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排序方式: 共有2059条查询结果,搜索用时 11 毫秒
71.
Hussein Farah Susanne N. Wijesinghe Thomas Nicholson Fawzeyah Alnajjar Michelangelo Certo Abdullah Alghamdi Edward T. Davis Stephen P. Young Claudio Mauro Simon W. Jones 《International journal of molecular sciences》2022,23(6)
Changes in cellular metabolism have been implicated in mediating the activated fibroblast phenotype in a number of chronic inflammatory disorders, including pulmonary fibrosis, renal disease and rheumatoid arthritis. The aim of this study was therefore to characterise the metabolic profile of synovial joint fluid and synovial fibroblasts under both basal and inflammatory conditions in a cohort of obese and normal-weight hip OA patients. Furthermore, we sought to ascertain whether modulation of a metabolic pathway in OA synovial fibroblasts could alter their inflammatory activity. Synovium and synovial fluid was obtained from hip OA patients, who were either of normal-weight or obese and were undergoing elective joint replacement surgery. The synovial fluid metabolome was determined by 1H NMR spectroscopy. The metabolic profile of isolated synovial fibroblasts in vitro was characterised by lactate secretion, oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) using the Seahorse XF Analyser. The effects of a small molecule pharmacological inhibitor and siRNA targeted at glutaminase-1 (GLS1) were assessed to probe the role of glutamine metabolism in OA synovial fibroblast function. Obese OA patient synovial fluid (n = 5) exhibited a different metabotype, compared to normal-weight patient fluid (n = 6), with significantly increased levels of 1, 3-dimethylurate, N-Nitrosodimethylamine, succinate, tyrosine, pyruvate, glucose, glycine and lactate, and enrichment of the glutamine–glutamate metabolic pathway, which correlated with increasing adiposity. In vitro, isolated obese OA fibroblasts exhibited greater basal lactate secretion and aerobic glycolysis, and increased mitochondrial respiration when stimulated with pro-inflammatory cytokine TNFα, compared to fibroblasts from normal-weight patients. Inhibition of GLS1 attenuated the TNFα-induced expression and secretion of IL-6 in OA synovial fibroblasts. These findings suggest that altered cellular metabolism underpins the inflammatory phenotype of OA fibroblasts, and that targeted inhibition of glutamine–glutamate metabolism may provide a route to reducing the pathological effects of joint inflammation in OA patients who are obese. 相似文献
72.
Kunal Biswas Awdhesh Kumar Mishra Pradipta Ranjan Rauta Abdullah G. Al-Sehemi Mehboobali Pannipara Avik Sett Amra Bratovcic Satya Kumar Avula Tapan Kumar Mohanta Muthupandian Saravanan Yugal Kishore Mohanta 《International journal of molecular sciences》2022,23(2)
At present, the potential role of the AgNPs/endo-fullerene molecule metal nano-composite has been evaluated over the biosystems in-vitro. The intra-atomic configuration of the fullerene molecule (C60) has been studied in-vitro for the anti-proliferative activity of human breast adenocarcinoma (MDA-MB-231) cell lines and antimicrobial activity against a few human pathogens that have been augmented with the pristine surface plasmonic electrons and antibiotic activity of AgNPs. Furthermore, FTIR revealed the basic vibrational signatures at ~3300 cm−1, 1023 cm−1, 1400 cm−1 for O-H, C-O, and C-H groups, respectively, for the carbon and oxygen atoms of the C60 molecule. NMR studies exhibited the different footprints and magnetic moments at ~7.285 ppm, explaining the unique underlying electrochemical attributes of the fullerene molecule. Such unique electronic and physico-chemical properties of the caged carbon structure raise hope for applications into the drug delivery domain. The in-vitro dose-dependent application of C60 elicits a toxic response against both the breast adenocarcinoma cell lines and pathogenic microbes. That enables the use of AgNPs decorated C60 endo fullerene molecules to design an effective anti-cancerous drug delivery and antimicrobial agent in the future, bringing a revolutionary change in the perspective of a treatment regime. 相似文献
73.
