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91.
Janine de Zeeuw Till F. Omansen Marlies Douwstra Yves T. Barogui Chantal Agossadou Ghislain E. Sopoh Richard O. Phillips Christian Johnson K. Mohammed Abass Paul Saunderson Pieter U. Dijkstra Tjip S. van der Werf Ymkje Stientstra 《PLoS neglected tropical diseases》2014,8(11)
BackgroundBuruli ulcer may induce severe disabilities impacting on a person''s well-being and quality of life. Information about long-term disabilities and participation restrictions is scanty. The objective of this study was to gain insight into participation restrictions among former Buruli ulcer patients in Ghana and Benin.MethodsIn this cross-sectional study, former Buruli ulcer patients were interviewed using the Participation Scale, the Buruli Ulcer Functional Limitation Score to measure functional limitations, and the Explanatory Model Interview Catalogue to measure perceived stigma. Healthy community controls were also interviewed using the Participation Scale. Trained native interviewers conducted the interviews. Former Buruli ulcer patients were eligible for inclusion if they had been treated between 2005 and 2011, had ended treatment at least 3 months before the interview, and were at least 15 years of age.ResultsIn total, 143 former Buruli ulcer patients and 106 community controls from Ghana and Benin were included in the study. Participation restrictions were experienced by 67 former patients (median score, 30, IQR; 23;43) while 76 participated in social life without problems (median score 5, IQR; 2;9). Most restrictions encountered related to employment. Linear regression showed being female, perceived stigma, functional limitations, and larger lesions (category II) as predictors of more participation restrictions.ConclusionPersisting participation restrictions were experienced by former BU patients in Ghana and Benin. Most important predictors of participation restrictions were being female, perceived stigma, functional limitations and larger lesions. 相似文献
92.
Veroniek Spoorenberg Marlies E. J. L. Hulscher Ronald B. Geskus Theo M. de Reijke Brent C. Opmeer Jan M. Prins Suzanne E. Geerlings 《PloS one》2015,10(12)
Background
Up to 50% of hospital antibiotic use is inappropriate and therefore improvement strategies are urgently needed. We compared the effectiveness of two strategies to improve the quality of antibiotic use in patients with a complicated urinary tract infection (UTI).Methods
In a multicentre, cluster-randomized trial 19 Dutch hospitals (departments Internal Medicine and Urology) were allocated to either a multi-faceted strategy including feedback, educational sessions, reminders and additional/optional improvement actions, or a competitive feedback strategy, i.e. providing professionals with non-anonymous comparative feedback on the department’s appropriateness of antibiotic use. Retrospective baseline- and post-intervention measurements were performed in 2009 and 2012 in 50 patients per department, resulting in 1,964 and 2,027 patients respectively. Principal outcome measures were nine validated guideline-based quality indicators (QIs) that define appropriate antibiotic use in patients with a complicated UTI, and a QI sumscore that summarizes for each patient the appropriateness of antibiotic use.Results
Performance scores on several individual QIs showed improvement from baseline to post-intervention measurements, but no significant differences were found between both strategies. The mean patient’s QI sum score improved significantly in both strategy groups (multi-faceted: 61.7% to 65.0%, P = 0.04 and competitive feedback: 62.8% to 66.7%, P = 0.01). Compliance with the strategies was suboptimal, but better compliance was associated with more improvement.Conclusion
The effectiveness of both strategies was comparable and better compliance with the strategies was associated with more improvement. To increase effectiveness, improvement activities should be rigorously applied, preferably by a locally initiated multidisciplinary team.Trial Registration
Nederlands Trial Register 1742 相似文献93.
Claudia Hoffmann Marlies Galle Sabrina Dilling Rina K?ppeli Andreas J. Müller Pascal Songhet Rudi Beyaert Wolf-Dietrich Hardt 《PloS one》2010,5(8)
The innate immune system is of vital importance for protection against infectious pathogens. Inflammasome mediated caspase-1 activation and subsequent release of pro-inflammatory cytokines like IL-1β and IL-18 is an important arm of the innate immune system. Salmonella enterica subspecies 1 serovar Typhimurium (S. Typhimurium, SL1344) is an enteropathogenic bacterium causing diarrheal diseases. Different reports have shown that in macrophages, S. Typhimurium may activate caspase-1 by at least three different types of stimuli: flagellin, the type III secretion system 1 (T1) and the T1 effector protein SopE. However, the relative importance and interdependence of the different factors in caspase-1 activation is still a matter of debate. Here, we have analyzed their relative contributions to caspase-1 activation in LPS-pretreated RAW264.7 macrophages. Using flagellar mutants (fliGHI, flgK) and centrifugation to mediate pathogen-host cell contact, we show that flagellins account for a small part of the caspase-1 activation in RAW264.7 cells. In addition, functional flagella are of key importance for motility and host cell attachment which is a prerequisite for mediating caspase-1 activation via these three stimuli. Using site directed mutants lacking several T1 effector proteins and flagellin expression, we found that SopE elicits caspase-1 activation even when flagellins are absent. In contrast, disruption of essential genes of the T1 protein injection system (invG, sipB) completely abolished caspase-1 activation. However, a robust level of caspase-1 activation is retained by the T1 system (or unidentified T1 effectors) in the absence of flagellin and SopE. T1-mediated inflammasome activation is in line with recent work by others and suggests that the T1 system itself may represent the basic caspase-1 activating stimulus in RAW264.7 macrophages which is further enhanced independently by SopE and/or flagellin. 相似文献
94.
