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991.
Satoh T Tajima M Wakita D Kitamura H Nishimura T 《European journal of immunology》2012,42(9):2329-2342
The plasticity of T lymphocytes induced by epigenetic modifications of gene promoters may play a pivotal role in controlling their effector functions, which are sometimes causally associated with immune disorders. IL -17-producing T cells, which induce type 17 immune responses, are newly identified pathogenic effector cells. The type 1 signature cytokine IFN-γ strongly inhibits their differentiation, indicating a mutually exclusive relationship between type 17- and type 1-immune responses. However, many reports indicate the presence of a unique IL-17/IFN-γ-double producing T-cell subset in various inflammatory settings, although the mechanisms responsible for their development and their precise functions remain unclear. Here, we demonstrate that IL-12 permits the conversion of mouse IL-17-producing CD8(+) T (Tc17) cells to IL-17/IFN-γ-double producing CD8(+) T (Tc17/IFN-γ) cells, and that this conversion is due to repressive epigenetic modifications of Socs3 gene promoters. Moreover, we show that SOCS3 strongly regulates the capability of Tc17 cells to produce IL-17, in addition to regulating the expression of the type 17-master regulator RORγt. These findings elucidate the mechanisms underlying the conversion of Tc17 cells into Tc17/IFN-γ cells. As these cells are known to have potent antitumor activities, manipulation of these conversion mechanisms for therapeutic tumor immunity may be possible. 相似文献
992.
Tomoki Ushijima Yoshihisa Tanoue Takayuki Uchida Sho Matsuyama Takashi Matsumoto Ryuji Tominaga 《Journal of artificial organs》2014,17(3):250-257
The 16-mm ATS mechanical valve is one of the smallest prosthetic valves used for aortic valve replacement (AVR) in patients with a very small aortic annulus, and its clinical outcomes are reportedly satisfactory. Here, we analyzed the left ventricular (LV) performance after AVR with the 16-mm ATS mechanical valve, based on the concept of cardiac energetics analysis. Eleven patients who underwent AVR with the 16-mm ATS mechanical valve were enrolled in this study. All underwent echocardiographic examination at three time points: before AVR, approximately 1 month after AVR, and approximately 1 year after AVR. LV contractility (end-systolic elastance [Ees]), afterload (effective arterial elastance [Ea]), and efficiency (ventriculoarterial coupling [Ea/Ees] and the stroke work to pressure–volume area ratio [SW/PVA]) were noninvasively measured by echocardiographic data and blood pressure measurement. Ees transiently decreased after AVR and then recovered to the pre-AVR level at the one-year follow-up. Ea significantly decreased in a stepwise manner. Consequently, Ea/Ees and SW/PVA were also significantly improved at the one-year follow-up compared with those before AVR. The midterm LV performance after AVR with the 16-mm ATS mechanical valve was satisfactory. AVR with the 16-mm ATS mechanical valve is validated as an effective treatment for patients with a very small aortic annulus. The cardiac energetics variables, coupling with the conventional hemodynamic variables, can contribute to a better understanding of the patients’ clinical conditions, and those may serve as promising indices of the cardiac function. 相似文献
993.
Objective
Although radiotherapy is effective for head and neck cancer patients, the local pain evoked by the irradiation itself reduces food intake and frequently halts the treatment. Thus, pain control is an important problem in radiotherapy for head and neck cancer. We performed to examine whether early induction of low-dose, opioid from mild pain improves dietary and caloric intake, while reducing weight loss.Methods
The subjects were 43 patients who were hospitalized for head and neck cancer from 2004 to 2008. They were patients who underwent radiation treatment but those who did not undergo preoperative treatment. They were divided into two groups, depending on whether the pain was mild or moderate when an opioid was introduced (MILD and MODERATE, N = 23 and 20, respectively).Results
The visual analog scale scores for pain were significantly lower in the MILD than in the MODERATE group at between 25 and 50 Gy. The amount of oxycodone used for pain was significantly lower in the MILD than the MODERATE group. A regular diet was maintained for significantly longer in the MILD group. Caloric intake was significantly higher in the MILD group at over 20 Gy. Weight loss was significantly lower in the MILD group at over 20 Gy. The incidence of side effects was equal in both groups.Conclusion
Our results indicated that the introduction of opioids for mild pain during radiotherapy controls the level of pain, improving food intake in head and neck cancer patients. 相似文献994.
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996.
997.
