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21.
Mohammed Alqarni Nader Ibrahim Namazi Sameer Alshehri Ibrahim A. Naguib Amal M. Alsubaiyel Kumar Venkatesan Eman Mohamed Elmokadem Mahboubeh Pishnamazi Mohammed A. S. Abourehab 《Molecules (Basel, Switzerland)》2022,27(14)
Industrial-based application of supercritical CO2 (SCCO2) has emerged as a promising technology in numerous scientific fields due to offering brilliant advantages, such as simplicity of application, eco-friendliness, and high performance. Loxoprofen sodium (chemical formula C15H18O3) is known as an efficient nonsteroidal anti-inflammatory drug (NSAID), which has been long propounded as an effective alleviator for various painful disorders like musculoskeletal conditions. Although experimental research plays an important role in obtaining drug solubility in SCCO2, the emergence of operational disadvantages such as high cost and long-time process duration has motivated the researchers to develop mathematical models based on artificial intelligence (AI) to predict this important parameter. Three distinct models have been used on the data in this work, all of which were based on decision trees: K-nearest neighbors (KNN), NU support vector machine (NU-SVR), and Gaussian process regression (GPR). The data set has two input characteristics, P (pressure) and T (temperature), and a single output, Y = solubility. After implementing and fine-tuning to the hyperparameters of these ensemble models, their performance has been evaluated using a variety of measures. The R-squared scores of all three models are greater than 0.9, however, the RMSE error rates are 1.879 × 10−4, 7.814 × 10−5, and 1.664 × 10−4 for the KNN, NU-SVR, and GPR models, respectively. MAE metrics of 1.116 × 10−4, 6.197 × 10−5, and 8.777 × 10−5errors were also discovered for the KNN, NU-SVR, and GPR models, respectively. A study was also carried out to determine the best quantity of solubility, which can be referred to as the (x1 = 40.0, x2 = 338.0, Y = 1.27 × 10−3) vector. 相似文献
22.
Eslam B. Elkaeed Reda G. Yousef Hazem Elkady Ibraheem M. M. Gobaara Bshra A. Alsfouk Dalal Z. Husein Ibrahim M. Ibrahim Ahmed M. Metwaly Ibrahim H. Eissa 《Molecules (Basel, Switzerland)》2022,27(14)
A nicotinamide-based derivative was designed as an antiproliferative VEGFR-2 inhibitor with the key pharmacophoric features needed to interact with the VEGFR-2 catalytic pocket. The ability of the designed congener ((E)-N-(4-(1-(2-(4-benzamidobenzoyl)hydrazono)ethyl)phenyl)nicotinamide), compound 10, to bind with the VEGFR-2 enzyme was demonstrated by molecular docking studies. Furthermore, six various MD simulations studies established the excellent binding of compound 10 with VEGFR-2 over 100 ns, exhibiting optimum dynamics. MM-GBSA confirmed the proper binding with a total exact binding energy of −38.36 Kcal/Mol. MM-GBSA studies also revealed the crucial amino acids in the binding through the free binding energy decomposition and declared the interactions variation of compound 10 inside VEGFR-2 via the Protein–Ligand Interaction Profiler (PLIP). Being new, its molecular structure was optimized by DFT. The DFT studies also confirmed the binding mode of compound 10 with the VEGFR-2. ADMET (in silico) profiling indicated the examined compound’s acceptable range of drug-likeness. The designed compound was synthesized through the condensation of N-(4-(hydrazinecarbonyl)phenyl)benzamide with N-(4-acetylphenyl)nicotinamide, where the carbonyl group has been replaced by an imine group. The in-vitro studies were consonant with the obtained in silico results as compound 10 prohibited VEGFR-2 with an IC50 value of 51 nM. Compound 10 also showed antiproliferative effects against MCF-7 and HCT 116 cancer cell lines with IC50 values of 8.25 and 6.48 μM, revealing magnificent selectivity indexes of 12.89 and 16.41, respectively. 相似文献
23.
