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Mixed convection peristaltic flow of Jeffrey nanofluid in a channel with compliant walls is addressed here. The present investigation includes the viscous dissipation, thermal radiation and Joule heating. Whole analysis is performed for velocity, thermal and concentration slip conditions. Related problems through long wavelength and low Reynolds number are examined for stream function, temperature and concentration. Impacts of thermal radiation, Hartman number, Brownian motion parameter, thermophoresis, Joule heating and slip parameters are explored in detail. Clearly temperature is a decreasing function of Hartman number and radiation parameter. 相似文献
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The adsorption and immobilisation of human insulin onto the bio-compatible nanosheets including graphene monoxide, silicon carbide and boron nitride nanosheets were studied by molecular dynamics simulation at the temperature of 310 K. After equilibration, heating and 100 ns production molecular dynamic runs, it was found that the insulin was adsorbed and immobilised onto the considered surfaces in a native folded state. The structural parameters, including root-mean-square deviation and fluctuation, surface accessible solvent area, radius of gyration (Rg) and the distance between the centre of the mass of immobilised protein and the surface of the considered nanosheets, were measured, analysed and discussed. The energetics of the studied systems such as the interaction energy between protein and nanosheet was also measured and addressed. The discussions were centred on the structural and energetic parameters of the protein and nanosheets, including charge density, hydrophobicity, hydrophilicity and residue polarity. The results also showed that the active site of C-termini of chain B played an important role in the adsorption process and this could be helpful in the protection of insulin in its smart delivery and release applications. 相似文献
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Abstract: 5-Hydroxytryptamine3 (5-HT3 ) receptors are the only known monoamine receptors mediating fast excitatory responses in mammalian neurons. Their primary structure as well as their electrophysiological and pharmacological properties show a phylogenetic relation to nicotinic acetylcholine, GABAA , and glycine receptors. As a prototypical member of this gene superfamily, we investigated the membrane topology of functional homomeric 5-HT3 receptors by using epitope tagging of the channel subunits expressed in heterologous systems. Visualization of 5-HT3 receptors in transfected COS-7 cells, either in western blot (molecular mass 61.2 ± 0.8 kDa) or in situ, was performed with previously characterized antibodies recognizing artificial epitopes as well as with anti-fusion protein antibodies directed against a wild-type receptor intracellular domain. The extracellular location of the distal C-terminal tagged domain demonstrates the presence of a fourth transmembrane domain in 5-HT3 serotonin-gated channels. In this region, the significant homology between members of this class of neurotransmitter-gated channels suggests strongly that they have a common transmembrane organization basically different from glutamate-gated and ATP-gated channels. 相似文献
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Seyede Saba Hosseini Seyed Omar Ebrahimi Maryam Haji Ghasem Kashani Somayeh Reiisi 《Cell biology international》2023,47(1):98-109
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities. 相似文献
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Martine de Boer Maaike te Lintel Hekkert Jiang Chang Bibi S. van Thiel Leonie Martens Maxime M. Bos Marion G. J. de Kleijnen Yanto Ridwan Yanti Octavia Elza D. van Deel Lau A. Blonden Renata M. C. Brandt Sander Barnhoorn Paula K. Bautista-Niño Ilona Krabbendam-Peters Rianne Wolswinkel Banafsheh Arshi Mohsen Ghanbari Christian Kupatt Leon J. de Windt A. H. Jan Danser Ingrid van der Pluijm Carol Ann Remme Monika Stoll Joris Pothof Anton J. M. Roks Maryam Kavousi Jeroen Essers Jolanda van der Velden Jan H. J. Hoeijmakers Dirk J. Duncker 《Aging cell》2023,22(3):e13768
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Ulviye Acar Çevik Ismail Celik Ufuk İnce Zahra Maryam Iqrar Ahmad Harun Patel Yusuf Özkay Zafer Asım Kaplancıklı 《化学与生物多样性》2023,20(3):e202201146
In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f . 相似文献
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Aysan Etemadi Salar Hemmati Mohammad Shahrivar-Gargari Yasaman Tamaddon Abibiglue Ahad Bavili Maryam Hamzeh-Mivehroud Siavoush Dastmalchi 《化学与生物多样性》2023,20(8):e202300075
Indanone derivatives containing meta/para-substituted aminopropoxy benzyl/benzylidene moieties were designed based on the structures of donepezil and ebselen analogs as the cholinesterase inhibitors. The designed compounds were synthesized and their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were measured. Inhibitory potencies (IC50 values) for the synthesized compounds ranged from 0.12 to 11.92 μM and 0.04 to 24.36 μM against AChE and BChE, respectively. Compound 5 c showed the highest AChE inhibitory potency with IC50 value of 0.12 μM, whereas the highest BChE inhibition was achieved by structure 7 b (IC50=0.04 μM). Structure-activity relationship (SAR) analysis revealed that there is no significant difference between meta and para-substituted derivatives in AChE and BChE inhibition. However, the most potent AChE inhibitor 5 c belongs to meta-substituted compounds, while the most active BChE inhibitor is para-substituted derivative 7 b . The order of enzyme inhibition potency based on the substituted amine group is dimethyl amine>piperidine>morpholine. Compounds containing C=C linkage are more potent AChE inhibitors than the corresponding saturated structures. Molecular docking studies indicated that 5 c interacts with AChE in a very similar way to that observed experimentally for donepezil. The introduced indanone-aminopropoxy benzylidenes could be used in drug-discovery against Alzheimer's disease. 相似文献