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1.
Xiaoyan Lu Isabelle R. Miousse Sandra V. Pirela Jodene K. Moore Stepan Melnyk 《Nanotoxicology》2016,10(5):629-639
Evidence continues to grow on potential environmental health hazards associated with engineered nanomaterials (ENMs). While the geno- and cytotoxic effects of ENMs have been investigated, their potential to target the epigenome remains largely unknown. The aim of this study is two-fold: 1) determining whether or not industry relevant ENMs can affect the epigenome in vivo and 2) validating a recently developed in vitro epigenetic screening platform for inhaled ENMs. Laser printer-emitted engineered nanoparticles (PEPs) released from nano-enabled toners during consumer use and copper oxide (CuO) were chosen since these particles induced significant epigenetic changes in a recent in vitro companion study. In this study, the epigenetic alterations in lung tissue, alveolar macrophages and peripheral blood from intratracheally instilled mice were evaluated. The methylation of global DNA and transposable elements (TEs), the expression of the DNA methylation machinery and TEs, in addition to general toxicological effects in the lung were assessed. CuO exhibited higher cell-damaging potential to the lung, while PEPs showed a greater ability to target the epigenome. Alterations in the methylation status of global DNA and TEs, and expression of TEs and DNA machinery in mouse lung were observed after exposure to CuO and PEPs. Additionally, epigenetic changes were detected in the peripheral blood after PEPs exposure. Altogether, CuO and PEPs can induce epigenetic alterations in a mouse experimental model, which in turn confirms that the recently developed in vitro epigenetic platform using macrophage and epithelial cell lines can be successfully utilized in the epigenetic screening of ENMs. 相似文献
2.
中风病是临床的常见病、多发病。本病病因较多,病情变化迅速,证型繁杂,不同的文献中证候分类差异较大。证候分类的繁杂给临床工作者治疗中风病带来极大不便。本文对以证候要素(内风、内火、痰湿、瘀血、气虚、阴虚)为切入点论治中风病的理论进行探讨,并举例论证其临床疗效。 相似文献
3.
目的 探讨糖尿病前期的中医证型及证素分布特点。方法 检索中国知网、万方及维普三大数据库中收录的自建库以来有关糖尿病前期证型的临床研究文献,对中医证型进行规范整理,建立数据库,提取证素,运用数据挖掘技术中的关联分析、聚类分析探究证素分布规律。结果 共纳入10篇文献,总有效病例1620例,证型经规范处理后整理为18个,主要证型为脾虚痰湿证。共提取证素13个,主要病位证素为脾,主要病性证素为气虚、湿和痰,关联分析显示脾—湿支持度和置信度最高,聚类分析结果可得到3个聚类组。结论 糖尿病前期病位在脾,气虚、脾、痰、湿是常见证素,临床诊治糖尿病前期应注重从脾论治,需辨证施治。 相似文献
4.
Oliver Sartor MD Daniel Heinrich MD Neil Mariados MD Maria José Méndez Vidal MD Daniel Keizman MD Camilla Thellenberg Karlsson MD Avivit Peer MD Giuseppe Procopio MD Stephen J. Frank MD Kalevi Pulkkanen MD Eli Rosenbaum MD Stefano Severi MD José Trigo MD Lucia Trandafir MD Volker Wagner MD Rui Li MS Luke T. Nordquist MD 《The Prostate》2019,79(14):1683-1691
5.
作者对30名90岁以上老人作纯音测听、高频测听和发中微量元素检测,与<60岁组人进行比较。结果:老年组纯音全频率听阈与对照组相比差异非常显著(P<0.01),高频测听,90岁组随着频率提高,听到耳数越来越少。并观察到90岁组发中锌、镁微量元素均低于<60岁组,两组间有显著差异(P<0.01)。对90岁组老人听力的特点,发中锌、镁微量元素含量减少对老年性耳聋的影响进行探讨。 相似文献
6.
