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Biomedical subjects

T Shikata

Publications and source records attributed to T Shikata.

At least 127 records · Page 7Linked to original sources
PubMed1986

Transmission of non-A, non-B hepatitis agent to chimpanzees from patients of epidemic hepatitis.

Two chimpanzees were inoculated intravenously with acute-phase sera obtained from two patients with epidemic hepatitis. They developed histopathologically confirmed hepatitis. Electron microscopic examination of the liver showed peculiar cytoplasmic tubular structures in the hepatocytes. These ultrastructural findings were similar to those described for the livers of chimpanzees inoculated with the F strain of non-A, non-B hepatitis agent derived from a posttransfusion hepatitis case. The chimpanzee that had recovered from hepatitis caused by the F strain of non-A, non-B hepatitis agent was re-challenged with the serum from one of the patients. The chimpanzee developed neither clinical signs nor histological changes of hepatitis. These results suggested that non-A, non-B hepatitis agent was involved not only in post-transfusion hepatitis but also in epidemic hepatitis.

Animals↗
PubMed1986

Clonal origin of human hepatoma determined by integration of hepatitis B virus DNA.

The hepatitis B virus genome is integrated in cellular DNA of human hepatocellular carcinoma from hepatitis B surface antigen-positive patients. Using this phenomenon, we determined the clonal origin of hepatocellular carcinoma from the integration mode of hepatitis B virus DNA. The molecular size and the number of restriction fragments of integrated hepatitis B virus DNA in several parts of tumors in the same liver and in metastatic tumors were compared by Southern blot analysis. Of 14 cases of hepatoma, 13 cases were monoclonal; in one case, a different clone of hepatoma was found in one part of the tumor. In three of 13 cases of monoclonal hepatoma, metastatic tumors in lymph nodes and the lung were also examined and found to be the same clone as the liver tumors. These results indicate that hepatocellular carcinomas were usually generated from a single tumor cell even though tumor cells spread in the liver and invaded other organs for a long time. Development of different clones of tumor was apparently unusual but was observed in one case of hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1985

Localization of hepatitis B surface and core antigens in human hepatocellular carcinoma by immunoperoxidase methods. Replication of complete virions of carcinoma cells.

The localization of hepatitis B surface antigen (HBsAg) and core antigen (HBcAg) was investigated by an indirect immunoperoxidase method in formalin-fixed, paraffin-embedded liver specimens obtained from 95 Japanese patients with hepatocellular carcinomas. Routine and immune electron microscopic examinations were done in one case. The correlation between expression of hepatitis B virus antigens in the tissue and serum hepatitis B e antigen (HBeAg)/antibody to HBeAg (anti-HBe) status was examined. Hepatitis B surface antigen was detected in the cytoplasm of noncarcinomatous hepatocytes in 28 (29.5%) cases and of carcinoma cells in 11 (11.6%) cases. Hepatitis B core antigen was stained in noncarcinomatous hepatocytes in 13 (13.7%) cases and in carcinoma cells in 4 (4.2%) cases. Hepatitis B core antigen was present mainly in the nuclei, and all HBcAg-positive cases were positive for HBsAg. The routine electron microscopic examination revealed many round particles, 25 to 30 nm in diameter both in the nuclei and in the cytoplasm, and larger particles, 40 to 45 nm in diameter in the cytoplasm of carcinoma cells. Both types of particles had reaction products of HBcAg by immunoelectron microscopic study. Therefore, it was confirmed that the former were cores and the latter were Dane particles. There was a tendency that HBeAg-seropositive cases showed localization of HBcAg in the noncarcinomatous tissue. Among four cases with positive HBcAg in carcinoma cells, two were positive for HBeAg, one was positive for anti-HBe, and the other was negative both for HBeAg and anti-HBe in the sera. The data suggested occasional production of complete hepatitis B viruses of carcinoma cells in anti-HBe-positive as well as in HBeAg-positive hepatocellular carcinomas.

