Hydrogen peroxide(H_2O_2) and free radicals cause oxidative stress, which induces cellular injuries, metabolic dysfunction, and even cell death in various clinical abnormalities. Fullerene(C_(60)) is critical fo...Hydrogen peroxide(H_2O_2) and free radicals cause oxidative stress, which induces cellular injuries, metabolic dysfunction, and even cell death in various clinical abnormalities. Fullerene(C_(60)) is critical for scavenging oxygen free radicals originated from cell metabolism, and reduced glutathione(GSH) is another important endogenous antioxidant. In this study, a novel water-soluble reduced glutathione fullerene derivative(C_(60)-GSH) was successfully synthesized, and its beneficial roles in protecting against H_2O_2-induced oxidative stress and apoptosis in cultured HEK 293 T cells were investigated. Fourier Transform infrared spectroscopy and 1H nuclear magnetic resonance were used to confirm the chemical structure of C_(60)-GSH. Our results demonstrated that C_(60)-GSH prevented the reactive oxygen species(ROS)-mediated cell damage. Additionally, C_(60)-GSH pretreatment significantly attenuated H_2O_2-induced superoxide dismutase(SOD) consumption and malondialdehyde(MDA) elevation. Furthermore, C_(60)-GSH inhibited intracellular calcium mobilization, and subsequent cell apoptosis via bcl-2/bax-caspase-3 signaling pathway induced by H_2O_2 stimulation in HEK 293 T cells. Importantly, these protective effects of C_(60)-GSH were superior to those of GSH. In conclusion, these results suggested that C_(60)-GSH has potential to protect against H_2O_2-induced cell apoptosis by scavenging free radicals and maintaining intracellular calcium homeostasis without evident toxicity.展开更多
Nowadays,several studies demonstrate that viewing nature has positive effects on human health and well-being.This essay discusses about the essential methods of viewing natural environment and their impacts on human w...Nowadays,several studies demonstrate that viewing nature has positive effects on human health and well-being.This essay discusses about the essential methods of viewing natural environment and their impacts on human well-being by clarifying four important theoretical models:reducing stress,lowering heart rate,improving outcome of surgery,and increasing attention.In addition,some important research results in this field are taken as examples to introduce research methods.By collecting and organizing existing studies and theories about the relationship between viewing nature and human well-being,the methods of viewing nature can be divided into two parts:viewing nature through specific media(e.g.,through a window,a book,a painting or a videotape)and being with the presence of nature.This study aims to clarify the research significance of viewing nature and find deficiency in this field to maximize the role of landscapes in human health and well-being.展开更多
新闻!新闻!美国的一家杂志the Journal of Occupational Health Psychology(职业健康心理杂志)载文认为把家里的宠物带到工作场所,能够reduce stress and improve their health!另外的好处还有:…foster(培养)social interaction(互相作...新闻!新闻!美国的一家杂志the Journal of Occupational Health Psychology(职业健康心理杂志)载文认为把家里的宠物带到工作场所,能够reduce stress and improve their health!另外的好处还有:…foster(培养)social interaction(互相作用)and are good for business.不过本文在谈到如此做法的drawbacks(缺点),倒也客观公允。展开更多
A set of universal equations on the reduced stress relaxation modulus with K-W-W stretched exponential function has been derived from the dynamics of α and β structural relaxation processes. In the present work, the...A set of universal equations on the reduced stress relaxation modulus with K-W-W stretched exponential function has been derived from the dynamics of α and β structural relaxation processes. In the present work, the K-W-W decay function is used to define the three types of relaxations (single α, single β relaxation and α-β co-relaxation), then their average times of relaxation are theoretically calculated from the reduced shear stress relaxation modulus and the relaxation time spectrum function H(τ). When the average time of co-relaxation, the reference temperatures (ficitive Tf and glass transition Tg) and the isostructural parameter achieved from the conditions of isostructural glass state are introduced into the reduced shear stress relaxation modulus (GT) under the equilibrium state, a set of correlations between isochoric fragility index (mvα, mvβ and mvαβ) and the coupling strength (α and β) under the reference temperatures are derived from the exact definition of isochoric fragility. So the theory of dynamic fragility for glass substances at isochoric state is developed. The theory can predict the following main features of structural relaxations and behavior of isochoric fragility: the temperature dependence of peak relaxation frequency exhibits a bifurcation with a pair of single α and single β relaxations; the temperature dependence of Stickel equation on 1/T exhibits two crossovers with VFTH(1) and VFTH(2) at the temperatures of Tf and Tg regime; there are two linear correlations between isochoric fragility index (mvα and mvβ) and the coupling strength. Fine agreements between the theoretical calculation and experimental results are obtained.展开更多
