在基于核磁共振(NMR)的代谢组学数据分析中,尺度缩放是关键的预处理步骤之一,其主要目的是通过调整数据的方差结构,改善后续的多变量统计分析的结果。从信息熵的角度出发,利用KullbackLeibler(K-L)散度来度量不同实验分组的生物样品的1 ...在基于核磁共振(NMR)的代谢组学数据分析中,尺度缩放是关键的预处理步骤之一,其主要目的是通过调整数据的方差结构,改善后续的多变量统计分析的结果。从信息熵的角度出发,利用KullbackLeibler(K-L)散度来度量不同实验分组的生物样品的1 H NMR波谱数据的差异程度,并结合单位方差缩放法,提出一种基于K-L散度的尺度缩放方法。该方法先利用单位方差法将数据各变量的标准差调整到同一水平上,再利用K-L散度对各变量进行有监督地加权,增强重要变量、减弱无关变量。由于K-L散度是在概率分布的意义上度量数据间的差异程度,且对于高斯和非高斯分布的数据均适用,因此能更准确地度量不同实验分组样品的1 H NMR波谱数据的差异性,从而更有效地地对谱数据的重要变量进行识别和加权。人群尿液1 H NMR波谱数据的分析结果表明,基于K-L散度的尺度缩放方法能有效抑制噪声变量,同时很好地区分特征变量和非特征变量;提高主成分回归(PCR)模型的判别能力;改善偏最小二乘回归判别分析(PLS-DA)模型的解释能力、预测能力以及对特征代谢物的辨识能力。展开更多
目的:基于核磁共振氢谱(1 H NMR)研究电针"内关"穴对心肌缺血再灌注损伤(MIRI)大鼠血清和心肌组织代谢物的影响,探讨电针"内关"穴对MIRI大鼠代谢模式的影响。方法:30只SD雄性大鼠随机分为对照组、模型组、电针组。...目的:基于核磁共振氢谱(1 H NMR)研究电针"内关"穴对心肌缺血再灌注损伤(MIRI)大鼠血清和心肌组织代谢物的影响,探讨电针"内关"穴对MIRI大鼠代谢模式的影响。方法:30只SD雄性大鼠随机分为对照组、模型组、电针组。对照组:不予电针,仅用鼠板束缚大鼠,每次20min,每日1次,持续7d;模型组予心肌缺血再灌注造模:至第7天后结扎冠状动脉左前降支40 min后恢复血流60 min;电针组(频率10Hz/50Hz,脉冲宽度0.5ms,强度1mA):每日电针双侧"内关"穴1次,时间20min,持续7d,于第7天电针后造模。造模结束后,收集3组大鼠的血清和心肌组织。利用1 H NMR进行代谢物检测并利用多元统计方法主成分分析(PCA)、正交偏最小二乘分析(OPLS-DA)进行模式识别。结果:与对照组相比,模型组大鼠血清的亮氨酸、异亮氨酸、缬氨酸、3-羟基丁酸、乳酸、丙氨酸、赖氨酸、醋酸盐、N-乙酰糖蛋白、丙酮、乙酰乙酸、琥珀酸、谷氨酰胺、多不饱和脂肪酸、肌酸、甘油磷酸胆碱、甘氨酸均浓度下降,低密度脂蛋白/极低密度脂蛋白、葡萄糖浓度上升;其中除丙酮、乙酰乙酸和多不饱和脂肪酸外,低密度脂蛋白/极低密度脂蛋白在电针后下降到接近对照组水平,其它代谢物浓度均在电针后上升到接近对照组水平,电针组大鼠血清的代谢模式更接近对照组。与对照组相比,模型组大鼠心肌组织的乳酸、丙氨酸、赖氨酸、谷氨酸、谷氨酰胺、天冬氨酸、甘油磷酸胆碱、肌酸、牛磺酸、甘氨酸、苏氨酸、腺苷一磷酸、烟酰胺腺嘌呤二核苷酸浓度下降,葡萄糖浓度明显上升;其中肌酸、甘油磷酸胆碱、烟酰胺腺嘌呤二核苷酸浓度在电针后上升,葡萄糖浓度在电针后下降;此外,电针组大鼠心肌组织苏氨酸、腺苷一磷酸浓度较模型组进一步下降;电针组大鼠心肌的代谢模式虽然有向对照组偏移的趋势,但与对照组差异还是较大。结论:电针"内关"穴可调节MIRI大鼠糖代谢、脂肪酸代谢、氨基酸代谢及能量代谢,对心肌具有一定的保护作用,但其具体的代谢通路及机制需要进一步研究。展开更多
The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the...The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.展开更多
The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultu...The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultural characteristics were used to identify the species, which known, and being described as Phaeoacremonium aleophillum. This is the first report on identifying Phaeoacremonium aleophillum from Platanus in Iraq, previously reports accommodate Cephalosporium acremonium from Platanus trees. This specie is able to produce toxic metabolites. Applications of P. aleophillum crude and cell-free filtrates induced severe chlorosis and necrosis on Platanus leaves after 24 hours of treatment with P. aleophillum culture filtrate. A novel phytotoxin was isolated from P. aleophillurn and culture filtrate was identified as galactouronic acid.展开更多
