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Biomedical subjects

S Kuwata

Publications and source records attributed to S Kuwata.

At least 37 records · Page 2Linked to original sources

A search for a mutation in the tumour necrosis factor-alpha gene in narcolepsy.

The discovery of almost 100% association of narcolepsy with human leukocyte antigens (HLA) DR2 antigen prompted molecular biological research of this disorder. In the HLA class II gene cluster, the gene for tumour necrosis factor-alpha (TNF-alpha), which plays a role in the regulation of normal human sleep, is located. The present study searched for a mutation in the TNF-alpha gene by single-strand conformation polymorphism analysis (SSCP) in patients with narcolepsy. No mutation was detected in exons and introns of the TNF-alpha gene by SSCP and sequencing.

DNA Mutational Analysis↗

Characteristics of cardiovascular morphology and function in the high-normal subset of hypertension defined by JNC-VI recommendations.

A cross-sectional study was conducted to compare the morphological and functional characteristics of the cardiovascular system among subgroups of hypertension defined by the JNC-VI recommendations. One hundred and sixteen subjects (normotensives and unmedicated hypertensives: 49+/-10 yr) were classified into 4 groups based on the criteria of JNC-VI: normotensive (NOR: n = 38), high-normal blood pressure (HN: n = 16), stage 1 hypertensive (SI: n = 28), and stage 2 to 3 hypertensive (SII-III: n = 34). Ultrasonographic examinations of the heart and carotid artery were performed in all subjects, and the following parameters were obtained: left ventricular mass index (LVMI), relative wall thickness at end-diastole (RWTd), cardiac diastolic function (A/E), common carotid artery diameter (CAD), intimal media thickness of the common carotid artery (IMT), and distensibility of the common carotid artery (Distens). RWTd, A/E, and IMT in SI (RWTd, 0.41+/-0.07; A/E, 1.21+/-0.41; IMT, 0.69+/-0.17 mm) and SII-III patients (0.40+/-0.08, 1.38+/-0.33, 0.80+/-0.21 mm) were larger than those in NOR patients (0.33+/-0.03, 0.86+/-0.21, 0.56+/-0.10 mm) (p < .01). Furthermore, LVMI in SII-III (135.5+/-35.5 g/m2) patients was larger than that in NOR patients (99.4+/-17.5 g/m2) (p < .05). RWTd in HN patients (0.37+/-0.06) was significantly higher than that in NOR patients (p < .05). A/E tended to be larger in HN than in NOR patients (p < 0.1). In the normotensives, no significant difference in any of the parameters was detected between those with optimal (n = 19) and normal (n = 19) blood pressure. Thus, both morphological and functional changes were associated with elevation of blood pressure. Cardiac morphological adaptation and functional impairment were present even in subjects with high-normal blood pressure level, while there were no significant differences between the normal and optimal subsets.

Adult↗

Precore wild-type DNA and immune complexes persist in chronic hepatitis B after seroconversion: no association between genome conversion and seroconversion.

Precore hepatitis B virus (HBV) mutants may gradually prevail during or after seroconversion (SC) from hepatitis B e antigen (HBeAg) to hepatitis B e antigen antibody (anti-HBe) status in many chronic hepatitis B (CH-B) patients. However, patients with CH-B still produce anti-HBe more than several years after SC, and the relationship between SC and genome conversion in the precore region has not been clarified. Therefore, in patients with CH-B who had a sustained loss of HBeAg and complete remission of hepatitis after SC, the precore region was sequenced in paired serum samples from 1 year before SC to 3 years after SC. Mutant precore defective HBV DNA was found in only 6 (19%) of 31 CH-B patients who had a complete remission of hepatitis after SC. Mixed-type HBV DNA (precore wild-type and mutant-type) was found in 4 (13%) patients. Wild-type HBV DNA was found in 21 (68%) CH-B patients after SC. Longer-term follow-up of 11 CH-B patients indicated that 3 of 11 patients experienced precore genome conversion 2 to 3 years after SC. E-plus DNA or e-minus DNA was semiquantitated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays before and after SC. E-plus DNA levels decreased from 10(5.56+/-1.58) to 10(2.45+/-1.61). Similarly, e-minus DNA levels declined from 10(4.25+/-1.56) to 10(1.86+/-1.37). By dot-blot assay, serum HBV DNA became negative soon after SC, as did serum HBeAg. In contrast, HBeAg-containing immune complexes were still detected after SC. Anti-HBe antibody was produced throughout SC and thereafter, as determined by a sensitive experimental assay. Therefore, we conclude that genome-conversion in the precore region is a separate event from HBeAg/anti-HBe seroconversion.

Acute Disease↗

Involvement of cucumber mosaic cucumovirus RNA2 and RNA3 in viral systemic spread in radish plant.