Hany Ezzat Khalil Miada F. Abdelwahab Promise Madu Emeka Lorina I. Badger-Emeka Krishnaraj Thirugnanasambantham Hairul-Islam Mohamed Ibrahim Sara Mohamed Naguib Katsuyoshi Matsunami Nada M. Abdel-Wahab 《Molecules (Basel, Switzerland)》2022,27(9)
Diabetes mellitus (DM) is a complicated condition that is accompanied by a plethora of metabolic symptoms, including disturbed serum glucose and lipid profiles. Several herbs are reputed as traditional medicine to improve DM. The current study was designed to explore the chemical composition and possible ameliorative effects of Ocimum forskolei on blood glucose and lipid profile in high-fat diet/streptozotocin-induced diabetic rats and in 3T3-L1 cell lines as a first report of its bioactivity. Histopathological study of pancreatic and adipose tissues was performed in control and treatment groups, along with quantification of glucose and lipid profiles and the assessment of NF-κB, cleaved caspase-3, BAX, and BCL2 markers in rat pancreatic tissue. Glucose uptake, adipogenic markers, DGAT1, CEBP/α, and PPARγ levels were evaluated in the 3T3-L1 cell line. Hesperidin was isolated from total methanol extract (TME). TME and hesperidin significantly controlled the glucose and lipid profile in DM rats. Glibenclamide was used as a positive control. Histopathological assessment showed that TME and hesperidin averted necrosis and infiltration in pancreatic tissues, and led to a substantial improvement in the cellular structure of adipose tissue. TME and hesperidin distinctly diminished the mRNA and protein expression of NF-κB, cleaved caspase-3, and BAX, and increased BCL2 expression (reflecting its protective and antiapoptotic actions). Interestingly, TME and hesperidin reduced glucose uptake and oxidative lipid accumulation in the 3T3-L1 cell line. TME and hesperidin reduced DGAT1, CEBP/α, and PPARγ mRNA and protein expression in 3T3-L1 cells. Moreover, docking studies supported the results via deep interaction of hesperidin with the tested biomarkers. Taken together, the current study demonstrates Ocimum forskolei and hesperidin as possible candidates for treating diabetes mellitus. 相似文献
24.
I. M. El-Deen H. K. Ibrahim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):733-740
Reaction of 2-mercapto-4-hydroxy-5H-[1]-benzopyrano-[4,3- d ]-pyrimidin-5-one ( 3 ) with phenyl isothiocyanate and methyl acrylate yielded the corresponding 2-(substituted)thio-4-hydroxy-5H-[1]-benzopyrano-[4,3- d ]-pyrimidin-5-ones ( 4 , 5 ). Hydrolysis and hydrazinolysis of 5 gave acid derivative 6 , and hydrazone 7 . Treatment of hydrazone 7 with ethyl acetoacetate, diethyl malonate, and phenyl isothiocyanate yielded the corresponding 2-(substituted)thio-4-hydroxy-5H-[1]-benzopyrano- [4,3- d ]-pyrimidin-5-ones ( 8 , 9 , and 11 ). Cyclization of 11 with 2 N NaOH led to 12 . 相似文献
25.
Ibrahim A. Radini 《Liquid crystals》2013,40(12):1417-1430
The synthesis and mesomorphic properties of a systematic range of ortho difluoroterphenyls with a bulky terminal chain are detailed. The bulky terminal chain consists of either a tertiarybutyl group or a trimethylsilyl unit, each separated from the core by a short (dimethylene) chain, with the other terminal chain being either octyloxy or heptyl. The synthesis of the materials was affected efficiently using a combination of low temperature lithiations and palladium-catalysed cross-coupling reactions. Unusually for liquid crystals with bulky terminal chains, the smectic phase stability (particularly smectic C) is upheld by more than the nematic phase stability, and in most cases the smectic C phase stability is actually higher than comparable analogues with conventional unbranched terminal chains. It is postulated that the surprisingly high smectic C phase stability results from a phase separation effect due to the incompatibility of the spherical bulky group and the conventional unbranched terminal chain, hence implying that the smectic ‘layers’ are well defined, and such definition of the layers bodes well for bookshelf geometry in ferroelectric mixtures. 相似文献
26.
Mohamed M. Ibrahim Gaber A.M. Mersal Nagi El-Shafai Mohamed M. Youssef Hanaa Shokry 《Comptes Rendus Chimie》2014,17(10):1013-1022
A dithiolate-containing a carbamate mononuclear cobalt(II) complex namely, [Co(Boc-S)2] (1), was obtained by the reaction of a methanolic solution of cobalt(II) nitrate hexahydrate with two equimolar amounts of the deprotonated form of tert-butyl N-(2-mercaptoethyl)carbamate (Boc-SH). The cobalt(II) complex (1) was characterized in the solid state and in solution by using FT–IR, Raman, UV–visible, and EI–mass spectroscopies, as well as thermal and X-ray diffraction studies. Spectral data showed that the carbamate (Boc-SH) acts as a mono-anionic bidentate ligand coordinating the cobalt(II) ion through two imine nitrogen and two deprotonated thiolate sulfur donor atoms in a distorted tetrahedral geometry. The thermoanalytical data evidence that the complex is stable up to 165 °C and undergoes complete decomposition, resulting in CoO. TEM imaging of the oxide residue shows its nano size clusters, suggesting that the complex (1) may be used as a precursor for nano-oxides. X-ray powder diffraction patterns evidence an isomorphism among the complex. The redox behavior of the cobalt(II) complex was also investigated by cyclic voltammetry. The reaction of the dithiolate cobalt(II) complex (1) with methyl iodide appears to occur intramolecularly with the cobalt-bound dithiolate, forming the cobalt(II)-bound dithioether complex [Co(Boc–SCH3)2]I2 (2), as a dication complex with a clean second-order reaction of 13.24 × 10−2 M−1·s−1. 相似文献
27.
