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101.
Masakazu Miyakado Nobuo Ohno Yoshitoshi Okuno Masachika Hirano Keimei Fujimoto Hirosuke Yoshioka 《Bioscience, biotechnology, and biochemistry》2013,77(1):267-272
In connection with disclosure of a new class of insecticides, the modified phenylacetates, six new optically active α-isopropy-4-substituted phenylacetic acids whose substituents are respectively 4-methyl,4-methoxy, 4-fluoro, 4-chloro, 4-bromo and 3,4-methylenedioxy group were prepared by optical resolution and their absolute configurations were determined by comparative ORD with α-isopropylphenylacetic acid derivatives whose absolute configuration is known as (S)-(²). Esters of the (S)-(²)-acids with 5-benzyl-3-furylmethanol were nearly twice toxic to Musca domestica than those of the racemic esters. Optical purities of the resolved acids were determined by GLC and NMR (with Eu-FOD) as (?)-methyl esters. 相似文献
102.
Masao Fujimoto Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(10):1991-1997
The inhibitory action of compressed hydrocarbon gases on the growth of the yeast Saccharomyces cerevisiae was investigated quantitatively by microcalorimetry. Both the 50% inhibitory pressure (IP50) and the minimum inhibitory pressure (MIP), which are regarded as indices of the toxicity of hydrocarbon gases, were determined from growth thermograms. Based on these values, the inhibitory potency of the hydrocarbon gases increased in the order methane << ethane < propane < i-butane < n-butane. The toxicity of these hydrocarbon gases correlated to their hydrophobicity, suggesting that hydrocarbon gases interact with some hydrophobic regions of the cell membrane. In support of this, we found that UV absorbing materials at 260 nm were released from yeast cells exposed to compressed hydrocarbon gases. Additionally, scanning electron microscopy indicated that morphological changes occurred in these cells. 相似文献
103.
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
104.
Akira Kuninaka Masao Fujimoto Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(3):603-610
Sixteen 2′→5′ dinucleotides; (2′–5′)pA-A, pA-G, pA-C, pA-U, pG-A, pG-G, pG-C, pG-U, pC-A, pC-G, pC-C, pC-U, pU-A, pU-G, pU-C, and pU-U were detected in nuclease P1 digest of a technical grade yeast RNA by means of gel filtration on Sephadex G-10, DEAE-Sephadex A-25 column chromatography in the presence of 7 m urea, paper electrophoresis and paper chromatography. Content of each dinucleotide was about 0.1 to 0.6% of the digest. As the sixteen 2′→5′ dinucleotides were found in all of the digests of technical grade RNA preparations tested, each polynucleotide chain in the preparations may be concluded to contain several per cent of the 2′–5′ minor phosphodiester linkages in addition to the 3′–5′ major phosphodiester linkages. 相似文献
105.
Yasumasa Kuwahara Yayoi Ichiki Masashi Morita Yasuhisa Asano 《Bioscience, biotechnology, and biochemistry》2013,77(8):1320-1323
(2-Nitroethyl)benzene was identified as a major component of the flower scent of the Japanese loquat Eriobotrya japonica [Rosales: Rosaceae], together with p-methoxybenzaldehyde and methyl p-methoxybenzoate. The corresponding volatiles from chopped leaves did not contain these three compounds. This is the first time that 1-nitro-2-phenyl-ethane has been demonstrated to be a natural product among Japanese plants, although two Japanese millipedes are known to possess the same aromatics. 相似文献
106.
Masao Fujimoto Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(7):1111-1119
Nuclease P1 from Penicillium citrinum was found to be produced in a form of complex with malonogalactan (a galactan, 1, 5-β-galactofuranoside polymer esterfied with malonic acid at position 3) in the culture on wheat bran. Neither nuclease P1-malonogalactan complex nor malonogalactan was produced in a liquid medium. Nuclease P1-malonogalactan complexes, P1-MG I, II, and III were purified from an aqueous extract of the culture on wheat bran. The most anionic complex, P1-MG III, was composed of the protein, carbohydrate and malonic acid in the ratio of 1: 2.6: 0.5 (w/w). The complex was not dissociated by purification procedures including fractionations with acetone and ammonium sulfate, gel filtration and DEAE-cellulose chromatography. A malonogalactan-specific carboxylesterase was found in culture of the same mold on wheat bran. Nuclease P1-malonogalactan was demalonylated by the esterase to yield nuclease P1-galactan. The binding of nuclease P1 to galactan was rather loose so that nuclease P1-galactan complex was partially dissociated by DEAE-cellulose chromatography. Attempt to reconstitute the complex from nuclease P1 and malonogalactan upon mixing was unsuccessful. Exogenously supplemented nuclease P1 did not associate with malonogalactan in the growing culture on wheat bran, either.Several extracellular enzymes such as RNase, β-galactosidase and protease were also found in a form of complex with malonogalactan in the culture on wheat bran. 相似文献
107.
