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1.
Amanda L. McGuire Sophia C. Bennett Sally M. Lansley Natalia D. Popowicz Julius F. Varano della Vergiliana Daniel Wong Y. C. Gary Lee Aron Chakera 《PloS one》2015,10(3)
A major complication of peritoneal dialysis is the development of peritonitis, which is associated with reduced technique and patient survival. The inflammatory response elicited by infection results in a fibrin and debris-rich environment within the peritoneal cavity, which may reduce the effectiveness of antimicrobial agents and predispose to recurrence or relapse of infection. Strategies to enhance responses to antimicrobial agents therefore have the potential to improve patient outcomes. This study presents pre-clinical data describing the compatibility of tPA and DNase in combination with antimicrobial agents used for the treatment of PD peritonitis. tPA and DNase were stable in standard dialysate solution and in the presence of antimicrobial agents, and were safe when given intraperitoneally in a mouse model with no evidence of local or systemic toxicity. Adjunctive tPA and DNase may have a role in the management of patients presenting with PD peritonitis. 相似文献
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Catherine J. Taylor Ben J. Carrick Lesley Galbraith Stephen G. Wilkinson 《FEMS microbiology letters》1993,106(1):65-69
Abstract Reference strains of ' Pseudomonas diazotrophicus ' produce a range of polar lipids atypical of authentic Pseudomonas species. In addition to the phospholipids common in Gram-negative bacteria (phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine), N -methylated derivatives of phosphatidylethanolamine (including phosphatidylcholine) and an ornithine amide lipid are also present. The preponderant ester-bound fatty acid (up to 80% of the total) is cis -vaccenic acid ( cis -octadec-11-enoic acid), while 3-hydroxyoctadecanoic acid is the major amide-bound fatty acid in the ornithine lipid. Possible implications of the data for classification of the organism are discussed. 相似文献
4.
Jye-Lin Hsu Dick J. H. van den Boomen Peter Tomasec Michael P. Weekes Robin Antrobus Richard J. Stanton Eva Ruckova Daniel Sugrue Gavin S. Wilkie Andrew J. Davison Gavin W. G. Wilkinson Paul J. Lehner 《PLoS pathogens》2015,11(4)
Human cytomegalovirus (HCMV) US2, US3, US6 and US11 act in concert to prevent immune recognition of virally infected cells by CD8+ T-lymphocytes through downregulation of MHC class I molecules (MHC-I). Here we show that US2 function goes far beyond MHC-I degradation. A systematic proteomic study using Plasma Membrane Profiling revealed US2 was unique in downregulating additional cellular targets, including: five distinct integrin α-chains, CD112, the interleukin-12 receptor, PTPRJ and thrombomodulin. US2 recruited the cellular E3 ligase TRC8 to direct the proteasomal degradation of all its targets, reminiscent of its degradation of MHC-I. Whereas integrin α-chains were selectively degraded, their integrin β1 binding partner accumulated in the ER. Consequently integrin signaling, cell adhesion and migration were strongly suppressed. US2 was necessary and sufficient for degradation of the majority of its substrates, but remarkably, the HCMV NK cell evasion function UL141 requisitioned US2 to enhance downregulation of the NK cell ligand CD112. UL141 retained CD112 in the ER from where US2 promoted its TRC8-dependent retrotranslocation and degradation. These findings redefine US2 as a multifunctional degradation hub which, through recruitment of the cellular E3 ligase TRC8, modulates diverse immune pathways involved in antigen presentation, NK cell activation, migration and coagulation; and highlight US2’s impact on HCMV pathogenesis. 相似文献
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Plant Ecology - In forests, the majority of fine roots are located within the upper soil horizons, and fine root biomass decreases with depth. We evaluated spatial patterns in the distribution of... 相似文献
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Cre recombinase (Cre)-mediated targeted insertion of a transgene is a powerful technique that can be used to tailor genomes. When combined with somatic cell nuclear transfer it could offer an efficient way to generate transgenic livestock with site-specific genetic modifications that are free of antibiotic selection markers. We have engineered primary bovine fibroblasts to contain a chromosomal acceptor site with incompatible loxP/lox2272 sites for Cre-mediated cassette exchange and show for the first time that Cre-mediated targeting can be applied in these acceptor cells. Molecular characterization of the resulting cell clones revealed Cre-mediated transgene insertion efficiencies of up to 98% when antibiotic selection was used to identify transgene containing cell clones. Most clonal lines also contained random insertions of the targeting and Cre expression plasmids with only about 10% of the clones being exclusively modified by the intended targeted insertion. This targeting efficiency was sufficient to enable the isolation of correctly targeted clones without the help of antibiotic selection. Therefore, this recombinase-mediated insertion strategy has the potential to produce transgenic cattle from antibiotic selection marker-free somatic cells with transgenes inserted into proven genomic loci ensuring reliable expression levels. 相似文献
7.
Sally Adams Trudie Allen Garry C. Whitelam 《The Plant journal : for cell and molecular biology》2009,60(2):257-267
Flowering in Arabidopsis is accelerated by a reduced ratio of red light to far-red light (R/FR), which indicates the proximity of competitive vegetation. By exploiting the natural genetic variation in flowering time responses to low R/FR, we obtained further insight into the complex pathways that fine-tune the transition to flowering in Arabidopsis. The Bla-6 ecotype does not flower significantly earlier in response to low R/FR, but is still able to display other features of shade avoidance, suggesting branching of low R/FR signalling. Here we show that the muted flowering response of Bla-6 is due to high levels of the floral repressor FLOWERING LOCUS C (FLC), conferred by a combination of functional FLC and FRIGIDA ( FRI ) alleles with a 'weak' FY allele. The Bla-6 FY allele encodes a protein with a corrupted WW binding domain, and we provide evidence that this locus plays a key role in the natural variation in light quality-induced flowering in Arabidopsis. In Bla-6, FLC blocks promotion to flowering by reduced R/FR by inhibiting expression of the floral integrator FLOWERING LOCUS T ( FT ) in a dose-dependent manner. Reduction of FLC removes this obstruction, and Bla6 plants then exhibit strong induction of FT and flower early in response to a low R/FR signal. This paper illustrates the intricate interaction of environmental signals and genetic factors to regulate flowering in Arabidopsis. 相似文献
8.
Amino sugars in the cell walls of Pseudomonas species 总被引:3,自引:0,他引:3
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W. Camac Wilkinson 《BMJ (Clinical research ed.)》1923,1(3251):674-676
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