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121.
Highly conserved protective epitopes on influenza B viruses 总被引:1,自引:0,他引:1
C Dreyfus NS Laursen T Kwaks D Zuijdgeest R Khayat DC Ekiert JH Lee Z Metlagel MV Bujny M Jongeneelen R van der Vlugt M Lamrani HJ Korse E Geelen Ö Sahin M Sieuwerts JP Brakenhoff R Vogels OT Li LL Poon M Peiris W Koudstaal AB Ward IA Wilson J Goudsmit RH Friesen 《Science (New York, N.Y.)》2012,337(6100):1343-1348
Identification of broadly neutralizing antibodies against influenza A viruses has raised hopes for the development of monoclonal antibody-based immunotherapy and "universal" vaccines for influenza. However, a substantial part of the annual flu burden is caused by two cocirculating, antigenically distinct lineages of influenza B viruses. Here, we report human monoclonal antibodies, CR8033, CR8071, and CR9114, that protect mice against lethal challenge from both lineages. Antibodies CR8033 and CR8071 recognize distinct conserved epitopes in the head region of the influenza B hemagglutinin (HA), whereas CR9114 binds a conserved epitope in the HA stem and protects against lethal challenge with influenza A and B viruses. These antibodies may inform on development of monoclonal antibody-based treatments and a universal flu vaccine for all influenza A and B viruses. 相似文献
122.
Nicolas Faysse Mostafa Errahj Catherine Dumora Hassan Kemmoun Marcel Kuper 《Agriculture and Human Values》2012,29(3):413-426
Rural development policies are often inspired by narratives that are difficult to challenge because they are based on an apparently obvious and coherent reading of reality. Research may confront such narratives and trigger debates outside the academic community, but this can have a feedback effect and lead to a simplistic or biased posture in research. This article analyzes a research-based initiative that questioned a commonly held narrative in large-scale irrigation schemes in Morocco concerning the structural weaknesses of farmer-led collective action. This initiative conceived an alternative narrative of farmer-led collective action, based on research and actions undertaken in collaboration with the farmers. The article assesses to what extent it was possible to design this narrative and to draw on it to orient research activities, actions with farmers and public engagement, without impairing the quality of the research process. The alternative narrative was designed and diffused based on three intertwined activities: (1) the identification and analysis of farmer-led collective actions, (2) the diffusion of information on successful farmer-led collective actions especially through the production of videos, and (3) exchanges with and between local farmers’ organizations. The alternative narrative that resulted from these activities emphasizes the potentialities of farmer-led collective action, and more broadly, the willingness and capabilities of many family farmers to play an active role in the governance of rural areas. The message of the alternative narrative and the distinction made between the research articles and videos in both their content and role ensured that research did not fall into simplistic or biased analyses. The alternative narrative also became a key to renewed relations between farmers and researchers and helped design training for students that pay more attention to local dynamics. In a situation in which scheme-level organizations show limited interest in reflexive enquiry, this initiative proposes some stepping stones to make it possible for changing narratives to accompany changing relations between actors. 相似文献
123.
Hijazin M Ulbegi-Mohyla H Alber J Lämmler C Hassan AA Timke M Kostrzewa M Prenger-Berninghoff E Weiss R Zschöck M 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(1-2):32-37
In the present study A. (T.) abortisuis isolated from pigs and bovines could be reliably identified by determination of phenotypic properties, genotypically by polymerase chain reaction with the help of A. (T.) abortisuis 16s-23S rDNA intergenic spacer region specific oligonucleotide primer and by Matrix-Assisted Laser Desorption Ionization-Time Of Flight mass spectrometry (MALDI-TOF MS). The latter appeared to be a promising tool for fast and cost effective identification of this species and might help to elucidate the role A. (T.) abortisuis plays in infections of pigs, bovines, possibly other animals or humans. 相似文献
124.
125.
Okab AB Ayoub MA Samara EM Abdoun KA Al-Haidary AA Koriem AA Hassan AA 《Tropical animal health and production》2012,44(7):1623-1629
Twenty-five intact Barki lambs with mean body weight of 24.81 ± 0.16?kg were used to investigate the effect of including in the diet sugar beet pulp (SBP) treated biologically with Trichoderma reesei or chemically with urea 4 % on nutrients digestibility, growth performance, nitrogen (N) utilization, and hematological and biochemical parameters. Two experiments were conducted. In the growth experiment, five lambs were randomly assigned to one of five dietary treatments. Lambs were offered isonitrogenous and isoenergetic concentrate feed mixture containing on dry matter basis 0 % SBP (D0), 50 % SBP (D1), 50 % SBP treated with 4 % urea (D2), 50 % SBP treated with T. reesei (D3), and 25 % SPB treated with 4 % urea plus 25 % SPB treated with T. reesei (D4). In the metabolism experiment, five rams were used in a 5?×?5 Latin square design and housed in metabolism crates for 21?days. The present study showed that inclusion of SBP at the level of 50 % (D1) negatively affected diet digestibility coefficients of crude protein, crude fiber, and ether extract, in addition to average daily gain, feed conversion, and N utilization. However, treatment of SBP with urea (D2), T. reesei (D3), or the combination (D4) of both had improved (P?0.05) these parameters with superiority of D3. Despite the significant differences in the tested hematological and biochemical parameters of lambs fed on biologically or chemically treated SBP diets, their levels remained within the physiological ranges which could indicate that treated SBP did not have any adverse effect on lambs' health. 相似文献
126.
