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Plasma-assisted synthesis of porous bismuth nanosheets for electrocatalytic CO_(2)-to-formate reduction
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作者 Liangping Xiao Qizheng Zheng +5 位作者 Rusen Zhou Sifan Liu Yifan Zhao Yadong Zhao Renwu Zhou Kostya Ken Ostrikov 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期19-28,共10页
The electrochemical carbon dioxide reduction(eCO_(2)RR)to formate,driven by clean energy,is a promising approach for producing renewable chemicals and high-value fuels.Despite its potential,further development faces c... The electrochemical carbon dioxide reduction(eCO_(2)RR)to formate,driven by clean energy,is a promising approach for producing renewable chemicals and high-value fuels.Despite its potential,further development faces challenges due to limitations in electrocatalytic activity and durability,especially for nonnoble metal-based catalysts.Here,naturally abundant bismuth-based nanosheets that can effectively drive CO_(2)-to-formate electrocatalytic reduction are prepared using the plasma-activated Bi_(2)Se_(3) followed by a reduction process.Thus-obtained plasma-activated Bi nanosheets(P-BiNS)feature ultrathin structures and high surface areas.Such nanostructures ensure the P-BiNS with outstanding eCO_(2)RR catalytic performance,highlighted by the current density of over 80 mA cm^(-2) and a formate Faradic efficiency of>90%.Furthermore,P-BiNS catalysts demonstrate excellent durability and stability without deactivation following over 50h of operation.The selectivity for formate production is also studied by density functional theory(DFT)calculations,validating the importance and efficacy of the stabilization of intermediates(^(*)OCHO)on the P-BiNS surfaces.This study provides a facile plasma-assisted approach for developing high-performance and low-cost electrocatalysts. 展开更多
关键词 Plasma-assisted synthesis Plasmaa ctivation Bismuth nanosheet CO_(2)RR FORMATE
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Research on the Bending Impact Resistance and Transverse Fracture Characteristics of Bamboo under the Action of Falling Weight
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作者 Hao Jia Benhua Fei +4 位作者 Changhua Fang Huanrong Liu Xiubiao Zhang Xinxin Ma Fengbo Sun 《Journal of Renewable Materials》 SCIE EI 2023年第1期473-490,共18页
Drop weight impact tester was used to accurately measure the bending impact resistance of various parts of Phyllostachys edulis,commonly known as moso bamboo,with a growth cycle of 3–8 years.Cellulose crystallinity i... Drop weight impact tester was used to accurately measure the bending impact resistance of various parts of Phyllostachys edulis,commonly known as moso bamboo,with a growth cycle of 3–8 years.Cellulose crystallinity in the bottom(B),middle(M)and top(T)of bamboo at different ages was calculated using peak height analysis in X-ray diffraction.Heatmap of Spearman correlation analysis was used to represent the correlation between chemical composition and impact mechanics.The breaking load(BL),fracture energy(FE)and impact deflection(ID)of 3–8-year-old bamboo were found to be in the range of~670–2120 N,~5.17–15.55 J,and~3.60–~17.76 mm,respectively.As the growth period of bamboo rises,the cellulose crystallinity at the B and T decreases first and then increases,while that for the M increases first and then remains stable.Similarly,the bending impact performance of bamboo was found to become stable with its growth and age.The flexural impact and toughness of the 4-year-old bamboo base material were better than other specimens.The enhancement in the bending impact properties of bamboo at different growth periods was influenced by the lignin content,while the value of FE was mainly positively correlated with ash,cold and hot water extracts and benzyl alcohol content.However the content of holocellulose and pentosan,air-dry density and,base density negatively influenced the FE.With the change in the height of the bamboo,the correlation between its impact mechanical properties and chemical composition gradually decreased.This study provides data support and theoretical basis for the age-appropriate thinning and application of moso bamboo. 展开更多
关键词 Moso bamboo LIFESPAN bending impact breaking load fracture energy impact deflection chemical composition correlation
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Nanozyme‑Engineered Hydrogels for Anti‑Inflammation and Skin Regeneration
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作者 Amal George Kurian Rajendra K.Singh +2 位作者 Varsha Sagar Jung‑Hwan Lee Hae‑Won Kim 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期127-179,共53页
