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81.
Toshio Yoshida Shigeru Muraki Hiroshi Kawamura Akira Komatsu 《Bioscience, biotechnology, and biochemistry》2013,77(3):343-352
The main component of Japanese Ho-leaf oil has been shown to be (?)-linalool (80~90%), and the following twenty minor constituents newly have been identified; methyl vinyl ketone, methyl isobutyl ketone, mesityl oxide, β-pinene, myrcene, (+)-limonene, cis- and trans-ocimene, n-hexanol, cis-3-hexenol, cis- and trans-linalool oxide, (?)-1-terpinen-4-ol, (+)-cis and (+)-trans-2,6,6-trimethyl-2-vinyl-5-hydroxytetrahydropyran, citronellol, nerol, (+)-β-selinene, (+)-tagetonol and (?)-trans-hotrienol. (+)-Tagetonol and (?)-trans-hotrienol have been demonstrated to be (+)-3,7-dimethyl-3-hydroxy-1-octen-5-one (III) and (3R)-(?)-trans-3,7-dimethyl-3-hydroxy-1,5,7-octatriene (IX), respectively. 相似文献
82.
Masaaki Yoshikawa Etsuro Sugimoto Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(5):1005-1013
It was indicated from ultraviolet difference spectra and ultracentrifugal experiments that associations occurred between two casein components (αs- and κ-caseins, β- and κ-caseins and αs- and β-caseins) at lower CaCl2 concentrations (2~3 mm) and that aromatic amino acid residues participated in the associations. Chemical modification studies with 2-hydroxy-5-nitrobenzylbromide indicated that tryptophane residues of each casein component were not essential for these associations. It was also demonstrated by nitration of tyrosine residues with tetranitromethane that tyrosine residues of κ-casein were essential for αs·κ-association and for β·κ-association and that tyrosine residues of αs-casein were important to αs·β-association.Interactions between casein components were also studied at higher CaCl2 concentration (10 mm) which is enough for micelle formation. It was found that tyrosine residues of κ- casein played an important role for the stabilization of αs- and β-caseins. Properties of the nitrated-β-casein were almost the same as that of the native β-casein except the absorption spectrum. αs·β-Interaction in the presence of 10 mm CaCl2 was investigated by use of the nitrated-β-casein instead of the native β-casein. It was proved that αs-casein was stabilized by the nitrated-β-casein and that precipitation of the nitrated-β-casein increased in the presence of αs-casein.The mechanism of interactions between casein components at higher CaCl2 concentration (10 mm) are discussed in connection with the associations at lower CaCl2 concentrations (2~3 mm). 相似文献
83.
84.
Ryosuke Tateishi Shuichiro Shiina Masaaki Akahane Jiro Sato Yuji Kondo Ryota Masuzaki Hayato Nakagawa Yoshinari Asaoka Tadashi Goto Kuni Otomo Masao Omata Haruhiko Yoshida Kazuhiko Koike 《PloS one》2013,8(4)
Background
In the treatment of hepatocellular carcinoma (HCC), hepatic resection has the advantage over radiofrequency ablation (RFA) in terms of systematic removal of a hepatic segment.Methods
We enrolled 303 consecutive patients of a single naïve HCC that had been treated by RFA at The University of Tokyo Hospital from 1999 to 2004. Recurrence was categorized as either intra- or extra-subsegmental as according to the Couinaud''s segment of the original nodule. To assess the relationship between the subsegments of the original and recurrent nodules, we calculated the kappa coefficient. We assessed the risk factors for intra- and extra-subsegmental recurrence independently using univariate and multivariate Cox proportional hazard regression. We also assessed the impact of the mode of recurrence on the survival outcome.Results
During the follow-up period, 201 patients in our cohort showed tumor recurrence distributed in a total of 340 subsegments. Recurrence was categorized as exclusively intra-subsegmental, exclusively extra-subsegmental, and simultaneously intra- and extra-subsegmental in 40 (20%), 110 (55%), and 51 (25%) patients, respectively. The kappa coefficient was measured at 0.135 (95% CI, 0.079–0.190; P<0.001). Multivariate analysis revealed that of the tumor size, AFP value and platelet count were all risk factors for both intra- and extra-subsegmental recurrence. Of the patients in whom recurrent HCC was found to be exclusively intra-subsegmental, extra-subsegmental, and simultaneously intra- and extra-subsegmental, 37 (92.5%), 99 (90.8%) and 42 (82.3%), respectively, were treated using RFA. The survival outcomes after recurrence were similar between patients with an exclusively intra- or extra-subsegmental recurrence.Conclusions
The effectiveness of systematic subsegmentectomy may be limited in the patients with both HCC and chronic liver disease who frequently undergo multi-focal tumor recurrence. 相似文献85.
