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C Sugiyama

Publications and source records attributed to C Sugiyama.

17 recordsLinked to original sources
PubMed2001

Shh and Ptc are associated with taste bud maintenance in the adult mouse.

In mammals, taste receptor cells are organized into taste buds on tongue. Taste buds are trophically maintained by taste neurons and under continuous renewal, even in adults. We found that the receptor for Sonic hedgehog (Shh), Patched1 (Ptc), was expressed around taste buds where cells were proliferating, and that Shh was expressed within basal cells of taste buds. Denervation caused the loss of Shh and Ptc expression before the degeneration of taste buds.

Animals↗
PubMed2001

Inhibition of DNA adduct formation and mutagenic action of 3-amino-1-methyl-5h-pyrido[4,3-b]indole by chlorophyllin-chitosan in rpsL transgenic mice.

We have studied the inhibitory effect of chlorophyllin-chitosan (Chl-Chi) complex, an insoluble form of chlorophyllin, on the DNA adduct formation and mutagenesis by a heterocyclic food mutagen-carcinogen, 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), in mice carrying the E. coli rpsL gene as a mutagenesis reporter. Upon administration of a diet containing 0.002% or 0.01% Trp-P-2, DNA adducts were formed in various tissues in a dose-dependent manner, with the maximum level observed in the liver. Addition of 3% Chl-Chi to the diet reduced the Trp-P-2 adduct by up to 90%. The rpsL mutant frequencies increased significantly in both the liver and spleen upon administration of a 0.01% Trp-P-2 diet. Addition of Chl-Chi to the diet decreased these induced mutant frequencies to the background level. No harmful effect of Chl-Chi was detected during these experiments. The results show that Chl-Chi may be a candidate chemopreventive agent against the genotoxic action of Trp-P-2, and possibly also other aromatic carcinogens in the diet.

Animals↗
PubMed2000

Induction of unscheduled DNA synthesis in hairless mouse epidermis by ultraviolet light.

The activity of ultraviolet (UV) light to induce unscheduled DNA synthesis (UDS) was investigated in hairless mouse epidermis by means of an in vivo-in vitro assay using a liquid scintillation counting method. Groups of three to five 8-week-old female hairless mice were irradiated with UV-B or UV-A, then skin samples were taken and cultured individually in medium containing [3H]thymidine with or without hydroxyurea (HU) for 2 hr. DNA of the epidermis was extracted, and incorporation of [3H]thymidine and the DNA content were determined with a liquid scintillation counter and a fluorescence spectrophotometer, respectively. Induction of UDS was judged in terms of the UDS index [(the ratio of DNA synthesis in the presence of HU to that in its absence) x 100]. UV-B increased the UDS index 1 hr after irradiation of 500 J/m2, which corresponds to approximately 1 minimal erythema dose or 1 minimal edema dose, and showed a dose-dependent increase up to 17-fold in the UDS index at irradiation doses of 500 to 2,000 J/m2. In a time-course study, UV-B also increased replicative DNA synthesis (RDS) 48 hr after irradiation at 1,000 J/m2. On the other hand, UV-A did not increase the UDS index at irradiation doses of 2 x 10(5) to 8 x 10(5) J/m2. These results show that induction of UDS by UV irradiation depends on wavelength and an increase of RDS in the epidermis exposed to UV-B irradiation appears after induction of UDS.

Animals↗
PubMed2000

Effect of aging on unscheduled DNA synthesis induction by UV-B irradiation in hairless mouse epidermis.

Age-related induction of unscheduled DNA synthesis (UDS) by ultraviolet B (UV-B) irradiation was investigated in the epidermis of female hairless mice by means of an in vivo--in vitro assay using a liquid scintillation counting method. Skin samples were taken and cultured in a medium containing [3H]thymidine with or without hydroxyurea (HU) for 2 hr. DNA of the epidermis was extracted, and the incorporation of [3H]thymidine into DNA and the DNA content were determined with a liquid scintillation counter and a fluorescence spectrophotometer, respectively. Induction of UDS by UV-B was judged in terms of the value of the UDS index calculated as a percentage of the respective unexposed control value taken as 100% [the UDS index is given by (the ratio of DNA synthesis in the presence of HU to that in its absence) x 100]. DNA synthesis both in the presence and absence of HU decreased with age [12 months old (M) < 8 M < 4 M < 2 M < 1 M)], concomitantly with a small but significant increase of UDS index. The decrease was high in the younger age groups and moderate in the older age groups. UV-B increased the UDS index approximately 14-, 12- and 9-fold at 1 hr after 1,000 J/m2 irradiation in 1 M, 2 M and 12 M mice, respectively, and these increases were partly reversed at 4 hr after irradiation. UV-B also increased the UDS index approximately 25-, 24- and 21-fold at 1 hr after 4,000 J/m2 irradiation for each age group. However, there was no statistically significant age-related difference in the magnitude of the UDS index after irradiation of UV-B. These results show that replicative DNA synthesis decreases with age, whereas DNA repair capacity after UV-B irradiation does not change with age under these conditions.

