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Biomedical subjects

K Nihei

Publications and source records attributed to K Nihei.

At least 55 records · Page 3Linked to original sources

Japan-Russia Pediatric Society.

In March 1990, medical interchange between Japan and the Soviet Union began with a letter from the local health bureau of Khabarovsk. We visited Khabarovsk three times and Kamchatka once, and saw many hospitals and patients. Russian doctors of pediatrics visited Japan. Medical information was exchanged and discussed. The Japan-Russia Pediatric Society was established to perform interchange of medical information, technology and staff such as doctors, nurses and technicians between Japan and Russia, especially the Far East district of Russia. The Society meeting has been held three times: Tokyo (1991), Khabarovsk (1992) and Niigata (1993). It is necessary to continue the interchange between the two countries.

International Cooperation↗

Marked increase in cerebrospinal fluid ubiquitin in Creutzfeldt-Jakob disease.

We have established the radioimmunoassay for ubiquitin in the cerebrospinal fluid (CSF) and measured the ubiquitin concentration in CSF from 4 cases of neuropathologically verified Creutzfeldt-Jakob disease (CJD), 10 cases of multi-infarct dementia (MID), 7 cases of senile dementia of Alzheimer type (SDAT), and 18 controls. The normal values were determined to range from 7.3 to 21.0 ng/ml, 14.3 +/- 1.1 ng/ml in the mean +/- S.E.M. The CSF ubiquitin levels in the cases of MID and SDAT were 16.6 +/- 6.4 ng/ml and 21.3 +/- 6.1 ng/ml, respectively. In the cases of CJD, the CSF ubiquitin was markedly increased at the early and middle stages of the disease (230.6 ng/ml in Case 1, 107.6 ng/ml in Case 2, 212.5 ng/ml in Case 3, and 377.0 ng/ml in Case 4) and these gradually decreased as the disease progressed. The measurement of CSF ubiquitin seems useful to make an early diagnosis of CJD.

Aged↗

Neurofilament and neural cell adhesion molecule immunocytochemistry of Huntington's disease striatum.

We examined normal and Huntington's disease (HD) human striatum with specific monoclonal antibodies to nonphosphorylated (SMI 32) and phosphorylated (SMI 31) neurofilament and neural cell adhesion molecule (NCAM). SMI 32 identifies medium-sized neuronal perikarya and dendrites in normal striatum. Axons are not immunoreactive. In high-grade HD striatum (grades 3 and 4) SMI 32 neurons are morphologically abnormal and significantly depleted. Dendritic arbors are intensely immunoreactive, tortuous, and fragmented, especially in the subependymal zone. Proliferative SMI 32-positive sprout-like structures and axon-like processes are seen. SMI 31 normally stains a fine meshwork of axon-like processes that become intensely immunoreactive, condensed, convoluted, and fragmented in HD. NCAM staining is minimal in normal striatum, but, in HD striatum, many dot- and thread-like structures are found, especially in the subependymal region. The abnormalities revealed by SMI 31, SMI 32, and NCAM suggest that neurofilament phosphorylation is altered and growth related proteins are reexpressed in HD. Dephosphorylation and destabilization of the cytoskeleton may contribute to neuronal injury and death in HD.

Aged↗

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS): a correlative study of the clinical features and mitochondrial DNA mutation.

We studied 40 MELAS patients (21 male and 19 female) to characterize the clinical features and biochemical and muscle biopsy findings related to the mtDNA mutation at the nucleotide position of 3,243, the most common genetic defect in MELAS. The most frequent symptom was episodic sudden headache with vomiting and convulsions, which commonly affected patients aged 5 to 15 years (80%). Biochemical defects in the muscle were variable; 13 patients had complex I, seven complex IV, and four complexes I + IV deficiencies. In four muscle biopsies without ragged-red fibers or any enzyme defect, we based the diagnosis on the identification of strongly SDH-reactive blood vessels, which occurred in 87.5% of the biopsies. The mtDNA mutation was present in 32 of 40 patients (80%). We conclude that there are no clinical and pathologic differences between the patients with and without this mtDNA mutation.

Acidosis, Lactic↗

[Reducing body myopathy--a case report].

