Résumé
The most effective sequence of small interfering RNA (siRNA) silencing STAT3 of psoriatic keratinocytes (KCs) was screened out,and the effects of the most effective siRNA combined with ultrasonic irradiation and SonoVue microbubbles on the expression of STAT3 of KCs and the dose-and time-response were investigated.Three chemically-synthetic siRNAs targeting STAT3 carried by Lipofectamine 3000 were transfected into KCs,and the effects on STAT3 expression were detected,then the most effective siRNA was selected for the subsequent experiments.The negative controls of siRNA (siRNA-NC) labeled with Cy3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles were transfected into KCs,then the optimal parameters of ultrasonic irradiation were determined.The most effective siRNA carried by Lipofectamine 3000 combined with ultrasonic irradiation at the optimal parameters and SonoVue microbubbles was transfected into KCs,and the dose-and time-response of RNA interference was determined.The effect of RNA interference by the most effective siRNA at the optimal time and dose carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles (LUS group) was compared with that only carried by Lipofectamine 3000 (L group).The results showed that siRNA-3 achieved the highest silencing efficacy.0.5 W/cm2 and 30 s were selected as the parameters of ultrasonic irradiation.The siRNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue mierobubbles could effectively knock down the STAT3 expression at mRNA and protein levels in dose-and time-dependent manners determined at 100 nmol/L with maximum downregulation on mRNA at 48 h,and on protein at 72 h after transfection.The LUS group achieved the highest silencing efficacy.It was concluded that siRNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles could effectively knock down the STAT3 expression in psoriatic KCs,and the optimized transfection condition and the sequence of siRNA-3 could serve for further research on gene therapy of psoriasis.
Résumé
Objective To study the effect of ultrasound-mediated microbubble on the concentration of cefuroxime in rat prostate. Methods Twenty male SD rats were randomly divided into the experimental group ( ultrasound-mediated microbubble+cefuroxime group) and the control group ( cefuroxime group) . The experimental group was given cefuroxime and microbubble via the tail vein, and then the prostates were exposed to ultrasonic irradiation for five minutes. The control group was given cefuroxime and the same amount of normal salin via the tail vein, and then given sham ultrasonic irradiation for five minutes. After the prostate was taken, cefuroxime concentration in pros-tate was measured by high performance liquid chromatograph. Results Concentration of cefuroxime in the experimental and the control group were (16. 274 ± 9. 515) μg/mg and (8. 336 ± 6. 743) μg/mg respectively. Compared to the control group, the concentration of cefuroxime was significant higher in the experimental group, and the difference is statistically significant (P <0. 05). Conclusion Low-dose ultra-sound-mediated microbubble can significantly improve the permeability of rat prostate tissue, thereby enhancing the drug concentration in prostate tissue.
Résumé
Using Chl a removal rate as index, a 28 kHz/900w ultrasonic cleaning machine was applied to testify algal removal by ultrasonic irradiation from raw water of a pool, where Microcystis aeruginosa colonies is absolutely dominated with temperature being over 20oC, and the irradiation lasted for 5 min. PAC was used as flocculant at the dose of 60 mgl-1, jar tests were done to investigate the Chl a removal by flocculation. The results showed that ultrasound raised the water temperature instantly but did not lead to a regular pH change pattern in all the treated samples. Ultrasound could remove more than 90% of Chl a from raw water with temperature over 31oC, but less than 20% of Chl a or even increased Chl a concentration in some samples with temperature lower than 31 oC. Compared with the algal removal effects by direct raw water flocculation with PAC, ultrasound did not enhance markedly the flocculation effects on algae removal, which was not in agreement with the findings reported. The reason might be due to morphology and characteristics of natural algae differed greatly from that of algae cultured in laboratory.
Résumé
The dissolution of substrate is the key step in steroid microbial conversion.The formation of surfactant micelle with a hydrophobic center directly results in increased pseudo-water-solubilities of hydrophobic compounds such as steroids.Results showed increased water solubility of steroid with the increased surfactant concentrations.Compared to mono-surfactant PSE,less quantity of multiple surfactants PSE-MGE was required to achieve the enhancement of steroid solubility at the same level,thus the negative effects of surfactants on mycelial growth were reduced and steroid conversion was therefore improved more.It was also shown that the surfactants and ultrasonic irradiation used jointly could result in better substrate dispersion and dissolution than surfactants used alone,and the best result was obtained when the comparatively high intensity (12.4 W/cm 2) and short time (5min) of ultrasonic irradiation were performed.