Inflammatory skin disorders can cause chronic scarring and functional impairments,posing a significant burden on patients and the healthcare system.Conventional therapies,such as corticosteroids and nonsteroidal anti-... Inflammatory skin disorders can cause chronic scarring and functional impairments,posing a significant burden on patients and the healthcare system.Conventional therapies,such as corticosteroids and nonsteroidal anti-inflammatory drugs,are limited in efficacy and associated with adverse effects.Recently,nanozyme(NZ)-based hydrogels have shown great promise in addressing these challenges.NZ-based hydrogels possess unique therapeutic abilities by combining the therapeutic benefits of redox nanomaterials with enzymatic activity and the water-retaining capacity of hydrogels.The multifaceted therapeutic effects of these hydrogels include scavenging reactive oxygen species and other inflammatory mediators modulating immune responses toward a pro-regenerative environment and enhancing regenerative potential by triggering cell migration and differentiation.This review highlights the current state of the art in NZ-engineered hydrogels(NZ@hydrogels)for anti-inflammatory and skin regeneration applications.It also discusses the underlying chemo-mechano-biological mechanisms behind their effectiveness.Additionally,the challenges and future directions in this ground,particularly their clinical translation,are addressed.The insights provided in this review can aid in the design and engineering of novel NZ-based hydrogels,offering new possibilities for targeted and personalized skin-care therapies. 展开更多
关键词 Nanozymes HYDROGELS ROS scavenging ANTI-INFLAMMATION Skin regeneration
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ROS Balance Autoregulating Core-Shell CeO_(2)@ZIF-8/Au Nanoplatform for Wound Repair
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作者 Xi Zhou Quan Zhou +12 位作者 Zhaozhi He Yi Xiao Yan Liu Zhuohang Huang Yaoji Sun Jiawei Wang Zhengdong Zhao Xiaozhou Liu Bin Zhou Lei Ren Yu Sun Zhiwei Chen Xingcai Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期341-361,共21页
Reactive oxygen species(ROS)plays important roles in living organisms.While ROS is a double-edged sword,which can eliminate drug-resistant bacteria,but excessive levels can cause oxidative damage to cells.A core–shel... Reactive oxygen species(ROS)plays important roles in living organisms.While ROS is a double-edged sword,which can eliminate drug-resistant bacteria,but excessive levels can cause oxidative damage to cells.A core–shell nanozyme,Ce O_(2)@ZIF-8/Au,has been crafted,spontaneously activating both ROS generating and scavenging functions,achieving the multifaceted functions of eliminating bacteria,reducing inflammation,and promoting wound healing.The Au Nanoparticles(NPs)on the shell exhibit high-efficiency peroxidase-like activity,producing ROS to kill bacteria.Meanwhile,the encapsulation of Ce O_(2) core within ZIF-8 provides a seal for temporarily limiting the superoxide dismutase and catalase-like activities of Ce O_(2) nanoparticles.Subsequently,as the ZIF-8 structure decomposes in the acidic microenvironment,the Ce O_(2) core is gradually released,exerting its ROS scavenging activity to eliminate excess ROS produced by the Au NPs.These two functions automatically and continuously regulate the balance of ROS levels,ultimately achieving the function of killing bacteria,reducing inflammation,and promoting wound healing.Such innovative ROS spontaneous regulators hold immense potential for revolutionizing the field of antibacterial agents and therapies. 展开更多
关键词 Metal-organic framework(MOF) Reactive oxygen species(ROS) Cerium dioxide Au nanoparticles Wound healing
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Mesenchymal stem cell-derived small extracellular vesicles in the treatment of human diseases:Progress and prospect 被引量:9
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作者 Jie Shi Yu-Chen Zhao +5 位作者 Zhi-Fang Niu Hao-Jun Fan Shi-Ke Hou Xiao-Qin Guo Lu Sang Qi Lv 《World Journal of Stem Cells》 SCIE 2021年第1期49-63,共15页
Mesenchymal stem cells(MSCs)are self-renewing,multipotent cells that could differentiate into multiple tissues.MSC-based therapy has become an attractive and promising strategy for treating human diseases through immu... Mesenchymal stem cells(MSCs)are self-renewing,multipotent cells that could differentiate into multiple tissues.MSC-based therapy has become an attractive and promising strategy for treating human diseases through immune regulation and tissue repair.However,accumulating data have indicated that MSC-based therapeutic effects are mainly attributed to the properties of the MSC-sourced secretome,especially small extracellular vesicles(sEVs).sEVs are signaling vehicles in intercellular communication in normal or pathological conditions.sEVs contain natural contents,such as proteins,mRNA,and microRNAs,and transfer these functional contents to adjacent cells or distant cells through the circulatory system.MSC-sEVs have drawn much attention as attractive agents for treating multiple diseases.The properties of MSC-sEVs include stability in circulation,good biocompatibility,and low toxicity and immunogenicity.Moreover,emerging evidence has shown that MSC-sEVs have equal or even better treatment efficacies than MSCs in many kinds of disease.This review summarizes the current research efforts on the use of MSC-sEVs in the treatment of human diseases and the existing challenges in their application from lab to clinical practice that need to be considered. 展开更多
