1.Application of rapid identification for Streptpcoccus mutans, Streptpcoccus sobrinus and Streptpcoccus sanguis in the native dental plaque biofilm by fluorescence in situ hybridization
Chinese Journal of Microbiology and Immunology 2008;28(2):162-165
Objective To examine Streptpcoccus mutans,Streptpcoccus sobrinus and Streptpcoccus sanguis in the early formation of native dental plaque biofilm. Methods An experimental dental plaque biofilm model in the oral cavity was established using enamel slabs. The spatial distribution of S. mutans, S.sobrinus and S. sanguis in the early colonization of dental plaque biofilms on the enamel surface was observed bv in situ, real-time and dynamic observations and optical sections utilizing confocal laser scanning microscopy(CLSM) and fluorescence in situ hybridization(FISH). The experiment data were analyzed with One-Way AVOVA, α=0.05 using SPSS11.5. Results Dental biofilm had a certain degree of thickness and various forms in three-dimensioned structure. The bacteria in the structure were sparse at the inner layers and the outer layers. In the middle layers the bacteria were closely compacted. There were many voids traversing from the outside of the biofilm to the enamel surface. At the initial stage of dental biofilm formation, the scanned average thickness of S. mutans,S. sobrinus and S. sanguis increased with time elapsing,the mean thicknesses of 1 h biofilms were 20.43 μm,11.50 μm and 14.76 μm,respectively,and those of 24 h were the thickest in terms of average level,the mean values were 70.25 μm,75.40 μm and 79.98 μm,respectively. Conclusion The fluorescence in situ hybridization combined with CLSM are thought to be convenient and sensitive to detect S. mutans, S. sobrinus and S. sanguis in the dental plaque biofilms.
2.Comparison of the mechanical properties of composite resin cured by halogen curing light with those by LED curing light
Yakun JI ; Junqi LING ; Han CHEN
Journal of Practical Stomatology 1996;0(02):-
0.05),respectively.Conclusion:LED curing light can reach the performance level of halogen curing light and is suitable for routine oral clinical application for resin curing.
3.Identification of the related substances in docetaxel injection by LC-MS/MS.
Yakun RAO ; Meng WANG ; Li DING ; Bing LIU ; Cheng JI ; Zhengyu YAN
Acta Pharmaceutica Sinica 2012;47(6):779-84
The related substances in docetaxel injection were identified by LC-MS/MS. Ethyl acetate was used to extract the injection to remove the pharmaceutical excipients. HPLC separation was carried out on a Hedera ODS-2 column (150 mm x 2.1 mm, 5 microm) with a mobile phase consisting of acetonitrile - 0.1% acetate acid aqueous solution (40: 60). Electrospray ionization source was set in the positive mode for the LC-ESI-MS/MS, and the ion monitoring modes were full scan and product ion scan. According to the mass spectra of the related substances, the fragment profiles were explained, and the chemical structures were elucidated. Docetaxel and its main related substances were well separated. Nine related substances in docetaxel injection were detected by LC-MS/MS. Their chemical structures were proposed, and four of them were identified in the docetaxel injection for the first time. The established LC-MS/MS method is effective in the separation and identification of the related substances in docetaxel injection. The test results are useful for its quality control.
