• Food Science and Biotechnology
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• v.15 no.6
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• pp.980-985
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• 2006

The goal of this study was to investigate the effects of a newly developed functional food containing Bacillus polyfermenticus (BP) and other physiologically active materials on the antioxidant system and the process of colon carcinogenesis in male F344 rats. Following a one-week adaptation period, the rats were divided into 3 groups and fed either a high-fat, low-fiber diet (control and DMH groups), or a high-fat, low-fiber diet supplemented with B. polyfermenticus ($3.1{\times}10^8\;CFU/day$) and other physiologically active materials (chitosan, chicory, ${\alpha}$-tocopherol, and flavonoids) (DMH+BP group). One week after the initiation of the diets, 2 groups of rats were subjected to six weeks of treatment with 1,2-dimethylhydrazine (DMH, 180 mg/kg BW, s.c.). The dietary treatments remained consistent throughout the entire experimental period. Nine weeks after the initial DMH injection, the rats supplemented with B. polyfermenticus had significantly lower numbers of aberrant crypt foci than those in the DMH group. Injections with DMH resulted in significantly higher leukocytic DNA damage and plasma lipid peroxidation levels, as well as in a lower plasma total antioxidant potential. These effects were reversed following supplementation with B. polyfermenticus and other physiological materials. Our results indicate that a functional food containing B. polyfermenticus exerts a protective effect on the antioxidant system and on the process of colon carcinogenesis, thereby suppressing the development of preneoplastic lesions.

• Toxicological Research
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• v.7 no.1
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• pp.83-92
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• 1991

Complexities of testis structure and function are emphasized in morphometrical and genotoxic evaluation by statistical analysis. F-344 rats were treated with azinphos methyl, cyclophosphomide, and dichlorvos. And Brdu was injected with intrapertionially before sacrifice. The existence and degree of DNA damage were measured by Brdu labeling index which represented relative amount of Brdu incorporated in DNA, morphometric change was evaluated by the relative length of tubular diameter in circular seminiferous tubules and the number of spermatogonia per Sertoli cell in stage IX seminiferous tubules.

• Toxicological Research
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• v.9 no.2
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• pp.241-251
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• 1993

Present studies were carried out in order to estabilish the bronchoalveolar lavage method and to examine the response of bleomycin and peplomycin on the total cell number and the subpoulations of bronchoalveolar lavage fluid. A total of 24 male F344 rats, weighing 300-350 mg, were divided into 3 groups. Animals recelved either belomycin (BLM` 0.75 mg/0.2 ml/rat), peplomycin (PLM` 0.25mg/0.2ml/rat) for groups 2 and 3 or an equal volume of sterile saline lacking drugs for controls (group 1).

• Environmental Mutagens and Carcinogens
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• v.19 no.2
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• pp.89-94
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• 1999

Cell proliferation and c-Jun expression pattern in liver exposed by nongenotoxic carcinogens phenobarbital (PB) and clofibrate, and genotoxic carcinogen 2-amino-3-methylimidazo [4,5-f] quinoline (IQ) were investigated to see whether differential effects of genotoxic and non-genotoxic carcinogens on the development of neoplastic foci may be related to differential effect on cell proliferation. Male F344 rats were initially given a single intraperitioneal injection of diethylnitrosamine (200 mg/kg body weight), and 2 weeks later, animals were fed diets containing 0.03% IQ or 0.5% CE or 0.05% PB or basal diet as a control for 6 weeks. All rats were subjected to the two-thirds partial hepatectomy (PH) at week 3. Sequential sacrifice of rats was performed until 8 weeks. Cell proliferation was examined by immunohistochemical staining of bromodeoxyuridine and c-Jun expression was determined by northern blotting. The increase of cell proliferation rate after PH was significant in the rats fed 0.05% IQ and continued until 8 weeks, while the increase was not significant in the rats fed phenobarbital and clofibrate compared to that in the rats fed control diet. mRNA level of c-Jun in the liver treated with IQ was about 7 fold higher than that of control and peak at 5 hours after rH. In the liver treated with CE, mRNA level of c-Jun was 3-4 fold higher than that of control and the highest level of mRNA of c-Jun was seen at 24 hours after PH. These results show that differential effects of genotoxic and non-genotoxic carcinogens on the development of neoplastic foci may be related to differential effect on cell proliferation pattern.

