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H Ikematsu

Publications and source records attributed to H Ikematsu.

At least 19 recordsLinked to original sources
PubMed1995

Intrafamilial transmission of hepatitis-C virus among the population of an endemic area of Japan.

OBJECTIVES: To assess the role of intrafamilial transmission of hepatitis C virus (HCV) among general populations. DESIGN AND SETTING: Cross-sectional study in an HCV-endemic area of Japan. PARTICIPANTS: A total of 1122 residents (mean age, 41.7 years; range, 0 to 80 years), including 359 mother-child pairs and 234 pairs of spouses. MAIN OUTCOME MEASURES: Antibody to HCV (anti-HCV) was examined using second-generation anti-HCV testing by passive hemagglutination assay. Hepatitis C virus RNA was detected by polymerase chain reaction with primers deduced from the 5'-noncoding region and HCV genotypes by reaction with type-specific primers deduced from the HCV core gene. RESULTS: Prevalence of anti-HCV was 14.1% (158/1122), and HCV RNA was detected in 82.9% of those who tested positive for anti-HCV. Prevalence of anti-HCV increased with advancing age, but no anti-HCV was found among 312 persons younger than 20 years. Of the 53 children with anti-HCV-positive mothers, three were positive for anti-HCV, all were older than 20 years, and all had a history of surgical treatment. Hepatitis C virus RNA was found in one mother-child pair but with different HCV genotypes. Both spouses were positive for anti-HCV in 17 of 234 pairs. Of the 11 pairs of spouses in whom the HCV genotypes of both were determined, five had different HCV genotypes. CONCLUSIONS: While HCV is highly endemic in this area, neither vertical nor horizontal transmission between spouses seems to play an important role in its spread. The incidence of intrafamilial transmission of HCV seems to be low.

Adolescent↗
PubMed1995

Serum levels of soluble interleukin-2 receptors and effects of interferon-alpha for patients with chronic hepatitis C virus.

To characterize the role of serum soluble interleukin-2 receptor (sIL-2R) in hepatitis C virus (HCV) infection, the level of sIL-2R was measured by ELISA in 117 subjects with chronic HCV infection and in 23 healthy controls. HCV RNA was detected by polymerase chain reaction in all subjects with HCV infection. Forty-seven patients with chronic hepatitis and 10 with liver cirrhosis were treated for six months with natural interferon-alpha. The sIL-2R levels of 40 asymptomatic HCV carriers (632 +/- 340 units/ml), 47 patients with chronic hepatitis (547 +/- 204 units/ml), 10 with cirrhosis (679 +/- 239 units/ml, and 20 with hepatocellular carcinoma (1145 +/- 487 units/ml) were significantly higher than those of healthy controls (380 +/- 191 units/ml) (P < 0.05, respectively). The levels of sIL-2R increased, as did the histological activity index scores (r = 0.348, P < 0.01). The level of sIL-2R rose after the initial administration of interferon in all 57 patients. In patients whom HCV RNA was eliminated from the sera within a six-month follow-up after cessation of treatment, the level of sIL-2R reverted to basal values, but in patients in whom HCV RNA was not eliminated the value was significantly higher than that before treatment. These results suggest that monitoring serum sIL-2R in patients with chronic HCV infection treated with interferon may provide information concerning the possibility of the elimination of HCV RNA.

Carcinoma, Hepatocellular↗
PubMed1995

Relationship of genotype to level of hepatitis C viraemia determined by competitive polymerase chain reaction.

To compare the levels of hepatitis C virus (HCV) viraemia in carriers of the same genotype in various stages of chronic HCV infection, we quantified the amount of HCV RNA by competitive polymerase chain reaction and determined HCV genotype using type-specific primers. The study population included 255 patients with chronic HCV infection (asymptomatic 33, chronic hepatitis 141, liver cirrhosis 50, hepatocellular carcinoma 31). Of these 255, the prevalence of HCV RNA genotype II was 67.8%, genotype III, 17.3% and genotype IV, 14.9%; no genotype I was found. The level of HCV RNA (logarithmic transformed copy numbers per 50 microliters of serum) was significantly higher in subjects of genotype II than in those of genotypes III or IV (mean titre 5.8 +/- 1.0 vs. 5.1 +/- 1.2 and 4.8 +/- 1.1, P < 0.05, respectively). There was no significant difference in the level of HCV RNA between genotypes III and IV. Of 173 patients of genotype II, there were no significant differences between the level of HCV RNA and the stage of liver disease or in the level of HCV RNA by age. Of the 129 with genotype II with a history of blood transfusion, there was no significant difference between the level of HCV RNA of patients with and without a history of transfusion or between that of patients with a history of blood transfusion and the time elapsed since blood transfusion. The level of HCV viraemia depended on the genotype of HCV RNA and did not correlate to age or to the stage of liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Higher expression levels of alternatively spliced pX mRNA in human T lymphotropic virus type I asymptomatic carriers positive for antibodies to p40tax protein.

