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91.
Alesh Kumar Ashwani Mittal Avik Das Debasis Sen C.R. Mariappan 《Ceramics International》2021,47(3):3586-3596
In this work improved electroactive mesoporous Ag-doped bio-ceramics for medical usages are developed, examining their structural, electrical, in-vitro bioactivity, cell cultures and antibacterial properties against various classical pathogenic bacteria. Ag-containing mesoporous bio-ceramics (MBCs): xmol%Ag2O - (100-x)[45.8CaO-8.4B2O3-45.8SiO2] where x = 2, 5, 7.5 and 10 were synthesized through a sol-gel method. The small angle X-ray scattering and electron microscopy studies reveal the embedment of silver nanoparticles in the samples. Existence of silver as Ag+/Ag0 forms in the samples is confirmed by X-ray photoelectron spectroscopy. The N2 adsorption-desorption analysis evidence the mesoporous structure of the samples. The electrical conductivity of samples increases from 5.4 x 10?8 S cm?1 for x = 2 to 1.9 x 10?6 S cm?1 for x = 7.5 and then decreases to 0.9 x 10?6 S cm?1 for x = 10 at 110 °C. In vitro bioactivity studies revealed that Ag-containing MBCs hold the bone-like hydroxyapatite formation after immersion in human blood plasma like-solution such as Dulbecco's Modi?ed Eagle's Medium. The antibacterial effect of samples against pathogenic bacteria (S. aureus, E. coli, P. monas aeruginosa, and B. cereus) increases with Ag concentration (x = 7.5) and then decreases with Ag content (x = 10). Antibacterial effect is greater for the sample with high electrical conductivity. The cell culture studies evidence not considerable cytotoxic effects for Ag-containing MBCs. Finally, the C2C12 myoblast cell culture studies reveal the significant cell growths and differentiation (myogenesis) for high electrical conducting Ag-containing MBCs. 相似文献
92.
Dr. Richa Sharma Tulika Srivastava Alka Raj Pandey Dr. Tripti Mishra Dr. Bhagyashri Gupta Dr. Sabbu Sathish Reddy Dr. Suriya P. Singh Dr. Tadigoppula Narender Aradhya Tripathi Dr. Balasubramanian Chandramouli Dr. Koneni V. Sashidhara Dr. Smriti Priya Dr. Niti Kumar 《ChemMedChem》2021,16(13):2146-2156
Defective protein folding and accumulation of misfolded proteins is associated with neurodegenerative, cardiovascular, secretory, and metabolic disorders. Efforts are being made to identify small-molecule modulators or structural-correctors for conformationally destabilized proteins implicated in various protein aggregation diseases. Using a metastable-reporter-based primary screen, we evaluated pharmacological chaperone activity of a diverse class of natural products. We found that a flavonoid glycoside ( C-10 , chrysoeriol-7-O-β-D-glucopyranoside) stabilizes metastable proteins, prevents its aggregation, and remodels the oligomers into protease-sensitive species. Data was corroborated with additional secondary screen with disease-specific pathogenic protein. In vitro and cell-based experiments showed that C-10 inhibits α-synuclein aggregation which is implicated in synucleinopathies-related neurodegeneration. C-10 interferes in its structural transition into β-sheeted fibrils and mitigates α-synuclein aggregation-associated cytotoxic effects. Computational modeling suggests that C-10 binds to unique sites in α-synuclein which may interfere in its aggregation amplification. These findings open an avenue for comprehensive SAR development for flavonoid glycosides as pharmacological chaperones for metastable and aggregation-prone proteins implicated in protein conformational diseases. 相似文献
93.
Wireless Personal Communications - Authentication is a term very important for data communication security. We see many frauds due to authentication failure. The problem manifolds when... 相似文献
94.
Wireless Networks - In this paper, the concept of mantle cloaking method uses to enhance the isolation between the two electrically close dipole antenna at low-terahertz (THz) frequencies, two... 相似文献
95.
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97.
Mallikarjuna A. Kumar N. Suresh Babu T. Anil Ramesh S. Naidu K. Chandra Babu 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(12):4512-4522
Journal of Inorganic and Organometallic Polymers and Materials - (1-x) (Al0.2La0.8TiO3)?+?(x) (BiZnFeO3) (x?=?0.2–0.8) [ALTBZFO] nanocomposites were synthesized via... 相似文献
98.
Silicon - This work presents the analog and RF performance evaluation of Junctionless Accumulation Mode (JAM) Gate Stack Gate All Around (GS-GAA) FinFET, and the results acquired have been compared... 相似文献
99.
Santanu Mandal Vijay Kishore Madhuparna Bose Samit Kumar Nandi Mangal Roy 《材料科学技术学报》2021,84(25):159-172
In recent years,iron(Fe)based degradable metal is explored as an alternative to permanent fracture fixation devices.In the present work,copper(Cu)is added in Fe-Mn system to enhance the degradation rate and antimicrobial properties.Fe-Mn-xCu(x=0.9,5 and 10 wt.%)alloys are prepared by the melting-casting-forging route.XRD analysis confirms austenite phase stabilization due to the presence of Mn and Cu.As predicted by Thermo-Calc calculations,Cu rich phase precipitations are noticed along the austen-ite grain boundaries.Degradation behaviours of Cu added Fe-Mn alloys are investigated through static immersion and electrochemical polarization where enhanced degradation is found for higher Cu added alloys.When challenged against E.Coli bacteria,the Fe-Mn-Cu alloy media extract shows a significant bac-tericidal effect compare to the base alloy.In vitro cytocompatibility studies,as determined using MG63 and MC3T3-E1 cell lines,indicate increased cell density as a function of time for all the alloys.When implanted in rabbit femur,the newly developed alloy does not show any kind of tissue necrosis around the implants.Better osteogenesis and higher new bone formation are observed with Fe-Mn-10Cu alloy as evident from micro-computed tomography(μ-CT)and fluorochrome labelling. 相似文献
100.
Wireless Personal Communications - Internet of Things (IoT) is one of the emerging technologies, which is widely used across the globe. As the idea of a smart city was founded, IoT has been... 相似文献