• Korean Journal of Veterinary Research
• /
• v.50 no.2
• /
• pp.93-103
• /
• 2010

This study investigated the potential effects of amitraz on the pre- and postnatal development, behavior, and reproductive performance of offspring of parent rats given amitraz during pre-mating, gestation, and lactation. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and lactation up to weaning. Based on fluid consumption, the male rats received an average of $0,\;5.7{\pm}1.33,\;13.2{\pm}2.08,$ and $35.8{\pm}3.42$ mg/kg/day amitraz, and the female rats received an average of $0,8.7{\pm}4.42,\;20.1{\pm}9.60,\;and\;47.6{\pm}22.38$ mg/kg/day amitraz, respectively. At 360 ppm, an increase in the incidence of abnormal clinical signs, a suppression in the body weight gain, a decrease in the food consumption and litter size, an increase in the post-implantation loss, and a decrease in the seminal vesicle weight were observed in the parent animals. In addition, a suppression in the body weight gain, a decrease in the grip strength, a delay in the negative geotaxis, an increase in the pre- and post-implantation loss, and a decrease in the number of live embryos were observed in the offspring. At 120 ppm, suppressed body weight gain and reduced food consumption were observed in the parent rats. Suppressed body weight gain and decreased grip strength were also observed in the offspring. There were no signs of either reproductive or developmental toxicity at 40 ppm. Under these experimental conditions, the no-observed-adverse-effect level of amitraz for parent rats and their offspring was estimated to be 40 ppm in rats.

• Journal of Chest Surgery
• /
• v.34 no.7
• /
• pp.515-523
• /
• 2001

Background: More than 70% of morbidity and mortality of diabetes mellitus is due to macrovascular complications. These complications may be associated with defect of endothelium-dependent vascular relaxation. There have been suggestions that this defect might be due to direct toxicities of oxygen-free radical. So in this study ascorbic acid was used as a dietary supplement in streptozotocin induced diabetic rats to correct this defect. Material and Method: Sixty male Sprague-Dawley rats were used in this study. They were divided into control and experimental groups. Streptozotocin was injected to the 33 rats of experimental group and then divided into two the other receiving subgroups; one receiving ascorbic acid supplement(1 g/l in drinking water); and nosupplements. At 6, 9 and 12 weeks, abdominal aortic rings were obtained to make tissue preparations for evaluation of vascular smooth muscle contractility. Result: While control group showed good response to acetylcholine induced relaxation, diabetic group showed decreased relaxation regardless of ascorbic acid supplement at the experiments 6 weeks after streptozotocin treatment. This abnormal endothelium-dependent vascular relaxation was markedly reversed at 9 and 12 weeks into the diabetic group with ascorbic acid supplement. There were no differences in sodium nitroprusside induced relaxation responses between control and experimental groups; also, norepinephrine induced contractile responses did not show any remarkable effects. Conclusion: These results strongly suggest that the endothelial cells have defects in diabetic rats. Dietary supplement of ascorbic acid can reverse the defects of diabetic endothelial cells through its antioxidant effects and it may further protect against vascular disease in diabetic patients.

• Journal of Food Hygiene and Safety
• /
• v.26 no.4
• /
• pp.388-397
• /
• 2011

Selenium (Se) is known to prevent from several cancers, while iron (Fe) is known to be associated with high risk of cancers. The role of Se on colon carcinogenesis was investigated in an animal model induced by azoxymethane (AOM) and dextran sodium sulfate (DSS) in low Fe mice. Six-week old ICR mice fed on a low Fe diet (4.5 ppm Fe; generally 10 times lower than normal Fe) with three different Se (0.02, 0.1 or 0.5 ppm) levels for 24 weeks. The animals received weekly three ($0{\sim}2^{nd}$ weeks) i.p. injections of AOM (10 mg/kg RW), followed by 2% DSS with drinking water for 1 week to induce the colon cancer. There were five experimental groups including vehicle, positive control (normal Fe level, AOM/DSS), Low Fe (LFe) + AOM/DSS+Low Se (LSe), LFe + AOM/DSS + medium Se (MSe) and LFe + AOM/DSS + high Se (HSe) groups. HSe group showed a 66.7% colonic tumor incidence, MSe group showed a 69.2% tumor incidence, and LSe group showed a 80.0% tumor incidence. The tumor incidence was negatively associated with Se levels of diets. Tumor multiplicity in Hse group was significantly low compared to the other groups (p < 0.05). With increasing Se levels of diets, the primary anti-proliferating cell nuclear antigen (PCNA)-positive cells were decreased and apoptotic bodies were increased in a dose-dependent manner. Se-dependent glutathione peroxidase activity and its protein level were dependent on the levels of Se of diets. Malondialdehyde level in liver was lowest in Hse group among experimental groups. These findings indicate that dietary Se is chemopreventive for colon cancer by increasing antioxidant activity and decreasing cell proliferation in Fe-deficient mice.