Greywe D Kreutz J Banduhn N Krauledat M Scheel J Schroeder KR Wolf T Reisinger K 《Mutation research》2012,747(1):118-134
The hen's egg test for analysis of micronucleus formation (HET-MN) was developed several years ago to provide an alternative test system to the in vivo micronucleus test. In order to assess its applicability and robustness, a study was carried out at the University of Osnabrueck (lab A) and at the laboratories of Henkel AG & Co. KGaA (lab B). Following transfer of the method to lab B, a range of test substances that had been pre-tested at lab A, were tested at Henkel: the genotoxins cyclophosphamide, dimethylbenz(a)anthracene, methotrexate, acrylamide, azorubin, N-nitroso-dimethylamine and the non-genotoxins, orange G and isopropyl myristate. In a second phase, additional compounds with known in vivo properties were examined in both labs: the non-genotoxin, ampicillin, the "irrelevant" positives, isophorone and 2,4-dichlorophenol ("irrelevant" means positive in standard in vitro tests, but negative in vivo), the clastogen p-chloroaniline, and the aneugens carbendazim and vinorelbine. All substances were correctly predicted in both labs with respect to their in vivo genotoxic properties, indicating that the HET-MN may have an improved predictivity compared with current standard in vitro test systems. The results support the promising role of the HET-MN assay as a supplement to existing test batteries. 相似文献
95.
A multiparameter screening assay to assess the cytokine-induced expression of endothelial cell adhesion molecules 总被引:2,自引:0,他引:2
Compounds which inhibit endothelial cell inflammatory responses are believed to be of therapeutic value. The cell adhesion molecules E-selectin, ICAM-1, and VCAM-1 play important roles in inflammatory reactions by mediating leukocyte-endothelial interactions. To identify compounds which inhibit the expression of these adhesion molecules following cytokine stimulation we developed an assay which measures E-selectin, ICAM-1, and VCAM-1 in the same experiment. For this, we have taken advantage of the technology of time-resolved fluorimetry, which allows detection of several parameters in parallel, employing anti-E-selectin antibody labeled with europium, and anti-ICAM-1 and anti-VCAM-1 labeled with samarium and terbium, respectively. These antibodies were used to detect the respective antigens in human endothelial cells stimulated with TNFalpha or IL-1beta. In cross-competition assays these antibodies were found to bind specifically to TNF- or IL-1-stimulated cells. This assay, in which three parameters are measured in the same experiment, proved to be robust with signal to noise ratios of 25-35 for E-Selectin, 4-8 for ICAM-1, and 3-9 for VCAM-1. The assay proved to be reproducible in high-throughput screening. The experience with this assay demonstrates that multiple parameters can be measured in an enzyme-linked immunosorbent assay-type assay on cells by using time-resolved fluorimetry. The possibility of obtaining several parameters from one experiment is feasible under high-throughput screening conditions and is of interest for other experimental setups in which the simultaneous measurement of several parameters is desired. 相似文献
96.
Summary The distribution of sclerotome and neural crest cells of avian embryos was studied by light and electron microscopy. Sclerotome cells radiated from the somites towards the notochord, to occupy the perichordal space. Neural crest cells, at least initially, also entered cell-free spaces. At the cranial somitic levels they moved chiefly dorsal to the somites, favouring the rostral part of each somite. These cells did not approach the perichordal space. More caudally (i.e. trunk levels), neural crest cells initially moved ventrally between the somites and neural tube. Adjacent to the caudal half of each somite, these cells penetrated no further than the myosclerotomal border, but opposite the rostral somite half, they were found next to the sclerotome almost as far ventrally as the notochord. However, they did not appear to enter the perichordal space, in contrast to sclerotome cells.When tested in vitro, sclerotome cells migrated towards notochords co-cultured on fibronectin-rich extracellular material, and on collagen gels. In contrast, neural crest cells avoided co-cultured notochords. This avoidance was abolished by inclusion of testicular hyaluronidase and chondroitinase ABC in the culture medium, but not by hyaluronidase from Streptomyces hyalurolyticus. The results suggest that sclerotome and neural crest mesenchyme cells have a different distribution with respect to the notochord, and that differential responses to notochordal extracellular material, possibly chondroitin sulphate proteoglycan, may be responsible for this. 相似文献
97.
