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Biomedical subjects

H Fujimura

Publications and source records attributed to H Fujimura.

At least 19 recordsLinked to original sources

Mitochondrial tRNA(Ile) mutation in fatal cardiomyopathy.

A patient with mitochondrial encephalomyopathy who died from progressive intractable cardiac failure at the age of 18 is reported. At the age of 4, he presented with short stature, but multiorgan disorders including deafness, focal glomerulosclerosis, epilepsy and dilated cardiomyopathy appeared later in his clinical course. Laboratory tests showed hyperlactatemia and hyperpyruvatemia. Histopathological findings demonstrated mitochondrial myopathy with ragged red fibers and focal cytochrome C oxidase-deficient fibers in skeletal and cardiac muscles. The activity of cytochrome C oxidase was 30% less than the control level in skeletal muscle. Sequencing of the entire mitochondrial tRNA genome revealed a novel point mutation in the tRNA(Ile) region (nt 4269). This A-to-G substitution was found in none of the 30 controls by screening using mispairing PCR and Ssp I digestion methods, suggesting that this new mutation was pathogenic in our case.

Adolescent

Molecular monitoring of the transcriptional activation of the yeast Saccharomyces kluyveri mating pheromone signal transduction by using FUS1-lacZ fusion gene.

To analyse the molecular mechanism by which a mating pheromone signal is transmitted in Saccharomyces kluyveri, the S. cerevisiae FUS1-lacZ fusion gene was introduced into S. kluyveri cells and its transcriptional activation was investigated. The expression of FUS1-lacZ fusion product was cell-type-specifically induced by pheromone treatment in S. kluyveri. The result suggests that S. kluyveri pheromone signal may be transduced by a mechanism similar to that in S. cerevisiae. This system may provide a model for analysing the molecular mechanism of the mating reaction in Saccharomyces kluyveri.

Conjugation, Genetic

Transfer of multiple sclerosis into severe combined immunodeficiency mice by mononuclear cells from cerebrospinal fluid of the patients.

To investigate the mode of the pathogenesis of multiple sclerosis (MS), we transferred cerebrospinal fluid (CSF) cells, predominantly mononuclear cells, from MS patients at both exacerbation and remission stages of the disease into severe combined immunodeficiency mice by intracisternal injection. As controls, (i) CSF cells from patients with cervical spondylosis and (ii) peripheral blood mononuclear cells from normal individuals were transferred. Four to 6 weeks after transfer, most mice transferred with CSF cells from MS patients at the exacerbation stage of the disease developed paralysis and ataxia. The histopathological examination on the sacrificed mice revealed multiple scattered, discrete lesions localized in the white matter of the brainstems and spinal cords. These lesions were characterized by various degrees of tissue necrosis, involving inflammatory-cell infiltration. Most infiltrating cells were macrophages, although a smaller number of granulocytes appeared in several foci. Reactive astrocytic gliosis was also seen around the necrotic foci. Furthermore, these lesions exhibited demyelination. These histopathological changes are similar to those seen in MS. In contrast, none of the severe combined immunodeficiency mice transferred with CSF cells from MS patients at the remission stage of the disease, or with CSF cells from the patients with cervical spondylosis, or with peripheral blood mononuclear cells from normal individuals showed any such histopathological changes. These observations provide convincing direct evidence of encephalitogenicity of mononuclear cells in CSF from MS patients at the exacerbation stage of the disease.

Animals

Familial amyloid polyneuropathy related to transthyretin Gly42 in a Japanese family.

