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51.
Papassotiropoulos A Stephan DA Huentelman MJ Hoerndli FJ Craig DW Pearson JV Huynh KD Brunner F Corneveaux J Osborne D Wollmer MA Aerni A Coluccia D Hänggi J Mondadori CR Buchmann A Reiman EM Caselli RJ Henke K de Quervain DJ 《Science (New York, N.Y.)》2006,314(5798):475-478
Human memory is a polygenic trait. We performed a genome-wide screen to identify memory-related gene variants. A genomic locus encoding the brain protein KIBRA was significantly associated with memory performance in three independent, cognitively normal cohorts from Switzerland and the United States. Gene expression studies showed that KIBRA was expressed in memory-related brain structures. Functional magnetic resonance imaging detected KIBRA allele-dependent differences in hippocampal activations during memory retrieval. Evidence from these experiments suggests a role for KIBRA in human memory. 相似文献
52.
Van Waeyenberghe L Pasmans F D'Herde K Ducatelle R Favoreel H Li SJ Haesebrouck F Martel A 《Veterinary research》2012,43(1):32
ABSTRACT: Although aspergillosis is one of the most common diseases in captive birds, the pathogenesis of avian aspergillosis is poorly known. We studied the role of avian respiratory macrophages as a first line of defense against avian aspergillosis. The phagocytic and killing capacities of avian respiratory macrophages were evaluated using pigeon respiratory macrophages that were inoculated with Aspergillus fumigatus conidia. On average, 25% of macrophage-associated conidia were phagocytosed after one hour. Sixteen percents of these cell-associated conidia were killed after 4 h and conidial germination was inhibited in more than 95% of the conidia. A. fumigatus conidia were shown to be cytotoxic to the macrophages. Intracellularly germinating conidia were located free in the cytoplasm of necrotic cells, as shown using transmission electron microscopy. These results suggest that avian respiratory macrophages may prevent early establishment of infection, unless the number of A. fumigatus conidia exceeds the macrophage killing capacity, leading to intracellular germination and colonization of the respiratory tract. 相似文献
53.
Abeysekara S Zello GA Lohmann KL Alcorn J Hamilton DL Naylor JM 《Canadian journal of veterinary research》2012,76(1):16-22
In a crossover study, 5 calves were made acidotic by intermittent intravenous infusion of isotonic hydrochloric acid (HCl) over approximately 24 h. This was followed by rapid (4 h) or slow (24 h) correction of blood pH with isotonic sodium bicarbonate (NaHCO(3)) to determine if rapid correction of acidemia produced paradoxical cerebrospinal fluid (CSF) acidosis. Infusion of HCl produced a marked metabolic acidosis with respiratory compensation. Venous blood pH (mean ± S(x)) was 7.362 ± 0.021 and 7.116 ± 0.032, partial pressure of carbon dioxide (Pco(2), torr) 48.8 ± 1.3 and 34.8 ± 1.4, and bicarbonate (mmol/L), 27.2 ± 1.27 and 11 ± 0.96; CSF pH was 7.344 ± 0.031 and 7.240 ± 0.039, Pco(2) 42.8 ± 2.9 and 34.5 ± 1.4, and bicarbonate 23.5 ± 0.91 and 14.2 ± 1.09 for the period before the infusion of hydrochloric acid and immediately before the start of sodium bicarbonate correction, respectively. In calves treated with rapid infusion of sodium bicarbonate, correction of venous acidemia was significantly more rapid and increases in Pco(2) and bicarbonate in CSF were also more rapid. However, there was no significant difference in CSF pH. After 4 h of correction, CSF pH was 7.238 ± 0.040 and 7.256 ± 0.050, Pco(2) 44.4 ± 2.2 and 34.2 ± 2.1, and bicarbonate 17.8 ± 1.02 and 14.6 ± 1.4 for rapid and slow correction, respectively. Under the conditions of this experiment, rapid correction of acidemia did not provoke paradoxical CSF acidosis. 相似文献
54.