• Journal of Radiation Protection and Research
• /
• v.38 no.3
• /
• pp.138-142
• /
• 2013

This study was conducted to measure the uranium concentrations in urine of some members of the general public in Busan and Daejeon and to assess the annual committed effective doses from uranium analysis of daily excretion. As a result, the ranges of total uranium concentrations in the urine for the residents in Busan and Daejeon were found to be 0.556 - 1.53 $mBq\;L^{-1}$ and 2.18 - 4.55 $mBq\;L^{-1}$, respectively. It was noted that the uranium concentrations for the residents in Daejeon were observed to be higher than those for the residents in Busan. This result assumes that the uranium concentrations in the urines for the residents in Daejeon are probably related to the high uranium concentrations contained in the drinking water of Daejeon city. The bedrock of Daejeon, known as granitic rocks formed in the Jurassic period of the Mesozoic Era, contains high uranium contents. Also, results showed no significant correlation with age or sex. The ranges of annual committed effective doses from ingestion of uranium for the residents in Busan and Daejeon were calculated to be 0.472-1.41 ${\mu}Sv$ and 1.99-4.15 ${\mu}Sv$, respectively.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.15
• /
• pp.6363-6367
• /
• 2014

Purpose: This study was conducted to assess the preventive effect of Actinidia valvata Dunn (AVD) extract on an animal model of gastrointestinal carcinogenesis on the basis of changes in tumor incidence, cell proliferation, and apoptosis. Materials and Methods: Seventy-five male Wistar rats were divided into five different treatment groups with 15 rats in each group. Group I was given normal feed, whereas Groups II to IV were treated with 10% sodium chloride in the first six weeks and 100ug/mL of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in drinking water for 24 weeks. Group II was then given normal feed, whereas Group III was given AVD extract (0.24g/kg/day) for 12 weeks. Group IV was given AVD extract from the first week to the 36th week, whereas Group V was treated with AVD extract alone for 36 weeks. All rats were sacrificed at the end of the 36-week experiment and assessed for the presence of gastrointestinal tumors. The occurrence of cancer was evaluated by histology. Bax, Bcl-2, Caspase-3, and cyclinD1 were determined by immunohistochemical staining and Western blotting. Results: The incidences of gastric cancer were 0% in Group I, 73.3% in Group II, 33.3% in Group III, 26.7% in Group IV, and 0% in Group V. Bcl-2 and cyclinD1 expression was decreased in AVD extract treated groups, whereas Bax and Caspase-3 expression was increased. Comparison with group II revealed significant differences (p<0.01). Conclusions: AVD extract exhibits an obvious preventive effect on gastrointestinal carcinogenesis induced by MNNG in rats through the regulation of cell proliferation and apoptosis.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.5
• /
• pp.1983-1988
• /
• 2012

High temperature- and pressure-treated garlic (HTPG) has been shown to have enhanced antioxidative activity and polyphenol contents. Previously, we reported that HTPG inhibited 1,2-dimethylhydrazine-induced mucin depleted foci (premalignant lesions) and $O^6$-methylguanine DNA adduct formation in the rat colorectum. In the present study, we investigated the modifying effects of HTPG on N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG)-induced pyloric stomach and small intestinal carcinogenesis in mice. Male C57BL/6 mice were given ENNG (100 mg/l) in drinking water for the first 4 weeks, then a basal diet or diet containing 2% or 5% HTPG for 30 weeks. The incidence and multiplicity of pyloric stomach and small intestinal (duodenal and jejunal) tumors in the 2% HTPG group (but not in the 5% HTPG group) were significantly lower than those in the control group. Cell proliferation of normal-appearing duodenal mucosa was assessed by MIB-5 immunohistochemistry and shown to be significantly lower with 2% HTPG (but again not 5% HTPG) than in controls. These results in dicate that HTPG, at 2% in the diet, inhibited ENNG-induced pyloric stomach and small intestinal (especially duodenal) tumorigenesis in mice, associated with suppression of cell proliferation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.2
• /
• pp.195-201
• /
• 1995

In this study we wanted to investigate the effect of taurine supplement on the lipid peroxide formation and the activities of glutathione(GSH) dependent enzyme in diabetic model mice. We induce type I diabetes mellitus with alloxan injeciton in ICR mice and type II with high calorie diet in genetically hyperglycemic KK mice. Taurine was given in drinking water at the level of 5%(w/v) for seven days. In type I diabetic model, the malondialdehyde(MDA) of liver and islet significantly increased compared to control group and they significantly decreased by taurine supplement. In type II diabetic model, the concentration of MDA was not changed by taurine supplement. The activities of GSH-peroxidase(GPX) of liver and islet increased in type I diabetic group while decreased in type II. GPX activities were not changed by taurine supplement in the liver of both types but increased in the islet of type II. Taurine supplement has no effect on the activities of GSH S-transferase(GST) in both types. From these results, we suggest that taurine supplement protect against lipid peroxide formation in diabetic model of type I.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.7
• /
• pp.1052-1059
• /
• 2016

