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101.
The hypoglycemic and antioxidants activities of the methanol extract of Lepidium sativum seeds was tested in alloxan-induced diabetic male rats. Thirty male albino rats weighing 190–200 g were divided into five groups as follows: negative control, positive control and three diabetic groups treated with three concentrations of L. sativum methanol extract for four weeks. Induction of hyperglycemia in the positive control group increased blood glucose, glycated hemoglobin A1c, immunoglobulins, liver enzyme, lipid peroxide and kidney function, total cholesterol, low-density lipoproteins, very low-density lipoproteins and decreased antioxidants and high-density lipoproteins compared with the negative control. Furthermore, pancreas tissues showed pathological changes compared with the negative control. Treating the diabetic rats with L. sativum methanol extract decreased blood sugar and restored all biochemical and histological changes to the normal. It could be concluded that L. sativum methanol extract succeeded in controlling diabetes, increasing antioxidants and ameliorating lipid profile.  相似文献   
102.
A 2(5H)‐furanone bearing two furyl rings was synthesized. The behavior of this furanone toward some nitrogen nucleophiles, namely, hydrazine hydrate, benzylamine, and ammonium acetate, was studied. The nitrile group at position‐3 of the furanone was utilized to construct thiazolidine ring by the action of thioglycollic acid. The acid hydrazide synthesized from the previous step was allowed to react with some carbonyl compounds, namely, acetonylacetone, acetylacetone, ethyl acetoacetate, ethyl cinnamate, diethylmalonate, phthalic anhydride, benzil, and 4‐methoxybenzaldehyde, to form pyrrole, pyrazole, and pyrazolopyridazine ring systems bearing two furyl groups. The structures of all the products obtained were illustrated from their analytical and spectral data.  相似文献   
103.
Molecular Diversity - 3,5-Diamino-4-(3-trifluoromethylphenyldiazenyl)-1H-pyrazole was used as a starting scaffold for the synthesis of new pyrazole-based heterocycles to study their effects on the...  相似文献   
104.
In this work plastic strain localization, also referred to as necking, of press-hardened ultra-high strength steel is observed using digital speckle correlation. The region of the neck is studied during tensile tests of specimens specially designed to facilitate strain localization at an inner point of the material, thus avoiding edge effects on localization and fracture. By using measurements with a length scale small enough to properly resolve the neck, its growth and shape can be studied. Furthermore, the anisotropy of the material is investigated by examining specimens cut out at different angles to the rolling direction. It is seen that the local fracture strain of specimens cut out along the rolling direction is approximately twice as high as it is for specimens cut out perpendicular to the rolling direction.  相似文献   
105.
106.
In the current study, eight new hybrids of the NSAIDs, ibuprofen and ketoprofen with five pyrrolizine/indolizine derivatives were designed and synthesized. The chemical structures of these hybrids were confirmed by spectral and elemental analyses. The antiproliferative activities of these hybrids (5 μM) was investigated against MCF-7, A549, and HT-29 cancer cell lines using the cell viability assay, MTT assay. The results revealed 4–71% inhibition of the growth of the three cancer cell lines, where 8a,e,f were the most active. In addition, an investigation of the antiproliferative activity of 8a,e,f against MCF-7 cells revealed IC50 values of 7.61, 1.07, and 3.16 μM, respectively. Cell cycle analysis of MCF-7 cells treated with the three hybrids at 5 μM revealed a pro-apoptotic increase in cells at preG1 and cell cycle arrest at the G1 and S phases. In addition, the three hybrids induced early apoptotic events in MCF-7 cells. The results of the molecular docking of the three hybrids into COX-1/2 revealed higher binding free energies than their parent compounds 5a,c and the co-crystallized ligands, ibuprofen and SC-558. The results also indicated higher binding free energies toward COX-2 over COX-1. Moreover, analysis of the binding modes of 8a,e,f into COX-2 revealed partial superposition with the co-crystallized ligand, SC-558 with the formation of essential hydrogen bonds, electrostatic, or hydrophobic interactions with the key amino acid His90 and Arg513. The new hybrids also showed drug-likeness scores in the range of 1.06–2.03 compared to ibuprofen (0.65) and ketoprofen (0.57). These results above indicated that compounds 8a,e,f deserve additional investigation as potential anticancer candidates.  相似文献   
107.