Adult↗
PubMed1985

Karyometric analysis of liver cell dysplasia and hepatocellular carcinoma. Evidence against precancerous nature of liver cell dysplasia.

Karyometric analysis was performed with respect to anisonucleosis, nuclear deformity and DNA content in cases of liver cell dysplasia (LCD) and hepatocellular carcinoma (HCC). Presence or absence of iron deposition in foci of LCD and HCC was also evaluated in siderotic livers. All LCDs showed marked anisonucleosis and marked increases in DNA content but slight increases in nuclear deformity. A tendency was noted in which the nuclear deformity was increased as the nuclei became larger. In contrast, HCCs showed wide ranges of anisonucleosis, nuclear deformity and DNA content. Hepatocellular carcinomas having marked anisonucleosis similar to that of LCD showed markedly increased nuclear deformity. However, unlike LCD, this increase was independent of their nuclear size. In the siderotic livers iron deposition was noted in the foci of LCD but not in the foci of HCC. These findings do not support the notion of LCD being precancerous.

Carcinoma, Hepatocellular↗
PubMed1985

Reduced collagen biosynthesis in oral mucosa of beige (Chediak-Higashi) mice.

Oral mucosa of beige (Chediak-Higashi) mice had decreased levels of collagen synthesis and prolyl hydroxylase activity compared with normal animals. No significant difference was observed in non-collagen protein synthesis between the two groups. These results suggest that decreased collagen biosynthesis in oral tissues may be partially involved in the increased incidence of periodontal disease in the Chediak-Higashi syndrome.

Animals↗
PubMed1985

AN6520 Ag: an antigen purified from liver with non-A, non-B hepatitis.

An extract prepared from the liver of patient with chronic non-A, non-B (NANB) hepatitis was found to produce a precipitin line in immunodiffusion with a serum from a multiply transfused patient and those from patients convalescent from NANB hepatitis. The antigen was purified by gel filtration and density gradient centrifugation. The antigen had a buoyant density of 1.16-1.20 g/cm3 in cesium chloride, a sedimentation coefficient (S20,w) of 51.5, and a molecular weight of larger than 1.5 X 10(6) daltons. Electron microscopic examination revealed particles 29-34 nm in diameter (average 31.5 nm), which could be agglutinated by the specific antiserum. We developed a reverse passive hemagglutination (R-PHA) and a passive hemagglutination (PHA) technique for detection of the new antigen and antibody, respectively, and applied these to human sera. Antibody to the antigen was detected in 19/28 (67.9%) convalescent sera of NANB hepatitis. This prevalence was significantly higher than those found in convalescent sera of type A hepatitis patients (2/17 = 11.8%), type B hepatitis patients (2/15 = 13.3%), and normal blood donors (9/129 = 7.0%) (p less than 0.01); and the prevalence in hepatitis A and B patients did not differ significantly from that of normal donors. Furthermore, most (66.7%) of the cases of NANB hepatitis endemic in Shimizu City, Japan, showed clear seroconversion with respect to this antibody. These results suggest that the new antigen/antibody system is associated with NANB hepatitis.

Adult↗
PubMed1985

Localization of hepatitis B surface antigen in the human parotid gland.

Localization of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in the human parotid gland and liver was studied by an immunohistochemical method in four cases with seropositive HBsAg. Neither HBsAg nor HBcAg could be detected in the parenchymal cells of the parotid gland in any of the cases. However, one of four cases, which had the highest titer of serum HBsAg, showed HBsAg immunoreactivity in the vascular wall and luminal fluid of the parotid gland. In liver, HBsAg was detected in three and HBcAg in two of the four cases, respectively. HBsAg was localized in the cytoplasm of hepatocytes, while HBcAg was localized mainly in their nuclei. The detection of HBsAg in the parotid gland and liver was correlated with the serum titer of the antigen. The results indicate that the HB virus does not have an affinity for or a replicate in the parotid gland. Also, it is suggested that the HBsAg found in saliva is derived from HBsAg circulating through the oral mucosa by capillary leakage and not from secretion into the mouth by the salivary gland.