文摘在基于核磁共振(NMR)的代谢组学数据分析中,尺度缩放是关键的预处理步骤之一,其主要目的是通过调整数据的方差结构,改善后续的多变量统计分析的结果。从信息熵的角度出发,利用KullbackLeibler(K-L)散度来度量不同实验分组的生物样品的1 H NMR波谱数据的差异程度,并结合单位方差缩放法,提出一种基于K-L散度的尺度缩放方法。该方法先利用单位方差法将数据各变量的标准差调整到同一水平上,再利用K-L散度对各变量进行有监督地加权,增强重要变量、减弱无关变量。由于K-L散度是在概率分布的意义上度量数据间的差异程度,且对于高斯和非高斯分布的数据均适用,因此能更准确地度量不同实验分组样品的1 H NMR波谱数据的差异性,从而更有效地地对谱数据的重要变量进行识别和加权。人群尿液1 H NMR波谱数据的分析结果表明,基于K-L散度的尺度缩放方法能有效抑制噪声变量,同时很好地区分特征变量和非特征变量;提高主成分回归(PCR)模型的判别能力;改善偏最小二乘回归判别分析(PLS-DA)模型的解释能力、预测能力以及对特征代谢物的辨识能力。
文摘目的:基于核磁共振氢谱(1 H NMR)研究电针"内关"穴对心肌缺血再灌注损伤(MIRI)大鼠血清和心肌组织代谢物的影响,探讨电针"内关"穴对MIRI大鼠代谢模式的影响。方法:30只SD雄性大鼠随机分为对照组、模型组、电针组。对照组:不予电针,仅用鼠板束缚大鼠,每次20min,每日1次,持续7d;模型组予心肌缺血再灌注造模:至第7天后结扎冠状动脉左前降支40 min后恢复血流60 min;电针组(频率10Hz/50Hz,脉冲宽度0.5ms,强度1mA):每日电针双侧"内关"穴1次,时间20min,持续7d,于第7天电针后造模。造模结束后,收集3组大鼠的血清和心肌组织。利用1 H NMR进行代谢物检测并利用多元统计方法主成分分析(PCA)、正交偏最小二乘分析(OPLS-DA)进行模式识别。结果:与对照组相比,模型组大鼠血清的亮氨酸、异亮氨酸、缬氨酸、3-羟基丁酸、乳酸、丙氨酸、赖氨酸、醋酸盐、N-乙酰糖蛋白、丙酮、乙酰乙酸、琥珀酸、谷氨酰胺、多不饱和脂肪酸、肌酸、甘油磷酸胆碱、甘氨酸均浓度下降,低密度脂蛋白/极低密度脂蛋白、葡萄糖浓度上升;其中除丙酮、乙酰乙酸和多不饱和脂肪酸外,低密度脂蛋白/极低密度脂蛋白在电针后下降到接近对照组水平,其它代谢物浓度均在电针后上升到接近对照组水平,电针组大鼠血清的代谢模式更接近对照组。与对照组相比,模型组大鼠心肌组织的乳酸、丙氨酸、赖氨酸、谷氨酸、谷氨酰胺、天冬氨酸、甘油磷酸胆碱、肌酸、牛磺酸、甘氨酸、苏氨酸、腺苷一磷酸、烟酰胺腺嘌呤二核苷酸浓度下降,葡萄糖浓度明显上升;其中肌酸、甘油磷酸胆碱、烟酰胺腺嘌呤二核苷酸浓度在电针后上升,葡萄糖浓度在电针后下降;此外,电针组大鼠心肌组织苏氨酸、腺苷一磷酸浓度较模型组进一步下降;电针组大鼠心肌的代谢模式虽然有向对照组偏移的趋势,但与对照组差异还是较大。结论:电针"内关"穴可调节MIRI大鼠糖代谢、脂肪酸代谢、氨基酸代谢及能量代谢,对心肌具有一定的保护作用,但其具体的代谢通路及机制需要进一步研究。
基金Supported by the National Natural Science Foundation of China (No.41106102)Shandong Science Foundation of China (No. ZR2009CZ008)the 100 Talents Program of the Chinese Academy of Sciences
文摘The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.
文摘The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultural characteristics were used to identify the species, which known, and being described as Phaeoacremonium aleophillum. This is the first report on identifying Phaeoacremonium aleophillum from Platanus in Iraq, previously reports accommodate Cephalosporium acremonium from Platanus trees. This specie is able to produce toxic metabolites. Applications of P. aleophillum crude and cell-free filtrates induced severe chlorosis and necrosis on Platanus leaves after 24 hours of treatment with P. aleophillum culture filtrate. A novel phytotoxin was isolated from P. aleophillurn and culture filtrate was identified as galactouronic acid.