Hitomi Ueno Hajime Okita Shingo Akimoto Kenichiro Kobayashi Kazuhiko Nakabayashi Kenichiro Hata Junichiro Fujimoto Jun-ichi Hata Masahiro Fukuzawa Nobutaka Kiyokawa 《PloS one》2013,8(4)
A number of specific, distinct neoplastic entities occur in the pediatric kidney, including Wilms’ tumor, clear cell sarcoma of the kidney (CCSK), congenital mesoblastic nephroma (CMN), rhabdoid tumor of the kidney (RTK), and the Ewing’s sarcoma family of tumors (ESFT). By employing DNA methylation profiling using Illumina Infinium HumanMethylation27, we analyzed the epigenetic characteristics of the sarcomas including CCSK, RTK, and ESFT in comparison with those of the non-neoplastic kidney (NK), and these tumors exhibited distinct DNA methylation profiles in a tumor-type-specific manner. CCSK is the most frequently hypermethylated, but least frequently hypomethylated, at CpG sites among these sarcomas, and exhibited 490 hypermethylated and 46 hypomethylated CpG sites in compared with NK. We further validated the results by MassARRAY, and revealed that a combination of four genes was sufficient for the DNA methylation profile-based differentiation of these tumors by clustering analysis. Furthermore, THBS1 CpG sites were found to be specifically hypermethylated in CCSK and, thus, the DNA methylation status of these THBS1 sites alone was sufficient for the distinction of CCSK from other pediatric renal tumors, including Wilms’ tumor and CMN. Moreover, combined bisulfite restriction analysis could be applied for the detection of hypermethylation of a THBS1 CpG site. Besides the biological significance in the pathogenesis, the DNA methylation profile should be useful for the differential diagnosis of pediatric renal tumors. 相似文献
108.
Toshiaki Nakano Rikiya Kamei Takashi Fujimura Yuki Takaoka Ayane Hori Chia-Yun Lai Kuei-Chen Chiang Yayoi Shimada Naoya Ohmori Takeshi Goto Kazuhisa Ono Chao-Long Chen Shigeru Goto Seiji Kawamoto 《PloS one》2016,11(4)
Nuclear antigens are known to trigger off innate and adaptive immune responses. Recent studies have found that the complex of nucleic acids and core histones that are derived from damaged cells may regulate allergic responses. However, no fundamental study has been performed concerning the role of linker histone H1 in mast cell-mediated type I hyperreactivity. In this study, we explored the impact of histone H1 on mast cell-mediated allergic responses both in vitro and in vivo. In the course of a bona-fide experimental allergen sensitization model upon co-injection with alum adjuvant, ovalbumin (OVA), but not PBS, induced elevated levels of circulating histone H1. Intranasal challenge with histone H1 to OVA/alum- (but not PBS/alum)-sensitized mice induced significantly severer symptoms of allergic rhinitis than those in mice sensitized and challenged with OVA. A monoclonal antibody against histone H1 not only suppressed mast cell degranulation, but also ameliorated OVA-induced nasal hyperreactivity and IgE-mediated passive cutaneous anaphylaxis. Our present data suggest that nuclear histone H1 represents an alarmin-like endogenous mediator acting on mast cells, and that its blockage has a therapeutic potential for mast cell-mediated type I hyperreactivity. 相似文献
109.
Shinji Sato Akihiro Murakami Akiko Kuwajima Kazuhiko Takehara Tsuneyo Mimori Atsushi Kawakami Michiaki Mishima Takafumi Suda Mariko Seishima Manabu Fujimoto Masataka Kuwana 《PloS one》2016,11(4)
ObjectiveAutoantibodies to melanoma differentiation-associated gene 5 (MDA5) are specifically expressed in patients with dermatomyositis (DM) and are associated with a subset of DM patients with rapidly progressive interstitial lung disease (RP-ILD). Here, we examined the clinical utility of a newly developed enzyme-linked immunosorbent assay (ELISA) system for detecting these antibodies.MethodsHere we developed an improved ELISA for detecting anti-MDA5 antibodies. We then performed a multicenter clinical study involving 8 medical centers and enrolled 242 adult patients with polymyositis (PM)/DM, 190 with non-PM/DM connective tissue disease (CTD), 154 with idiopathic interstitial pneumonia (IIP), and 123 healthy controls. Anti-MDA5 antibodies in the patients’ serum samples were quantified using our newly developed ELISA, and the results were compared to those obtained using the gold-standard immunoprecipitation (IP) assay. In addition, correlations between the ELISA-quantified anti-MDA5 antibodies and clinical characteristics were evaluated.ResultsIn patients with PM/DM, the anti-MDA5 antibody measurements obtained from the ELISA and IP assay were highly concordant; the ELISA exhibited an analytical sensitivity of 98.2%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 99.5% (compared to the IP assay). Anti-MDA5 antibodies were detected in 22.7% of the DM patients, but not in any of the patients with PM, non-PM/DM CTD, or IIP. Clinically amyopathic DM, RP-ILD, arthritis, and fever were more prevalent in DM patients who were anti-MDA5 antibody-positive than in those who were antibody-negative (P ≤ 0.0002 for all comparisons). In addition, anti-MDA5 antibody-positive patients with RP-ILD exhibited higher antibody levels than those without RP-ILD (P = 0.006).ConclusionOur newly developed ELISA can detect anti-MDA5 antibodies as efficiently as the gold standard IP assay and has the potential to facilitate the routine clinical measurement of anti-MDA5 antibodies in patients who suspected to have DM. 相似文献