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1.
Surg Open Sci ; 19: 87-94, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38601735

ABSTRACT

Background: Evidence regarding the application of the multispectral camera for blood flow measurement is insufficient, and its performance has not been compared with the conventional indocyanine green (ICG) method. Therefore, we retrospectively compared the effectiveness of a new multispectral camera for non-invasive, real-time, quantitative imaging of tissue oxygen (O2) saturation and hemoglobin (Hb) levels and commercially available ICG fluorescence imaging in hemodynamic assessment of gastric tubes in esophagectomy. Methods: Thirty patients who underwent thoracoscopic esophagectomy and gastric tube reconstruction for esophageal cancer were included in this study. The multispectral camera was used to measure tissue O2 saturation and Hb levels. The ICG fluorescence imaging, with the analysis software tool Lumi view, was employed to record ICG luminance changes, with values measured at the anastomotic site. Furthermore, the usefulness of each assessment device was examined using the arterial and venous blood flow indices as cutoff lines for cases with anastomotic failure. Results: In the evaluation of arterial perfusion, anastomotic leak occurred in three of the five (60 %) patients with arterial insufficiency as assessed by the ICG imaging, while anastomotic leakage occurred in all three patients (100 %) who were assessed as having arterial insufficiency by the multispectral camera. In the evaluation of venous perfusion, anastomotic leakage occurred in three of the nine (33.3 %) patients diagnosed with venous stasis by the IC imaging and in three of the five (60 %) patients assessed by the multispectral camera. Conclusion: The multispectral camera assessed gastric tube blood flow more accurately than the ICG fluorescence method.

2.
Cancer Diagn Progn ; 3(4): 498-503, 2023.
Article in English | MEDLINE | ID: mdl-37405219

ABSTRACT

BACKGROUND/AIM: Immune-checkpoint inhibitors have recently shown great promise in treating various cancers, but often cause immune-related adverse events (irAEs). Simultaneous drug-induced hypothyroidism and isolated adrenocorticotropic hormone (ACTH) deficiency are rare irAEs. This combination of irAEs is associated with paradoxical endocrine dysfunction characterized by large amounts of thyroid-stimulating hormone (TSH) and small amounts of ACTH in the anterior lobe of the pituitary. We herein report a case of hypothyroidism with isolated ACTH deficiency during pembrolizumab therapy for recurrent lung cancer. CASE REPORT: Our patient was a 66-year-old man with recurrence of squamous cell lung carcinoma. Four months after chemotherapy that included pembrolizumab, the patient presented with general fatigue and laboratory tests showed high concentrations of TSH with low concentrations of free-T4. He was diagnosed with hypothyroidism and levothyroxine was prescribed. His ACTH concentration was found to be low 1 week later when he developed an acute adrenal crisis with associated hyponatraemia. We then changed his diagnosis to concurrent hypothyroidism with isolated ACTH deficiency. His condition improved after 3 weeks of administration of cortisol. CONCLUSION: It is difficult to diagnose a concurrent paradoxical endocrine disorder, such as hypothyroidism with isolated ACTH deficiency, as in the present case. Physicians should pay attention to symptoms and laboratory data to identify various types of endocrine disorders as irAEs.

3.
Ann Surg Oncol ; 28(4): 2059-2067, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32661855

ABSTRACT

BACKGROUND: Several inflammation-based prognostic scores have a prognostic value in patients with various cancers. This study investigated the prognostic value of various inflammation-based prognostic scores in patients who underwent a surgery for adenocarcinoma of the esophagogastric junction (AEG) and upper gastric cancer (UGC). METHODS: We reviewed data of 206 patients who underwent surgery for AEG and UGC. We calculated neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), Glasgow Prognostic Score (GPS), modified GPS (mGPS), C-reactive protein (CRP)/albumin (Alb) ratio, prognostic index (PI), and prognostic nutritional index (PNI) and analyzed the relationship between these biomarkers and postoperative prognosis. RESULTS: In multivariate analyses for overall survival, mGPS (P = 0.0337, hazard ratio [HR] = 5.211), PI (P = 0.0002, HR = 21.20), and PNI (P < 0.0001, HR = 6.907) were identified as independent predictive factors. A multivariate analysis for recurrence-free survival showed that only PI (P = 0.0006, HR = 11.89) and PNI (P = 0.0002, HR = 4.972) were independent predictive factors among the above-mentioned inflammation-based prognostic scores. CONCLUSIONS: In various inflammation-based prognostic scores, PI and PNI were more strongly associated with poor prognosis in patients who underwent surgery for AEG and UGC.


