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J Ono

Publications and source records attributed to J Ono.

At least 19 recordsLinked to original sources

Proton magnetic resonance spectroscopy of Sjögren-Larsson syndrome heterozygotes.

A deficit of fatty alcohol:NAD+ oxidoreductase complex (FAO) activity has been detected in patients with the Sjögren-Larsson syndrome (SLS). A moderate decrease in FAO activity has also been reported in heterozygote SLS subjects. Abnormal peaks were detected with proton magnetic resonance spectroscopy (1H-MRS) in homozygote SLS subjects. The purpose of this study was to examine whether 1H-MRS can be used to detect metabolic and/or pathological abnormalities in heterozygote SLS subjects. Four SLS heterozygotes were examined using 1H-MRS. A moderate decrease in FAO activity was demonstrated in two of the four heterozygotes. Abnormal peaks were detected at 0.9 ppm in the spectrum from cerebral hemispheres of every heterozygote. 1H-MRS was able to detect an abnormal accumulation of fatty alcohols and lipids, which is expected to increase due to an decrease in FAO activity or dysmyelination in heterozygote SLS subjects. Thus, 1H-MRS is suggested to be a powerful tool in the screening of SLS heterozygotes.

Adult↗

Influences of venous involvement on postoperative brain damage following the anterior interhemispheric approach.

BACKGROUND: The anterior interhemispheric approach offers us an excellent surgical view for suprasellar lesions. Following this approach, we occasionally encounter postoperative brain damage in the frontal lobes. To assess the determinants of such a complication, we undertook a clinical study. METHOD: Potential causes for such brain damage were evaluated in 28 consecutive patients with suprasellar tumours extirpated using this approach. We focused particularly on the influences of venous involvement during surgery. The draining territory index (DTI) was originally devised for estimating the extent of the draining area of the sacrificed bridging veins. FINDINGS: CT evident brain damage was observed in five of 28 patients (17.8%), but only one patient (3.6%) showed clinically significant postoperative deficits. The patient's age, tumour pathology, tumour character, tumour size, duration of surgery, and radicality of the surgery did not affect the incidence of the brain damage. Of the twelve patients whose bridging veins were sacrificed during surgery, four (33.3%) showed brain damage in the frontal lobes. In contrast, such damage was observed in only one patient out of 16 (6.3%) whose bridging veins were preserved. Among the brain-damaged group, the average DTI of the sacrificed veins was significantly higher than that among the non-brain-damaged group. INTERPRETATION: Venous involvement during surgery significantly aggravated postoperative brain damage following the anterior interhemispheric approach. The DTI was useful in predicting the risk of brain damage, and a large bridging vein with a DTI over 50% should not be sacrificed during surgery.

Adult↗

Mutational analysis of MECP2 in Japanese patients with atypical Rett syndrome.

Rett syndrome (RTT) is one of the most common neurodevelopmental disorders in females. Recently, this disease was found to be linked with mutations in the methyl-CpG-binding protein 2 gene (MECP2) and various mutations have been reported. To explore the spectrum of phenotypes resulting from MECP2 mutations, we searched for mutations in the MECP2 of 20 Japanese patients who had more than five of the criteria necessary for RTT diagnosis proposed in 1988 (The Rett Syndrome Diagnostic Criteria Work Group, Ann Neurol 23 (1988) 425) and compared the phenotype between patients with and without mutation by giving a score to each diagnostic criterion. We found four missense mutations (T158M, R133C, Y120D, and R306C), two nonsense mutations (R168X and R270X), one frameshift (726delAAAG) mutation, and one polymorphism (A201V) in ten patients (50%). This included two novel mutations (726delAAAG and Y120D). All mutations were found in the highly conserved methyl-binding and transcription repression domains. Comparison of the mean total diagnostic criterion score of the groups with and without mutation did not reveal any statistically significantly difference (P=0.28). The only difference between the groups, which was of borderline significance (P=0.051), was the sum of the scores for diagnostic criteria 2 (apparently normal psychomotor development through the first 6 months) and 5 (loss of acquired purposeful hand skills between the ages of 6 and 30 months). From these results, it is suggested that the clinical phenotype of RTT is variable and it is important to investigate the MECP2 genotype for patients having more than five criteria and not only in those who exhibit all RTT diagnostic criteria. The diagnosis of RTT is clinically difficult before 3 years of age, especially in atypical cases, but molecular analysis of the MECP2 will assist diagnosis in some patients.

Adolescent↗

Outcome prediction in severe head injury: analyses of clinical prognostic factors.

