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ABSTRACT Recently, optically pumped magnetometers (OPMs), which use the spin polarization of alkali metal atoms to measure magnetic fields, have attracted much attention. However, in order to realize high‐sensitivity biomagnetic field measurements using OPMs, it is necessary to reduce environmental magnetic noise and system noise. In this study, we investigate the effectiveness of the noise reduction of OPM signals when principal component analysis, independent component analysis, and empirical mode decomposition are used for signal processing. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study was to evaluate visual outcomes between medical treatment alone (MED) and Ahmed glaucoma valve implantation (AGVI) in Shiba dogs with primary angle closure glaucoma (PACG). Procedures: Records of 65 Shiba dogs (104 eyes) with PACG were retrospectively reviewed. Vision was assessed qualitatively using both the menace response and maze testing. The significance of age, sex, intraocular pressure (IOP), and duration of clinical signs (≤72 h or >72 h) at first presentation (V1) was assessed. Eyes with vision at V1 were divided into groups according to subsequent treatment method (MED versus AGVI), and vision as a survival outcome was compared between group by the Kaplan–Meier method. Results: At V1, 65 eyes (62.5%) of 54 dogs had vision. There was no statistically significant difference in age or sex on the presence of vision at V1. Median IOP was higher in blind (52 mmHg) compared to sighted eyes (28 mmHg) (p <.001). Eyes presenting in ≤72 h of the onset of clinical signs were more likely to have vision (86.7%) compared to those presenting after 72 h (44.1%) (p <.001). By the Kaplan–Meier analysis, the cumulative visual retention rate was significantly higher with AGVI than with MED (69.2% vs. 7.7%; p <.01) at 12 months. The median time to visual loss was 39.9 months with AGVI vs. 1.7 months with MED. Conclusions: AGVI resulted in better visual outcomes than MED and should be considered in Shiba dogs with PACG that are visual at the time of presentation and suitable for surgery. [ABSTRACT FROM AUTHOR]

Recent observations beneath Kanto, Japan have shown that seismic activity and seismic attenuation within the overlying continental plate change with time due to drainage caused by slow‐slip events (SSEs) along the upper boundary of the Philippine Sea plate. However, associated changes in rock properties have not been investigated. In this study, we estimate frequency‐dependent shear‐wave anisotropy to provide a detailed insight into the structural change associated with drainage. We perform shear‐wave splitting analysis in frequency ranges of 1–4, 2–6, and 4–8 Hz for 306 earthquakes that occur during September 2009–August 2021 and recorded at the Metropolitan Seismic Observation network. Obtained time differences between fast and slow S waves (delay time) range from almost zero to 0.16–0.18 s, exhibiting spatio‐temporal variation and frequency dependence. The fast S‐wave polarization directions are generally consistent with the direction of the maximum horizontal compressional axis in the study region, which suggests that the observed anisotropy is probably caused by the NE–SW‐oriented fractures developed under the regional stress field. The temporal variation in delay times is correlated with SSEs activity with a lag time of 0.0–0.1 year. Furthermore, comparisons between observed frequency‐dependent delay times and numerical calculation of fracture‐induced anisotropy suggest that the average fracture radius is almost constant (0.30–0.35 m) over time but fracture density temporally varies from 0.025 to 0.035. We infer that the fracture density is probably enhanced by opening of the NE–SW‐oriented fractures during the upward migration of fluids that are expelled from the plate interface. Plain Language Summary: Measurement of shear‐wave polarization anisotropy characterizes the intensity and orientation of fractures within the rocks beneath the Earth's surface. Furthermore, its frequency dependence provides important information for determining the fracture size and density. This study reveals that the strength of anisotropy shows temporal variations associated with the inferred periodic drainage from the subducting slab. We discuss a possible mechanism of the structural change focusing on the frequency dependence of the observed anisotropy and propose that the opening of fractures occurs immediately above the subducting slab following the periodic drainage. The obtained results will provide important constraints on fluid‐rock interaction above the subducting plate interface. Key Points: Shear‐wave splitting analysis in Kanto, Japan suggests that seismic anisotropy is orientated sub‐parallel to the regional stressAnisotropy above the plate interface is enhanced with a lag of 0.0–0.1 years from the occurrence of slow‐slip eventsThe observed frequency‐dependent anisotropy suggests that fractures open responding to drainage from plate interface [ABSTRACT FROM AUTHOR]

