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Objective@#To investigate the effect and regulatory mechanism of Smurf2 on the negative regulator Smad7 of TGF-β1/Smad signaling pathway in hypertrophic scar fibroblasts.@*Methods@#From January to October 2014, 8 patients with hypertrophic scar after burn were admitted. The age of patients ranged from 1 year 8 months to 7 years, and the time of scar hyperplasia ranged from 2 to 12 months. The residual normal skin of the same patient was used as the control. The fibroblasts were isolated from hypertrophic scar and normal skin respectively and cultured. The third to fifth passage cells were used for the experiments. ① The protein expression of Smad7 in the two groups was detected by Western Blot. ② Hypertrophic scar fibroblasts and normal skin fibroblasts were treated with exogenous TGF-β1 at concentration of 10 ng/ml for 0 min, 5 min, 15 min, 30 min, 1 h, 2 h and 12 h. The expression of Smad7 protein and mRNA were detected by Western Blot and RT-PCR, respectively. ③ The cell lysates of the two groups were collected and incubated with the ubiquitin mixture for 1 h, 2 h and 6 h at 37℃, respectively. The degradation level of Smad7 protein was detected by Western Blot. ④ The cell lysate of hypertrophic scar fibroblasts was collected and incubated with ubiquitin mixture with or without proteasome inhibitor (MG132: MG115=1: 1) to study its inhibitory effect on the degradation of Smad7 in vitro. ⑤ Immunoprecipitation (IP) technique was used to detect the interaction between Smad 7 and E3 ubiquitin ligase Smurf2 in hypertrophic scar fibroblasts. ⑥ The expression of Smad7 protein in hypertrophic scar fibroblasts stimulated by TGF-β1 after Smurf2 silencing by small interference RNA (siRNA) technique were detected by Western blot.@*Results@#① There was no significant difference in the expression level of Smad7 protein between hypertrophic scar and normal skin fibroblasts(t=0.76, P=0.46). ② Expressions of Smad7 mRNA and protein in normal skin fibroblasts stimulated by exogenous TGF-β1 gradually increased in a time-dependent manner(P<0.05). The expression of Smad7 mRNA in the hypertrophic scar fibroblasts increased at all-time points except at 5min , (P<0.05), while there was no significant difference in the expression level of Smad7 protein at all-time points with or without TGF-β1 stimulation(P>0.05). ③ Degradation of Smad7 protein was enhanced in hypertrophic scar fibroblasts (the expression level of Smad 7 protein at each time point was compared with that of the control group and the last time point, P<0.05), while there was no significant difference in Smad7 protein degradation in normal skin fibroblasts(P=0.162). ④ Enhanced degradation of Smad7 in hypertrophic scar fibroblasts was blocked by the addition of the proteasome inhibitors MG132/MG115. ⑤ In hypertrophic scar fibroblasts, the Smurf2-Smad7 complex was detected, which indicated the interaction between Smurf2 and Smad7 in hypertrophic scar fibroblasts. ⑥ The expression of Smad7 protein was not increased in the hypertrophic scar fibroblasts stimulated by TGF-β1, whereas the stimulation of TGF-β1 increased the expression of Smad7 protein after silencing of Smurf2 gene expression.@*Conclusions@#In the hypertrophic scar fibroblasts, Smurf 2 attenuates the inhibitory effect of Smad 7 on TGF-β1 signaling pathway through the degradation of Smad7 by ubiquitination, which may be involved in the formation of hypertrophic scar.
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Population pharmacokinetics of vancomycin (VAN) in the Chinese patients was described by using nonlinear mixed-effects modeling (NONMEM). 619 VAN serum concentrations data from 260 patients including 177 males and 83 females were collected separately from two centers. A one-compartment model was used to describe this sparse data. No significant difference was observed between two center datasets by introducing SID covariate. The final model was as CL= (θ (base0+ θ(max) x(1 -e(-θ(Age)(Age/72) and V = θ x θ (Age)(Age/72). The creatinine clearance (CL(Cr)) and Age were identified as the most significant covariate in the final model. Typical values of clearance (CL) and volume of distribution (V) in the final model were 2.91 L x h(-1) and 54.76 L, respectively. Internal model validation by Bootstrap and NPDE were performed to evaluate the robustness and prediction of the final model. The median and 95% confidence intervals for the final model parameters were based on 1000 Bootstraps. External model evaluation was conducted using an independent dataset that consisted of 34 patients to predict model performance. Pharmacodynamic assessment for VAN by AUC (0-24 h) to MIC ratios of over 400 was considered to be the best to predict treatment outcomes for patients. AUC (0-24 h) was calculated by clearance based on the above population model. The results indicate that the conventional dosing regimen probably being suboptimal concentrations in aged patients. The approach via population pharmacokinetic of VAN combined with the relationship of MIC, Age, CL(Cr) and AUC(0-24 h)/MIC can predict the rational dose for attaining efficacy.
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Purpose To study the polysaccharide from Pinus massoniana pollen(PPM)and to compare its anti-tumor,immune modulation activities and scavenging qualities of free radical with its sulfated derivative(S-PPM).Methods PPM Wag chemically modified by chlorosulfonic acid-pyfidine method and their bioactivities were compared.Results The substituting degree of S-PPM was 1.47.Results showed that S-PPM was more powerful in inhibiting the growth of tumor cell in vivo and in vitro and in promoting T,B lymphocytes than PPM.But there Wag no remarkable difference in promoting phagocytosis of macmphages.S-PPM was stronger in scavenging superoxide anion radical than PPM but it wag vice versa in scavenging hydroxyl radical.Conclusion S-PPM inhibited the cancer cell growth mainly through specific immunity.Sulfate of PPM influenced its quality of scavenging free radicals greatly.
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OBJECTIVE:To evaluate1812cases of therapeutic drug monitoring(TDM)and the clinical drug utilization of cyclosporine.METHODS:Analysis and statistics of cyclosporine TDM data of1812cases(502subjects)in our hospital were carried out.RESULTS:Among all the1st TDM concentration,only41.4%was within the therapeutic window.Constituent ratios of patients whose drug concentration were monitored once,twice,or three times respectively was44.8%,16.3%and11.6%respectively.Among all the subjects undergoing3～4times of TDM,constituent ratio of patients whose drug con-centrations of the1st,2nd,3rd and4th TDM are within therapeutic window are40.6%,48.0%,50.0%and57.9%respec-tively.CONCLUSION:Although TDM is widely used,for some reasons,the constituent ratio of drug concentration within therapeutic window is low and the TDM times are much less than enough.Even TDM is multiple,the status of is not satisfac-tory,So clinics should pay more attention to the phenomenon that the patients’medication can’t be adjusted properly;Mean-while,it correlates with the expensive medication costs,etc.