1,198 research outputs found
Significant familial differences in the frequency of abortion and Toxoplasma gondii infection within a flock of Charollais sheep
A study was carried out to investigate the frequencies of abortion and congenital Toxoplasma gondii infection within 27
families (765 individuals) of a pedigree Charollais sheep flock maintained on a working farm in Worcestershire, UK, since
1992. Pedigree lambing records were analysed to establish the frequency of abortion for each family. The frequency of
congenital infection was determined for each family by PCR analysis of tissue samples taken from newborn lambs. Atotal of
155 lambs were tested for congenital T. gondii infection, which were all born during the study period 2000–2003. Significant
differences in the frequency of abortion between sheep families within this flock were observed with frequencies ranging
between 0% and 48% (P<0.01). Significantly different infection frequencies with T. gondii were also observed for different
families and ranged between 0% and 100% (P<0.01). Although the actual cause of each abortion was not verified, a highly
significant positive correlation was found to exist between the frequency of abortion and the frequency of T. gondii infection
in the same families (P<0.01). The data presented here raise further questions regarding the significance of congenital
transmission of T. gondii within sheep populations, the possible successive vertical transmission of T. gondii within families
of sheep, and the potential role of inherited genetic susceptibility to abortion with respect to T. gondii infection. This work
invites further study into the epidemiology of ovine toxoplasmosis and may have implications for sheep husbandry methods
in the future.
Key words: Toxoplasma gondii, ovine, toxoplasmosis, congenital, transmission, pedigree, sheep
High levels of congenital transmission of toxoplasma gondii in longitudinal and cross-sectional studies on sheep farms provides evidence of vertical transmission in ovine hosts
Recent research suggests that vertical transmission may play an important role in sustaining Toxoplasma gondii infection in some species. We report here that congenital transmission occurs at consistently high levels in pedigree Charollais and outbred sheep flocks sampled over a 3-year period. Overall rates of transmission per pregnancy determined by PCR based diagnosis, were consistent over time in a commercial sheep flock (69%) and in sympatric (60%) and allopatric (41%) populations of Charollais sheep. The result of this was that 53·7% of lambs were acquiring an infection prior to birth: 46·4% of live lambs and 90·0% of dead lambs (in agreement with the association made between T. gondii and abortion). No significant differences were observed between lamb sexes. Although we cannot distinguish between congenital transmission occurring due to primary infection at pregnancy or reactivation of chronic infection during pregnancy, our observations of consistently high levels of congenital transmission over successive lambings favour the latter
The prevalence of Neospora caninum and co-infection with Toxoplasma gondii by PCR analysis in naturally occurring mammal populations
Neospora caninum and Toxoplasma gondii are closely related intracellular protozoan parasites associated with bovine and ovine abortion respectively. Little is known about the extent of Neospora/Toxoplasma co-infection in naturally infected populations of animals. Using nested PCR techniques, based on primers from the Nc5 region of N. caninum and SAG1 for T. gondii, the prevalence of N. caninum and its co-infection with T. gondii were investigated in populations of Mus domesticus, Rattus norvegicus and aborted lambs (Ovis aries). A low frequency of infection with N. caninum was detected in the Mus domesticus (3%) and Rattus norvegicus (4·4%) populations. A relatively high frequency of infection with N. caninum was detected in the brains of aborted lambs (18·9%). There was no significant relationship between N. caninum and T. gondii co-infection. Investigation of the tissue distribution of Neospora, in aborted lambs, showed that Neospora could not be detected in tissues other than brain and this was in contrast to Toxoplasma where the parasite could be frequently detected in a range of tissues
Burrowing of urinary bladder wall by the tip of a size 22 Fr silicone foley catheter in an adult male patient with multiple sclerosis and suprapubic cystostomy: should caution be exercised in using a size 22 Fr silicone foley catheter for long-term drainage of neuropathic bladder?
Is translation semantically mediated? Evidence from Welsh-English bilingual aphasia
The involvement of the semantic system in picture naming is undisputed. However, it has been proposed that translation could take place via direct lexical links between L1 and L2 word forms in addition to or instead of via semantics(i.e., with translation going from a spoken word in L1 accessing its meaning and this meaning then leading to the retrieval of the translation equivalent in L2). There is conflicting evidence in the psycholinguistic literature as to the extent of semantic mediation in translation vs. picture naming tasks (Potter et al, 1984; Kroll and Stewart, 1994). More recently, Hernandez et al (2010) investigated this question in a case study of JFF, a proficient bilingual Spanish-Catalan speaker with Alzheimer’s disease and naming difficulties due to a semantic deficit. As JFF’s semantic deficit did not only affect picture naming but also translation tasks, the authors concluded against the existence of functional direct lexical links to support translation. The goal of our study was to explore this issue further in a larger sample of proficient bilingual patients with aphasia and word finding difficulties in both languages. More specifically, we compare the rate of semantic errors produced in naming vs. translation tasks
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A web-based resource for the assessment of language skills in English and Welsh-speaking adults with neurological deficits
We will present a new web-based resource for the assessment of language disorders in English monolinguals and Welsh/English bilingual adults with neurological deficits. Although both languages are typically affected in bilinguals, few valid tools are available to accurately and comprehensively assess both languages, and none in Welsh-English speakers. This impedes both accurate diagnosis and therapeutic efforts. The goal of this work was to provide a secure user-friendly platform to allow clinicians to administer and score tests on-line or offline. The battery includes 16 different tests developed to measure the same abilities in Welsh and in English and to be of comparable difficulty in the two languages. These tests assess a range of language skills: spoken word production (picture naming, naming to definition, translation, repetition), reading (reading aloud, lexical decision, paragraph reading) and written production (spelling to dictation, delayed copy, written picture description). The tests manipulate and/or control for key psycholinguistic variables (e.g., word frequency, length, concreteness, Welsh-English similarity, grammatical class, lexicality). In the on-line version, all tests are programmed to allow automatic and standardized presentation of auditory or visual stimuli. The program also records oral or written responses and response times for each stimulus, and provide summary scores broken down by stimulus category. Each test package includes: a) an introductory section explaining the test aims and rationale, b) instructions on how to administer the test, c) scoring instructions and scoring sheets and d) performance indicators (e.g., Z-score) based on control data from 120 neurologically healthy participants (40 English monolinguals and 80 Welsh-English bilinguals, broken down by age, language and educational level. The presentation will include demos of the interface and of computerized test administration and scoring. Note that this new resource is suitable for the assessment of both English monolingual and Welsh-English bilingual adults.ESRC/MRC; Bangor ESRC Impact Acceleration Accoun
