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141.
142.
Tomoyuki Hayashi Hisashi Doyama Yukihiro Shirota Hirokazu Tsuji Youhei Marukawa Hajime Ohta Kazuhiro Miwa Takaharu Masunaga Shuichi Terasaki Yutaka Matano Kunihiro Tsuji Yoshibumi Kaneko Toshihide Okada Hiroshi Kurumaya Shuichi Kaneko 《PloS one》2014,9(7)
Objectives
Magnifying narrow-band imaging (M-NBI) is more accurate than white-light imaging for diagnosing small gastric cancers. However, it is uncertain whether moving M-NBI images have additional effects in the diagnosis of gastric cancers compared with still images.Design
A prospective multicenter cohort study.Methods
To identify the additional benefits of moving M-NBI images by comparing the diagnostic accuracy of still images only with that of both still and moving images. Still and moving M-NBI images of 40 gastric lesions were obtained by an expert endoscopist prior to this prospective multicenter cohort study. Thirty-four endoscopists from ten different Japanese institutions participated in the prospective multicenter cohort study. Each study participant was first tested using only still M-NBI images (still image test), then tested 1 month later using both still and moving M-NBI images (moving image test). The main outcome was a difference in the diagnostic accuracy of cancerous versus noncancerous lesions between the still image test and the moving image test.Results
Thirty-four endoscopists were analysed. There were no significant difference of cancerous versus noncancerous lesions between still and moving image tests in the diagnostic accuracy (59.9% versus 61.5%), sensitivity (53.4% versus 55.9%), and specificity (67.0% versus 67.6%). And there were no significant difference in the diagnostic accuracy between still and moving image tests of demarcation line (65.4% versus 65.5%), microvascular pattern (56.7% versus 56.9%), and microsurface pattern (48.1% versus 50.9%). Diagnostic accuracy showed no significant difference between the still and moving image tests in the subgroups of endoscopic findings of the lesions.Conclusions
The addition of moving M-NBI images to still M-NBI images does not improve the diagnostic accuracy for gastric lesions. It is reasonable to concentrate on taking sharp still M-NBI images during endoscopic observation and use them for diagnosis.Trial registration
Umin.ac.jp UMIN-CTR000008048 相似文献143.
Akihiro Nita Akinobu Matsumoto Ronghao Tang Chisa Shiraishi Kazuya Ichihara Daisuke Saito Mikita Suyama Tomoharu Yasuda Gaku Tsuji Masutaka Furue Bumpei Katayama Toshiyuki Ozawa Teruasa Murata Teruki Dainichi Kenji Kabashima Atsushi Hatano Masaki Matsumoto Keiichi I. Nakayama 《PLoS genetics》2021,17(8)
144.
145.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
146.
Hajime Yoshida Yoshitake Tanaka Kiyoshi Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(9):2121-2126
Six strains of bacteria belonging to Vibrio and Pseudomonas were selected as good producers of L-DOPA from L-tyrosine out of various bacteria. The condition for the formation of L-DOPA by Vibrio tyrosinaticus ATCC 19378 was examined and the following results were obtained. (1) Intermittent addition of L-tyrosine in small portions gave higher titer of L-DOPA than single addition of L-tyrosine. (2) Higher amount of L-DOPA was produced in stationary phase of growth than in logarithmic phase. (3) Addition of antioxidant, chelating agent or reductant such as L-ascorbic acid, araboascorbic acid, hydrazine, citric acid and 5-ketofructose increased the amount of L-DOPA formed. (4) L-Tyrosine derivatives such as N-acetyl-L-tyrosine amide, N-acetyl-L-tyrosine, L-tyrosine amide, L-tyrosine methyl ester and L-tyrosine benzyl ester were converted to the corresponding L-DOPA derivatives.In the selected condition about 4 mg/ml of L-DOPA was produced from 4.3 mg/ml of L-tyrosine. 相似文献
147.
Stefan C. Genet Yoshihiro Fujii Junko Maeda Masami Kaneko Matthew D. Genet Kiyoshi Miyagawa Takamitsu A. Kato 《Journal of cellular physiology》2013,228(7):1473-1481
Hyperthermia has long been known as a radio‐sensitizing agent that displays anti‐tumor effects, and has been developed as a therapeutic application. The mechanisms of hyperthermia‐induced radio‐sensitization are highly associated with inhibition of DNA repair. Our investigations aimed to show how hyperthermia inactivate homologous recombination repair in the process of sensitizing cells to ionizing radiation by using a series of DNA repair deficient Chinese Hamster cells. Significant differences in cellular toxicity attributable to hyperthermia at and above 42.5°C were observed. In wild‐type and non‐homologous end joining repair mutants, cells in late S phase showed double the amount heat‐induced radio‐sensitization effects of G1‐phase cells. Both radiation‐induced DNA double strand breaks and chromatin damage resulting from hyperthermia exposure was measured to be approximately two times higher in G2‐phase cells than G0/G1 cells. Additionally, G2‐phase cells took approximately two times as long to repair DNA damage over time than G0/G1‐phase cells. To supplement these findings, radiation‐induced Rad51 foci formations at DNA double strand break sites were observed to gradually dissociate in response to the temperature and time of hyperthermia exposure. Dissociated Rad51 proteins subsequently re‐formed foci at damage sites with time, and occurred in a trend also related to temperature and time of hyperthermia exposure. These findings suggest Rad51's dissociation and subsequent reformation at DNA double strand break sites in response to varying hyperthermia conditions plays an important role in hyperthermia‐induced radio‐sensitization. J. Cell. Physiol. 228: 1473–1481, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
148.
