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Biomedical subjects

N Ishida

Publications and source records attributed to N Ishida.

At least 505 records · Page 28Linked to original sources

Physicochemical heterogeneity of hepatitis B e antigen detected in asymptomatic carriers and carriers in a hemodialysis unit.

Physicochemical studies of hepatitis B e antigen (HBeAg) revealed a clear cut difference between e1 and e2 antigen. The e1 antigen was found to have a MW of Ca 150,000 and a pI of 6.4-7.2, whereas both the MW and pI of the e2 antigen were heterogeneous depending upon the source of serum. Sera obtained from asymptomatic carriers were characterized by low titers of HBs antigen, HBc antigen and DNA polymerase and contained e2 antigen of larger molecular weight (200,000-300,000) with a narrow distribution range and a pI of 4.8 to 5.2 (type 1). On the other hand, the sera from patients in a hemodialysis unit who were HBs antigen carriers and had high titers of HBs antigen, HBc antigen and DNA polymerase contained e2 antigen of heterogeneous distribution in MW (from 300,000 to 70,000) and pI (type 2 and 3). The e2 antigen obtained from the higher MW type 3 serum had lower isoelectric points (pI 4.5 to 5.2) as was the case with e2 antigen obtained from asymptomatic carriers whereas relatively wide range of isoelectric points (pI 5.1 to 8.2) was found with the lower molecular weight e2 antigen.

Carrier State↗

The occurrence of calicivirus in infants with acute gastroenteritis.

Calicivirus was detected in 8 (1.2%) of 647 hospitalized patients during a survey of acute gastroenteritis in infants and young children, conducted between December 1974 and September 1977. Morphologically calicivirus was approximately 30 nm in diameter with an easily recognizable staining "star of David" configuration. Its buoyant density in cesium chloride was 1.38-1.40 gm/ml. The serologic response to calicivirus by immune electron microscopy (IEM) was demonstrated only in paired sera from patients who shed the virus in their stools. The results suggest that calicivirus might be a cause of acute gastroenteritis in infants and young children.

Acute Disease↗

Non-B hepatitis in Japanese recipients of blood transfusions: clinical and serologic studies after the introduction of laboratory screening of donor blood for hepatitis B surface antigen.

Cases of hepatitis virus infection in Japanese recipients of blood transfusions were serologically and clinically analyzed after the introduction of laboratory screening of donor blood for hepatitis B surface antigen by counter immunoelectrophoresis. Non-A, non-B hepatitis occurred in 116 (10.7%) and hepatitis type B in nine (0.9%) of the 1,082 recipients. The incubation period of the post-transfusion non-A, non-B hepatitis cases varied from two to 33 weeks, but most occurred within 15 weeks. In 97 (83.6%) of the 116 cases of non-A, non-B hepatitis studied, the duration of abnormal elevation of the level of serum alanine aminotransferase (glutamic-pyruvic transaminase [SGPT]) was 16 weeks. The cases of non-A, non-B hepatitis could be divided into three groups according to the pattern of elevation of SGPT levels. These findings may suggest either a multiple etiology for non-A, non-B hepatitis or a variety of clinical symptoms with a single etiology for the infection.

Alanine Transaminase↗

Demonstration of hepatitis B e antigen (HBeAg) in association with intact Dane particles.

Mild detergent treatment (0.1% Sarkosyl-0.1% beta-mercaptoethanol) of Dane particle-rich fraction from human serum resulted in the release of core particles together with HBe antigen activity when examined by the reversed passive haemagglutination method. Furthermore, when the core particles isolated by the above procedure were exposed to stronger detergent (1% Sarkosyl-0.1% beta-mercaptoethanol), additional HBe antigen activity was released only from intact core particles with DNA polymerase activity and not from empty core particles.

Carrier State↗

The use of the anti-Acholeplasma activities of Streptomyces culture filtrates for the screening of new antibiotics.

A screening method for new antimicrobial agents from streptomyces culture filtrates was developed. Three different types of test organisms were used for determining the antimicrobial activities of the culture filtrates: they were (a) an antibacterial activity test against Staphylococcus aureus, (b) an antimycoplasmal activity test against Acholeplasma laidlawii, and (c) a cytotoxicity test against HeLa-S3 cells. The active filtrates showing antimicrobial spectra (anticellogram) which did not match those of known antimicrobial agents were used for further purification to obtain new antimicrobial agents. Of these screening methods, antimycoplasmal activity against Acholeplasma laidawii was the most sensitive for discriminating new compounds contained in the filtrates of known antibiotics.

