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91.
92.
Tadashi Shimamura Satoe Iijima Mitsuhiro Hirayama Masato Iwashita Shigeru Akiyama Yuichi Takaku Sakae Yumoto 《Journal of trace elements in medicine and biology》2013,27(4):286-294
The concentrations of 22 major and trace elements in livers from rats aging from 5 to 113 weeks old were determined. The rats investigated were the same rats previously reported with respect to 29 elements in bones (femur) and 26 elements in kidneys. The samples were decomposed with high-purity nitric acid and hydrogen peroxide. Seven elements (Na, Mg, P, K, Ca, Fe and Zn) were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES), and 15 elements (Mn, Co, Cu, As, Se, Rb, Sr, Mo, Cd, Sn, Sb, Cs, Ba, Pb and Bi) were determined by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of variance (ANOVA) for age variations indicated that the concentrations of many elements, such as Mg, P, K, Mn, Fe, Cu, Zn, Sr, Mo and Cd, were almost constant across the ages of the rats with the exception of 5 weeks old (p > 0.05). Arsenic, Pb and Bi showed significant increasing trends, while Na and Co showed decreasing trends (p < 0.01). Selenium showed a decreasing trend except at the initial stage of 5–9 weeks old. Calcium, Rb, Sn, Sb, Cs and Ba showed significant age-related variations, but their patterns were not monotonic. The liver clearly contrasts with the kidneys, in which many elements showed significant age-related variations with increasing trends. The concentration ranges of Mg, P, K, Mn, Cu, Zn, and Mo were controlled within 15% across all ages of rats. The homeostasis of the aforementioned elements may be well established in the liver. The toxic elements, such as Cd, Pb and Bi, showed a narrow concentration range among age-matched rats. 相似文献
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Haruhiko Machida Akira Kuninaka Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(8):1129-1135
The mechanism whereby Escherichia coli K12 accumulates orotic acid in culture fluid was studied. Pyrimidine compounds were incorporated effectively into cells of E. coli K12, stimulated the growth, and depressed the accumulation; while purine compounds were not so much consumed by the microorganism for its growth, and affected the accumulation to a lesser extent. On the other hand, E. coli B unable to accumulate orotic acid utilized less effectively pyrimidine compounds for its growth than strain K12.It is supposed, therefore, that in the de novo pathway for pyrimidine synthesis in E. coli K12 the step from orotic acid to 5′-UMP is genetically depressed so that orotic acid is accumulated when pyrimidine compounds, that would cause a feedback inhibition of orotic acid synthesis upon incorporation, are not supplemented. 相似文献
96.
Ryushi Kawakami Haruhiko Sakuraba Toshihisa Ohshima 《Bioscience, biotechnology, and biochemistry》2013,77(12):2045-2050
We previously found a very large NAD-dependent glutamate dehydrogenase with approximately 170?kDa subunit from Janthinobacterium lividum (Jl-GDH) and predicted that GDH reaction occurred in the central domain of the subunit. To gain further insights into the role of the central domain, several single point mutations were introduced. The enzyme activity was completely lost in all single mutants of R784A, K810A, K820A, D885A, and S1142A. Because, in sequence alignment analysis, these residues corresponded to the residues responsible for glutamate binding in well-known small GDH with approximately 50?kDa subunit, very large GDH and well-known small GDH may share the same catalytic mechanism. In addition, we demonstrated that C1141, one of the three cysteine residues in the central domain, was responsible for the inhibition of enzyme activity by HgCl2, and HgCl2 functioned as an activating compound for a C1141T mutant. At low concentrations, moreover, HgCl2 was found to function as an activating compound for a wild-type Jl-GDH. This suggests that the mechanism for the activation is entirely different from that for the inhibition. 相似文献
97.
