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161.
Stimulatory and inhibitory action of cytokines on the regulation of hCMV-IE promoter activity in human endothelial cells 总被引:4,自引:0,他引:4
Viral promoters are commonly used as regulatory elements in gene therapy vectors due to their strong activity in various cell lines in vitro. However, transgene expression under the control of viral promoters in vivo has been shown to be limited to a short period of time. Several mechanisms for the transient expression of the delivered transgene may be important including deletion of transduced cells or promoter downregulation. Recently we reported that cytokines may either decrease or increase the activity of the human cytomegalovirus (hCMV) promoter in monocytes depending on the differentiation status of the transduced cells. For many applications, the gene of interest has to be delivered into an inflammatory milieu (tumour, ischaemia/reperfusion, vector-induced inflammation etc.). In this report we investigated the influence of various inflammatory cytokines on the hCMV-IE promoter activity in transduced human primary endothelial cells (Huvec) in vitro, which may be the first target cells after gene transfer into different organs. Cultured cells were infected with an E1-deleted adenoviral vector encoding for E. colibeta-galactosidase (Adbeta-gal) driven by the hCMV-IE promoter and incubated either with or without various cytokines. Our results indicate that interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) downregulate promoter activity in endothelial cells whereas, in contrast, tumour necrosis factor (TNF-alpha), interleukin 1beta (IL-1beta) and interleukin 4 (IL-4) increased the promoter activity. These results suggest that inflammatory processes influence the in vivo expression of transferred viral promoter controlled genes of interest. 相似文献
162.
Eliane R Popa Coen A Stegeman Cees GM Kallenberg Jan Willem Cohen Tervaert 《Arthritis research & therapy》2001,4(2):77-3
Wegener's granulomatosis (WG) is a form of systemic vasculitis. It is characterized by granulomatous inflammation in the upper and lower airways, vasculitis and necrotizing glomerulonephritis, and is strongly associated with antineutrophil cytoplasmic antibodies against proteinase 3. Since the etiology of the disease is not clear, treatment, consisting of corticosteroids and immunosuppressives, is nonspecific and associated with severe side effects. Pinpointing the trigger(s) of the disease would highly improve treatment. Clinical evidence shows that an infectious agent, the bacterium Staphylococcus aureus, is a risk factor for disease relapse, suggesting its involvement in the pathogenesis of WG. Here we review both clinical and experimental data that either indicate or support a role for S. aureus in WG. 相似文献
163.
Poplar and shrub willow energy crops in the United States: field trial results from the multiyear regional feedstock partnership and yield potential maps based on the PRISM‐ELM model 下载免费PDF全文
Timothy A. Volk Bill Berguson Christopher Daly Michael D. Halbleib Raymond Miller Timothy G. Rials Lawrence P. Abrahamson Dan Buchman Marylin Buford Michael W. Cunningham Mark Eisenbies Eric S. Fabio Karl Hallen Justin Heavey Gregg A Johnson Yulia A Kuzovkina Bo Liu Bernie Mcmahon Randy Rousseau Shun Shi Richard Shuren Lawrence B. Smart Glen Stanosz Brain Stanton Bryce Stokes Jeff Wright 《Global Change Biology Bioenergy》2018,10(10):735-751
To increase the understanding of poplar and willow perennial woody crops and facilitate their deployment for the production of biofuels, bioproducts, and bioenergy, there is a need for broadscale yield maps. For national analysis of woody and herbaceous crops production potential, biomass feedstock yield maps should be developed using a common framework. This study developed willow and poplar potential yield maps by combining data from a network of willow and poplar field trials and the modeling power of PRISM‐ELM. Yields of the top three willow cultivars across 17 sites ranged from 3.60 to 14.6 Mg ha?1 yr?1 dry weight, while the yields from 17 poplar trials ranged from 7.5 to 15.2 Mg ha?1 yr?1. Relationships between the environmental suitability estimates from the PRISM‐ELM model and results from field trials had an R2 of 0.60 for poplar and 0.81 for willow. The resulting potential yield maps reflected the range of poplar and willow yields that have been reported in the literature. Poplar covered a larger geographic range than willow, which likely reflects the poplar breeding efforts that have occurred for many more decades using genotypes from a broader range of environments than willow. While the field trial data sets used to develop these models represent the most complete information at the time, there is a need to expand and improve the model by monitoring trials over multiple cutting cycles and across a broader range of environmental gradients. Despite some limitations, the results of these models represent a dramatic improvement in projections of potential yield of poplar and willow crops across the United States. 相似文献
164.