Adolescent↗
PubMed1985

Production of antibody associated with non-A, non-B hepatitis in a chimpanzee lymphoblastoid cell line established by in vitro transformation with Epstein-Barr virus.

A continuous cell line of chimpanzee lymphocytes producing an antibody specifically associated with non-A, non-B hepatitis (NANB) was established. Peripheral blood lymphocytes of a chimpanzee convalescent from experimental infection with NANB hepatitis were transformed in vitro by Epstein-Barr virus infection into lymphoblastoid cell lines. Supernatants of the cell cultures were screened by immunofluorescence for antibody activity against the liver tissue of a chimpanzee with NANB hepatitis. Nineteen of the 1402 cultures were found to be positive for the activity. Ten of these 19 gave cytoplasmic reactions and the remaining 9 gave nuclear reactions in hepatocytes. One culture (48-1) stably producing the antibody was further characterized. The antibody produced in 48-1 was IgM and gave granular cytoplasmic reactions in hepatocytes. Cloning of 48-1 was performed by the soft agar method and cloned cell lines stably producing the antibody were obtained. The 48-1 antibody reacted with liver biopsy specimens from 12 chimpanzees obtained during the acute or chronic phase of hepatitis caused by five different NANB strains, but not with biopsy specimens from chimpanzees with hepatitis A or B or from normal chimpanzees. In addition, examinations of serial liver biopsy specimens obtained from 2 chimpanzees experimentally infected with NANB hepatitis demonstrated that the antibody reacted with the biopsies obtained during the preacute, acute, and chronic hepatitis, but not with those obtained before inoculation, early incubation period, or during convalescence. The present results indicate the specific association of the antibody with NANB hepatitis. Immunoelectron microscopy revealed that the antibody reacted with the microtubular aggregates identical to those previously described in a patient and chimpanzees with NANB hepatitis.

Animals↗
PubMed1985

HBV-associated ultrastructures in the chimpanzees' livers with experimental hepatitis B.

An electron-microscopic study was carried out using chimpanzees' livers infected with experimental hepatitis B for the elucidation of intracellular development of HBV-associated ultrastructures and extracellular release of HBV. Core particles were first detected in the nucleus of liver cells at around the time of the first seropositiveness for HBsAg, and then in the cytoplasm. Subsequently, their budding into endoplasmic reticular cisterna was seen together with other core particles in the surrounding cytoplasm. Dane-like particles were seen in the cisterna, and also extracellularly nearby a liver cell with a marked proliferation of microvilli at the onset of liver cell injury. Thereafter, core-like particles were seen within electrondense amorphous material at the site of the contact between liver cell and lymphocyte. The above sequence of features suggested us the assembly of core particles and surface envelope at the cisternal membrane of endoplasmic reticulum, and a reversed pinocytosis whereby Dane or HBV particles were released extracellularly. The filamentous structures within endoplasmic reticular cisternae, which were thought to be HBsAg, were never detected.

Animals↗
PubMed1985

Ultrastructural changes of the bile secretory apparatus and bile ductule in experimental hepatitis B with neither apparent biochemical nor light-microscopic cholestasis.

An ultrastructural study on the hepatic bile secretory apparatus and bile ductules was carried out using liver biopsy specimens of six chimpanzees with experimental hepatitis B. Although biochemical cholestasis was very mild or lacking and light-microscopic evidence of cholestasis was not evident, various ultrastructural changes which had been described in association with cholestasis were detected. The significance of these ultrastructural changes in relevance to cholestasis was difficult to determine, nevertheless electron-microscopic examination could possibly be the most sensitive means for the diagnosis of cholestasis. These ultrastructural changes appeared to be indifferent to the necrotizing process of liver cells in experimental hepatitis B.

Animals↗
PubMed1985

Ultrastructural studies on liver cell necrosis and lymphocytes in experimental hepatitis B.