Cucer N Imamoglu N Tozak H Demirtas H Sarac F Tatlisen A Oztürk F 《Micron (Oxford, England : 1993)》2007,38(6):674-679
Traditional criterions are not sufficient to predict accurately the recurrence of transitional cell carcinoma of the urinary bladder. Therefore, we aimed to evaluate the AgNORs via total AgNOR area/nucleus area (TAA/NA) for each cell as a prognostic parameter, in TCC of urinary bladder. Tumor tissues of 20 consecutive cases of male bladder cancer patients were divided into two groups as middle differentiated (LG) and high grade (HG). The extra-tumoral tissue (ETT) samples of 10 males served as control group. A second control group (HC) consisted of five healthy and normal bladder tissue samples. The 3 microm of sections from each paraffin embedded tumoral, extra-tumoral and normal tissue samples served as patient and control groups. After deparaffinization and rehydratation steps, silver (AgNO(3)) staining of nucleolar organizer regions-associated proteins (AgNORs) was performed. Instead of Giemsa stain, we used Hematoxylin for contra staining. The images of the 100 analyzable nuclei from each tissue sample, transferred by means of a video camera and video capture card from microscope and recorded onto a computer. Software was prepared in Delphi language for analysis. Mean (E+02) TAA/NA values of HC, ETT, LG and HG groups were 6.97+2.80, 5.70+1.82, 7.80+3.22 and 9.24+3.88, respectively. Statistical comparisons have shown significant differences between all groups.In conclusion, mean TAA/NA per cell has a potential to be a prognostic parameter. Therefore, further evaluation of big patient series will be useful. 相似文献
28.
29.
Nouria A. Al-Awadi Mohamed H. Elnagdi Tommy Mathew Ibrahim El-Gamry Mervat Abdel Khalik 《国际化学动力学杂志》1996,28(10):741-748
Pyrolysis of the Schiff bases of 1-arylmethyleneamino-1,2-dihydro-4,6-dimethyl-2-oxopyridine-3-carbonitriles (1–5) has been studied. These compounds eliminate via a six-membered transition state to produce substituted benzonitriles and 2-hydroxy-4,6-dimethylpyridine-3-carbonitrile. These eliminations are unimolecular first-order reactions. The kinetic data gave a good correlation with σ0 values of the substituents on the aryl group with ρ = 0.83 at 520 K. Utilization of the pyrolytic reaction in synthesis of various benzonitriles is considered, and mechanistic information has been obtained by comparing the kinetic data and product analysis of the Schiff bases with their open-chain substituted benzaldehyde cyanoacetylhydrazones (6–9) analogues. © 1996 John Wiley & Sons, Inc. 相似文献
30.
Shahzad Hussain Abdellatif A. Mohamed Mohamed S. Alamri Mohamed A. Ibraheem Akram A. Abdo Qasem Tawfiq Alsulami Ibrahim A. Ababtain 《Molecules (Basel, Switzerland)》2022,27(3)
This study was planned to explore the locally available natural sources of gum hydrocolloids as a natural modifier of different starch properties. Corn (CS), sweet potato (SPS), and Turkish bean (TBS) starches were mixed with locally extracted native or acetylated cactus (CG) and acacia (AG) gums at 2 and 5% replacement levels. The binary mixtures (starch–gums) were prepared in water, freeze dried, ground to powder, and stored airtight. A rapid viscoanalyzer (RVA), differential scanning calorimeter (DSC), texture analyzer, and dynamic rheometer were used to explore their pasting, thermal, textural, and rheological properties. The presence of acetylated AG or CG increased the final viscosity (FV) in all three starches when compared to starch pastes containing native gums. Plain SPS dispersion had a higher pasting temperature (PT) than CS and TBS. The addition of AG or CG increased the PT of CS, SPS, and TBS. The thermograms revealed the overall enthalpy change of the starch and gum blends: TBS > SPS > CS. The peak temperature (Tp) of starches increased with increasing gum concentration from 2 to 5% for both AG and CG native and modified gums. When compared to the control gels, the addition of 2% CG, either native or modified, reduced the syneresis of starch gels. However, further addition (5% CG) increased the gels’ syneresis. Furthermore, the syneresis for the first cycle on the fourth day was higher than the second cycle on the eighth day for all starches. The addition of native and acetylated CG reduced the hardness of starch gels at all concentrations tested. All of the starch dispersions had higher G′ than G″ values, indicating that they were more elastic and less viscous with or without the gums. The apparent viscosity of all starch gels decreased as shear was increased, with profiles indicating time-dependent thixotropic behavior. All of the starch gels, with or without gums, showed a non-Newtonian shear thinning trend in the shear stress vs. shear rate graphs. The addition of acetylated CG gum to CS resulted in a higher activation energy (Ea) than the native counterparts and the control. More specifically, starch gels with a higher gum concentration (5%) provided greater Ea than their native counterparts. 相似文献