Objective To explore the inhibitory effect of guggulsterone(GS)on diethylnitrosamine(DEN)-induced liver fibrosis in rats and its mechanism.Methods DEN-induced liver fibrosis model was established in SD rats.The successful model rats were randomly divided into model group(n=6),GS group(n=6,50 mg/kg,intraperitoneal injection for 4 weeks),GS+SRI group(n=6,50 mg/kg+30 mg/kg,intraperitoneal injection for 4 weeks),and control group(n=6,without DEN-induced).Rats in the control group and the model group were injected with the same amount of normal saline.The pathological changes of the liver were detected by HE staining.Serum liver function indexes including alanine aminotransferase(ALT),aspartate aminotransferase(AST),albumin(ALB)and alkaline phosphatase(ALP)were detected by automatic biochemical analyzer.The serum levels of pro-collagen Ⅲ(PC-Ⅲ),collagen Ⅳ(Ⅳ-C),hyaluronidase(HA),laminin(LN),malondialdehyde(MDA),reduced glutathione(GSH),superoxide dismutase(SOD),and catalase(CAT)were detected by ELISA assay.The mRNA and protein expression of TGF-β1,Smad2,and p-Smad3/Smad3 were detected by Real-time PCR and Western blotting.Results Compared with the control group,the model group showed typical pathological changes of liver fibrosis;the serum ALB,GSH,SOD and CAT levels were significantly decreased(P＜0.05);the serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA,LN and the mRNA expression of TGF-β1,Smad3 and protein expression of TGF-β1,p-Smad3 in liver tissues were significantly increased(P＜0.05).Compared with the model group,the pathological changes of liver fibrosis in the GS group were alleviated,and the serum levels of ALB,GSH,SOD and CAT were significantly increased(P＜0.05),the serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA and LN,the mRNA expression of TGF-β1 and Smad3,and protein expression of TGF-β1 and p-Smad3 in liver tissues were significantly decreased(P＜0.05).In addition,after the administration of SRI,TGF-β1 signaling pathway activator,compared with the GS group,the GS+SRI group showed significantly decreased serum ALB,GSH,SOD and CAT levels(P＜0.05),but significantly increased serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA and LN as well as the mRNA expression of TGF-β1 and Smad3 and protein expression of TGF-β1 and p-Smad3 in liver tissues(P＜0.05).Therefore,SRI attenuated the anti-fibrotic effect of GS on rats with liver fibrosis.Conclusion GS has certain inhibitory effect on DEN-induced liver fibrosis in rats,and its mechanism may be related to the reduction of oxidative stress level and the inhibition of the activation of TGF-β1/Smad3 signaling pathway.

Objective To explore the inhibitory effect of guggulsterone(GS)on diethylnitrosamine(DEN)-induced liver fibrosis in rats and its mechanism.Methods DEN-induced liver fibrosis model was established in SD rats.The successful model rats were randomly divided into model group(n=6),GS group(n=6,50 mg/kg,intraperitoneal injection for 4 weeks),GS+SRI group(n=6,50 mg/kg+30 mg/kg,intraperitoneal injection for 4 weeks),and control group(n=6,without DEN-induced).Rats in the control group and the model group were injected with the same amount of normal saline.The pathological changes of the liver were detected by HE staining.Serum liver function indexes including alanine aminotransferase(ALT),aspartate aminotransferase(AST),albumin(ALB)and alkaline phosphatase(ALP)were detected by automatic biochemical analyzer.The serum levels of pro-collagen Ⅲ(PC-Ⅲ),collagen Ⅳ(Ⅳ-C),hyaluronidase(HA),laminin(LN),malondialdehyde(MDA),reduced glutathione(GSH),superoxide dismutase(SOD),and catalase(CAT)were detected by ELISA assay.The mRNA and protein expression of TGF-β1,Smad2,and p-Smad3/Smad3 were detected by Real-time PCR and Western blotting.Results Compared with the control group,the model group showed typical pathological changes of liver fibrosis;the serum ALB,GSH,SOD and CAT levels were significantly decreased(P＜0.05);the serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA,LN and the mRNA expression of TGF-β1,Smad3 and protein expression of TGF-β1,p-Smad3 in liver tissues were significantly increased(P＜0.05).Compared with the model group,the pathological changes of liver fibrosis in the GS group were alleviated,and the serum levels of ALB,GSH,SOD and CAT were significantly increased(P＜0.05),the serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA and LN,the mRNA expression of TGF-β1 and Smad3,and protein expression of TGF-β1 and p-Smad3 in liver tissues were significantly decreased(P＜0.05).In addition,after the administration of SRI,TGF-β1 signaling pathway activator,compared with the GS group,the GS+SRI group showed significantly decreased serum ALB,GSH,SOD and CAT levels(P＜0.05),but significantly increased serum levels of ALT,AST,ALP,MDA,PC-Ⅲ,Ⅳ-C,HA and LN as well as the mRNA expression of TGF-β1 and Smad3 and protein expression of TGF-β1 and p-Smad3 in liver tissues(P＜0.05).Therefore,SRI attenuated the anti-fibrotic effect of GS on rats with liver fibrosis.Conclusion GS has certain inhibitory effect on DEN-induced liver fibrosis in rats,and its mechanism may be related to the reduction of oxidative stress level and the inhibition of the activation of TGF-β1/Smad3 signaling pathway.

Objective To probe into the total number and development status of respiratory physicians in China, and to analyze existing problems, for reference in making strategy and policy decisions in professional development of respiratory physicians in the country. Methods The basic information of China′s healthcare institutions and healthcare manpower in 2015 were provided by the Statistics Center of the National Health Commission. The number of respiratory specialists and their profile, drawn from such basic information, were subject to descriptive statistics. Results In 2015, there were 2.729 million medical practitioners ( including assistant doctors ) nationwide, 30.3 thousand among whom being respiratory physicians, accounting for 1.11% of the total. Among these respiratory physicians, practicing respiratory physicians account for 87.1% , respiratory physicians with a master degree and above account for only 19.7% , respiratory physicians with over 10 years of working experience account for 65.8% , respiratory physicians with senior titles account for only 21.4% , and 89.4% of the respiratory physicians work in general hospitals. Conclusions By the criteria of specializing in respiratory specialty over five years and being attending or above, the number approximates 14. 6 thousand nationwide. If practicing ( assistant) physicians specializing in respiratory specialty are also included, the number may hit 30. 3 thousand. Such a number, compared with other specialties, may be sufficient, yet their competence is far from satisfactory. Therefore it is imperative to build a standardized pulmonary medicine fellowship training system for their competence improvement.

The Au-PDA-Fe3O4 decorated graphene oxide electrode was modified with Prussion blue-secondary antibodies for determination of cancer biomarker α-fetoprotein (AFP) with great sensitivity.Scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible absorption spectrometry were used to characterize the structure of the material.Greatly enhanced sensitivity for the cancer biomarker is based on a dual signal amplification strategy.First, Fe3O4-PDA-Au used for the biosensor platform increased the surface area to capture a large amount of primary antibodies (Ab1), which resulted in amplification of the detection response.Second, graphene oxide allowed several binding events of PB-Ab2.Enhanced sensitivity was also achieved by introducing the multibioconjugates of Ab2-PB-GO onto the electrode surface through sandwich immunoreactions.The test result shows that there are linear relationships between current and AFP concentrations ranging from 0.005 ng/mL to 1 ng/mL and 1 ng/mL to 20 ng/mL, with the low detection limit (LOD) of 1.0 pg/mL.This immunosensor is simple, low-cost and sensitive and shows a great potential in biomedicine, clinical diagnosis and health examination.