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991.
Fujita R Tanaka Y Saihara Y Yamakita M Ando D Koyama K 《Journal of physiological anthropology》2011,30(5):195-201
The objectives of this paper were to determine the level of oxidative stress in atrophied gastrocnemius, and to verify the effect of molecular hydrogen (H2) saturated alkaline electrolyzed water (HSW) on gastrocnemius atrophy by modifying the redox status, indicated by 8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), and superoxide dismutase (SOD)-like activity. Female Wistar rats were divided into four groups: (1) the control (CONT); (2) the Hindlimb unloading (HU, for 3 weeks) given purified normal water (HU-NW); (3) the HU given alkaline electrolyzed reduced water (HU-AEW); and (4) the HU given HSW (HU-HSW). We showed that 8-OHdG, but not MDA, significantly increased by 149% and 145% in HU-NW and HU-AEW, respectively, when compared with CONT. In contrast, there was a trend toward suppression in 8-OHdG levels (increased by 95% compared with CONT) by treatment of HSW, though this effect was not prominent. Additionally, SOD-like activity significantly increased in both HU-NW (184%) and HU-AEW (199%) when compared with CONT. This result suggests the elevation of O2-· in the atrophied gastrocnemius. However, upregulation of SOD-like activity in the HU-HSW was increased by only 169% compared with CONT, though this difference is too small to detect statistical significance. HU led to 13% and 15% reduction of gastrocnemius wet weights in HU-NW and HU-AEW, respectively, compared with CONT. And the reduction of gastrocnemius wet weights in HU-HSW was attenuated by 7% compared with CONT. The gastrocnemius wet weights in the HU-HSW group were significantly greater than those in the HU-AEW, but not statistically significant with HU-NW. These results indicate that HU causes an increase in oxidative stress, but, in this experimental protocol, continuous consumption of HSW during HU does not demonstrate successful attenuation of oxidative stress and HU-mediated gastrocnemius atrophy. 相似文献
992.
Purpose
Age-related macular degeneration caused by choroidal neovascularization (CNV) remains difficult to be treated despite the recent advent of several treatment options. In this study, we investigated the in vivo angiogenic control by intravenous injection of polyion complex (PIC) micelle encapsulating plasmid DNA (pDNA) using a mice CNV model.Methods
The transfection efficiency of the PIC micelle was investigated using the laser-induced CNV in eight-week-old male C57 BJ/6 mice. Firstly, each mouse received intravenous injection of micelle encapsulating pDNA of Yellow Fluorescent Protein (pYFP) on days 1,3 and 5. The expression of YFP was analyzed using fluorescein microscopy and western blotting analysis. In the next experiments, each mouse received intravenous injection of micelle encapsulating pDNA of soluble Fms-like tyrosine kinase-1 (psFlt-1) 1,3 and 5 days after the induction of CNV and the CNV lesion was analyzed by choroidal flatmounts on day 7.Results
Fluorescein microscopy and western blotting analysis revealed that the expression of YFP was confirmed in the CNV area after injection of the PIC micelle, but the expression was not detected neither in mice that received naked pDNA nor those without CNV. Furthermore, the CNV area in the mice that received intravenous injection of the psFlt-1-encapsulated PIC micelle was significantly reduced by 65% compared to that in control mice (p<0.01).Conclusions
Transfection of sFlt-1 with the PIC micelle by intravenous injection to mice CNV models showed significant inhibition of CNV. The current results revealed the significant potential of nonviral gene therapy for regulation of CNV using the PIC micelle encapsulating pDNA. 相似文献993.
994.
Norio Arakaki Yasuhiro Hokama Ayako Yamaguchi Sadao Wakamura 《Applied Entomology and Zoology》2013,48(3):331-335
To examine the local distribution of Dasylepida ishigakiensis Niijima et Kinoshita larvae (Coleoptera: Scarabaeidae) on Miyako Island and Ishigaki Island, a survey was conducted in hayfields on the two Islands in February and March 2011. Symptoms of white grub infestation, such as patches of wilted grass and thin, yellow grass stands, were observed in some of the 20 hayfields surveyed on Miyako Island. Three species of white grub were observed there: D. ishigakiensis, Anomala cpustulata cpustulata Matsumura in Hirayama, and Anomala albopilosa (Hope), in the ratio 92:7:1, respectively. The mean population density of D. ishigakiensis in the hayfields was 54.3 m?2 and the maximum was 225 m?2. No significant relationship was found between the damage levels of hay grass and the D. ishigakiensis larval densities. In contrast, no damage was observed in the 14 hayfields surveyed on Ishigaki Island, although some D. ishigakiensis larvae were found at a low density in 4 hayfields. In 2006, no D. ishigakiensis larvae were found in sugarcane fields on this island in a separately conducted intensive survey. These observations may suggest that D. ishigakiensis larvae are present in hayfields at a low density but that few individuals occur in sugarcane fields on Ishigaki Island. 相似文献
995.
