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101.
102.
Haya Hussain Shujaat Ahmad Syed Wadood Ali Shah Abid Ullah Niaz Ali Mazen Almehmadi Manzoor Ahmad Atif Ali Khan Khalil Syed Babar Jamal Hanif Ahmad Mustafa Halawi 《Molecules (Basel, Switzerland)》2022,27(8)
Alzheimer’s disease is an emerging health disorder associated with cognitive decline and memory loss. In this study, six curcumin analogs (1a–1f) were synthesized and screened for in vitro cholinesterase inhibitory potential. On the basis of promising results, they were further investigated for in vivo analysis using elevated plus maze (EPM), Y-maze, and novel object recognition (NOR) behavioral models. The binding mode of the synthesized compounds with the active sites of cholinesterases, and the involvement of the cholinergic system in brain hippocampus was determined. The synthesized curcumin analog 1d (p < 0.001, n = 6), and 1c (p < 0.01, n = 6) showed promising results by decreasing retention time in EPM, significantly increasing % SAP in Y-maze, while significantly (p < 0.001) enhancing the % discrimination index (DI) and the time exploring the novel objects in NORT mice behavioral models. A molecular docking study using MOE software was used for validation of the inhibition of cholinesterase(s). It has been indicated from the current research work that the synthesized curcumin analogs enhanced memory functions in mice models and could be used as valuable therapeutic molecules against neurodegenerative disorders. To determine their exact mechanism of action, further studies are suggested. 相似文献
103.
Mansur B. Ibrahim Imran Malik S. M. Shakil Hussain Atif Fazal Mohammed Fettouhi Bassam El Ali 《Transition Metal Chemistry》2016,41(7):739-749
Palladium–bis(oxazoline) complexes (Pd-BOX-A and Pd-BOX-B) were synthesized and characterized by 1H, 13C NMR, IR and elemental analysis. The molecular structures of the complexes were confirmed by single-crystal X-ray analysis. In both cases, the palladium center is coordinated by the nitrogen atoms of the two oxazoline rings and two chloride ligands in a distorted square planar geometry. Despite the fact that the bis(oxazoline) ligand is achiral, the asymmetrical substitution on the phenyl spacer and the rigid backbone of the complex Pd-BOX-A induce inherent chirality and the compound crystallizes as a racemic mixture. Both complexes were found to be highly effective catalysts for Suzuki–Miyaura, Mizoroki–Heck and Sonogashira cross-coupling reactions. They also show excellent catalytic activities toward carbonylative coupling reactions. 相似文献
104.
Muhammad Tariq Saeed Chani Abdullah M. Asiri Kh. S. Karimov Atif Khan Niaz Sher Bhadar Khan Khalid. A. Alamry 《中国物理 B》2013,(11):629-633
This study presents the fabrication and temperature sensing properties of sensors based on aluminium phthalocyanine chloride(AlPcCl)thin films.To fabricate the sensors,50-nm-thick electrodes with 50-μm gaps between them are deposited on glass substrates.AlPcCl thin films with thickness of 50–100 nm are deposited in the gap between electrodes by thermal evaporation.The resistance of the sensors decreases with increasing thickness and the annealing at 100℃ results in an increase in the initial resistance of sensors up to 24%.The sensing mechanism is based on the change in resistance with temperature.For temperature varying from 25℃ to 80℃,the change in resistance is up to 60%.Simulation is carried out and results obtained coincide with experimental data with an error of±1%. 相似文献
105.
Atif F. Khan Ravishanker Yadav P. K. Mukhopadhya Sukhvir Singh Charu Dwivedi Viresh Dutta Santa Chawla 《Journal of nanoparticle research》2011,13(12):6837-6846
A distinct enhancement of upconversion luminescence from core to core/shell (C/S) structure under low flux near infrared (NIR)
excitation at 976 nm has been achieved in lanthanide (Er3+, Yb3+)-doped NaYF4 core with undoped NaYF4 shell nanoparticles (NP). A green chemistry approach has been taken to synthesize monodisperse monophasic C/S NP with the
core (~20 nm) and shell (~5 nm) crystallizing into cubic phase. Hydrophobic C/S NP have been further made hydrophilic by coating
a transparent SHMP layer without affecting luminescence. C/S (NaYF4: Er, Yb/NaYF4) NP integrated dye-sensitized solar cell indicated 11.9% enhancement in overall conversion efficiency under AM 1.5 conditions,
due to NIR–visible spectrum modification by fluorescent NPs. The results indicate great potential of such upconverting C/S
nanophosphor in solar cell applications. 相似文献
106.
107.
The aim of the current study is to simulate the laser photon through biological tissue during PDT therapy using Monte Carlo
simulation technique. The model is coded using MATLAB. Interaction of laser light with turbid medium e.g. human tissue depends
on the optical properties of the medium i.e. refractive index n, absorption coefficient μ
a
, scattering coefficient μ
s
and anisotropy factor g. Laser light transport through tissue is governed by the radiative transport equations based on absorption and scattering.
Direct sampling is used for step-size generation before interaction via absorption or scattering with the transmitting medium,
for deflection and azimuthal angle (θ and ϕ) when the scattering even occurs. The tissue medium considered is divided into
radial, axial and angular grid elements and an infinite narrow beam with normal incidence on the tissue is considered. The
laser light absorbance inside the tissue, reflectance at the top boundary of the tissue and transmittance at the bottom are
estimated and these quantities are shown varying radially and angularly. Results of reflectance, transmittance and fluence
are compared with the already published results to confirm the authenticity of our coding and these results are found to lie
at only 3–4% error. 相似文献
108.
The mechanism of inhibition of jack bean and Bacillus pasteurii ureases was investigated by triacontanyl palmitate (1) which is a long-chain fatty ester and has been isolated from Symplocos racemosa Roxb. Lineweaver-Burk, Dixon plots, and their secondary replots showed that 1 is a non-competitive inhibitor of these enzymes. K(i) values were found to be 60.03 +/- 1.72 and 88.23 +/- 0.31 microM against jack bean and B. pasteurii ureases, respectively. 相似文献
109.
110.
Hussain Atif Xun Gao Asghar Haroon Azam Muhammad Ain Qura-tul- Nawaz Zeesha 《Optics and Spectroscopy》2021,129(4):452-459
Optics and Spectroscopy - In this work, a comparative study for the laser-induced breakdown spectroscopy (LIBS) of aluminium (Al) target has been performed by using the two kinds of enhancement... 相似文献