Mutations in the gene encoding the transient receptor potential vanilloid member 4 (TRPV4), a Ca2+ permeable nonselective cation channel, cause TRPV4‐related disorders. TRPV4 is widely expressed in the brain; however, the pathogenesis underlying TRPV4‐mediated Ca2+ deregulation in neurodevelopment remains unresolved and an effective therapeutic strategy remains to be established. These issues were addressed by isolating mutant dental pulp stem cells from a tooth donated by a child diagnosed with metatropic dysplasia with neurodevelopmental comorbidities caused by a gain‐of‐function TRPV4 mutation, c.1855C > T (p.L619F). The mutation was repaired using CRISPR/Cas9 to generate corrected isogenic stem cells. These stem cells were differentiated into dopaminergic neurons and the pharmacological effects of folic acid were examined. In mutant neurons, constitutively elevated cytosolic Ca2+ augmented AKT‐mediated α‐synuclein (α‐syn) induction, resulting in mitochondrial Ca2+ accumulation and dysfunction. The TRPV4 antagonist, AKT inhibitor, or α‐syn knockdown, normalizes the mitochondrial Ca2+ levels in mutant neurons, suggesting the importance of mutant TRPV4/Ca2+/AKT‐induced α‐syn in mitochondrial Ca2+ accumulation. Folic acid was effective in normalizing mitochondrial Ca2+ levels via the transcriptional repression of α‐syn and improving mitochondrial reactive oxygen species levels, adenosine triphosphate synthesis, and neurite outgrowth of mutant neurons. This study provides new insights into the neuropathological mechanisms underlying TRPV4‐related disorders and related therapeutic strategies. [ABSTRACT FROM AUTHOR]

Recent observations beneath central Japan have shown that periodic fluid drainage occurs during slow‐slip events (SSEs) based on temporal variations in QP−1 ${Q}_{P}^{-1}$ above the megathrust boundary of the subducting Philippine Sea slab. However, no previous studies have estimated associated QS−1 ${Q}_{S}^{-1}$. A comparison of QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ can provide clues to the mechanism of seismic attenuation because of different propagation characteristics of the two waves. We estimate temporal variations in QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ via spectral analyses of waveform data from November 2009 to August 2021 period. The results indicate that both QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ exhibit temporal variations at about 1‐year periodicity and there are systematic differences between QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ that QS−1 ${Q}_{S}^{-1}$ have smaller values, less insignificant variation, and weaker correlations with SSEs. Furthermore, QP−1/QS−1 ${Q}_{P}^{-1}/{Q}_{S}^{-1}$ increases concurrent with SSEs. These differences suggest that attenuation is caused by the wave‐induced fluid flow. QP−1/QS−1 ${Q}_{P}^{-1}/{Q}_{S}^{-1}$ could be an important parameter for detecting the presence of fluid. Plain Language Summary: Q−1 ${Q}^{-1}$ value, which represents energy dissipation of seismic wave, is an important parameter for detecting the anelastic heterogeneity in subsurface rocks. However, few observational studies have revealed the characteristics of both P‐ and S‐wave attenuation (QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$, respectively) related to the presence of fluids in the crust and the uppermost mantle. This study reveals that both QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ show temporal variations associated with the inferred periodic drainage from the upper surface of a subducting slab but QS−1 ${Q}_{S}^{-1}$ is less fluctuated with time. We discuss a possible attenuation mechanism focusing on the differences in the observed QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ values and propose that the wave‐induced fluid flow (WIFF) may be a dominant control on the increases in attenuation concurrent with the drainage from the megathrust. The obtained results will provide important constraints on attenuation mechanism that is enhanced by the presence of fluid in rocks. Key Points: We estimated the long‐term temporal variations in QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ at 20–45 Hz above the megathrust boundary of the Philippine Sea PlateBoth QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ exhibited temporal variations with about 1‐year periodicity and spatiotemporal correlations with slow‐slip eventsSystematic differences between QP−1 ${Q}_{P}^{-1}$ and QS−1 ${Q}_{S}^{-1}$ may provide important constraints on attenuation mechanism enhanced by fluids [ABSTRACT FROM AUTHOR]

Mitochondrial fission factor (MFF) is an adapter that targets dynamin-related protein 1 from the cytosol to the mitochondria for fission. Loss-of-function MFF mutations cause encephalopathy due to defective mitochondrial and peroxisomal fission 2 (EMPF2). To elucidate the molecular mechanisms that were involved, we analyzed the functional effects of MFF depletion in deciduous teeth-derived dental pulp stem cells differentiating into dopaminergic neurons (DNs). When treated with MFF-targeting small interfering RNA, DNs showed impaired neurite outgrowth and reduced mitochondrial signals in neurites harboring elongated mitochondria. MFF silencing also caused mitochondrial Ca2+ accumulation through accelerated Ca2+ influx from the endoplasmic reticulum (ER) via the inositol 1,4,5-trisphosphate receptor. Mitochondrial Ca2+ overload led DNs to produce excessive reactive oxygen species (ROS), and downregulated peroxisome proliferator-activated receptor-gamma co-activator-1 alpha (PGC-1α). MFF was co-immunoprecipitated with voltage-dependent anion channel 1, an essential component of the ER-mitochondrial Ca2+ transport system. Folic acid supplementation normalized ROS levels, PGC-1α mediated mitochondrial biogenesis, and neurite outgrowth in MFF depleted DNs, without affecting their mitochondrial morphology or Ca2+ levels. We propose that MFF negatively regulates the mitochondrial Ca2+ influx from the ER. MFF-insufficiency recapitulated the EMPF2 neuropathology with increased oxidative stress and suppressed mitochondrial biogenesis. ROS and mitochondrial biogenesis might be potential therapeutic targets for EMPF2. [ABSTRACT FROM AUTHOR]