Subject(s)
Adenocarcinoma , Stomach Neoplasms , Adenocarcinoma/surgery , Esophagogastric Junction/surgery , Humans , Inflammation , Prognosis , Retrospective Studies , Stomach Neoplasms/surgery
4.
Surg Case Rep ; 5(1): 72, 2019 May 03.
Article in English | MEDLINE | ID: mdl-31053962

ABSTRACT

BACKGROUND: Recurrences after radical esophagectomy are common. The prognosis for recurrent esophageal cancer is generally poor. Recurrences usually occur between 1 and 3 years of surgery, with the duration of median survival after recurrence ranging from 5 to 10 months. The number of sites and involved organs vary among patients. Consequently, a standard therapeutic strategy has not been established, and the role of surgery in the management of recurrence is unclear. CASE PRESENTATION: A 67-year-old man presented with dysphagia 6 months previously and was diagnosed with esophageal squamous cell carcinoma (ESCC) in the upper thoracic region (T2M0M0, stage IB), for which he underwent thoracoscopy-assisted esophagectomy and lymphadenectomy. Adjuvant chemotherapy was not prescribed. Three years after the operation, he developed a solitary metastasis in the left lung, requiring segmentectomy followed by chemotherapy with combined cisplatin (CDDP) and 5-fluorouracil (5-FU). The following year, a metastatic lesion was recognized in the right lung, invading the chest wall, for which he underwent partial lobectomy with local chest wall resection. Multiple mediastinal and abdominal lymph node (LN) metastases were detected in the right lung a year later, which necessitated chemoradiation to a dose of 50.4 Gy with concomitant CDDP and 5-FU. Post-treatment computed tomography (CT) showed a good response. Positron emission tomography (PET)-CT revealed a reduction in the metastatic LNs with no fluoro-deoxy-glucose (FDG) uptake. The following year, metastases were detected in the left cervical LNs. Owing to the limited extent of metastases, resection was followed by chemoradiation to a dose of 50 Gy with CDDP and 5-FU. The following year, metastases were detected in the mediastinal LNs; chemotherapy was administered with nedaplatin and docetaxel. The follow-up CT and PET-CT demonstrated complete disappearance of the tumor, and the patient is currently surviving without recurrence for 11 years from the first curative operation. CONCLUSIONS: This case demonstrates that aggressive multidisciplinary treatment including surgery and radiation to achieve local control could be a meaningful treatment strategy in cases with limited and slowly occurring recurrences.

5.
J Gastroenterol Hepatol ; 34(2): 355-363, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30119141

ABSTRACT

BACKGROUND AND AIM: The C-reactive protein (CRP)/albumin (Alb) ratio has been reported as a novel prognostic marker in several cancers. The objective of this study was to investigate the prognostic value of the CRP/Alb ratio in patients who underwent surgery for adenocarcinoma of the esophagogastric junction (AEG) and upper gastric cancer (UGC). METHODS: Data for 144 patients who underwent surgery for AEG and UGC were reviewed. The CRP/Alb ratio, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, Glasgow Prognostic Score, and controlling nutritional status score were calculated, and the relationship between these biomarkers and postoperative prognosis was analyzed. RESULTS: The optimal cutoff value of the CRP/Alb ratio was determined to be 0.1. According to the cutoff value of CRP/Alb ratio, patients were divided into two groups (CRP/Alb < 0.1, n = 124; CRP/Alb ≥ 0.1, n = 20). The 5-year recurrence-free survival and overall survival (OS) rates were significantly lower in the patients with the CRP/Alb ratio ≥ 0.1 than in those with the CRP/Alb ratio < 0.1 (recurrence-free survival: 44.9% vs 77.9%, P = 0.0011; OS: 43.4% vs 82.0%, P < 0.0001). In the multivariate analyses, the N-stage, and CRP/Alb ratio ≥ 0.1 were identified as independent predictive factors for OS in patients with AEG and UGC (P = 0.0061 and P = 0.0439, respectively). CONCLUSIONS: The CRP/Alb ratio was strongly associated with poor prognosis in patients who underwent surgery for AEG and UGC.


