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31.
Undoped and cobalt-doped sodium phosphate glasses of various compositions and with varying cobalt contents were prepared. UV-visible absorption spectra were measured before and after successive gamma irradiation. Experimental results indicated that the undoped base glass reveals strong ultraviolet absorption which is related to the presence of unavoidable trace iron impurities in the raw materials. Cobalt-doped glasses show characteristic visible absorption bands which are related to the presence of Co2+ ions mostly in the tetra-coordination state. The generated induced color centers in the UV and visible regions by gamma irradiation are characterized in relation to intrinsic defects from the host base sodium phosphate glass and the extrinsic defects from both trace iron impurities and added doped cobalt ions. Infrared absorption measurements were carried out for some selected samples to identify the structural building groups in the studied glasses. Cobalt ions showed a shielding behavior towards the effects of progressive gamma irradiation especially in the visible spectral region. 相似文献
32.
El-Shafey Aya El Din Reham Shams Abdelazim Sarah H. Mamdouh Nahla salah Dina El-Dek S. I. Zaki A. H. 《Journal of Sol-Gel Science and Technology》2021,99(2):326-338
Journal of Sol-Gel Science and Technology - ZnO nanoparticles with different morphologies were prepared via the biotemplate method. The microstructure of synthesized nanoparticles was found to... 相似文献
33.
Zehbah Ali Al-Ahmed Ibrahim H. I. Habib Reham R. Khattab Reda M. Abdelhameed Mohamed El-Naggar Moursi H. Abu Bieh Sergey A. Pisarevd Andrey Voronkov Mardia T. El Sayed 《Journal of heterocyclic chemistry》2021,58(1):127-136
Absorption spectra of tetrahydro[3,2-b]indolocarbazoles (THICZs) with respective molecular property and alkyl substituents have been prerecorded in diverse solvents in the scope between 200 and 600 nm for very fewer times in the literary study. The photo-physical behavior of liquified THICZs belonging to the existence surroundings. The solvatochromic behaviors of THICZs and solvent substance physical phenomenon can be analyzed by implementation of linear solvating energy state conception. Compound 4 shows excellent properties for sensing small molecules. The electrochemical behavior of some THICZs was investigated at carbon paste electrode where two electrode reactions were involved, irreversible oxidation-one electron transfer and quasi-reversible redox reactions forming phenolic followed by quinolone moiety electro active species. The density functional theory which means calculated molecular orbital energies (B3LYP/6-31G) and HOMO-LUMO gap/space for some presented indolocarbazoles have been performed. 相似文献
34.
El-Mahdy Reham I. Mostafa Mohammed Mahmoud EL-Deen Hanan Sharaf 《Applied biochemistry and biotechnology》2019,188(1):208-224
Applied Biochemistry and Biotechnology - Despite advances in the management of cardiovascular diseases, acute coronary syndrome (ACS) remains the leading cause of death worldwide. ACS is associated... 相似文献
35.
Study of the chemical structure and the microbial effect of iron(III) metal ions with four consecutive generations of quinolones in a nanometric form for the purpose of increasing the efficacy of antibacterial and antifungal drugs
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A new series of iron(III) complexes with different fourth generation of quinolone drugs of the type [Fe(L)n(Cl)x]?yH2O (( 1 ) L: nalidixic acid, n = 3, x = 3, y = 3; ( 2 ) L: oxolonic acid, n = 3, x = 3, y = 0; ( 3 ) L: pipemidic acid, n = 3, x = 3, y = 2; ( 4 ) L: lomefloxacin, n = 3, x = 3, y = 0; ( 5 ) L: pefloxacin mesylate, n = 3, x = 3, y = 2; ( 6 ) L: levofloxacin, n = 3, x = 3, y = 6) were synthesized and identified using microanalysis, Fourier transform infrared spectroscopy, conductance data, effective magnetic moments and electronic UV–visible spectra. In these six complexes, the quinolone drug chelates act in a unidentate manner via nitrogen atom of pyridone/piperazyl moiety. Electronic spectroscopic data are in agreement with an octahedral geometrical structure. Thermal degradation analyses in nitrogen gas were used to investigate the number and location of water molecules. The thermal decomposition process is completed in 3?5 steps, the first step being responsible for loss of uncoordinated water molecules and the steady state of all complexes occurs at around 500 °C with oxide forms as residual products. The stabilities of iron(III) complexes 1 – 6 were studied in terms of activation energy E*, entropy ΔS*, enthalpy ΔH* and Gibbs free energy ΔG* that were estimated using Coats–Redfern and Horowitz–Metzger non‐isothermal methods. Molecular docking was used to predict the binding between some of the quinolone drugs and the receptor of prostate cancer 2q7k hormone. 相似文献
36.
