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991.
Akira Asanome Jun-ichi Kawabe Motoki Matsuki Maki Kabara Yoshiki Hira Hiroki Bochimoto Atsushi Yamauchi Tatsuya Aonuma Naofumi Takehara Tsuyoshi Watanabe Naoyuki Hasebe 《Biochemical and biophysical research communications》2014
An immature vasa vasorum in the adventitia of arteries has been implicated in induction of the formation of unstable atherosclerotic plaques. Normalization/maturation of the vasa vasorum may be an attractive therapeutic approach for arteriosclerotic diseases. Nerve growth factor (NGF) is a pleotropic molecule with angiogenic activity in addition to neural growth effects. However, whether NGF affects the formation of microvessels in addition to innervation during pathological angiogenesis is unclear. In the present study, we show a new role for NGF in neovessels around injured arterial walls using a novel in vivo angiogenesis assay. 相似文献
992.
Takuya Kano Takeshi Kouzuki Satoru Mizuno Shuji Ueda Minoru Yamanoue Fumio Sakane Naoaki Saito Yasuhito Shirai 《Biochemical and biophysical research communications》2014
We previously reported that diacylglycerol kinase β (DGKβ) induces neurites and branches, contributing to higher brain function including emotion and memories. However, the detailed molecular mechanism of DGKβ function remains unknown. Therefore, we constructed various mutants of DGKβ and compared their enzyme activity, intracellular localization, and ability to induce neurites and branching in SH-SY5Y cells. 相似文献
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995.
Hiroyuki Arai Takuro Kawakami Tatsuya Osamura Takehiro Hirai Yoshiaki Sakai Masaharu Ishii 《Journal of bacteriology》2014,196(24):4206-4215
The ubiquitous opportunistic pathogen Pseudomonas aeruginosa has five aerobic terminal oxidases: bo3-type quinol oxidase (Cyo), cyanide-insensitive oxidase (CIO), aa3-type cytochrome c oxidase (aa3), and two cbb3-type cytochrome c oxidases (cbb3-1 and cbb3-2). These terminal oxidases are differentially regulated under various growth conditions and are thought to contribute to the survival of this microorganism in a wide variety of environmental niches. Here, we constructed multiple mutant strains of P. aeruginosa that express only one aerobic terminal oxidase to investigate the enzymatic characteristics and in vivo function of each enzyme. The Km values of Cyo, CIO, and aa3 for oxygen were similar and were 1 order of magnitude higher than those of cbb3-1 and cbb3-2, indicating that Cyo, CIO, and aa3 are low-affinity enzymes and that cbb3-1 and cbb3-2 are high-affinity enzymes. Although cbb3-1 and cbb3-2 exhibited different expression patterns in response to oxygen concentration, they had similar Km values for oxygen. Both cbb3-1 and cbb3-2 utilized cytochrome c4 as the main electron donor under normal growth conditions. The electron transport chains terminated by cbb3-1 and cbb3-2 generate a proton gradient across the cell membrane with similar efficiencies. The electron transport chain of aa3 had the highest proton translocation efficiency, whereas that of CIO had the lowest efficiency. The enzymatic properties of the terminal oxidases reported here are partially in agreement with their regulatory patterns and may explain the environmental adaptability and versatility of P. aeruginosa. 相似文献
996.
M. P. Ali Katsuhiko Yoshimatsu Tomohiro Suzuki Tatsuya Kato Enoch Y. Park 《Applied microbiology and biotechnology》2014,98(16):6973-6982
Antimicrobial peptides (AMPs), both synthetic and from natural sources, have raised interest recently as potential alternatives to antibiotics. Cyto-insectotoxin (Cit1a) is a 69-amino-acid antimicrobial peptide isolated from the venom of the central Asian spider Lachesana tarabaevi. The synthetic gene Cit1a fused with the enhanced green fluorescent protein (EGFP) gene was expressed as the EGFP-Cit1a fusion protein using a cysteine protease-deleted Bombyx mori nucleopolyhedrovirus (BmNPV-CP?) bacmid in silkworm larva and pupa. The antimicrobial effect of the purified protein was assayed using disk diffusion and broth microdilution methods. The minimum inhibitory concentration of EGFP-Cit1a was also measured against several bacterial strains and showed similar antimicrobial activity to that of the synthetic Cit1a reported earlier. The EGFP-Cit1a fusion protein showed antibiotic activity toward gram-positive and gram-negative bacteria at the micromolar concentration level. These results show that active Cit1a can be produced and purified in silkworm, although this peptide is insecticidal. This study demonstrates the potential of active Cit1a purified from silkworms to use as an antimicrobial agent. 相似文献
997.
Kaori Kanaya Kenji Kondo Keigo Suzukawa Takashi Sakamoto Shu Kikuta Kazunari Okada Tatsuya Yamasoba 《Cell and tissue research》2014,357(1):279-299
The pathogenesis of postviral olfactory disorder (PVOD) has not been fully elucidated. We investigated morphological changes and innate immune responses in the mouse olfactory mucosa induced by intranasal administration of polyinosinic-polycytidylic acid [Poly(I:C)], a synthetic analog of viral double-stranded RNA. Mice received three administrations of saline with or without Poly(I:C), once every 24 h. The olfactory mucosa was harvested at various intervals after the first administration (8 h, 3, 9 and 24 days). In the Poly(I:C) group, the number of apoptotic cells in the olfactory neuroepithelium had increased at 8 h. At 9 days, the olfactory neuroepithelium had severely degenerated and behavioral tests demonstrated that the mice showed signs of olfactory deterioration. At 24 days, the structure of the neuroepithelium had regenerated almost completely. Regarding the innate immune responses, many neutrophils had infiltrated the olfactory neuroepithelium at 8 h and had exuded into the nasal cavity by 3 days. Macrophages had also infiltrated the olfactory neuroepithelium at 8 h although to a lesser extent, but they still remained in the neuroepithelium at 24 days. Poly(I:C)-induced neuroepithelial damage was significantly inhibited by a neutrophil elastase inhibitor and was suppressed in neutropenic model mice. These findings suggest that the secondary damage caused by the neutrophil-mediated innate immune response plays an important role in the pathogenesis of PVOD. 相似文献
998.
