Change in hippocampal theta oscillation associated with multiple lever presses in a bimanual two-lever choice task for robot control in rats.

Hippocampal theta oscillations have been implicated in working memory and attentional process, which might be useful for the brain-machine interface (BMI). To further elucidate the properties of the hippocampal theta oscillations that can be used in BMI, we investigated hippocampal theta oscillations during a two-lever choice task. During the task body-restrained rats were trained with a food reward to move an e-puck robot towards them by pressing the correct lever, ipsilateral to the robot several times, using the ipsilateral forelimb. The robot carried food and moved along a semicircle track set in front of the rat. We demonstrated that the power of hippocampal theta oscillations gradually increased during a 6-s preparatory period before the start of multiple lever pressing, irrespective of whether the correct lever choice or forelimb side were used. In addition, there was a significant difference in the theta power after the first choice, between correct and incorrect trials. During the correct trials the theta power was highest during the first lever-releasing period, whereas in the incorrect trials it occurred during the second correct lever-pressing period. We also analyzed the hippocampal theta oscillations at the termination of multiple lever pressing during the correct trials. Irrespective of whether the correct forelimb side was used, the power of hippocampal theta oscillations gradually decreased with the termination of multiple lever pressing. The frequency of theta oscillation also demonstrated an increase and decrease, before and after multiple lever pressing, respectively. There was a transient increase in frequency after the first lever press during the incorrect trials, while no such increase was observed during the correct trials. These results suggested that hippocampal theta oscillations reflect some aspects of preparatory and cognitive neural activities during the robot controlling task, which could be used for BMI

Ipilimumab-induced hypophysitis involving the optic tracts and tuber cinereum evaluated using 3D fluid-attenuated inversion recovery

Ipilimumab, a human monoclonal antibody against cytotoxic T-lymphocyte antigen 4, was approved by the U.S. FDA (Food and Drug Administration) in 2011 for the treatment of unresectable or metastatic malignant melanoma. Occurrence of hypophysitis, an immune-related adverse event due to ipilimumab use, has been frequently reported. We report a case of ipilimumab-induced hypophysitis involving the optic tracts and tuber cinereum, identified using 3D fluid-attenuated inversion recovery

Advanced multiparametric MRI and FDG-PET/CT in multinodular and vacuolating neuronal tumor: A pathologically confirmed case

Multinodular and vacuolating neuronal tumor (MVNT) is a relatively new disease concept proposed in 2013 and was classified as a separate tumor type in 2021 by the World Health Organization (WHO) classification. MVNT can cause seizures but is a benign disease, with no cases of enlargement or postoperative recurrence reported. Recent reports described advanced MRI features in MVNT cases, but the diagnosis of MVNT is usually based on characteristic MRI findings of clusters of nodules. Here, we report advanced multiparametric MRI and FDG-PET/CT findings in a case of MVNT with epileptiform symptoms that was pathologically confirmed by surgery

Duodenal bleeding outside covered stents identified by selective computed tomography during arteriography that was successfully treated by embolization: A case report

The patient was a man in his 60s who previously underwent placement of covered stents in the duodenum for a duodenal stricture caused by pancreatic cancer invasion. He experienced multiple episodes of hematemesis and hematochezia during hospitalization. Emergency upper and lower gastrointestinal endoscopies were performed but were unable to reveal the bleeding source. Based on these findings, we suspected small intestinal bleeding and emergency angiography was performed for the purpose of hemostasis. Computed tomography during arteriography was performed from the superior mesenteric artery and revealed extravasation outside the covered stents in the descending portion of the duodenum. Angiography of the inferior pancreaticoduodenal artery revealed extravasation in the descending portion of the duodenum, and the inferior pancreaticoduodenal artery was embolized with n-butyl cyanoacrylate. There were no postoperative symptoms indicative of intestinal ischemia or pancreatitis, and there was no rebleeding after embolization. In patients with bleeding outside the duodenal-covered stents, it can be difficult to identify the bleeding source by upper gastrointestinal endoscopy. In this case, selective computed tomography during arteriography and angiography revealed bleeding outside the duodenal-covered stents that was successfully treated by arterial embolization with n-butyl cyanoacrylate

