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151.
Cyclic tetra‐β‐peptides (CP4s) and a bis‐CP4 were synthesized to prepare peptide nanotubes (PNTs) by molecular stacking of cyclic peptides. The addition of bis‐CP4 to the PNT preparation afforded PNT bundles increasing the direct and converse piezoelectiric coefficients, which is ascribable to bis‐CP4 stapling PNTs into the parallel alignment of PNT dipoles. 相似文献
152.
Sebastián Acosta-Jurado Dulce-Nombre Rodríguez-Navarro Yasuyuki Kawaharada Miguel A. Rodríguez-Carvajal Antonio Gil-Serrano María E. Soria-Díaz Francisco Pérez-Montaño Juan Fernández-Perea Yanbo Niu Cynthia Alias-Villegas Irene Jiménez-Guerrero Pilar Navarro-Gómez Francisco Javier López-Baena Simon Kelly Niels Sandal Jens Stougaard José E. Ruiz-Sainz José-María Vinardell 《Environmental microbiology》2019,21(5):1718-1739
153.
Kadomura K Naruse S Sugihara S Yamaguchi K Oda T 《Bioscience, biotechnology, and biochemistry》2007,71(8):2029-2033
Previous studies have indicated that the devil stinger produces reactive oxygen species (ROS) during early development from fertilized egg to larva. To determine whether ROS generation is a common feature in marine fish species, we conducted chemiluminescence analysis using ROS specific probe (L012) on larvae of six marine fish species. Marbled rockfish, black rockfish, and devil stinger showed higher levels of chemiluminescence response (CR), whereas the levels of CR of sevenband grouper, tiger puffer, and red seabream were fairly lower. These CRs were inhibited by the addition of superoxide dismutase. Hypersensitive photon-counting microscopic observation of black rockfish suggested that ROS production was concentrated in the head area. Our results suggest that the larvae of these six marine fishes produce ROS to considerably different extents depending on species, and that rockfish species, belonging to ovoviviparous fish, tend to produce much higher levels of ROS especially at the later larval stage. 相似文献
154.
Biofilm Formation and Dispersal under the Influence of the Global Regulator CsrA of Escherichia coli
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Debra W. Jackson Kazushi Suzuki Lawrence Oakford Jerry W. Simecka Mark E. Hart Tony Romeo 《Journal of bacteriology》2002,184(1):290-301
The predominant mode of growth of bacteria in the environment is within sessile, matrix-enclosed communities known as biofilms. Biofilms often complicate chronic and difficult-to-treat infections by protecting bacteria from the immune system, decreasing antibiotic efficacy, and dispersing planktonic cells to distant body sites. While the biology of bacterial biofilms has become a major focus of microbial research, the regulatory mechanisms of biofilm development remain poorly defined and those of dispersal are unknown. Here we establish that the RNA binding global regulatory protein CsrA (carbon storage regulator) of Escherichia coli K-12 serves as both a repressor of biofilm formation and an activator of biofilm dispersal under a variety of culture conditions. Ectopic expression of the E. coli K-12 csrA gene repressed biofilm formation by related bacterial pathogens. A csrA knockout mutation enhanced biofilm formation in E. coli strains that were defective for extracellular, surface, or regulatory factors previously implicated in biofilm formation. In contrast, this csrA mutation did not affect biofilm formation by a glgA (glycogen synthase) knockout mutant. Complementation studies with glg genes provided further genetic evidence that the effects of CsrA on biofilm formation are mediated largely through the regulation of intracellular glycogen biosynthesis and catabolism. Finally, the expression of a chromosomally encoded csrA'-'lacZ translational fusion was dynamically regulated during biofilm formation in a pattern consistent with its role as a repressor. We propose that global regulation of central carbon flux by CsrA is an extremely important feature of E. coli biofilm development. 相似文献
155.
