Biomedical subjects

H Tsubouchi

Publications and source records attributed to H Tsubouchi.

At least 73 records · Page 4Linked to original sources

PubMed1997

Persistent clonal proliferation of human T-lymphotropic virus type I-infected cells in vivo.

Clonal proliferation of human T-lymphotropic virus type I (HTLV-I)-infected cells has been detected by Southern blot analysis and inverse PCR in patients with adult T-cell leukemia, patients with HTLV-I-associated diseases, and even in asymptomatic carriers. Combining inverse PCR with long PCR, we amplified the genomic DNA regions flanking the integration sites of the HTLV-I provirus to detect clones of infected cells. Inverse long PCR revealed that increased virus load was associated with an increase of both the number of cells in each clone and the number of clones. Clonal proliferations were found in both CD4- and CD8-positive cells in a carrier and a patient with HTLV-I-associated neuropathy/tropical spastic paraparesis. These HTLV-I-infected clones persisted over several years in the same carriers, and, moreover, most of the persistent clones were CD4 positive in a HTLV-I carrier. These findings indicate that HTLV-I infection plays an important role in the clonal expansion of lymphocytes and the prolonged survival of CD4-positive cells in vivo. Surviving T-lymphocytes may be susceptible to genetic changes, leading to the onset of leukemia.

Adult↗

PubMed1997

Heterosexual transmission of hepatitis C virus among married couples in southwestern Japan.

The heterosexual transmission of hepatitis C virus (HCV) remains controversial, and data from general populations are scanty. In this cross-sectional study, we assessed the seroprevalence of antibodies to hepatitis C virus (anti-HCV) and the presence and genotype of HCV-RNA among 109 married couples within an endemic, community-based Japanese population. Overall, 25% of the husbands and 32% of the wives had anti-HCV. Spouses with anti-HCV-positive partners were around 2 times more likely to have anti-HCV than spouses with anti-HCV-negative partners (p = 0.01). Of 6 couples in which both spouses had HCV-RNA, however, 3 presented discordant HCV genotypes (type 1b vs. 2b). The couples' anti-HCV concordance status was not significantly influenced by the presence or absence of HCV-RNA among anti-HCV-positive partners (odds ratio [OR]: 0.8 for wives, 0.6 for husbands), nor by the length of marriage, the number of pregnancies or the use of contraceptives. No significant associations with anti-HCV were observed for serum markers of sexually transmitted agents, including human T-lymphotropic virus (OR = 1.1, 95% confidence interval [CI] 0.5-2.3), Treponema pallidum (OR = 0.7; CI 0.1-6.1) and hepatitis B virus (OR = 1.6; CI 0.9-3.0). Our results suggest that the clustering of HCV infection among specific couples within this endemic population may not be attributable to heterosexual transmission. Follow-up studies are necessary to determine the risk of heterosexual transmission of HCV in endemic areas.

Adult↗

PubMed1997

Increased expression of interleukin-2 receptor alpha on peripheral blood mononuclear cells in HTLV-I tax/rex mRNA-positive asymptomatic carriers.

Using the double-nested reverse transcription-polymerase chain reaction, we assayed human T-cell leukemia virus type I (HTLV-I) tax/rex-encoded mRNA in the peripheral blood mononuclear cells (PBMCs) of asymptomatic carriers as an index of the expression of HTLV-I in vivo in relation to the proviral DNA level. HTLV-I tax/rex mRNA was detected in only 1 (3.3%) of 30 samples with medium or lower proviral DNA levels, but it was detected in 11 (39.3%) of 28 samples with high HTLV-I proviral DNA levels, estimated as equal to or more than the proviral DNA of 10 ng of HUT102 (i.e., HUT102 cells were used as positive controls). The mean number of interleukin-2 receptor alpha (IL-2R alpha)-positive cells as a percentage of the total number of PBMCs was higher (13.2%) in the tax/rex mRNA-positive carriers with high proviral DNA levels than in the carriers who were mRNA negative (8.4%) (p = 0.004, Wilcoxon test). These results suggest that virus activation as indicated by the presence of tax/rex mRNA in asymptomatic carriers with high proviral DNA levels is associated with an elevation of the IL-2R alpha-positive cells in vivo.

Carrier State↗

PubMed1997

Hepatocellular carcinoma with sarcomatous change arising in primary biliary cirrhosis.

