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M Maehara

Publications and source records attributed to M Maehara.

At least 37 records · Page 2Linked to original sources
PubMed1991

Increment of alpha B-crystallin mRNA in the brain of patient with infantile type Alexander's disease.

To estimate the expression level of alpha B-crystallin in the brain of infantile type Alexander's disease, the amounts of protein and mRNA of alpha B-crystallin were measured by enzyme immunoassay (EIA) and Northern blot analysis, respectively, in the brain of patient and controls, and in the tissues from glioblastoma and astrocytoma. The alpha B-crystallin protein in the brain of patient was remarkably increased as compared with those of controls. The amount of alpha B-crystallin mRNA of patient was increased about 7-fold compared to the mean value of the control group and higher than that of glioblastoma tissue. These data suggest that increment of alpha B-crystallin mRNA in astrocytes leads to the overexpression of this protein and may be one of the main causes of infantile type Alexander's disease.

Adolescent↗
PubMed1991

Detection of platelet mitochondrial DNA deletions in Kearns-Sayre syndrome.

To establish a noninvasive genetic diagnosing method for Kearns-Sayre syndrome, the authors used the polymerase chain reaction (PCR) technique for detecting mitochondrial DNA (mtDNA) deletions in the platelets and directly sequenced the crossover regions of the deleted mtDNA using the fluorescence-based automated sequencing system. The mtDNA deletions were identified in the platelets of three of four patients. The sizes and locations of deletions were determined by the nesting primer PCR method, in which the primary PCR products derived from deleted mtDNAs undergo reamplification using a series of nesting primers. With the fluorescence-based sequencing of templates amplified by the asymmetric PCR method, deleted mtDNA was sequenced directly without cloning. In patient 1, guanine (G) was found at the boundaries of a deleted segment spanning 8400 base pairs (bp) between the CO1 and ND6 genes. In patient 2, a 9-bp directly repeated sequence of 5'-ACCTCCCTC-3' (where A = adenine, C = cytosine, and T = thymine) was found at the boundaries of a deleted segment spanning 7221 bp between the CO1 and ND5 genes. In patient 3, an 8-bp sequence of 5'-TCGCTGTC-3' was found at the boundaries of a deleted segment spanning 4664 bp between the ATPase6 and ND5 genes. Deletions were not detected in the mtDNA of patient 4 or in that of the mothers of the patients. Previously, the genetic diagnosis of this syndrome required muscle biopsy specimens and the use of Southern blot analysis. However, this method requires neither muscle biopsy nor isotopes and is more rapid than the Southern blot method.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Measurement of alpha-ketoglutarate dehydrogenase activity in tissue extracts and human platelets using reversed-phase high-performance liquid chromatography.

A new method for the determination of the activity of alpha-ketoglutarate dehydrogenase complex (KGDHC) in mouse brain and liver mitochondria and in human platelets using reversed-phase high-performance liquid chromatography is described. This method is based on the quantification of succinyl-CoA formed in the reaction catalyzed by KGDHC. Succinyl-CoA was separated using a YMC-Pack C8 column employing isocratic elution and detected spectrophotometrically at 254 nm. The detection limit of succinyl-CoA was 0.05 nmol. Succinyl-CoA in the supernatant of the assay mixture was stable for several hours at 4 degrees C and for a week when stored at -20 degrees C. The KGDHC assay showed good linearity with time and added protein, and all tissues demonstrated an absolute requirement for added alpha-ketoglutarate, nicotinamide dinucleotide, and coenzyme A and partial or no requirement for thiamine pyrophosphate, magnesium chloride, and dithiothreitol. The specific activities in liver and brain mitochondria and platelet homogenates determined by the present method were 19.2 +/- 0.9, 18.1 +/- 2.8, and 2.6 +/- 0.3 nmol/min/mg protein, respectively. In human platelets, the present method gives higher specific activity and lower blank values than a prior method using 14CO2 and may be useful in the diagnosis of KGDHC deficiency. This method is simple, rapid, and can be readily employed for the determination of KGDHC activity in various animal tissues and human platelets.

Acyl Coenzyme A↗
PubMed1990

Seizure prognosis and EEG evolution in complex partial seizures of childhood onset.

We studied the clinical course and seizure prognosis of 126 children with complex partial seizures regularly followed up for more than 4 years in our clinic. Clinical and EEG features of 63 seizure-free patients were compared with those of 63 patients with persistent seizures. The features contributing to poor prognosis were 1) mental retardation, 2) a history of status epilepticus and 3) abnormal basic rhythm in EEG. CT abnormality, a history of febrile convulsions (FC), the clustering of seizures and association with other types of seizures did not influence prognosis. We divided the patients into four groups according to the evolutionary pattern of seizure discharges: Group A, 55 (43.7%) patients with spike focus always fixed in the same region; Group B, 20 (15.9%) patients with wandering foci; Group C, 10 (7.4%) patients with multifocal spikes; and group D, 41 (32.5%) patients with no focal discharges. There was no difference in seizure prognosis among these four groups, but the patients with a focus in the anterior temporal region in Group A evidenced the worst prognosis.

Adolescent↗
PubMed1990

Benign infantile epilepsy with complex partial seizures.

Benign infantile epilepsy with complex partial seizures is characterized by a high incidence of family history of benign childhood convulsions, normal development prior to onset, infantile onset, no underlying disorders, no neurological abnormalities, normal interictal EEGs, good response to treatment, and complete remission with normal developmental outcome. Seizures often occur in clusters, consisting of motion arrest, decreased responsiveness, staring or blank eyes mostly with simple automatisms, and mild convulsive movements associated with focal paroxysmal discharges, most frequently in the temporal area.

