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Background: Morphine is a commonly used analgesic drug. However, long-term use of morphine will cause tolerance which limits its clinical application in pain treatment. MicroRNAs (miRNAs) have been reported to be involved in the morphine tolerance, but the underlying mechanism is still poorly understood. Methods: Tail flick test was used to measure the maximum possible effect (MPE). Quantitative real-time PCR was employed to detect miR-26b, BDNF, and Wnt5a expression in rat dorsal root ganglia (DRG). Luciferase report assay was introduced to verify the binding relationship between miR-26b and Wnt5a. BDNF, Wnt5a and β-catenin protein level were tested by western blotting. Results: MiR-26b was down-regulated during the development of morphine tolerance while BDNF was upregulated. Overexpression of miR-26b or BDNF inhibition alleviated morphine tolerance. Wnt5a was directly targeted and inhibited by miR-26b via binding to the 3′-UTR of Wnt5a. The Wnt/β-catenin pathway was active in morphine tolerant rats. Moreover, overexpression of Wnt5a could partially enhance miR-26 mimic-mediated morphine tolerance, while a Wnt5a inhibitor could attenuate the tolerance. Conclusion: The present study demonstrated that miR-26b overexpression alleviated morphine tolerance by inhibiting BDNF via the Wnt/β-catenin pathway in rats, highlighting a promising target for the treatment of morphine tolerance.

This study aimed to explore the effects and function of microRNA-101a-3p (miR-101a-3p) in epilepsy. Rat model of pilocarpine-induced epilepsy was established and the seizure frequency was recorded. Expression of miR-101a-3p and c-Fos in hippocampus tissues of Rat models were detected by qRT-PCR and western blot. Besides, we established a hippocampal neuronal culture model of acquired epilepsy using Mg

Although a previous study reported that propofol had a therapeutic effect in status epilepticus (SE), the mechanisms underlying the effect of propofol in SE remain unclear. The aim of this study was to explore the regulatory mechanisms underlying propofol-induced inhibition of SE. A rat SE model was established using the lithium–pilocarpine injection method. A qRT-PCR and Western blot were utilized to detect the expression of relative molecules. Cell apoptosis was evaluated by a flow cytometry assay. The interaction between miR-15a-5p and NR2B was assessed using a luciferase reporter assay. Propofol inhibited cell apoptosis and increased miR-15a-5p expression both in hippocampal tissues of SE rats and low Mg(2+)-induced hippocampal neurons. Propofol-induced attenuation of apoptosis of low Mg(2+)-induced hippocampal neurons was mediated by miR-15a-5p. miR-15a-5p targeted NR2B and negatively regulated its expression. Propofol downregulated NR2B expression, mediated by miR-15a-5p. In terms of the mechanism of action, propofol suppressed the apoptosis of Mg(2+)-induced hippocampal neurons through the miR-15a-5p/NR2B/ERK1/2 pathway. In vivo experiment suggested that propofol inhibited the apoptosis of hippocampal neurons in SE rats by upregulating miR-15a-5p. In terms of the molecular mechanism of propofol, it appears to inhibit apoptosis of hippocampal neurons in SE through the miR-15a-5p/NR2B/ERK1/2 pathway. The findings provide theoretical support for propofol treatment of SE.

Background The aim of this study is to investigate the role of intraoperative MR imaging in temporal lobe low-grade glioma (LGG) surgery and to report the surgical outcome in our series with regard to seizures, neurological defects, and quality of life. Methods Patients with temporal lobe contrast-nonenhancing gliomas who presented with seizures in the course of their disease were enrolled in our prospective study. We non-randomly assigned patients to undergo intraoperative magnetic resonance imaging (iMRI)-guided surgery or conventional surgery. Extent of resection (EOR) and surgical outcomes were compared between the two groups. Results Forty-one patients were allocated in the iMRI group, and 14 were in the conventional group. Comparable EOR was achieved for the two groups (p = 0.634) although preoperative tumor volumes were significantly larger for the iMRI group. Seizure outcome tended to be better for the iMRI group (Engel class I achieved for 89.7 % (35/39) vs 75 % (9/12)) although this difference was not statistically different. Newly developed neurological deficits were observed in four patients (10.3 %) and two patients (16.7 %), respectively (p = 0.928). Free of seizures and neurological morbidity led to a return-to-work or return-to-school rate of 84.6 % (33/39) vs 75 % (9/12), respectively (p = 0.741). Conclusions Our study provided evidence that iMRI was a safe and useful tool in temporal lobe LGG surgery. Optimal extent of resection contributed to favorable seizure outcome in our series with low morbidity rate, which led to a high return-to-work rate.

