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排序方式: 共有558条查询结果,搜索用时 24 毫秒
1.
Takaharu Negoro Kanami Orihara Tomoko Irahara Hiroshi Nishiyama Kanae Hagiwara Risa Nishida Hiroki Takagi Kazue Satoh Yoshiki Yamamoto Shunichi Shimizu Tamio Hagiwara Masakazu Ishii Toshihiro Tanioka Yasuko Nakano Ken Takeda Isao Yoshimura Yoji Iikura Takashi Tobe 《Pediatric allergy and immunology》2006,17(8):583-590
Although many single nucleotide polymorphism (SNP) studies have reported an association of atopy, allergic diseases and total serum immunoglobulin E (IgE) levels, almost all of these studies sought risk factors for the onset of these allergic diseases. Furthermore, many studies have analyzed a single gene and hardly any have analyzed environmental factors. In these analyses, the results could be masked and the effects of other genes and environmental factors may be decreased. Here, we described the correlation between four genes [interleukin (IL)-4 (C-590T), IL-4 receptor (A1652G), FCER1B (G6842A) and STAT6 (G2964A)] in connection with IgE production; the role of IL-10 (C-627A) as a regulatory cytokine of allergy; and the severity of food allergy (FA) and atopic eczema (AE) in 220 Japanese allergic children. In addition to these SNPs, environmental factors, i.e., patient's attitude, indoor environment, and so on, were also investigated in this study. Our study was retrospective, and the correlation was analyzed by our defined clinical scores divided into three terms: worst symptoms, recent symptoms and general amelioration at the most recent examination during the disease course. Our results indicated that IL-10 AA, the genotype with lower IL-10 production, is associated with higher IgE levels in the serum (p < 0.0001, estimate; 0.912). Marginal liver abnormalities were observed in the subject group with both FA and AE (p < 0.1191, estimate; 0.1490). Our defined clinical scores enabled evaluation of various aspects of disease severity. Based on the scores, while no single SNP selected in this study determined severity, the combination of the SNP with laboratory data and environmental factors appeared to determine severity. 相似文献
2.
Kurata H Shimizu N Misumi K 《Genome informatics. International Conference on Genome Informatics》2004,15(2):161-170
A goal of systems biology is to build a concrete biochemical network map, which provides an important instruction to trace the pathways of interest or to understand the mechanism of a biological system. In the postgenomic era, not only the concrete biochemical maps, but also postgenomic maps (mRNA coexpression and protein-protein interaction networks) have been extensively produced. In the biochemical map, the individual reactions are reliable, but the number of the reactions is limited, because molecular biology requires extensive experiments to verify them. By contrast, postgenomic data provide much information regarding interactions, but are coarse-grained. To expand the biochemical network, an intuitional approach, which superposes postgenomic data on the map one by one, has been carried out, but it is not effective when a large amount of the coarse-grained data is handled. In order to effectively integrate such postgenomic interactions into a biochemical map, a statistical approach would be suitable rather than intuition. In this article, we proposed a novel statistical approach that integrates postgenomic interaction networks into the biochemical network, predicting novel pathways. A statistical correlation for such different types of networks identifies functional modules; subsequently the superposition of the different networks on the functional modules predicts inter-modular relations, which are the key pathways to construct a large-scale biochemical network. 相似文献
3.
Delta-like 1 is necessary for the generation of marginal zone B cells but not T cells in vivo 总被引:11,自引:0,他引:11
Hozumi K Negishi N Suzuki D Abe N Sotomaru Y Tamaoki N Mailhos C Ish-Horowicz D Habu S Owen MJ 《Nature immunology》2004,5(6):638-644
Notch receptors and their ligands contribute to many developmental systems, but it is not apparent how they function after birth, as their null mutants develop severe defects during embryogenesis. Here we used the Cre-loxP system to delete the Delta-like 1 gene (Dll1) after birth and demonstrated the complete disappearance of splenic marginal zone B cells in Dll1-null mice. In contrast, T cell development was unaffected. These results demonstrated that Dll1 was dispensable as a ligand for Notch1 at the branch point of T cell-B cell development but was essential for the generation of marginal zone B cells. Thus, Notch signaling is essential for lymphocyte development in vivo, but there is a redundancy of Notch-Notch ligand signaling that can drive T cell development within the thymus. 相似文献
4.