The genetics of cucumber mosaic cucumovirus (CMV) and the pathogenicity of the virus for Raphanus sativus were analyzed using pseudorecombinants constructed from the infectious transcripts of two naturally occurring strains of cucumber mosaic cucumovirus (CMV-D8 and CMV-Y). CMV-D8, but not CMV-Y, could cause systemic infection of the plant. Viral accumulation and systemic movement in the plants was examined using immuno-tissue blot analysis, dot blot and Northern blot hybridization. Virus was equally distributed and CMV RNAs accumulated to similar levels in the inoculated cotyledons of radish irrespective of the pseudorecombinant, suggesting that there are no apparent differences in the ability of infection and viral accumulation between CMV-D8 and CMV-Y. We found, however, that both RNAs 2 and 3 of CMV-D8 are involved in determining the efficiency for the systemic infection of R. sativus. Co-operated interactions between genetic information of RNAs 2 and 3 would control the efficient translocation of virus from the inoculated leaves to the uninoculated upper leaves of radish plant.

Blotting, Northern↗

Analysis of HLA class II and TAP alleles in Japanese patients with psoriasis vulgaris.

We investigated HLA class II and transporter associated with antigen processing (TAP) alleles in eighty-five unrelated Japanese patients with psoriasis vulgaris and fifty-two healthy controls using the polymerase chain reaction-restriction fragment length polymorphism method. The frequencies of DRB1*1502 and DQB1*0601 were increased in the patient group (DRB1*1502; 21% vs 12%, p < 0.05, DQB1*0601; 35% vs. 21%, p < 0.05), while the frequencies of DRB1*0406 and TAP2*E were decreased in the patients (DRB1*0406; 2% vs 9%, p < 0.05, TAP2*E; 4% vs 11%, p < 0.05). However, none of these remained significant after p values were corrected for the number of comparisons made (pc > 0.05). We also analysed specific amino acids on HLA class II molecules, but no significant difference was found between the two groups. Our previous reports clarified that aspartate at residue 9 (48% vs 20%, p < 0.002) and alanine at residue 73 (81% vs 48%, p < 0.0001) on HLA-C molecules were strongly associated with Japanese patients with PsV. These specific amino acids on HLA-C molecules are supposed to play more important roles compared with HLA class II and TAP alleles in the development of psoriasis vulgaris.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Deletion pattern of the steroid sulphatase gene in Japanese patients with X-linked ichthyosis.

Most caucasian patients with X-linked ichthyosis (XLI) reportedly display large genomic deletions involving the entire steroid sulphatase (STS) gene and flanking regions. In this study, we investigated the deletion patterns of the STS gene and flanking regions in 12 unrelated Japanese patients with XLI using the polymerase chain reaction method with 10 markers, including the 5' and 3' ends of the STS gene. Eleven of the 12 patients exhibited deletion of this entire gene, whereas the twelfth patient showed no evidence of deletion. In 10 of the 12 patients, the entire region from DXS1139 to DXF22S1 was deleted, the most common deletion pattern observed in caucasian patients, indicating that there are no racial or ethnic differences.

Adolescent↗

Polymorphisms of DMA and DMB genes in Japanese systemic lupus erythematosus.

Associations between polymorphisms of DMA and DMB alleles and systemic lupus erythematosus (SLE) were studied in 51 Japanese SLE patients and 77 normal subjects by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Phenotype frequencies of DMB*0101 tended to increase in SLE, but the difference was not significant (76.5% vs 70.1% in controls). The phenotype frequency of DMB*0103 was decreased in the SLE group, but the difference was not significant (49.0% vs 53.2%). Furthermore, there was no evidence of any association of either DMA or DMB alleles with HLA-DRB1*1501. The phenotype frequency of DMB*0101 was higher in the SLE group with anti-double-stranded DNA antibody (a-dsDNA) than in the SLE group without a-dsDNA, but the difference was not significant (P = 0.045, corrected P not significant). No other DMA or DMB alleles showed any associations in various immunological subgroups of SLE. These data suggest that neither the DMA nor the DMB gene determines susceptibility to SLE in Japanese.

Adult↗

Devices for structured data entry in electronic patient record.

Electronic patient record is expected to have edit, data analysis, and decision supporting functions. To realize these functions, the entered data should be structured. We made a template based data entry system with some devices. We defined a template for each describing unit, i.e., symptom, physical finding and examination report. Template is composed of several describing elements (a pair of property and value), which form tree structure in general. When a template is selected, the top layers of the elements are displayed at once allowing data entry. When the data qualified by other elements is entered then system presents the second layer about this data at once. This enables users to skip entering some unnecessary items. Users can constitute a form by combining some templates frequently used in a situation. Furthermore, at the second patient visit, the system can present the templates used in the former patient visit to check the different point. These templates and forms can be made easily by editing the master data using template master maintenance program. The entered patient data are presented in progress note and flow sheet. In progress note, the entered data are translated into natural language. In the flow sheet, representative data of each template are present in the cell of the matrix whose line indicates the describing unit and column indicates date. If the cell is clicked, then the details are presented. Using this system, we made templates and forms for cardiovascular field and entered the data about an actual patient with angina pectoris. The time taken by inputting data is shorter than that by handwriting and the content is enough for a patient record. This system is practical for structured data entry in electrical patient record.