Flow of photosynthesized carbon from rice plants into the paddy soil ecosystem at different stages of rice growth 总被引:1,自引:0,他引:1
Watanabe Akira Machida Nobuhisa Takahashi Kazushi Kitamura Shigeru Kimura Makoto 《Plant and Soil》2004,258(1):151-160
To elucidate the flow of C assimilated by rice plants into soil C, soil biomass C, and emitted CH4 at different rice growth stages, 13C pulse-labeling was conducted at the maximum-tiller-number (first experiment), booting (second experiment), and milky stages (third experiment) for potted rice grown outdoors under flooded conditions. The distribution of the assimilated C into each fraction was traced during a 14-day period. The atom-13C% excess of shoots was the highest just after the 6 h feeding of 13CO2 and decreased until days 14, 7, and 3 in the first, second, and third experiments, respectively. Translocation of the assimilated C into roots was largest in the first experiment, 13%, while that into ears was more than 50% in the third experiment. The proportion of the rice-assimilated C recovered in soil organic matter increased with time after labeling and reached 3.4%, 3.0%, and 1.7% on day 14 in the first, second, and third experiments, respectively. Incorporation of the rice-assimilated C was faster into soil microbial biomass than into gross soil organic matter or the 0.5 M K2SO4-extractable fraction. Although the percent of labeled soil C that is in the microbial biomass on day 0 was much larger at the maximum-tiller-number stage (42%) than at the milky stage (5%), its variation among growth stages was small on day 14 (10 to 15%). The percent of the rice-assimilated C emitted as CH4 during the 14-day period at the maximum-tiller-number, booting, and milky stages was 0.003%, 0.26%, and 0.30%, respectively. 相似文献
156.
Elizabeth A. Fry Pankaj Taneja Dejan Maglic Sinan Zhu Guangchao Sui Kazushi Inoue 《PloS one》2013,8(10)
Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG) under the control of the mouse mammary tumor virus (MMTV) promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21Cip1, markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression. 相似文献
157.
158.
Kentaro Honda Takaomi Arai Nobuyuki Takahashi Kazushi Miyashita 《Ichthyological Research》2010,57(4):416-421
Microchemical analysis of the strontium (Sr) and calcium (Ca) ratios of otoliths was conducted to determine the life history
and migration of anadromous Sakhalin taimen, Hucho perryi. In 2008 and 2009, 10 specimens were sampled from Lake Akkeshi in eastern Hokkaido, Japan. Our results indicated that some
specimens migrated to brackish waters during their early life histories. Because the Sr:Ca ratios of the specimens in this
study were all less than those of specimens from Sakhalin Island during a previous study, specimens from Lake Akkeshi may
have migrated to brackish water, or may have remained in the ocean for only a short period. 相似文献
159.
Kazushi Tamura Takeomi Mizutani Hisashi Haga Kazushige Kawabata 《Histochemistry and cell biology》2010,133(1):59-67
In this study, we aimed at improving the temporal resolution of scanning probe microscopy (SPM) for observing living cells
by introducing soft cantilevers, low feedback-gain operations, and cantilever deflection imaging. We achieved visualization
of the mechanical architecture in leading lamellae of living fibroblasts at a temporal resolution of around 10 s, which is
higher than that of conventional contact-mode SPM. Time-lapse SPM could be used to monitor not only cytoskeletal dynamics
but also the dynamics of numerous microgranules. Statistical analysis of microgranular motion revealed that the microgranules
have superdiffusive behaviors and significant directional order of motion. We also found that the direction of their motion
is correlated with the direction of growing actin stress fibers. The combination of SPM with fluorescence microscopy showed
that vinculin, a component of cell-substratum adhesion sites, localizes at the microgranules. Our experimental data provides
a new insight into the intracellular mechanical architecture and its structural dynamics, suggesting that high-speed live-cell
SPM has great potential for investigating the structural origin of cellular dynamics. 相似文献
160.
Akihiro Furukawa Tsuyoshi Arita Susumu Satoh Kenji Wakabayashi Shinko Hayashi Yumi Matsui Kazushi Araki Masanori Kuroha Jun Ohsumi 《Bioorganic & medicinal chemistry letters》2010,20(7):2095-2098
In an investigation of (?)-Cercosporamide derivatives with a plasma glucose-lowering effect, we found that N-benzylcarboxamide derivative 4 was a partial agonist of PPARγ. A SAR study of the substituents on carboxamide nitrogen afforded the N-(1-naphthyl)methylcarboxamide derivative 23 as the most potent selective PPARγ modulator. An X-ray crystallography study revealed that compound 23 bounded to the PPARγ ligand binding domain in a unique way without any interaction with helix12. Compound 23 displayed a potent plasma glucose-lowering effect in db/db mice without the undesirable increase in body fluid and heart weight that is typically observed when PPARγ full agonists are administrated. 相似文献