A 2-year-old girl with reducing body myopathy was reported. She had no family history of neuromuscular disease. She developed normally with no delay in milestones during infancy. She had no muscle weakness or hypotonia up to 2 years of age when she received mumps vaccination. Three days after the injection, she was first noticed to have limb muscle weakness. The muscle weakness progressed rapidly with increasing difficulty in gait and raising the upper arms, particularly the left. Four months later, she had difficulty in keeping her head up and could no longer climb the stairs. On physical examination, she had proximal dominant generalized muscle weakness, with a preferential neck muscle involvement. She walked waddlingly and stood up with Gowers' maneuver. Facial and ocular muscles were intact. No dysarthria, dysphagia or respiratory difficulty was noted. EMG showed myopathic pattern. Serum creatine kinase level was moderately elevated to 739 IU/l. In the biopsied left biceps muscle, there was marked variation in fiber size, but no apparent necrotic or regenerating fibers. The most striking feature was the presence of numerous eosinophilic inclusions which reduced nitroblue tetrazolium (NBT) and were, therefore, stained dark with menadione-linked alpha-glycerophosphate dehydrogenase even without the substrate of menadione, showing the histochemical characteristics of "reducing" body. The bodies were predominantly seen in fibers with disorganized intermyofibrillar networks and with high acid phosphatase activity. On electron microscopy, the reducing bodies consisted of fine granular material with the similar electron density to the chromatin granules and were located mostly around the degenerated nuclei, suggesting the nuclear degeneration playing a role in forming the reducing bodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗

[Determination of serum interleukin-6 concentration by an enzyme-linked immunosorbent assay in patients with paraproteinemia].

A sensitive enzyme-linked immunosorbent assay of human interleukin-6 (IL-6) was developed to measure the serum IL-6 by Fujirebio INC. Its sensitivity was 3 pg/ml and its analytical range was from 3 to 200 pg/ml. Its precision, reproducibility, and sensitivity were quite satisfactory. The serum IL-6 levels in 200 normal individuals were less than 3 pg/ml. Serum IL-6 concentration in patients with malignant and benign monoclonal gammopathy (BMG) was determined by an ELISA. Serum IL-6 concentration in patients with Bence Jones protein (BJP) type multiple myeloma (MM) (n = 12) was 12.3 +/- 12.7 (mean +/- SD) pg/ml, BJP and IgG type MM (n = 4) 11.5 +/- 5.8 pg/ml, IgM type MM (n = 11) 11.1 +/- 17.5 pg/ml and IgA type MM (n = 4) 4.0 +/- 1.4 pg/ml. They were significantly higher in BJP, BJP and IgG, and IgM types than in normal individuals. The cases with the serum IL-6 of more than 10 pg/ml were move frequent in MM (32.8%) than in BMG (16.3%). The correlation between the serum IL-6 and C-reactive protein (CRP) was r = 0.563 in patients with MM (n = 61) and r = 0.498 in BMG (n = 43). Besides, during the clinical course of a patient with IgG-lambda and BJP-lambda type MM, serum IL-6 concentration responded more sharply than CRP and WBC on candida infection. The measurement of serum IL-6 therefore, seemed not useful for differential diagnosis of monoclonal gammopathies, but it seemed useful as an acute phase protein as well as CRP.

Enzyme-Linked Immunosorbent Assay↗

Respiration-deficient cells are caused by a single point mutation in the mitochondrial tRNA-Leu (UUR) gene in mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS).

MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes) is a major subgroup of heterogeneous mitochondrial diseases. For identifying a mutation in the mitochondrial gene, we isolated, from the same muscle tissue from a patient with MELAS, cell lines with distinctly different phenotypes: one was respiration-deficient, and the other was apparently normal. Compared with the normal cells, only one A-to-G nucleotide transition at nucleotide 3243 in the tRNA-Leu (UUR) gene was found in whole mtDNA of the respiration-deficient cells. This mutation was also found in eight patients, from unrelated families, who had MELAS in a heteroplasmic manner but was not found in control individuals. Therefore, the single point mutation causes the functional abnormality in the respiratory chain of mitochondria.

Acidosis, Lactic↗

A point mutation in the mitochondrial tRNA(Leu)(UUR) gene in MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes).