Medet Jumabay Taro Matsumoto Shin-ichiro Yokoyama Koichiro Kano Yoshiaki Kusumi Takayuki Masuko Masako Mitsumata Satoshi Saito Atsushi Hirayama Hideo Mugishima Noboru Fukuda 《Journal of molecular and cellular cardiology》2009,47(5):565-575
Adipose tissue-derived stem cells have been demonstrated to differentiate into cardiomyocytes and vascular endothelial cells. Here we investigate whether mature adipocyte-derived dedifferentiated fat (DFAT) cells can differentiate to cardiomyocytes in vitro and in vivo by establishing DFAT cell lines via ceiling culture of mature adipocytes. DFAT cells were obtained by dedifferentiation of mature adipocytes from GFP-transgenic rats. We evaluated the differentiating ability of DFAT cells into cardiomyocytes by detection of the cardiac phenotype markers in immunocytochemical and RT-PCR analyses in vitro. We also examined effects of the transplantation of DFAT cells into the infarcted heart of rats on cardiomyocytes regeneration and angiogenesis. DFAT cells expressed cardiac phenotype markers when cocultured with cardiomyocytes and also when grown in MethoCult medium in the absence of cardiomyocytes, indicating that DFAT cells have the potential to differentiate to cardiomyocyte lineage. In a rat acute myocardial infarction model, transplanted DFAT cells were efficiently accumulated in infarcted myocardium and expressed cardiac sarcomeric actin at 8 weeks after the cell transplantation. The transplantation of DFAT cells significantly (p < 0.05) increased capillary density in the infarcted area when compared with hearts from saline-injected control rats. We demonstrated that DFAT cells have the ability to differentiate to cardiomyocyte-like cells in vitro and in vivo. In addition, transplantation of DFAT cells led to neovascuralization in rats with myocardial infarction. We propose that DFAT cells represent a promising candidate cell source for cardiomyocyte regeneration in severe ischemic heart disease. 相似文献
998.
Takayuki Ohwada Toshiyuki Ishibashi Hiroyuki Yaoita Joji Shindo Hideyoshi Noji Hiroyuki Ohkawara Kouichi Sugimoto Takayuki Sakamoto Kazuhira Maehara Yukio Maruyama 《Circulation journal》2002,66(10):965-971
It remains to be clarified how angiotensin-converting enzyme inhibitor-induced function (ie, increased NO related action or the inhibition of angiotensin II AT1 receptor dependent action) affects apoptosis of smooth muscle cells in the neointima following arterial injury. Saline (control), enalapril, L-arginine, combined enalapril and L-arginine, or losartan was administered for 14 days to Sprague-Dawley rats after balloon carotid injury and the ratio of intima to media areas (I/M), inducible NO synthase (iNOS) concentrations and %TUNEL were measured. I/M decreased similarly in the enalapril, L-arginine and losartan groups, and the combination of enalapril and L-arginine resulted in the largest I/M decrease. TUNEL positivity was increased compared with controls in the following order: losartan, L-arginine, enalapril and combination of enalapril and L-arginine. The intensity of immunostaining for iNOS was increased approximately 1.9-fold compared with the control in the combined enarapril and L-arginine group as well as in the enalapril group. These data suggest that the apoptosis in the neointima is different for L-arginine, losartan and enalapril under similar conditions and was higher under treatment with enalapril, not only via the action of NO or blocking of the AT1, but also by upregulation of iNOS. 相似文献
999.
1000.
Lei Zhang Tetsu Yamane Eiji Satoh Kenichi Amagasaki Tomoyuki Kawataki Takayuki Asahara Koro Furuya Hideaki Nukui Hirofumi Naganuma 《Neuropathology》2005,25(2):136-143
Five malignant glioma cell lines (YMG1, 2, 3, 4, and 5) were established from surgical specimens obtained from patients with glioblastoma or anaplastic astrocytoma, and these lines were partially characterized. Three glioma cell lines (YMG1, 3, and 5) were weakly positive for GFAP by Western blot analysis and two cell lines were negative. S‐100 protein was positive in all glioma cell lines. The expression of p53, p16, p15, cyclin‐dependent kinase 4 (CDK4), and EGF receptor (EGFR) proteins was examined by Western blotting. YMG1 and 2 cell lines showed accumulation of p53 protein and loss of p16 and p15 expression. YMG3 and 4 showed accumulation of p53 protein and expression of p16 and p15 proteins. YMG5 revealed weak expression of p53 protein, suggesting wild‐type p53, and loss of p16 and p15 expression. All cell lines expressed various levels of CDK4 protein. YMG1, 2, and 3 showed higher EGFR protein expression and YMG4 and 5 showed lower EGFR expression compared to U251 glioblastoma cells, which express high levels of EGFR. Fluorescence in situ hybridization analysis for EGFR gene expression did not show any amplification in the glioma cell lines. Immunohistochemical studies revealed that the patterns of p53 and EGFR expressions in the original tumor tissues were mostly correlated with those in the malignant glioma cell lines. These results suggest that the characteristics of p53 and EGFR expression in the malignant glioma cell lines were passed over from the original tumor tissues. These newly established malignant glioma cell lines can be used for further analysis of the mechanisms of tumor growth and progression. 相似文献