Retrospective analysis of 272 patients with severe head injury was performed. Patient age, Glasgow Coma Scale (GCS) score, pupillary abnormalities, impaired oculocephalic response, presence of subarachnoid haemorrhage, and multiplicity of parenchymal lesions on computerised tomography (CT) were examined. The CT findings were divided into 2 groups, diffuse brain injury (DBI) and mass lesion, according to the classification of the Traumatic Coma Data Bank. The DBI, basically, has no high or mixed density lesion more than 25 ml on CT, and was classified into 4 subgroups: DBI I includes injuries where there is no visible pathology; DBI II includes all injuries in which the cisterns are present with a midline shift of less than 5 mm; DBI III includes injuries with swelling where the cisterns are compressed or absent and the midline shift is less than 5 mm; DBI IV includes injuries with a midline shift of more than 5 mm. The mass lesions were categorised into 3 subgroups: epidural haematoma; acute subdural haematoma; and intracerebral haematoma. Outcomes were determined at 6 months following trauma using the Glasgow Outcome Scale. All DBI I patients recovered well. In the DBI II group, age, GCS score and detection of multiple parenchymal lesions on CT were significantly correlated with outcome. For the DBI III and IV groups, the only significant prognostic factor was the GCS score. In patients with a mass lesion, the GCS score was the only significant prognostic factor in the epidural haematoma group, but the GCS score and the presence of subarachnoid haemorrhage were predictive factors in the acute subdural haematoma group. Outcomes were unfavourable in the majority of patients with intracerebral haematoma. GCS score could predict outcome in all groups. The confidence of the outcome prediction ranged from 75.8 to 92.1%, depending on logistic regression analysis.

Adolescent↗

VLCD-induced weight loss improves heart rate variability in moderately obese Japanese.

To evaluate the effects of weight reduction on the autonomic nervous system in obese patients, we investigated heart rate variability (HRV) based on 24-hr ambulatory electrocardiogram (ECG) recordings before and after weight reduction. To aim for weight reduction, 16 obese patients were treated with the very-low-calorie conventional Japanese diet (VLCD-CJ) therapy combined with behavior therapy. Percent weight reduction was 17.8% +/- 1.5% (means +/- SEM), but mean blood pressure did not change significantly after VLCD-CJ therapy. The mean normal R-R interval (mNN) of the 24-hr ECG and all other five time-domain indices increased after weight reduction. Spectral analysis revealed that weight reduction increased the high frequency (HF) component, but decreased the ratio of low to high (LF/HF) components. Rate of change in mNN or HF correlated positively with reduction rate of body mass index, but not that in LF/HF. Analysis of daily fluctuations in each HRV parameter showed that significant improvement after weight loss occurred mainly during the nocturnal period, but an HF component was improved throughout the day and night periods. These findings indicate that functional impairment of the autonomic nervous system in obese subjects, particularly in the nocturnal period, is improved by effective weight reduction after VLCD-CJ therapy.

Adult↗

Standardization of laboratory data and establishment of reference intervals in the Fukuoka Prefecture: a Japanese perspective.

Standardization of 22 clinical chemistry analytes and five serum protein constituents has been performed in the Fukuoka Prefecture, which has a population of approximately five million. The standardization project was established to determine reference intervals for these analytes by educating physicians, medical technologists and staff of medical institutions, and by daily or monthly monitoring the use of common control samples through e-mail. Standardization extended to 97% of the institutions in the prefecture. Results for 14 of the 22 clinical chemistry analytes have become highly reliable and differences between institutions decreased. Standardization of other analytes is now in progress. Regional collaboration based on international guidelines led to a significant improvement in interlaboratory comparability. Areas where further improvements are needed have been identified.

Adolescent↗

[Clinical laboratory data and reference intervals standardized in Fukuoka].

In Fukuoka whose population is approximately five million inhabitants, surveys on the accuracy of laboratory data have been performed by the Fukuoka Prefecture Medical Association for the last 30 years. We have been attempting to evaluate the data for routine use since 1988, and it has become possible to share laboratory data between all institutions in Fukuoka prefectures. As a result, reference intervals for 23 clinical chemistry analytes were established in 1995, to which were added in 1996 five serum protein constituents that have been utilized for clinical examinations. Methods for documentations and monitorings the data obtained in the prefecture were also established, standardization of the above analytes extended to 97% of the institutions in the prefecture. Results for 14 of the 23 clinical chemistry analytes have become highly reliable and clinically useful as differences between institutions in terms of results have narrowed. Standardization of other analytes is now in progress.

Aged↗

Mitochondrial gene mutations in the tRNA(Leu(UUR)) region and diabetes: prevalence and clinical phenotypes in Japan.

