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排序方式: 共有156条查询结果,搜索用时 31 毫秒
91.
Mariappan Rajan Rajendran Amarnath Praphakar Dharman Govindaraj Palanisamy Arulselvan S. Suresh Kumar 《Materials Today Chemistry》2017
The delivery of drugs in nanosized carriers arises as a very attractive solution. This study reports the in vitro cytotoxic effect of palbociclib loaded chitosan cross-linked polypropylene glycol nanocarriers. The nanocarriers were prepared by ion gelation using calcium chloride, calcium oxalate, and sodium tripolyphosphate as cross-linking agents. The influence of the cross-linking agent on the size and morphology of the chitosan- polypropylene glycol nanocarriers was studied by Dynamic Light Scattering (DLS), Scanning Electron Microscope (SEM), and Atomic Fluorescence Microscope (AFM). Tripolyphosphate assisted carriers was found higher amount palbociclib encapsulation capacity compared with other two carriers. The drug releasing behavior was studied at pH 6.8 which was based on the bulk erosion principal of the carriers. Palbociclib loaded chitosan-polypropylene glycol carriers were found to show excellent drug releasing kinetics and biocompatibility in in-vitro analysis. The unloaded chitosan-polypropylene glycol carrier was identified to have less inherent cytotoxicity, whereas the loaded carriers are as active as equal to pure palbociclib against the MCF-7 cancer cell line. The palbociclib loaded nanocarriers were studied to determine their potential anticancer activity against the MCF-7 cell line. The IC50 values of three carriers chitosan-polypropylene glycol -I, chitosan-polypropylene glycol -II and chitosan-polypropylene glycol -III was observed 55.4, 51.0 and 38.7 mg/μL respectively. The effect of palbociclib uptake was evaluated by confocal microscopy using acridine orange/ethidium bromide and 4, 6-diamidino-2-phenylindole staining. Palbociclib loaded chitosan-polypropylene glycol nanocarriers show promise as potential candidates for cancer therapeutic applications. 相似文献
92.
Thirumalaiandi Ramasubramanian Mariappan Paramasivam 《International journal of environmental analytical chemistry》2017,97(11):1037-1052
Fipronil has label claim for managing shoot borer and root borer of sugarcane. The dissipation and metabolism of fipronil in/on sugarcane crop have been studied under tropical field condition by employing a modified quick, easy, cheap, effective, rugged and safe sample preparation method and gas chromatography equipped with electron capture detector. The method could provide 90.27–98.97% recoveries of target analytes from cane leaves and stem with relative standard deviations of less than 5%. The sulphide, desulfinyl and sulfone metabolites of fipronil were detected along with the parent compound even in the 0-day samples of sugarcane leaves and stem collected 2 h post-foliar spraying. The total residues comprising fipronil and its three major metabolites got dissipated to 4.366 µg/g from the initial deposit of 12.977 µg/g within a day after foliar spray. Fipronil sulphide and fipronil desulfinyl were the major metabolites on sugarcane crop. The residues (both parent compound and total residues) reached below the detectable level of 0.005 µg/g on 7 and 15 days after treatment on stem and leaves, respectively. Half-life of fipronil was less than a day on sugarcane crop. The total residues had the half-life of 1.66 and 0.91 days on leaves and stem, respectively. 相似文献
93.
Pradeep Kumar Yadalam Thilagar Sivasankari Santhiya Rengaraj Maryam H. Mugri Mohammed Sayed Samar Saeed Khan Mona Awad Kamil Shilpa Bhandi A. Thirumal Raj Shankargouda Patil Artak Heboyan 《Molecules (Basel, Switzerland)》2022,27(9)
Simple SummaryIn spite of substantial investigation, the biological link between periodontitis and rheumatoid arthritis remains unexplained. This study intended to correlate periodontitis and rheumatoid arthritis gene expression patterns to find shared targets for both the disease. We identified the differentially expressed genes (DEGs) in periodontitis and rheumatoid arthritis. The network was built by integrating DEGs and ranking the genes using GeneMANIA. FINDSITEcomb2.0 was used to find a possible inhibitor for the top-ranked gene. Further, the binding effectiveness and protein-ligand complex stability were then determined by molecular docking and molecular dynamics. The network analysis showed IFI44L as a highly ranking gene implicated in most immunological pathways. A virtual screening of 6507 compounds revealed vemurafenib as the best candidate for the IFI44L target. Molecular docking and molecular dynamics modelling revealed the stability of the IFI44L-vemurafenib complex, which suggest IFI44L is potential target and vemurafenib could be the better candidate to treat both diseases.AbstractObjective: Despite extensive research on periodontitis and rheumatoid arthritis, the underlying molecular connectivity between these condition remains largely unknown. This research aimed to integrate periodontitis and rheumatoid arthritis gene expression profiles to identify interconnecting genes and focus to develop a common lead molecule against these inflammatory conditions. Materials and Methods: Differentially expressed genes (DEGs) of periodontitis and rheumatoid arthritis were identified from the datasets retrieved from the Gene Expression Omnibus database. The network was constructed by merging DEGs, and the interconnecting genes were identified and ranked using GeneMANIA. For the selected top ranked gene, the potential inhibitor was searched using FINDSITEcomb2.0. Subsequently, the molecular docking and molecular dynamics were performed to determine the binding efficiency and protein-ligand complex stability, respectively. Results: From the network analysis, IFN-induced protein 44-like (IFI44L) was identified as a top ranked gene involved in most of the immunological pathway. With further virtual screening of 6507 molecules, vemurafenib was identified to be the best fit against the IFI44L target. The binding energy and stability of IFI44L with vemurafenib were investigated using molecular docking and molecular dynamics simulation. Docking results show binding energy of −7.7 Kcal/mol, and the simulation results show stability till 100 ns. Conclusions: The identified IFI44L may represent a common drug target for periodontitis and rheumatoid arthritis. Vemurafenib could be a potent anti-inflammatory drug for both diseases. 相似文献
94.
