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Dispersion capabilities of new queens were studied in the two haplometrotic paper wasps Polistes riparius and P. snelleni. New queens were marked on the nests in the late summer and located in the next spring. Dispersion distances greatly varied among queens: although a large part of recovered queens nested in close proximity to their natal sites, some did disperse over 100–300 m. This suggests that queens' emigration from and immigration into the censused areas occurred to a substantial extent. On the whole, these species exhibited a weaker “philopatric” tendency than those so far studied for dispersion distance, and seem to have the potential for a long-distance dispersion. 相似文献
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Matsuo Tsukasa 《Journal of plant research》1983,96(2):127-133
The late-glacial logistic decline of spruce (Picea) populations (the intrinsic growth rate,r in yr?1=?0.0015) was progressively delayed toward cooler sites in Japan; spruce populations expanded asymptotically (r=0.0040?0.0045) in Sakhalin early in the Holocene. Such a time-transgressive range shift in spruce distribution, covering a wide latitudinal range (ca. 35–50°N), implies that the regional temperature rise was not instantaneous, but was rapid, being 0.0015–0.0025 C yr?1 from 13,000 to 10,000 years B.P. Spruce populations increased in response to Neoglacial cooling only at the margin of its distribution (r=0.0036), but then declined logistically 1,000 years B.P. (r=?0.0022). 相似文献
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2-Amino-2-deoxy-D-erythrose was isolated from the cell wall of the fruit body of Agaricus bisporus. The structure of the amino sugar was determined by mass spectrography and 1H-NMR spectrography of its acetylated derivative and by paper chromatographic comparisons with authentic 2-amino-2-deoxy-D-erythrose. This amino sugar is a component of the glycoprotein fraction from the cell wall. Its content in the glycoprotein increased markedly, especially during the ripening stage of the fruit body. 相似文献
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Miyuki Kusajima Moeka Fujita Hiromoto Yamakawa Tsukasa Ushiwatari Takamasa Mori Kazuki Tsukamoto 《Bioscience, biotechnology, and biochemistry》2020,84(7):1427-1435
ABSTRACT A newly identified chemical, 4-{3-[(3,5-dichloro-2-hydroxybenzylidene)amino]propyl}-4,5-dihydro-1H-pyrazol-5-one (BAPP) was characterized as a plant immunity activator. BAPP enhanced disease resistance in rice against rice blast disease and expression of a defense-related gene without growth inhibition. Moreover, BAPP was able to enhance disease resistance in dicotyledonous tomato and Arabidopsis plants against bacterial pathogen without growth inhibition, suggesting that BAPP could be a candidate as an effective plant activator. Analysis using Arabidopsis sid2-1 and npr1-2 mutants suggested that BAPP induced systemic acquired resistance (SAR) by stimulating between salicylic acid biosynthesis and NPR1, the SA receptor protein, in the SAR signaling pathway. 相似文献
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Akira Araumi Tsukasa Osaki Kazunobu Ichikawa Kosuke Kudo Natsuko Suzuki Sayumi Watanabe Masafumi Watanabe Tsuneo Konta 《Biochemistry and Biophysics Reports》2021
The choice of treatment for primary nephrotic syndrome depends on the pathologic type of the disorder. Renal biopsy is necessary for a definitive diagnosis, but it is burdensome for the patients, and can be avoided if tests could be performed using urine or plasma. In this study, we analyzed 100 urinary proteins, 141 plasma proteins, and 57 urine/plasma ratios in cases of diabetic nephropathy (DN; n = 11), minimal change nephrotic syndrome (MCNS; n = 14), and membranous nephropathy (MN; n = 23). We found that the combination of urinary retinol-binding protein 4 and SH3 domain-binding glutamic acid-rich-like protein 3 could distinguish between MCNS and DN, with an area under the curve (AUC) of 0.9740. On the other hand, a selectivity index (SI) based on serotransferrin and immunoglobulin G, which is often used in clinical practice, distinguished them with an AUC of 0.9091. Similarly, the combination of urinary afamin and complement C3 urine/plasma ratio could distinguish between MN and DN with an AUC of 0.9842, while SI distinguished them with an AUC of 0.8538. Evidently, the candidates identified in this study were superior to the SI method. Thus, the aim was to test these biomarkers for accurate diagnosis and to greatly reduce the burden on patients. 相似文献
