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171.
172.
Evelyne Picard-Meyer Alexandre Servat Marine Wasniewski Matthieu Gaillard Christophe Borel Florence Cliquet 《BMC veterinary research》2017,13(1):387
Background
Rabies is a fatal viral encephalitic disease that is caused by lyssaviruses which can affect all mammals, including human and bats. In Europe, bat rabies cases are attributed to five different lyssavirus species, the majority of rabid bats being attributed to European bat 1 lyssavirus (EBLV-1), circulating mainly in serotine bats (Eptesicus serotinus). In France, rabies in bats is under surveillance since 1989, with 77 positive cases reported between 1989 and 2016.Case presentation
In the frame of the bat rabies surveillance, an unusual mortality of serotine bats was reported in 2009 in a village in North-East France. Six juvenile bats from an E. serotinus maternity colony counting ~200 individuals were found to be infected with EBLV-1. The active surveillance of the colony by capture sessions of bats from July to September 2009 showed a high detection rate of neutralising EBLV-1 antibodies (≈ 50%) in the colony. Moreover, one out of 111 animals tested was found to shed viable virus in saliva, while lyssavirus RNA was detected by RT-PCR for five individuals.Conclusion
This study demonstrated that the lyssavirus infection in the serotine maternity colony was followed by a high rate of bat rabies immunity after circulation of the virus in the colony. The ratio of seropositive bats is probably indicative of an efficient virus transmission coupled to a rapid circulation of EBLV-1 in the colony.173.
Veith M Lipscher E Oz M Kiefer A Baran I Polymeni RM Steinfartz S 《Molecular phylogenetics and evolution》2008,47(3):916-931
The urodelan genus Lyciasalamandra, which inhabits a relatively small area along the southern Turkish coast and some Aegean islands, provides an outstanding example of a diverse but phylogenetically unresolved taxon. Molecular trees contain a single basal polytomy that could be either soft or hard. We here use the information of nuclear (allozymes) and mitochondrial (fractions of the 16S rRNA and ATPase genes) datasets in combination with area relationships of lineages to resolve the phylogenetic relationships among Lyciasalamandra species in the absence of sufficient node support. We can show that neither random processes nor introgressive hybridization can be invoked to explain that the majority of pairs of sister taxa form geographically adjacent units and interpret that this pattern has been shaped by vicariant events. Topology discordance between mitochondrial and nuclear trees mainly refers to an affiliation of L. helverseni, a taxon restricted to the Karpathos archipelago, to the western-most and geographically proximate mainland taxon in the nuclear tree, while in the organelle tree it turns out to be the sister lineage to the geographically most distant eastern clade. As this discordance cannot be explained by long-branch attraction in either dataset we suppose that oversea dispersal may have accounted for a second colonization of the Karpathos archipelago. It may have initiated introgression and selection driven manifestation of alien eastern mitochondrial genomes on a western nuclear background. Our approach of testing for area relationships of sister taxa against the null hypothesis of random distribution of these taxa seems to be especially helpful in phylogenetic studies where traditional measures of phylogenetic branch support fail to reject the null hypothesis of a hard polytomy. 相似文献
174.
Sylvie Cousin Evelyne Brambilla Jun Yang Erko Stackebrandt 《International microbiology》2008,11(2):91-100
The composition of 681 aerobic and heterotrophic strains that were isolated on two different media was assessed at four sampling points along a ~300 m stretch of a karst water rivulet. Based on partial sequence analysis of 16S rRNA genes, members of 35 genera were identified; however, only a few species dominated as their representatives were repeatedly isolated at different sampling sites. Determination of the phylum affiliation showed that the isolates included members of Bacteriodetes (especially the genus Flavobacterium) and Proteobacteria (mainly Pseudomonas and Stenotrophomonas). MALDI-TOF analysis and/or similarities of partial sequences of flavobacterial strains resulted in the generation of almost complete 16S rRNA gene sequences for 100 isolates, about 60 of which may represent novel phylospecies. The number as well as the intra-phylum distribution of the isolates changed with distance from the discharge site. While phylogenetically restricted at the spring, diversity increased at downstream sampling sites. 相似文献
175.
176.
Alibaud L Köhler T Coudray A Prigent-Combaret C Bergeret E Perrin J Benghezal M Reimmann C Gauthier Y van Delden C Attree I Fauvarque MO Cosson P 《Cellular microbiology》2008,10(3):729-740
The human pathogen Pseudomonas aeruginosa has been shown previously to use similar virulence factors when infecting mammalian hosts or Dictyostelium amoebae. Here we randomly mutagenized a clinical isolate of P. aeruginosa , and identified mutants with attenuated virulence towards Dictyostelium . These mutant strains also exhibited a strong decrease in virulence when infecting Drosophila and mice, confirming that P. aeruginosa makes use of similar virulence traits to confront these very different hosts. Further characterization of these bacterial mutants showed that TrpD is important for the induction of the quorum-sensing circuit, while PchH and PchI are involved in the induction of the type III secretion system. These results demonstrate the usefulness and the relevance of the Dictyostelium host model to identify and analyse new virulence genes in P. aeruginosa . 相似文献
177.
