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1.
Intragenic Sequences Affect the Expression of the Gene Encoding Glial Fibrillary Acidic Protein 总被引:6,自引:1,他引:5
We show that the expression of the gene encoding glial fibrillary acidic protein (GFAP) gene is affected by at least three cis-acting elements. A positive regulatory element that is located between nucleotides -1,631 and -1,479 can confer cell type-specific expression on a heterologous gene. A second regulatory element is located between nucleotides -97 and -80. The third is a negative regulatory element that is located within the first intron of the gene. Deletion of this element activates GFAP expression in HeLa cells, and affects promoter function in glioma cells. 相似文献
2.
High variability in the MHC class II DA beta chain of the brushtail possum (<Emphasis Type="Italic">Trichosurus vulpecula</Emphasis>) 总被引:1,自引:0,他引:1
The diversity of class II major histocompatibility complex (MHC) loci was investigated in the brushtail possum, an important
marsupial pest species in New Zealand. Immunocontraception, a form of fertility control that generates an autoimmune response,
is being developed as a population control method for the possum. Because the immune response is partly under genetic control,
an understanding of immunogenetics in possum will be crucial to the development of immunocontraceptive vaccines. MHC molecules
are critical in the vertebrate immune response. Class II MHC molecules bind and present exogenously derived peptides to T
lymphocytes and may be important in the presentation of immunocontraceptives. We used polymerase chain reaction primers designed
to amplify the peptide binding region of possum class II MHC genes to isolate sequences from 49 animals. We have previously
described 19 novel alleles from the DAB locus in the possum (Holland et al., Immunogenetics 60:449–460, 2008). Here, we report on another 11 novel alleles isolated from possum DAB, making this the most diverse marsupial locus described so far. This high level of diversity indicates that DAB is an important MHC locus in the possum and will need to be taken into account in the design of immunocontraceptive vaccines. 相似文献
3.
Louise Lafortune Steven Martin Sarah Kelly Isla Kuhn Olivia Remes Andy Cowan Carol Brayne 《PloS one》2016,11(2)
Background
Smoking, alcohol consumption, poor diet and low levels of physical activity significantly contribute to the burden of illness in developed countries. Whilst the links between specific and multiple risk behaviours and individual chronic conditions are well documented, the impact of these behaviours in mid-life across a range of later life outcomes has yet to be comprehensively assessed. This review aimed to provide an overview of behavioural risk factors in mid-life that are associated with successful ageing and the primary prevention or delay of disability, dementia, frailty and non-communicable chronic conditions.Methods
A literature search was conducted to identify cohort studies published in English since 2000 up to Dec 2014. Multivariate analyses and a minimum follow-up of five years were required for inclusion. Two reviewers screened titles, abstracts and papers independently. Studies were assessed for quality. Evidence was synthesised by mid-life behavioural risk for a range of late life outcomes.Findings
This search located 10,338 individual references, of which 164 are included in this review. Follow-up data ranged from five years to 36 years. Outcomes include dementia, frailty, disability and cardiovascular disease. There is consistent evidence of beneficial associations between mid-life physical activity, healthy ageing and disease outcomes. Across all populations studied there is consistent evidence that mid-life smoking has a detrimental effect on health. Evidence specific to alcohol consumption was mixed. Limited, but supportive, evidence was available relating specifically to mid-life diet, leisure and social activities or health inequalities.Conclusions
There is consistent evidence of associations between mid-life behaviours and a range of late life outcomes. The promotion of physical activity, healthy diet and smoking cessation in all mid-life populations should be encouraged for successful ageing and the prevention of disability and chronic disease. 相似文献4.
Quy RJ Cowan DP Haynes PJ Sturdee AP Chalmers RM Bodley-Tickell AT Bull SA 《Journal of wildlife diseases》1999,35(4):660-670
The potential of Norway rats (Rattus norvegicus) to spread the parasite Cryptosporidium parvum was investigated by examining parasite prevalence in relation to the structure and movements of three permanent rat populations living on farmland in Warwickshire (UK) from October 1994 to March 1997. One population lived among a group of farm buildings housing cattle, while the other two had no contact with livestock, one living around a pond and its outflowing stream and the other on a rubbish tip. Overall, parasite occurrence was 24% (n = 438), but it varied according to body weight (age) with 40% of juveniles (< or =100 g) infected decreasing to 12% for adults >400 g, suggesting that actively breeding populations are potentially more likely to spread the parasite than non-breeding populations. There was no difference in prevalence between the three populations. The parasite was detected in more males (29%) than females (19%). Seasonally, on the livestock farm, prevalence was significantly lower in autumn (10%), but varied little (31-36%) from winter to summer. In contrast, on the arable farm, prevalence peaked in summer (50%) with a trough in winter (6%). Infection in rats appeared to last <67 days. Rats living on the livestock farm had home ranges largely confined to the cattle sheds, thereby maintaining a potential source of infection for livestock if rodent control was not part of a decontamination program. Equally, rats living around the pond on the arable farm provided a source of oocysts to contaminate the pond water, as well as being able to carry the parasite to nearby farm buildings or even to neighboring farms. 相似文献
5.
