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Although reactive oxygen species (ROS) are known to have harmful effects in organisms, recent studies have demonstrated expression of ROS synthases at various parts of the organisms and the controlled ROS generation, suggesting possible involvement of ROS signaling in physiological events of individuals. However, physiological roles of ROS in the CNS, including functional roles in higher brain functions or neuronal activity-dependent ROS production, remain to be elucidated. Here, we demonstrated involvement of ROS – 8-NO₂-cGMP signaling in motor learning and synaptic plasticity in the cerebellum. In the presence of inhibitors of ROS signal or ROS synthases, cerebellar motor learning was impaired, and the stimulus inducing long-term depression (LTD), cellular basis for the motor learning, failed to induce LTD but induced long-term potentiation (LTP)-like change at cerebellar synapses. Furthermore, ROS was produced by LTD-inducing stimulus in enzyme-dependent manner, and excess administration of the antioxidant vitamin E impaired cerebellar motor learning, suggesting beneficial roles of endogenous ROS in the learning. As a downstream signal, involvement of 8-NO₂-cGMP in motor learning and cerebellar LTD were also revealed. These findings indicate that ROS – 8-NO₂-cGMP signal is activated by neuronal activity and is essential for cerebellum-dependent motor learning and synaptic plasticity, demonstrating involvement of the signal in physiological function of brain systems.

The aim of this study was to analyze the clinical and radiological characteristics of glioblastomas (GBMs) harboring a BRAF mutation. Sequencing analysis of BRAF, IDH1/2, and TERT promoters was performed on GBM samples of patients older than 15 years. The clinical, pathological, and radiological data of patients were retrospectively reviewed. Patients were classified into three groups according to their BRAF and IDH1/2 status: BRAF group, IDH group, and BRAF/IDH-wild-type (WT) group. Among 179 GBM cases, we identified nine cases with a BRAF mutation and nine with IDH mutation. The WT group had 161 cases. Age at onset in the BRAF group was significantly lower compared to the WT group and was similar to the IDH group. In cases with negative IDH1-R132H staining and age < 55 years, 15.2% were BRAF-mutant cases. Similar to the IDH group, overall survival of the BRAF group was significantly longer compared with the WT group. Among nine cases in the BRAF group, three cases had hemorrhagic onset and prior lesions were observed in two cases. In conclusion, age < 55 years, being IDH1-R132H negative, with hemorrhagic onset or the presence of prior lesions are factors that signal recommendation of BRAF analysis for adult GBM patients.

Objective: Lumbar drains (LD) have been identified to cause brain sag (BS), which is a serious intracranial hypotension that causes coma; however, other contributing risk factors should also be considered. Therefore, this study aims to identify the BS risk factors and determine the proper treatment plan after brain tumor surgery for patients with BS. Methods: This retrospective study included patients who underwent brain tumor surgery between 2011 and 2015. BS was diagnosed based on the clinical signs of cerebrospinal fluid hypovolemia along with the radiological findings of the basal cistern effacement. Based on the data on the clinical features, the symptoms were used to determine the BS risk factors using logistic regression. Results: Overall, among the 412 patients included in this study, 12 (2.91%) were found to develop BS, 10 experienced altered consciousness, and 2 experienced orthostatic headaches. In all cases, radiological images at onset showed epidural/subdural fluid collection, along with basal cistern effacement. LD was inserted just before surgery in 11 cases, while a ventriculoperitoneal shunt was placed in one patient. The treatment strategies used are as follows: Ringer's solution infusion (n = 4), Trendelenburg position (n = 2), intrathecal injection of saline (n = 1), or no care due to misdiagnosis (n = 5). Moreover, the significant BS risk factors were determined to be the LD (odds ratio [OR] 30.70, CI 2.77-339.86), supratentorial skull base approach (SBA) (OR 35.71, CI 9.1922-138.7250), surgical time (1693.07, CI 69.5621-41207.448), and postoperative hyperosmotic diuretic use (OR 8.092, CI 2.485-26.345) after surgery. Conclusions: In the brain tumor surgery, aside from the LD, the application of supratentorial SBA, use of HD, and lengthy surgery are also found to be contributing risk factors for BS. Therefore, BS should be considered in the differential diagnosis of high-risk patients with postoperative altered consciousness.

Wheel slip prediction on rough terrain is crucial for secure, long-term operations of planetary exploration rovers. Although rough, unstructured terrain hampers mobility, prediction by modeling wheel–terrain interactions remains difficult owing to unclear terrain conditions and complexities of terramechanics models. This study proposes a vision-based approach with machine learning for predicting wheel slip risk by estimating the slope from 3D information and classifying terrain types from image information. It considers the slope estimation accuracy for risk prediction under sharp increases in wheel slip due to inclined ground. Experimental results obtained with a rover testbed on several terrain types validate this method.