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71.
Ahmad Jalloh Antwoine Flowers Charles Hudson Dale Chaput Jennifer Guergues Stanley M. Stevens Jr. Paula C. Bickford 《International journal of molecular sciences》2021,22(12)
Microglial activity in the aging neuroimmune system is a central player in aging-related dysfunction. Aging alters microglial function via shifts in protein signaling cascades. These shifts can propagate neurodegenerative pathology. Therapeutics require a multifaceted approach to understand and address the stochastic nature of this process. Polyphenols offer one such means of rectifying age-related decline. Our group used mass spectrometry (MS) analysis to explicate the complex nature of these aging microglial pathways. In our first experiment, we compared primary microglia isolated from young and aged rats and identified 197 significantly differentially expressed proteins between these groups. Then, we performed bioinformatic analysis to explore differences in canonical signaling cascades related to microglial homeostasis and function with age. In a second experiment, we investigated changes to these pathways in aged animals after 30-day dietary supplementation with NT-020, which is a blend of polyphenols. We identified 144 differentially expressed proteins between the NT-020 group and the control diet group via MS analysis. Bioinformatic analysis predicted an NT-020 driven reversal in the upregulation of age-related canonical pathways that control inflammation, cellular metabolism, and proteostasis. Our results highlight salient aspects of microglial aging at the level of protein interactions and demonstrate a potential role of polyphenols as therapeutics for age-associated dysfunction. 相似文献
72.
Zahid Hanif Zeeshan Ahmad Khan Dongho Shin Dongwhi Choi Sung Jea Park 《大分子材料与工程》2021,306(10):2100289
Cellulose nanocrystals (CNCs) incorporated with silver nanoparticles (AgNPs) photonic films have drawn considerable attention due to their plasmonic chiroptical activity. However, the exploitation of some fundamental properties for practical use such as the affinity analysis of metal nanoparticles attached to the surface of photonic films according to the solvent compatibility and antibacterial activity under physical conditions has yet not been studied. Hence, a facile process of in situ deposition of AgNPs into the chiral structure of CNC films is proposed. CNC photonic films, cross-linked by glutaraldehyde are prepared. This interaction generated the solvents-stable photonic film with a considerable amount of unreacted aldehyde functional groups that facilitates the reduction of Ag salt to AgNPs. The formed AgNPs in the photonic films show excellent stability over immersion in various polar and non-polar solvents. The post-solvent treated photonic films display excellent contact-based antibacterial behavior against gram-negative Escherichia coli. 相似文献
73.
Weldalite 050, a high-strength Al-Mg-Li alloy, was evaluated for its corrosion resistance in deaerated and air saturated Arabian
Gulf water to determine its suitability for marine applications. Weight loss and electrochemical studies showed that the alloy
had minimum corrosion rates of 1.82 and 4.82 mpy (mils per year), respectively, in deaerated and air saturated Arabian Gulf
water with very high total dissolved solids (TDS) content. Weldalite 050 exhibited good resistance to corrosion at velocities
up to 3.9 m/s. The formation of Al2MgLi, Al-Li, Al12Mg17, and Al-Li precipitates has a pronounced effect on its corrosion resistance. The corrosion resistance of Weldalite 050 compares
favorably with that of alloys 5052 and 5054, wrought alloys 6061 and 6013, and silicon carbide (SiC) reinforced alloys 6061
and 6013. 相似文献
74.
M. S. Ahmad M. U. Ahmad A. A. Ansari S. M. Osman 《European Journal of Lipid Science and Technology》1978,80(9):353-354
Seeds from seven species of plants belonging to less familiar botanical families were analysed for oil and protein, and the fatty acid composition of the oils was determined by gas liquid chromatography. Oils from five species are interesting in containing high percentage (71.9–83.7%) of C18 unsaturated acids. Seeds from Tropaeolum majus contain oil which, on the basis of chromatographic analysis, appears to be a suitable industrial source of cis-11-eicosenoic and cis-13-docosenoic (erucic) acids. 相似文献
75.
