排序方式: 共有65条查询结果,搜索用时 15 毫秒
61.
Gibbs PE Miralem T Lerner-Marmarosh N Tudor C Maines MD 《The Journal of biological chemistry》2012,287(2):1066-1079
62.
Tihomir Tomašić Nace Zidar Veronika Rupnik Andreja Kovač Didier Blanot Stanislav Gobec Danijel Kikelj Lucija Peterlin Mašič 《Bioorganic & medicinal chemistry letters》2009,19(1):153-157
Mur ligases catalyze the biosynthesis of the UDP-MurNAc-pentapeptide precursor of peptidoglycan, an essential polymer of bacterial cell-wall. They constitute attractive targets for the development of novel antibacterial agents. Here we report on the synthesis of a series of 2,4-diaminoquinazolines, quinazoline-2,4(1H,3H)-diones, 5-benzylidenerhodanines and 5-benzylidenethiazolidine-2,4-diones and their inhibitory activities against MurD from Escherichia coli. Compounds (R)-27 and (S)-27 showed inhibitory activity against MurD with IC50 values of 174 and 206 μM, respectively, which makes them promising starting points for optimization. 相似文献
63.
Sandra Sobočanec Željka Mačak Šafranko Ana Šarić Marina Korolija Marijana Popović Hadžija Tihomir Balog 《Biochemistry and Biophysics Reports》2016
Beside classical antioxidative enzymes, the response to hyperoxia might be mediated via regulation of other systems, such as heme oxygenase (HO). Ho-1 gene expression is found to be upregulated by hyperoxia in all groups of mice, while HO-1 protein isoform was increased only in 4 months old male mice. In steady-state conditions ho-1 and ho-2 gene expression remained unchanged irrespective of sex or age, which was not the case with protein level of both isoforms. This study suggests that in lungs of CBA mice the response to oxidative stress may be mediated through the interaction of other systems such as heme oxygenase, primarily via upregulation of ho-1 gene expression in both sexes. Contrary to our previous study in liver of hyperoxia treated mice, current results might imply that at conventional oxygen conditions lungs of female mice with the emphasis on aging females, are better prepared for oxidative stress conditions through the increase of HO-activity. 相似文献
64.
Siân E. C. Davies Masaki Gotoh Douglas A. Richards Tihomir P. Obrenovitch 《Neurochemical research》1998,23(8):1021-1025
We previously showed that extracellular levels of N-acetylaspartate (NAA) increase when a medium with reduced NaCl concentration is perfused through a microdialysis probe, and proposed that NAA may be released during hypoosmotic swelling. Here, we demonstrate that this effect is due to hypoosmolarity of the perfusion medium, and not to low NaCl. NAA changes in the dialysate were compared with those of taurine as the osmoregulatory role of this amino acid is established. Reduction of the NaCl concentration in the perfusion medium increased the dialysate levels of NAA and taurine, but this effect was abolished when NaCl was replaced by sucrose to maintain isosmolarity. The NAA response to hypoosmolarity was smaller than that of taurine, but it may still be important to neurons as NAA is predominantly neuronal in the mammalian CNS. 相似文献
65.
Evidence Disputing the Link Between Seizure Activity and High Extracellular Glutamate 总被引:7,自引:2,他引:5
Abstract: As seizures in experimental models can be induced by the activation and suppressed by the inhibition of glutamate receptors, it is often proposed that a high extracellular glutamate level subsequent to excessive presynaptic release and/or altered glutamate uptake is epileptogenic. The purpose of this study was to ascertain the link between seizure activity and high extracellular glutamate. To assist the detection of any putative rise in extracellular glutamate during seizures, microdialysis was coupled to enzyme-amperometric detection of glutamate, which provides maximal sensitivity and time resolution. Electrical activity and field potential were also recorded through the dialysis membrane to confirm that epileptic activity was present at the sampling site. No increase in dialysate glutamate content was detected during picrotoxin-induced seizures, even when the K+ concentration in the perfusion medium was raised to 50% above that measured previously during paroxysmal activity. In addition, sustained inhibition of glutamate uptake by l - trans -pyrrolidine-2,4-dicarboxylate increased the extracellular glutamate level >20-fold but did not produce electrophysiological changes indicative of excessive excitation. These findings indicate that seizures are not necessarily accompanied by an increased extracellular glutamate level and that increased glutamatergic excitation in epilepsy may result from other abnormalities such as increased density of glutamate receptors, enhanced activation subsequent to reduced modulation, or sprouting of glutamatergic synapses. 相似文献