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81.
Attachment of a myristoyl group to NH(2)-terminus of a nascent protein among protein post-translational modification (PTM) is called myristoylation. The myristate moiety of proteins plays an important role for their biological functions, such as regulation of membrane binding (HIV-1 Gag) and enzyme activity (AMPK). Several predictors based on protein sequences alone are hitherto proposed. However, they produce a great number of false positive and false negative predictions; or they cannot be used for general purpose (i.e., taxon-specific); or threshold values of the decision rule of predictors need to be selected with cautiousness. Here, we present novel and taxon-free predictors based on protein primary structure. To identify myristoylated proteins accurately, we employ a widely used machinelearning algorithm, support vector machine (SVM). A series of SVM predictors are developed in the present study where various scales representing physicochemical and biological properties of amino acids (from the AAindex database) are used for numerical transformation of protein sequences. Of the predictors, the top ten achieve accuracies of >98% (the average value is 98.34%), and also the area under the ROC curve (AUC) values of >0.98. Compared with those of previous studies, the prediction accuracies are improved by about 3 to 4%. 相似文献
82.
Monotherapy with a novel intervenolin derivative,AS‐1934, is an effective treatment for Helicobacter pylori infection 下载免费PDF全文
83.
Tohru Nakashizuka 《Ecological Research》1988,3(1):21-35
Seedling recruitment and survivorship of beech (Fagus crenata) were studied with special reference to the simultaneous death of undergrowing bamboo (Sasa kurilensis). The survival rate of beech seedlings on the floor whereSasa had withered was much higher than that on the floor whereSasa survived. Damping off caused the largest mortality among beech seedlings. However, the allocation pattern of matter to different
parts of the seedlings indicated that their survival was greatly affected by production economy. The dense cover of dwarf
bamboo prevented the establishment of beech seedling banks on the forest floor. The interval between the times when simultaneous
death ofSasa occur and the length of its recovery period are thus important factors controlling the dynamics of beech forests in Japan. 相似文献
84.
Treatment of Mid‐Pregnant Mice with KRN633, an Inhibitor of Vascular Endothelial Growth Factor Receptor Tyrosine Kinase,Induces Abnormal Retinal Vascular Patterning in Their Newborn Pups 下载免费PDF全文
Akane Morita Tsutomu Nakahara Naomichi Abe Asami Mori Kenji Sakamoto Tohru Nagamitsu Kunio Ishii 《Birth defects research. Part B, Developmental and reproductive toxicology》2014,101(4):293-299
We previously reported that treatment of mid‐pregnant mice with KRN633, a vascular endothelial growth factor receptor tyrosine kinase inhibitor, caused fetal growth restriction resulting from diminished vascularization in the placenta and fetal organs. In this study, we examined how the treatment of mid‐pregnant mice with KRN633 affects the development and morphology of vascular components (endothelial cells, pericytes, and basement membrane) in the retinas of their newborn pups. Pregnant mice were treated with KRN633 (5 mg/kg) once daily from embryonic day 13.5 until the day of delivery. Vascular components were examined using immunohistochemistry with specific markers for each component. Radial vascular growth in the retina was slightly delayed until postnatal day 4 (P4) in the newborn pups of KRN633‐treated mothers. On P8, compared with the pups of control mothers, the pups of KRN633‐treated mothers exhibited decreased numbers of central arteries and veins and abnormal branching of the central arteries. No apparent differences in pericytes or basement membrane were observed between the pups of control and KRN633‐treated mothers. These results suggest that a critical period for determining retinal vascular patterning is present at the earliest stages of retinal vascular development, and that the impaired vascular endothelial growth factor signaling during this period induces abnormal architecture in the retinal vascular network 相似文献
85.
Tatsuya Nagano Hironori Edamatsu Kazuyuki Kobayashi Nobuyuki Takenaka Masatsugu Yamamoto Naoto Sasaki Yoshihiro Nishimura Tohru Kataoka 《PloS one》2014,9(9)
Background
Phospholipase Cε (PLCε) is an effector of Ras and Rap small GTPases and expressed in non-immune cells. It is well established that PLCε plays an important role in skin inflammation, such as that elicited by phorbol ester painting or ultraviolet irradiation and contact dermatitis that is mediated by T helper (Th) 1 cells, through upregulating inflammatory cytokine production by keratinocytes and dermal fibroblasts. However, little is known about whether PLCε is involved in regulation of inflammation in the respiratory system, such as Th2-cells-mediated allergic asthma.Methods
We prepared a mouse model of allergic asthma using PLCε +/+ mice and PLCε ΔX/ΔX mutant mice in which PLCε was catalytically-inactive. Mice with different PLCε genotypes were immunized with ovalbumin (OVA) followed by the challenge with an OVA-containing aerosol to induce asthmatic response, which was assessed by analyzing airway hyper-responsiveness, bronchoalveolar lavage fluids, inflammatory cytokine levels, and OVA-specific immunoglobulin (Ig) levels. Effects of PLCε genotype on cytokine production were also examined with primary-cultured bronchial epithelial cells.Results
After OVA challenge, the OVA-immunized PLCε ΔX/ΔX mice exhibited substantially attenuated airway hyper-responsiveness and broncial inflammation, which were accompanied by reduced Th2 cytokine content in the bronchoalveolar lavage fluids. In contrast, the serum levels of OVA-specific IgGs and IgE were not affected by the PLCε genotype, suggesting that sensitization was PLCε-independent. In the challenged mice, PLCε deficiency reduced proinflammatory cytokine production in the bronchial epithelial cells. Primary-cultured bronchial epithelial cells prepared from PLCε ΔX/ΔX mice showed attenuated pro-inflammatory cytokine production when stimulated with tumor necrosis factor-α, suggesting that reduced cytokine production in PLCε ΔX/ΔX mice was due to cell-autonomous effect of PLCε deficiency.Conclusions
PLCε plays an important role in the pathogenesis of bronchial asthma through upregulating inflammatory cytokine production by the bronchial epithelial cells. 相似文献86.
