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81.
Hiroaki Kimura Claudia Lee Katsuhiro Hayashi Kensuke Yamauchi Norio Yamamoto Hiroyuki Tsuchiya Katsuro Tomita Michael Bouvet Robert M. Hoffman 《Journal of cellular biochemistry》2010,110(6):1439-1446
We investigated the cell‐killing efficacy of UV light on cancer cells expressing GFP in the nucleus and RFP in the cytoplasm (dual‐color cells). After exposure to various doses of UVA, UVB, or UVC, apoptotic and viable cells were quantitated under fluorescence microscopy using dual‐color 143B human osteosarcoma cells, HT‐1080 human fibrosarcoma cells, Lewis lung carcinoma (LLC), and XPA‐1 human pancreatic cancer cells in vitro. UV‐induced cancer cell death was wave‐length and dose dependent, as well as cell‐line dependent. After UVA exposure, most cells were viable even when the UV dose was increased up to 200 J/m2. With UVB irradiation, cell death was observed with irradiation at 50 J/m2. For UVC, as little as 25 J/m2 UVC irradiation killed approximately 70% of the 143B dual‐color cells. This dose of UVB or UVA had almost no effect on the cancer cells. UV‐induced cancer cell death varied among the cell lines. Cell death began about 4 h after irradiation and continued until 10 h after irradiation. UVC exposure also suppressed cancer cell growth in nude mice in a model of minimal residual cancer (MRC). No apparent side effects of UVC exposure were observed. This study opens up the possibility of UVC treatment for MRC after surgical resection. J. Cell. Biochem. 110: 1439–1446, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
82.
Takeshi Nishikawa Akihiro Yoshida Amit Khanal Manabu Habu Izumi Yoshioka Kuniaki Toyoshima Tadamichi Takehara Tatsuji Nishihara Katsuro Tachibana Kazuhiro Tominaga 《Gerodontology》2010,27(3):199-206
doi:10.1111/j.1741‐2358.2009.00325.x A study of the efficacy of ultrasonic waves in removing biofilms Objective: The removal of adherent biofilms was assessed using ultrasonic waves in a non‐contact mode. Materials and Methods: In in vitro experiments, Streptococcus mutans (S. mutans) biofilms were exposed to ultrasonic waves at various frequencies (280 kHz, 1 MHz, or 2 MHz), duty ratios (0–90%), and exposure times (1–3 minutes), and the optimal conditions for biofilm removal were identified. Furthermore, the effect of adding a contrast medium, such as micro bubbles (Sonazoid®), was examined. The spatial distribution and architecture of S. mutans biofilms before and after ultrasonic wave exposure were examined via scanning electron microscopy. The biofilm removal effect was also examined in in vivo experiments, using a custom‐made oral cleaning device. Results: When a 280 kHz probe was used, the biofilm‐removing effect increased significantly compared to 1 and 2 MHz probes; more than 80% of the adherent biofilm was removed with a duty cycle of 50–90% and a 3 minutes exposure time. The maximum biofilm‐removing effect was observed with a duty cycle of 80%. Furthermore, the addition of micro bubbles enhanced this biofilm‐removing effect. In in vivo experiments, moderate biofilm removal was observed when a 280 kHz probe was used for 5 minutes. Conclusions: This study demonstrated that ultrasonic wave exposure in a non‐contact mode effectively removed adherent biofilms composed of S. mutans in vitro. 相似文献
83.
In chloroplasts and nuclei of Spirogyra separated by discontinuoussucrose dnesity gradient centrifugation, five types of nucleicacids were found by MAK column chromatography; tRNA, low molecularweight rRNA, DNA, light and heavy rRNAs. Chloroplast rRNA was found to differ from cytoplasmic rRNA,by comparative studies on its base composition, its elutionpattern by MAK column chromatography and its sedimentation profilewith sucrose density gradient centrifugation. Molecular species of chloroplast DNA differed from those ofnuclear DNA in their thermal denaturation points (Tm), theirbehaviour on an IRC-50 column, their buoyant density in CsCland their base analyses. (Received September 13, 1972; ) 相似文献
84.
A Molecular Phylogeny of Lilium in the Internal Transcribed Spacer Region of Nuclear Ribosomal DNA 总被引:4,自引:0,他引:4
Tomotaro Nishikawa Keiichi Okazaki Tae Uchino Katsuro Arakawa Tsukasa Nagamine 《Journal of molecular evolution》1999,49(2):238-249
Phylogenetic relationships among 55 species of Lilium, Cardiocrinum giganteum, and Nomocharis saluenensis were inferred from nucleotide sequence variations in the internal transcribed spacer (ITS) regions of 18S–25S nuclear ribosomal
DNA. The phylogeny derived from ITS sequences estimated using maximum-likelihood methods indicated that (1) most of the species
construct their own clade according to the classification based on morphological features at the section level; (2) section
Daurolirion is not independent of Sinomartagon, and it is appropriate to integrate two sections as Sinomartagon; (3) it is appropriate that L. henryi and L. bulbiferum are classified into subsection 6a and Sinomartagon–Daurolirion, respectively; (4) subsection 6b is much closer to Sinomartagon than subsection 6a and Archelirion, and it arose directly from Sinomartagon; and (5) Lilium is much closer to Nomocharis than Cardiocrinum. Phylogenetic estimation using sequences of the ITS region is suitable at the levels of genus, section, and most of subsection.