S. M. Mahfuzul Islam Abdullah A. Loman Qian Li Lu-Kwang Ju 《Journal of the American Oil Chemists' Society》2020,97(9):963-975
The enzymatic treatment of defatted soy flour (SF) to reduce indigestible carbohydrates can result in undesirable protein loss. Here protein loss was minimized with quantitation of the effects of ionic strength (IS), protease activity, and SF toasting. At the enzyme processing condition (25% w/v SF, 50 °C, pH 4.8, 48 hours), protein loss increased linearly with the IS in enzyme broths (EB); e.g., contacting untoasted SF with water or heat-deactivated EB showed protein loss of 28% in water but up to 40% when IS was increased in the range of 0.04–0.19 M. Protein loss also increased with protease in EB (nondeactivated): after adjusted for IS-related loss, approximately 10% and 25% additional protein loss occurred in EB of 73 and 490–557 U/(g SF) protease, respectively. SDS-PAGE results showed that proteolysis was not extensive, mainly on β-conglycinin α'/α and glycinin acidic 37-kDa subunits; and most of the proteolytic products could be recovered by heat-induced precipitation. SF toasting effects were studied, particularly at 2-hours 160°C, with material balances, protein distributions, and monosaccharide yields in hydrolysates. Overall, protein loss was minimized to 5.2% and the conversion of carbohydrate to monomeric sugars increased to 89.2%. 相似文献
74.
Abdullah Ameen Saad Hassan Wasi Khan Shahid Husain Pooja Dhiman Mahavir Singh 《International Journal of Applied Ceramic Technology》2020,17(5):2430-2438
In this work, the physical properties of nanocrystalline samples of La0.7Sr0.3Mn1−xFexO3 (0.0 ≤ x ≤ 0.20) perovskite manganites synthesized by the reverse micelle (RM) technique were explored in detail. The phase purity, crystal structure, and crystallite size of the samples were determined using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. All the samples had rhombohedral crystal structure and crystallite size increased with increase in Fe content in La0.7Sr0.3MnO3. The scanning electron micrographs (SEMs) exhibited smooth surface morphology and nonuniform shape of the particles. The optical properties studied using UV-visible absorption spectroscopy revealed a decrease in the absorbance and optical band gap with an increase in Fe content in La0.7Sr0.3MnO3 compound. The temperature-dependent resistivity measurements revealed semiconducting nature of x = 0 and 0.1 samples up to the studied temperature range, while a metal-to-insulator transition was observed at higher Fe doping. Magnetic studies revealed weak ferromagnetism in all the samples and a reduction in the maximum magnetization with an increase in Fe content. A close correlation between electrical transport and magnetic properties was observed with the doping of Fe ion in La0.7Sr0.3MnO3 at Mn site. These results advocate strong interactions associated with the double exchange mechanism among Fe3+ and Mn3+ ions. 相似文献
75.
Prof. Amarajothi Dhakshinamoorthy Assoc. Prof. Sergio Navalón Prof. Abdullah M. Asiri Prof. Hermenegildo Garcia 《ChemMedChem》2020,15(23):2236-2256
Confinement of Au nanoparticles (NPs) within the porous materials with few nanometers (2-3 nm) has been a well established research area in the past decades in heterogeneous catalysis mainly due to the unique behaviour of Au NPs than its bulk counterpart. In this aspect, Au NPs encapsulated within the pore volumes of metal−organic frameworks (MOFs) have been intensively explored as heterogeneous solid catalysts for wide range of reactions. In recent years, Au NPs confined within the porous MOFs along with the photosensitizer or drug have been effectively used for the treatment of tumor cells through the generation of reactive oxygen species via cascade reactions. This work highlights the benefits of MOFs pores in the preparation of nanomedicine with high efficiency by assembling Au NPs, photosensitizer/drug with the combination of laser either for imaging or treatment of tumor cells. Further, the existing literature is grouped based on the nature of porous materials employed in the preparation of nanomedicine. The final section comments on our view on future developments in the field. 相似文献
76.
Correct Prediction of the Vibration Behavior of a High Power Ultrasonic Transducer by FEM Simulation
Amir Abdullah Abbas Pak 《The International Journal of Advanced Manufacturing Technology》2008,39(1-2):21-28
This paper presents a study on three types of finite element analyses of high power ultrasonic transducer by using the finite element commercial software called ANSYS. The transducer geometry was treated as a 2D axi- symmetric model, 3D quart and full 3D model. For all of the simulations the modeled transducer was used in modal analysis and harmonic solutions to understand its mechanical behavior and its natural frequency. A comparison was made between each type of modeling and experimental results. This comparison allows the parameters of FEM models to be iteratively adjusted and optimized and also leads to selection of the best modeling type. The achieved FEM results exhibited a remarkably high predictive potential of ANSYS in modeling and simulation and allowed control on the design and on the vibration behavior of the high power ultrasonic transducer. 相似文献
77.
