Search PubMed⌕ Search

Biomedical subjects

T Mikami

Publications and source records attributed to T Mikami.

At least 595 records · Page 33Linked to original sources
PubMed1987

Detection of fish antibody against protein antigen of Aeromonas salmonicida by enzyme-linked immunosorbent assay using biotin-avidin system.

Antibody against Aeromonas salmonicida was detected in sera from immunised or experimentally infected rainbow trout by enzyme-linked immunosorbent assay (ELISA) using the biotin-avidin system. The ELISA titre correlated well with the agglutinin titres of the sera, but the ELISA was found to be more sensitive than the agglutination test. When the rainbow trout serum was separated by column chromatography, antibody activity (determined by ELISA and agglutination test) was detected in the IgM fractions. Minimum cross reaction was observed in the ELISA system between antigen prepared from A salmonicida and antibodies against Vibrio species and other species of Aeromonas. The specificity of the ELISA was also confirmed by inhibition test. Immunisation of rainbow trout with a virulent strain of A salmonicida provided good protection, though no correlation was observed between the protection and the ELISA titres of sera.

Aeromonas↗
PubMed1986

Heterogeneity of circular mitochondrial DNA molecules from sugar beet with normal and male sterile cytoplasms.

Mitochondrial (mt) DNAs from normal (N) and male sterile (S) cytoplasms of sugar beet have been isolated and investigated by electron microscopy. The results showed that mtDNA was composed of a heterogeneous population of circular molecules. Their contour lengths varied from 0.28 to 51 micron, but unlike in the case of maize, a large difference was not observed in the distribution of molecular classes greater than 1.0 micron between N and S cytoplasms of sugar beet. On the other hand, N and S cytoplasms were shown to contain their own characteristic combinations of small circular mtDNA species with lengths between 0.28 micron and 0.6 micron. Mitochondrial DNAs from various sources of male-sterile cytoplasms were analyzed by agarose gel electrophoresis to determine the extent of cytoplasmic variation. Additional low molecular weight DNA bands appeared in all male-sterile lines examined, and as a result, three distinctive banding patterns were recognized. These data are in general agreement with those based upon restriction endonuclease digestion of mt and chloroplast DNAs and the genetic analysis of fertility restoration in test crosses.

Cytoplasm↗
PubMed1986

A comparison of the biological properties of type 2 plaque-producing agent derived from the Cal-1 strain of Marek's disease virus with other related viruses.

The serological and biological properties of the type 2 plaque-producing agent (PPA) derived from the Cal-1 strain of Marek's disease virus (MDV) were compared with those of reference strains of the three serotypes of MDV and herpesvirus of turkeys (HVT) groups; namely JM, HPRS-24 strains of MDV and the FC-126 strain of HVT for serotype 1, 2, and 3, respectively. By agar gel precipitation (AGP), indirect fluorescent antibody and virus neutralization tests, type 2 PPA was related but not identical to the FC-126 strain. By the AGP test, type 2 PPA showed a poor ability to synthesize B antigen and the A antigen was different from that of strain FC-126. To compare the virological characteristics of type 2 PPA with the reference strains, the release of cell-free virus into supernatants of infected cell cultures and titers of cell-free virus extracted sonically from infected cell cultures were examined. Cell-free type 2 PPA virus was easily detected in the supernatants and extracted from infected cell cultures. These properties were similar to reference strains of serotype 2 and 3. Next, the structural similarities of viral DNAs of type 2 PPA and strain FC-126 were examined by Southern blot hybridization. The restriction endonuclease-cleavage patterns of DNA of type 2 PPA were very similar but not identical to those of the FC-126 strain. In chickens inoculated with type 2 PPA, splenic lymphocytes supported a non-productive latent infection as did also those from chickens inoculated with the FC-126 or HPRS-24 strains. From these results, type 2 PPA appears to belong to serotype 3 of MDV and HVT groups. The origin of type 2 PPA is discussed.

Animals↗
PubMed1986

Similarities and dissimilarities in the structure and expression of viral genomes of various virus strains immunologically related to Marek's disease virus.

Various strains immunologically related to Marek's disease virus (MDV) have been subdivided into three serotypes: serotype 1, pathogenic strains of MDV and attenuated or apathogenic variants derived from them; serotype 2, naturally occurring apathogenic strains of MDV; serotype 3, herpesvirus of turkey (HVT). The viral genome structures of these three serotypes were compared by a simple, practical method using total DNA extracted from virus-infected cells instead of viral DNA purified from virions. The restriction endonuclease-cleavage patterns of serotype 2 viral DNA were found to differ from those of either serotype 1 MDV or serotype 3. Under stringent conditions, no significant DNA homology was detected among the three serotype viruses, except in a restricted portion of these viral genomes. Northern blot hybridization experiments suggested that virus-specific polyadenylated RNA of about 2.4 kilobases was transcribed from a restricted portion showing close homology in these viruses. Southern blot hybridization under less stringent conditions revealed that regions with weak homology were distributed over most of the viral genomes of the three serotypes. Two types of virus-specific glycoproteins, gA and gB, were identified in the immunoprecipitates of the culture medium and cell lysates, respectively, of serotype 2-infected cultures with monoclonal antibodies or hyperimmune antisera cross reactive with serotype 1 MDV and serotype 3 HVT, and detected on the surface of serotype 2-infected cells by the membrane immunofluorescence test. These results indicate a close evolutionary relationship among these three viral serotypes.

