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51.
Sajadpour Maryam Abbasian Sara Siampour Hossein Bagheri Hasan Moshaii Ahmad 《Journal of Solid State Electrochemistry》2022,26(1):149-161
Journal of Solid State Electrochemistry - A facile and sensitive approach is introduced to precisely determine trace amounts of prostate specific antigen (PSA) by gold nanostructures deposited on... 相似文献
52.
Ghoorchian Arash Madrakian Tayyebeh Afkhami Abbas Bagheri Hasan 《Journal of Solid State Electrochemistry》2021,25(4):1217-1229
Journal of Solid State Electrochemistry - The increasing efforts devoted to fabricating electrochromic (EC) devices have motivated a lot of studies to develop new EC materials. Herein, we introduce... 相似文献
53.
Sangeeta Chandrashekar Raman Vijayakumar Ramachandran Chelliah Eric Banan-Mwine Daliri Inamul Hasan Madar Ghazala Sultan Momna Rubab Fazle Elahi Su-Jung Yeon Deog-Hwan Oh 《Molecules (Basel, Switzerland)》2021,26(7)
The study aimed to investigate the antibacterial activity of Mustard (Brassica juncea) and Moringa (Moringa oleifera) leaf extracts and coagulant protein for their potential application in water treatment. Bacterial cell aggregation and growth kinetics studies were employed for thirteen bacterial strains with different concentrations of leaf extracts and coagulant protein. Moringa oleifera leaf extract (MOS) and coagulant protein showed cell aggregation against ten bacterial strains, whereas leaf extract alone showed growth inhibition of five bacterial strains for up to 6 h and five bacterial strains for up to 3 h. Brassica juncea leaf extract (BJS) showed growth inhibition for up to 6 h, and three bacterial strains showed inhibition for up to 3 h. The highest inhibition concentration with 2.5 mg/mL was 19 mm, and furthermore, the minimum inhibitory concentration (MIC) (0.5 mg/mL) and MBC (1.5 mg/mL) were determined to have a higher antibacterial effect for <3 KDa peptides. Based on LCMS analysis, napin was identified in both MOS and BJS; furthermore, the mode of action of napin peptide was determined on lipoprotein X complex (LpxC) and four-chained structured binding protein of bacterial type II topoisomerase (4PLB). The docking analysis has exhibited moderate to potent inhibition with a range of dock score −912.9 Kcal/mol. Thus, it possesses antibacterial-coagulant potential bioactive peptides present in the Moringa oleifera purified protein (MOP) and Brassica juncea purified protein (BJP) that could act as an effective antimicrobial agent to replace currently available antibiotics. The result implies that MOP and Brassica juncea purified coagulant (BJP) proteins may perform a wide degree of antibacterial functions against different pathogens. 相似文献
54.
Mn-doped GaAs is studied with a real-space Hamiltonian on an fcc lattice that reproduces the valence bands of undoped GaAs. Large-scale Monte Carlo (MC) simulations on a Cray XT3, using up to a thousand nodes, were needed. Spin-orbit interaction and the random distribution of the Mn ions are considered. The hopping amplitudes are functions of the GaAs Luttinger parameters. At the realistic coupling J approximately 1.2 eV the MC Curie temperature and magnetization curves agree with experiments for x = 8.5% annealed samples. Mn-doped GaSb and GaP are also briefly discussed. 相似文献
55.
Ionic Liquids Supported on Metal‐Organic Frameworks: Remarkable Adsorbents for Adsorptive Desulfurization
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Dr. Nazmul Abedin Khan Zubair Hasan Prof. Dr. Sung Hwa Jhung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(2):376-380
Acidic ionic‐liquids (IL) supported on metal–organic frameworks (MOFs) have been shown to be beneficial for adsorptive desulfurization. A remarkable improvement in the adsorption capacity (ca. 71%) was observed in for ILs supported on MIL‐101 compared with virgin MIL‐101. The improved adsorptive performance might be explained by the acid–base interactions between the acidic ionic liquid and basic benzothiophene (BT). Moreover, from this study, it can be suggested that porous MOFs, supported with ionic liquids, may introduce a new class of highly porous adsorbents for the efficient adsorption of various compounds. 相似文献
56.
The efficacy of photodynamic therapy (PDT) using aminolevulinic acid (ALA), which is preferentially taken up by cancerous cells and converted to protoporphyrin IX (PpIX), can be substantially improved by pretreating the tumor cells with vitamin D (Vit D). Vit D is one of several “differentiation-promoting agents” that can promote the preferential accumulation of PpIX within the mitochondria of neoplastic cells, making them better targets for PDT. This article provides a historical overview of how the concept of using combination agents (“neoadjuvants”) for PDT evolved, from initial discoveries about neoadjuvant effects of methotrexate and fluorouracil to later studies to determine how vitamin D and other agents actually work to augment PDT efficacy. While this review focuses mainly on skin cancer, it includes a discussion about how these concepts may be applied more broadly toward improving PDT outcomes in other types of cancer. 相似文献
57.
