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81.
Thi Hai Yen Tran Aya Fukuda Shiho Aizawa Phuong Linh Bui Yohei Hayashi Ken Nishimura Koji Hisatake 《Biochemistry and Biophysics Reports》2018
Generation of induced pluripotent stem cells (iPSCs) with naive pluripotency is important for their applications in regenerative medicine. In female iPSCs, acquisition of naive pluripotency is coupled to X chromosome reactivation (XCR) during somatic cell reprogramming, and live cell monitoring of XCR is potentially useful for analyzing how iPSCs acquire naive pluripotency. Here we generated female mouse embryonic stem cells (ESCs) that carry the enhanced green fluorescent protein (EGFP) and humanized Kusabira-Orange (hKO) genes inserted into an intergenic site near either the Syap1 or Taf1 gene on both X chromosomes. The ESC clones, which initially expressed both EGFP and hKO, inactivated one of the fluorescent protein genes upon differentiation, indicating that the EGFP and hKO genes are subject to X chromosome inactivation (XCI). When the derived somatic cells carrying the EGFP gene on the inactive X chromosome (Xi) were reprogrammed into iPSCs, the EGFP gene on the Xi was reactivated when pluripotency marker genes were induced. Thus, the fluorescent protein genes inserted into an intergenic locus on both X chromosomes enable live cell monitoring of XCI during ESC differentiation and XCR during reprogramming. This is the first study that succeeded live cell imaging of XCR during reprogramming. 相似文献
82.
Tadashi Gomi 《Oecologia》1997,111(2):160-165
The fall webworm, Hyphantria cunea Drury (Lepidoptera: Arctiidae), was introduced from North America to Japan half a century ago. The critical photoperiod for
diapause induction and its temperature dependence, as defined by the difference in the critical photoperiod between 20 and
25°C, were investigated in order to understand the mechanisms behind a shift from bi- to trivoltine life cycles. The critical
photoperiod for diapause induction was shorter in the southern trivoltine populations than in the northern bivoltine populations,
and this was more marked at 25°C than at 20°C. Although the critical photoperiod showed a positive correlation with the original
latitude, the correlation was relatively low at both temperatures. Conversely, temperature dependence of the critical photoperiod
for diapause induction correlated negatively with the original latitude. The trivoltine populations showed greater temperature
sensitivity than the bivoltine populations. These results suggest that an increase in temperature sensitivity of the diapause
response to photoperiods was involved in the shift to a trivoltine life cycle. The crossing experiments suggested that the
photoperiodic control of diapause induction and its temperature dependence are under polygenic control without sex-linkage.
Received: 29 October 1996 / Accepted: 26 February 1997 相似文献
83.
Characterization of Fusarium oxysporum β-1,6-Galactanase, an Enzyme That Hydrolyzes Larch Wood Arabinogalactan 下载免费PDF全文
Tatsuji Sakamoto Yuya Taniguchi Shiho Suzuki Hideshi Ihara Haruhiko Kawasaki 《Applied microbiology》2007,73(9):3109-3112
A type II arabinogalactan-degrading enzyme (FoGal1) was purified from Fusarium oxysporum 12S, and the corresponding cDNA was isolated. FoGal1 had high similarity to enzymes of glycoside hydrolase family 5. Treatment of larch wood arabinogalactan with the recombinant enzyme indicated that FoGal1 is a β-1,6-galactanase that preferentially debranches β-1,6-galactobiose from the substrate. 相似文献
84.
