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61.
Ankita Mitra Akash Ahuja Laily Rahmawati Han Gyung Kim Byoung Young Woo Yong Deog Hong Mohammad Amjad Hossain Zhiyun Zhang Soo-Yong Kim Jongsung Lee Jong-Hoon Kim Jae Youl Cho 《Molecules (Basel, Switzerland)》2021,26(21)
Caragana rosea Turcz, which belongs to the Leguminosae family, is a small shrub found in Northern and Eastern China that is known to possess anti-inflammatory properties and is used to treat fever, asthma, and cough. However, the underlying molecular mechanisms of its anti-inflammatory effects are unknown. Therefore, we used lipopolysaccharide (LPS) in RAW264.7 macrophages to investigate the molecular mechanisms that underlie the anti-inflammatory activities of a methanol extract of Caragana rosea (Cr-ME). We showed that Cr-ME reduced the production of nitric oxide (NO) and mRNA levels of iNOS, TNF-α, and IL-6 in a concentration-dependent manner. We also found that Cr-ME blocked MyD88- and TBK1-induced NF-κB and IRF3 promoter activity, suggesting that it affects multiple targets. Moreover, Cr-ME reduced the phosphorylation levels of IκBα, IKKα/β and IRF3 in a time-dependent manner and regulated the upstream NF-κB proteins Syk and Src, and the IRF3 protein TBK1. Upon overexpression of Src and TBK1, Cr-ME stimulation attenuated the phosphorylation of the NF-κB subunits p50 and p65 and IRF3 signaling. Together, our results suggest that the anti-inflammatory activity of Cr-ME occurs by inhibiting the NF-κB and IRF3 signaling pathways. 相似文献
62.
Ravi Patel Abhishek Dube Ravisinh Solanki Dignesh Khunt Shalin Parikh Vijayabhaskarreddy Junnuthula Sathish Dyawanapelly 《Molecules (Basel, Switzerland)》2022,27(17)
A novel stability-indicating, reversed-phase, high-performance liquid chromatography (RP-HPLC) method was developed and validated for the determination of favipiravir in an oral suspension. The effective separation of favipiravir and its degradation products was achieved on a Zorbax Eclipse Plus C18 column (5 μm particle size, 150 mm length × 4.6 mm diameter). The mobile phase was prepared by mixing 5 mM of phosphate buffer (pH 3.5) and methanol in a 75:25 v/v ratio delivered at a 1.0 mL/min flow rate. The eluents were monitored using a photodiode array detector at a wavelength of 322 nm. The stability-indicating nature of this method was evaluated by performing force degradation studies under various stress conditions, such as acidic, alkali, oxidative, thermal, and photolytic degradation. Significant degradation was observed during the alkali stress degradation condition. The degradation products generated during various stress conditions were well separated from the favipiravir peak. In addition, the major degradation product formed under alkali stress conditions was identified using UPLC-ESI-TQ-MS/MS and NMR. Method validation was performed according to the ICH Q2 (R1) guideline requirements. The developed method is simple, accurate, robust, and reliable for routine quality control analysis of favipiravir oral suspensions. 相似文献
63.
Epunctanone,a New Benzophenone,and Further Secondary Metabolites from Garcinia epunctata Stapf (Guttiferae) 下载免费PDF全文
Ghislain W. Fotso Aku N. Ntumy Eliette Ngachussi Mthandazo Dube Renameditswe Mapitse Gilbert D. W. F. Kapche Kerstin Andrae‐Marobela Bonaventure T. Ngadjui Berhanu M. Abegaz 《Helvetica chimica acta》2014,97(7):957-964
A new polyprenylated benzophenone, named epunctanone ( 1 ), was isolated from the stem bark of Garcinia epunctata Stapf , together with eight known compounds, 7‐epiisogarcinol ( 2 ), 2,6‐dimethoxy‐p‐benzoquinone ( 3 ), friedelin ( 4 ), lupeol ( 5 ), 16β‐hydroxylupeol ( 6 ), betulin ( 7 ), stigmasterol ( 8 ), and rheediaxanthone A ( 9 ). The structure of epunctanone ( 1 ) was established by detailed analysis of its spectroscopic data, especially 1D‐ and 2D‐NMR, and HR‐MS data. All these compounds were evaluated for their antimicrobial and anti‐protozoan activities. They were also assayed to determine if any of the compounds were nonpeptide agonist ligands for nematodal G‐protein‐coupled receptors, which would be an indication of potential antinematodal activity. Among the isolated compounds, 7‐epiisogarcinol ( 2 ) was the most active against Candida albicans. 相似文献
64.