Electroencephalography↗
PubMed1990

[Two cases of tubular adenoma of the breast].

Two rare cases of a tubular adenoma of the breast are reported, together with a clinicopathological review of the pertinent literature. Only 14 cases of this histological type have so far been reported in Japan. Both patients were single women aged 22 and 34 years, respectively. In case 1, a mass was found in the axilla, and in case 2, a breast cancer was simultaneously found in the contralateral breast. In each patient, a mass that measured 2 cm in diameter was oval, elastic and firm and smooth on the surface. In each instance the result of the biopsy performed led to a diagnosis of a fibroadenoma. Microscopically, the tumor was sharply demarcated from the adjacent breast tissue and consisted of homogeneous epithelial cells with small tubular structures and a minimal stromal component.

Adenoma↗
PubMed1989

Magnetic resonance imaging in complex partial seizures.

Magnetic resonance imaging (MRI) and computed tomography (CT) were performed on 45 patients with intractable complex partial seizures. MRI was performed with a superconducting whole-body scanner operating at 0.5 tesla (T) and 1.5 T. In patients with temporal lobe epilepsy, 8 of 24 patients had abnormal CT, but 16 of 24 patients showed abnormal MRI. 1.5 T MRI detected more abnormality than 0.5 T MRI when CT was normal. In patients with frontal lobe epilepsy, 5 of 7 patients had normal CT and MRI. In 2 other patients, MRI demonstrated an arachnoid cyst and increased signal intensity area on the T2-weighted images which were not detected by CT. In patients with occipital lobe epilepsy, 5 of 6 patients show abnormal CT and MRI. In patients with tuberous sclerosis, MRI revealed some increased signal intensity areas on the T2-weighted images in the occipital and temporal lobe, which were not detected by CT. Most surface EEG foci corresponded with the side of MRI abnormality. These data indicate that MRI is more informative than CT in complex partial seizures. MRI is the imaging technique of choice in the diagnosis of complex partial seizures.

Adolescent↗
PubMed1988

A simple fluorometric method for the determination of serum free carnitine.

A new fluorometric method for the determination of serum free carnitine is described. The addition of carnitine to a system containing carnitine acetyltransferase (EC 2.3.1.7) and acetyl-CoA gives rise to the formation of CoA. The system is coupled to N-(p-(2-benzimidazolyl)-phenyl)-maleimide (BIPM). A fluorescent agent, CoA-BIPM, is produced proportionally to concentration of carnitine. By measuring the fluorescence intensity of BIPM, the carnitine content of serum can be determined. The coefficients of variation, within-run and between-run, of the method were 5.2 and 2.6%, respectively. Recovery of carnitine added to serum was 98-113%. Comparison with a colorimetric method showed a good correlation (r greater than 0.90). The method has sufficient sensitivity to measure concentrations as low as 10 mumol/l.

Adult↗
PubMed1987

Enzyme replacement therapy in a patient with hyperargininemia.

In a patient with hyperargininemia, enzyme replacement therapy such as whole blood exchange transfusion or erythrocyte transfusion was performed, and its effect was confirmed in vitro as well as in vivo. The patient has been treated with the restriction of protein intake, oral administration of an essential amino acid mixture, and sodium benzoate or phenylacetic acid. With these treatments, his plasma ammonia levels were controlled. On the other hand, plasma and CSF concentrations of arginine were not so well controlled. With whole blood exchange transfusion and erythrocyte transfusion, plasma arginine concentrations and plasma ammonia levels were controlled. These effects have continued for about 3 months. Furthermore, the effect of exchanged erythrocytes on the blood arginine levels was also confirmed by in vitro experimentation that mixes arginine with erythrocytes in the medium RPMI 1640. Arginine concentration of the medium did not decrease when arginine was mixed with erythrocytes of the patient, but when arginine was mixed with erythrocytes of mother or normal controls, it decreased rapidly. In calculation, 10(7) of erythrocytes of the mother or normal controls was presumed to metabolize 4-5 nmole of arginine per day. From these results, the erythrocyte exchange transfusion is considered to be effective for the control of clinical and biochemical abnormalities in this disorder.

Amino Acid Metabolism, Inborn Errors↗
PubMed1987

Development of the beta activities in children: an EEG-topographical analysis.

We investigated the characteristics of beta activities during drowsiness and very light sleep in 61 children using topographical analysis. The average power of beta activities was posterior-dominant in infancy, and it became frontal-dominant as the age increased. These topographical changes occurred earlier in the low frequency bands than the high frequency bands. The total power of the high frequency bands was larger in infants, and with increasing age that of the low frequency bands predominated. The developmental changes of the beta activities considered to be induced by drugs were similar to those of children without drugs.

Adolescent↗
PubMed1985

Treatment of subacute sclerosing panencephalitis with human leukocyte interferon.

In five patients with subacute sclerosing panencephalitis (SSPE), human leukocyte interferon (IFN) therapy was tried. IFN was administered intramuscularly, intravenously, and intrathecally. The total dose of administered IFN ranged from 13 X 10(6) to 116.92 X 10(6) IU. There were no severe side effects except for temporary high fever and vomiting. Observation of the clinical course were made for 26-60 months. At the beginning of the treatment, one of the patients was at the first stage of Jabbour's classification and the other four at the second stage. No clinical improvement was observed and the clinical course was progressive in all patients. At present, one of the patients was at the second stage and the other four were at the fourth stage. EEGs showed progressive deterioration, and cranial CT scan demonstrated progressive cortical atrophy and ventricular enlargement. Measles antibody titers in the serum and CSF also unchanged. On the other hand, permeability of IFN at blood-brain barrier (BBB) was relatively good.

Child↗