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91.
Yoshiyuki Tohno Setsuko Tohno Takao Oishi Takeshi Minami Pongsak Khanpetch Cho Azuma Ranida Quiggins 《Biological trace element research》2014,161(1):78-84
To elucidate compositional changes of the ligament with aging, the authors investigated age-related changes of elements in the ligamentum capitis femoris (LCF) of monkeys with a wide range of ages by direct chemical analysis. Used rhesus and Japanese monkeys consisted of 9 males and 22 females, ranging in age from newborn to 31 years (average age?=?10.4?±?10.9 years). After incineration with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that the P content decreased significantly in the LCFs of monkeys with aging, but other six element contents, Ca, S, Mg, Zn, Fe, and Na, did not change significantly with aging. Assuming that the P content indicated the active cell density and the S content indicated the protein amount, an age-related change of the mass ratio of P/S was examined in the LCFs. The mass ratio of P/S decreased significantly in the LCFs in childhood. Regarding the relationships among elements, significant direct correlations were found among the Ca, P, S, and Mg contents in the LCFs. It was suggested that the active cell density of the connective tissue cells might decrease significantly in the LCF in childhood. 相似文献
92.
Peroxyoxalate chemiluminescence enhanced by oligophenylenevinylene fluorophores in the presence of various surfactants
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The effect of several surfactants on peroxyoxalate chemiluminescence (PO‐CL) using oligophenylenevinylene fluorophores was investigated. Among several oligophenylenevinylenes consisting of stilbene units, linearly conjugated ones, such as distyrylbenzene and distyrylstilbene, effectively enhanced PO‐CL efficiency. Various effects of anionic, cationic, amphoteric and non‐ionic surfactants on the CL efficiency of PO‐CL were determined using three oxalates and the distyrylbenzene fluorophore. Anionic and non‐ionic surfactants effectively enhanced CL efficiency, in contrast to the negative effect of cationic and amphoteric surfactants. Non‐ionic surfactants were also effective in CL reactions of oxalates bearing dodecyl ester groups by the hydrophobic interaction between their alkyl chains. Considering these results, the surfactants not only increase the concentrations of water‐insoluble interacting species in the hydrophobic micelle cores, but also control rapid degradation of the oxalates by alkaline hydrolysis. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
93.
To know the molecular systems basically flooding conditions in soybean, biophoton emission measurements and proteomic analyses were carried out for flooding-stressed roots under light and dark conditions. Photon emission was analyzed using a photon counter. Gel-free quantitative proteomics were performed to identify significant changes proteins using the nano LC–MS along with SIEVE software. Biophoton emissions were significantly increased in both light and dark conditions after flooding stress, but gradually decreased with continued flooding exposure compared to the control plants. Among the 120 significantly identified proteins in the roots of soybean plants, 73 and 19 proteins were decreased and increased in the light condition, respectively, and 4 and 24 proteins were increased and decreased, respectively, in the dark condition. The proteins were mainly functionally grouped into cell organization, protein degradation/synthesis, and glycolysis. The highly abundant lactate/malate dehydrogenase proteins were decreased in flooding-stressed roots exposed to light, whereas the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme was increased in both light and dark conditions. Notably, however, specific enzyme assays revealed that the activities of these enzymes and biophoton emission were sharply increased after 3 days of flooding stress. This finding suggests that the source of biophoton emission in roots might involve the chemical excitation of electron or proton through enzymatic or non-enzymatic oxidation and reduction reactions. Moreover, the lysine ketoglutarate reductase/saccharopine dehydrogenase bifunctional enzyme may play important roles in responses in flooding stress of soybean under the light condition and as a contributing factor to biophoton emission. 相似文献
94.