Immunomodulatory effects of inactivated parapoxvirus ovis (ORF virus) on human peripheral immune cells: induction of cytokine secretion in monocytes and Th1-like cells 下载免费PDF全文
Inactivated parapoxvirus ovis (Orf virus; PPVO) recently displayed strong immunostimulating and modulating capacities in several animal models for acute and chronic virus infections through the induction of gamma interferon (IFN-gamma) as a key mediator of antiviral activity. The data presented in this work demonstrate that inactivated PPVO has strong effects on cytokine secretion by human immune cells, including the upregulation of inflammatory and Th1-related cytokines (IFN-gamma, tumor necrosis factor alpha [TNF-alpha], interleukin 6 [IL-6], IL-8, IL-12, and IL-18) as well as anti-inflammatory and Th2-related cytokines (IL-4, IL-10, and IL-1 receptor antagonist [IL-1ra]). Studies on the mechanism of action revealed virus particles to be the effective components of the preparation. The virus particles activate monocytes or other antigen-presenting cells (APC), e.g., plasmacytoid dendritic cells, through signaling over CD14 and a Toll-like receptor and the intracellular presence of certain PPVO-specific components. The activation of monocytes or APC is followed by the release of early proinflammatory cytokines (TNF-alpha, IL-6, and IL-8) as well as the Th1-related cytokines IL-12 and IL-18. Both IL-18 and IL-12 are involved in PPVO-mediated IFN-gamma release by T cells and/or NK cells. The proinflammatory response is accompanied by the induction of anti-inflammatory and Th2-related cytokines (IL-4, IL-10, and IL-1ra), which exert a limiting efffect on the inflammatory response induced by PPVO. We conclude that the induction of a natural immune response with physiologically significant amounts of different cytokines and with antiviral potential might provide advantages over existing antiviral immunotherapies. 相似文献
165.
Summary. Successful cryopreservation of plant shoot tips is dependent upon effective desiccation through osmotic or physical processes.
Microscopy techniques were used to determine the extent of cellular damage and plasmolysis that occurs in peppermint (Mentha × piperita) shoot tips during the process of cryopreservation, using the cryoprotectant plant vitrification solution 2 (PVS2) (30% glycerol,
15% dimethyl sulfoxide, 15% ethylene glycol, 0.4 M sucrose) prior to liquid-nitrogen exposure. The meristem cells were the
smallest and least plasmolyzed cell type of the shoot tips, while the large, older leaf and lower cortex cells were the most
damaged. When treated with cryoprotectant solutions, meristem cells exhibited concave plasmolysis, suggesting that this cell
type has a highly viscous protoplasm, and protoplasts have many cell wall attachment sites. Shoot tip cells were most severely
plasmolyzed after PVS2 treatment, liquid-nitrogen exposure, and warming in 1.2 M sucrose. Successful recovery may be dependent
upon surviving the plasmolytic conditions induced by warming and diluting treated shoot tips in 1.2 M sucrose solutions. In
peppermint shoot tips, clumps of young meristem or young leaf cells survive the cryopreservation process and regenerate plants
containing many shoots. Cryoprotective treatments that favor survival of small, meristematic cells and young leaf cells are
most likely to produce high survival rates after liquid-nitrogen exposure.
Correspondence and reprints: National Center for Genetic Resources Preservation, U.S. Department of Agriculture, 1111 S. Mason
Street, Fort Collins, CO 80521, U.S.A. 相似文献
166.
