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Biomedical subjects

I Goto

Publications and source records attributed to I Goto.

At least 73 records · Page 4Linked to original sources

Erythrocyte ALA-d activity in experimentally lead-poisoned ducks and its change during treatment with disodium calcium EDTA.

To determine useful procedures for the diagnosis and prognosis of lead poisoning in waterfowl caused by ingestion of lead pellets, erythrocyte delta-aminolevulinic acid dehydratase (ALA-d) was investigated in experimentally lead-poisoned ducks. A highly positive correlation was observed between the concentration of blood lead and the ALA-d activity ratio (the ratio of activated:non-activated enzyme activity) in those birds given seven lead pellets (3 mm diameter). The ALA-d activity ratio rapidly increased after the administration of lead pellets, but began to fall immediately after the initiation of disodium calcium ethylenediamine tetra-acetate (CaEDTA) therapy which resulted in a rapid decrease in the concentration of lead in the blood of these birds. In contrast, the ALA-d activity remained inhibited even after blood lead levels began to decrease following treatment. These results demonstrated that the ALA-d activity ratio is a very useful and sensitive indicator for the diagnosis and evaluation of therapeutic effects after lead poisoning in waterfowl.

Animals↗

Prenatal diagnosis of congenital sialidosis.

A case of prenatally diagnosed congenital sialidosis is described in a 21-week-old male fetus, which was the fifth product of non-consanguineous parents. The proband, the second product, was diagnosed as having sialidosis by the enzyme assay in peripheral leukocytes after birth. At the 17th week of pregnancy, the fetus at risk was proven to have isolated sialidase deficiency after analyzing a sample of the cultured amniotic fluid cells. There were many cytoplasmic vacuoles and increased amounts of sialyloligosaccharides in the tissue of the aborted fetus, while the amount and the pattern of gangliosides in the central nervous system were normal.

Aged↗

A novel response of anion transporter in equine erythrocytes to a fluorescent substrate, N-(2-aminoethyl sulfonate)-7-nitrobenz-2-oxa-3-diazole (NBD-taurine).

This report describes a unique response of the anion transporter in equine erythrocytes to the fluorescent substrate N-(2-aminoethyl sulfonate)-7-nitrobenz-2-oxa-3-diazole (NBD-taurine). Equine erythrocytes showed fluxes of NBD-taurine both inward and outward at rates considerably slower than those in human cells. These fluxes were completely abolished by a typical anion transport inhibitor, 4,4'-diisothiocyanostilbene-2,2'-disulfonate. Furthermore, NBD-taurine competitively inhibited the uptake of phosphate in equine red cells with an inhibition constant of phosphate that was slightly higher than the Michaelis constant of phosphate uptake. These results demonstrate that the anion transporter (band 3) in equine red cells binds NBD-taurine but does not prefer it as the substrate for transport, suggesting a structural difference between equine and human anion transporters at the polypeptide portion which is implicated in anion transport.

Animals↗

Hypertrophic cranial pachymeningitis associated with mixed connective tissue disease; a comparison with idiopathic and infectious pachymeningitis.

This is the first report describing hypertrophic cranial pachymeningitis which developed in association with mixed connective tissue disease (MCTD). A 56-year-old man with a two-year history of MCTD gradually developed symptoms of headache and blurred vision. Bilateral papilledema and increased opening pressure and mild pleocytosis of the cerebrospinal fluid were noted. Magnetic resonance imaging of the brain revealed a diffuse thickening and a gadolinium-enhancement of the cranial dura mater. While five previous patients, diagnosed as idiopathic or infectious hypertrophic cranial pachymeningitis in our department, had either otitis media or sinusitis and showed multiple cranial nerve involvement, the present patient had neither otitis media nor sinusitis and did not show any cranial nerve involvement other than papilledema.

Adult↗

Accumulation of abnormal prion protein in mice infected with Creutzfeldt-Jakob disease via intraperitoneal route: a sequential study.

