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71.
72.
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
73.
Shadpour Mallakpour Mohammad Zhiani Abdolvahid Barati Hussein Rostami 《International Journal of Hydrogen Energy》2013
The present investigation deals with the fabrication of new poly(vinyl alcohol)/titanium dioxide (PVA/TiO2) nanocomposites (NCs) with different titanium dioxide (TiO2) loading by using ultrasound irradiation. For the improvement of nanoparticles (NPs) dispersion and increasing possible interactions between NPs and PVA, the surface of TiO2 NPs was modified by γ-aminopropyltriethoxy silane. The as-prepared NCs were characterized by spectroscopic, thermogravimetric analysis and electron microscopy methods. The results demonstrate that NPs dispersed homogeneously within the PVA matrix on nanoscale, which could be assigned to the hydrogen and covalent bonds formed between PVA and NPs. The results indicated that heat stability of NCs was improved in the presence of modified TiO2 NPs. The mechanisms of surface modification and a possible mechanism of ultrasonic induced interaction between polymer and NPs have been analyzed. 相似文献
74.
Qusai M. Mistarihi Wooseong Park Kyungseok Nam Mohd‐Syukri Yahya Yonghee Kim Ho Jin Ryu 《国际能源研究杂志》2018,42(6):2141-2151
In this paper, the fabrication of novel burnable absorber fuel concepts with oxide pellets, containing either a lumped Gd2O3 rod, a mini‐pellet, or a spherical particle in the centerline of the oxide pellet, is investigated to propose the lumped Gd2O3 burnable absorber fuel concept to improve nuclear fuel performance with longer fuel cycle lengths and better fuel utilization. The unique characteristic of the lumped Gd2O3 burnable absorber fuel is its high spatial self‐shielding factor that reduces its burnout rate and, therefore, improves the reactivity control. Oxide pellets containing lumped Gd2O3 were fabricated by using a combination of cold isostatic pressing and microwave sintering at 1500°C to understand the potential technical issues in the fabrication of duplex burnable absorber fuel. The effect of the sintering temperature on the densification and phase transformation of 8 wt.% yttria‐stabilized zirconia, a surrogate for UO2, was investigated. Spherical Gd2O3 particles were fabricated by the drip casting of a Gd2O3‐based Na alginate solution. The fabrication of duplex oxide pellets by using presintered Gd2O3 mini‐pellets resulted in internal cracks at the interface between the Gd2O3 and 8 wt.% yttria‐stabilized zirconia layers because of the mismatch of their densification. However, the formation of interfacial cracks was eliminated by controlling the initial sintered density of the lumped Gd2O3. 相似文献
75.
Shih Yeh Lim Mohd Sokhini Abdul Mutalib Sui Kiat Chang 《International Journal of Food Properties》2018,21(1):2428-2451
There is a growing concern over the food safety issue related to increased incidence of cooking oil adulteration with recycled cooking oil (RCO). The objective of this study was to detect fresh palm olein (FPO) adulteration with RCO using fatty acid composition (FAC) and Fourier-transform infrared spectroscopy (FTIR) spectral analyses combined with chemometrics. RCO prepared in the laboratory was mixed with FPO in the proportion ranged from 1% to 50% (v/v) to obtain the adulterated oil samples (AO). FACs for FPO, RCO, and AO were determined using gas chromatography equipped with a flame ionization detector (GC-FID). The compositions of most fatty acids in RCO lied within the normal ranges of Codex standard, except for C8:0, C10:0, C11:0, C15:0, trans C18:1, and polyunsaturated fatty acids (PUFAs), C20:5. PUFAs showed a consistent decreasing trend with increasing magnitude of change with respect to increasing adulteration level and thus might be a good indicator for detecting FPO adulteration with RCO. The evaluation parameters (coefficient of determination, root mean standard error) of the FTIR-partial least square (PLS) model of palm oil adulteration with recycled oil are R2 = 0.995 and 3.25, respectively. For FTIR spectral analysis, the distinct variations in spectral regions and aberrations in characteristic bands between FPO and RCO were observed. The optimized PLS calibration model developed from normal spectral of the combined region at 3602–3398, 3016–2642, and 1845–650 cm?1 overpredict the adulteration level. On the other hand, the discriminant analysis classification model was able to classify the FPO and AO into two distinct groups. Improvement of the principles of combined techniques in authenticating AO from fresh oil is beneficial as a guideline to detect adulteration in cooking oil. 相似文献
76.
Kong Fei Chai Noranizan Mohd Adzahan Roselina Karim Yaya Rukayadi 《International Journal of Food Properties》2018,21(1):1091-1106
Rambutan seed is discarded during fruit processing. However, the seed contains a considerable amount of crude fat. Hence, the objective of this study was to determine two anti-nutritional constituents, namely saponin and tannin, and to characterize the fat of the seeds of 11 varieties of rambutan fruit. Results showed that the range of crude fat content is fairly narrow (36.13–39.13 g/100 g dried seeds). The iodine value and free fatty acid content of the fat were 38.50–50.61 g I2/100 g fat and 0.99–2.18% as oleic acid, respectively. Oleic (33.35–46.64%) and arachidic (26.03–33.27%) acids were the main fatty acids in the fat. HPLC analysis showed that the fat comprised mainly five unknown triacylglycerols (83.94–95.33%). The melting and crystallization curves showed that the fat exhibited four to nine non-distinct peaks. The complete melting and crystallization onset temperatures of the fat were 24.8–50.6°C and 24.1–39.4°C, respectively, while the melting and crystallization enthalpies of the fat ranged from 71.2 to 141.7 J/g and from 60.4 to 88.9 J/g, respectively. At 0°C, the solid fat index of the fat ranged between 87.4% and 91.6% and the fats of some varieties melted completely at human body temperature. The saponin and tannin contents of the seed were 14.27–18.96 mg soya saponin/100 g and 4.40–26.68 mg catechin equivalent/100 g, respectively. Findings showed that rambutan seed fat has potential to be used in various sectors of food industry. 相似文献
77.
Khalili Amelia Ahmad Mohamed Zaharuddin Basri Mohd Ariffanan Mohd 《Microsystem Technologies》2019,25(10):3765-3777
Microsystem Technologies - In this paper a robust backstepping sliding mode controller is developed for tracking control of 2-DOF piezo-actuated micromanipulation system. The control approach is... 相似文献
78.
Maktabdar Oghaz Mahdi Maarof Mohd Aizaini Rohani Mohd Foad Zainal Anazida Shaid Syed Zainudeen Mohd 《Neural computing & applications》2019,31(6):1835-1853
Neural Computing and Applications - Texture analysis is devised to address the weakness of color-based image segmentation models by considering the statistical and spatial relations among the group... 相似文献
79.
Multimedia Tools and Applications - Distortion classification is an important step in blind image quality assessment. In this paper, a new image distortion classification algorithm is presented.... 相似文献