Received: 18 December 1998 / Accepted: 14 March 1999 相似文献
85.
86.
87.
Tomohiko Matsuzawa Masahiro Watanabe Yusuke Nakamichi Zui Fujimoto Katsuro Yaoi 《Journal of structural biology》2019,205(1):84-90
Isoprimeverose-producing enzymes (IPases) release isoprimeverose (α-d-xylopyranosyl-(1?→?6)-d-glucopyranose) from the non-reducing end of xyloglucan oligosaccharides. Aspergillus oryzae IPase (IpeA) is classified as a member of the glycoside hydrolase family 3 (GH3); however, it has unusual substrate specificity compared with other GH3 enzymes. Xylopyranosyl branching at the non-reducing ends of xyloglucan oligosaccharides is vital for IpeA activity. We solved the crystal structure of IpeA with isoprimeverose at 2.4?Å resolution, showing that the structure of IpeA formed a dimer and was composed of three domains: an N-terminal (β/α)8 TIM-barrel domain, α/β/α sandwich fold domain, and a C-terminal fibronectin-like domain. The catalytic TIM-barrel domain possessed a catalytic nucleophile (Asp300) and acid/base (Glu524) residues. Interestingly, we found that the cavity of the active site of IpeA was larger than that of other GH3 enzymes, and subsite ?1′ played an important role in its activity. The glucopyranosyl and xylopyranosyl residues of isoprimeverose were located at subsites ?1 and ?1′, respectively. Gln58 and Tyr89 contributed to the interaction with the xylopyranosyl residue of isoprimeverose through hydrogen bonding and stacking effects, respectively. Our findings provide new insights into the substrate recognition of GH3 enzymes. 相似文献
88.
Katsuro Urata Toshio Satoh 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,841(2):201-207
The mechanism of anaerobic reduction of NO2? to N2O in a photodenitrifier, Rhodopseudomonas sphaeroides forma sp. denitrificans, was investigated. With ascorbate-reduced phenazine methosulfate (PMS) as the electron donor, the nitrite reductase of this photodenitrifier reduced NO2? to NO and a trace amount of N2O. With dithionite-reduced benzyl viologen as the electron donor, the major product of NO2? reduction was NH2OH, and a trace amount of N2O was also produced. The nitrate reductase itself had no NO reductase activity with ascorbate-reduced PMS. It was concluded that the essential product of NO2? reduction by the purified nitrite reductase is NO. Chromatophore membranes stoichiometrically produced N2O from NO2? with any electron donor, such as dithionite-redduced benzyl viologen, ascorbate-reduced PMS or NADH/FMN. The membranes also contrained activity of NO reduction of N2O with either ascorbate-reduced PMS or duroquinol. The NO reductase activity with duroquinol was inhibited by antimycin A. Stoichiometric production of N2O from N2? also was observed in the reconstituted NO2? reduction system which contained the cytochrome bc1 complex, cytochrome c2, the nitrite reductase and duroquinol as the electron donor. The preparation of the cytochrome bc1 complex itself contianed NO reductase activity. From these results the mechanism of NO2? reduction to N2O in this photodenitrifier was determined as the nitrite reductase reducing NO2? to NO with electrons from the cytochrome bc1 complex, and NO subsequently being reduced, without release, to N2O with electrons from the cytochrome bc1 complex by the NO reductase, which is closely associated with the complex. 相似文献
89.
Naoyuki Maeda Shouya Horochi Yasuhiro Hasegawa Tomohito Iwasaki Nobutake Nakatani Taku Miyasho Katsuro Hagiwara Hiroshi Yokota Yasuhiro Funatsu 《化学与生物多样性》2023,20(4):e202200924
The hepatitis E virus (HEV) causes a common infectious disease that infects pigs, wild boars, deer, and humans. In most cases, humans are infected by eating raw meat. Some essential oils have been reported to exhibit antiviral activities. In this study, in order to investigate the anti-HEV properties of essential oils, the immunoreactivities of HEV antigen proteins against the relevant antibodies were analyzed after the HEV antigens underwent treatment with various essential oils. The essential oils extracted from the tea tree, which was previously reported to exhibit antiviral activity, lavender, and lemon had strongly reduced activity. We found that treatment with the essential oil prepared from Sakhalin spruce was associated with the strongest reduction in immunoreactivity of HEV antigen protein(s) among the tested substances. The main volatile constituents of Sakhalin spruce essential oil were found to be bornyl acetate (32.30 %), α-pinene (16.66 %), camphene (11.14 %), camphor (5.52 %), β-phellandrene (9.09 %), borneol (4.77 %), and limonene (4.57 %). The anti-HEV properties of the various components of the essential oils were examined: treatment with bornyl acetate, the main component of Sakhalin spruce oil, α-pinene, the main component of tea tree oil, and limonene, the main component of lemon oil, resulted in a strong reduction in HEV antigen immunoreactivity. These results indicate that each main component of the essential oils plays an important role in the reduction of the immunoreactivity of HEV antigen protein(s); they also suggest that Sakhalin spruce essential oil exhibits anti-HEV activity. In a formulation with the potential to eliminate the infectivity of HEV in foodborne infections, this essential oil can be applied as an inactivating agent for meat processing and cooking utensils, such as knives and chopping boards. 相似文献