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T Atsumi

Publications and source records attributed to T Atsumi.

At least 19 recordsLinked to original sources
PubMed1992

Amiloride at pH 7.0 inhibits the Na(+)-driven flagellar motors of Vibrio alginolyticus but allows cell growth.

Amiloride, a specific inhibitor for the Na(+)-driven flagellar motors of alkalophilic Bacillus, is known to inhibit secondarily the growth of alkalophiles. The motility of a marine Vibrio, V. alginolyticus, was almost completely inhibited by 2 mM amiloride either at pH 7.0 or 8.5. We found that this concentration of amiloride inhibited the cell growth completely at pH 8.5 but only slightly at pH 7.0. Kinetic analysis of the inhibition of motility by amiloride at pH 7.0 showed that the inhibition was competitive with Na+ in the medium. Thus, amiloride at pH 7.0 is really a specific and useful tool for the analysis of the Na(+)-driven flagellar motors of Vibrio.

Amiloride↗
PubMed1992

A novel transthyretin mutation at position 30 (Leu for Val) associated with familial amyloidotic polyneuropathy.

A novel transthyretin (TTR) mutation associated with familial amyloidotic polyneuropathy was detected in a Japanese patient. Single-strand conformation polymorphism analysis and sequence analysis of polymerase chain reaction (PCR)-amplified exons of the patient's TTR gene revealed a point mutation resulting in a substitution of leucine for valine at position 30. As the mutation creates a Cfr13I site, it was confirmed by PCR and restriction analysis. Our finding indicates the importance of position 30 in TTR-derived amyloid fibril formation.

Amyloidosis↗
PubMed1992

Identification of a novel transthyretin variant (Val30----Leu) associated with familial amyloidotic polyneuropathy.

A novel variant transthyretin which contains a leucine-for-valine substitution at position 30 was isolated and identified in the serum of a patient with familial amyloidotic polyneuropathy (FAP). The amino acid substitution was proven to result from a guanine-to-cytosine change at the first base of codon 30 located in exon 2 in the mutated transthyretin gene by restriction fragment length analysis on the amplified transthyretin gene using Cfr13 I. The study indicates that the point mutation of the transthyretin gene is a cause of the disorder.

Amino Acid Sequence↗
PubMed1992

Polar and lateral flagellar motors of marine Vibrio are driven by different ion-motive forces.

Various species of marine Vibrio produce two distinct types of flagella, each adapted for a different type of motility. A single, sheathed polar flagellum is suited for swimming in liquid medium, and numerous unsheathed lateral flagella, which are produced only under viscous conditions, are suited for swarming over viscous surfaces. Both types of flagella are driven by reversible motors embedded in the cytoplasmic membrane. Here we report that the energy source for the polar flagellar motor of Vibrio parahaemolyticus is the sodium-motive force, whereas the lateral flagellar motors are driven by the proton-motive force. This is evidence that two distinct types of flagella powered by different energy sources are functionally active in one cell.

Carbonyl Cyanide m-Chlorophenyl Hydrazone↗
PubMed1992

Regional cerebral blood flow measured with I-123 IMP SPECT in a case of subcortical arteriosclerotic encephalopathy (Binswanger's disease).

N-isopropyl-p-[I-123] iodoamphetamine (I-123 IMP) SPECT studies were performed on a 75-year-old patient who could be clinically classified as subcortical arteriosclerotic encephalopathy (Binswanger's disease). Regional cerebral blood flow (rCBF) was quantitatively measured by a microsphere model, and was diffusely decreased in the whole brain (mean rCBF: 36 ml/100 g/minute). After a ventriculoperitoneal shunt operation, his clinical symptoms were markedly improved, and the improvement was validated by a 32% increase of mean rCBF. However, MRI and CT images showed no significant interval changes before and after the shunt operation. Regional rCBF measurement by I-123 IMP SPECT should be performed and plays an important role in the evaluation of Binswanger's disease.

Aged↗
PubMed1992

P2 purinergic receptors and cellular calcium metabolism in A 431 human epidermoid carcinoma cells.

