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71.
Higashikata T Yamagishi M Sasaki H Minatoya K Ogino H Ishibashi-Ueda H Hao H Nagaya N Tomoike H Sakamoto A 《Atherosclerosis》2004,177(2):353-360
BACKGROUND: The relative expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), key regulators in remodeling of extracellular matrix, are considered to play a pivotal role in the development of abdominal aortic aneurysm (AAA). However, few data exist regarding quantitative assessment of their expression in clinical settings. METHODS: In 22 patients with AAA who underwent graft replacement, tissue samples of the AAA and non-dilated aorta were obtained. Using a real-time RT-PCR method that enabled quantitative measurement of mRNA levels in small tissue samples, we determined gene expression levels of MMPs and TIMPs relative to that of glutaraldehyde 3-phosphate dehydrogenase in each sample. RESULTS: The expression levels of the MMP-1 and -3 genes were significantly augmented in AAA compared with non-dilated regions (4.48 +/- 2.01 versus 0.26 +/- 0.12, P < 0.01 and 1.89 +/- 1.00 versus 5.01 +/- 0.97, P < 0.05, respectively). Although genes for TIMP-1, -2 and -3 tended to be upregulated in AAA, relative expression levels of MMP-1 to TIMP-1, MMP-1 to TIMP-2, MMP-1 to TIMP-3, and MMP-3 to TIMP-2 were still higher in AAA than in non-dilated regions (1.12 +/- 0.63 versus 0.10 +/- 0.03, 4.13 +/- 1.12 versus 0.43 +/- 0.11, 1.61 +/- 0.59 versus 0.14 +/- 0.03, and 7.81 +/- 1.60 versus 2.56 +/- 0.76, respectively, P < 0.05). CONCLUSION: These results demonstrate that the present real-time RT-PCR method is reliable for the determination of mRNA levels in small samples of vascular tissue and that disproportional expression of both MMP-1 and MMP-3 relative to TIMPs relates pathologically to the evolution of AAA. 相似文献
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Kazutoyo Yoda Kenji Miyazawa Masataka Hosoda Masaru Hiramatsu Fang Yan Fang He 《European journal of nutrition》2014,53(1):105-115
Background
Fermented milk is considered one of the best sources for efficient consumption of probiotic strains by hosts to promote good health. The purpose of this study was to investigate the effects of orally administering LGG-fermented milk (LGG milk) on intestinal inflammation and injury and to study the mechanisms of LGG milk’s action.Methods
LGG milk and non-LGG-fermented milk (non-LGG milk) were administered through gavage to mice before and during dextran sodium sulfate (DSS)-induced intestinal injury and colitis. Inflammatory/injury score and colon length were assessed. Intestinal epithelial cells were treated with the soluble fraction of LGG milk to detect its effects on the epidermal growth factor receptor (EGFR) and its downstream target, Akt activation, cytokine-induced apoptosis, and hydrogen peroxide (H2O2)-induced disruption of tight junctions.Results
LGG milk treatment significantly reduced DSS-induced colonic inflammation and injury, and colon shortening in mice, compared to that in non-LGG milk-treated and -untreated mice. The soluble fraction of LGG milk, but not non-LGG milk, stimulated the activation of EGFR and Akt in a concentration-dependent manner, suppressed cytokine-induced apoptosis, and attenuated H2O2-induced disruption of tight junction complex in the intestinal epithelial cells. These effects of LGG milk were blocked by the EGFR kinase inhibitor. LGG milk, but not non-LGG milk, contained two soluble proteins, p40 and p75, that have been reported to promote survival and growth of intestinal epithelial cells through the activation of EGFR. Depletion of p40 and p75 from LGG milk abolished the effects of LGG milk on prevention of cytokine-induced apoptosis and H2O2-induced disruption of tight junctions.Conclusions
These results suggest that LGG milk may regulate intestinal epithelial homeostasis and potentially prevent intestinal inflammatory diseases through activation of EGFR by LGG-derived proteins. 相似文献74.