Acholeplasma laidlawii↗

Anti-nucleoprotein antibody response in influenza A infection.

The nucleoprotein (NP) antigen isolated from influenza A virus by solubilization with Triton X-100 (TX-100) and further electrophoresis with SDS-cellulose acetate membrane gave a single band on SDS-polyacrylamide gel electrophoresis. Rabbit anti-serum hyperimmunized with the NP reacted only against the NP antigen. Moreover, a well-defined single precipitin line was shown between the NP and human sera. These results suggested that the NP was possible to detect anti-NP antibody in human serum. Immuno double diffusion (IDD) and single radial immunodiffusion (SRD) tests using the NP were established to detect the anti-NP antibody in human sera. During an epidemic caused by antigenic drift strain, anti-NP antibody was detected by the IDD test in the cases which did not show any significant rise in HAI titer. During a mixed epidemic caused by the different strain of HA antigen, the infection ratio in mass population was revealed more convenient and sensitive by SRD than HAI. The anti-NP antibody was detected by IDD for long periods of one year or more after infection. These results suggest that the detection of anti-NP antibody is applicable to serologic studies, particularly serologic diagnosis and serologic surveys of influenza infection in mass population.

Antibodies, Viral↗

Antiviral and interferon-inducing activities of a new peptidomannan, KS-2, extracted from culture mycelia of Lentinus edodes.

Oral (PO) administration of KS-2 to adult DDI mice resulted in a peak serum interferon (IF) titer of 800 units (U)/ml 20 hours after administration with detectable levels persisting until 30 hours. After intraperitoneal (IP) injection, a peak serum IF titer of 1,600 U/ml was detected and it followed the same time course as that of oral administration. The IF induced by KS-2 shared certain physico-chemical properties with the standard preparation of immune IF and was not neutralized by an antiserum against type I IF. In mice infected intranasally (IN) with influenza A2 (H2N2) virus, KS-2 was found to possess significant protective activities. Efficacy of the agent was evidenced by an increase in survivor number, a prolongation of mean survival time, an inhibition of the development of lung consolidation induced by the viral infection and a decrease in virus titer in lung tissues. Both PO and IP administrations of KS-2 protected mice against infection and significant antiviral activities were achieved not only by prophylactic but also chemotherapeutic administration. The protective activities of KS-2 against influenza virus infection in mice are discussed in view of the immunopotentiation of the host animals.

Agaricales↗

Effect of neocarzinostatin on microtubules.

Effect of Neocarzinostatin (NCS) on microtubules was examined both in vitro and in vivo. Although NCS had no effect on microtubule assembly in vitro nor dissociated cytoplasmic microtubular network in vivo, microtubular network appeared to be changed to coarse form in NCS-treated 3T3 and HeLa cells. Effect of NCS on microtubules was discussed in comparison with colchicine.

Animals↗

Annual examination of influenza virus infection among pigs in Miyagi prefecture, Japan: the appearance of Hsw1N1 virus.

Annual dissemination of swine and Hong Kong influenza viruses among hogs in Miyagi prefecture, Japan, was examined by virus recovery and serological tests. The serological examination revealed that two distinct influenza A viruses, H3N2 and Hsw1N1, had caused dual epidemic in pigs since mid-1977. Some individual sera contained antibodies against both strains. Although positive sera against Hong Kong or swine influenza viruses appeared in the serosurvey throughout the year, the positive ratios indicated a peak in the early spring of 1978. During this high prevalence period, positive sera against the H3N2 strain were found throughout the prefecture, but high incidences of Hsw1N1 virus were found only in limited areas to the north-east of Sendai City. Four strains of influenza A virus were isolated from bronchial swabs collected from hogs in April, 1978. These strains were identified as Hsw1N1 viruses and were closely related to the A/New Jersey/8/76 strain.

Animals↗

Isolation and characterization of influenza A viruses from wild ducks in northern Japan: appearance of HSW1 antigens in the Japanese duck population.