Tomohiro Iguchi Sho Nambara Takaaki Masuda Hisateru Komatsu Masami Ueda Shinya Kidogami Yushi Ogawa Qingjiang Hu Kuniaki Sato Tomoko Saito Hidenari Hirata Shotaro Sakimura Ryutaro Uchi Naoki Hayashi Shuhei Ito Hidetoshi Eguchi Keishi Sugimachi Yoshihiko Maehara Koshi Mimori 《PloS one》2016,11(11)
miR-146a plays important roles in cancer as it directly targets NUMB, an inhibitor of Notch signaling. miR-146a is reportedly regulated by a G>C polymorphism (SNP; rs2910164). This polymorphism affects various cancers, including colorectal cancer (CRC). However, the clinical significance of miR-146a polymorphism in CRC remains unclear. A total of 59 patients with CRC were divided into 2 groups: a CC/CG genotype (n = 32) and a GG genotype (n = 27), based on the miR-146a polymorphism. cDNA microarray analysis was performed using 59 clinical samples. Significantly enriched gene sets in each genotype were extracted using GSEA. We also investigated the association between miR-146a polymorphism and miR-146a, NUMB expression or migratory response in CRC cell lines. The CC/CG genotype was associated with significantly more synchronous liver metastasis (p = 0.007). A heat map of the two genotypes showed that the expression profiles were clearly stratified. GSEA indicated that Notch signaling and JAK/STAT3 signaling were significantly associated with the CC/CG genotype (p = 0.004 and p = 0.023, respectively). CRC cell lines with the pre-miR-146a/C revealed significantly higher miR-146a expression (p = 0.034) and higher NUMB expression and chemotactic activity. In CRC, miR-146a polymorphism is involved in liver metastasis. Identification of this polymorphism could be useful to identify patients with a high risk of liver metastasis in CRC. 相似文献
86.
87.
The plant‐specific CDKB1‐CYCB1 complex mediates homologous recombination repair in Arabidopsis 下载免费PDF全文
88.
Anandarajan Thiyagarajan Masaaki Toyama Masanori Baba Ashoke Sharon 《Nucleosides, nucleotides & nucleic acids》2016,35(6):305-314
The present study includes the exploration of new possible nucleoside mimetics based on 4-methoxy-7H-pyrrolo[2,3-d]pyrimidine carbocyclic nucleosides (4a–g), which were synthesized by 10–15 synthetic steps and characterized adequately. We report the anti-HCV activities and cytotoxicities of 4a–g. Compound 4a was analyzed by single crystal X-ray diffraction which showed some puckering in the cyclopentene ring with a 2′-endo conformation and anti-base disposition (χ = ?125.7°). 相似文献
89.
Seiya Sato Hiroaki Itamochi Nao Oumi Youhei Chiba Tetsuro Oishi Muneaki Shimada Shinya Sato Jun Chikumi Michiko Nonaka Akiko Kudoh Hiroaki Komatsu Tasuku Harada Toru Sugiyama 《Human cell》2016,29(4):181-187
A new cell line of human ovarian clear cell carcinoma (CCC), TU-OC-2, was established and characterized. The cells were polygonal in shape, grew in monolayers without contact inhibition and were arranged in islands like pieces of a jigsaw puzzle. The chromosome numbers ranged from 41 to 96. A low rate of proliferation was observed and the doubling time was 37.5 h. The IC50 values of cisplatin, 7-ethyl-10-hydroxycamptothecin (SN38), which is an active metabolite of camptothecin, and paclitaxel were 7.7 μM, 17.7 nM and 301 nM, respectively. The drug sensitivity assay indicated that TU-OC-2 was sensitive to SN38, but resistant to cisplatin and paclitaxel. Mutational analysis revealed that TU-OC-2 cells have no mutations of PIK3CA in exons 9 and 20 and of TP53 in exons 4–9. We observed the loss of ARID1A protein expression in TU-OC-2 cells by western blot analysis and in the original tumor tissue by immunohistochemistry. This cell line may be useful for studying the chemoresistant mechanisms of CCC and exploring novel therapeutic targets such as the ARID1A-related signaling pathway. 相似文献
90.
Takashi Ohnuki Masahiko Ejiri Masaaki Kizuka Mie Fujiwara Takahide Nishi 《Bioorganic & medicinal chemistry letters》2019,29(2):199-203
We herein report a practical one-step glucuronidation method by biotransformation using Streptomyces sp. SANK 60895. This novel direct method of biotransformation has been shown to be more practical and scalable for glucuronidation than previously reported chemical and enzymatic procedures given its simplicity, high β-selectivity, cost-effectiveness, and reproducibility. We applied the present method to the synthesis of acyl glucuronide and hydroxy-β-glucuronide of mycophenolic acid and compound 4, respectively. This method was also shown to be applicable to the N-glucuronidation of various compounds. 相似文献