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91.
Heba A. Hassan Mohamed Abdel-Aziz Gamal El-Din A.A. Abuo-Rahma Hassan H. Farag 《Bioorganic & medicinal chemistry》2009,17(4):1681-1692
A group of 1-malonyl-1,4-dihydropyridine derivatives were synthesized as novel carrier systems for site-specific and sustained drug delivery to the brain. Such carriers are expected to be stable against air oxidation due to the presence of the carbonyl group close to nitrogen of the dihydropyridine. These carrier systems were attached to a group of different aldehydes to afford novel quaternary pyridinium derivatives 9a–e, 11a–d, 13 and 18a–b. Reduction of the prepared quaternary pyridinium derivatives with sodium dithionite afforded a novel group of 1-malonyl-1,4-dihydropyridine chemical delivery systems (CDSs) 10a–e, 12a–d, 14 and 19a–b. The synthesized 1-malonyl-1,4-dihydropyridine CDSs were subjected to various chemical and biological investigations to evaluate their ability to cross the blood–brain barrier, and to be oxidized biologically into their corresponding quaternary derivatives. The in vitro oxidation studies showed that most of the 1-malonyl-1,4-dihydropyridine CDSs could be oxidized into their corresponding quaternary derivatives at an adequate rate. The in vivo studies showed that compounds 10c and 14 were able to cross the blood–brain barrier at detectable concentrations. Moreover, the pyridinium quaternary intermediates 9a, 9c, 13, 18a and their corresponding dihydro derivatives 10a, 10c, 14 and 19a were screened for their antidepressant activity using tail suspension behavioral despair test compared to imipramine as a reference at a dose level of 10 mg/kg. The results indicated that compounds 13, 14 and 19a induced remarkable antidepressant activity comparable to imipramine. Compounds 10a, 10c and 18a exhibited good antidepressant activity, their activities nearly equal to 92.8%, 86.7% and 90.20% of the activity of imipramine, respectively. The other derivatives 9a and 9c exhibited moderate antidepressant activity compared with imipramine. 相似文献
92.
Mamdooh H. Ghoneum Nariman K. Badr El-Din Salma M. Abdel Fattah Deyu Pan Lucilene Tolentino 《International journal of biological sciences》2015,11(3):295-303
In the current study, we examined the protective effect of hydroferrate fluid MRN-100 against the carcinogen methylnitronitrosoguanidine (MNNG)-induced gastric and esophageal cancer in rats. MRN-100 is an iron-based compound composed of bivalent and trivalent ferrates. At 33 weeks post treatment with MNNG, rats were killed and examined for the histopathology of esophagus and stomach; liver, spleen, and total body weight; and antioxidant levels in the blood and stomach tissues. Results showed that 17/20 (85%) gastroesophageal tissues from carcinogen MNNG-treated rats developed dysplasia and cancer, as compared to 8/20 (40%) rats treated with MNNG plus MRN-100. In addition, MRN-100 exerted an antioxidant effect in both the blood and stomach tissues by increasing levels of GSH, antioxidant enzymes SOD, CAT, and GPx, and total antioxidant capacity (TAC) level. This was accompanied by a reduction in the total free-radical and malondialdehyde levels. Furthermore, MRN-100 protected against body and organ weight loss. Thus, MRN-100 exhibited significant cancer chemopreventive activity by protecting tissues against oxidative damage in rats, which may suggest its effectiveness as an adjuvant for the treatment of gastric/esophageal carcinoma. 相似文献
93.
Faruk Eman Mohamed Sabry Dina Morsi Ahmed A. El-Din Yasmine Alaa Taha Neama M. Medhat Engy 《Molecular and cellular biochemistry》2022,477(1):53-65
Molecular and Cellular Biochemistry - The era of induced pluripotent stem cells (iPSCs) was used as novel biotechnology to replace embryonic stem cells bypassing the ethical concerns and problems... 相似文献
94.
Ahmed F. Essa Seham S. El-Hawary Tahia M. Kubacy Ezz El-Din A. M. El-Khrisy Ahmed H. El-Desoky Abdelsamed I. Elshamy Inas Y. Younis 《化学与生物多样性》2023,20(2):e202200918
In spite of tremendous efforts exerted in the management of COVID-19, the absence of specific treatments and the prevalence of delayed and long-term complications termed post-COVID syndrome still urged all concerned researchers to develop a potent inhibitor of SARS-Cov-2. The hydromethanolic extracts of different parts of E. mauritanica were in vitro screened for anti-SARS-Cov-2 activity. Then, using an integrated strategy of LC/MS/MS, molecular networking and NMR, the chemical profile of the active extract was determined. To determine the optimum target for these compounds, docking experiments of the active extract's identified compounds were conducted at several viral targets. The leaves extract showed the best inhibitory effect with IC50 8.231±0.04 μg/ml. The jatrophane diterpenes were provisionally annotated as the primary metabolites of the bioactive leaves extract based on multiplex of LC/MS/MS, molecular network, and NMR. In silico studies revealed the potentiality of the compounds in the most active extract to 3CLpro, where compound 20 showed the best binding affinity. Further attention should be paid to the isolation of various jatrophane diterpenes from Euphorbia and evaluating their effects on SARS-Cov-2 and its molecular targets. 相似文献
95.