Kouya Hattori Masahiro Akiyama Natsumi Seki Kyosuke Yakabe Koji Hase Yun-Gi Kim 《Nutrients》2021,13(6)
While poorly-absorbed sugar alcohols such as sorbitol are widely used as sweeteners, they may induce diarrhea in some individuals. However, the factors which determine an individual’s susceptibility to sugar alcohol-induced diarrhea remain unknown. Here, we show that specific gut bacteria are involved in the suppression of sorbitol-induced diarrhea. Based on 16S rDNA analysis, the abundance of Enterobacteriaceae bacteria increased in response to sorbitol consumption. We found that Escherichia coli of the family Enterobacteriaceae degraded sorbitol and suppressed sorbitol-induced diarrhea. Finally, we showed that the metabolism of sorbitol by the E. coli sugar phosphotransferase system helped suppress sorbitol-induced diarrhea. Therefore, gut microbiota prevented sugar alcohol-induced diarrhea by degrading sorbitol in the gut. The identification of the gut bacteria which respond to and degrade sugar alcohols in the intestine has implications for microbiome science, processed food science, and public health. 相似文献
5.
Yuri Takahashi Yasuo Miyoshi Chie Takahata Natsumi Irahara Tetsuya Taguchi Yasuhiro Tamaki Shinzaburo Noguchi 《Clinical cancer research》2005,11(4):1380-1385
PURPOSE: LATS1 and LATS2 are tumor suppressor genes implicated in the regulation of cell cycle. Methylation status of the promoter regions of these genes as well as its correlation with their mRNA levels were studied in human breast cancers. Correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics of breast tumors were also studied. EXPERIMENTAL DESIGN: Methylation status of promoter regions of LATS1 and LATS2 was studied by a methylation-specific PCR and mRNA expression levels of LATS1 and LATS2 were determined by a real-time PCR assay in 30 breast cancers. In addition, correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics was studied in 117 breast cancers. RESULTS: Methylation-specific PCR showed that of 30 tumors, LATS1 promoter region was hypermethylated in 17 tumors (56.7%) and LATS2 promoter region was hypermethylated in 15 (50.0%) tumors. LATS1 mRNA levels in breast tumors with hypermethylation (2.15 +/- 0.37, mean +/- SE) were significantly (P < 0.01) lower than those without hypermethylation (6.09 +/- 1.38), and LATS2 mRNA levels in breast tumors with hypermethylation (1.42 +/- 0.66) were also significantly (P < 0.01) lower than those without hypermethylation (3.10 +/- 1.00). The decreased expression of LATS1 or LATS2 mRNA was significantly associated with a large tumor size, high lymph node metastasis, and estrogen receptor and progesterone receptor negativity. Furthermore, the decreased expression of LATS1 mRNA, but not LATS2 mRNA, was significantly (P < 0.05) associated with a poor prognosis. CONCLUSIONS: Hypermethylation of the promoter regions of LATS1 and LATS2 likely plays an important role in the down-regulation of their mRNA levels in breast cancers, and breast cancers with a decreased expression of LATS1 or LATS2 mRNA levels have a biologically aggressive phenotype. 相似文献
6.
Ron Firestein Kaori Shima Katsuhiko Nosho Natsumi Irahara Yoshifumi Baba Emeric Bojarski Edward L. Giovannucci William C. Hahn Charles S. Fuchs Shuji Ogino 《International journal of cancer. Journal international du cancer》2010,126(12):2863-2873
Alterations in the Wnt/β‐catenin pathway define a key event in the pathogenesis of colon cancer. We have recently shown that CDK8, the gene encoding a cyclin‐dependent kinase (CDK) component of the Mediator complex, acts as a colon cancer oncogene that is necessary for β‐catenin activity. Here, we tested the hypothesis that colorectal cancers with CDK8 expression have distinct clinical, prognostic and molecular attributes. Among 470 colorectal cancers identified in 2 prospective cohort studies, CDK8 expression was detected in 329 (70%) tumors by immunohistochemistry. Cox proportional hazards model and backward stepwise elimination were used to compute hazard ratio (HR) of deaths according to CDK8 status, initially adjusted for various patient and molecular features, including β‐catenin, p53, p21, p27 (CDK inhibitors), cyclin D1, fatty acid synthase (FASN), cyclooxygenase‐2 (COX‐2), microsatellite instability (MSI), CpG island methylator phenotype (CIMP), LINE‐1 methylation, and mutations in KRAS, BRAF and PIK3CA. CDK8 expression in colorectal cancer was independently associated with β‐catenin activation (p = 0.0002), female gender (p < 0.0001) and FASN overexpression (p = 0.0003). Among colon cancer patients, CDK8 expression significantly increased colon cancer‐specific mortality in both univariate analysis [HR 1.70; 95% confidence interval (CI), 1.03–2.83; p = 0.039] and multivariate analysis (adjusted HR 2.05; 95% CI, 1.18–3.56; p = 0.011) that was adjusted for potential confounders including β‐catenin, COX‐2, FASN, LINE‐1 hypomethylation, CIMP and MSI. CDK8 expression was unrelated with clinical outcome among rectal cancer patients. These data support a potential link between CDK8 and β‐catenin, and suggest that CDK8 may identify a subset of colon cancer patients with a poor prognosis. 相似文献
7.
