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Biomedical subjects

A Wakisaka

Publications and source records attributed to A Wakisaka.

At least 55 records · Page 3Linked to original sources
PubMed1995

CAG repeat expansion of Machado-Joseph disease in the Japanese: analysis of the repeat instability for parental transmission, and correlation with disease phenotype.

Machado-Joseph disease (MJD) is caused by abnormal expansion of an unstable CAG repeat in a novel gene locating on chromosome 14q32.1. We analysed this CAG repeat polymorphism with 66 Japanese MJD patients. All the patients were selectively associated with abnormal expansion of the CAG repeat. Repeat length of the mutant allele did not overlap that of normal allele and closely correlated with not only age at onset but also with clinical phenotypes. CAG repeat size is apparently related to a wide variety of phenotypic presentations in MJD.

Adult↗
PubMed1995

Expression of endogenous retroviruses, ERV3 and lambda 4-1, in synovial tissues from patients with rheumatoid arthritis.

We addressed the question of whether or not expression of human endogenous retroviruses (ERV), ERV3 and lambda 4-1, is related to the pathogenesis of rheumatoid arthritis (RA). In genomic Southern hybridization, there were no significant differences between RA patients and healthy volunteers with regard to frequencies of restriction fragment length polymorphism (RFLP) patterns, for either ERV3 or lambda 4-1. By Northern blot analysis using fresh synovial tissues, cultured synovial cells, and peripheral blood mononuclear cells (PBMC) from patients with RA, we noted two molecular species of ERV3 mRNAs of 3.5 kb and 9.0 kb sizes, and one single molecular species of lambda 4-1 mRNAs of 4.2 kb size. The expression was detected not only in RA patients but also in synovial cells from osteoarthritis (OA) as a non-RA control and PBMC from healthy volunteers, and was not related to RA activities or treatments. Although ERV3 and lambda 4-1 expression may not be directly associated with the pathogenic pathway of RA, the possibility exists that human ERV may have a causative role in autoimmune diseases, including RA. We also examined the effect of cytokines on the transcriptional regulation of ERV3. Although the level of ERV3 expression in cultured synovial cells did not change with IL-1 beta treatment, the level for cultured proximal tubular epithelial cells (hKEC) was up-regulated.

Arthritis, Rheumatoid↗
PubMed1995

Spinocerebellar ataxia 1 (SCA1) in the Japanese in Hokkaido may derive from a single common ancestry.

Spinocerebellar ataxia 1 (SCA1) is caused by expansion of an unstable CAG triplet repeat located on the short arm of chromosome 6. Precise mapping has shown a positional relationship to closely linked markers in the order of D6S109-D6S274-D6S288-SCA1-AM10GA-D6S89+ ++-EDN1 from centromere to telomere. The haplotype which cosegregated with the disease was determined in 12 Japanese pedigrees with SCA1. Although the alleles of the SCA1 haplotype varied from pedigree to pedigree, depending on the distance from the SCA1 locus, the affected and presymptomatic subjects carried the same alleles at D6S288 and D6S274. All the families with SCA1 had migrated from either Miyagi or Yamagata Prefectures, neighbouring areas in the Tohoku District, the northern part of Honshu which is the main island of Japan. It seems highly likely that SCA1 in the Japanese, at least those residing in Hokkaido, derives from a single common ancestry.

Chromosome Mapping↗
PubMed1995

Mapping of the gene for Machado-Joseph disease within a 3.6-cM interval flanked by D14S291/D14S280 and D14S81, on the basis of studies of linkage and linkage disequilibrium in 24 Japanese families.

The gene locus of Machado-Joseph disease (MJD) has recently been mapped within a 29-cM subregion of 14q chromosome. We did a linkage study of 24 multigenerational MJD Japanese pedigrees, in an attempt to narrow the candidate region of this gene. Pairwise and multipoint linkage analysis, together with haplotype segregation analysis, led to the conclusion that the MJD gene is located at the 6.8-cM interval between D14S256 and D14S81 (Zmax = 24.78, multipoint linkage analysis). D14S291 and D14S280, located at the center of this interval, showed no obligate recombination with the MJD gene (Zmax = 5.93 for D14S291 and 9.99 for D14S280). A weak, but significant, linkage disequilibrium of MJD gene was noted with D14S81 (P < .05) but not with D14S291 or D14S280. These results suggest that a 3.6-cM interval flanked by D14S291/D14S280 and D14S81 is the most likely location of the MJD gene and that it is closest to D14S81.

Adult↗
PubMed1994

Genetic heterogeneity of dominantly inherited olivopontocerebellar atrophy (OPCA) in the Japanese: linkage study of two pedigrees and evidence for the disease locus on chromosome 12q (SCA2).