Aging↗
PubMed1999

Porphyrins as possible preventers of heterocyclic amine carcinogenesis.

Our studies have shown that hemin and chlorophyllin can directly interact with heterocyclic amines (HAs) and prevent their mutagenic actions. Hemin and chlorophyllin can trap HAs efficiently, probably by forming face-to-face complexes with them. The trapping was most clearly demonstrated by use of solid-supported porphyrins, hemin-agarose and chlorophyllin-chitosan. Furthermore, spectroscopic measurements have suggested that there are interactions in solution between the porphyrins and the HAs. A number of in vivo data have been accumulated by efforts from many laboratories for the anticarcinogenic and antigenotoxic properties of porphyrins, particularly chlorophyllin, against HAs.

Animals↗
PubMed1999

Inhibitory effects of beer and other alcoholic beverages on mutagenesis and DNA adduct formation induced by several carcinogens.

The possibility that beer and other alcoholic beverages could be antimutagenic against the heterocyclic amines (HAs), a group of carcinogens produced on cooking proteinaceous foods, has been explored. In the Salmonella mutation assays, beer showed inhibitory effects against several HAs [preactivated Trp-P-1, Trp-P-2(NHOH), and Glu-P-1(NHOH)] that are directly mutagenic in bacteria. Japanese sake, red and white wines, and brandy were also effective. However, ethyl alcohol alone did not show these effects. The formation of O(6)-methylguanine by N-methyl-N'-nitro-N-nitrosoguanidine in the DNA of Salmonella YG7108 was also inhibited by beer. Nonvolatile beer components were administered orally to CDF(1) mice together with Trp-P-2. Adducts in the liver DNA were significantly decreased by the beer, as compared to those in controls fed Trp-P-2 only. Although several phenolic compounds known to be present in beer were antimutagenic toward these mutagens, their effects were very small. It was concluded that some yet to be identified component(s) of beer is (are) responsible for this antimutagenicity.

Alcoholic Beverages↗
PubMed1999

A linkage map of 243 DNA markers in an intercross of Göttingen miniature and Meishan pigs.

A resource family of pigs has been constructed by using a boar of Göttingen miniature pig and two sows of Meishan pig as parents. In the construction of the family, two F1 males and 18 F1 females were intercrossed to generate 143 F2 offspring. The members of the family were genotyped using 243 genetic markers including 26 markers developed in our laboratory in order to generate a linkage map of markers for use in detecting quantitative trait loci (QTLs) in the family. The markers consisted of 237 microsatellites, five PRE-1 markers, and one RFLP marker. The linkage map was revealed to cover all 18 autosomes and the X chromosome; and the total length of the sex-averaged linkage map was calculated to be 2561.9 CM. Four out of the 26 markers developed in our laboratory exended the current linkage map at the termini of chromosomes 1p, 5p, 11p, and Xq. The linkage maps of all the chromosomes except for chromosome 1 were found to be longer in females than in males. Concerning chromosome 1, the length of the linkage map showed no difference between females and males, which was attributed to low recombination rates between markers localized in the centromeric region in females. The average ratio of female-to-male recombination was calculated to be 1.55.

Animals↗
PubMed1999

Induction of unscheduled DNA synthesis in hairless mouse epidermis by skin carcinogens.