关键词 Mesenchymal stem cells Small extracellular vesicles EXOSOMES Human diseases THERAPEUTICS PROSPECTS
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50 years of scanning electron microscopy of bone——a comprehensive overview of the important discoveries made and insights gained into bone material properties in health,disease,and taphonomy 被引量:2
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作者 Furqan A.Shah Krisztina Ruscsák Anders Palmquist 《Bone Research》 SCIE CAS CSCD 2019年第2期123-137,共15页
Bone is an architecturally complex system that constantly undergoes structural and functional optimisation through renewal and repair.The scanning electron microscope (SEM) is among the most frequently used instrument... Bone is an architecturally complex system that constantly undergoes structural and functional optimisation through renewal and repair.The scanning electron microscope (SEM) is among the most frequently used instruments for examining bone.It offers the key advantage of very high spatial resolution coupled with a large depth of field and wide field of view.Interactions between incident electrons and atoms on the sample surface generate backscattered electrons,secondary electrons,and various other signals including X-rays that relay compositional and topographical information.Through selective removal or preservation of specific tissue components (organic,inorganic,cellular,vascular),their individual contribution(s) to the overall functional competence can be elucidated.With few restrictions on sample geometry and a variety of applicable sample-processing routes,a given sample may be conveniently adapted for multiple analytical methods.While a conventional SEM operates at high vacuum conditions that demand clean,dry,and electrically conductive samples,non-conductive materials (e.g.,bone) can be imaged without significant modification from the natural state using an environmental scanning electron microscope.This review highlights important insights gained into bone microstructure and pathophysiology,bone response to implanted biomaterials,elemental analysis,SEM in paleoarchaeology,3D imaging using focused ion beam techniques,correlative microscopy and in situ experiments.The capacity to image seamlessly across multiple length scales within the meso-micro-nano-continuum,the SEM lends itself to many unique and diverse applications,which attest to the versatility and user-friendly nature of this instrument for studying bone.Significant technological developments are anticipated for analysing bone using the SEM. 展开更多
关键词 SCANNING electron MICROSCOPY COMPREHENSIVE OVERVIEW important discoveries
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Applications of human hepatitis B virus preS domain in bio-and nanotechnology 被引量:2
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作者 Riki Toita Takahito Kawano +1 位作者 Jeong-Hun Kang Masaharu Murata 《World Journal of Gastroenterology》 SCIE CAS 2015年第24期7400-7411,共12页
Human hepatitis B virus(HBV) is a member of the family Hepadnaviridae, and causes acute and chronic infections of the liver. The hepatitis B surface antigen(HBs Ag) contains the large(L), middle(M), and small(S) surfa... Human hepatitis B virus(HBV) is a member of the family Hepadnaviridae, and causes acute and chronic infections of the liver. The hepatitis B surface antigen(HBs Ag) contains the large(L), middle(M), and small(S) surface proteins. The L protein consists of the S protein, pre S1, and pre S2. In HBs Ag, the pre S domain(pre S1 + pre S2) plays a key role in the infection of hepatocytic cells by HBV and has several immunogenic epitopes. Based on these characteristics of pre S, several pre S-based diagnostic and therapeutic materials and systems have been developed. Pre S1-specific monoclonal antibodies(e.g., MA18/7 and KR127) can be used to inhibit HBV infection. A myristoylated pre S1 peptide(amino acids 2-48) also inhibits the attachment of HBV to Hepa RG cells, primary human hepatocytes, and primary tupaia hepatocytes. Antibodies and antigens related to the components of HBs Ag, pre S(pre S1 + pre S2), or pre S1 can be available as diagnostic markers of acute and chronic HBV infections. Hepatocyte-targeting delivery systems for therapeutic molecules(drugs, genes, or proteins) are very important for increasing the clinical efficacy of these molecules and in reducing their adverse effects on other organs. The selective delivery of diagnosticmolecules to target hepatocytic cells can also improve the efficiency of diagnosis. In addition to the full-length HBV vector, pre S(pre S1 + pre S2), pre S1, and pre S1-derived fragments can be useful in hepatocyte-specific targeting. In this review, we discuss the literature concerning the applications of the HBV pre S domain in bio- and nanotechnology. 展开更多
