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81.
Motoyoshi Hongo Ayaaki Ishizaki Masaru Uyeda 《Bioscience, biotechnology, and biochemistry》2013,77(1):141-145
At maximum production of l-glutamic acid, the oxidation-reduction potential of the culture broth in l-glutamic acid fermentation showed a stable value of 9.0 to 9.6 as rH value. When biotin concentration in the medium was high (40γ/liter), the production of l-glutamic acid decreased, and the rH was 8.0 and it was out of accordance with that of the control (biotin-poor; 2γ/liter). Under “less-aerobic” conditions, its rH rose to 10.4.From these results, it was concluded that the rH during maximum production of l-glutamic acid showed a stable value affected actively by the redox system, l-glutamic acid/α-ketoglutaric acid and 相似文献
82.
Motoo MotooShibata Masaru Uyeda Yutaka Kido Yuki Fujimoto Yuji Takano Yukie Yoshioka 《Bioscience, biotechnology, and biochemistry》2013,77(12):3377-3382
Streptomyces sp. No. B-1625, which was identified as a strain of Streptomyces antibioticus, is a typical producer of actinomycin, but also produces minor acidic antibiotic components (FA), besides actinomycins X2, D and X0β. The FA-components, which were obtained with a high-producing mutant, 11M-21, showed antibacterial and antitumor activities, and also similar visible and UV absorption spectra to those characteristic of actinomycin. The FA-components were separated into five components, FA1 FA2α, FA2β, FA3α and FA3β, on TLC. Among them, one component, FA3β, isolated in a purified state as an orange powder, has a composition of C, 52.97: H, 6.34: N, 10.48%, and is active against B. subtilis at a MIC of 5mcg/ml. The FA3β component showed pKa′ of 5.4 and 12.0 and λmax at 443, 427 and 233 nm. From these properties, FA3β is considered to be an acidic actinomycin congener. 相似文献
83.
The morphological properties of the twelve previously described HM-phages were examined by electron microscopy. Specimens were prepared by air-drying and shadow-casting method using purified phage suspensions. As a result, the HM-phages were classified into three morphologically distinct groups, 1, 11 and 111. Group 1 phages were HM 1, HM 2, HM 8, HM 9, HM 10, HM 11 and HM 12. These phages had a spherical head about 100 mμ in diameter and a rudimentary tail. Group 11 phages were HM 3, HM 4, HM 5 and HM 6. These phages had a spherical head about 100 mμ in diameter and a tail with contractile sheath, and the normal tail of these phages was about 100 mμ in length, and the contracted sheath was about 50 mμ in length, Group 111 phage was HM 7 alone. This phage had a spherical head about 120 mμ in diameter and a relatively long tail about 350 mμ in length. 相似文献
84.
Tetsu Ando Yuki Hasegawa Masaaki Uchiyama 《Bioscience, biotechnology, and biochemistry》2013,77(11):2935-2937
Bis(4-chloro-2-ethylphenyl) phenylphosphonate was metabolically transformed into the cor-responding cyclic ester, i.e., 6-chloro-4-methyl-2-phenyl-4/f-1,3,2-benzodioxaphosphorin 2-oxide, in houseflies in vivo. In a p-unsubstituted analog, hydroxylation at the para-position of an ester linkage occurred preferably to alpha-hydroxylation with subsequent cyclization. The cyclization was diastereomerically selective, giving predominantly the cis ester. The biological activities of synthesized and related cyclic esters were similar to but weaker than saligenin cyclic phosphorus esters lacking a methyl group at the 4-position. 相似文献
85.
Asuka Kamei Yuki Watanabe Fumika Shinozaki Akihito Yasuoka Takashi Kondo Tomoko Ishijima 《Bioscience, biotechnology, and biochemistry》2013,77(11):1893-1897
Effects of the administration of maple syrup extract (MSX) on hepatic gene expression were investigated in mice fed a high-fat diet. Gene annotation enrichment analysis based on gene ontology revealed some changes in the expression of genes related to lipid metabolism and the immune response in MSX-fed mice. Detailed analysis of these data indicated that MSX ingestion mitigates hepatic inflammation. 相似文献
86.