Kazumasa Shirai Nobuyuki Inomata Shinji Mizoiri Mitsuto Aibara Yohey Terai Norihiro Okada Hidenori Tachida 《Gene》2014
When a population size is reduced, genetic drift may fix slightly deleterious mutations, and an increase in nonsynonymous substitution is expected. It has been suggested that past aridity has seriously affected and decreased the populations of cichlid fishes in Lake Victoria, while geographical studies have shown that the water levels in Lake Tanganyika and Lake Malawi have remained fairly constant. The comparably stable environments in the latter two lakes might have kept the populations of cichlid fishes large enough to remove slightly deleterious mutations. The difference in the stability of cichlid fish population sizes between Lake Victoria and the Lakes Tanganyika and Malawi is expected to have caused differences in the nonsynonymous/synonymous ratio, ω (= dN/dS), of the evolutionary rate. Here, we estimated ω and compared it between the cichlids of the three lakes for 13 mitochondrial protein-coding genes using maximum likelihood methods. We found that the lineages of the cichlids in Lake Victoria had a significantly higher ω for several mitochondrial loci. Moreover, positive selection was indicated for several codons in the mtDNA of the Lake Victoria cichlid lineage. Our results indicate that both adaptive and slightly deleterious molecular evolution has taken place in the Lake Victoria cichlids' mtDNA genes, whose nonsynonymous sites are generally conserved. 相似文献
999.
Kazumasa Ohashi Kaori Sampei Mami Nakagawa Naoto Uchiumi Tatsuya Amanuma Setsuya Aiba Masato Oikawa Kensaku Mizuno 《Molecular biology of the cell》2014,25(6):828-840
LIM-kinases (LIMKs) play crucial roles in various cell activities, including migration, division, and morphogenesis, by phosphorylating and inactivating cofilin. Using a bimolecular fluorescence complementation assay to detect the actin–cofilin interaction, we screened LIMK1 inhibitors and identified two effective inhibitors, damnacanthal (Dam) and MO-26 (a pyrazolopyrimidine derivative). These compounds have already been shown to inhibit Lck, a Src family tyrosine kinase. However, in vitro kinase assays revealed that Dam inhibited LIMK1 more effectively than Lck. Dam suppressed LIMK1-induced cofilin phosphorylation and deceleration of actin retrograde flow in lamellipodia in N1E-115 cells. Dam impaired CXCL12-induced chemotactic migration of Jurkat T lymphocytes and Jurkat-derived, Lck-deficient JCaM1.6 cells and also inhibited serum-induced migration and invasion of MDA-MB-231 breast carcinoma cells. These results suggest that Dam has the potential to suppress cell migration and invasion primarily through the inhibition of LIMK kinase activity. Topical application of Dam also suppressed hapten-induced migration of epidermal Langerhans cells in mouse ears. Dam provides a useful tool for investigating cellular and physiological functions of LIMKs and holds promise for the development of agents against LIMK-related diseases. The bimolecular fluorescence complementation assay system used in this study will provide a useful method to screen for inhibitors of various protein kinases. 相似文献
1000.
Yoshiaki Tabuchi Shigehito Wada Mika Ikegame Ayako Kariya Yukihiro Furusawa Nobuhiko Hoshi Tatsuya Yunoki Nobuo Suzuki Ichiro Takasaki Takashi Kondo Yoshihisa Suzuki 《Experimental Animals》2014,63(1):31-44
We have developed an immortalized oral epithelial cell line, ROE2, from fetal transgenic
rats harboring temperature-sensitive simian virus 40 large T-antigen gene. The cells grew
continuously at either a permissive temperature of 33°C or an intermediate temperature of
37°C. At the nonpermissive temperature of 39°C, on the other hand, growth decreased
significantly, and the Sub-G1 phase of the cell cycle increased, indicating that the cells
undergo apoptosis at a nonpermissive temperature. Histological and immunocytochemical
analyses revealed that ROE2 cells at 37°C had a stratified epithelial-like morphology and
expressed cytokeratins Krt4 and Krt13, marker proteins for oral nonkeratinized epithelial
cells. Global-scale comprehensive microarray analysis, coupled with bioinformatics tools,
demonstrated a significant gene network that was obtained from the upregulated genes. The
gene network contained 16 genes, including Cdkn1a, Fos,
Krt13, and Prdm1, and was associated mainly with the
biological process of skin development in the category of biological functions, organ
development. These four genes were validated by quantitative real-time polymerase chain
reaction, and the results were nearly consistent with the microarray data. It is therefore
anticipated that this cell line will be useful as an in vitro model for
studies such as physiological functions, as well as for gene expression in oral epithelial
cells. 相似文献