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71.
Yi‐Hui Lee Show‐Mei Chuang Sheng‐Chi Huang Xiaotong Tan Ruei‐Yue Liang Gordon C. C. Yang Pin Ju Chueh 《Environmental toxicology》2017,32(4):1170-1182
In view of the extensive use of nanoparticles in countless applications, a fast and effective method for assessing their potential adverse effects on the environment and human health is extremely important. At present, in vitro cell‐based assays are the standard approach for screening chemicals for cytotoxicity because of their relative simplicity, sensitivity, and cost‐effectiveness compared with animal studies. Regrettably, such cell‐based viability assays encounter limitations when applied to determining the biological toxicity of nanomaterials, which often interact with assay components and produce unreliable outcomes. We have established a cell‐impedance‐based, label‐free, real‐time cell‐monitoring platform suitable for use in a variety of mammalian cell lines that displays results as cell index values. In addition to this real‐time screening platform, other traditional cytotoxicity assays were employed to validate cytotoxicity assessments. We suggest that the cell impedance measurement approach is effective and better suited to determining the cytotoxicity of nanomaterials for environmental safety screening. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1170–1182, 2017. 相似文献
72.
目的:探讨化红胶囊对去势大鼠骨质疏松的影响及作用机制。方法:取3月龄SD雌性大鼠经去势手术或者是假阳性手术后,喂以去大豆特殊饲料7周以诱导骨丢失。经去势手术大鼠进一步分为化红胶囊组(1.0,0.5,0.25 g.kg-1)、模型组、己烯雌酚组,连续给药12周。检测大鼠血清的骨钙素、雌二醇、尿中脱氧吡啶啉含量,以及椎骨末端骨小梁的变化情况。结果:化红胶囊能降低大鼠血清中骨钙素以及尿液中脱氧吡啶啉含量,提高血清中雌二醇含量,与模型组相比,1.0g.kg-1,0.5 g.kg-1剂量组差异有显著性(P<0.05或P<0.01)。骨小梁的形态学观察及数据分析显示,与模型组相比,化红胶囊可以提高骨小梁面积百分比,与模型组相比,1.0,0.5 g.kg-1剂量组差异有显著性(P<0.05或P<0.01)。结论:化红胶囊可以降低去势大鼠骨转换率和骨吸收程度,提高骨小梁平均面积百分比,是一种潜在的治疗绝经后骨质疏松药物,其作用机制之一可能与化红胶囊雌激素样作用有关。 相似文献
73.
Ming‐Wei Chao Yu‐Hsiu Yang Yu‐Chen Chuang Meng‐Chi Chung Chia‐Yi Tseng 《Environmental toxicology》2017,32(4):1412-1425
PM2.5 travels along the respiratory tract and enters systemic blood circulation. Studies have shown that PM2.5 increases the incidence of various diseases not only in adults but also in newborn infants. It causes chronic inflammation in pregnant women and retards fetal development. In this study, pregnant rats were exposed to PM2.5 for extended periods of time and it was found that PM2.5 exposure increased immune cells in mother rats. In addition, cytokines and free radicals rapidly accumulated in the amniotic fluid and indirectly affected the fetuses. The authors collected cerebral cortex and hippocampus samples at E18 and analyzed changes of miRNA levels. Expression levels of cortical miR‐6315, miR‐3588, and miR‐466b‐5p were upregulated, and positively correlated with the genes Pkn2 (astrocyte migration), Gorab (neuritogenesis), and Mobp (allergic encephalomyelitis). In contrast, PM2.5 decreased expression of miR‐338‐5p and let‐7e‐5p, both related to mental development. Further, PM2.5 exposure increased miR‐3560 and let‐7b‐5p in the hippocampus, two proteins that regulate genes Oxct1 and Lin28b that control ketogenesis and glycosylation, and neural cell differentiation, respectively. miR‐99b‐5p, miR‐92b‐5p, and miR‐99a‐5p were decreased, leading to reduced expression of Kbtbd8 and Adam11 which reduced cell mitosis, migration, and differentiation, and inhibited learning abilities and motor coordination of the fetus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1412–1425, 2017. 相似文献
74.
