Intraoperative neuromonitoring with direct cortical stimulation motor-evoked potentials in supratentorial glioma surgeries with preoperative moderate-to-severe motor weakness.

Purpose: Intraoperative neuromonitoring (IONM) is essential for safe brain tumor surgeries. Little is known about how to assess damaged motor function. To preserve damaged motor function in these patients, we evaluated the results of direct cortical stimulation motor-evoked potential (D-MEP) monitoring in glioma surgeries performed in and near the primary motor cortex (PMC) and cortico-spinal tract (CST).

Concomitant using bulbocavernosus reflex and motor-evoked potential from the external anal sphincter improves continuous monitoring for urinary function assessment during untethering surgery in children.

Purpose: Intraoperative monitoring can be used to prevent postoperative urinary dysfunction due to surgical manipulation. However, preoperative neurological dysfunction and young age make monitoring challenging. Therefore, in this study, we evaluated the efficacy of combining two monitoring methods, the bulbocavernosus reflex (BCR) and motor-evoked potential from the external anal sphincter (EAS-MEP) in assessing urinary function in the same pediatric patients during untethering surgery.

Accessing Single-Molecule Properties of Heptacene Using a Metal-Organic Framework.

Acenes, classic polycyclic aromatic hydrocarbons composed of linearly fused benzene rings, represent a model system for exploring the physical properties of 1D π-conjugated structures. Isolating individual molecules at the single-molecule level provides a means to investigate their intrinsic properties, which is typically done by dissolving in solutions. However, this approach becomes increasingly difficult to apply for higher acenes owing to their high insolubility and instability.

Exploring the chemistry of higher acenes: from synthesis to applications.

This review explores the advancements in the chemistry of higher acenes and their derivatives, with a focus on their synthesis, characterization, and potential applications. Historically, higher acenes have presented challenges to study due to their inherent instability and reactivity under ambient conditions. However, innovative synthetic strategies, including on-surface synthesis and the precursor approach, have significantly contributed to the ability to synthesize higher acenes even at preparative scales while evaluating their magnetic and semiconducting properties.

Intraoperative transcranial facial motor evoked potential in vestibular schwannoma reflects short-term post operative facial nerve function.

Preservation of facial nerve function is extremely important in vestibular schwannoma surgery. Intraoperative transcranial facial motor evoked potential (Tc-fMEP) monitoring was used, and its accuracy and the correlations of Tc-fMEP results with postoperative facial nerve function at various time points were investigated. Factors associated with postoperative deterioration of facial nerve function were also examined.

Usefulness of piezoelectric sensor device for monitoring extraocular movement during endoscopic endonasal surgery to remove skull base tumor.

The present study was conducted to evaluate three modalities used to detect extraocular movement during endonasal endoscopic surgery for a skull base tumor to protect cranial nerves from damage; free-run electrooculography (EOG), piezoelectric sensor (PES), and triggered electromyography (t-EMG) monitoring. Twenty patients (8 males, 12 females; average age 61.8 years) treated for a skull base tumor at Nara Medical University from 2018 to 2021 were enrolled.

Shape-Persistent Anthracene-Based Macrocycles Prepared by Reversible Boronic Ester Formation: Crystallization and Structural Analysis.

Shape-persistent macrocycles with confined inner spaces have gained significant interest due to their unique properties and potential applications in gas/molecular recognition, nanoscale templates, and nanoelectronics. In this study, we present an efficient synthesis of macrocycles containing anthracene units through reversible boronic ester formation between 1,2-diols and boronic acids. These template-free macrocycles exhibited diverse internal cavities ranging from 11 Å to 20 Å and readily crystallized in solution and on solid substrates.

Fine-Tuning of the Sequential Self-Assembly of Entangled Polyhedra by Exploiting the Side-Chain Effect.

The control of the sequential self-assembly processes of highly entangled (AgL) (n=2,4,6,8) and AgL coordination polyhedra using side-chain effects was studied via the introduction of linear or branched side chains into the tripodal ligands. In addition to changes in the intermediate polyhedral species affording the multi- pathway process, disruption of the kinetic control of the sequential self-assembly was observed, thus demonstrating the utility of steric control for the construction of 3D-entangled molecular materials on the 5 nm scale with high molecular complexity.

