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101.
102.
Fukuko Watanabe Toshie Ryota Yoshiharu Kobayashi Toshio Ogihara Yuichi Kumahara 《Steroids》1984,43(5):509-516
An enzyme immunoassay for serum 18-hydroxycorticosterone was established using alkaline phosphatase as a label. The antiserum for 18-hydroxycorticosterone was produced by immunization of rabbits with 18-hydroxycorticosterone 3-(O-carboxymethyl)oxime conjugated to bovine serum albumin. Sephadex LH-20 column chromatography was used to separate 18-hydroxycorticosterone from other steroids in serum samples. The minimal detectable amount of 18-hydroxycorticosterone was 50 pg/tube and the measurable range was from 5 to 1000 ng/dl when a 1.0 ml serum sample was used. Intra- and inter-assay coefficients of variance were 5.0% (n=6) and 5.8% (n=6), respectively. Four of 5 patients with aldosterone-producing adenoma had above-normal serum 18-hydroxycorticosterone levels. 相似文献
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Separation of novel phosphoproteins of Porphyromonas gingivalis using phosphate‐affinity chromatography
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Masashi Izumigawa Yoshiaki Hasegawa Ryota Ikai Toshi Horie Megumi Inomata Takeshi Into Noriyuki Kitai Fuminobu Yoshimura Yukitaka Murakami 《Microbiology and immunology》2016,60(10):702-707
Phosphorylation of serine, threonine and tyrosine is a central mechanism for regulating the structure and function of proteins in both eukaryotes and prokaryotes. However, the action of phosphorylated proteins present in Porphyromonas gingivalis, a major periodontopathogen, is not fully understood. Here, six novel phosphoproteins that possess metabolic activities were identified, namely PGN_0004, PGN_0375, PGN_0500, PGN_0724, PGN_0733 and PGN_0880, having been separated by phosphate‐affinity chromatography. The identified proteins were detectable by immunoblotting specific to phosphorylated Ser (P‐Ser), P‐Thr, and/or P‐Tyr. These results imply that novel phosphorylated proteins might play an important role for regulation of metabolism in P. gingivalis. 相似文献
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The principal insecticidal compounds from the herbal medicines Saishin, the root of Asarum sieboldii Miquel, and Sekishōkon, the rhizome of Acorus gramineus Soland, were isolated by successive silica gel column chromatography and high performance liquid chromatography. The active components, which work against larvae of the cigarette beetle, Lasioderma serricorne (F.), were identified as methyleugenol (4-allyl-1,2-dimethoxybenzene) and β-asarone {1,2,4-trimethoxy-5-[(Z)-prop-1-enyl]benzene} by gas chromatography and gas chromatography/mass spectrometry analyses. These two compounds share some structural features, such as a benzene ring with o-dimethoxy groups and a propenyl group in the opposite position. Consequently, the insecticidal activities of 20 structurally related compounds were tested to evaluate their structure–activity relationship. We found myristicin (5-allyl-1-methoxy-2,3-methylenedioxybenzene) exhibited comparable insecticidal activity to methyleugenol and β-asarone, but the other tested compounds were less active. The lack of insecticidal activity of compounds with a hydrogen, hydroxy, or acetoxy substituent in place of one methoxy group indicates that o-dimethoxy groups are essential for insecticidal activity. The position and configuration of a double bond in the propenyl side chain affected the toxicity, but there was a lack of consistency in the structure–activity relationship for this. 相似文献
108.