基金supported by the Nature Science Foundation Committee Projects of China(No.30470425)
文摘Hydrogen peroxide(H_2O_2) and free radicals cause oxidative stress, which induces cellular injuries, metabolic dysfunction, and even cell death in various clinical abnormalities. Fullerene(C_(60)) is critical for scavenging oxygen free radicals originated from cell metabolism, and reduced glutathione(GSH) is another important endogenous antioxidant. In this study, a novel water-soluble reduced glutathione fullerene derivative(C_(60)-GSH) was successfully synthesized, and its beneficial roles in protecting against H_2O_2-induced oxidative stress and apoptosis in cultured HEK 293 T cells were investigated. Fourier Transform infrared spectroscopy and 1H nuclear magnetic resonance were used to confirm the chemical structure of C_(60)-GSH. Our results demonstrated that C_(60)-GSH prevented the reactive oxygen species(ROS)-mediated cell damage. Additionally, C_(60)-GSH pretreatment significantly attenuated H_2O_2-induced superoxide dismutase(SOD) consumption and malondialdehyde(MDA) elevation. Furthermore, C_(60)-GSH inhibited intracellular calcium mobilization, and subsequent cell apoptosis via bcl-2/bax-caspase-3 signaling pathway induced by H_2O_2 stimulation in HEK 293 T cells. Importantly, these protective effects of C_(60)-GSH were superior to those of GSH. In conclusion, these results suggested that C_(60)-GSH has potential to protect against H_2O_2-induced cell apoptosis by scavenging free radicals and maintaining intracellular calcium homeostasis without evident toxicity.
文摘Nowadays,several studies demonstrate that viewing nature has positive effects on human health and well-being.This essay discusses about the essential methods of viewing natural environment and their impacts on human well-being by clarifying four important theoretical models:reducing stress,lowering heart rate,improving outcome of surgery,and increasing attention.In addition,some important research results in this field are taken as examples to introduce research methods.By collecting and organizing existing studies and theories about the relationship between viewing nature and human well-being,the methods of viewing nature can be divided into two parts:viewing nature through specific media(e.g.,through a window,a book,a painting or a videotape)and being with the presence of nature.This study aims to clarify the research significance of viewing nature and find deficiency in this field to maximize the role of landscapes in human health and well-being.
文摘新闻!新闻!美国的一家杂志the Journal of Occupational Health Psychology(职业健康心理杂志)载文认为把家里的宠物带到工作场所,能够reduce stress and improve their health!另外的好处还有:…foster(培养)social interaction(互相作用)and are good for business.不过本文在谈到如此做法的drawbacks(缺点),倒也客观公允。
基金supported by the National Natural Science Foundation of China (Grant No. 50973007)
文摘A set of universal equations on the reduced stress relaxation modulus with K-W-W stretched exponential function has been derived from the dynamics of α and β structural relaxation processes. In the present work, the K-W-W decay function is used to define the three types of relaxations (single α, single β relaxation and α-β co-relaxation), then their average times of relaxation are theoretically calculated from the reduced shear stress relaxation modulus and the relaxation time spectrum function H(τ). When the average time of co-relaxation, the reference temperatures (ficitive Tf and glass transition Tg) and the isostructural parameter achieved from the conditions of isostructural glass state are introduced into the reduced shear stress relaxation modulus (GT) under the equilibrium state, a set of correlations between isochoric fragility index (mvα, mvβ and mvαβ) and the coupling strength (α and β) under the reference temperatures are derived from the exact definition of isochoric fragility. So the theory of dynamic fragility for glass substances at isochoric state is developed. The theory can predict the following main features of structural relaxations and behavior of isochoric fragility: the temperature dependence of peak relaxation frequency exhibits a bifurcation with a pair of single α and single β relaxations; the temperature dependence of Stickel equation on 1/T exhibits two crossovers with VFTH(1) and VFTH(2) at the temperatures of Tf and Tg regime; there are two linear correlations between isochoric fragility index (mvα and mvβ) and the coupling strength. Fine agreements between the theoretical calculation and experimental results are obtained.