Stimulation of P2 purinergic receptors on A 431 human epidermoid cells with ATP rapidly mobilized intracellular calcium and increased cytosolic free Ca2+ ([Ca2+]i). Incorporation of 45Ca2+ was also stimulated by ATP at a rate less than that of [Ca2+]i elevation. Among a number of nucleosides, nucleotides, and their analogues examined, ATP, GTP, UTP, ADP, UDP, adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S), and 5'-adenylylimidodiphosphate (AMP-PNP) increased both [Ca2+]i and 45Ca2+ influx, whereas others did not; these latter two analogues (ATP gamma S and AMP-PNP) blocked the ATP-stimulated 45Ca2+ influx only very slightly, suggesting that they are not prominent antagonists but rather agonists. A high correlation between [Ca2+]i increase and 45Ca2+ influx, in terms of nucleotide specificity, suggests the involvement of [Ca2+]i in influx of 45Ca2+. It appeared that [Ca2+]i elevated by several nucleotides or nucleotide analogues opened a calcium gate, thus allowing the influx of 45Ca2+. P2 purinergic receptors on these cells had such a characteristic that they were rapidly desensitized. These nucleotides or analogues also affected epidermal growth factor (EGF) receptors by inhibiting the EGF binding. The differences of ligand or substrate specificities between P2 purinergic receptors and ecto-nucleotidases indicates that the two components are different molecules involved in different systems.

Calcium↗
PubMed1992

[Tumor necrosis factor alpha in systemic lupus erythematosus: evaluation by restriction fragment length polymorphism and production by peripheral blood mononuclear cells].

Human TNF alpha locus locates between HLA-B and DR region on the short arm of chromosome 6. The 5.5 kb and 10.5 kb of TNF alpha restriction fragment length polymorphic (RFLP) bands were identified by Southern hybridization using a restriction enzyme, NcoI. The frequencies of those bands were not different among patients with systemic lupus erythematosus (SLE), those with rheumatoid arthritis and normal controls. In the lupus patients, proteinuria was more frequent in the patients with the 5.5 kb RFLP band (19/39: 48.7%) than those without 5.5 kb band (7/35: 20%) (p less than 0.05). Furthermore, this band was strongly associated with the haplotype HLA B44-DRw13-DQw1. In order to investigate the association between this gene polymorphism and the production of TNF alpha, peripheral blood mononuclear cells from patients with SLE and normal controls were cultured for 24 hours with lipopolysaccharide and concanavalin A and the amount of TNF alpha in the supernatant was measured by enzyme linked immunosorbent assay. The TNF alpha production of lupus patients was not statistically different from that of normal controls. The production of TNF alpha was not related to 5.5 kb RFLP band, but in the patients with SLE, the mean value of TNF alpha in patients with the 5.5 kb RFLP band tended to be higher than those without the band. Lupus patients were divided into two groups by the production of TNF alpha i.e. low TNF alpha inducibility group and high TNF alpha inducibility group. Patients with proteinuria were more frequent in patients of the high TNF alpha inducibility group than those of low TNF alpha inducibility group (p less than 0.05). There were four patients with HLA B44-DRw13-DQw1 who had the 5.5 kb RFLP band and three of them belonged to the high TNF alpha inducibility group with nephrosis. These data suggest that TNF alpha and HLA are possibly associated with the severity of lupus nephritis.

HLA-B Antigens↗
PubMed1992

Role of impairment of blood supply of the femoral head in the pathogenesis of idiopathic osteonecrosis.

To investigate the role of blood supply in the pathogenesis of idiopathic osteonecrosis of the femoral head, superselective angiography of the medial circumflex artery was performed. Sixteen hips with early stage osteonecrosis diagnosed by bone scintigraphy were studied, as were 22 contralateral normal hips (from unilateral cases) and 22 roentgenographically and scintigraphically normal hips in patients who had been administered corticosteroids. All hips demonstrated abnormal superior retinacular arteries in the extraosseous area, and small arteries penetrated 14 hips with early stage osteonecrosis. Abnormal findings were noted in 17 of 22 contralateral normal hips and in 20 of 22 normal hips with corticosteroid administration. Follow-up roentgenographic analysis showed that the hips with small arterial penetration most often developed osteonecrosis. There were two important findings: (1) The blood supply of the superior retinacular arteries from the extraosseous site was impaired. (2) Revascularization was observed not only in hips with early stage osteonecrosis but also in contralateral normal hips and normal hips with corticosteroid therapy. Osteonecrosis is not necessarily a consequence of a single episode of impairment of blood supply of the femoral head but that of a repetitive episode if interruption of revascularization.

Adrenal Cortex Hormones↗
PubMed1992

[A case of systemic lupus erythematosus (SLE) developing pan-dysautonomia].

A 43-year-old woman who had been diagnosed as primary Sjögren's syndrome since 1986 developed severe constipation, urinary retention, dizziness at standing and polyarthralgia in February, 1990. Laboratory tests revealed proteinuria, hypocomplementemia and high titer of anti-DNA antibody. Diagnosis of SLE was made and she was admitted to our hospital on April 2, 1990. Physical examination on admission showed that she also had asymmetric pupils, impairment of sweating, orthostatic hypotension, neurogenic bladder, gastro-intestinal dysmotility and the diminution of R-R interval variability during deep breathing on the electrocardiogram. These findings suggested that she had pan-dysautonomia but there were no signs of motor and sensory disturbance. Because other diseases such as diabetes mellitus and amyloidosis which induced dysautonomia could be ruled out, her pan-dysautonomia seemed to be due to SLE. After the treatment with steroid pulse therapy, most of her dysautonomia improved rapidly. However, some of the disturbance had persisted for a long time. Pan-dysautonomia has been rarely reported as a complication of SLE, and high dose of steroid therapy at the early stage should be considered.