Tomoko Igawa Yuki Yanagawa Shin-ya Miyagishima Toshiyuki Mori 《Journal of plant research》2013,126(3):387-394
Angiosperms have a unique sexual reproduction system called “double fertilization.” One sperm cell fertilizes the egg and another sperm cell fertilizes the central cell. To date, plant gamete membrane dynamics during fertilization has been poorly understood. To analyze this unrevealed gamete subcellular behavior, live cell imaging analyses of Arabidopsis double fertilization were performed. We produced female gamete membrane marker lines in which fluorescent proteins conjugated with PIP2a finely visualized egg cell and central cell surfaces. Using those lines together with a sperm cell membrane marker line expressing GCS1-GFP, the double fertilization process was observed. As a result, after gamete fusion, putative sperm plasma membrane GFP signals were occasionally detected on the egg cell surface adjacent to the central cell. In addition, time-lapse imaging revealed that GCS1-GFP signals entered both the egg cell and the central cell in parallel with the sperm cell movement toward the female gametes during double fertilization. These findings suggested that the gamete fusion process based on membrane dynamics was composed of (1) plasma membrane fusion on male and female gamete surfaces, (2) entry of sperm internal membrane components into the female gametes, and (3) plasmogamy. 相似文献
87.
Fang Chen Yuki Tobimatsu Lisa Jackson Jin Nakashima John Ralph Richard A. Dixon 《The Plant journal : for cell and molecular biology》2013,73(2):201-211
We have recently described a hitherto unsuspected catechyl lignin polymer (C‐lignin) in the seed coats of Vanilla orchid and in cacti of one genus, Melocactus (Chen et al., Proc. Natl. Acad. Sci. USA. 2012, 109, 1772‐1777.). We have now determined the lignin types in the seed coats of 130 different cactus species. Lignin in the vegetative tissues of cacti is of the normal guaiacyl/syringyl (G/S) type, but members of most genera within the subfamily Cactoidae possess seed coat lignin of the novel C‐type only, which we show is a homopolymer formed by endwise β–O–4‐coupling of caffeyl alcohol monomers onto the growing polymer resulting in benzodioxane units. However, the species examined within the genera Coryphantha, Cumarinia, Escobaria and Mammillaria (Cactoideae) mostly had normal G/S lignin in their seeds, as did all six species in the subfamily Opuntioidae that were examined. Seed coat lignin composition is still evolving in the Cactaceae, as seeds of one Mammillaria species (M. lasiacantha) possess only C‐lignin, three Escobaria species (E. dasyacantha, E. lloydii and E. zilziana) contain an unusual lignin composed of 5‐hydroxyguaiacyl units, the first report of such a polymer that occurs naturally in plants, and seeds of some species contain no lignin at all. We discuss the implications of these findings for the mechanisms that underlie the biosynthesis of these newly discovered lignin types. 相似文献
88.