Masaya Yamaoka Norikazu Maeda Yasunori Takayama Ryohei Sekimoto Yu Tsushima Keisuke Matsuda Takuya Mori Kana Inoue Hitoshi Nishizawa Makoto Tominaga Tohru Funahashi Iichiro Shimomura 《PloS one》2014,9(11)
Visceral fat adiposity plays an important role in the development of metabolic syndrome. We reported previously the impact of human visceral fat adiposity on gene expression profile of peripheral blood cells. Genes related to circadian rhythm were highly associated with visceral fat area and period homolog 1 (PER1) showed the most significant negative correlation with visceral fat area. However, regulation of adipose Per1 remains poorly understood. The present study was designed to understand the regulation of Per1 in adipose tissues. Adipose Per1 mRNA levels of ob/ob mice were markedly low at 25 and 35 weeks of age. The levels of other core clock genes of white adipose tissues were also low in ob/ob mice at 25 and 35 weeks of age. Per1 mRNA was mainly expressed in the mature adipocyte fraction (MAF) and it was significantly low in MAF of ob/ob mice. To examine the possible mechanisms, 3T3-L1 adipocytes were treated with H2O2, tumor necrosis factor-α (TNF-α), S100A8, and lipopolysaccharide (LPS). However, no significant changes in Per1 mRNA level were observed by these agents. Exposure of cultured 3T3-L1 adipocytes to low temperature (33°C) decreased Per1 and catalase, and increased monocyte chemoattractant protein-1 (Mcp-1) mRNA levels. Hypothermia also worsened insulin-mediated Akt phosphorylation in 3T3-L1 adipocytes. Finally, telemetric analysis showed low temperature of adipose tissues in ob/ob mice. In obesity, adipose hypothermia seems to accelerate adipocyte dysfunction. 相似文献
87.
Tohru Koide Takao Asano Hiroshi Matsushita Kintomo Takakura 《Journal of neurochemistry》1986,46(1):235-242
The effects of 15-hydroperoxyarachidonic acid (15-HPAA) on Na+, K+- and Mg+-ATPase activities in the blood-brain barrier (BBB) were examined using rat brain microvessels (MV). 15-HPAA markedly stimulated these ATPase activities in MV at low concentrations whereas the synaptosomal Na+, K+-ATPase activity was inhibited in a dose-dependent manner. Further neurochemical analysis revealed that this stimulatory effect of 15-HPAA in MV was not due to a simple detergent-like action of the compound on the membranes but rather to stimulation of the phospholipase A2 and lipoxygenase activity within MV. In addition, it was shown that free radical reactions were involved in the mechanism. Since such anti-edema drugs as 1,2-bis(nicotinamido)propane were proved to be potent suppressors of the enhanced ATPase activity, further speculations on the role of this effect for ischemic brain edema are offered. 相似文献
88.
Tohru Nakashizuka 《植被学杂志》1991,2(3):413-418
The growth and survival of coniferous and broad-leaved trees were followed over a 5-yr period in a temperate old-growth mixed forest in Japan, and dynamic features of the forest were studied in relation to the life history of the dominants, the coniferous Abies homolepis and the broad-leaved Fagus crenata. During this period, the gap formation rate was 31m2 ha?1yr?1, the mortality of trees > 2m high was 1.7%/yr, and the rate of loss in basal area 1.4%/yr. These values were much higher than the recruitment, 0.3%/yr, and the total growth of surviving and new trees, 0.6%/yr, owing to the inhibition of regeneration by understorey dwarf bamboo (Sasa borealis). A transition matrix model based on DBH size classes predicts that the basal area of the forest will decrease by 14% in 50 yr, but that the DBH distribution of trees > 10 cm diameter will change little. Equilibrium DBH distributions assuming recruitment being equal to mortality, were quite different between broad-leaved and coniferous trees, reflecting different survivorship curves of the two dominants. The composition and structure of the forest may change depending on the pattern and frequency of disturbances, or episodic events, notably the synchronous death of Sasa borealis. 相似文献
89.
90.
Kambe T Maruyama T Nakai Y Yoshida H Oida H Maruyama T Abe N Nishiura A Nakai H Toda M 《Bioorganic & medicinal chemistry》2012,20(7):2235-2251
To identify potent EP2/EP4 dual agonists with excellent subtype selectivity, a series of γ-lactam prostaglandin E analogs bearing a 16-phenyl ω-chain were synthesized and evaluated. Structural hybridization of 1 and 2, followed by more detailed chemical modification of the benzoic acid moiety, led us to the discovery of a 2-mercaptothiazole-4-carboxylic acid analog 3 as the optimal compound in the series. An isomer of this compound, the 2-mercaptothiazole-5-carboxylic acid analog 13, showed 34-fold and 13-fold less potent EP2 and EP4 receptor affinities, respectively. Structure activity relationship data from an in vitro mouse receptor binding assay are presented. Continued evaluation in an in vivo rat model of another 2-mercaptothiazole-4-carboxylic acid analog 17, optimized for sustained compound release from PLGA microspheres, demonstrated its effectiveness in a rat bone fracture-healing model following topical administration. 相似文献