Adult↗
PubMed1992

[Systemic lupus erythematosus associated with benign intracranial hypertension: a case report].

A case of systemic lupus erythematosus (SLE) with benign intracranial hypertension (BIH) is reported. A 41-year-old male with a history of SLE starting in 1982 was admitted to our hospital in December 1989 because of headache and vertigo. Laboratory examinations on admission showed proteinuria, mild anemia, and positive antinuclear and anti-Sm antibodies. No abnormal findings except high pressure of 350 mmH2O were observed in his cerebrospinal fluid (CSF). Fundoscopic examinations showed marked bilateral papilledema and retinal bleeding. Brain CT, MRI and angiography revealed diffuse brain edema without space occupying lesion and cerebrovascular diseases. Because there were no diseases such as endocrinological disorders, severe anemia, and no history of the administration of drugs which might cause intracranial hypertension, the diagnosis of BIH was made. Subsequently, he was treated with intravenous methylprednisolone therapy and osmotic diuretics and his clinical symptoms and pressure of CSF gradually improved. The decrease of CSF adsorption was observed with RI cisternography in our case. Psychosis, seizures and meningitis are common CNS manifestations in SLE patients. But BIH is very rare and its cause is unclear. Only 17 cases of SLE with BIH have been reported. The pathogenesis and treatment of BIH in SLE patients were discussed in this paper.

Adult↗
PubMed1991

Primitive erythropoiesis of mouse teratocarcinoma stem cells PCC3/A/1 in serum-free medium.

Mouse teratocarcinoma stem cells PCC3/A/1 differentiated into various types of cells, such as red cells, when they were grown in serum-free medium containing transferrin and bovine serum albumin on a KCF cell feeder layer. These red cells were stained well with 2,7-diaminofluorene (DAF), and therefore were erythroid cells. They were nucleated and contained embryonic globin chains, immunologically identified with antiembryonic hemoglobin antisera after acid urea Triton X-100 polyacrylamide gel electrophoresis (UT-PAGE). The addition of erythropoietin to the culture medium enhanced the production of both embryonic and adult globin chains. The addition of interleukin-3 also enhanced the production of embryonic globin chains, but not the production of adult globin chains. These results indicated that primitive erythropoiesis of PCC3/A/1 teratocarcinoma cells did not require exogenous addition of any hematopoietic factor such as erythropoietin or interleukin-3. This culture system will be a new model system for investigating the factors regulating the primitive erythropoiesis in yolk sac blood islands.

Animals↗
PubMed1991

[A case of rheumatoid arthritis developing pemphigus-like skin lesion during treatment with bucillamine].

Bucillamine is a useful medication for treatment of rheumatoid arthritis (RA) but some patients develop side effects from it. Here, we report a patient with RA developing a pemphigus-like skin lesion during treatment with bucillamine. A 55 year old woman with RA (stage III, class II) had been treated with bucillamine in our hospital since September 1988. Her symptoms of RA had gradually improved after administration of bucillamine but the generalized skin rash with itching developed in June 1989. Skin biopsy revealed spongiosis, the infiltration of lymphocytes in the epidermis and inter-cellular deposition of IgG. These findings were consistent with the histological change of pemphigus. Since symptoms of the skin disappeared two months later after the discontinuation of bucillamine. We considered that her pemphigus-like lesion was induced by this drug. D-penicillamine is one of the drugs which induce pemphigus. Though the mechanisms of this side effect have not been clear, it is thought that autoantibody induced by D-penicillamine could be one of the cause of pemphigus. Because the chemical structure of bucillamine is similar to that of D-penicillamine, the autoimmune mechanisms may also play a role in the onset of the pemphigus-like lesion in this case.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1991

[Thermography of collagen diseases with Raynaud's phenomenon].

