical approach, however, can fail to produce an accurate representation of genetic distances among populations in a low dimensional space, especially when continuous (clinal or reticulate patterns of variation exist. In the present study, we analyzed 50 genetic distance matrices from the literature, for animal taxa ranging from Platyhelminthes to Mammalia, in order to determine in which situations the UPGMA is useful to understand patterns of genetic variation among populations. The cophenetic correlation coefficients, derived from UPGMA based on three types of genetic distance coefficients, were correlated with other parameters of each matrix, including number of populations, loci, alleles, maximum geographic distance among populations, relative magnitude of the first eigenvalue of covariance matrix among alleles and logarithm of body size. Most cophenetic correlations were higher than 0.80, and the highest values appeared for Nei's and Rogers' genetic distances. The relationship between cophenetic correlation coefficients and the other parameters analyzed was defined by an "envelope space", forming triangles in which higher values of cophenetic correlations are found for higher values in the parameters, though low values do not necessarily correspond to high cophenetic correlations. We concluded that UPGMA is useful to describe genetic distances based on large distance matrices (both in terms of elevated number of populations or alleles, when dimensionality of the system is low (matrices with large first eigenvalues or when local populations are separated

  2. 泉州湾洛阳江口2种红树林生境大型底栖动物群落多样性比较%Comparison of benthic macrofaunal communities in two mangrove habitats of Luoyangjiang Estuary in Quanzhou Bay

    Institute of Scientific and Technical Information of China (English)

    郭涛; 蔡立哲; 卓异; 饶义勇; 李想; 陈昕餠; 傅素晶; 纪剑锋

    2014-01-01

    In order to compare the benthic macrofaunal community in two mangrove habitats,Aegiceras corniculatum and Kandelia candel,in Luoyangjiang Estuary,Quanzhou Bay,China,benthic macrofauna was investigated in 4 sea-sons from April 201 1 to January 2012.A total of 49 benthic macrofaunal species were recorded,including 15 Annel-ida,8 Mollusca,15 Arthropoda,3 Chordata,2 Hexapod,1 Cnidaria,Platyhelminthes,Nemertea,Sipuncula,Oli-gochaeta and Bivalve.Nephtys oligobranchia,Assiminea brevicula,Uca arcuata,Actinia sp.showed high density in both two habitats,Phascolosoma esculenta is a dominant species in both two habitats but with lower density.Although the mean biomass of Kandelia candel was higher than Aegiceras corniculatum,the species number,density,diversity index(H′),evenness index(J)and richness index(d)of Aegiceras corniculatum were all higher.Two-way ANOVA showed that the diversity and evenness indexes of the two benthic macrofaunal communities had significant seasonal differences,habitat differences and habitat ×season differences.Cluster analysis showed high similarity between the benthic macrofaunal communities in two mangrove habitats because of same tidal zone and similar types of sediment and sediment particle size.%为探讨泉州湾洛阳江口桐花树和秋茄2种红树林生境的大型底栖动物群落是否存在明显差异,于2011年4月至2012年1月对2种红树林生境的大型底栖动物进行了季度定量调查.结果表明:4个季度在2种红树林生境定量取样获得大型底栖动物49种,其中多毛类15种,腹足类8种,甲壳类15种,鱼类3种,昆虫2种,刺胞动物、扁形动物、纽形动物、星虫动物、寡毛类和双壳类各1种.寡鳃齿吻沙蚕(Nephtys oligobranchia)、短拟沼螺(Assiminea brevicula)、弧边招潮蟹(Uca arcua-ta)、指海葵(Actinia sp.)等在2种生境均有较高的栖息密度,可口革囊星虫(Phascolosoma esculen-ta)是2种生境的常见种