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Nina Vyas Kawa Manmi Qianxi Wang Ananda J. Jadhav Mostafa Barigou Rachel L. Sammons Sarah A. Kuehne A. Damien Walmsley 《Ultrasound in medicine & biology》2019,45(5):1044-1055
Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces. 相似文献
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Franck Brulle Fabien Bernard Franck Vandenbulcke Damien Cuny Sylvain Dumez 《Ecotoxicology (London, England)》2014,23(3):459-471
Real-time quantitative PCR is nowadays a standard method to study gene expression variations in various samples and experimental conditions. However, to interpret results accurately, data normalization with appropriate reference genes appears to be crucial. The present study describes the identification and the validation of suitable reference genes in Brassica oleracea leaves. Expression stability of eight candidates was tested following drought and cold abiotic stresses by using three different softwares (BestKeeper, NormFinder and geNorm). Four genes (BolC.TUB6, BolC.SAND1, BolC.UBQ2 and BolC.TBP1) emerged as the most stable across the tested conditions. Further gene expression analysis of a drought- and a cold-responsive gene (BolC.DREB2A and BolC.ELIP, respectively), confirmed the stability and the reliability of the identified reference genes when used for normalization in the leaves of B. oleracea. These four genes were finally tested upon a benzene exposure and all appeared to be useful reference genes along this toxicological condition. These results provide a good starting point for future studies involving gene expression measurement on leaves of B. oleracea exposed to environmental modifications. 相似文献
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Delphine Payros Thomas Secher Michèle Boury Camille Brehin Sandrine Ménard Christel Salvador-Cartier Gabriel Cuevas-Ramos Claude Watrin Ingrid Marcq Jean-Philippe Nougayrède Damien Dubois Antoine Bedu Fabien Garnier Olivier Clermont Erick Denamur Pascale Plaisancié Vassilia Theodorou Jean Fioramonti Ma?wenn Olier Eric Oswald 《Gut microbes》2014,5(3):313-325
The neonatal gut is rapidly colonized by a newly dominant group of commensal Escherichia coli strains among which a large proportion produces a genotoxin called colibactin. In order to analyze the short- and long-term effects resulting from such evolution, we developed a rat model mimicking the natural transmission of E. coli from mothers to neonates. Genotoxic and non-genotoxic E. coli strains were equally transmitted to the offspring and stably colonized the gut across generations. DNA damage was only detected in neonates colonized with genotoxic E. coli strains. Signs of genotoxic stress such as anaphase bridges, higher occurrence of crypt fission and accelerated renewal of the mature epithelium were detected at adulthood. In addition, we observed alterations of secretory cell populations and gut epithelial barrier. Our findings illustrate how critical is the genotype of E. coli strains acquired at birth for gut homeostasis at adulthood. 相似文献
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Kaluzay J Vandenberghe K Fontaine D Ganame J Anné W Van der Merwe N Van de Werf F Heidbüchel H 《International journal of cardiology》2005,98(3):431-437
BACKGROUND: Determination of ST-segment deviation (STdev) and its resolution (STR) by reperfusion strategies have become important tools in the assessment of patients with acute myocardial infarction (AMI). STdev has been measured at different time-points, i.e. at 20-80 ms after the J-point. There are no data comparing STR at different time-points. METHODS AND RESULTS: STdev was measured using a new computer-assisted workflow. The intraclass correlation coefficients (ICC) for validity and agreement vs. classical manual measurements (n=1020) were both 0.996 (p<0.0001). The reliability indices were 0.991 (95% CI 0.990-0.992) for the manual vs. 0.995 (95% CI 0.995-0.996) for the computer-assisted method, indicating superiority of the latter. 12-lead STdev were determined on ECGs before (baseline) and 180 min after start of thrombolytic therapy, measured both at the J-point (STdev(J)) and 20 ms after the J-point (STdev(J20); n=2400). STdev(J20) was on average 0.01+/-0.03 mV higher than STdev(J) (p<0.0001) with a tendency towards larger differences for higher ST-elevations (p<0.001). Although the average STR calculated from STdev(J20) and STdev(J) was not statistically different in any infarct location group, in 26% of the patients the difference was >10%, and 11% of the patients were classified into another ST-resolution group. Analysing STdev only in the single lead with the highest ST-elevation at baseline (a simplified measurement which may eliminate the confounding effect of ST-depressions) showed an even higher classification discordance (14% of the patients). CONCLUSIONS: The time-point of STdev measurement is an important variable to be accounted for when evaluating ST resolution data. Uncontrolled extrapolation of classification schemes based on STdev(J20) to other time-points cannot be justified. 相似文献