A Japanese family is described in which 6 persons showed familial amyloid polyneuropathy (FAP). Mean ages of onset were 38 for 4 males and 54 for 2 females. Three of the 6 became emaciated and died after 4 to 10 years. In 5, muscular weakness and autonomic dysfunction were the initial symptoms followed by sensory disturbances. Amyloidotic cardiomyopathy was present in 3 of the subjects. Amyloid deposits showed an immunohistological relation to transthyretin (TTR). Analysis of 1 patient's TTR gene revealed a single base change (A----G) that led to amino acid substitution (Glu42----Gly). This base change produced a new restriction site for endonuclease Cfr13 I in exon 2. Polymorphic analysis of the length of the Cfr13 I-restriction fragment confirmed the base change, and made it possible to detect the mutant TTR Gly42 gene in the FAP subjects. Amino acid sequencing analysis showed a variant of TTR Gly42 in 1 patient's serum.

Adult

A case of pigmentary type of orthochromatic leukodystrophy with early onset and globoid cells.

We report herein a sporadic case of the pigmentary type of orthochromatic leukodystrophy with early onset and very rapid clinical course. The patient's development was normal until 2 years old, when he experienced visual disturbance. Rapid deterioration resulted in death 1.5 years after the onset. Metachromatic leukodystrophy, globoid cell leukodystrophy and adrenoleukodystrophy were excluded by biochemical assays. Autopsy findings were compatible with the diagnosis of the pigmentary type of orthochromatic leukodystrophy. However, there were unique findings of severe neuronal loss and the collection of globoid-like cells in the interface of the gray matter and the white matter. Immunohistochemical staining of myelin basic protein, proteolipid protein and galactocerebroside demonstrated that these myelin constituents were equally preserved in the posterior column, while absent in the lateral and anterior columns of the spinal cord.

Autopsy

Amyloid polyneuropathy with transthyretin Arg50 in a Japanese case from Osaka.

A Japanese patient with systemic amyloidosis associated with a transthyretin (TTR) variant Arg50 is presented. This 41-year-old man became impotent and developed decreased pain sensation in his hands, and then sensory loss and muscle wasting in his lower legs, and cardiomyopathy appeared. The symptoms progressed and he died of congestive heart failure at age 46. There were amyloid deposits in all organs studied and massive amyloid deposition was seen in the peripheral nerves and cardiac muscles. Amyloid fibrils extracted from heart tissue contained TTR. A genetic mutation, causing a Ser50-->Arg substitution of the TTR molecule, was identified in another family member. Plasma TTR was shown to be a mixture of normal TTR Ser50 and mutant TTR Arg50 in the 2 subjects.

Adult

Application of ultrasonic probes prior to endoscopic resection of early gastric cancer.

The development of a new strip biopsy technique for endoscopic mucosectomy utilizing endoscopic saline injection and a double-channel endoscope permits the safe and simple resection of superficial type early gastric cancer which has been difficult to perform with conventional polypectomy techniques. Preresection assessment of the depth of invasion and postresection assessment of efficacy are important with regard to treatment of early gastric cancer, but conventional endoscopic ultrasonography employed for this purpose requires special equipment and involves intricate procedures. An ultrasonic probe which can be used endoscopically has recently been developed and is currently in the trial stage. The authors have conducted studies with respect to a 7.5 MHz radial scanning type Miniature Ultrasonic Probe as well as a 20 MHz manual linear scanning type Sonoprobe System. Experimental studies indicated that the former type is capable of delineating postresection ulcers, while the latter permitted delineation of tumors as hypoechoic images in 9 of 11 cases of early gastric cancer.

Adenocarcinoma

Familial amyloid polyneuropathy associated with the transthyretin Cys114 gene in a Japanese kindred.

A Japanese kindred with dominantly inherited amyloid polyneuropathy, commonly called familial amyloid polyneuropathy (FAP), has been identified. Amyloid protein was transthyretin (TTR) related and the patients were heterozygous for the mutant gene encoding TTR with a single amino acid substitution of cysteine for tyrosine at position 114. This family originated in Nagasaki Prefecture, Japan, and 12 of the 36 known members of six generations have been affected. The initial symptoms occurred in their thirties with the cardinal features of polyneuropathy, vitreous opacities and cardiac disease. Sensory neuropathy was severe in the lower limbs. Autonomic disturbances, especially postural hypotension, were the most debilitating to the patients. Amyloid deposits were detected widely in most organs except for the central nervous system. The duration from the onset of the disease to death was within 10 yrs. Heart failure caused by heavy amyloid deposits was the most common cause of sudden death.