We report an autopsy case of hepatocellular carcinoma (HCC) with sarcomatous change arising in the context of primary biliary cirrhosis (PBC) in a 79-year-old man. Primary biliary cirrhosis was diagnosed (stage I according to Scheuer's classification) by findings on blood biochemical analysis, laparoscopy, and liver biopsy at age 69 years. Five years later, (at age 74 years), a mass lesion was detected in the S6 region of the liver by abdominal ultrasonography, and target biopsy revealed well differentiated HCC. Blood biochemistry, ultrasonography, and computed tomography findings showed that the PBC had progressed to stage IV (cirrhotic stage). Percutaneous ethanol injection therapy (PEIT) was administered to the HCC several times over a 5-year period; however, the patient died of liver failure in February, 1994 (at age 79 years). Viral markers for hepatitis B and C were negative during the course, and hepatitis C virus RNA was not detected by polymerase chain reaction. Autopsy findings showed liver cirrhosis and diffuse involvement of spindle-shaped sarcomatoid cells in the liver, particularly in the S6 region, associated with several nodules of trabecular HCC cells. A zone of transition between the sarcomatoid cells and the trabecular hepatocellular carcinoma cells was observed. The sarcomatoid cells were diffusely disseminated in the peritoneal cavity and had metastasized to multiple organs. Immunohistochemically, the cells were positive for fibrinogen, as were the coexisting trabecular hepatocellular carcinoma cells. The HCC had been treated several times with PEIT. Of interest, PEIT may be an important factor in this type of tumor progression.

Aged↗

PubMed1997

Response to interferon-alpha 2a in patients with e antigen-negative chronic hepatitis B.

Sixty-eight consecutive patients with chronic hepatitis B received 702 million units of recombinant interferon-alpha 2a. Of the 24 patients negative for hepatitis B e antigen (HBeAg) in serum, the normalization of serum transaminase occurred in 14 (58%) at the completion of interferon therapy and in 13 (54%) at 12 months thereafter; it was normalized in 17 (39%) and 13 (30%), respectively, of the 44 HBeAg-positive patients. Of the HBeAg-negative patients, hepatitis B virus DNA was cleared from serum in six (25%) at the completion and in one (4%) at 12 months thereafter, in contrast to only one (2%, p < 0.05) and none of the HBeAg-positive patients, respectively. The 1896th nucleotide of G (G1896) for codon 28 for tryptophan or A (A1896) for the stop codon 28 in the precore region was determined by restriction fragment length polymorphism. The ten HBeAg-negative patients with A1896 only in the precore region had lower pretreatment levels of viral markers, which decreased more rapidly and extensively after interferon than in the 14 HBeAg-negative patients with a mixture of G1896 and A1896 or in the 44 HBeAg-positive patients. These results indicate that patients with HBeAg-negative chronic hepatitis B may respond better to interferon than HBeAg-positive patients, and that the precore mutant with the stop codon 28 may be sensitive to interferon.

Adult↗

PubMed1997

Prevalence of genotypes of Orientia tsutsugamushi in patients with scrub typhus in Miyazaki Prefecture.

The genotypes of Orientia tsutsugamushi in patients with scrub typhus in Miyazaki Prefecture were examined by polymerase chain reaction (PCR) and the restriction fragment length polymorphism method. Specific patterns for genotypes Irie, Hirano, Tazume and Yoshimura were detected in 26, 6, 5 and 2 of 39 DNA samples obtained from peripheral blood mononuclear cells, respectively. DNA sequences of the PCR products from the Tazume strain were genetically very close to the Hirano strain and the Yoshimura strain was also very close to the Karp strain. Furthermore, the DNA sequences from the Irie and Tazume strains were completely homologous to the reported sequences of the Kawasaki and Kuroki strains, respectively.

Base Sequence↗

PubMed1997

Relationship between cellular ATP content and cellular functions of primary cultured rat hepatocytes in hypoxia.

The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo, perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 x 10(4) and 5 x 10(4) cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.

Adenine Nucleotides↗

PubMed1997

Progressive retinitis-encephalitis due to ganciclovir-resistant cytomegalovirus associated with aplastic anemia.

A 29-year-old woman with aplastic anemia who complained of visual disturbances and pain in the right eyeball was diagnosed as having cytomegalovirus (CMV) retinitis based upon the characteristic retinal changes and isolation of CMV. She received treatment with ganciclovir (GCV), and the retinitis initially responded for several months. However, the patient was found to have CMV lesions in the left eye followed by neurological symptoms. The CMV isolated just before her death was approximately 20 times more resistant to GCV than that isolated previously, suggesting that the GCV-resistant CMV had developed during the long-term treatment with GCV.