Animals↗
PubMed1986

Establishment of a variant type of turkey herpesvirus which releases cell-free virus into the culture medium in large quantities. Brief report.

A variant turkey herpesvirus (HVT/VT) which releases 10(5.0) plaque-forming units per 0.1 ml of cell-free virus into the culture medium was established from the prototype HVT FC 126 strain (HVT/WT). Many enveloped and naked virions of HVT/VT but only naked virions of HVT/WT were found in the culture medium. By the HindIII restriction cleavage patterns, the HVT/VT DNAs were almost identical to those of HVT/WT. The HVT/VT was replication-defective in chickens.

Animals↗
PubMed1986

Non-invasive ultrasonic measurement of the elastic properties of the human abdominal aorta.

A new echo tracking device linked to real time ultrasonic B mode equipment was developed to measure non-invasively the elastic properties of the human abdominal aorta. Pulsatile diameter change and mean diameter of the abdominal aorta were measured in 61 subjects with this ultrasonic device. Strain and pressure-strain elastic modulus Ep were calculated from pulsatile diameter change, diameter, and pulse pressure obtained by the auscultatory method. Strain significantly decreased with age; 0.076(0.024) (mean(SD)) in group 1 (20 young adults below the age of 35 years); 0.048(0.024) in group 2 (21 middle aged subjects between the ages of 35 and 60 years); and 0.030(0.010) in group 3 (20 elderly subjects over the age of 60 years). Ep values were 0.99(0.34) X 10(5), 1.55(0.68) X 10(5), and 3.80(2.05) X 10(5) N X m-2 in groups 1, 2, and 3 respectively. Ep in group 3 was significantly higher than in groups 1 and 2. The regression equation relating Ep to age was Ep = (-0.72 + 0.058 X age) X 10(5) N X m-2 (r = 0.73). The Ep value and its age related increase agreed with the findings in postmortem arteries. The elastic properties of the abdominal aorta could, therefore, be determined non-invasively by this ultrasonic method.

Aorta, Abdominal↗
PubMed1986

Monoclonal antibody to chicken fetal antigen on Marek's disease lymphoblastoid cell line MDCC-MSB1.

A monoclonal antibody (2H3) to chicken fetal antigen (CFA) expressed on the cell surface of the Marek's disease lymphoblastoid cell line MDCC-MSB1 was generated. 2H3 reacted specifically with various cells from chicken embryos, especially with fetal red blood cells, fetal bursa-derived lymphocytes, fetal liver cells, and embryo fibroblasts but not with fetal peripheral blood lymphocytes. 2H3 reacted also with all lymphoblastoid cell line cells tested: Marek's disease, avian leukosis, and reticuloendotheliosis line cells. On the basis of 2H3 specificity, CFA detected by 2H3 seemed to be similar to chicken fetal red blood cell antigen previously reported, but not to chicken alpha-fetoprotein. A transient increase of reactivities with 2H3 was observed in lymphocytes prepared from thymus, spleen, and bursa of chickens inoculated with Marek's disease virus or herpesvirus of turkeys from 7 to 21 days postinoculation. The average percentage of CFA-positive cells in lymphoid cells from Marek's disease virus-infected chickens at the peaks was higher than that of the cells in Marek's disease tumor cells from 146- and 156-day-old chickens in the field. The results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analysis revealed that the monoclonal 2H3 is recognized a Mr 50,000 oncodevelopmental cell surface antigen present on MDCC-MSB1 cells. The possible differences between CFA detected by 2H3 and chicken fetal red blood cell antigen expressed on normal chicken fetal erythrocytes are discussed.

Animals↗
PubMed1986

Detection of a new antigen associated with chicken thrombocytes on Marek's disease lymphoblastoid cell line.

A monoclonal antibody, 2C12, produced against MDCC-MSB1 cells, reacted with several cell lines derived from Marek's disease (MD), including MDCC-MSB1 cells, normal chicken thrombocytes, and MD tumor cells. It did not react with cell lines derived from avian leukosis or reticuloendotheliosis, cells from normal chicken thymus and bursa, chicken kidney cells and quail fibroblast cultures inoculated with MD virus, or with erythrocytes from 1-day-old and adult chickens, cow, sheep, and horse. Anti-thrombocyte serum prepared in a rabbit reacted with thrombocytes and MDCC-MSB1 cells. The specificities of antibody 2C12 and anti-thrombocyte serum against MDCC-MSB1 cells and thrombocytes were confirmed by cross-absorption, blocking, and double-membrane fluorescent antibody tests. The existence of a polypeptide with an apparent molecular weight of 103,000, common to both MDCC-MSB1 cells and thrombocytes, was demonstrated by Western blotting analyses.

Animals↗
PubMed1986

Phagocytic activity of macrophages of rainbow trout against Vibrio anguillarum and the opsonising effect of antibody and complement.

The phagocytosis of Vibrio anguillarum by peritoneal macrophages from normal rainbow trout was enhanced by antibody and complement. Treatment of either macrophages or the bacteria by antibody also enhanced opsonisation. Five weeks after immunisation with V anguillarum, the phagocytic activity of macrophages from rainbow trout was increased significantly compared with the activity of those from unvaccinated fish. Although agglutinin titres did not increase until three weeks after immunisation, seven out of 10 fish challenged one week after immunisation survived, indicating that immunised fish had developed resistance to vibrio infection before significant levels of antibody or phagocytic activity became detectable.

Animals↗