Cardiovascular Diseases↗

Functional evaluation of telemedicine with super high definition images and B-ISDN.

In order to determine whether a super high definition (SHD) image running at a series of 2048 resolution x 2048 line x 60 frame/sec was capable of telemedicine, we established a filing system for medical images and two experiments for transmission of high quality images were performed. All images of various types, produced from one case of ischemic heart disease were digitized and registered into the filing system. Images consisted of plain chest x-ray, electrocardiogram, ultrasound cardiogram, cardiac scintigram, coronary angiogram, left ventriculogram and so on. All images were animated and totaled a number of 243. We prepared a graphic user interface (GUI) for image retrieval based on the medical events and modalities. Twenty one cardiac specialists evaluated quality of the SHD images to be somewhat poor compared to the original pictures but sufficient for making diagnoses, and effective as a tool for teaching and case study purposes. The system capability of simultaneously displaying several animated images was especially deemed effective in grasping comprehension of diagnosis. Efficient input methods and creating capacity of filing all produced images are future issue. Using B-ISDN network, the SHD file was prefetched to the servers at Kyoto University Hospital and BBCC (Bradband ISDN Business chance & Culture Creation) laboratory as an telemedicine experiment. Simultaneous video conference system, the control of image retrieval and pointing function made the teleconference successful in terms of high quality of medical images, quick response time and interactive data exchange.

Computer Communication Networks↗

Expression of plasma membrane water channel genes under water stress in Nicotiana excelsior.

Deduced amino acid sequences encoded by the cDNAs related to the MIP gene family from Nicotiana excelsior were characterized. Phylogenetic characterization of the products of corresponding genes named NeMip1, NeMip2, and NeMip3 strongly suggested that they are water channel proteins localized in the plasma membrane. Organ specificity of the gene expression was examined in leaves, roots, and reproductive organs. NeMip1 was expressed in roots and reproductive organs; however, it was hardly detectable in leaves. Two other genes, NeMip2 and NeMip3, were expressed in all of organs examined. mRNA accumulation from the genes was investigated in leaves under salt- and drought-stresses. The results demonstrated that mRNA accumulation from all three genes increased under salt- and drought-stresses within one day. However, they showed different accumulation patterns. In addition to their up-regulation under salt- and drought-stresses, daily changes in NeMip2 and NeMip3 mRNA accumulation was observed under unstressed conditions in leaves.

Amino Acid Sequence↗

Polymorphism of TAP1 and TAP2 in Japanese patients with rheumatoid arthritis.

Contribution of polymorphism of transporter associated with antigen processing 1 and 2 (TAP1 and 2) alleles to pathogenesis of Japanese rheumatoid arthritis (RA) was studied in 92 RA patients by PCR-RFLP. The allele frequency of TAP2A was slightly low (38.0%) and the frequencies of TAP2B and TAP2C were slightly high (39.7% and 17.9%) in RA, but these differences were not significant. These increases and decrease were due to the positive or negative associations with HLA-DRB1*0405. It was very likely that slight differences in TAP2A, TAP2B and TA2C in RA were secondary phenomenon reflecting an increase in HLA-DRB1*0405. The prevalence of TAP2E allele was low (3.3%, P < 0.01, Pc = not significant) and not correlated with HLA-DRB1*0405.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Association of DM genes in systemic sclerosis is secondary to the association with HLA genes.

The contribution of polymorphism of DMA and DMB alleles to the pathogenesis of Japanese Systemic Sclerosis (SSc) was studied in 55 Japanese SSc patients and 77 normal Japanese subjects using the PCR-RFLP (restriction fragment length polymorphism) method. The allele frequencies of DMB*0101 allele were increased in SSc with diffuse scleroderma (70.0% vs 49.4%, p < 0.05, pc = not significant (NS)) and in SSc with antitopoisomerase I antibody (a-Scl-70), (68.2%, p < 0.05, pc = NS). The phenotype frequencies of DMB*0101 in these subgroups of SSc were increased significantly (95.0%, p = 0.014, pc < 0.05; 95.5%, p = 0.0088, pc < 0.05, respectively). In contrast, DMB*0102 and DMB*0103 alleles tended to decrease in diffuse scleroderma and SSc with a-Scl-70, but the decreases were not significant. Association analysis among DMA, DMB, and DRB1*1502 in Japanese SSc with diffuse scleroderma and SSc with a-Scl-70 indicated that the increase in DMA*0101 was not primary, but reflected an increase in HLA DRB1*1502.

Adult↗