Hitoshi Uchiyama Masayuki Tsujimoto Tadakazu Shinmoto Hitomi Ogino Tomoko Oda Takuya Yoshida Taku Furukubo Satoshi Izumi Tomoyuki Yamakawa Hidehisa Tachiki Tetsuya Minegaki Kohshi Nishiguchi 《Toxins》2014,6(9):2612-2625
The risk of myopathy and rhabdomyolysis is considerably increased in statin users with end-stage renal failure (ESRF). Uremic toxins, which accumulate in patients with ESRF, exert cytotoxic effects that are mediated by various mechanisms. Therefore, accumulation of uremic toxins might increase statin-induced cytotoxicity. The purpose of this study was to determine the effect of four uremic toxins—hippuric acid, 3-carboxy-4-methyl-5-propyl-2-furanpropionate, indole-3-acetic acid, and 3-indoxyl sulfate—on statin-induced myopathy. Differentiated rhabdomyosarcoma cells were pre-treated with the uremic toxins for seven days, and then the cells were treated with pravastatin or simvastatin. Cell viability and apoptosis were assessed by viability assays and flow cytometry. Pre-treatment with uremic toxins increased statin- but not cisplatin-induced cytotoxicity (p < 0.05 vs. untreated). In addition, the pre-treatment increased statin-induced apoptosis, which is one of the cytotoxic factors (p < 0.05 vs. untreated). However, mevalonate, farnesol, and geranylgeraniol reversed the effects of uremic toxins and lowered statin-induced cytotoxicity (p < 0.05 vs. untreated). These results demonstrate that uremic toxins enhance statin-induced apoptosis and cytotoxicity. The mechanism underlying this effect might be associated with small G-protein geranylgeranylation. In conclusion, the increased severity of statin-induced rhabdomyolysis in patients with ESRF is likely due to the accumulation of uremic toxins. 相似文献
75.
Identification of novel candidate gene loci and increased sex chromosome aneuploidy among infants with conotruncal heart defects 下载免费PDF全文
76.
Natsuko Inazawa Naoki Hatakeyama Tsukasa Hori Masaki Yamamoto Keita Igarashi Hasegawa Tadashi Jiro Ogino Hiroyuki Tsutsumi Nobuhiro Suzuki 《Pediatrics international》2014,56(1):122-125
Neuroblastoma is a malignant tumor predominantly occurring in children and usually arising from the adrenal gland or sympathetic ganglia. We describe a neuroblastoma in a 1‐month‐old boy arising from his left orbital cavity. This tumor was refractory to chemotherapy or radiotherapy, requiring enucleation of the left eye for complete removal of the intraorbital tumor. Thereafter, he received high‐dose chemotherapy followed by autologous peripheral blood stem cell transplantation, and has been in complete remission for 3 years. Unlike neuroblastomas arising from the adrenal gland or sympathetic ganglia, primary orbital neuroblastoma may be refractory even in early infancy. 相似文献
77.
Ying-Bo Lu Shinji Kanehashi Kazushi Minegishi Shu-Ping Wang Jin Cheng Kenji Ogino Shijun Li 《RSC advances》2021,11(53):33431
Triphenylamine derivates have been utilized as building blocks in hole-transporting materials. Herein, we describe the synthesis of three octyl-derived conjugated triphenylamine macrocycles with different sizes, and a 4-(2-ethylhexyloxy)-substituted cyclic triphenylamine hexamer using a palladium-catalyzed C–N coupling reaction. These conjugated triphenylamine macrocycles not only have interesting structures, but also are capable of complexing with C60, C70 and PC61BM. Their binding stoichiometries with fullerenes were all determined to be 1 : 1 by an emission titration method. The association constants of these complexes were measured to be in the range of 0.115–1.53 × 105 M−1 depending on the cavity size of the triphenylamine macrocycles and the volume of the fullerenes. The space-charge-limited current properties of the complexes were further investigated using the fabricated ITO/PEDOT:PSS/active layer/Au devices.Cyclic triphenylamine (TPA) oligomers synthesized by C–N coupling were found to be capable of complexing with fullerenes, and the applications in optoelectronic devices were investigated by using the fabricated ITO/PEDOT:PSS/active layer/Au devices. 相似文献
78.
79.
80.
Hiroshi Saeki Yasushi Toh Masaru Morita Masahiko Sugiyama Kazutoyo Morita Yasuo Sakamoto Yuji Soejima Kazuhito Minami Yoshihisa Sakaguchi Yuichiro Higaki Satoru Uehara Takeshi Okamura Yoshihiko Maehara 《Esophagus》2012,9(3):158-164