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91.
Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor, and it may be neuroprotective against cerebral ischemia injury. However, the precise mechanisms of the effects of apelin-13 remain to be elucidated. To investigate the effects of apelin-13 on apoptosis and autophagy in models of cerebral ischemia/reperfusion injury, a rat model was established by middle cerebral artery occlusion. Apelin-13(50 μg/kg) was injected into the right ventricle as a treatment. In addition, an SH-SY5 Y cell model was established by oxygen-glucose deprivation/reperfusion, with cells first cultured in sugar-free medium with 95% N2 and 5% CO2 for 4 hours and then cultured in a normal environment with sugar-containing medium for 5 hours. This SH-SY5 Y cell model was treated with 10–7 M apelin-13 for 5 hours. Results showed that apelin-13 protected against cerebral ischemia/reperfusion injury. Apelin-13 treatment alleviated neuronal apoptosis by increasing the ratio of Bcl-2/Bax and significantly decreasing cleaved caspase-3 expression. In addition, apelin-13 significantly inhibited excessive autophagy by regulating the expression of LC3 B, p62, and Beclin1. Furthermore, the expression of Bcl-2 and the phosphatidylinositol-3-kinase(PI3 K)/Akt/mammalian target of rapamycin(mTOR) pathway was markedly increased. Both LY294002(20 μM) and rapamycin(500 nM), which are inhibitors of the PI3 K/Akt/mTOR pathway, significantly attenuated the inhibition of autophagy and apoptosis caused by apelin-13. In conclusion, the findings of the present study suggest that Bcl-2 upregulation and mTOR signaling pathway activation lead to the inhibition of apoptosis and excessive autophagy. These effects are involved in apelin-13-induced neuroprotection against cerebral ischemia/reperfusion injury, both in vivo and in vitro. The study was approved by the Animal Ethical and Welfare Committee of Jining Medical University, China(approval No. 2018-JS-001) in February 2018.  相似文献   
92.
青光眼是世界范围内导致不可逆失明的主要疾病,发病率逐年升高,视网膜神经节细胞(RGC)凋亡被认为是青光眼病变的最早形式。补体失调是青光眼早期视神经损害的特征改变,抑制补体系统能够阻止多种危险因素对RGC的损伤,可以在眼内压持续升高的情况下保护视网膜神经元树突和突触的完整性,阻止神经损伤进一步发展,是近年来青光眼视神经保护药物研发的热点。中草药来源的抗补体活性成分开发成本低,并可以直接在体内被利用,而且其对补体的调控是多成分,多途径的,因此,具有良好的应用前景。本文综述了补体系统在青光眼视神经损害中的病理机制和干预效应的研究进展,为进一步研究补体调控在视神经保护中的作用提供参考。  相似文献   
93.
《Neuromodulation》2021,24(7):1258-1268
ObjectivesConstipation and opioid-induced constipation (OIC) are common with limited treatment options. We investigated whether a noninvasive method of auricular vagal nerve stimulation (aVNS) could be used for treating OIC and explored its potential mechanisms and neural pathways in a rodent model of OIC.Materials and MethodsSprague–Dawley were chronically implanted with one pair of auricular electrodes for aVNS. Sixteen rats were treated with loperamide for a week while another 16 rats received bilateral vagotomy, then randomly treated with aVNS or sham-aVNS for a week. In addition, eight normal rats were implanted with a polyethylene catheter in the proximal colon for assessing whole colon transit.Results1) The number of fecal pellets and water content in feces increased after aVNS, compared with sham-aVNS. 2) aVNS accelerated colon transit and whole gut transit, compared with sham-aVNS. 3) In colon tissues, aVNS increased the protein expression of choline acetyltransferase, glial cell line-derived neurotrophic factor and the c-kit expression in myenteric interstitial cells of Cajal but decreased the protein expression of neural nitric oxide synthase (p < 0.05 for all, vs. sham-VNS). 4) The prokinetic effects of aVNS were abolished by both subdiaphragmatic vagotomy and atropine. 5) aVNS increased the c-fos expression in both nucleus tractus solitarius and dorsal motor nucleus of vagus, and increased vagal efferent activity (p < 0.05, vs. sham-VNS).ConclusionsaVNS improves OIC by enhancing colon motility and restoring enteric neural functions mediated via the central and vagal efferent pathway.  相似文献   
94.
