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Dive into the research topics where Yoshiro Nishikawa is active.

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Featured researches published by Yoshiro Nishikawa.


Neurology | 1986

Treatment of Kearns‐Sayre syndrome with coenzyme Q10

Saburo Ogasahara; Yoshiro Nishikawa; Shiro Yorifuji; Fumihisa Soga; Yusaku Nakamura; Mitsuo Takahashi; Shigeo Hashimoto; Norio Kono; Seiichiro Tarui

We studied the metabolism of coenzyme Q10 (CoQ) and the effects of CoQ therapy in five patients with Kearns-Sayre syndrome (KSS). Although the mitochondrial fraction was increased in muscles from KSS patients, CoQ content was slightly low. CoQ synthesis was normal in fibroblasts from KSS patients. Administration of 120 to 150 mg/d of CoQ improved abnormal metabolism of pyruvate and NADH oxidation in skeletal muscle. CoQ therapy decreased CSF protein concentration and CSF lactate/pyruvate ratio. ECG abnormalities and neurologic symptoms also improved.


Neurology | 1989

Long‐term coenzyme Q10 therapy for a mitochondrial encephalomyopathy with cytochrome c oxidase deficiency A 31P NMR study

Yoshiro Nishikawa; Mitsuo Takahashi; Shiro Yorifuji; Yusaku Nakamura; Satoshi Ueno; Seiichiro Tarui; T. Kozuka; T. Nishimura

For 2 years we administered high doses of coenzyme Q10 (CoQ) to a patient having mitochondrial encephalomyopathy with cytochrome c oxidase deficiency. Abnormal elevation of the serum lactate per pyruvate ratio and the increased concentration of serum lactate plus pyruvate induced by exercise decreased with CoQ treatment. This therapeutic effect continued for 2 years. 31P nuclear magnetic resonance spectroscopy showed acceleration of the postexercise recovery of the ratio of phosphocreatine to inorganic phosphate in muscle during CoQ treatment. These observations support the beneficial effect of CoQ on the impaired mitochondrial oxidative metabolism in muscle. Also, impaired central and peripheral nerve conductivities consistently improved during CoQ treatment. These results indicate that CoQ has clinical value in the long-term management of patients with mitochondrial encephalomyopathies, even though there are clinical limitations to the effects of this therapy.


Neurology | 1985

Improvement of abnormal pyruvate metabolism and cardiac conduction defect with coenzyme Ql0 in Kearns‐Sayre syndrome

Saburo Ogasahara; Shiro Yorifuji; Yoshiro Nishikawa; Mitsuo Takahashi; Keiji Wada; Takanori Hazama; Yusaku Nakamura; Shigeo Hashimoto; Norio Kono; Seiichiro Tarui

In a patient with Kearns-Sayre syndrome, concentration of coenzyme Ql0, a component of the mito-chondrial electron transport system, was decreased in serum and in the mitochondrial fraction of skeletal muscle. Serum concentrations of lactate and pyruvate were abnormally high, especially after exercise or oral glucose loading. Levels of folic acid in plasma and CSF were decreased. ECG showed a first-degree atrioventricular block. After administration of coenzyme Ql0 60 to 120 mg daily for 3 months, serum levels of lactate and pyruvate became normal, with improvement of atrioventricular block and ocular movements.


Journal of the Neurological Sciences | 1994

Involvement of the central nervous system in myotonic dystrophy

Kazuo Abe; Harutoshi Fujimura; Keiko Toyooka; Shiro Yorifuji; Yoshiro Nishikawa; Takanori Hazama; Takehiko Yanagihara

To investigate the etiological factors responsible for intellectual impairment and mood changes in patients with myotonic dystrophy (DM), we evaluated 14 patients with DM by means of neuropsychological evaluation and magnetic resonance images (MRI). There were significant differences between patients and controls in regard to the Barthel index, Zungs depression scale, attention, verbal fluency and digit span. All patients had ventricular enlargement and white matter abnormalities on MRI. However, the severity was variable and there was no difference in neuropsychological testing between patients with mild ventricular dilatation and those with severe dilatation. On the other hand, significant differences were present between patients with mild white matter lesions and those with severe white matter abnormalities in regard to verbal fluency and attention. Neuropathologic examination of an autopsied brain showed an increase in the interfascicular space of the white matter which produced pallor on myelin staining. The present findings suggested that the white matter abnormalities were the cause of cognitive impairment among patients with DM.


Journal of the Neurological Sciences | 1984

Dopamine metabolism in the central nervous system after discontinuation of l-dopa therapy in patients with Parkinson disease

Saburo Ogasahara; Yoshiro Nishikawa; Mitsuo Takahashi; Keiji Wada; Yusaku Nakamura; Shiro Yorifuji; Seiichiro Tarui

The dopamine turnover rate in the central nervous system (CNS) of parkinsonian patients was studied by means of the intravenous probenecid test during drug holiday (DH) and alternate day L-dopa therapy (ADDT). After L-dopa therapy was stopped, the dopamine turnover rate decreased more rapidly in patients with the marked wearing-off phenomenon than that in patients without fluctuation of symptoms. The lumbar CSF concentrations of L-dopa and 3-O-methyldopa of patients with and without wearing-off phenomenon were similar during L-dopa therapy. DH improved the effect of L-dopa on parkinsonian symptoms; it did not affect, however, the metabolism of exogenous L-dopa. The dopamine turnover rate in the CNS before L-dopa therapy or on on-days did not differ between patients tolerating and those not tolerating ADDT. However, it was significantly lower on off-days in patients not tolerating ADDT than in those tolerating ADDT. The relationship between dopamine storage in the CNS and the response to L-dopa therapy is discussed.