We immunohistochemically studied the location of abnormal prion protein in the central nervous system and visceral organs at the clinical and preclinical stages of mice infected with Creutzfeldt-Jakob disease via intraperitoneal route. Abnormal prion protein was diffusely distributed in the central nervous system. The sequential study showed that its stainings were first detected 120 days after inoculation, were found in all mice after 180 days, and were the most intense and widespread after 270 days. There was no restricted involvement at the early stages nor rostrally dominant distribution of the stainings that had been found in mice infected via intracerebral route. Abnormal prion protein was also located in the follicular dendritic cells in the spleen, lymph nodes, intestinal Peyer's patch, and thymus. Its stainings were first detected in the spleen, lymph nodes, and Peyer's patch 14 or 30 days after inoculation. In the thymus, however, the stainings were first detected after 210 days in the germinal centers formed in the medulla.

Animals↗

[Hallervorden-Spatz disease].

Hallervorden-Spatz disease is an autosomal recessive disorder which usually begins in childhood, progresses irreversibly and leads to death in early adulthood. The main manifestations are extrapyramidal signs, such as, dystonia and rigidity, pyramidal signs and mental deterioration. Pathological changes are found mainly in globus pallidus. They are characterized by (1) pigmentation with iron, and (2) numerous spheroids which represent abnormal axonal swelling. The cause of the disease is not clear but excessive iron storage may contribute to pathogenesis. The patients are treated symptomatically. The definite diagnosis is difficult and is made post mortem. Recently, however, characteristic MRI findings has been reported, which may be useful for the diagnosis during life.

Genes, Recessive↗

[Lesion of the bilateral MLF and unilateral paramedian pontine reticular formation, caused by an infarction in the midbrain tegmentum].

A 71-year-old man with bilateral medial longitudinal fasciculus (MLF) syndrome and paralytic pontine exotropia caused by an infarction of the midbrain tegmentum was reported. He suddenly noticed a diplopia and gait disturbance, and visited our clinic. Neurological examination revealed that this right eye was slightly abducted in the primary position. On horizontal gaze, outwardbeating nystagmus of the abducted eyes was observed, bilaterally. The adduction of the bilateral eyes was severely disturbed and the abduction of the left eye was slightly restricted, while the convergence was normal. T2-weighted magnetic resonance imaging revealed high signal intensity area in the medial portion of the midbrain tegmentum, which indicated an infarction. Several cases showing bilateral MLF syndrome with exotropia have been reported, but a case whose lesion was shown in the midbrain has not been reported so far. The present case suggests that paramedian pontine reticular formation (PPRF) is not confined to pons but expands to midbrain.

Aged↗

[A family with MELAS whose main manifestations are maternally-transmitted deafness and diabetes mellitus].

A family with maternally-transmitted deafness and diabetes mellitus is described. Although the proband clinically exhibited MELAS-like symptoms such as sudden-onset cerebellar ataxia and weakness of the proximal portion of the limbs in addition to deafness and diabetes mellitus, the other three members of the family had only deafness and diabetes mellitus and no neurological manifestations. The analysis of mitochondrial DNA of the two members revealed an A-->G mutation of tRNA(leu(UUR)), a mutation commonly seen in patients with MELAS. According to the clinical histories and endocrinological investigations, the type of the diabetes mellitus in this family was considered to be IDDM, which may be attributed to the dysfunction of mitochondrial of the pancreas islet cells, resulting from the mutation of the mitochondrial DNA.

Adult↗

Relation between reduced glutathione content and Heinz body formation in sheep erythrocytes.

To clarify the oxidant defense functions of reduced glutathione (GSH) in erythrocytes, the effect of GSH deficiency on in vitro oxidant defense was studied, using GSH-deficient sheep erythrocytes (low-GSH cells). The formation of Heinz bodies in low-GSH cells was higher than that in high-GSH cells when the cells were incubated with an oxidant drug, acetylphenylhydrazine (APH). Artificial depletion of GSH by 1-chloro-2,4-dinitrobenzene in high-GSH cells resulted in increased Heinz body formation in these cells incubated with APH. Furthermore, high negative correlation was observed between Heinz body formation and GSH content in sheep erythrocytes exposed to APH. These results clearly indicate that erythrocyte GSH is indispensable for erythrocyte defense against oxidative damage induced by APH, and support the previous observations that sheep with low-GSH erythrocytes were more susceptible to oxidative agents than were sheep with high-GSH erythrocytes.

Animals↗

Successful transmission of Creutzfeldt-Jakob disease from human to mouse verified by prion protein accumulation in mouse brains.