Mitochondrial myopathy, encephalopathy, lactic acidosis and strokelike episode (MELAS) is a major group of heterogeneous mitochondrial disorders. To identify the defective gene, mitochondrial DNA from a patient with MELAS was sequenced by using amplified DNA fragments as sequencing templates. In 14.1 kbp determined out of 16.6 kbp of the whole mitochondrial gene, at least 21 nucleotides were different from those of a control human mitochondrial DNA. One of the substitutions was a transition of A to G in the tRNA(Leu) (UUR) gene at Cambridge nucleotide number 3,243. This nucleotide is conserved not only in many mitochondrial tRNAs but in most cytosolic tRNA molecules. An Apa I restriction site was gained by the substitution of this nucleotide. The Apa I digestion of the amplified DNA fragment revealed that all independent 6 patients had G at nucleotide number 3,243 in their mitochondrial DNAs, but none of 11 control individuals had G at this position. This result strongly suggests that the mutation in the mitochondrial tRNALeu gene causes MELAS.

Acidosis, Lactic↗

Studies on pediatric patients with absent auditory brainstem response (ABR) later components.

Eleven pediatric patients with only wave I or waves I and II of their ABR were clinically analyzed. The clinical diagnoses of these patients were as follows: 1) anoxic encephalopathy in two cases; 2) neonatal asphyxia in one; 3) infantile Gaucher's disease in one; 4) mitochondrial encephalomyopathy in one; 5) suspected Pelizaeus-Merzbacher disease in three; 6) degenerative disease of unknown etiology in two (presumptive diagnosis were progressive supranuclear palsy and dentate-rubro-pallido-Luysian atrophy); and 7) infantile spasms with congenital malformation of the brain and bones in one. The incidence of the patients with this type of ABR abnormality was 0.67% among 1,650 of our pediatric patients whose ABRs were examined because of audiological or neurological problems. All eleven patients showed severe mental retardation. Nine of the eleven had convulsions and likewise, eight of eleven showed deterioration in mental and/or motor activities. Furthermore seven of eleven had disturbed consciousness and four of these seven were in deep coma. Other brainstem and bulbar signs and symptoms were frequently found in these patients. In our series, patients without the later components of ABR manifested marked neurological abnormalities inside and outside the brainstem.

Adolescent↗

Cranial computed tomographic and magnetic resonance imaging studies on the Rett syndrome.

We reported here 5 cases with the Rett syndrome (RS) who fulfilled the criteria for RS. The changes in CT and MRI findings with the clinical course were studied. Cortical atrophy especially in the frontal area, progressed gradually with the clinical progression after 2 years old in CT. In axial sections on MRI, frontal atrophy was also demonstrated. The white matter, basal ganglia, thalamus and hypothalamus area were all normal. In midline sagittal sections, corpus callosum was hypoplastic, and widening of prepontine cistern and narrowing of the brainstem were demonstrated in some cases. There was no significant atrophy of the cerebellum, amygdala and hippocampus. Follow-up studies including CT and MRI are necessary to evaluate brain morphology in RS.

Child↗

[Mixed type total anomalous pulmonary venous connection with the left upper pulmonary vein draining into the innominate vein and the other pulmonary veins into the coronary sinus--surgical correction in 2 infants].

Surgical repair of the mixed type total anomalous pulmonary venous connection (TAPVC) in infancy is known to be difficult. In this report, experience of two infants with the mixed type TAPVC with the left upper pulmonary vein (PV) draining into the innominate vein and the other PVs into the coronary sinus (IIa + Ia (left upper PV) type TAPVC) is presented. In such cases, it has been said that the left upper PV should be left uncorrected, but we anastomosed the left upper PV, that was thin and fragile, to the left atrium and corrected all the other anomalous PVs. The results were satisfactory. Recently, Extra-Corporeal circulation, microsurgery, and other techniques have significantly progressed, so we consider that the anastomosis is possible in most infants with IIa + Ia (left upper PV) type TAPVC. In the future, careful clinical follow-up and repeat catheterizations should be done, and we'd like to examine the long term patency of the left upper PV.

Anastomosis, Surgical↗

[Breast carcinoma with features of osteosarcoma--a light and electron microscopic and immunohistochemical study].

Reported is the case history of a 58-year-old woman with a lump in the left breast. The tumor was composed of two nodules, sharing a common portion. Grossly, one was an irregular hard tumor that was grayish in color, and the other was a well circumscribed cystic tumor that showed necrosis and a hemorrhage that had filled it with a reddish soft mass. Light microscopically, combined features of a scirrhous carcinoma and of an osteosarcoma were observed in each nodule, but the common portion was consistent with a metaplastic carcinoma, with cancer cells and sarcoma-like cells closely mingled. An ultrastructural study showed that the sarcoma-like cells were composed of polymorphic cells that resembled osteoblasts, myofibroblasts, osteoclasts, histiocytes, and undifferentiated tumor cells. Immunohistochemically, vimentin and alpha 1-antitrypsin in the sarcoma-like cells were positive, suggesting these cells were of a mesenchymal rather than of an epithelial origin.

