Masanobu Kojo
Oita University
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Featured researches published by Masanobu Kojo.
Pediatric Infectious Disease Journal | 2007
Seigo Korematsu; Shin-ichi Uchiyama; Hiroaki Miyahara; Tomokazu Nagakura; Naho Okazaki; Tatsuya Kawano; Masanobu Kojo; Tatsuro Izumi
Background: The central nervous system (CNS) inflammation of Kawasaki disease (KD) has not been sufficiently evaluated in spite of the complications of irritability and CSF pleocytosis. Patients and Methods: Cerebrospinal fluid (CSF) and serum inflammatory cytokine values were simultaneously examined in 10 patients (2.6 ± 2.1 year of age) during the acute phase. They were all irritable and demonstrated mild consciousness disturbance. Results: The CSF IL6 was elevated (>3.0 pg/mL) in 6 patients, and 4 of them showed higher CSF than serum values. The CSF sTNFR1 was elevated (>0.5 μg/mL) in 6 patients, and 1 showed higher CSF than serum values. These CSF cytokine (IL6; 81.4 ± 192.8 pg/mL, sTNFR1; 1.1 ± 0.8 μg/mL) and CSF/serum ratio (IL6; 2.8 ± 5.2, sTNFR1 0.4 ± 0.4) in patients with KD were the same as those of patients with acute encephalitis/acute encephalopathy. Conclusions: The differences in the inflammatory cytokine value between CSF and serum suggest that the degree of systemic vasculitis is different between CSF and the circulating blood, and some patients with KD showed a higher degree of CSF inflammation.
Pediatric Neurology | 1996
Masanobu Kojo; Teruyuki Ogawa; Katsuhiko Yamada
We examined the developmental changes in carotid arterial blood flow in a group of neonates, infants, and children using a Doppler flowmeter. The mean, maximum and minimum carotid arterial blood flow (CABF) were measured serially in 35 healthy newborns during the first 5 days of life (total 175 records), and in 62 healthy children aged 1 month to 13 years. In newborns, the mean CABF increased significantly on the second day of life, while the maximum and minimum CABFs increased significantly every day during the first 3 days of life. The mean, maximum, and minimum CABFs increased steadily and significantly in those older than 1 month but reached a plateau after 2 to 4 years of age. Our results indicate that CABF changes with age in early life, reflecting a change in cardiac contraction and carotid-cerebral circulatory system. The measurement of CABF by Doppler flowmetry may be useful for examining cardiac and carotid-cerebral circulatory disorder.
Pediatric Neurology | 1998
Masanobu Kojo; Katsuhiko Yamada; Tatsuro Izumi
We examined the developmental changes in carotid arterial diameter and its change with pulsatile pressure in infants and children using the phase-locked echo-tracking method. The mean, maximum systolic, and minimum diastolic carotid arterial diameter and pulsating diameter changes were measured in 95 healthy children aged 1 month to 13 years. The mean, maximum, and minimum carotid arterial diameter increase significantly and exponentially with age, body weight, height, and body surface area, and the correlation coefficient was highest with body surface area. The change in carotid arterial diameter with pulse pressure increased gradually until 2 to 3 years of age. Our results suggest that the maturational changes in carotid diameter and the dynamic changes in the diameter reflect changes in the carotid-cerebral circulatory system. The noninvasive measurement of the carotid diameter and pulsating diameter changes by a phase-locked echo-tracking method is useful for examining carotid-cerebral circulatory disorders.
Brain & Development | 2006
Seigo Korematsu; Kazuhide Imai; Keisuke Sato; Tomoki Maeda; Souichi Suenobu; Masanobu Kojo; Tatsuro Izumi
We report two male siblings presenting with severe hypotonia, generalized muscle atrophy, multiple joint contractures and respiratory failure. The serum creatine kinase levels were within normal limits, 75 IU/l in the younger boy and 123 IU/l in the older one. Muscle biopsies at the age of 28 days in the younger boy and 48 days in the older one revealed dystrophic pathology with increased interstitial fibrous tissue, scattered basophilic fibers and an increased number of undeveloped type-2C fibers. Although the elder brother died from respiratory failure at 4 months of age, the younger child has been sustained with mechanical ventilation, and has been exhibiting non-progressive muscle symptoms. Upon re-biopsy of the younger sibling at the age of 3 years, neither basophilic regenerating fibers nor degenerating fibers were found. All muscle fibers were found to be extremely atrophic and behaved mostly like type-1 fibers, displaying the features of congenital neuromuscular disease with uniform type-1 fibers. Since early biopsies in congenital myopathies reveal numerous undifferentiated immature muscle fibers, it is difficult to make a definite diagnosis, unless we recognize disease-specific cytoplastic abnormalities of nemaline body formation and abnormalities of core structure.