We did a linkage study of 2 multigenerational pedigrees with dominant olivopontocerebellar atrophy (OPCA) other than SCA1, with chromosome 12q microsatellites. Multipoint linkage analysis led to the conclusion that the disease locus locates within the 6.2 cM interval between IGF1 and D12S84/D12S105. This result coincides with that of Cuban ataxia pedigrees designated as SCA2. Our study provides genetic evidence that dominant OPCA in the Japanese consists of at least two genetically different disorders; SCA1 and SCA2.

Adolescent↗
PubMed1994

Analysis of restriction fragment length polymorphism for the HLA-DR gene in Japanese patients with sarcoidosis.

BACKGROUND: It is commonly assumed that some immunological disorder may play a part in the pathogenesis of sarcoidosis. Previous studies by several groups have shown a significant association with HLA-DR antigens in patients with sarcoidosis. In this study, restriction fragment length polymorphism (RFLP) analysis of the HLA-DR gene was designed to confirm the association at the gene level and to look for a gene rearrangement which may influence susceptibility to sarcoidosis. METHODS: Thirty two unrelated Japanese patients with sarcoidosis were tested for HLA antigens and subjected to RFLP analysis after digestion with Eco RI, Pst I, Bam HI, Pvu II, and Hind III by using an HLA-DR beta cDNA probe. A group of 47 unrelated healthy Japanese subjects served as controls. Frequencies of each restriction fragment were compared between the patients and the control subjects. Correlation between fragment frequencies and clinical features were also analysed. RESULTS: No restriction fragments of HLA-DR beta gene were found specific to the patients with sarcoidosis. The RFLP analysis could detect polymorphism of HLA-DR beta genes that was not distinguishable by conventional serological methods. Several restriction fragments of the DR beta gene were seen only in DRw52 positive individuals, and showed higher frequencies in the patients than in control subjects. The patients with these DNA fragments were likely to have limited stage disease with no ophthalmic involvement. CONCLUSIONS: An association between HLA and sarcoidosis was noted at the DNA level, although no restriction fragments were specific for this disease. RFLP analysis of the HLA gene is a more useful method than the usual HLA typing, and should be the first step in identifying the gene sequence which is connected with susceptibility to sarcoidosis.

Adolescent↗
PubMed1994

Deficiency of the fourth component of complement (C4): a family case.

In this report, an apparently healthy 38-year-old woman with a remarkably low serum C4 value is described together with other family members who had moderately low serum C4. Plasma C4 typing disclosed that the proband inherited two C4B "null" haplotypes. In addition, Southern blot analysis of the C4 gene indicated that the C4A gene was partially deleted on one of these two haplotypes in the proband. We thus concluded that a de novo deletion on the inherited half-null haplotype was the likeliest cause of the low C4 level.

Adult↗
PubMed1993

A linkage study with DNA markers (D4S95, D4S115, and D4S111) in Japanese Huntington disease families.

Attempts to isolate the Huntington disease (HD) gene based on its position have been frustrated by apparently contradictory recombination events in HD pedigrees that have predicted two non-overlapping candidate regions: 100 kb at the telomere of the short arm of chromosome 4, and a 2.2 Mb region located internally at 4p16.3. The proximal location is also supported by the detection of a linkage disequilibrium between HD and some restriction fragment length polymorphisms (RFLPs) at the D4S95, D4S98, and D4S127 loci. In the present study, a proximal marker D4S95 showed tight linkage to the disease locus in Japanese pedigrees (Zmax = 3.31, theta max = 0.00), while distal markers D4S115 and D4S111 did not. Particularly, a two point linkage analysis between D4S111 and HD yielded a lod score -2.01 for theta = 0.015. This result leads to the exclusion, as a possible region of localization of the HD gene, of more than 3 cM of the genome around D4S111 locus. At the same time our results favor aforementioned proximal location as a candidate location for the HD gene.

Adult↗
PubMed1993

Heterogeneity of HLA-G genes identified by polymerase chain reaction/single strand conformational polymorphism (PCR/SSCP).

