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M Tsujihata

Publications and source records attributed to M Tsujihata.

At least 19 recordsLinked to original sources
PubMed2002

Seronegative Lambert-Eaton myasthenic syndrome: study of 110 Japanese patients.

The authors characterized the clinical and immunologic features of 110 patients with Lambert-Eaton myasthenic syndrome (LEMS). Anti-P/Q-type voltage-gated calcium channels (VGCC) antibodies were detected in 85% of the patients (seropositive) but not in the rest (seronegative). Except for the indication that small cell lung carcinoma is less common in seronegative patients, no significant differences were found in the clinical characteristics of patients who had or did not have anti-P/Q-type VGCC antibodies. The results of passive transfer experiments suggest that seronegative LEMS is also an autoantibody-mediated disorder.

Adolescent↗
PubMed2001

A novel role for interleukin-18 in human natural killer cell death: high serum levels and low natural killer cell numbers in patients with systemic autoimmune diseases.

OBJECTIVE: Patients with systemic autoimmune diseases have been reported to have reduced numbers of peripheral blood natural killer (NK) cells compared with healthy subjects. The ability of selected cytokines to trigger NK cell death prompted us to compare the levels of peripheral blood cytokines with the numbers of NK cells in patients with various systemic autoimmune diseases. METHODS: We used enzyme-linked immunosorbent assays to measure the concentration of selected cytokines (interleukin-18 [IL-18], IL-15, IL-12, IL-2, interferon-gamma [IFNgamma], and tumor necrosis factor alpha [TNFalpha]) in sera from 58 patients with systemic autoimmune diseases and 33 healthy controls. The absolute number of T cells and NK cells in the peripheral blood was measured in parallel using flow cytometry. The ability of selected cytokines to induce NK cell death was then measured using 3,3'-dihexyloxacarbocyanine iodide dye, propidium iodide staining, and caspase 3 activity. RESULTS: Levels of IL-18, IL-15, IFNgamma, and TNFalpha were elevated in sera from patients with systemic autoimmune diseases compared with normal controls. The percentage of NK cells and natural killer T cells were significantly decreased in the peripheral blood of patients with systemic autoimmune diseases compared with normal controls. Serum concentrations of IL-18, IL-15, and TNFalpha were inversely related to the number of NK cells in both patients and healthy controls. The combination of IL-18 and IL-15 or IL-18 and IL-12 induced NK cell death in vitro. The combination of IL-18 and IL-15 or IL-18 and IL-12 enhanced IFNgamma and TNFalpha production by NK cells in vitro. Cytokine-induced NK cell death is caspase-dependent and is partially blocked by neutralizing antibodies against TNFalpha. CONCLUSION: High levels of IL-18 and IL-15 are associated with the decreased number of NK cells that is observed in patients with systemic autoimmune diseases.

Adolescent↗
PubMed2001

Strong inhibition of crystal-cell attachment by pediatric urinary macromolecules: a close relationship with high urinary citrate secretion.

OBJECTIVES: To investigate other reasons for the low incidence of pediatric urolithiasis, we evaluated the difference in the crystal-cell adhesion inhibitory activity of urinary macromolecules (UMMs) between children and adults. We also evaluated whether citrates influence the above inhibitory activity, because citrates are important in pediatric urine. METHODS: Urine samples were collected from children and healthy male adults during a 24-hour period, and urinary components with a molecular weight of 3 kDa or greater were extracted as UMMs to compare their inhibitory activity during the adhesion of calcium oxalate monohydrate crystals to cultured Madin-Darby canine kidney cells between children and adults. Subsequently, various concentrations of citrates were added to adult UMMs to evaluate the changes in the crystal-cell adhesion inhibitory activity of UMMs. RESULTS: Pediatric UMMs more strongly inhibited the adhesion of calcium oxalate monohydrate crystals to cultured Madin-Darby canine kidney cells at a concentration of 0.1 mg/mL compared with adult UMMs. In addition, pediatric UMMs contained higher proportions of fibronectin and glycosaminoglycans, both of which exhibit crystal-cell adhesion inhibitory activity. When citrates were added to adult UMMs, the crystal-cell adhesion inhibitory activity of UMMs was increased in a dose-dependent manner. However, citrates alone did not result in any differences in the inhibitory activity at any of the three different concentrations. CONCLUSIONS: We speculate that the incidence of pediatric urolithiasis is low because pediatric UMMs more potently inhibit the adhesion of calcium oxalate crystals to renal tubular cells or because the higher proportion of citrates in pediatric urine enhances the crystal-cell adhesion inhibitory activity of UMMs in a dose-dependent manner.

