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911.
The regulatory role of calmodulin-dependent guanylate cyclase in association with hormonal imprinting in Tetrahymena 总被引:1,自引:0,他引:1
The primary interaction with insulin accounted for considerable increases in both the calmodulin content and guanylate cyclase activity of Tetrahymena. Both activities were still elevated after 24 h (6-8 generations), but while the calmodulin level showed a decrease, guanylate cyclase activity showed a further significant increase relative to the immediate response. A second treatment with insulin decreased rather than increased both activities, but to dissimilar degrees, in that the calmodulin content returned to the control level, whereas guanylate cyclase activity still increased over the level measured after the first treatment. It appears that insulin imprinting altered the calmodulin-dependent guanylate cyclase regulation in Tetrahymena, and caused a switch-over to an 'energy-saving' system through decelerating the breakdown of cGMP by phosphodiesterase. 相似文献
912.
913.
Yuyo Ka Tomoyuki Ogura Kayo Tomiyama Masami Ueno Ryoko Nozu Nobuyuki Tsuruzono Yuya Nozawa Mariko Hamano Akira Takakura Riichi Takahashi 《Experimental Animals》2021,70(2):177
To avoid microbial contamination risk, vinyl film isolators are generally used in animal microbiome experiments involving germ-free (GF) mice and/or gnotobiotic (GB) mice. However, it can take several months to gain expertise in operating the isolator competently. Furthermore, sterilization and sterility testing, which are essential for isolator preparation, can take more than 20 days. Hence, we built an experimental rearing environment that combines an individual ventilation cage system and a bioBUBBLE clean room enclosure to easily set up an experimental animal microbiome environment for animal facilities. In this work, a three-step evaluation was conducted. First, we examined whether GF mice can be maintained in this rearing environment without bacterial contamination. Next, we examined whether GF and GB mice can be maintained without cross-contamination in one individual ventilation cage rack. Finally, we tested whether GF mice can be maintained in a biological safety cabinet controlled by negative pressure. In our series of experiments, no microbial contamination occurred over more than 3 months. These results indicated that our rearing system that combines the individual ventilation cage and bioBUBBLE systems can be used not only for experiments with GF mice but also for Biosafety Level 2 experiments that handle bacteria. Our system can mitigate various disadvantages of using vinyl film isolators. In conclusion, we established an experimental method with improved working time and efficiency compared with those of the previous vinyl isolator method. 相似文献
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918.
A. Kume Naoko Tsuboi Takami Satomura Masayo Suzuki Masaaki Chiwa Kaneyuki Nakane Naoki Sakurai Takao Horikoshi Hiroshi Sakugawa 《Trees - Structure and Function》2000,14(6):305-311
The decline of Japanese red pine trees (Pinus densiflora Sieb. et Zucc.) at Mt. Gokurakuji (693 m a.s.l.), 30 km west of Hiroshima city, west Japan, was studied. The effects of air
pollution and acid deposition on the physiological characteristics of the trees, especially those of the needles, were investigated.
Ozone concentration was not correlated with the physiological status of the needles and SO2 concentration was not high in the declined area. NO2 concentration correlated negatively with needle longevity while it correlated positively with ethylene emission from 1-year-old
needles. Average needle longevity was about 2.8 years in non-declined areas; however the longevity was 1.3 years in the most
polluted area. The minimal fluorescence at night (F
0)of 1-year-old needles decreased with increasing NO2 concentration. The maximum stomatal conductance (gl), net photosynthesis (P
n)and intercellular CO2 concentration (C
i) in the declined areas were lower than in the non- declined areas (about 50%, 30% and 20% lower, respectively). The lower
C
isuggested that the major part of the decrease in P
ncan be explained by stomatal restriction. The soil pH, N content and C/N ratio showed no significant difference between the
declined and non-declined areas. The physiological disorders of needles were due to the damage by air pollutants, and important
roles of NO2 are suggested. Lowering of P
n and the shortening of needle longevity appear to be the main causes of the decline in pines in the forest decline area.
Received: 16 December 1998 / Accepted: 7 January 2000 相似文献
919.
K Kawai Y Nozawa Y Maebayashi M Yamazaki T Hamasaki 《Applied and environmental microbiology》1984,47(3):481-483
Averufin and averufin dimethylether from Aspergillus versicolor were examined for their uncoupling effects on oxidative phosphorylation in isolated rat liver mitochondria to get insight into the mode of toxic action of averufin. Averufin uncoupled oxidative phosphorylation, causing 50% uncoupling at about 1.5 microM with respect to the decrease in P/O ratio. Averufin dimethylether did not uncouple but inhibited state 3 respiration of mitochondria, which was not released by either 2,4-dinitrophenol or averufin. 相似文献
920.
Yunpeng Shen Masayo Morishita Doohyun Lee Shinae Kim Taeho Lee Damiaan E.H.F. Mevius Yeonjeong Roh Eric di Luccio 《Biochemical and biophysical research communications》2019,508(1):102-108
The NSD family (NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1) are histone lysine methyltransferases (HMTases) essential for chromatin regulation. The NSDs are oncoproteins, drivers of a number of tumors and are considered important drug-targets but the lack of potent and selective inhibitors hampers further therapeutic development and limits exploration of their biology. In particular, MMSET/NSD2 selective inhibition is being pursued for therapeutic interventions against multiple myeloma (MM) cases, especially in multiple myeloma t(4;14)(p16.3;q32) translocation that is associated with a significantly worse prognosis than other MM subgroups. Multiple myeloma is the second most common hematological malignancy, after non-Hodgkin lymphoma and remains an incurable malignancy.Here we report the discovery of LEM-14, an NSD2 specific inhibitor with an in vitro IC50 of 132?μM and that is inactive against the closely related NSD1 and NSD3. LEM-14-1189, a LEM-14 derivative, differentially inhibits the NSDs with in vitro IC50 of 418?μM (NSD1), IC50 of 111?μM (NSD2) and IC50 of 60?μM (NSD3). We propose LEM-14 and derivative LEM-14-1189 as tools for studying the biology of the NSDs and constitute meaningful steps toward potent NSDs therapeutic inhibitors. 相似文献