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121.
This study investigated the seasonal change in xylem growth of Japanese red pine (Pinus densiflora). Wood cores were sampled at 2-week intervals from April to November in 2012 using the microcoring method. Daily increment rates of tracheid number and tree-ring width were compared with seasonal changes in daily mean temperature and photoperiod. Xylem growth started in early to late May and stopped in late October to early November. The maximum daily increment rates of tracheid number and tree-ring width were in early July. The 95 % confidence intervals of the timing of the maximum daily increment rates included the summer solstice (23 June) with the longest photoperiod, but not the warmest day (30 July). The maximum daily increment rate of xylem growth is thought to be controlled by the photoperiod rather than by temperature. The daily mean temperature exceeded 20 °C after the summer solstice, indicating that temperature is not a limiting factor for xylem growth. This study suggests that the timing of maximum daily increment rates of xylem growth of P. densiflora is controlled by the photoperiod. 相似文献
122.
Kou Kayamori Ken-ichi Katsube Kei Sakamoto Yoshio Ohyama Hideaki Hirai Akane Yukimori Yae Ohata Takumi Akashi Masao Saitoh Kiyoshi Harada Hiroyuki Harada Akira Yamaguchi 《PloS one》2016,11(4)
Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs. 相似文献
123.
The plant‐specific CDKB1‐CYCB1 complex mediates homologous recombination repair in Arabidopsis 下载免费PDF全文
124.
Makoto Nakabayashi Naoki Shibata Emi Ishido-Nakai Mayumi Kanagawa Yota Iio Hirofumi Komori Yasufumi Ueda Noriko Nakagawa Seiki Kuramitsu Yoshiki Higuchi 《Extremophiles : life under extreme conditions》2016,20(3):275-282
TTHA0829 from Thermus thermophilus HB8 has a molecular mass of 22,754 Da and is composed of 210 amino acid residues. The expression of TTHA0829 is remarkably elevated in the latter half of logarithmic growth phase. TTHA0829 can form either a tetrameric or dimeric structure, and main-chain folding provides an N-terminal cystathionine-β-synthase (CBS) domain and a C-terminal aspartate-kinase chorismate-mutase tyrA (ACT) domain. Both CBS and ACT are regulatory domains to which a small ligand molecule can bind. The CBS domain is found in proteins from organisms belonging to all kingdoms and is observed frequently as two or four tandem copies. This domain is considered as a small intracellular module with a regulatory function and is typically found adjacent to the active (or functional) site of several enzymes and integral membrane proteins. The ACT domain comprises four β-strands and two α-helices in a βαββαβ motif typical of intracellular small molecule binding domains that help control metabolism, solute transport and signal transduction. We discuss the possible role of TTHA0829 based on its structure and expression pattern. The results imply that TTHA0829 acts as a cell-stress sensor or a metabolite acceptor. 相似文献
125.
Guilherme Rocha Melo Gondim Fabiana Baroni Alves Makdissi Ricardo Cesar Fogaroli Juan Bautista Donoso Collins Hirofumi Iyeyasu Douglas Guedes de Castro Maria Letícia Gobo Silva Michael Jenwei Chen Tharcisio Machado Coelho Henderson Ramos Antônio Cássio Assis Pellizzon 《Reports of Practical Oncology and Radiotherapy》2019,24(6):551-555
BackgroundWhole breast irradiation reduces loco-regional recurrence and risk of death in patients submitted to breast-conserving treatment. Data show that radiation to the index quadrant alone may be enough in selected patients.AimTo report the experience with intra-operative radiotherapy (IORT) with Electron-beam Cone in Linear Accelerator (ELIOT) and the results in overall survival, local control and late toxicity of patients submitted to this treatment.Materials and Methods147 patients treated with a median follow up of 6.9 years (0.1?11.5 years). The actuarial local control and overall survival probabilities were estimated using the Kaplan Meier method. All tests were two-sided and p ? 0.05 was considered statistically significant.ResultsOverall survival of the cohort in 5 years, in the median follow up and in 10 years was of 98.3%, 95.1% and 95.1%, respectively, whereas local control in 5 years, in the median follow up and in 10 years was of 96%, 94.9% and 89.5%, respectively. Two risk groups were identified for local recurrence depending on the estrogen or progesterone receptors, axillary or margin status and lymphovascular invasion (LVI) (p = 0.016).ConclusionsIORT is a safe and effective treatment. Rigorous selection is important to achieve excellent local control results. 相似文献
126.
