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Shu-Ichi Ikeda

Publications and source records attributed to Shu-Ichi Ikeda.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of the histological and immunohistochemical features of the thymus in young- and elderly-onset myasthenia gravis without thymoma.

We performed histological and immunohistochemical analyses of the removed thymuses from 20 elderly (onset age > 60 years) and 23 young (onset age < 40 years) patients with myasthenia gravis (MG) who tested positive for serum anti-acetylcholine receptor (AChR) antibodies, but who did not have associated thymoma. In the elderly group, nine (45%) patients had accumulations of lymphocytes, indicating an atrophied thymus with loss of the basic structure. The elderly MG patients with atrophied thymic tissues had higher titres of anti-AChR antibody (59.6+/-81.0 nmol/L) than those with adipose infiltration of the thymus alone (20.1+/-20.9 nmol/L). In immunohistochemical studies using image analysis, both young patients and elderly patients with atrophied thymic tissues were found to have significantly higher levels of CD20 than age-matched controls (p < 0.005). Atrophied thymic tissues, often seen immunohistochemically in young MG patients, may also be found in elderly patients, particularly in those with high titres of the anti-AChR antibody, even though adipose infiltration is marked in these patients.

Adolescent↗
PubMed2006

A Japanese case of SCA14 with the Gly128Asp mutation.

Spinocerebellar ataxia type 14 (SCA14) is a rare form of autosomal dominant cerebellar ataxias caused by mutations in the protein kinase Cgamma gene (PRKCG). We have identified a Japanese patient with SCA14 who carried the Gly128Asp mutation in PRKCG. She first noticed gait unsteadiness at around age 42, and then her gait ataxia worsened very slowly for more than 20 years. At age 62, she was still ambulatory, although cerebellar ataxia was clinically evident. She is the second patient identified with the G128D mutation. Both patients with this mutation showed pure cerebellar ataxia. With only two families with SCA14 found in Japan prior to this study, the clinical features and disease-causing mutations in PRKCG are heterogeneous in the same ethnic background.

Adult↗
PubMed2006

A -16C>T substitution in the 5' UTR of the puratrophin-1 gene is prevalent in autosomal dominant cerebellar ataxia in Nagano.

The molecular bases of autosomal dominant cerebellar ataxia (ADCA) have been increasingly elucidated, but 17-50% of ADCA families still remain genetically undefined in Japan. In this study we investigated 67 genetically undefined ADCA families from the Nagano prefecture, and found that 63 patients from 51 families possessed the -16C>T change in the puratrophin-1 gene, which was recently found to be pathogenic for 16q22-linked ADCA. Most patients shared a common haplotype around the puratrophin-1 gene. All patients with the -16C>T change had pure cerebellar ataxia with middle-aged or later onset. Only one patient in a large, -16C>T positive family did not have this change, but still shared a narrowed haplotype with, and was clinically indistinguishable from, the other affected family members. In Nagano, 16q22-linked ADCA appears to be much more prevalent than either SCA6 or dentatorubral-pallidoluysian atrophy (DRPLA), and may explain the high frequency of spinocerebellar ataxia.

5' Untranslated Regions↗
PubMed2006

Dystonia, mental deterioration, and dyschromatosis symmetrica hereditaria in a family with ADAR1 mutation.

A family with dystonia associated with dyschromatosis symmetrica hereditaria (DSH), mental deterioration, and tissue calcification is described. The proband possessed an adenosine deaminase acting on the RNA 1 gene (ADAR1) mutation Gly1007Arg. This ADAR1 mutation could disturb RNA editing at Q/R sites of glutamate receptor in the brain and increase Ca(2+) influx into neurons, which is thought to induce dystonia and mental deterioration. The observations in our family raise the possibility that the ADAR1 mutation might be a direct cause or a predisposing factor for heredodegenerative dystonia. Further investigation of ADAR1 mutations will shed light on the genotype-phenotype correlation in DSH.