Tamer M. Gamal El-Din Gilbert Q. Martinez Jian Payandeh Todd Scheuer William A. Catterall 《The Journal of general physiology》2013,142(3):181-190
Voltage-gated sodium channels undergo slow inactivation during repetitive depolarizations, which controls the frequency and duration of bursts of action potentials and prevents excitotoxic cell death. Although homotetrameric bacterial sodium channels lack the intracellular linker-connecting homologous domains III and IV that causes fast inactivation of eukaryotic sodium channels, they retain the molecular mechanism for slow inactivation. Here, we examine the functional properties and slow inactivation of the bacterial sodium channel NavAb expressed in insect cells under conditions used for structural studies. NavAb activates at very negative membrane potentials (V1/2 of approximately −98 mV), and it has both an early phase of slow inactivation that arises during single depolarizations and reverses rapidly, and a late use-dependent phase of slow inactivation that reverses very slowly. Mutation of Asn49 to Lys in the S2 segment in the extracellular negative cluster of the voltage sensor shifts the activation curve ∼75 mV to more positive potentials and abolishes the late phase of slow inactivation. The gating charge R3 interacts with Asn49 in the crystal structure of NavAb, and mutation of this residue to Cys causes a similar positive shift in the voltage dependence of activation and block of the late phase of slow inactivation as mutation N49K. Prolonged depolarizations that induce slow inactivation also cause hysteresis of gating charge movement, which results in a requirement for very negative membrane potentials to return gating charges to their resting state. Unexpectedly, the mutation N49K does not alter hysteresis of gating charge movement, even though it prevents the late phase of slow inactivation. Our results reveal an important molecular interaction between R3 in S4 and Asn49 in S2 that is crucial for voltage-dependent activation and for late slow inactivation of NavAb, and they introduce a NavAb mutant that enables detailed functional studies in parallel with structural analysis. 相似文献
96.
Khadiga S. Abdulaziz Rehab Tareq Mohamad Lama Saad El-Din Mahmoud Tarek Abdel Azim Ramzy Doaa A. Osman 《Journal of musculoskeletal & neuronal interactions》2021,21(1):121
Objectives:To determine the effect of neurogenic acupoint dry cupping therapy on high sensitive C-reactive protein (hs-CRP) level, pain perception & intensity, and life impact of pelvic pain in women with chronic pelvic pain (CPP), with regard to the biological and neurophysiological impacts of dry cupping on acupoint.Methods:Thirty women with CPP were randomly divided into two equal groups; the study group received dry cupping on neurogenic acupoints plus lifestyle modifications for 8 weeks (n=15), while the control group received only lifestyle modifications for 8 weeks (n=15). Women were assessed pre- and post-rehabilitation program with the hs-CRP blood test, the short-form McGill Pain Questionnaire (SF-MPQ), and the pelvic pain impact questionnaire (PPIQ).Results:Comparing both groups post-treatment revealed that there were significant reductions in levels of hs-CRP, and scores of SF-MPQ & PPIQ (p<0.05) in the study group compared with the control group. Also, there were significant positive correlations between hs-CRP and both SF-MPQ “Visual Analogue Scale (VAS), Present Pain Intensity (PPI) index & Pain Rating Index (PRI)” and PPIQ (p<0.05).Conclusion:Neurogenic acupoint cupping therapy had significantly improving effects on the degree of inflammation, pain perception & intensity, and life impact of pelvic pain in women with CPP. 相似文献
97.
SDS — dissociated proteins from eight isolates belonging to threeFusarium species were assessed and compared using polyacrylamide gel electrophoresis. Intra and inter specific variation in banding patterns were analyzed both qualitatively and quantitatively. Special emphasis was placed on variability of protein banding pattern between two nonpathogenic strains ofF. oxysporum (C5 and C14). Protein profiles from host-associated isolates were distinct, and each isolate showed a uniquely characteristic profile. Attempts were made to provide information on the genetic system controlling pathogenicity, compared to nonpathogenicity, at the protein level. The data obtained from electrophoresis support the potential use of this experimental approach to help distinguish between differentFusarium isolates. 相似文献
98.
Biochemical Decomposition of the Herbicide N-(3,4-Dichlorophenyl)-2-Methylpentanamide and Related Compounds 总被引:4,自引:4,他引:0 下载免费PDF全文
Organisms capable of decomposing N-(3,4-dichlorophenyl)-2-methylpentanamide (Karsil) were isolated, identified, and tested for their ability to hydrolyze this herbicide. Primary products of Karsil decomposition by cells and cell-free extracts of a Penicillium sp. were identified as 2-methyl-valeric acid and 3,4-dichloroaniline. The Karsil acylamidase (EC 3.5.1.a aryl acylamine amidohydrolase) was an induced enzyme. It was partially purified and tested for its ability to hydrolyze 25 related compounds. Some relations between the structures of these compounds and their susceptibility to enzymatic hydrolysis were discerned. 相似文献
99.
Khalid M. Badr El-Din Hesham Salem Sayed Derayea Amany Abdelaziz Dalia M. Nagy 《Luminescence》2023,38(9):1583-1590
A spectrofluorimetric approach that is sensitive, simple, validated, and cost-effective has been proposed for the estimation of amlodipine (AML) and perindopril (PER) in their bulk powders, pharmaceutical formulations, and spiked human plasma. The recommended approach utilized the quantitative quenching effect of the two cited drugs on the fluorescence intensity of erythrosine B, as a result of complex binary reactions among each drug with erythrosine B at pH 3.5 (Teorell and Stenhagen buffer). The quenching of erythrosine B fluorescence was recorded at 554 nm after excitation at 527 nm. The calibration curve was detected in the range 0.25–3.0 μg ml−1, with a correlation coefficient of 0.9996 for AML, and 0.1–1.5 μg ml−1, with a correlation coefficient of 0.9996 for PER. The established spectrofluorimetric approach was validated for the estimation of the cited drugs with high sensitivity regarding International Council on Harmonization guidelines. Therefore, the established approach could be utilized for quality control of the cited drugs in their pharmaceutical formulations. 相似文献
100.