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Pesquisa : B01.050.500.500.736.715.800 [Categoria DeCS]
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  1 / 7 MEDLINE  
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PMID:28085945
Autor:Fraija-Fernández N; Fernández M; Lehnert K; Raga JA; Siebert U; Aznar FJ
Endereço:Cavanilles Institute of Biodiversity and Evolutionary Biology, Science Park, University of Valencia, Paterna, Valencia, Spain.
Título:Long-Distance Travellers: Phylogeography of a Generalist Parasite, Pholeter gastrophilus, from Cetaceans.
Fonte:PLoS One; 12(1):e0170184, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:We studied the phylogeography and historical demography of the most generalist digenean from cetaceans, Pholeter gastrophilus, exploring the effects of isolation by distance, ecological barriers and hosts' dispersal ability on the population structure of this parasite. The ITS2 rDNA, and the mitochondrial COI and ND1 from 68 individual parasites were analysed. Worms were collected from seven oceanic and coastal cetacean species from the south western Atlantic (SWA), central eastern Atlantic, north eastern Atlantic (NEA), and Mediterranean Sea. Pholeter gastrophilus was considered a single lineage because reciprocal monophyly was not detected in the ML cladogram of all individuals, and sequence variability was <1% for mtDNA and 0% for ITS2. These results rule out a recent suggestion that P. gastrophilus would actually be a cryptic-species complex. The genetic cohesion of P. gastrophilus could rely on the extensive exploitation of wide-ranging and highly mobile cetaceans, with a putative secondary role, if any, of intermediate hosts. Unique haplotypes were detected in SWA and NEA, and an AMOVA revealed significant population structure associated to the genetic variation in these regions. The Equator possibly acts as a significant geographical barrier for cetacean movements, possibly limiting gene flow between northern and southern populations of P. gastrophilus. A partial Mantel tests revealed that the significant isolation of NEA populations resulted from geographic clustering. Apparently, the limited mobility of cetaceans used by P. gastrophilus as definitive hosts in this region, coupled with oceanographic barriers and a patchy distribution of potential intermediate hosts could contribute to significant ecological isolation of P. gastrophilus in NEA. Rather unexpectedly, no genetic differentiation was found in the Mediterranean samples of this parasite. Historical demographic analyses suggested a recent population expansion of P. gastrophilus in the Atlantic Ocean, perhaps linked to initial association and subsequent spreading in cetaceans.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Helminth)


  2 / 7 MEDLINE  
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PMID:27903316
Autor:Voronova AN; Chelomina GN; Besprozvannykh VV; Tkach VV
Endereço:Institute of Biology and Soil Science, Far Eastern Branch, Russian Academy of Sciences,100-letiya Street, 159, Vladivostok 690022,Russia.
Título:Genetic divergence of human pathogens Nanophyetus spp. (Trematoda: Troglotrematidae) on the opposite sides of the Pacific Rim.
Fonte:Parasitology; 144(5):601-612, 2017 Apr.
ISSN:1469-8161
País de publicação:England
Idioma:eng
Resumo:Human and animal nanophyetiasis is caused by intestinal flukes belonging to the genus Nanophyetus distributed on both North American and Eurasian coasts of Northern Pacific. In spite of the wide geographical distribution and medical and veterinary importance of these flukes, the intra-generic taxonomy of Nanophyetus spp. remains unresolved. The two most widely distributed nominal species, Nanophyetus salmincola and Nanophyetus schikhobalowi, both parasitizing humans and carnivorous mammals, were described from North America and eastern Eurasia, respectively. However, due to their high morphological similarity their interrelationships remained unclear and taxonomic status unstable. In this study, we explored genetic diversity of Nanophyetus spp. from the Southern Russian Far East in comparison with that of samples from North America based on the sequence variation of the nuclear ribosomal gene family (18S, internal transcribed spacers, ITS1-5·8S-ITS2 and 28S). High levels of genetic divergence in each rDNA region (nucleotide substitutions, indels, alterations in the secondary structures of the ITS1 and ITS2 transcripts) as well as results of phylogenetic analysis provided strong support for the status of N. salmincola and N. schikhobalowi as independent species.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Ribosomal)


