http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Tsuyama, Takashi,Watanabe, Saori,Aoki, Ayako,Cho, Yunje,Seki, Masayuki,Enomoto, Takemi,Tada, Shusuke American Society for Cell Biology 2009 Molecular biology of the cell Vol.20 No.3
<P>Excess Cdt1 reportedly induces rereplication of chromatin in cultured cells and Xenopus egg extracts, suggesting that the regulation of Cdt1 activity by cell cycle-dependent proteolysis and expression of the Cdt1 inhibitor geminin is crucial for the inhibition of chromosomal overreplication between S phase and metaphase. We analyzed the consequences of excess Cdt1 for DNA replication and found that increased Cdt1 activity inhibited the elongation of nascent strands in Xenopus egg extracts. In Cdt1-supplemented extracts, overreplication was remarkably induced by the further addition of the Cdt1-binding domain of geminin (Gem79-130), which lacks licensing inhibitor activity. Further analyses indicated that fully active geminin, as well as Gem79-130, restored nascent strand elongation in Cdt1-supplemented extracts even after the Cdt1-induced stalling of replication fork elongation had been established. Our results demonstrate an unforeseen, negative role for Cdt1 in elongation and suggest that its function in the control of replication should be redefined. We propose a novel surveillance mechanism in which Cdt1 blocks nascent chain elongation after detecting illegitimate activation of the licensing system.</P>
Atsushi Shirai,Takuya Suzuki,Takashi Seki 한국한의학연구원 2015 Integrative Medicine Research Vol.4 No.3
Background: The aim of this study was to develop a mathematical model of blood flow in the systemic circulation to emulate the change in hemodynamics by acupuncture therapy to elucidate the mechanism of the therapy. For this purpose, as a first step, a simple model of arterial blood flow was presented to reproduce previously reported change in the blood flow volume by the acupuncture needle stimulation of Taichong (LR-3). Methods: This model was based on the lumped-parameter approximation of arterial blood flow together with linear resistance of peripheral circulation. It has been reported that blood flow in the left arm was enhanced after the stimulation, yielding the peripheral vascular resistance-regulated blood flow dominated by the sympathetic nervous system. In addition to the peripheral resistance, another parameter that possibly regulates the blood flow is the cross-sectional area of the vessel. These two factors were changed to numerically examine their contributions to the blood flow based on the hypothesis that they could be changed by the stimulation. The numerical result was compared with the experimental result to confirm the validity of the hypothesis that the blood flow in the arm is regulated by the peripheral resistance. Results: This model is extremely simple and the physical parameters introduced for the simulation were gleaned from different reports in the literature. It was demonstrated, however, that regulation of the peripheral resistance rather than of the cross-sectional area could reproduce the experimentally observed change in the blood flow. Moreover, the relationship between the changes in the flow volume and the systemic vascular resistance quantitatively matched the experimental data. Conclusion: The present model has a potential to emulate hemodynamic change by acupuncture therapy by incorporating physiological correlation of stimulation of an acupoint and regulation of parameters that affect the hemodynamics.
Lee, Eun-Hye,Kamigaito, Yoshiki,Tsujimoto, Takashi,Seki, Shu,Uyama, Hiroshi,Tagawa, Seiichi,Sung, Moon-Hee The Society of Fiber Science and Technology, Japan 2010 纖維學會誌 Vol.66 No.4
<P>Poly(γ-glutamic acid) (PGA) was crosslinked by γ-ray irradiation to produce the transparent PGA hydrogel. The effects of the molecular weight of PGA and the dosage of the γ-ray irradiation on the swelling ability and mechanical strength of the PGA hydrogel were systematically investigated. The preparation of PGA hydrogel / apatite composite was performed by soaking the hydrogel in a simulated body fluid. The hydrogel obtained from the calcium form of PGA became turbid during the soaking to form the PGA composite. The FT-IR and XRD analyses showed the formation of the crystalline apatite in the PGA hydrogel. The surface morphology of the composite was observed by SEM. Proliferation of MC3T3-E1 cells on the resulting composite was examined for application of tissue engineering scaffold.</P>