Adult↗

PubMed1997

Detection of polyanion-restricted anti-histone antibodies in patients with systemic lupus erythematosus.

The nature of the antibodies responsible for lupus erythematosus (LE) cells in systemic lupus erythematosus (SLE) remains obscure. We examined whether polyanion-restricted anti-histone antibodies were present in serum of patients with SLE using Western blotting analysis. Dextran sulfate or alginate was used as a polyanion compound in place of DNA. Antibodies which recognized dextran sulfate-histone complexes were present in serum of patients with SLE (17/34, 50%). These antibodies were detected in most SLE patients positive for LE cells (17/18, 94%) but not in those negative for LE cells or in patients with other collagen diseases. Similar results were obtained using alginate-histone complexes as antigens for Western blotting analysis. The antibodies to dextran sulfate-histone or alginate-histone complexes in serum of SLE patients were completely absorbed by treatment of serum with DNA-histone complexes, while they were unaffected by treatment with DNA only. The presence of antibodies to free histones and dextran sulfate-histone complexes did not seem to be related to the titer of anti-single stranded DNA antibody and anti-double stranded DNA antibody. We demonstrated the presence of polyanion-restricted antibodies in SLE, which may be responsible for the LE factor.

Adolescent↗

PubMed1996

HCV infection and liver cancer mortality in a Japanese population with HTLV-I.

In a cohort study of human T-lymphotropic virus type I (HTLV-I) infection in Japan, 10 cases of liver cancer death occurred from 1984 through 1993. To analyze the role of hepatitis C virus (HCV), which has been associated with an increasing incidence of hepatocellular carcinoma (HCC) in Japan, a nested case-control study was performed. Five of the 10 liver cancer cases were positive for antibody to HTLV-I (anti-HTLV-I). The possible interaction between HCV and HTLV-I infections in the etiology of HCC was investigated, with each liver cancer case matched to 5 cohort controls by gender, age, serum sample date and anti-HTLV-I status. Using a matched analysis odds ratio (OR) were generated for the relationship between HCV serologic status and death liver cancer. Based on second-generation enzyme immunoassay with confirmation by recombinant immunoblot assay, 8 of 9 cases with adequate serum available (89%) and 9 of 50 (18%) controls were found to be positive for antibody to HCV (anti-HCV). Liver cancer death was highly associated with anti-HCV (matched OR = infinity; p < 0.001). Anti-HTLV-I seroprevalence was some what correlated with HCV infection. However, the high risk of liver cancer death observed for anti-HCV-positive Individuals in this population did not vary with respect to whether or not the subjects were also infected with HTLV-I.

Aged↗

PubMed1996

Effects of hepatocyte growth factor (HGF) on human glioma cells in vitro: HGF acts as a motility factor in glioma cells.

Expression of c-Met, the receptor for hepatocyte growth factor (HGF), and the biological roles of HGF were examined in cultured human glioma cells. All of the 5 glioma cell lines examined expressed c-Met protein as well as the c-met gene. Expression of the c-met gene was also confirmed in a glioblastoma tissue. Three cell lines (MGM-3, U251, KG-1-C) demonstrated chemotactic response to HGF in a dose-dependent manner. The response was not only chemotactic but also chemokinetic as judged by a checkerboard analysis. The amounts of c-Met mRNA and protein were abundant in the cell lines which showed a migratory response to HGF. Moreover, c-Met protein expression was highest in U251 with the highest migratory response to HGF. Among the cell lines, KG-1-C produced notable amounts of HGF protein as well as of c-Met, suggesting that HGF may act in an autocrine fashion in this case. HGF did not act as an apparent growth factor in the glioma cell lines examined. Furthermore, HGF stimulated the production of metalloproteinase, probably gelatinase A, in U251 cells.

Cell Division↗

PubMed1996

Liver hepatocyte growth factor does not always correlate with hepatocellular proliferation in human liver lesions: its specific receptor c-met does.

