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101.
Inflammation plays a pivotal role in the pathogenesis of many diseases in the central nervous system. Caudate nucleus (CN), the largest nucleus in the brain, is also implicated in many neurological disorders. 2-Arachidonoylglycerol (2-AG), the most abundant endogenous cannabinoid and the true natural ligand for CB1 receptors, has been shown to exhibit neuroprotective effects through its anti-inflammatory action from proinflammatory stimuli in hippocampus. However, it is still not clear whether 2-AG is also able to protect CN neurons from proinflammation stimuli. In the present study, we discovered that 2-AG significantly protects CN neurons in culture against lipopolysaccharide (LPS)-induced inflammatory response. 2-AG is capable of suppressing elevation of LPS-induced cyclooxygenase-2 expression associated with ERK/p38MAPK/NF-κB signaling pathway in CB1 receptor-dependant manner in primary cultured CN neurons. Moreover, 2-AG inhibits LPS-induced increase in voltage-gated sodium channel currents and hyperpolarizing shift of activation curves through CB1 receptor-dependant pathway. Our study suggests the therapeutic potential of 2-AG for the treatment of some inflammation-induced neurological disorders and pain.  相似文献   
102.
MicroRNAs (miRNAs) are small noncoding RNAs that have been critically implicated in several human cancers. miRNAs are thought to participate in various biological processes, including proliferation, cell cycle, apoptosis, and even the regulation of the stemness properties of cancer stem cells. In this study, we explore the potential role of miR-300 in glioma stem-like cells (GSLCs). We isolated GSLCs from glioma biopsy specimens and identified the stemness properties of the cells through neurosphere formation assays, multilineage differentiation ability analysis, and immunofluorescence analysis of glioma stem cell markers. We found that miR-300 is commonly upregulated in glioma tissues, and the expression of miR-300 was higher in GSLCs. The results of functional experiments demonstrated that miR-300 can enhance the self-renewal of GSLCs and reduce differentiation toward both astrocyte and neural fates. In addition, LZTS2 is a direct target of miR-300. In conclusion, our results demonstrate the critical role of miR-300 in GSLCs and its functions in LZTS2 inhibition and describe a new approach for the molecular regulation of tumor stem cells.  相似文献   
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目的分析我院肾移植患者他克莫司血药浓度的控制情况,探讨他克莫司血药浓度与肝肾功能之间的关系,以期为临床的合理用药提供依据。方法收集我院2011年11月至2013年4月96例肾移植患者他克莫司血药浓度的数据,及血药浓度测定当天的生化检测结果。根据他克莫司血药浓度(A)测定结果,将其分为4组(I组,A≤6 ng/mL;II组,6〈A≤10 ng/mL;III组,10〈A≤15 ng/mL;IV组,A〉15 ng/mL),对4组中的各项生化指标及不良反应比例进行统计分析。结果红细胞(P=0.57),血红蛋白(P=0.60),血小板(P=0.12),总胆红素(P=0.58),谷氨酰基转移酶(P=0.46),天门冬氨酸氨基转移酶(P=0.98)和丙氨酸氨基转移酶(P=0.40)在4组之间没有统计学意义;而白细胞(P=0.007),碱性磷酸酶(P=0.004)和血尿素氮(P=0.007)在4组之间差异有统计学意义。当患者的他克莫司血药浓度维持在6-15 ng/mL 时,其肾小球滤过率估计值(estimated glo-merular filtration rate,eGFR)(70.2 mL/min)要明显高于≤6 ng/mL(58.2 mL/min)和〉15 ng/mL (66.2 mL/min)。同时,感染及中重度贫血的风险也较低,但他克莫司血药浓度与肝功能异常比例之间未发现显著的相关性。结论他克莫司血药浓度维持在6-15 ng/mL有利于患者肾功能的维持,同时能够降低感染和中重度贫血的风险,这一结果将有利于他克莫司的临床使用。  相似文献   
105.
