Cerebral small vessel disease (cSVD) refers to a group of pathological processes with various etiologies affecting the small vessels of the brain. Most cases are sporadic, with age-related and hypertension-related sSVD and cerebral amyloid angiopathy being the most prevalent forms. Monogenic cSVD accounts for up to 5% of causes of stroke.
View Article and Find Full Text PDFWe encountered a case of multiple system atrophy parkinsonian subtype (MSA-P) with right-dominant parkinsonism in the early stage of the disease. Atrophy of the posterolateral putamen and iron deposition are the neuropathological hallmark of MSA-P. Coronal fluid-attenuated inversion-recovery (FLAIR) images showed atrophy and iron deposition in the left posterior putamen contralateral to the clinical dominant side in the early phase.
View Article and Find Full Text PDFAlthough there are many types of inborn errors of metabolism (IEMs) affecting the central nervous system, also referred to as neurometabolic disorders, individual cases are rare, and their diagnosis is often challenging. However, early diagnosis is mandatory to initiate therapy and prevent permanent long-term neurological impairment or death. The clinical course of IEMs is very diverse, with some diseases progressing to acute encephalopathy following infection or fasting while others lead to subacute or slowly progressive encephalopathy.
View Article and Find Full Text PDFNeuronal intranuclear inclusion disease (NIID) is a slowly progressive neurodegenerative disease and may sometimes present with symptoms of subacute encephalopathy, including fever, headache, vomiting, and loss of consciousness. We present a case of adult-onset NIID with subacute encephalopathy, which is confirmed by skin and brain biopsied. The magnetic resonance imaging findings show cortical swelling and hyperintensities in the right temporooccipital lobes on T2-weighted images and magnetic resonance angiography demonstrates vasodilatations of the right middle cerebral artery and posterior cerebral artery.
View Article and Find Full Text PDFKumar defined duropathies as disorders with dural defects-related cerebrospinal fluid leaks, particularly of spinal anterior dura mater, Superficial (hemo) siderosis (SS) and multisegemental amyotrophy (MSAM) were included in duropathies. Dural defects of SS had two types; one was incomplete closure of the dura in the spinal and cranial operations, the other was a spontaneous defect in the spinal anterior dura mater. In a majority of SS patients, spontaneous dural defects were detected at the levels of C7/Th1 to Th2/Th3 on axial FIESTA (fast imaging employing steady state acquisition) images.
View Article and Find Full Text PDFWe present a new theoretical work for the ultrafast x-ray photoelectron diffraction (UXPD) method to track photodissociation of molecules over the long range in femtosecond time scale. Our theory combines the accurate multicenter description of XPD at short to medium distances and the multiple-scattering XPD approach at larger internuclear separations. Then, the theoretical framework is applied to a demonstration of the UXPD profiles from halogen diatomics undergoing photodissociation.
View Article and Find Full Text PDFWe have successfully determined the internuclear distance of I molecules in an alignment laser field by applying our molecular structure determination methodology to an I 2p X-ray photoelectron diffraction profile observed with femtosecond X-ray free electron laser pulses. Using this methodology, we have found that the internuclear distance of the sample I molecules in an alignment Nd:YAG laser field of 6 × 10 W/cm is elongated by from 0.18 to 0.
View Article and Find Full Text PDFWhen an electron binds to its anti-matter counterpart, the positron, it forms the exotic atom positronium (Ps). Ps can further bind to another electron to form the positronium negative ion, Ps(-) (e(-)e(+)e(-)). Since its constituents are solely point-like particles with the same mass, this system provides an excellent testing ground for the three-body problem in quantum mechanics.
View Article and Find Full Text PDFMultinodular and vacuolating neuronal tumors (MVNT) have been referred to as distinctive neuronal tumors whose characteristic features include multiple nodules localized in the subcortical white matter. MVNT are composed of vacuolating dysplastic neurons reactive to HuC/HuD. A significant overexpression of alpha-internexin (INA) limited to the stroma of nodules was reported in one tumor.
View Article and Find Full Text PDFWe report on the measurement of deep inner-shell 2p X-ray photoelectron diffraction (XPD) patterns from laser-aligned I2 molecules using X-ray free-electron laser (XFEL) pulses. The XPD patterns of the I2 molecules, aligned parallel to the polarization vector of the XFEL, were well matched with our theoretical calculations. Further, we propose a criterion for applying our molecular-structure-determination methodology to the experimental XPD data.
View Article and Find Full Text PDFChronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) syndrome is a clinically and radiologically distinct pontine-predominant perivascular neuroinflammation showing T lymphocyte infiltration. It is assumed to have an autoimmune or other inflammatory mediated pathogenesis. We report the first known case of CLIPPERS in East Asia, characterized by multiple punctate enhancement of the brainstem extending to the bilateral posterior limb of the internal capsule and caudal to the spinal cord conus.