Increased levels of expression of hepatocyte growth factor (HGF) and its specific receptor c-met have been shown in the liver of several benign and malignant pathologies, both in experimental models and humans. We investigated by immunohistochemistry the presence of both HGF and c-met protoocogene product (c-met pp) in 20 hepatocellular carcinomas (HCCs), 5 focal nodular hyperplasias (FNHs), 4 cases of fulminant hepatitis (FH), and 1 case of regenerated liver. The c-met protooncogene product was expressed in all cases with marked overexpression in the HCCs and in ductular metaplasia. HGF was detected in the Ito cells of all cases and in neoplastic hepatocytes of 9 of 20 HCCs (45%). The proliferative index of each lesion was evaluated by means of the polyclonal antibody anti-cyclin A. When the level of expression of HGF and c-met protooncogene product with the percentage of cyclin A+ nuclei were compared, the closest relationship was between c-met protooncogene product and cyclin A+ nuclei were compared, the closest relationship was between c-met protooncogene product and cyclin A. In 11 of 20 HCCs (55%), there wa no correlation between HGF positivity and cyclin A. This seems to suggest that, independently of the levels of native liver HGF, c-met protooncogene product is the most active modulator of liver cell proliferation.

Biomarkers↗

PubMed1996

Role of macrophages in regeneration of liver.

In an attempt to clarify the role of macrophages and their mediators during regeneration of the liver, the difference of liver regeneration among C3H/HeN (LPS-responsive strain) and C3H/HeJ (LPS-resistant strain) mice was investigated. After a 67% partial hepatectomy, an increase in the weight of regenerating liver was significantly delayed in the C3H/HeJ mice, as compared with C3H/HeN mice. The number of hepatocytes labeled with antibody against PCNA reached maximum levels 48 hr after partial hepatectomy, but the PCNA labeling index in C3H/HeJ mice was 20% less than that for C3H/HeN mice. In addition, TNF-alpha activities in serum were enhanced shortly after partial hepatectomy in C3H/HeN strain mice, but were not increased in C3H/HeJ strain mice. Serum IL-6 levels were markedly enhanced in both C3H/HeN and C3H/HeJ mice, but a bimodial peak (14 and 48 hr after partial hepatectomy) was demonstrated in C3H/HeN mice, in contrast to a single peak (at 24 hr) in C3H/HeJ mice. Suppression of Kupffer cells by previous administration of gadolinium chloride in C3H/HeN mice reduced the increase in both serum TNF-alpha and IL-6 concentrations, reduced PCNA labeling index of hepatocytes by 20%, and disturbed the regeneration of the liver. Previous administration of antibody against TNF-alpha reduced the PCNA labeling index of hepatocytes by 20% after partial hepatectomy in C3H/HeN strain mice. These results suggest that LPS-responsive macrophages in the liver and their mediators, especially TNF-alpha, could partly play a role in liver regeneration.

Animals↗

PubMed1996

Liver cell adenoma in a young man with elevated serum PIVKA-II level.

A 21-year-old man was referred to our hospital because of a liver mass lesion detected by abdominal ultrasonography. He had received no hormonal treatment. Physical examinations revealed no abnormalities, and laboratory data, including hepatic function test results, were within normal ranges, with the exception of elevated levels of serum protein induced by vitamin K absence or antagonist (PIVKA)-II (2.2 AU/ml). Abdominal ultrasonography revealed a hyperechoic mass lesion measuring 10 x 10 cm, with hypoechoic areas located in the right posterior segment of the liver. A low-density area and a hypervascular area were detected in the right posterior segment of the liver by computed tomography and celiac angiography, respectively. As hepatocellular carcinoma could not be completely excluded, the tumor was resected. The tissue consisted of sheets of tumor cells with eosinophilic cytoplasm and round nuclei showing a thin trabecular pattern, and these histological findings indicated liver cell adenoma. After resection of the tumor, serum PIVKA-II returned to the normal level.

Adenoma, Liver Cell↗

PubMed1996

Expression of CD26/dipeptidyl peptidase IV in adult T cell leukemia/lymphoma (ATLL).

The association of CD26/dipeptidyl peptidase IV (DPPIV) and human T lymphotropic virus type I (HTLV-I) was studied by two approaches. First, we examined the expression of CD26 in peripheral blood mononuclear cells (PBMC) from the patients with adult T cell leukemia/lymphoma (ATLL), an HTLV-I-related malignancy. The expression of CD26 on the surface of PBMC was decreased in all 20 patients with ATLL compared with those from normal individuals (P < 0.01) and the expression of the CD26 gene transcript was not detectable in seven out of eight patients with ATLL. Then we compared the quantity of viral DNA in CD26-negative (CD26-) and CD26-positive (CD26+) cells obtained from 17 HTLV-I healthy carries by using a polymerase chain reaction method. The CD26-cells had a higher copy number of viral DNA than CD26+ cells. These findings indicate that HTLV-I has in vivo tropism to CD26- cells, suggesting that some phenotypes of ATLL cells reflect the in vivo cellular tropism of HTLV-I.