目的 探讨愈风宁心片对偏头痛大鼠模型的镇痛作用及机制。方法 SD大鼠随机分成6组:对照组、模型组、苯甲酸利扎曲普坦片(阳性药,0.9 mg·kg-1)组和愈风宁心片低、中、高剂量(378、756、1 512 mg·kg-1)组,每天ig给药1次,连续10 d。末次给药后1 h,除对照组外,其余各组大鼠在头颈处sc 10 mg·kg-1硝酸甘油建立偏头痛大鼠模型,观察疼痛行为学指标,试剂盒法检测血清中疼痛相关因子缩胆囊素(CCK)、白细胞介素-1β (IL-1β)、前列腺素E(2 PGE2)含量;利用小鼠醋酸扭体实验、小鼠右后足跖部福尔马林致痛实验观察愈风宁心片低、中、高剂量(546、1 092、2 184 mg·kg-1)对小鼠扭体反应和舔足时长的影响。结果 偏头痛实验结果表明,与模型组比较,愈风宁心片各剂量组和苯甲酸利扎曲普坦片组的挠头、甩头次数和行为学评分显著降低(P<0.05、0.01);愈风宁心片中、高剂量组血清CCK水平显著降低(P<0.05、0.01),低、中、高剂量组血清PGE2、IL-1β水平显著降低(P<0.05、0.01)。醋酸扭体实验结果表明,与模型组比较,愈风宁心片中、高剂量组小鼠扭体次数显著降低(P<0.05、0.01),高剂量组小鼠扭体反应潜伏期显著延长(P<0.01)。福尔马林致痛实验结果表明,与模型组比较,各给药组均能显著缩短小鼠的舔足时长(P<0.01)。结论 愈风宁心片对偏头痛模型具有镇痛作用,其机制可能与调节中枢及外周神经系统、改善疼痛相关因子含量有关。 相似文献
75.
Blood pressure change during phacoemulsification and femtosecond laser-assisted cataract surgery
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Hung-Yuan Lin Ching-Jen Tung Guo-Xing Xu Chun-Chi Wang Hsin-Yang Chen Ya-Jung Chuang Wen-Fu Li Pi-Jung Lin 《国际眼科》2016,9(11):1614-1618
AIM: To evaluate blood pressure (BP) changes during phacoemulsification (PC) and femtosecond laser (FSL)-assisted cataract surgery.
METHODS: A retrospective chart review was performed for all patients who received traditional phacoemulsification surgery (PC group) and FSL-assisted cataract surgery (FS group) from July 2013 to December 2014. Totally 206 eyes from 133 patients receiving the two types of procedures were included. Patient characteristics (age, gender, and hypertension history), pre- and post-operative BPs were collected. RESULTS: The pro-operative systolic and diastolic BPs (mm Hg) were 124.89±20.48 vs 126.98±16.85, and 71.88±9.81 vs 73.56±10.03, in PC and FS groups, respectively. While the post-operative systolic and diastolic BPs (mm Hg) were 130.13±22.59 vs 134.77±17.52, and 73.41±11.62 vs 78.89±12.2, in PC and FS groups, respectively. Paired-sample t-tests showed obvious systolic and diastolic BP elevations in FS group after surgery (P=0.001 and 0.007) and no reliability in PC group (P=0.094 and 0.359). A linear regression model revealed systolic and diastolic BP elevations, which were related to longer surgical times for FS group (P=0.008 and 0.021). Age, gender, and hypertension history were not correlated with blood pressure elevation in either group.
CONCLUSION: BP increases but at a limited level after FSL-assisted cataract surgery compared to traditional phacoemulsificationKEYWORDS: cataract surgery; blood pressure; femtosecond-assisted cataract surgery; phacoemulsification 相似文献
76.