Twenty-six influenza A viruses were isolated from cloacal and tracheal samples of 235 resident and 396 migratory ducks in Miyagi prefecture, Japan, in 1977--78. Of these, twelve were antigenically related to the avian-origin HSW1 virus, A/duck/Alberta/35/76 (HSW1N1), but their neuraminidase antigens were characterized as Nav2-3, Nav4 or N2. These antigenic configuration have not previously been reported. In addition, one strain in which the neuraminidase antigen was identified as Nav4, was demonstrated to be a mixture of two haemagglutinins, HSW1 and Hav7. Two distinct strains were separated from the mixture and characterized as HSW1Nav4 and Hav7Nav4. The antigenic identification of an additional 13 influenza A viruses revealed the presence of six haemagglutinin subtypes (Hav1, Hav3, Hav4, Hav6, Hav7, and Hav8) and five neuaraminidase subtypes (Nav1, Nav2-3, Nav4, Neq2, and N2) in various combinations. The results suggest that the avian influenza A viruses among feral ducks may be isolated in various combinations of haemagglutinins and neuraminidase subtypes in Japan, and that feral ducks may be the site of genetic recombination occurring as a result of dual infection with different subtypes of influenza A virus.

Animals↗

Serological evidence of H1 influenza virus infection among Japanese hogs.

Classical H1 influenza firus infection among Japanese hogs was confirmed in 1978 by serological examination. Of 820 swine sera collected from July 1977 to February 1979 in Miyagi Prefecture, northern Japan, six sera were found to contain haemagglutination inhibition (HI) antibodies to the A/FM/1/47 (H1N1) strain. Of the six sera, one showed a significant high HI antibody titre, which was classified as IgM, to the FM1 strain, but not the other H1N1 variants. These results strongly suggest that hogs may carry an old type of H1 influenza virus. The possible role of pigs as a reservoir of human pandemic influenza strains is discussed.

Animals↗

[A survey of Brucella canis infection in dogs sheltered in Tohoku University School of Medicine (author's transl)].

A total number of 1549 dogs from Miyagi Prefecture and the north coast area of Fukushima Prfecture were surveyed during a year from December 1976 to November 1977 for Brucella canis (B. canis). 173 of 1549 dogs (11.2%) were sero-positive to B. canis, and B. canis was isolated from 55 of 148 dogs examined, giving more than 3.6% for total 1549 dogs. The positivity were higher than that have been reported from other areas. The results of the morphological and biochemical studies for isolates were similar to the reference strain RM6/66, and they were identified as B. canis. No significant difference in sero-positive rate was found between male and female, but isolation rate was higher in female than in male. B. canis was isolated most frequently from the uterus and the spleen of both sexes. The importance of urine and milk as a source of infection was discussed as well as the role of infected focus at non gravid uterus for abortion and fetal infection. A case supposed to be a vertical infection was described also.

Animals↗

Hepatitis "C" antigen in non-A, non-B post-transfusion hepatitis.

Evidence for a new hepatitis-specific antigen has been obtained from double immunodiffusion assays between acute and convalescent sera obtained from patients with non-A, non-B post-transfusion hepatitis. The designation hepatitis C (HC) antigen is proposed. HC was found in the acute-phase sera of all 13 non-A, non-B post-transfusion hepatitis patients with longer incubation and duration periods (type 2) tested, but only transiently in 4 out of 10 acutephase sera obtained from patients with type 1 non-A, non-B hepatitis, with shorter incubation and duration periods. The antigen was also detected in 2 out of 16 single specimens obtained during the acute phase from acute hepatitis patients who had not received a blood-transfusion. This suggests presence of a carrier state. No patients with alcoholic hepatitis and no healthy blood-donor carried HC antigen. The antigen seems distinct from those of hepatitis A and B (surface and core). It migrated in the serum beta-globulin region and had a buoyant density of 1.30 and a molecular weight between 100 000 and 300 000. Antibodies against HC antigen were found in only 30% of the type-2 non-A, non-B post-transfusion hepatitis patients and did not persist for long. However, these antibodies were directed specifically against HC antigen and moved in a manner similar to 7S globulin on rate-zonal centrifugation.

Acute Disease↗