Adult↗
PubMed2001

Laparoscopic diagnosis and treatment of nonpalpable testis.

OBJECTIVE: Laparoscopy has become one of the important diagnostic modalities of nonpalpable testis and has been developed and applied in the treatment of this disease. In the present study, we investigated the usefulness of laparoscopy in the diagnosis and treatment of nonpalpable testis. METHODS: Laparoscopy was carried out under general anesthesia on 21 patients (23 testes) from October 1991 to October 1999. If the internal spermatic vessels and vas deferens made their way into the internal inguinal ring, the inguinal canal was dissected with an incision in the inguinal region to look for the testis. Patients with intra-abdominal testis underwent laparoscopic orchiopexy or orchiectomy. If the internal spermatic vessels terminated with a blind end intraperitoneally, making it impossible to identify the testis, the case was judged to be vanishing testis and the operation was finalized without any further examination. RESULTS: In eight of 23 testes (35%), the internal spermatic vessels and vas deferens made their way into the internal inguinal ring. The inguinal region was examined in all the eight testes. Orchiopexy was carried out on two testes and orchiectomy was carried out on six testes. An intra-abdominal testis was detected in eight of 23 testes (35%). Laparoscopic orchiopexy was carried out on seven testes. One-stage orchiopexy was carried out on two of the seven testes and two-stage Fowler-Stephens orchiopexy was carried out on five of the seven testes. Orchiectomy was carried out on the remaining testis. Blocking or lack of the internal spermatic vessels and vas deferens was seen in seven of the 23 testes (30%) and this condition was diagnosed as vanishing testis. CONCLUSION: Laparoscopy for nonpalpable testis is considered to be the most effective technique for diagnosing the presence or absence of the testis and the location of the testis.

Adolescent↗
PubMed2001

Comparison of fibronectin content in urinary macromolecules between normal subjects and recurrent stone formers.

OBJECTIVES: Fibronectin (FN: 230 kD) is a multifunctional alpha(2)-glycoprotein distributed throughout the extracellular matrix and body fluids. Recent studies have shown that a variety of molecules, including FN, inhibit the endocytosis of calcium oxalate (CaOx) crystals in vitro. We recently reported that FN was oversecreted from the renal tubular cells as a result of the stimulation of CaOx crystals, and inhibited the aggregation of CaOx crystals and the adhesion of CaOx crystals to the renal tubular cells. In the present study, we investigated the difference of FN content in urinary macromolecules (UMMs) between normal subjects and recurrent stone formers. MATERIALS AND METHODS: Urinary parameters in relation to urolithiasis of normal subjects and recurrent stone formers were measured. Proteins in extracted UMMs from urine of normal subjects and recurrent stone formers were measured with a BioRad protein assay, GAGs in each UMMs with a modified DMB assay and the FN content with the ELISA method. RESULTS: In urinary parameters, citrate was significantly higher in urine from normal subjects (female) than normal subjects (male) or recurrent stone formers, and the other parameters showed no differences between each group. The protein concentrations in UMMs showed no differences between each group. Normal subjects (male and female) showed a significantly higher concentration of GAGs than recurrent stone formers (with and without silent stone). Compared with normal subjects and recurrent stone formers without silent stones, higher FN levels were found in recurrent stone formers with silent stones. Normal subjects showed a significantly higher concentration of FN than recurrent stone formers without silent stones. No difference in FN level was shown between normal subjects (male) and normal subjects (female). CONCLUSION: Recurrent stone formers with silent stones showed a significantly higher concentration of FN in UMMs than normal subjects. This finding suggests that FN might be oversecreted from the renal tubular cells as a result of the stimulation of CaOx stones in vivo. Recurrent stone formers without silent stones showed a significantly lower concentration of FN in UMMs than normal subjects. From this finding it is suggested that FN might play a role as a potent inhibitor of CaOx urolithiasis in a clinical setting.

Adult↗
PubMed2001

Semiquantitative measurement of acetylcholine receptor at the motor end-plate in myasthenia gravis.

