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211.
212.
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
213.
Van Cantfort O. Abid A. Michaux B. Heinrichs B. Pirard R. Pirard J.P. Lecloux A.J. 《Journal of Sol-Gel Science and Technology》1997,8(1-3):125-130
Porous silica-alumina xerogels are synthesized through two methods, which differ by the aluminium precursor: aluminium tri-secbutoxide
and aluminium nitrate nonahydrate. The silicium precursor is tetraethylorthosilicate. The porous texture is studied by nitrogen
adsorption-desorption isotherms. It is found that the porous texture mainly depends on one parameter for each preparation
method: hydrolysis catalyst in one case and aluminium content in the other case. 相似文献
214.
S. Rahal P. Cerisier C. Abid 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,59(4):509-518
A study of dynamic regimes in Bénard-Marangoni convection
was carried out for various Prandtl and Marangoni numbers in small aspect
ratio geometries (Γ = 2.2 and 2.8). Experiments in a small hexagonal vessel, for a large range of the Marangoni number (from
148 to 3636), were carried out. Fourier
spectra and an auto-correlation function were used to recognize the various
dynamic regimes. For given values of the Prandtl number (Pr = 440) and aspect ratio
(Γ = 2.2), mono-periodic, bi-periodic and chaotic states were successively observed as the Marangoni number was increased.
The correlation dimensions of strange
attractors corresponding to the chaotic regimes were calculated. The
dimensions were found to be larger than those obtained by other authors for
Rayleigh-Bénard convection in aspect ratio geometries of the same order.
The transition from temporal chaos to spatio-temporal chaos was also
observed. For Γ = 2.2, when larger values of the Marangoni number were imposed (Ma = 1581 for Pr = 160 and Ma = 740 for Pr
= 440), spatial modes were involved through the convective pattern dynamics. 相似文献
215.
Muhammad Abid Saqib Jabbar Tao Wu Malik Muhammad Hashim Bing Hu Shicheng Lei Xin Zhang Xiaoxiong Zeng 《Ultrasonics sonochemistry》2013,20(5):1182-1187
Fresh apple juice treated with ultrasound (for 0, 30, 60 and 90 min, at 20 °C, 25 kHz frequency) was evaluated for different physico-chemical, Hunter color values, cloud value, antioxidant capacity, scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, ascorbic acid, total phenolics, flavonoids, flavonols and microbial characteristics. No significant effect of sonication was observed on pH, total soluble solids (°Brix) and titratable acidity of apple juice. Sonication significantly improved ascorbic acid, cloud value, phenolic compounds, antioxidant capacity, DPPH free radical scavenging activity and differences in Hunter color values. Moreover, significant reduction in microbial population was observed. Findings of the present study suggested that sonication treatment could improve the quality of apple juice. It may successfully be employed for the processing of apple juice with improved quality and safety from consumer’s health point of view. 相似文献
216.
In view of the differential phase Q (DP-Q) and the traditional Q factor, we compared, using numerical simulations, the performances of the RZ-OOK and RZ-DPSK in dense OTDM-WDM systems. When
signal pulse widths and optical filter bandwidths are optimized, there is no upper limit to the WDM channel bit rate (BR)
in the purely linear back-to-back configuration. Here, RZ-DPSK performed increasingly better than RZ-OOK in a higher spectral
density with Q gain increasing from 3 to 5 dB. In the nonlinear point-to-point configuration, a higher BR leads to increased performance
penalties for both the RZ-DPSK and RZ-OOK, while the RZ-DPSK still outperforms RZ-OOK by up to 4 dB. The results obtained
correlate with conventional results, indicating the potential of the DP-Q as a performance evaluation tool in numerical simulations. 相似文献
217.
A. Ghaffar M. M. Hussan A. Illahi Majeed A. S. Alkanhal Sajjad Ur Rehman M. Y. Naz 《Waves in Random and Complex Media》2018,28(1):35-48
Effects on RCS of perfect electromagnetic conductor (PEMC) sphere by coating with anisotropic plasma layer are studied in this paper. The incident, scattered and transmitted electromagnetic fields are expanded in term of spherical vector wave functions using extended classical theory of scattering. Co and cross-polarized scattered field coefficients are obtained at the interface of free space-anisotropic plasma and at anisotropic plasma-PEMC sphere core by scattering matrices method. The presented analytical expressions are general for any perfect conducting sphere (PMC, PEC, or PEMC) with general anisotropic/isotropic material coatings that include plasma and metamaterials. The behavior of the forward and backscattered radar cross section of PEMC sphere with the variation of the magnetic field strength, incident frequency, plasma density, and effective collision frequency for the co-polarized and the cross polarized fields are investigated. It is also observed from the obtained results that anisotropic layer on PEMC sphere shows reciprocal behavior as compared to isotopic plasma layer on PEMC sphere. The comparisons of the numerical results of the presented analytical expressions with available results of some special cases show the correctness of the analysis. 相似文献
218.
Muhammed Majeed Kalyanam Nagabhushanam Shaheen Majeed Anurag Pande 《液相色谱法及相关技术杂志》2017,40(14):732-740
Introduction: Identification of Oroxylum indicum and Scutellaria baicalensis provides an interesting challenge in selection of biomarker compound to be used in routine analysis. Both plants have similar phytochemical profile and are rich sources of flavones and flavone glycosides. The objective of this study was to prepare the chemical fingerprinting of O. indicum bark and S. baicalensis roots using the liquid chromatography and mass spectroscopy in single chromatographic method. Materials and methods: Extracts prepared using various solvent systems (methanol, aqueous methanol, chloroform, hexane, and water) of both plants were analyzed using C18 reverse phase column with solvent system containing acetonitrile and 0.1% formic acid. Major flavonoids were identified based on mass spectra, fragmentation pattern, and UV spectra. Results: In this article, well-resolved high-performance liquid chromatographic (HPLC) separation in both plant extracts was obtained and chemical fingerprints for both plant extracts were established and flavonoids present (baicalin, oroxylin A-7-O-glucuronide, chrysin-7-O-glucuronide, baicalein, chrysin, oroxylin-A, wogonin, skullcap flavone II) were identified as possible biomarkers. Conclusion: Mass spectrometry coupled with HPLC can be a tool for fingerprinting of various natural products used in dietary supplement industry. The fingerprint developed in the article can be used for quality evaluation as well as identifying possible adulteration of extracts of both the plants. 相似文献
219.
Hadj-Taieb N Tounsi H Chabchoub A Abid N Gargouri A 《Applied biochemistry and biotechnology》2011,165(7-8):1652-1660
Zymogram analysis is a useful tool for the identification of several enzymes. The present study was undertaken to investigate the efficiency gains from the characterization of pectic enzymes on zymograms by staining of pectin-agarose overlays using cetyl trimethyl ammonium bromide also known as cetrimide or CTAB. The method is based on the fact that the enzymatic hydrolysis of the pectic substrates included in the agarose matrix gel inhibited their precipitation by CTAB, leading to the appearance of cleared zones in front of the pectin hydrolases and lyases. Conversely, esterases led to the increase of pectin precipitation. Fungal pectinolytic enzymes were separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and subjected to the zymogram detection technique, using two pectin substances, namely citrus pectin and polygalacturonic acid. Overall, the findings presented in the current study indicate that several elements (ions, salts, pH, temperature, chelators, and reducing agents) may significantly affect the results of zymogram analysis and can, therefore, be employed to enhance the discriminatory and operational potential of the analysis in terms of accurate discrimination between several pectinolytic activities involved and effective implementation of the purification procedures required in the process. 相似文献
220.