Adenosine Deaminase↗
PubMed2006

Value of renal biopsy in the prognosis of liver transplantation in familial amyloid polyneuropathy ATTR Val30Met patients.

Liver transplantation for familial amyloid polyneuropathy (FAP) patients has been carried out worldwide and the outcomes seem to be promising. To clarify the severity of amyloid deposits on visceral organs, we evaluated the histopathological findings of biopsied renal and sural nerve specimens in 13 FAP patients with ATTR Val30Met by quantitative analysis, and compared them with the outcome of transplantation. Renal dysfunction with proteinuria seemed to correlate with the degree of amyloid deposits in glomeruli, not with that in medullary tissues. The severity of renal amyloid deposition did not consistently parallel that of myelinated nerve fiber loss in sural nerve. Three patients with proteinuria and severe amyloid deposits in glomeruli were considered to be unsuitable for transplantation. Ten patients underwent living donor liver transplantation and three resulted in unfavorable outcomes. These three had heavy amyloid deposits on renal tissues, especially in glomerular areas, but the severity of myelinated nerve fiber loss in their sural nerves was very similar to that in patients who made a good recovery. The prognosis after operation might be closely related to the severity of amyloid deposits in renal glomeruli. Renal biopsy is, therefore, recommended when determining the indications and contraindications for liver transplantation in FAP patients, although this biopsy is not routinely required.

Adult↗
PubMed2006

Histopathological regression of systemic AA amyloidosis after surgical treatment of a localized Castleman's disease.

Previously, we reported a case of localized plasma cell type Castleman's disease with severe hepatomegaly and reactive systemic AA amyloidosis. The amyloid deposits were demonstrated in both the hepatic tissue and in the gastric mucosa. Surgical resection of an isolated extra-hepatic tumor was performed. The laboratory findings, including SAA and IL-6, remained within normal limits and the patient's hepatomegaly subsequently showed regression. Nine years after the operation, no amyloid deposition was seen in the gastric mucosa and the patient's liver was of normal size. Our findings with long-term follow up in this case indicated that the cessation of SAA production was the probable cause of histopathological regression of AA amyloid deposits in this patient.

Adult↗
PubMed2005

Metabolic derangements in deficiency of citrin, a liver-type mitochondrial aspartate-glutamate carrier.

Citrin, encoded by SLC25A13, is a liver-type mitochondrial aspartate-glutamate carrier (AGC), of which deficiency, in autosomal recessive trait, causes neonatal intrahepatic cholestasis (NICCD) and adult-onset type II citrullinemia (CTLN2). NICCD patients have jaundice, hypoproteinemia, hypoglycemia, galactosemia, growth retardation, fatty liver and multiple aminoacidemia including citrulline, methionine, threonine and tyrosine. Some of the neonates who have experienced NICCD suffer from severe CTLN2 more than 10 years or several decades later. In CTLN2, neuropsychotic symptoms such as disorientation, aberrant behavior, coma and death are observed. Laboratory findings reveal hyperammonemia, citrullinemia, fatty liver and liver-specific decrease in a urea cycle enzyme, argininosuccinate synthetase (ASS). In some cases, hyperlipidemia, pancreatitis and hepatoma are accompanied with CTLN2. Citrin as a liver-type AGC plays a role in supplying aspartate to the cytosol for urea, protein and nucleotide synthesis by exchanging mitochondrial aspartate for cytosolic glutamate and proton, and transporting cytosolic NADH reducing equivalent to mitochondria as a member of malate aspartate shuttle essential for aerobic glycolysis. AGC is also important for gluconeogenesis from lactate. Although it is difficult to explain pathogenesis of the symptoms such as cholestasis in NICCD and liver-specific decrease of ASS protein in CTLN2 from the functions of the AGC, some are understandable by the loss of citrin functions. Many CTLN2 patients have been treated with a low protein and high carbohydrate diet and glycerol at the hyperammonemic coma. We argue that those treatments may result in fatty liver, hyperlipidemia, hyperammonemia and even death due to loss of the citrin functions. Loss of citrin first cause deficiency of aspartate in the cytosol, which results in an increase in cytosolic NADH/NAD(+) ratio and then activation of fatty acid synthesis pathway to compensate the aberrant ratio. This follows inhibition of fatty acid oxidation. The peculiar fondness for food of CTLN2 patients who like protein and dislike carbohydrate and sweets may be related to their metabolic requirements.

