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Biomedical subjects

K Terao

Publications and source records attributed to K Terao.

At least 127 records · Page 7Linked to original sources
PubMed1988

The simian-type M and the human-type ABO blood groups in the African green monkey (Cercopithecus aethiops): their inheritance, distribution and significance for the management of a breeding colony.

We have established a new simian-type blood group system (M blood groups) in the African green monkey (Cercopithecus aethiops), using a haemagglutinating antibody which was developed by alloimmunization. The M blood groups consisted of two phenotypes, type-M and type-m. We have also determined the mode of inheritance as well as the distribution of both simian-type M and human-type ABO blood groups, employing 113 families including 160 animals. The family analysis revealed that (1) the simian-type M blood groups were governed by the two alleles, dominant M and recessive m, and (2) the human-type ABO blood groups were governed by 3 alleles, codominant A and B and silent O, although no monkey of phenotype-O was found in our breeding colony. Differences in the phenotypic distribution and gene frequency of respective M and ABO blood groups were observed among 3 populations imported at different times. The genetic management of the African green monkey breeding colony was discussed in relation to the difference in distribution of phenotypes of M and ABO blood groups between the parental (wild-originated) and the first filial (colony-born) populations.

ABO Blood-Group System↗
PubMed1988

The serodiagnosis of Campylobacter infection in infant cynomolgus monkeys (Macaca fascicularis) 2 to 18 weeks old by enzyme-linked immunosorbent assay.

We established the enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to Campylobacter and applied it in defining the period of the primary infection of Campylobacter in infant cynomolgus monkeys (Macaca fascicularis). The antibody to Campylobacter spp. could be detected with only 0.25 mul of serum by using commercially available antigens and anti-cynomolgus monkey IgG antibody conjugated with alkaline phosphatase. The inhibition experiments using extracts of C. jejuni, C. fetus and Yersinia enterocolitica demonstrated that the established ELISA system could detect species-specific anti-C. jejuni and anti-C. fetus antibodies. The levels of antibodies to both C. jejuni and C. fetus were high in 2 weeks old infant cynomolgus monkeys, rapidly decreasing until 6 to 14 weeks of age. This result indicates that the antibodies detected in 2 week old infants were IgG antibodies of maternal origin transferred through placenta. The C. jejuni was isolated from infants when the level of maternal antibody became the lowest. Infant cynomolgus monkeys obviously developed IgG antibodies to C. jejuni within 4 weeks after infection. On the other hand, no antibody response to C. jejuni was found in two infants from which it could not be isolated throughout the observation period. As regards C. fetus infection, infants showed a poor antibody response although it was more frequently isolated than C. jejuni. In conclusion, the ELISA system established in the present study is useful for the serological diagnosis of C. jejuni infection during infancy in the cynomolgus monkey.

Animals↗
PubMed1988

Increased vascular permeability in the thymus of the autoimmune New Zealand mouse.

The thymus glands of non-autoimmune BDF1 and C3H mice and autoimmune NZB/WF1 mice were studied histologically at intervals ranging from one hour to 60 days after systemic administration of carbon. In NZB/WF1 mice over 9 weeks of age, many circulating carbon-laden macrophages were seen to have penetrated the walls of blood vessels, and to have then entered the thymic parenchyma. Carbon was also taken up by many perivascular macrophages stretched out along blood vessels and by many resident tissue macrophages scattered throughout the thymic parenchyma. In contrast, no carbon was seen at any time in the extravascular tissues of the thymus in BDF1 and C3H mice of comparable age. These results indicate a great increase in the permeability of blood vessels in the thymus of NZB/WF1 mice. This increase in carbon permeability occurs both in the cortex and the medulla, particularly at the corticomedullary junction. There is little increase in the permeability to carbon in NZB/WF1 mice at the age of 4 weeks, suggesting that the increase in vascular permeability begins between the ages of 4 and 9 weeks. The possible role of this greatly increased blood vessel permeability in the thymus on the aetiology and pathogenesis of autoimmune disease is discussed.

Animals↗
PubMed1987

Hepatic ultrastructural changes and liver dysfunction in amyotrophic lateral sclerosis.