目的:探索LINC AC004463.6通过PI3K/AKT/BCL-2通路对肝细胞癌(hepatocellular carcinoma,HCC)细胞生物学行为的影响。方法:运用细胞转染技术构建细胞系,实时荧光定量PCR验证,运用CCK8法、Transwell实验、EdU实验和流式细胞仪检测凋亡技术观察细胞功能学变化,运用Western blotting和ELISA技术探索其可能作用机制。结果:LINC AC004463.6在HCC中异常上调,在HCC细胞系和L02细胞中均检测到LINC AC004463.6的水平。选取SMCC7721和QGY7701作为LINC AC004463.6高表达细胞。CCK8和EdU实验结果表明,LINC AC004463.6表达降低显著抑制了SMCC7721和QGY7701细胞的增殖。而LINC AC004463.6基因敲除细胞中过表达LINC AC004463.6可使细胞增殖恢复和增强。Transwell实验检测表明shRNA处理的SMCC7721和QGY7701细胞侵袭性显著降低;经Lv-Rescue质粒处理后,细胞侵袭恢复并增强。LINC AC004463.6表达降低的细胞凋亡水平较高;LINC AC004463.6基因在LINC AC004463.6基因敲低的细胞中过表达后,细胞的凋亡水平有所恢复。Western blotting和ELISA检测提示shRNA组细胞BCL-2蛋白表达水平明显下调,同时PI3K和AKT蛋白表达水平明显下降;与此相反BAX蛋白表达水平升高。结论:LINC AC004463.6可能通过PI3K/AKT/BCL-2通路改变肿瘤细胞的生物学行为。LINC AC004463.6可能是诊断HCC的一个前瞻性生物标志物。 相似文献
77.
目的:探讨体部伽玛刀联合长春瑞滨、顺铂治疗局部晚期非小细胞肺癌的临床疗效及不良反应。方法:自2008年1月-2010年7月,对101例非小细胞肺癌患者按治疗方法分为伽玛刀联合长春瑞滨、顺铂(联合组)52例和单纯应用长春瑞滨、顺铂(对照组)49例,比较两组治疗后的近期疗效、生存期及不良反应。结果:联合组、对照组有效率分别为82.69%和53.06%,两组1年生存率分别为69.23%,42.86%。联合组的急性放射性肺损伤发生率11.54%,急性放射性食管损伤发生率9.62%,均为1—2度。两组的血液毒性主要表现为白细胞下降,另外还合并有恶心、呕吐等,联合组发生几率明显高于对照组,但经过对症治疗均能顺利完成治疗。结论:伽玛刀联合长春瑞滨、顺铂治疗能显著提高局部晚期肺癌患者的近期疗效、生存时间;白细胞下降、恶心、呕吐等不良反应较单纯化疗组也明显增加,有部分患者还会出现急性放射性肺损伤,急性放射性食管损伤,但经过对症处理基本恢复正常不影响治疗。 相似文献
78.
Chuang PH Hsieh PW Yang YL Hua KF Chang FR Shiea J Wu SH Wu YC 《Journal of natural products》2008,71(8):1365-1370
Four new cyclopeptides, cyclomontanins A-D (1- 4), annomuricatin C (5), and (+)-corytuberine were isolated from a methanol extract of Annona montana seeds. Their structures were elucidated by 2D NMR analysis, ESIMS/MS fragment evidence, and chemical means. The structure of 1 was confirmed by synthesis. Compounds 1, 3, and 4 exhibited anti-inflammatory activity in vitro using the J774.1 macrophage model. 相似文献
79.
80.
BACKGROUND: The specimen from a vaginal cuff fistula between the vagina and abdominal cavity revealed endometriosis. Culture of the fluid revealed Streptococcus viridans. CASE: A 44-year-old woman presented with lower abdominal pain for 1 week. She also had cyclic vaginal spotting that had started 1 month after she underwent laparoscopically assisted vaginal hysterectomy for a myoma 2 years earlier. One year prior to this admission, she was noted to have a right endometrioma on a sonographic examination; monthly follow-up revealed that the cyst was enlarging. The patient was admitted for surgery. On laparotomy, severe adhesions were noted. After adhesiolysis, a right adnexal cyst with chocolatelike contents mixed with malodorous, yellowish, mucoid fluid was noted. A vaginal cuff fistula between the vagina and abdominal cavity was also noted. The specimen from this area revealed endometriosis. Culture of the fluid showed Streptococcus viridans. CONCLUSION: Various laparoscopic complications are cited in the literature. Although rare, the risk of infection after laparoscopy can occur. In our case the infection may have been caused by the presence of vaginal cuff fistula in the presence of endometriosis. 相似文献