Elissa Chairani Takao Fuchigami Hirofumi Koyama Yusuke Ono Mikio Iijima Michiko Kishida Toshiro Kibe Norifumi Nakamura Shosei Kishida 《Biochemistry and Biophysics Reports》2022
Ameloblastoma is an odontogenic tumor located in the bone jaw with clinical characteristics of extensive bone resorption. It is a locally invasive tumor with a high recurrence rate despite adequate surgical removal. In bone disease, tumors and other cells including osteoblasts, osteoclasts, and osteocytes in the bone microenvironment contribute to the pathogenesis of tumor growth. However, the effect of osteoblasts on ameloblastoma cells is not well-understood, and there has been limited research on interactions between them.This study investigated interactions between ameloblastoma cells and osteoblasts using a human ameloblastoma cell line (AM-3 ameloblastoma cells) and a murine pre-osteoblast cell line (MC3T3-E1 cells). We treated each cell type with the conditioned medium by the other cell type. We analyzed the effect on cytokine production by MC3T3-E1 cells and the production of MMPs by AM-3 cells. Treatment with AM-3-conditioned medium induced inflammatory cytokine production of IL-6, MCP-1, and RANTES from MC3T3-E1 cells. The use of an IL-1 receptor antagonist suppressed the production of these inflammatory cytokines by MC3T3-E1 cells stimulated with AM-3-conditioned medium. The MC3T3-E1-conditioned medium triggered the expression of MMP-2 from AM-3 cells. Furthermore, we have shown that the proliferation and migration activity of AM-3 cells were accelerated by MC3T3-E1 conditioned media.In conclusion, these intercellular signalings between ameloblastoma cells and osteoblasts may play multiple roles in the pathogenesis of ameloblastoma. 相似文献
127.
128.
Here we show that the cell-surface expression of the alpha subunit of H(+)-ATP synthase is markedly increased during adipocyte differentiation. Treatment of differentiated adipocytes with small molecule inhibitors of H(+)-ATP synthase or antibodies against alpha and beta subunits of H(+)-ATP synthase leads to a decrease in cytosolic lipid droplet accumulation. Apolipoprotein A-I, which has been shown to bind to the ectopic beta-chain of H(+)-ATP synthase and inhibit the activity of cell-surface H(+)-ATP synthase, also was found to inhibit cytosolic lipid accumulation. These results suggest that the cell-surface H(+)-ATP synthase has a previously unsuspected role in lipid metabolism in adipocytes. 相似文献
129.
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
130.
Ashibe B Hirai T Higashi K Sekimizu K Motojima K 《The Journal of biological chemistry》2007,282(28):20763-20773
Fatty aldehyde dehydrogenase (FALDH, ALDH3A2) is thought to be involved in the degradation of phytanic acid, a saturated branched chain fatty acid derived from chlorophyll. However, the identity, subcellular distribution, and physiological roles of FALDH are unclear because several variants produced by alternative splicing are present in varying amounts at different subcellular locations. Subcellular fractionation experiments do not provide a clear-cut conclusion because of the incomplete separation of organelles. We established human cell lines heterologously expressing mouse FALDH from each cDNA without tagging under the control of an inducible promoter and detected the variant FALDH proteins using a mouse FALDH-specific antibody. One variant, FALDH-V, was exclusively detected in peroxisomal membranes. Human FALDH-V with an amino-terminal Myc sequence also localized to peroxisomes. The most dominant form, FALDH-N, and other variants examined, however, were distributed in the endoplasmic reticulum. A gas chromatography-mass spectrometry-based analysis of metabolites in FALDH-expressing cells incubated with phytol or phytanic acid showed that FALDH-V, not FALDH-N, is the key aldehyde dehydrogenase in the degradation pathway and that it protects peroxisomes from oxidative stress. In contrast, both FALDHs had a protective effect against oxidative stress induced by a model aldehyde for lipid peroxidation, dodecanal. These results suggest that FALDH variants are produced by alternative splicing and share an important role in protecting against oxidative stress in an organelle-specific manner. 相似文献