Dr. Abshar Hasan Dr. Kyueui Lee Dr. Kunal Tewari Prof. Lalit M. Pandey Prof. Phillip B. Messersmith Prof. Karen Faulds Dr. Michelle Maclean Dr. King Hang Aaron Lau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5789-5793
Microbial surface attachment negatively impacts a wide range of devices from water purification membranes to biomedical implants. Mimics of antimicrobial peptides (AMPs) constituted from poly(N-substituted glycine) „peptoids“ are of great interest as they resist proteolysis and can inhibit a wide spectrum of microbes. We investigate how terminal modification of a peptoid AMP-mimic and its surface immobilization affect antimicrobial activity. We also demonstrate a convenient surface modification strategy for enabling alkyne–azide „click“ coupling on amino-functionalized surfaces. Our results verified that the N- and C-terminal peptoid structures are not required for antimicrobial activity. Moreover, our peptoid immobilization density and choice of PEG tether resulted in a „volumetric“ spatial separation between AMPs that, compared to past studies, enabled the highest AMP surface activity relative to bacterial attachment. Our analysis suggests the importance of spatial flexibility for membrane activity and that AMP separation may be a controlling parameter for optimizing surface anti-biofouling. 相似文献
58.
Hasan H. Hasanov Ivaylo K. Ivanov 《Phosphorus, sulfur, and silicon and the related elements》2020,195(10):858-870
AbstractWe report herein a study on the competitive electrophilic cyclization of 5-(dimethoxyphosphoryl)-alka-3,4-dienoates involving 5-endo-trig and 6-endo-trig mode cyclizations. Reaction with electrophiles produces mixtures of the 2-(2-oxo-2,5-dihydro-1,2-oxaphosphol-5-yl)-alkanoates and (6-oxo-5,6-dihydro-2H-pyran-2-yl)-phosphonates by competitive electrophilic cyclization due to the participation of the neighboring phosphonate and carboxylate groups. 相似文献
59.
Aye Ünlü Kerem Teral Zübeyde Uurlu Aydn Ali A. Dnmez Hasan Soliman Yusufolu hsan al 《Molecules (Basel, Switzerland)》2022,27(3)
Polygala species are frequently used worldwide in the treatment of various diseases, such as inflammatory and autoimmune disorders as well as metabolic and neurodegenerative diseases, due to the large number of secondary metabolites they contain. The present study was performed on Polygala inexpectata, which is a narrow endemic species for the flora of Turkey, and resulted in the isolation of nine known compounds, 6,3′-disinapoyl-sucrose (1), 6-O-sinapoyl,3′-O-trimethoxy-cinnamoyl-sucrose (tenuifoliside C) (2), 3′-O-(O-methyl-feruloyl)-sucrose (3), 3′-O-(sinapoyl)-sucrose (4), 3′-O-trimethoxy-cinnamoyl-sucrose (glomeratose) (5), 3′-O-feruloyl-sucrose (sibiricose A5) (6), sinapyl alcohol 4-O-glucoside (syringin or eleutheroside B) (7), liriodendrin (8), and 7,4′-di-O-methylquercetin-3-O-β-rutinoside (ombuin 3-O-rutinoside or ombuoside) (9). The structures of the compounds were determined by the spectroscopic methods including 1D-NMR (1H NMR, 13C NMR, DEPT-135), 2D-NMR (COSY, NOESY, HSQC, HMBC), and HRMS. The isolated compounds were shown in an in silico setting to be accommodated well within the inhibitor-binding pockets of myeloperoxidase and inducible nitric oxide synthase and anchored mainly through hydrogen-bonding interactions and π-effects. It is therefore plausible to suggest that the previously established anti-inflammatory properties of some Polygala-derived phytochemicals may be due, in part, to the modulation of pro-inflammatory enzyme activities. 相似文献
60.
Tahira Foyzun Abdullah Al Mahmud Md. Salim Ahammed Md. Imran Nur Manik Md. Kamrul Hasan KM Monirul Islam Simin Sobnom Lopa Md. Yusuf Al-Amin Kushal Biswas Mst. Rejina Afrin AHM Khurshid Alam Golam Sadik 《Molecules (Basel, Switzerland)》2022,27(3)
Neurotoxicity is a serious health problem of patients chronically exposed to arsenic. There is no specific treatment of this problem. Oxidative stress has been implicated in the pathological process of neurotoxicity. Polyphenolics have proven antioxidant activity, thereby offering protection against oxidative stress. In this study, we have isolated the polyphenolics from Acacia nilotica and investigated its effect against arsenic-induced neurotoxicity and oxidative stress in mice. Acacia nilotica polyphenolics prepared from column chromatography of the crude methanol extract using diaion resin contained a phenolic content of 452.185 ± 7.879 mg gallic acid equivalent/gm of sample and flavonoid content of 200.075 ± 0.755 mg catechin equivalent/gm of sample. The polyphenolics exhibited potent antioxidant activity with respect to free radical scavenging ability, total antioxidant activity and inhibition of lipid peroxidation. Administration of arsenic in mice showed a reduction of acetylcholinesterase activity in the brain which was counteracted by Acacia nilotica polyphenolics. Similarly, elevation of lipid peroxidation and depletion of glutathione in the brain of mice was effectively restored to normal level by Acacia nilotica polyphenolics. Gallic acid methyl ester, catechin and catechin-7-gallate were identified in the polyphenolics as the major active compounds. These results suggest that Acacia nilotica polyphenolics due to its strong antioxidant potential might be effective in the management of arsenic induced neurotoxicity. 相似文献