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Biomedical subjects

K Terao

Publications and source records attributed to K Terao.

At least 145 records · Page 8Linked to original sources
PubMed1984

Liver injuries induced by cyclochlorotine isolated from Penicillium islandicum.

Sequential morphological changes in murine liver induced by cyclochlorotine (CC), a secondary metabolite of Penicillium islandicum were investigated by transmission electron microscopy and scanning electron microscopy. Within 15 min after the administration of CC there was a marked dilatation of Disse's space around the portal triads, and the exudates then poured out into the space which was formed by the invagination of the hepatocyte plasma membrane. Shortly after the invagination was completed, the connection between Disse's space and the invaginated space was pinched off, so that this space became a membrane-bound vacuole. After dehydration, the vacuoles became granular. The liver injuries induced by CC were influenced by various pretreatments. The results indicate that drug-metabolizing systems mediated by cytochrome p-450 in the hepatocytes may play an important role in the hepatotoxicity of CC.

Aging↗
PubMed1983

Ribosomal proteins cross-linked to 28-S and 18-S rRNA separated by sedimentation after ultraviolet irradiation of rat-liver ribosomes.

Rat liver 80-S ribosomes, irradiated with 254 nm ultraviolet light for 15-60 min (0.63-2.5 X 10(5) quanta/ribosome), were treated with sodium dodecyl sulfate; 18-S and 28-S RNA fractions were isolated by sucrose density-gradient centrifugation. The protein moieties of the 18-S and 28-S rRNA fractions were labeled with 125I. After digestion of the rRNA fractions with RNase A and T1, the cross-linked proteins were analyzed by two-dimensional acrylamide gel electrophoresis and then autoradiography. Cross-linked proteins were examined further by dodecyl sulfate/acrylamide gel electrophoresis of individual radioactive spots of proteins and their proteolytic peptides on two-dimensional gels. The results showed that S2 and S15 were cross-linked to 18-S rRNA, and L5, L6 and L8 to 28-S rRNA. Similar results were obtained when isolated 40-S or 60-S subunits were irradiated.

Animals↗
PubMed1983

Immunological characteristics of anti-A and anti-B blood group antibodies in the cynomolgus monkey.

Anti-A and anti-B blood group antibodies in the cynomolgus monkey sera were serologically characterized. 2-Mercaptoethanol (2-ME) inactivated these antibodies of both group-A and group-B sera. Furthermore, soluble human ABH substances neutralized these antibody activities. However, these activities were not inhibited by anti-human IgG or IgA serum but by anti-human IgM serum. By gel filtration on Sephacryl S-300, the anti-A and anti-B antibodies reacting readily in saline media were detected in the fractions corresponding to the IgM antibodies. Thus, anti-A and anti-B antibodies in group-B and group-A sera were judged to be mainly of IgM. In contrast to group-A and group-B sera, group-O serum contained IgG antibodies of high titers besides IgM antibodies. Neither 2-ME nor anti-human IgM serum affected these antibody activities. On the basis of the results of the inhibition test using anti-human immunoglobulin sera as well as of gel filtration, group-O sera were divided into the following two categories, the one having only IgG reacting well in the Coombs method and the one having both IgM and IgG.

ABO Blood-Group System↗
PubMed1983

The placental transfer of IgG in the cynomolgus monkey.

The placental transfer of IgG from the mother to her fetus was investigated with colony-bred cynomolgus monkeys. Very low levels of IgG were detected in sera of 84 days old fetus, indicating that transplacental transfer of IgG had started by this fetal age. Afterwards, gradual increase in the IgG level continued till 140 days of fetal age. A marked increase in the level was noted after 140 days of fetal age, during the last 4 weeks of full gestation term. Fetal anti-measles antibody increased in a pattern similar to that in the IgG level. The IgG level and anti-measles and anti-streptolysin O antibody titers of newborns never exceeded those of their mothers.

Animals↗
PubMed1983

Immunoglobulins and measles antibody in sera of newborn cynomolgus monkeys and in milk of their mothers.

The changes in the serum immunoglobulin (Ig) level and in the measles antibody titer were examined with colony-born infant cynomolgus monkeys from 0 day to 26 weeks in age. In addition, their mother-monkey's milk was analyzed for Ig. The decrease in the IgG level after birth was more remarkable in the infants born with high IgG levels than those born with low IgG levels. The IgM level prominently increased for the first 3 weeks after birth in the infants born with low IgG levels, while the increase was not so prominent in those born with high IgG levels. Anti-measles antibody titers decreased linearly with a half-life of 3.4 +/- 0.4 weeks after birth regardless of the titer at birth. A significant amount of IgA, a very small amount of IgM and little IgG were detected in the milk collected just after parturition. Ig of any class was no longer found in the milk collected one to 6 weeks after parturition. These results suggest that the initial level of transplacentally transferred IgG must be one of the important factors influencing the subsequent development of infant monkey's own immunoglobulin synthesis.