Ultrastructural changes of hepatocytes were studied in liver biopsy specimens obtained from 21 patients with amyotrophic lateral sclerosis (ALS). In all specimens, one or more of the following abnormal findings were made: bizarre giant mitochondria; intramitochondrial paracrystalline inclusions; disorganization of the lamellar structure of rough endoplasmic reticulum; increased numbers of smooth endoplasmic reticulum; and/or parasinusoidal fibrosis. Above all, paracrystalline inclusions appeared to be a highly specific finding in ALS. In light of the above pathologic findings, we evaluated the liver function tests of 37 patients (including the above-mentioned 21 patients) with ALS, and found a high incidence of mild liver dysfunction. In spite of its subtleness, these ultrastructural changes of hepatocytes were consistently found in such patients, and offer further insight into the intrahepatic metabolic abnormalities in ALS.

Adult↗
PubMed1987

The effect of estriol on the production of alpha-fetoprotein by the liver in adult mice.

A single intraperitoneal injection with a 10 mg estriol (E3) in aqueous suspension induced a large and prolonged elevation of serum alpha-fetoprotein (AFP) in adult mice. E3 also raised the mitotic activity of hepatocytes in the absence of liver injury. Although both the AFP concentration and hepatocyte proliferation reached the peak on day 5 after E3 administration, a high level (about 12,500 ng/ml) of serum AFP persisted for a long period after hepatocyte proliferation declined. Five mg E3 showed a remarkable threshold effect on AFP elevation and 3 mg E3 on hepatocyte proliferation. Immunohistochemical studies indicated AFP production by hepatocytes in adult mice after the E3 administration.

Animals↗
PubMed1987

Comparison of antigenicity of serum immunoglobulin G among human, cynomolgus monkey, African green monkey and squirrel monkey.

Antigenicity of IgG was compared among human, the cynomolgus monkey, the African green monkey and the squirrel monkey by the quantitative precipitation test using purified IgG of and rabbit anti-IgG serum to each species. Clear cross-antigenicity was observed between the cynomolgus monkey and the African green monkey and less clear cross-antigenicity between human and the cynomolgus monkey or the African green monkey. The cross-antigenicity observed between the squirrel monkey and the other three species examined was evidently weak.

Animals↗
PubMed1987

Inhibitory effect of fumaric acid on hepatocarcinogenesis by thioacetamide in rats.

An inhibitory effect of fumaric acid (FA) on hepatocarcinogenesis was examined in rats fed thioacetamide (TAA). A group of male DONRYU rats were fed TAA at a level of 0.035% in the diet for 40 weeks and then fed a basal diet for 40 weeks. Hepatic carcinomas developed in 9 of 41 animals of this group fed TAA alone. The effect of FA on the carcinogenesis was examined in 2 groups fed both TAA and FA; one group of rats were fed FA at 1% in a basal diet after ingestion of TAA, and another group of rats were fed TAA plus a supplement of 1% FA in the diet. The inhibitory effect of FA on TAA carcinogenesis was so marked that no hepatic carcinomas were found in both groups fed FA in combination with TAA.

Acetamides↗
PubMed1986

Cross-linking of elongation factor 2 to rat-liver ribosomal proteins by 2-iminothiolane.

Complexes containing rat liver 80S ribosomes treated with puromycin and high concentrations of KCl, elongation factor 2 (EF-2) from pig liver, and guanosine 5'-[beta, gamma-methylene]triphosphate were prepared. Neighboring proteins in the complexes were cross-linked with the bifunctional reagent 2-iminothiolane. Proteins were extracted and then separated into 22 fractions by chromatography on carboxymethylcellulose of which seven fractions were used for further analyses. Each protein fraction was subjected to diagonal polyacrylamide/sodium dodecyl sulfate gel electrophoresis. Nine cross-linked protein pairs between EF-2 and ribosomal proteins were shifted from the line formed with monomeric proteins. The spots of ribosomal proteins cross-linked to EF-2 were cut out from the gel plate and labelled with 125I. The labelled protein was extracted from the gel and identified by three kinds of two-dimensional gel electrophoresis, followed by autoradiography. The following proteins of both large and small subunits were identified: L9, L12, L23, LA33 (acidic protein of Mr 33000), P2, S6 and S23/S24, and L3 and L4 in lower yields. The results are discussed in relation to the topographies of ribosomal proteins in large and small subunits. Furthermore we found new neighboring protein pairs in large subunits, LA33-L11 and LA33-L12.

Animals↗
PubMed1986

Histopathological studies on experimental marine toxin poisoning. I. Ultrastructural changes in the small intestine and liver of suckling mice induced by dinophysistoxin-1 and pectenotoxin-1.

