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1.
Anina Ritterband-Rosenbaum Mark S Christensen Mette Kliim-Due Line Z Petersen Betina Rasmussen Jens B Nielsen 《BMC neurology》2011,11(1):150
Background
Children diagnosed with spastic Cerebral Palsy (CP) often show perceptual and cognitive problems, which may contribute to their functional deficit. Here we investigated if altered ability to determine whether an observed movement is performed by themselves (sense of agency) contributes to the motor deficit in children with CP. 相似文献2.
3.
Intravenous pretreatment of WAG/Rij rats with BN blood 14 days before transplantation leads to permanent survival of BN heart allografts. Pretreatment with donor blood in the reverse donor-host combination gives rise to accelerated rejection of WAG/Rij hearts. Addition of 100 mg/kg Cy to the pretreatment with donor blood in the WAG/Rij to BN model resulted in permanent graft acceptance, presumably due to the phenomenon of immunologic enhancement. This effect could be observed only if the interval between drug administration and antigen pretreatment was short. The use of Cy had a more profound and long-lasting effect on humoral than on cellular immunity. Addition of 100 mg/kg Cy to the active enhancement protocol in the "easy" BN to WAG/Rij combination produced permanent graft survival in an immunologic setting reminiscent of immunologic tolerance. The combined pretreatment with donor blood and 50 mg/kg Cy in this donor-host combination abolished the operation of immunologic enhancement, which could be induced if donor blood was given alone. 相似文献
4.
Martina Dettwiler Anina Stahel Sonka Krüger Christian Gerspach Ueli Braun Monika Engels Monika Hilbe 《BMC veterinary research》2011,7(1):1-6
Background
Interspecific recombinant viruses R1ΔgC and R2ΔgI were isolated after in vitro co-infection with BoHV-1 and BoHV-5, two closely related alphaherpesviruses that infect cattle. The genetic characterization of R1ΔgC and R2ΔgI showed that they are composed of different sections of the parental genomes. The aim of this study was the characterization of the in vivo behavior of these recombinants in the natural host.Results
Four groups of four 3-month-old calves of both genders were intranasally inoculated with either the recombinant or parental viruses. A control group of two animals was also included. Viral excretion and clinical signs were monitored after infection. Histopathological examination of the central nervous system (CNS) was performed and the establishment of latency in trigeminal ganglia was analyzed by PCR. The humoral response was also evaluated using ELISA tests. Three out of four animals from the BoHV-5 infected group excreted virus for 4-10 days. Two calves shed R1ΔgC virus for one day. In R2ΔgI and BoHV-1.2ΔgCΔgI groups, infectious virus was isolated only after two or three blind passages. None of the infected animals developed neurological signs, although those infected with BoHV-5 showed histopathological evidence of viral infection. Latent viral DNA was detected in at least one calf from each infected group. Serum and/or mucosal antibodies were detected in all groups.Conclusion
Both BoHV-1/-5 recombinants and the BoHV-1 parental strain are attenuated in calves, although they are able to replicate in animals at low rates and to establish latent infections. 相似文献5.
An enduring question in cognitive neuroscience is how the physical properties of the world are represented in the brain to yield conscious perception. In most people, a particular physical stimulus gives rise to a unitary, unimodal perceptual experience. So, light energy leads to the sensation of seeing, whereas sound waves produce the experience of hearing. However, for individuals with the rare phenomenon of synaesthesia, specific physical stimuli consistently induce more than one perceptual experience. For example, hearing particular sounds might induce vivid experiences of colour, taste or odour, as might the sight of visual symbols, such as letters or digits. Here we review the latest findings on synaesthesia, and consider its possible genetic, neural and cognitive bases. We also propose a neurocognitive framework for understanding such anomalous perceptual experiences. 相似文献
6.
Background
Estimates of prevalence of wheeze depend on questionnaires. However, wording of questions may vary between studies. We investigated effects of alternative wording on estimates of prevalence and severity of wheeze, and associations with risk factors.Methods
White and South Asian children from a population-based cohort (UK) were randomly assigned to two groups and followed up at one, four and six years (1998, 2001, 2003). Parents were asked either if their child ever had “attacks of wheeze” (attack group, N=535), or “wheezing or whistling in the chest” (whistling group, N=2859). All other study aspects were identical, including questions about other respiratory symptoms.Results
Prevalence of wheeze ever was lower in the attack group than in the whistling group for all surveys (32 vs. 40% in white children aged one year, p<0.001). Prevalence of other respiratory symptoms did not differ between groups. Wheeze tended to be more severe in the attack group. The strength of association with risk factors was comparable in the two groups.Conclusions
The wording of questions on wheeze can affect estimates of prevalence, but has less impact on measured associations with risk factors. Question wording is a potential source of between-study-heterogeneity in meta-analyses. 相似文献7.
