Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:5.99.1.2 (topoisomerase)
 9,166 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The nuclear factor kappaB (NF-kappaB) is involved in T cell activation and enhances HIV-1 gene expression. It is activated in response to numerous stimuli, including oxidative stress. Oxidative stress damages membrane lipids, proteins and nucleic acids. We have shown previously that oxidative DNA damage generated by photosensitization could trigger activation of NF-kappaB. We now show that a series of topoisomerase poisons (actinomycin D, camptothecin, daunomycin and etoposide) also activate NF-kappaB (NFKB1/RelA dimer) in ACH-2 and CEM cells. This activation is inhibited by pyrrolidine dithiocarbamate. In ACH-2 cells latently infected by HIV-1, camptothecin, daunomycin and etoposide are able to enhance virus production. Since topoisomerase poisons cause the formation of single- and double-strand breaks in DNA, these lesions might be capable of triggering NF-kappaB activation. Indeed, DNA damaging agents generating adducts (trans-platin and 4-nitroquinoline 1-oxide) and/or crosslinks in DNA (cisplatin and mitomycin C) do not or only weakly activate NF-kappaB in T cell lines.
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PMID:Topoisomerase poisons activate the transcription factor NF-kappaB in ACH-2 and CEM cells. 893 79

Gemifloxacin is a novel antibiotic and the first fluoroquinolone with a pyrrolidine derivative at the C-7 position. Because of the added pyrrolidine substitute, gemifloxacin has an enhanced spectrum of activity against Gram-positive bacteria such as Streptococcus pneumoniae and Staphylococcus aureus, in addition to its activity against Gram-negative bacteria. Like other fluoroquinolones, gemifloxacin's mechanism of action focuses on inhibiting DNA gyrase and topoisomerase, thus preventing cellular replication. In addition, in vitro and in vivo data have shown that the compound exhibits excellent activity against Enterobacteriaceae and other respiratory pathogens. Furthermore, it has been demonstrated that gemifloxacin has potential activity in vitro against anaerobic bacteria. With a broad spectrum of activity, convenient once-daily administration, good bio-availability and tolerability, gemifloxacin will be an important addition to our armamentarium against a wide range of infections, from urinary tract infections to community-acquired pneumonia. (c) 2001 Prous Science. All rights reserved.
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PMID:Gemifloxacin. 1276 26

A series of novel 9(10H)-acridinone derivatives with terminal amino substituents at C2 position on the acridinone ring were synthesized and studied for their antiproliferative activity and underlying mechanisms. These compounds demonstrated promising cytotoxicity to leukemia cells CCRF-CEM, displaying IC(50) values in the low micromolar range. Structure-activity relationships (SAR) indicated that the compound 6d bearing a pyrrolidine substituent and 8a with a methyl ammonium side chain displayed higher cytotoxicity to CCRF-CEM cells and also solid tumor cells A549, HepG2, and MCF7. Furthermore, the compounds 6d and 8a had strong binding activity to calf thymus DNA (ct DNA), as detected by UV absorption and fluorescence quenching assays, but limited inhibitory activity to human topoisomerase 1 (topo 1). Taken together, this study discovered a series of new synthetic 9(10H)-acridinone derivatives with potent DNA binding and anticancer activity.
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PMID:Novel synthetic 2-amino-10-(3,5-dimethoxy)benzyl-9(10H)-acridinone derivatives as potent DNA-binding antiproliferative agents. 2086 10

Search for new antimicrobial agents led to the synthesis of series of N-1, C-3 and C-5 substituted bis-indoles. Their evaluation for antifungal and antibacterial activities resulted in the optimization of pyrrolidine/morpholine/N-benzyl moiety at the C-3 end and propane/butane/xylidine groups as linkers between two indoles for significant inhibition of microbial growth. Preliminary investigations have identified three highly potent antimicrobial agents. Dockings of these molecules in the active sites of lanosterol demethylase, dihydrofolate reductase and topoisomerase II indicate their strong interactions with these enzymes.
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PMID:Synthesis and evaluation of indole-based new scaffolds for antimicrobial activities--identification of promising candidates. 2152 74