Journal Article↗
PubMed2005

Comparison of the strain Doppler echocardiographic features of familial amyloid polyneuropathy (FAP) and light-chain amyloidosis.

Previous work has demonstrated that familial amyloid polyneuropathy (FAP) and light-chain amyloidosis with similar degrees of cardiac involvement cannot be distinguished by standard echocardiographic parameters, yet the severity of congestive heart failure and cardiac mortality is much less in FAP. It was therefore hypothesized that strain and strain-rate imaging, sensitive markers of longitudinal systolic dysfunction, might detect a difference in left ventricular function between FAP and light-chain amyloidosis that could account for the clinical differences.

Amyloid Neuropathies, Familial↗
PubMed2005

Chronic inflammatory demyelinating polyradiculoneuropathy with autonomic involvement.

We report a case of chronic acquired neuropathy predominantly affecting sensory and autonomic nerves. Investigations showed a demyelinating polyradiculoneuropathy with axonal degeneration and depletion of postganglionic noradrenergic fibers in the rectal mucosa. Intravenous immunoglobulin and corticosteroid administration were effective in alleviating symptoms and improving electrophysiological abnormalities. This neuropathy may be a novel variant of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), in which autoimmunoreactivity is directed not only against myelin but also against axon- or ganglion-composing protein. Autonomic nerve involvement does not exclude a diagnosis of CIDP.

Autonomic Nervous System Diseases↗
PubMed2005

Correlation between serum levels of free light chain and phenotype of plasma cells in bone marrow in primary AL amyloidosis.

To investigate whether there is a correlation between subtypes of plasma cells in the bone marrow and the production of M-protein, flow cytometry and serum free light chain (FLC) analyses were carried out in 17 patients with primary systemic AL amyloidosis (mean age, 59.9+/-8.8 years) and controls with M-protein (MGUS controls, n=6) and without it (negative controls, n=9). The patients showed a significantly higher value in the serum predominant FLC:serum creatinine ratio (43.8+/-63.2) and CD38++ CD19- CD56+ subpopulation (monoclonal plasma cells) (2.57+/-5.35%) than either the negative (p<0.0005 and p<0.001, respectively) or MGUS controls (p<0.05). With respect to maturation of plasma cells in the bone marrow, the intermediate (MPC-1+ CD45- CD49e-) and mature (MPC-1+ CD45+ CD49e-) subtypes were significantly higher (49.2+/-23.2%, p<0.005) and lower (27.6+/-21.3%, p<0.005) in the patients than in the negative controls, respectively. The serum predominant FLC:serum creatinine ratio was elevated in parallel with an increase in CD38++ CD19- CD56+ and MPC-1+ CD45- CD49e- cells and a decrease in mature subtypes (MPC-1+ CD45+ CD49e- and MPC-1+ CD45+ CD49e+ cells), There was a significantly positive correlation between the serum predominant FLC:serum creatinine ratio and either CD38++ CD19- CD56+ (r=0.510, p<0.05) or MPC-1+ CD45- CD49e- cells (r=0.481, p<0.05). In primary AL amyloidosis M-protein is probably produced by increased monoclonal plasma cells in the bone marrow, particularly by the intermediate subpopulation with a phenotype of MPC-1+ CD45- CD49e-.

Adult↗
PubMed2005

Amyloid: toward terminology clarification. Report from the Nomenclature Committee of the International Society of Amyloidosis.

