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11.
A fusion protein of metapyrocatechase and protein A was genetically produced for demonstration of effective conjugation of an enzyme with a binding protein employed in enzyme immunoassay. Plasmid pMPRA3, constructed by inserting the protein A gene into a plasmid pMK12 vector derived directly from the structural gene of metapyrocatechase, was expressed in Escherichia coli. The resulting fusion protein was shown to have promising properties for use in enzyme immunoassays due to the specific binding of the protein A moiety to the Fc portion of immunoglobulin G and to the high amplification of enzyme. Bovine serum albumin, a model antigen, was successfully determined in the concentration range from 1 x 10(-3) to 1 x 10(-7) g/ml. 相似文献
12.
Y Ikariyama H Kunoh M Aizawa 《Biochemical and biophysical research communications》1985,128(2):987-992
Aromatic hydrocarbon such as pyrene capable of generating electrochemical luminescence was employed as a label of immunoassay. Pyrene labeled antigen generated luminescence upon electrolytic reduction, while the luminescence decreased remarkably in the presence of antibody. The labeled antigen (constant) and free antigen were competitively reacted to the constant amount of antibody. The luminescence was correlated to the antigen concentration as little as 10(-6)M antigen. The proposed method is a very unique immunochemical technique which requires no BF separation. 相似文献
13.
Masakazu Goto Chisato Ito Mohammed Sani Yahaya Yoshihito Wakai Shiro Asano Yukari Oka 《Marine and Freshwater Behaviour and Physiology》2013,45(2):99-107
The number of microorganisms in the hindgut of dugongs (Dugong dugon) were estimated and their in vitro volatile fatty acid (VFA) production and degradation of eelgrass measured. Scanning electron microscopy showed that some rod bacteria attached to the surface of plant tissue degraded and eroded the cell walls. Number of starch-, lactate-, cellobiose-, pectin-, xylan- and cellulose-utilizing bacteria, sulfate-reducing bacteria and methane-producing bacteria were estimated at 109 ~ 1010 colony forming units g?1. Microorganisms degraded the cellulose and noncellulolytic components of the eelgrass, and about 47.3% of dry matter was degraded after 36?h in vitro incubation. The total VFA concentration was 10.5?mmol?dL?1 at 36?h incubation, which included 55.7?mol% acetate, 18.0?mol% n-butyrate and 15.1?mol% propionate. The gas composition of in vitro fermentation was 68.4% carbon dioxide, 22.2% methane and 9.4% hydrogen. 相似文献
14.
Yuji Sumita Michiyo Shirato Yoshihito Ueno Akira Matsuda Satoshi Shuto 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):175-187
Abstract The synthesis of cyclic ADP-carbocyclic-ribose (2), as a stable mimic for cyclic ADP-ribose, was investigated. Construction of the 18-membered backbone structure was successfully achieved by condensation of the two phosphate groups of 19, possibly due to restriction of the conformation of the substrate in a syn-form using an 8-chloro substituent at the adenine moiety. SN2 reactions between an optically active carbocyclic unit 8, which was constructed by a previously developed method, and 8-bromo-N 6-trichloroacetyl-2′,3′-O-isopropylideneadenosine 9c gave N-1-carbocyclic derivative, which was deprotected to give 5′,5′-diol derivatives 18. When 18 was treated with POCl3 in PO(OEt)3, the bromo group at the 8-position was replaced to give N-1-carbocyclic-8-chloroadenosine 5′,5′-diphosphate derivative 19 in 43% yield. Treatment of 19 with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride gave the desired intramolecular condensation product 20 in 10% yield. This is the first chemical construction of the 18-membered backbone structure containing an intramolecular pyrophosphate linkage of a cADPR-related compound with an adenine base. 相似文献
15.
Yoshiaki Kitamura Yuki Masegi Shunsuke Ogawa Remi Nakashima Yukihiro Akao Yoshihito Ueno Yukio Kitade 《Bioorganic & medicinal chemistry》2013,21(15):4494-4501
We have developed chemically modified siRNAs and miRNAs bearing urea/thiourea-bridged aromatic compounds at their 3′-end for RNAi therapy. Chemically modified RNAs possessing urea/thiourea-bridged aromatic compounds instead of naturally occurring dinucleotides at the 3′-overhang region were easily prepared in good yields and were more resistant to nucleolytic hydrolysis than unmodified RNA. siRNAs containing urea or thiourea derivatives showed the desired knockdown effect. Furthermore, modified miR-143 duplexes carrying the urea/thiourea compounds in the 3′-end of each strand were able to inhibit the growth of human bladder cancer T24 cells. 相似文献
16.
Yoshihito Suzuki Isomaro Yamaguchi Takao Yokota Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(12):3133-3138
From the pollen of Zea mays, three brassinosteroids, castasterone, typhasterol and teasterone, were identified by GC/MS and/or 1H NMR. Their concentrations in the pollen were shown by GC/SIM to be about 120 μg/kg fr.wt. (castasterone), 6.6 μg/kg fr.wt. (typhasterol) and 4.1 μg/kg fr.wt. (teasterone). It was also found that the anther contained a fairly large amount of brassinosteroids by a bioassay. 相似文献
17.