Pediatrics International | 1995
Masanobu Kojo; Teruyuki Ogawa; Katsuhiko Yamada; Hirotomi Sonoda; Kiyoshi Saito
We analyzed the carotid artery blood flow waveform (CABFW) of an infant of a non‐insulin dependent diabetic mother with hypertrophic cardiomyopathy (IDM cardiomyopathy) through multivariate autoregressive analysis and compared the developmental change of his CABFW with that of normal newborns. The total power was lower than normal newborns on the second and third day of life when his heart dysfunction was severe, and elevated on the fifth day of life when normal‐heart function was recovered. The power of component 3 (C3), of which the damping frequency was 7–11 Hz, was slightly high on the second and third day of life and it decreased to the normal range on the fifth day of life by component analysis. In contrast, the power of C3 increased with decreasing resistance index of anterior cerebral artery (RI of ACA) which shows the cerebral vascular resistance of normal newborns.
Pediatrics International | 2005
Seigo Korematsu; Hiroaki Miyahara; Maki Takaji; Shin-ichi Uchiyama; Tomokazu Nagakura; So-ichi Suenobu; Masanobu Kojo; Tatsuro Izumi
Atopic myelitis, described by Kira et al . 1–3 in 1997, comprises atopic dermatitis, hyper-immunoglobulin (IgE)-emia and spinal involvement. The etiology, preventive methods and treatments were not established. Herein, we present a patient with severe atopic dermatitis, hyper-IgE-emia, Chiari malformation type I, and syringohydromyelia. Syringohydromyelia is sometimes complicated with Chiari malformation. However, the patient’s cerebrospinal fluid (CSF) soluble interleukin-2 receptor (sIL-2R) index increased. In our data and former reports, 4,5
Pediatrics International | 1995
Masanobu Kojo; Teruyuki Ogawa; Hirotomi Sonoda; Katsuhiko Yamada
The carotid artery blood flow waveform (CABFW) is regarded as a summation of cardiac impulse responses. These impulse responses are divided into several components through a two‐dimensional autoregressive modelling approach. Using this approach, we determined the developmental change in CABFW in 94 normal subjects from the neonatal period to adolescence. Our analysis demonstrated that: (i) the total power of impulse response increased significantly with increasing age. The component of impulse response was divided into six groups according to the damping frequency: group I (0 Hz), group II (1–5 Hz), group III (5–8 Hz), group IV (8–13 Hz), group V (13–17 Hz) and group VI (> 17 Hz); (ii) the power‐density and the damping time of group I and II impulse response increased significantly with increasing age; (iii) the power‐density and percent power of group III impulse response and power‐density of group IV impulse response increased significantly with increasing age. Our results indicated that CABFW contained some regular impulses and that group I, II, III and IV, which were influenced by several factors, including cardiac contraction and the compliance and frictional forces of the carotid artery, appeared to be important to the developmental change of CABFW in children.
Pediatrics International | 1999
Masanobu Kojo; Katsuhiko Yamada; Hiroshi Yamada; Miki Inutsuka; Yumi Hamada; Tatsuro Izumi; Teruyuki Ogawa
Abstract Background: The aim of the present study was to analyze the carotid artery blood flow waveform, using a two‐dimensional autoregressive modeling approach and component analysis, and to determine the relation between cardiac contractility, peripheral and cerebral circulation and characteristic values of component activities of carotid artery blood flow waveform in patients with atrial septal defect (ASD), with or without congestive heart failure.
Proceedings of the National Academy of Sciences of the United States of America | 2005
John P. Welsh; Hidetoshi Yamaguchi; Xiao Hui Zeng; Masanobu Kojo; Yasushi Nakada; Akiko Takagi; Mutsuyuki Sugimori; Rodolfo R. Llinás
Pediatric Neurology | 2006
Yumi Hamada; Hiroshi Yamada; Masanobu Kojo; Tatsuro Izumi