The structural investigation of an extracellular polysaccharide released during photoautotrophic growth by the cyanobacterium
Nostoc insulare is reported. After 60 days of cultivation, an average yield of purified, desalted, and freeze-dried released polysaccharide
(RPS) of 0.9 g L−1 medium was obtained. The apparent hydrodynamic volume, determined for RPS, was 1.1 × 106 Da, and the average molecular weight was 2.8 × 106 Da. No sulfate and only traces of pyruvate and acetate groups were detectable. A protein content of only 0.7% indicates a
high degree of purity of RPS. The following constituent uronic acids and sugars were identified: glucuronic acid (GlcA), glucose
(Glc), arabinose (Ara), and for the first time, cyanobacterial RPSs 3-O-methyl-arabinose (3-O-Methyl-Ara). Adapted from linkage
analyses of untreated RPS and of RPS treated by means of reduction of uronic acids, mild acid hydrolysis with oxalic acid,
or lithium degradation, respectively, the following partial structure of RPS is proposed, which possesses an arborisation
built by 1,3,4-Glcp and a side chain built by 3-O-Methyl-Araf: →1)-Glcp-(3→1)-Glcp-[(3→1)-3-O-Methyl-Araf](4→1)-GlcAp-(4→). 相似文献
167.
Pauline?AaltenEmail author Inez?HGB?Ramakers Geert?Jan?Biessels Peter?Paul?de Deyn Huiberdina?L?Koek Marcel?GM?OldeRikkert Ania?M?Oleksik Edo?Richard Lieke?L?Smits John?C?van Swieten Laura?K?Teune Aad?van der Lugt Frederik?Barkhof Charlotte?E?Teunissen Nico?Rozendaal Frans?RJ?Verhey Wiesje?M?van der Flier 《BMC neurology》2014,14(1):254
168.
169.
Organism growth and reproduction are often limited by nutrient availability in freshwater ecosystems where, in some cases,
food webs are primarily supported by allochthonous organic matter. Therefore, we hypothesized that the composition of riparian
vegetation would influence the variability of N, P, and fatty acid content of in-stream consumers. Specifically, we predicted
that organisms living in alder streams would have higher levels of N, P, and polyunsaturated fatty acids than organisms in
coniferous streams. To determine this, we sampled fresh and aged leaf litter, periphyton, invertebrates, and cutthroat trout
(Oncorhynchus clarki) from 6 streams in western Washington state: 3 streams had high densities of nitrogen-fixing red alder (Alnus rubra) in the riparian zone, whereas 3 had high densities of conifers. We found fresh alder litter had twice the total polyunsaturated
fatty acid concentrations of hemlock vegetation while there were few statistical differences among aged alder and aged hemlock
vegetation. Multidimensional plots showed fatty acid profiles were unique to vegetation and fish while periphyton and invertebrates
shared the same multidimensional space. We used a mixed model to determine the relative importance of vegetation type (fixed
factor: conifer or alder), trophic levels (fixed factor: periphyton, primary consumer, or fish), and streams (random factor)
on individual fatty acid concentrations. Total polyunsaturated fatty acids, 16:0, 20:1, 20:3n6 and total n3 were the only
fatty acids influenced by stream vegetation (vegetation + stream model or full model). 67% of the fatty acids were best supported
by the trophic + stream model. Nitrogen, P, Ca, Fe, C:N, N:P, and C:N:P were all best supported by the trophic level + stream
model, and Zn was the only nutrient supported best by the full model. Correlations of n3 and n6 fatty acid concentrations
between periphyton and primary consumers, and primary consumers with trout indicated several fatty acid metrics, such as n3:n6,
showed food resources may affect relative fatty acid abundances of consumers. Although vegetation type did not influence relative
fatty acids of stream organisms, the importance of trophic level likely indicates organisms have different physical requirements
for fatty acids. The significance of a random factor, ‘stream,’ suggests that the relative abundances of fatty acids in periphyton,
invertebrates, and trout are stream-specific and are responding to local environmental or communal variables. 相似文献
170.