Adult↗

PubMed1996

Synthesis and structure-activity relationships of cephalosporins, 2-isocephems, and 2-oxaisocephems with C-3' or C-7 catechol or related aromatics.

A series of cephalosporins, 2-isocephems, and 2-oxaisocephems with C-3' catechol-containing (pyridinium-4-thio)methyl groups and 2-isocephems with C-7 catechol related aromatics have been prepared and evaluated for antimicrobial activity. It turns out that these compounds have highly potent activity against Gram-negative bacteria, especially resistant pathogens such as Pseudomonas aeruginosa. The most active compound of the series was (6S,7S)-7-[2-(2-aminothiazol-4-yl)-2-[(Z)-[(1,5-dihydroxy-4-pyr idon-2-yl) methoxy]imino]acetamido]-3-[[[(4-methyl-5-carboxymethyl)thiazol-2- yl] thio]methyl]-8-oxo-1-aza-4-thiabicyclo [4.2.0] oct-2-ene-2-carboxylic acid which exhibited potent in vitro activity against clinically isolated P, aeruginosa and Acinetobacter baumanii which is also resistant to many anti-infectives, and good in vivo efficacy against clinically isolated P aeruginosa.

Animals↗

PubMed1996

MHC class II restriction for T cell proliferative response to mite antigen.

BACKGROUND: We investigated the immunoreguratory role of the major histocompatibility complex in peripheral blood lymphocytes' proliferative response to mite antigen. METHOD: Peripheral blood lymphocytes of Japanese asthmatic patients were incubated with antigen obtained from Dermatophagoides pteronyssinus with a molecular weight of about 15,000, with and without 0.05 microgram/mL of monoclonal antibody against HLA class I or class II for seven days at 37 degrees C humidified in 5% CO2 and 95% air. RESULTS: High and low responders to the mite body antigen were found among the patients while there were no high responders among the healthy individuals tested. In the mite-sensitive asthmatic patients, CD4+ T cells were the population that responded to the antigen. Depletion of CD8+ T cells from the peripheral blood lymphocytes of mite-insensitive individuals caused high responsiveness to the antigen, indicative that the mite-specific CD4+ T cells controlled the high responsiveness and the antigen-specific CD8+ T cells, the low responsiveness. Anti-HLA-DR monoclonal antibody inhibited responsiveness. In contrast, anti-HLA-DQ monoclonal antibody produced high responsiveness in low responders to mite antigen. CONCLUSION: High T cell proliferative responsiveness to mite antigen was restricted by HLA-DR antigen through CD4+ T cells in high responders, whereas HLA-DQ antigen is a restriction antigen of low responsiveness through CD8+ T cells in low responders and non-atopic individuals.

Animals↗

PubMed1996

Clinical significance of CD45RO expression on peripheral blood mononuclear cells in HTLV-I-infected individuals.

The phenotype of peripheral blood mononuclear cells (PBMC) was examined in 13 healthy volunteers, 26 HTLV-I carriers, and 58 ATL patients (22 smouldering, five chronic, 24 acute, and seven lymphoma type). The percentage of CD4+, CD25+, CD28+ and CD45RO+ cells in the PBMC of the chronic and acute type patients was significantly higher than that of the volunteers, whereas the percentage of CD8+ and CD45RA+ cells in these patients was significantly low. The histogram for CD45RO fluorescence intensity (FI) revealed two patterns: pattern A consisted of CD45RO+ cells with high FI (CD45ROhigh) and intermediate FI (CD45ROint). Pattern B consisted exclusively of CD45ROhigh. Pattern A was evident in all volunteers. The percentage of subjects showing pattern B was increased in an order that reflected disease progression. In the patients with pattern A, the CD45ROint cells were CD4+ and CD8-, and the FI of CD2, CD3, and Fas within the CD45ROint cells appeared to be lower than that within the CD45ROhigh cells. The acute type patients with pattern A had a significantly longer survival curve than that of these patients with pattern B. These results suggest that the presence of CD45ROint cells may be related to protection against disease progression in HTLV-I-infected individuals.

Acute Disease↗