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41.
Pattaporn Jaikhan Benjaporn Buranrat Yukihiro Itoh Jiranan Chotitumnavee Takashi Kurohara Takayoshi Suzuki 《Bioorganic & medicinal chemistry letters》2019,29(10):1173-1176
Fe(II)/α-ketoglutarate-dependent lysine demethylases (KDMs) are attractive drug targets for several diseases including cancer. In this study, we designed and screened ortho-substituted anilides that are expected to function as Fe(II) chelators, and identified ortho-hydroxy anilide as a novel scaffold for KDM5A inhibitors. Treatment of human lung cancer A549 cells with a prodrug form of 4-carboxy-2-hydroxy-formanilide (9c) increased trimethylated lysine 4 on histone H3 level, suggesting KDM5 inhibition in the cells. 相似文献
42.
Nijikken Y Tsukada T Igarashi K Samejima M Wakagi T Shoun H Fushinobu S 《FEBS letters》2007,581(7):1514-1520
The white-rot fungus Phanerochaete chrysosporium has two intracellular beta-glucosidases (BGL1A and BGL1B) belonging to glycoside hydrolase (GH) family 1. BGL1B effectively hydrolyzes cellobiose and cellobionolactone, but BGL1A does not. We have determined the crystal structure of BGL1A in substrate-free and gluconolactone complexed forms. The overall structure and the characteristic of subsite -1 (glycone site) were similar to those of other known GH1 enzymes. The loop regions covering on the (beta/alpha)(8) barrel was significantly deviated, and they form a unique subsite +1 (aglycone site) of BGL1A. 相似文献
43.
Role of MAPK phosphatase-1 in the induction of monocyte chemoattractant protein-1 during the course of adipocyte hypertrophy 总被引:2,自引:0,他引:2
Ito A Suganami T Miyamoto Y Yoshimasa Y Takeya M Kamei Y Ogawa Y 《The Journal of biological chemistry》2007,282(35):25445-25452
Monocyte chemoattractant protein-1 (MCP-1), an important chemokine whose expression is increased during the course of obesity, plays a role in macrophage infiltration into obese adipose tissue. This study was designed to elucidate the role of mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1) in the induction of MCP-1 during the course of adipocyte hypertrophy. We examined the time course of MKP-1 and MCP-1 mRNA expression and extracellular signal-regulated kinase (ERK) phosphorylation in the adipose tissue from mice rendered mildly obese by a short term high fat diet. We also studied the role of MKP-1 in the induction of MCP-1 in 3T3-L1 adipocytes during the course of adipocyte hypertrophy. MCP-1 mRNA expression was increased, followed by ERK activation and down-regulation of MKP-1, an inducible dual specificity phosphatase to inactivate ERK, in the adipose tissue at the early stage of obesity induced by a short term high fat diet, when macrophages are not infiltrated. Down-regulation of MKP-1 preceded ERK activation and increased production of MCP-1 in 3T3-L1 adipocytes in vitro during the course of adipocyte hypertrophy. Adenovirus-mediated restoration of MKP-1 in hypertrophied 3T3-L1 adipocytes reduced the otherwise increased ERK phosphorylation, thereby leading to the significant reduction of MCP-1 mRNA expression. This study provides evidence that the down-regulation of MKP-1 is critical for increased production of MCP-1 during the course of adipocyte hypertrophy. 相似文献
44.
We investigated the photoperiodic response of serotonin- and galanin (GA)- immunoreactive (ir) cells in the paraventricular organ (PVO) and infundibular nucleus (IF) of the Japanese quail and the interaction of these cells with gonadotropin-releasing hormone (GnRH)-ir neurons in the hypothalamus. Serotonin-ir cells were located in series from the PVO to the IF, and were connected with each other. The number of serotonin-ir cells differed significantly between light and dark phases on the short days (SD), but did not differ between light and dark phases on long days (LD). GA-ir cells were also found in the PVO and IF. The number of GA-ir cells under SD conditions was significantly greater than under LD conditions but did not change diurnally. Both serotonin-ir and GA-ir fibers ran along the GnRH-ir cells in the nucleus commissurae pallii. Serotonin-ir and GA-ir fibers were connected with the GnRH-ir fibers in the external layer of the median eminence (ME). We confirmed that GA-ir fibers were closely associated with serotonin-ir neurons in the PVO and IF. GA-ir neurons have at least 2 routes of regulating GnRH neurons directly, and indirectly via the serotonin-ir cells in the PVO and IF. 相似文献
45.
