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M Ota

Publications and source records attributed to M Ota.

At least 19 recordsLinked to original sources

Japanese population data for eight X-STR loci using two new quadruplex systems.

Using two new X-chromosome short tandem repeats (X-STR) multiplex (quadruplex) systems, we investigated Japanese population data (drawn from 401 individuals) for eight X-STR loci (DXS10011, DXS9898, DXS8377, HPRTB, DXS7132, DXS6797, GATA172D05, and DXS6807). Allele typing with the systems was successful for all loci. The combined powers of discrimination of the eight loci in men and women were 0.999997 and 0.9999999996, respectively. We conclude that combined analyses of the eight X-STR loci using these two quadruplex polymerase chain reaction systems represent a powerful tool for Japanese forensic practice.

Female↗

MiniX-STR multiplex system population study in Japan and application to degraded DNA analysis.

We sought to evaluate a more effective system for analyzing X-chromosomal short tandem repeats (X-STRs) in highly degraded DNA. To generate smaller amplicon lengths, we designed new polymerase chain reaction (PCR) primers for DXS7423, DXS6789, DXS101, GATA31E08, DXS8378, DXS7133, DXS7424, and GATA165B12 at X-linked short tandem repeat (STR) loci, devising two miniX-multiplex PCR systems. Among 333 Japanese individuals, these X-linked loci were detected in amplification products ranging in length from 76 to 169 bp, and statistical analyses of the eight loci indicated a high usefulness for the Japanese forensic practice. Results of tests on highly degraded DNA indicated the miniX-STR multiplex strategies to be an effective system for analyzing degraded DNA. We conclude that analysis by the current miniX-STR multiplex systems offers high effectiveness for personal identification from degraded DNA samples.

Asian People↗

Serological diversity demonstrable by a set of monoclonal antibodies to eight serotypes of the mutans streptococci.

A set of monoclonal antibodies were prepared by the conventional cell fusion of myeloma cells (SP2/0-Ag14) with spleen cells from BALB/c mice immunised with whole cells of a strain of mutans streptococci. Their specificities were examined against 35 reference strains of mutans streptococci, 34 reference strains of other oral streptococci and 8 reference strains of other microorganisms often inhabiting the oral cavity. Specificity was examined by enzyme immunoassay using whole cells. A total of 52 strains, consisting of 19 strains isolated in Japan, 19 strains isolated in Italy and 14 strains isolated in England, were characterised by conventional physiological and biochemical tests and then serotyped by the use of 8 monoclonal antibodies with different specificities. They were also confirmed by guanine-plus-cytosine contents of their nucleic acid and DNA-DNA hybridisation test. The results indicated that all monoclonal antibodies are useful for identification of 8 serotypes of the mutans streptococci responsible for dental caries. They also suggest the existence of more serological varieties among mutans species.

Antibodies, Bacterial↗

Allele frequencies of the six miniSTR loci in a population from Japan.

Allele frequencies and forensic parameters for the six miniSTR loci D1S1677, D2S441, D4S2364, D10S1248, D14S1434, and D22S1045 were investigated in a sample of 142 unrelated healthy Japanese individuals. The polymerase chain reaction (PCR) products contained within the six loci were less than 119 bp in size. The frequency distributions in the six short tandem repeat (STR) loci showed no deviations from Hardy-Weinberg equilibrium expectations. The accumulated powers of discrimination and power of exclusion for the six loci were 0.999998 and 0.98, respectively. It was thus considered that due to the small PCR products and the moderate degree of polymorphism, analysis with use of the six miniSTR loci was highly beneficial for the forensic analysis of degraded DNA.

Asian People↗

The haplotype block, NFKBIL1-ATP6V1G2-BAT1-MICB-MICA, within the class III-class I boundary region of the human major histocompatibility complex may control susceptibility to hepatitis C virus-associated dilated cardiomyopathy.