Minimally invasive procedures have been increasing in spine surgery, and interest in robotic systems has inclined. In this study, we aimed to evaluate feasibility of a robotic-assisted thoracic spine interbody fusion in a swine model. Neurosurgeons performed the surgical procedures with robotic surgery certificates on the Da Vinci Xi Surgical System. Surgical approaches were applied using four ports while the swine was in the left lateral position. The surgical procedure was accomplished in 70 min including positioning and preparation of robotic system (20 min), placement of ports and thoracic dissection and confirmation of level with the C-arm system (10 min), discectomy and cage insertion (15 min), control of cage position via the C-arm system and closure (10 min). This study showed the anterior thoracic approach with robotic surgery is safe and feasible with providing a wide working area and high image quality.  相似文献   
95.
96.
Sleep apnea is highly associated with atrial fibrillation (AF), and both diseases are highly prevalent in the United States. The mechanistic underpinnings that contribute to their association remain uncertain, but numerous possible mechanisms have been proposed, including dysfunction of the cardiac autonomic nervous system (ANS). Studies have reported that apnea induces hyperactivity of the ANS, leading to increases in AF susceptibility. This review compiles the latest evidence on the role of the ANS in sleep-apnea-induced AF.  相似文献   
97.
Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase(PI3 K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3 K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting(GV24) and Baihui(GV20) acupoints, with a dilatational wave(1–20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3 K/Akt signaling pathwayrelated factors Beclin-1, mammalian target of rapamycin(mTOR), and PI3 K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3 K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting(GV24) and Baihui(GV20) acupoints activated the PI3 K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China(approval No. 8150150901) on March 10, 2016.  相似文献   
98.
阿尔茨海默病(Alzheimer′s disease,AD)是一种常见的神经系统退行性疾病,磷酸化Tau蛋白异常聚集所形成的神经纤维缠结(Neurofibrillary tangles,NFTs)是AD的典型病理特征,直接参与AD的发生发展。因此,AD的治疗可从调节磷酸化Tau蛋白异常聚集入手。中医学认为“痰浊”是导致AD发生的重要病理因素之一,“正气亏虚,痰浊蒙窍”是AD的核心病机。“痰浊”与磷酸化Tau蛋白异常聚集密切相关,磷酸化Tau蛋白异常聚集可归属“痰浊”的范畴。化痰开窍与减少磷酸化Tau蛋白聚集在AD的治疗中有不谋而合之处。泛素-蛋白酶体系统(Ubiquitin-proteasome system,UPS)是细胞内蛋白降解的主要途径,参与AD进程中磷酸化Tau蛋白的降解。UPS功能受损是磷酸化Tau蛋白异常聚集和AD发生的重要原因。本文试图从中医“痰”的视角认识磷酸化Tau蛋白异常聚集,探讨中医“痰浊”与现代医学磷酸化Tau蛋白异常聚集的相关性,并从UPS视角提出益气化痰开窍法治疗AD的作用机制假说,推测UPS可能是远志散益气化痰开窍干预AD的主要途径,精确调控UPS可能是未来研究防治AD的新视角,为科学阐释通过调控UPS蛋白降解途径治疗AD的作用机制提供新思路。  相似文献   
99.
The Sláintecare report developed by political consensus sets out a ten year plan for achieving Universal Health Care (UHC) in Ireland. This paper evaluates the design and progress of the report to mid 2020, but with some reflection on the new COVID 19 era, particularly as it relates to the expansion of entitlements to achieve UHC. The authors explore how close Sláintecare is to the UHC ideal. They also review the phased strategy of implementation in Sláintecare that utilises a systems-thinking approach with interlinkages between entitlements, funding, capacity and implementation. Finally the authors review the Sláintecare milestones against the reality of implementation since the publication of the report in 2017, cognisant of government policy and practice. Some of the initial assumptions around the context of Sláintecare were not realised and there has been limited progress made toward expanding entitlements, and certainly short of the original plan. Nevertheless there have been positive developments in that there is evidence that Government’s Implementation Strategy and Action Plans are focussing on reforming a complex adaptive system rather than implementing a blueprint with such initiatives as integrated care pilots and citizen engagement. The authors find that this may help the system change but it risks losing some of the essential elements of entitlement expansion in favour of organisational change.  相似文献   
100.
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