8.
Bird-pollinated plants typically have reddish flowers, but it is not clear whether this trait can be attributed to selection by birds. Here we experimentally test for the first time the foraging behaviour of sunbirds in relation to flower colour, using the Orange-breasted Sunbird Anthobaphes violacea (Nectariniidae) and the colour dimorphic Erica perspicua (Ericaceae). Pink and white flower morphotypes co-flower in intermixed populations and have similar nectar volumes and concentrations. Using floral arrays in a field aviary, we found that sunbirds preferred pink flowers; 95 % of their first choices were to pink inflorescences and they visited and probed more pink inflorescences and flowers, respectively. We also tested for flower constancy (the tendency to move between same colour rather than different colour morphotypes), but found no evidence for this in the sequence of their foraging choices, indicating that this mechanism did not maintain flower colour differences in sympatry. There was evidence for optimal foraging: 80 % of moves were to adjacent inflorescences. Unexpectedly, the preference for pink flowers observed in the aviary did not translate into a female fitness advantage for this morphotype in the field, since no difference is found in natural pollination rate, fruit or seed set. This may be because the minimization of flight distances between plants is the primary factor in sunbird foraging choices, overriding their colour preference. Antagonistic nectar robbers did not act as a selective force on the polymorphism, since nectar-robbing rates were equal between white and pink morphotypes in the field. 相似文献
9.
Anina B. J. Stahel Rhea Baggenstos Monika Engels Martina Friess Mathias Ackermann 《PloS one》2013,8(12)
The ongoing global spread of “exotic” farm animals, such as water buffaloes, which carry their native sets of viruses, may bear unknown risks for the animals, into whose ecological niches the former are introduced and vice versa. Here, we report on the occurrence of malignant catarrhal fever (MCF) on Swiss farms, where “exotic” water buffaloes were kept together with “native” animals, i.e. cattle, sheep, and goats. In the first farm with 56 water buffaloes, eight cases of MCF due to ovine herpesvirus-2 (OvHV-2) were noted, whereas additional ten water buffaloes were subclinically infected with either OvHV-2 or caprine herpesvirus-2 (CpHV-2). On the second farm, 13 water buffaloes were infected with CpHV-2 and two of those succumbed to MCF. In neither farm, any of the two viruses were detected in cattle, but the Macaviruses were present at high prevalence among their original host species, sheep and goats, respectively. On the third farm, sheep were kept well separated from water buffaloes and OvHV-2 was not transmitted to the buffaloes, despite of high prevalence of the virus among the sheep. Macavirus DNA was frequently detected in the nasal secretions of virus-positive animals and in one instance OvHV-2 was transmitted vertically to an unborn water buffalo calf. Thus, water buffaloes seem to be more susceptible than cattle to infection with either Macavirus; however, MCF did not develop as frequently. Therefore, water buffaloes seem to represent an interesting intermediate-type host for Macaviruses. Consequently, water buffaloes in their native, tropic environments may be vulnerable and endangered to viruses that originate from seemingly healthy, imported sheep and goats. 相似文献
10.
A survey was conducted todetermine the present status of five biocontrolagents established on Lantana camara L.(Verbenaceae) in South Africa. Three ofthe five agents, Calycomyza lantanae(Frick), Ophiomyia lantanae Froggatt andTeleonemia scrupulosa Stål areestablished throughout the range of L.camara. The two hispine beetles, Octotomascabripennis Guérin-Ménevilleand Uroplata girardi Pic are restrictedto the warm, subtropical regions in the easternrange of the weed, and are unable to cope withthe plants becoming seasonally leafless in dryand temperate areas. The two beetles and T. scrupulosa are rated as the most damagingagents on L. camara. The impact of O. lantanae is uncertain, and due to lowpopulations, the impact of C. lantanae isnegligible. Insect populations typicallyaccumulate to maximise their impact on plantsby midsummer, giving plants the opportunity tocompensate for the cumulative agent damageaccrued at the end of the previous growingseason. A number of parasitoids were rearedfrom U. girardi, O. lantanae andC. lantanae, but only those adapted toC. lantanae are expected to significantlyreduce its field density. The agents feed anddevelop on a wide range of lantana varieties,and where two or more varieties co-exist,insects occurred in equal abundance on thedifferent varieties. The importance of varietalpreferences appears to have beenover-estimated, but needs consideration whennew candidates are evaluated. The impact ofthese biocontrol agents is insufficient toreduce L. camara to a manageablesituation, and additional candidates arenecessary to control this weed in South Africa. 相似文献