Cardiomyopathy is a heart muscle disease with impaired stretch response that can result in severe heart failure and sudden death. A small proportion of hepatitis C virus (HCV)-infected patients may be predisposed to develop dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). The molecular mechanisms involved in the predisposition remain unknown due in part to the lack of information on their genetic background. Because the human leukocyte antigen (HLA) region has a pivotal role in controlling the susceptibility to HCV-induced liver disease, we hypothesized that particular HLA alleles and/or non-HLA gene alleles within the human major histocompatibility complex (MHC) genomic region might control the predisposition to HCV-associated DCM (HCV-DCM) and/or HCV-associated HCM (HCV-HCM). Here, we present mapping results of the MHC-related susceptibility gene locus for HCV-associated cardiomyopathy by analyzing microsatellite and single nucleotide polymorphism markers. To delineate the susceptibility locus, we genotyped 44 polymorphic markers scattered across the entire MHC region in a total of 59 patients (21 HCV-DCM and 38 HCV-HCM) and 120 controls. We mapped HCV-DCM susceptibility to a non-HLA gene locus spanning from NFKBIL1 to MICA gene loci within the MHC class III-class I boundary region. Our results showed that HCV-DCM was more strongly associated with alleles of the non-HLA genes rather than the HLA genes themselves. In addition, no significant association was found between the MHC markers and HCV-HCM. This marked difference in the MHC-related disease susceptibility for HCV- associated cardiomyopathy strongly suggests that the development of HCV- DCM and HCV-HCM is under the control of different pathogenic mechanisms.

Adaptor Proteins, Signal Transducing↗

Clinical course of fetal congenital atrioventricular block in the Japanese population: a multicentre experience.

OBJECTIVES: To elucidate the prenatal and postnatal course of fetal congenital atrioventricular block (CAVB) during the past decade in the Japanese population. DESIGN: Retrospective multicentre study. All fetuses with CAVB in 10 Japanese institutions in the period from January 1990 to August 2001 were included. PATIENTS: Of the 48 fetuses with CAVB, 17 had a congenital heart defect (CHD) (14 with left atrial isomerism) and 31 had a structurally normal heart (22 with positive maternal autoantibodies). Gestational age at diagnosis was 15 to 38 (median 26) weeks. RESULTS: Of the 17 fetuses with a CHD, three were aborted, one died before birth, and eight died after birth (three in the neonatal period and five after the neonatal period). Of the 31 fetuses without a CHD, two died before birth and two died after birth. CHD (p = 0.005) and the presence of fetal hydrops (p = 0.05) were significant risk factors for death. However, fetal ventricular and atrial heart rates, gestational age at delivery, and birth weight were not related to death. Transplacental medication of sympathomimetics increased the fetal heart rate in five of eight fetuses treated. Dexamethasone did not improve the degree of heart block in any of the six fetuses treated. Postnatally, pacemakers were implanted in 30 of 40 babies. Four fetuses with maternal autoantibodies had decreased cardiac function. CONCLUSIONS: CHD and fetal hydrops are risk factors for prenatal and postnatal death. The fetal ventricular rate of 55 beats/min did not appear to be a threshold value by which to predict fetal hydrops. Patients with CAVB should be subjected to close long term follow up to check for the need for pacemaker implantation or for late onset cardiac dysfunction.

Anti-Arrhythmia Agents↗

Effect of stress ratio on the fatigue behaviour of compact bone.

During the fatigue process of bone, cracks generally initiate from the inherent defects existing in the bone. The fatigue lives of bone specimens at different stress levels as well as at different stress ratios R were evaluated using a computer simulation in which the crack propagation behaviour initiated from the inherent defects in the bone are herein considered. The S-N curves as well as the distributions of fatigue lives obtained by the simulations accurately conform with the experimental results. With the strain threshold epsilon(max) representing fatigue failure of the bone specimen, the values of 1500 microepsilon for R = -1, 2500 microepsilon for R = 0.1 and 4000 microepsilon for R = 10 were extrapolated from the simulations. These values conform with experimental values reported in the literature. Such conformity indicates that the strain threshold for fatigue failure is associated with the threshold value for crack propagation.

Animals↗

Interactions between clarithromycin and digoxin in patients with end-stage renal disease.

OBJECTIVE: To report a significant increase in the serum levels of digoxin associated with the use of clarithromycin in six patients undergoing renal replacement therapy. CASE SUMMARY: All six patients were males with end-stage renal disease and in need of renal replacement therapy. Four patients were anuric. The mean age was 78.8 +/- 5.8 (66-83) years. All patients except one, who was treated by hemofiltration, were treated by hemodialysis. All patients except one, who had been treated with metildigoxin (0.35 mg/week), were also taking digoxin (0.375 mg/week). Clarithromycin was administered at a dose of 200-400 mg/day for the treatment of bronchitis in all patients. The concomitant administration of clarithromycin increased serum digoxin levels from 1.8-4.0-fold in all cases. In two of six cases, a high probability of digoxin intoxication and suspicion of digoxin intoxication was evident. In three of six cases, serum digoxin levels increased within 12 days after the co-administration of clarithromycin, while in the other three cases, serum digoxin levels were increased 53-190 days after the administration of clarithromycin. CONCLUSION: The simultaneous administration of clarithromycin caused an increase in digoxin levels in six patients undergoing renal replacement therapy. The increase in the serum digoxin can be attributed to the inhibition of P-glycoprotein in the intestine and/or bile capillary rather than the kidney by clarithromycin since renal function was dramatically impaired, and four of the patients were anuric. The issue of why serum digoxin levels were increased so late in three patients undergoing renal replacement is unclear. However, this interaction seemed to be clinically significant even in ESRD patients, whose renal function was highly impaired. The simultaneous use of digoxin and clarithromycin should be avoided even in patients undergoing renal replacement therapy whose renal function is impaired, since digoxin levels may increase unexpectedly.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Pancreas-kidney transplantation in Japan: impact of cyclosporine on the development of immunosuppressive therapy.

