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1.
Shunsuke Yaguchi Atsuko Yamazaki Wakana Wada Yasutaka Tsuchiya Toshihiko Sato Hideo Shinagawa Yutaro Yamada Junko Yaguchi 《Development, growth & differentiation》2015,57(3):242-250
Sea urchins are model non‐chordate deuterostomes, and studying the nervous system of their embryos can aid in the understanding of the universal mechanisms of neurogenesis. However, despite the long history of sea urchin embryology research, the molecular mechanisms of their neurogenesis have not been well investigated, in part because neurons appear relatively late during embryogenesis. In this study, we used the species Temnopleurus reevesii as a new sea urchin model and investigated the detail of its development and neurogenesis during early embryogenesis. We found that the embryos of T. reevesii were tolerant of high temperatures and could be cultured successfully at 15–30°C during early embryogenesis. At 30°C, the embryos developed rapidly enough that the neurons appeared at just after 24 h. This is faster than the development of other model urchins, such as Hemicentrotus pulcherrimus or Strongylocentrotus purpuratus. In addition, the body of the embryo was highly transparent, allowing the details of the neural network to be easily captured by ordinary epifluorescent and confocal microscopy without any additional treatments. Because of its rapid development and high transparency during embryogenesis, T. reevesii may be a suitable sea urchin model for studying neurogenesis. Moreover, the males and females are easily distinguishable, and the style of early cleavages is intriguingly unusual, suggesting that this sea urchin might be a good candidate for addressing not only neurology but also cell and developmental biology. 相似文献
2.
《Bioorganic & medicinal chemistry letters》2014,24(3):949-953
We designed and synthesized a novel series of phenylamino- and phenoxy-substituted pyrazolo[3,4-d]pyrimidine derivatives as GPR119 agonists. SAR studies indicated that electron-withdrawing substituents on the phenyl ring are important for potency and full efficacy. Compound 26 combined good potency with a promising pharmacokinetic profile in mice, and lowered the glucose excursion in mice in an oral glucose-tolerance test. 相似文献
3.
Luis Santamaría Jesús Balsa Beatriz Bidondo Angel Baltanás Carlos Montes 《Hydrobiologia》1992,246(2):89-98
Laboratory experiments and field data were used to determine salinity tolerance limits of three ostracode species (Prionocypris aragonica, Eucypris mareotica and Heterocypris barbara) from Iberian saline lakes. Salinity tolerance appeared related to ionic composition and temperature. Implications for ostracode ecology and geographical distribution are evaluated. 相似文献
4.
Glyceraldehyde-3-phosphate dehydrogenase from Thermotoga maritima: Strategies of protein stabilization 总被引:2,自引:0,他引:2
Rainer Jaenicke 《FEMS microbiology reviews》1996,18(2-3):215-224
Abstract: The molecular origin of protein stability has been the subject of active research for more than a generation (R. Jaenicke (1991) Eur. J. Biochem. 202, 715–728). Faced with the discovery of extremophiles, in recent years the problem has gained momentum, especially because of its biotechnological potential. In analyzing a number of enzymes from the hyperthermophilic bacterium Thermotoga maritima , it has become clear that the excess free energy of stabilization is equivalent to only a few weak bonds ( ΔΔG stab ≈ 50 kJ/mol). As taken from the comparison of homologous enzymes from mesophiles, thermophiles and hyperthermophiles, these accumulate from local interactions (especially ion pairs), enhanced secondary or supersecondary structure, and improved packing of domains and/or subunits, without significantly altering the overall topology. In this review, glyceraldehyde-3-phosphate dehydrogenase will be discussed as a representative example to illustrate possible adaptive strategies to the extreme thermal stress in hydrothermal vents. 相似文献
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Wensheng Shen § Fuqian Yang ∥ 《Computer methods in biomechanics and biomedical engineering》2013,16(2):115-125
A three-dimensional (3D) multilayer model based on the skin physical structure is developed to investigate the transient thermal response of human skin subject to laser heating. The temperature distribution of the skin is modeled by the bioheat transfer equation, and the influence of laser heating is expressed as a source term where the strength of the source is a product of a Gaussian shaped incident irradiance, an exponentially shaped axial attenuation, and a time function. The water evaporation and diffusion is included in the model by adding two terms regarding the heat loss due to the evaporation and diffusion, where the rate of water evaporation is determined based on the theory of laminar boundary layer. Cryogen spray cooling (CSC) in laser therapy is studied, as well as its effect on the skin thermal response. The time-dependent equation is discretized using the finite difference method with the Crank–Nicholson scheme and the stability of the numerical method is analyzed. The large sparse linear system resulted from discretizing the governing partial differential equation is solved by a GMRES solver and the expected simulation results are obtained. 相似文献
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Two Saccharomyces cerevisiae strains with different degrees of ethanol tolerance adapted differently to produced ethanol. Adaptation in the less ethanol-tolerant
strain was high and resulted in a reduced formation of ethanol-induced respiratory deficient mutants and an increased ergosterol
content of the cells. Adaptation in the more ethanol-tolerant strain was less pronounced. Journal of Industrial Microbiology & Biotechnology (2000) 24, 75–78.
Received 22 June 1999/ Accepted in revised form 06 October 1999 相似文献
10.
SALT TOLERANCE IN THE HALOPHYTE SUAEDA MARITIMA (L.) DUM. 总被引:1,自引:0,他引:1