关键词 HEPATITIS B virus HEPATOCYTE deliverysystem VACCINE HEPATITIS B surface ANTIGEN Diagnosis
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Effect of colouring green stage zirconia on the adhesion of veneering ceramics with different thermal expansion coefficients 被引量:2
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作者 Guliz Aktas Erdal Sahin +2 位作者 Pekka Vallittu Mutlu zcan Lippo Lassila 《International Journal of Oral Science》 SCIE CAS CSCD 2013年第4期236-241,共6页
This study evaluated the adhesion of zirconia core ceramics with their corresponding veneering ceramics, having different thermal expansion coefficients (TECs), when zirconia ceramics were coloured at green stage. Z... This study evaluated the adhesion of zirconia core ceramics with their corresponding veneering ceramics, having different thermal expansion coefficients (TECs), when zirconia ceramics were coloured at green stage. Zirconia blocks (N=240; 6 mm x 7 mm x 7 mm) were manufactured from two materials namely, ICE Zirconia (Group 1) and Prettau Zirconia (Group 2). In their green stage, they were randomly divided into two groups. Half of the specimens were coloured with colouring liquid (shade A2), Three different veneering ceramics with different TEC (ICE Ceramic, GC Initial Zr and IPS e.max Ceram) were fired on both coloured and non-coloured zirconia cores. Specimens of high noble alloys (Esteticor Plus) veneered with ceramic (VM 13) (n= 16) acted as the control group. Core-veneer interface of the specimens were subjected to shear force in the Universal Testing Machine (0.5 mm-min-1). Neither the zirconia core material (P=0.318) nor colouring (P=0.188) significantly affected the results (three-way analysis of variance, Tukey's test). But the results were significantly affected by the veneering ceramic (P=0.000). Control group exhibited significantly higher mean bond strength values (45.7__.8) MPa than all other tested groups ((27.1__.4.1)-(39.7__.4.7) and (27.4__.5.6)-(35.9___4.7) MPa with and without colouring, respectively) (P^0.001). While in zirconia-veneer test groups, predominantly mixed type of failures were observed with the veneering ceramic covering ~ 1/3 of the substrate surface, in the metal-ceramic group, veneering ceramic was left adhered 1/3 of the metal surface. Colouring zirconia did not impair adhesion of veneering ceramic, but veneering ceramic had a significant influence on the core-veneer adhesion. Metal-ceramic adhesion was more reliable than all zirconia-veneer ceramics tested. 展开更多
关键词 ADHESION bond strength colouring~ thermal expansion coefficient ZIRCONIA
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Fermentation of mulberry leaves with Cordyceps militaris enhanced anti-adipogenesis activity in 3T3-L1 cells through down-regulation of PPAR-γ pathway signaling 被引量:3
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作者 Lu Guo Jum Soon Kang +4 位作者 Young Hoon Park Beong Il Je Dae Youn Hwang Woo Hong Joo Young Whan Choi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第12期557-565,共9页
Objective:To establish an efficacious and efficient fermentation method of enhancing the anti-adipogenesis effect of mulberry(Morus alba) leaves using Cordyceps militais.Methods:Dried mulberry leaves,dried mulberry le... Objective:To establish an efficacious and efficient fermentation method of enhancing the anti-adipogenesis effect of mulberry(Morus alba) leaves using Cordyceps militais.Methods:Dried mulberry leaves,dried mulberry leaves with50% raw silkworm pupa and raw silkworm pupa were fermented with Cordyceps militais for 4 weeks at 25℃,after which the dried mulberry leaves and fermented product were extracted with 70%ethanol and subjected to high performance liquid chromatography(HPLC).The contents of cordycepin,pelargonidin,chlorogenic acid,iso-quercetin and caffeic acid were determined.We then used the 3 T3-L1 cells to investigate whether extracts of fermentation enhanced anti-adipogenesis activity in vitro.Results:HPLC showed that fermentation changed the contents of cordycepin,pelargonidin,chlorogenic acid,iso-quercetin and caffeic acid.Furthermore,fermented dried mulberry leaves with 50% raw silkworm pupa had a better efficacy of anti-adipogenesis than dried mulberry leaves,fermented dried mulberry leaves and fermented silkworm pupa and inhibited triglycerides accumulation and glucose consumption.Additionally,fermented dried mulberry leaves with50% raw silkworm pupa inhibited PPAR-γ signaling.Conclusions:Fermentation with Cordyceps militaris enhanced antiadipogenesis efficacy of mulberry leaves. 展开更多
