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1.
Lili Chen Nanami Fujisawa Masato Takanohashi Mazaya Najmina Koichiro Uto Mitsuhiro Ebara 《International journal of molecular sciences》2021,22(5)
This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery. 相似文献
2.
Dr. Daniel Feder Dr. Siti H. Mohd-Pahmi Dr. Waleed M. Hussein Prof. Luke W. Guddat Prof. Ross P. McGeary Prof. Gerhard Schenk 《ChemMedChem》2021,16(21):3342-3359
Metallohydrolases form a large group of enzymes that have fundamental importance in a broad range of biological functions. Among them, the purple acid phosphatases (PAPs) have gained attention due to their crucial role in the acquisition and use of phosphate by plants and also as a promising target for novel treatments of bone-related disorders and cancer. To date, no crystal structure of a mammalian PAP with drug-like molecules bound near the active site is available. Herein, we used a fragment-based design approach using structures of a mammalian PAP in complex with the MaybridgeTM fragment CC063346, the amino acid L-glutamine and the buffer molecule HEPES, as well as various solvent molecules to guide the design of highly potent and efficient mammalian PAP inhibitors. These inhibitors have improved aqueous solubility when compared to the clinically most promising PAP inhibitors available to date. Furthermore, drug-like fragments bound in newly discovered binding sites mapped out additional scaffolds for further inhibitor discovery, as well as scaffolds for the design of inhibitors with novel modes of action. 相似文献
3.
以“创新、协调、绿色、开放、共享”为内核的新发展理念,是对马克思主义发展理念的继承和发扬,极具时代精神,富含问题意识,为高校思想政治教育发展、教育教学改革实践提供了强大的理论支撑。本文以“通信原理”为例,阐述了新发展理念在课程改革中的思路和方法,实现了思想政治教育与专业基础课程有机融合,为深化高校教学改革、创新人才培养模式提供了思路。 相似文献
4.
Marta Baranowska-Kuczko Hanna Kozowska Monika Kloza Ewa Harasim-Symbor Micha Biernacki Irena Kasacka Barbara Malinowska 《International journal of molecular sciences》2021,22(9)
Our study aimed to examine the effects of hypertension and the chronic administration of the fatty acid amide hydrolase (FAAH) inhibitor URB597 on vascular function and the endocannabinoid system in spontaneously hypertensive rats (SHR). Functional studies were performed on small mesenteric G3 arteries (sMA) and aortas isolated from SHR and normotensive Wistar Kyoto rats (WKY) treated with URB597 (1 mg/kg; twice daily for 14 days). In the aortas and sMA of SHR, endocannabinoid levels and cannabinoid CB1 receptor (CB1R) expression were elevated. The CB1R antagonist AM251 diminished the methanandamide-evoked relaxation only in the sMA of SHR and enhanced the vasoconstriction induced by phenylephrine and the thromboxane analog U46619 in sMA in SHR and WKY. In the sMA of SHR, URB597 elevated anandamide levels, improved the endothelium-dependent vasorelaxation to acetylcholine, and in the presence of AM251 reduced the vasoconstriction to phenylephrine and enhanced the vasodilatation to methanandamide, and tended to reduce hypertrophy. In the aortas, URB597 elevated endocannabinoid levels improved the endothelium-dependent vasorelaxation to acetylcholine and decreased CB1R expression. Our study showed that hypertension and chronic administration of URB597 caused local, resistance artery-specific beneficial alterations in the vascular endocannabinoid system, which may bring further advantages for therapeutic application of pharmacological inhibition of FAAH. 相似文献
5.
6.