Radiation-induced wood plastic composites (WPC) were prepared from five varieties of Bangladeshi timbers, using seven different types of monomers. The mixtures of double and triple monomers were investigated along with the single-monomer system for the preparation of composites. Among the three systems, single-monomer process showed the highest polymer loading with butylmethacrylate (BMA). Tensile strength (TS) property, represented as Tf = TSwpc/TSwood was determined. Highest Tf values were achieved with the soft wood. The effects of dose and dose rate, monomer concentration, and swelling agent were also studied. Suitable total dose was found to be 3 Mrad at 0.8 Mrad/h, and methanol exhibited the best swelling ability for the woods at a ratio of 1 : 9 v/v in all the monomer investigated. 相似文献
76.
M. U. Ahmad S. K. Husain S. M. Osman 《Journal of the American Oil Chemists' Society》1981,58(6):673-674
Seed oil ofPhyllanthus niruri (Euphorbiaceae) contains 1.2% ricinoleic (12-hydroxy-cis-9-octadecenoic) acid, previously unknown in the genusPhyllanthus. Identification is based on thin layer and gas liquid chromatography, infrared, nuclear magnetic resonance, and mass spectrometry
analysis as well as chemical methods. Other major components of the oil are linoleic acid (21%) and linolenic acid (51.4%).
Presented at the ISF/AOCS World Congress, April 1980, New York City. 相似文献
77.
M. U. Ahmad A. A. Ansari S. M. Osman 《European Journal of Lipid Science and Technology》1980,82(3):106-109
The reactions of 1,2-hexadecanediol and 1,2-octadecanediol with hydrogen bromide in the presence of acetic anhydride have been investigated. The treatment of hydrogen bromide (48%) in acetic anhydride with 1,2-hexadecanediol gives mainly 1-bromo-2-acetoxy hexadecane (66%), 2-acetoxy hexadecanol (26%), and 1,3-hexadecanediol (8%). Similar products result from 1,2-octadecanediol. The structures of the products are based on combustion data, spectroscopic, and chemical evidences. The mechanism of the reaction has been discussed. 相似文献
78.
Ambient‐cured polyesteramide (APEA) coating resin synthesized from dihydroxy fatty amide obtained from linseed oil, a sustainable resource, and poly(styrene‐co‐maleic anhydride), a bifunctional acid component, was found to exhibit improved physicomechanical and anticorrosive properties. The structural elucidation of APEA resin has been carried out by FTIR, 1H‐NMR, and 13C‐NMR spectroscopies. The physicomechanical and chemical resistance properties were investigated by standard methods. The corrosion resistance performance was evaluated in acid, alkali, and organic solvent. The thermal behavior was studied by TGA technique. A comparative study of these properties of APEA with reported baked polyesteramide (PEA) coatings was carried out. A remarkable improvement in the drying property of APEA was observed. The APEA coatings also showed improved physicomechanical and anticorrosive properties as compared to the baked PEA coatings. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1818–1824, 2005 相似文献
79.
In the past two decades, piezoelectric ceramic/polymer composites with different connectivities have been developed for transducer applications such as hydrophones, biomedical imaging, nondestructive testing, and air imaging. Recently, much attention has been given to fine-scale piezoelectric ceramic/polymer composites. These composites allow higher operating frequencies, and thus increased resolution, in medical imaging transducers. In this review, methods for processing fine-scale piezoelectric ceramic/polymer composites are discussed. The current capabilities, strengths, and weaknesses of each method are compared. The importance of spatial scale in composite performance is also reviewed. Several of the processing methods have demonstrated composites with fine-scale ceramic phases (<50 μm), and others have potential to form composites with a ceramic scale of under 20 μm. 相似文献
80.
M. Bilal Banaras Khan H.A. Rahnamaye Aliabad M. Maqbool S. Jalai Asadabadi I. Ahmad 《Computer Physics Communications》2014
Thermoelectric properties of two antiperovskites SbNCa3 and BiNCa3 are calculated using first principles calculations. High values of Seebeck coefficients are observed for these materials. Electrical and thermal conductivities are also calculated. Increase in thermal conductivity and decrease in electrical conductivity are found with increasing temperature. The maximum values of thermal conductivity are 92×1014 W/m K s and 88×1014 W/m K s for SbNCa3 and BiNCa3 respectively at a temperature of 900 K. The peak values of 5×1020/Ω m s and 5.2×1020/Ω m s are achieved for n-type SbNCa3 and BiNCa3 respectively at a temperature of 300 K. Figure of merit is achieved for these materials at room temperature which shows that these materials can be useful for thermoelectric devices and alternative energy sources. 相似文献