OBJECTIVE: The purpose of this study was to investigate whether this semiquantitative measurement of the motor end-plate acetylcholine receptors (AChRs) can be used to confirm the diagnosis of myasthenia gravis (MG), and in particular ocular MG. METHODS: Motor point biopsies were performed from the biceps brachii muscles. Measurement of AChRs was made in peroxidase-labeled alpha-bungarotoxin stained muscle specimens. PATIENTS: Twenty patients with ocular MG, 37 with generalized MG, 5 with Lambert-Eaton myasthenic syndrome, 3 with botulism, 8 with amyotrophic lateral sclerosis, and 8 controls were included in this study. RESULTS: AChRs were decreased in all patients with generalized MG and in 80% of ocular MG including patients without detectable circulating anti-AChR antibodies, as compared with the control subjects. CONCLUSION: This method is useful to confirm the diagnosis of MG, in particular ocular MG without detectable anti-AChR antibodies.

Adolescent↗
PubMed2001

[Undescended testicular tumor found by torsion of the testis: a case report].

A 37-year-old man was admitted with a painful mass in his left inguinal region. He had an undescended testis on the left side. Six months earlier, he had noted that his left inguinal testis was larger, and he had suddenly developed pain in the left inguinal region. The levels of AFP, hCG beta and LDH were normal. We diagnosed a left undescended testicular tumor and torsion of the left testis. Left inguinal high orchiectomy showed a torsion of the left testis and histopathological examination of the specimen revealed seminoma.

Adult↗
PubMed2000

Fibronectin as a potent inhibitor of calcium oxalate urolithiasis.

PURPOSE: Fibronectin (230 kD.) is a multifunctional alpha2-glycoprotein distributed throughout the extracellular matrix and body fluids. Many investigators have demonstrated that fibronectin, because of its cell adhesive action, is related to biological processes such as morphogenesis, wound healing and metastasis. Recent studies have shown that a variety of molecules, including fibronectin, inhibit endocytosis of calcium oxalate crystals in vitro. We investigated other roles of fibronectin in calcium oxalate stone formation. MATERIALS AND METHODS: Immunoblotting of the crystal surface binding substance obtained from pooled healthy male urine samples was used to analyze whether fibronectin was adsorbed onto the surface of calcium oxalate crystals. To clarify the relationship between fibronectin and calcium oxalate crystals, we performed 6 experiments. Experiment 1 was immunohistochemical examination of fibronectin expression in stone forming rat model kidneys, and experiment 2 examined the fibronectin content of stone forming rat kidney models with the enzyme-linked immunosorbent assay. Experiment 3 was designed to determine fibronectin content of Madin-Darby canine kidney (MDCK) cells stimulated by addition of calcium oxalate crystals and experiment 4 identified the inhibitory effect of fibronectin on calcium oxalate crystal growth by the seed crystal method. For experiment 5 we used an aggregometer system to clarify the inhibitory effect of fibronectin on calcium oxalate crystal aggregation and experiment 6 examined the inhibitory effect of fibronectin on the adhesion of calcium oxalate crystals to MDCK cells. RESULTS: In the crystal surface binding substance immunoreactive bands at 230 kD., which correspond to the molecular weight of fibronectin, were detected by Western blot analysis. In stone forming rat kidneys strong expression of fibronectin was found on the renal tubules to which the crystals were attached. The fibronectin content of these kidneys was significantly greater than that of kidneys without calcium oxalate crystals. The fibronectin content of MDCK cells tended to increase in proportion to the concentration of calcium oxalate crystals added to the culture medium. The growth inhibition assay showed that the inhibitory effect of fibronectin on calcium oxalate crystal growth was small in relation to the quantity of fibronectin excreted. However, fibronectin had inhibitory effects on calcium oxalate crystal aggregation and adhesion of the crystals to MDCK cells. CONCLUSIONS: Fibronectin secretion can be stimulated by calcium oxalate crystals, and this protein, which is excreted from the tubular cells, may inhibit calcium oxalate crystal aggregation and attachment to cells.

Animals↗
PubMed1999

Lewy body-type degeneration in cardiac plexus in Parkinson's and incidental Lewy body diseases.

Heart tissues of patients with PD or incidental Lewy body (LB) disease (ILBD) were examined by light and electron microscopy. LBs and alpha-synuclein-positive neurites were identified in the hearts from 9 of 11 patients with PD and from 7 of 7 patients with ILBD. LBs were present in both tyrosine hydroxylase-positive and -negative nerve processes, which are nerves of extrinsic sympathetic and intrinsic origin, respectively. These findings provide histologic evidence that the postganglionic sympathetic and intrinsic neurons in the heart are involved in the PD disease process.

