1.Characterization of 5-Enolpyruvylshikimate-3- phosphate Synthase from Sclerotinia sclerotiorum
Hanying YU ; Qian YANG ; Lin LI
Chinese Journal of Biochemistry and Molecular Biology 2006;22(4):301-307
The 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase activity of Sclerotinia sclerotiorum is one of the multifunctional enzyme AROM activities, which catalyzes a reversible conversion of shikimate 3-phosphate (S3P) and phosphoenolpyruvate (PEP) to EPSP and inorganic phosphate, and is inhibited by the herbicide glyphosate (N-phosphonomethyl glycine). AROM protein has been purified from Sclerotinia sclerotiorum and the EPSP synthase has been analyzed. The results indicated that the optimal pH and temperature of EPSP synthase were 7.2 and 30℃ respectively. The activation energy of the heat-deactivated reaction of the enzyme was found to be 69.62 kJ/mol. Both of the substrates, S3P and PEP, were showed to inhibit the reaction rate when their concentrations exceeded 1 mmol/L and 2 mmol/L respectively. The Km of 140.98 μmol/L for PEP and 139.58 μmol/L for S3P were obtained by Dalziel equation which was a steadystate kinetic equation of the enzymatic reaction with the double substrates. The kinetic pattern of the enzyme was consistent with a sequential mechanism. Inhibition of the EPSP synthase reaction by glyphosate was competitive with respect to PEP, with the Ki 0. 32 μmol/L, and noncompetitive with regard to S3P. Activation by [ K+ ] was observed in the forward reaction. The Km (PEP) was lowered by increasing [ K+ ], while the Km (S3P) changed irregularly and the Ki (PEP) was enhanced.
2.Effects of Yili dark bee propolis on oral cariogenic biofilm in vitro.
Qian YU ; Jing LIN ; Zulkarjan-Ahmat ; Jin ZHAO
West China Journal of Stomatology 2015;33(4):343-346
OBJECTIVETo evaluate the effects of Yili dark bee propolis on the main cariogenic biofilm and mechanisms.
METHODSSusceptibilities to the ethanolic extract of propolis against Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Streptococcus sanguis (S. sanguis), Actinomyces viscosus (A. viscosus), and Actinomyces naeslundii (A. naeslundii) were analyzed by crystal violet stain method to determine the minimum biofilm eradication concentration (MBEC). The biofilm was initially cultivated for 24 h. Subsequently, the propolis groups with different concentration MBEC and initial pH 7.0 were cultured for 24 h. Moreover, the pH value was measured to evaluate the acid-producing ability of the tested plaque biofilm. The effects of propolis on the insoluble extracellular polysaccharide synthesis of S. mutans biofilm were evaluated by anthrone method.
RESULTSThe MBEC of Yili propolis on S. mutans, S. sobrinus, S. sanguis, A. viscosus, and A. naeslundii were 6.25, 1.56, 3.13, 0.78, and 0.78 mg.mL-1, respectively. Propolis could decrease the ΔpH of the tested plaque biofilm, and the differences between the control and propolis groups were statistically significant (P<0.05). At MBEC, propolis could reduce the ability of S. mutans in synthesizing insoluble extracellular polysaccharides.
CONCLUSIONYili propolis demonstrate remarkable eradicative effects on the cariogenic plaque biofilm, showing inhibition of the synthesis of biofilm-produced acids and insoluble extracellular polysaccharides.
