Deuterium isotope effects on interaction energies and geometrical parameters in several HO(DO)ene and HO+(DO)yne complexes, which involve O-H(D)π interactions, have been analyzed using the MP2 level of the multi-component molecular orbital method (MC_MP2), which can incorporate the nuclear quantum effects of light nuclei, such as protons and deuterons. The MC_MP2 calculations revealed that DO replacement reduced the interaction energies of the complexes and induced changes in geometrical parameters. In addition, natural energy decomposition analysis (NEDA) revealed a strong correlation between the H/D isotope effects on the H/Dπ distances and on each energy component.
View Article and Find Full Text PDFPurpose: The preoperative assessment of carotid plaques is necessary to render revascularization safe and effective. The aim of this study is to evaluate the usefulness of chemical exchange saturation transfer (CEST)-MRI, particularly amide proton transfer (APT) imaging as a preoperative carotid plaque diagnostic tool.
Methods: We recorded the APT signal intensity on concentration maps of 34 patients scheduled for carotid endarterectomy.
By introducing main-group elements such as boron and bismuth to π-conjugated systems, it is possible to modify the optical properties of π-conjugated materials through orbital interactions between the orbital on the elements and π/π*-orbitals, and the heavy atom effect. Moreover, bismuth, which is the heaviest stable element, induces a significant heavy atom effect, making organobismuth compounds promising for applications as phosphorescent materials. In this study, we synthesized new room-temperature phosphorescent materials by incorporating bismuth into thiophene units.
View Article and Find Full Text PDFThe colorless solution of furan-2-yl bis(indolyl)methane (BIM) is newly revealed to work as a palladium (Pd) ion-selective chromogenic agent by turning orange. 5-(-Methyl--phenyl-aminomethyl)-furan-2-yl BIM could be synthesized from 5-chloromethylfurfural as a biorenewable feedstock one-pot and double functionalization, and a mixture of its solution and Pd ions showed the highest absorbance at 465 nm in UV-Vis analysis. On the other hand, other metal ions (Cu, Cr, Cr, Fe, Fe, Ni, Zn, In, Pt, or Ce) exhibited no response.
View Article and Find Full Text PDFPurpose: Non-convulsive status epilepticus (NCSE) is characterized by repetitive or continuous seizures without convulsions. Arterial spin labeling (ASL) is useful for assessing hyperperfusion due to neurovascular unit coupling in patients with NCSE; subarachnoid hemorrhage (SAH) impairs the neurovascular unit. We hypothesized that the sensitivity of ASL in detecting NCSE is low in patients with SAH during the acute phase.
View Article and Find Full Text PDFBackground: A rete mirabile is a rare vascular anomaly, with posterior cerebral artery (PCA) involvement being especially rare. Its pathogenesis has been speculated as a remnant of "distal annexation" between the primitive anterior choroidal artery (AchA) and the PCA at this site, but the exact mechanisms remain unclear.
Observations: A 29-year-old man presented with subarachnoid hemorrhage.
The gain of the microchannel plate temporally drops after an ion initiates an electron avalanche. Electron multiplication was expected to deplete the charge from the microchannel wall and produce the depleted charge (wall charge). Moreover, it was reported that the gain drop occurred not only in the activated channels, where the electrons are multiplied, but also in the surrounding channels.
View Article and Find Full Text PDFBackground: We present the case of an individual with acute occlusion of the middle cerebral artery caused by atherosclerosis. The patient underwent angioplasty using a coronary perfusion balloon, which resulted in a favorable clinical outcome.
Case Description: A 66-year-old male patient presented with an acute onset of right hemiplegia and dysarthria.
Ice is the most fundamental hydrogen-bonded system in which the hydrogen nuclear quantum effect significantly impacts the structure and relevant thermochemical and spectroscopic properties. While ice was experimentally investigated using proton nuclear magnetic resonance spectroscopy more than 40 years ago, the corresponding theoretical investigations have been rarely reported due to the difficulty in evaluating how the proton nuclear quantum effect influences the spectral characteristics of such a condensed material. In this study, we applied a combination of the ONIOM and multicomponent molecular orbital (MC_MO) methods for calculating the anisotropic and isotropic components of the nuclear magnetic shielding tensor of the hexagonal ice crystal to quantify the effects of nuclear quantum fluctuations on the spectroscopic properties of ice.
View Article and Find Full Text PDFBackground: We report two cases who underwent mechanical thrombectomy using a stent retriever in advance of urgent carotid artery stenting (CAS) for carotid artery stenosis with free-floating thrombus (FFT).
