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81.
Cândido Barreto de Novais Cristiana Sbrana Orivaldo José Saggin Júnior José Oswaldo Siqueira Manuela Giovannetti 《Mycorrhiza》2013,23(4):325-331
Hyphal anastomoses which play a key role in the formation of interconnected mycorrhizal networks and in genetic exchange among compatible individuals have been studied in a limited number of species and isolates of arbuscular mycorrhizal fungi (AMF), mainly in symbiotic mycelium. In this work, the occurrence and frequency of anastomosis between hyphae of the same and different germlings were assessed in tropical isolates belonging to Acaulospora, Claroideoglomus, Gigaspora, Glomus, Rhizophagus and Scutellospora. Germlings belonging to Acaulospora, Claroideoglomus, Glomus and Rhizophagus formed perfect hyphal fusions, with frequencies ranging from 9.29?±?3.01 to 79.84?±?4.39 % within the same germling and from 14.02?±?7.36 to 91.41?±?3.92 % between different germlings. Rare fusions, occurring within the same hypha, were detected in Gigaspora species, and no anastomoses were observed in Scutellospora species. The consistent detection of nuclei in perfect fusions suggests that nuclear migration is active both within and between germlings. Present data on anastomosis formation, nuclear migration and germling viability in tropical isolates of AMF widen our knowledge on the extensive and consistent occurrence of successful hyphal fusions in this group of beneficial symbionts. The ability to anastomose and establish protoplasm flow, fundamental for the maintenance of physiological and genetic continuity, may produce important fitness consequences for the obligately biotrophic AMF. 相似文献
82.
Paula Gonçalves Viana Anna Barreto Fernandes Figueiredo Isabella Dib Ferreira Gremião Luisa Helena Monteiro de Miranda Isabela Maria da Silva Antonio Jéssica Sepulveda Boechat Ana Caroline de Sá Machado Manoel Marques Evangelista de Oliveira Sandro Antonio Pereira 《Mycopathologia》2018,183(2):471-478
Sporotrichosis occurs worldwide, and the metropolitan region of Rio de Janeiro, Brazil, is a main endemic area, with a large number of human and animal cases in the last 19 years. This mycosis is more frequently described in cats rather than in dogs. There are a limited number of oral antifungal agents for the treatment of sporotrichosis in animals. In this context, the effectiveness of terbinafine in the treatment of sporotrichosis in humans, as well as the promising results of in vitro susceptibility tests, inspired us to use this drug in the therapy of this mycosis in dogs. We reported for the first time the use of terbinafine in the treatment of two dogs with sporotrichosis caused by Sporothrix brasiliensis. Moreover, we provided an overview of therapeutic features of canine sporotrichosis cases reported since the 1960s. One of the dogs presented the fixed cutaneous form of the disease, while the other patient presented hyperemia of the nasal mucosa and respiratory signs only. Terbinafine showed high antifungal activity in vitro against the canine Sporothrix isolates. The dogs were successfully treated with terbinafine, with remission of all clinical signs initially presented. The current reports indicate that this drug can emerge as a therapeutic option for canine sporotrichosis. 相似文献
83.
Lidiane Maria da Silva-Carvalho Danilo Giovanni Narciso Pastura Jennifer Vieira Gomes Priscyanne Barreto Siqueira Mariana Borges Rodrigues Viviane Moreira de Lima Bruno Pereira Berto 《Systematic parasitology》2018,95(5):455-463
A species of Isospora Schneider, 1881 (Protozoa: Apicomplexa: Eimeriidae) considered as new to science is described and characterised molecularly from the eastern white-throated spadebill Platyrinchus mystaceus Vieillot in the Parque Nacional do Itatiaia, southeastern Brazil. Isospora lopesi n. sp. has oöcysts that are subspheroidal to ovoidal, 18–24 × 18–22 (20.6 × 19.7) µm, with smooth, bilayered wall, c.1.5 μm thick. Micropyle and oöcyst residuum are absent, but one polar granule is present. Sporocysts are ellipsoidal, 12–16 × 8–11 (14.4 × 8.6) µm. The Stieda body is flattened to half-moon-shaped and sub-Stieda body is rounded. Sporocyst residuum is present, consisting of numerous spherules of different sizes. Sporozoites are vermiform with anterior and posterior refractile bodies and nucleus. Molecular analysis was conducted at the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This new isolate exhibited similarity greater than 98% with Isospora spp. isolates from spectacled warblers Sylvia conspicillata Temminck, 1820. This is the fourth isosporoid coccidian described from New World tyrannid birds, but is the first to have a complementary molecular characterisation. 相似文献
84.
Eggs of 23 Characiformes and eight Siluriformes, belonging to nine families with diverse reproductive behaviour, were ultrastructurally analysed. The migratory species exhibited non-adhesive eggs, whereas, most of the sedentary species presented some degree of egg adhesiveness. Among the Characiformes, non-adhesive eggs showed zona radiata with pore-canals or a fibrillar net at the surface; weakly adhesive eggs presented only zona radiata with pore-canals while adhesive eggs exhibited zona radiata with apparatus like globules, filaments, villi or honeycomb-like pores depending on the systematic group. The 'jelly' coat is strongly related to the Siluriformes eggs apparently without relationship with adhesiveness. A micropylar disc was present in adhesive eggs of a few species of both Characiformes and Siluriformes. Some patterns were characteristic of the animal pole, others of the vegetal pole, and others were common to both poles. The radial ridges converging to the micropyle in Astyanax bimaculatus lacustris appear to be related to fertilization. In general, egg surface structures in the Characiformes varied according to the genus, whereas all Siluriformes showed a similar egg surface pattern, regardless of the group analysed. Multivariate analysis allowed the identification of eight clusters among the Characiformes and three among the Siluriformes showing relationships between reproductive style and egg characteristics. It is suggested that egg surface and adhesiveness may be related to reproductive patterns and to phylogenesis. 相似文献
85.