In this work, gallium doped copper sulfide (Ga-doped CuS) nanocrystals were prepared using a solvothermal method. The effects of Ga doping on the crystal structures, chemical composition, morphology, optical properties and thermal performance of copper sulfide (CuS) were investigated. The Ga-doped CuS nanocrystals had a hexagonal structure comparable to that of pure CuS. The Cu+/Cu2+ ratio first decreased and then increased with increasing Ga3+ doping. Both CuS and Ga-doped CuS exhibited nanoplate and nanorod morphologies. The visible transmittance of the Ga-doped CuS films was in the range of 61–77.1%. Importantly, the near-infrared (NIR) shielding performance of the films can be tuned by adjusting the concentration of the Ga dopant. The NIR shielding value of the optimal Ga-doped CuS film was 72.4%, which was approximately 1.5 times as high as that of the pure CuS film. This can be ascribed to the enhanced plasmonic NIR absorption that resulted from an increase in the hole concentration after doping with Ga3+ ions. In the thermal performance test, the Ga-doped CuS film lowered the interior temperature of the heat box by 9.1 °C. Therefore, the integration of good visible transmittance and high NIR shielding performance make the Ga-doped CuS nanocrystals a promising candidate for energy-efficient window coatings. 相似文献
7.
Keshun Liu 《Journal of the American Oil Chemists' Society》2019,96(6):635-645
For measuring trypsin inhibitor (TI) activities in soybean products, the current standard method, approved and reapproved by American Oil Chemists Society (Method Ba 12-75) and American Association of Cereal Chemists International (Method 22-40.01), features mixing trypsin with a series of inhibitor levels and then adding a substrate to start the colorimetric reaction. Yet, previous studies have shown flaws with the method, particularly with using several inhibitor levels and the sequence of adding the substrate last. The present study showed that with varying levels of dilution and volumes of a dilute sample extract, the pH of the premix (the mixture of a dilute sample extract and trypsin solution) ranged 3.30–3.60 for raw soy flour, and 3.20–6.70 for toasted soy. Within these premix pH ranges, the standard method of adding substrate last would give TI values equal to or less than those measured by the same method except for adding the enzyme last. The standard method was subsequently improved by using a single sample extract level and the enzyme-last sequence. Other modifications included making stock solutions for reagents, adding Ca2+ to the trypsin solution, diluting sample extracts to a level that causes 30–70% of inhibition, and running both reference and sample blanks for better controls. Alternatively, the full volume assay (10 mL total, as in the standard method) was further modified by using half the volume of each reagent with the same concentration. Compared to the standard method, the improved methods gave more consistent results when assaying 11 selected soy products. The half volume (5 mL) and full volume methods gave the same results, but the former could increase assay sensitivity and reduce amounts of reagents used. 相似文献
8.
9.
《Ceramics International》2022,48(3):3669-3675
ZnAl2O4 nanocrystalline particles were prepared using the solution combustion method using a new combustion fuel, Leucine. The prepared samples' structural, microstructural–elemental composition, and optical characteristics were investigated using XRD, SEM-EDS, and UV–Visible spectroscopy. As-synthesized ZnAl2O4 nanoparticles are polycrystalline, with no secondary phases, and crystallized in a cubic - spinel structure. The polycrystalline nature of the prepared sample is due to the exothermicity of fuel and oxidizer, which demonstrate that the fuel utilized (Leucine) provided adequate energy for the production of nanoparticles in their as-synthesized form, as supported by adiabatic temperature through thermodynamic calculations. The thermodynamic calculations also include a universal method to estimate the specific heat capacity at constant pressure. Furthermore, even after 2 h of calcination at 600 °C, ZnAl2O4 exhibits a single phase with no secondary phases, indicating the material stability and single-phase nature. The crystallinity of ZnAl2O4 nanoparticles was observed to increase with increasing annealing temperature. SEM micrographs of as-synthesized samples exhibit the formation of dense particles, voids, and pores in the as-synthesized sample. In addition, tiny aggregates were detected on the surface of more prominent clusters, which reduced as the calcination progressed. In addition, calcined samples exhibit a greater optical reflectance than as-synthesized samples. Tauc's graphs were used to compute the optical energy bandgap. The calculated energy band gap is redshifted to that of the bulk material. The bandgap energy decreases upon calcination, suggesting that the prepared materials have a larger crystallite size or more crystallinity. Correlations were found between the Tad, and the structural and optical properties of the prepared samples. The findings suggest that Leucine could be used as a novel combustion fuel to produce crystalline ZnAl2O4 nanoparticles in their as-synthesis form. 相似文献
10.