Subject(s)
Adenocarcinoma/blood , Biomarkers, Tumor/blood , C-Reactive Protein/analysis , Esophageal Neoplasms/blood , Esophagogastric Junction , Serum Albumin, Human/analysis , Stomach Neoplasms/blood , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Adult , Aged , Aged, 80 and over , Esophageal Neoplasms/mortality , Esophageal Neoplasms/pathology , Esophageal Neoplasms/surgery , Esophagogastric Junction/pathology , Esophagogastric Junction/surgery , Female , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Predictive Value of Tests , Progression-Free Survival , Retrospective Studies , Stomach Neoplasms/mortality , Stomach Neoplasms/pathology , Stomach Neoplasms/surgery , Time Factors
6.
Anticancer Res ; 38(4): 2335-2338, 2018 04.
Article in English | MEDLINE | ID: mdl-29599357

ABSTRACT

"Crawling type" gastric cancer (GC) is known as a rare variant of early GCs, which is difficult to diagnose at an early stage because of low-grade nuclear atypia and a morphology mimicking intestinal metaplasia. This is a case report of a 69-year-old woman who was diagnosed with early-stage gastric cancer. She had endoscopic submucosal resection (ESD) and histologically, both horizontal and vertical margins were negative. Seven months after ESD, a new lesion of the stomach was detected by follow-up gastroscopy. Laparoscopic distal gastrectomy was performed and "crawling type" glands were observed throughout the whole area of the tumor. We should keep this variant in mind, especially when a tumor is superficial depressed or superficial flat type in the middle of the stomach. Careful observation with multiple biopsies of all mucosal layer and a re-biopsy is the key procedure for obtaining the right diagnosis. Endoscopic and histological characteristics should also be reviewed.


Subject(s)
Adenocarcinoma/diagnosis , Adenocarcinoma/surgery , Endoscopic Mucosal Resection , Margins of Excision , Stomach Neoplasms/diagnosis , Stomach Neoplasms/surgery , Adenocarcinoma/pathology , Aged , Female , Gastrectomy , Gastric Mucosa/pathology , Gastric Mucosa/surgery , Gastroscopy , Humans , Neoplasm Invasiveness , Stomach Neoplasms/pathology
7.
PLoS One ; 11(12): e0168588, 2016.
Article in English | MEDLINE | ID: mdl-27992543