Paroxysmal dyskinesias (PxDs) are involuntary, episodic movements that include paroxysmal kinesigenic (PKD), paroxysmal nonkinesigenic (PNKD), and paroxysmal hypnogenic (PHD) varieties. Although most PxDs are primary (idiopathic or genetic), we found 17 of our 76 patients with PxD (22%) to have an identifiable cause for their PxD (10 men; mean age, 41.4 years). Causes included peripheral trauma (in three patients), vascular lesions (in four), central trauma (in four), kernicterus (in two), multiple sclerosis (in one), cytomegalovirus encephalitis (in one), meningovascular syphilis (in one), and migraine (in one). The latency from insult to symptom onset ranged from days (trauma) to 18 years (kernicterus), with a mean of 3 years. Nine patients had PNKD, two had PKD, five had mixed PKD/PNKD, and one had PHD. Hemidystonia was the most common expression of the paroxysmal movement disorder, present in 11 patients. Both of the patients with PKD had symptom durations of <5 minutes. Symptom duration ranged from 10 seconds to 15 days for PNKD and from 5 minutes to 45 minutes for mixed PKD/PNKD. There were no uniformly effective therapies, but anticonvulsant drugs, clonazepam, and botulinum toxin injections were the most beneficial. Awareness of the variable phenomenology and the spectrum of causes associated with secondary PxD will allow for more timely diagnosis and early intervention. 相似文献
7.
选择性子宫动脉栓塞治疗症状性子宫肌瘤 总被引:1,自引:0,他引:1
目的:评价选择性子宫动脉栓塞 (U AE)治疗症状性子宫肌瘤 (SUF)的临床疗效。方法:12例 SUF患者行双侧子宫肌瘤供血动脉的栓塞治疗 ,栓塞剂为聚乙烯醇微球颗粒 (PVA)。结果:栓塞成功率 10 0 % ,无严重并发症发生。随访 3~ 2 4个月 ,B超示术后 6个月肌瘤平均缩小 4 5 % ,1例肌瘤消失 ,均伴有月经量的明显减少。 结论 :U AE是治疗 SU F的安全方法 ,近期疗效肯定。 相似文献
8.
W. Ptzl P. Kümpers T. Szuwart T. Filler B. Marquardt J. Steinbeck 《Journal of orthopaedic research》2004,22(6):1345-1350
Despite widespread use of radiofrequency (RF)-shrinkage, there have been no studies on the influence of RF-energy on neural elements of collagenous tissue. The purpose of this study was to examine the effect of RF-shrinkage on neural structures of capsuloligamentous tissue and the recovery of neural elements under different postoperative treatment protocols. One patellar tendon of 46 New-Zealand-White rabbits was shrunk. Six rabbits were sacrificed immediately postoperative. Twenty rabbits were not immobilized, 10 were immobilized for 3 and 10 were immobilized for 6 weeks. A monoclonal antibody, specific against a neurofilament protein, was used to detect nerves and neural structures. Staining pattern of nerve fibres was significantly altered immediately postoperative. After 3 weeks the number of nerve fibres and bundles decreased significantly in immobilized and non-immobilized limbs. The loss of nerve fibres was significantly less in immobilized limbs. At 6 weeks the number of neural elements in immobilized limbs increased to the level of untreated control tissue. In non-immobilized limbs we found no recovery of neural elements 9 weeks postoperatively. At this time the number of nerve fibres and bundles was still significantly less compared to the untreated control limbs. RF-shrinkage causes significant alteration of neural elements. Under immobilization nerve fibres and bundles reach the level of normal untreated tissue. Careful rehabilitation is important after RF-shrinkage. Not only for biomechanical reasons, but also to allow the neural elements to recover, thermally modified tissue should be protected from normal physiologic loads. 相似文献
9.
10.
本文于1993年4月调查了新疆拜城县重病区查尔齐农场中与中病区赛里木乡的饮水,土壤,粮食,学龄儿童头发中Zn,Cu,Mn,Ca,Li,Se6种元素无机元素的含量。结果表明,重病区小麦中Ca的含量显著高于中病区(P〈0.05),重病区饮水及小麦中Mn的含量显著低于中病区(P〈0.05)。这些结果揭示重病区查尔齐与中病区赛里木乡的病情相比较,除缺碘较为严重这一主要原因之外,高Ca,低Mn也可能与查尔齐 相似文献