17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Ther...17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Therefore methods need to be developed to detect residues of 17α-methyltestosterone in aqueous matrices. A simple high-performance liquid chromatographic method using ultraviolet detection (245 nm) and testosterone as internal standard has been developed for the monitoring 17α-methyltestosterone in freshwater samples of tilapia aquaculture. The method described involves limited sample preparation as it includes a filtration followed by a single solid-phase extraction step using C18 cartridge. Validation data indicated that the HPLC-UV method for 17α-methyltestosterone determination in the concentration range of 50 - 2000 μg/L provided good linearity, sensitivity, accuracy and precision. Method performance was efficiently applied to monitoring the freshwater samples of fish ponds and the surrounding aquatic channels.展开更多
The effects of recombinant eel growth hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth of red sea bream. Pagrosomus major.were investigated.Administration of reGH to fry by immersion at 2 mg 1 f...The effects of recombinant eel growth hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth of red sea bream. Pagrosomus major.were investigated.Administration of reGH to fry by immersion at 2 mg 1 for 2 hevery 5 dsys resulted in significant increase in both weight and length.but the condition factor (CF) diminished relative to that of similarly treated controls over the 37day treatment period.Immersion in 0.1 mg:1 T4 also resulted in significant increase in both weight and length and higher survival rate of test fry compared to the controls. Immersion in MT had less effect on growth and high-dose resulted in high mortality.In the second study.injection of 2 μg reGH(gwk)caused a significant increase in the specific growth rate (SGR) of test red sea bream fingerlings relative to that of the controls during the 4-week treatment period and maintained the increasing trend over the post-treatment period (weeks 4-6).Injection of MT at a dosage of 1μg (gwk) resulted in a significant展开更多
目的观察黄芪建中汤对脾胃虚寒证胃溃疡大鼠炎症因子及HGF/c-Met信号通路的影响。方法将60只大鼠随机分为4组,即正常组、模型组、黄芪建中汤组[黄芪建中汤6.8 g/(kg·d)]、奥美拉唑组[奥美拉唑肠溶胶囊4.2 mg/(kg·d)],每组15...目的观察黄芪建中汤对脾胃虚寒证胃溃疡大鼠炎症因子及HGF/c-Met信号通路的影响。方法将60只大鼠随机分为4组,即正常组、模型组、黄芪建中汤组[黄芪建中汤6.8 g/(kg·d)]、奥美拉唑组[奥美拉唑肠溶胶囊4.2 mg/(kg·d)],每组15只大鼠。正常组除外,其他组采用耗气破气法结合饥饱失常法进行大鼠脾胃虚寒证模型造模,再采用冰醋酸法建立大鼠胃溃疡模型。比较各组大鼠体质量、溃疡指数;HE染色观察大鼠胃组织病理学变化;采用酶联免疫吸附法检测血清中白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)含量;免疫组化法检测胃组织中肝细胞生长因子(HGF)、肝细胞生长因子受体(c-Met)表达;荧光定量PCR检测胃组织HGF、c-Met m RNA水平。结果与正常组相比,模型组大鼠体质量降低,溃疡指数升高,IL-6、IL-1β、TNF-α含量升高,HGF升高,HGF、c-Met m RNA升高(P<0.05);与模型组相比,黄芪建中汤组和奥美拉唑组大鼠体质量升高,溃疡指数降低,IL-6、IL-1β、TNF-α降低,HGF升高,HGF、c-Met mRNA升高(P<0.05)。结论黄芪建中汤可以通过抑制炎症因子、调节HGF/c-Met通路的表达促进胃黏膜修复。展开更多
Gastric cancer is among the most frequently occurring cancers and a leading cause of cancer-related deaths globally.Because gastric cancer is highly heterogenous and comprised of different subtypes with distinct molec...Gastric cancer is among the most frequently occurring cancers and a leading cause of cancer-related deaths globally.Because gastric cancer is highly heterogenous and comprised of different subtypes with distinct molecular and clinical characteristics,the management of gastric cancer calls for better-defined,biomarker-guided,molecular-based treatment strategies.MET is a receptor tyrosine kinase mediating important physiologic processes,such as embryogenesis,tissue regeneration,and wound healing.However,mounting evidence suggests that aberrant MET pathway activation contributes to tumour proliferation and metastasis in multiple cancer types,including gastric cancer,and is associated with poor patient outcomes.As such,MET-targeting therapies are being actively developed and promising progress has been demonstrated,especially with MET tyrosine kinase inhibitors.This review aims to briefly introduce the role of MET alterations in gastric cancer and summarize in detail the current progress of MET tyrosine kinase inhibitors in this disease area with a focus on savolitinib,tepotinib,capmatinib,and crizotinib.Building on current knowledge,this review further discusses existing challenges in MET alterations testing,possible resistance mechanisms to MET inhibitors,and future directions of MET-targeting therapies.展开更多
文摘17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Therefore methods need to be developed to detect residues of 17α-methyltestosterone in aqueous matrices. A simple high-performance liquid chromatographic method using ultraviolet detection (245 nm) and testosterone as internal standard has been developed for the monitoring 17α-methyltestosterone in freshwater samples of tilapia aquaculture. The method described involves limited sample preparation as it includes a filtration followed by a single solid-phase extraction step using C18 cartridge. Validation data indicated that the HPLC-UV method for 17α-methyltestosterone determination in the concentration range of 50 - 2000 μg/L provided good linearity, sensitivity, accuracy and precision. Method performance was efficiently applied to monitoring the freshwater samples of fish ponds and the surrounding aquatic channels.
