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Masao Ota

Publications and source records attributed to Masao Ota.

At least 37 records · Page 2Linked to original sources
PubMed2005

Rapid assignment of the swine major histocompatibility complex (SLA) class I and II genotypes in Clawn miniature swine using PCR-SSP and PCR-RFLP methods.

BACKGROUND: Inbred miniature swine with defined novel SLA haplotypes will be useful in allo- and xeno-transplantation studies, which can be carried out representing variable combinations of SLA haplotypes. METHODS: In Clawn miniature swine, two haplotypes (c1 and c2) and one crossover haplotype (c3) have been assigned by nucleotide sequence determination of RT-PCR products of the three SLA classical class I genes and two SLA class II genes. To select SLA class I and II homozygotes in Clawn miniature swine individuals, we developed a rapid and simple SLA-class I- and II-DNA typing method by a combination of polymerase chain reaction-sequence specific primer (PCR-SSP) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques. RESULTS: Seven allele specific primer pairs were designed for amplification of the second exons of three SLA class I genes, SLA-1, SLA-2, and SLA-3, and one SLA class II gene, DRB1. Furthermore, based on PCR-RFLP patterns in the SLA-DQB1 gene, two allelic variants were recognized in the second exon in the Clawn miniature swine. Three haplotypes, c1, c2 and c3, were simply identified by the combination of PCR-SSP and PCR-RFLP methods in 22 samples from five families. A single allele at each of the class I and II genes was also observed in seven samples as SLA class I and II homozygotes with either the c1 or c2 haplotype. CONCLUSIONS: The combination of PCR-SSP and PCR-RFLP methods facilitate the rapid identification of the three haplotypes and SLA class I and II homozygotes in individual Clawn miniature swine.

Alleles↗
PubMed2004

Polymorphisms of renin-angiotensin system genes with high-altitude pulmonary edema in Japanese subjects.

STUDY OBJECTIVES: The renin-angiotensin system (RAS), including angiotensin-converting enzyme (ACE) and angiotensin II type 1 receptor (AT(1)R), plays an important role in the pathogenesis of pulmonary hypertension, which is suggested to be critical in the development of high-altitude pulmonary edema (HAPE). Investigating the associations of the polymorphisms in the genes of RAS with HAPE is to elucidate the genetic background underlying this disease. DESIGN: A cross-sectional, case-control study. SETTING: Shinshu University Hospital, Matsumoto, Japan. PARTICIPANTS: Forty-nine HAPE-susceptible (HAPE-s) subjects with a history of HAPE, and 55 healthy climbers with HAPE resistance (HAPE-r). INTERVENTIONS: Twenty-one of 49 HAPE-s subjects underwent right cardiac catheterization. MEASUREMENTS AND RESULTS: The insertion/deletion polymorphism in the ACE gene (ACE-I/D) was investigated by polymerase chain reaction (PCR). There was no significant difference of the distribution of the ACE-I/D polymorphism between the HAPE-s and HAPE-r groups. The A(1166)C and G(1517)T single-nucleotide polymorphisms (SNPs) in AT(1)R gene were investigated by the PCR following digested by corresponding restricted endonuclease enzymes. The distribution of the G(1517)T SNP was significantly different between the two groups (p = 0.012). The pulmonary hemodynamics of the 21 HAPE-s subjects were retrospectively examined. The pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR), and PVR index (PVRI) were all significantly increased on hospital admission. Moreover, the PVR and PVRI were significantly higher in the HAPE-s subjects with D positivity than in the HAPE-s subjects with I positivity (PVR, p = 0.015; PVRI, p = 0.028), while the PAP did not show any significant difference between the two subgroups. CONCLUSIONS: The ACE-I/D polymorphism is not associated with HAPE susceptibility in Japanese subjects. The AT(1)R gene polymorphisms may likely associate with HAPE susceptibility. The D allele of the ACE-I/D polymorphism probably contributes to the hyperresponsive PVR and PVRI to acute hypoxia.

Adult↗
PubMed2004

Unusual characteristic patterns of postmortem injuries.

Animal scavenging is one of the most significant causes of postmortem injuries. A large variety of scavenging animals have been reported on in previous papers. Although postmortem injuries attributable to birds are well known in the case of "aerial burial," the custom in Tibet, few cases of bird scavenging have been reported. In the two cases discussed herein, postmortem injuries were attributed to crows. Both cases, shared characteristic patterns of postmortem injuries, and in both cases death was attributed to fire. Although massive tissue loss by the crow scavenging made it difficult to determine the cause of the death and rendered personal identification difficult, 1 mL of blood drawn from the intracranial cavity and DNA analysis enabled this information to be determined, albeit with some difficulty.