cDNA of human T lymphotropic virus type I (HTLV-I) pX gene mRNA expressed in peripheral blood lymphocytes of asymptomatic carriers was sequenced. One cDNA clone contained a novel splicing acceptor site, indicating an unidentified form of pX mRNA: pX delta 17 delta 37. All 21 asymptomatic carriers expressed some level of alternatively spliced pX mRNA (pX, pX delta 17, p21rex, orfII, or pX delta 17 delta 37). pX and pX delta 17 were the dominant mRNA species among the five pX mRNAs. All pX mRNAs but orfII correlated significantly with amounts of provirus DNA (P < .05). Levels of provirus DNA and pX mRNAs were significantly higher in anti-p40tax-positive carriers than in negative ones. These observations suggest that the pX mRNAs are expressed ubiquitously, with a complex pattern of splicing, and that the presence of anti-p40tax may serve as a marker for a higher virus load and viral replication levels in asymptomatic HTLV-I carriers.

Aged↗
PubMed1995

[Evaluation of three kinds of assays for the presence of antibody to hepatitis C virus (anti-HCV) and the association of them with HCV RNA].

In order to evaluate the feasibility for the detection of antibody to hepatitis C (anti-HCV), the first generation assay (c100-3 Ab) and two second generation assays (2nd EIA and 2nd PHA) were used to test 477 individuals who visited the medical hospital or clinics in Iki Island, Nagasaki Prefecture. HCV RNA, antibody titer by 2nd PHA and four kinds of antibody to epitope of HCV by RIBA II were also surveyed to determine their association with these three assays. Prevalence of anti-HCV was 26.6% by c100-3, 38.8% by 2nd PHA and 39.6% by 2nd EIA, indications that the 2nd generation assays are much more sensitive than c100-3. Prevalence of HCV RNA was 82.1% among 190, anti-HCV positive individuals; 100% among 52 individuals with liver disease, but only 75.4% in those without liver disease. HCV antibody titer, over 2(11) was higher among those who were positive for HCV RNA than those negative for HCV RNA. Four antibodies by RIBA II were all positive and reacted strongly when they were positive for HCV RNA, but only antibody to core antigen was observed among those negative for HCV RNA, suggesting that only antibody to core antigen remains in those with past HCV infection.

Adolescent↗
PubMed1995

A preliminary study of retreatment of chronic hepatitis C with interferon.

Nine patients with chronic hepatitis C virus (HCV) infection and no complete response to the first treatment with natural interferon (IFN)-alpha, were prescribed a second treatment with IFN. Five patients (Group A) with unsustained levels serum alanine aminotransferase (ALT) after the first treatment were administrated the same species of IFN but in a higher dose. The remaining four patients (Group B), with no normalization of ALT throughout the observation period of the first treatment, were administrated IFN-beta. HCV RNA was eliminated in three patients of group A and in two of group B patients during 6 months follow up and ALT reverted to normal levels. These results suggest that retreatment with a higher dose of the same species of IFN-alpha can be effective in case of a relapse and that IFN-beta can be effective for those not responding to IFN-alpha.

Adult↗
PubMed1994

Surface phenotype and Ig heavy-chain gene usage in chronic B-cell leukemias: expression of myelomonocytic surface markers in CD5- chronic B-cell leukemia.