文摘The effects of recombinant eel growth hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth of red sea bream. Pagrosomus major.were investigated.Administration of reGH to fry by immersion at 2 mg 1 for 2 hevery 5 dsys resulted in significant increase in both weight and length.but the condition factor (CF) diminished relative to that of similarly treated controls over the 37day treatment period.Immersion in 0.1 mg:1 T4 also resulted in significant increase in both weight and length and higher survival rate of test fry compared to the controls. Immersion in MT had less effect on growth and high-dose resulted in high mortality.In the second study.injection of 2 μg reGH(gwk)caused a significant increase in the specific growth rate (SGR) of test red sea bream fingerlings relative to that of the controls during the 4-week treatment period and maintained the increasing trend over the post-treatment period (weeks 4-6).Injection of MT at a dosage of 1μg (gwk) resulted in a significant
文摘目的研究幽门螺杆菌(Hp)对肝癌HepG2细胞原癌基因C-Met表达的影响。方法将Hp与HepG2细胞共同培养,设置空白对照组、Hp组、C-Met抑制剂空白组和C-Met抑制剂Hp组,每组设副孔5个,采用CCK8试剂盒检测HepG2细胞增殖活性,采用Western blot和qPCR方法检测C-Met原癌基因蛋白和mRNA表达水平。结果相较于空白对照组,Hp处理组HepG2细胞增殖活性升高且与时间呈正相关,而C-Met抑制剂可以抑制HepG2细胞的增殖活性。同时,Hp组HepG2细胞C-Met基因蛋白和mRNA表达水平均上调,C-Met抑制剂组则显著下调。相较于Hp共培养12 h,共培养24 h C-Met蛋白和mRNA表达水平均上调。结论Hp促进HepG2细胞的增殖可能与其提高原癌基因C-Met的蛋白及其mRNA表达水平有关,为后续更深入研究肝癌发生发展的复杂机制提供了理论依据。
文摘目的观察黄芪建中汤对脾胃虚寒证胃溃疡大鼠炎症因子及HGF/c-Met信号通路的影响。方法将60只大鼠随机分为4组,即正常组、模型组、黄芪建中汤组[黄芪建中汤6.8 g/(kg·d)]、奥美拉唑组[奥美拉唑肠溶胶囊4.2 mg/(kg·d)],每组15只大鼠。正常组除外,其他组采用耗气破气法结合饥饱失常法进行大鼠脾胃虚寒证模型造模,再采用冰醋酸法建立大鼠胃溃疡模型。比较各组大鼠体质量、溃疡指数;HE染色观察大鼠胃组织病理学变化;采用酶联免疫吸附法检测血清中白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)含量;免疫组化法检测胃组织中肝细胞生长因子(HGF)、肝细胞生长因子受体(c-Met)表达;荧光定量PCR检测胃组织HGF、c-Met m RNA水平。结果与正常组相比,模型组大鼠体质量降低,溃疡指数升高,IL-6、IL-1β、TNF-α含量升高,HGF升高,HGF、c-Met m RNA升高(P<0.05);与模型组相比,黄芪建中汤组和奥美拉唑组大鼠体质量升高,溃疡指数降低,IL-6、IL-1β、TNF-α降低,HGF升高,HGF、c-Met mRNA升高(P<0.05)。结论黄芪建中汤可以通过抑制炎症因子、调节HGF/c-Met通路的表达促进胃黏膜修复。
基金supported by the National Natural Science Foundation of China(Grant No.81602057)the Beijing Natural Science Foundation(Grant No.Z210015)。
文摘Gastric cancer is among the most frequently occurring cancers and a leading cause of cancer-related deaths globally.Because gastric cancer is highly heterogenous and comprised of different subtypes with distinct molecular and clinical characteristics,the management of gastric cancer calls for better-defined,biomarker-guided,molecular-based treatment strategies.MET is a receptor tyrosine kinase mediating important physiologic processes,such as embryogenesis,tissue regeneration,and wound healing.However,mounting evidence suggests that aberrant MET pathway activation contributes to tumour proliferation and metastasis in multiple cancer types,including gastric cancer,and is associated with poor patient outcomes.As such,MET-targeting therapies are being actively developed and promising progress has been demonstrated,especially with MET tyrosine kinase inhibitors.This review aims to briefly introduce the role of MET alterations in gastric cancer and summarize in detail the current progress of MET tyrosine kinase inhibitors in this disease area with a focus on savolitinib,tepotinib,capmatinib,and crizotinib.Building on current knowledge,this review further discusses existing challenges in MET alterations testing,possible resistance mechanisms to MET inhibitors,and future directions of MET-targeting therapies.