Adult

[Central type of sleep apnea syndrome caused by unilateral lateral medullary infarction].

We reported here a 64-year-old man with a central apnea resulted from unilateral medullary infarction. He was admitted because of cerebellar ataxia, dysarthria and dysphasia of abrupt onset. After the injection of diazepam for alcohol forbidden syndrome, he induced complete apnea and required the endotracheal intubation. At the spontaneous respiration under room air, his arterial blood gas showed hypercapnea without hypoxemia, and he fell into severe hypoventilation when hypnotic drug was injected. Respisomnogram revealed the frequent presence of central apnea both while he was awake and asleep. MRI demonstrated an abnormal high intensity area on T2 weighted image at the right lateral medulla just below the ponto-medullary junction. At autopsy, areas of the infarction were limited within the right lateral medulla, including lateral portion of the medullary reticular formation, the ambigual nucleus, one part of the solitary nuclear complex, the inferior cerebellar peduncle and the spinal trigeminal nucleus. However, the dorsomotor nucleus of vagus was completely free from the infarct lesion. There was no other lesion within central nervous system. Such a distribution seemed the minimal extent of the lesion responsible for central, apnea compared to the previous reports. We suggest that central apnea occurs not infrequently in the cases of Wallenberg's syndrome.

Cerebellar Ataxia

[Anesthetic management of a neonate with esophageal atresia with double tracheoesophageal fistulae].

We reported the anesthetic management of a 1-day-old female neonate (2,110 gm) with esophageal atresia combined with double tracheoesophageal fistulae, which is classified as Gross type D. Though Gross type C was suspected preoperatively, the proximal fistula was found coincidentally during the preparation of the upper pouch. Because, for one thing, the origin of the proximal fistula was close to the end of the upper pouch (1cm), and for another, the distance between the both fistulae was short (1cm). As for the proximal fistula, it was 2 mm in diameter, and it was easily sealed with the side of the endotracheal tube. No other respiratory managements were needed except frequent suctionings of copious intratracheal secretions. On the other hand, the distal fistula, 10 mm in diameter, caused hypercapnea due to hypoventilation before gastrostomy. It was so big that it is easily intubated. This type of tracheoesophageal fistula is extraordinarily rare and its proximal fistula is difficult to find before, during, and even after operation. The missing of the proximal fistula often provokes severe respiratory infections and furthermore, sepsis postoperatively. It is concluded that in all the cases of tracheoesophageal fistula, the existence of the proximal fistula should be considered without fail and managed accordingly. To diagnose correctly, the use of preoperative bronchofiberscopy is also recommended.

Anesthesia

[Serum catecholamine concentrations and hemodynamics during operations on 23 children with neuroblastoma].

The purpose of the present report is to reveal the relation between hemodynamic changes and serum catecholamine concentrations during operation of 23 neuroblastoma patients. The patients were aged from 6 months to 7 years (mean 1.2 year), and 20 patients (86%) were under 1 year of age. All the patients were in early stage of tumor development because they were diagnosed as neuroblastoma mainly by mass screening test for VMA and HVA in urine utilizing HPLC. This urinary mass screening test for infants is performed routinely in Japan. Operative manipulation of tumor provoked the significant elevation of blood pressure, and the increasing tendency of heart rate and rectal temperature. The mean concentrations of three kinds of serum catecholamine, epinephrine, norepinephrine and dopamine, were all very high during manipulation of tumor. Especially, the norepinephrine concentration was 90.2 times higher than the preoperative value. The children who showed high blood pressure, over 70% of the control level, showed high urinary VMA and VMA/HVA ratio preoperatively and a high norepinephrine secretion during operation. We conclude that for the anesthetic management of neuroblastoma, it is necessary to control the elevation of blood pressure even in small children, especially in the patients who have showed high values of urinary VMA and VMA/HVA ratio preoperatively.

