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Biomedical subjects

N Hirano

Publications and source records attributed to N Hirano.

At least 145 records · Page 8Linked to original sources
PubMed1983

Persistent, tolerant or subacute infection in Borna disease virus-infected rats.

The rabbit-adapted Borna disease (BD) virus strain V was passaged by intracerebral infection of 1-day-old Wistar rats. Infectivity titres reached 10(8) infectious units per gram of brain 4 weeks after infection. No clinical signs were evident. The persistent infection could be induced with adapted or field strains of BD virus. Strains were identified by neutralization tests. The virulence of the rabbit-adapted BD virus for the rat increased with rat passages. The 5th passage induced clinical symptoms in animals infected at 1 week of age or older. Between 20% and 50% of diseased rats died. Virus-specific antigen was detectable immunohistologically in neurons of rats infected at all ages. Animals inoculated at 1 or 2 months of age, but not the neonatal rats, showed signs of inflammation in the brain. Infected rats produced specific antibodies. In the older groups (infected at ages of 1 or 2 months), and especially in surviving animals, occasionally, neutralizing antibodies with high titres were found. Transfer of primed spleen cells resulted in subacute disease. These findings demonstrate that neonatal rats can acquire a persistent, tolerant infection and that expression of disease is mediated by immunological factors.

Animals↗
PubMed1981

Persistent infection with mouse hepatitis virus, JHM strain in DBT cell culture.

After inoculation with JHM strain into DBT cell monolayers, a persistently infected DBT cell culture was established without producing typical cytopathic changes after about 15th passages. By immunofluorescence virus specific antigen was demonstrated in 10 to 15% DBT cells. This persistently infected culture (JHM-CC) was resistant to superinfection with parental JHM, but such resistance was not shown against vesicular stomatitis virus. JHM-CC virus produced small plaques on DBT cell monolayers. Temperature sensitive (TS) mutant, defective interfering (DI) particle or interferon was not detected in the JHM-CC. To intracerebral inoculation with JHM-CC virus, cortisone treated ICR mice survived without showing clinical signs, however, demyelinating lesions were produced in the brain and spinal cord of them.

Animals↗
PubMed1981

Electron microscopy of massive cerebrocortical necrosis in suckling rats inoculated intracerebrally with mouse hepatitis virus, A59 strain.

Cerebrocortical lesions produced in suckling rats by intracerebral inoculation with MHV-A59 was studied by electron microscopy. Many cytoplasmic vesicles and irregular patterns of the nuclear membrane were observed in infected neurons at 48 h post-inoculation (p.i.). The abnormally electron-lucent or -dense neurons were seen at 72 h p.i., and in the formers, many virions were detected between the outer and inner nuclear membranes as well as in the dilated endoplasmic reticulum cisternae. Both reticular and tubular inclusion bodies appeared in the cytoplasm and some virions seemed to be associated with an end of the latter. Many virions were also seen in the intercellular spaces. At 96 h p.i. many virions were present not only in the cytoplasm of degenerated neurons but also in astrocytes appearing in the spongy lesions. There was also degeneration of oligodendrocytes while having no virions. In rats which survived the acute phase of infection and were killed at 8 days or 14 days p.i., many macrophages and fibroblasts were accumulated in the thickened leptomeninges and submeningeal area. At 22 days p.i., atrophied electron-dense neurons having no virions were scattered throughout the cerebral cortex.

Animals↗
PubMed1981

Tumor-associated serum proteins in rats as detected by two-dimensional gel electrophoresis.

The sera from normal and tumor-bearing rats were separated by polyacrylamide gel disc isoelectric electrophoresis and then in a perpendicular dimension by polyacrylamide gel slab electrophoresis with a gradient from 4% to 20%. When the gel was stained with Coomassie brilliant blue, 100-150 components were separately observable with normal serum. With the sera from Rhodamine sarcoma-bearing rats, three more components were detected with a high reproducibility. They were of pI (isoelectric point) 4.5 and Rm (relative mobility) 0.63, of pI4.8 and Rm 0.63 and of pI 4.9 and Rm 0.75. The 4.5/0.63 (pI/Rm) and the 4.8/0.63 components appeared soon after transplanting the tumor, whereas the 4.9/0.75 component appeared at the late stage of its growth. Upon surgical removal of the grown tumor, the former two components disappeared rapidly, while the latter component disappeared gradually. Similar results were obtained with Yoshida sarcoma, and ascites hepatoma AH66 and AH130. A 3rd polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate revealed that the 4.5/0.63 and the 4.8/0.63 components were each composed of a single polypeptide of approximately 64,000 daltons, and that the 4.9/0.75 component was composed of two different polypeptides of approximately 33,000 daltons and approximately 10,000 daltons. It was confirmed by an immunodiffusion experiment that none of these three proteins was alpha-fetoprotein.

