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51.
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Masako Dannoura Yasuhiro Hirano Tetsuro Igarashi Masahiro Ishii Kenji Aono Keitaro Yamase 《Plant biosystems》2013,147(2):375-380
Abstract Coarse tree roots, which are responsible for most root carbon storage, are usually measured by destructive methods such as excavation and coring. Ground penetrating radar (GPR) is a non-destructive tool that could be used to detect coarse roots in forest soils. In this study, we examined whether the roots of Cryptomeria japonica, a major plantation species in Japan, can be detected with GPR. We also looked for factors that impact the analysis and detection of roots. Roots and wooden dowels of C. japonica were buried 30 cm deep in sandy granite soil. From GPR measurements with a 900 MHz antenna, the distribution and diameter of samples in several transects were recorded. The buried roots were detected clearly and could be distinguished at diameters of 1.1–5.2 cm. There were significant positive relationships between root diameter and parameters extracted from the resultant GPR waveform. The difference in water content between roots and soil is a crucial factor impacting the ability to detect roots with GPR. We conclude that GPR can be used as a non-destructive tool, but further investigation is needed to determine optimal conditions (e.g. water content) and analytical methods for using GPR to examine roots in forest sites. 相似文献
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Teppei Yamada Koichi Azuma Emi Muta Jintaek Kim Shunichi Sugawara Guang Lan Zhang Satoko Matsueda Yuri Kasama-Kawaguchi Yuichi Yamashita Takuto Yamashita Kazuto Nishio Kyogo Itoh Tomoaki Hoshino Tetsuro Sasada 《PloS one》2013,8(11)
Treatment with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib and erlotinib, has achieved high clinical response rates in patients with non–small cell lung cancers (NSCLCs). However, over time, most tumors develop acquired resistance to EGFR-TKIs, which is associated with the secondary EGFR T790M resistance mutation in about half the cases. Currently there are no effective treatment options for patients with this resistance mutation. Here we identified two novel HLA-A*0201 (A2)-restricted T cell epitopes containing the mutated methionine residue of the EGFR T790M mutation, T790M-5 (MQLMPFGCLL) and T790M-7 (LIMQLMPFGCL), as potential targets for EGFR-TKI-resistant patients. When peripheral blood cells were repeatedly stimulated in vitro with these two peptides and assessed by antigen-specific IFN-γ secretion, T cell lines responsive to T790M-5 and T790M-7 were established in 5 of 6 (83%) and 3 of 6 (50%) healthy donors, respectively. Additionally, the T790M-5- and T790M-7-specific T cell lines displayed an MHC class I-restricted reactivity against NSCLC cell lines expressing both HLA-A2 and the T790M mutation. Interestingly, the NSCLC patients with antigen-specific T cell responses to these epitopes showed a significantly less frequency of EGFR-T790M mutation than those without them [1 of 7 (14%) vs 9 of 15 (60%); chi-squared test, p = 0.0449], indicating the negative correlation between the immune responses to the EGFR-T790M-derived epitopes and the presence of EGFR-T790M mutation in NSCLC patients. This finding could possibly be explained by the hypothesis that immune responses to the mutated neo-antigens derived from T790M might prevent the emergence of tumor cell variants with the T790M resistance mutation in NSCLC patients during EGFR-TKI treatment. Together, our results suggest that the identified T cell epitopes might provide a novel immunotherapeutic approach for prevention and/or treatment of EGFR-TKI resistance with the secondary EGFR T790M resistance mutation in NSCLC patients. 相似文献
54.
Kota Yamamoto Xin Li Chang Shu Tetsuro Miyata Alan Dardik 《Journal of visualized experiments : JoVE》2013,(77)
Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound. 相似文献
55.
Masayoshi Oyama Ken-ichi Nakashima Tetsuro Kamiya Manami Haba Tetsuro Ito Hiroko Murata Toshiyuki Tanaka Tetsuo Adachi Munekazu Iinuma Takeshi Kinoshita 《Phytochemistry letters》2013,6(2):215-218
Two novel flavonoids, named meliflavones A (1) and B (2), were isolated from the leaves of Melicope triphylla (Lam.) Merr., along with thirteen known compounds (3–15). Four of the polymethoxyflavonoids bearing a prenyloxy (3-methylbut-2-enyloxy) function (1, 3–5) induced the expression of extracellular-superoxide dismutase (EC-SOD) in a human leukemic U937 cell-based assay. 相似文献
56.
Tetsuro Ito Kouko Nishiya Masayoshi Oyama Toshiyuki Tanaka Jin Murata Dedy Darnaedi Munekazu Iinuma 《Phytochemistry letters》2013,6(4):667-670
Two O-glucosides of resveratrol dimers, ampelopsin F-11b-O-β-glucopyranosides with enantiomeric aglycones [cordifoloside A (1) and cordifoloside B (2)] and an enantiomer of the aglycone [(?)-ampelopsin F] were isolated from the leaves of Shorea cordifolia (Dipterocarpaceae). These structures were identified on the basis of spectroscopic evidence and their absolute configurations were elucidated using circular dichroism data. This is the first report on oligostilbenoids that demonstrates the co-occurrence of diastereomeric O-glucosides with enantiomeric aglycones in this family. 相似文献
57.
Masaaki Konishi Seigo Sugiyama Koichi Sugamura Toshimitsu Nozaki Keisuke Ohba Junichi Matsubara Kenji Sakamoto Yasuhiro Nagayoshi Hitoshi Sumida Eiichi Akiyama Yasushi Matsuzawa Kentaro Sakamaki Satoshi Morita Kazuo Kimura Satoshi Umemura Hisao Ogawa 《PloS one》2013,8(4)
Background
Cardiac troponin is a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes. Troponin release from the coronary circulation remains to be determined because of the lower sensitivity of the conventional assay. We sought to determine basal and angina-induced troponin release using a highly sensitive troponin assay.Methods and Results
The cardiac troponin T levels in serum sampled from the peripheral vein (PV), the aortic root (AO), and the coronary sinus (CS) were measured in 105 consecutive stable patients with coronary risk factor(s) and suspected coronary artery disease (CAD) and in 33 patients without CAD who underwent an acetylcholine provocation test. At baseline, there was a significant increase in the troponin levels from AO [9.0 (6.4, 13.1) pg/mL for median (25th, 75th percentiles)] to CS [10.3 (7.3, 15.5) pg/mL, p<0.001] in 96 (91.4%) patients and the difference was 1.1 (0.4, 2.1) pg/mL, which reflected basal transcardiac troponin release (TTR). TTR was positively correlated with PV levels (r = 0.22, p = 0.03). Male sex, left ventricular hypertrophy determined by echocardiography, T-wave inversion, and CAD correlated with elevated TTR defined as above: median, 1.1 pg/mL. A significant increase in TTR was noted in 17 patients with coronary spasms [0.6 (0.2, 1.2) pg/mL, p<0.01] but not in 16 patients without spasms [0.0 (−0.5, 0.9) pg/mL, p = 0.73] after the acetylcholine provocation.Conclusion
Basal TTR in the coronary circulation was observed in most of the patients with suspected CAD and risk factor(s). This sensitive assay detected myocardial ischemia-induced increases in TTR caused by coronary spasms. 相似文献58.
Homma Yuri Mita Kazuei Nakamura Yuki Namiki Toshiki Noda Hiroaki Shinoda Tetsuro Togawa Toru 《Applied Entomology and Zoology》2020,55(1):45-54
Applied Entomology and Zoology - Juvenile hormone (JH) has crucial roles in insect physiology, including development, reproduction, and polyphenism. JH is synthesized in the corpora allata (CA)... 相似文献
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