The number of pancreas transplants reached 16,043 worldwide in October 2001, with 1800 performed in 2000. Since the introduction of cyclosporine (CyA) in 1979, a regimen consisting of CyA, azathioprine, and steroids has been shown to improve long-term survival of clinical transplants. In Japan, the first simultaneous pancreas-kidney transplantation was performed in 1984, using organs from a brain-dead donor. This procedure was followed by 14 pancreas transplantations from cardiac arrest donors. All cases utilized a CyA-based regimen with antilymphocyte globulin or OKT3 induction. Six of the 15 recipients required less insulin postoperatively. Under a new transplant law enforced in 1997, 10 pancreas/pancreas-kidney transplantations were performed in patients diagnosed with end-stage renal failure due to diabetes mellitus type 1. In 1 patient, the graft failed due to venous thrombosis, but the other 9 recipients achieved an increased quality of life without the need for insulin or for dialysis. Pancreas transplantation represents an effective treatment worldwide and in Japan, due to the availability of CyA or tacrolimus in combination with other agents such as antilymphocyte globulin, OKT3, or mycophenolate mofetil. This investigation presents the results of pancreas-kidney transplantation in Japan, in comparison with those worldwide, and describes a recent case in Japan.

Adult↗

Association of polymorphic MHC microsatellites with GVHD, survival, and leukemia relapse in unrelated hematopoietic stem cell transplant donor/recipient pairs matched at five HLA loci.

In order to determine whether matching/mismatching for microsatellite polymorphism provides useful information on acute graft-vs-host disease (GVHD), survival, and leukemia relapse in hematopoietic stem cell (HSC) transplantation, we genotyped for polymorphisms at 13 microsatellite loci within the major histocompatibility complex (MHC) of 100 unrelated HSC transplant donor-recipient pairs who were matched at five classical human leukocyte antigen (HLA) loci. A high percentage of allele matching was obtained for five microsatellite loci, DQCARII (96%), MICA (93%), MIB (89%), C1-3-1 (93%), and D6S510 (97%), that are localized within 100 kb of the HLA-DR, HLA-DQ, HLA-B, HLA-C, or HLA-A locus. In contrast, the other eight microsatellites are located farther away from the HLA classical loci and have much lower percentages of allele matching [e.g. tumor necrosis factor a (TNFa) (73%), TNFd (74%), D6S273 (64%), C3-2-11 (46%), C5-3-1 (50%), C5-4-5 (63%), C5-2-7 (68%), and D6S265 (81%)]. Therefore, there were at least eight microsatellite markers with relatively high percentages of mismatches in the donor/recipient pairs with acute or chronic GVHD, poor graft survival, and leukemia relapse. However, there were no statistically significant associations between mismatched donor-recipient pairs at the 13 microsatellite loci and acute or chronic GVHD, graft survival, and leukemia relapse. Nevertheless, allele matching at the microsatellite TNFd locus near the TNFa gene was found by the Fisher's exact double-sided test to be significantly associated with decreased survival in the grade III/IV acute GVHD group. Overall, these results suggest that the matching of microsatellite polymorphisms within the HLA region, especially the ones farthest from the classical HLA loci, was not useful indicator for the outcome of HSC transplantation from unrelated donors. In this regard, the future determination of the genome-wide microsatellite genotypes in HLA-matched donor-recipient pairs, outside the MHC, may be a better possibility for identifying minor histocompatibility genes in linkage disequilibria with microsatellites as potential predictive markers for the occurrence of acute GVHD and survival rate in HSC transplantation.

Adolescent↗

Expression of p21(Waf1/Cip1) predicts response and survival of esophageal cancer patients treated by chemoradiotherapy.