Animals↗
PubMed1983

Anti-A and anti-B blood group antibody levels in relation to age in cynomolgus monkeys.

Anti-A and anti-B blood group antibody levels were determined with serum samples of 583 cynomolgus monkeys of group-A and group-B, aged from 4 days to 15 years or more. Eight group-A infants free from anti-B antibody at ages of 4 to 25 days were consecutively followed up for the appearance of anti-B antibody. It appeared at ages between 68 and 160 days. Both anti-A and anti-B levels rose with increase in the age and reached a maximum at the age of 4 to 5 years. After that the levels gradually fell with aging.

ABO Blood-Group System↗
PubMed1983

Duck hepatitis B virus and liver diseases.

The presence of duck hepatitis B virus in serum was studied in 61 ducks (24 from Chi-tung county, China, 20 from Changchun, China, and 17 from Chiba, Japan) with relation to liver disease. None of the 37 ducks from Chiba and Changchun was positive for duck hepatitis B virus as assayed by electron microscopy, endogenous deoxyribonucleic acid-polymerase activity, and hybridization with duck hepatitis B virus deoxyribonucleic acid. No liver disease was seen in these ducks. In contrast, viruslike particles were present in the serum of 12 of 24 (50%) ducks from Chi-tung, China. The presence of duck hepatitis B virus in serum was indicated by the hybridization spot test and deoxyribonucleic acid-polymerase activities. A variety of liver diseases including chronic hepatitis and cirrhosis were seen in the livers of a majority of the ducks from Chi-tung. One duck hepatitis B virus-positive duck had multicentric hepatocellular carcinoma with underlying cirrhosis. Comparison of serum duck hepatitis B virus markers and liver disease in the affected flock revealed a tendency for seronegative ducks to have advanced liver diseases. Duck hepatitis B virus infection may be used as an experimental model to test various hypotheses concerning the pathogenesis of hepatitis B virus-associated liver disease in humans.

Animals↗
PubMed1983

Inhibitory effect of fumaric acid on 3-methyl-4'-(dimethylamino)-azobenzene-induced hepatocarcinogenesis in rats.

Fumaric acid (FA) was examined for its effect on hepatocarcinogenesis in rats fed 3-methyl-4'-(dimethylamino)azobenzene (3-Me-DAB). Male DONRYU rats were given approximately 0.5 g 3-Me-DAB by being fed a diet containing 0.06% 3-Me-DAB for 50 days; they were then given a diet containing 1% FA and drinking water containing 0.025% FA for 51 weeks. The administration of FA effectively suppressed the development of hepatocellular carcinoma, hyperplastic nodules, and hyperplastic areas in the livers of rats fed 3-Me-DAB.

Animals↗
PubMed1982

Identification of the protein cross-linked to 3'-terminus of 5 S RNA in rat liver ribosomal 60 S subunits.

To cross-link the 3'-terminus of 5 S RNA to its neighbouring proteins, ribosomal 60 S subunits of rat liver were oxidized with sodium periodate and reduced with sodium borohydride. 5 S RNP was then isolated by EDTA treatment followed by sucrose density-gradient centrifugation and subjected to SDS-polyacrylamide gel electrophoresis. The protein with a slower mobility than the L5 protein, which was thought to be cross-linked 5 S RNP, was labeled with 125I, treated with RNAase, and analyzed by two-dimensional polyacrylamide gel electrophoresis, followed by radioautography. A radioactive spot located anodically from L5 protein was observed, suggesting that it is the L5 protein-oligonucleotide complex. When analyzed by SDS slab polyacrylamide gel electrophoresis followed by radioautography, the peptide pattern of the alpha-chymotrypsin digest of this 125I-labeled protein-oligonucleotide complex was similar to that of the digest of 125I-labeled L5 protein. The results indicate that L5 protein binds to the 3'-terminal region of 5 S RNA in rat liver 60 S subunits.

Animals↗
PubMed1982

Interaction of 5S RNA-L5 protein complex with 40S subunits in rat liver ribosomes.

