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Biomedical subjects

Seiji Yamaguchi

Publications and source records attributed to Seiji Yamaguchi.

At least 19 recordsLinked to original sources

The ubiquitin-like protein MNSFbeta regulates ERK-MAPK cascade.

MNSFbeta is a ubiquitously expressed member of the ubiquitin-like family that has been implicated in various biological functions. Previous studies have demonstrated that MNSFbeta covalently binds to intracellular proapoptotic protein Bcl-G in mitogen-activated murine T cells. In this study, we further investigated the intracellular mechanism of action of MNSFbeta in macrophage cell line, Raw 264.7 cells. We present evidence that MNSFbeta.Bcl-G complex associates with ERKs in non-stimulated Raw 264.7. We found that MNSFbeta.Bcl-G directly bound to ERKs and inhibited ERK activation by MEK1. In Raw 264.7 cells treated with MNSFbeta small interfering RNA (siRNA) lipopolysaccharide (LPS)-induced ERK1/2 activation was enhanced and LPS-induced JNK and p38 activation was unaffected. SiRNA-mediated knockdown of MNSFbeta increased tumor necrosis factor alpha (TNFalpha) expression at mRNA and protein levels in LPS-stimulated Raw 264.7 cells. Finally, we found that transfection with MNSFbeta expression construct resulted in a significant inhibition of LPS-induced ERK activation and TNFalpha production. Co-transfection experiments with MNSFbeta and Bcl-G greatly enhanced this inhibition. Collectively, these findings indicate that MNSFbeta might be implicated in the macrophage response to LPS.

Animals↗

Enhancement of drug delivery to bone: characterization of human tissue-nonspecific alkaline phosphatase tagged with an acidic oligopeptide.

Hypophosphatasia is caused by deficiency of activity of the tissue-nonspecific alkaline phosphatase (TNSALP), resulting in a defect of bone mineralization. Enzyme replacement therapy (ERT) with partially purified plasma enzyme was attempted but with little clinical improvement. Attaining clinical effectiveness with ERT for hypophosphatasia may require delivering functional TNSALP enzyme to bone. We tagged the C-terminal-anchorless TNSALP enzyme with an acidic oligopeptide (a six or eight residue stretch of L-Asp), and compared the biochemical properties of the purified tagged and untagged enzymes derived from Chinese hamster ovary cell lines. The specific activities of the purified enzymes tagged with the acidic oligopeptide were the same as the untagged enzyme. In vitro affinity experiments showed the tagged enzymes had 30-fold higher affinity for hydroxyapatite than the untagged enzyme. Lectin affinity chromatography for carbohydrate structure showed little difference among the three enzymes. Biodistribution pattern from single infusion of the fluorescence-labeled enzymes into mice showed delayed clearance from the plasma up to 18 h post infusion and the amount of tagged enzyme retained in bone was 4-fold greater than that of the untagged enzyme. In vitro mineralization assays with the bone marrow from a hypophosphatasia patient using each of the three enzymes in the presence of high concentrations of pyrophosphate provided evidence of bone mineralization. These results show the anchorless enzymes tagged with an acidic oligopeptide are delivered efficiently to bone and function bioactively in bone mineralization, at least in vitro. They suggest potential advantages for use of these tagged enzymes in ERT for hypophosphatasia, which should be explored.

Alkaline Phosphatase↗

Differences in methylation patterns in the methylation boundary region of IDS gene in Hunter syndrome patients: implications for CpG hot spot mutations.

Hunter syndrome, an X-linked disorder, results from deficiency of iduronate-2-sulfatase (IDS). Around 40% of independent point mutations at IDS were found at CpG sites as transitional events. The 15 CpG sites in the coding sequences of exons 1 and 2, which are normally hypomethylated, account for very few of transitional mutations. By contrast, the CpG sites in the coding sequences of exon 3, though also normally hypomethylated, account for much higher fraction of transitional mutations. To better understand relationship between methylation status and CpG transitional mutations in this region, the methylation patterns of 11 Hunter patients with transitional mutations at CpG sites were investigated using bisulfite genomic sequencing. The patient cohort mutation spectrum is composed of one mutation in exon 1 (one patient) and three different mutations in exon 3 (10 patients). We confirmed that in normal males, cytosines at the CpG sites from the promoter region to a portion of intron 3 were hypomethylated. However, specific CpG sites in this area were more highly methylated in patients. The patients with p.R8X (exon 1), p.P86L (exon 3), and p.R88H (exon 3) mutations had a hypermethylated condition in exon 2 to intron 3 but retained hypomethylation in exon 1. The same trend was found in four patients with p.A85T (exon 3), although the degree of hypermethylation was less. These findings suggest methylation patterns in the beginning of IDS genomic region are polymorphic in humans and that hypermethylation in this region in some individuals predisposes them to CpG mutations resulting in Hunter syndrome.