Yoko Yokoyama Naoki Kakudate Futoshi Sumida Yuki Matsumoto Gregg H. Gilbert Valeria V. Gordan 《PloS one》2013,8(3)
Background
Dental caries are largely preventable, and epidemiological evidence for a relationship between diet and oral health is abundant. To date, however, dentists’ perceptions about the role of diet and dentists’ practice patterns regarding diet counseling have not been clarified.Objective
The purposes of this study were to: (1) examine discordance between dentists’ perception of the importance of diet in caries treatment planning and their actual provision of diet counseling to patients, and (2) identify dentists’ characteristics associated with their provision of diet counseling.Design
The study used a cross-sectional study design consisting of a questionnaire survey in Japan.Participants
The study queried dentists working in outpatient dental practices who were affiliated with the Dental Practice-Based Research Network Japan (JDPBRN), which aims to allow dentists to investigate research questions and share experiences and expertise (n = 282).Measurement
Dentists were asked about their perceptions on the importance of diet and their practice patterns regarding diet counseling, as well as patient, practice, and dentist background data.Results
The majority of participants (n = 116, 63%) recognized that diet is “more important” to oral health. However, among participants who think diet is “more important” (n = 116), only 48% (n = 56) provide diet counseling to more than 20% of their patients. Multiple logistic regression analysis suggested that several variables were associated with providing diet counseling; dentist gender, practice busyness, percentage of patients interested in caries prevention, caries risk assessment, and percentage of patients who receive blood pressure screening.Conclusions
Some discordance exists between dentists’ perception of the importance of diet in caries treatment planning and their actual practice pattern regarding diet counseling to patients. Reducing this discordance may require additional dentist education, including nutritional and systemic disease concepts; patient education to increase perception of the importance of caries prevention; or removing barriers to practices’ implementation of counseling.Trial Registration
ClinicalTrials.gov NCT01680848相似文献89.
Sofia Theodoropoulou Katarzyna Brodowska Maki Kayama Yuki Morizane Joan W. Miller Evangelos S. Gragoudas Demetrios G. Vavvas 《PloS one》2013,8(1)
5-Aminoimidazole-4-carboxamide-1-β-4-ribofuranoside (AICAR), an analog of AMP is widely used as an activator of AMP-kinase (AMPK), a protein that regulates the responses of the cell to energy change. Recently, we showed that AICAR-induced AMPK activation inhibits the growth of retinoblastoma cells in vitro by decreasing cyclins and by inducing apoptosis and S-phase arrest. In this study, we investigated the effects of AMPK activator AICAR on the growth of retinoblastoma in vivo. Intraperitoneal injection of AICAR resulted in 48% growth inhibition of Y79 retinoblastoma cell tumors in mice. Tumors isolated from mice treated with AICAR had decreased expression of Ki67 and increased apoptotic cells (TUNEL positive) compared with the control. In addition, AICAR treatment suppressed significantly tumor vessel density and macrophage infiltration. We also showed that AICAR administration resulted in AMPK activation and mTOR pathway inhibition. Paradoxically observed down-regulation of p21, which indicates that p21 may have a novel function of an oncogene in retinoblastoma tumor. Our results indicate that AICAR treatment inhibited the growth of retinoblastoma tumor in vivo via AMPK/mTORC1 pathway and by apoptogenic, anti-proliferative, anti-angiogenesis mechanism. AICAR is a promising novel non-chemotherapeutic drug that may be effective as an adjuvant in treating Retinoblastoma. 相似文献
90.
Takayoshi Suzuki Yuki Kasuya Yukihiro Itoh Yosuke Ota Peng Zhan Kaori Asamitsu Hidehiko Nakagawa Takashi Okamoto Naoki Miyata 《PloS one》2013,8(7)
To find histone deacetylase 3 (HDAC3)-selective inhibitors, a series of 504 candidates was assembled using “click chemistry”, by reacting nine alkynes bearing a zinc-binding group with 56 azide building blocks in the presence of Cu(I) catalyst. Screening of the 504-member triazole library against HDAC3 and other HDAC isozymes led to the identification of potent and selective HDAC3 inhibitors T247 and T326. These compounds showed potent HDAC3 inhibition with submicromolar IC50s, whereas they did not strongly inhibit other isozymes. Compounds T247 and T326 also induced a dose-dependent selective increase of NF-κB acetylation in human colon cancer HCT116 cells, indicating selective inhibition of HDAC3 in the cells. In addition, these HDAC3-selective inhibitors induced growth inhibition of cancer cells, and activated HIV gene expression in latent HIV-infected cells. These findings indicate that HDAC3-selective inhibitors are promising candidates for anticancer drugs and antiviral agents. This work also suggests the usefulness of the click chemistry approach to find isozyme-selective HDAC inhibitors. 相似文献