Adenocarcinoma, Scirrhous↗

[Design and application of laser-disk for clinical pulmonary data base system using the personal computer].

A database system is described for managing the information on pulmonary function test (PFT) measured by three different PFT devices. The data is transmitted into a personal computer, FM-11AD2+ (FUJITSU CO., LTD.) with a 20 MB hard disk and a 800 MB laser disk. Multitasking OS, OS-9/6809, is used to operate the software. PFT data of about 15,000 cases may be stored, which can be easily retrieved for research and discussions on a case study. Despite the present limitation of the processing speed and the capacity of the hard disk, this system is useful because it allows to provide reports readily.

Database Management Systems↗

[Clinical diagnoses of pediatric patients without detectable auditory brainstem response (ABR)].

One hundred and forty-seven out of 1,600 infants and children showed no detectable ABR. ABRs were evoked by clicks. As to hearing acuity, 121 out of 147 patients had sensorineural hearing loss and 19 had no hearing impairment of high frequency (3-4 kHz) and high sound intensity (85-90 dBnHL). Eight patients could not be diagnosed whether they had hearing impairment or not. Among 19 patients who did not have sensorineural hearing loss in those ranges described above, 5 patients had cerebral palsy with severe mental retardation, 4 had mitochondrial encephalomyopathy, 3 had degenerative disease of unknown etiology, 2 patients had Down syndrome, 1 was a low birth weight infant with respiratory distress syndrome, 1 was a neonate born to a diabetic mother, 1 experienced severe neonatal asphyxia, 1 patient had acute lymphoblastic leukemia and 1 infant was later confirmed as a healthy girl. Of these, four patients showed transiently negative response in ABR. Nine patients remained undiagnosed as to hearing because they were in deep coma, had profound brain damage, or died in early neonatal period. They had major neurological diseases: severe neonatal asphyxia, holoprocencephaly, microcephaly, degenerative diseases of the central nervous system of unknown origin, metachromatic leukodystrophy, trisomy of chromosome 18, anoxic encephalopathy, small for gestational age newborn with intracranial bleeding and posthemorrhagic hydrocephalus. When ABR cannot be recorded using high sound intensity clicks, it usually suggests presence of hearing impairment of high frequency range. However, there are patients who have no hearing impairment in those sounds.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗

Findings in muscle in complex I (NADH coenzyme Q reductase) deficiency.

Thirteen of 15 patients with complex I deficiency had the multisystemic form, with strokelike episodes and other symptoms that fulfilled the diagnostic requirements for MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes), and 2 had only muscle fatigability and weakness, having the purely myopathic form. In the multisystemic form, 12 patients had ragged-red fibers. All multisystemic patients had myopathic histochemical abnormalities that consisted of mild to moderate variation in fiber size, disorganized intermyofibrillar networks, type 2 fiber atrophy, and an increased number of type 2C fibers. Five of 13 multisystemic patients had decreased cytochrome c oxidase (CCO) activity in extrafusal fibers, with sparing of intrafusal muscle fibers. In the myopathic form, pathological findings were similar to those in the multisystemic form. In addition to complex I and NADH dehydrogenase activities being decreased, the CCO activity was significantly decreased (less than 50% of control value) in 8 patients, especially when the disease was in its advanced stages, suggesting that CCO enzyme might be secondarily affected as the disease progresses.

Adolescent↗

Muscle pathology in cytochrome c oxidase deficiency.

Muscle biopsies from 16 patients with cytochrome c oxidase (CCO) deficiency were examined morphologically. Two siblings had the fatal infantile form. The muscle of the older sister at the age of 5 months had numerous ragged-red fibers (RRF) and increased numbers of lipid droplets; at 28 days the brother had no RRF suggesting that the RRF formed later than 28 days. The muscle pathology in two patients with the benign infantile form improved as they grew older; numbers of RRF, lipid droplets and glycogen particles decreased and CCO activity increased in the second biopsy. In the encephalomyopathic form, RRF were seen in 5 of 12 muscles mostly in patients more than 6 years of age. Muscle spindles and blood vessel walls in the biopsies from three patients with rapid clinical aggravation had no CCO activity, suggesting that enzyme activity differed from tissue to tissue (tissue specificity).

Adolescent↗