Aged↗
PubMed2003

Genetic polymorphism of the swine major histocompatibility complex ( SLA) class I genes, SLA-1, -2 and -3.

In order to identify and characterize genetic polymorphism of the swine major histocompatibility complex ( Mhc: SLA) class I genes, RT-PCR products of the second and third exons of the three SLA classical class I genes, SLA-1, SLA-2 and SLA-3 were subjected to nucleotide determination. These analyses allowed the identification of four, eight and seven alleles at the SLA-1, SLA-2 and SLA-3 loci, respectively, from three different breeds of miniature swine and one mixed breed. Among them, 12 alleles were novel. Construction of a phylogenetic tree using the nucleotide sequences of those 19 alleles indicated that the SLA-1 and -2 genes are more closely related to each other than to SLA-3. Selective forces operating at single amino acid sites of the SLA class I molecules were analyzed by the Adaptsite Package program. Ten positive selection sites were found at the putative antigen recognition sites (ARSs). Among the 14 positively selected sites observed in the human MHC ( HLA) classical class I molecules, eight corresponding positions in the SLA class I molecules were inferred as positively selected. On the other hand, four amino acids at the putative ARSs were identified as negatively selected in the SLA class I molecules. These results suggest that selective forces operating in the SLA class I molecules are almost similar to those of the HLA class I molecules, although several functional sites for antigen and cytotoxic T-lymphocyte recognition by the SLA class I molecules may be different from those of the HLA class I molecules.

Alleles↗
PubMed2003

A clinical feature associated with polymorphisms of the TNF region in Japanese patients with palmoplantar pustulosis.

We investigated the association of polymorphisms in the tumor necrosis factor (TNF) microsatellite as well as the promoter region of the TNFA gene and the TNFB gene with palmoplantar pustulosis (PPP). In order to clarify the heterogeneity of this disease, we performed a tonsillar provocation test on 78 patients and divided them into two groups according to the results; provocation positive (PP; n = 38) and provocation negative (PN; n = 40). We found that the phenotype frequency of the TNFB2 allele of the TNFB gene in the PN group was significantly higher than in controls (p = 0.0022, corrected p = 0.0044). There was also a significant increase in the frequency of allele B of the TNFA gene (TNFApB) in the PN group when compared with controls (p = 0.0049, corrected p = 0.025). Although there are no significant differences in the frequency of TNFa microsatellites, the frequency of the TNFd7 allele increased and that of the TNFd4 allele decreased in the PN group. An extended haplotype analysis revealed that the TNFd7-TNFApA-TNFB2 haplotype was more frequent in the PN group, implying that the PN group is associated with a low level of TNF-alpha production. These results indicate that detection of polymorphisms at the TNF locus may be a marker for determination of the heterogeneity of the disease, and that the allelic variation may influence the susceptibility.

Asian People↗
PubMed2003

Expansion of clonotype-restricted HLA-identical maternal CD4+ T cells in a patient with severe combined immunodeficiency and a homozygous mutation in the Artemis gene.

We have observed a male infant with severe combined immunodeficiency (SCID) responsible for Artemis gene mutation, in whom marked expansion of the transplacentally grafted maternal CD4(+) T cells was observed in various tissues. His class I and II major histocompatibility antigens (MHC) were identical to his mother's. We analyzed the T-cell populations within target tissues at a molecular level in order to determine whether different T-cell clonotypes are expanded in different types of tissue. Prior to T-cell expansion, the T-cell receptor variable beta (TCRBV) 5.1 subfamily predominated in peripheral blood (PB) lymphocytes. Third complementarity determining region (CDR3) size spectratyping and amino acid sequencing showed that the range of T-cell clonotypes was very restricted. After T-cell expansion, different TCRBV subfamilies were found to predominate in different target tissues; these included TCRBV 5.1 and 17 in the PB, TCRBV 13 and 21.3 in the bone marrow, and TCRBV 17 in lymph nodes. CDR3 size analysis showed that the expression of different proliferating T-cell clonotypes remained restricted after T-cell expansion. These results indicate that highly restricted maternal T-cell clonotypes can markedly expand, possibly in response to tissue-specific antigens, in a MHC-identical recipient.

Amino Acid Sequence↗
PubMed2003

Lymphoproliferative disease of granular lymphocytes with T-cell receptor gamma delta-positive phenotype: restricted usage of T-cell receptor gamma and delta subunit genes.