Reham Z. Hamza Samy M. EL-Megharbel Tariq Altalhi Adil A. Gobouri Ashjan Ayad Alrogi 《应用有机金属化学》2020,34(3):e5458
The potential benefit of selenium nanoparticles (SeNPs) and vitamin E (Vit.E) that they are potent antioxidants , they were used as antioxidants against acrylamide (ACR) hepatotoxicity, ACR is found in the starchy foods that had been heated for long periods in high degrees above 120°C. So the aim of the current study was to elucidate the antihyperlipidemic and hepatoprotective effects of either SeNPs and/or Vit.E against ACR toxicity, SeNPs were characterized by SEM, EDX, TEM and they proved their spherical nanostructure. Zeta potential value was –22.9 mv with particle size with a diameter range (48.75-67.24 nm) which proved the high stability of the used SeNPs. Seven groups of male mice were used: group I was control,group II ACR,group III was treated with SeNPs, IV group was received Vit.E and groups V,VI received ACR plus SeNPs and ACR plus Vit.E, group VII was given combination of SeNPs and Vit.E plus ACR,So,The effect of SeNPs and/or Vit.E were monitored against ACR hepatotoxicity and hyperlipidemia. ACR administration afforded significant elevation in the hepatic enzymes with severe alterations in the lipid metabolism. These findings clarified the efficacy of SeNPs and Vit.E by declining the high hepatic enzymes activities induced by ACR along with improving the lipid profile, elevation of the antioxidant enzymes (SOD,CAT and GRx), reduction of MDA level, improving histological and ultrastructutral hepatic tissues and restoration of most normal structures that were damaged in ACR group. So, SeNPs and/or Vit.E were proved to enhance the hepatic antioxidant capacities. 相似文献
37.
Mohammad Asif Sherwani Kevin Yang Aditi Jani Reham A. Abed Abdul Karim Taufique Tolulope Gid Dosunmu Nabiha Yusuf 《Photochemistry and photobiology》2019,95(2):605-611
UVA irradiation is known to cause photoaging via production of reactive oxygen species (ROS) and activation of inflammatory processes. Previously, we have demonstrated that baicalin, a plant‐derived flavonoid possessing both antioxidant and anti‐inflammatory activity, protects mouse keratinocytes against damage from UVB irradiation. However, the role of baicalin in vivo has not been well studied, particularly in the setting of UVA irradiation. To explore the protective effects and mechanisms of baicalin treatment in mice after UVA irradiation, mice were exposed to acute and chronic doses of UVA irradiation with or without baicalin or vehicle. Skin samples were collected for histological staining, RNA isolation, flow cytometry and protein extraction. Our results demonstrate the protective effect of baicalin against UVA‐induced oxidative damage and inflammation in mouse skin. These effects are likely mediated via the TLR4 pathway, which may serve as a target for photochemoprevention against skin inflammation. 相似文献
38.
Nasser A. Hassan Asma K. Alshamari Allam A. Hassan Mohamed G. Elharrif Abdullah M. Alhajri Mohammed Sattam Reham R. Khattab 《Molecules (Basel, Switzerland)》2022,27(15)
Alzheimer’s disease (AD) is a chronic dysfunction of neurons in the brain leading to dementia. It is characterized by gradual mental failure, abnormal cognitive functioning, personality changes, diminished verbal fluency, and speech impairment. It is caused by neuronal injury in the cerebral cortex and hippocampal area of the brain. The number of individuals with AD is growing at a quick rate. The pathology behind AD is the progress of intraneuronal fibrillary tangles, accumulation of amyloid plaque, loss of cholinergic neurons, and decrease in choline acetyltransferase. Unfortunately, AD cannot be cured, but its progression can be delayed. Various FDA-approved inhibitors of cholinesterase enzyme such as rivastigmine, galantamine, donepezil, and NDMA receptor inhibitors (memantine), are available to manage the symptoms of AD. An exhaustive literature survey was carried out using SciFinder’s reports from Alzheimer’s Association, PubMed, and Clinical Trials.org. The literature was explored thoroughly to obtain information on the various available strategies to prevent AD. In the context of the present scenario, several strategies are being tried including the clinical trials for the treatment of AD. We have discussed pathophysiology, various targets, FDA-approved drugs, and various drugs in clinical trials against AD. The goal of this study is to shed light on current developments and treatment options, utilizing phytopharmaceuticals, nanomedicines, nutraceuticals, and gene therapy. 相似文献
39.