Sequential ultrastructural changes were studied in mouse digestive organs after i.p. injections of dinophysistoxin-1 and pectenotoxin-1, causative agents of diarrhetic shellfish poisoning. Dinophysistoxin-1, a diarrheagenic substance, produced severe mucosal injuries in the small intestine within 1 hr after the administration of the toxin. The injuries were divided into 3 consecutive stages: extravasation of villi vessels, degeneration of absorptive epithelium and desquamation of the degenerated epithelium from the lamina propria. In contrast to dinophysistoxin-1, pectenotoxin-1, a non-diarrheagenic toxin from diarrhetic shellfish poisoning causative mussels, resulted in no abnormalities in the small intestine, but did cause characteristic liver injuries. Within 1 hr after the injection of pectenotoxin-1 numerous non-fatty vacuoles appeared in the hepatocytes around the periportal regions of the hepatic lobules. Electron microscopic observations with colloidal iron demonstrated that these vacuoles originated from invaginated plasma membranes of the hepatocytes.

Animals↗
PubMed1986

Damage to biological tissues induced by radical initiator 2,2'-azobis(2-amidinopropane) dihydrochloride and its inhibition by chain-breaking antioxidants.

A water-soluble azo compound, 2,2'-azobis(2-amidinopropane) dihydrochloride, a well-known free radical initiator, was administered intraperitoneally to mice to study the toxicological effects on biological tissues in vivo and their inhibition by chain-breaking antioxidants. It caused damage to biological tissues without biotransformation. No specific target organ was observed. The most striking fine structural changes were the degeneration, swelling, and disruption of the endothelium lining cells of the capillaries in various organs. Furthermore, the death of lymphocytes in the lymphoid tissues and the fatty degeneration of the liver and kidneys have also been observed. Water-soluble chain-breaking antioxidants, such as 2-carboxy-2,5,7,8-tetramethyl-6-chromanol (a vitamin E analogue), uric acid, cysteine, and glutathione suppressed the above damage, whereas vitamin C was ineffective.

Amidines↗
PubMed1986

Increased resistance to the anticellular effect of interferon in an ultraviolet light-resistant human cell line, UVr-1.

Interferon (alpha, beta and gamma) susceptibility was tested in a human cell line, UVr-1, a u.v. light-resistant variant of RSa cells; the latter have high sensitivity to both u.v. lethality and the cell proliferation inhibition (anticellular) effect of human interferon (HuIFN) preparations. UVr-1 cells were less sensitive than the parental RSa cells to the inhibitory effects of HuIFN preparations, as measured by cell proliferation and the incorporation of [3H]deoxythymidine and [3H]deoxyadenosine into acid-insoluble cellular material. Nevertheless, UVr-1 cells exposed to HuIFN showed almost the same enhanced levels of antiviral activity and pppA(2'p5'A)n synthetase activity as similarly treated RSa cells. Further, UVr-1 cells had much the same binding capacity for 125I-labelled HuIFN-alpha A. Thus, it seems likely that the variant has an increased resistance to the anticellular effect but not to the antiviral effect of HuIFN preparations. UVr-1 cells showed no significant difference from RSa cells in u.v.-induced DNA repair synthesis. However, when a comparison was made between the susceptibility of normal fibroblasts and fibroblasts from patients with Cockayne's syndrome, characterized by an altered u.v. sensitivity but no alteration of DNA repair replication synthesis, the Cockayne's syndrome fibroblasts, CCK-3 and CCK-4, were more susceptible to HuIFN-beta as judged by cell proliferation and deoxythymidine incorporation tests.

2',5'-Oligoadenylate Synthetase↗
PubMed1986

Fumaric acid enhances DNA synthesis of rat hepatocytes by counteracting the toxicities of mitomycin C and aflatoxin B1.

The effect of fumaric acid was examined on DNA synthesis in hepatocytes or hepatoma cells from rats treated with toxic agents. Male Donryu rats were injected with mitomycin C or aflatoxin B1, singly or in combination with fumaric acid. After a specified period, hepatocytes were isolated from the liver by the collagenase perfusion method and placed in culture, and their activities for DNA synthesis were measured. The iv injection of rats with mitomycin C (0.5 mg/kg) reduced the semiconservative DNA synthesis of the hepatocytes, but simultaneous dosing of fumaric acid (40 mg/kg) enhanced the recovery of the DNA synthesis. The DNA synthesis of hepatoma cells, a 3'-methyl-4-(dimethylamino)azobenzene-induced transplantable cell line growing in the abdominal ascites of rats, was also reduced by the iv injection of mitomycin C but, in contrast to that of the hepatocytes, was little influenced by the simultaneous dosing of fumaric acid. The ip injection of fumaric acid also reduced the toxicity of aflatoxin B1 (0.25 mg/kg, ip), preventing the reduction of DNA synthesis as well as the occurrence of nuclear degenerative changes in the aflatoxin B1-exposed hepatocytes.