Hideyuki Yamamoto Yoshiki Saitoh Setsuko Yasugawa Eishichi Miyamoto 《Journal of neurochemistry》1990,55(2):683-690
When the synaptosomal cytosol fraction from rat brain was chromatographed on a DEAE-cellulose column and assayed for protein phosphatases for τ factor and histone H1, two peaks of activities, termed peak 1 (major) and peak 2 (minor), were separated. Each peak was in a single form on Sephacryl S-300 column chromatography. Both peaks 1 and 2 dephosphorylated τ factor phosphorylated by Ca2+/calmodulin-dependent protein kinase II and the catalytic subunit of cyclic AMP-dependent protein kinase. The Km values were in the range of 0.42–0.84 μM for τ factor. There were no differences in kinetic properties of dephosphorylation between the substrates phosphorylated by the two kinases. The phosphatase activities did not depend on Ca2+, Mn2+, and Mg2+. Immunoprecipitation and immunoblotting analysis using polyclonal antibodies to the catalytic subunit of brain protein phosphatase 2A revealed that both protein phosphatases are the holoenzymic forms of protein phosphatase 2A. Aluminum chloride inhibited the activities of both peaks 1 and 2 with IC50 values of 40–60 μM. These results suggest that dephosphorylation of r factor in presynaptic nerve terminals is controlled mainly by protein phosphatase 2A and that the neurotoxic effect of aluminum seems to be related mostly to inhibition of dephosphorylation of τ factor 相似文献
95.
A homogeneous preparation of sepiapterin reductase, an enzyme involved in the biosynthesis of tetrahydrobiopterin, from rat erythrocytes was found to be responsible for the reduction with NADPH of various carbonyl compounds of non-pteridine derivatives including some vicinal dicarbonyl compounds which were reported in the previous paper (Katoh, S. and Sueoka, T. (1984) Biochem. Biophys. Res. Commun. 118, 859–866) in addition to the general substrate, sepiapterin (2-amino-4-hydroxy-6-lactoyl-7,8-dihydropteridine). The compounds sensitive as substrates of the enzyme were quinones, e.g., p-quinone and menadione; other vicinal dicarbonyls, e.g., methylglyoxal and phenylglyoxal; monoaldehydes, e.g., p-nitrobenzaldehyde; and monoketones, e.g., acetophenone, acetoin, propiophenone and benzylacetone. Rutin, dicoumarol, indomethacin, and ethacrynic acid inhibited the enzyme activity toward either a carbonyl compound of a non-pteridine derivative or sepiapterin as substrate. Sepiapterin reductase is quite similar to general aldo-keto reductases, especially to carbonyl reductase. 相似文献
96.
Genetic characterization of hemagglutinin protein of measles viruses in Hokkaido district,Japan, 2006–2015
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Masahiro Miyoshi Rika Komagome Hiroki Yamaguchi Setsuko Ishida Hideki Nagano Motohiko Okano 《Microbiology and immunology》2018,62(6):411-417
97.
Akira Ota †Satoshi Yoshida ‡Takahide Nomura ‡Shigeru Matsui ‡Yasumichi Hagino §Kazuo Umezawa Setsuko Katoh † Toshiharu Nagatsu 《Journal of neurochemistry》1996,67(6):2540-2548
Abstract: We investigated for the first time the effect of lipopolysaccharide and the signal transduction pathway on the biosynthesis of tetrahydrobiopterin [(6 R - l - erythro -1',2'-dihydroxypropyl)-2-amino-4-hydroxy-5,6,7,8-tetrahydropteridine], the cofactor for the enzymatic hydroxylation of the aromatic amino acids, in the murine neuroblastoma cell line N1E-115, which synthesizes tetrahydrobiopterin constitutively. Activation of N1E-115 cells with 1 µg/ml lipopolysaccharide resulted in statistically significant increases in both intracellular tetrahydrobiopterin contents and the activity ( V max ) of GTP cyclohydrolase I, a rate-limiting enzyme in tetrahydrobiopterin de novo biosynthesis. Following simultaneous addition of the inhibitors of protein tyrosine kinases and GTP-binding proteins into serum-free culture media with lipopolysaccharide, we analyzed the transduction pathway of lipopolysaccharide signal toward the tetrahydrobiopterin biosynthetic system in N1E-115 cells. Our data indicate the following conclusions: (a) Protein tyrosine kinase systems are involved in mediating lipopolysaccharide signal to tetrahydrobiopterin production, and (b) there may be a cross-talk between GTP-binding protein and the protein tyrosine kinase system in mediating lipopolysaccharide signal. These observations suggest that a neuronal cell such as N1E-115, which barely expresses CD14 on its cell surface, responds to lipopolysaccharide like macrophages and monocytes in the absence of soluble CD14. 相似文献
98.