Summary The dual separation mechanism exhibited by capillary electrochromatography is demonstrated by the simultaneous separation
of sulfonamides as charged and neutral species over a pH range of 2.5 to 6.9. The neutral sulfonamides were separated according
to the difference in their hydrophobicities while charged components were separated by the differences in their electrophoretic
mobilities. The limitation of capillary electrochromatography for acidic components was also examined. 相似文献
65.
Manuel Guentner Edgar Uhl Dr. Peter Mayer Dr. Henry Dube 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16433-16436
The first example of a bis‐hemithioindigo (bis‐HTI)‐based molecular receptor was realized. Its folding and selective binding affinity for aromatic guest molecules can be precisely controlled by visible light and heat. The thermodynamically stable state of the bis‐HTI is the s‐shaped planar Z,Z‐configuration. After irradiation with 420 nm light only the E,Z‐configuration is formed in a highly selective photoisomerization. The E,Z‐isomer adopts a helical conformation because of the implementation of repulsive steric interactions. The E,Z‐configured helix is able to recognize electron‐poor aromatic guests exclusively through polar aromatic interactions and also distinguishes between regioisomers. After heating, the Z,Z‐configuration is completely restored and the aromatic guest molecule is efficiently released. 相似文献
66.
Sonandkar Abhijeet A. Agrawal Pradeep N. Madrewar Dnyanoba M. Labana Sneha M. Jain Ankita P. 《平面色谱法杂志一现代薄层色谱法》2014,27(5):357-361
JPC – Journal of Planar Chromatography – Modern TLC - Impatiens balsamina belonging to family Balsaminaceae is commonly known as terda. The plant has extensive range of... 相似文献
67.
Davlat Kh. Akramov Nilufar Z. Mamadalieva Andrea Porzel Hidayat Hussain Mthandazo Dube Akbar Akhmedov Ahmed E. Altyar Mohamed L. Ashour Ludger A. Wessjohann 《Molecules (Basel, Switzerland)》2021,26(6)
Phytochemical investigation of the methanolic extract obtained from the aerial parts of Lagochilus setulosus (Lamiaceae) afforded the new compound 1-methoxy-3-O-β-glucopyranosyl-α-l-oliose (1) together with five known glycosides, namely sitosterol-3-O-β-glucoside (2), stigmasterol-3-O-β-glucoside (3), pinitol (4), 6β-hydroxyl-7-epi-loganin (5), and chlorotuberoside (6). The structures of these compounds were elucidated by extensive spectroscopic analyses, especially HR-MS, 1D and 2D NMR spectroscopy. The in vitro cytotoxic activity of the methanolic extract and the isolated compounds was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and crystal violet (CV) staining assays. In addition, the antifungal activities of the components were evaluated against Botrytis cinerea, Septoria tritici, and Phytophthora infestans. The anthelmintic potential was determined against Caenorhabditis elegans nematodes. Neither the extract nor the isolated compounds showed promising activity in all the bioassays. 相似文献
68.
69.
Tripathy Debajani Chakroborty Subhendu Gadtya Ankita Subhrasmita Mahaling Ram Naresh Moharana Srikanta Barik Arundhati Pal Kaushik 《The European physical journal. E, Soft matter》2023,46(3):1-13
The European Physical Journal E - We discuss the lateral dynamics of two active force dipoles, which interact with each other via hydrodynamic interactions in a thin fluid layer that is active and... 相似文献
70.
Themba Dube 《Algebra Universalis》2013,70(2):197-212
We consider some frame-theoretic properties of the hull-kernel and the inverse topologies on the set of minimal prime ideals of an algebraic frame with the finite intersection property on its compact elements. Denote by Alg do the subcategory of Frm consisting of such frames together with dense onto coherent maps. We construct a functor ${{\sf T} : {\bf Alg}_{\rm do} \rightarrow {\bf Frm}}$ T : Alg do → Frm and a natural transformation ${\tau : {\sf E} \rightarrow {\sf T}}$ τ : E → T , where E is the inclusion functor from Alg do to Frm. 相似文献