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Adipose tissue-derived mesenchymal stem cells and chitosan/poly(vinyl alcohol)nanofibrous scaffolds for cartilage tissue engineering

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Cell Regeneration 2020年第1期9卷 62-73页

作者： Ghada Nour-Eldeen mazen Abdel-Rasheed Amira m.EL-Rafei Osama Azmy Gehan T.El-Bassyouni molecular Genetics and Enzymology Department National Research CentreDokkiCairo 12622Egypt Stem Cell Research group Medical Research Centre of ExcellenceNational Research CentreCairo 12622Egypt Reproductive Health Research Department National Research Centre33 El-Buhouth StDokkiCairo 12622Egypt Refractories Ceramics and Building Materials DepartmentNational Research CentreDokkiCairo 12622Egypt

Osteoarthritis(OA)has been defined as a chronic inflammatory joint disease characterized by progressive articular cartilage *** growing interest in regenerative medicine,using cell therapy and tissue engineering,where cellular components in combination with engineered scaffolds and bioactive materials were used to induce functional tissue *** the present study,nanofibrous scaffold based on chitosan(CS)/poly(vinyl alcohol)(PVA)were used to develop biologically functionalized biomaterial to mimic the extracellular matrix,allowing the human adipose tissue derived mesenchymal stem cells(ADSCs)to proliferate and differentiate to chondrogenic *** morphology of the nanofibrous mat was examined using field emission scanning electron microscope(FE/SEm).The characteristic functional groups and the nature of the chemical bonds between atoms were evaluated using Fourier transform infrared spectroscopy(FTIR)*** of the seeded cells was morphologically evaluated by scanning electron microscopy and by flow cytometry for the expression of the stem cell surface *** differentiation potential was verified after chondrogenic induction by analyzing the expression of chondrogenic marker genes using real-time(RT PCR).Current study suggest significant potential for the use of ADSCs with the nanofibrous scaffolds in improving the osteoarthritis pathology.

关键词： Adipose tissue mesenchymal stem cells Nanofibrous scaffolds Osteoarthritis Cartilage tissue engineering

New Azomethine Compounds on the Basis <i>m</i>-Phenylenediamine and Substituted Benzaldehydes Capable of Oxidative Polymerization

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Open Journal of Polymer Chemistry 2018年第2期8卷 34-39页

作者： T. A. Borukaev A. m. mazloeva R. m. R. m. Otarova Yu. A. malkanduev A. Kh. malamatov A. V. Orlov Kabardino-Balkar State University (Named after H. m. Berbekov) Nalchik Russia A.V.Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow Russia

Low-temperature condensation of m-phenylene diamine and various aromatic aldehydes (benzaldehyde, m-, o-nitrobenzaldehyde, p-diethylaminobenzaldehyde, o-, p-hydroxybenzaldehyde and 4-hydroxy-3,5-ditert-butylbenzaldehyde) in the ethyl alcohol medium synthesized new azomethine compounds. With the help of spectral methods and elemental analysis, the structure of the azomethine compounds obtained was confirmed. It was founded that irradiation of azomethine compounds with UV light at a wavelength of 300 - 330 nm results in their emission. The luminescent properties of the resulting compounds are due to the presence of chromophore azomethine groups in the molecule structure. In particular, the π-electrons of the azomethine bonds can undergo irradiation to a different energy levels, accompanied by fluorescence. It was shown that synthesized azomethine compounds are capable of oxidative polymerization. Based on azomethine compounds in hydrochloric acid solution synthesized polymers with conjugated bonds, which had low molecular-mass characteristics. It is shown that the oxidative polymerization of azomethines proceeds through a slow (one-electron transfer) and rapid (recombination of the radical cations) stage.

