In traditional Chinese medicine herbs(TCM),including Radix Salviae Miltiorrhizae(Danshen),Radix Puerariae Lobatae(Gegen),Radix Angelicae Sinensis(Danggui),and Rhizoma Chuanxiong(Chuanxiong)are widely used for the prev...In traditional Chinese medicine herbs(TCM),including Radix Salviae Miltiorrhizae(Danshen),Radix Puerariae Lobatae(Gegen),Radix Angelicae Sinensis(Danggui),and Rhizoma Chuanxiong(Chuanxiong)are widely used for the prevention and treatment of cardiovascular diseases and also often co-administered with Western drugs as a part of integrative medicine practice.Carboxylesterase 1(CES1)plays a pivotal role in the metabolisms of pro-drugs,Since(S)-2-(2-(6-dimethylamino)-benzothiazole)-4,5-dihydrothiazole-4-carboxylate(NLMe)has recently been identified by us as a selective CES1 bioluminescent sensor,we developed a rapid method using this substrate for the direct measurement of CES1 activity in rats.This bioluminescence assay was applied to determine CES1 activity in rat tissues after a two-week oral administration of each of the four herbs noted above.The results demonstrated the presence of CES1 enzyme in rat blood and all tested tissues with much higher enzyme activity in the blood,liver,kidney and heart than that in the small intestine,spleen,lung,pancreas,brain and stomach.In addition,the four herbs showed tissue-specific effects on rat CES1 expression.Based on the CES1 biodistribution and its changes after treatment in rats,the possibility that Danshen,Gegen and Danggui might alter CES1 activities in human blood and kidney should be considered.In summary,a selective and sensitive bioluminescence assay was developed to rapidly evaluate CES1 activity and the effects of orally administered TCMs in rats.展开更多
Underground fires are slow spreading,long-lasting and low temperature smoldering combustion without flames,mainly occurring in peatlands and wetlands with rich organic matter.The spread of the smoldering is maintained...Underground fires are slow spreading,long-lasting and low temperature smoldering combustion without flames,mainly occurring in peatlands and wetlands with rich organic matter.The spread of the smoldering is maintained by heat released during combustion and monitoring this is an important approach to detect underground fires.The Daxing'an Mountains region is a hotspot for underground fires in northeast China.This study examined a L arix gmelinii plantation in the Tatou wetlands of the Daxing'an Mountains and determined the maximum temperature variation of humus of varying particle sizes,and the temperature rising process based on non-linear mixed effects models by an indoor combustion experiment.Maximum combustion temperatures up to 897.5°C,increased with humus depth;among the three models tested,Richard's equations were best for characterizing temperature variations;a non-linear equation with three parameters had the highest accuracy in fitting the combustion temperature variations with varying humus particle sizes.These results are informative for predicting temperature variations and provide technical support for underground fire monitoring.展开更多
基金supported by Health and Medical Research Fund(Reference No.:12131521)from Food and Health Bureau,the Government of the Hong Kong SAR,Hong Kong,ChinaNational Natural Science Foundation of China(Grant No.:81973286,81922070,81703604 and 81973393),ChinaGeneral Research Fund(CUHK2141142)from University Grant Council of Hong Kong SAR,China。
文摘In traditional Chinese medicine herbs(TCM),including Radix Salviae Miltiorrhizae(Danshen),Radix Puerariae Lobatae(Gegen),Radix Angelicae Sinensis(Danggui),and Rhizoma Chuanxiong(Chuanxiong)are widely used for the prevention and treatment of cardiovascular diseases and also often co-administered with Western drugs as a part of integrative medicine practice.Carboxylesterase 1(CES1)plays a pivotal role in the metabolisms of pro-drugs,Since(S)-2-(2-(6-dimethylamino)-benzothiazole)-4,5-dihydrothiazole-4-carboxylate(NLMe)has recently been identified by us as a selective CES1 bioluminescent sensor,we developed a rapid method using this substrate for the direct measurement of CES1 activity in rats.This bioluminescence assay was applied to determine CES1 activity in rat tissues after a two-week oral administration of each of the four herbs noted above.The results demonstrated the presence of CES1 enzyme in rat blood and all tested tissues with much higher enzyme activity in the blood,liver,kidney and heart than that in the small intestine,spleen,lung,pancreas,brain and stomach.In addition,the four herbs showed tissue-specific effects on rat CES1 expression.Based on the CES1 biodistribution and its changes after treatment in rats,the possibility that Danshen,Gegen and Danggui might alter CES1 activities in human blood and kidney should be considered.In summary,a selective and sensitive bioluminescence assay was developed to rapidly evaluate CES1 activity and the effects of orally administered TCMs in rats.
基金funded by the National Natural Science Foundation of China(Grant No.31971669)。
文摘Underground fires are slow spreading,long-lasting and low temperature smoldering combustion without flames,mainly occurring in peatlands and wetlands with rich organic matter.The spread of the smoldering is maintained by heat released during combustion and monitoring this is an important approach to detect underground fires.The Daxing'an Mountains region is a hotspot for underground fires in northeast China.This study examined a L arix gmelinii plantation in the Tatou wetlands of the Daxing'an Mountains and determined the maximum temperature variation of humus of varying particle sizes,and the temperature rising process based on non-linear mixed effects models by an indoor combustion experiment.Maximum combustion temperatures up to 897.5°C,increased with humus depth;among the three models tested,Richard's equations were best for characterizing temperature variations;a non-linear equation with three parameters had the highest accuracy in fitting the combustion temperature variations with varying humus particle sizes.These results are informative for predicting temperature variations and provide technical support for underground fire monitoring.