Benzimidazolium perchlorate (BDP) a novel organic nonlinear optical material has been grown by slow evaporation technique. Growth parameters such as metastable zone width and induction period were determined. The relative second harmonic generation (SHG) efficiency of the material was investigated for the first time in the literature and was found to be 1.2 times higher than that of KDP. The grown crystals were subjected to X-ray diffraction, absorption spectrum, Fourier transform infrared (FT-IR) spectroscopy, thermal behavior, CHN analysis, and micro hardness studies. 相似文献
95.
G. Madhurambal B. Ravindran M. Mariappan K. Ramamurthi S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2011,104(3):875-878
A single crystal of cinnamic acid–urea was grown by slow evaporation of methanol solution at room temperature. In this research,
many analytical methods such as FTIR, second harmonic generation, NMR, and TG–DTA were used. The presence of title compound
in the crystal lattice has been qualitatively determined by FTIR analysis. Thermal stability of the grown crystals was evaluated
by TG-DTA. Incorporation of urea increases the thermal stability insuring the suitability of material for possible non-linear
optical application up to 180 °C. 相似文献
96.
Gilmore K Manoharan M Wu JI Schleyer Pv Alabugin IV 《Journal of the American Chemical Society》2012,134(25):10584-10594
The transition states (TSs) of 5-endo-dig and 5-endo-trig anionic ring closures are the first unambiguous examples of nonpericyclic reactions with TSs stabilized by aromaticity. Their five-center, six-electron in-plane aromaticity is revealed by the diatropic dissected nucleus-independent chemical shifts, -24.1 and -13.7 ppm, respectively, resulting from the delocalization of the lone pair at the nucleophilic center, a σ CC bond, and an in-plane alkyne (or alkene) π bond. Other seemingly analogous exo and endo cyclization TSs do not have these features. A symmetry-enhanced combination of through-space and through-bond interactions explains the anomalous geometric, energetic, and electronic features of the 5-endo ring closure transition state. Anionic 5-endo cyclizations can be considered to be "aborted" [2,3]-sigmatropic shifts. The connection between anionic cyclizations and sigmatropic shifts offers new possibilities for the design and electronic control of anionic isomerizations. 相似文献
97.
Chiral allenes are readily accessed in a single pot operation in the reaction of terminal alkynes, aldehydes, chiral secondary amines, and zinc halides in good yields (up to 77% yield) and excellent enantioselectivities (up to 99% ee) in toluene at 120 °C. The reaction proceeds through initial formation of chiral propargylamine intermediates with creation of a new stereogenic center and subsequent chirality transfer via an intramolecular hydride shift to produce chiral allenes with high enantiomeric purities. 相似文献
98.
Pure and tin doped zinc oxide (Sn:ZnO) thin films were prepared for the first time by NSP technique using aqueous solutions of zinc acetate dehydrate, tin (IV) chloride fendahydrate and methanol. X-ray diffraction patterns confirm that the films are polycrystalline in nature exhibiting hexagonal wurtzite type, with (0 0 2) as preferred orientation. The structural parameters such as lattice constant (‘a’ and ‘c’), crystallite size, dislocation density, micro strain, stress and texture coefficient were calculated from X-ray diffraction studies. Surface morphology was found to be modified with increasing Sn doping concentration. The ZnO films have high transmittance 85% in the visible region, and the transmittance is found to be decreased with the increase of Sn doping concentration. The corresponding optical band gap decreases from 3.25 to 3.08 eV. Room temperature photoluminescence reveals the sharp emission of strong UV peak at 400 nm (3.10 eV) and a strong sharp green luminescence at 528 nm (2.34 eV) in the Sn doped ZnO films. The electrical resistivity is found to be 106 Ω-cm at higher temperature and 105 Ω-cm at lower temperature. 相似文献
99.
Bučar DK Sen A Mariappan SV MacGillivray LR 《Chemical communications (Cambridge, England)》2012,48(12):1790-1792
A ditopic hydrogen-bond-donor template in the form of resorcinol facilitates a [2+2] cross-photodimerisation of 4-Cl-stilbazole and 4-Me-stilbazole in a rare cocrystal solid solution. A photoreaction does not proceed with the olefins individually or as a solid solution composed solely of the two olefins. 相似文献
100.
Alkyl substitution at the α position(s) of mono-, bi-, and terthiophenes via electrophilic addition of macrocyclic end caps combines linear, π-conjugated aromatic compounds and annular macrocycles. Addition of the Hg(II) ion to terthiophene adducts produces intense color changes, allowing for the selective, colorimetric detection of mercury(II). Chemical oxidation of the asymmetric terthiophene adduct produces the sexithiophene oligomer. 相似文献