996.
Marie Kunihiro Yasuhiro Ozeki Yuichi Nogi Natsuko Hamamura Robert A. Kanaly 《Applied and environmental microbiology》2013,79(14):4410-4420
A soil bacterium, designated strain KK22, was isolated from a phenanthrene enrichment culture of a bacterial consortium that grew on diesel fuel, and it was found to biotransform the persistent environmental pollutant and high-molecular-weight polycyclic aromatic hydrocarbon (PAH) benz[a]anthracene. Nearly complete sequencing of the 16S rRNA gene of strain KK22 and phylogenetic analysis revealed that this organism is a new member of the genus Sphingobium. An 8-day time course study that consisted of whole-culture extractions followed by high-performance liquid chromatography (HPLC) analyses with fluorescence detection showed that 80 to 90% biodegradation of 2.5 mg liter−1 benz[a]anthracene had occurred. Biodegradation assays where benz[a]anthracene was supplied in crystalline form (100 mg liter−1) confirmed biodegradation and showed that strain KK22 cells precultured on glucose were equally capable of benz[a]anthracene biotransformation when precultured on glucose plus phenanthrene. Analyses of organic extracts from benz[a]anthracene biodegradation by liquid chromatography negative electrospray ionization tandem mass spectrometry [LC/ESI(−)-MS/MS] revealed 10 products, including two o-hydroxypolyaromatic acids and two hydroxy-naphthoic acids. 1-Hydroxy-2- and 2-hydroxy-3-naphthoic acids were unambiguously identified, and this indicated that oxidation of the benz[a]anthracene molecule occurred via both the linear kata and angular kata ends of the molecule. Other two- and single-aromatic-ring metabolites were also documented, including 3-(2-carboxyvinyl)naphthalene-2-carboxylic acid and salicylic acid, and the proposed pathways for benz[a]anthracene biotransformation by a bacterium were extended. 相似文献
997.
Pseudomonas putida F1 can metabolize toluene, ethylbenzene, and benzene for growth. Previously, we identified proteins involved in the utilization of these compounds by P. putida F1 through culture in liquid media. However, it was unclear whether laboratory analysis of bacterial activity and catabolism accurately reflected the soil environment. We identified proteins involved in the degradation of toluene, ethylbenzene, and benzene growth in soil using two-dimensional gel electrophoresis (2-DE) or standard SDS-PAGE combined with liquid chromatography–tandem mass spectrometry (LC–MS/MS). According to 2-DE/LC–MS/MS analysis, 12 of 22 key enzymes involved in the degradation of toluene, ethylbenzene, and benzene were detected. In standard SDS-PAGE/LC–MS/MS analysis of soil with ethylbenzene, approximately 1,260 cellular proteins were identified in P. putida F1. All key enzymes and transporter and sensor proteins involved in ethylbenzene degradation were up-regulated similar to that noted in liquid cultures. In P. putida F1, aromatic hydrocarbon response in soil is the same as that observed in liquid media. 相似文献
998.
Akinori Inamura Yasuhiro Adachi Takao Inoue Yeting He Nobuko Tokuda Takashi Nawata Satoshi Shirao Sadahiro Nomura Masami Fujii Eiji Ikeda Yuji Owada Michiyasu Suzuki 《Neurochemical research》2013,38(8):1641-1647
The blood–brain-barrier (BBB) is formed by different cell types, of which brain microvascular endothelial cells are major structural constituents. The goal of this study was to examine the effects of cooling on the permeability of the BBB with reference to tight junction formation of brain microendothelial cells. The sensorimotor cortex above the dura mater in adult male Wistar rats was focally cooled to a temperature of 5 °C for 1 h, then immunostaining for immunoglobulin G (IgG) was performed to evaluate the permeability of the BBB. Permeability produced by cooling was also evaluated in cultured murine brain endothelial cells (bEnd3) based on measurement of trans-epithelial electric resistance (TEER). Immunocytochemistry and Western blotting of proteins associated with tight junctions in bEnd3 were performed to determine protein distribution before and after cooling. After focal cooling of the rat brain cortex, diffuse immunostaining for IgG was observed primarily around the small vasculature and in the extracellular spaces of parenchyma of the cortex. In cultured bEnd3, TEER significantly decreased during cooling (15 °C) and recovered to normal levels after rewarming to 37 °C. Immunocytochemistry and Western blotting showed that claudin-5, a critical regulatory protein for tight junctions, was translocated from the membrane to the cytoplasm after cooling in cultured bEnd3 cells. These results suggest that focal brain cooling may open the BBB transiently through an effect on tight junctions of brain microendothelial cells, and that therapeutically this approach may allow control of BBB function and drug delivery through the BBB. 相似文献
999.
1000.
Kitamura H Yamamoto S Nakase H Matsuura M Honzawa Y Matsumura K Takeda Y Uza N Nagata K Chiba T 《Biochemical and biophysical research communications》2011,(2):599-604