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71.
The presence of beta-endorphin-like immunoreactivity (beta-END-LI) in human gallbladder and its release were examined by means of radioimmunochemical measurements and immunohistochemical stainings. beta-END-LI was detected in the gallbladder (27.2 +/- 3.2 ng/g wet weight, mean +/- S.E.). The immunoreactivity in beta-END-LI extracted from the gallbladder was similar to that of synthetic beta-END, judging from the result of its inhibition curve parallel to that of the synthetic substance in the radioimmunoassay (RIA) system. On gel-filtration chromatography of a gallbladder extract, two components of beta-END-LI were found; one eluted on a position of beta-lipotropin (beta-LPH) and another on a position of synthetic beta-END. Specific beta-END-LI positive cells were detectable in metaplastic mucous glands. When human gallbladder mucosa was perfused with a solution of 10(-8) M or 10(-6) M cholecystokinin octapeptide (CCK-8), the release of beta-END-LI from mucosa into the perfusate increased 2-3 fold. These results indicate that beta-END-LI present in human gallbladder is released by the direct action of CCK-8 on the gallbladder mucosa and suggest that it may have a physiological or pathophysiological role. 相似文献
72.
Periostin induces proliferation of differentiated cardiomyocytes and promotes cardiac repair 总被引:8,自引:0,他引:8
Kühn B del Monte F Hajjar RJ Chang YS Lebeche D Arab S Keating MT 《Nature medicine》2007,13(8):962-969
Adult mammalian hearts respond to injury with scar formation and not with cardiomyocyte proliferation, the cellular basis of regeneration. Although cardiogenic progenitor cells may maintain myocardial turnover, they do not give rise to a robust regenerative response. Here we show that extracellular periostin induced reentry of differentiated mammalian cardiomyocytes into the cell cycle. Periostin stimulated mononucleated cardiomyocytes to go through the full mitotic cell cycle. Periostin activated alphaV, beta1, beta3 and beta5 integrins located in the cardiomyocyte cell membrane. Activation of phosphatidylinositol-3-OH kinase was required for periostin-induced reentry of cardiomyocytes into the cell cycle and was sufficient for cell-cycle reentry in the absence of periostin. After myocardial infarction, periostin-induced cardiomyocyte cell-cycle reentry and mitosis were associated with improved ventricular remodeling and myocardial function, reduced fibrosis and infarct size, and increased angiogenesis. Thus, periostin and the pathway that it regulates may provide a target for innovative strategies to treat heart failure. 相似文献
73.
74.
Mono-, di-, and trilinoleoyl glycerols were diluted with 1-undecanol or hexadecane to produce specific concentrations, and their oxidation processes were measured at 65 degrees C at 12% relative humidity. The rate constants for oxidation of the linoleoyl residue were proportional to the concentration for all substrates. This fact suggests that no intramolecular radical chain reaction between the linoleoyl residues occurred. 相似文献
75.
Masae Ikura Kanji Furuya Shun Matsuda Ryo Matsuda Hiroki Shima Jun Adachi Tomonari Matsuda Takuma Shiraki Tsuyoshi Ikura 《Molecular and cellular biology》2015,35(24):4147-4157
The association and dissociation of DNA damage response (DDR) factors with damaged chromatin occurs dynamically, which is crucial for the activation of DDR signaling in a spatiotemporal manner. We previously showed that the TIP60 histone acetyltransferase complex acetylates histone H2AX, to facilitate H2AX exchange at sites of DNA damage. However, it remained unclear how the acetylation of histone H2AX by TIP60 is related to the DDR signaling. We found that the acetylation but not the phosphorylation of H2AX is essential for the turnover of NBS1 on damaged chromatin. The loss of H2AX acetylation at Lys 5 by TIP60 in cells disturbed the accumulation of NBS1 at sites of DNA damage. Although the phosphorylation of H2AX is also reportedly required for the retention of NBS1 at damage sites, our data indicated that the acetylation-dependent NBS1 turnover by TIP60 on damaged chromatin restricts the dispersal of NBS1 foci from the sites of DNA damage. These findings indicate the importance of the acetylation-dependent dynamic binding of NBS1 to damaged chromatin, created by histone H2AX exchange, for the proper accumulation of NBS1 at DNA damage sites. 相似文献
76.
77.
Shima Y Ito Y Hatabayashi H Koma A Yabe K 《Bioscience, biotechnology, and biochemistry》2011,75(1):181-184
Five carboxin-resistant mutants from Aspergillus oryzae were characterized by the sensitivities of their mycelial growth and succinate dehydrogenase (SDH) activity to carboxin and three related fungicides. Despite a significant resistance to carboxin, exhibited by all the mutants, their patterns of sensitivity to the other fungicides was distinct. This provides clues to the molecular interaction between SDH and these fungicides. 相似文献
78.
Taniguchi H He M Wu P Kim S Paik R Sugino K Kvitsiani D Kvitsani D Fu Y Lu J Lin Y Miyoshi G Shima Y Fishell G Nelson SB Huang ZJ 《Neuron》2011,71(6):995-1013
A key obstacle to understanding neural circuits in the?cerebral cortex is that of unraveling the diversity of GABAergic interneurons. This diversity poses general questions for neural circuit analysis: how are these interneuron cell types generated and assembled into stereotyped local circuits and how do they differentially contribute to circuit operations that underlie cortical functions ranging from perception to cognition? Using genetic engineering in mice, we have generated and characterized approximately 20 Cre and inducible CreER knockin driver lines that reliably target major classes and lineages of GABAergic neurons. More select populations are captured by intersection of Cre and Flp drivers. Genetic targeting allows reliable identification, monitoring, and manipulation of cortical GABAergic neurons, thereby enabling a systematic and comprehensive analysis from cell fate specification, migration, and connectivity, to their functions in network dynamics and behavior. As such, this approach will accelerate the study of GABAergic circuits throughout the mammalian brain. 相似文献
79.
Watson C Owen DR Harding D Kon-I K Lewis ML Mason HJ Matsumizu M Mukaiyama T Rodriguez-Lens M Shima A Takeuchi M Tran I Young T 《Bioorganic & medicinal chemistry letters》2011,21(14):4284-4287
A series of benzimidazole CB2 receptor agonists were prepared and their properties investigated. Optimisation of the three benzimidazole substituents led to the identification of compound 23, a potent CB2 full agonist (EC50 2.7 nM) with excellent selectivity over the CB1 receptor (>3000-fold). Compound 23 demonstrated good CNS penetration in rat. Further optimisation led to the identification of compound 34 with improved selectivity over hERG and excellent CNS penetration in rat. 相似文献
80.
Homocysteine thiolactone (HCTL) is a cyclic thioester of homocysteine, showing high reactivity toward lysine residues of proteins.
In the present study the structural properties and aggregation propensity of bovine pancreatic insulin were studied in the
presences of increasing concentration of HCTL (0–500 μM), using different spectroscopic techniques. As shown in this study,
HCTL induces gross structural alterations and subsequently aggregation of insulin in a dose dependent manner. Also induction
of insulin aggregation by HCTL occurs in a sequential process, where native protein with alpha-helical abundant structure
gradually transforms into partially folded conformations with the significant amount of beta-sheet. Since C-terminal B-chain
of insulin plays a critical role in stability of this protein, the structural alteration/aggregation induced by HCTL can be
consequence of homocysteinylation of the only Lysine residue (Lys29) on its B-chain. This study may have important implications
regarding the effect of HCTL on structure of insulin particularly in the pathological states linked to hyperhomocysteinemia. 相似文献