关键词 DRIED FERMENTATION SILKWORM
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Reduced Ti-MOFs encapsulated black phosphorus with high stability and enhanced photocatalytic activity 被引量:2
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作者 Xiao Liu Peijie Fan +3 位作者 Liangping Xiao Jian Weng Qingchi Xu Jun Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期185-191,I0007,共8页
The generation of green hydrogen(H_2) energy is of great significance to solve worldwide energy and environmental issues. Reduced Ti based photocatalyst has recently attracted intensive attention due to its excellent ... The generation of green hydrogen(H_2) energy is of great significance to solve worldwide energy and environmental issues. Reduced Ti based photocatalyst has recently attracted intensive attention due to its excellent photocatalytic activity, while the synthesis of reduced Ti based photocatalysts with high stability is still a great challenge. Here, we report a facile method for synthesis of reduced Ti metal organic frameworks(small amounts of Pt incorporated) encapsulated BP(BP/R-Ti-MOFs/Pt) hybrid nanomaterial with enhanced photocatalytic activity. The strong interaction between Ti and P reduces the valence state of the binding Ti^(4+)on the BP surface, forming abundant reduced Ti^(4+)within R-Ti-MOFs/BP. Such reduced Ti^(4+)render R-Ti-MOFs/BP efficient charge transfer and excellent light absorption capability, thus promote the photocatalytic H_2 production efficiency. Furthermore, the Ti-P interaction stabilizes both reduced Ti^(4+)and BP during the photocatalytic reaction, which greatly enhanced the stability of the obtained BP/R-TiMOFs/Pt photocatalyst. 展开更多
关键词 2D materials Reduced Ti-MOFs Black phosphorus Photocatalysis Solar-to-hydrogen conversion Metal-organic frameworks
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Axial compressive behavior of Moso Bamboo and its components with respect to fiber-reinforced composite structure 被引量:1
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作者 Xuexia Zhang Zixuan Yu +2 位作者 Yan Yu Hankun Wang Jinghao Li 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2371-2377,共7页
Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell matrix.We conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions o... Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell matrix.We conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions of the culm.The apparent Young’s modulus and compressive strength of whole thickness bamboo blocks exhibited slight increases with increasing height along the culm,due to slight increases of fiber volume fraction(Vf)from 28.4 to 30.4%.Other blocks showed a significant increase in apparent Young’s modulus and strength from the inner to outer part of the culm wall,mainly owing to a sharp increase of Vf from 17.1 to 59.8%.With a decrease of fiber fraction volume there was a transition from relatively brittle behavior to very ductile behavior in bamboo blocks.Results indicated that stiffness and strength of bamboo was primarily due to fiber in compression,and ductility of bamboo was provided by the parenchyma cell matrix acting as a natural fiber-reinforced composite. 展开更多
关键词 BAMBOO AXIAL COMPRESSIVE behavior Functionally GRADE STRUCTURE
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The journey of multifunctional bone scaffolds fabricated from traditional toward modern techniques 被引量:2
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作者 Ashkan Bigham Firoozeh Foroughi +3 位作者 Erfan Rezvani Ghomi Mohammad Rafienia Rasoul Esmaeely Neisiany Seeram Ramakrishna 《Bio-Design and Manufacturing》 SCIE CSCD 2020年第4期281-306,共26页
As a bone scaffold,meeting all basic requirements besides dealing with other bone-related issues-bone cancer and accelerated regeneration-is not expected from traditional scaffolds,but a newer class of scaffolds calle... As a bone scaffold,meeting all basic requirements besides dealing with other bone-related issues-bone cancer and accelerated regeneration-is not expected from traditional scaffolds,but a newer class of scaffolds called multifunctional.From a clinical point of view,being a multifunctional scaffold means reducing in healing time,direct costs-medicine,surgery,and hospitalization-and indirect costs-loss of mobility,losing job,and pain.The main aim of the present review is following the multifunctional bone scaffolds trend to deal with both bone regeneration and cancer therapy.Special consideration is given to different fabrication techniques which have been applied to yield these materials spanning from traditional to modern ones.Moreover,the hierarchical structure of bone plus bone cancers and available medicines to them are introduced to familiarize the potential reader of review with the pluri-disciplinary essence of the field.Eventually,a brief discussion relating to the future trend of these materials is provided. 展开更多
