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排序方式: 共有1968条查询结果,搜索用时 11 毫秒
101.
Relationship between coronary artery remodeling and plaque composition in culprit lesions: an intravascular ultrasound radiofrequency analysis. 总被引:1,自引:0,他引:1
Yasutomi Higashikuni Kengo Tanabe Hirosada Yamamoto Jiro Aoki Gaku Nakazawa Yoshinobu Onuma Shuji Otsuki Atsuhiko Yagishita Sen Yachi Hiroyoshi Nakajima Kazuhiro Hara 《Circulation journal》2007,71(5):654-660
BACKGROUND: The relationship between coronary artery remodeling and culprit plaque composition in vivo has not been fully evaluated by spectral analysis of intravascular ultrasound (IVUS) radiofrequency (RF) data. METHODS AND RESULTS: IVUS RF analyses were performed for 56 consecutive de novo culprit lesions of 52 patients undergoing percutaneous coronary intervention. Remodeling of culprit lesions was determined using the remodeling index (RI), calculated as the external elastic membrane area of the minimum lumen area (MLA) site divided by that of the proximal reference site. Positive remodeling was defined as RI >1.05, intermediate remodeling as 0.95< or = RI < or =1.05 and negative remodeling as RI <0.95. Among the 56 lesions, positive remodeling was detected in 24, intermediate remodeling in 16, and negative remodeling in 16. At MLA sites, positive remodeling lesions had a larger percentage of the fibrofatty component than negative remodeling lesions (22.5+/-10.3% vs 10.4+/-6.6%, p=0.0001), whereas the latter contained a larger percentage of the dense calcium component than the former (2.8+/-2.9% vs 8.4+/-7.0%, p=0.016). CONCLUSIONS: Culprit plaques with positive remodeling have a large lipid burden, whereas those with negative remodeling contain a large amount of calcium. 相似文献
102.
Masakazu Nakano Yoko Ikeda Takazumi Taniguchi Tomohito Yagi Masahiro Fuwa Natsue Omi Yuichi Tokuda Masami Tanaka Kengo Yoshii Masaaki Kageyama Shigeta Naruse Akira Matsuda Kazuhiko Mori Shigeru Kinoshita Kei Tashiro 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(31):12838-12842
Primary open-angle glaucoma (POAG) is the major type of glaucoma. To discover genetic markers associated with POAG, we examined a total of 1,575 Japanese subjects in a genome-wide association study (stage 1) and a subsequent study (stage 2). Both studies were carried out at a single institution. In the stage 1 association study, we compared SNPs between 418 POAG patients and 300 control subjects. First, low-quality data were eliminated by a stringent filter, and 331,838 autosomal SNPs were selected for analysis. Poorly clustered SNPs were eliminated by a visual assessment, leaving 255 that showed a significant deviation (P < 0.001) in the allele frequency comparison. In the stage 2 analysis, we tested these 255 SNPs for association in DNA samples from a separate group of 409 POAG and 448 control subjects. High-quality genotype data were selected and used to calculate the combined P values of stages 1 and 2 by the Mantel–Haenszel test. These analyses yielded 6 SNPs with P < 0.0001. All 6 SNPs showed a significant association (P < 0.05) in stage 2, demonstrating a confirmed association with POAG. Although we could not link the SNPs to the annotated gene(s), it turned out that we have identified 3 genetic loci probably associated with POAG. These findings would provide the foundation for future studies to build on, such as for the metaanalysis, to reveal the molecular mechanism of the POAG pathogenesis. 相似文献
103.