Actinomyces viscosus ; Animals ; Bees ; Biofilms ; Dental Plaque ; Propolis ; Streptococcus mutans ; Streptococcus sanguis ; Streptococcus sobrinus
3.Abnormality and significance of monocyte subsets in peripheral blood of patients with rheumatoid arthritis
Lei QIAN ; Xin LIN ; Wei CHEN ; Ming LI ; Yuehong YU
Chinese Journal of Immunology 2016;32(10):1519-1523,1531
Objective:To explore the role of peripheral blood monocyte subsets in the pathogenesis of rheumatoid arthritis (RA),we therefore decided to compare the percentage of monocyte subpopulations in peripheral blood,as well as cytokines secretion function,to that of healthy controls. Methods:22 patients with RA and 22 cases of healthy controls ( HC) were drew 3 ml fresh venous blood into a tube containing heparin. The percentage of monocyte subsets,expression of Toll-like receptor(TLR)2,HLA-DR,triggering receptor expressed on myeloid cells-1(TREM-1) on intermediate monocyte and mean fluorescence intensity(MFI) of intracellular tumor necrosis factor-α ( TNF-α) were evaluated with the methods of flow cytometry ( FCM ) . The correlation between percentage of monocyte subsets and serum cytokines was explored. Statistical significance between parametric data was determined by the students't-test. Results:Compared to HC controls, the percentages of intermediate monocytes were significant higher in RA patients [ ( 11. 7 ± 1. 6)% vs (4. 6±1. 2)%,P<0. 05],as well as the expression(MFI) of TLR2 (750. 2±110. 3 vs 526. 8±98. 6) and TREM-1 (58. 4± 12. 1 vs 40. 3±10. 2) on intermediate monocytes (P<0. 05). The expression of HLA-DR on intermediate monocytes of RA patients had no difference with HC controls (P>0. 05),while MFI of intracellular TNF-αin intermediate monocytes of RA patients were significant higher than that of HC controls (46. 3±6. 4 vs 36. 7±8. 3,P<0. 05). In addition,RA patients showed a positive correlation between the percentage of CD14highCD16+ monocytes and DAS28 scores(r=0. 538,P=0. 009),as well as the serum levels of TNF-α,IL-17 ( r=0. 471,P=0. 027;r=0. 593,P=0. 003). Conclusion:Monocyte subpopulations from RA patients are abnormally skewed toward to in-termediate monocytes which has high expression of TLR2 , TREM-1 and the function of TNF-α secretion. Therefore, intermediate monocytes may play a role in the pathophysiology of RA. By modulating polarization or blocking monocyte cell surface receptors could be a new treatment of RA.
4.The effect of Yili dark bee propolis on oral cariogenic bacteria in vitro
Qian YU ; Upur HAMLAT ; Jing LIN ; Jin ZHAO
Journal of Medical Postgraduates 2014;(12):1269-1272
Objective Searching for natural anticariogenic agent has become a focus at home and abroad.The aim of this study was to evaluate the effect of Yili dark bee propolis on the main cariogenic bacteria . Methods ①The minimum inhibitory concentration (MIC) of Yili dark bee propolis on oral common cariogenic bacteria was detected by the liquid diffusion method.②The four different con-centrations lower than MIC were used to confect culture media with pH 7.0 and the normal culture media was used as control group .The pH and the changes of pH (ΔpH) were evaluated to detect the effect of Yili dark bee propolis on acid producing ability of tested bacteria .③The effects of propolis on extracellular polysaccharides synthesis of S.mutans and A.viscosus were evaluated by anthrone method. Results①The MIC of Yili dark bee propolis on S.mutans, S.sobrinus, S.sanguis, L.acidophilus, A.viscosus and A.naeslundii were 0.78, 0.39, 1.56, 0.39, 0.2, 0.2 mg/mL, respectively.The minimum bactericidal concentrations were 1.56, 0.78, 3.125, 0.78, 0.39 and 0.39 mg/mL.②The propolis could decrease theΔpH of tested bacteria, and the differences between propolis groups and control group were statis-tically significant (P<0.05).③The propolis could reduce the ability of S.m and A.viscosus synthtic extracellular polysaccharides at MIC, and the differences were significant (P<0.05). Conclusion Yili propolis could inhibit the growth, acid producing ability and polysac-charides synthesis of the main cariogenic bacteria to some extent, and it could be deemed as a natural anticariogenic agent.
