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991.
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994.
Lucas Sánchez-Sampedro Carmen Elena Gómez Ernesto Mejías-Pérez Eva Pérez-Jiménez Juan Carlos Oliveros Mariano Esteban 《Journal of virology》2013,87(12):6955-6974
Replication-competent poxvirus vectors with an attenuation phenotype and with a high immunogenic capacity of the foreign expressed antigen are being pursued as novel vaccine vectors against different pathogens. In this investigation, we have examined the replication and immunogenic characteristics of two vaccinia virus (VACV) mutants, M65 and M101. These mutants were generated after 65 and 101 serial passages of persistently infected Friend erythroleukemia (FEL) cells. In cultured cells of different origins, the mutants are replication competent and have growth kinetics similar to or slightly reduced in comparison with those of the parental Western Reserve (WR) virus strain. In normal and immune-suppressed infected mice, the mutants showed different levels of attenuation and pathogenicity in comparison with WR and modified vaccinia Ankara (MVA) strains. Wide genome analysis after deep sequencing revealed selected genomic deletions and mutations in a number of viral open reading frames (ORFs). Mice immunized in a DNA prime/mutant boost regimen with viral vectors expressing the LACK (Leishmania homologue for receptors of activated C kinase) antigen of Leishmania infantum showed protection or a delay in the onset of cutaneous leishmaniasis. Protection was similar to that triggered by MVA-LACK. In immunized mice, both polyfunctional CD4+ and CD8+ T cells with an effector memory phenotype were activated by the two mutants, but the DNA-LACK/M65-LACK protocol preferentially induced CD4+ whereas DNA-LACK/M101-LACK preferentially induced CD8+ T cell responses. Altogether, our findings showed the adaptive changes of the WR genome during long-term virus-host cell interaction and how the replication competency of M65 and M101 mutants confers distinct biological properties and immunogenicity in mice compared to those of the MVA strain. These mutants could have applicability for understanding VACV biology and as potential vaccine vectors against pathogens and tumors. 相似文献
995.
Alexandre Alberto Tonin Aleksandro Schafer da Silva Maria Luiza Thorstenberg Lívia Gelain Castilhos Raqueli Teresinha Fran?a Daniela Bitencourt Rosa Leal Marta Maria Medeiros Frescura Duarte Fernanda Silveira Flores Vogel Mario Luiz de La Rue Sonia Terezinha dos Anjos Lopes 《The Korean journal of parasitology》2013,51(4):421-426
Several studies have shown the mechanisms and importance of immune responses against Toxoplasma gondii infection and the notable role of cholinesterases in inflammatory reactions. However, the association between those factors has not yet been investigated. Therefore, the aim of this study was to evaluate the acetylcholinesterase (AChE) activity in blood and lymphocytes and the activity of butyrylcholinesterase (BChE) in serum of rats experimentally infected with T. gondii during the acute phase of infection. For that, an in vivo study was performed with evaluations of AChE and BChE activities on days 5 and 10 post-infection (PI). The activity of AChE in blood was increased on day 5 PI, while in lymphocytes its activity was enhanced on days 5 and 10 PI (P<0.05). No significant difference was observed between groups regarding to the activity of BChE in serum. A positive (P<0.01) correlation was observed between AChE activity and number of lymphocytes. The role of AChE as an inflammatory marker is well known in different pathologies; thus, our results lead to the hypothesis that AChE has an important role in modulation of early immune responses against T. gondii infection. 相似文献
996.
Carlos M. Herrera Pilar Bazaga 《Botanical journal of the Linnean Society. Linnean Society of London》2013,171(3):441-452
Phenotypic plasticity is central to the persistence of populations and a key element in the evolution of species and ecological interactions, but its mechanistic basis is poorly understood. This article examines the hypothesis that epigenetic variation caused by changes in DNA methylation are related to phenotypic plasticity in a heterophyllous tree producing two contrasting leaf types. The relationship between mammalian browsing and the production of prickly leaves was studied in a population of Ilex aquifolium (Aquifoliaceae). DNA methylation profiles of contiguous prickly and nonprickly leaves on heterophyllous branchlets were compared using a methylation‐sensitive amplified polymorphism (MSAP) method. Browsing and the production of prickly leaves were correlated across trees. Within heterophyllous branchlets, pairs of contiguous prickly and nonprickly leaves differed in genome‐wide DNA methylation. The mean per‐marker probability of methylation declined significantly from nonprickly to prickly leaves. Methylation differences between leaf types did not occur randomly across the genome, but affected predominantly certain specific markers. The results of this study, although correlative in nature, support the emerging three‐way link between herbivory, phenotypic plasticity and epigenetic changes in plants, and also contribute to the crystallization of the consensus that epigenetic variation can complement genetic variation as a source of phenotypic variation in natural plant populations. © 2012 The Linnean Society of London 相似文献
997.
Enrique Peñalver 《法国昆虫学会纪事》2013,49(1-2):138-147
During a palaeontological excavation of amber at the site named San Just, in the Utrillas-Escucha area of Teruel Province, northeastern Spain, a rich fauna from the Albian (Early Cretaceous) was discovered. Among it, three specimens of Thysanoptera were found that are here attributed to the new genus Hispanothrips n. gen. in the family Stenurothripidae Bagnall 1923. Phylogenetic analyses were conducted that support the resurrection of the family Stenurothripidae and its replacement for Adiheterothripidae Shumsher 1946. 相似文献
998.
Manjarivolo randrianirinai n. sp. is described from Southern Madagascar (Andohahela massif). Remarks on its ecology and morphology are added and a key to Manjarivolo species is provided as well as a complete photographic iconography of all known species. The scutellum of Aulonocnemini displays an unusual morphology, reported for the first time within Scarabaeoidea. For the first time we provide scanning electron microscope micrographs of the mouthparts of these beetles. 相似文献
999.
Species richness and endemicity in the Spanish vascular flora 总被引:1,自引:0,他引:1
Data from an updated and revised checklist of the Spanish flora is analyzed. The Spanish vascular plant flora is composed of 204 families, 1433 genera and 7071 species. Floristic data are analysed by considering three regions: mainland Spain with 5984 species, the Balearic Islands with 1521 species and Canary Islands with 2066 species. Extinct species are included in the analysis, with an extinction rate of 0.35% of the flora. A total of 1488 endemic species are recognized, which account for 21% of the Spanish flora. The rate of endemism in the Canary Islands is 25.9%, considerably higher than for the Balearic Islands (6.9%) and for mainland Spain (13.8%). A list of the 35 strict endemic genera is compiled, of which 65.7% are Canarian, and another list of 27 subendemic genera of which 48.1% are also Canarian. An estimated 12% of the Spanish flora is non‐native, with large variation between the 20.7% of the Canary flora, 10.5% of mainland Spain and 9.7% of the Balearic Islands. Finally, the composition of the Spanish flora for large groups and families is ana lysed. The data show that species richness and endemicity rates have been overestimated by previous authors, and are similar to other Mediterranean countries. It is concluded that a complete revision of the Macaronesian flora is strongly needed to obtain an accurate comparison with the flora of other areas. 相似文献
1000.
Jose Itzigsohn Carlos Dore Cabral Esther Hernandez Medina Obed Vazquez 《Ethnic and racial studies》2013,36(2):316-339
This article maps the structure for understanding the Dominican transnational field. By transnational field we refer to a web of linkages that affects the lives of Dominicans in their places of residence in every social field. We find that social boundaries of the nation do not coincide with political ones and the degree of participation in transnational exchanges varies. We suggest that the structure of the transnational social field is better understood by establishing and defining broad and narrow transnational social practices. 相似文献