Red light (RL) marked higher weight gain (WG) and preference of broilers compared to other light colors. This study aimed to investigate how different intensities of RL affect the performance, behavior and welfare of broilers. RL treatments were T1 = high intensity (320 lux), T2 = medium intensity (20 lux); T3 = dim intensity (5 lux), T4 = control/white light at (20 lux) provided on 20L:4D schedule and T5 = negative control; 12 hours dark: 12 hours day light. Cobb strain broilers were used in a Complete Randomize Design with 6 replicates. WG, water/feed intake, feed conversion ratio (FCR), mortality, behavior and welfare were assessed. At 35 d, significantly (p<0.05) highest body weight ($2,147.06g{\pm}99$) was recorded by T3. Lowest body weight ($1,640.55g{\pm}56$) and FCR (1.34) were recorded by T5. Skin weight was the only carcass parameter showed a significant (p<0.05) influence giving the highest (56.2 g) and the lowest (12.6 g) values for T5 and T1 respectively. Reduced welfare status indicated by significantly (p<0.05) higher foot pad lesions, hock burns and breast blisters was found under T3, due to reduced expression of behavior. Highest walking ($2.08%{\pm}1%$) was performed under T1 in the evening during 29 to 35 days. Highest dust bathing ($3.01%{\pm}2%$) was performed in the morning during 22 to 28 days and highest bird interaction (BI) ($4.87%{\pm}4%$) was observed in the evening by T5 during 14 to 21 days. Light $intensity{\times}day$ $session{\times}age$ interaction was significantly (p<0.05) affected walking, dust bathing and BI. Light intensity significantly (p<0.05) affected certain behaviors such as lying, eating, drinking, standing, walking, preening while lying, wing/leg stretching, sleeping, dozing, BI, vocalization, idling. In conclusion, birds essentially required provision of light in the night for better performance. Exposed to 5 lux contributed to higher WG, potentially indicating compromised welfare status. Further researches are suggested to investigate RL intensity based lighting regimen that favors for both production and welfare of Broilers.

• The korean journal of orthodontics
• /
• v.30 no.6 s.83
• /
• pp.723-730
• /
• 2000

Orthodontic tooth movement requires remodelling of periodontal tissues, especially alveolar bone. Fluoride is known to be a potent inhibitor of osteoclastic bone resorption. The purpose of this study was to examine the effects of a consumption of fluoride on osteoclast numbers appearing on the pressure side of alveolar bones at experimental tooth movement. 40 male rats were exposed to 0, 10, 25 mg/kg/day of sodium fluoride(NaF) in their drinking water for up to 60 days. Orthodontic appliance were activated to mesially tip maxillary first molar with 50-70g. The rats were sacrificed at 1, 2, 4 days after initial activation. The number of osteoclast was counted in a $450\times700\;{\mu}m^2$ area interradicular septum on the pressure side of the maxillary first molar. The results were as fellows, 1. There was significantly different osteoclast number between control group and 25 mg/kg/day group at all measured time. (p<0.05) 2. There was significantly different active bone-resorption area between control group and 25 mg/kg/day group except at 96 hours post activation. (p<0.05) 3. There was slight reduction of active bone- resorption area in control group from 48 hours to 96 hours but in both 10 mg/kg/day group and 25 mg/kg/day group a slight increase was observed from 48 hours to 96 hours.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.2
• /
• pp.331-337
• /
• 2001

The effect of Phellinus linteus methanol extract on the lipid metabolism in the liver of rat was investigated in this study. Rats were randomly divided into 6 groups including the control, $CCl_4$and high fat group plus sub-groups with Phellinus linteus methanol extract administration. Methanol extracts of Phellinus linteus were fed 50mg/kg B.W daily via drinking water. A 1.2mL of $CCl_4/kg$ body weight was administered by oral intubation twice a week for total six times. The administration of $CCl_4$ increased total cholesterol, TG, LDL and LDL-phospholipid. However, the level of liver cholesterol and triglycerides were significantly decreased while HDL-cholesterol was increased by the extract feeding. The activities of GOT, GPT, AP and LDH were greatly enhanced by the extract feeding. Electronmicrograph showed that $CCl_4$ treatment deteriorated the structure of cytoplasmic matrix with its uneven distribution. However, the extract treatment reconstituted the damaged cytoplasm and stimulated mitochondriagenesis. From these results, it was suggested that Phellinus linteus can help to recover the damaged liver function and further may help to prevent senescence diseases such as fatty liver, hypertension and hyperlipidemia.