Lymphoproliferative disease of granular lymphocytes (LDGL) is characterized by more than 0.5 x 109/L of proliferating granular lymphocytes in the peripheral blood. Because of its rarity, the characteristics of LDGL with T-cell receptor (TCR) gammadelta phenotype (gammadeltaT-LDGL) have not yet been identified. This report describes the clinical, hematological, and immunological findings of four patients with this disease. In two cases, the clinical course was indolent and the other two patients required various therapies. The cells had a common immunophenotype: CD3+, CD4-, CD16+, CD56-, CD57-, CD122-, TCR-gammadelta+, and three were CD8-positive. The immunopurified TCR-gammadelta cells from the patients expressed only Vgamma9 and Vdelta1. Spectratyping and sequencing showed mono- or oligoclonality for TCRgamma and TCRdelta subunit genes. Soluble Fas ligand in sera was significantly elevated in all patients. These findings suggest that gammadeltaT-LDGL qualifies as a distinct disease entity.

Adult↗
PubMed2003

Serologic analysis of three cases of neonatal alloimmune thrombocytopenia associated with HLA antibodies.

BACKGROUND: Neonatal alloimmune thrombocytopenia (NAIT) is caused when maternal alloantibodies react with paternally inherited antigens present on the fetal PLTs, a reaction mainly due to antibodies against human PLT antigens. Cases in which NAIT has been caused by HLA antibodies are relatively rare. In this study, three cases of NAIT associated with HLA antibodies that occurred in a 1-year period are reported. STUDY DESIGN AND METHODS: The presence of HLA antibodies in these three NAIT case studies was elucidated by examining reactions of the neonatal and maternal sera with lymphocytes, PLTs, and beads from an HLA antibody screening test (FlowPRA, One Lambda Inc.). Absorption and elution tests with paternal cells were also conducted. In addition, the influence of titer and specificity of HLA antibodies on NAIT was analyzed in light of 24 other documented cases in Japan. RESULTS: In the three case studies presented herein, antibodies against human PLT antigens were found in neither the maternal nor neonatal sera, while specific HLA antibodies were identified in both sera. Absorption of maternal serum with paternal PLTs eliminated the reactivity against paternal PLTs and lymphocytes. CONCLUSION: Transplacental passage of maternal HLA antibodies was observed in the three neonates cited in the present study.

Adsorption↗
PubMed2003

Polymorphisms of the tyrosine hydroxylase gene in subjects susceptible to high-altitude pulmonary edema.

STUDY OBJECTIVES: A blunted hypoxic ventilatory response (HVR) has been observed in some sufferers of high-altitude pulmonary edema (HAPE), and was proposed as a potential mechanism in its pathogenesis. Tyrosine hydroxylase (TH) is a rate-limiting enzyme in the carotid body responding to hypoxia to synthesize dopamine neurotransmitter to heighten ventilation. The association of constitutional susceptibility to HAPE regarding the blunted HVR aspect with polymorphisms of the TH gene was examined. DESIGN: A cross-sectional case control study. SETTING: Shinshu University Hospital, Matsumoto, Japan. PARTICIPANTS: Forty-three subjects with a history of HAPE (HAPE group) and 51 healthy climbers without a history of HAPE (control group). MEASUREMENTS: The (TCAT)n tetranucleotide microsatellite repeats within intron 1 and Met81Val variant in exon 2 of the TH gene were investigated by polymerase chain reaction following either direct sequencing or restriction fragment length polymorphism. The HVR in 21 subjects among the HAPE group was also measured. RESULTS: No significant frequency differences could be found in terms of either of the two polymorphisms between the HAPE and control groups. Meanwhile, no relationships were observed between the HVR values of HAPE subjects and the individual alleles in both polymorphisms of the TH gene. CONCLUSION: The genetic susceptibility of HAPE, specifically the blunted HVR in HAPE, is probably not associated with the mutations of the TH gene, implying that these two polymorphisms may not be a sufficient genetic marker for predicting a predisposition to the susceptibility to HAPE.

Adolescent↗
PubMed2003

Human amnion-isolated cells normalize blood glucose in streptozotocin-induced diabetic mice.