Maternal neurofascin-specific autoantibodies bind to structures of the fetal nervous system during pregnancy, but have no long term effect on development in the rat
Neurofascin was recently reported as a target for axopathic autoantibodies in patients with multiple sclerosis (MS), a response that will exacerbate axonal pathology and disease severity in an animal model of multiple sclerosis. As transplacental transfer of maternal autoantibodies can permanently damage the developing nervous system we investigated whether intrauterine exposure to this neurofascin-specific response had any detrimental effect on white matter tract development. To address this question we intravenously injected pregnant rats with either a pathogenic anti-neurofascin monoclonal antibody or an appropriate isotype control on days 15 and 18 of pregnancy, respectively, to mimic the physiological concentration of maternal antibodies in the circulation of the fetus towards the end of pregnancy. Pups were monitored daily with respect to litter size, birth weight, growth and motor development. Histological studies were performed on E20 embryos and pups sacrificed on days 2, 10, 21, 32 and 45 days post partum. Results: Immunohistochemistry for light and confocal microscopy confirmed passively transferred anti-neurofascin antibody had crossed the placenta to bind to distinct structures in the developing cortex and cerebellum. However, this did not result in any significant differences in litter size, birth weight, or general physical development between litters from control mothers or those treated with the neurofascin-specific antibody. Histological analysis also failed to identify any neuronal or white matter tract abnormalities induced by the neurofascin-specific antibody. Conclusions: We show that transplacental transfer of circulating anti-neurofascin antibodies can occur and targets specific structures in the CNS of the developing fetus. However, this did not result in any pre- or post-natal abnormalities in the offspring of the treated mothers. These results assure that even if anti-neurofascin responses are detected in pregnant women with multiple sclerosis these are unlikely to have a negative effect on their children
The mass fraction of halo stars contributed by the disruption of globular clusters in the E-MOSAICS simulations
Globular clusters (GCs) have been posited, alongside dwarf galaxies, as significant contributors to the field stellar population of the Galactic halo. In order to quantify their contribution, we examine the fraction of halo stars formed in stellar clusters in the suite of 25 present-day Milky Way-mass cosmological zoom simulations from the E-MOSAICS project. We find that a median of and per cent of the mass in halo field stars formed in clusters and GCs, defined as clusters more massive than and , respectively, with the -th percentiles spanning - and - per cent being caused by differences in the assembly histories of the host galaxies. Under the extreme assumption that no stellar cluster survives to the present day, the mass fractions increase to a median of and per cent. These small fractions indicate that the disruption of GCs plays a sub-dominant role in the build-up of the stellar halo. We also determine the contributed halo mass fraction that would present signatures of light-element abundance variations considered to be unique to GCs, and find that clusters and GCs would contribute a median of and per cent, respectively. We estimate the contributed fraction of GC stars to the Milky Way halo, based on recent surveys, and find upper limits of - per cent (significantly lower than previous estimates), suggesting that models other than those invoking strong mass loss are required to describe the formation of chemically enriched stellar populations in GCs
The epidemiology of injuries across the weight-training sports
Background: Weight-training sports, including weightlifting, powerlifting, bodybuilding, strongman, Highland Games, and CrossFit, are weight-training sports that have separate divisions for males and females of a variety of ages, competitive standards, and bodyweight classes. These sports may be considered dangerous because of the heavy loads commonly used in training and competition. Objectives: Our objective was to systematically review the injury epidemiology of these weight-training sports, and, where possible, gain some insight into whether this may be affected by age, sex, competitive standard, and bodyweight class. Methods: We performed an electronic search using PubMed, SPORTDiscus, CINAHL, and Embase for injury epidemiology studies involving competitive athletes in these weight-training sports. Eligible studies included peer-reviewed journal articles only, with no limit placed on date or language of publication. We assessed the risk of bias in all studies using an adaption of the musculoskeletal injury review method. Results: Only five of the 20 eligible studies had a risk of bias score ≥75 %, meaning the risk of bias in these five studies was considered low. While 14 of the studies had sample sizes >100 participants, only four studies utilized a prospective design. Bodybuilding had the lowest injury rates (0.12–0.7 injuries per lifter per year; 0.24–1 injury per 1000 h), with strongman (4.5–6.1 injuries per 1000 h) and Highland Games (7.5 injuries per 1000 h) reporting the highest rates. The shoulder, lower back, knee, elbow, and wrist/hand were generally the most commonly injured anatomical locations; strains, tendinitis, and sprains were the most common injury type. Very few significant differences in any of the injury outcomes were observed as a function of age, sex, competitive standard, or bodyweight class. Conclusion: While the majority of the research we reviewed utilized retrospective designs, the weight-training sports appear to have relatively low rates of injury compared with common team sports. Future weight-training sport injury epidemiology research needs to be improved, particularly in terms of the use of prospective designs, diagnosis of injury, and changes in risk exposure
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