Induction of unscheduled DNA synthesis (UDS) in hairless mouse epidermis by six chemicals was determined in an in vivo-in vitro assay by using a liquid scintillation counting method. Test chemicals were applied once onto two areas of the back of female hairless mice after stripping of the stratum corneum with adhesive tape to enhance skin penetration. After exposure, the skin samples were taken and cultured in a medium containing [3H]thymidine with or without hydroxyurea (HU, an inhibitor of replicative DNA synthesis). DNA of the epidermis was extracted, and incorporation of [3H]thymidine into DNA and the DNA content was determined with a liquid scintillation counter and a fluorescence spectrophotometer, respectively. Induction of UDS by chemicals was judged by calculation of the UDS index [(the ratio of DNA synthesis in the presence of HU to that in its absence) x 100]. A good correlation between UDS induction and organ specificity of carcinogens was observed. 4-Nitroquinoline 1-oxide, a skin carcinogen used as a positive control, induced a dose-dependent increase in the UDS index of approximately 12-fold at 2 hr after exposure, while 1,2-epoxydodecane, a non-skin carcinogen applied as a negative control, did not increase the UDS index. Four other skin carcinogens induced dose-dependent increases in the UDS index; N-methyl-N'-nitro-N-nitrosoguanidine and diepoxybutane at 2 hr after exposure, and 7,12-dimethylbenz[a]anthracene and benzo[a]pyrene at 24 hr after exposure. The results suggest that UDS is a good marker of the genotoxicity of skin carcinogens.

4-Nitroquinoline-1-oxide↗
PubMed1999

Nutrient intakes in relation to style of breakfast and taste preferences.

Style of breakfast (western- or Japanese-style) and taste preferences were associated with various diseases in some epidemiological studies in Japan. To evaluate what are measured by asking these dietary behaviors, we administered semiquantitative food frequency questionnaire (SFFQ) and asked style of breakfast and taste preferences to a subsample of residents in Takayama City, Gifu, Japan. Style of breakfast and total diet were studied in a random sample of 346 residents. There were no statistically significant differences in the nutrient intakes estimated from SFFQ between those with western- and Japanese-style of breakfast except for crude fiber. Taste preferences were asked to 555 men and 1,130 women who attended a health check-up program in the community. Salt intakes were slightly higher (< 3%) in those who had a favor for salty food than the others in both sexes. Fat or carbohydrate intake was similar between those stratified by preference for greasy or sweet foods. The data suggest that western-style of breakfast is not associated with western diet, in general, i.e., high-calorie and high-fat diet. Intakes of salt, fat, or carbohydrate appear to be unrelated to preferences for salty, greasy or sweet foods, respectively.

Adult↗
PubMed1998

Role of cardiac troponin I in the evaluation of myocardial injury.

Cardiac troponin I (cTnl) is highly specific for cardiac muscle. In this study, we compared the utility of CK and CK-MB index versus cTnl in the assessment of myocardial infarction in 155 patients being evaluated for myocardial damage. As a cardiac marker for MI, Troponin I seems to be superior to CK-MB. In the subset of patients with renal disease, cTnl has definite advantages over CK-MB. In addition, the use of cTnl has the potential to replace the measurement of lactate dehydrogenase isoenzymes.

Biomarkers↗
PubMed1996

Inhibition of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline-mediated DNA-adduct formation by chlorophyllin in Drosophila.

The effect of chlorophyllin on 2-amino-3,8-dimethyimidazo[4,5-f]quinoxaline (MeIQx)-mediated DNA-adduct formation in Drosophila was studied. Third-instar larvae of Drosophila were fed MeIQx at 1 mg/6.5 g-feed/bottle, with or without chlorophyllin (100-300 mg). After a 6 h feeding exposure to MeIQx, the larvae were divided into 2 groups. The first group was examined for covalent DNA adducts by 32P-postlabeling assay. The second group was assayed for DNA damage by allowing the larvae to develop to adults and measuring the male/female ratio (males, DNA repair-deficient; females, DNA repair-proficient). The 32 P-postlabeling results indicated a significant decrease in DNA adduct levels in larvae treated with MeIQx and 300 mg chlorophyllin (1.7 +/- 0.7 adducts/10(7) nucleotides) as compared with MeIQx-treated larvae 6.5 +/- 2.1 adducts/10(7) nucleotides). The results on male/female sex ratios also indicated a chlorophyllin-induced decrease in DNA damage by exposure to MeIQx. The suppressive effect of chlorophyllin on the genotoxic actions of a polycyclic mutagen, MeIQx, may be a result of complex formation between chlorophyllin and the mutagen.

Animals↗
PubMed1996

Prostate-specific antigen concentrations in serum in acute illnesses.