Adolescent↗

Distal myopathy with rimmed vacuoles in a case of opercular syndrome.

We report the case of a 30-year-old man with opercular syndrome who developed distal myopathy with rimmed vacuoles (DMRV). Muscle biopsy showed variation in fiber size and scattered fibers with rimmed vacuoles. The identification of a homozygous c. 1714G>C (p. V572L) mutation in the GNE gene genetically confirmed the diagnosis of DMRV, which is thought to be identical to hereditary inclusion body myopathy (HIBM). Our results indicate the possibility that other organs such as the central nervous system could be affected in DMRV/HIBM, although bilateral opercular lesions might have been caused by destructive events either in utero or in the perinatal period.

Adult↗

Two Japanese families with hyperekplexia who have a Arg271Gln mutation in the glycine receptor alpha 1 subunit gene.

We report two Japanese patients from two families with hyperekplexia who have a Arg271Gln mutation in the glycine receptor alpha 1 subunit gene. The clinical course of both patients was typical for hyperekplexia, characterized by neonatal hypertonia and exaggerated startle response, and which improved gradually with age. One was associated with umbilical hernia and hip dislocation, diagnosed at 11 months, while the other was diagnosed at 1 month. Both showed positive head retraction reflex. Four Japanese families have been reported as having hyperekplexia including our cases, of which three have shown the same missense Arg271Gln mutation, most frequently found in patients from Northern Europe and the United States.

Child, Preschool↗

Clinical, biochemical, and molecular findings in three patients with 3-hydroxyisobutyric aciduria.

3-Hydroxyisobutyric aciduria is a rare entity and affected individuals display a range of clinical manifestations including dysmorphic features and neurodevelopmental problems in the majority of patients. Here, we present two novel patients with 3-hydroxyisobutyric aciduria. To our knowledge, these are the 11th and 12th cases of 3-hydroxyisobutyic aciduria reported. It is believed that a deficiency in 3-hydroxyisobutyrate dehydrogenase is the most likely cause of this disorder. Measurement of 3-hydroxyisobutyrate dehydrogenase activity in fibroblasts homogenates of the two newly identified patients and a previously reported patient, however, revealed similar activities as in control fibroblasts. Since other enzymes with overlapping substrate specificity could conceal abnormal 3-hydroxyisobutyrate dehydrogenase activity, we cloned a candidate human cDNA for 3-hydroxyisobutyrate dehydrogenase (HIBADH). By heterologous expression in Escherichia coli, we showed that the product of the HIBADH gene indeed displays 3-hydroxyisobutyrate dehydrogenase activity. Mutation analysis of the corresponding gene in the patients suffering from 3-hydroxyisobutyric aciduria revealed no mutations. We conclude that HIBADH is not the causative gene in 3-hydroxyisobutyric aciduria.

Alcohol Oxidoreductases↗

Quantitative evaluation of sphingolipids using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry with sphingosylphosphorylcholine as an internal standard. Practical application to cardiac valves from a patient with Fabry disease.

Fabry disease is a glycolipid storage disorder caused by a defect of alpha-galactosidase A, and characterized by the systemic deposition of glycosphingolipids with terminal alpha-galactosyl moieties, mainly globotriaosylceramide, in tissues. Using delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF-MS), we analyzed the sphingolipids in the cardiac valves from a 49-year-old male patient with Fabry disease who suffered from congestive cardiac failure. Crude lipids were extracted from the cardiac valves with chloroform and methanol. After mild alkaline treatment of the crude lipids, a sphingolipid fraction was prepared and analyzed by DE MALDI-TOF-MS. The results were as follows: (a) ion peaks with m/z values corresponding to different ceramide trihexoside (CTH) species were detected; (b) with sphingosylphosphorylcholine (SPC) as the internal standard for semi-quantification of CTH, the relative peak height of CTH was calculated and plotted versus its amount loaded on the sample plate for MALDI-TOF-MS. The relative peak height of CTH with fatty acid C16:0 showed linearity between 0 and 50 ng CTH (regression coefficient, r>0.95); (c) semi-quantitative analysis revealed striking accumulation of CTH in the cardiac valves from the patient with Fabry disease. It was indicated that the accumulation of CTH in cardiac valves from Fabry disease patients can be detected with the DE MALDI-TOF-MS method. SPC is commercially available, and this semi-quantitative method involving MALDI-TOF-MS was found to be convenient, reliable and useful for CTH. It is expected to be applied to the quantification of CTH in small amounts of body fluids or other tissues and to clinical examination. It is also expected to be applicable to the quantification of other glycosphingolipids.