• Journal of Life Science
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• v.10 no.1
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• pp.22-36
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• 2000

The mammary gland contains a subpopulation of epithelial cells with large proliferative potentials which are the likely targets for carcinogens. These clonogenic cells can proliferate and differentiate into functional glandular structures. Multicellular secretory alveolar units (AU) develop from these clonogens in grafts of monodispersed rat mammary epithelial cells (RMEC) in gland-free mammary fat pads in intact recipient F344 rats co-grafted with mammotropic hormone-secreting pituitary tumors (MtT F4). Multicellular nonsecretory ductal units (DU) develop in grafts of monodispersed RMEC in gland-free fat pads in adrenalectomized recipient WF rats co-grafted with MtT W10. However, this effect were reversed by hydrocortisone replacement therapy. RMEC were isolated from appropriate donor rats as monodispersed mixed cells or, alternatively, RNA＋ cells were sorted by flow cytometry of mixed RMEC stained with FITC-RNA and PE-anti-Thy-1.1 monoclonal antibody. We grafted mixed or sorted PNA+ cells in gland-free mammary fat pads in recipient rats that were endocrinologically manipulated to induce AU or DU. Cells were also isolated from these AU or DU as mixed or sorted RNA＋ cells and sub-transplanted in recipient rats treated appropriately to induce AU or DU, respectively. Cells obtained from AU in grafts gave rise to clonal AU and from DU in grafts to DU on sub-transplantation in appropriate recipients. When adrenalectomized recipient WF rats co-grafted with MtT W10 received daily subcutaneous injections of hydrocortisone for periods of 21 days following the PHA＋ cell transplantation, AU, instead of DU, were developed. The histologies of these secondary AU and DU were not different from those of the primary AU and DU. Casein and laminin proteins were demonstrated by immunocytochemical staining of primary and secondary AU. Electron micrographs also demonstrated that AU were composed of secretory cells with milk protein in the cytoplasm. DU were composed of little or non-secretory ductal epithelial cells. These AU and DU also secreted large amounts of lipids. Clonogenic cells were more common in DU than in AU. Thus, AU and DU contain persistent subpopulations of clonogenic stem-like cells.

• Journal of Food Hygiene and Safety
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• v.5 no.4
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• pp.179-186
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• 1990

This study was performed for assessing carcinogenicity of several synthetic hormones; Diethylstilbesterol (DES), 17-ethinylestradiol ($EE_2$) and Bovine somatotrophin (BST). Six weeks old F344 rats were divided into five groups and given an intraperitoneally injection of 200 mg of diethylnitrosamine (DENA). At two week after beginnig of experiment, DES, $EE_2$, BST. Phenobarbital were administered to group 1, 2, 3 and 4 respectively, group 4 is positive control and group 5 is negative control. At the same time, all groups received a single i.p. injection of D-galactosamine at a dose of 300 mg/kg and underwent 2/3 partial hepatectomy at week 5. All rats were sacrificed at the end of week 8 for assessment of liver lesion development. The liver was processed for immunohistochmical staining for GST-P and quantitatively analyzed by image analyzer. It was concluded that two synthetic estrogen hormones (DES, $EE_2$) was different significantly (p < 0.01) but BST was not different as compared with control group. Therefore, we thought that DES, $EE_2$ was promoting effects and BST was not in rat hepatocarcinogenesis.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.157-165
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• 2008