ABSTRACT

PURPOSE: Quantitative imaging of neuromagnetic fields based on automated region of interest (ROI) setting was analyzed to determine the characteristics of cerebral neural activity in ischemic areas. METHODS: Magnetoencephalography (MEG) was used to evaluate spontaneous neuromagnetic fields in the ischemic areas of 37 patients with unilateral internal carotid artery (ICA) occlusive disease. Voxel-based time-averaged intensity of slow waves was obtained in two frequency bands (0.3-4 Hz and 4-8 Hz) using standardized low-resolution brain electromagnetic tomography (sLORETA) modified for a quantifiable method (sLORETA-qm). ROIs were automatically applied to the anterior cerebral artery (ACA), anterior middle cerebral artery (MCAa), posterior middle cerebral artery (MCAp), and posterior cerebral artery (PCA) using statistical parametric mapping (SPM). Positron emission tomography with 15O-gas inhalation (15O-PET) was also performed to evaluate cerebral blood flow (CBF) and oxygen extraction fraction (OEF). Statistical analyses were performed using laterality index of MEG and 15O-PET in each ROI with respect to distribution and intensity. RESULTS: MEG revealed statistically significant laterality in affected MCA regions, including 4-8 Hz waves in MCAa, and 0.3-4 Hz and 4-8 Hz waves in MCAp (95% confidence interval: 0.020-0.190, 0.030-0.207, and 0.034-0.213), respectively. We found that 0.3-4 Hz waves in MCAp were highly correlated with CBF in MCAa and MCAp (r = 0.74, r = 0.68, respectively), whereas 4-8 Hz waves were moderately correlated with CBF in both the MCAa and MCAp (r = 0.60, r = 0.63, respectively). We also found that 4-8 Hz waves in MCAp were statistically significant for misery perfusion identified on 15O-PET (p<0.05). CONCLUSIONS: Quantitatively imaged spontaneous neuromagnetic fields using the automated ROI setting enabled clear depiction of cerebral ischemic areas. Frequency analysis may reveal unique neural activity that is distributed in the impaired vascular metabolic territory, in which the cerebral infarction has not yet been completed.


Subject(s)
Brain Ischemia/diagnosis , Carotid Artery Diseases/diagnosis , Carotid Artery, Internal/diagnostic imaging , Magnetoencephalography/methods , Adult , Aged , Aged, 80 and over , Brain Mapping , Cerebrovascular Circulation , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Positron-Emission Tomography
8.
Neuroimage Clin ; 2: 394-401, 2013.
Article in English | MEDLINE | ID: mdl-24179793

ABSTRACT

Autism spectrum disorder (ASD) is often described as a disorder of aberrant neural connectivity and/or aberrant hemispheric lateralization. Although it is important to study the pathophysiology of the developing ASD cortex, the physiological connectivity of the brain in young children with ASD under conscious conditions has not yet been described. Magnetoencephalography (MEG) is a noninvasive brain imaging technique that is practical for use in young children. MEG produces a reference-free signal and is, therefore, an ideal tool for computing the coherence between two distant cortical rhythms. Using a custom child-sized MEG, we recently reported that 5- to 7-year-old children with ASD (n = 26) have inherently different neural pathways than typically developing (TD) children that contribute to their relatively preserved performance of visual tasks. In this study, we performed non-invasive measurements of the brain activity of 70 young children (3-7 years old, of which 18 were aged 3-4 years), a sample consisting of 35 ASD children and 35 TD children. Physiological connectivity and the laterality of physiological connectivity were assessed using intrahemispheric coherence for 9 frequency bands. As a result, significant rightward connectivity between the parietotemporal areas, via gamma band oscillations, was found in the ASD group. As we obtained the non-invasive measurements using a custom child-sized MEG, this is the first study to demonstrate a rightward-lateralized neurophysiological network in conscious young children (including children aged 3-4 years) with ASD.