Shinsuke Mikami Ayumu Nakashima Keigo Nakagawa Tatsuya Maruhashi Yumiko Iwamoto Masato Kajikawa Takeshi Matsumoto Yasuki Kihara Kazuaki Chayama Kensuke Noma Mitsuo Ochi Masahiro Nishimura Koichiro Tsuji Yukio Kato Chikara Goto Yukihito Higashi 《PloS one》2013,8(7)
Background
The purpose of this study was to determine whether autologous mesenchymal stem cells (MSCs) implantation improves endothelial dysfunction in a rabbit ischemic limb model.Methods
We evaluated the effect of MSC implantation on limb blood flow (LBF) responses to acetylcholine (ACh), an endothelium-dependent vasodilator, and sodium nitroprusside (SNP), an endothelium-independent vasodilator, in rabbits with limb ischemia in which cultured MSCs were implanted (n = 20) or saline was injected as a control group (n = 20). LBF was measured using an electromagnetic flowmeter. A total of 106 MSCs were implanted into each ischemic limb.Results
Histological sections of ischemic muscle showed that capillary index (capillary/muscle fiber) was greater in the MSC implantation group than in the control group. Laser Doppler blood perfusion index was significantly increased in the MSC implantation group compared with that in the control group. LBF response to ACh was greater in the MSC group than in the control group. After administration of NG-nitro-L-arginine, a nitric oxide synthase inhibitor, LBF response to ACh was similar in the MSC implantation group and control group. Vasodilatory effects of SNP in the two groups were similar.Conclusions
These findings suggest that MSC implantation induces angiogenesis and augments endothelium-dependent vasodilation in a rabbit ischemic model through an increase in nitric oxide production. 相似文献149.
A submergence-induced gene, OsGGT, was cloned from 7-day submerged rice (Oryza sativa L. plants, FR13A (a submergence-tolerant cultivar, Indica), using suppression subtractive hybridization and both 5- and 3-rapid amplification of cDNA ends (RACE). The full-length OsGGT cDNA contains 1,273 bp with an open reading frame of 1,140 bp (17–1,156) that encodes 379 amino acids. Its deduced amino acid sequence is homologous with glycogenin glucosyltransferase. We found that the OsGGT gene is located in the 17,970–20,077 bp region of genome fragment AAAA01002475.1 of the Indica cultivar and in the 53,293–51,186 bp region of genome fragment AC037426.12 of chromosome 10 of the Japanica cultivar. A time-course study showed that OsGGT-gene expression increased in FR13A during submergence but decreased in IR42 (submergence-intolerant cultivar, Indica). The expression of the OsGGT gene in FR13A was induced by salicylic acid and benzyladenine. The accumulation of OsGGT mRNA in FR13A also increased in response to ethylene, gibberellin, abscisic acid, drought and salt treatment, but methyl jasmonate treatment and cold stress had no effect on expression. These results suggest that the OsGGT gene could be related to submergence stress and associated with a general defensive response to various environmental stresses.The nucleotide sequences of OsGGT cDNA has been submitted to GenBank DDBJ under accession numbers AB164463. 相似文献
150.
Papillomavirus capsid mutation to escape dendritic cell-dependent innate immunity in cervical cancer 下载免费PDF全文
Yang R Wheeler CM Chen X Uematsu S Takeda K Akira S Pastrana DV Viscidi RP Roden RB 《Journal of virology》2005,79(11):6741-6750
Infection with oncogenic human papillomaviruses (HPVs), typified by HPV type 16 (HPV16), is a necessary cause of cervical cancer. Prophylactic vaccination with HPV16 L1 virus-like particles (VLPs) provides immunity. HPV16 VLPs activate dendritic cells and a potent neutralizing immunoglobulin G (IgG) response, yet many cervical cancer patients fail to generate detectable VLP-specific IgG. Therefore, we examined the role of the innate recognition of HPV16 L1 in VLP-induced immune responses and its evasion during carcinogenesis. Nonconservative mutations within HPV16 L1 have been described in isolates from cervical cancer and its precursor, high-grade cervical intraepithelial neoplasia (CIN). We determined the effect of mutations in L1 upon in vitro self-assembly into VLPs and their influence upon the induction of innate and adaptive immune responses in mice. Several nonconservative mutations in HPV16 L1 isolated from high-grade CIN or cervical carcinoma prevent self-assembly of L1 VLPs. Intact VLPs, but not assembly-defective L1, activate dendritic cells to produce proinflammatory factors, such as alpha interferon, that play a critical role in inducing adaptive immunity. Indeed, effective induction of L1-specific IgG1 and IgG2a was dependent upon intact VLP structure. Dendritic cell activation and production of virus-specific neutralizing IgG by VLPs requires MyD88-dependent signaling, although the L1 structure that initiates MyD88-mediated signaling is distinct from the neutralizing epitopes. We conclude that innate recognition of the intact L1 VLP structure via MyD88 is critical in the induction of high-titer neutralizing IgG. Tumor progression is associated with genetic instability and L1 mutants. Selection for assembly-deficient L1 mutations suggests the evasion of MyD88-dependent immune control during cervical carcinogenesis. 相似文献