BACKGROUND: Mitochondrial gene mutations play a role in the development of diabetes mellitus. We have assessed the frequency of the A3243G and other mitochondrial mutations in Japan and in the relationship to clinical features of diabetes. METHODS: DNA was obtained from peripheral leukocytes of 240 patients with diabetes mellitus (39 with type 1; 188 with type 2; 13 with gestational diabetes) and 125 control subjects. We used PCR-restriction fragment length polymorphism analysis (ApaI) for A3243G and PCR-single-strand conformation polymorphism analysis to determine the mutations in the mitochondrial gene including nucleotide position 3243. RESULTS: The A3243G mutation was found in seven patients, and an inverse relationship was observed between the degree of heteroplasmy and the age at onset of diabetes. A3156G, G3357A, C3375A, and T3394C were detected in addition. Those who shared the same mutation showed similar clinical characteristics, thus representing a putative clinical subtype. The patients with A3156G had a sudden onset of hyperglycemia and showed a rapid progression to an insulin-dependent state with positive anti-glutamic acid decarboxylase antibody. Those with T3394C showed a mild defect in glucose-stimulated insulin secretion, and hyperglycemia appeared after adding such factors as aging or obesity. CONCLUSIONS: The identification of mitochondrial gene mutations allows preclinical diagnosis of diabetes and prediction of the age at onset by evaluating the degree of heteroplasmy in cases with A3243G. Mutation detection may also be important for patient management and identification of affected family members.

Adult↗

[Four cases of reversible posterior leukoencephalopathy syndrome].

We reported four children cases with reversible posterior leukoencephalopathy syndrome (RPLS). Magnetic resonance imaging (MRI) of the brain demonstrated reversible multiple cortical and subcortical lesions predominant in the occipital region. All patients presented with neurological symptoms associated with hypertension, such as headache, seizures and visual disturbances, which were successfully treated with antihypertensive therapy. Although RPLS is rare in childhood, characteristic lesions on MRI in the hypertensive children should be recognized as manifestations of RPLS. Subsequent clinical management should focus on the treatment of the hypertension and/or its underlying causes.

Adolescent↗

The effect of pentylenetetrazole-kindling on the extracellular glutamate and taurine levels in the frontal cortex of rats.

We studied the extracellular concentration of glutamate and taurine in the frontal cortex of freely-moving pentylenetetrazole (PTZ) kindled rats using an in vivo microdialysis. A significant and sustained increase in the glutamate level was observed in the kindled rats, in contrast, a slight and delayed increase was observed in the non-kindled rats when the same grade seizure was induced by PTZ. The convulsive dose of PTZ administration caused a decrease in taurine levels in the controls, however, no significant changes were found in the kindled rats.

Animals↗

Analysis of all exons of TSC1 and TSC2 genes for germline mutations in Japanese patients with tuberous sclerosis: report of 10 mutations.

Twenty-seven Japanese patients with the tuberous sclerosis complex (TSC), consisting of 23 sporadic and 4 familial cases, were tested for mutations in the TSC1 and TSC2 genes, using single-strand conformational polymorphism analysis and direct sequencing. Four possible pathogenic mutations were found in the TSC1 gene, including three frame shifts and a nonsense mutation in a familial case. All mutations were expected to result in a truncated hamartin gene product. The TSC2 gene analysis identified six possible pathogenic mutations only in the sporadic cases, including two frame shifts, one in-frame deletion, and three missense mutations. Two of the TSC2 mutations were expected to result in a truncated tuberin gene product. These results of the Japanese TSC patients were compatible with the reports from Europe and the United States, i.e., (1) TSC1 mutations are rarer in sporadic cases than in familial cases, (2) substantial numbers of sporadic cases arise from mutations in the TSC2 gene, and (3) mutations of the TSC1 gene may cause premature truncation of hamartin.

Adolescent↗

Detection of mutations in adenine phosphoribosyltransferase (APRT) deficiency using the LightCycler system.

We have applied an established technique, the polymerase chain reaction (PCR) with LightCycler technology, to a single disease with well-defined mutations. This assay produces results within only 30 min by combining PCR and fluorescence detection in one tube without electrophoretic band detection. In this study, we found 2,8-dihydroxyadenine (DHA) lithiasis in Japanese patients who were heterozygous for Japanese-type (type II) adenine phosphoribosyltransferase (APRT) deficiency (APRT*J). These patients, from a family with 2,8-DHA lithiasis, had a heterozygous mutation in the J region of the APRT gene. We demonstrated that the present system, using LightCycler technology, was simple, rapid, and reliable for detecting known mutations, and capable of identifying heterozygous and homozygous mutations in this family with APRT deficiency.

Adenine↗

Genetic alteration of the DCX gene in Japanese patients with subcortical laminar heterotopia or isolated lissencephaly sequence.