9.
Mol Autism ; 4(1): 38, 2013 Oct 08.
Article in English | MEDLINE | ID: mdl-24103585

ABSTRACT

BACKGROUND: Magnetoencephalography (MEG) is used to measure the auditory evoked magnetic field (AEF), which reflects language-related performance. In young children, however, the simultaneous quantification of the bilateral auditory-evoked response during binaural hearing is difficult using conventional adult-sized MEG systems. Recently, a child-customised MEG device has facilitated the acquisition of bi-hemispheric recordings, even in young children. Using the child-customised MEG device, we previously reported that language-related performance was reflected in the strength of the early component (P50m) of the auditory evoked magnetic field (AEF) in typically developing (TD) young children (2 to 5 years old) [Eur J Neurosci 2012, 35:644-650]. The aim of this study was to investigate how this neurophysiological index in each hemisphere is correlated with language performance in autism spectrum disorder (ASD) and TD children. METHODS: We used magnetoencephalography (MEG) to measure the auditory evoked magnetic field (AEF), which reflects language-related performance. We investigated the P50m that is evoked by voice stimuli (/ne/) bilaterally in 33 young children (3 to 7 years old) with ASD and in 30 young children who were typically developing (TD). The children were matched according to their age (in months) and gender. Most of the children with ASD were high-functioning subjects. RESULTS: The results showed that the children with ASD exhibited significantly less leftward lateralisation in their P50m intensity compared with the TD children. Furthermore, the results of a multiple regression analysis indicated that a shorter P50m latency in both hemispheres was specifically correlated with higher language-related performance in the TD children, whereas this latency was not correlated with non-verbal cognitive performance or chronological age. The children with ASD did not show any correlation between P50m latency and language-related performance; instead, increasing chronological age was a significant predictor of shorter P50m latency in the right hemisphere. CONCLUSIONS: Using a child-customised MEG device, we studied the P50m component that was evoked through binaural human voice stimuli in young ASD and TD children to examine differences in auditory cortex function that are associated with language development. Our results suggest that there is atypical brain function in the auditory cortex in young children with ASD, regardless of language development.

10.
Sci Rep ; 3: 1139, 2013.
Article in English | MEDLINE | ID: mdl-23355952

ABSTRACT

A subset of individuals with autism spectrum disorder (ASD) performs more proficiently on certain visual tasks than may be predicted by their general cognitive performances. However, in younger children with ASD (aged 5 to 7), preserved ability in these tasks and the neurophysiological correlates of their ability are not well documented. In the present study, we used a custom child-sized magnetoencephalography system and demonstrated that preserved ability in the visual reasoning task was associated with rightward lateralisation of the neurophysiological connectivity between the parietal and temporal regions in children with ASD. In addition, we demonstrated that higher reading/decoding ability was also associated with the same lateralisation in children with ASD. These neurophysiological correlates of visual tasks are considerably different from those that are observed in typically developing children. These findings indicate that children with ASD have inherently different neural pathways that contribute to their relatively preserved ability in visual tasks.


Subject(s)
Autistic Disorder/physiopathology , Brain/physiology , Autistic Disorder/psychology , Brain Mapping , Child , Child, Preschool , Female , Humans , Magnetoencephalography , Male , Reading , Task Performance and Analysis
11.
Sci Rep ; 2: 384, 2012.
Article in English | MEDLINE | ID: mdl-22540030

ABSTRACT

In humans, oxytocin (OT) enhances prosocial behaviour. However, it is still unclear how the prosocial effects of OT are modulated by emotional features and/or individuals' characteristics. In a placebo-controlled design, we tested 20 healthy male volunteers to investigate these behavioural and neurophysiological modulations using magnetoencephalography. As an index of the individuals' characteristics, we used the empathy quotient (EQ), the autism spectrum quotient (AQ), and the systemising quotient (SQ). Only during the perception of another person's angry face was a higher SQ a significant predictor of OT-induced prosocial change, both in the behavioural and neurophysiological indicators. In addition, a lower EQ was only a significant predictor of OT-induced prosocial changes in the neurophysiological indicators during the perception of angry faces. Both on the behavioural and the neurophysiological level, the effects of OT were specific for anger and correlated with a higher SQ.