Chemoradiotherapy is a multimodal therapy routinely used as a primary treatment for advanced esophageal cancer. However, it is beneficial only to patients who respond. To identify pretreatment markers predicting response and survival, we examined the expression of cell cycle regulatory molecules, p53, p21(Waf1/Cip1) cyclin D1, and CDC25B, in biopsy specimens from 76 patients with stage III and stage IV squamous cell carcinoma. Overexpression of p53, p21, cyclin D1 and CDC25B was observed in 58%, 30%, 28%, and 32% of patients, respectively. The expression of p21 correlated significantly with response to chemoradiotherapy (P = 0.0001). Survival of patients with p21-expressing tumors was better than that of patients with p21-negative tumors (P = 0.013). Expression of other genes was not significantly correlated with treatment response and survival. In patients with p53-negative tumors, survival of those patients with p21-positive tumors was significantly higher than that of those with p21-negative tumors (P = 0.0452), but no significant difference was found in patients with p53-positive tumors. Multivariate analysis revealed that p21 expression was an independent variable among pretreatment parameters in predicting survival. These results suggest that p21 expression is potentially useful for predicting the response to chemoradiotherapy and survival of patients with advanced esophageal squamous cell cancer.

Biopsy↗

Involvement of dendritic cells in sarcoidosis.

BACKGROUND: Sarcoidosis is a systemic granulomatous disease of unknown aetiology. It has been suggested that T helper type 1 (Th1) polarisation is associated with the pathophysiology of sarcoidosis, but the mechanism of skewing towards Th1 has not been elucidated. Dendritic cells (DCs) are known to regulate immune responses. This study was performed to determine whether DCs are involved in the aetiology of sarcoidosis. METHODS: The numbers of peripheral blood DCs in 24 patients with sarcoidosis were analysed and biopsy specimens from four patients were stained immunohistochemically using monoclonal antibodies. RESULTS: The numbers of both myeloid and lymphoid DC subsets were significantly decreased in the blood and mature DCs were found in the granulomas of patients with sarcoidosis. A number of interferon-gamma (IFN-gamma) producing T cells were also detected in the sarcoid granuloma, as well as many interleukin (IL)-4 producing T cells. Double staining of the biopsy specimen using anti-fascin and anti-CD3 antibodies showed an anatomical interaction between DCs and T cells. CONCLUSIONS: These findings suggest that the blood DC subsets may migrate into the affected tissues, contributing to the formation of the granulomas in sarcoidosis. It is hypothesised that the migrating DCs may regulate the T cell response in sarcoidosis, at least in the granulomatous lesions.

Adult↗

Multimodality treatments with endoscopic mucosal resection of esophageal squamous cell carcinoma with submucosal invasion.

BACKGROUND AND STUDY AIMS: A standard treatment for esophageal squamous cell carcinoma (SCC) with submucosal invasion is considered to be radical resection at present. In this study, we evaluated the efficacy of multimodality treatments with endoscopic mucosal resection (EMR) of esophageal SCC with submucosal invasion. METHOD: Eighteen cases of SCC with submucosal invasion were treated with EMR. Lymphatic invasion was found in 11 cases (67%), and there were no cases of blood vessel invasion. EMR was performed prior to any other treatment. Chemotherapy and/or radiotherapy were added if indicated by the histopathological features. RESULTS: There were no cases of local recurrence. Lymph-node recurrence was detected in 1 case treated with EMR alone. There were no cases of cancer death. The overall survival rate was 83% in all patients. CONCLUSIONS: Multimodality treatments with EMR were effective in treating esophageal SCC with submucosal invasion.

Adult↗

Long-term follow-up of hepatitis C virus infection: HLA class II loci influences the natural history of the disease.

Hepatitis C virus (HCV) causes various grades of chronic liver disease, ranging from an asymptomatic state to cirrhosis. To assess genetic factors of disease severity, we selected two HCV patient groups according to the following stringent criteria: (i) asymptomatic carrier state (ASC) defined by HCV infection for more than 20 years, normal alanine aminotransferase levels for the past 5 years as well as normal liver histology and/or shape and (ii) liver cirrhosis (LC) as diagnosed by clinical symptoms, liver biopsy and/or ultrasonography. A total of 103 chronically infected Japanese HCV patients (43 ASC and 60 LC) were analyzed. HLA class I and II alleles were established using low resolution DNA typing. HLA-DRB1 and DQB1 genotypes were inferred upon polymerase chain reaction-restriction fragment length polymorphism analysis. Two hundred and one anti-HCV-negative ethnically matched controls were included. The frequencies of DRB1*12 (*1201 and *1202), DQB1*0301 and DRB3*03 alleles were higher in patients with ASC than in those with LC (odds ratio (OR) 11.23, OR 4.25, and OR 3.22, respectively). The frequency of DQB1*0503 were lower in ASC patients compared to LC patients (OR 0.05). No significant differences between groups were observed for age, sex, source of infection, HCV genotype or viral loads. Our findings establish that certain HLA class II alleles strongly influence disease progression following HCV infection.