  3 / 7 MEDLINE  
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PMID:26701345
Autor:Fraija-Fernández N; Fernández M; Raga JA; Aznar FJ
Endereço:Marine Zoology Unit, Cavanilles Institute of Biodiversity and Evolutionary Biology, Science Park, University of Valencia, PO Box 22085, 46071, Valencia, Spain. natalia.fraija@uv.es.
Título:Life-history trade-offs in a generalist digenean from cetaceans: the role of host specificity and environmental factors.
Fonte:Parasit Vectors; 8:659, 2015 Dec 23.
ISSN:1756-3305
País de publicação:England
Idioma:eng
Resumo:BACKGROUND: Adults and larvae of generalist parasites are exposed to diverse hosts and local environmental conditions throughout their life cycles, thus local adaptation is expected to occur through phenotypic plasticity and/or natural selection. We investigated how the combined effect of cryptic host specificity and local selective pressures could shape reproductive traits of a putative generalist parasite in the oceanic realm. METHODS: The LSU rDNA, ITS2 and the mt-COI of individuals of the digenean Pholeter gastrophilus (Kossack, 1910) Odhner, 1914 (Heterophyidae Leiper, 1909) from oceanic striped dolphins, Stenella coeruleoalba Meyen, and coastal bottlenose dolphins, Tursiops truncatus Montagu, in the western Mediterranean were used to elucidate whether worms were conspecific. Infection parameters were compared between both dolphin species. General Linear Mixed Models were used to analyse the influence of host species on four reproductive traits of P. gastrophilus: body size, maturity stage (non-gravid/gravid), egg size, and number of eggs in utero. AIC values were used to rank competing models, and p-values to assess the effect of specific predictors. RESULTS: Evidence indicated that worms collected from both dolphin species were conspecific. All worms collected were gravid and infection parameters did not differ between dolphin species. However, body size and egg size of individuals of P. gastrophilus were significantly larger in striped dolphins. The number of eggs in utero did not significantly differ between dolphin species but, for a given body size, worms in bottlenose dolphins harboured more eggs. A trade-off between egg size and egg number was found in worms from both dolphin species, with a higher slope in striped dolphins. CONCLUSIONS: Apparently, striped dolphin is a more suitable host for P. gastrophilus, but reproductive investment seems to be adapted to the habitat where the life-cycle develops. Worms from striped dolphins likely face the problem of finding intermediate hosts in the oceanic realm and apparently invest into offspring size to enhance the early survival of larvae and the potential to multiply asexually within the first intermediate host. The small-sized worms from bottlenose dolphins would be adapted to reproduce early because of higher adult mortality, generating smaller and numerous eggs in a coastal habitat where chances of transmission are presumably higher.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (DNA, Helminth); 0 (DNA, Ribosomal); 0 (DNA, Ribosomal Spacer); 0 (RNA, Ribosomal); 0 (RNA, ribosomal, 26S); EC 1.9.3.1 (Electron Transport Complex IV)


  4 / 7 MEDLINE  
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PMID:25563614
Autor:Heddergott M; Frantz AC; Jenrich J; Müller F
Endereço:Musée National d'Histoire Naturelle, Münster, 2160, Luxembourg, mike-heddergott@web.de.
Título:Dissections of fresh skulls confirm low prevalence of Troglotrema acutum (Trematoda: Troglotrematidae) in German badgers (Meles meles).
Fonte:Parasitol Res; 114(2):789-93, 2015 Feb.
ISSN:1432-1955
País de publicação:Germany
Idioma:eng
Resumo:We examined 131 European badgers Meles meles (Linnaeus, 1758) from 67 localities in central Germany for the presence of the cranial trematode Troglotrema acutum, as previous studies based on museum skulls might have underestimated the prevalence of the parasite in this host. We detected the flatworm in only three individuals that originated from the Rhoen Mountains (Thurigina and Bavaria). While the cranium of one host individual showed the lesions and the sponge-like widening of certain regions of the skullcap that are typical of a T. acutum infection, the skulls of the two remaining badgers did not show any deformations. The three badgers were infected by eight, 20, and 49 T. acutum individuals, respectively. Eggs of the trematode parasite were detected in the paranasal sinuses of two badgers. While badgers infected with T. acutum may not show any surface bone lesions, the results of the present study do not contradict the conclusion that the badger is only an accidental host of T. acutum.
Tipo de publicação: JOURNAL ARTICLE