关键词： Azomethine Compounds Synthesis Luminescence Oxidative Polymerization

正常乳腺的mR扩散加权成像:表观扩散系数的可重复性及月经周期及绝经期的变化的研究

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国际医学放射学杂志 2012年第5期 497-497页

作者： E.A.m.O'Flynn V.A.morgan S.L.Giles N.m.deSouza 王梅 Clinical magnetic Resonance Group Cancer Research UK and ESPSRC Cancer Imaging CentreDowns RoadSuttonSurreyUK SM2 5PT

摘要目的研究正常乳腺腺体组织的表观扩散系数(ADC)测量的可重复性以及月经周期及绝经期乳腺组织ADC值的变化。方法31名志愿者(13个绝经前,18个绝经后)进行两次磁共振扩散加权序列扫描(间隔11～22d),计算ADC总和灌注不敏感的ADC高(忽略b... 详细信息

摘要目的研究正常乳腺腺体组织的表观扩散系数(ADC)测量的可重复性以及月经周期及绝经期乳腺组织ADC值的变化。方法31名志愿者(13个绝经前,18个绝经后)进行两次磁共振扩散加权序列扫描(间隔11～22d),计算ADC总和灌注不敏感的ADC高(忽略b=0),对观察者多次重复测量及不同观察者间的平均ADC值的一致性进行评估,并且评价月经周期和绝经后两个阶段乳腺组织的平均ADC值的变化。

关键词：扩散加权成像 mRI 表观扩散系数纤维腺体组织乳腺

Combining Hydraulic and Phosphate bonds to Improve Properties of Alumina-spinel Low Cement Castables

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China's Refractories 2009年第2期18卷 12-18页

作者： m. Paghandeh A. monshi R. Emadi Department of materials Engineering Isfahan University of Technology (IUT)

A basic alumina -spinel low cement castables （ castables A） and another castables （ castables B） with 5% addition of sodium hexametaphosphate were prepared and heat treated at 110 ℃, 900℃ and 1 400 ℃. It is shown that after heat treating at 110 ℃ , cold crushing strength （CCS） of castables B is more than 3 times of castables A and apparent porosity （ AP ） is less than half of castables A. The presence of mg2P207 and AIPO4 · 2H2O is the main difference. At 800- 1 000 ℃ that hydraulic bond reverses to dehydrate condition and castables A becomes weak with high porosity, castables B shows a CCS more than 4 times of castables A. Needles of magnesium phosphate are responsible for reinforcing microstructure of castables B at 900 ℃. After firing at 1 400 ℃, castables B shows extra ordinary CCS of more than 100 mPa. Reasons were discussed with X-ray diffraction and scanning electron microscopy.

关键词： Sintering mechanical properties Alumina Castables Phosphate bonds

Sino-Pakistani Relations In a Changing World

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Beijing Review 2006年第23期49卷 60-61页

作者： JAmSHED AYAZ KHAN m. RAmZAN ALI former president of the Institute of Regional Studies (IRS) Islamabad a research analyst at the IRS

Pakistan and China share strong common bonds of history, culture and geography Every time we went to China we witnessed a different country, given its sustained development. China is building everywhere, or rather it is rebuilding at an amazing rate that has not been equaled anywhere except perhaps in Europe, rising from the ashes of the Second World War.

关键词： Sino-Pakistani Relations In a Changing World

Nanomaterials in Biomedicine

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Soft Nanoscience Letters 2015年第3期5卷 53-54页

作者： mosaad A. Abdel-Wahhab Francisco márquez Food Toxicology & Contaminants Department National Research Center Dokki Cairo Egypt Nanomaterials Research Group-NRG School of Natural Sciences and Technology University of Turabo Gurabo Puerto Rico USA

Nowadays, nanomaterials have become an emerging field that has shown great promise in the development of novel diagnostic, imaging and therapeutic agents for a variety of diseases, including cancer, due to their nanoscale size effects and increased surface area. In comparison to their larger counterparts, nanomaterials have unique physicochemical and biological properties including size, shape, chemical composition, surface structure and charge, aggregation and agglomeration, and solubility which can affect their interactions with biomolecules and cells. Nanoparticles (NPs) with size-tunable light emission have demonstrated an impressive potential as high-efficiency delivery transporters for biomolecules into cells, being used to produce exceptional images of tumor sites. moreover, NPs delivery system has been widely applied in pharmaceutical field to enhance absorption of bioactive compounds since they can interact with several phytochemicals by hydrogen bonds and hydrophobic interactions to encapsulate these phytochemicals in NPs and thus enhance aqueous solubility of the chemicals. moreover, NPs also can prevent against oxidation/degradation of the phytochemicals encapsulated in the gastrointestinal tract and can be taken directly up by epithelial cells in the small intestine resulting in the increase of absorption and bioavailability of phytochemicals. In general, there are two specific fields of utilization of intrinsically active NPs as pharmacologic agents including oxidative-related pathologies and cancer. On the other hand, Redox active NPs have been shown to ameliorate many clinically relevant pathological disorders that implicate oxidative stress, reducing the oxidative burden and alleviating many important symptoms. Such NPs act either in a catalytic way resembling the action of antioxidant enzymes such as catalase and superoxide dismutase, or as activating surfaces to facilitate reactions between the aqueous environment and the reactive oxygen species p