Aged↗

Association of MHC dimorphic Alu insertions with HLA class I and MIC genes in Japanese HLA-B48 haplotypes.

A large proportion of Japanese with the HLA-B48 allele have a MICA gene deletion associated with a MICB null allele within the class I region of the Major Histocompatibility Complex (MHC). Here, we report for the first time a novel positive association between the presence of a polymorphic Alu insertion, AluyMICB, within the first intron of the MICB gene and the MICAdel/MICBnull/HLA-B48 haplotype for five of six well-characterized Japanese cell-lines. The AluyMICB insertion was found to be present at a frequency of 0.242 in 86 Japanese tissue donors and in four of the five individuals with the HLA-B48 allele. The AluyMICB insertion was also associated with at least three different MICB alleles, *0102, *0107N and *0105, and three different HLA-B alleles, B13, B48 and B57, respectively, in the seven Workshop cell-lines (the 4th Asia-Oceania Histocompatibility Workshop, and the 10th International Histocompatibility Workshop) and the six Japanese cell-lines that were selected for this study. Based on the analysis of associations between different polymorphic markers within the beta block, the MICB*0102 allele was inferred to be the ancestral form of the MICB*0105 and MICB*0107N alleles. The AluyMICB polymorphism can now be used to further investigate its relationship with other MICB alleles and consequently their origins. In addition, we have examined the absence and presence of three other polymorphic Alu markers distributed within the alpha block of the class I region of the HLA-B48/AluyMICB haplotype. We conclude that the extended HLA-B haplotypes are best defined by considering multiple genomic sites including the four polymorphic Alu insertions described in this study.

Alu Elements↗

Epidemiological characteristics of acute pulmonary thromboembolism in Japan.

AIM: In Japan, acute pulmonary thromboembolism (APTE) is still rare, but the number of patients with APTE has been steadily increasing. It is important for early diagnosis and early management of APTE to recognize epidemiological characteristics of this condition. METHODS: We investigated the epidemiological characteristics of 252 patients with APTE who were admitted to our institutions between 1975 and 2001. APTE was more prevalent in women that in men. It was observed the most in the age group between 50s to 70s, especially in women. Many patients had prolonged immobilization, recent major operation, obesity, or cancer, as risk factors for venous thromboembolism. One hundred and thirty-eight patients developed APTE in hospital; 60 patients were in Department of Internal Medicine, 28 in General Surgery, 15 in Orthopedics, 15 in Obstetrics and Gynecology, and 20 in other services. RESULTS: Among 58 patients with malignancy, 43% had cancers in digestive organs, 21% in gynecological, and 17% in urological. Among 61 patients who were examined for the presence of thrombophilia, 13 patients had inherited thrombophilia (8 protein C deficiency, 4 protein S deficiency, and 1 antithrombin III deficiency) 11 had antiphospholipid antibodies which indicated thrombophilia. Five out of the above 61 patients (8%) had no obvious risk factors including thrombophilia. CONCLUSION: The findings in our patients were almost the same as those in Western patients, except for some points. These results might be useful to establish a preventive approach for APTE in Japan.

Acute Disease↗

Sequencing-based typing of HLA-B*51 alleles and the significant association of HLA-B*5101 and -B*5108 with Behçet's disease in Greek patients.

Behçet's disease (BD) is widely known to be strongly associated with human leukocyte antigen (HLA) B51 in many different ethnic groups.Recently, HLA-B51 allele typing of Greek BD patients was performed to study the distribution of B*5101-B*5107 alleles in this Greek population, the B51 antigen strongly associated with BD was found to be predominantly encoded by allele B*5101. As it is now known that the B51 antigen can be encoded by 21 alleles, B*5101-B*5121, we performed HLA-B*51 allele genotyping among 58 Greek patients with BD. After serological HLA typing, typing of HLA-B*51 alleles was performed using the polymerase chain reaction-sequencing-based typing (PCR-SBT) method. The frequency of the B51 antigen was found to be significantly higher in the patient group as compared with the control group (75.9% of patients vs 22.0% of controls. In the genotyping of B51 alleles, 34 out of 44 B51-positive patients possessed B*5101, 13 out of the 44 carried B*5108. In contrast, all of the 9 B51-positive normal controls carried B*5101. This study revealed a strong association between Greeks with BD, both B*5101, B*5108, provided important insights into the molecular mechanism underlying the association between HLA status, this disease.

Alleles↗