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181.
Sander Croes Ruud H Deurenberg Marie-Louise L Boumans Patrick S Beisser Cees Neef Ellen E Stobberingh 《BMC microbiology》2009,9(1):229
Background
Since bacteria embedded in biofilms are far more difficult to eradicate than planktonic infections, it would be useful to know whether certain Staphylococcus aureus lineages are especially involved in strong biofilm formation. For this reason, in vitro biofilm formation of 228 clinical S. aureus isolates of distinct clonal lineages was investigated. 相似文献182.
Cushing TD Baichwal V Berry K Billedeau R Bordunov V Broka C Cardozo M Cheng P Clark D Dalrymple S DeGraffenreid M Gill A Hao X Hawley RC He X Jaen JC Labadie SS Labelle M Lehel C Lu PP McIntosh J Miao S Parast C Shin Y Sjogren EB Smith ML Talamas FX Tonn G Walker KM Walker NP Wesche H Whitehead C Wright M Browner MF 《Bioorganic & medicinal chemistry letters》2011,21(1):417-422
A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKβ. In this Letter we document our early efforts at optimization of the quinoline core, the imidazole and the semithiocarbazone moiety. Most potency gains came from substitution around the 6- and 7-positions of the quinoline ring. Replacement of the semithiocarbazone with a semicarbazone decreased potency but led to some measurable exposure. 相似文献
183.
Molecular dynamics simulations of water confined in two hydrophilic cylindrical pores—PH and PL—that differ in their silanol
surface concentration (7.6 and 3.0 nm−2, respectively) have been performed at 300 K. A strong interaction of interfacial water molecules with the pore was systematically
found and gives rise to a layering effect, a significant distortion of both the hydrogen bond network (HBN) and the tetrahedral
structure of these water molecules, and a corresponding subdiffusive mean square displacement along the main axis of the pores.
By contrast, water molecules in the inner part of both pores were found to behave similarly to bulk water. The HBN and the
tetrahedral configuration of water were more gradually distorted in the PL pore given the larger heterogeneity and rugosity
of the surface, and the number of water–pore hydrogen bonds did not scale linearly with the silanol surface concentration
of the pores, in part because of the close proximity between silanols in the PH pore. With the PL pore, the dynamic slowing
down of water was found consistent with the experiment, suggesting that it provides a better model for the cylindrical MCM-41
mesopores. The structural and dynamical properties of water vary little with the silica force field. 相似文献
184.
Warmuth V Eriksson A Bower MA Cañon J Cothran G Distl O Glowatzki-Mullis ML Hunt H Luís C do Mar Oom M Yupanqui IT Ząbek T Manica A 《PloS one》2011,6(3):e18194
The role of European wild horses in horse domestication is poorly understood. While the fossil record for wild horses in Europe prior to horse domestication is scarce, there have been suggestions that wild populations from various European regions might have contributed to the gene pool of domestic horses. To distinguish between regions where domestic populations are mainly descended from local wild stock and those where horses were largely imported, we investigated patterns of genetic diversity in 24 European horse breeds typed at 12 microsatellite loci. The distribution of high levels of genetic diversity in Europe coincides with the distribution of predominantly open landscapes prior to domestication, as suggested by simulation-based vegetation reconstructions, with breeds from Iberia and the Caspian Sea region having significantly higher genetic diversity than breeds from central Europe and the UK, which were largely forested at the time the first domestic horses appear there. Our results suggest that not only the Eastern steppes, but also the Iberian Peninsula provided refugia for wild horses in the Holocene, and that the genetic contribution of these wild populations to local domestic stock may have been considerable. In contrast, the consistently low levels of diversity in central Europe and the UK suggest that domestic horses in these regions largely derive from horses that were imported from the Eastern refugium, the Iberian refugium, or both. 相似文献
185.
186.
Tracey A. Willis Kieren G. Hollingsworth Anna Coombs Marie-Louise Sveen S?ren Andersen Tanya Stojkovic Michelle Eagle Anna Mayhew Paulo L. de Sousa Liz Dewar Jasper M. Morrow Christopher D. J. Sinclair John S. Thornton Kate Bushby Hanns Lochmüller Michael G. Hanna Jean-Yves Hogrel Pierre G. Carlier John Vissing Volker Straub 《PloS one》2013,8(8)
Background
Outcome measures for clinical trials in neuromuscular diseases are typically based on physical assessments which are dependent on patient effort, combine the effort of different muscle groups, and may not be sensitive to progression over short trial periods in slow-progressing diseases. We hypothesised that quantitative fat imaging by MRI (Dixon technique) could provide more discriminating quantitative, patient-independent measurements of the progress of muscle fat replacement within individual muscle groups.Objective
To determine whether quantitative fat imaging could measure disease progression in a cohort of limb-girdle muscular dystrophy 2I (LGMD2I) patients over a 12 month period.Methods
32 adult patients (17 male;15 female) from 4 European tertiary referral centres with the homozygous c.826C>A mutation in the fukutin-related protein gene (FKRP) completed baseline and follow up measurements 12 months later. Quantitative fat imaging was performed and muscle fat fraction change was compared with (i) muscle strength and function assessed using standardized physical tests and (ii) standard T1-weighted MRI graded on a 6 point scale.Results
There was a significant increase in muscle fat fraction in 9 of the 14 muscles analyzed using the quantitative MRI technique from baseline to 12 months follow up. Changes were not seen in the conventional longitudinal physical assessments or in qualitative scoring of the T1w images.Conclusions
Quantitative muscle MRI, using the Dixon technique, could be used as an important longitudinal outcome measure to assess muscle pathology and monitor therapeutic efficacy in patients with LGMD2I. 相似文献187.
