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81.
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
82.
Vinay K. Singh Rahul Dubey Abhishek Upadhyay Laxmi Kant Sharma Rana Krishna Pal Singh 《Tetrahedron letters》2017,58(45):4227-4231
An efficient and economical method was developed for synthesis of 3-substituted indole by using electrochemically induced condensation of various aldehyde, indole and malononitrile. 相似文献
83.
Zafar A. Siddiqi M. Shahid Mohd Khalid Shabana Noor Sarvendra Kumar 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):61-68
The newly prepared homo-bimetallic complexes [M2(imda)2(H2O)4], [M2(imda)2(Bipy)2] (M = Co, Ni or Cu) and [Fe2(imda)2(H2O)3Cl] (H2imda = iminodiacetic acid and Bipy = 2,2′-bipyridine) have been studied employing IR, FAB-mass, 1H and 13C NMR, EPR and ligand field spectra, which indicated a high-spin state of metal ion with hexa-coordinate environment. 57Fe Mössbauer data of the homo-bimetallic complex [Fe2(imda)2(H2O)3Cl] confirm a high-spin configuration with Fe (±3/2 → 1/2) nuclear transitions and the presence of Kramer's double degeneracy. At RT, the spin–spin interactions of the neighbouring nuclei (Fe3+–Fe3+ = S5/2–S5/2) are anti-ferromagnetically coupled. However, at LNT, the complex acquires a mixed-valent [FeIII–FeII] composition corroborated from the X-band EPR data. CV studies indicated the presence of quasi-reversible redox CuII/I, CuII/III, FeIII/II, FeIII/I and FeII/I couples. 相似文献
84.
Zafar A. Siddiqi Mohd Khalid Sarvendra Kumar M. Shahid Shabana Noor 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):841-845
Spectral and molecular model computations on homo-dinuclear complexes [M2L2(H2O)2Cl2] [L = 1-(salicylaldeneamino)-3-hydroxypropane, M = Cr3+, Mn3+, Fe3+, Co3+, Ni3+ or Cu3+] are consistent with a distorted hexa-coordinate geometry. X-band EPR spectral data indicated a rhombic distortion around Cu(II) ion. Magnetic moment and 57Fe Mössbauer data confirmed a high-spin state electronic configuration (t2g3eg2, S = 5/2) and asymmetric ligand environment around Fe(III) with nuclear transitions Fe(±3/2 → 1/2) exhibiting Kramer's double degeneracy. The neighboring Fe(III) nuclei in the homo-dinuclear species are antiferromagnetically coupled. 相似文献
85.
B. K. Rana R. M. Tripathi S. K. Sahoo N. K. Sethy V. S. Sribastav A. K. Shukla V. D. Puranik 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(3):711-717
A brief study on dissolved radionuclides in aquatic environment, especially in ground water, constitutes the key aspect for assessment and control of natural exposure. In the present study the distribution of natural uranium and 226Ra concentration were measured in ground water samples collected within a 10 km radius around the Narwapahar uranium mine in the Singhbhum thrust belt of Jharkhand, India in 2007–2008. The natural uranium content in the ground water samples in this region was found to vary from 0.1 to 3.75 μg L?1 with an average of 0.87 ± 0.73 μg L?1 and 226Ra concentration was found to vary from 5.2 to 38.1 mBq L?1 with an average of 13.73 ± 7.34 mBq L?1. The mean annual ingestion dose due to intake of natural uranium and 226Ra through drinking water pathway to male and female adults population was estimated to be 6.55 and 4.78 μSv y?1, respectively, which constitutes merely a small fraction of the reference dose level of 100 μSv y?1 as recommended by WHO. 相似文献
86.
The title compound, a novel Ag(Ⅰ) carboxyarylphosphonate [Ag(H2BCP)(4,4'- bipy)]·2H2O (H3BCP = p-H2O3PCH2C6H4COOH, 4,4'-bipy = 4,4'-bipyridine), was synthesized by a hydrothermal reaction and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. It belongs to monoclinic system, space group P21/c with a = 5.7038(11), b = 22.397(4), c = 5.602(4) ?, β = 106.26(3)°, V = 1913.4(7) 3, Z = 4, C18H20N2O7PAg, Mr = 515.20, Dc = 1.788 g/cm3, μ = 1.182 mm-1, F(000) = 1040, the final R = 0.0404 and wR = 0.1216 for 4178 observed reflections with I 2σ(Ⅰ). In the structure, the Ag(Ⅰ) cations are bridged by 4,4'-bipy to give rise to 1D chains running along the b axis. These chains are linked further by the interactions of O (from BCP ligands) and Ag atoms to yield 2D layers. Hydrogen bonding interactions and weak π-π stacking interactions between 4,4'-bipy rings assemble such adjacent layers to generate a 3D supramolecular architecture. 相似文献
87.
Nosheen Akbar Bilal Masud Saba Noor 《The European Physical Journal A - Hadrons and Nuclei》2011,47(10):124
We propose some extensions of the quark potential model to hybrids, fit them to the lattice data and use them for the purpose of calculating the masses, root mean square radii and wave functions at the origin of the conventional and hybrid charmonium mesons. We treat the ground and excited gluonic field between a quark and an antiquark as in the Born-Oppenheimer expansion, and use the shooting method to numerically solve the required Schrödinger equation for the radial wave functions; from these wave functions we calculate the mesonic properties. For masses we also check through a Crank Nichelson discretization. For hybrid charmonium mesons, we consider the exotic quantum number states with J PC = 0+?, 1?+ and 2+?. We also compare our results with the experimentally observed masses and theoretically predicted results of the other models. Our results have implications for scalar form factors, energy shifts, magnetic polarizabilities, decay constants, decay widths and differential cross-sections of conventional and hybrid mesons. 相似文献
88.
The role of soft versus hard bistable systems on stochastic resonance using average cycle energy as a quantifier 总被引:1,自引:0,他引:1
S. Rana S. Lahiri A. M. Jayannavar 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,84(2):323-329
Using the input energy per cycle as a quantifier of stochastic resonance (SR), we show
that SR is observed in superharmonic (hard) potentials. However, it is not observed in
subharmonic (soft) potentials, even though the potential is bistable. These results are
consistent with recent observations based on amplitude of average position as a
quantifier. In both soft and hard potentials, we observe resonance phenomenon as a
function of the driving frequency. The nature of probability distributions of average work
are qualitatively different for soft and hard potentials. 相似文献
89.
90.
Muhammad Aslam Noor Muhammad Waseem Khalida Inayat Noor Eisa Al-Said 《Optimization Letters》2013,7(5):991-1007
In this paper, we use the variational iteration technique to suggest and analyze some new iterative methods for solving a system of nonlinear equations. We prove that the new method has fourth-order convergence. Several numerical examples are given to illustrate the efficiency and performance of the new iterative methods. Our results can be viewed as a refinement and improvement of the previously known results. 相似文献