Chromatography, Thin Layer↗

[Cost-effectiveness analysis of routine immunization for varicella in Japan].

OBJECTIVE: Immunization for varicella is not currently included in routine immunizations in Japan. This study was conducted to assess test its cost-effectiveness when it becomes a routine. METHODS: We surveyed and collected information for the year beginning 15th June 2004 in one area. Almost all 11 pediatric clinics or hospitals in the area cooperated in this survey. There was a questionnaire form for families and for doctors. Absent days from routine tasks, i.e., job, housekeeping or study, for family nursing and others were asked on family form. Medical costs and other costs were asked on doctor form. Neither form included the patient's name or name of the medical institution. Doctors explained this survey to patients' family on their first visiting day and asked to cooperate. If they refused the doctor form was also discarded. Since family form was written after recovery and mailed, cooperation in this survey was voluntary. Opportunity cost for family nursing is estimated as opportunity cost based on the 2002 Basic Surveillance of Wage Structure. The burden of sequel cases was estimated assuming six million yen per Quality-adjusted Life Years (QALY). Total number of patients was estimated to be 0.84 million, which includes unvaccinated people in a birth cohort. We adopted incremental benefit cost ratios form societal viewpoint as a measure. RESULTS: We collected 402 data from the doctor form and 265 from the family form. Total disease burden in all of Japan is estimated to be 52.2 billion yen, but opportunity cost accounted for 80%. The incremental benefit cost rations averaged more than 4 when vaccination cost is assumed to be five to twelve thousand yen. The lower limit of the confidence intervals is about 1.5. DISCUSSION AND CONCLUSION: The disease burden of varicella was greater than measles in 2000, when there were measles 0.2 million patients. The incremental benefit cost ratio showed that there will almost surely be an additional benefit due to routine immunization is greater than the additional cost. Therefore, we found strong evidence for routine immunization for varicella.

Chickenpox↗

Clinical and biochemical studies on Chinese patients with methylmalonic aciduria.

Methylmalonic aciduria is a common organic aciduria disease. Recently, gas chromatography-mass spectrometry has been used to diagnose methylmalonic aciduria in China. Often, however, the diagnosis of methylmalonic aciduria is delayed because of a lack of technical expertise and the limited experience of general clinicians in China. In this study, the natural history, clinical features, and outcome of 77 Chinese patients with methylmalonic aciduria were investigated. Of the 77 patients, 31 (40.3%) had isolated methylmalonic aciduria and 46 (59.7%) had methylmalonic aciduria combined with homocystinemia. Thus, we observed a higher rate of the combined disease than studies conducted in other countries, suggesting that it might be more common in China. Total plasma homocysteine measurement might enable differential diagnoses of methylmalonic aciduria to be distinguished. The clinical spectrum of these 77 patients with methylmalonic aciduria ranged from neonatal death and severe symptoms to benign asymptomatic organic aciduria. Neonatal and infantile onset, which was a characteristic of the majority of cases, was associated with a greater severity relative to later-onset cases. Among the 17 cases who had onset after 3 years of age, only 1 patient had isolated methylmalonic aciduria and 16 had combined methylmalonic aciduria and homocystinemia. Nine of the patients with combined methylmalonic aciduria and homocystinemia completely recovered and exhibited normal intelligence, whereas seven improved, with a mild handicap.

Adolescent↗

[Case report of skin tuberculosis after living renal transplantation].

We report on a mycobacterium tuberculosis after renal transplantation. This is, to our knowledge, the first case report on an isolated skin tuberculosis with mycobacterium tuberculosis after renal transplantation. A-68-year-old renal transplant recipient presented with a nodule in his right breast. A diagnosis of a mycobacterium tuberculosis skin infection was made and antimycobacterial therapy was started.