  5 / 7 MEDLINE  
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PMID:21729381
Autor:Ribas A; Molina-Vacas G; Boadella M; Rodríguez-Teijeiro JD; Fernández-Cardo R; Arrizabalaga A
Endereço:Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, 605 63 Brno, Czech Republic. alexisribas@hotmail.com
Título:First report of Troglotrema acutum (Digenea, Troglotrematidae) in the Eurasian badger Meles meles in the Iberian Peninsula and presumptive lesions caused in the host.
Fonte:J Helminthol; 86(2):222-7, 2012 Jun.
ISSN:1475-2697
País de publicação:England
Idioma:eng
Resumo:A total of 109 badger Meles meles skulls from Catalonia (north-eastern Iberian Peninsula) were studied for helminths. The tremadode Troglotrema acutum is reported here for the first time in the Eurasian badger in the Iberian Peninsula and southern Europe. Three methodologies were used to detect this trematode: an examination for surface lesions, axial computed tomography and fresh skull dissection. The damage caused in the affected skulls is described, along with details regarding the use of computed tomography to detect hyperostosis, leakage in the sinus structure and bone surface erosion in the affected skulls.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T


  6 / 7 MEDLINE  
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PMID:10654398
Autor:Blair D; Wu B; Chang ZS; Gong X; Agatsuma T; Zhang YN; Chen SH; Lin JX; Chen MG; Waikagul J; Guevara AG; Feng Z; Davis GM
Endereço:Department of Zoology and Tropical Ecology, James Cook University, Townsville, Queensland, Australia. david.blair@jcu.edu.au
Título:A molecular perspective on the genera Paragonimus Braun, Euparagonimus Chen and Pagumogonimus Chen.
Fonte:J Helminthol; 73(4):295-9, 1999 Dec.
ISSN:0022-149X
País de publicação:England
Idioma:eng
Resumo:The status of the genera Euparagonimus Chen, 1963 and Pagumogonimus Chen, 1963 relative to Paragonimus Braun, 1899 was investigated using DNA sequences from the mitochondrial cytochrome c oxidase subunit I (CO1) gene (partial) and the nuclear ribosomal DNA second internal transcribed spacer (ITS2). In the phylogenetic trees constructed, the genus Pagumogonimus is clearly not monophyletic and therefore not a natural taxon. Indeed, the type species of Pagumogonimus, P. skrjabini from China, is very closely related to Paragonimus miyazakii from Japan. The status of Euparagonimus is less obvious. Euparagonimus cenocopiosus lies distant from other lungflukes included in the analysis. It can be placed as sister to Paragonimus in some analyses and falls within the genus in others. A recently published morphological study placed E. cenocopiosus within the genus Paragonimus and probably this is where it should remain.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Nome de substância:0 (DNA, Helminth)


  7 / 7 MEDLINE  
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PMID:9924963
Autor:Cabaret J; Bayssade-Dufour C; Tami G; Albaret JL
Endereço:Station de Pathologie Aviaire et de Parasitologie, Institut National de la Recherche Agronomique, Nouzilly, France.
Título:Identification of African Paragonimidae by multivariate analysis of the eggs.
Fonte:Acta Trop; 72(1):79-89, 1999 Jan 15.
ISSN:0001-706X
País de publicação:Netherlands
Idioma:eng
Resumo:A study of metacercariae and adult Paragonimidae revealed the existence in West-Africa of four species, of which two are largely recorded in literature (Paragonimus africanus and Paragonimus uterobilateralis), one was suspected (Paragonimnus westermani-like) and one remained unrecorded in Africa (Euparagonimus sp). Among the two last ones, P. westermani-like was probably confused with P. africanus, and Euparagonimus sp. with P. uterobilateralis. P. westermani-like adult worms differed from P. africanus by the morphology of ovary, testes and the size of the metraterm eggs. Euparagonimus could be identified by a short excretory bladder in metacercariae. The discriminant functions established on eggs measurements (average, maximum and minimum length, average, maximum and minimum width) were able to separate the isolates into four groups. The largest eggs (97 x 59 microm) belonged to P. westermani-like, the medium sized eggs were ascribed to P. africanus (91 x 49 microm) and to Euparagonimus sp. (84 x 50 microm), and the smaller eggs (69 x 42 microm) were identified as P. uterobilateralis. Three Paragonimidae were identified in Cameroon: P. westermani-like, P. africanus and Euparagonimus sp. Additionally, P. uterobilateralis, P. westermani-like, and Euparagonimus sp. were found in the Congo, Gabon, and the Ivory Coast, respectively.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T



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