Animals↗
PubMed1980

Analysis of serum iron by gel permeation high-performance liquid chromatography.

A high-performance liquid chromatographic procedure for the determination of serum iron is reported. Serum iron extracted with methyl isobutyl ketone was converted to dibenzoylmethane chelate (molecular weight 725), and it was separated from excess dibenzoylmethane (molecular weight 224) by gel permeation chromatography. The chelate was determined by measuring ultraviolet absorption at 280 nm. Good reproducibility, recovery, and correlation with the conventional colorimetric method were observed.

Chromatography, High Pressure Liquid↗
PubMed1980

Hydrocephalus in suckling rats infected intracerebrally with mouse hepatitis virus, MHV-A59.

After intracerebral inoculation of mouse hepatitis virus, MHV-A59 strain, into 3- to 5-day-old Wistar rats, some survivors at 14 days postinoculation (p.i.) were found to lack the cerebral cortex and to have an accumulation of considerable amount of cerebrospinal fluid. The virus titer in the brain increased exponentially after inoculation, reaching a maximum 4 to 6 days p.i. when immunofluorescence revealed virus-specific antigen within neurons in the cerebral cortex. A small amount of infectious virus was also detectable 14 days p.i. when the cerebral anomaly was evident. This brain malformation causing hydrocephalus was due to cerebral damage by viral infection.

Age Factors↗
PubMed1978

Physico-chemical properties of mouse hepatitis virus (MHV-2) grown on DBT cell culture.

Some properties of a strain of mouse hepatitis virus, MHV-2, grown on DBT cells were determined using a plaque assay on the cells. Viral growth was not inhibited by the presence of actinomycin D or 5-iodo-2-deoxyuridine. MHV-2 was completely inactivated by ether, chloroform, sodium deoxycholate or beta-propiolactone, but showed a moderate resistance to trypsin. Heating at 56 C for 30 min did not completely abolish the virus infectivity. The virus was stable after heating at 50 C for 15 min in 1M-MgCl2 or 1M-MgSO4 as well as at 37 C for 60 min at pH 3.0 to 9.0. Infectivity was decreased to 1/100 and 1/400 after storing at 4 C for 30 days and 37 C for 24 hr, respectively. The virus passed through a 200-nm but not a 50-nm Sartorius membrane filter. The buoyant density of MHV-2 was 1.183 g/cm3 in sucrose gradient, and the fraction contained coronavirus-like particles measuring 70 to 130 nm in diameter. Survival rate was 10% after exposure to ultraviolet at 150 ergs/mm2. Freezing and thawing or sonication at 20 kc for 3 min did not affect the virus titer. No hemagglutinin was demonstrable with red blood cells of the chicken, Japanese quail, mouse, rat, hamster, guinea pig, sheep, bovine or human.

Cell Line↗
PubMed1977

Polyadenylate in the virion RNA of mouse hepatitis virus.

Mouse hepatitis (MH) virus was grown in SR-CDF1-DBT, a mouse cell line, and purified by ammonium sulfate precipitation and by density gradient centrifugation. Extraction of RNA from purified virions with 1% SDS and sedimentation analysis of the RNA revealed a major 50S component and two minor components. Treatment of virions with phenol/chloroform also produced the 50S component, although its yield was lower. MH virion RNA can bind to a poly(U)-fiberglass filter, indicating that MH virion RNA contains poly(A). A poly(A)-like fragment was isolated by digestion with ribonuclease A [EC 3.1.4.22] and T1 [EC 3.1.4.8] and by DEAE-Sephadex column chromatography. Analysis of the fragment for base composition showed it to be an adenine-rich material. Its chain length was about 90 nucleotides, as determined by ion-exchange chromatography and gel electrophoresis.

Cell Line↗