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Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the "Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)", Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar.  相似文献   
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A bacteriophage for Escherichia coli 0103 was isolated during a study on E. coli diarrhoea in intensive breeding units of rabbits. The phage had an isometric head and a short tail and resembled coliphage N4 (Podoviridae). It had a very narrow host range and seemed to be specific for serogroup 0103, suggesting that it might be used for preliminary identification of E. coli strains of this serogroup instead of the usual slide agglutination. In view of its possible use as a therapeutic phage, we investigated its dissemination in rabbit organs after oral administration. The phage persisted in the spleen for at least 12 days. However, in vivo studies showed that this phage and a mixture of more virulent phages for E. coli 0103 were ineffective in preventing disease in rabbits inoculated with an enteropathogenic strain of E. coli 0103.  相似文献   
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Borna Disease (BD) is a mostly fatal disease of horses and sheep endemic in central Europe. Antibodies to Borna disease virus (BDV) have been described in sheep and other species living in BD non-endemic areas. Meaningful clinical BDV serology is hampered by difficulties in defining serological cut-offs, which require the investigation of populations from endemic areas. Here we studied BD serology in sheep from endemic and non-endemic areas of similar geography in Switzerland. Antibodies to BDV antigens were detected by ELISA and indirect immunofluorescence analysis (IFA) only in sera from 3 of 6 sheep with autopsy confirmed BD. One serum was positive by IFA but not by ELISA, while 2 sera were negative in both assays, indicating that not all diseased animals develop BDV specific antibodies. Six % of clinically healthy animals (6/106) from an endemic area and 2% from a non-endemic area (4/192) had serum antibody to either BDV p40 or p24 as detected by ELISA. None of the animals showed a cellular immune response to BDV p40. In some healthy sheep from the endemic area, serum antibody titers to BDV p24 antigen remained elevated over several months without onset of disease symptoms. Infections with either BDV or related viruses may thus occur at low frequency in sheep from non-endemic areas leading to the production of antibodies to BDV antigens. We further propose viral strain differences or environmental factor(s) may determine the clinical outcome.  相似文献   
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The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis.  相似文献   
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