Orderly Arranged Cubic Quantum Dots along Supramolecular Templates of Naphthalenediimide Aggregates.

Precise control of assembled structures of quantum dots (QDs) is crucial for realizing the desired photophysical properties, but this remains challenging. Especially, the one-dimensional (1D) control is rare due to the nearly isotropic nature of QDs. Herein, we propose a novel strategy for controlling the 1D-arrangement range of cubic perovskite QDs in solution based on the morphological modification of a supramolecular polymer (SP) template.

Structure and Defect Identification at Self-Assembled Islands of CO Using Scanning Probe Microscopy.

Understanding how carbon dioxide (CO) behaves and interacts with surfaces is paramount for the development of sensors and materials to attempt CO mitigation and catalysis. Here, we combine simultaneous atomic force microscopy (AFM) and scanning tunneling microscopy (STM) using CO-functionalized probes with density functional theory (DFT)-based simulations to gain fundamental insight into the behavior of physisorbed CO molecules on a gold(111) surface that also contains one-dimensional metal-organic chains formed by 1,4-phenylene diisocyanide (PDI) bridged by gold (Au) adatoms. We resolve the structure of self-assembled CO islands, both confined between the PDI-Au chains as well as free-standing on the surface and reveal a chiral arrangement of CO molecules in a windmill-like structure that encloses a standing-up CO molecule and other foreign species existing at the surface.

Intraoperative Neuromonitoring for the Lower-Extremity Region Using Motor-Evoked Potential With Direct Cortical Stimulation in Brain Tumor Surgeries.

Purpose: To evaluate the motor function of the lower extremity (LE), we used direct cortical stimulation motor-evoked potential (D-MEP) monitoring with a single six-contact subdural strip electrode placed in the interhemispheric fissure.

Methods: Intraoperative neuromonitoring using D-MEPs in the LE was performed in 18 cases (16 patients) for brain tumor surgery from December 2018 to April 2023 with a follow-up period of at least 3 months. After dural opening, a single six-contact subdural strip electrode was placed inside the interhemispheric fissure.

On-Surface Synthesis of Triaza[5]triangulene through Cyclodehydrogenation and its Magnetism.

Triangulenes as neutral radicals are becoming promising candidates for future applications such as spintronics and quantum technologies. To extend the potential of the advanced materials, it is of importance to control their electronic and magnetic properties by multiple graphitic nitrogen doping. Here, we synthesize triaza[5]triangulene on Au(111) by cyclodehydrogenation, and its derivatives by cleaving C-N bonds.

Which patients do we need to consider augmentation of muscle active potentials regarding transcranial electrical stimulation motor-evoked potentials monitoring before spine surgery?

Background Context: Transcranial electrical stimulation motor-evoked potentials (Tc-MEPs) are the current trend and are important in preventing intraoperative neurological deficits. Posttetanic Tc-MEPs (p-MEP) can augment the amplitudes of compound muscle active potentials (CMAPs), especially in the case of insufficient conventional Tc-MEPs (c-MEP).

Purpose: To retrospectively investigate pre- and intraoperative factors necessitating p-MEP monitoring and to examine changes in the success rates of baseline Tc-MEP monitoring before and after tetanic stimulation in patients with such factors.

Unilateral abnormality of initial motor-evoked potential in the upper limb detected during lumbar spine surgery: a case report.

Background: We present a case with abnormal findings of initial motor-evoked potential (MEP) in the left upper limb after prone positioning during lumbar spine surgery.

Case Presentation: A 71-year-old man with bilateral lower extremity numbness without a history of preexisting motor weakness underwent L3-5 spinal fenestration. Initial MEP monitoring after prone positioning revealed markedly prolonged latency and lower amplitude in the left abductor pollicis brevis (APB).

Quantitative Analysis of Photochemical Reactions in Pentacene Precursor Films.

On-surface reactions are rapidly gaining attention as a chemical technique for synthesizing organic functional materials, such as graphene nanoribbons and molecular semiconductors. Quantitative analysis of such reactions is essential for fabricating high-quality film structures, but until our recent work using p-polarized multiple-angle incidence resolution spectrometry (pMAIRS), no analytical technique is available to quantify the reaction rate. In the present study, the pMAIRS technique is employed to analyze the photochemical reaction from 6,13-dihydro-6,13-ethanopentacene-15,16-dione to pentacene in thin films.

