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1.
Ochratoxin A (OTA) is a mycotoxin that mainly causes nephrotoxicity. The single nephrotoxicity of OTA exposure on glomeruli or renal tubule had been well documented, however, the comparison toxicity between it is still unclear. Here, C57BL/6 mice and two types of nephrocyte were treated with concentration-gradient OTA to explore its differentiation nephrotoxicity. Results showed that OTA induced nephrotoxicity in vivo and in vitro, manifested as the deteriorative kidney function in mice and the cut-down cell viability in nephrocyte. Besides, results of murine kidney pathological section and IC50 of two types nephrocyte indicated that OTA-induced toxicity in renal tubule was higher than its in glomeruli. In addition, OTA exposure induced autophagy signaling differentiation expression. It revealed that autophagy was implicated in OTA-induced differential nephrotoxicity in glomeruli and renal tubule. Altogether, we proved that OTA induces a differentiation nephrotoxicity in glomeruli and renal tubule, and it is related to autophagy differential regulation. 相似文献
2.
目的探讨C型凝集素受体Dectin-2在烟曲霉菌感染中的作用及机制。方法用紫外线灭活的烟曲霉菌膨胀态分生孢子刺激野生型(wild type, WT)和Dectin-2缺失(Clec4n-/-)小鼠骨髓来源的巨噬细胞(bone marrow derived macrophages, BMDMs)。刺激20min及40min后,利用Western印迹法检测BMDMs中脾酪氨酸激酶(spleen tyrosine kinase, Syk)和核转录因子κB抑制因子(inhibitor-κB, IκBα)的磷酸化水平。刺激16h后,利用酶联免疫吸附法(enzyme-linked immunosorbent assay, ELISA)检测BMDMs细胞上清液中IL-6、TNF-α和IL-12p40的水平。另一方面,利用压舌感染的方法在WT和Clec4n-/-小鼠中构建烟曲霉菌肺部感染模型。感染2d后,统计小鼠整个肺脏荷菌量,并检测肺脏匀浆液中IL-6和IL-12p40水平。结果体外试验提示,烟曲霉菌刺激后,Dectin-2缺失的BMDMs中Syk和IκBα的磷酸化水平及IL-6、TNF-α和IL-12p40水平显著下降(P<0.05)。体内试验发现,烟曲霉菌感染后,Dectin-2缺失小鼠中肺脏荷菌量显著升高(P<0.05),肺脏匀浆液内IL-6、IL-12p40水平显著降低(P<0.05)。结论C型凝集素受体Dectin-2激活烟曲霉菌诱导的NF-κB信号通路并介导促炎细胞因子的产生,可在小鼠肺烟曲霉菌病动物模型中发挥保护性作用。 相似文献
3.
Bleomycin is a well-recognized antineoplastic drug. However, pulmonary fibrosis (PF) is considered to be the principal drawback that greatly limits its use. Here, we sought to investigate ability of the neurokinin receptor 1 blocker, aprepitant, to prevent PF caused by bleomycin. Male adult Wistar rat groups were given a single intratracheal injection of bleomycin, either alone or in combination with aprepitant therapy for 3 or 14 days. Collagen deposition and a rise in transforming growth factor beta (TGF-β) immunoreactivity in lung tissue serve as evidence of bleomycin-induced PF. The serum levels of lactate dehydrogenase, alkaline phosphatase, and total antioxidant improved after aprepitant therapy.Additionally, it reduced the protein expressions of interferon alpha, tumor necrosis factor alpha, and lung lipid peroxidation. Moreover, aprepitant treatment led to an increase in the antioxidant indices glutathione, glutathione peroxidase, and catalase. Aprepitant is postulated to protect against bleomycin-induced PF by decreasing TGF-β, phosphorylating Smad3, and increasing interleukin 37, an anti-fibrotic cytokine, and G Protein-coupled Receptor Kinase 2. Aprepitant for 14 days considerably exceeded aprepitant for 3 days in terms of improving lung damage and having an anti-fibrotic impact. In conclusion, aprepitant treatment for 14 days may be used as an adjuvant to bleomycin therapy to prevent PF, mostly through inhibiting the TGF-/p-Smad3 fibrotic pathway. 相似文献
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5.
《Health & place》2019
Medical accessibility is an important indicator for evaluating the effectiveness of public health services. However, the previous medical accessibility studies mainly focus on spatial accessibility without considering temporal variation in population distribution which is significant for evaluating access to emergency medical service (EMS). This paper proposes a model of spatio-temporal accessibility to EMS called ST-E2SFCA based on adapting the enhanced two-step floating catchment area (E2SFCA) method. We apply our method to the greater Tokyo area for a large volume of GPS dataset with millions of users and compare the accessibility difference over space and time. To evaluate our model, we also analyze the distinction of our model over different weight sets and compare the performance of ST-E2SFCA with the traditional E2SFCA. The result shows that our method can illustrate the temporal difference and is suitable for measuring the spatio-temporal accessibility to EMS, thus can guide the hospital location selection and urban planning. 相似文献
6.
