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991.
Matsuno Y Deguchi J Hirasawa Y Ohyama K Toyoda H Hirobe C Ekasari W Widyawaruyanti A Zaini NC Morita H 《Bioorganic & medicinal chemistry letters》2008,18(13):3774-3777
Two new cassane-type diterpenes, sucutiniranes A (1) and B (2), have been isolated from the seeds of Bowdichia nitida together with 6alpha-acetoxyvouacapane (3) and 6alpha,7beta-diacetoxyvouacapane (4), and the structures of 1 and 2 were elucidated by using 2D NMR data and chemical correlations. Sucutinirane A (1) and 3 showed a moderate cytotoxicity against human colon carcinoma COLO201 cells, and 6alpha,7beta-diacetoxyvouacapane (4) showed in vitro antiplasmodial activity against parasite Plasmodium falciparum 3D7. 相似文献
992.
Hema Balakrishna Bhat Takuma Kishimoto Mitsuhiro Abe Asami Makino Takehiko Inaba Motohide Murate Naoshi Dohmae Atsushi Kurahashi Kozo Nishibori Fumihiro Fujimori Peter Greimel Reiko Ishitsuka Toshihide Kobayashi 《Journal of lipid research》2013,54(10):2933-2943
A mixture of sphingomyelin (SM) and cholesterol (Chol) exhibits a characteristic lipid raft domain of the cell membranes that provides a platform to which various signal molecules as well as virus and bacterial proteins are recruited. Several proteins capable of specifically binding either SM or Chol have been reported. However, proteins that selectively bind to SM/Chol mixtures are less well characterized. In our screening for proteins specifically binding to SM/Chol liposomes, we identified a novel ortholog of Pleurotus ostreatus, pleurotolysin (Ply)A, from the extract of edible mushroom Pleurotus eryngii, named PlyA2. Enhanced green fluorescent protein (EGFP)-conjugated PlyA2 bound to SM/Chol but not to phosphatidylcholine/Chol liposomes. Cell surface labeling of PlyA2-EGFP was abolished after sphingomyelinase as well as methyl-β-cyclodextrin treatment, removing SM and Chol, respectively, indicating that PlyA2-EGFP specifically binds cell surface SM/Chol rafts. Tryptophan to alanine point mutation of PlyA2 revealed the importance of C-terminal tryptophan residues for SM/Chol binding. Our results indicate that PlyA2-EGFP is a novel protein probe to label SM/Chol lipid domains both in cell and model membranes. 相似文献
993.
Edwin W. Taylor Nini Skovgaard Cleo A.C. Leite Marina Sartori Gabrielle S. de Paula Augusto S. Abe 《Journal of thermal biology》2012
Bullfrogs, Lithobathes catesbeianus, bearing a femoral artery cannula were held at 3 temperatures (10, 20 and 30 °C) for 24 h. Changes in heart rate were recorded before and after injection of cholinergic and adrenergic antagonists. Normal heart rate doubled for each temperature increment. Adrenergic tone on the heart varied around 20% at all 3 temperatures but cholinergic tone increased from −5% to 10% between 10 and 30 °C. In contrast, cholinergic tone increased from 75% at 5 °C to 329% at 25 °C in Xenopus laevis. Injection of the neural tracer True Blue into the cervical vagus of the bullfrog revealed a single location for vagal preganglionic neurons (VPN) in the dorsal vagal motor nucleus (DVN), while Xenopus had 30% of its VPN in a ventro-lateral group outside the DVN. Broader comparative studies have suggested that differences in the extent of vagal tone may relate to the location of VPN in the brainstem and this may be the case in these amphibians. 相似文献
994.