Successful coil embolization of a ruptured aneurysm of the arc of Riolan artery

The arc of Riolan (AOR) is an anastomosis between the middle and left colic arteries. Aneurysms of the AOR are very rare visceral artery aneurysms. A 44-year-old man presented with abdominal pain and loss of consciousness. Computed tomography and angiography showed hemorrhagic ascites around the liver and spleen. An irregularly dilated artery was visible within a hematoma in the upper left region of the abdomen, consistent with a ruptured pseudoaneurysm of the AOR. Transcatheter arterial embolization was performed with microcoils. The patient's abdominal pain disappeared after embolization, and no symptoms of intestinal ischemia were observed. To our knowledge, this is the first case of an AOR aneurysm with AOR dilation due to dissection of the celiac artery that was successfully treated by coil embolization

Increase in the relative and absolute theta power before the first lever press in the right- and left-forelimb trials.

<p>(A) Dynamic power spectra before the first lever press with the right (a, c) or the left (b, d) forelimb in correct trials. The parameters used for the analysis were the same as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192593#pone.0192593.g003" target="_blank">Fig 3</a>. The relative power (a, b) and normalized absolute power (c, d) of each frequency were calculated as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192593#pone.0192593.g003" target="_blank">Fig 3</a>. (B) Increase in the relative (a) and normalized absolute (b) power of theta frequency band (6–9 Hz). The black and dotted lines indicate the data averaged over the right- and left-forelimb trials, respectively, and then over the rats. The shaded areas associated with the lines are standard error of the mean.</p

Electrode position and the hippocampal local field potential (LFP).

<p>(A) Typical electrode position in the dorsal hippocampus. The arrows indicate the tips of the twisted electrode, which were marked electrically after the completion of behavioral experiment. (B) Typical hippocampal LFP data around the lever press. The LFP data in four trials are shown on a longer and shorter time scale in upper and lower traces, respectively. The times before the first lever press are indicated as negative values. Horizontal lines under each LFP trace indicate the lever presses. The rat took a food from the robot after the final lever off, indicated by arrowheads in the upper traces. (C) Typical power spectral density of the hippocampal LFP during a session, plotted in arbitrary units.</p

Change in the theta frequency before the first lever press and after the last lever release.

<p>(A) Increase in the dominant frequency of theta oscillation before the first lever press in the correct and incorrect trials. The filled and open circles indicate the data averaged over the correct and incorrect trials in each rat, respectively, and then over all the rats. (B) Increase in the dominant frequency of theta oscillation before the first lever press (a) and decrease after the final lever off (b) in the right and left forelimb trials. The filled and open squares indicate the data averaged over the right and left trials in each rat, respectively, and then over all the rats. The error-bars indicate the standard error of the mean.</p

Change in hippocampal theta oscillation associated with multiple lever presses in a bimanual two-lever choice task for robot control in rats

<div><p>Hippocampal theta oscillations have been implicated in working memory and attentional process, which might be useful for the brain-machine interface (BMI). To further elucidate the properties of the hippocampal theta oscillations that can be used in BMI, we investigated hippocampal theta oscillations during a two-lever choice task. During the task body-restrained rats were trained with a food reward to move an e-puck robot towards them by pressing the correct lever, ipsilateral to the robot several times, using the ipsilateral forelimb. The robot carried food and moved along a semicircle track set in front of the rat. We demonstrated that the power of hippocampal theta oscillations gradually increased during a 6-s preparatory period before the start of multiple lever pressing, irrespective of whether the correct lever choice or forelimb side were used. In addition, there was a significant difference in the theta power after the first choice, between correct and incorrect trials. During the correct trials the theta power was highest during the first lever-releasing period, whereas in the incorrect trials it occurred during the second correct lever-pressing period. We also analyzed the hippocampal theta oscillations at the termination of multiple lever pressing during the correct trials. Irrespective of whether the correct forelimb side was used, the power of hippocampal theta oscillations gradually decreased with the termination of multiple lever pressing. The frequency of theta oscillation also demonstrated an increase and decrease, before and after multiple lever pressing, respectively. There was a transient increase in frequency after the first lever press during the incorrect trials, while no such increase was observed during the correct trials. These results suggested that hippocampal theta oscillations reflect some aspects of preparatory and cognitive neural activities during the robot controlling task, which could be used for BMI.</p></div