A genomic HLA-G clone named 7.0E was isolated from a Japanese placenta. The deduced amino acid sequence of the 7.0E was identical to two HLA-G genomic clones and two cDNA clones previously described. The DNA sequences of alpha 1 and alpha 2 domains of the HLA-G gene from 5 cell lines also encoded the same amino acids. However, a 14 bp insertion, ATTTGTTCATGCCT, was present in the 3' untranslated region of 7.0E compared with the originally described HLA-G clone (HLA 6.0). Polymerase chain reaction (PCR)/single strand conformational polymorphism (SSCP) analysis of exon 8 allowed the HLA-G gene to be classified into two alternative types, G6.0 and 7.0 E, those correlated to the absence or the presence of the 14 bp stretch. Each group had minor sequence variant(s), and the alleles of the 7.0E-type were more heterogeneous than those of the G6.0-type. The 14 bp deletion is present only in the G6.0-type of HLA-G alleles among HLA class I genes. Thus it was suggested that G6.0 alleles were generated after diversification of the HLA-G.

Alleles↗
PubMed1993

[Spinocerebellar ataxia 1--clinical study of 17 patients in a large pedigree].

We studied a large pedigree with dominant spinocerebellar ataxia, genetically and clinically. At now, 27 members over 5 generations have been affected. Linkage study for the disease locus to D6S89 in a total of 44 individuals showed maximum lod scores of 3.99 at theta = 0.000. This result indicates that the disease locus of this pedigree locates near D6S89 on chromosome 6p (SCA 1). We studied 17 patients clinically. Mean age at onset was 37.7 +/- 8.6, and mean duration after onset was 11.3 +/- 6.8 years. Their clinical features were characterized by progressive ataxia, pyramidal involvement with hyperreflexia or spasticity, and mild posterior column involvement. Mild gaze nystagmus at early stage became unclear with the progress of illness. The frequent signs in the advanced stage were diffuse amyotropy, twitching of face or tongue, bulbar palsy, slow saccade, external ophthalmoparesis, mydriasis, coarse postural tremor, and dementia with emotional disturbance. There are so much clinical similarities between our pedigree and other SCA 1 pedigrees in the literature. Generally, SCA 1 shows hyperreflexia, spasticity, and terminal slow saccade. On the other hand, non-SCA 1 type OPCA is characterized by progressive hyporeflexia, slow eye movement from early stage, and frequent choreoathetosis. Gaze nystagmus, external ophthalmoparesis, amyotrophy, and spasticity are common in both SCA 1 and Machado-Joseph disease (MJD). However, they are more frequent in MJD than SCA 1. Moreover, extrapyramidal signs, such as dystonia, are rare is SCA 1. Based on these difference, SCA 1 could be clinically differentiated from other similar hereditary ataxias.

Adult↗
PubMed1993

[Recent progress of research on hereditary spinocerebellar degeneration].

Hereditary spinocerebellar degeneration consist of a cluster of heterogenous disorders. Based on clinical features, neuropathological findings and inheritance mode, these disorders have been classified into several entities. In the Japanese, olivo-ponto-cerebellar atrophy (OPCA), Machado-Joseph disease (MJD) and dominant cortical cerebellar atrophy (CCA) are the most popular forms of ataxia. Recent linkage analyses have revealed the locations of these genes; OPCA maps either on 6p23 (SCA1) or on 12q23 (SCA2), and MJD on 14q. The chromosomal assignment of these genes has resulted in development of a new classification of ataxia and has opened a new era of ataxia research.

Chromosome Mapping↗
PubMed1992

A rat model of human T lymphocyte virus type I (HTLV-I) infection. 1. Humoral antibody response, provirus integration, and HTLV-I-associated myelopathy/tropical spastic paraparesis-like myelopathy in seronegative HTLV-I carrier rats.

Human T lymphocyte virus type I (HTLV-I) can be transmitted into several inbred strains of newborn and adult rats by inoculating newly established HTLV-I-immortalized rat T cell lines or the human T cell line MT-2. The transmission efficiency exceeds 80%, regardless of strain differences or the age at transmission. The production of anti-HTLV-I antibodies significantly differs among the strains and depends on the age at the time of transmission. Rats neonatally inoculated with HTLV-I-positive rat or human cells generally become seronegative HTLV-I carriers throughout their lives, whereas adult rats inoculated with HTLV-I-positive cells at 16 wk of age become seropositive HTLV-I carriers. The HTLV-I provirus genome is present in almost all organs, regardless of whether the carriers are seronegative or seropositive. According to antibody titers to HTLV-I, there are three groups of inbred rat strains: ACI, F344, and SDJ (high responders); WKA, BUF, and LEJ (intermediate responders); and LEW (low responder). Three of three 16-mo-old seronegative HTLV-I carrier rats of the WKA strain developed spastic paraparesis of the hind legs. Neuropathological examinations revealed that the lesions were confined primarily to the lateral and anterior funiculi of the spinal cord. Both myelin and axons were extensively damaged in a symmetrical fashion, and infiltration with massive foamy macrophages was evident. The most severe lesions were at levels of the thoracic cord and continued from the cervical to the lumbar area. These histopathological features as well as clinical symptoms largely parallel findings in humans with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). These HTLV-I carrier rats, in particular the WKA rats described above, can serve as a useful animal model for investigating virus-host interactions in the etiopathogenesis of HTLV-I-related immunological diseases, particularly HAM/TSP.