To investigate the clinical value of high-field-strength intraoperative magnetic resonance imaging (iMRI) combined with optic radiation neuro-navigation for the resection of temporal lobe low-grade gliomas.From April 2009 to September 2013, 65 patients with temporal lobe low-grade gliomas (WHO grade II) involving optic radiation were operated with iMRI and functional neuro-navigation. Diffusion tensor imaging (DTI) based fiber tracking was used to delineate optic radiation. The reconstructed optic radiations were integrated into a navigation system, in order to achieve intraoperative microscopic-based functional neuro-navigation. iMRI was used to update the images for both optic radiations and residual tumors. Volumetric analyses were performed using 3D Slicer for pre- and intra-operative tumor volumes in all cases. All patients were evaluated for visual field deficits preoperatively and postoperatively. The Student t test was used to evaluate the average rate of extent of resection between groups. Spearman rank correlation analysis was used to assess correlations between predictors and epilepsy prognosis.Preoperative tumor volumes were (78±40) cm3. In 29 cases, iMRI scan detected residual tumor that could be further resected, and extent of resection were increased from 76.2% to 92.7% (t=7.314, P0.01). In 19 cases (29.2%), gross total resection was accomplished, and iMRI contributed directly to 8 of these cases. Postsurgical follow-up period varied from 13 months to 59 months, mean (33±13) months. Tumor progression were observed in 3 patients, newly developed or deteriorated visual field defects occurred in 4 patients (6.2%). For patients with pre-operative seizures, Engel Class I were achieved for 89.7% of them. Spearman rank correlation analysis revealed that seizure outcome (Engel Class) was related to increased excision of ratio (r=-0.452, P=0.004, 95% CI: -0.636--0.261) and larger tumors (r=0.391, P=0.014, 95% CI: 0.178-0.484).With iMRI and functional neuro-navigation, the optic radiation can be accurately located, while extent of resection can be evaluated intra-operatively. This technique is safe and helpful for preservation of visual field for the resection of temporal lobe low-grade gliomas involving optic radiation.

Objective Complicated hydrocephalus, such as trapped fourth ventricle, is challenging. Aqueduct stent placement is a possible alternative to the conventional multiple shunts approach. This article discusses the indications, techniques, and clinical experiences of aqueduct stent placement. Methods We retrospectively analyzed a series of 10 consecutive patients with hydrocephalus and had aqueduct stent placement between February 2009 and May 2014. The clinical and imaging data were collected and the indications, technique, and clinical experience of aqueduct stent placement were analyzed and discussed. Results Among the 10 patients (mean age, 38 years; range, 5 months–69 years), 8 patients harbored an obstructive hydrocephalus caused by aqueductal obstruction. The underlying pathology consisted of intraventricular tumor in 3 patients, intraventricular cysticercosis in 2, and membranous or inflammatory obstruction in 3 patients. Two patients presented with trapped fourth ventricle, which resulted from Dandy-Walker malformation and shunt placement, respectively. Aqueduct stents were placed endoscopically in 8 patients, whereas the other 2 were placed microscopically. There were no deaths due to aqueduct stent placement. Postoperatively, all of the patients showed improvement or resolution of their symptoms. After an average follow-up period of 27 months (range, 1–51 months), recurrence of aqueductal obstruction has not been observed. In 1 patient, there was a complication of transient oculomotor paralysis after aqueduct stent placement. A stent migration was observed in 1 patient after remaining stable for 4 years. Conclusions Aqueduct stent placement is technically feasible and can be useful in selected patients either with endoscopy or open surgery.