Tomoyuki Bando Setsuko Fujita Naoko Nagano Soichiro Yoshikawa Yoshinori Yamanishi Masashi Minami Hajime Karasuyama 《Biochemistry and Biophysics Reports》2017
Basophils have been erroneously considered as minor relatives of mast cells, due to some phenotypic similarity between them. While recent studies have revealed non-redundant roles for basophils in various immune responses, basophil-derived effector molecules, including lipid mediators, remain poorly characterized, compared to mast cell-derived ones. Here we analyzed and compared eicosanoids produced by mouse basophils and mast cells when stimulated with IgE plus allergens. The production of 5-LOX metabolites such as LTB4 and 5-HETE was detected as early as 0.5 h post-stimulation in both cell types, even though their amounts were much smaller in basophils than in mast cells. In contrast, basophils and mast cells showed distinct time course in the production of COX metabolites, including PGD2, PGE2 and 11-HETE. Their production by mast cells was detected at both 0.5 and 6 h post-stimulation while that by basophils was detectable only at 6 h. Of note, mast cells showed 8–9 times higher levels of COX-1 than did basophils at the resting status. In contrast to unaltered COX-1 expression with or without stimulation, COX-2 expression was up-regulated in both cell types upon activation. Importantly, when activated, basophils expressed 4–5 times higher levels of COX-2 than did mast cells. In accordance with these findings, the late-phase production of the COX metabolites by basophils was completely ablated by COX-2 inhibitor whereas the early-phase production by mast cells was blocked by COX-1 but not COX-2 inhibitor. Thus, the production of COX metabolites is differentially regulated by COX-1 and COX-2 in basophils and mast cells. 相似文献
109.
Akagi R Kanehisa H Kawakami Y Fukunaga T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(1):82-87
The present study aimed i) to establish an index of muscle cross-sectional area (CSA) based on muscle thickness and circumference through a comparison with muscle CSA determined by magnetic resonance imaging (MRI), and ii) to examine the relationships between muscle strength and the index determined at rest and during the maximal isometric contraction. The muscle CSA of elbow flexors at 60% of the upper arm length (CSA60) and the maximal CSA of elbow flexors (CSAmax) were measured using MRI in 26 men and 8 women. The muscle thickness (MT) of elbow flexors and the circumference (C) of upper arm at 60% of the upper arm length were measured using ultrasonography and anthropometry, respectively, in 29 men and 9 women. The measurements of MT and C were performed in the resting (MT(r) and C(r)) and contracted condition (MT(m) and C(m)), where the subjects performed maximal voluntary contraction (MVC) of isometric elbow joint flexion. The torque developed during MVC was converted into the muscle force (F) of elbow flexors. The MT(r) x C(r) was significantly correlated both with CSA60 and CSAmax (P < 0.001). The F was significantly correlated with MT(m) x C(m) (r = 0.847, P < 0.001) and MT(r) x C(r) (r = 0.839, P < 0.001). However, stepwise multiple regression analysis selected only MT(m) x C(m) as a significant contributor for estimating F. The present study indicates that MT x C reflects muscle CSA, and can be an index for assessing muscle CSA. In addition, the findings obtained here showed a possibility that MT x C during MVC is more closely related to F than that at rest. 相似文献
110.
Onda K Shiraki R Ogiyama T Yokoyama K Momose K Katayama N Orita M Yamaguchi T Furutani M Hamada N Takeuchi M Okada M Ohta M Tsukamoto S 《Bioorganic & medicinal chemistry》2008,16(23):10001-10012
As a result of the various N-bicyclo-5-chloro-1H-indole-2-carboxamide derivatives with a hydroxy moiety synthesized in an effort to discover novel glycogen phosphorylase (GP) inhibitors, 5-chloro-N-(5-hydroxy-5,6,7,8-tetrahydronaphthalen-2-yl)-1H-indole-2-carboxamide (5b) was found to have potent inhibitory activity. The introduction of fluorine atoms both at a position adjacent to the hydroxy group and in the central benzene moiety lead to the optically active derivative 5-chloro-N-[(5R)-1,3,6,6-tetrafluoro-5-hydroxy-5,6,7,8-tetrahydronaphthalen-2-yl]-1H-indole-2-carboxamide (25e(alpha), which was the most potent compound in this series (IC(50)=0.020microM). This compound inhibited glucagon-induced glucose output in cultured primary hepatocytes with an IC(50) value of 0.69microM, and showed oral hypoglycemic activity in diabetic db/db mice at 10mg/kg. Compound 25e(alpha) also had an excellent pharmacokinetic profile, with high oral bioavailability and a long plasma half-life, in male SD rats. The binding mode of 25e(alpha) to this molecule and the role of fluorine atoms in that binding were speculated in an enzyme docking study. 相似文献