We investigated the surface expression of leukocyte differentiation antigens and the Ig heavy-chain variable region (VH) gene family use in leukemic cells from 26 Japanese patients with chronic B-cell leukemias with special reference to CD5 antigen expression. CD5 was expressed on leukemic cells in 21 of 26 cases (CD5+) but not in 5 cases (CD5-). Myelomonocytic marker, CD13 antigen was expressed on the leukemic cells in all 5 CD5- cases but in none of CD5+ cases. Leukemic cells in CD5- cases also expressed CD11b antigen more frequently than those in CD5+ cases (80% v 11%; P < .01). Another myeloid marker, CD33, was expressed neither on CD5+ nor CD5- leukemic cells. CD22, a restricted B-cell marker, was expressed more frequently on CD5- leukemic cells than on CD5+ leukemic cells (80% v 33%; P < .05). Another restricted B-cell activation marker, CD23, was expressed at similar frequency in both the CD5+ and CD5- groups (67% v 60%). Although CD45RA was expressed on the majority of leukemic B cells, the CD45RA expression level was significantly higher among CD5- cases than CD5+ cases (P < .01). In the analysis of VH gene expressed in chronic B-cell leukemias by polymerase chain reaction amplification, CD5+ cases preferentially used VH4 family members (48%; 10 of 21). CD5- cases, on the other hand, mainly used VH3 family (80%; 4 of 5). Thus, from our present observation of an albeit limited patient population, we have found an association between VH gene family use and CD5 antigen expression in chronic B-cell leukemias. We have also shown the differential expression of myelomonocytic markers in the CD5+ and CD5- chronic B-cell leukemias. These result are in agreement with previous suggestions that CD5 positivity is the hallmark for distinct clinical entity commonly referred to in the literature as chronic lymphocytic leukemia.

Adult↗
PubMed1994

Seroepidemiology of hepatitis C virus infection in hemodialysis patients and the general population in Fukuoka and Okinawa, Japan.

In 1992, a seroepidemiologic study was carried out among hemodialysis patients and the general population in Fukuoka and Okinawa, Japan to determine the presence of hepatitis C virus (HCV) infection and HCV viremia. The markers used were antibody to HCV, determined by second-generation assay (anti-HCV), and HCV RNA, determined by the polymerase chain reaction. The prevalence of anti-HCV in Fukuoka was 3.3%, 73 per 2237 persons, significantly (P < 0.001) higher than the 0.4%, 5 per 1295, in Okinawa. The prevalence of anti-HCV in hemodialysis patients in Fukuoka was 51.9% (161 of 310 patients), significantly (P < 0.001) higher than the 9.1% (13 of 143 patients) in Okinawa. The ratio of HCV RNA-positive to anti-HCV-positive persons was significantly higher in hemodialysis patients (147/174, 84.5%) than in the general population (49/78, 62.8%) (P < 0.001). Elimination of HCV among hemodialysis patients appears to be difficult, as such patients have lower immune responses than the general population. In Fukuoka, but not in Okinawa, blood used for transfusion was supplied by paid donors at commercial blood banks from 1953 to 1969. This may explain why HCV infection is endemic in Fukuoka and not in Okinawa. Differences between the prevalence of anti-HCV in the hemodialysis patients in Fukuoka and Okinawa reflect differences in the prevalence in the general population in these two areas of Japan.

Adolescent↗
PubMed1994

Inverse correlation between the titre of antibody to hepatitis C virus and the degree of hepatitis C viraemia.

We titrated 277 hepatitis C virus (HCV) antibody-positive serum samples from 235 volunteer blood donors as well as from 42 outpatients of a hospital for elderly people and studied the relation of the titre of HCV antibody to the presence of HCV RNA, of antibody to C100 protein (anti-c100) and of antibody to GOR epitope (anti-GOR). Liver dysfunction was measured also. Of 177 HCV RNA-positive serum samples, 87 were tested for the degree of HCV viraemia by means of a competitive assay. Among the 277 samples, prevalences of HCV RNA, anti-c100, anti-GOR and liver dysfunction were 63.9%, 71.8%, 75.7% and 17.5%, respectively. The prevalence of HCV RNA became higher as the titre of HCV antibody increased. The titre tended to increase with age but the tendency was not statistically significant. The mean titre was higher in females (2(10.4 +/- 1.8)) than in males (2(9.4 +/- 2.2)) (P < 0.01). In the HCV RNA-positive serum samples, the HCV antibody titre was significantly higher in the anti-c100-positive samples than in the negative ones. This difference between the positive and negative samples, however, was not statistically significant for anti-GOR and liver dysfunction. Low degrees of HCV viraemia were accompanied by high titres of HCV antibody while high degrees of HCV viraemia went with low titres of HCV antibody. The study revealed that titres of HCV antibody were higher in females and the degree of HCV viraemia correlated inversely with the titre of HCV antibody.