Yoshiyuki Tohno Masako Utsumi Setsuko Tohno Takeshi Minami Yuko Okazaki Yumi Moriwake Fumio Nishiwaki Masa-oki Yamada Tadashi Fujii Yoshinori takakura 《Biological trace element research》1997,60(1-2):81-90
To elucidate age-related change of mineral contents in human bones, the mineral content and density of human calcanei were
determined by inductively coupled plasma atomic emission spectrometry and dual-energy X-ray absorptiometry. Calcanei were
removed from 27 subjects (17 men and 10 women) who died in the age range from 40–98 yr old.
Both the inductively coupled plasma emission spectrometry and dual-energy X-ray absorptiometry indicated that there were agedependent
decreases of the mineral contents and density in the men’s calcaneus in the age range from 40–98 yr, but not in the women’s
calcaneus in the age range from 42–87 yr. It was also found that the calcanean masses of the men and women remained constant
within the same age range until 98 yr. 相似文献
99.
Toshiya Imajo Hiroyuki Kawachi Haruyuki Atomi Shin-ichi Sanuki Setsuko Yamamoto Mitsuyoshi Ueda A. Tanaka 《Archives of microbiology》1997,168(5):389-395
Although peroxisomal localization of NADP-linked isocitrate dehydrogenase (Idp) was first demonstrated in Candida tropicalis, the mitochondrial isozyme has not been found in this yeast. Here we report that the presence of mitochondrial Idp in the
yeast was demonstrated by screening for its gene with a DNA probe containing conserved sequences of Idps from various organisms.
The nucleotide sequence of the gene (CtIDP1) revealed a 1,290-bp open reading frame corresponding to a 430-amino-acid protein with a high similarity to previously reported
Idps. Overexpression of CtIDP1 in Saccharomyces cerevisiae gave a high intracellular Idp activity, and the purified recombinant Idp was shown to be a homodimer with a subunit molecular
mass of approximately 44 kDa, different from that of peroxisomal Idp (45 kDa) previously purified from C. tropicalis. Western blot analysis of the subcellular fractions from acetate-grown C. tropicalis with polyclonal antibodies raised against the recombinant CtIdp1 showed that the CtIdp1 in C. tropicalis was localized in mitochondria but not in peroxisomes. Similar levels of CtIDP1 mRNA and its protein product were detected in cells grown on glucose, acetate, and n-alkane, although a slight decrease was observed in n-alkane-grown cells. From these results, CtIdp1 was demonstrated to be mitochondrial Idp. The properties of mitochondrial
Idp and peroxisomal Idp isozymes were proven to be similar, but they were immunochemically distinct, suggesting the presence
of another gene responsible for peroxisomal Idp in C. tropicalis.
Received: 11 March 1997 / Accepted: 24 June 1997 相似文献
100.
Ryo Kubota Setsuko Noda Yimin Wang Shinsei Minoshima Shuichi Asakawa Jun Kudoh Yukihiko Mashima Yoshihisa Oguchi Nobuyoshi Shimizu 《Genomics》1997,41(3):360
We have isolated a human cDNA clone encoding a novel acidic protein of MW 55,000 that we designated “myocilin” since it has homology to myosin and is localized preferentially in the ciliary rootlet and basal body of the connecting cilium of photoreceptor cells. The deduced amino acid sequence of human myocilin showed significant homologies with nonmuscle myosin ofDictyostelium discoideumin the N-terminal region and also with olfactomedin of bullfrog in the C-terminal region. Myocilin contained a leucine zipper-like motif similar to that seen in kinectin and other cytoskeletal proteins. These findings suggest that myocilin is a novel cytoskeletal protein involved in the morphogenesis of ciliated neuroepithelium such as photoreceptor cells. The myocilin gene (MYOC) was mapped to human chromosome 1q23–q24 by fluorescencein situhybridization. 相似文献