A 72-year-old male underwent neck dissection and parotidectomy with facial nerve preservation. Endotracheal intubation was facilitated with succinylcholine. Prolonged muscle paralysis which was first detected after fa...A 72-year-old male underwent neck dissection and parotidectomy with facial nerve preservation. Endotracheal intubation was facilitated with succinylcholine. Prolonged muscle paralysis which was first detected after failure to stimulate the facial nerve with electrocautery, lasted five hours. Laboratory tests indicated pseudocholinesterase (PChE) deficiency. A thyroidectomy one month later was performed uneventfully using rocuronium as a muscle relaxant. Literature review revealed a total of 40 PChE deficiency cases being reported since 1956.展开更多
Due to their significant value in both economy and ecology,Daphnia had long been employed to investigate in vivo response of cholinesterase(ChE) in anticholinesterase exposures,whereas the type constitution and proper...Due to their significant value in both economy and ecology,Daphnia had long been employed to investigate in vivo response of cholinesterase(ChE) in anticholinesterase exposures,whereas the type constitution and property of the enzyme remained unclear.A type of ChE was purified from Daphnia magna using a three-step procedure,i.e.,Triton X-100 extraction,ammonium sulfate precipitation,and diethylaminoethyl(DEAE)-Sepharose Fast-Flow chromatography.According to sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE),molecular mass of the purified ChE was estimated to be 84 kDa.Based on substrate studies,the purified enzyme preferred butyrylthiocholine iodide(BTCh) [with maximum velocity(Vmax)/Michaelis constant(Km)=8.428 L/(min·mg protein)] to acetylthiocholine iodide(ATCh) [with V max /Km =5.346 L/(min·mg protein)] as its substrate.Activity of the purified enzyme was suppressed by high concentrations of either ATCh or BTCh.Inhibitor studies showed that the purified enzyme was more sensitive towards inhibition by tetraisopropylpyrophosphoramide(iso-OMPA) than by 1,5-bis(4-allyldimethylammoniumphenyl) pentan-3-one dibromide(BW284C51).Result of the study suggested that the purified ChE was more like a type of pseudocholinesterase,and it also suggested that Daphnia magna contained multiple types of ChE in their bodies.展开更多
文摘A 72-year-old male underwent neck dissection and parotidectomy with facial nerve preservation. Endotracheal intubation was facilitated with succinylcholine. Prolonged muscle paralysis which was first detected after failure to stimulate the facial nerve with electrocautery, lasted five hours. Laboratory tests indicated pseudocholinesterase (PChE) deficiency. A thyroidectomy one month later was performed uneventfully using rocuronium as a muscle relaxant. Literature review revealed a total of 40 PChE deficiency cases being reported since 1956.
基金Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY12B07008)the Department of Education of Zhejiang Province,China(No.20070138)
文摘Due to their significant value in both economy and ecology,Daphnia had long been employed to investigate in vivo response of cholinesterase(ChE) in anticholinesterase exposures,whereas the type constitution and property of the enzyme remained unclear.A type of ChE was purified from Daphnia magna using a three-step procedure,i.e.,Triton X-100 extraction,ammonium sulfate precipitation,and diethylaminoethyl(DEAE)-Sepharose Fast-Flow chromatography.According to sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE),molecular mass of the purified ChE was estimated to be 84 kDa.Based on substrate studies,the purified enzyme preferred butyrylthiocholine iodide(BTCh) [with maximum velocity(Vmax)/Michaelis constant(Km)=8.428 L/(min·mg protein)] to acetylthiocholine iodide(ATCh) [with V max /Km =5.346 L/(min·mg protein)] as its substrate.Activity of the purified enzyme was suppressed by high concentrations of either ATCh or BTCh.Inhibitor studies showed that the purified enzyme was more sensitive towards inhibition by tetraisopropylpyrophosphoramide(iso-OMPA) than by 1,5-bis(4-allyldimethylammoniumphenyl) pentan-3-one dibromide(BW284C51).Result of the study suggested that the purified ChE was more like a type of pseudocholinesterase,and it also suggested that Daphnia magna contained multiple types of ChE in their bodies.