5.Effects of repetitive transcranial magnetic stimulation on the lower limbmotor functionof cerebral infarction patients
Yamei LI ; Lin HUANG ; Jing ZHANG ; Jinyan TIAN ; Qian YU
Chinese Journal of Physical Medicine and Rehabilitation 2016;38(11):839-842
Objective To explore the effects of repetitive transcranial magnetic stimulation (rTMS) on the motor function of lower limbs of patients with cerebral infarction.Methods Sixty stroke survivors with lower limb dysfunctionwere randomly assigned to an rTMS treatment group or a control group,each of 30.Both groups were given routine medication and rehabilitation treatment,while the treatment group was additionally provided with 4 weeks of rTMS treatment of the contra-lesional M1 at 1 Hz and 90% motor threshold.The Fugl-Meyer motor assessment (FMA) and maximum walking speed (MWS) were used to assess both groups before and after the treatment and 2 weeks later.Adverse reactions were also recorded.Results Before the intervention,no differences were found between the two groups.After the treatment and two weeks after that,significant improvement was observed in the average FMA and 10 m MWS of both groups,with significantly more improvement in the treatment group than among the controls.No obvious adverse reactions were observed in either group.Conclusions rTMS can improve the motor function of the affected lower limbs of stroke patients safely.
6.A comparison study on the mechanical strength of two resin cements
Haijun CHEN ; Shuxiang YU ; Lin ZHANG ; Qichun QIAN ; Fuqing NAN ; Junzhou LIN
Chinese Journal of Tissue Engineering Research 2009;13(8):1585-1588
BACKGROUND: There are many species of ceramic bonding systems supplied in market, the mechanical strength is aprerequisite condition for resin cement in clinical use.OBJECTIVE: To study the difference of mechanical strength between Panavia F resin cement and self-made resin cement,DESIGN, TIME AND SETTING: A controlled observational study was performed in the prosthesis laboratory of the FourthMilitary Medical University of Chinese PLA between May 2006 and March 2007.MATERIALS: Panavia F resin cement was sourced from KURARAY MEDICAL INC. (Japan), experimental resin cement wasproduced by College of Stomatological Medicine in the Fourth Military Medical University of Chinese PLA.METHODS: Five cylindrical compressive strength specimens at an 8-mm height and 4-mm diameter were prepared, as well as5 cylindrical diametral tensile strength specimens at a 3-mm height and 6-mm diameter. AGS-500 universal material testingmachine was applied to detect the compressive strength and diametral tensile strength.MAIN OUTCOME MEASURES: The diametral tensile strength test and compressive strength test of the specimens.RESULTS: The compressive strength of Panavia F resin cement was remarkably higher than that of experimental cement[(238.92±24.54), (149.08±12.13) M Pa, P < 0.05]. There were no significances between two resin cements on diametral tensilestrength (P> 0.05).CONCLUSION: There were no significance between two resin cements on diametral tensile strength following completecuring. The compressive strength of experimental resin cement can reach the standard of ADA (> 70 MPa) although it is lowerthan the compressive strength of Panavia F resin cement.
7.Methylation status of promoter of mismatch repair genes hMLH1 and hMSH2 in epithelial ovarian cancer
Shi-Qian ZHANG ; Ai-Feng ZHANG ; Lin-Lin ZHANG ; Le-Le FU ; Hao YU ;
Chinese Journal of Laboratory Medicine 2000;0(06):-
Objective To explore the methylation status of hMLH1 and hMSH2 promoter region in the epithelial ovarian cancer and its role in oncogenesis.Methods Methylation status of hMLH1 and hMSH2 promoter region was assayed in 20 normal ovarian tissues,25 benign epithelial tumor,56 malignant epithelial tumor and cell lines SKOV3,3AO by methylation-specific PCR (MSP).SKOV3 and 3AO were analyzed before and after 5-aza-2′-deoxycytidine (5-Aza-CdR) treatment.In addition,an alterations of mRNA expression of hMLH1 and hMSH2 was observed by reverse transcription polymerase chain reaction (PT-PCR).Results No methylation of hMLH1 and hMSH2 promoter was found in normal ovarian tissues. CPG islands methylation of hMLH1 and hMSH2 was observed in 4% (1/25),8% (2/25) respectively in benign epithelial tumor,30.4% (17/56),51.8% (29/56) respectively in malignant epithelial tumor. Methylation status in promoter showed obvious correlation with pathological grade and lymph node metastasis (P