Whole pancreas or beta-cell transplantation has opened the way for the treatment of advanced stage of diabetes mellitus. However, it is always limited by the scarcity of transplantation materials. The amniotic membrane is part of the fetal membrane and is composed of amniotic epithelium (HAE) and mesenchymal (HAM) cells that are derived from the inner cell mass in the blastocyst. Thus, HAE and HAM cells may have the potential to differentiate into various organs. The aim of our study was to assess the possibility of HAE cells differentiating into insulin-producing cells. In vitro, HAE cells stimulated with nicotinamide induced insulin mRNA in the culture cells. In vivo, HAE cells were capable of normalizing the blood glucose level of diabetic mice after several weeks of implantation into streptozotocin-induced diabetic mice. The distribution of human cells and human insulin secretion in mouse tissue studied by immunohistochemistry for anti-human-specific beta-2-microglobulin and anti-human-specific insulin shows the same location in mouse tissue. These studies suggest that HAE cells have the potential to differentiate into beta-cells in vivo, and hence that HAE cells have therapeutic potential for the treatment of type I diabetes mellitus.

Amniotic Fluid↗
PubMed2002

Identification of I kappa BL as the second major histocompatibility complex-linked susceptibility locus for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease with a complex etiology in which environmental factors within a genetically susceptible host maneuver the innate and adaptive arms of the immune system toward recognition of autoantigens. This ultimately leads to joint destruction and clinical symptomatology. Despite the identification of a number of disease-susceptibility regions across the genome, RA's major genetic linkage remains with the major histocompatibility complex (MHC), which contains not only the key immune-response class I and class II genes but also a host of other loci, some with potential immunological relevance. Inside the MHC itself, the sole consistent RA association is that with HLA-DRB1, although this does not encode all MHC-related susceptibility. Indeed, in a set of Japanese patients with RA and a control group, we previously reported the presence of a second RA-susceptibility gene within the telomeric human leukocyte antigen (HLA) class III region. Using microsatellites, we narrowed the susceptibility region to 70 kb telomeric of the TNF cluster, known to harbor four expressed genes (I kappa BL, ATP6G, BAT1, and MICB). Here, using numerous single-nucleotide polymorphisms (SNPs) and insertion/deletion polymorphisms, we identify the second RA-susceptibility locus within the HLA region, as the T allele of SNP 96452 (T/A), in the promoter region (position -62) of the I kappa BL gene (P=.0062). This -62T/A SNP disrupts the putative binding motif for the transcriptional repressor, delta EF1, and hence may influence the transcription of I kappa BL, homologous to I kappa B alpha, the latter being a known inhibitor of NF kappa B, which is central to innate immunity. Therefore, the MHC may harbor RA genetic determinants affecting the innate and adaptive arms of the immune system.

Alleles↗
PubMed2002

Positive association of the endothelial nitric oxide synthase gene polymorphisms with high-altitude pulmonary edema.

BACKGROUND: A defect of nitric oxide (NO) synthesis in the lung of high-altitude pulmonary edema (HAPE) has been suggested to contribute to its exaggerated pulmonary hypertension. Several polymorphisms have been identified in the gene encoding endothelial nitric oxide synthase (eNOS), which is a key enzyme responsible for NO synthesis, some of which were reported to be associated with vascular disorders. METHODS AND RESULTS: We studied 41 HAPE-susceptible subjects (HAPE-s) and 51 healthy climbers (control group) in a Japanese population. We examined 2 polymorphisms of the eNOS gene, including the Glu298Asp variant and 27-base pair (bp) variable numbers of tandem repeats using polymerase chain reaction followed by restriction fragment length polymorphism. The Asp allelic frequency of the Glu298Asp variant was 25.6% in the HAPE-s and 9.8% in the controls, which was significantly different between the two groups (P=0.0044). The eNOS4a allelic frequency of 27-bp variable numbers of tandem repeats was 23.2% in the HAPE-s, significantly higher than that of 6.9% in the controls (P=0.0016). In HAPE-s group, 11 of 41 (26.8%) subjects possessed simultaneously both of the two significant alleles, but among the controls, none did, which showed a high statistical difference between the two groups (P=0.000059). CONCLUSIONS: Both polymorphisms of the eNOS gene were significantly associated with HAPE. A genetic background may underlie the impaired NO synthesis in the pulmonary circulation of HAPE-s. These polymorphisms could be genetic markers for predicting the susceptibility to HAPE.

Adolescent↗
PubMed2002

Susceptibility gene for non-obstructive azoospermia located near HLA-DR and -DQ loci in the HLA class II region.

