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981.
Adenovirus infection has emerged as a serious threat to the health of captive snakes and lizards (i.e., squamates), but we know relatively little about this virus'' range of possible hosts, pathogenicity, modes of transmission, and sources from nature. We report the first case of adenovirus infection in the Iguanidae, a diverse family of lizards that is widely-studied and popular in captivity. We report adenovirus infections from two closely-related species of Anolis lizards (anoles) that were recently imported from wild populations in the Dominican Republic to a laboratory colony in the United States. We investigate the evolution of adenoviruses in anoles and other squamates using phylogenetic analyses of adenovirus polymerase gene sequences sampled from Anolis and a range of other vertebrate taxa. These phylogenetic analyses reveal that (1) the sequences detected from each species of Anolis are novel, and (2) adenoviruses are not necessarily host-specific and do not always follow a co-speciation model under which host and virus phylogenies are perfectly concordant. Together with the fact that the Anolis adenovirus sequences reported in our study were detected in animals that became ill and subsequently died shortly after importation while exhibiting clinical signs consistent with acute adenovirus infection, our discoveries suggest the need for renewed attention to biosecurity measures intended to prevent the spread of adenovirus both within and among species of snakes and lizards housed in captivity. 相似文献
982.
983.
Hayley A. Hutchings Annette Evans Peter Barnes Joanne Demmler Martin Heaven Melanie A. Hyatt Michelle James-Ellison Ronan A. Lyons Alison Maddocks Shantini Paranjothy Sarah E. Rodgers Frank Dunstan 《PloS one》2013,8(8)
Frequent mobility has been linked to poorer educational attainment. We investigated the association between moving home and moving school frequently and the early childhood formal educational achievement. We carried out a cohort analysis of 121,422 children with anonymised linked records. Our exposure measures were: 1) the number of residential moves registered with a health care provider, and 2) number of school moves. Our outcome was the formal educational assessment at age 6–7. Binary regression modeling was used to examine residential moves within the three time periods: 0 – <1 year; 1 – <4 years and 4 – <6 years. School moves were examined from age 4 to age 6. We adjusted for demographics, residential moves at different times, school moves and birth related variables. Children who moved home frequently were more likely not to achieve in formal assessments compared with children not moving. Adjusted odds ratios were significant for 3 or more moves within the time period 1 –<4 years and for any number of residential moves within the time period 4–<6 years. There was a dose response relationship, with increased odds ratios with increased frequency of residential moves (2 or more moves at 4–<6 years, adjusted odds ratio 1.16 (1.03, 1.29). The most marked effect was seen with frequent school moves where 2 or more moves resulted in an adjusted odds ratio of 2.33 (1.82, 2.98). This is the first study to examine the relationship between residential and school moves in early childhood and the effect on educational attainment. Children experiencing frequent mobility may be disadvantaged and should be closely monitored. Additional educational support services should be afforded to children, particularly those who frequently change school, in order to help them achieve the expected educational standards. 相似文献
984.
985.
Guanosine 3',5'-monophosphate (cyclic GMP) was found in the accessory gland of reproductively mature male house crickets (Acheta domesticus (L.)) up to the exceptionally high level of 500 pmol/mg protein (10(-4) mol/kg wet weight). The identity of cricket cyclic GMP was confirmed by enzymatic and spectral analysis. A survey of 10 closely related species of Orthoptera indicated that high levels of cyclic GMP in the accessory gland occur in the subfamily Gryllinae, to which A. domesticus belongs. In these crickets, cyclic GMP in the accessory gland increases together with protein content during two weeks after the final molt. Levels are not augmented by dissection, and are independent of the presence of sperm in the seminal vesicles and of the production of spermatophores by the gland. The function of cyclic GMP in the accessory gland is not yet understood. 相似文献
986.
987.