Caroline Lacroux Stéphanie Simon Sylvie L. Benestad Séverine Maillet Jacinthe Mathey Séverine Lugan Fabien Corbière Hervé Cassard Pierrette Costes Dominique Bergonier Jean-Louis Weisbecker Torffin Moldal Hugh Simmons Frederic Lantier Cécile Feraudet-Tarisse Nathalie Morel Fran?ois Schelcher Jacques Grassi Olivier Andréoletti 《PLoS pathogens》2008,4(12)
Since prion infectivity had never been reported in milk, dairy products originating from transmissible spongiform encephalopathy (TSE)-affected ruminant flocks currently enter unrestricted into the animal and human food chain. However, a recently published study brought the first evidence of the presence of prions in mammary secretions from scrapie-affected ewes. Here we report the detection of consistent levels of infectivity in colostrum and milk from sheep incubating natural scrapie, several months prior to clinical onset. Additionally, abnormal PrP was detected, by immunohistochemistry and PET blot, in lacteal ducts and mammary acini. This PrPSc accumulation was detected only in ewes harbouring mammary ectopic lymphoid follicles that developed consequent to Maedi lentivirus infection. However, bioassay revealed that prion infectivity was present in milk and colostrum, not only from ewes with such lympho-proliferative chronic mastitis, but also from those displaying lesion-free mammary glands. In milk and colostrum, infectivity could be recovered in the cellular, cream, and casein-whey fractions. In our samples, using a Tg 338 mouse model, the highest per ml infectious titre measured was found to be equivalent to that contained in 6 µg of a posterior brain stem from a terminally scrapie-affected ewe. These findings indicate that both colostrum and milk from small ruminants incubating TSE could contribute to the animal TSE transmission process, either directly or through the presence of milk-derived material in animal feedstuffs. It also raises some concern with regard to the risk to humans of TSE exposure associated with milk products from ovine and other TSE-susceptible dairy species. 相似文献
178.
Tanaka KS Houghton TJ Kang T Dietrich E Delorme D Ferreira SS Caron L Viens F Arhin FF Sarmiento I Lehoux D Fadhil I Laquerre K Liu J Ostiguy V Poirier H Moeck G Parr TR Rafai Far A 《Bioorganic & medicinal chemistry》2008,16(20):9217-9229
Osteomyelitis is a difficult to treat bacterial infection of the bone. Delivering antibacterial agents to the bone may overcome the difficulties in treating this illness by effectively concentrating the antibiotic at the site of infection and by limiting the toxicity that may result from systemic exposure to the large doses conventionally used. Using bisphosphonates as osteophilic functional groups, different forms of fluoroquinolone esters were synthesized and evaluated for their ability to bind bone and to release the parent antibacterial agent. Bisphosphonated glycolamide fluoroquinolone esters were found to present a profile consistent with effective and rapid bone binding and efficient release of the active drug moiety. They were assessed for their ability to prevent bone infection in vivo and were found to be effective when the free fluoroquinolones were not. 相似文献
179.
Albouy G Sterpenich V Balteau E Vandewalle G Desseilles M Dang-Vu T Darsaud A Ruby P Luppi PH Degueldre C Peigneux P Luxen A Maquet P 《Neuron》2008,58(2):261-272
Functional magnetic resonance imaging (fMRI) was used to investigate the cerebral correlates of motor sequence memory consolidation. Participants were scanned while training on an implicit oculomotor sequence learning task and during a single testing session taking place 30 min, 5 hr, or 24 hr later. During training, responses observed in hippocampus and striatum were linearly related to the gain in performance observed overnight, but not over the day. Responses in both structures were significantly larger at 24 hr than at 30 min or 5 hr. Additionally, the competitive interaction observed between these structures during training became cooperative overnight. These results stress the importance of both hippocampus and striatum in procedural memory consolidation. Responses in these areas during training seem to condition the overnight memory processing that is associated with a change in their functional interactions. These results show that both structures interact during motor sequence consolidation to optimize subsequent behavior. 相似文献
180.
Anero R Díaz-Lanza A Ollivier E Baghdikian B Balansard G Bernabé M 《Phytochemistry》2008,69(3):805-811
Six monoterpene glycosides were isolated from Fadogia agrestis. Their structures were elucidated using a combination of mass spectroscopy, 1D- and 2D-homo- and hetero-NMR spectroscopy and chemical analysis, and established as being derivatives of 2,6-dimethyl-2(E),6(Z)-octadiene-1,8-diol containing from two to four units of rhamnopyranose and, three of them, one or two additional units of glucopyranose. In three of the compounds an acyl group of 8-hydroxy-2,6-dimethyl-2(E),6(Z)-octadienoyl was found esterifying the O-2 position of one of the units of rhamnopyranose. 相似文献