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131.
Zonghua Pu Qian Liu Abdullah M. Asiri Xuping Sun 《Journal of Applied Electrochemistry》2014,44(11):1165-1170
In this communication, we demonstrate the preparation of Ni nanoparticles-graphene hybrid film via simultaneous electrochemical reduction of graphene oxide and Ni2+ on conductive substrate for the first time. We further show the utilization of such hybrid film as an efficient oxygen evolution reaction electrocatalyst with highly catalytic activity and good durability. 相似文献
132.
Akon Higuchi Qing-Dong Ling S. Suresh Kumar Yung Chang Ta-Chun Kao Murugan A. Munusamy Abdullah A. Alarfaj Shih-Tien Hsu Akihiro Umezawa 《Progress in Polymer Science》2014
The physical and chemical characteristics of biomaterial surface and hydrogels can be altered by external stimuli, such as light irradiation, temperature changes, pH shifts, shear stress forces, electrical forces, and the addition of small chemical molecules. Such external stimulus-responsive biomaterials represent promising candidates that have been developed for the culture and differentiation of embryonic stem (ES) cells, induced pluripotent stem (iPS) cells, and adult stem cells. Biomaterials that are designed to respond in a reversible manner to specific external signals can be formed on micropatterned or non-micropatterned surface, in hydrogels, or on microcarriers. Stem cells and the cells differentiated from them into specific tissue lineages can be cultured and/or differentiated on dishes with immobilized external stimulus-responsive polymers. Cells can be detached from these dishes without using an enzymatic digestion method or a mechanical method when the appropriate external stimulus is generated on the surface. This review discusses the polymers and polymeric designs employed to produce surface and hydrogels for stem cell culture, differentiation, and/or cell detachment using various external stimuli. 相似文献
133.
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
134.
Abdullah Y. Hassan Sairah Yousaf Moran R. Levin Osamah J. Saeedi Saima Riazuddin Janet L. Alexander Zubair M. Ahmed 《International journal of molecular sciences》2022,23(1)
Congenital cataracts (CC) are responsible for approximately one-tenth of childhood blindness cases globally. Here, we report an African American family with a recessively inherited form of CC. The proband demonstrated decreased visual acuity and bilateral cataracts, with nuclear and cortical cataracts in the right and left eye, respectively. Exome sequencing revealed a novel homozygous variant (c.563A > G; p.(Asn188Ser)) in GJA3, which was predicted to be pathogenic by structural analysis. Dominantly inherited variants in GJA3 are known to cause numerous types of cataracts in various populations. Our study represents the second case of recessive GJA3 allele, and the first report in African Americans. These results validate GJA3 as a bona fide gene for recessively inherited CC in humans. 相似文献
135.
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
136.
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
137.
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
138.
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
139.
Optimization of Enzymatic Process Condition for Protein Enrichment,Sugar Recovery and Digestibility Improvement of Soy Flour 下载免费PDF全文
Soy protein is a valuable nutritional supplement for food and animal feed. While protein constitutes ~50 % of defatted soy flour (SF), it coexists with complex carbohydrates (30–35 %) which may have anti‐nutritional effects. An enzymatic process can remove the carbohydrate and produce protein‐enriched soy products. The hydrolysate with monomerized carbohydrates is valuable fermentation feedstock. In this study, Aspergillus niger and Trichoderma reesei enzymes were compared for use in the process. Effects of pH (3.2–6.4), temperature (40–60 °C), enzyme‐to‐SF ratio (0–2 ml/g) and SF loading (150–350 g/l) were evaluated for the enzymatic conversion of SF carbohydrate to reducing sugar (YRS) and total soluble carbohydrate (YTC) in the hydrolysate. Effects of these single factors and interactions between factors were investigated. Optimal pH and temperature were similar for both enzymes: pH 4.8 and 50–51 °C for YTC, and pH 5.1–5.2 and 48–51 °C for YRS. The two enzymes also gave similar protein contents in resultant soy protein concentrates, i.e., 74–75 % with 2 ml/g enzyme broth and 150 g/l SF, which were higher than the 64–68 % protein in commercial concentrates. A. niger enzyme was significantly more effective in carbohydrate conversion, achieving YRS = 75 % and YTC = 78 % with 2 ml/g enzyme and 150 g/l SF, higher than the YRS (30 %) and YTC (64 %) obtained with T. reesei enzyme. Monomerization was essentially complete in hydrolysate produced with A. niger enzyme. 相似文献
140.
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