Rul F Ben-Yahia L Chegdani F Wrzosek L Thomas S Noordine ML Gitton C Cherbuy C Langella P Thomas M 《The Journal of biological chemistry》2011,286(12):10288-10296
The thermophilic lactic acid bacterium Streptococcus thermophilus is widely and traditionally used in the dairy industry. Despite the vast level of consumption of S. thermophilus through yogurt or probiotic functional food, very few data are available about its physiology in the gastrointestinal tract (GIT). The objective of the present work was to explore both the metabolic activity and host response of S. thermophilus in vivo. Our study profiles the protein expression of S. thermophilus after its adaptation to the GIT of gnotobiotic rats and describes the impact of S. thermophilus colonization on the colonic epithelium. S. thermophilus colonized progressively the GIT of germ-free rats to reach a stable population in 30 days (10(8) cfu/g of feces). This progressive colonization suggested that S. thermophilus undergoes an adaptation process within GIT. Indeed, we showed that the main response of S. thermophilus in the rat's GIT was the massive induction of the glycolysis pathway, leading to formation of lactate in the cecum. At the level of the colonic epithelium, the abundance of monocarboxylic acid transporter mRNAs (SLC16A1 and SLC5A8) and a protein involved in the cell cycle arrest (p27(kip1)) increased in the presence of S. thermophilus compared with germ-free rats. Based on different mono-associated rats harboring two different strains of S. thermophilus (LMD-9 or LMG18311) or weak lactate-producing commensal bacteria (Bacteroides thetaiotaomicron and Ruminococcus gnavus), we propose that lactate could be a signal produced by S. thermophilus and modulating the colon epithelium. 相似文献
188.
Antimicrobial usage is common in Asian aquaculture. This study aimed to determine the quality of antimicrobial products used by Vietnamese striped catfish (Pangasianodon hypophthalmus) farmers. Twenty one antimicrobial products (11 products contained a single antimicrobial and 10 products contained a mixture of two different antimicrobials) commonly used by catfish farmers were obtained from so-called chemical shops located in the Mekong Delta, Vietnam. Ultra High Performance Liquid Chromatography Mass Spectrometry was used to analyze concentration of sulfonamides, trimethoprim, amoxicillin, cefalexin and ciprofloxacin whereas concentrations of florfenicol and doxycycline were analyzed by High Performance Liquid Chromatography with UV detection. Results revealed that only 4/11 products with a single antimicrobial and 2/10 products with a mixture of antimicrobials contained active substances within ±10% of the concentration declared on the product label. Two products with antimicrobial mixtures did not contain any of the declared antimicrobials. Comparing two batches, analysis of 11 products revealed that only one product contained a concentration of active compound that varied with less than 10% in both batches. Several product labels provided inadequate information on how to calculate therapeutic dosage and further stated withdrawal time despite lack of pharmacokinetic data on the antimicrobials in catfish. There is an urgent need to strengthen approval procedures and in particular regularly to monitor the quality of antimicrobials used in Vietnamese aquaculture. 相似文献
189.
Joachim Rudolf Göthert Lewin Eisele Ludger Klein-Hitpass Stefanie Weber Marie-Louise Zesewitz Ludger Sellmann Alexander Röth Hanspeter Pircher Ulrich Dührsen Jan Dürig 《Cancer immunology, immunotherapy : CII》2013,62(11):1697-1709
Altered numbers and functions of T cells have previously been demonstrated in chronic lymphocytic leukemia (CLL) patients. However, dynamics and specific T-cell subset alterations have not been studied in great detail. Therefore, we studied CLL blood lymphocyte subsets of individual patients in a longitudinal manner. Dynamic expansions of blood CD4 + and CD8 + T-cell numbers were consistently associated with a progressively increasing CLL leukemic compartment. Interestingly, the T-cell subset expansion over time was more pronounced in CD38 + CLL. Additionally, we performed gene expression profiling of CD3 + T cells of CLL patients and normal donors. Using gene set enrichment analysis, we found significant enrichment of genes with higher expression in CLL T cells within CD8+ effector memory and terminal effector T-cell gene signatures. In agreement with these data, we observed a marked expansion of phenotypic CD8 + effector memory T cells in CLL by flow cytometry. Moreover, we observed that increments of CD8 + effector memory T cells in human CLL and also mouse CLL (Eμ-TCL1 model) were due to an expansion of the inhibitory killer cell lectin-like receptor G1 (KLRG1) expressing cellular subset. Furthermore, higher plasma levels of the natural KLRG1 ligand E-cadherin were detected in CLL patients compared to normal donor controls. The predominance of KLRG1+ expression within CD8+ T cells in conjunction with increased systemic soluble E-cadherin might significantly contribute to CLL immune dysfunction and might additionally represent an important component of the CLL microenvironment. 相似文献
190.
Renaud Becquet Ruth Bland Valériane Leroy Nigel C. Rollins Didier K. Ekouevi Anna Coutsoudis Fran?ois Dabis Hoosen M. Coovadia Roger Salamon Marie-Louise Newell 《PloS one》2009,4(10)