The accumulation of prion protein (PrP) was revealed in the brains of mice inoculated with the brain homogenate from seven patients with Creutzfeldt-Jakob disease (CJD) by immunohistochemistry using hydrolytic autoclaving. It was not found in the brains of mice inoculated with material from either two patients with Gerstmann-Sträussler syndrome or two with other dementing illnesses. PrP accumulation took the forms of diffuse neuropil accumulation in the gray matter and plaque-like accumulation in the white matter and was observed in particular areas in the supratentorial structure. Its distribution was narrower than that in the brains of mice infected with a mouse-adapted CJD strain. PrP accumulation was found not only in all histopathologically positive mice, but also in some histopathologically negative mice. In all groups of mice inoculated with the material from each CJD patient, the percentage of mice with PrP accumulation was equal to or exceeded that of mice with the histopathological findings. PrP immunohistochemistry using formic acid pretreatment stained such plaque-like accumulation less intensely than that using hydrolytic autoclaving and did not stain diffuse neuropil accumulation. Therefore, PrP accumulation which can be revealed in the brains of first-passage CJD mice by this new immunohistochemical method may be the most sensitive hallmark of successful transmission.

Animals↗

Treatment of lead poisoning in wild geese.

Twenty-seven wild geese (Anser albifrons) suffering from lead poisoning caused by ingestion of lead shot were treated with disodium calcium ethylenediaminetetraacetate. The concentration of lead in blood ranged from 0.4 to 23.0 micrograms/ml, with a mean concentration of 5.6 micrograms/ml. In 22 of the birds, 1 to 48 lead pellets (mean, 10.5 pellets/bird) were seen on radiographs of their gizzards. Eleven of 27 birds recovered 3 to 8 weeks after the initiation of treatment. In the birds that recovered, the lead pellets were rapidly eroded as the birds recovered their appetites in response to treatment, and disappeared radiographically between treatment days 17 and 52. The birds that did not survive died within 4 weeks, despite decreased concentrations of lead in blood. Of these 16 birds, 15 had radiographic evidence of impaction of the proventriculus at the first examination and no evidence of resolution of the impaction at the time of death. In contrast, only 2 of the 11 geese that recovered had impaction of the proventriculus at the time of admission. Thus, the condition of the proventriculus seems to be the first consideration to evaluate in the prognosis of lead poisoning in geese.

Animals↗

Glutaminase and glutamine synthetase activities in human cirrhotic liver and hepatocellular carcinoma.

Glutamine synthetase and glutaminase activities in human cirrhotic liver tissues and hepatocellular carcinomas were determined for comparison with normal liver tissues. In hepatocellular carcinoma, glutamine synthetase activity was approximately one-third of that in normal liver, whereas no detectable change in the enzyme activity was observed in cirrhotic liver. Phosphate-dependent and phosphate-independent glutaminase activities were increased approximately 20-fold and 6-fold, respectively, both in the carcinoma and cirrhotic liver compared with those from normal liver, Oxypolarographic tests showed that the rate of glutamine oxidation in the tumor and cirrhotic liver mitochondria was about 5-fold higher than that in the liver mitochondria. The rate of glutamate oxidation in the liver mitochondria was comparable to that in the cirrhotic liver and tumor mitochondria. Glutamine oxidation was inhibited by prior incubation of the mitochondria with 6-diazo-5-oxo-L-norleucine, which inhibited mitochondrial glutaminase. These results indicate that the product of glutamine hydrolysis, glutamate, is catabolized in the tumor and cirrhotic liver mitochondria to supply ATP. In the liver and cirrhotic liver mitochondria, glutamate was oxidized via the routes of transamination and deamination. On the other hand, glutamate oxidation was initiated preferentially via a transamination pathway in the tumor mitochondria.

Carcinoma, Hepatocellular↗

Influence of food on serum ambenonium concentration in patients with myasthenia gravis.

Influence of food on the serum concentration and kinetics ambenonium chloride (AMBC) has been examined in thirteen patients with myasthenia gravis (MG). Mean serum concentrations and Cmax during fasting were higher than those in the non-fasting state. The AUC (0-3 h) was also about four-times larger. The drug effects versus the serum concentration were observed to be anti-clockwise or clockwise. The effective range of the Cmax varied between patients. The unexpected increase in Cmax led to adverse muscarinic actions of AMBC, when the condition was changed from the nonfasting to the fasting state. It is recommended that the dose be changed during non-fasting treatment when adjusting the optimum regimen for patients myasthenia gravis. Patients must be advised to keep to the dosing and dietary schedule in order to avoid unexpected adverse actions to AMBC.

