ABSTRACT
Ultrasound stimulation of living tissues is a promising technique that can be safely applied for regenerative treatments. However, the ultrasound-induced mechanotransduction is still not well understood because of the large number of parameters involved at different scales and their difficult experimental accessibility. In this context, in-vitro studies may help to gain insight into the interaction between ultrasound and cells. Nevertheless, to conduct a reliable analysis of ultrasound effects on cell culture, the monitoring of the acoustic intensity delivered to the cells is of prime interest. Thanks to the development of an innovative custom experimental set-up inspired from ultrasound stimulation of bone regeneration conditions, major disturbing phenomena such as multiple reflections and standing wave formation inside the Petri dish are eliminated. Thus, the level of ultrasound stimulation, especially, in terms of spatial average temporal average intensity (ISATA), delivered to the cells can be monitored. Then, to properly estimate the level of ultrasound stimulation, a finite element model representing the experimental in-vitro configuration is developed. The numerical model manages on capturing the characteristics of the experimentally measured acoustic intensity distribution as illustrated by the experimental and numerical ISATA values of 42.3 and 45.8 mW/cm2 respectively, i.e. a relative difference of 8%. The numerical model would therefore allow exploring data inaccessible to experimental measurement and parametric studies to be carried out and facilitates the investigation of different virtual experimental configurations.
Subject(s)
Mechanotransduction, Cellular , Ultrasonic Therapy , Cell Culture Techniques , Sound , Ultrasonic Therapy/methods , Ultrasonic Waves , UltrasonographyABSTRACT
Herbal based remedies are used worldwide to treat psychiatric disorders. The aim of this study was to analyse the essential oil composition of Achillea Wilhemsii C. Koch (Asteraceae) and to evaluate its anxiolytic effects in the elevated plus maze (EPM) model of anxiety in rat. Gas chromatography/mass spectrometry (GC/MS) analysis of the essential oil showed that the main compounds of the oil were p-ocimen (23%), 1, 8-cineole (20.8%) and carvone (19.13%). The EPM results showed that 1 mg/kg (i.p.) of the oil significantly (P<0.05) increased the percentage of the time spent and the number of entries in the open arms of the maze while it did not change the total number of entries in the maze arms. These effects were not reversed with 2 mg/kg flumazenil and 5 mg/kg naloxone. We concluded that a minimum dose of 1 mg/kg of the oil has anxiolytic effects which are not probably mediated through GABA and opioid receptors.
ABSTRACT
An accurate and very rapid method for determination of zonisamide an antiepileptic drug, in human serum is described. The analytical procedure involves liquid-liquid extraction of the analyte and an internal standard (vanillin) from human serum by ethyl acetate as extracting solvent. Chromatographic separation was achieved using a monolithic C18 analytical column and a mixture of 0.05 M phosphate buffer containing triethylamine (1 ml/l; pH 2.7) and methanol (83:17 v/v) was used as the mobile phase. The detection wavelength was set at 240 nm. The calibration curve was linear over a concentration range of 0.015-6.4 µg/ml of zonisamide in human serum. The total run time of analysis was 3.5 min and the lower limits of detection and quantification were 0.005 and 0.015 µg/ml, respectively. The method validation was carried out in terms of specificity, sensitivity, linearity, precision, accuracy and stability. The validated method was applied in a randomised crossover bioequivalence study of two different zonisamide preparations in 24 healthy volunteers, and the assay was sensitive enough to measure drug levels up to 8 days following a single dose administration of zonisamide.