Chien Hwa Chong Chung Lim Law Michael Cloke Luqman Chuah Abdullah Wan Ramli Wan Daud 《Drying Technology》2013,31(10):1286-1293
Sun drying of chempedak (Artocarpus integer) was carried out on different sample sizes to investigate the effects on product quality. Fick's second law model was used to determine the effective diffusivities of sun–dried chempedak slabs based on the drying rate versus moisture content plots. In addition, texture degradation and total color changes were investigated. The texture and color changes of dried chempedak were relatively significant (p < 0.05) compared to fresh chempedak. There was an increase in dried fruit hardness and chewiness but a decrease in springiness and cohesiveness during drying. 相似文献
78.
Noriah Bidin Siti Radhiana Azni Shumaila Islam Mundzir Abdullah M. Fakaruddin Sidi Ahmad Ganesan Krishnan A. Rahman Johari M. Aizat A. Bakar Nur Syahirah Sahidan NurFatin Musa M. Farizuddin Salebi Naqiuddin Razali Mohd Marsin Sanagi 《International Journal of Hydrogen Energy》2017,42(26):16325-16332
Hydrogen production via water electrolysis was studied under the effect of magnetic and optical field. A diode solid state laser at blue, green and red were utilized as optical field source. Magnetic bar was employed as external magnetic field. The green laser has shown a greatest effect in hydrogen production due to its non-absorbance properties in the water. Thus its intensity of electrical field is high enough to dissociation of hydronium and hydroxide ions during orientation toward polarization of water. The potential to break the autoprotolysis and generate the auto-ionization is the mechanism of optical field to reveal the hydrogen production in water electrolysis. The magnetic field effect is more dominant to enhance the hydrogen production. The diamagnetic property of water has repelled the present of magnetic in water. Consequently the water splitting occurs due to the repulsive force induced by the external magnetic field. The magnetic distributed more homogenous in the water to involve more density of water molecule. As a result hydrogen production due to magnetic field is higher in comparison to optical field. However the combination both fields have generated superior effect whereby the hydrogen yields nine times higher in comparison to conventional water electrolysis. 相似文献
79.
Jinxiu Wang Chunfeng Xue Zhangxiong Wu Wei Li Yingying Lv Abdullah M. Asiri Bo Tu Dongyuan Zhao 《Carbon》2012,50(7):2546-2555
An approach has been demonstrated for fabricating hollow micro-mesoporous carbon polyhedra by selective removal of the skeletal scaffolds of polyurethane (PU) foam in monolithic mesostructured resin/PU composites. Hollow micro-mesoporous carbon polyhedra with an irregular shape molded from the cellular cavities of PU foam were synthesized by using phenolic resol as a precursor, triblock copolymer Pluronic F127 as a template, PU foam as a skeletal scaffold and triethyl phosphate as a reaction agent. By a reaction with triethyl phosphate, the PU foam in resin/PU composites can be degraded, simultaneously leading to the disassembly of the monolithic structure into separated polyhedral particles. The method can also be used for synthesizing hollow micro-mesoporous carbon–silica polyhedra, using tetraethyl orthosilicate as a silica source. Moreover, after etching the silica away, hollow micro-mesoporous carbon polyhedra with an ordered hexagonal mesostructure (space group p6mm), large particle sizes of 65–500 μm, a large surface area of 1384 m2 g?1, a uniform pore size of 3.2 nm and a high pore volume of 1.15 cm3 g?1 as well as a high mesoporosity of 81% can be obtained, which exhibits excellent adsorption performance toward methylene blue compared with the active carbon having a similar surface area. 相似文献
80.
Alafara A. Baba Daud T. Olaoluwa Ayo F. Balogun Abdullah S. Ibrahim Fausat T. Olasinde Folahan A. Adekola 《Canadian Metallurgical Quarterly》2019,58(2):232-240
This study examines the extraction of beryllium and aluminium from a Nigerian beryl ore using Cyanex®272 in kerosene from an aqueous sulphate pregnant solution. Parameters such as extractant concentration and equilibrium pH that dictates the extraction yield were studied. Under the following conditions: temperature 27?±?2°C, phase ratio 1?1, about 45.50 and 46.76% of beryllium and aluminium were extracted by 0.15?mol?L?1 Cyanex®272 concentration within 30?min. However, the extraction yield of beryllium and aluminium was increased to 91.68% and 97.89% at equilibrium pH of 3 and 4, respectively, for beryllium and aluminium at 27?±?2°C. A 0.05?mol?L?1 H2SO4 solution was found to be adequate for the stripping of about 99.00% Be and 95.40% Al from the loaded organic phase. The pure solutions containing metal ions were accordingly beneficiated to obtain beryllium and aluminium compounds of industrial values. 相似文献