Rintaro Noro Kazufumi Honda Kengo Nagashima Noriko Motoi Shinobu Kunugi Jun Matsubayashi Susumu Takeuchi Hideaki Shiraishi Tetsuya Okano Ayumi Kashiro Xue Meng Yukihiro Yoshida Shunichi Watanabe Jitsuo Usuda Tatsuya Inoue Huang Wilber Norihiko Ikeda Masahiro Seike Akihiko Gemma Kaoru Kubota 《Cancer science》2022,113(3):1002
Although adjuvant tegafur/uracil (UFT) is recommended for patients with completely resected stage I non‐small‐cell lung cancer (NSCLC) in Japan, only one‐third of cases has received adjuvant chemotherapy (ADJ) according to real‐world data. Therefore, robust predictive biomarkers for selecting ADJ or observation (OBS) without ADJ are needed. Patients who underwent complete resection of stage I lung adenocarcinoma with or without adjuvant UFT were enrolled. The status of ACTN4 gene amplification was analyzed by FISH. Statistical analyses to determine whether the status of ACTN4 gene amplification affected recurrence‐free survival (RFS) were carried out. Formalin‐fixed, paraffin‐embedded samples from 1136 lung adenocarcinomas were submitted for analysis of ACTN4 gene amplification. Ninety‐nine (8.9%) of 1114 cases were positive for ACTN4 gene amplification. In the subgroup analysis of patients aged 65 years or older, the ADJ group had better RFS than the OBS group in the ACTN4‐positive cohort (hazard ratio [HR], 0.084, 95% confidence interval [CI], 0.009‐0.806; P = .032). The difference in RFS between the ADJ group and the OBS group was not significant in ACTN4‐negative cases (all ages: HR, 1.214; 95% CI, 0.848‐1.738; P = .289). Analyses of ACTN4 gene amplification contributed to the decision regarding postoperative ADJ for stage I lung adenocarcinomas, preventing recurrence, improving the quality of medical care, preventing the unnecessary side‐effects of ADJ, and saving medical costs. 相似文献
104.
Yoshihide Kanno MD Dai Hirasawa MD Naotaka Fujita MD Yutaka Noda MD Go Kobayashi MD Kazuhiko Ishida MD Kei Ito MD Takashi Obana MD Takashi Suzuki MD Toshiki Sugawara MD Jun Horaguchi MD Osamu Takasawa MD Kazunari Nakahara MD Tetsuya Ohira MD Kengo Onochi MD Yoshihiro Harada MD Wataru Iwai MD Masatake Kuroha MD 《Gastrointestinal endoscopy》2009,69(7):1363-1368
105.
Masashi Takao Yoshitsugu Oohata Kengo Kitadokoro Kumiko Kobayashi Shigenori Iwai Akira Yasui Shuji Yonei Qiu-Mei Zhang 《Genes to cells : devoted to molecular & cellular mechanisms》2009,14(2):261-270
Oxidative base damage leads to alteration of genomic information and is implicated as a cause of aging and carcinogenesis. To combat oxidative damage to DNA, cells contain several DNA glycosylases including OGG1, NTH1 and the Nei-like proteins, NEIL1 and NEIL2. A third Nei-like protein, NEIL3, is composed of an amino-terminal Nei-like domain and an unknown carboxy-terminal domain. In contrast to the other well-described DNA glycosylases, the DNA glycosylase activity and in vivo repair function of NEIL3 remains unclear. We show here that the structural modeling of the putative NEIL3 glycosylase domain (1–290) fits well to the known Escherichia coli Fpg crystal structure. In spite of the structural similarity, the recombinant NEIL3 and NEIL3(1–290) proteins do not cleave any of several test oligonucleotides containing a single modified base. Within the substrates, we detected AP lyase activity for single-stranded (ss) DNA but double-stranded (ds) DNA. The activity is abrogated completely in mutants with an amino-terminal deletion and at the zinc-finger motif. Surprisingly, NEIL3 partially rescues an E. coli nth nei mutant from hydrogen peroxide sensitivity. Taken together, repair of certain base damage including base loss in ssDNA may be mediated by NEIL3. 相似文献
106.
107.
