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11.
Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014.  相似文献   
12.
儿童舒缓治疗是对患有危及生命疾病的儿童提供身体、心理和精神等全方面的照顾,同时给予家庭支持,旨在为儿童及其家庭提供最佳的生活质量。我国儿童人口基数庞大,不断增加的舒缓治疗服务需求与相关服务资源的发展不足是我国儿童舒缓治疗领域面临的两大现实问题。该文就儿童舒缓治疗的实施和发展现状等进行了综述,为国内开展儿童舒缓治疗相关工作及研究提供参考。  相似文献   
13.
Trigeminal neuralgia is a debilitating condition, and the pain easily spreads to other parts of the face. Here, we established a mouse model of partial transection of the infraorbital nerve (pT-ION) and found that the Connexin 36 (Cx36) inhibitor mefloquine caused greater alleviation of pT-ION-induced cold allodynia compared to the reduction of mechanical allodynia. Mefloquine reversed the pT-ION-induced upregulation of Cx36, glutamate receptor ionotropic kainate 2 (GluK2), transient receptor potential ankyrin 1 (TRPA1), and phosphorylated extracellular signal regulated kinase (p-ERK) in the trigeminal ganglion. Cold allodynia but not mechanical allodynia induced by pT-ION or by virus-mediated overexpression of Cx36 in the trigeminal ganglion was reversed by the GluK2 antagonist NS102, and knocking down Cx36 expression in Nav1.8-expressing nociceptors by injecting virus into the orofacial skin area of Nav1.8-Cre mice attenuated cold allodynia but not mechanical allodynia. In conclusion, we show that Cx36 contributes greatly to the development of orofacial pain hypersensitivity through GluK2, TRPA1, and p-ERK signaling.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00594-4) contains supplementary material, which is available to authorized users.  相似文献   
14.
This study investigated the hypocholesterolaemic effects of bitter melon aqueous extracts (BMAE) in vitro, the inhibitory effects of BMAE on pancreatic cholesterol esterase (CEase) and incorporation of cholesterol into micelles were investigated. BMAE decreased the in vitro micellar solubility of cholesterol in a dose-dependent manner. The conformation of CEase was investigated by means of circular dichroism (CD) and fluorescence. The result revealed the decrease of α-helix contents, increase of β-sheet and exposure of aromatic amino acid residuals. The incorporation of cholesterol into micelles was inhibited by BMAE. A complex was observed by transmission electron microscopy (TEM), which indicated interaction between cholesterol and BMAE. The result revealed that BMAE can play a role in decreased intestinal cholesterol absorption via inhibition of CEase, and of micelle formation.  相似文献   
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16.
目的 分析社区"5+1"糖尿病分阶段达标管理对2型糖尿病患者生存质量的干预效果及其影响因素,为提高患者生存质量提供依据。方法 采用分层整群抽样的方法在山西省、江苏省和宁夏回族自治区选择12个社区卫生服务中心,分别作为干预组(管理方式:社区"5+1"糖尿病分阶段达标管理)、对照组[管理方式:依据《国家基本公共卫生服务规范(2011年版)》的相关要求],进行为期2年的随访观察。采用面对面问卷调查的方式,收集患者的人口学信息等基本信息;采用健康调查简表(SF-36)对患者在干预前后测量生存质量。采用SAS 9.4软件进行双重差分法以及多重线性回归模型分析。结果 基线时共纳入2 467名研究对象,终末时共1 924人接受了为期2年完整的随访管理。干预后,干预组、对照组患者生理健康维度(PCS)、心理健康维度(MCS)评分变化净差值分别为13.6分、29.8分。多重线性回归分析结果显示,影响患者PCS得分的主要因素有年龄、医保类型、基线PCS得分以及所在地区,影响患者MCS得分的主要因素有年龄、医保类型、基线MCS得分、是否合并高血压以及所在地区。结论 社区"5+1"糖尿病分阶段达标管理对2型糖尿病患者生存质量的干预效果较好。  相似文献   
17.
目的 探讨小儿弯刀综合征的诊断、外科治疗方法及治疗后的近、中期结果。方法 回顾性分析2010年1月到2017年12月手术治疗的14例弯刀综合征的临床资料。其中,男7例,女7例;年龄(18.23±28.55)个月,范围在23 d至9岁。合并其他心血管畸形10例,中位心8例,右肺发育不良7例,有侧支循环8例,合并肺动脉高压10例。用SPSS 16.0软件的寿命表(Life Table)做出本组患儿术后生存曲线,评估其近、中期生存状况。结果 9例异常肺静脉(scimitar vein,SV)从下腔静脉切下,端-侧吻合于左心房;SV分成2支2例,1例采用2支SV连同部分下腔静脉壁切下,另1例2支SV从下腔静脉从根部切下侧-侧吻合形成单根SV,均吻合于左心房;SV离左心房距离过大3例,2例将SV吻合在右心房右侧壁,再重建心房间隔,1例SV与自体心包卷管道连接再吻合于左心房。其他心血管畸形同期手术矫治。8例有侧支循环,3例心导管检查时被封堵,5例手术时切断缝合。本组14例手术死亡2例(14.29%),另有1例于术后1年2个月因肺炎、呼吸衰竭死亡。本组术后1、3、5年累积生存率分别为86%、73%和73%。术后出院时有1例移植的SV开口狭窄,血流速度为1.9 m/s;有3例随访期间发现移植SV狭窄,血流速度超过1.6 m/s。结论 弯刀综合征可合并其他心血管畸形、中位心、右肺发育不良等。一般将SV与左心房吻合;SV离左心房距离大或多条SV时,可采用个性化办法将SV吻合于左心房。侧支循环心导管检查时可封堵,或术中切断缝合。  相似文献   
18.
Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders, including Huntington disease [caused by expanded CAG repeats (CAGr) in the HTT gene], and amyotrophic lateral sclerosis [ALS, possibly caused by expanded GGGGCC repeats (G4C2r) in the C9ORF72 gene], of which the molecular mechanisms remain unclear. Here, we demonstrated that lowering the Drosophila homologue of tau protein (dtau) significantly rescued in vivo neurodegeneration, motor performance impairments, and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r. Expression of human tau (htau4R) restored the disease-related phenotypes that had been mitigated by the loss of dtau, suggesting an evolutionarily-conserved role of tau in neurodegeneration. We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome–lysosome fusion, possibly due to lowering the level of BAG3, a regulator of autophagy and tau. Taken together, our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism. Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00518-2) contains supplementary material, which is available to authorized users.  相似文献   
19.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
20.
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