BACKGROUND AND AIMS: Betula ermanii, B. maximowicziana and B. platyphylla var. japonica have heterophyllous leaves (i.e. early leaves and late leaves) and are typical pioneer species in northern Japan. Chemical and physical defences against herbivores in early and late leaves of these species were studied. METHODS: Two-year-old seedlings were grown under full sunlight in a single growing season. Three-week-old leaves of each seedling were harvested three times (May, July and October). Total phenolics and condensed tannin content were determined for chemical defence and leaf toughness and trichome density were assessed for physical defence. Defoliation of early leaves in May was also performed to study the contribution of early leaves to subsequent growth. KEY RESULTS: Chemical and physical defences were greater in early than late leaves in B. platyphylla and B. ermanii, whereas the reverse was true in B. maximowicziana. In contrast to its weak chemical defences, the trichome density in B. maximowicziana was very high. In B. platyphylla and B. ermanii, the relative growth rates (RGR) were greater early in the growing season. Negative effects on growth of removal of early leaves were significant only in B. platyphylla. CONCLUSIONS: B. platyphylla and B. ermanii invest in defence in early rather than late leaves, since early leaves are crucial to subsequent growth. In contrast, B. maximowicziana more strongly defends its late leaves, since its RGR is maintained at the same level throughout the growing season. 相似文献
46.
47.
Takeshi?IzutaEmail author Taeko?Yamaoka Tatsuro?Nakaji Tetsushi?Yonekura Masaaki?Yokoyama Ryo?Funada Takayoshi?Koike Tsumugu?Totsuka 《Trees - Structure and Function》2004,18(6):677-685
To obtain basic information for evaluating critical loads of acid deposition for protecting Japanese beech forests, growth, net photosynthesis and leaf nutrient status of Fagus crenata seedlings grown for two growing seasons in brown forest soil acidified with H2SO4 or HNO3 solution were investigated. The whole-plant dry mass of the seedlings grown in the soil acidified by the addition of H2SO4 or HNO3 solution was significantly less than that of the seedlings grown in the control soil not supplemented with H+ as H2SO4 or HNO3 solution. However, the degrees of reduction in the whole-plant dry mass and net photosynthetic rate of the seedlings grown in the soil acidified by the addition of H+ as H2SO4 solution at 100 mg l–1 on the basis of air-dried soil volume (S-100 treatment) were greater than those of the seedlings grown in the soil acidified by the addition of H+ as HNO3 solution at 100 mg l–1 (N-100 treatment). The concentrations of Al and Mn in the leaves of the seedlings grown in the S-100 treatment were significantly higher than those in the N-100 treatment. A positive correlation was obtained between the molar ratio of (Ca+Mg+K)/(Al+Mn) in the soil solution and the relative whole-plant dry mass of the seedlings grown in the acidified soils to that of the seedlings grown in the control soil. Based on the results, we concluded that the negative effects of soil acidification due to sulfate deposition are greater than those of soil acidification due to nitrate deposition on growth, net photosynthesis and leaf nutrient status of F. crenata, and that the molar ratio of (Ca+Mg+K)/(Al+Mn) in soil solution is a suitable soil parameter for evaluating critical loads of acid deposition in efforts to protect F. crenata forests in Japan. 相似文献
48.
49.
Kitabayashi T Demura S Noda M Yamada T 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2004,23(4):111-118
This study aimed to examine gender differences in 4 body-sway factors of the center of foot pressure (CFP) during a static upright posture and the influence of alcohol intake on them. Four body-sway factors were interpreted in previous studies using factor analysis (the principal factor method and oblique solution by promax-rotation) on 220 healthy young males and females as follows; unit time sway, front-back sway, left-right sway and high frequency band power. The CFP measurement for 1 min was carried out twice with 1 min rest. The measurements of blood pressure, heart rate, whole body reaction time, standing on one leg with eyes closed, and CFP were carried out before and after the alcohol intake using 11 healthy young males and females. The measurement device used was an Anima's stabilometer G5500. The data sampling frequency was 20 Hz. Reliability of 4 body-sway factors was very high. Significant gender differences were found in the left-right sway and the high frequency band power factors, but the influence on body-sway is, as a whole, can be disregarded. These four sway factors can determine the influence of alcohol intake as efficient as 32 sway parameters. 相似文献
50.
Preparation of Escherichia coli cell extract for highly productive cell-free protein expression 总被引:2,自引:0,他引:2
Kigawa T Yabuki T Matsuda N Matsuda T Nakajima R Tanaka A Yokoyama S 《Journal of structural and functional genomics》2004,5(1-2):63-68
As structural genomics and proteomics research has become popular, the importance of cell-free protein synthesis systems has been realized for high-throughput expression. Our group has established a high-throughput pipeline for protein sample preparation for structural genomics and proteomics by using cell-free protein synthesis. Among the many procedures for cell-free protein synthesis, the preparation of the cell extract is a crucial step to establish a highly efficient and reproducible workflow. In this article, we describe a detailed protocol for E. coli cell extract preparation for cell-free protein synthesis, which we have developed and routinely use. The cell extract prepared according to this protocol is used for many of our cell-free synthesis applications, including high-throughput protein expression using PCR-amplified templates and large-scale protein production for structure determinations. 相似文献