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231.
Aki Fujiwara-Igarashi Yuko Goto-KoshinoHiroyuki Mochizuki Masahiko SatoYasuhito Fujino Koichi OhnoHajime Tsujimoto 《Research in veterinary science》2014
To investigate the epigenetic regulation of the p16 gene in canine lymphoid tumor cells, its methylation status was examined in four canine lymphoid tumor cell lines. In three canine lymphoid tumor cell lines (CLBL-1, GL-1, and UL-1) with low-level p16 mRNA expression, 20 CpG sites in the promoter region of p16 gene were consistently methylated although all of the CpG sites were not methylated in another cell line (CL-1) and normal lymph node cells. The expression level of p16 mRNA in these three cell lines was restored after cultivation in the presence of a methylation inhibitor, 5-Aza-2′-deoxycitidine, indicating inactivation of p16 gene via hypermethylation. This study revealed the inactivation of p16 gene through hypermethylation of its CpG island in a fraction of canine lymphoid tumor cells. 相似文献
232.
A liquid chromatography-atmospheric pressure photoionization (APPI)-mass spectrometry method was developed for the determination of 22 carbamates including their metabolites in vegetables and fruits. For the optimization of APPI, several APPI ion source parameters were examined. As a result, many carbamates with APPI using the optimized parameter gave simple mass spectra, and a strong signal corresponding to [M + H](+) was observed except for aldicarb. However, some carbamate metabolites gave ammonium adduct ions [M + NH(4)](+) as base peak ions. The mean recovery of each carbamate from grape and onion samples spiked at 5 ng/g was 81.7-105.7%, with relative standard deviations of 3.3-5.9%. Furthermore, matrix constituents did not significantly influence the ionization efficiency. The limit of detection (S/N = 3) in grape and onion was in the range of 0.33-3.33 ng/g. For the robustness of this method, this system has been used to analyze 50 samples, and the intensities for all carbamates were found to be unaffected by the contamination of the APPI source by sample matrix constituents. This result indicates that the method is reliable. 相似文献
233.
Eiichi TAKASU Humiei YAMADA Nagao SHIMADA Yoshiaki YOSHIDA Masahiko SAIGUSA 《Soil Science and Plant Nutrition》2006,52(2):251-251
(pp. 1–7)
Application of phosphogypsum PG and limestone to Andisol were compared in terms of their effects on the growth and uptake of Ca in Komatsuna Brassica rapa L. cv. Natsurakuten. The studies were carried out in soil pot cultures, and both PG and limestone were applied to the Andisol at the rates of 0, 0.30, 0.75, 1.50 g kg−1 in the form of CaO.
Application of phosphogypsum PG and limestone to Andisol were compared in terms of their effects on the growth and uptake of Ca in Komatsuna Brassica rapa L. cv. Natsurakuten. The studies were carried out in soil pot cultures, and both PG and limestone were applied to the Andisol at the rates of 0, 0.30, 0.75, 1.50 g kg
- 1)
Limestone application resulted in an increase in the soil pH. On the other hand, no change was observed in the case of PG application at pH 6.1 ± 0.1 regardless of the application rate. Both soil EC and water-soluble Ca increased in proportion to the PG application rate, and this increase was approximately 5 times greater than that observed when limestone was applied at 1.50 g kg
−1 . The w-Ca/ex-Ca ratio (water-soluble Ca: 1 M acetic acid-extractable Ca) was clearly increased from 0.12 up to 0.26 in PG, while the value was slightly decreased from 0.12 to 0.05 in limestone.
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Plant growth inhibitory activity and active substances with allelopathic potential of cogongrass (Imperata cylindrica) rhizome 下载免费PDF全文
Masahiko Suzuki Tohru Tominaga Osamu Ohno Arihiro Iwasaki Kiyotake Suenaga Hisashi Kato‐Noguchi 《Weed Biology and Management》2018,18(2):92-98
Cogongrass (Imperata cylindrica [L.] Raeusch.) is a perennial rhizomatous grass that belongs to the Poaceae and is widely distributed in tropical, subtropical and temperate regions over the world. The grass is strongly invasive and is suggested to have allelopathic potential. However, limited information is available on allelopathic substances in cogongrass rhizomes. Therefore, the allelopathic potential and substances in cogongrass rhizomes were investigated. The extracts of cogongrass rhizomes inhibited the root and shoot growth of barnyard grass, ryegrass, timothy, cress, lettuce and alfalfa. After bioassay‐guided separations of the extracts, four growth inhibitory substances, 5‐methoxyflavone, 5,2′‐dimethoxyflavone, methyl caffeate and abscisic acid, were isolated. 5‐Methoxyflavone, 5,2′‐dimethoxyflavone and methyl caffeate significantly inhibited the root and shoot growth of cress at concentrations of ≥0.03–0.3 m mol L?1 and their concentrations required for 50% growth inhibition were 0.079–0.24, 0.23–1.1 and 0.59–0.88 m mol L?1, respectively. The other isolated substance, abscisic acid, has been reported to have strong growth inhibitory activity. Its concentrations required for 50% growth inhibition on cress were 0.31–0.61 μ mol L?1. The present study suggests that cogongrass rhizomes might have allelopathic potential and that those four substances might contribute to that potential. 相似文献