Enteropathogenic Escherichia coli (EPEC) bacteria frequently cause severe enteric diseases primarily in children and in young rabbits. Their pathogenicity for pigs has been tested by oral infection of colostrum-deprived newborn, and of severely immunosuppressed weaned pigs, but colonisation of conventional weaned pigs by porcine EPEC has not been experimentally studied. EPEC show similarities to enterohaemorrhagic E. coli (EHEC) additionally carrying shiga toxin genes integrated into the chromosome by lambdoid phages. We have demonstrated earlier that the porcine EPEC prototype strain P86-1390 (O45) could be transduced in vivo (in ligated loops of weaned pigs), by Stx2 phage derived from a human EHEC. Thus, the ability of this porcine EPEC strain to colonise conventional weaned pigs under farming conditions became a question of relevance to human health. To clarify this question, four intragastric infection experiments were performed on a total of 95 conventional weaned pigs. The EPEC P86-1390 and other well-characterised porcine EPEC strains were applied to 54 pigs, leaving 41 weaned pigs as negative controls. In three experiments moderate predispositions were applied: coinfections with enterotoxigenic E. coli (ETEC) or with low-virulence TGE coronavirus, application of fumonisin B1 with a normal therapeutic dose of dexamethasone, and the increase of soybean protein concentration in the feed. A total of 41 weaned pigs served as negative controls inoculated with a commensal porcine E. coli. Housing conditions simulated the farm environment. As an overall result, ileal segments of 18.5% of infected pigs were shown to be colonised by EPEC, while no EPEC were detected in the ilea of controls. Among predisposing factors occurring on farms, feed protein content increased by 20% (26.3% crude protein, provided by 48% soybean meal) seemed to enhance EPEC colonisation and resulted in the mobilisation of spontaneous latent EPEC/ETEC infection. The results indicate that under normal farm conditions porcine EPEC may colonise conventional weaned pigs by inducing ileal attaching effacing (AE) lesions with reasonable frequency, without clinical signs. The results also suggest that conventional weaned pigs may represent undetected reservoirs of porcine EPEC, potentially giving rise to the emergence of new types of EHEC due to natural transduction by Stx phages. 相似文献
127.
Ghaffari MS Sabzevari A Vahedi H Golezardy H 《Journal of zoo and wildlife medicine》2012,43(2):229-232
The purpose of this study was to establish normal physiologic reference values for intraocular pressure (IOP) and Schirmer tear test (STT) results in clinically normal ostriches (Struthio camelus). Twenty ostriches of both sexes, 10 juveniles (1.5-2 yr of age) and 10 adults, were included in this study. Complete ophthalmic examination was performed prior to this investigation. STT was performed by inserting a standard sterile STT strip over the ventral lid margin into the ventral conjunctival sac for 60 sec. Following the STT, IOP was measured using applanation tonometry with the Tono-Pen Vet tonometer after topical instillation of one drop of 0.5% proparacaine ophthalmic solution. The mean +/- SD and range of Tono-Pen readings of IOP for all birds was 18.8 +/- 3.5, with a range of 12-24. Mean IOP in juvenile ostriches was 19.7 +/- 3.6. Mean IOP in adult ostriches was 16.9 +/- 2.9. There was no statistically significant difference between young and adult birds (P = 0.07). The mean STT values in the present study were 16.3 +/- 2.5 mm/1 min when measurements from both eyes were averaged. Mean STT in juvenile and adult ostriches was 15.4 +/- 1.8 and 17.2 +/- 2.9 mm/1 min, respectively. There was no statistically significant difference between young and adult birds (P = 0.11). No statistically significant differences between genders were found for any of the results (P > or = 0.41). In conclusion, this study provides normal reference range values for STT and IOP in clinically healthy ostriches. 相似文献
128.
Worthing KA Wigney DI Dhand NK Fawcett A McDonagh P Malik R Norris JM 《Journal of Feline Medicine and Surgery》2012,14(6):405-412
The objective of this study was to determine whether patient signalment (age, breed, sex and neuter status) is associated with naturally-occurring feline infectious peritonitis (FIP) in cats in Australia. A retrospective comparison of the signalment between cats with confirmed FIP and the general cat population was designed. The patient signalment of 382 FIP confirmed cases were compared with the Companion Animal Register of NSW and the general cat population of Sydney. Younger cats were significantly over-represented among FIP cases. Domestic crossbred, Persian and Himalayan cats were significantly under-represented in the FIP cohort, while several breeds were over-represented, including British Shorthair, Devon Rex and Abyssinian. A significantly higher proportion of male cats had FIP compared with female cats. This study provides further evidence that FIP is a disease primarily of young cats and that significant breed and sex predilections exist in Australia. This opens further avenues to investigate the role of genetic factors in FIP. 相似文献
129.
A seven-year-old castrated British shorthair cross cat was presented for coughing of five-weeks duration. Thoracic radiographs and an unguided bronchoalveolar lavage showed changes consistent with inflammatory airway disease. In addition, a soft tissue density was evident in the thoracic films between the heart and the diaphragm. Exploratory thoracotomy demonstrated a diaphragmatic hernia, probably congenital in origin, with incarceration of a portion of the hepatic parenchyma. The herniated portion of liver was resected surgically and the defect in the diaphragm closed. The cat was given a 10-day course of doxycycline post-operatively and the cough did not recur subsequently. In retrospect, the hernia was potentially an incidental problem, the cat's coughing being attributable to inflammatory airway disease. 相似文献
130.