Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation....Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation.Here, we compared the osteogenic potential of MSCs from young and adult rats under three rounds of 2 h of cyclic stretch of 2.5% elongation at 1 Hz on 3 consecutive days. Cyclic stretch induced a significant osteogenic differentiation of MSCs from young rats, while a compromised osteogenesis in MSCs from the adult rats.Accordingly, there were much more reactive oxygen species(ROS) production in adult MSCs under cyclic stretch compared to young MSCs. Moreover, ROS scavenger N-acetylcysteine rescued the osteogenic differentiation of adult MSCs under cyclic stretch. Gene expression analysis revealed that superoxide dismutase 1(SOD1) was significantly downregulated in those MSCs from adult rats. In summary, our data suggest that reduced SOD1 may result in excessive ROS production in adult MSCs under cyclic stretch, and thus manipulation of the MSCs from the adult donors with antioxidant would improve their osteogenic ability.展开更多
The so-called zebra sole includes a group of small flatfishes characterized by transverse band pairs on the ocular side and distributed throughout shallow waters along the coast of the Indo-West Pacific Ocean. Sev-era...The so-called zebra sole includes a group of small flatfishes characterized by transverse band pairs on the ocular side and distributed throughout shallow waters along the coast of the Indo-West Pacific Ocean. Sev-eral species of the zebra sole have been recorded from the coastal waters of China. Morphological analysis of 1 107 specimens of the zebra sole from 15 successive localities along the China’s coast demonstrated that no significant variations among these localities were found on the basis of meristic counts and morphometric characters. Phylogenetic analysis based onCOI gene sequences of 14 individuals and D-loop of 22 indi-viduals from eight localities showed that they were indistinguishable among these localities. Therefore, both morphological and molecular evidence supported the occurrence of a single species of the zebra sole along the China’s coast. The available name for this species isZebriaszebrinus (Temminck and Schlegel, 1846) in-stead ofZ.zebra (Bloch, 1787).Zebrias fasciatus(Basilewsky, 1855) andSolea ommatura (Richardson, 1846) are considered here as two synonyms ofZ. zebrinus.展开更多
Alzheimer’s disease is a progressive neurodegenerative disorder, characterized by deposition of amyloid beta, neurofibrillary tangles, astrogliosis and microgliosis, leading to neuronal dysfunction and loss in the br...Alzheimer’s disease is a progressive neurodegenerative disorder, characterized by deposition of amyloid beta, neurofibrillary tangles, astrogliosis and microgliosis, leading to neuronal dysfunction and loss in the brain. Current treatments for Alzheimer’s disease primarily focus on enhancement of cholinergic transmission. However, these treatments are only symptomatic, and no disease-modifying drug is available for Alzheimer’s disease patients. This review will provide an overview of the proven antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognition-enhancing effects of curcumin and apigenin and discuss the potential of these compounds for Alzheimer’s disease prevention and treatment. We suggest that these compounds might delay the onset of Alzheimer’s disease or slow down its progression, and they should enter clinical trials as soon as possible.展开更多
In this study,acetone extracts of thirteen different species distributed in Turkey Coasts including tunicates,sea anemones,sponges and corals were investigated for their superoxide(SO)radical scavenging and cytotoxic ...In this study,acetone extracts of thirteen different species distributed in Turkey Coasts including tunicates,sea anemones,sponges and corals were investigated for their superoxide(SO)radical scavenging and cytotoxic activities.VWhile SO radical scavenging activity was tested using alkaline DMSO method,cytotoxic activity was tested by MTT assay against Hep-2 cancer cell line.As a result of bioactivity studies,Paramuricea clavata extract showed展开更多
Nickel-iron sulfide has shown attractive activity in electrocatalytic oxygen evolution reaction(OER).However,the effects of low valence sulfur(S^(2−))and metal species on OER in binary nickel-iron sulfide have rarely ...Nickel-iron sulfide has shown attractive activity in electrocatalytic oxygen evolution reaction(OER).However,the effects of low valence sulfur(S^(2−))and metal species on OER in binary nickel-iron sulfide have rarely been systematically studied.Works based on post-catalysis characterization have led to the assumption that the real active species are nickel-iron oxyhydroxide,and that nickel-iron sulfide acts only as a precatalyst.Therefore,to study the role of S,Ni,and Fe for the development of nickel-iron sulfide catalyst is of self-evident importance.Herein,a facile solvothermal method is used to synthesize acetylene black coated with nickel-iron sulfide nanosheets.Electrochemical tests show that the presence of low valence S species makes the catalyst have faster OER kinetics,larger active area,and intermediate active species adsorption area.Therefore,the present study reveals the enhancing effect of low valence sulfur species(S^(2−))on OER in binary nickel-iron sulfide.In situ Raman spectroscopy shows that the generation ofγ-NiOOH intermediate is essential and Fe does not directly participate in the oxygen production.Density functional theory(DFT)calculation shows that Ni-OH deprotonation is a rate-determining step for both binary nickel-iron sulfide and nickel sulfide.The addition of Fe into NiSx lightly increases the charge transfer of Ni atom to O atom,which makes deprotonation easier and thereby improves the OER performance.展开更多
基金financially supported by National Natural Science Foundation of China (81100240)‘985’ project of Sun Yat-Sen University grant+2 种基金Sun Yat-Sen university young teachers training project (13YKPY42)Natural Science Foundation of Guangdong Province,China(S2012010009495)Science and Technology Planning Project of Guangdong Province,China(2012B031800185)
文摘Age related defect of the osteogenic differentiation of mesenchymal stem cells(MSCs) plays a key role in osteoporosis. Mechanical loading is one of the most important physical stimuli for osteoblast differentiation.Here, we compared the osteogenic potential of MSCs from young and adult rats under three rounds of 2 h of cyclic stretch of 2.5% elongation at 1 Hz on 3 consecutive days. Cyclic stretch induced a significant osteogenic differentiation of MSCs from young rats, while a compromised osteogenesis in MSCs from the adult rats.Accordingly, there were much more reactive oxygen species(ROS) production in adult MSCs under cyclic stretch compared to young MSCs. Moreover, ROS scavenger N-acetylcysteine rescued the osteogenic differentiation of adult MSCs under cyclic stretch. Gene expression analysis revealed that superoxide dismutase 1(SOD1) was significantly downregulated in those MSCs from adult rats. In summary, our data suggest that reduced SOD1 may result in excessive ROS production in adult MSCs under cyclic stretch, and thus manipulation of the MSCs from the adult donors with antioxidant would improve their osteogenic ability.
