| 查看: 203 | 回复: 1 | |||
| 当前主题已经存档。 | |||
[交流]
帮忙翻译一下下呢。有关化学的
|
|||
|
In this study, the in vitro activities of a natural sesquiterpene, a-cyperotundone, isolated from the root bark of Maytenus retusa and a cobalt(II)-complex of a natural occurring prenyl hydroxynaphthoquinone (lapachol) were evaluated against the trophozoite stage of Acanthamoeba castellanii Neff using a previously developed colorimetric 96-well microtiter plate assay, based on the oxido-reduction of Alamar Blue. The obtained activities showed that these two compounds were able to inhibit the in vitro growth of the amoebae at relatively low concentrations. Further identification of the molecular targets of these products and their effects on acanthamoebae should be determined to evaluate their possible therapeutic use. Acanthamoeba species are opportunistic causal agents of disseminated infections (mostly cutaneous and nasopharyngeal infections), such as a sight-threatening ulceration of the cornea called amoebic keratitis and a fatal Acanthamoeba Granulomatous Encephalitis (AGE) (Marciano-Cabral and Cabral, 2003; Clarke and Niederkorn, 2006; Khan, 2006). Present therapeutic measures for Acanthamoeba keratitis rely on topical applications of antimicrobials including a combination of propamidine isothionate and neomycin or chlorhexidine. The length of these treatments makes the process arduous. Furthermore, as present treatments are poorly effective against cystic stages of the protozoan, residual infection often remains even after treatment. No treatment against AGE has been established although therapeutic measures have been used with apparent effect as an adjunct to surgery (Schuster and Visvesvara, 2004; Khan, 2003, 2006; Martín-Navarro et al., 2008). Terpenes represent one of the largest and most diverse classes of secondary metabolites, with over 55,000 members isolated to date. The terpene cyclase enzymes used in nature convert simple, linear hydrocarbon phosphates into an exotic array of chiral, carbocyclic skeletons. Further oxidation and rearrangement results in an almost endless number of conceivable structures. The enormous structural diversity presented by this class of natural products ensures a broad range of biological properties—ranging from anticancer and anti-malarial activities to tumour promotion and ionchannel binding (Paduch et al., 2007; Patocˇka, 2003). The marked structural differences of terpenes also largely thwart the development of any truly general strategies for their synthetic construction (Maimone and Baran, 2007). Furthermore, several sesquiterpenes have shown to be promising for the treatment of infections due to parasitic protozoa such as Plasmodium, Leishmania and Trypanosoma (Karioti et al., 2007; Schmidt et al., 2009). In this work, the in vitro activity of a natural sesquiterpene and a synthetic cobalt( II)–lapachol complex against the trophozoite stage of Acanthamoeba castellanii Neff is reported. The first molecule is a patchoulane-type sesquiterpene, a-cypertundone (Neraldi et al., 1965), isolated from the root bark of Maytenus retusa. The second molecule tested is a cobalt(II)-complex of lapachol. Lapachol is a prenyl hydroxynaphthoquinone with interesting biological properties such as antitumoural and antibiotic (Ravelo et al., 2004). Unfortunately, it has serious negative side effects(de Sandoval et al., 1996). However, and due to some properties such as a good chelating ketoenol function and a prenyl residue making it lipophilic, pharmacologists are still interested in testing lapachol complexes with metal cations. In this work, the activity of a previously synthesized (Hernández- Molina et al., 2007) complex of Co(II) with lapacholate anions was tested. To our knowledge, the present study demonstrates for the first time the in vitro activity of a-cyperotundone and the Co(II)–lapachol complex against A. castellanii Neff. The obtained activities showed that these molecules inhibited the in vitro growth of the amoebae at relatively low concentrations, and thus highlights their future therapeutic use. |
回复此楼» 猜你喜欢
面上可以超过30页吧？
已经有13人回复
-
网上报道青年教师午睡中猝死、熬夜猝死的越来越多，主要哪些原因引起的？
已经有10人回复
-
为什么中国大学工科教授们水了那么多所谓的顶会顶刊，但还是做不出宇树机器人？
已经有13人回复
-
什么是人一生最重要的？
已经有8人回复
-
版面费该交吗
已经有17人回复
-
体制内长辈说体制内绝大部分一辈子在底层，如同你们一样大部分普通教师忙且收入低
已经有19人回复
-
【博士招生】太原理工大学2026化工博士
已经有8人回复
-
280求调剂
已经有4人回复
2楼2010-03-29 14:15:27