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21.
Masahiro Mikuriya Yuko Naka Ayumi Inaoka Mika Okayama Daisuke Yoshioka Hiroshi Sakiyama Makoto Handa Motohiro Tsuboi 《Molecules (Basel, Switzerland)》2022,27(13)
A mixed-valent trinuclear complex with 1,3-bis(5-chlorosalicylideneamino)-2-propanol (H3clsalpr) was synthesized, and the crystal structure was determined by the single-crystal X-ray diffraction method at 90 K. The molecule is a trinuclear CoIII-CoII-CoIII complex with octahedral geometries, having a tetradentate chelate of the Schiff-base ligand, bridging acetate, monodentate acetate coordination to each terminal Co3+ ion and four bridging phenoxido-oxygen of two Schiff-base ligands, and two bridging acetate-oxygen atoms for the central Co2+ ion. The electronic spectral feature is consistent with the mixed valent CoIII-CoII-CoIII. Variable-temperature magnetic susceptibility data could be analyzed by consideration of the axial distortion of the central Co2+ ion with the parameters Δ = –254 cm−1, λ = –58 cm−1, κ = 0.93, tip = 0.00436 cm3 mol−1, θ = –0.469 K, gz = 6.90, and gx = 2.64, in accordance with a large anisotropy. The cyclic voltammogram showed an irreversible reduction wave at approximately −1.2 V·vs. Fc/Fc+, assignable to the reduction of the terminal Co3+ ions. 相似文献
22.
Megan Douglass Sean Hopkins Rashmi Pandey Priya Singha Megan Norman Hitesh Handa 《Macromolecular bioscience》2021,21(1)
The novel use of nanofibers as a physical barrier between blood and medical devices has allowed for modifiable, innovative surface coatings on devices ordinarily plagued by thrombosis, delayed healing, and chronic infection. In this study, the nitric oxide (NO) donor S‐nitrosoglutathione (GSNO) is blended with the biodegradable polymers polyhydroxybutyrate (PHB) and polylactic acid (PLA) for the fabrication of hemocompatible, antibacterial nanofibers tailored for blood‐contacting applications. Stress/strain behavior of different concentrations of PHB and PLA is recorded to optimize the mechanical properties of the nanofibers. Nanofibers incorporated with different concentrations of GSNO (10, 15, 20 wt%) are evaluated based on their NO‐releasing kinetics. PLA/PHB + 20 wt% GSNO nanofibers display the greatest NO release over 72 h (0.4–1.5 × 10?10 mol mg?1 min?1). NO‐releasing fibers successfully reduce viable adhered bacterial counts by ≈80% after 24 h of exposure to Staphylococcus aureus. NO‐releasing nanofibers exposed to porcine plasma reduce platelet adhesion by 64.6% compared to control nanofibers. The nanofibers are found noncytotoxic (>95% viability) toward NIH/3T3 mouse fibroblasts, and 4′,6‐diamidino‐2‐phenylindole and phalloidin staining shows that fibroblasts cultured on NO‐releasing fibers have improved cellular adhesion and functionality. Therefore, these novel NO‐releasing nanofibers provide a safe antimicrobial and hemocompatible coating for blood‐contacting medical devices. 相似文献
23.
The surface pressure-molecular area curve of the mixed monolayer of 16-(9-anthroyloxy) palmitic acid (16AP) and fatty acid (palmitic or stearic acids) showed various kink points which indicated the phase transitions of the monolayer. On the basis of the surface phase rule, the phase diagrams of the mixed monolayer were elucidated. The bifunctional molecule, 16AP, takes two orientations in a monolayer state, that is, horizontal and vertical ones. Horizontally oriented 16AP and vertically oriented fatty acid form a mixed monolayer but this exhibits deviation from the ideal mixing, which was interpreted in terms of the surface regular solution theory. On the other hand, the 16AP molecule in the vertical state was found to be immiscible with the fatty acid molecule in a monolayer de spite both molecules being vertical to the surface and parallel to each other. This was caused by the participation of the 9-anthroyloxy moiety of 16AP in the interaction of 16AP and fatty acid in the hydrophobic region of the monolayer. 相似文献
24.