BackgroundAngiocentric glioma (AG) is a rare, low-grade glioma with slow growth. In 2007, AG was first classified as a solid tumor according to the WHO classification of the central nervous system (WHO class I). The outcome and prognosis of most of the cases are very good, but a few cases with tumor metastasis and disease progression, even death, have been reported. We report a case and systematically analyze previous literature to increase our understanding of the disease and determine the factors that may affect disease progression to make prognostic judgments.Case presentationA young male patient complained of a 3-year history of epilepsy. Anti-epileptic drug treatment was ineffective. An imaging examination revealed a lesion in the left parietal cortex area. Thus, the lesion was completely resected. The pathological diagnosis was angiocentric glioma. During a follow-up of two years, the patient had epilepsy relief controlled by sodium valproate and a disease-free period.ConclusionAG is an epilepsy-related low-grade glioma that heals after complete resection in most reported cases. However, few reported cases have had disease progression and death. This result may be due to the pathological complexity of the diseased tissue. In addition, AG is usually found to have an MYB–QKI rearrangement on genetic analysis. Due to the small number of reported cases and studies, our understanding and knowledge of this disease are still lacking. The potential malignant changes and prognostic factors need to be verified in more than clinical cases and basic research in the future. 相似文献
7.
医学生人格特质与共情能力的相关性研究 《医学教育管理》2021,7(2):169-173
目的 测评医学生的共情能力现状,探讨人格特质对其共情能力的影响,为培养医学生的共情能力提供对策。方法 以上海市3所高校临床医学专业学生为研究对象,采用班级整群抽样的方式进行问卷调研。采用杰斐逊共情量表-医学生版(JSPE-S)和大五人格量表(NEO-FFI)分别评估医学生的共情和人格特质。结果 共发放问卷2 020份,回收有效问卷1 958份,有效率为96.93%。医学生的共情能力总分均值为(103.24±14.35)。共情能力总分与大五人格中的“外向性”“开放性”“宜人性”“严谨性”维度呈显著正相关(r=0.154~0.406, P<0.01),与大五人格中的“神经质”维度呈显著负相关(r=-0.175, P<0.01)。分层回归结果表明:“共情重要性”和“大五人格”量表的5个维度进入回归方程。其中,人格因素占可解释方差变异量的16.2%(P<0.01)。结论 我国医学生的共情能力低于国外医学生,重视人格特质的塑造有助于提高其共情能力。 相似文献
8.
趋化因子CCL8是趋化因子CC家族中的一员,可以在炎症反应和肿瘤免疫等方面发挥重要作用。近来许多研究数据表明,CCL8与人类肿瘤的发生发展密切相关,它在肿瘤微环境中扮演了不可或缺的角色,一方面CCL8可以促进肿瘤细胞的浸润转移,另一方面又可以抑制肿瘤的发生发展。本文主要阐述了目前研究发现的CCL8在肿瘤中的作用,包括肿瘤的发生发展、浸润转移等,以上研究不仅可以帮助我们更加深入的了解肿瘤形成的机制,而且对于寻找更加有效的肿瘤新疗法有着重要的意义。 相似文献
9.
朱晓东 《中国小儿急救医学》2020,(4):268-271
电阻抗断层成像技术(electrical impedance tomography,EIT)作为一项新兴的功能性成像技术,具有无损伤、便携、图像监护等突出特点。肺功能成像是目前EIT最主要的应用领域,可以实现实时动态监测肺通气及血流灌注。本文对肺EIT在儿童呼吸系统疾病及其诊疗过程中的应用基础及临床研究进展进行总结,为未来EIT技术在儿科临床急救领域的推广应用提供帮助。 相似文献
10.
目的验证头脉冲试验(HIMP)和头脉冲抑制试验(SHIMP)在前庭眼动反射中的互补效应。方法选择前庭上神经炎患者33例,健康成人10例(20耳),对前庭上神经炎患者患侧和健康成人左右侧HIMP和SHIMP增益、扫视潜伏期、扫视波振幅及显性扫视产生百分比进行匹配分析,比较HIMP和SHIMP各项参数之间相互关系。结果HIMP增益与SHIMP增益呈线性正相关,并且HIMP增益大于SHIMP增益,差异具有统计学意义(t=5.890,r=0.956,P均=0.000)。HIMP潜伏期大于SHIMP潜伏期,差异具有统计学意义(t=-3.360,P=0.001),但无相关性(r=0.180,P=0.196)。HIMP扫视振幅与SHIMP扫视振幅呈负相关(r=-0.484,P=0.000),HIMP扫视百分比与SHIMP显性扫视百分比呈负相关(r=-0.604,P=0.000)。HIMP增益与HIMP扫视潜伏期、振幅及百分比均呈负相关,且均具有统计学意义(P<0.05)。SHIMP增益与SHIMP代偿性扫视振幅及百分比呈正相关,具有统计学意义(P<0.05)。SHIMP增益与SHIMP扫视潜伏期无相关性(r=-0.044,P=0.756)。结论SHIMP和HIMP均可检查水平性角前庭眼动反射(VOR)的直接通路,代偿性扫视和反代偿性扫视的增益、振幅和扫视产生的百分比可作为动态观察指标评估前庭功能。两者参数变化对评估VOR通路的损伤和恢复情况起到一定指导意义。 相似文献