Comparison of populations of human faecal bacteria before and after in vitro incubation with plant cell wall substrates 总被引:1,自引:1,他引:0
Annette P. Slade G. M. Wyatt Catherine E. Bayliss W. M. Waites 《Journal of applied microbiology》1987,62(3):231-240
Human faecal slurries were incubated anaerobically with larchwood xylan, oat spelt xylan, wheat bran, apple cell walls or sugar beet pulp as sole carbon sources. The populations which developed during incubation were different from the inoculum, the most marked changes being an increase in the number of Bacteroides species and a decrease in the number of Fusobacterium species for all carbon sources tested. With a water-soluble preparation of larchwood xylan the population was dominated by species able to ferment this substrate, in contrast to the population which developed with the insoluble substrates. The ability to use one plant cell wall substrate appeared to be related to the ability to use others. Strains capable of using plant cell wall substrates included Bacteroides spp., Clostridium clostridiiforme, Bifidobacterium longum, Fusobacterium spp. and Escherichia coli. When incubation with two contrasting substrates (bran and larchwood xylan) was replicated, the populations which developed were reproducibly different from the inoculum and from each other. 相似文献
988.
Increasing the initial temperature of the rice fermentation of Aspergillus parasiticus NRRL 2999 from 15 to 21 C after 24 h of incubation and then to 28 C after 48 h resulted in about a fourfold increase in total aflatoxin over the usual fermentation which is held constant at 28 C for 6 days. The percentage of aflatoxin B(1), the most toxic component, in the total aflatoxin was also increased. 相似文献
989.
Warren Caldwell Opal A. McInnis Robyn J. McQuaid Gele Liu John D. Stead Hymie Anisman Shawn Hayley 《PloS one》2013,8(6)
Disturbances of brain derived neurotrophic factor (BDNF) signalling have been implicated in the evolution of depression, which likely arises, in part, as a result of diminished synaptic plasticity. Predictably, given stressor involvement in depression, BDNF is affected by recent stressors as well as stressors such as neglect experienced in early life. The effects of early life maltreatment in altering BDNF signalling may be particularly apparent among those individuals with specific BDNF polymorphisms. We examined whether polymorphisms of the Val66Met genotype might be influential in moderating how early-life events play out with respect to later coping styles, cognitive flexibility and depressive features. Among male and female undergraduate students (N = 124), childhood neglect was highly related to subsequent depressive symptoms. This outcome was moderated by the BDNF polymorphism in the sense that depressive symptoms appeared higher in Met carriers who reported low levels of neglect than in those with the Val/Val allele. However, under conditions of high neglect depressive symptoms only increased in the Val/Val individuals. In effect, the Met polymorphism was associated with depressive features, but did not interact with early life neglect in predicting later depressive features. It was further observed that among the Val/Val individuals, the relationship between neglect and depression was mediated by emotion-focused styles and diminished perceived control, whereas this mediation was not apparent in Met carriers. In contrast to the more typical view regarding this polymorphism, the data are consistent with the perspective that in the presence of synaptic plasticity presumably associated with the Val/Val genotype, neglect allows for the emergence of specific appraisal and coping styles, which are tied to depression. In the case of the reduced degree of neuroplasticity expected in the Met carriers, early life adverse experiences are not tied to coping styles, and hence less likely to be translated into depressive states. 相似文献
990.
Soil invertebrate communities are fundamental components of wet meadow ecosystems. We compared soil invertebrate biodiversity between restored and native wet meadows to assess the effectiveness of restoration practices. Biodiversity and biomass were measured in 2002 and 2003 from four native and three restored sites located along a 100-km stretch of the Platte River in south-central Nebraska. The sites ranged in age from 3 to 6 years since restoration. Samples were collected during May, July, and September each year. Soil temperature, soil moisture, percent litter cover, and root mass were measured at each site. Twelve 20 × 20 × 25–cm soil blocks were extracted at each site; soil was washed through a 1-mm sieve; and invertebrates were identified, counted, and weighed. Native sites had higher Shannon and Simpson diversity values and contained greater invertebrate biomass than restored sites. Five invertebrate taxa (isopods, scarab beetles, click beetles, earthworms, and ants) were collected with enough frequency to assess restoration effects on their occurrence. Of these, only ants occurred more frequently in restored sites. Restored sites generally had less litter cover, lower root mass, lower soil moisture, and higher soil temperature than native sites. Current restoration practices may not be completely effective at returning sites to native conditions. Physical reconstruction of wet meadow topography and high-diversity reseeding may not be adequate to fully restore soil invertebrate communities, even over extended periods of time. 相似文献