Künzel F Hittmair KM Hassan J Dupré G Russold E Guija de Arespachochaga A Fuchs-Baumgartinger A Bilek A 《Journal of the American Animal Hospital Association》2012,48(2):97-104
Thymomas are rarely recorded in rabbits, and the literature includes comparatively few cases. Medical records were reviewed to identify all pet rabbits in which a mediastinal mass was diagnosed between Feb 2007 and Jan 2010. Signalment, history, clinical signs, diagnostic work-up (including laboratory data, diagnostic imaging, and ultrasound-guided fine-needle aspiration of the mediastinal mass), treatment modalities, survival time, and histologic findings were evaluated. Cytologic and/or histopathologic examinations revealed thymomas in all rabbits with mediastinal masses (n=13). Rabbits with thymomas showed clinical signs of dyspnea (76.9%), exercise intolerance (53.9%), and bilateral exophthalmos (46.2%). In seven rabbits the thymoma was removed surgically. Two rabbits were treated conservatively, and four rabbits were euthanized because of their poor clinical condition. The two rabbits that underwent surgery were euthanized 6 mo and 34 mo later. Mediastinal masses in rabbits appear to be more common than previously believed and consist primarily of thymomas rather than thymic lymphomas. Cytology of samples collected by ultrasound-guided fine-needle aspiration is an accurate diagnostic tool for the identification of thymomas in rabbits. Due to a high rate of perioperative mortality, intensive perioperative care and the provision of a low-stress environment are recommended for a successful thoracotomy. 相似文献
55.
56.
Daniela C. Hadorn Vanessa Racloz Heinzpeter Schwermer Katharina D.C. St?rk 《Veterinary research》2009,40(6)
Vector-borne diseases pose a special challenge to veterinary authorities due to complex and time-consuming surveillance programs taking into account vector habitat. Using stochastic scenario tree modelling, each possible surveillance activity of a future surveillance system can be evaluated with regard to its sensitivity and the expected cost. The overall sensitivity of various potential surveillance systems, composed of different combinations of surveillance activities, is calculated and the proposed surveillance system is optimized with respect to the considered surveillance activities, the sensitivity and the cost. The objective of this project was to use stochastic scenario tree modelling in combination with a simple cost analysis in order to develop the national surveillance system for Bluetongue in Switzerland. This surveillance system was established due to the emerging outbreak of Bluetongue virus serotype 8 (BTV-8) in Northern Europe in 2006. Based on the modelling results, it was decided to implement an improved passive clinical surveillance in cattle and sheep through campaigns in order to increase disease awareness alongside a targeted bulk milk testing strategy in 200 dairy cattle herds located in high-risk areas. The estimated median probability of detection of cases (i.e. sensitivity) of the surveillance system in this combined approach was 96.4%. The evaluation of the prospective national surveillance system predicted that passive clinical surveillance in cattle would provide the highest probability to detect BTV-8 infected animals, followed by passive clinical surveillance in sheep and bulk milk testing of 200 dairy cattle farms in high-risk areas. This approach is also applicable in other countries and to other epidemic diseases. 相似文献
57.
Dreher UM Hofmann-Lehmann R Meli ML Regula G Cagienard AY Stärk KD Doherr MG Filli F Hässig M Braun U Kocan KM Lutz H 《Veterinary microbiology》2005,107(1-2):71-79
Anaplasma marginale infection in Europe has been limited to the Mediterranean and eastern countries, to Austria and to very sporadic cases in Switzerland. There are no reports of its occurrence in the countries north of Switzerland. A severe outbreak of anaplasmosis in August 2002 in a cattle farm in the canton Grisons, Switzerland, north of the Alps, with more than 300 cattle that had to be culled, came unexpected and gave reason to hypothesize presence of an increased yet undetected prevalence of A. marginale in Switzerland. Randomly selected bovine serum samples collected in 1998 and 2003 were tested using a competitive inhibitory ELISA (cELISA) to test the hypothesis. Our validation of the diagnostic sensitivity and specificity of this test, done in the outbreak herd, yielded 99.2 and 83.3%, respectively, probably underestimating the true specificity. The true seroprevalence of anaplasmosis in Swiss cattle determined by cELISA was likely to be zero with upper 95% confidence limits of 2.49% in the canton Grisons and 1.17% in the rest of Switzerland, respectively, in 1998. For 2003, these estimates were even lower. There was no significant difference in apparent prevalences between 1998 and 2003. In search of a possible reservoir, three chamoises out of 46 free ranging wild ruminants from the Swiss National Park, Grisons, tested positive in the cELISA. This reaction is in accordance with A. marginale or a cross reacting agent such as Anaplasma ovis. From our results we conclude that the hypothesis of an increased prevalence of anaplasmosis in cattle in Switzerland must be rejected. 相似文献
58.