Vijayakumar Uppar Sandeep Chandrashekharappa Chandan Shivamallu Sushma P Shiva Prasad Kollur Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Atiyaparveen I. Basarikatti Mallikarjun Chougala Mrudula Mohan M Govindappa Banuprakash Jayadev Katharigatta N. Venugopala Belakatte P. Nandeshwarappa Ravindra Veerapur Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Kiran K. Mudnakudu-Nagaraju Basavaraj Padmashali Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2021,26(9)
25.
Naproxen Inhibits UVB‐induced Basal Cell and Squamous Cell Carcinoma Development in Ptch1+/−/SKH‐1 Hairless Mice 下载免费PDF全文
Sandeep C. Chaudhary Mohammad Waseem Mehtab Rana Hui Xu Levy Kopelovich Craig A. Elmets Mohammad Athar 《Photochemistry and photobiology》2017,93(4):1016-1024
Naproxen possesses anti‐proliferative and pro‐apoptotic effects besides its known anti‐inflammatory functions. Here, we demonstrate the anticancer effects of naproxen against UVB‐induced basal cell carcinoma (BCCs) and squamous cell carcinoma (SCCs) in a highly susceptible murine model of UVB carcinogenesis. Naproxen significantly inhibited UVB‐induced BCCs and SCCs in this model. Tumor number and volume were significantly decreased (P < 0.005 and P < 0.05, respectively). Inhibition in UVB‐induced SCCs and BCCs was 77% and 86%, respectively, which was associated with reduced PCNA and cyclin D1 and increased apoptosis. As expected, inflammation‐related iNOS, COX‐2 and nuclear NFκBp65 were also diminished by naproxen treatment. Residual tumors excised from naproxen‐treated animal were less invasive and showed reduced expression of epithelial‐mesenchymal transition (EMT) markers N‐cadherin, Vimentin, Snail and Twist with increased expression of E‐cadherin. In BCC and SCC cells, naproxen‐induced apoptosis and activated unfolded protein response (UPR) signaling with increased expression of ATF4, p‐eIF2α and CHOP. Employing iRNA‐based approaches, we found that naproxen‐induced apoptosis was regulated by CHOP as sensitivity of these cutaneous neoplastic cells for apoptosis was significantly diminished by ablating CHOP. In summary, these data show that naproxen is a potent inhibitor of UVB‐induced skin carcinogenesis. ER stress pathway protein CHOP may play an important role in inducing apoptosis in cancer cells. 相似文献
26.
Sandeep Kumar Maurya Dheerendra Yadav Debabrata Goswami 《Journal of fluorescence》2016,26(5):1573-1577
We investigate the effect of cetyl-trimethyl-ammonium-bromides (CTAB) concentration on the fluorescence of Rhodamine-6G in water. This spectroscopic study of Rhodamine-6G in presence of CTAB was performed using two-photon-induced-fluorescence at 780 nm wavelength using high repetition rate femtosecond laser pulses. We report an increment of ~10 % in the fluorescence in accordance with ~12 % enhancement in the absorption intensity of the dye molecule around the critical micellar concentration. We discuss the possible mechanism for the enhancement in the two-photon fluorescence intensity and the importance of critical micellar concentration. 相似文献
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29.
Sandeep Suryabhan Gholap Dr. Masanori Takimoto Prof. Dr. Zhaomin Hou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8547-8552
The alkylative carboxylation of allenamide catalyzed by an N‐heterocyclic carbene (NHC)–copper(I) complex [(IPr)CuCl] with CO2 and dialkylzinc reagents was investigated. The reaction of allenamides with dialkylzinc reagents (1.5 equiv) and CO2 (1 atm.) proceeded smoothly in the presence of a catalytic quantity of [(IPr)CuCl] to afford (Z)‐α,β‐dehydro‐β‐amino acid esters in good yields. The reaction is regioselective, with the alkyl group introduced onto the less hindered γ‐carbon, and the carboxyl group introduced onto the β‐carbon atom of the allenamides. The first step of the reaction was alkylative zincation of the allenamides to give an alkenylzinc intermediate followed by nucleophilic addition to CO2. A variety of cyclic and acyclic allenamides were found to be applicable to this transformation. Dialkylzinc reagents bearing β‐hydrogen atoms, such as Et2Zn or Bu2Zn, also gave the corresponding alkylative carboxylation products without β‐hydride elimination. The present methodology provides an easy route to alkyl‐substituted α,β‐dehydro‐β‐amino acid ester derivatives under mild reaction conditions with high regio‐ and stereoselectivtiy. 相似文献
30.