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Described System (described + system)
Selected AbstractsQuantitative study of bite force during sleep associated bruxismJOURNAL OF ORAL REHABILITATION, Issue 5 2001K. Nishigawa Nocturnal bite force during sleep associated bruxism was measured in 10 subjects. Hard acrylic dental appliances were fabricated for the upper and lower dentitions of each subject. Miniature strain-gauge transducers were mounted to the upper dental appliance at the right and left first molar regions. In addition, thin metal plates that contact the strain-gauge transducers were attached to the lower dental appliance. After a 1-week familiarization with the appliances, nocturnal bite force was measured for three nights at the home of each subject. From the 30 recordings, 499 bruxism events that met the definition criteria were selected. The above described system was also used to measure the maximum voluntary bite forces during the daytime. The mean amplitude of detected bruxism events was 22·5 kgf (s.d. 13·0 kgf) and the mean duration was 7·1 s (s.d. 5·3 s). The highest amplitude of nocturnal bite force in individual subjects was 42·3 kgf (15·6,81·2 kgf). Maximum voluntary bite force during the daytime was 79·0 kgf (51·8,99·7 kgf) and the mean ratio of nocturnal/daytime maximum bite force was 53·1% (17·3,111·6%). These data indicate that nocturnal bite force during bruxism can exceed the amplitude of maximum voluntary bite force during the daytime. [source] Detection of Mollicutes in bioreactor samples by real-time transcription-mediated amplificationLETTERS IN APPLIED MICROBIOLOGY, Issue 6 2010S. Laborde Abstract Aim:, Contamination by Mollicutes is a significant challenge for research laboratories and biopharmaceutical industry. It leads to alteration of results or production quality as well as loss of time, materials and revenue. These organisms can czoriginate from mammalian, avian, insect, plant or fish cells. Culture-based methods may require 28 days to detect Mollicutes. Traditional microbiology could advantageously be replaced by nucleic acid testing for earlier detection. Methods and Results:, A membrane filtration-based concentration of the Mollicutes has been coupled to real-time transcription-mediated amplification (real-time TMA) to demonstrate these advantages. The eight species required by European Pharmacopoeia have been tested and were detected with sensitivity below 100 CFU per 20-ml sample. Co-culture experiments, in which Mollicutes are grown with CHO-S (suspension) or HEK 293 (adherent) cells, were also performed to respectively mimic a bioreactor or flask contamination. Despite the fact that Mollicutes can attach to or invade mammalian cells, they were consistently detected over multiple days. Conclusions:, the sample preparation and amplification method used in this study increases sensitivity and reduces time-to-result for detection of Mollicutes. Significance and Impact of the Study:, the described system allows real-time monitoring for microbial contamination of cell-based processes and products for the biopharmaceutical industry. [source] Determining acetylcholinesterase inhibitory activity in plant extracts using a fluorimetric flow assayPHYTOCHEMICAL ANALYSIS, Issue 3 2003In Kyung Rhee Abstract A fluorometric assay for acetylcholinesterase inhibitory activity was developed in a flow system using the fluorogenic substrate 7-acetoxy-1-methyl quinolinium iodide which is hydrolysed to the highly fluorescent 7-hydroxy-1-methyl quinolinium iodide. The detection limit of galanthamine is 0.5,µM, which is about 20 times more sensitive than in the colorimetric flow assay. In the presence of 30% methanol or of 5% acetonitrile, about 70% of the enzyme activity could still be detected. Various plant extracts have been screened using the described system including bulbs of Galanthus nivalis, Eucharis amazonica (E. × grandiflora), Crinum powelli and Nerine bowdenii (all members of the Amaryllidaceae), which showed strong AchE inhibitory activity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Antimicrobial peptide interactions with silica bead supported bilayers and E. coli: buforin II, magainin II, and arenicin,JOURNAL OF PEPTIDE SCIENCE, Issue 8 2009Ryan W. Davis Abstract Using the unique quantitative capabilities of hyperspectral confocal microscopy combined with multivariate curve resolution, a comparative approach was employed to gain a deeper understanding of the different types of interactions of antimicrobial peptides (AMPs) with biological membranes and cellular compartments. This approach allowed direct comparison of the dynamics and local effects of buforin II, magainin II, and arenicin with nanoporous silica bead supported bilayers and living E. coli. Correlating between experiments and comparing these responses have yielded several important discoveries for pursuing the underlying biophysics of bacteriocidal specificity and the connection between structure and function in various cellular environments. First, a novel fluorescence method for direct comparison of a model and living system is demonstrated by utilizing the membrane partitioning and environmental sensitivity of propidium iodide. Second, measurements are presented comparing the temporal dynamics and local equilibrium concentrations of the different antimicrobial agents in the membrane and internal matrix of the described systems. Finally, we discuss how the data lead to a deeper understanding of the roles of membrane penetration and permeabilization in the action of these AMPs. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. [source] | ||||||||||