View Article and Find Full Text PDFFormation and oxidation processes of PdZn nanoparticles on ZnO were successfully observed by means of in situ time-resolved X-ray absorption fine structure spectroscopy (XAFS), and the analysis of data on near-edge (XANES) and extended (EXAFS) structures revealed detailed changes in Pd during both processes. PdZn nanoparticles were formed on ZnO through a two-step scheme under a hydrogen atmosphere. The first process was the formation of metallic Pd nanoparticles, which was quickly finished within 1 s.
View Article and Find Full Text PDFWe have performed extensive density functional theory (DFT) calculations, partial cross sections, dipole prepared continuum orbitals, dipole amplitudes and phase shifts, asymmetry parameters β, and molecular frame photoelectron angular distributions, to elucidate the O1s photoionization dynamics of NO(2) molecule with emphasis on the shape resonances in the O1s ionization continuum. In the shape resonance region, the β parameters and photoelectron angular distributions have been compared with our experimental results. Fairly good agreement between the theory and experiment has confirmed that the DFT level calculations can well describe the photoionization dynamics of the simple molecule such as NO(2).
View Article and Find Full Text PDFThe 13th harmonic of a Ti:sapphire (Ti:S) laser in the plateau region was injected as a seeding source to a 250-MeV free-electron-laser (FEL) amplifier. When the amplification conditions were fulfilled, strong enhancement of the radiation intensity by a factor of 650 was observed. The random and uncontrollable spikes, which appeared in the spectra of the Self-Amplified Spontaneous Emission (SASE) based FEL radiation without the seeding source, were found to be suppressed drastically to form to a narrow-band, single peak profile at 61.
View Article and Find Full Text PDFAngular distributions of N 1s photoelectrons from fixed-in-space NO(2) molecules have been measured over the energy region of shape resonance and above. A multiple-coincidence velocity-map imaging technique for observation of molecular frame photoelectron angular distributions (MF-PADs) has been extended to nonlinear molecular targets. Density functional theory calculations have also been conducted to elucidate the photoionization dynamics and shape resonance in the N 1s photoionization of NO(2).
View Article and Find Full Text PDFIntroduction: Hemimegalencephaly is a well-known congenital malformation. However, localized megalencephaly, which may be one of the subtypes of hemimegalencephaly, has not been separately investigated. In the present study, we attempted to characterize the clinical and magnetic resonance (MR) imaging features of localized megalencephaly in comparison with ordinary diffuse hemimegalencephaly and multilobar cortical dysplasia.
View Article and Find Full Text PDFFor K-shell photoionization of neon dimers, we report Ne 1s photoelectron angular distributions for Ne2++Ne+ and Ne++Ne+ channels exhibiting quite different patterns. Noninversion-symmetric patterns of the former obtained by the fast interatomic Coulombic decay of Auger final states show direct evidence of core-hole localization. Dipolar patterns of the latter obtained by the slow radiative decay of the other Auger final states clearly show that the radiative process is slow enough to allow dicationic dimers to rotate many times before fragmentation.
View Article and Find Full Text PDFCortical dysplasia (CD) is a malformation predominantly affected cerebral neocortex, resulting in disorganized brain cytoarchitecture. Normal cortical lamination is disturbed and neurons are abnormally located. Adjacent white matter is often involved.
View Article and Find Full Text PDFAs neurosurgical treatments have been increasingly applied to patients who have intractable epilepsy, much knowledge on pathological changes in surgically removed brain tissues have become clearer in recent years, as well as on the neuroimaging findings which are analyzed with a variety of techniques, including computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), single photon emission computed tomography (SPECT) in combination with digital imaging and communication in medicine (DICOM), statistical parametric mapping (SPM), subtraction ictal SPECT coregistered to MRI (SISCOM) and/or PET-guided intraoperative navigation system, as mentioned in detain in another article in this issue by Maehara et al. Representative and relatively common diseases, treated by epilepsy-surgery, are as follows; hippocampal sclerosis, amygdaloid sclerosis, coarse and macroscopic brain malformation (focal cortical dysplasia, hemimegalencephaly, tuberous sclerosis), tumors (dysembryoplastic neuroepithelial tumor, ganglioglioma, etc.), destructive lesions and the others.
View Article and Find Full Text PDFIntroduction: Diagnosing corticobasal degeneration is often difficult on the basis of clinical symptoms and radiological images. We aimed to clarify the imaging findings of corticobasal degeneration syndrome (CBDS).
Methods: Included in the study were 16 patients (8 men, 8 women, 46-75 years old) with clinically diagnosed CBDS.
We report a 66-year-old woman with a presyrinx state due to adhesive arachnoiditis. She had a history of subarachnoid hemorrhage one year ago. She became aware of gait disturbance and abnormal sensation at the chest 6 months ago.
View Article and Find Full Text PDFObject: Epilepsy in patients with bihemispheric malformations of cortical development (MCD) is typically medically intractable. Focal resection has been reported to be ineffective. Corpus callosotomy has been advocated as a treatment option, but the results have been reported only in several case reports.
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