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71.
72.
Hidetaka Sugihara Takatsugu Ishimoto Masayuki Watanabe Hiroshi Sawayama Masaaki Iwatsuki Yoshifumi Baba Yoshihiro Komohara Motohiro Takeya Hideo Baba 《PloS one》2013,8(11)
Bmi1 is overexpressed in a variety of human cancers including gastrointestinal cancer. The high expression level of Bmi1 protein is associated with poor prognosis of gastrointestinal cancer patients. On the other hand, tumor-associated macrophages (TAMs) contribute to tumor growth, invasion, and metastasis by producing various mediators in the tumor microenvironment. The aim of this study was to investigate TAM-mediated regulation of Bmi1 expression in gastrointestinal cancer. The relationship between TAMs and Bmi1 expression was analyzed by immunohistochemistry and quantitative real-time PCR (qRT-PCR), and results showed a positive correlation with tumor-infiltrating macrophages (CD68 and CD163) and Bmi1 expression in cancer cells. Co-culture with TAMs triggered Bmi1 expression in cancer cell lines and enhanced sphere formation ability. miRNA microarray analysis of a gastric cancer cell line co-cultured with macrophages was conducted, and using in silico methods to analyze the results, we identified miR-30e* as a potential regulator of Bmi1 expression. Luciferase assays using miR-30e* mimic revealed that Bmi1 was a direct target for miR-30e* by interactions with the putative miR-30e* binding sites in the Bmi1 3′ untranslated region. qRT-PCR analysis of resected cancer specimens showed that miR-30e* expression was downregulated in tumor regions compared with non-tumor regions, and Bmi1 expression was inversely correlated with miR-30e* expression in gastric cancer tissues, but not in colon cancer tissues. Our findings suggest that TAMs may cause increased Bmi1 expression through miR-30e* suppression, leading to tumor progression. The suppression of Bmi1 expression mediated by TAMs may thus represent a possible strategy as the treatment of gastrointestinal cancer. 相似文献
73.
Kenichi Tanaka Masaaki Nakayama Makoto Kanno Hiroshi Kimura Kimio Watanabe Yoshihiro Tani Yuki Kusano Hodaka Suzuki Yoshimitsu Hayashi Koichi Asahi Keiji Sato Toshio Miyata Tsuyoshi Watanabe 《PloS one》2013,8(12)
Background
Advanced glycation end product (AGE) accumulation is thought to be a measure of cumulative metabolic stress that has been reported to independently predict cardiovascular disease in diabetes and renal failure. The aim of this study was to evaluate the association between AGE accumulation, measured as skin autofluorescence, and the progression of renal disease in pre-dialysis patients with chronic kidney disease (CKD).Methods
Skin autofluorescence was measured noninvasively with an autofluorescence reader at baseline in 449 pre-dialysis patients with CKD. The primary end point was defined as a doubling of serum creatinine and/or need for dialysis.Results
Thirty-three patients were lost to follow-up. Forty six patients reached the primary end point during the follow-up period (Median 39 months). Kaplan-Meier analysis showed a significantly higher risk of development of the primary end points in patients with skin autofluorescence levels above the optimal cut-off level of 2.31 arbitrary units, derived by receiver operator curve analysis. Cox regression analysis revealed that skin autofluorescence was an independent predictor of the primary end point, even after adjustment for age, gender, smoking history, diabetes, estimated glomerular filtration rate and proteinuria (adjusted hazard ratio 2.58, P = 0.004).Conclusions
Tissue accumulation of AGEs, measured as skin autofluorescence, is a strong and independent predictor of progression of CKD. Skin autofluorescence may be useful for risk stratification in this group of patients; further studies should clarify whether AGE accumulation could be one of the therapeutic targets to improve the prognosis of CKD. 相似文献74.
Takashi Nobusawa Yoko Okushima Noriko Nagata Mikiko Kojima Hitoshi Sakakibara Masaaki Umeda 《PLoS biology》2013,11(4)
Plant organ growth is controlled by inter-cell-layer communication, which thus determines the overall size of the organism. The epidermal layer interfaces with the environment and participates in both driving and restricting growth via inter-cell-layer communication. However, it remains unknown whether the epidermis can send signals to internal tissue to limit cell proliferation in determinate growth. Very-long-chain fatty acids (VLCFAs) are synthesized in the epidermis and used in the formation of cuticular wax. Here we found that VLCFA synthesis in the epidermis is essential for proper development of Arabidopsis thaliana. Wild-type plants treated with a VLCFA synthesis inhibitor and pasticcino mutants with defects in VLCFA synthesis exhibited overproliferation of cells in the vasculature or in the rib zone of shoot apices. The decrease of VLCFA content increased the expression of IPT3, a key determinant of cytokinin biosynthesis in the vasculature, and, indeed, elevated cytokinin levels. These phenotypes were suppressed in ipt3;5;7 triple mutants, and also by vasculature-specific expression of cytokinin oxidase, which degrades active forms of cytokinin. Our results imply that VLCFA synthesis in the epidermis is required to suppress cytokinin biosynthesis in the vasculature, thus fine-tuning cell division activity in internal tissue, and therefore that shoot growth is controlled by the interaction between the surface (epidermis) and the axis (vasculature) of the plant body. 相似文献
75.