Koji Kashima Yoshikazu Yuki Mio Mejima Shiho Kurokawa Yuji Suzuki Satomi Minakawa Natsumi Takeyama Yoshiko Fukuyama Tatsuhiko Azegami Takeshi Tanimoto Masaharu Kuroda Minoru Tamura Yasuyuki Gomi Hiroshi Kiyono 《Plant cell reports》2016,35(3):667-679
Key message
The first Good Manufacturing Practices production of a purification-free rice-based oral cholera vaccine (MucoRice-CTB) from transgenic plants in a closed cultivation system yielded a product meeting regulatory requirements.Abstract
Despite our knowledge of their advantages, plant-based vaccines remain unavailable for human use in both developing and industrialized countries. A leading, practical obstacle to their widespread use is producing plant-based vaccines that meet governmental regulatory requirements. Here, we report the first production according to current Good Manufacturing Practices of a rice-based vaccine, the cholera vaccine MucoRice-CTB, at an academic institution. To this end, we established specifications and methods for the master seed bank (MSB) of MucoRice-CTB, which was previously generated as a selection-marker-free line, evaluated its propagation, and given that the stored seeds must be renewed periodically. The production of MucoRice-CTB incorporated a closed hydroponic system for cultivating the transgenic plants, to minimize variations in expression and quality during vaccine manufacture. This type of molecular farming factory can be operated year-round, generating three harvests annually, and is cost- and production-effective. Rice was polished to a ratio of 95 % and then powdered to produce the MucoRice-CTB drug substance, and the identity, potency, and safety of the MucoRice-CTB product met pre-established release requirements. The formulation of MucoRice-CTB made by fine-powdering of drug substance and packaged in an aluminum pouch is being evaluated in a physician-initiated phase I study.85.
Obata M Hirohara S Sharyo K Alitomo H Kajiwara K Ogata S Tanihara M Ohtsuki C Yano S 《Biochimica et biophysica acta》2007,1770(8):1204-1211
86.
Tetsuya Yabutani Mami Tsujimoto Shunsuke Ohira Shiho Shimizu Hideo Nakano 《Bioscience, biotechnology, and biochemistry》2017,81(7):1456-1459
A Gram-positive bacterium Lentzea sp. 7887 hydroxylates a cyclosporine derivative FR901459 into AS1837812 (9-hydroxide), which is an important intermediate of candidate drugs that target the hepatitis C virus. We screened a UV-induced mutant, named M-1, which showed about 1.2-fold higher conversion yields, 2-fold higher substrate concentrations (3.69 mM), and 2.5-fold higher yield per unit volume than the wild-type strain. 相似文献
87.
Given the reported degraded nature of DOC in the Rio Negro, and low oxygen, pH, and bacterial riverine levels, we hypothesized: (1) DOC would have strong humic and fulvic acid fluorescence signals with high aromaticity and large mean molecular weight; and (2) photo-oxidation rates would be slow, and reactive oxygen species (ROS) concentrations low, producing no oxidative stress in biota. We surveyed the environment and properties of DOC and explored DOC photo-oxidation and fish sensitivity to DOC products. DOC properties were investigated using absorption and fluorescence indices and parallel factor analysis (PARAFAC) of excitation–emission matrices. ROS concentrations were measured spectrophotometrically. A native fish, Hemigrammus levis, was exposed to photo-oxidizing DOC and its tissues (brain, gill, liver) assayed for changes in antioxidant and biotransformation enzymes. With respect to our hypotheses, (1) DOC was highly terrigenous, with high SAC340 values (aromaticity), high capacity to produce ROS, and high tryptophan-like fluorescence (bacterial, autochthonous signal); (2) photo-oxidation rates were appreciable, while products were related to mean UV-radiation levels (total radiation was constant). ROS levels were often higher than freshwater averages, yet fish experienced no oxidative stress. Results suggest photo-oxidation influences patterns in C-cycling, bacterial production and community dynamics between wet and dry seasons. 相似文献
88.
89.
90.
Nagaaki Sato Makoto Jitsuoka Shiho Ishikawa Keita Nagai Hiroyasu Tsuge Makoto Ando Osamu Okamoto Hisashi Iwaasa Akira Gomori Akane Ishihara Akio Kanatani Takehiro Fukami 《Bioorganic & medicinal chemistry letters》2009,19(6):1670-1674
Novel imidazoline derivatives were discovered to be potent neuropeptide Y Y5 receptor antagonists. High-throughput screening of Merck sample collections against the human Y5 receptor resulted in the identification of 2,4,4-triphenylimidazoline (1), which had an IC50 of 54 nM. Subsequent optimization led to the identification of several potent derivatives. 相似文献