关键词 Multifunctional scaffolds Bone cancer Fabrication techniques Bone tissue regeneration
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Extracellular matrix based biomaterials for central nervous system tissue repair: the benefits and drawbacks 被引量:1
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作者 Sarka Kubinova 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第9期1430-1432,共3页
Functional repair of injured tissue in the adult central nervous system (CNS) still remains a big challenge for current biomed- ical research and its upcoming clinical translation. The axonal regeneration of the adu... Functional repair of injured tissue in the adult central nervous system (CNS) still remains a big challenge for current biomed- ical research and its upcoming clinical translation. The axonal regeneration of the adult CNS is generally low, and it is addi- tionally restricted after injury by the presence of inhibitory mol- ecules, generated by the glial scar. 展开更多
关键词 ECM the benefits and drawbacks Extracellular matrix based biomaterials for central nervous system tissue repair
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Fracture resistance of posterior teeth restored with modern restorative materials 被引量:1
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作者 Ibrahim M. Hamouda Salah H. Shehata 《The Journal of Biomedical Research》 CAS 2011年第6期418-424,共7页
We studied the fracture resistance of maxillary premolars restored with recent restorative materials. Fifty maxillary premolars were divided into five groups: Group 1 were unprepared teeth; Group 2 were teeth prepare... We studied the fracture resistance of maxillary premolars restored with recent restorative materials. Fifty maxillary premolars were divided into five groups: Group 1 were unprepared teeth; Group 2 were teeth prepared without restoration; Group 3 were teeth restored with tetric ceram HB; Group 4 were teeth restored with InTen S; and Group 5 were teeth restored with Admira. The samples were tested using a universal testing machine. Peak loads at fracture were recorded. The teeth restored with Admira had the highest fracture resistance followed by those restored with InTen-S and tetric ceram HB. Prepared, unrestored teeth were the weakest group. There was a significant difference between the fracture resistance of intact teeth and the prepared, unrestored teeth. There was also a significant difference among the tested restorative materials. Teeth restored with Admira showed no significant difference when compared with the unprepared teeth. It was concluded that the teeth restored with Admira exhibited the highest fracture resistance. 展开更多
关键词 fracture resistance composite resin adhesives mesio-occlusal-distal (MOD) cavities
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Effect of vitamin D3 on production of progesterone in porcine granulosa cells by regulation of steroidogenic enzymes 被引量:1
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作者 So-Hye Hong Jae-Eon Lee +7 位作者 Hong Sung Kim Young-Jin Jung DaeYoun Hwang Jae Ho Lee Seung Yun Yang Seung-Chul Kim Seong-Keun Cho Beum-Soo An 《The Journal of Biomedical Research》 CAS CSCD 2016年第3期203-208,共6页
1,25-dihydroxyvitamin D3 (VD3), an active form of Vitamin D, is photosynthesized in the skin of vertebrates in response to solar ultraviolet B radiation (UV-B). VD3 deficiency can cause health problems such as imm... 1,25-dihydroxyvitamin D3 (VD3), an active form of Vitamin D, is photosynthesized in the skin of vertebrates in response to solar ultraviolet B radiation (UV-B). VD3 deficiency can cause health problems such as immune disease, metabolic disease, and bone disorders. It has also been demonstrated that VD3 is involved in reproductive functions. Female sex hormones such as estrogen and progesterone are biosynthesized mainly in ovarian granulosa cells as the ovarian follicle develops. The functions of sex hormones include regulation of the estrus cycle and puberty as well as maintenance of pregnancy in females. In this study, we isolated granulosa cells from porcine ovaries and cultured them for experiments. To examine the effects of VD3 on ovarian granulosa cells, the mRNA and protein levels of genes were analyzed by Real-time PCR and Western blotting assay. Production of progesterone from granulosa cells was also measured by ELISA assay. As a result, transcriptional and translational regulation of progesterone biosynthesis-related genes in granulosa cells was significantly altered by VD3. Furthermore, progesterone concen- trations in porcine granulosa cell-cultured media decreased in response to VD3. These results show that VD3 was a strong regulator of sex steroid hormone production in porcine granulosa cells, suggesting that vitamin D deficiency may result in inappropriate sexual development of industrial animals and eventually economic loss. 展开更多