Aged↗
PubMed1999

Bromocriptine protects dopaminergic neurons from levodopa-induced toxicity by stimulating D(2)receptors.

Neuroprotective properties of bromocriptine, a D(2) receptor agonist, were investigated using the in vitro neurotoxicity of levodopa for dopaminergic neurons from rat embryonic ventral mesencephalon. Levodopa, when added to the culture medium, showed toxicity which was specific for dopaminergic neurons. Bromocriptine was found to protect dopaminergic neurons from levodopa toxicity. Another D(2) agonist, 2-(N-phenethyl-N-propyl-amino-5-hydroxytetralin, showed similar protective effects. The neuroprotective effect of bromocriptine was inhibited by supplementation of the culture medium with sulpiride, a D(2) antagonist, or by D(2) receptor knockdown with an antisense oligonucleotide. Dopaminergic neurons treated with levodopa showed an increase in free radicals. These data suggest that neuroprotective properties of bromocriptine seen in this cellular model of neurotoxicity are dependent on dopamine D(2) autoreceptor binding and that levodopa toxicity may be related to increased free radical generation in dopaminergic neurons.

1-Methyl-4-phenylpyridinium↗
PubMed1999

Specificity of omega-conotoxin MVIIC-binding and -blocking calcium channel antibodies in Lambert-Eaton myasthenic syndrome.

An immunoprecipitation assay was used to measure omega-conotoxin MVIIC (P/Q-type) binding and blocking calcium channel antibodies in 67 patients with Lambert-Eaton myasthenic syndrome (LEMS) and in a large control population. We first showed the presence of omega-conotoxin MVIIC-blocking antibody in LEMS patients. Binding antibodies were detected in 55 of 67 (82.1%) LEMS patients and in 2 of 296 (0.7%) controls. In contrast, blocking antibodies were positive in 14 of 67 (20.9%) LEMS patients and 8 of 171 (4.7%) controls. No LEMS patient had negative binding antibodies and positive blocking antibodies. The immunoprecipitation assay detected no antibodies against the whole P/Q-type calcium channel in either the paraneoplastic cerebellar degeneration or the amyotrophic lateral sclerosis sera. Neither the omega-conotoxin MVIIC-binding nor the -blocking calcium channel antibodies were correlated with clinical severity across the individuals, but longitudinal studies of some LEMS patients showed an inverse relation between binding antibody titre and disease severity. We concluded that the 125I-omega-conotoxin MVIIC assay for anti-P/Q-type voltage-gated calcium channel antibodies is highly specific for LEMS and that this sensitive binding antibody assay could be more valuable than the blocking antibody assay in the diagnosis of LEMS.

Antibodies↗
PubMed1999

Possible causes for the low prevalence of pediatric urolithiasis.

OBJECTIVES: To determine why the incidence of pediatric urolithiasis is less than that of adult urolithiasis, we investigated the difference in inhibition of calcium oxalate (CaOX) crystallization between pediatric and adult urinary macromolecules (UMMs). METHODS: Urinary parameters in relation to urolithiasis, the inhibition of CaOX crystallization of original urine and urine from which UMMs (greater than 3 kDa) had been removed, and the inhibition of CaOX crystal growth and aggregation of UMMs alone were measured. These inhibitory activities were compared between children and adults. RESULTS: In the original urine, the inhibition of CaOX crystallization was significantly stronger for children than for adults, but was the same in urine from which the UMMs had been removed. The inhibition of CaOX crystal growth by UMMs alone showed no significant differences between children and adults; their inhibition of CaOX crystal aggregation was significantly stronger for children than for adults. Much more glycosaminoglycan (GAG) was included in pediatric UMMs than in adult UMMs, although there was no difference in UMM concentration between urine from children and urine from adults. CONCLUSIONS: The lower incidence of CaOX lithiasis in children may be attributed, among other factors, to the stronger inhibition of CaOX crystal aggregation by pediatric UMMs, which in turn might be affected by the higher concentration of GAGs in children's urine.

Adolescent↗
PubMed1999

Proteoglycan core protein in human urine and its possible role on calcium oxalate urolithiasis.