Aging↗
PubMed1992

Molecular analysis of a HTLV-IpX defective human adult T-cell leukemia.

Fresh and cultured leukemia cells from an adult T-cell leukemia (ATL) patient which possessed gag and env gene defective human T-cell leukemia virus type I (HTLV-I) provirus genome were molecularly analyzed. Cells from both fresh and the established cell line, named KB-1 showed identical surface markers of helper T cells, expressed the interleukin 2 (IL-2) receptor and had an identical defective HTLV-I provirus genome with deletions of the gag and env genes involving pX gene exon 2. The KB-1 cells grew vigorously in vitro, even in the absence of IL-2 and the culture supernatant of KB-1 contained a large amount of IL-2. Neither pX mRNA nor p40(TAX) protein was detected in the KB-1 cells. The collective evidence suggests that the pX gene was not functioning in this particular ATL case. The biological function of the HTLV-I genes, especially the pX gene is discussed in relation to the early and late leukemogenesis of ATL.

Blotting, Southern↗
PubMed1992

Development of a flow-cytometric HLA-A locus mutation assay for human peripheral blood lymphocytes.

A flow-cytometric technique was developed to measure the frequency of variant lymphocytes lacking expression of HLA-A2 or A24 allele products among donors heterozygous for HLA-A2 or A24. It was found that the variant frequency of lymphocytes in peripheral blood was of the order of 10(-4) and increased with donor age. Molecular analyses of mutant clones revealed that about one-third were derived from somatic recombinations and that the remaining two-thirds did not show any alterations after Southern blotting analysis. In contrast, mutants obtained after in vitro X-ray mutagenesis study were found to be mostly derived from large chromosomal deletions. A small-scale study on atomic bomb survivors did not show a significant dose effect.

Adult↗
PubMed1992

A simple method for gender verification based on PCR detection of Y-chromosomal DNA and its application at the Winter Universiade 1991 in Sapporo City, Japan.

A simple and reliable screening method for gender verification at international sports competitions was developed on the basis of detection of Y-chromosomal DNA which was specifically amplified by polymerase chain reaction (PCR). Total DNA obtained from buccal mucous membrane cells by digestion with proteinase K followed by boiling treatment was directly used for the PCR. The amplified product was electrophoresed on an agarose gel staining with ethidium bromide. We adopted three sets of the PCR primer, identifying different regions of Y-chromosome, of which sensitivity and specificity were preliminary evaluated for 228 (112 male, 116 female) DNA samples from lymphocytes. This new method was first applied for the gender verification test at the Winter Universiade 1991 Sapporo, accompanied by traditional microscopic tests for X- and Y-chromatins. No positive results were obtained for 155 female competitors using both the PCR and the microscopic methods. The superiority of the proposed method was clearly shown in the reliability of the results and also in the saving on instrumental and personnel costs as compared to previous cytologic methods.

DNA↗
PubMed1992

[Extrapyramidal manifestations in hereditary olivopontocerebellar atrophy--clinical study of 10 cases in three affected pedigrees].

We studied 3 pedigrees affected with autosomal dominant olivopontocerebellar atrophy (OPCA), and clinical features of 10 patients were reported. Clinically, 6 cases were dominated with cerebellar ataxia, one with Parkinsonism, and three with choreiform movements. Furthermore, they were characterized by slow eye movement and progressive loss of tendon reflexes. Generally, extrapyramidal manifestations, such as Parkinsonism or choreiform movements, are occasionally observed in dominant OPCA. However, the pathogeneses are different from each other. The choreiform movements are unique in dominant OPCA, and generally not observed in sporadic OPCA. In the distribution of degenerated foci, dominant OPCA is often associated with degeneration of not only substantia nigra, but also with other structures such as dentate nucleus, red nucleus, external segment of globus pallidus (GPe), and subthalamic nucleus. This dentatorubral and pallido-Luysian system degeneration are parts of neuropathological findings in hereditary DRPLA (Naito-Oyanagi form). In both disorders, choreiform movements is observed. Current theory indicates that hyperactivity of neostriatal dopamine neurons and degeneration of GPe play roles in the pathogenesis of chorea. Clinically, choreiform movements are common in hereditary DRPLA, but not in dominant OPCA. This difference could be explained by the nigral degeneration in dominant OPCA, which suppress the generation of choreiform movements.

Adult↗