The modern nomenclature of amyloidosis now includes 25 human and 8 animal fibril proteins. To be included in the list, the protein has to be a major fibril protein in extracellular deposits, which have the characteristics of amyloid, including affinity for Congo red with resulting green birefringence. Synthetic fibrils with amyloid properties are best named 'amyloid-like'. With increasing knowledge, however, the borders between different protein aggregates tend to become less sharp.

Amyloid↗
PubMed2005

Severe protein losing enteropathy with intractable diarrhea due to systemic AA amyloidosis, successfully treated with corticosteroid and octreotide.

This report concerns two patients with severe protein losing enteropathy and refractory diarrhea due to AA amyloidosis who were successfully treated with corticosteroid and octreotide. In these patients, biopsied tissues from the gastrointestinal (GI) tract showed extensive deposition of AA amyloid, which was caused by rheumatoid arthritis in one case and was of unidentified etiology in the other. Both patients manifested severe diarrhea unresponsive to conventional treatment with hypoproteinemia, and protein leakage from the small intestine to the ascending colon was confirmed by 99mTc-diethylene triamine pentaacetic acid human serum albumin (HSA-D) scintigraphy. Soon after starting a long-acting somatostatin analogue, octreotide, with co-administration of oral prednisolone, their general status improved in parallel with a rapid decrease in the volume of watery diarrhea and an increase in serum levels of albumin and IgG. Also on 99mTc-HSA-D scintigraphy protein leakage from the GI tract was apparently decreased in both patients. Combination therapy with a somatostatin analogue and corticosteroid may be effective for protein losing enteropathy with intractable diarrhea ascribable to GI amyloidosis. Because of the lack of specific therapies in this serious clinical situation, the described therapy should actively be considered as a therapeutic option not only in AA amyloidosis, but also in other types of systemic amyloidosis.

Adrenal Cortex Hormones↗
PubMed2005

Unexpectedly high incidence of visceral AA-amyloidosis in slaughtered cattle in Japan.

Experimental mouse AA amyloidosis can be transmissible by dietary ingestion of amyloid fibrils and it is well known that AA amyloidosis occasionally develops in aged cattle. Bovine liver and intestine have conventionally been used in Oriental foods, and the incidence of visceral AA amyloidosis in slaughtered cattle was evaluated. Renal tissues from 302 aged cattle older than 4 years were obtained from a local abattoir. Amyloid deposition was microscopically examined and amyloid protein was immunochemically determined. Renal amyloid deposition was seen in 15 out of 302 cattle with no previous history of diseas, an incidence of 5.0%. Amyloid protein in these cattle was AA and they had pathological findings in their visceral organs on gross examination. The incidence of visceral AA amyloidosis in slaughtered cattle in this study was disturbingly high compared with those (0.4-2.7%) previously reported from Japan and other foreign countries. AA amyloidosis is a life-threatening complication in patients with chronic inflammatory diseases and these patients at risk should avoid ingesting food that may possibly contain AA amyloid fibrils. More detailed information on cattle amyloidosis is required to guarantee the safety of our food.

Amino Acid Sequence↗
PubMed2005

Biochemical characteristics of variant transthyretins causing hereditary leptomeningeal amyloidosis.

Transthyretin (TTR) is a tetrameric protein that can dissociate into amyloidogenic monomers and cause TTR-related amyloidosis. A rare phenotype, called hereditary leptomeningeal TTR amyloidosis, in which TTR amyloid deposition occurs mainly in leptomeninges and subarachnoid vessels, has been reported in patients with several different TTR variants. In the present study, we examined TTR variants immunoprecipitated from the serum and cerebrospinal fluid (CSF) of patients with hereditary leptomeningeal TTR amyloidosis using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (IP-Mass method). The leptomeningeal-type TTR variants were not detected in the serum but were found at low levels in the CSF. The undetectable levels of the leptomeningeal-type TTR variants in serum could explain the minute amounts of systemic deposition of these variants. The relatively high level of unstable TTR variants in CSF, probably due to increased secretion from the choroid plexus, is considered to be the pathogenesis of the leptomeningeal-type of TTR amyloidosis.