Aflatoxin B1↗
PubMed1986

Postnatal changes of IgG and IgM levels in squirrel monkeys (Saimiri sciureus).

Serum IgG and IgM levels were measured in domestically bred squirrel monkeys (Saimiri sciureus) ranging in age from 0 days to 42 months, as well as in adult squirrel monkeys from the wild estimated to be 60 months or older. The results indicated that the transplacental transfer of IgG occurs in the squirrel monkey but the transferability is lower in the squirrel monkey than in the cynomolgus monkey. Immune response in the squirrel monkey occurs just after birth, as shown by IgM production.

Aging↗
PubMed1985

Neighboring proteins in rat liver 60 S ribosomal subunits disulfide-linked by hydrogen peroxide oxidation or cross-linked with dithiobis(succinimidyl propionate).

Neighboring proteins in rat liver 60 S ribosomal subunits were investigated by two kinds of cross-linking techniques: treatment of 60 S subunits with 1) hydrogen peroxide, which promotes the formation of protein-protein disulfide linkages and 2) a disulfide-bridged bifunctional reagent dithiobis(succinimidyl propionate). The cross-linked protein complexes formed were separated by two-dimensional polyacrylamide gel electrophoresis in a basic-sodium dodecyl sulfate gel system under nonreducing conditions. Each complex in the gel was labeled with 125I and extracted under reducing conditions. The protein components of the complex were analyzed by two kinds of two-dimensional polyacrylamide gel electrophoresis, followed by autoradiography. Closely neighboring pairs disulfide-linked by hydrogen peroxide were identified as L4-L6, L4-L29, L6-L29, L18a-L29, and L29-L32; more distant pairs cross-linked with dithiobis(succinimidyl propionate) were identified as L3-L5, L3-L24, L3-L37a, L4-L14, L4-L18a, L5-L10, L5-L11, L7/L7a-L27, L7/L7a-L36, L13-L35, and L13a-L14.

Animals↗
PubMed1985

Cross-linking study on protein topography of rat liver 60 S ribosomal subunits with 2-iminothiolane.

Rat liver 60 S ribosomal subunits were modified with 2-iminothiolane. After treatment with hydrogen peroxide, the cross-linked proteins were extracted and then separated into 24 fractions by chromatography on carboxymethylcellulose. Each protein fraction was then analyzed by diagonal polyacrylamide-sodium dodecyl sulfate gel electrophoresis (Sommer, A., and Traut, R.R. (1974) Proc. Natl. Acad. Sci. U. S. A. 71, 3946-3950). The pieces of gel containing cross-linked protein spots that were shifted from the diagonal line were labeled with 125I. The labeled protein was extracted from the gel and identified by three kinds of two-dimensional gel electrophoresis, followed by autoradiography. Fifty-three cross-linked protein pairs involving 35 protein species containing two acidic proteins were identified. From these and previous results, a preliminary model of the protein topography of the 60 S ribosomal subunit was constructed and discussed in relation to other functional data on 60 S ribosomal proteins.

Animals↗
PubMed1985

Effects of intra-arterially infused biodegradable microspheres containing mitomycin C.

We prepared biodegradable microspheres containing about 5% mitomycin C (MMC) and of 45 +/- 8 microns in diameter. These preparations were infused into the rat hepatic artery as a preclinical model of intra-arterial infusion treatment for patients with inoperable hepatic tumor. The leaked MMC levels in the hepatic vein decreased below the assay limitation 2 hours after conventional MMC injection, whereas in the case of MMC microsphere the leaked drug levels were maintained at almost the same concentration for over 2 hours after infusion. The entrapped period of MMC microspheres within the hepatic artery was at least 2 weeks, and the necrobiotic foci due to antitumor effects of the condensed MMC released from the microspheres were observed in the area fed by these entrapped arterioles. This phenomenon was never observed in the case of conventional MMC and placebo microspheres. Intra-arterial infusion of MMC microspheres may be a promising clinical treatment for patients with malignant hepatic tumor.

Animals↗