12.
Neurosci Lett ; 515(2): 141-6, 2012 May 02.
Article in English | MEDLINE | ID: mdl-22465137

ABSTRACT

Accurate perception of fundamental frequency (F0) contour changes in the human voice is important for understanding a speaker's intonation, and consequently also his/her attitude. In this study, we investigated the neural processes involved in the perception of F0 contour changes in the Japanese one-syllable interjection "ne" in 21 native-Japanese listeners. A passive oddball paradigm was applied in which "ne" with a high falling F0 contour, used when urging a reaction from the listener, was randomly presented as a rare deviant among a frequent "ne" syllable with a flat F0 contour (i.e., meaningless intonation). We applied an adaptive spatial filtering method to the neuromagnetic time course recorded by whole-head magnetoencephalography (MEG) and estimated the spatiotemporal frequency dynamics of event-related cerebral oscillatory changes in the oddball paradigm. Our results demonstrated a significant elevation of beta band event-related desynchronization (ERD) in the right temporal and frontal areas, in time windows from 100 to 300 and from 300 to 500 ms after the onset of deviant stimuli (high falling F0 contour). This is the first study to reveal detailed spatiotemporal frequency characteristics of cerebral oscillations during the perception of intonational (not lexical) F0 contour changes in the human voice. The results further confirmed that the right hemisphere is associated with perception of intonational F0 contour information in the human voice, especially in early time windows.


Subject(s)
Cerebral Cortex/physiology , Speech Perception/physiology , Acoustic Stimulation , Adult , Female , Humans , Magnetoencephalography , Male , Voice
13.
Eur J Neurosci ; 35(4): 644-50, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22321133

ABSTRACT

Language development progresses at a dramatic rate in preschool children. As rapid temporal processing of speech signals is important in daily colloquial environments, we performed magnetoencephalography (MEG) to investigate the linkage between speech-evoked responses during rapid-rate stimulus presentation (interstimulus interval < 1 s) and language performance in 2- to 5-year-old children (n = 59). Our results indicated that syllables with this short stimulus interval evoked detectable P50m, but not N100m, in most participants, indicating a marked influence of longer neuronal refractory period for stimulation. The results of equivalent dipole estimation showed that the intensity of the P50m component in the left hemisphere was positively correlated with language performance (conceptual inference ability). The observed positive correlations were suggested to reflect the maturation of synaptic organisation or axonal maturation and myelination underlying the acquisition of linguistic abilities. The present study is among the first to use MEG to study brain maturation pertaining to language abilities in preschool children.


Subject(s)
Auditory Cortex/physiology , Brain Mapping , Evoked Potentials, Auditory/physiology , Language Development , Language , Acoustic Stimulation , Child, Preschool , Cognition/physiology , Electroencephalography , Female , Functional Laterality , Humans , Magnetoencephalography , Male , Neuropsychological Tests , Reaction Time , Regression Analysis
14.
J Neurosci ; 31(42): 14984-8, 2011 Oct 19.
Article in English | MEDLINE | ID: mdl-22016531

ABSTRACT

Recent neuroimaging studies support the view that a left-lateralized brain network is crucial for language development in children. However, no previous studies have demonstrated a clear link between lateralized brain functional network and language performance in preschool children. Magnetoencephalography (MEG) is a noninvasive brain imaging technique and is a practical neuroimaging method for use in young children. MEG produces a reference-free signal, and is therefore an ideal tool to compute coherence between two distant cortical rhythms. In the present study, using a custom child-sized MEG system, we investigated brain networks while 78 right-handed preschool human children (32-64 months; 96% were 3-4 years old) listened to stories with moving images. The results indicated that left dominance of parietotemporal coherence in theta band activity (6-8 Hz) was specifically correlated with higher performance of language-related tasks, whereas this laterality was not correlated with nonverbal cognitive performance, chronological age, or head circumference. Power analyses did not reveal any specific frequencies that contributed to higher language performance. Our results suggest that it is not the left dominance in theta oscillation per se, but the left-dominant phase-locked connectivity via theta oscillation that contributes to the development of language ability in young children.


Subject(s)
Brain Mapping , Brain/physiology , Functional Laterality/physiology , Language , Theta Rhythm/physiology , Child, Preschool , Female , Humans , Magnetoencephalography , Male , Statistics as Topic
15.
Neuroreport ; 21(17): 1106-10, 2010 Dec 08.
Article in English | MEDLINE | ID: mdl-21475088

ABSTRACT

Oscillations in the higher frequency range are closely related to regional brain hemodynamic changes. Here we investigated this neurovascular coupling in humans in response to electrical stimulation of the right median nerve. In a single-trial study, we simultaneously recorded hemodynamic fluctuations in the somatosensory cortex by near infrared spectroscopy and brain neuronal oscillations by whole-head magnetoencephalography (MEG). The results from six volunteers showed that neural fluctuations at ß or γ-band power were correlated with hemodynamic fluctuation during stimulus conditions. These correlations were prominent with a time delay of 5-7 s. This study provides new direct evidence that hemodynamic onset lags specific neural oscillations in the order of seconds in human awake conditions using noninvasive methods.