A competitive neural network (NN) learned by the OLVQ1 algorithm has the potential to produce images for land cover mapping. We propose an extended OLVQ1 that adds learning ratios to the original algorithm. Applying it to SPOT[center dot]XS data, we show that higher mapping accuracies can be obtained compared to those of conventional methods. Index Terms - Land cover mapping, learning vector quantization (LVQ), SPOT[center dot]XS data.

New application of fluorescence probe to detect apoplastic redox radicals from plant roots were sought. This probe can detect radicals selectively. Calibration curve for radicals was obtained using nitrogen monoxide as radical standard produced by NOC7. Apoplastic radicals released constitutively were quantified and the release rate was 60 μmol L−1 h−1. Oxidative burst triggered by chitin was distinguished from constitutive radical release. [ABSTRACT FROM PUBLISHER]

ObjectivesThere are three conceivable reasons for the failure of resective surgery for intractable epilepsy: incomplete resection of the epileptogenic zone including or overlapping with eloquent area (group A); incorrect determination of the epileptogenic zone prior to the first surgery (group B); and the development of a new epileptic focus after the first surgery (group C). We examined the relationship between the reason for failure of initial surgery and patient outcomes after repeated surgical resection. MethodsThe study included 18 patients (5.1%) underwent additional surgery after failure of the initial operation. Post-operative outcomes, complications and other clinical data were collected by retrospective chart review. ResultsFour patients (22.2%) were assigned to group A, 13 (72.2%) were assigned to group B, and 1 patient was assigned to group C (5.6%). Six patients (40.0%) were seizure-free for 2 or more years after additional surgery. In group B, 11 patients underwent additional resection of the cortex adjacent to the previously resected area and 2 underwent re-operation involving a site distant from the previously resected area; notably, the latter 2 patients did not achieve seizure-free status post-surgery. After the first operation, only one patient (group A) experienced transient paresis; after additional surgery, 10 of 18 patients (56%; 3 group A, 6 group B, and 1 group C) experienced various complications. DiscussionAlthough additional resective surgery provided freedom from seizures in about 40% of the patients, it is important to weigh a high risk of complications against possible benefits when considering additional surgery. [ABSTRACT FROM PUBLISHER]

Objective To study a new approach to indocyanine green ( ICG) angiography for contrasting the ocular fundus in cats. Animals studied Six healthy laboratory cats. Procedures Fluorescein ( FLUO) and ICG angiography were performed using an infrared-sensitive charged coupled device-equipped fundus camera on sedated cats. Results At 12.3 ± 3.4 s after ICG administration, the choroidal arteries could be seen extending radially from the optic disk. The choroidal veins became apparent at 16.2 ± 4.1 s alongside the choroidal arteries. Gradual fading of the choroidal vessels began 5.8 ± 1.5 min postdye administration and diffuse fluorescence of the fundus appeared. Diffuse fluorescence of the optic disk faded at about 18.8 ± 2.9 min. Mean arterial blood pressure at 1 and 3 min after ICG administration showed no significant change when compared to pre-administration ( P > 0.05). However, 5 min ( P = 0.054) and 10 min ( P < 0.05) postadministration, a significant drop in blood pressure occurred. The time lapse between FLUO administration and its appearance in the ocular fundus was 15.7 ± 3.8 s. Retinal veins became apparent at 22.0 ± 3.6 s alongside retinal arteries. At 31.2 ± 4.1 s, full venous fluorescence was visualized throughout the entire fundus. Conclusions While FLUO angiography shows only the retinal vessels, ICG angiography enabled visualization of the choroidal vasculature. ICG angiography provides clear resolution while remaining reliable and simple; thus, a combination of ICG and FLUO angiography shows promise as a diagnostic aid for clinical evaluation of various chorioretinal diseases in cats. [ABSTRACT FROM AUTHOR]

