Objective To estimate the effect of tretinoin gel sheeting on early-stage hyperplastic scars in rabbit ears,and to evaluate the feasibility to prevent and treat hyperplastic scars with it.Methods The ears of 24 rabbits were used to establish a model of hyperplastic scar according to previously reported methods.Then,the rabbit ears were randomly divided into four groups:control group receiving no treatment,gel sheeting group treated with the vehicle of the tretinoin gel sheeting,0.05％ tretinoin group treated with 0.05％ tretinoin gel sheeting,0.1％ tretinoin group treated with 0.1％ tretinoin gel sheeting.All the gel sheetings were topically used twice daily for six consecutive weeks.During the treatment,the size,thickness,color and texture of scars were estimated.After six weeks of treatment,all the scar tissues were resected from the rabbit ears and subjected to hematoxylin and eosin (HE) staining and van Gieson (VG) staining.Statistical analysis was carried out by analysis of variance and rank sum test.Results The scars were deeply colored,thickened,hard and elevated with an uneven surface in the control group,but lightly colored,thinned and soft with the presence of small subcutaneous nodules in the other three groups.The surface of scars in the two tretinoin groups was similar to that of adjacent normal skin,and scaling was observed on the scar surface in the 0.1％ tretinoin group.HE and VG staining showed a disarrangement of collagen fibers with the formation of vortex-like structures in the control group.A significant decrease was noted in the number of fibroblasts and microvessels as well as amount of collagen deposition per unit cross-sectional area in the two tretinoin groups compared with the control group and gel sheeting group.Additionally,the collagen fibers were regularly arranged and parallel to the long axis of scars in the two tretinoin groups.The scar hyperplasia index (HI) was 3.173 ± 0.26,2.465 ± 0.19,1.906 ± 0.21 and 1.903 ± 0.23 in the control group,gel sheeting group,0.05％ tretinoin group and 0.1％ tretinoin group respectively,the fibroblast density (NA) was 5836.7 ± 527.03,4128.73 ± 387.66,3207.59 ± 439.17 and 3200.28 ± 421.48 respectively,and the area density of collagen fiber (AA) was 45.38 ± 5.83,36.57 ± 6.84,28.09 ± 3.82 and 28.07 ± 3.47 respectively.As far as HI,NA and AA were concerned,the control group differed significantly from the other three groups (all P ＜ 0.01),and the gel sheeting group from the two tretinoin groups (all P ＜ 0.01),but no significant difference was observed between the two tretinoin groups (all P ＞ 0.05).Conclusions Topical tretinoin gel sheeting can inhibit scar proliferation at early stage in rabbit ears,and may provide a new choice for the prevention and treatment of hyperplastic scars.

Objective To compare the clinical efficacy,adverse reactions,and management effect of postoperative intravenous analgesia for patients with postoperative intravenous analgesia with digital information technology and electronic analgesia pump system.Methods Totally 100 patients with postoperative intravenous analgesia (PCIA) were selected from April 2015 to September 2015 with postoperative intravenous analgesia and randomly divided into Wireless analgesic pump system Group (A group) and electronic analgesia pump group (group B),n =50 each group.Pain score (NRS),sedation score (OAA/S),comfort score (BCS),the total number of times and the number of effective press were pressed in patients were observed and compared between two groups after postoperative analgesia 1 hour (T0),4 hour (T1),10 hour (T2),16 hour (T3),and 24 hour (T4).Patients with early adverse reactions,patients and ward medical staff satisfaction,pain pump failure found in the medical staff and effective treatment of adverse events were also observed and compared in two groups.Results There were no significant difference of patients with NRS,OAA/S and BCS in two groups (P ＞ 0.05).Adverse reactions after postoperative analgesia,total number of times and the number of effective press had also no significant difference in two groups (P ＞ 0.05).Two groups of patients with air blockage,incomplete analgesia rate of adverse events was not significantly different (P ＞ 0.05).Medical workers in time [(1.0 ± 0.5) min vs (3.0 ± 2.1) min,P ＜ 0.05],effective processing time [(4.0-± 2.1) min vs (8.0 ± 5.1) min,P ＜ 0.05] in group A was significantly shorter than group B.The patient satisfaction in group A was significantly higher than group B(12.0 ± 4.2 vs 9.0 ± 3.1,P ＜ 0.05).The satisfaction degree of medical staff in group A was also significantly higher than group B(13.0 ±3.1 vs 10.0 ±2.1,P ＜0.05).Conclusions The digital information technology of wireless analgesic pump is applied to postoperative analgesia for medical workers to standardize management,improve the work efficiency,and increase the satisfaction of patients and medical staffs.

Objective To establish a UPLC-MS/MS method for the determination of dexmedetomidine in human plasma and investigate the effect of obstructive jaundice on pharmacokinetics of dexmedetomidine in vivo. Methods Samples were obtained by liquid-liquid extraction. Agilent Eclipse Plus C₁₈ column was used for chromatograph with methanol and 0.1% formic acid-water solution as mobile phase. Flow rate was 0.2 ml/min. The column temperature was 35 ℃, and the MS detection was selected in MRM mode. Results The calibration curves of dexmedetomidine showed good linearity in the ranges of 0.01−10.00 ng/ml. The results of intra and inter-day precisions were both within 15%. The recovery rate was 85.5%−93.1%. Matrix effect was 91.2%−95.6%. Samples remained stable during analysis. Compared with the control group, c_max、AUC_(0−t)、AUC_(0−∞) and V_z of dexmedetomidine in the patients with obstructive jaundice were increased by 63.4%, 78.9, 66.4%, 82.5%, respectively (P<0.01). CLz was decreased by 42.1%. Conclusion This method is accurate, sensitive and reproducible. It is suitable for dexmedetomidine assay in human plasma. The elimination rate of dexmedetomidine is slower in obstructive jaundice.