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卢绮萍 《消化外科》2014,(7):511-515
细菌耐药发展迅猛,严重威胁患者的健康和生命,是全球抗感染领域关注的重点问题.在外科领域,高危患者尤应密切关注.消化道屏障功能不全,条件致病菌异常增多;免疫功能低下或障碍,以致条件致病菌毒性和患者易感性相对增强;重症患者(尤其ICU患者)接受多种医疗护理措施,使得耐药菌易感机会增多;医务人员由于知识不足和对病情严重度的顾虑,不合理应用抗生素等均可导致耐药菌感染性增强,需引起高度关注.应通过对相关知识的认真学习,严格按照各项规定科学用药,杜绝抗生素的滥用,保护患者尤其是危重患者的消化道屏障和免疫功能;注重运用精细手术、通畅引流等专科技术,及时检测、发现感染致病菌给予靶向治疗;加强各项医疗护理技术的无菌操作等综合措施的监控,最大限度地防治、控制耐药菌的产生和传播,促进患者康复.  相似文献   
108.
Peritoneal adhesions are fibrous tissues formed after surgery. Both cytokines and transforming growth factors (TGFs) are involved in this process. The objective of this study was to investigate the cross talk between these entities. Peritoneal drainage fluid after surgery from patients and rodent models was examined by enzyme‐linked immunosorbent assay and fluorescence‐activated cell sorter. Data showed that the concentrations of interferon (IFN)‐γ and interleukin (IL)‐17 reached their peaks 6–12 hours after surgery, whereas TGF‐β1 concentrations showed two postoperative peak time points at 2 and 72–96 hours. By neutralizing IFN‐γ, IL‐17 6–12 hours, and TGF‐β1 72–96 hours after surgery, the degree of adhesion reduced significantly. However, neutralizing TGF‐β1 2 hours after surgery did not affect adhesion formation. Furthermore, in vitro studies showed that compared with the fibroblasts that were directly stimulated with TGF‐β1, the prestimulation of IL‐17 promoted plasminogen activator inhibitor‐1 production while inhibiting tissue‐type plasminogen activator production. Moreover, additional stimulation with IFN‐γ enhanced this effect. Together, these data indicate that IL‐17 may promote adhesion formation by increasing the reaction of fibroblasts against TGF‐β1. Blocking IL‐17 might have a therapeutic potential in preventing adhesion formation after surgery.  相似文献   
109.
背景 铁是人体内极其重要的微量元素,参与了许多生物大分子的构成和基本的生命活动.人体内有一套精密完善的储存、转运、调控系统来维持铁稳态,当这一复杂的网络系统出现障碍时将会导致铁代谢紊乱. 目的 综述脑内铁过载在神经退行性疾病发生发展中的重要作用. 内容 通过对近年来相关文献的总结,主要对铁的转运相关蛋白、铁稳态的调节系统、转运机制等方面对铁过载的形成及其与神经退行性疾病的关系进行了初步探讨,脑内异常高浓度的铁参与了阿尔茨海默病、帕金森病等多种神经退行性疾病的病理过程. 趋向 脑内铁过载引起神经退行性变的机制正被逐步阐明,但仍有许多问题有待解决.通过利用铁螫合剂来降低脑内铁过载可能是治疗这类疾病的一个潜在靶点.  相似文献   
110.
Depression is a complex, heterogeneous mental disorder. Currently available antidepressants are only effective in about one-third to one-half of all patients. The mechanisms underlying antidepressant response and treatment resistance are poorly understood. Recent clinical evidence implicates the involvement of leptin in treatment response to antidepressants. In this study, we determined the functional role of the leptin receptor (LepRb) in behavioral responses to the selective serotonergic antidepressant fluoxetine and the noradrenergic antidepressant desipramine. While acute and chronic treatment with fluoxetine or desipramine in wild-type mice elicited antidepressant-like effects in the forced swim test, mice null for LepRb (db/db) displayed resistance to treatment with either fluoxetine or desipramine. Fluoxetine stimulated phosphorylation of Akt(Thr308) and GSK-3β(Ser9) in the hippocampus and prefrontal cortex (PFC) of wild-type mice but not in db/db mice. Desipramine failed to induce measurable changes in Akt, GSK-3β or ERK1/2 phosphorylation in the hippocampus and PFC, as well as hypothalamus of either genotype of mice. Deletion of LepRb specifically from hippocampal and cortical neurons resulted in fluoxetine insensitivity in the forced swim test and tail suspension test while leaving the response to desipramine intact. These results suggest that functional LepRb is critically involved in regulating the antidepressant-like behavioral effects of both fluoxetine and desipramine. The antidepressant effects of fluoxetine but not desipramine are dependent on the presence of functional LepRb in the hippocampus and cortex.  相似文献   
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