关键词： Nanomaterials Biomedicine

Particle Size and Crystal Phase Effects in Fischer-Tropsch Catalysts

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Engineering 2017年第4期3卷 467-476页

作者： Jin-xun Liu Peng Wang Wayne Xu Emiel J. m. Hensen Laboratory of Inorganic materials Chemistry Schuit Institute of Catalysis Department of Chemical Engineering and Chemistry Eindhoven University of Technology Eindhoven 5600 MB The Netherlands National Institute of Clean-and-Low-Carhon Energy Beijing 102211 China

Fischer-Tropsch synthesis （FTS） is an increasingly important approach for producing liquid fuels and chemicals via syngas-that is, synthesis gas, a mixture of carbon monoxide and hydrogen-generated from coal, natural gas, or biomass. In FTS, dispersed transition metal nanoparticles are used to catalyze the reactions underlying the formation of carbon-carbon bonds. Catalytic activity and selectivity are strongly correlated with the electronic and geometric structure of the nanoparticles, which depend on the particle size, morphology, and crystallographic phase of the nanoparticles. In this article, we review recent works dealing with the aspects of bulk and surface sensitivity of the FTS reaction. Understanding the different catalytic behavior in more detail as a function of these parameters may guide the design of more active, selective, and stable FTS catalysts.

关键词： Fischer-Tropsch synthesis Iron cobalt and ruthenium carbides Size effect Crystal structure

Hydrothermal Fabrication of Rod-like Rutile Nano-Particles

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厦门大学学报（自然科学版） 2002年第S1期41卷 112-页

作者： José m F Ferreira Department of Ceramics and Glass Engineering

Rutile phase exhibits higher refractive index and h id ing power, good chemical stability, and is becoming a candidate material for the high-temperature separation and catalysis applications. The thermodynamically stable feature of rutile among the three polymorphs of TiO 2 usually hinders ob taining nano-sized rutile phase by a conventional calcining way. However, acid peptization of amorphous TiO 2 is favorable to the formation of rutile phase. I n this work, well-crystallized and well-dispersed rod-like rutile particles w ith specific surface areas of 49.1 and 35.0 m 2/g were prepared by hydrothermal ly treating the acid peptized TiO 2 amorphous sols at relatively low temperatur es of 200 ℃ or 240 ℃, respectively. The formation of non-touching rutile part icles is attributed to high long-range electrostatic forces between particles i n the presence of the high concentration of the peptizer. The acid peptization w ould easily break the ≡Ti-O-Ti≡ bonds to form ≡Ti-OH or HO-Ti-OH species depending on the amount of acid, and create conditions for the formation of rut ile nuclei after structural rearrangements.

关键词： TiO Hydrothermal Fabrication of Rod-like Rutile Nano-Particles

瞬间性视网膜缺血重新灌注对大鼠视网膜细胞凋亡的影响

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中华眼底病杂志 2000年第3期16卷 207-207页

作者：周跃华 Luther E.Lindner George C.Y.Chiou Kimberly P.morgan 李志辉北京同仁医院眼科 100730 College of medicine TEXASA&m University

我们以升高眼压的方法造成视网膜瞬间缺血重新灌注的动物模型,对瞬间性视网膜缺血重新灌注所引起的视网膜细胞凋亡及其相应的一些改变进行研究.

关键词：视网膜缺血细胞凋亡大鼠再灌注损伤