European Neurology | 1988

Mitochondrial Encephalomyopathy with Sleep Apnea

Chikao Tatsumi; Mitsuo Takahashi; Shiro Yorifuji; Yoshiro Nishikawa; Masataka Kitaguchi; Shigeo Hashimoto; Seiichiro Tarui

A rare case with mitochondrial encephalomyopathy, in association with cerebellar ataxia, peripheral neuropathy, mental retardation and alveolar hypoventilation syndrome with sleep apnea, as demonstrated by polysomnography, was encountered. This combination has not been described previously. From a prognostic point of view, alveolar hypoventilation syndrome with sleep apnea is an important clinical feature is this disease entity. Neither ataxia nor the abnormality of pyruvate metabolism was alleviated after 6 months of therapy with coenzyme Q10.


Neuroradiology | 1993

Reduced isotope uptake restricted to the motor area in patients with amyotrophic lateral sclerosis

Kazuo Abe; Shiro Yorifuji; Yoshiro Nishikawa

To study degeneration in the central nervous system in amyotrophic lateral sclerosis (ALS), we studied four patients using single photon emission tomography (SPECT) and magnetic resonance imaging (MRI). MRI demonstrated high intensity along the pyramidal tract on T2-weighted images in two. SPECT demonstrated reduced isotope uptake restricted to the motor area. While the cause of degeneration of the cortical neurons in the motor area is unknown, SPECT is useful for detecting the degeneration in patients with ALS.


Neuroradiology | 1992

Pure sensory stroke resulting from thalamic haemorrhage.

Kazuo Abe; Shiro Yorifuji; Yoshiro Nishikawa

SummaryPure sensory stroke has not previously been reported with thalamic haemorrhage and had indeed been considered to exclude cerebral haemorrhage. We describe a case of thalamic haemorrhage causing a pure sensory stroke and propose that we should tear in mind the possibility of haemorrhage in such cases.


Neuromuscular Disorders | 2012

Adult-onset multiple acyl CoA dehydrogenation deficiency associated with an abnormal isoenzyme pattern of serum lactate dehydrogenase.

Fuminobu Sugai; Kousuke Baba; Keiko Toyooka; Wen-Chen Liang; Ichizo Nishino; Hisae Sumi; Harutoshi Fujimura; Yoshiro Nishikawa

We report a case of a 37 year-old male with multiple acyl-CoA dehydrogenation deficiency (MADD). The patient had suffered from exercise intolerance in his hip and thigh muscles for one year. Then, restriction of carbohydrates for a diet made his symptoms rapidly deteriorate. Blood test revealed compound heterozygosity for two novel missense mutations in the electron transfer flavoprotein dehydrogenase gene (ETFDH), and an abnormal LDH isoenzyme pattern: LDH-1 (60.0%) and LDH-2 (26.0%) predominated with abnormally elevated LDH-1/LDH-2 ratio (2.3), compared with muscle-derived LDH-5 (4.0%). Oral riboflavin treatment significantly improved his exercise intolerance and the LDH profile: LDH-1 (34.4%), LDH-2 (34.9%), LDH-5 (6.9%) and LDH-1/LDH-2 ratio (1.0). The abnormal LDH isoenzyme pattern may be one feature of adult-onset MADD selectively affecting type I muscle fibers with relatively high LDH-1 content.


Journal of the Neurological Sciences | 1995

Clinical and magnetic resonance image correlation in idiopathic cerebellar ataxia

Kazuo Abe; Yoshiro Nishikawa; Harutoshi Fujimura; Keiko Toyooka; Misako Kaido; Shiro Yorifuji; Takehiko Yanagihara

Sixty-one patients who fulfilled the clinical criteria for idiopathic cerebellar ataxia and who had symptoms at least for 3 years were examined clinically and by magnetic resonance imaging (MRI). Based on the clinical signs, they were divided into patients with pure cerebellar signs (Group 1), patients with additional mild rigidity and/or hyperreflexia (Group 2) and patients with additional severe rigidity and hypokinesia (Group 3). Patients in Group 1 had milder disability and better prognosis than patients in Group 2 or Group 3 (ataxic score: 14.9 vs. 28.6 and 36.0; annual progression ratio: 0.26 vs. 0.65 and 0.70, respectively). We measured the area of the cerebellar vermis, ventral pons and dorsal brainstem on midsagittal T1-weighted MR images for all patients and age- and sex-matched controls. The cerebellar vermis as well as the ventral pons of patients were significantly smaller than corresponding structures in controls (p < 0.001). The ventral pons of patients in Group 2 and Group 3 was significantly smaller than that of patients in Group 1 (p < 0.0001, respectively), and the dorsal brainstem of patients in Group 2 and Group 3 was also significantly smaller than that of patients in Group 1 (p < 0.001, respectively). The ventral pons of patients in Group 3 was significantly smaller than that of patients in Group 2 (p < 0.05) as well. There was a significant correlation between the area of the ventral pons and the annual progression ratio (p < 0.001). With MRI, slight but definite hyperintensities were demonstrated in the pontine base and the medulla of 22 patients on proton density images. In the longitudinal study, patients in Group 2 and Group 3 had atrophy of the ventral pons already at an early stage. The ventral pons of patients in Group 3 was smaller at the initial MR examination than that of patients in Group 2. These observations suggest that patients with smaller ventral pons may have rapid progression and poor prognosis. Thus, even a relatively simple quantitation of the area of the ventral pons may be useful to predict the prognosis of patients, in addition to neurologic assessment at intervals.

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