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91.
Understanding how defects in mechanotransduction affect cell‐to‐cell variability will add to the fundamental knowledge of human pluripotent stem cell (hPSC) culture, and may suggest new approaches for achieving a robust, reproducible, and scalable process that result in consistent product quality and yields. Here, the current state of the understanding of the fundamental mechanisms that govern the growth kinetics of hPSCs between static and dynamic cultures is reviewed, the factors causing fluctuations are identified, and culture strategies that might eliminate or minimize the occurrence of cell‐to‐cell variability arising from these fluctuations are discussed. The existing challenges in the development of hPSC expansion methods for enabling the transition from process development to large‐scale production are addressed, a mandatory step for industrial and clinical applications of hPSCs. 相似文献
92.
Bo Zhang Akira Matsunaga David L. Rainwater Shin-ichiro Miura Keita Noda Hiroaki Nishikawa Yoshinari Uehara Kazuyuki Shirai Masahiro Ogawa Keijiro Saku 《Journal of lipid research》2009,50(9):1832-1841
Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP. 相似文献
93.
H. Aoshima D.J. Cash G.P. Hess 《Biochemical and biophysical research communications》1980,92(3):896-904
The dependence of acetylcholine receptor-controlled transmembrane ion flux on carbamylcholine concentration was measured in the msec time region, using membrane vesicles and a quench flow technique. 4 Measurements were made: (1) transmembrane ion influx, (2) rate of inactivation of the receptor by carbamylcholine, (3) rate of recovery, and (4) ion influx mediated by “inactivated” receptor. The minimal model, based on the measurements, accounts for the time dependence of receptor-controlled ion flux over a 200-fold carbamylcholine concentration range. The maximum flux rate of 84 sec?1 indicates that we have succeeded in measuring the receptor-controlled processes which give rise to electrical signals in cells. 相似文献
94.
Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
95.
Furihata Ryuji Kizuki Jun Yamano Yuya Mizoguchi Yasuhide Nakajima Suguru Nagai Kou Kaneko Yoshiyuki Yamada Koju Suzuki Masahiro Uchiyama Makoto 《Sleep and biological rhythms》2020,18(2):155-157
Sleep and Biological Rhythms - A 39-year-old married woman was referred to a psychiatry outpatient clinic for treatment of major depressive disorder (MDD). The dose of zolpidem she had been taking... 相似文献
96.
Ionic liquids (ILs), a class of materials with unique physicochemical properties, have been used extensively in the fields of chemical engineering, biotechnology, material sciences, pharmaceutics, and many others. Because ILs are very polar by nature, they can migrate into the environment with the possibility of inclusion in the food chain and bioaccumulation in living organisms. However, the chemical natures of ILs are not quintessentially biocompatible. Therefore, the practical uses of ILs must be preceded by suitable toxicological assessments. Among different methods, the use of microorganisms to evaluate IL toxicity provides many advantages including short generation time, rapid growth, and environmental and industrial relevance. This article reviews the recent research progress on the toxicological properties of ILs toward microorganisms and highlights the computational prediction of various toxicity models. 相似文献
97.
98.
Tokimatsu Koji Tang Longlong Yasuoka Rieko Ii Ryota Itsubo Norihiro Nishio Masahiro 《The International Journal of Life Cycle Assessment》2020,25(9):1710-1736
The International Journal of Life Cycle Assessment - Despite the long-standing demand for research on dynamic lifecycle assessment (LCA) for policymaking, only a few studies have addressed this... 相似文献
99.
Marcin Nowicki Logan C. Houston Sarah L. Boggess Anthony S. Aiello Miriam Pay‐Milans Margaret E. Staton Mitsuhiro Hayashida Masahiro Yamanaka Shigetoshi Eda Robert N. Trigiano 《Ecology and evolution》2020,10(15):8299-8312
Cornus kousa (Asian dogwood), an East Asia native tree, is the most economically important species of the dogwood genus, owing to its desirable horticultural traits and ability to hybridize with North America‐native dogwoods. To assess the species genetic diversity and to better inform the ongoing and future breeding efforts, we assembled an herbarium and arboretum collection of 131 noncultivated C. kousa specimens. Genotyping and capillary electrophoresis analyses of our C. kousa collection with the newly developed genic and published nuclear genomic microsatellites permitted assessment of genetic diversity and evolutionary history of the species. Regardless of the microsatellite type used, the study yielded generally similar insights into the C. kousa diversity with subtle differences deriving from and underlining the marker used. The accrued evidence pointed to the species distinct genetic pools related to the plant country of origin. This can be helpful in the development of the commercial cultivars for this important ornamental crop with increased pyramided utility traits. Analyses of the C. kousa evolutionary history using the accrued genotyping datasets pointed to an unsampled ancestor population, possibly now extinct, as per the phylogeography of the region. To our knowledge, there are few studies utilizing the same gDNA collection to compare performance of genomic and genic microsatellites. This is the first detailed report on C. kousa species diversity and evolutionary history inference. 相似文献
100.
Shoko Nakano Yuko Abe Kimiko Nakajima Shigetoshi Sano Osamu Yamamoto Kazumasa Wakamatsu Shosuke Ito Masahiro Hayashi Tamio Suzuki 《Pigment cell & melanoma research》2021,34(1):101-110
Post‐inflammatory hyperpigmentation (PIH) is a common cutaneous condition that can cause a disfigured appearance. However, the pathophysiology of PIH remains poorly understood, at least in part, because an appropriate animal model for research has not been established. In order to analyze the pathomechanism of PIH, we successfully induced PIH in a hairless version of transgenic mice (hk14‐SCF Tg/HRM) that have a human‐type epidermis containing melanin by repeated hapten application of 2,4‐dinitrofluorobenzene. Histopathologic observation showed epidermal hyperplasia, predominant infiltrations of inflammatory cells, and melanin‐containing cells in the dermis just after elicitation of the atopic dermatitis‐like condition. At week 2, the findings were similar to the characteristics of PIH, that is, an increase of melanin without spongiosis or liquid degeneration in the epidermis and an increase in dermal melanophages. Dynamic analysis of melanin showed that the melanin in the dermis remained for a longer duration than in the epidermis. Furthermore, immunohistochemical staining revealed that the majority of cells containing melanin were positive for the anti‐CD68 antibody, but negative for the anti‐F4/80 antibody. These data suggest that novel treatments of PIH should be targeted against macrophages and should eventually lead to the development of new treatment modalities. 相似文献