Hauser R Breidenbach E Thür B Griot C Engels M Stärk K 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(5-6):188-192
At the Swiss Federal Veterinary Office risk analyses are conducted according to international standards. A risk analysis contains the elements risk management, risk assessment and risk communication. A risk assessment is based on risk profile, hazard identification and a pathway model. All available information is gathered, documented and assessed and the risk estimated. The question. "What is the probability that unprocessed wild boar meat imported to Switzerland from the federal state Mecklenburg Western Pommerania is contaminated with classical swine fever virus?" was answered by a release assessment. The hazard identification recognized classical swine fever virus and attenuated live virus vaccine used for oral immunization as hazards. The probability of contamination was estimated to be small. The question: "What is the likelihood to introduce Aujeszky's disease to Switzerland and infect the indigenous pig population with the disease, by means of importing pork and meat products?" was answered by assessing the release, exposure and resulting consequences. The risk of an infection of the indigenous pig population was estimated to be very small, as 80% of the imported products derive from countries or zones free from Aujeszky's disease. Furthermore the majority of the imported products are processed. The strict implementation of the regulations governing feeding of food wastes to pigs reduces the probability of exposure. In all assessments the risk management decides on a strategy to deal with the risk, taking into consideration the results and recommendations derived from the risk assessment as well as other relevant factors. 相似文献
59.
Risk factors for infection of sow herds with porcine reproductive and respiratory syndrome (PRRS) virus 总被引:10,自引:0,他引:10
Mortensen S Stryhn H Søgaard R Boklund A Stärk KD Christensen J Willeberg P 《Preventive veterinary medicine》2002,53(1-2):83-101
In 1992, the porcine reproductive and respiratory syndrome virus (PRRSV) of European type (PRRSV-EU) was introduced in Denmark. By 1996, the virus had spread to approximately 25% of the Danish herds. In January 1996, a modified-live vaccine based on the American type of the virus (PRRSV-US) was used in replacement boars for Danish artificial insemination (AI) centres and from July 1996, the vaccine was used in PRRSV-EU infected herds for prevention of disease. Soon after vaccine introduction, PRRSV non-infected herds experienced outbreaks of disease due to infection with PRRSV-US. In this study, we investigated the risk factors (biosecurity level, animals, exposure from PRRSV-US-infected neighbour herds, semen, herd size, pig density and herd density) for infection with PRRSV-US in a cohort of 1071 sow herds; we used a nested case-control study. The retrospective observation period lasted from June 1996 (when they all were non-infected) to October 1997. Seventy-three non-vaccinated, closed sow herds became infected with the vaccine strain during this period. Each case herd was matched with two control herds from the cohort (controls had not been infected at the time of infection in the case herds). The data were analysed using a Cox-regression model. The hazard of infection increased significantly with exposure from PRRSV-US-infected neighbouring herds, purchase of animals from herds incubating PRRSV-US infection, increasing herd size and purchase of semen from boars at PRRSV-US-infected AI centres. The results are consistent with the modified-live vaccine strain spread to other herds by trade with animals and semen and by neighbour (area) transmission. We suggest that virus spread by aerosols was a frequent mode of transmission. 相似文献
60.
Surveillance for rare and emerging infectious diseases poses a special challenge to veterinary services. Most emerging infectious diseases like bovine tuberculosis (bTB) are zoonoses, affecting both human and animal populations. Despite the low prevalence of such an emerging infectious disease at time of incursion, the surveillance system should be able to detect the presence of the disease as early as possible. Because passive surveillance is a relatively cost-effective and therefore commonly used process, it is the basic tool for infectious disease surveillance. Because of under-reporting in passive surveillance, cost-intensive active surveillance is often required to increase the sensitivity of the surveillance system. Using scenario tree modelling, the sensitivity of passive and active surveillance system components (SSC) can be quantified and an optimal, cost-effective surveillance system developed considering the contributions of each SSC. We illustrate this approach with the example of bTB surveillance in Switzerland where the surveillance system for bTB consists of meat inspection at the slaughterhouse (SLI), passive clinical surveillance on farm (CLIN) and human surveillance (HS). While the sensitivities for CLIN and HS were both negligible (<1%), SLI was assessed to be 55.6%. The scenario tree model showed that SLI is increasable up to 80.4% when the disease awareness of meat inspectors in Switzerland is enhanced. A hypothetical random survey (RS) was also compared with a targeted survey (TS) in high-risk strata of the cattle population, and the sensitivity of TS was 1.17-fold better than in RS but with 50% of the sample size. 相似文献