In forty-four patients with collagen diseases accompanied with Raynaud's phenomenon(systemic lupus erythematosus(SLE)10, progressive systemic sclerosis(PSS)15, primary Sjögren's syndrome(PSJS)18 and mixed connective tissue disease(MCTD)1), we analyzed the thermography of fingers after thermal stimulation with cold water(15 degrees C, 30 seconds). In normal controls, the temperature of the distal points of fingers was higher and recovered more quickly than that of the proximal points(proximal interphalangeal joint; PIP). But in the patients with Raynaud's phenomenon, the temperature of distal point of fingers was lower and recovered more slowly than that of proximal points. Because the difference of the temperature between the distal and the proximal points (DP)is a good parameter to distinguish these two thermographic patterns, we analysed DP. DP is less influenced by room temperature than the temperature of fingers and the recovery temperature after thermal stimulation which have been used as indicators of Raynaud's phenomenon. DP in the normal controls was significantly higher than that in the patients. DP in PSS was lower than that in SLE and PSJS, and statistically associated with the markers of disease activities, such as erythrocyte sedimentation rate, titers of anti-RNP antibody and diffusing capacity of lung. These results show that thermographic pattern and the value of DP are the useful indicator of severity of Raynaud's phenomenon.

Adult↗
PubMed1991

[Pneumoperitoneum without perforation of the gastrointestinal tract in a patient with systemic lupus erythematosus].

Pneumoperitoneum often occurs after the perforation of the gastrointestinal tract. However, pneumoperitoneum without the perforation has been reported as one of the complications of collagen diseases, the cause of which is usually the rupture of pneumatosis cystoides intestinalis (PCI). PCI is sometimes observed in the patients with scleroderma and mixed connective tissue disease but rarely in the patients with systemic lupus erythematosus. We reported here a case of systemic lupus erythematosus developed the pneumoperitoneum without the perforation of gastrointestinal tract. A 51-year-old female who had been diagnosed as systemic lupus erythematosus and taken steroid for 12 years, visited our hospital because of general malaise. She had no abdominal symptoms but the roentgenographic examinations revealed the pneumoperitoneum. The laparotomy was performed and there were no findings of the perforation of the gastrointestinal tract. Because PCI is hardly recognized macroscopically after the rupture and the pneumoperitoneum due to PCI is often asymptomatic, we considered the cause of the pneumoperitoneum in this case was the rupture of PCI. The mechanisms of the formation of PCI in patients with collagen diseases were also discussed in this paper.

Female↗
PubMed1979

Adult type neuronal storage disease with neuraminidase deficiency.

We describe a patient with adult-onset neuronal storage disease characterized by myoclonus, cerebellar ataxia, convulsive seizures, cherry-red spots, skeletal dysplasia, mild gargoyle features, inguinal hernia, and angiokeratoma. Cytoplasmic inclusions consistent with lysosomal storage disease were demonstrated in neurons of the autonomic nervous system. Accumulation of GM3 and GM2 gangliosides was found in sympathetic ganglia but a catabolic disturbance of these gangliosides was ruled out by normal levels of GM3 ganglioside sialidase and N-acetyl-beta-hexosaminidase A activities. beta-Galactosidase activity was decreased in leukocytes and fibroblasts, but not in serum. GM1 gangliosidosis was ruled out by lipid analyses, and mucopolysaccharidosis by normal excretion of mucopolysaccharide in urine. Sialyl oligosaccharides were increased in urine and alpha-neuraminidase was deficient in fibroblasts. This disorder is considered to be an inherited metabolic disorder of sialyl glycoproteins and oligosaccharides due to deficiency of an alpha-neuraminidase.

Galactosidases↗
PubMed1979

Retroperitoneal hemangiopericytoma associated with hypoglycemia: report of a case.

A 34-year-old woman had episodes of hypoglycemic attack 8 years after a surgical resection of a retroperitoneal hemangiopericytoma. In spite of normal levels of serum IRI, insulin radioreceptor assay demonstrated high level of plasma ILA (insulin like activity). The patient underwent resection of a recurrent retroperitoneal tumor with metastatic lesions of the liver. Postoperatively, ILA level in plasma by insulin radioreceptor assay decreased, and hypoglycemic attacks disappeared. Therefore, this associated hypoglycemia was presumed to be not caused by excess glucose consumption by the tumor, not by excess secretion of IRI by the tumor, but caused by the presence of high level of ILA related to the tumor.

Adult↗
PubMed1979

A case of Ullrich's disease (Kongenitale, Atonisch-Sklerotische Muskeldystrophie).

An unique myopathy described by Ullrich in 1930 was reported in a 4-year-old Japanese boy. Major clinical findings included proximal joint contracture, muscle hypotonia, prominent calcaneus, high-arched palate, and normal intelli gence. Muscle biopsy showed rather small muscle fivers with variations in size and proliferation of connective tissue. A review of 15 cases in the literature revealed this type of myopathy as a distinctive entity to be classified as a myopathic arthrogryposis multiplex congenita, rather than in the group of muscular dystrophies.

Arthrogryposis↗