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41.
4‐(4‐Hydroxyphenyl)‐2‐butanol (rhododendrol)‐induced melanocyte cytotoxicity is enhanced by UVB exposure through generation of oxidative stress 下载免费PDF全文
Noriko Goto Mariko Tsujimoto Hiroshi Nagai Taro Masaki Shosuke Ito Kazumasa Wakamatsu Chikako Nishigori 《Experimental dermatology》2018,27(7):754-762
4‐(4‐Hydroxyphenyl)‐2‐butanol (rhododendrol, RD), a skin‐whitening agent, was reported to cause skin depigmentation in some users, which is attributed to its cytotoxicity to melanocyte. It was reported that cytotoxicity to melanocyte is possibly mediated by oxidative stress in a tyrosinase activity‐dependent manner. We examined the effect of UV radiation (UVR) on RD‐induced melanocyte cytotoxicity as an additional aggravating factor. UVR enhanced RD‐induced cytotoxicity in normal human epidermal melanocytes (NHEMs) via the induction of endoplasmic reticulum (ER) stress. Increased generation of intracellular reactive oxygen species (ROS) was detected. Pretreatment with N‐acetyl cysteine (NAC), antioxidant and precursor of glutathione significantly attenuated ER stress‐induced cytotoxicity in NHEMs treated with RD and UVR. Increase in cysteinyl‐RD‐catechol and RD‐pheomelanin in NHEMs treated with RD and UVR suggested that, after UVR excitation, RD or RD metabolites are potent ROS‐generating substances and that the tendency to produce RD‐pheomelanin during melanogenesis amplifies ROS generation in melanocytes. Our results help to elucidate the development mechanisms of RD‐induced leukoderma and provide information for innovation of safe skin‐whitening compounds. 相似文献
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Cutting efficiency of diamond burs operated with electric high‐speed dental handpiece on zirconia 下载免费PDF全文
Keisuke Nakamura Yusuke Katsuda Shuhei Ankyu Akio Harada Taichi Tenkumo Taro Kanno Yoshimi Niwano Hiroshi Egusa Percy Milleding Ulf Örtengren 《European journal of oral sciences》2015,123(5):375-380
Zirconia‐based dental restorations are becoming used more commonly. However, limited attention has been given to the difficulties experienced, concerning cutting, in removing the restorations when needed. The aim of the present study was to compare the cutting efficiency of diamond burs, operated using an electric high‐speed dental handpiece, on zirconia (Zir) with those on lithium disilicate glass–ceramic (LD) and leucite glass–ceramic (L). In addition, evaluation of the cutting efficiency of diamond burs on Zir of different thicknesses was performed. Specimens of Zir were prepared with thicknesses of 0.5, 1.0, 2.0, and 4.0 mm, and specimens of LD and L were prepared with a thickness of 1.0 mm. Cutting tests were performed using diamond burs with super coarse (SC) and coarse (C) grains. The handpiece was operated at 150,000 rpm with a cutting force of 0.9 N. The results demonstrated that cutting of Zir took about 1.5‐ and 7‐fold longer than cutting of LD and L, respectively. The SC grains showed significantly higher cutting efficiency on Zir than the C grains. However, when the thickness of Zir increased, the cutting depth was significantly decreased. As it is suggested that cutting of zirconia is time consuming, this should be taken into consideration in advance when working with zirconia restorations. 相似文献
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Teiichi Yamane Taro Date Yasuko Kanzaki Keiichi Inada Seiichiro Matsuo Kenri Shibayama Satoru Miyanaga Hidekazu Miyazaki Ken-ichi Sugimoto Seibu Mochizuki 《Circulation journal》2007,71(5):753-760
BACKGROUND: The limited efficacy and complications of segmental ostial pulmonary vein isolation (PVI) for treating atrial fibrillation (AF) have been discussed so, in the present study the feasibility and efficiency of performing segmental pulmonary vein (PV) antrum isolation to treat AF were assessed. METHODS AND RESULTS: A total of 187 patients with drug-refractory AF (paroxysmal 120, persistent 67) underwent segmental PVI guided by circumferential 20-electrode catheters (Lasso). Radiofrequency (RF) current was delivered either at the ostium using a regular Lasso (15-20 mm in diameter, 70 patients: Group 1) or at the antrum using a larger Lasso (25-30 mm in diameter, 117 patients: Group 2). A significantly wider region had to be ablated, with a longer RF application time, to isolate all 4 PVs in Group 2 patients than in Group 1 patients. Although the rate of recurrence of AF after the initial session was equal in both groups, a significantly greater number of patients were free from AF after a mean of 1.4 procedures in Group 2 than in Group 1 (93% vs 76% for paroxysmal AF, 78% vs 48% for persistent AF). CONCLUSIONS: Segmental antral PVI using large-sized Lasso catheters was found to be more effective and safer than ostial PVI for the treatment of AF. 相似文献