Child

Transformation of the yeast Saccharomyces kluyveri by Saccharomyces cerevisiae-based plasmids.

For the transformation of the yeast Saccharomyces kluyveri, ura3 mutants were obtained by 5-fluoro-orotic acid selection. By utilizing the method based on treatment of intact cells with alkali cations, the ura3 strains of S. kluyveri were transformed by Saccharomyces cerevisiae-based plasmids. In the transformed cells, a S. cerevisiae centromere-based plasmid was stably replicated autonomously. Thus, this system will permit the study of gene expression and its regulation in S. kluyveri in relationship to that in S. cerevisiae.

Ampicillin

Vulnerability of nerve fibres to ischaemia. A quantitative light and electron microscope study.

In order to learn more about the vulnerability of nerve fibres to ischemia, a quantitative study of nerve fibre abnormalities was performed on biopsy specimens of the superficial branch of the peroneal nerve from 26 patients with vasculitic neuropathy: 20 had necrotizing arteritis, 5 a lymphocytic, and 1 a leucocytoclastic vasculitis on nerve and/or muscle biopsy. The density of myelinated fibres ranged from 25 to 7880 per mm2 (n = 8470 +/- 706 (SD]. There was a marked inequality in the density of nerve fibres between the fascicles of individual nerves with a mean coefficient of variation of 41 +/- 37 (SD) % versus 7.4 +/- 3.0% in controls. Loss of myelinated fibres, which was greater for fibres larger than 7 microns in diameter, was more severe than that for unmyelinated axons. Regeneration, which was assessed by the number of clustered axons, decreased when the density of myelinated fibres decreased, suggesting that severe nerve ischaemia precludes axonal regeneration. Wallerian degeneration affected on average 58% (range 5-100%) and segmental demyelination, mainly of the secondary type, on average 1.94% (range 1-10%) of teased fibres. It was concluded that (1) myelinated fibres are more vulnerable to ischaemia than unmyelinated axons; (2) large myelinated fibres are affected before the smaller ones; (3) segmental demyelination is uncommon in this context; (4) severe nerve ischaemia precludes axonal regeneration.

Adult

Marked reduction in CSF lactate and pyruvate levels after CoQ therapy in a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS).

Many CoQ trials for mitochondrial encephalomyopathy are reported, however, the action of CoQ in the central nervous system is unknown. We administered CoQ to a patient with MELAS, and decreasing CSF lactate and pyruvate levels were revealed. This reduction in CSF lactate and pyruvate may be evidence that CoQ acts directly on the CNS. There have been no other descriptions of evidence of CoQ effective action in the central nervous system, a finding unique to this report.

Acidosis, Lactic

Dopaminergic unique affinity of tetrahydroberberine and l-tetrahydroberberine-d-camphor sulfonate.

l-Tetrahydroberberine-d-camphor sulfonate (THB-CS) possessed an inhibitory effect on apomorphine-induced chewing movement in a similar manner to that of tetrahydroberberine (THB). Both compounds enhanced barbiturate-induced hypnosis. They did not have an anticonvulsant effect on convulsive seizures induced by bicuculline, pentetrazole or strychnine. THB and THB-CS blocked dopamine-stimulated adenylate cyclase activity. These compounds showed almost equipotent affinities to dopamine D1 (3H-SCH-23390) and D2 (3H-spiperone) receptors but did not have significant affinity to mu-opioid, muscarinic and alpha 2-adrenergic receptors, and benzodiazepine binding sites. Furthermore, both compounds did not elicit cataleptogenic behavior, even at very high doses. These data suggest that THB and THB-CS have a central depressant effect through both D1 and D2 dopaminergic receptors and may have different modes of action from that of standard neuroleptics.

Animals