Subject(s)
Neural Pathways/physiology , Somatosensory Cortex/physiology , Adult , Beta Rhythm/physiology , Cerebrovascular Circulation/physiology , Data Interpretation, Statistical , Electric Stimulation , Electroencephalography , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging , Magnetoencephalography , Male , Median Nerve/physiology , Oxyhemoglobins/metabolism , Somatosensory Cortex/blood supply , Spectroscopy, Near-Infrared
16.
J Gen Virol ; 90(Pt 4): 827-832, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19264633

ABSTRACT

The Japanese encephalitis virus (JEV) circulating in Japan consists of viruses with multiple phylogenetic origins. Phylogenetic analysis revealed that some JEV strains have recently migrated from south-east and continental east Asian countries. One phylogenetic subcluster of the JEV strains circulating in Japan was closely related to viruses isolated in Vietnam and China's inland region while other JEV subclusters were related to viruses isolated in Shanghai, China. One virus subcluster, however, was isolated solely in Japan and was not found in any other Asian country. Therefore, our data suggests that the JEVs that have remained or are circulating in Japan include a mixture of viruses that have previously migrated from south-east and continental east Asian countries.


Subject(s)
Culicidae/virology , Encephalitis Virus, Japanese , Encephalitis, Japanese , Insect Vectors/virology , Phylogeny , Animals , Asia, Southeastern/epidemiology , Cells, Cultured , Culicidae/physiology , Ecology , Encephalitis Virus, Japanese/classification , Encephalitis Virus, Japanese/genetics , Encephalitis Virus, Japanese/isolation & purification , Encephalitis Virus, Japanese/physiology , Encephalitis, Japanese/epidemiology , Encephalitis, Japanese/virology , Asia, Eastern/epidemiology , Genotype , Humans , Insect Vectors/physiology , Japan/epidemiology , Polymerase Chain Reaction , Sequence Analysis, DNA
17.
Jpn J Ophthalmol ; 48(2): 115-22, 2004.
Article in English | MEDLINE | ID: mdl-15064972

ABSTRACT

PURPOSE: To establish an objective visual field analysis by visual evoked magnetic fields. METHODS: Forty-eight focal areas of the visual field were stimulated by the visual evoked response imaging system (VERIS). The multifocal visual evoked magnetic fields (mfVEFs) of 11 healthy subjects were recorded. The output signals were recorded with VERIS, and the second-order kernel was calculated. The equivalent current dipoles (ECDs) were estimated, and the relative positioning of ECDs was determined by a magnetoencephalography (MEG) system. RESULTS: The mfVEFs consisted of either two- or three-peak waves. Large amplitude mfVEFs were elicited when the stimulus was confined to 6 degrees of the central visual field, but a strong response could not always be obtained between 6 degrees and 12 degrees. All ECDs were estimated to originate in the occipital striate cortex. The ECDs for the upper (lower) field stimulations were estimated to be on the lower (upper) cortex, while those for right (left) field stimulations were on the left (right) cortex. CONCLUSIONS: The locations of mfVEF peak ECDs were correlated with the stimulated visual field and generally matched the cruciform model. In combination with the multifocal technique, MEG can be used for objective visual field analysis.