When rat liver 80S ribosomes or polysomes were dissociated into their subunits by EDTA-treatment, a 5S RNA-L5 protein complex was present in EDTA-derived small subunits, and released from the subunits by urea. The interaction of 5S RNP with the small subunits did not occur in the case of 80S couples formed from 40S and 60S subunits in the presence of Mg2+, indicating that the attachment of 5S RNP to EDTA-derived small subunits was not an artifact caused by the unfolding of the subunits. These results give direct evidence that 5S RNP is located at the interface between large and small subunits, and suggest that 5S RNP binds to the 40S subunit in the functioning polysomes, but not the 80S couples.

Animals↗
PubMed1982

Age-related immunoglobulin levels in cynomolgus monkeys.

Serum immunoglobulin levels were measured with 144 domestically-bred cynomolgus monkeys, aged 0 day to 18 years. IgG level of the newborn just after birth was somewhat lower than that of their mother monkeys, continuing to decrease for 3 postnatal months. Thereafter, the level began to increase gradually till 4 to 5 years when an adult level was attained. IgA was detected on the day of birth in half of the animals and started to increase soon after birth, reaching an adult level in 5 to 6 years. A relatively low level of IgM was detected in all animals at birth. The increase of IgM level continued till 5 years of age. These patterns of immunoglobulin levels related to age are very similar to those of rhesus monkeys and human.

Age Factors↗
PubMed1982

[Antitumor effects of polyamine synthesis inhibitors based on major premise of treatment for human malignant tumor].

The polyamine synthesis inhibitors--alpha-difluoromethylornithine (DFMO) and methylglyoxal bis (guanylhydrazone) (MGBG)--were put to antitumor tests based on the premise of treatment for human gastrointestinal cancer. The both drugs were administered intraperitoneally to BALB/c nude mice xenoplanted human gastric cancer for 10 consecutive days. Both marked antitumor effects and side effects were observed in mice treated at the dosage of DFMO 500 mg/kg/day and/or MGBG 50 mg/kg/day and/or MGBG 30 mg/kg/day brought about significant antitumor effects as well as less side effects. Microscopic observation revealed antitumor actions of these drugs as cytostatic rather than cytocidal. Tumor regrowth after the termination of this combined treatment, however, was noticed. Judging from these data, the both drugs may be effective against human gastrointestinal cancer with minor side effects.

Animals↗
PubMed1981

Identification of neighboring protein pairs cross-linked with dimethyl 3,3'-dithiobispropionimidate in rat liver 40S ribosomal subunits.

Rat liver 40S ribosomal subunits were treated with a bifunctional imidoester, dimethyl 3,3'-dithiobispropionimidate (DTP), and the neighboring protein pairs were identified. The cross-linked proteins were analyzed by acrylamide/SDS diagonal gel electrophoresis (Sommer & Traut (1974) Proc. Natl. Acad. Sci. U.S. 71, 3946-3950). The cross-linked components that fell off the diagonal upon adding 2-mercaptoethanol in the second dimension were labeled with 125I in the acrylamide gel and identified by two-dimensional acrylamide/urea gel electrophoresis, followed by radioautography. Considering these results and the molecular weights, we propose the following ten pairs, according to our numbering system (Terao & Ogata (1975) Biochim. Biophys. Acta 402, 219-229): S3-S5 (S3/S3a-S4), S3-S14 (S3/S3a-S14), S3-S17 (S3/S3a-S16), S5-S22 (S4-S23/S24), S10-S12 (S8-S11), S9-S16 (S9-S18), S9-S22 (S9-S23/S24), S6-S23 (S5-S25), S17-S21 (S16-S19), and S16-S26 (S18-S27). The designation according to the proposed uniform nomenclature (McConkey et al. (1979) Mol. Gen. Genet. 169, 1-6) are given in parentheses.

Animals↗
PubMed1981

Detection of ABO group-specific substances on the red cells of the cynomolgus monkey.

Several attempts were made to demonstrate the presence of ABO blood group substances on the red blood cells (RBC) of the cynomolgus monkey. Neither the direct hemagglutination test nor the antibody absorption test was successful in detecting these substances from whole RBC, the stromata or the butanol extracts of RBC. By the heat elution of antibodies, however, the presence of ABH substances was demonstrated on RBC of every phenotype without fail. In all cases, there was a reciprocal relationship between the ABH substances of RBC and of saliva and the anti-A and anti-B antibodies in serum, being in good agreement with Landsteiner's rule. Accordingly, it can be concluded that a small amount of ABH substances must be present on RBC of the cynomolgus monkey.

ABO Blood-Group System↗