76.
Masaaki Konishi Seigo Sugiyama Koichi Sugamura Toshimitsu Nozaki Keisuke Ohba Junichi Matsubara Kenji Sakamoto Yasuhiro Nagayoshi Hitoshi Sumida Eiichi Akiyama Yasushi Matsuzawa Kentaro Sakamaki Satoshi Morita Kazuo Kimura Satoshi Umemura Hisao Ogawa 《PloS one》2013,8(4)
Background
Cardiac troponin is a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes. Troponin release from the coronary circulation remains to be determined because of the lower sensitivity of the conventional assay. We sought to determine basal and angina-induced troponin release using a highly sensitive troponin assay.Methods and Results
The cardiac troponin T levels in serum sampled from the peripheral vein (PV), the aortic root (AO), and the coronary sinus (CS) were measured in 105 consecutive stable patients with coronary risk factor(s) and suspected coronary artery disease (CAD) and in 33 patients without CAD who underwent an acetylcholine provocation test. At baseline, there was a significant increase in the troponin levels from AO [9.0 (6.4, 13.1) pg/mL for median (25th, 75th percentiles)] to CS [10.3 (7.3, 15.5) pg/mL, p<0.001] in 96 (91.4%) patients and the difference was 1.1 (0.4, 2.1) pg/mL, which reflected basal transcardiac troponin release (TTR). TTR was positively correlated with PV levels (r = 0.22, p = 0.03). Male sex, left ventricular hypertrophy determined by echocardiography, T-wave inversion, and CAD correlated with elevated TTR defined as above: median, 1.1 pg/mL. A significant increase in TTR was noted in 17 patients with coronary spasms [0.6 (0.2, 1.2) pg/mL, p<0.01] but not in 16 patients without spasms [0.0 (−0.5, 0.9) pg/mL, p = 0.73] after the acetylcholine provocation.Conclusion
Basal TTR in the coronary circulation was observed in most of the patients with suspected CAD and risk factor(s). This sensitive assay detected myocardial ischemia-induced increases in TTR caused by coronary spasms. 相似文献77.
78.
79.
Koichi Hirabayashi Masaaki Shiohara Kazuhiro Yamada Akane Sueki Yuichiro Ide Koichi Takeuchi Rokuro Hagimoto Tatsuya Kinoshita Akihiko Yabuhara S. Harvey Mudd Kenichi Koike 《Gene》2013
Background
There is not much information on established standard therapy for patients with severe methionine adenosyltransferase (MAT) I/III deficiency.Case presentation
We report a boy with MAT I/III deficiency, in whom plasma methionine and total homocysteine, and urinary homocystine were elevated. Molecular genetic studies showed him to have novel compound heterozygous mutations of the MAT1A gene: c.191T>A (p.M64K) and c.589delC (p.P197LfsX26). A low methionine milk diet was started at 31 days of age, and during continuing dietary methionine restriction plasma methionine levels have been maintained at less than 750 μmol/L. He is now 5 years old, and has had entirely normal physical growth and psychomotor development.Conclusions
Although some severely MAT I/III deficient patients have developed neurologic abnormalities, we report here the case of a boy who has remained neurologically and otherwise normal for 5 years during methionine restriction, suggesting that perhaps such management, started in early infancy, may help prevent neurological complications. 相似文献80.
Hirokazu Matsumoto Yumiko Shimizu Atsuko Tanaka Takuya Nogi Ichiro Tabuchi Kenji Oyama Masaaki Taniguchi Hideyuki Mannen Shinji Sasazaki 《Molecular biology reports》2013,40(4):3231-3237
Genetic analyses have contributed to improvements of economically important traits derived from adipose tissue such as fatty acid composition in beef. Elongation of very long chain fatty acids (ELOVL) genes encode for the enzymes that play an important role in elongation of long-chain fatty acids. In this study, we aimed to discover genetic polymorphisms of ELOVL gene family in cattle populations to develop genetic markers. As a result, five synonymous mutations were detected in the coding regions of the ELOVL1, ELOVL2, ELOVL3 and ELOVL5 genes. In addition, six mutations were identified in promoter region of the ELOVL5. Two of five mutations in the promoter region of ELOVL5 were expected to alter the ELOVL5 expression and influence the economic traits, because of the high synteny of the region which was essential for activation of Elovl5 in mouse. Therefore, we performed association analysis between the genotypes and traits and our result revealed that T allele of g.-110T>C in ELOVL5 gene promoter indicated significantly thinner subcutaneous fat thickness (TT, 2.39 cm; CT, 2.35 cm) than that of C allele (CC, 2.68 cm) in a Japanese Black population. Our results suggest that the g.-110T>C is a useful genetic marker for the breeding in beef cattle. 相似文献