Rhizoma paridis saponins protected against liver injury in diethylnitrosamine-induced mice

Background:Diethylnitrosamine,one of food additives,possessed a strong carcinogenic effect in human.Rhizoma paridis saponins,as the main active components of Paris polyphylla,have a good anti-cancer effect in our previous research.To verify their inhibitory effect on diethylnitrosamine-induced liver cancer,we carried out this study.Methods:We established diethylnitrosamine-induced mouse hepatocarcinoma models to evaluate antitumor of Rhizoma paridis saponins.Subsequently,gas chromatography-mass spectrometry was applied to analyze the metabolites in the urine and serum samples.Results:Rhizoma paridis saponins alleviated diethylnitrosamine-induced hepatocarcinogenesis.On the one hand,Rhizoma paridis saponins down-regulated the levels of liver function markers,such as alanine aminotransferase,aspartate transaminase and alpha fetoprotein.On the other hand,Rhizoma paridis saponins reduced metabolic disorders by increasing fructose and mannose metabolism,and decreasing pentose and glucuronate interconversion,inositol phosphate metabolism,and the process of saturated fatty acids transforming to unsaturated fatty acids,which based on the regulating mRNA expression of glucose transporter type 4,lactate dehydrogenase A,fatty acid synthetas,acetyl-CoA carboxylase and apolipoprotein A-I.Conclusion:Rhizoma paridis saponins has the potential application to inhibit chemical-induced hepatocarcinogenesis in the future.

Efficient soluble deep blue electroluminescent dianthracenylphenylene emitters with CIE y(y≤0.08) based on triplet-triplet annihilation

It has been challenging to develop deep blue organic molecular fluorescent emitters with CIE y(y≤0.08)based on triplet-triplet annihilation(TTA). Here, we report facilely available dianthracenylphenylenebased emitters, which have a 3,5-di(4-t-butylphenyl)phenyl moiety at the one end and 4-cyanophenyl or 3-pyridyl at the other end, respectively. Both fluorophores show a high glass transition temperature of over 220℃ with a thermal decomposition temperature of over 430℃ at an initial weight loss of1%. The preliminary characterizations of the organic light-emitting diodes(OLEDs) that utilized these nondoped emitters provided high EQEs of 4.6%à5.9% with CIE coordinates(0.15, 0.07–0.08). The analysis of the EL transient decay revealed that TTA contributed to the observed performance. The results show that the new emitters are attractive as a potential TTA-based host to afford stable deep blue fluorescent OLEDs.

Effect of multiple heat treatments on fracture property of centrifugal casting stainless steels Z3CN20.09M with long-term thermal aging degradation

It is of great significance to investigate effect of multiple heat treatments on fracture property of centrifugal casting stainless steels Z3CN20.09M cut from pump casing with long-term thermal aging degradation for nuclear power plants to consider actual operation of nuclear power plants.Both multiple heat treatments and accelerated thermal aging experiment at the same temperature of 400℃ for different time were successively carried out on centrifugal casting stainless steels Z3CN20.09M in order to examine the metallographic modification and impact properties.Finally,an additional investigation on the related fracture properties was carried out,in which the critical initial fracture toughness Ji was determined by stretch zone width and 0.2 mm offset line methods.These results indicated that the multiple heat treatments led to the dispersed distribution of ferrite phases in austenite matrix and thus microhardness increased,but impact energy exhibited a decreasing tendency significantly.After long-term aging,the metallographic structure remained almost unchanged,but the size of ferrite phases showed a slight increasing trend because of spinodal decomposition in ferrite phases and G-phase precipitation.In addition,centrifugal casting stainless steels Z3CN20.09M with multiple heat treatments exhibited the higher microhardness,Charpy impact toughness,critical initial fracture toughness J_(IC)(J-integral determined by 0.2 mm offset line method),and J_(SZW)(J-integral determined by stretch zone width method)than those with primary heat treatment,while the specific number of the heat treatment had a low influence on fracture toughness.