BACKGROUND: There are only a few papers reporting on the role of proteoglycan core protein in calcium oxalate stone formation. The present study was carried out to investigate the role of core protein of proteoglycan in human urine on calcium oxalate (CaOx) crystallization. METHODS: Proteoglycans were collected from whole human urine. The covalently bound glycosaminoglycans (GAG) of proteoglycans were then digested by GAG lyase. The inhibitory activity on CaOx crystal growth in vitro was measured before and after enzyme digestion of proteoglycans. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the core protein of proteoglycans and the analysis of amino acid sequence were performed. RESULTS: The core protein showed significant inhibitory activity on CaOx crystal growth, which scarcely changed when compared with that of proteoglycans before enzyme digestion. The SDS-PAGE revealed that the core protein was a single unit with a molecular weight of 26 kDa and amino acid sequencing demonstrated high homology to interalpha-trypsin inhibitor (ITI) light chain (bikunin) with Kunitz inhibitor domain as a core protein. CONCLUSIONS: The results suggested that human urine contains proteoglycans and a major part of them is ITI light chain (bikunin). The Kunitz inhibitor domain, a core protein of bikunin, has significant inhibitory activity on CaOx crystallization without GAG bound covalently to the core protein.

Adult↗
PubMed1999

[Spontaneous peripelvic urine extravasation associated with ileocecal cancer: a case report].

A case of spontaneous peripelvic extravasation with ileocecal cancer is reported. A 60-year-old man with right flank pain was referred to our department. Dripinfusion pyelography showed right peripelvic extravasation. Neither computed tomography (CT) nor retrograde pyelography revealed any ureteral stones or tumors. Urinary cytology was negative. One month later, right retrograde pyelography demonstrated the filling defect in the right ureter, but no stones, ureteral tumors or other tumors related to the ureter were detected by CT. An exploratory laparotomy was done. We found an ileocecal tumor invading to the right ureter and disseminated to the peritoneum. Histological diagnosis was mucinous carcinoma.

Adenocarcinoma, Mucinous↗
PubMed1999

Loss of 123I-MIBG uptake by the heart in Parkinson's disease: assessment of cardiac sympathetic denervation and diagnostic value.

UNLABELLED: Myocardial imaging with 123I-metaiodobenzylguanidine (MIBG) was performed on 35 patients with Parkinson's disease and 24 control subjects to evaluate cardiac sympathetic function in patients with Parkinson's disease, verify this phenomenon and examine whether myocardial MIBG uptake and clearance are correlated with the clinical severity of Parkinson's disease. METHODS: We studied 35 patients with Parkinson's disease and 24 control subjects with other central nervous system diseases. The latter group consisted of 12 subjects with other neurodegenerative disorders (4 with spinocerebellar degeneration, 2 with amyotrophic lateral sclerosis, 3 with progressive supranuclear palsy and 3 with corticobasal degeneration and 12 patients with cerebral infarction (CI), 6 with vascular parkinsonism and 6 without it. Early and delayed images of the anterior view were obtained 15 min and 4 h after injection of 123I-MIBG, respectively. MIBG uptake was quantified by calculating a heart-to-mediastinum count (H/M) ratio. RESULTS: The H/M ratio was markedly reduced in the patients with Parkinson's disease (II to V on the Hoehn and Yahr scale) compared with the control subjects. None of the subjects with neurodegenerative diseases showed a marked decrease in myocardial MIBG uptake nor did any subject with CI. CONCLUSION: Our findings indicate that, in Parkinson's disease, a reduction in myocardial MIBG uptake is a very common, specific phenomenon that can be used to detect cardiac autonomic dysfunction to diagnose Parkinson's disease, particularly in patients without typical signs and symptoms.

3-Iodobenzylguanidine↗
PubMed1997

CAG repeat length and disease duration in Machado-Joseph disease: a new clinical classification.

To evaluate the clinical characteristics of Machado-Joseph disease (MJD) with reference to CAG repeat length and disease duration, we analyzed neurologic findings in 108 patients from 84 families. The majority of MJD patients presented with an ataxic gait as the initial symptom. Dysarthria and nystagmus were observed from an early stage. Bulging eyes, muscle atrophy and bradykinesia developed later. Patients with a shorter CAG repeat length or later onset had more frequent involvement of proprioceptive sensory deficit. Incidence of abnormal reflexes, tones, and proprioceptive sensation was not associated with disease duration, but with CAG repeat length. Based on these results, we propose a new clinical classification: type A (juvenile type), with hyperreflexia and dystonia, but without a proprioceptive sensory deficit; type C (adult type), with hyporeflexia and a proprioceptive sensory deficit, but without dystonia; and type B (intermediate type), the remaining patients with a mixed presentation.

Adult↗