Céline Richard-Molard Sylvie Wuillème Christina Scheel Peter M. Gresshoff Jean-François Morot-Gaudry Anis M. Limami 《Planta》1999,209(4):389-398
Nitrogen is known to modulate plant development and resistance to pathogens. Four selected lines (Alg, NS1, NR1 and NR2)
of chicory (Cichorium intybus L.) were grown on low (0.6 mM) and high (3 mM) NO−
3 nutrition in order to study the effect of N on the expression of three traits, namely, shoot/root ratio, chicon morphology
and resistance to soft rot caused by Erwinia sp. For all genotypes, increasing N supply led to a higher shoot/root ratio, resulting from an increased shoot biomass but
with no effect on root growth. In contrast, the effect of N on chicon morphology and resistance to bacteria was genotype-dependent
and we distinguished two groups of lines according to their phenotypic characteristics. In the group consisting of NR1 and
NR2, increasing NO−
3 supply during the vegetative phase made the chicon morphology switch from an opened to a closed type while resistance to
bacteria was not affected by N supply. In the NS1 and Alg group, the effect of N on chicon morphology was the opposite to
that observed in the NR1-NR2 group while NS1 and Alg exhibited a partial resistance to Erwinia sp., only expressing soft-rot disease when the N supply reached 3 mM. Characterization by DNA amplification fingerprinting
(DAF) allowed the generation of 110 polymorphic bands and confirmed that the lines NR1 and NR2, on the one hand, and NS1 and
Alg, on the other hand, belong to two distinct genetic groups. The DAF results indicate that chicon morphology and partial
resistance to Erwinia sp. are complex traits which would be amenable to quantitative trait loci analysis. The split growth phase of chicory means
that any changes in chicon related to N supply during vegetative growth were mediated by a root-originating signal. No variation
in root carbon content among genotypes and NO−
3 treatments was observed. In contrast, differences in root N content revealed the same grouping of the chicory lines, NR1
and NR2 being systematically richer in amino acids and NO−
3 than NS1 and Alg. However, no correlation existed between N compounds and chicon morphology or pathology if all genotypes
were considered together. Thus, the effect of N on plant development and pathology as well as putative identified signals
might be specific for a genotype. Our study indicates that it is necessary to consider the genetic variability within a species
in any signalling-pathway research.
Received: 16 December 1998 / Accepted: 24 March 1999 相似文献
98.
99.
Discovery of a nonclassical siderophore, legiobactin, produced by strains of Legionella pneumophila 下载免费PDF全文
The mechanisms by which Legionella pneumophila, a facultative intracellular parasite and the agent of Legionnaires' disease, acquires iron are largely unexplained. Several earlier studies indicated that L. pneumophila does not elaborate siderophores. However, we now present evidence that supernatants from L. pneumophila cultures can contain a nonproteinaceous, high-affinity iron chelator. More specifically, when aerobically grown in a low-iron, chemically defined medium (CDM), L. pneumophila secretes a substance that is reactive in the chrome azurol S (CAS) assay. Importantly, the siderophore-like activity was only observed when the CDM cultures were inoculated to relatively high density with bacteria that had been grown overnight to log or early stationary phase in CDM or buffered yeast extract. Inocula derived from late-stationary-phase cultures, despite ultimately growing, consistently failed to result in the elaboration of siderophore-like activity. The Legionella CAS reactivity was detected in the culture supernatants of the serogroup 1 strains 130b and Philadelphia-1, as well as those from representatives of other serogroups and other Legionella species. The CAS-reactive substance was resistant to boiling and protease treatment and was associated with the <1-kDa supernatant fraction. As would also be expected for a siderophore, the addition of 0.5 or 2.0 microM iron to the cultures repressed the expression of the CAS-reactive substance. Interestingly, the supernatants were negative in the Arnow, Csáky, and Rioux assays, indicating that the Legionella siderophore was not a classic catecholate or hydroxamate and, hence, might have a novel structure. We have designated the L. pneumophila siderophore legiobactin. 相似文献