OBJECTIVE: As a medicinal plant, the resource of Rhodiola dumulosa is deficient along with the large collection. For the protection and utilization of R. dumulosa, the influence of plant growth regulators (PGRs) on callus induction and adventitious shoots differentiation, polysaccharide production and the antioxidant activity were tested. METHODS: Internodes of R. dumulosa were used as explants and cultured on MS medium plus different plant growth regulators (PGRs). The anti-oxidative activities of polysaccharides were evaluated using radical scavenging assays. RESULTS: By response surface plot, 0.85 mg/L N6-benzyladenine (BA), 0.34 mg/L naphthaleneacetic acid (NAA) and 0.33 mg/L 2,4-dicholorophenoxyacetic acid (2,4-D) were the optimal factors for callus induction (90.03%) from internodes explants on MS medium. The fresh weight of green callus increased 47.26 fold, when callus was inoculated on MS + thidiazuron (TDZ) 0.5 mg/L + NAA 2.0 mg/L. Adventitious buds regenerated from callus on the media of MS were fortified with BA 1.0 mg/L plus NAA 0.5 mg/L, and the induction rate was 40.00%. MS plus indole-3-butyric acid (IBA) 1.0 mg/L produced the highest rooting rate with 10 to 15 roots in a length of 2-3 cm per shoot. The content of total polysaccharides in callus developed on MS + TDZ 0.5 mg/L + NAA 2.0 mg/L and MS + BA 1.0 mg/L + NAA 0.5 mg/L was as high as 1.72%-2.15%. At the dose of 0.5 mg/mL polysaccharides extracted from different callus induced on MS + NAA 2.0 mg/L + TDZ 0.5 mg/L or MS + BA 1.0 mg/L + NAA 0.5 mg/L or MS + BA 0.5 mg/L + 2,4-D 0.5 mg/L, the ABTS radical eliminating percentages were 82.78%, 80.18% and 68.59%, respectively, much higher than that of wild plant. CONCLUSION A rapid micropropagation system for R. dumulosa has been developed. The combination of TDZ and NAA or BA and NAA can increase the yield of the total polysaccharides. The polysaccharides isolated from callus and whole wild plants had stronger free radicals scavenging activities, indicating that polysaccharides from R. dumulosa are the potential pharmaceutical supplements.

Malaria still threatens global health seriously today. While the current discoveries of antimalarials are almost totally focused on single mode-of-action inhibitors, multi-targeting inhibitors are highly desired to overcome the increasingly serious drug resistance. Here, we performed a structure-based drug design on mitochondrial respiratory chain of

Objective To compare the efficacy,safety and cost between ultrasound-guided percutaneous microwave ablation and surgical resection in patients with papillary thyroid microcarcinoma.Methods A total of 89 patients highly suspected papillary thyroid microcarcinoma by cervical ultrasonography were proved by ultrasound guided fine-needle aspiration biopsy in The Second Affiliated Hospital of Zhejiang University School of Medicine from January 2014 to February 2017.Totally 49 patients underwent microwave ablation(microwave group)while 40 patients underwent surgical resection(surgical group).T test was used to compare operation time,hospitalization expenses and the hospitalization time between the microwave group and the surgical group.Chi-squared test was applied to compare complications rate between the two groups.T test was used to compare the level of thyroid-related hormone before and after operation in the two groups.Results In the microwave group,the operation time,the hospitalization expenses and the hospitalization time were less [(55.85±5.05)min vs(25.73±9.46)min,(25435.91±5763.35)CNY vs(11307.48±3884.62)CNY and(6.78±3.03)d vs(2.92±0.78)d].These differences were statistically significant(t=-18.985,-13.084 and-7.747,P＜0.001).No severe complications occurred in the two groups.The difference of complications rate between the two groups was not statistically significant [6.1%(3/49)vs 10.0%(4/40),χ 2=-0.452,P=0.779].The level of 3'-triiodothyronine(FT3)and 4'-triiodothyronine(FT4)were higher after the operation in the microwave group,but these differences were not statistically significant.The level of FT3 and FT4 were lower [(4.5±0.50)pmol/L vs(3.90±0.72)pmol/L,(13.94±2.41)pmol/L vs(12.69±2.88)pmol/L],while the level of TSH was higher [(3.66±6.29)mIU/L vs(10.12±15.61)mIU/L] after operation in the surgical group.These differences were statistically significant(t=6.214,P＜0.001; t=2.808,P=0.008; t=-3.035,P=0.004).Conclusions Ultrasound-guided percutaneous microwave ablation is characterized by minimal invasion,good cosmetic effect,low cost and definite curative effect.It offered a new choice for the patients who refuse to undergo surgical resection.