Adult↗

Protein kinase C in rat brain myelin.

It has been suggested that phosphorylation of myelin basic protein (MBP) in CNS is catalyzed by protein kinase C (PKC). In order to demonstrate that PKC in the myelin phosphorylates MBP, PKC was partially purified from rat CNS myelin by solubilization with Triton X-100 followed by a DEAE-cellulose column. MBP and histone III-S were phosphorylated in the presence of Ca2+ and phospholipid by rat myelin PKC. High voltage electrophoresis revealed that the phosphoamino acids in MBP by this kinase was serine residue, which is known to be the amino acid phosphorylated by PKC. The activity of PKC extracted from myelin was inhibited by the addition of psychosine to the incubation mixture. To confirm the presence of PKC molecule and to identify the isoform of PKC in the myelin, the solubilized myelin fraction was applied on SDS-PAGE, transferred to a nitrocellulose sheet and stained with anti-PKC monoclonal antibodies. Rat CNS myelin contained the PKC of about 80 kDa (intact PKC), and no proteolytic fragments were observed. PKC isozymes in myelin were type II and III. A developmental study from 14 to 42 postnatal days showed that PKC activity in CNS myelin seemed to parallel the deposition of myelin protein.

Animals↗

Regional cerebral glucose metabolism in patients with Parkinson's disease with or without dementia.

By means of positron emission tomography, the cerebral glucose metabolism in 5 patients with Parkinson's disease with dementia was compared with that in 9 patients without dementia, and that in 5 normal volunteers. The metabolic rates for glucose were measured by placing one hundred regions of interest. In the demented patients, cerebral glucose metabolism was diffusely decreased compared with that of the non-demented patients and the normal controls. The most significant decrease in glucose metabolism was observed in the angular gyrus (49.7% of the normal controls). The glucose metabolism in the cingulate, pre- and postcentral, occipital and subcortical regions was relatively spared (62.1 to 85.5% of the normal controls). In the patients without dementia, the glucose metabolism in each region was not significantly different from that in the normal controls. These results suggest that diffuse glucose hypometabolism in the cerebral cortex may correlate with that of patients with Parkinson's disease with dementia.

Aged↗

Increased striatal 18F-dopa uptake and normal glucose metabolism in idiopathic dystonia syndrome.

Striatal 18F-Dopa uptake and glucose metabolism were studied by positron emission tomography with 6-L-[18F]fluorodopa and [18F]fluorodeoxyglucose, respectively, in 8 patients with idiopathic dystonia. Patients with abnormal findings on the brain CT and MRI were excluded from this study. The clinical diagnosis consisted of torsion dystonia in 3 patients, focal dystonia limited in the arm in 3 and cervical dystonia (spasmodic torticollis) in 2. The 18F-Dopa uptake, corrected by nonspecific retention in the cerebellum, at 120 min post-administration was evaluated, and increased 18F-Dopa uptake in the putamen and in the caudate head was observed in the patients with idiopathic dystonia compared to the normal controls. The striatal glucose metabolism in the patients with idiopathic dystonia showed no difference with the normal controls. These findings suggest that pathogenetic mechanism of idiopathic dystonia involves increased presynaptic activity of the dopaminergic system in the striatum.

Adult↗

Enhanced proliferative response of myasthenic thymus cells in mixed lymphocyte reaction.

To determine the functional diversity of thymic lymphoid cells in patients with myasthenia gravis (MG), we evaluated mixed lymphocyte reactions (MLR) using thymus cells in 7 MG patients and 8 controls. In the MLR, we used thymus cells as responder cells and mitomycin C-treated peripheral non-T cells as stimulator cells. In an autologous MLR test, a low proliferative response was observed in both the MG patients and controls. In an allogeneic MLR test, in which thymus cells were co-cultured with allogeneic non-T cells, the thymus cells from MG patients showed an increased proliferative response to stimulator cells, whether they were from MG patients or the controls. However, thymus cells from the controls showed a low proliferative response to any allogeneic stimulator cells. The enhanced allo-reactivity of thymus cells from MG patients thus suggests that there is an increase in the number of functionally mature T lineage cells in the MG thymus.

Adolescent↗