We examined mutations of the doublecortin (DCX) gene, which is responsible for X-linked subcortical laminar heterotopia (SCLH) and lissencephaly, in eight unrelated Japanese patients, four with SCLH and four with isolated lissencephaly sequence (ILS). Polymerase chain reaction (PCR) disclosed a deletion of part of the DCX gene in one male ILS patient. Single-strand conformational polymorphism analysis and subsequent sequence analysis were carried out in the remaining seven patients. One male ILS patient had a nonsense mutation in exon V, which would result in premature termination of the gene product. One female SCLH patient had a missense mutation in exon IV. Our results indicate that in the Japanese, as has been seen elsewhere, abnormality of the DCX gene is the common cause of SCLH and ILS.

Brain↗

Clinical picture of intracranial non-traumatic dissecting aneurysm.

Non-traumatic intracranial arterial dissection has been accepted as a unique entity of 'cerebral infarction in otherwise healthy young adults', and is particularly prevalent in Western countries. A recent data collection and analysis have revealed additional clinical features. The nationwide study in Japan conducted in 1996 has provided new information on the natural history and current treatment of intracranial dissecting aneurysms in Japan. The incidence of symptomatic dissection was found to be much higher in the vertebrobasilar system than in the carotid system. The mean age of the patients was 51.3 years. Patients with carotid lesions were younger (mean 43.8 years). The male/female ratio was 2: 1. Fifty-eight percent of patients presented with subarachnoid hemorrhage. Recurrence was more frequent in patients with subarachnoid hemorrhage (14%) than in patients with no hemorrhage (4.2%). Common radiological findings were dilatation, 'pearl and string' sign and narrowing of the affected artery. Surgical treatment involved a variety of procedures including proximal occlusion, entrapment, wrapping and endovascular embolization. Patients with subarachnoid hemorrhage (61%) underwent surgical treatment more frequently than patients with no hemorrhage (17%). Good recovery was achieved in 64% of all patients. Outcome was better in patients with no subarachnoid hemorrhage compared with those with hemorrhage.

Aortic Dissection↗

Risk factors for poor outcome of untreated arteriovenous malformation.

This study was conducted to determine risk factors for poor outcome in the natural history of arteriovenous malformation (AVM). We statistically analysed the correlation between clinical or angiographical findings and clinical outcomes for 55 cases of untreated AVM. Subsequent haemorrhage from AVMs was the only significant risk factor for poor outcome (P< 0.0001). The odds ratio was 44.56 with a 95% confidence interval (CI) from 4.80 to 413.90. Risk factors for subsequent haemorrhage from AVMs were also determined. The size (P = 0.0483) and location (P = 0.0147) of an AVM were significant risk factors for subsequent haemorrhage. The odds ratios were 3.97 with a 95% CI from 1.18 to 13.33 and 3.89 with a 95% CI from 1.10 to 13.72, respectively. AVMs of more than 60 mm, and deep or infratentorial AVMs had more chance of subsequent haemorrhage, and hence of a poor outcome. We propose using an aggressive multidisciplinary approach to treating these AVMs.

Adolescent↗

Suppression of insulitis and diabetes in B cell-deficient mice treated with streptozocin: B cells are essential for the TCR clonotype spreading of islet-infiltrating T cells.

In order to clarify the role of B cells in the development of insulitis and diabetes, B cell-deficient (B(-)) mice treated with streptozocin (STZ) were studied. The extent of insulitis and the cumulative incidence of diabetes were significantly suppressed in B(-) mice (P < 0.0001), indicating that B cells are crucial for the progression of insulitis and diabetes. Accumulation of both CD4(+) T cells and B cells was observed in islets of B(+) mice, while CD4(+) T cells but not B cells were found in B(-) mice. A few CD8(+) T cells and macrophages were detectable in both types of mice. The immunohistochemical study did not reveal any change in the subpopulations of infiltrating lymphocytes except for the absence of B cells in the B(-) mice. TCR V(beta) gene repertoire usage of islet-infiltrating T cells was restricted to some extent in the B(+) or B(-) mice, but there was no significant difference between the B(+) and B(-) mice, suggesting that the initial islet-reactive T cell response can occur in the absence of B cells. In contrast, TCR clonotype spreading of islet-infiltrating T cells was significantly suppressed in B(-) mice compared with B(+) mice (P < 0.0001). These data suggest that initial priming of T cells is not impaired and TCR V(beta) repertoire usage is not limited by the lack of B cells, while B cells are important essentially for the spreading of islet-infiltrating clonal T cells in autoimmune diabetic mice induced with STZ.

Animals↗