Ultrastructural studies on liver cell necrosis and the interaction of lymphocyte and liver cell were carried out in experimental hepatitis B in chimpanzees. Two types of liver cell necrosis were identified. One was a lytic necrosis, and the other was a coagulation necrosis. Both types of liver cell necrosis were closely associated with the apposition of lymphocytes. The interaction (or close contact) of lymphocyte and non-necrotic liver cell infected with HBV was also detected. There were two distinct patterns of the contact. One was the direct contact, and the other was the contact with the intervention of electron-dense fuzzy material containing 20 to 22 mu spherical particles and 51 to 55 mu double-layered spherical particles. The ultrastructural characteristics of lymphocytes in each pattern of the contact were different. The results suggested that the pathogenesis of liver cell necrosis in hepatitis B was closely associated with the action of lymphocytes, and two modes of lymphocytic reaction were conceivable.

Animals↗
PubMed1985

Blood pressure tracking in Japanese adolescents. Five-year follow-up in Hisayama, Japan.

Blood pressures (BPs) were measured with standardized sphygmomanometers in 434 Japanese boys and girls living in the town of Hisayama. Simultaneously, data on pulse rate, weight and height were obtained. Out of the original 434 subjects, data were obtained repeatedly for 5 years in 280 subjects. BP levels were significantly correlated with weight in those aged 14-15 and also 19-20 years, but correlation coefficients were small. During the 5-year period, the mean systolic and diastolic blood pressure (SBP & DBP) increased significantly in both sexes, but the increments were greater in boys. Both SBP and DBP at 14-15 years of age were significantly correlated with data taken 5 years later for both sexes, and subjects with a higher initial BP (more than 90th percentile of the distribution) tended to have a higher BP after 5 years. SBPs after 5 years were independently correlated with initial SBP levels and changes in QI (D-QI) in both sexes. On the other hand, DBPs after 5 years were independently correlated with initial DBP levels and height for boys, and initial DBP levels and D-QI for girls.

Adolescent↗
PubMed1984

Immunohistochemical localization of nerve growth factor and epidermal growth factor in guinea pig prostate gland.

Prostate glands of adult guinea pigs were stained for nerve growth factor (NGF) and epidermal growth factor (EGF) by immunohistochemical methods. Both NGF and EGF were localized diffusely in the cytoplasm of the glandular epithelial cells, and also in their secretory products. These findings suggest that NGF and EGF are synthesized, stored, and secreted by the glandular epithelial cells of the prostate.

Animals↗
PubMed1984

Natural history of borderline hypertension in the Hisayama community, Japan--I. The relative prognostic importance of transient variability in blood pressure.

Long-term prognosis of borderline hypertensives was studied in a prospective population survey carried on since 1961 in the town of Hisayama, Japan. Five consecutive BP recordings on 1621 subjects aged 40 and over were obtained at entry, and the variability in BP between the first and fifth readings was taken into account when classifying the subject into categorical groups. Even with an estimated variability in BP in several measurements on one occasion, a large fluctuation in BP was observed in both the borderline hypertensives and the normotensives. Borderline hypertensives with a transient elevation in BP more frequently died from cardiovascular disease than did those without BP elevation, as estimated by the long-term cumulative mortality. However, there was no difference in the frequency of hypertension-related organ damage between these two groups at entry.

Adult↗
PubMed1984

Susceptibility of hepatitis B virus to disinfectants or heat.

Using direct chimpanzee inoculation as an assay method, we tested the abilities of the following chemical or physical treatments to inactivate hepatitis B virus in human plasma: 1% aqueous glutaraldehyde at 24 degrees C for 5 min, 0.1% aqueous glutaraldehyde at 24 degrees C for 5 min, 80% ethyl alcohol at 11 degrees C for 2 min, and heat at 98 degrees C for 2 min. All treatments were shown to be effective, indicating that the resistance level of the hepatitis B virus is not extreme.

Aldehydes↗