The technical developments and expanded indications for testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) provide great advantages for patients with non-obstructive azoospermia. Such success, however, also means that genetic abnormalities in non-obstructive azoospermia can be transmitted to the next generation, demonstrating the importance of being able to understand the genetic background of non-obstructive azoospermia. We have previously reported that human leukocyte antigens (HLA)-A33 and -B44 in the HLA class I region and the HLA-DRB1*1302 allele in the HLA class II region are linked to susceptibility to non-obstructive azoospermia in Japanese men. However, strong linkage of HLA-DRB1*1302 with HLA-A33 and -B44 is also evident in the Japanese population. Thus, uncertainty prevails as to whether the HLA class I or class II molecule is more directly associated with non-obstructive azoospermia. In the present study, we performed association analysis with 21 polymorphic microsatellite markers identified near the HLA genes to map the gene involved in the development of non-obstructive azoospermia more precisely. Microsatellite markers located in the HLA class I region or the class III region showed no statistically significant association with this disorder, although once again the HLA-A33 and -B44 alleles showed a significant association. In contrast, some of the microsatellite markers in the HLA class II region and at the HLA-DRB1 and -DQB1 loci displayed strong associations with non-obstructive azoospermia. Taken together, our previous and present data suggest that the critical region for development of non-obstructive azoospermia is near the HLA-DRB1 and -DQB1 segments in the HLA class II region.

Asian People↗
PubMed2002

Multiplex short tandem repeat typing in degraded samples using newly designed primers for the TH01, TPOX, CSF1PO, and vWA loci.

We performed multiplex polymerase chain reaction (PCR) for the TH01, TPOX, CSF1PO, and vWA loci using a newly designed pair of primers that yield smaller fragments than reported previously [Fujii et al., J Hum Genet 45 (2000) 303; Lederer et al., Int J Legal Med 114 (2000) 87]. These loci can be detected in the range of 74-143 bp amplifying products. This system required genomic DNA in a range of 80 pg to 2 ng, and proved to be a sensitive typing method. We compared our system against the GenePrint Fluorescent STR Multiplex Systems CTTv (Promega, Madison, WI, USA), using DNA extracted from old bloodstains left to stand for 17-26 years at room temperature. With our designed system, all allele-typing efforts were successful in the range of 1-5 ng DNA, while no signal peaks were detected, even with when using 10 ng of DNA GenePrint Fluorescent STR Multiplex Systems CTTv.

Journal Article↗
PubMed2002

DNA microarray analysis of T cell-type lymphoproliferative disease of granular lymphocytes.

Lymphoproliferative disease of granular lymphocytes (LDGL) is characterized by the clonal proliferation of large granular lymphocytes of either T- or natural killer cell origin. To better understand the nature of T cell-type LDGL, we purified the CD4-CD8+ proliferative fractions from LDGL patients (n=4) and the surface marker-matched T cells isolated from healthy volunteers (n=4), and compared the expression profiles of 3456 genes using DNA microarray. Through this analysis, we identified a total of six genes whose expression was active in the LDGL T cells, but silent in the normal ones. Interestingly, expression of the gene for interleukin (IL) 1beta was specific to LDGL T cells, which was further confirmed by the examination of the serum level of IL-1beta protein. Given its important role in inflammatory reactions, the disease-specific expression of IL-1beta may have a causative relationship with the LDGL-associated rheumatoid arthritis. Spectratyping analysis of the T-cell receptor repertoire also proved the monoclonal or oligoclonal nature of LDGL cells. These data have shown that microarray analysis with a purified T-cell subset is an efficient approach to investigate the pathological condition of Tcell-type LDGL.

Adult↗
PubMed2002

Platelet transfusion refractoriness caused by a mismatch in HLA-C antigens.

BACKGROUND: HLA-C antigens have been thought to be of little significance in determining the efficacy of platelet transfusions. However, six alloimmunized patients were encountered who were refractory to platelet transfusions because of anti-HLA-Cw3, -Cw3, -Cw7, or -Cw8. STUDY DESIGN AND METHODS: Between 1995 and the present, 88 patients with hematologic malignancies became refractory to random-donor platelet transfusions due to HLA antibodies. HLA-A- and HLA-B-compatible platelet transfusions were successful in boosting platelet levels with 82 of the patients. This study concerns the remaining six HLA-immunized patients who were refractory to HLA-A- and HLA-B-compatible platelet transfusions. The response to the platelet transfusions was assessed by calculating both 1- and 24-hour posttransfusion CCIs for each transfusion. RESULTS: The average CCI(1 hour) and CCI(24 hours) in all patients were 20.0 and 12.8 for HLA-A-, HLA-B-, and HLA-C-compatible transfusions and were 1.4 and 1.2 for HLA-A- and HLA-B-compatible but HLA-C-incompatible transfusions, respectively (p < 0.001). CONCLUSION: These findings clearly indicate that matching of the HLA-C antigens is also required in some alloimmunized patients to obtain the effectiveness of platelet transfusions.

Adolescent↗