Case Description: Two patients showing symptomatic carotid artery stenosis with FFT underwent urgent endovascular surgery due to progressive neurological symptoms. The first case showed an FFT with 70% internal carotid artery (ICA) stenosis.
Background And Objectives: Intravenous indocyanine green (IV-ICG) videoangiography is commonly performed to detect blood flow in the microscopic view. However, intra-arterial ICG (IA-ICG) videoangiography provides high-contrast imaging, repeatability within a short period of time, and clear-cut separation of the arterial and venous phases compared with IV-ICG. These features are useful for detecting retrograde venous drainage (RVD) and shunt occlusion in arteriovenous fistulae (AVF) surgery.
View Article and Find Full Text PDFBackground: Intravenous recombinant tissue plasminogen activator (IV rt-PA) and endovascular treatment have been performed for severe large vessel occlusion (LVO) and the results have been reported at high levels of evidence. However, acute treatment for LVO with mild symptom remains controversial. We retrospectively examined prognostic factors for LVO with mild symptoms.
View Article and Find Full Text PDFBackground: Cerebral microbleeds (CMBs) due to traumatic brain injuries (TBI) have been shown to lead to cognitive decline and impairment. CMBs caused by TBI may be associated with pathophysiological mechanisms involving inflammation and the accumulation of amyloid-β (Aβ), tau, and phosphorylated tau (p-tau), contributing to cognitive abnormalities. However, their relationships remain unclear.
View Article and Find Full Text PDFStructure-function relationships in proteins have been one of the crucial scientific topics in recent research. Heme proteins have diverse and pivotal biological functions. Therefore, clarifying their structure-function correlation is significant to understand their functional mechanism and is informative for various fields of science.
View Article and Find Full Text PDFMyoepithelial carcinoma of the nasal cavity is extremely rare. We report the case of a 66-year-old man with myoepithelial carcinoma of the nasal cavity. Computed tomography (CT) and magnetic resonance imaging revealed a lobulated soft tissue mass with central necrosis and hemorrhage, as well as an invasion of the skull base and left orbit.
View Article and Find Full Text PDFObjective: An understanding of the complex morphology of an arteriovenous malformation (AVM) is important for successful resection. We have previously reported the utility of intra-arterial indocyanine green (ICG) videoangiography for this purpose, but that method cannot detect the angioarchitecture covered by brain tissue. 3-dimensional (3D) multimodal fusion imaging is reportedly useful for this same purpose, but cannot always visualize the exact angioarchitecture due to poor source images and processing techniques.
View Article and Find Full Text PDFThe major cytoskeleton protein actin undergoes cyclic transitions between the monomeric G-form and the filamentous F-form, which drive organelle transport and cell motility. This mechanical work is driven by the ATPase activity at the catalytic site in the F-form. For deeper understanding of the actin cellular functions, the reaction mechanism must be elucidated.
View Article and Find Full Text PDFHeme proteins serve diverse and pivotal biological functions. Therefore, clarifying the mechanisms of these diverse functions of heme is a crucial scientific topic. Distortion of heme porphyrin is one of the key factors regulating the chemical properties of heme.
View Article and Find Full Text PDFBackground: Convexity dural arteriovenous fistulae (dAVF) usually reflux into cortical veins without involving the venous sinuses. Although direct drainage ligation is curative, transarterial embolization (TAE) may be an alternative treatment.
Case Description: Between September 2018 and January 2021, we encountered four patients with convexity dAVFs.
Revascularization for common carotid artery (CCA) occlusion might be difficult. We reported our strategy for revascularizing CCA occlusion by giant clots. A 94-year-old woman was transferred to our hospital because of right hemiparesis and aphasia.
View Article and Find Full Text PDFBackground: Dural arteriovenous fistula (DAVF) can present with massive hematoma, which sometimes requires emergent removal. Therefore, a surgical strategy for single-session hematoma removal and shunt occlusion in the same surgical field is important.
Observations: A 73-year-old man was transferred to the authors' hospital with a headache.
Background: Sufficient understanding of the angioarchitecture of an arteriovenous fistula (AVF) at the craniocervical junction (CCJ) is crucial to surgical treatment but is often difficult because of the complex vascular anatomy. Intraarterial indocyanine green (ICG) videoangiography has emerged as a more useful option for understanding the vascular anatomy than intravenous ICG videoangiography. This report describes two cases of CCJ AVFs successfully treated by surgery using intraarterial ICG videoangiography and describes the efficacy of this technique.
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