Cancer-preventive effects of ethanol extract of elm tree root (EEE) were investigated. In the in vitro cytotoxicity assay, colon cancer cells were incubated with a chloroform fraction of EEE (CF-EEE). CF-EEE significantly inhibited the proliferation of cells and induced apoptotic cell death in a dose-dependent manner. For the assessment of chemopreventive efficacy in vivo, male F344 rats were fed with EEE (0.5 or 1%) in diet for 8 weeks, and were subcutaneously injected with 1,2-dimethylhydrazine (DMH) to induce colonic aberrant crypt foci (ACF). EEE (0.5 and 1%) significantly decreased both the numbers of AC (1191.1/colon) and ACF (529.3/colon) induced by DMH. In addition, in the Western blot analysis on the colonic mucosa, administration of EEE triggered expression of caspase-3, a key factor of an apoptotic cascade. These results suggest that extract of elm tree root may have potential chemopreventive principles that lead to apoptosis of cancer cells, and thereby suppress colorectal carcinogenesis during the initiation stage.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.859-866
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• 2007

The main objective of this study was to investigate the effects of exercise on serum insulin and leptin levels and GLUT-4 and VAMP-2 in skeletal muscles from the pregnant rats. F344 rats were randomly divided into four groups (n = 15 in each group): control group (CG), pregnant group (PG), pregnant running group (PR), and pregnant swimming group (PS). From the 15th day of pregnancy, animals in the running group were forced to run on treadmill for 30 min with a light intensity, while those in the swimming group were forced to swim in swimming pool for 10 min once a day for 6 consecutive days. The present result demonstrated that in pregnant rat group, serum insulin levels significantly in-creased and leptin levels significantly decreased. Skeletal GLUT-4 and VAMP-2 protein expression was significantly decreased in pregnant rats compared to non-pregnant rats. However, matenal running during gestational period alleviated pregnancy-induced changes in plasma insulin and leptin levels, and it significantly enhanced skeletal GLUT-4 and VAMP-2 protein expression. From those results, it can be suggested that running exercise during gestational period may improve glycemic control by up-regulating GLUT-4 and VAMP-2 protein expression.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.63-67
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• 2003

Mercury, one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. Although the reports indicate that the mercury induces a deleterious damage, little has been known from the investigations of its effects in living organisms. The purpose of this study is to evaluate the effects of mercury chloride and ionizing radiation. Prepubertal male F344 rats were administered mercury chloride in drinking water throughout the experimental period. Two weeks after whole body irradiation, organs were collected to analyze the induced injury. Serum levels of GOT, GPT, ALP, and LDH were checked in the experimental groups and the hematological analysis was accomplished in plasma. In conclusion, the target organ of mercury chloride seems to be urinary organs and the pattern of damage induced by mercury differs from that by irradiation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.3
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• pp.224-234
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• 2007

This study aimed to examine the harmful effects of Mn and Fe, which may be generated as dust or fume in the industrial sites, on the body and genital organs by their inhalation. It is intended to find the characteristics and differences of the hazardousness by inhaling a single and the mixed materials of Mn and Fe. Male F344 rats were divided into the control group and 3 exposed groups on the basis of the test material compound (Mn $1.5mg/m^3$, Mn 1.5 and Fe $3.0mg/m^3$, Fe $3.0mg/m^3$). The 4 groups were divided into 4 subgroups again on the basis of the exposure period (4 and 13 weeks) and the recovery period (4 and 13 weeks). The exposure condition was 6 hours a day, 5 days a week for the whole body. Clinical tests including changes in weight and feed rate, blood biochemical test, motility change, changes in the number and the amount of spermatozoon (sperm count), daily sperm production (DSP), deformity test of spermatozoon and changes in the accumulation of Mn and Fe in blood and internal organs were performed. Motility was reduced by Mn exposure. Especially, the effect of Mn was exposure period responsible. By mixing with Fe, no significant change in motility Mn and Fe accumulation in organs was observed. Sperm count and daily sperm production (DSP) were decreased by Mn. Additional effect like the reduction of sperm count and DSP, and delayed restoration of sperm count and DSP during the recovery period were observed in the mixed exposure group. These results indicate that Mn and Fe may affect the motility reduced and has male reproductive toxicity. Mixed exposure of Mn and Fe lead to synergic effects on the male reproductive toxicity.