Hiroyoshi Yamauchi Masashi Bando Tomohisa Baba Kensuke Kataoka Yoshihito Yamada Hiroshi Yamamoto Atsushi Miyamoto Soichiro Ikushima Takeshi Johkoh Fumikazu Sakai Yasuhiro Terasaki Akira Hebisawa Yoshinori Kawabata Yukihiko Sugiyama Takashi Ogura 《PloS one》2016,11(11)
Some patients with idiopathic pulmonary fibrosis (IPF) do not have honeycombing on high-resolution computed tomography (HRCT) at their initial evaluation. The clinical course and sequential changes in HRCT findings in these patients are not fully understood. We reviewed the cases of 43 patients with IPF without honeycombing on initial HRCT from institutions throughout Japan. All patients were diagnosed with IPF based on a surgical lung biopsy. Multidisciplinary discussions were held five times between 2011 and 2014, to exclude alternative etiologies. We evaluated the sequential changes in HRCT findings in 30 patients with IPF. We classified these 30 patients into three groups based on their HRCT patterns and clarified the clinical characteristics and prognosis among the groups. The patterns of all 30 patients on initial HRCT corresponded to a possible usual interstitial pneumonia (UIP) pattern which was described in the 2011 International Statement. On long-term follow-up (71.0±38.7 standard deviation [SD] months), honeycombing was seen in 16 patients (53%, the HoneyCo group); traction bronchiectasis or cysts without honeycombing was observed in 12 patients (40%, the NoHoneyCo group), and two patients showed no interval change (7%, the NoChange group) on HRCT. The mean survival periods of the HoneyCo and NoHoneyCo groups were 67.1 and 61.2 months, respectively (p = 0.76). There are some patients with IPF whose conditions chronically progress without honeycombing on HRCT. The appearance of honeycombing on HRCT during the follow-up might not be related to prognosis. 相似文献
18.
Ehlinger Claire Dartevelle Pauline Zaet Abdurraouf Kurashige Yoshihito Haïkel Youssef Metz-Boutigue Marie-Hélène Marban Céline 《International journal of peptide research and therapeutics》2019,25(4):1679-1687
International Journal of Peptide Research and Therapeutics - The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only... 相似文献
19.
Akash Chandela Taeko Watanabe Kenji Yamagishi Yoshihito Ueno 《Bioorganic & medicinal chemistry》2019,27(7):1341-1349
With the aim to create a small interfering RNA (siRNA) with enhanced activity and resistance to nuclease degradation, we synthesized and evaluated the properties of the following siRNAs containing haloalkyl β-d-ribofuranosides at their 3′-dangling ends: 2,2,2-trifluoroethyl β-d-ribofuranoside, 2,2,2-trichloroethyl β-d-ribofuranoside and 2,2,2-tribromoethyl β-d-ribofuranoside. The gene silencing activities of the modified siRNAs were investigated through a dual luciferase reporter assay using HeLa cells. The highest silencing activity was observed for the trichloroethyl analog modified siRNA, which was closely followed by the trifluoroethyl and tribromoethyl analogs. The modified siRNAs were found to show increased binding affinity towards the Piwi-Argonaute-Zwille (PAZ) domain protein based on computational analysis and an experimental study. Furthermore, the RNAs modified with the analogs at their 3′-ends exhibited improved resistance to hydrolysis by a 3′-exonuclease. 相似文献
20.
Kuwata H Fujimoto C Yoda E Shimbara S Nakatani Y Hara S Murakami M Kudo I 《The Journal of biological chemistry》2007,282(28):20124-20132
Group IIA secretory phospholipase A(2) (sPLA(2)-IIA) is a prototypic sPLA(2) enzyme that may play roles in modification of eicosanoid biosynthesis as well as antibacterial defense. In several cell types, inducible expression of sPLA(2) by pro-inflammatory stimuli is attenuated by group IVA cytosolic PLA(2) (cPLA(2)alpha) inhibitors such as arachidonyl trifluoromethyl ketone, leading to the proposal that prior activation of cPLA(2)alpha is required for de novo induction of sPLA(2). However, because of the broad specificity of several cPLA(2)alpha inhibitors used so far, a more comprehensive approach is needed to evaluate the relevance of this ambiguous pathway. Here, we provide evidence that the induction of sPLA(2)-IIA by pro-inflammatory stimuli requires group VIB calcium-independent PLA(2) (iPLA(2)gamma), rather than cPLA(2)alpha, in rat fibroblastic 3Y1 cells. Results with small interfering RNA unexpectedly showed that the cytokine induction of sPLA(2)-IIA in cPLA(2)alpha knockdown cells, in which cPLA(2)alpha protein was undetectable, was similar to that in replicate control cells. By contrast, knockdown of iPLA(2)gamma, another arachidonyl trifluoromethyl ketone-sensitive intracellular PLA(2), markedly reduced the cytokine-induced expression of sPLA(2)-IIA. Supporting this finding, the R-enantiomer of bromoenol lactone, an iPLA(2)gamma inhibitor, suppressed the cytokine-induced sPLA(2)-IIA expression, whereas (S)-bromoenol lactone, an iPLA(2)beta inhibitor, failed to do so. Moreover, lipopolysaccharide-stimulated sPLA(2)-IIA expression was also abolished by knockdown of iPLA(2)gamma. These findings open new insight into a novel regulatory role of iPLA(2)gamma in stimulus-coupled sPLA(2)-IIA expression. 相似文献