Hwang SI Lundgren DH Mayya V Rezaul K Cowan AE Eng JK Han DK 《Molecular & cellular proteomics : MCP》2006,5(6):1131-1145
Identification and characterization of the nuclear proteome is important for detailed understanding of multiple signaling events in eukaryotic cells. Toward this goal, we extensively characterized the nuclear proteome of human T leukemia cells by sequential extraction of nuclear proteins with different physicochemical properties using three buffer conditions. This large scale proteomic study also tested the feasibility and technical challenges associated with stable isotope labeling by amino acids in cell culture (SILAC) to uncover quantitative changes during apoptosis. Analyzing proteins from three nuclear fractions extracted from naive and apoptotic cells generated 780,530 MS/MS spectra that were used for database searching using the SEQUEST algorithm. This analysis resulted in the identification and quantification of 1,174 putative nuclear proteins. A number of known nuclear proteins involved in apoptosis as well as novel proteins not known to be part of the nuclear apoptotic machinery were identified and quantified. Consistent with SILAC-based quantifications, immunofluorescence staining of nucleus, mitochondria, and some associated proteins from both organelles revealed a dynamic recruitment of mitochondria into nuclear invaginations during apoptosis. 相似文献
6.
Understanding how animals respond to fire is crucial for conservation efforts in fire-prone regions across the world. How fire affects animal movement is of particular interest, as it determines access to resources, exposure to risks, and connectivity of populations. We report on observations of the movement patterns and habitat selection of two northern quolls (Dasyurus hallucatus, an endangered marsupial predator), one male and one female, in the Pilbara region of Western Australia. We employed GPS tracking and integrated step selection functions to analyse habitat preferences in relation to fire, and used accelerometry data to assess the energetic costs of using burnt areas. The male northern quoll avoided recently burnt areas, likely due to increased energetic demands and predation risks during the breeding season. In contrast, the female northern quoll neither avoided nor preferred burnt areas, but showed a preference for rocky areas. The female appeared to move through burnt areas to access suitable breeding habitat. The movement patterns observed in the two individuals might reflect a broader pattern of sex-specific responses to fire, but further research is required to confirm how general the pattern is. Our observations indicate that fire can influence northern quoll movement, with female dependence on rocky areas increasing use of suboptimal habitats, and male avoidance of burnt areas raising potential implications for breeding dispersal and population dynamics. Given the expected increases in fire size and frequency, further research on northern quoll responses to fire in the Pilbara is needed to determine if the pattern we observed is consistent across the broader population. 相似文献
7.
8.
The soil and plant determinants of community structures of the dominant actinobacteria in Marion Island terrestrial habitats, Sub-Antarctica 总被引:2,自引:0,他引:2
Marion Island is a Sub-Antarctic island made up of distinct ecological habitats based on soil physiochemical, plant cover and physical characteristics. The microbial diversity and ecological determinants in this harsh Sub-Antarctic environment are largely uncharacterized. Actinobacteria have diverse ecological functions related to soil and plant functioning. This study was aimed at characterizing the diversity and community structures of the dominant actinobacteria in the distinct habitats and to identify their determinant soil and plant characteristics. Using the 16S rRNA gene, the denaturing gradient gel electrophoresis patterns and clone library diversity were correlated with the soil and plant characteristics. Multivariate statistical methods were also used to identify determinant soil and plant characteristics. Salinity and pH were the most important soil determinants, and a number of important site-specific plant species may have been important. The Coastal Fellfield Habitat was dominated by sequences of the suborders Micrococcineae (44%) and Propionibacterineae (18%), with salinity identified as the principal determinant. The Cotula Herbfield Habitat was dominated by Frankineae (37%) and Streptosporangineae (38%), which were correlated with organic nutrient concentrations. The Wet Mire Habitat was dominated by Acidimicrobineae (61%), with moisture and organic carbon content as principal components. Culture-dependent studies were complementary to culture-independent studies with the majority of actinobacteria isolated not identified in 16S rRNA gene clone libraries. This study demonstrates how the soil physiochemical characteristics and plant species independently determine the community structures of the dominant actinobacteria in distinct ecological habitats. These factors subsequently influence their ecological adaptation, roles and functions. 相似文献
9.
Plant hormone homeostasis and the control of avocado fruit size 总被引:1,自引:0,他引:1
Control of plant hormone homeostasis is crucial for normal organdevelopment in plants. To elucidate the contribution of plant hormonehomeostasis to fruit growth, tissue distribution and activity of xanthinedehydrogenase (XDH), abscisic aldehyde (AB-ald)- and indole acetaldehyde(IA-ald) oxidase, and cytokinin oxidase (CKOX) were determined in seed, seedcoat and mesocarp of normal 'Hass avocado and its small-fruitphenotype during the linear phase of growth. Activity of these enzymes wasrelated to the tissue content of indole-3-acetic acid (IAA) and abscisic acid(ABA). IA-ald oxidase was present only in seed tissue whereas AB-ald oxidase andXDH activity was found in seed and mesocarp tissue. Seed of the small'Hass fruit had increased XDH and AB-ald oxidase activity and highendogenous ABA, but reduced IA-ald oxidase activity and adenine. There was nodifference in seed, seed coat and mesocarp CKOX activity between normal andsmall fruit. Inhibition of XDH activity in whole fruit by treatment withallopurinol decreased IAA and increased ABA of seed tissue. In mesocarp ofripening fruit allopurinol increased ABA and IAA but had no effect on levels ofiP. Results indicate that activity of IA-ald and AB-ald oxidases in avocadofruit contribute to maintenance of the IAA/ABA ratio in seed and mesocarp tissueand that increased AB-ald oxidase, or reduced IA-ald oxidase, may be part of thesyndrome associated with the appearance of a small-fruit phenotype. 相似文献
10.