In light of recent studies showing that prostate-specific antigen (PSA) complexes with certain blood proteins, we studied the effects of acute-phase reactants and alpha 2-macroglobulin (A2MG) on serum concentrations of PSA. Serum samples were obtained from 419 men admitted to an acute-care facility. Various acute-phase reactants-including C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antitrypsin, and alpha 1-antichymotrypsin-and A2MG were measured with a Beckman Array analyzer in parallel with determinations of PSA concentrations by two methods, the Hybritech Tandem RIA and the Abbott PSA IMx. Evaluation by Spearman rank correlation revealed a significant negative correlation of A2MG with PSA values (P < 0.01) and (as expected) a positive correlation of age with PSA values (P < 0.001). The former correlation suggests the possibility that patients with high serum concentrations of A2MG may give falsely decreased results for PSA concentrations in serum.

Acute Disease↗
PubMed1993

Increasing effect of tri-n-butyltins and triphenyltins on the frequency of chemically induced chromosome aberrations in cultured Chinese hamster cells.

Organotins have been widely used as anti-fouling coatings for fishing nets and ship bottoms, and marine pollution by them has become a serious environmental problem. In this communication, the potentiating effects of three kinds of tri-n-butyltins and three thiphenyltins on chromosome aberrations were studied in Chinese hamster CHO K1 cells. None of the organotins studied showed any clastogenic activity under the experimental conditions without rat liver S9. Post-treatment with organotins, however, increased the number of breakage-type (but not exchange-type) chromatid aberrations induced by five kinds of S-phase-dependent clastogens: MMC, cisPt, 4NQO, MMS, and AMD). Enhancement of the induction of chromosome aberrations by MMC was observed when cells were treated with organotins during the G2 phase. These results suggest that organotin G2 effect causes potentiating effects. Organotins also enhanced the induction of breakage-type chromatid aberrations by clastogenic pollutants in chlorinated tap water, indicating their potential for a more realistic health risk.

Animals↗
PubMed1989

Micronucleus test with 2-acetylaminofluorene by intraperitoneal injection and oral administration.

The effect of route of administration on the outcome of the mouse micronucleus test was evaluated in 2 laboratories by administering 2-acetylaminofluorene (2-AAF) by intraperitoneal injection (i.p.) and oral gavage (p.o.) to 2 mouse strains, MS/Ae and CD-1. On the basis of a small-scale acute toxicity study and a pilot micronucleus test, the full-scale experiment was performed with a 24-h sampling time at doses ranging from 75 to 600 mg/kg by both routes. The results indicated that 2-AAF induced micronucleated polychromatic erythrocytes (MNPCEs) at all doses tested by both routes. In the MS/Ae strain, higher doses were required by p.o. than by i.p. to reach a similar level of MNPCE incidence. On the other hand, similar responses were recorded by both administration routes with CD-1 mice. Since the LD50 for the p.o. route was higher than that for the i.p. route in both strains, the route-related difference with MS/Ae mice became small when the comparison between i.p. and p.o. was made on the basis of the LD50. Thus both i.p. and p.o. routes are acceptable in the micronucleus test of this chemical.

2-Acetylaminofluorene↗
PubMedDate not supplied

The micronucleus test of methyl methanesulfonate with mouse peripheral blood reticulocytes using acridine orange-coated slides.

The usefulness of the micronucleus assay using mouse peripheral blood erythrocytes and acridine orange (AO)-coated slides was evaluated with methyl methanesulfonate (MMS). The micronucleus test was carried out at doses ranging from 20 to 80 mg/kg body weight in CD-1 mice by intraperitoneal injection. Peripheral blood cells were examined from 0 to 72 h after treatment at 12- or 24-h intervals. Bone marrow cells from other mice treated with 80 mg/kg MMS were also sampled at the same times. The frequency of micronucleated reticulocytes (MNRETs) increased dose-dependently at every sampling time except 72 h, and the maximum frequency of MNRETs was observed at about 36 h after treatment. Micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow after a dose of 80 mg/kg were significantly induced at 12 h to 36 h, and the maximum frequency of MNPCEs was observed at 24 h after treatment. The induction of MNRETs was delayed by about 12 h compared to that of MNPCEs in bone marrow, and the maximum frequencies of MNRETs were lower than those of MNPCEs, but the induction of MNRETs by MMS was significant and dose-dependent. It is concluded, therefore, that bone marrow cells could be replaced by peripheral blood cells as material for the micronucleus assay using AO-coated slides.

Acridine Orange↗