关键词 Vitamin D3 steroidogenesis PROGESTERONE granulosa cell PIG
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Role of spleen tyrosine kinase in liver diseases 被引量:1
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作者 Dhadhang Wahyu Kurniawan Gert Storm +1 位作者 Jai Prakash Ruchi Bansal 《World Journal of Gastroenterology》 SCIE CAS 2020年第10期1005-1019,共15页
Spleen tyrosine kinase (SYK),a non-receptor tyrosine kinase,is expressed in most hematopoietic cells and non-hematopoietic cells and play a crucial role in both immune and non-immune biological responses.SYK mediate d... Spleen tyrosine kinase (SYK),a non-receptor tyrosine kinase,is expressed in most hematopoietic cells and non-hematopoietic cells and play a crucial role in both immune and non-immune biological responses.SYK mediate diverse cellular responses via an immune-receptor tyrosine-based activation motifs (ITAMs)-dependent signalling pathways,ITAMs-independent and ITAMs-semidependent signalling pathways.In liver,SYK expression has been observed in parenchymal (hepatocytes) and non-parenchymal cells (hepatic stellate cells and Kupffer cells) and found to be positively correlated with the disease severity.The implication of SYK pathway has been reported in different liver diseases including liver fibrosis,viral hepatitis,alcoholic liver disease,non-alcoholic steatohepatitis and hepatocellular carcinoma.Antagonism of SYK pathway using kinase inhibitors have shown to attenuate the progression of liver diseases thereby suggesting SYK as a highly promising therapeutic target.This review summarizes the current understanding of SYK and its therapeutic implication in liver diseases. 展开更多
关键词 Spleen tyrosine kinase Liver diseases INFLAMMATION Targeted therapeutics Spleen tyrosine kinase inhibitors
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Synthesis of Biphasic Calcium Phosphate by Hydrothermal Route and Conversion to Porous Sintered Scaffold 被引量:1
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作者 Sunarso   Ahmad Fauzi Mohd Noor +3 位作者 Shah Rizal Kasim Radzali Othman Ika Dewi Ana Kunio Ishikawa 《Journal of Biomaterials and Nanobiotechnology》 2013年第3期273-278,共6页
Biphasic calcium phosphate (BCP) consisting of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) was successfully synthesized by new hydrothermal route using β-TCP as precursor. The X-ray diffraction analysis ... Biphasic calcium phosphate (BCP) consisting of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) was successfully synthesized by new hydrothermal route using β-TCP as precursor. The X-ray diffraction analysis of as-synthesized powder indicated that β-TCP had been transformed into HA phase and amount of HA formed gradually increased with prolonged time. The results revealed that the recent technique may be able to control the composition of the obtained BCP which would influence the bioresorbability. Porous body of BCP was prepared by impregnation of polymeric sponge template with the slurry of the powder followed by sintering. The X-ray diffraction of porous product revealed that the composition of β-TCP increased after sintering indicating that HA had been decomposed. Porous BCP obtained from the recent technique possessed both macro and micropores structure which are useful for rapid tissue formation. Besides, the recent porous fabrication technique yielded porous BCP which preserved the sponge template morphology, enabling it to fabricate porous material with controlled pores structure. 展开更多
关键词 BIPHASIC Calcium PHOSPHATE Β-TCP HYDROXYAPATITE HYDROTHERMAL Porous
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Bone Remodeling, Biomaterials And Technological Applications: Revisiting Basic Concepts 被引量:2
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作者 Patricia C.Salgado Plinio C.Sathler +9 位作者 Helena C.Castro Gutemberg G.Alves Aline M.de Oliveira Rodrigo Cde Oliveira Monica D.C.Maia Carlos R.Rodrigues Paulo G.Coelho Andre Fuly Lúcio M.Cabral Jose M.Granjeiro 《Journal of Biomaterials and Nanobiotechnology》 2011年第3期318-328,共11页