Fumio Sugawara Haruhiko Nakayama Gary A. Strobel Tomoya Ogawa 《Bioscience, biotechnology, and biochemistry》2013,77(9):2261-2271
The stereoselective synthesis of 1- and 2-O-α-d-cellotriosyl-3-deoxy-2(R)- and 2(S)-glycerols, which determined the structure of rhynchosporoside produced by Rhynchosporium secalis, and their phytotoxicity toward the host plant (Hordeum vulgare) are described in detail. 相似文献
98.
Tadashi Mori Masafumi Hidaka Hiroko Ikuji Ibuki Yoshizawa Haruhiko Toyohara Toru Okuda 《Bioscience, biotechnology, and biochemistry》2013,77(5):832-838
The peptidyl prolyl cis/trans isomerase Pin1 enhances the uptake of triglycerides and the differentiation of fibroblasts into adipose cells in response to insulin stimulation. Pin1 downregulation could be a potential approach to prevent and treat obesity-related disorders. In order to identify an inhibitor of Pin1 that exhibited minimal cytotoxicity, we established a high-throughput screen for Pin1 inhibitors and used this method to identify an inhibitor from 1,056 crude fractions of two natural product libraries. The candidate, a phlorotannin called 974-B, was isolated from the seaweed, Ecklonia kurome. 974-B inhibited the differentiation of mouse embryonic fibroblasts and 3T3-L1 cells into adipose cells without inducing cytotoxicity. We discovered the Pin1 inhibitor, 974-B, from the seaweed, E. kurome, and showed that it blocks the differentiation of fibroblasts into adipose cells, suggesting that 974-B could be a lead drug candidate for obesity-related disorders. 相似文献
99.
Ryosuke Tateishi Shuichiro Shiina Masaaki Akahane Jiro Sato Yuji Kondo Ryota Masuzaki Hayato Nakagawa Yoshinari Asaoka Tadashi Goto Kuni Otomo Masao Omata Haruhiko Yoshida Kazuhiko Koike 《PloS one》2013,8(4)
Background
In the treatment of hepatocellular carcinoma (HCC), hepatic resection has the advantage over radiofrequency ablation (RFA) in terms of systematic removal of a hepatic segment.Methods
We enrolled 303 consecutive patients of a single naïve HCC that had been treated by RFA at The University of Tokyo Hospital from 1999 to 2004. Recurrence was categorized as either intra- or extra-subsegmental as according to the Couinaud''s segment of the original nodule. To assess the relationship between the subsegments of the original and recurrent nodules, we calculated the kappa coefficient. We assessed the risk factors for intra- and extra-subsegmental recurrence independently using univariate and multivariate Cox proportional hazard regression. We also assessed the impact of the mode of recurrence on the survival outcome.Results
During the follow-up period, 201 patients in our cohort showed tumor recurrence distributed in a total of 340 subsegments. Recurrence was categorized as exclusively intra-subsegmental, exclusively extra-subsegmental, and simultaneously intra- and extra-subsegmental in 40 (20%), 110 (55%), and 51 (25%) patients, respectively. The kappa coefficient was measured at 0.135 (95% CI, 0.079–0.190; P<0.001). Multivariate analysis revealed that of the tumor size, AFP value and platelet count were all risk factors for both intra- and extra-subsegmental recurrence. Of the patients in whom recurrent HCC was found to be exclusively intra-subsegmental, extra-subsegmental, and simultaneously intra- and extra-subsegmental, 37 (92.5%), 99 (90.8%) and 42 (82.3%), respectively, were treated using RFA. The survival outcomes after recurrence were similar between patients with an exclusively intra- or extra-subsegmental recurrence.Conclusions
The effectiveness of systematic subsegmentectomy may be limited in the patients with both HCC and chronic liver disease who frequently undergo multi-focal tumor recurrence. 相似文献100.
Noriyoshi Watanabe Satoshi Morimoto Takeo Fujiwara Tomo Suzuki Kosuke Taniguchi Takashi Ando Tadashi Kimura Haruhiko Sago Atsuhiro Ichihara 《PloS one》2013,8(3)