Kazuki Numajiri Natsumi Matsuura Hitoshi Igai Fumi Ohsawa Mitsuhiro Kamiyoshihara 《Journal of thoracic disease》2022,14(8):2908
BackgroundAlthough video-assisted thoracoscopic surgery (VATS) segmentectomy has become widespread, the advantage of uniportal VATS (U-VATS) segmentectomy over multiportal VATS (M-VATS) remains controversial. The purpose of this study was to verify the safety and usefulness of U-VATS segmentectomy compared with conventional hybrid/multiportal segmentectomy.MethodsHere, we retrospectively reviewed the data from anatomical pulmonary segmentectomy cases in a single institution from March 2010 to March 2021. Patients were divided into the U-VATS and hybrid/multiportal VATS (H/M-VATS) groups. Perioperative results were compared between the groups after matching for patient background characteristics. In addition, cases of complex segmentectomy were selected from each group and compared in terms of perioperative results.ResultsA total of 180 patients underwent pulmonary segmentectomy during the study period at this institution, comprising 57 cases in the U-VATS group and 123 cases in the H/M-VATS group. After matching for age, sex, disease, tumor location, and type of segmentectomy, no significant differences between the groups were seen in blood loss, major intraoperative bleeding, rate of conversion to thoracotomy, postoperative complications, or re-hospitalization within 30 days after discharge. Operation time (141±46 vs. 174±45 min, P<0.001), postoperative drainage duration (1.5±1.2 vs. 2.3±1.8 days, P=0.007), and postoperative hospital stay (3.4±2.0 vs. 4.6±2.5 days, P=0.006) were significantly lower in the U-VATS group. Subgroup analysis of the complex segmentectomy cases also revealed that operation time (146±34 vs. 185±47 min, P<0.001), postoperative drainage duration (1.5±1.3 vs. 2.2±1.2 days, P=0.021), and postoperative hospital stay (3.0±1.4 vs. 4.9±2.1 days, P<0.001) were significantly reduced in the U-VATS group.ConclusionsU-VATS segmentectomy appears as safe and feasible as H/M-VATS segmentectomy. An experienced surgeon can make a smooth transition to U-VATS. 相似文献
8.
Pilot study of the optimal protocol of low dose step‐up follicle stimulating hormone therapy for infertile women
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Toshiya Matsuzaki Takeshi Iwasa Rie Yanagihara Mizuki Komasaka Kiyohito Yano Yiliyasi Mayila Ayaka Tachibana Yuri Yamamoto Takeshi Kato Akira Kuwahara Minoru Irahara 《Reproductive Medicine and Biology》2018,17(3):315-324
Purpose
To evaluate the optimized protocol of low dose follicle‐stimulating hormone (FSH) therapy that has a starting dose of 50 IU/62.5 IU with a small increment dose (12.5 IU) for women with World Health Organization (WHO) II ovulatory disorder and unexplained infertility.Methods
Anovulatory women with WHO group II ovulatory disorder (ovulation induction [OI] patients, n = 29), and with an unexplained infertility (ovarian stimulation [OS] patients, n = 21) were enrolled. The protocol of low dose step‐up FSH therapy was optimized for the starting dose as 50 IU (body mass index [BMI] < 20 group) and 62.5 IU (BMI ≥ 20 group) with the increment dose of 12.5 IU. Study outcomes were ovulation, monofollicular development and other variables.Results
In the OIpatients, the ovulation rate was 100% (BMI < 20 group) and 90.9% (BMI ≥ 20 group). Monofollicular development was 80.0% (BMI < 20) and 77.3% (BMI ≥ 20). The pregnancy rate was 60% (3/5 BMI < 20) and 18.2% (4/22 BMI ≥ 20). There was no multiple pregnancy. In the OSpatients, the ovulation rate was 100%. Monofollicular development was 85.7% (BMI < 20) and 76.6% (BMI ≥ 20). No pregnancy was achieved in the OSpatients.Conclusion
Optimized protocol of low dose FSH therapy setting a starting dose 50 IU/62.5 IU by BMI with an increment dose of 12.5 IU was safe and highly effective in WHO group II anovulatory patients. However, this protocol seemed uneffective for patients with unexplained infertility. 相似文献9.
10.