Aged↗

[Mass screening for prostate cancer in Ikeda City Osaka].

PURPOSE: Screening with prostate specific antigen (PSA) to detect prostate cancer was started in Ikeda City Osaka from 2003 as part of the city's health program. We evaluated the first year's result. MATERIAL AND METHOD: Fifty-year-old or elder men living in Ikeda City who wanted to have their serum PSA level (Tandem-R) measured to screen for prostate cancer was entered into the screening program. Men whose PSA levels detected to exceed 4.1 ng/ml were told they should visit a urologist for further examinations to detect possible prostate cancer. These examinations included prostate biopsy. The results of further examinations were reported to Ikeda City and evaluated. RESULTS: The population of fifty-years-old or elder men in Ikeda City was 18,161. 3738 (21.0%) men had their serum PSA levels measured. 367 (9.81%) of the men were told they should undergo further examinations to detect possible prostate cancer. 263 (71.7%) men visited a urologist for further examinations, and prostate biopsy was performed in 138 (52.5%) of them. Among these 138, prostate cancer diagnosed in 91 (65.9%). The positive rate of prostate biopsy was 65.9% (91/138), The detection rate for prostate cancer was therefore 2.43% (91/3738). Patient's numbers for each clinical stage were 57 (62.6%) in B, 30 (32.9%) in C, 4 (4.4%) in D. CONCLUSION: Prostate cancer was diagnosed in 2.34% of 3738 men who had their serum PSA levels measured, and in stage B two thirds had a positive diagnosis. PSA screening to detect prostate cancer as one of the health checks in Ikeda City was useful in detecting early prostate cancer.

Aged↗

[Testicular cancer metastatic to multiple organs including the stomach, kidneys, and skin: a case report].

A 39-year-old man whose chief complaints were general fatigue and bloody phlegm was diagnosed with testicular cancer and underwent left high orchiectomy at an affiliated hospital. The histopathologic diagnosis was chorio carcinoma. Several imaging examinations revealed the metastases in the lung, liver, brain, stomach, kidneys and skin. In spite of various chemotherapies, he died 17 months after the operation. Skin metastasis of testicular cancer is very rare and this is the twelfth case reported in the world, to our knowledge. The significance of skin metastasis in testicular cancer is discussed.

Adult↗

Development of MPS IVA mouse (Galnstm(hC79S.mC76S)slu) tolerant to human N-acetylgalactosamine-6-sulfate sulfatase.

Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive disease caused by N-acetylgalactosamine-6-sulfate sulfatase (GALNS) deficiency. In recent studies of enzyme replacement therapy for animal models with lysosomal storage diseases, cellular and humoral immune responses to the injected enzymes have been recognized as major impediments to effective treatment. To study the long-term effectiveness and side effects of therapies in the absence of immune responses, we have developed an MPS IVA mouse model, which has many similarities to human MPS IVA and is tolerant to human GALNS protein. We used a construct containing both a transgene (cDNA) expressing inactive human GALNS in intron 1 and an active site mutation (C76S) in adjacent exon 2 and thereby introduced both the inactive cDNA and the C76S mutation into the murine Galns by targeted mutagenesis. Affected homozygous mice have no detectable GALNS enzyme activity and accumulate glycosaminoglycans in multiple tissues including visceral organs, brain, cornea, bone, ligament and bone marrow. At 3 months, lysosomal storage is marked within hepatocytes, reticuloendothelial Kupffer cells, and cells of the sinusoidal lining of the spleen, neurons and meningeal cells. The bone storage is also obvious, with lysosomal distention in osteoblasts and osteocytes lining the cortical bone, in chondrocytes and in the sinus lining cells in bone marrow. Ubiquitous expression of the inactive human GALNS was also confirmed by western blot using the anti-GALNS monoclonal antibodies newly produced, which resulted in tolerance to immune challenge with human enzyme. The newly generated MPS IVA mouse model should provide a good model to evaluate long-term administration of enzyme replacement.

Animals↗

Enzymatic diagnosis of medium-chain acyl-CoA dehydrogenase deficiency by detecting 2-octenoyl-CoA production using high-performance liquid chromatography: a practical confirmatory test for tandem mass spectrometry newborn screening in Japan.