Aisha M. H. Al-Rajhi Reham Yahya Tarek M. Abdelghany Mohamed A. Fareid Alawlaqi M. Mohamed Basma H. Amin Abdurrahman S. Masrahi 《Molecules (Basel, Switzerland)》2022,27(10)
Natural origin molecules represent reliable and excellent sources to overcome some medicinal problems. The study of anticancer, anticoagulant, and antimicrobial activities of Thevetia peruviana latex were the aim of the current research. An investigation using high-performance liquid chromatography (HPLC) revealed that the major content of the flavonoids are rutin (11.45 µg/mL), quersestin (7.15 µg/mL), naringin (5.25 µg/mL), and hisperdin (6.07 µg/mL), while phenolic had chlorogenic (12.39 µg/mL), syringenic (7.45 µg/mL), and ferulic (5.07 µg/mL) acids in latex of T. peruviana. Via 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging, the experiment demonstrated that latex had a potent antioxidant activity with the IC50 43.9 µg/mL for scavenging DPPH. Hemolysis inhibition was 58.5% at 1000 µg/mL of latex compared with 91.0% at 200 µg/mL of indomethacin as positive control. Negligible anticoagulant properties of latex were reported where the recorded time was 11.9 s of prothrombin time (PT) and 29.2 s of the activated partial thromboplastin time (APTT) at 25 µg/mL, compared with the same concentration of heparin (PT 94.6 s and APPT 117.7 s). The anticancer potential of latex was recorded against PC-3 (97.11% toxicity) and MCF-7 (96.23% toxicity) at 1000 μg/mL with IC50 48.26 μg/mL and 40.31 µg/mL, respectively. Disc diffusion assessment for antimicrobial activity recorded that the most sensitive tested microorganisms to latex were Bacillus subtilis followed by Escherichia coli, with an inhibition zone (IZ) of 31 mm with minimum inhibitory concentration (MIC) (10.2 μg/mL) and 30 mm (MIC, 12.51 μg/mL), respectively. Moreover, Candida albicans was sensitive (IZ, 28 mm) to latex, unlike black fungus (Mucor circinelloides). TEM examination exhibited ultrastructure changes in cell walls and cell membranes of Staphylococcus aureus and Pseudomonas aeruginosa treated with latex. Energy scores of the molecular docking of chlorogenic acid with E. coli DNA (7C7N), and Rutin with human prostate-specific antigen (3QUM) and breast cancer-associated protein (1JNX), result in excellent harmony with the experimental results. The outcome of research recommended that the latex is rich in constituents and considered a promising source that contributes to fighting cancer and pathogenic microorganisms. 相似文献
40.
In this research, copper (II) oxide nanoparticles were prepared by an ecofriendly green method using the extract of corchorus olitorus leaves (Molokhaia) as a surfactant, capping and anti-agglomeration agent. The ecofriendly green CuO NPs were characterized using different chemical and physical techniques and the results confirmed the formation of monoclinic tenorite CuO nanoparticles with an average particle size of 12 nm and BET surface area of 11.1 m2/g. The eco-friendly green CuO NPs were used in environmental remediation for the efficient catalytic degradation of direct violet dye via advanced oxidation process (AOP) in presence of H2O2. The impact of AOP environmental parameters affecting the degradation process was investigated. Moreover, the catalytic degradation of the direct violet dye using the ecofriendly green CuO NPs was studied kinetically and thermodynamically and the results showed that the catalytic degradation process agreed well with the pseudo-second-order kinetic model and the process was spontaneous and endothermic in nature. Finally, high catalytic degradation of the direct violet dye was observed when the eco-friendly prepared green CuO NPs were placed in real water samples. 相似文献