Numerous mast cells are present in the choroid, but the effects of mast cell mediators on retinal pigment epithelial (RPE) cells are not well understood. We investigated the influence of mast cell mediators on RPE cells in vitro, focusing on tryptase. Expression of receptors was examined by the reverse transcription polymerase chain reaction. We also assessed production of interleukin 8 and vascular endothelial growth factor (VEGF) after RPE cells were stimulated with mast cell mediators by using an antibody array and enzyme-linked immunosorbent assay. Furthermore, we investigated the influence of tryptase on RPE cell migration and integrity by the scratch assay and the transepithelial resistance. RPE cells expressed protease-activated receptor 2 (PAR2), histamine receptor 1, tumor necrosis factor-α (TNF-α) receptor 1, and CCR 1, 3, 4, 8, and 11. Tryptase, PAR2 agonists, histamine, and TNF-α all enhanced interleukin 8 production by RPE cells, while only tryptase enhanced VEGF production. Tryptase also enhanced expression of phosphorylated extracellular signal-regulated kinases 1/2, resulting in increased migration of RPE cells. However, tryptase did not alter epithelial integrity or the expression of zonula occludens-1 and junctional adhesion molecule-A by RPE cells. Mast cell mediators, especially tryptase, may influence RPE cell inflammation. [ABSTRACT FROM AUTHOR]

Recently, optically pumped atomic magnetometers (OPAMs) replacing superconductive quantum interference device-based magnetometers have attracted a considerable amount of attention. To apply the OPAMs to biomagnetic field measurements, simultaneous multilocation measurements are required. To fulfill the specific requirement, we have developed a hybrid cell, which contains potassium and rubidium atoms. The OPAM with a hybrid cell can enhance the spatial homogeneity due to the suppression of pump-beam absorption. Thus, we can have multiple measurement locations inside a hybrid cell with multiple pump and probe lasers. In this paper, we proposed a novel method to accomplish simultaneous multilocation measurements based on pump-beam modulation. Using two optical choppers, we operated a two-channel OPAM with two modulated pump beams. We investigated the signal strength of the OPAM as a function of modulation frequency and found that the signal strength decreased as the modulation frequency increased. Subsequently, we measured the magnetic field distributions generated from a loop coil to validate the proposed method and could confirm that they showed good agreements with the theoretical values. These results demonstrate the feasibility of the proposed method based on pump-beam modulation. [ABSTRACT FROM AUTHOR]

Hypothalamic hamartoma (HH), composed of neurons and glia without apparent cytologic abnormalities, is a rare developmental malformation in humans. Patients with HH often have characteristic medically refractory gelastic seizures, and intrinsic epileptogenesis within the lesions has been speculated. Herein we provide evidence to suggest that in HH neurons, Ca2+ permeability through α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors is aberrantly elevated. In needle biopsy specimens of HH tissue, field potential recordings demonstrated spontaneous epileptiform activities similar to those observed in other etiologically distinct epileptogenic tissues. In HH, however, these activities were clearly abolished by application of Joro Spider Toxin (JSTX), a specific inhibitor of the Ca2+-permeable AMPA receptor. Consistent with these physiologic findings, the neuronal nuclei showed disappearance of adenosine deaminase acting on RNA 2 (ADAR2) immunoreactivity. Furthermore, examination of glutamate receptor 2 (GluA2) messenger RNA (mRNA) revealed that editing efficiency at the glutamine/arginine site was significantly low. These results suggest that neurons in HH may bear Ca2+-permeable AMPA receptors due to dislocation of ADAR2. [ABSTRACT FROM AUTHOR]

Highly sensitive magnetic sensors for biomagnetic measurements are often used in gradiometers to suppress the magnetic noise from the environment. We propose a differential measurement method in optically pumped atomic magnetometers, where the frequency responses from the two magnetometers are balanced separately and the signals are subtracted. A magnetometer system that has two pairs of pump and probe beams was constructed to confirm the noise reduction experimentally. A general form for the transfer function of the magnetometer was derived and the parameters were experimentally fitted for the two magnetometers. The frequency responses were balanced with the inverse of the transfer function in the frequency domain, and the differential measurement improved the signal-to-noise ratio of the magnetometer system, even when the resonance frequency at the two sensing volumes differed by several hertz. This method considerably relaxes the requirement for the uniformity of the magnetic bias field at the two sensing volumes, which previously needed to be identical. [ABSTRACT FROM PUBLISHER]

We measured the spatial homogeneity of spin polarization, which is directly related to the sensitivity and magnetic linewidth of an optically pumped atomic magnetometer with a hybrid cell of K and Rb atoms. This was done by changing the position of the probe beam. Furthermore, for comparison, we also measured the sensitivity and magnetic linewidth of atomic magnetometers with single K and single Rb cells, and found that optically thick atoms were spin polarized homogeneously with the hybrid cell. Optically thin alkali metal vapor can be spin polarized homogeneously, and the spin polarization transfers to an optically thick alkali metal vapor. An atomic magnetometer with the hybrid cell was found to be more effective in realizing simultaneous signal measurements at different locations with the uniform sensitivity and magnetic linewidth. [ABSTRACT FROM AUTHOR]