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51.
52.
Fatmah A.M. Al-Omary Laila A. Abou-zeid Mahmoud N. Nagi El-Sayed E. Habib Alaa A.-M. Abdel-Aziz Adel S. El-Azab Sami G. Abdel-Hamide Mohamed A. Al-Omar Abdulrahman M. Al-Obaid Hussein I. El-Subbagh 《Bioorganic & medicinal chemistry》2010,18(8):2849-2863
A new series of 2,6-substituted-quinazolin-4-ones was designed, synthesized, and evaluated for their in vitro DHFR inhibition, antimicrobial, and antitumor activities. Compounds 22, 33–37, 39–43, and 45 proved to be active DHFR inhibitors with IC50 range of 0.4–1.0 μM. Compound 18 showed broad-spectrum antimicrobial activity comparable to the known antibiotic gentamicin. Compounds 34 and 36 showed antitumor activity at GI50 (MG-MID) concentrations of 11.2, and 24.2 μM, respectively. Molecular modeling study including flexible alignment; electrostatic, hydrophobic mappings; and pharmacophore prediction were performed. A main featured pharmacophore model was developed which justifies the importance of the main pharmacophoric groups as well as of their relative distances. The substitution pattern and spatial considerations of the π-systems in regard to the quinazoline nucleus proved critical for biological activity. 相似文献
53.
A benzoquinone and flavonoids from Cyperus alopecuroides 总被引:1,自引:0,他引:1
Nassar MI Abdel-Razik AF El-Khrisy Eel-D Dawidar AA Bystrom A Mabry TJ 《Phytochemistry》2002,60(4):385-387
A benzoquinone, named alopecuquinone, was isolated from the ethanol extract of the inflorescences of Cyperus alopecuroides. Its structure was primarily elucidated by spectroscopic analysis including 1H, 13C NMR, APT, HMQC, 1H-1H COSY and CIMS. The known flavonoids, vicenin 2, orientin, diosmetin, quercetin 3,3'-dimethyl ether and its 3,4'-dimethyl ether, were also isolated and characterized. The ethanol extract of the plant material showed moderate estrogenic activity using a strain of Saccharomyces cerevisiae. 相似文献
54.
A neutralizing antibody against human DNA polymerase epsilon inhibits cellular but not SV40 DNA replication. 下载免费PDF全文
H Pospiech I Kursula W Abdel-Aziz L Malkas L Uitto M Kastelli M Vihinen-Ranta S Eskelinen J E Syvoja 《Nucleic acids research》1999,27(19):3799-3804
The contribution of human DNA polymerase epsilon to nuclear DNA replication was studied. Antibody K18 that specifically inhibits DNA polymerase activity of human DNA polymerase epsilon in vitro significantly inhibits DNA synthesis both when microinjected into nuclei of exponentially growing human fibroblasts and in isolated HeLa cell nuclei. The capability of this neutralizing antibody to inhibit DNA synthesis in cells is comparable to that of monoclonal antibody SJK-132-20 against DNA polymerase alpha. Contrary to the antibody against DNA polymerase alpha, antibody K18 against DNA polymerase epsilon did not inhibit SV40 DNA replication in vitro. These results indicate that DNA polymerase epsilon plays a role in replicative DNA synthesis in proliferating human cells like DNA polymerase alpha, and that this role for DNA polymerase epsilon cannot be modeled by SV40 DNA replication. 相似文献
55.
Clunes MT Lindsay SL Roussa E Quinton PM Bovell DL 《Journal of molecular histology》2004,35(4):339-345
The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption. 相似文献
56.
Alaa A.-M. Abdel-Aziz Adel S. El-Azab Nawaf A. AlSaif Mohammed M. Alanazi Manal A. El-Gendy Ahmad J. Obaidullah 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):610-621
Abstract Cyclic imides containing 3-benzenesulfonamide, oxime, and β-phenylalanine derivatives were synthesised and evaluated to elucidate their in vivo anti-inflammatory and ulcerogenic activity and in vitro cytotoxic effects. Most active anti-inflammatory agents were subjected to in vitro COX-1/2 inhibition assay. 3-Benzenesulfonamides (2–4, and 9), oximes (11–13), and β-phenylalanine derivative (18) showed potential anti-inflammatory activities with 71.2–82.9% oedema inhibition relative to celecoxib and diclofenac (85.6 and 83.4%, respectively). Most active cyclic imides 4, 9, 12, 13, and 18 possessed ED50 of 35.4–45.3?mg kg?1 relative to that of celecoxib (34.1?mg kg?1). For the cytotoxic evaluation, the selected derivatives 2–6 and 8 exhibited weak positive cytotoxic effects (PCE = 2/59–5/59) at 10?μM compared to the standard drug, imatinib (PCE = 20/59). Cyclic imides bearing 3-benzenesulfonamide (2–5, and 9), acetophenone oxime (11–14, 18, and 19) exhibited high selectivity against COX-2 with SI > 55.6–333.3 relative to that for celecoxib [SI > 387.6]. β-Phenylalanine derivatives 21–24 and 28 were non-selective towards COX-1/2 isozymes as indicated by their SI of 0.46–0.68. 相似文献
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Elham A. Sammour Fatma M.A. El-Hawary Nahid F. Abdel-Aziz 《Archives Of Phytopathology And Plant Protection》2013,46(7):655-670
Both neemix and basil oil had an insecticidal effect against Aphis craccivora Koch when the plant was treated systematically or by contact. The tested compounds caused a significant reduction in fecundity, longevity and the natal period. In addition, neemix and basil oil had a toxic effect on the adult stage of the pest, which was more clear for basil oil than neemix, since the cumulative percent morality reached 100% in all tested concentrations after 7 days for basil treatment and after 8 days for neemix oil treatment, while the mortality did not exceed 36% for the control. The two tested oils also had an antifeedant and aphicidal effect on the nymphal stage, since they caused prolongation of the nymphal duration, high percentage of mortality and only a few young ones can be succeeded to reach to the adult stage. The correlation between the biological effects of the tested compounds and the impairment of the activity of some enzymes (acid phosphatase and alkaline phosphatase) and (aspartate aminotranferase and alanine aminotransferase) as well as protein contents had also been investigated. The results clarified a significant reduction in all the tested enzymes and were more pronounced for basil oil treatment than neemix. This explained the reduction in the reproductive potency of A. craccivora Koch. Concerning the side effect of the tested compounds on faba bean plants, the results indicated that the treatment induced promising effect on the antioxidant enzymes activity (superoxide dismutase, catalase, peroxidase and polyphenol oxidase) of the plants which were treated with basil oil and neemix. 相似文献