4.High uric acid induces phenotypic transition of renal tubular cells via PI3K/Akt signaling pathway
Xiaoyan XIONG ; Shoujun BAI ; Yakun WANG ; Tingting JI ; Hongxiu DU ; Xiaoying LI ; Congpu GAO ; Juan LIU ; Yingchun ZHU ; Fangfang ZHA
Chinese Journal of Nephrology 2018;34(2):130-135
Objective To investigate the effect and the mechanism of epithelial-mesenchymal transition (EMT) in renal tubular cells induced by uric acid.Methods Normal rat kidney tubular cell line (NRK-52E) were exposed to different concentrations of uric acid (100,200,400,600,800 μmol/L UA) for 48 hours to induce EMT.Morphological changes of the NRK-52E cells were examined under an inverted phase contrast microscope.The protein expression of E-cadherin,α-SMA,p-Akt and Akt were detected by Western blotting.The distribution of E-cadherin and α-SMA were detected by immunofluorescence.NRK-52E cells were pretreated by different concentrations of LY294002(0,2.5,5,10,15 μmol/L),the inhibitor of PI3K/p-Akt signaling pathway,and then processed by uric acid (400 μmol/L) for 48 hours.Western blotting was used to detect the protein expression of p-Akt and Akt.NRK-52E cells were then divided into four groups:normal group (N),uric acid group (UA),LY294002 group (LY),uric acid with LY294002 group (UA + LY).The protein expression of E-cadherin and α-SMA were detected by Western blotting,the distribution of E-cadherin,α-SMA and p-Akt were detected by immunofluorescence.Results There was abundant cellular expression of E-cadherin in unstimulated renal tubular cells whereas its expression was significantly decreased in uric acidstimulated cells (P < 0.05).In addition,uric acid induced de novo expression of α-SMA in contrast to almost negative staining in untreated cells (P < 0.05).p-Akt were obviously increased in high uric acid group (P < 0.05) and Akt changed not significantly (P > 0.05).NRK-52E cells transformed into elongated fibroblast-like cells from cuboidal clustered epithelial cells.These indicated that uric acid has induced EMT and activated PI3K/p-Akt signaling pathway in NRK-52E cells.However,the above effects of uric acid were abolished when p-Akt was blocked by the PI3K inhibitor (10,15 μmol/L LY294002),indicated that LY294002 has reversed the trend of EMT.Conclusions High uric acid induces phenotypic transition of renal tubular cells probably via activating PI3K/Akt signaling pathway.
5.Meta-analysis of the effect of physical training on physiological function of adult renal transplant recipients
Xiaoyan XIONG ; Shoujun BAI ; Yakun WANG ; Tingting JI ; Hongxiu DU ; Xiaoying LI ; Congpu GAO ; Juan LIU ; Yingchun ZHU ; Fangfang ZHA
Chinese Journal of Nephrology 2018;34(6):424-431
Objective To assess the impact of physical training on physiological function of adult renal transplant recipients by meta-analysis and to provide theoretical guidance for clinical practice.Methods Randomized controlled trials of physical training for the treatment of renal transplant recipients until October 2017 were searched in the database of Cochrane library,PubMed,Embase,Web of Science,Wanfang Data and CNKI.Data extracted from the literatures were analyzed with RevMan software (version 5.3).Results A total of 10 studies in 10 manuscripts met the inclusion criteria,and 557 cases were included.Meta-analysis results were as follows.Compared with the control group (routine drug therapy),the level of peak exercise oxygen uptake (peak VO2) was significantly increased in physical training group (routine drug therapy and physical training) (MD=2.40,95% CI 0.15-4.64,P=0.04).However,there was no statistically significant difference in the change of blood lipid,blood pressure,hemoglobin and serum creatinine between the two groups (all P >0.05).Conclusions Physical training can improve cardio respiratory fitness of renal transplant recipients in the early stage,but it has no obvious effect on blood pressure,blood lipid,hemoglobin and blood creatinine.
6.Research on mental fatigue information transmission integration mechanism based on theta-gamma phase amplitude coupling.
Shuo YANG ; Yakun JI ; Runze LI ; Lei WANG ; Guizhi XU
Journal of Biomedical Engineering 2018;35(5):672-678
Mental fatigue is a subjective fatigue state caused by long-term brain activity, which is the core of health problems among brainworkers. However, its influence on the process of brain information transmission integration is not clear. In this paper, phase amplitude coupling (PAC) between theta and gamma rhythm was used to study the electroencephalogram (EEG) data recorded before and after mental fatigue, so as to explain the effect of mental fatigue on brain information transmission mechanism. The experiment used a 4-hour professional English reading to induce brain fatigue. EEG signals of 14 male undergraduate volunteers before and after mental fatigue were recorded by Neuroscan EEG system. Phase amplitude coupling value was calculated and analyzed. test was used to compare the results between two states. The results showed that theta phase of more than 90% of the electrodes in the whole brain area jointly modulated gamma amplitude of the right central area and the right parietal area, and the coupling effect among different brain regions significantly decreased ( < 0.05) when participants had felt mental fatigue. This paper shows that phase amplitude coupling can explain the influence of mental fatigue on information transmission mechanism. It could be an important indicator for mental fatigue detection. On the other hand, the results also provide a new measure to evaluate the effect of neuromodulation in relieving mental fatigue.