Adolescent↗
PubMed1992

Identification and analysis of a novel human surface CD5- B lymphocyte subset producing natural antibodies.

The production of "natural" autoantibodies or antibodies, i.e., Ig that bind a variety of self- and/or exogenous Ag and arise independently of known immunization, is though to be a feature of CD5+ B lymphocytes. To determine whether other lymphocyte subsets exist that might be committed to the production of natural antibodies, human peripheral blood B cells were sorted on the basis of surface CD5 expression and differential expression of surface CD45RA (CD5+CD45RAintermediate(int), CD5-CD45RAlow(lo), and CD5-CD45RAhigh(hi)), and analyzed for the type of Ig produced after EBV infection and culture. Like their CD5+ counterparts, most CD5-CD45RAlo B lymphocytes were precursors of cells producing IgM, a major proportion of which displayed the Ag-binding features of natural antibodies. In contrast, CD5-CD45RAhi B cells comprised a high frequency of IgG-producing cell precursors, possibly including memory B lymphocytes. Six of seven IgM mAb generated from sorted CD5-CD45RAlo B cells and three of four IgM mAb from sorted CD5+ B cells were polyreactive, binding with different affinities (Kd, 10(-5) to 10(-8) M) to two or more Ag; the remaining mAb from CD5-CD45RAlo and the mAb from CD5+ B cells each bound to a single Ag (Kd, 10(-7) to 10(-8) M), beta-galactosidase and ssDNA, respectively. CD5-CD45RAlo B cells account for 4.1 +/- 1.2% (mean +/- SD in 11 healthy subjects; CD5+ B cells, 23.3 +/- 6.9%) of total B lymphocytes and display the features of quiescent cells. In a given individual, the number of CD5-CD45RAlo B cells remains constant over time. CD5-CD45RAlo and CD5+ B cells bear surface CD11b and CD14, at densities and/or frequencies apparently higher than those of CD5-CD45RAhi B lymphocytes. Despite their surface CD5- phenotype, CD45RAlo B cells express CD5+ mRNA at levels comparable with those of CD5+ B lymphocytes, whereas CD5-CD45RAhi B cells express only trace amounts of CD5 mRNA. The commitment to natural antibody production and the degree of CD5 mRNA expression suggest that the newly defined CD5-CD45RAlo B cell subset is related to CD5+ B lymphocytes, and may constitute the human homologue of the mouse Ly-1-"sister" B cell population.

Actins↗
PubMed1992

[Survival of bacteria, and release of the endotoxin from the bacterial cells in the dialysates].

Survival of bacteria and release of the endotoxin from the bacteria with and without ultraviolet irradiation in three kinds of dialysate were investigated. The results obtained are as follows: (1) No growth of S. aureus, E. coli, P. aeruginosa, Aspergillus and C. albicans in the saturated dialysates tested were observed. (2) All of the bacterial cells tested here is gradually, and naturally spontaneously inactivated in all the dialysates. (3) Among the dialysates tested, the saturated dialysate, AF-2, is the most effective for inactivating P. aeruginosa ATCC, but the effect depends upon the isolates of P. aeruginosa. (4) The inactivating effect was somewhat decreased when the saturated AF-2 solution was diluted, but the killing effect was still maintained. (5) The bacterial cells are constantly and significantly inactivated by UV irradiation, especially by the direct irradiation. The indirect irradiation, i.e., through glass, has remarkably less effective than the direct one. However, a tendency of the decrease of bacterial cells by the indirect irradiation is maintained with the killing effect of the dialysated, especially in the case of AF-2 solution. (6) No significant increase of endotoxin was observed, even when the bacterial cells were killed by UV irradiation. Therefore, it is recommended to use UV irradiation for inactivating the bacteria. From the results obtained here, it is indicated that there is no possibility of the growth of naturally contaminated bacteria in the dialysates, and is an effectiveness of the use of UV irradiation for inactivating the bacteria cells, in terms of release of the endotoxin from the dead cells.