The present study aimed to assess metabolites heterogeneity among four major Cinnamomum species, including true cinnamon (Cinnamomum verum) and less explored species (C. cassia, C. iners, and C. tamala). UPLC-MS led to the annotation of 74 secondary metabolites belonging to different classes, including phenolic acids, tannins, flavonoids, and lignans. A new proanthocyanidin was identified for the first time in C. tamala, along with several glycosylated flavonoid and dicarboxylic fatty acids reported for the first time in cinnamon. Multivariate data analyses revealed, for cinnamates, an abundance in C. verum versus procyandins, dihydro-coumaroylglycosides, and coumarin in C. cassia. A total of 51 primary metabolites were detected using GC-MS analysis encompassing different classes, viz. sugars, fatty acids, and sugar alcohols, with true cinnamon from Malaysia suggested as a good sugar source for diabetic patients. Glycerol in C. tamala, erythritol in C. iners, and glucose and fructose in C. verum from Malaysia were major metabolites contributing to the discrimination among species.  相似文献   
108.
Keratoconus (KC) is a serious disease that can affect people of any race or nationality, although the exact etiology and pathogenic mechanism are still unknown. In this study, thirty-two FDA-approved ophthalmic drugs were exposed to virtual screening using docking studies against both the MMP-2 and MMP-9 proteins to find the most promising inhibitors as a proposed computational mechanism to treat keratoconus. Matrix metalloproteinases (MMPs) are zinc-dependent proteases, and MMP inhibitors (MMPIs) are usually designed to interact with zinc ion in the catalytic (CAT) domain, thus interfering with enzymatic activity. In our research work, the FDA-approved ophthalmic medications will be investigated as MMPIs, to explore if they can be repurposed for KC treatment. The obtained findings of the docking study suggest that atenolol and ampicillin are able to accommodate into the active sites of MMP-2 and MMP-9. Additionally, both exhibited binding modes similar to inhibitors used as references, with an ability to bind to the zinc of the CAT. Molecular dynamic simulations and the MM-GBSA binding free-energy calculations revealed their stable binding over the course of 50 ns. An additional pharmacophoric study was carried out on MMP-9 (PDB ID: 1GKC) using the co-crystallized ligand as a reference for the future design and screening of the MMP-9 inhibitors. These promising results open the door to further biological research to confirm such theoretical results.  相似文献   
109.
Two zinc(II) complexes, DBZ and DBZH4, that have (ZnN3S2) cores and differ in the bridging mode of the ligating backbone, effectively bind to BSA. The binding affinity varies as DBZ > DBZH4 and depends on the ligand structure. At low concentrations, both complexes exhibit dynamic quenching, whereas at higher concentrations they exhibit mixed (static and dynamic) quenching. The energy transfer mechanism from the BSA singlet excited state to DBZ and DBZH4, is highly likely according to steady-state fluorescence and time-correlated singlet photon counting. Molecular docking was used to support the mode of interaction of the complexes with BSA and showed that DBZ had more energy for binding. Furthermore, antibacterial testing revealed that both complexes were active but to a lesser extent than chloramphenicol. In comparison to DBZH4, DBZ has higher antibacterial activity, which is consistent with the binding constants, molecular docking, and particle size of adducts. These findings may have an impact on biomedicine.  相似文献   
110.
Summary The direct electrochemical oxidation of metallic iron, cobalt, nickel and copper in Me2CO solution of benzoylglycine and/or ethylphthaloylglycine gave products with high yields. For each of the complexes, the electrochemical efficiency is commensurate with the metals being divalent. Conventional physical and chemical studies were used to characterize the isolated complexes and octahedral geometry was suggested for them on the basis of magnetic and electronic spectral studies. The i.r. spectra show that the ligands coordinate in a bidentate fashion; the carboxylate ion is monodentate. The molar conductances agree with the complexes being non-electrolytes.  相似文献   
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