Abe T 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2002,21(6):291-295
A large inter-individual variation is seen in muscle fascicle length of the athletes but the reasons for this phenomenon are unclear. The purpose of this study was to determine whether genetic factors contribute to the variances in muscle architectural characteristics. Nine monozygous twin pairs (3 males and 6 females), mean age 23 years (range 17-40) were studied. Fascicle length, pennation angle, and muscle thickness of the medial (MG) and lateral (LG) gastrocnemius muscles were measured in vivo by B-mode ultrasound. In the LG muscle intrapair resemblance (P < 0.01) for fascicle length (r = 0.98), pennation angle (r = 0.94) and muscle thickness (r = 0.86) were observed. In MG muscle, however, there was no intrapair resemblance for fascicle length (r = 0.66, P > 0.05), although pennation angle (r = 0.73, P < 0.05) and muscle thickness (r = 0.86, P < 0.01) were significant. Mean percent intrapair difference in LG and MG muscles were 1.8% and 5.1% for fascicle length, 11.3% and 12.3% for pennation angle and 12.4% and 9.9% for muscle thickness, respectively. There is intrapair difference between muscle thickness and pennation angle in both MG (r = 0.69, P < 0.05) and LG (r = 0.70, P < 0.05) muscles. However, no significant correlation was observed for intrapair difference between muscle thickness and fascicle length in both muscles (MG, r = 0.46; LG, r = 0.40). It appears that genetic predisposition is the predominant factor for the determination of muscle fascicle length. However, a lack of intrapair resemblance in MG fascicle length raises the possibility that fascicle length may be further influenced by external environmental factors such as physical training. 相似文献
995.
Yuko Kimura Noboru Takamura Masato Fukunaga Mitsuo Kanagae Yasuyo Abe Kiyoshi Aoyagi 《Biomarkers》2013,18(3):291-297
Primary objective: To carry out a preliminary evaluation of subclinical inflammation and its genetic background in young adults.Research design: Fifty-five healthy Japanese young adults aged 19–27 years (37 males and 18 females, mean age: 22.3 years), and 58 healthy Japanese adults aged 40 to 60 years (21 males and 37 females, mean age: 51.5 years) were included in this study.Methods and procedures: We measured plasma high-sensitive C-reactive protein (hs-CRP) levels and screened for the C677T polymorphism of the 5-10 methylenetetrahydrofolate reductase gene (MTHFR), which is considered a genetic risk factor for atherosclerosis, by HinfI digestion.Main outcomes and results: Hs-CRP levels of the young adult group were significantly lower than the levels of the middle aged group (0.014±0.030 mg/dl vs. 0.031±0.040 mg/dl, p=0.005). The levels were significantly higher in males than in females (0.028±0.019 mg/dl vs. 0.013±0.010 mg/dl, p=0.008) among young adults. Furthermore, we evaluated the relationship of the C677T genotype and hs-CRP values, but found no association between them.Conclusions: Although the sample size is limited, our preliminary study demonstrated the profiles of hs-CRP in Japanese young adults. Further investigation will be needed to establish the guidelines for customized school health education using sensitive laboratory and genetic markers. 相似文献
996.
Kotaro Oyama Tomomi Arai Akira Isaka Taku Sekiguchi Hideki Itoh Yusuke Seto Makito Miyazaki Takeshi Itabashi Takashi Ohki Madoka Suzuki Shin'ichi Ishiwata 《Biophysical journal》2015,109(2):355-364
Living cells sense absolute temperature and temporal changes in temperature using biological thermosensors such as ion channels. Here, we reveal, to our knowledge, a novel mechanism of sensing spatial temperature gradients within single cells. Spherical mitotic cells form directional membrane extensions (polar blebs) under sharp temperature gradients (≥∼0.065°C μm−1; 1.3°C temperature difference within a cell), which are created by local heating with a focused 1455-nm laser beam under an optical microscope. On the other hand, multiple nondirectional blebs are formed under gradual temperature gradients or uniform heating. During heating, the distribution of actomyosin complexes becomes inhomogeneous due to a break in the symmetry of its contractile force, highlighting the role of the actomyosin complex as a sensor of local temperature gradients. 相似文献
997.
Recombinant chalcone synthase (CHS) from Scutellaria baicalensis and stilbene synthase (STS) from Arachis hypogaea accepted CoA esters of long-chain fatty acid (CHS up to the C12 ester, while STS up to the C14 ester) as a starter substrate, and carried out sequential condensations with malonyl-CoA, leading to formation of triketide and tetraketide alpha-pyrones. Interestingly, the C6, C8, and C10 esters were kinetically favored by the enzymes over the physiological starter substrate; the kcat/KM values were 1.2- to 1.9-fold higher than that of p-coumaroyl-CoA. The catalytic diversities of the enzymes provided further mechanistic insights into the type III PKS reactions, and suggested involvement of the CHS-superfamily enzymes in the biosynthesis of long-chain alkyl polyphenols such as urushiol and ginkgolic acid in plants. 相似文献
998.