M Amparo Andrade Mar Siles-Lucas José Luis Pérez Arellano Cristina Pou Barreto Basilio Valladares Elsa Espinoza Antonio Muro 《Nitric oxide》2005,13(4):217-225
Dirofilaria immitis is a worldwide filarial nematode causing heartworm disease in dogs and cats. Several mosquito species, which are able to feed both on humans and animals, can transmit this parasite. Inflammatory progression of host tissues induced by parasites are mediated by several molecules, including nitric oxide (NO), which usually exerts deleterious effects on parasites and occasionally on the host. We analyze the in vitro effect of total D. immitis adult worm somatic antigens on na?ve rat alveolar macrophage NO production and further separation of parasite proteins to define specific D. immitis somatic molecules influencing host cell NO secretion. Additionally, we address the possible influence of Wolbachia spp. on the in vitro production of NO by macrophages. Our results demonstrate that D. immitis adult worm soluble antigens are able to specifically induce NO production from host macrophages. Furthermore, we demonstrated that this effect is due to nematode antigens rather than to defined components (LPS and metabolic molecules) derived from its endosymbiont, Wolbachia spp. In addition, we were able to isolate and identify one of the parasite specific components from the DiSo extract, denominated DiID35.3 and putatively belonging to the Immunoglobulin Superfamily Protein (ISP) group, triggering NO release from macrophages in a dose-dependent and specific manner. 相似文献
86.
Pablo?Ramon?Gualberto?Cardoso Emerson?Vasconcelos?de?Andrade Lima Mariana?Modesto?de?Andrade Lima Moacyr?Jesus?Barreto?de?Melo Rêgo Claudia?Diniz?Lopes?Marques Ivan?da?Rocha Pitta Angela?Luzia?Branco?Pinto?Duarte Maira?Galdino?da?Rocha PittaEmail author 《European cytokine network》2016,27(1):1-5
Objective and Design
Psoriasis is a common, enigmatic, and recurrent disease. The precise etiology and pathogenesis of psoriasis are still unclear. Psoriasis has been treated as an inflammatory disorder related to an underlying Th1/Th17-dominated immune response. Interleukins are involved in the development of psoriasis lesions through Th-17-associated inflammation. Th1 and Th17 cytokines are found in skin lesions and in the peripheral blood of psoriasis patients.We sought to analyze serum levels of IL-1-β, IL-8, IL-9, IL-27, IL-29, IL-35, IFN-γ, TNF and TGF-β in patients with psoriasis and healthy control volunteers.Material
Blood samples were collected from fifty-three patients with psoriasis and thirty-five healthy controls.Methods
Serum cytokines concentrations were determined using an enzyme-linked immunosorbent assay.Results
Serum IL-8, IL-9, IL-27, IL-29 and TNF levels were statistically significant in psoriasis patients. Detectable serum IL-9 levels were found in 47 patients of the 53 in the psoriasis group.Conclusions
Interleukins-8, 27, 29 and TNF levels measured in the serum of psoriasis patients were slightly elevated as compared to healthy controls in a weakly significant way. On the other hand, there were highly significant differences in IL-9 levels between the two groups.87.
88.
Maria de Fátima Silva Lopes Ana Lúcia Leitão J.J. Figueiredo Marques Manuel José Teixeira Carrondo Maria Teresa Barreto Crespo 《FEMS microbiology letters》1999,176(2):483-487
The hypothesis of a proteolytic involvement in the extracellular lipase processing of a strain of Lactobacillus plantarum was considered and tested, in vitro assays with acid proteases, cathepsin D and renin revealed that both did affect lipolytic activity positively. In vivo assays with growth in the presence of the protease inhibitors pepstatin, phenylmethylsulfonyl fluoride, transepoxysuccinyl-L-leucylamido-(4-guanidino)butane and ethylenediaminetetraacetic acid showed that ethylenediaminetetraacetic acid did affect the pattern of the proteins that possess lipolytic activity. Therefore, it is suggested that a metalloprotease is involved in the processing of the extracellular lipases of L. plantarum, although other proteases can also be important. 相似文献
89.
90.
María Angélica Pérez-Mayorga Lilian Casatti Fabrício Barreto Teresa Gabriel Lourenço Brejão 《Environmental Biology of Fishes》2017,100(12):1527-1541
Environmental and spatial variables can distinctly influence the occupancy frequency distributions in stream fish. From a metacommunity context, we tested the following hypothesis, intermediate species are governed by dispersal and niche-based processes; in contrast, satellite species are governed by niche-based processes. To test this, we separately analyzed three data sets, the entire metacommunity, the intermediate species and the satellite species, using a forward selection of explanatory variables, and a partial Redundancy Distance Analysis. The fish and 31 variables of 52 stream reaches of a Brazilian river basin in the Western Amazon were collected during the dry period of 2012. The results for all of the data set revealed two different patterns: on one side, satellite species revealed that niche and dispersal-based processes were the most important; on the other side, for intermediate species and for all of the species set, only dispersal-based processes were the most important. For the data set including all of the species and the intermediate species, the variance was explained mainly by landscape scale variables. By contrast, the variance within the satellite species set was explained by local scale variables. Management efforts for intermediate species should be taking at larger scale, but they are usually less critical for the maintenance of aquatic biodiversity; on the other hand, management efforts for satellite species should be taken at smaller scale and based on specific biological and ecological information for the focal species. 相似文献