Adult↗
PubMed2005

Prevalence and clinical features of cough variant asthma in a general internal medicine outpatient clinic in Japan.

OBJECTIVE: The aims of the present study were to examine the prevalence and clinical features of cough variant asthma (CVA) among patients with chronic and persistent cough at an outpatient clinic in Japan, and the efficacy of treatment with an inhaled corticosteroid. METHODOLOGY: This prospective study was conducted at a general internal medicine outpatient clinic in Japan over a 12-month period. CVA was diagnosed as chronic cough without wheezing or any apparent cause, that had persisted for more than 8 weeks, with a normal CXR and spirometry but with bronchial hyperresponsiveness to methacholine, and relief of cough after bronchodilator treatment. We also examined the effects of inhaled beclomethasone propionate on symptoms and differences in PEF between early morning and evening. RESULTS: Of 55 patients suffering from chronic cough, 23 satisfied the criteria for CVA. Their cough occurred more frequently at night and early in the morning. Early morning PEF was significantly lower than evening PEF with a mean variability of 11.5 +/- 4.1%. Treatment with beclomethasone propionate improved coughing and significantly increased early morning PEF, reducing variability to less than 10%. CONCLUSIONS: These findings suggest that CVA is most common among patients with chronic cough not due to any apparent cause. The efficacy of inhaled corticosteroid suggests that early intervention is effective in the treatment of CVA.

Administration, Inhalation↗
PubMed2005

Serum amyloid A as a potent therapeutic marker in a refractory patient with polymyalgia rheumatica.

We report a patient with polymyalgia rheumatica (PMR) who showed a relapse soon after tapering of oral prednisolone. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were quickly normalized after the re-increase in oral prednisolone, and muscle pain and stiffness gradually improved in parallel with a decrease in serum amyloid A (SAA). Flow cytometry simultaneously demonstrated an increase in CD8+CD25+ cells and a decrease in CD4+CD25+ cells and CD4+CD45RA+ cells. When clinical symptoms remain with negative results for CRP and ESR even after the start of corticosteroid treatment, SAA might be a potent therapeutic marker for disease activity in PMR.

Aged↗
PubMed2005

Ten years of experience with liver transplantation for familial amyloid polyneuropathy in Japan: outcomes of living donor liver transplantations.

OBJECTIVE: We summarize 10 years of experience with liver transplantation for FAP patients in Japan and review the current opinions regarding this treatment for FAP. METHODS AND PATIENTS: All basic report data on patients at the time of transplantation were registered with the Japanese Liver Transplantation Society (JLTS). Based on the JLST report data, more detailed information on FAP patients was requested from each center. RESULTS: Living donor liver transplantation (LDLT) for FAP patients was first performed in Japan in 1993. LDLT has since been performed in 41 FAP patients, including nine cases of temporary auxiliary partial orthotopic liver transplantation (APOLT). Orthotopic liver transplantation (OLT) from cadaveric donors for FAP patients began in 1999, but only one FAP patient has subsequently undergone this procedure. Of these total of 43 FAP patients, 36 are currently alive: the one-year survival rate of patients after transplantation was 93%, and the five-year survival rate of these cases was 77%. Preoperative clinical severity and the nutritional status of patients are correlated with their outcome after liver transplantation. Domino (sequential) liver transplantation has been carried out in 20 domino recipients with end-stage liver diseases. Of the 20 domino recipients, 12 are currently alive. CONCLUSION: For FAP patients, these outcomes after the operation were very similar to those of OLT from cadaveric donors reported in other countries. Therefore, we concluded that for the treatment of FAP, LDLT from a living donor is equally effective as OLT from a cadaveric donor.

Adult↗