9.Endovascular treatment for severe Takayasu's arteritis
Hong JIANG ; Jun QIAN ; Hao YAN ; Peiyan DUAN ; Lin QIAO ; Hui CHEN ; Guangchao YU
Chinese Journal of General Surgery 2011;26(10):841-844
ObjectiveTo evaluate the clinical application of endovascular treatment for severe Takayasu's arteritis (TA).MethodsIn this study,35 target lesions in 32 patients [28 women,mean age (30 ±8) years] with severe Takayasu's arteritis were treated with endovascular merthod.The average length of lesion was 3.1 cm( range 2.7 -5.3).The overall average degree of diameter stenosis was 90% ± 11% (range 70- 100)in which 15 lesions were completely occlusive.There were 10 patients whose ESR were higher than 20 mm/h( range 25 -37).Follow-up included physical examination and patency evaluated by color duplex souography/computed tomography angiography/angiography at 6 months and then annually.ResultsRecanalization was unsuccessful in 3 completely occlusive lesions,with a successful rate of 80%(12/15).There was one case in which embolization leading to acute thrombogenesis developed during interventional procedure and resulting in severe stroke.The technical successful rate ( residual stenosis < 50% ) was 88.6% ( 31/35 ).The transient cerebral ischemia attack ( TIA ) symptoms disappeared in 31 cases.26 cases were followed up for an average of (19 ± 10) months (range 13 -40).Occipital infarction following severe in-stent restenosis developed 13 months later in one case.Symptomatic in-stent restenosis18monthslaterwasfoundin2cases. Patencyratewas88.5%( 23/26 ).ConclusionsEndovascular treatment is safe and effective for severe TA.Strict indication and accurate targeting the lesions help ensure the success of management.
10.Assessment of indocyanine green clearance test combined with the model for end-stage liver disease in the prediction of short-term prognosis for liver failure
Hongling FENG ; Qian LI ; Lin WANG ; Wanyou YU ; Guiyu YUAN ; Wukui CAO ; Jiming YANG
Chinese Journal of Infectious Diseases 2013;31(10):593-597
Objective To investigate the efficacy of the indocyanine green (ICG) clearance test (ICGR15) combined with the model for end-stage liver disease (MELD) for assessing the short-term prognosis of patients with liver failure.Methods Eighty patients with liver failure were analyzed retrospectively.ICGR15 and relevant clinical data within 24 hours of diagnosis were analyzed.Meanwhile,the MELD score and King's College Hospital (KCH) were evaluated.All findings were tested for correlation with 3-month mortality.Quantitative data were analyzed with analysis of variance and Student's t-test.Count data were analyzed with chi-square test.Correlation analysis was performed with Pearson's coefficient test.Results Among 80 patients with liver failure,39 patients survived and 41 died.The mortality rate of all patients was 51.2%.The serum total bilirubin,creainine concentrations,ICGR15,MELD scores and patient number in accordance with KCH criteria of surviving patients were (288.0±109.1) μmol/L,(63.3±24.4) μmol/L,(48.1±10.2)%,20.6±4.4,and 6 cases,respectively,which were lower than those in dead patients [(340.7 ± 108.2) μmol/L,(98.8 ± 59.1) μmol/L,(60.2 ± 10.6) %,26.9 ± 7.1 and 19 cases,respectively] (P =0.033,P= 0.001,P= 0.000,P= 0.000 and P =0.003,respectively).There was no significant difference of ICGR15 among four types of liver failure.A positive correlation was observed between ICGR15 and MELD score (r=0.289,P=0.009).The ICGR15-MELD model was created by subjecting ICGR15 and MELD scores to Logistic regression analysis.The following ICGR15-MELD model,Logit (P) =0.105 × ICGR15 + 0.178 × MELD score-9.734,was constructed by Logistic regression analysis.The area under the receiver operating characteristic (ROC) curve was 0.860 and the cut offpoint of 0.3 had sensitivity of 85.40% and specificity of 74.40%.The area under the curve of the ICGR15-MELD model was significantly higher than those of ICGR15 (0.791),MELD score (0.770) and KCH criteria (0.655).Conclusions ICGR15 and MELD scores perform better than the KCH criteria in predicting the prognosis of liver failure.The ICGR15-MELD model is superior to ICGR15,MELD score,and KCH in predicting the short term prognosis of patients with liver failure.