Subject(s)
Evoked Potentials, Visual/physiology , Magnetoencephalography/methods , Visual Fields/physiology , Adult , Humans , Male , Pattern Recognition, Visual
18.
Vision Res ; 44(10): 1033-8, 2004 May.
Article in English | MEDLINE | ID: mdl-15031097

ABSTRACT

In humans with albinism, a large percentage of the ganglion cell axons from the temporal retina decussate abnormally in the chiasm and synapse in the contralateral LGN. The aim of this study was to determine whether the misrouting of the optic fibers can be detected by magnetoencephalography (MEG). Visually evoked magnetic fields (VEFs) were recorded from three patients with albinism. After monocular stimulation, the isofield contour maps of the VEFs showed a single current dipole pattern over the contralateral hemisphere in patients with albinism. These results clearly illustrated the reduced uncrossed retinofugal pathway of patients with albinism.


Subject(s)
Albinism/pathology , Magnetoencephalography/methods , Retinal Ganglion Cells/pathology , Adolescent , Adult , Albinism/physiopathology , Albinism, Ocular/pathology , Albinism, Ocular/physiopathology , Axons/pathology , Child , Evoked Potentials, Visual/physiology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Optic Nerve/physiopathology , Photic Stimulation/methods , Retinal Ganglion Cells/physiology , Visual Pathways/pathology , Visual Pathways/physiopathology
19.
Clin Neurophysiol ; 115(2): 435-47, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14744586

ABSTRACT

OBJECTIVE: The digit representations in area 3b were studied to examine whether there is training-dependent reorganization in string players. METHODS: Somatosensory evoked magnetic fields were recorded following electrical stimulation of digits 1 (D1), 2 (D2) and 5 (D5) of both hands in 8 string players and of the left hand in 12 control subjects. The N20m and P30m responses, and high-frequency oscillations (HFOs) were separated by 3-300 Hz and 300-900 Hz bandpass filtering. RESULTS: The dipole locations on the coronal plane and strengths of D1, D2 and D5, and D1-D5 cortical distance estimated at the peak of N20m or P30m did not differ between left and right hand in string players or between left hand in string players and controls. On the other hand, the dipole locations of D2 estimated from N20m and P30m and of D1 from N20m were significantly anterior, the D2-D5 distance from P30m longer, and the number of HFO peaks larger for D5 in string players than controls. CONCLUSIONS/SIGNIFICANCE: With strong mutual competition among the fingering digits, the scale of reorganization should be much smaller as compared with the competition-free denervation-induced reorganizations. Taken together, the training-dependent reorganization of somatosensory cortex in string players is manifest not only in the enlarged cortical representation but also in the enhanced HFOs presumably representing activity of the fast-spiking interneurons.


Subject(s)
Brain Mapping , Evoked Potentials, Somatosensory/physiology , Practice, Psychological , Somatosensory Cortex/physiology , Adolescent , Adult , Analysis of Variance , Electric Stimulation , Electroencephalography , Female , Fingers/innervation , Fingers/physiology , Functional Laterality/physiology , Hand/innervation , Hand/physiology , Humans , Magnetic Resonance Imaging , Magnetoencephalography , Male , Music , Physical Stimulation , Professional Practice , Reaction Time/physiology , Sensory Thresholds/physiology , Statistics, Nonparametric
20.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 4465-8, 2004.
Article in English | MEDLINE | ID: mdl-17271297

ABSTRACT

We examined the periodic synchronous characteristic response to photic stimulation in schizophrenia using electroencephalography (EEG) and magnetoencephalography (MEG). We tested whether neural synchronization deficits were present in subjects with schizophrenia using photic stimulation to evaluate the frequency entrainment in 18 normal subjects and 19 schizophrenia patients. A conventional vertical-type 160-channel MEG (PQ1160C, Yokogawa Electric Corporation) was used. Photic stimulation was at frequencies from 8 to 10.5 Hz at intervals of 0.5 Hz. There were ten stimuli at each frequency, and each lasted 10 seconds. The power spectrum at each site was based on the international 10/20 derivation. The power spectrum in schizophrenia patients was smaller than that in normal subjects at each site. A gender difference was observed in normal subjects, but not in schizophrenia patients. MEG, like EEG, is an effective method for research on neuropathy of the psyche.

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