Presently, several different graft materials are employed in regenerative or corrective bone surgery. However current misconceptions about these biomaterials, their use and risks may compromise their correct applicati... Presently, several different graft materials are employed in regenerative or corrective bone surgery. However current misconceptions about these biomaterials, their use and risks may compromise their correct application and development. To unveil these misconceptions, this work briefly reviewed concepts about bone remodeling, grafts classification and manufacturing processes, with a special focus on calcium phosphate materials as an example of a current employed biomaterial. Thus a search on the last decade was performed in Medline, LILACS, Scielo and other scientific electronic libraries using as keywords biomaterials, bone remodeling, regeneration, biocompatible materials, hydroxyapatite and therapeutic risks. Our search showed not only an accelerated biotechnological development that brought significant advances to biomaterials use on bone remodeling treatments but also several therapeutic risks that should not be ignored. The biomaterials specificity and limitations to clinical application point to the current need for developing safer products with better interactions with the biological microenvironments. 展开更多
关键词 Biocompatible materials Bone remodeling HYDROXYAPATITE Therapeutic risks
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Mechanical Behaviour of Composite Bioactive Bone Cements Consisting of Two Different Types of Surface Treated Hydroxyapatite as Filler
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作者 S Deb JA Roether 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期10-12,共3页
Bioactive bone cements based on a paste-paste system for orthopaedic applications were developed consisting of hydroxyapatite ( HA ) filler panicles in a methacrylate matrix comprising urethane dimethacrylate ( UD... Bioactive bone cements based on a paste-paste system for orthopaedic applications were developed consisting of hydroxyapatite ( HA ) filler panicles in a methacrylate matrix comprising urethane dimethacrylate ( UDMA ) and triethylene glycol dimethacrylate ( TEGDMA ). To improve the interface between inorganic filler and organic matrix the HA panicles were subjected to two different surface treatment methods, using polyacrylic acid (PAA) and γ-methacryloxy propyl trimethoxy silane (γMPS). The aim of the present study was to determine the influence of surface treatment and the inclusion of multifunctional methacrylates on the mechanical properties, namely 3-point flexural strength (FS) and fracture toughness of the cements and the effect of ageing in simulated body fluid. Comparing the mechanical properties of the two cements, the γMPS- HA cement showed that the fracture toughness of the experimental bone cements were significantly greater ( p 〈 0.001) compared to that of the PMMA cement, whereas PAA-HA containing cement had strength vollues around 20% lower. Interestingly, PAA was found to be more effective in improving the interface as the PAA treated HA cement ( UTHAPPA ) maintained its strength on immersion in SBF, suggesting that PAA provided a coupling, which was less sensitive to moisture, a similar trend was also observed with the inclusion of the carboxyl containing multifunctional methacrylates. 展开更多
关键词 bioactive bone cements coupling agents COMPOSITES polyacrylic acid
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Mechanical characterization of Pinus massoniana cell walls infected by blue-stain fungi using in situ nanoindentation
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作者 Jing Li Yan Yu +1 位作者 Chao Feng Hankun Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期661-665,共5页
Characterizing the mechanical properties of wood cell walls will lead to better understanding and optimization of modifications made to wood infected by the blue-stain fungi.In this study,in situ nanoindentation was u... Characterizing the mechanical properties of wood cell walls will lead to better understanding and optimization of modifications made to wood infected by the blue-stain fungi.In this study,in situ nanoindentation was used to characterize the mechanical properties of the cell walls of Pinus massoniana infected by blue-stain fungi at the cellular level.The results show that in situ nanoindentation is an effective method for this purpose and that blue-stain fungi penetrate wood structures and degrade wood cell walls,significantly reducing the mechanical properties of the cell walls.The method can also be used to evaluate and improve the properties of other wood species infected by blue-stain fungi. 展开更多
关键词 Blue-stain NANOINDENTATION Cell wall Pinus massoniana Mechanical properties
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