Harada Y Tanabe E Watanabe R Weiss BD Matsumoto A Ariga H Koiwai O Fukui Y Kubo M June CH Abe R 《The Journal of biological chemistry》2001,276(12):9003-9008
999.
Kouki?HikosakaEmail author Yusuke?Onoda Toshihiko?Kinugasa Hisae?Nagashima Niels?PR?Anten Tadaki?Hirose 《Ecological Research》2005,20(3):243-253
Elevated CO2 enhances photosynthesis and growth of plants, but the enhancement is strongly influenced by the availability of nitrogen. In this article, we summarise our studies on plant responses to elevated CO2. The photosynthetic capacity of leaves depends not only on leaf nitrogen content but also on nitrogen partitioning within a leaf. In Polygonum cuspidatum, nitrogen partitioning among the photosynthetic components was not influenced by elevated CO2 but changed between seasons. Since the alteration in nitrogen partitioning resulted in different CO2-dependence of photosynthetic rates, enhancement of photosynthesis by elevated CO2 was greater in autumn than in summer. Leaf mass per unit area (LMA) increases in plants grown at elevated CO2. This increase was considered to have resulted from the accumulation of carbohydrates not used for plant growth. With a sensitive analysis of a growth model, however, we suggested that the increase in LMA is advantageous for growth at elevated CO2 by compensating for the reduction in leaf nitrogen concentration per unit mass. Enhancement of reproductive yield by elevated CO2 is often smaller than that expected from vegetative growth. In Xanthium canadense, elevated CO2 did not increase seed production, though the vegetative growth increased by 53%. As nitrogen concentration of seeds remained constant at different CO2 levels, we suggest that the availability of nitrogen limited seed production at elevated CO2 levels. We found that leaf area development of plant canopy was strongly constrained by the availability of nitrogen rather than by CO2. In a rice field cultivated at free-air CO2 enrichment, the leaf area index (LAI) increased with an increase in nitrogen availability but did not change with CO2 elevation. We determined optimal LAI to maximise canopy photosynthesis and demonstrated that enhancement of canopy photosynthesis by elevated CO2 was larger at high than at low nitrogen availability. We also studied competitive asymmetry among individuals in an even-aged, monospecific stand at elevated CO2. Light acquisition (acquired light per unit aboveground mass) and utilisation (photosynthesis per unit acquired light) were calculated for each individual in the stand. Elevated CO2 enhanced photosynthesis and growth of tall dominants, which reduced the light availability for shorter subordinates and consequently increased size inequality in the stand. 相似文献
1000.
Kobayashi T Liu X Wen FQ Fang Q Abe S Wang XQ Hashimoto M Shen L Kawasaki S Kim HJ Kohyama T Rennard SI 《Biochemical and biophysical research communications》2005,327(2):393-398
Transforming growth factor-beta1 (TGF-beta1) is a key factor in a variety of physiological and pathological processes. Vascular endothelial growth factor (VEGF) is a key angiogenic factor, and vascular change is one of the features of airway remodeling. We examined the effect of TGF-beta1 on VEGF production by fibroblasts from mice lacking expression of Smad2 or Smad3 as well as human lung fibroblasts treated with or without Smad2 or Smad3 siRNA. TGF-beta1 stimulated VEGF production by fibroblasts from Smad2 deficient animals and wildtype animals. In contrast, TGF-beta1 did not affect VEGF production by fibroblasts from Samd3 deficient mice. Similarly, TGF-beta1 failed to stimulate VEGF production by HFL-1 cells treated with Samd3 siRNA but significantly increased VEGF production by the cells treated with Smad2 siRNA. These result suggest that TGF-beta1 stimulation of VEGF production by fibroblasts is regulated by Smad3 but not by Smad2 signaling. 相似文献