Complexation study of a 1,3-phenylene-bridged cyclic hexa-naphthalene with fullerenes C and C in solution and 1D-alignment of fullerenes in the crystals.

To investigate the host ability of a simple macrocycle, 1,3-phenylene-bridged naphthalene hexamer N6, we evaluated the complexation of N6 with fullerenes in toluene and in the crystals. The complexes in the solid-state demonstrate the one-dimensional alignment of fullerenes. The single-crystals of the C@N6 composite have semiconductive properties revealed by photoconductivity measurements.

Effect of Sevoflurane Anesthesia on Intraoperative Spikes, High-Frequency Oscillations, and Phase-Amplitude Coupling in MRI-Normal Hippocampus.

Purpose: The purpose of this study was to determine the effect of sevoflurane anesthesia on spikes, high-frequency oscillations (HFOs), and phase-amplitude coupling using a modulation index in MRI-normal hippocampus, with the aim of evaluating the utility of intraoperative electrocorticography in identifying the epileptogenic hippocampus during sevoflurane administration.

Methods: Eleven patients with intractable temporal lobe epilepsy with a normal hippocampus on MRI underwent extra-operative electrocorticography evaluation. Patients were assigned to the Ictal (+) or Ictal (-) group depending on whether the parahippocampal gyrus was included in the seizure onset zone.

Utility of desflurane as an anesthetic in motor-evoked potentials in spine surgery and the facilitating effect in tetanic stimulation of bilateral median nerves.

Although desflurane is a safe and controllable inhalation anesthetic used in spinal surgery, to our knowledge, there have been no reports of successful motor-evoked potential (MEP) recordings under general anesthesia with desflurane alone. A high desflurane concentration may reduce the risk of intraoperative awareness but can also reduce the success of MEP recording. Therefore, we aimed to evaluate the reliability of MEP monitoring and investigate whether tetanic stimulation can augment MEP amplitude under general anesthesia with high-concentration desflurane during spinal surgery.

Buckybowl and its chiral hybrids featuring eight-membered rings and helicene units.

Here we report the synthesis of a novel buckybowl (7) with a high bowl-to-bowl inversion barrier (Δ = 38 kcal mol), which renders the rate of inversion slow enough at room temperature to establish two chiral polycyclic aromatic hydrocarbons (PAHs). By strategic fusion of eight-membered rings to the rim of 7, the chiral hybrids 8 and 9 are synthesized and display helicity and positive and negative curvature, allowing the enantiomers to be configurationally stable and their chiroptical properties are thoroughly examined. Computational and experimental studies reveal the enantiomerization mechanisms for the chiral hybrids and demonstrate that the eight-membered ring strongly affects the conformational stability.

An Unsymmetrical 5,15-Disubstituted Tetrabenzoporphyrin: Effect of Molecular Symmetry on the Packing Structure and Charge Transporting Property.

Molecular design strategy to control the crystal structure of two-dimensional (2D) π-extended organic semiconductors has not been intensively explored. We synthesized an unsymmetric tetrabenzoporphyrin derivative (TIPS-Ph-BP) to demonstrate the effect of molecular symmetry on crystal packing. TIPS-Ph-BP formed an antiparallel slipped π-stacking and 2D herringbone-like structure.

Application of laser speckle flowgraphy to evaluate cerebral perfusion after carotid endarterectomy.

Cerebral hyperperfusion syndrome (CHS) after carotid endarterectomy (CEA) is devastating, and postoperative monitoring of cerebral perfusion is essential to prevent CHS. We report two cases of successful measurement of ocular blood flow using laser speckle flowgraphy (LSFG) for bedside assessment of the changes in cerebral perfusion after CEA. An 18.

Effects of intraoperative motor evoked potential amplification following tetanic stimulation of the pudendal nerve in pediatric craniotomy.

Objective: Monitoring the intraoperative motor evoked potentials (MEPs) in pediatric craniotomy is challenging because of its low detection rate, which makes it unreliable. Tetanic stimulation of the peripheral nerves of the extremities and pudendal nerves prior to transcranial electrical stimulation (TES) or direct cortical stimulation (DCS) amplifies the MEPs. The authors investigated the effects of MEP amplification following tetanic stimulation of the median and tibial nerve or the pudendal nerve in pediatric patients undergoing craniotomy.