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Yoshinori Takahashi Megan M. Young Jacob M. Serfass Tsukasa Hori Hong-Gang Wang 《Autophagy》2013,9(7):1107-1109
Evasion of apoptosis, which enables cells to survive and proliferate under metabolic stress, is one of the hallmarks of cancer. We have recently reported that SH3GLB1/Bif-1 functions as a haploinsufficient tumor suppressor to prevent the acquisition of apoptosis resistance and malignant transformation during Myc-driven lymphomagenesis. SH3GLB1 is a membrane curvature-inducing protein that interacts with BECN1 though UVRAG and regulates the post-Golgi trafficking of membrane-integrated ATG9A for autophagy. At the premalignant stage, allelic loss of Sh3glb1 enhances Myc-induced chromosomal instability and results in the upregulation of anti-apoptotic proteins, including MCL1 and BCL2L1. Notably, we found that Sh3glb1 haploinsufficiency increases mitochondrial mass in overproliferated prelymphomatous Eμ-Myc cells. Moreover, loss of Sh3glb1 suppresses autophagy-dependent mitochondrial clearance (mitophagy) in PARK2/Parkin-expressing mouse embryonic fibroblasts (MEFs) treated with the mitochondrial uncoupler CCCP. Interestingly, PARK2-expressing Sh3glb1-deficient cells accumulate ER-associated immature autophagosome-like structures after treatment with CCCP. Taken together, we propose a model of mitophagy in which SH3GLB1 together with the class III phosphatidylinositol 3-kinase complex II (PIK3C3CII) (PIK3R4-PIK3C3-BECN1-UVRAG) regulates the trafficking of ATG9A-containing Golgi-derived membranes (A9+GDMs) to damaged mitochondria for autophagosome formation to counteract oncogene-driven tumorigenesis. 相似文献
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Kosuke Murakami Chie Kurihara Tomoichiro Oka Takashi Shimoike Yoshiki Fujii Reiko Takai-Todaka YoungBin Park Takaji Wakita Tsukasa Matsuda Ryota Hokari Soichiro Miura Kazuhiko Katayama 《PloS one》2013,8(6)
Human noroviruses (NoVs) are a major cause of non-bacterial gastroenteritis. Although histo-blood group antigens (HBGAs) have been implicated in the initial binding of NoV, the mechanism of that binding before internalization is not clear. To determine the involvement of NoVs and HBGAs in cell binding, we examined the localization of NoV virus-like particles (VLPs) and HBGAs in a human intestinal cell line and the human ileum biopsy specimens by immunofluorescence microscopy. The localizations of Ueno 7k VLPs (genogroup II.6) and each HBGA (type H1-, H2- and Leb-HBGAs) on the human intestinal cell line, Caco-2, were examined by confocal laser-scanning microscopy. To explore any interactions of NoVs and HBGAs in vivo, fresh biopsy specimens from human ileum were directly incubated with NoV VLPs and examined by immunofluorescence microscopy. We found that VLP binding depended on the state of cell differentiation, but not on the presence of HBGAs. In differentiated Caco-2 cells, we detected no type H1 HBGAs, but VLPs bound to the cells anyway. We incubated fresh biopsies of human ileum directly with VLPs, a model that better replicates the in vivo environment. VLPs mainly bound epithelial cells and goblet cells. Although the incubations were performed at 4°C to hinder internalization, VLPs were still detected inside cells. Our results suggest that VLPs utilize molecule(s) other than HBGAs during binding and internalization into cells. 相似文献