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991.
Uchida T Takamiya M Takahashi M Miyashita H Ikeda H Terada T Matsuo Y Shirouzu M Yokoyama S Fujimori F Hunter T 《Chemistry & biology》2003,10(1):15-24
Disruption of the parvulin family peptidyl prolyl isomerase (PPIase) Pin1 gene delays reentry into the cell cycle when quiescent primary mouse embryo fibroblasts are stimulated with serum. Since Pin1 regulates cell cycle progression, a Pin1 inhibitor would be expected to block cell proliferation. To identify such inhibitors, we screened a chemical compound library for molecules that inhibited human Pin1 PPIase activity in vitro. We found a set of compounds that inhibited Pin1 PPIase activity in vitro with low microM IC50s and inhibited the growth of several cancer lines. Among the inhibitors, PiB, diethyl-1,3,6,8-tetrahydro-1,3,6,8-tetraoxobenzo[lmn] phenanthroline-2,7-diacetate ethyl 1,3,6,8-tetrahydro-1,3,6,8-tetraoxo-benzo[lmn] phenanthroline-(2H,7H)-diacetate, had the least nonspecific toxicity. These results suggest that Pin1 inhibitors could be used as a novel type of anticancer drug that acts by blocking cell cycle progression. 相似文献
992.
In order to compare the soil-to-plant transfer factors (TFs) of fallout 137Cs and those of native stable 133Cs, concentrations of these isotopes were determined in various crops and the associated soils collected throughout Japan.
The results showed that TF-137Cs was 11 times higher than TF-native 133Cs for brown rice, while those values were almost the same for leafy vegetables. Possibly, fallout 137Cs would be more mobile and more easily adsorbed by plants than native 133Cs in the soil because a part of the 133Cs is in a soil structure where it is hard to replace with 137Cs. However, 137Cs and native 133Cs have reached an approximately isotopic equilibrium in the bioavailable fraction in the soils, therefore, the TF-native
133Cs can be used for long-term transfer of 137Cs in the environment. 相似文献
993.
The combination effect of L-arginine and NaCl on bitterness suppression of amino acid solutions 总被引:1,自引:0,他引:1
Ogawa T Nakamura T Tsuji E Miyanaga Y Nakagawa H Hirabayashi H Uchida T 《Chemical & pharmaceutical bulletin》2004,52(2):172-177
The purpose of the present study was to quantify the degree of suppression of the bitterness of two amino acids (L-isoleucine (L-Ile), and L-phenylalanine (L-Phe)) which could be achieved by the addition of various test chemicals, and to examine the mechanism of this bitterness suppression. The test chemicals used were two sweeteners (sucrose, aspartame), NaCl, various acidic (L-aspartic acid, L-glutamic acid), or basic (L-histidine, L-lysine and L-arginine) amino acids, tannic acid and phosphatidic acid. The combination of L-arginine (L-Arg) and NaCl together was the most effective in reducing the bitterness of 100 mM L-Ile and L-Phe solutions in human gustatory sensation tests. Even in bitterness of 0.1 mM quinine solution, L-Arg was also successful in reducing the bitterness. This bitterness-suppression effect was specific to L-Arg and not to the other basic amino acids. No comparable taste-masking effect was observed for the acidic amino acids. The artificial taste sensor failed to predict completely the bitterness-suppressing effect of L-Arg. It seems likely that the bitterness-suppressing effect of L-Arg is mediated not only by binding at the receptor site, but also elsewhere in the process of bitterness perception, such as a direct effect on the sodium channel. It is conjectured that the guanidinium group of L-Arg may interact with sodium channels in taste bud membranes. 相似文献
994.
Reaction of chiral homobinuclear Fischer chromium carbene complexes with allyl alcohol in the presence of NaH and the following oxidative demetalation gave alpha-allyl esters in up to 97% ee via [3,3]-sigmatropic rearrangement reaction promoted by the metal 1,3-shift. On the other hand, chiral heterobinuclear tungsten carbene complexes with arene chromium complexes afforded alpha-allyl-beta-hydroxy esters as a major product in up to 92/8 dr by the same reaction sequence. 相似文献
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