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Yoichi Otaki Takashi Ashikaga Taro Sasaoka Ken Kurihara Shunji Yoshikawa Mitsuaki Isobe 《Cardiovascular Revascularization Medicine》2019,20(2):120-125
Background
Long-term clinical outcomes of permanent polymer everolimus-eluting stent (PP-EES) implantation after rotational atherectomy (RA) have not been fully evaluated. We sought to investigate the long-term clinical outcomes of PP-EES implantation after RA and assess the impact of hemodialysis on this treatment strategy.Methods
Patients who underwent percutaneous coronary intervention (PCI) with PP-EES at 22 institutions between January 2010 and December 2011 were enrolled in this multicenter, observational trial. From a total of 1918 registered patients, 113 patients with 115 de-novo lesions who underwent PCI with PP-EES following RA were retrospectively analyzed. The primary endpoint was a major adverse cardiac event (MACE) defined as the composite of cardiac death, non-fatal myocardial infarction (MI), and clinically driven target lesion revascularization (TLR).Results
Long-term follow-up was available for 112 patients (99.1%). The median follow-up period was 2.9 (interquartile range 1.9–3.6) years. The mean age of the patients was 72.3?±?8.8?years and 64 patients (56.6%) had chronic kidney disease (≥stage 3, 42 on hemodialysis). The cumulative incidences of MACE, non-fatal MI, and TLR were 22.1%, 5.3%, and 10.6%, respectively. Cox's proportional hazards analysis showed that the independent predictors of TLR were hemodialysis and chronic total occlusion. (HR, 14.1; 95% CI, 1.74–155.5; p?=?0.01, HR, 9.01; 95% CI, 1.34–62.5; p?=?0.02).Conclusions
PP-EES implantation after lesion modification by RA is considered to be a feasible treatment strategy for heavily calcified lesions. Hemodialysis and chronic total occlusion appeared to be associated with TLR. 相似文献48.
Yamada T Murakami Y Muto M Okada T Okamoto M Toyama J Yoshida Y Tsuboi N Ito T Kondo T Inden Y Hirai M Murohara T 《Journal of cardiovascular electrophysiology》2004,15(7):745-751
INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs. 相似文献
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Naro Ohashi Hiroyuki Takase Taro Aoki Takashi Matsuyama Sayaka Ishigaki Shinsuke Isobe Tomoyuki Fujikura Akihiko Kato Hideo Yasuda 《Medicine》2021,100(19)
Excessive salt intake causes hypertension and cardiovascular diseases (CVDs). B-type natriuretic peptide (BNP) is synthesized and released from the ventricle, and is a surrogate marker reflecting various CVDs. Moreover, when a slight BNP elevation is shown, it leads to a poor prognosis in the general population. However, the relationship between salt intake and BNP levels in the general population remains unclear, especially in those without hypertension and heart diseases.In this study, we recruited 1404 participants without hypertension and electrocardiogram abnormalities, who received regular annual health check-ups in Japan. Plasma BNP levels were measured, and daily salt intake levels were evaluated using urinary samples. In addition, some clinical parameters were obtained, and the data were cross-sectionally analyzed.The median of plasma BNP levels was 10.50 pg/mL, and daily salt intake was 8.50 ± 1.85 g. When dividing participants into quartiles according to daily salt intake, those with the highest daily salt intake revealed the highest plasma BNP levels. Plasma BNP levels were significantly and positively associated with daily salt intake. Moreover, multiple linear regression analyses revealed that plasma BNP levels showed a significant positive association with daily salt intake levels after adjustments.Plasma BNP levels were significantly and positively associated with daily salt intake after adjustment in the general population. Plasma BNP levels may be a surrogate marker reflecting salt-induced heart diseases. 相似文献