基金The Key Innovation Project of Chinese Academy of Sciences under contract No.KSCX2-YW-Z-0929the National Natural Science Foundation of China under contract Nos 30870283 and 31071890
文摘The so-called zebra sole includes a group of small flatfishes characterized by transverse band pairs on the ocular side and distributed throughout shallow waters along the coast of the Indo-West Pacific Ocean. Sev-eral species of the zebra sole have been recorded from the coastal waters of China. Morphological analysis of 1 107 specimens of the zebra sole from 15 successive localities along the China’s coast demonstrated that no significant variations among these localities were found on the basis of meristic counts and morphometric characters. Phylogenetic analysis based onCOI gene sequences of 14 individuals and D-loop of 22 indi-viduals from eight localities showed that they were indistinguishable among these localities. Therefore, both morphological and molecular evidence supported the occurrence of a single species of the zebra sole along the China’s coast. The available name for this species isZebriaszebrinus (Temminck and Schlegel, 1846) in-stead ofZ.zebra (Bloch, 1787).Zebrias fasciatus(Basilewsky, 1855) andSolea ommatura (Richardson, 1846) are considered here as two synonyms ofZ. zebrinus.
文摘Alzheimer’s disease is a progressive neurodegenerative disorder, characterized by deposition of amyloid beta, neurofibrillary tangles, astrogliosis and microgliosis, leading to neuronal dysfunction and loss in the brain. Current treatments for Alzheimer’s disease primarily focus on enhancement of cholinergic transmission. However, these treatments are only symptomatic, and no disease-modifying drug is available for Alzheimer’s disease patients. This review will provide an overview of the proven antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognition-enhancing effects of curcumin and apigenin and discuss the potential of these compounds for Alzheimer’s disease prevention and treatment. We suggest that these compounds might delay the onset of Alzheimer’s disease or slow down its progression, and they should enter clinical trials as soon as possible.
基金supported by the Turkish Academy of Science,Young Scientist Award(TUBA-GEBIP/2013)
文摘In this study,acetone extracts of thirteen different species distributed in Turkey Coasts including tunicates,sea anemones,sponges and corals were investigated for their superoxide(SO)radical scavenging and cytotoxic activities.VWhile SO radical scavenging activity was tested using alkaline DMSO method,cytotoxic activity was tested by MTT assay against Hep-2 cancer cell line.As a result of bioactivity studies,Paramuricea clavata extract showed
基金the National Natural Science Foundation of China(No.21901007)the Natural Science Foundation of Anhui Province(No.2008085QB83).
文摘Nickel-iron sulfide has shown attractive activity in electrocatalytic oxygen evolution reaction(OER).However,the effects of low valence sulfur(S^(2−))and metal species on OER in binary nickel-iron sulfide have rarely been systematically studied.Works based on post-catalysis characterization have led to the assumption that the real active species are nickel-iron oxyhydroxide,and that nickel-iron sulfide acts only as a precatalyst.Therefore,to study the role of S,Ni,and Fe for the development of nickel-iron sulfide catalyst is of self-evident importance.Herein,a facile solvothermal method is used to synthesize acetylene black coated with nickel-iron sulfide nanosheets.Electrochemical tests show that the presence of low valence S species makes the catalyst have faster OER kinetics,larger active area,and intermediate active species adsorption area.Therefore,the present study reveals the enhancing effect of low valence sulfur species(S^(2−))on OER in binary nickel-iron sulfide.In situ Raman spectroscopy shows that the generation ofγ-NiOOH intermediate is essential and Fe does not directly participate in the oxygen production.Density functional theory(DFT)calculation shows that Ni-OH deprotonation is a rate-determining step for both binary nickel-iron sulfide and nickel sulfide.The addition of Fe into NiSx lightly increases the charge transfer of Ni atom to O atom,which makes deprotonation easier and thereby improves the OER performance.