186 research outputs found

    Wavelet Correlation Analysis for Quantifying Similarities and Real-Time Estimates of Information Encoded or Decoded in Single-Trial Oscillatory Brain Waves

    Get PDF
    Even in cases when we recognize identical objects or when we behave similarly, the spatiotemporal activities in the brain are likely to fluctuate to various degrees. Temporally fluctuating responses easily decrease by averaging replicate measures. We previously developed a wavelet correlation analysis that tolerates the across-trial oscillatory phase variability observed in odor-induced cortical responses. The wavelet correlation analysis revealed a change in the neuronal information redundancy of transient and oscillatory brain waves from the dependencies on stimulus experience (high redundancy) to stimulus quality (low redundancy) between the input and output layers of the anterior piriform cortex in guinea pigs. We report on its application to estimate information in the fine temporal structures of single-trial brain waves. By using a set of standard brain waves for each information in a given category, the highest wavelet correlation coefficients provided the first candidate of estimated information with 75% accuracy. Moreover, the probability of including the correct information for the two upper candidates, regardless of information redundancy of the signal sources, was >92%. The wavelet correlation analysis is useful for similarity analyses and real-time estimates of in-brain information and for its application to brain-machine interfaces or medical/research tools

    Novel method for evaluation of anaerobic germination in rice and its application to diverse genetic collections

    Get PDF
    Direct seeding saves time and labour in the cultivation of rice. However, seedling establishment is often unstable, and yields are lower than in transplanting. Anaerobic germination (AG) is a key trait for improvement of direct seeding of rice. We established a simple and reliable method of evaluating AG in rice breeding. We germinated seeds in distilled water or deoxygenated water and measured coleoptile length several days later; compared the results of each method with survival rate in flooded soil; and used the anoxic water method for QTL analysis and for testing cultivars. Coleoptile elongation in anoxic water and survival rate in flooded soil were significantly correlated (r = 0.879, P < 0.01). A significant QTL, likely to be a major gene (AG1), was found in chromosome segment substitution lines and in a backcrossed F2 population derived from tolerant and sensitive lines. Diverse rice genetic resources were classified into tolerant or sensitive accession groups reflecting their ecotypes. Our study revealed that anoxic water evaluation method saves space and time in a stable environment compared with flooded soil evaluation. It is applicable to QTL analysis and isolation of genes underlying anaerobic germination

    Organization of multisynaptic inputs to the dorsal and ventral dentate gyrus: retrograde trans-synaptic tracing with rabies virus vector in the rat

    Get PDF
    Behavioral, anatomical, and gene expression studies have shown functional dissociations between the dorsal and ventral hippocampus with regard to their involvement in spatial cognition, emotion, and stress. In this study we examined the difference of the multisynaptic inputs to the dorsal and ventral dentate gyrus (DG) in the rat by using retrograde trans-synaptic tracing of recombinant rabies virus vectors. Three days after the vectors were injected into the dorsal or ventral DG, monosynaptic neuronal labeling was present in the entorhinal cortex, medial septum, diagonal band, and supramammillary nucleus, each of which is known to project to the DG directly. As in previous tracing studies, topographical patterns related to the dorsal and ventral DG were seen in these regions. Five days after infection, more of the neurons in these regions were labeled and labeled neurons were also seen in cortical and subcortical regions, including the piriform and medial prefrontal cortices, the endopiriform nucleus, the claustrum, the cortical amygdala, the medial raphe nucleus, the medial habenular nucleus, the interpeduncular nucleus, and the lateral septum. As in the monosynaptically labeled regions, a topographical distribution of labeled neurons was evident in most of these disynaptically labeled regions. These data indicate that the cortical and subcortical inputs to the dorsal and ventral DG are conveyed through parallel disynaptic pathways. This second-order input difference in the dorsal and ventral DG is likely to contribute to the functional differentiation of the hippocampus along the dorsoventral axis.© 2013 Ohara et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Irregular atrial flutter following pulmonary vein isolation for persistent atrial fibrillation

    Get PDF
    AbstractA 65-year-old man with a history of refractory paroxysmal atrial fibrillation (AF) underwent catheter ablation for persistent AF lasting 2 months. AF was not terminated after complete isolation of the 4 pulmonary veins (PV). Instead, it was transformed to a sustained atrial tachyarrhythmia with beat-to-beat variability in the atrial cycle length. A 12-lead electrocardiogram during tachycardia showed negative flutter-like waves in the inferior leads. Entrainment pacing along the tricuspid annulus confirmed the diagnosis of irregular cavotricuspid isthmus (CTI)-dependent typical atrial flutter (AFL). Linear ablation of the CTI terminated AFL and restored sinus rhythm