Bacteria↗
PubMed1991

Fulminant hepatic failure during perinatal period in a pregnant woman with Wilson's disease.

Wilson's disease associated with hepatic failure is not common and the underlying mechanism triggering the event is not known at present. We treated a 28-year-old Japanese woman with Wilson's disease who developed hepatic failure associated with hemolytic crisis just after delivery. She was diagnosed as having Wilson's disease at 12 years of age, at which time she started taking D-penicillamine. She had previously delivered two children without difficulty. When she found out she was pregnant this time, she stopped taking D-penicillamine in contrast to taking it faithfully during her first two pregnancies. On the day of delivery of her full-term baby, jaundice developed accompanied with severe hemolytic crisis. Plasma exchanges and blood transfusion were performed and D-penicillamine administration was started again. She gradually recovered and apparently was following a good clinical course. However, on day 30 the second hemolytic crisis occurred and subsequent liver failure led her to death on day 50. At autopsy her liver was cirrhotic and showed massive necrosis. Prophylactic oral administration of D-penicillamine and careful observation are therefore recommended to prevent hemolytic crisis during the perinatal period.

Adult↗
PubMed1991

Decrease of hepatitis A and B virus infections in the population of Okinawa, Japan.

In 1988 1282 serum samples were collected from healthy Japanese persons living on Hateruma Island (574 samples) and Iriomote Island (708 samples) in Okinawa, Japan. Serological markers of hepatitis B virus (HBV) infection [hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc) were investigated and the findings compared with samples taken in 1980 on Hateruma Island and in 1970 and 1980 on Iriomote Island. The samples collected in 1988 on Iriomote Island were also tested for antibody to hepatitis A virus (anti-HAV) and the findings compared with the results of the 1970 and 1980 surveys. The overall prevalence of HBsAg and anti-HBc was 3.7 and 64.8% for Hateruma Island and 3.8 and 44.9% for Iriomote Island. In both areas the overall prevalence of anti-HBc was lower than in 1980, the decrease being significant for the 10-19 year age group on Hateruma Island and the age groups under 39 years on Iriomote Island. The overall prevalence of anti-HAV had fallen to 50.9%. This remarkable decrease had occurred in children and young adults. These data suggest that Virus A (HAV) and HBV infections have dramatically decreased among children in Okinawa within the past 2 decades.

Adolescent↗
PubMed1991

Complete sequence of the genes encoding the VH and VL regions of low- and high-affinity monoclonal IgM and IgA1 rheumatoid factors produced by CD5+ B cells from a rheumatoid arthritis patient.

We have characterized the VH and VL genes of three low-affinity polyreactive and two high-affinity monoreactive IgM and IgA1 rheumatoid factor (RF) mAb generated using circulating CD5+ B cells from a single rheumatoid arthritis patient. We found that four and one RF mAb utilized genes of the VHIV and VHIII families, respectively. The VHIV gene usage by these RF mAb differs from the preferential VHIII, VHI, and, to a lesser extent, VHII gene usage by the IgM with RF activity found in patients with mixed cryoglobulinemia, Waldenstrom's macroglobulinemia, and other monoclonal gammopathies. In addition, in contrast to the preponderant kappa L chain usage by the RF in these patients, a lambda L chain was utilized by all RF mAb from our rheumatoid arthritis patient. Two RF mAbs utilized V lambda I, two V lambda IV, and one V lambda III L chains. The VH genes of the two low-affinity polyreactive IgM RF mAb were in germline configuration. When compared with the deduced amino acid sequence of the putatively corresponding genomic segment, the VH gene of the high-affinity monoreactive IgM RF mAb displayed five amino acid differences, all of which are in the complementarity determining regions (CDR), possibly the result of a process of somatic point mutation and clonal selection driven by Ag. The unavailability of the corresponding genomic VH segment sequences made it impossible to infer whether the VH genes utilized by the two IgA1 RF were in a germline or somatically mutated configuration. Sequencing of the genes encoding the H chain CDR3 (D segments) revealed that all three low-affinity polyreactive RF mAb displayed a much longer D segment (36-45 bases) than their high-affinity monoreactive counterparts (15-24 bases), raising the possibility that a long D segment may be one of the factors involved in antibody polyreactivity.

Amino Acid Sequence↗
PubMed1991

CD5+ B lymphocytes.

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Amino Acid Sequence↗