Nakano M Kishida R Funakoshi K Tsukagoshi M Goris RC Kadota T Atobe Y Hisajima T 《The Journal of comparative neurology》2003,456(4):321-337
The central and peripheral organization of thoracic visceral and somatic nervous elements was studied by applying dextran amines to the proximal cut ends of the thoracic splanchnic and somatic nerves in Xenopus laevis. Many labeled dorsal root ganglion cells of visceral afferents, and all somatic afferents, were located in a single ganglion of one spinal segment, and the two types of cells were distributed topographically within the ganglion. The labeled sympathetic preganglionic neurons were located predominantly in the same area of the thoracic spinal gray as in other frogs and in mammals. The labeled visceral afferents projected to Lissauer's tract and the dorsal funiculus. The visceral fibers of the tract ascended to the level of the subcerebellar area, supplying collateral branches to the lateral one-third of the dorsal horn and to the area of brainstem nuclei, including lateral cervical and descending trigeminal nucleus, and descended to the filum terminale. The visceral fibers of the dorsal funiculus were distributed to the dorsal column nucleus and the solitary tract. A similar longitudinal projection was also seen in the somatic afferents. The dual central pathway of thoracic primary afferents in the anuran spinal cord is a property held in common with mammals, but the widespread rostrocaudal projection through Lissauer's tract may be a characteristic of the anuran central nervous system. In frogs, the direct transmission of primary afferent information to an extremely wide area of the central nervous system may be important for prompt assessment of environmental factors and control of body functions. 相似文献
108.
109.
Harada N Nishiyama S Ohba H Sato K Kakiuchi T Tsukada H 《Synapse (New York, N.Y.)》2002,44(3):139-145
The present study demonstrated the age-related changes in the striatal dopamine D1 receptor binding and its related cAMP second-messenger system in the living brains of conscious young (6.4 +/- 1.8 years old) and aged (19.5 +/- 3.3 years old) monkeys (Macaca mulatta) using positron emission tomography (PET). For quantitative analysis of D1 receptors, [11C]SCH23390 was used and phosphodiesterase type-IV (PDE-IV) activity, as an index of cAMP system, was estimated by two scans with R- and S-[11C]rolipram. Significant age-related decreases in D1 receptor binding were observed in the striatum and frontal cortex. Analysis of uptake of R- and S-[11C]rolipram indicated age-related decreases in PDE-IV activity showing 22.0 and 25.2% decreases in the striatum and frontal cortex, respectively, while no significant changes were observed in the cerebellum. With systemic preadministration of the dopamine D1 receptor antagonist SCH23390 (0.2, 0.6, and 2 mg/kg), the PDE-IV activities in the striatum and frontal cortex were dose-dependently suppressed in both age groups. However, the degree of suppression by SCH23390 was more marked in young than in aged monkeys. These results demonstrate that the striatal cAMP second-messenger system activity as well as its functional response to dopamine D1 antagonist showed age-related impairment in the brain. 相似文献
110.
Terada K Tamiya T Daido S Kambara H Tanaka H Ono Y Matsumoto K Ito S Ouchida M Ohmoto T Shimizu K 《Journal of neuro-oncology》2002,58(2):107-114
We thoroughly examined loss of heterozygosity (LOH) around three candidate tumor suppressor genes on chromosome 10q to determine whether LOH of each tumor suppressor gene is associated with the previously defined clinical prognostic indices. We also examined whether LOH can help predict prognostic variables in astrocytomas.We selected samples from 40 astrocytomas (grades 2–4), performed Ki-67 immunostaining, and counted positive cells. Using DNA from aliquots of tumor blocks and leukocytes, we investigated LOH around the PTEN, NEURL, and DMBT1 genes (10q23.3–26.1) with the silver staining procedure. We then statistically evaluated the relationship among histological features, regional LOH on chromosome 10q, and survival. The mean survival period for patients with LOH around PTEN was 7.2 months after surgery, while that for patients without LOH around PTEN was 21.4 months. Thus, LOH around PTEN was closely associated with a reduced overall survival (p = 0.0020) but LOH at NEURL or DMBT1 was not (p > 0.05).The combined features of an increase in histological grading and Ki-67-positive cells and the presence of LOH around PTEN significantly correlated with poor prognosis. These factors may be useful predictors of survival, and LOH analysis of tumor suppressor genes on chromosome 10q can contribute greatly to the treatment of patients with astrocytoma. 相似文献