    Dual Transneuronal Tracing in the Rat Entorhinal-Hippocampal Circuit by Intracerebral Injection of Recombinant Rabies Virus Vectors

    Get PDF
    Dual transneuronal tracing is a novel viral tracing methodology which employs two recombinant viruses, each expressing a different reporter protein. Peripheral injection of recombinant pseudorabies viruses has been used as a powerful method to define neurons that coordinate outputs to various peripheral targets of motor and autonomic systems. Here, we assessed the feasibility of recombinants of rabies virus (RV) vector for dual transneuronal tracing in the central nervous system. First, we examined whether two different RV-vectors can double label cells in vitro, and showed that efficient double labeling can be realized by infecting targeted cells with the two RV-vectors within a short time interval. The potential of dual transneuronal tracing was then examined in vivo in the entorhinal-hippocampal circuit, using the chain of projections from CA3 pyramidal cells to CA1 pyramidal cells and subsequently to entorhinal cortex. Six days after the injection of two RV-vectors into the left and right entorhinal cortex respectively, double-labeled neurons were observed in CA3 bilaterally. Some double-labeled neurons showed a Golgi-like labeling. Dual transneuronal tracing potentially provides a powerful and sensitive method to study issues such as the amount of convergence and divergence within and between circuits in the central nervous system. Using this sensitive technique, we established that single neurons in CA3 are connected to the entorhinal cortex bilaterally with only one synaptic relay

    Cardiomyocytes fuse with surrounding noncardiomyocytes and reenter the cell cycle

    Get PDF
    The concept of the plasticity or transdifferentiation of adult stem cells has been challenged by the phenomenon of cell fusion. In this work, we examined whether neonatal cardiomyocytes fuse with various somatic cells including endothelial cells, cardiac fibroblasts, bone marrow cells, and endothelial progenitor cells spontaneously in vitro. When cardiomyocytes were cocultured with endothelial cells or cardiac fibroblasts, they fused and showed phenotypes of cardiomyocytes. Furthermore, cardiomyocytes reentered the G2-M phase in the cell cycle after fusing with proliferative noncardiomyocytes. Transplanted endothelial cells or skeletal muscle–derived cells fused with adult cardiomyocytes in vivo. In the cryoinjured heart, there were Ki67-positive cells that expressed both cardiac and endothelial lineage marker proteins. These results suggest that cardiomyocytes fuse with other cells and enter the cell cycle by maintaining their phenotypes

    Typical atrial flutter with atypical flutter wave morphology due to abnormal interatrial conduction

    Get PDF
    We report a case of typical counterclockwise atrial flutter (AFL) with conduction block from right to left atrium along the coronary sinus (CS) musculature, confirmed by discontinuous CS activation sequence during pacing near the ostium and differential right atrial pacing. AFL was associated with an atypical flutter wave morphology, due to the detour of the activation wavefront from right to left atrium via alternate interatrial electrical connections, such as Bachmann&#8217;s bundle, the interatrial septum, or both. (Cardiol J 2011; 18, 4: 450&#8211;453

    Narrow-band imaging with magnifying endoscopy for Peyer's patches is useful in predicting the recurrence of remissive patients with ulcerative colitis

    Get PDF
    Background/AimsPeyer's patches (PPs) are aggregates of lymphoid follicles that are mainly located in the distal ileum; they play a major role in mucosal immunity. We recently reported that patients with ulcerative colitis (UC) have alterations in PPs that can be detected using narrow-band imaging with magnifying endoscopy (NBI-ME). However, the usefulness of NBI-ME in UC treatment as a whole is still unknown.MethodsWe collected NBI-ME images of PPs from 67 UC patients who had undergone ileocolonoscopy. We evaluated changes in the villi using the "villi index," which is based on three categories: irregular formation, hyperemia, and altered vascular network pattern. The patients were divided into two groups on the basis of villi index: low (L)- and high (H)-types. We then determined the correlation between morphological alteration of the PPs and various clinical characteristics. In 52 patients who were in clinical remission, we also analyzed the correlation between NBI-ME findings of PPs and clinical recurrence.ResultsThe time to clinical recurrence was significantly shorter in remissive UC patients with H-type PPs than in those with L-type PPs (P<0.01). Moreover, PP alterations were not correlated with age, sex, disease duration, clinical activity, endoscopic score, or extent of disease involvement. Multivariate analysis revealed that the existence of H-type PPs was an independent risk factor for clinical recurrence (hazard ratio, 3.3; P<0.01).ConclusionsUC patients with morphological alterations in PPs were at high risk of clinical relapse. Therefore, to predict the clinical course of UC, it may be useful to evaluate NBI-ME images of PPs
    corecore