Many of the previously described enzymatic assay methods for the diagnosis of medium-chain acyl-CoA dehydrogenase (MCAD) deficiency have been dependent upon the measurement of radioisotope-labeled co-products or reduction of electron acceptors. We have developed a direct assay method to detect 2-enoyl-CoA production using high-performance liquid chromatography (HPLC). Crude cell lysate prepared from lymphocytes were incubated with n-octanoyl-CoA and ferrocenium hexafluorophosphate. The detection of 2-octenoyl-CoA was significantly reproducible. We applied the assay to samples from four infants suspected to have MCAD deficiency by tandem mass spectrometry (MS/MS) newborn screening conducted in the Hiroshima area of Japan. Three of them were proved to have pathologically reduced residual enzyme activities, although they were associated with various clinical and biochemical phenotypes. In addition, another symptomatic Japanese patient and her presymptomatic sibling who were detected by MS/MS selective screening were successfully diagnosed by our enzymatic assay. These results indicate that the method can be a useful confirmatory test for MS/MS screening of MCAD deficiency.

Acyl Coenzyme A↗

Prenatal diagnosis for organic acid disorders using two mass spectrometric methods, gas chromatography mass spectrometry and tandem mass spectrometry.

We performed prenatal diagnosis of organic acid disorders using two mass spectrometric methods; gas chromatography mass spectrometry (GC/MS) and tandem mass spectrometry (ESI/MS/MS). Of 28 cases whose amniotic fluid was tested, 11 cases were diagnosed as "affected". All cases whose samples were diagnosed as "unaffected" were confirmed to have no symptoms or abnormalities in urinary organic acid analysis after birth. Of the 11 "affected" cases, two cases were missed by ESI/MS/MS but not by GC/MS. When the stability of metabolites in amniotic fluid was checked, it was found that acylcarnitines degraded in one week at room temperature, whereas organic acids such as methylmalonate or methylcitrate were stable for at least 14 days. Prenatal diagnosis by analysis using simultaneous two or more methods may be more reliable, though attention should be paid to sample transportation conditions.

Amniotic Fluid↗

Mutation and polymorphism spectrum of the GALNS gene in mucopolysaccharidosis IVA (Morquio A).

Mucopolysaccharidosis IVA (MPS IVA; Morquio A disease) is an autosomal-recessive disorder caused by a deficiency of lysosomal N-acetylgalactosamine-6-sulfate sulfatase (GALNS; E.C.3.1.6.4). GALNS is required to degrade glycosaminoglycans, keratan sulfate (KS), and chondroitin-6-sulfate. Accumulation of undegraded substrates in lysosomes of the affected tissues leads to a systemic bone dysplasia. We summarize information on 148 unique mutations determined to date in the GALNS gene, including 26 novel mutations (19 missense, four small deletions, one splice-site, and two insertions). This heterogeneity in GALNS gene mutations accounts for an extensive clinical variability within MPS IVA. Seven polymorphisms that cause an amino acid change, and nine silent variants in the coding region are also described. Of the analyzed mutant alleles, missense mutations accounted for 78.4%; small deletions, 9.2%; nonsense mutation, 5.0%; large deletion, 2.4%; and insertions, 1.6%. Transitional mutations at CpG dinucleotides accounted for 26.4% of all the described mutations. The importance of the relationship between methylation status and distribution of transitional mutations at CpG sites at the GALNS gene locus was elucidated. The three most frequent mutations (over 5% of all mutations) were represented by missense mutations (p.R386C, p.G301C, and p.I113F). A genotype/phenotype correlation was defined in some mutations. Missense mutations associated with a certain phenotype were studied for their effects on enzyme activity and stability, the levels of blood and urine KS, the location of mutations with regard to the tertiary structure, and the loci of the altered amino acid residues among sulfatase proteins.

Animals↗

Brain stem glioblastoma with multiple large cyst formation and leptomeningeal dissemination in a 4-year-old girl.

The authors report a 4-year-old girl who developed brain stem glioblastoma. Meningeal irritation was present at onset. Magnetic resonance imaging revealed intracranial and intraspinal leptomeningeal dissemination, which progressed faster than the original tumor. Multiple large cysts developed at the interhemispheric and prepontine cisterns, resulting in progressive obstructive hydrocephalus. The patient survived only 5 months after presentation. Histology was verified by autopsy.

Arachnoid↗