• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.734-740
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• 2010

Overuse of veterinary antibiotics threats public health and surrounding environment due to the occurrence of antibiotic resistant bacteria. The objective of this study was to evaluate the antibiotic's concentrations of tetracycline (TC), chlortetracycline (CTC), and oxytetracycline (OTC) in a tetracycline group (TCs), sulfamethazine (SMT), sulfamethoxazole (SMX), and sulfathiazole (STZ) in a sulfonamide group, lasalocid (LSL), monensin (MNS), and salinomycin (SLM) in a ionophore (IPs), and tylosin (TYL) in a macrolide (MLs) group from soil, water, and sediment samples adjacent to a cattle manure composting facility. For all samples of soil, water, and sediment, the highest concentrations were detected in TCs among the tested antibiotics because of its higher annual consumption in veterinary farms, Korea and its higher cohesiveness with divalent or trivalent cations in soil. Moreover, the concentrations of residual antibiotics in September were generally higher than in June because of heavier rainfall in June. We suggest that continual monitoring and developing guideline of antibiotics are needed to control residual antibiotics in the environment.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.8-13
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• 2000

A study was carried out to determine the probiotic effect of Lactobacillus reuteri BSA-131 by investigating the growth performance and fecal microbial population of piglets. Five dietary treatment groups, the basal diet (control, BD), basal diet with antibiotics(BA), basal diet with 2$\times$106/g of probiotics (BP6), 2$\times$108/g of probiotics (BP8) and basal diet with antibiotics and 2$\times$108/g probiot-ics(BAP8) were divised. Each dietary treatment group was consisted of 1 month of age piglets(male 13, female 12). Fecal micro-flora, body weights and feed consumption were measured at before, after and stop feeding of probiotics. The results showed that the CFU of fecal Enterobacteriaceae of piglets of the group BA, BP6, BP8 and BAP8, were reduced (P<0.05) compared to control BA. On the contrary, Lactobacillus counts were increased significan시 (P<0.001) in all groups fed probiotics dites, but not antibiotics. Body weight of probiotics treated piglets were improved 5% (p<0.001) in BP6 group than that of control group and antibiotic treated piglets BAP group was 27% (P<0.001) higher than BA group. The amount of feed consumption value of probiotics treated piglets showed 21-30% (P<0.001) lower intake than the control group, whereas antibiotic treated piglets BAP was 20% (P<0.001) higher than BA group. The results showed that body weights and feed to gain ratios were improves 19% when compared to control piglets for groups fed diets probiotic. It is very suggestive that productivity of probiotic piglets would be economical in pig farming.

• Toxicological Research
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• v.18 no.2
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• pp.195-203
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• 2002

This study was performed to evaluate single and repeated-dose toxicities oj a new cophalosporin antibiotic agent IDC-7l81 in Sprague-Dawley rats. IDC-7181 was injected intravenously to rats at dose levels of 0, 3.2, 16, 80, 400 and 2,000 mg/kg/day for single-dose toxicity study and at dose levels of 0, 10, 50 and 250 mg/kg/day for 4-week repeated-dose toxicity study. In both studies, there were no dose-related changes in mortality clinical signs, body weight changes, food and water consumption, opthalmoscopy, organ weights, urine analysis, biochemical examination, and hematological findings of all animals treated with IDC-7l8l. Gross and histopathological findings revealed no evidence of specific toxicity related to IDC-7181. These results suggest that the intravenous maximum tolerated dose value of IDC-7181 may be over 250 mg/kg and $LD_{50}$ value may be over 2,000 mg/kg in rats.

• Biomolecules & Therapeutics
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• v.2 no.1
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• pp.94-101
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• 1994

DA-125, a new anthracycline antitumor antibiotic, was at dose levels of 0, 0.03, 0.1 and 0.3 mg/kg/day administered intravenously to Sprague-Dawley male rats from premating to mating period and to females from premating to early gestation period. Effects of test agent on general findings and reproductive performance of parent animals and embryonic development were examined. No treatment-related changes in clinical signs, body weight, food consumption and necropsy findings were observed in all groups of both sexes. At 0.3 mg/kg, a decrease in the weight of spleen was found only in male rats. Mating performance and fertility of parent animals were not adversely affected by all doses tested. Fl fetuses showed no changes related to treatment of DA-125, except that at 0.3 mg/kg, an increase in the resorption rate was seen. The results show that the no effect dose levels (NOELS) for general toxicity of parent animals and fetal development are 0.1 mg/kg/day and NOELS for reproductive capability are over 0.3 mg/kg/day.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.51-58
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• 1996

A new composite antibiotic, SM-101(sulbactam.metampicillin), was at dose levels of 0, 250, 500 and 1000 mg/kg/day administered intravenously to Sprague-Dawley male rats from predating to mating period and to females from premating to early gestation period. Effects of test agent on general findings and reproductive performance of parent animals and embryonic development were examined. In male parents, two deaths occurred at 1000 mg/kg. The increase in kidney weight of the 1000 mg/kg group were also observed. The decrease in body weight and food consumption were found at 500 and 1000 mg/kg. The decrease in spleen weight were seen at 250, 500 and 1000 mg/kg. In female parents, three deaths were found at 1000 mg/kg. Mating performance and fertility of parent animals were not adversely affected by all doses tested. F1 fetuses showed no changes related to treatment of SM-101. The results show that the no effect dose level(NOEL) for general toxicity of parent animals is under 250 mg/kg/day and NOELS for reproductive capability and fatal development are over 1000 mg/kg/day.

• Biomolecules & Therapeutics
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• v.2 no.1
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• pp.82-93
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• 1994

DA-125, a new anthracycline antitumor antibiotic, was at dose levels of 0, 0.1, 0.3 and 1.0 mg/kg/day administered intravenously to pregnant Sprague-Dawley rats during the organogenetic period. Two-third of dams per group were subjected to caesarean section on day 20 of pregnancy and the remaining 10 dams per group were allowed to deliver. Effects of test substance on dams, embryonal development of Fl fetuses, as well as growth, behaviour and mating performance of Fl offspring were examined. 1. At 1 mg/kg, one out of the 10 dams showed difficult delivery. A decrease in food consumption, a loss in body weight and a decrease of spleen weight were found in this dose level group. At 0.3 mg/kg, difficult deliverys were observed in two out of the 10 dams. 2. At 1 mg/kg, an increased resorption rate and a decreased fetal weight were found. In addition, various types of external, visceral and skeletal malformations occurred at an incidence of 11.9, 41.8 and 14.5%, respectively. 3. At 1 mg/kg, body weight reduction, small eyeball, hydrocephalus and atrophy of sexual organs were observed in Fl offspring. One male pup receiving 0.3 mg/kg died on day 2 of lactation. The results show that the no-effect dose levels (NOELs) for dams and Fl offspring are 0.1 mg/kg/day and NOEL for Fl fetuses is 0.3 mg/kg/day.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.275-280
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• 2002

In order to control glucose concentration during fed-batch culture for antibiotic production, we applied so called “software sensor” which estimates unmeasured variable of interest from measured process variables using software. All data for analysis were collected from industrial scale cultures in a pharmaceutical company. First, we constructed an estimation model for glucose feed rate to keep glucose concentration at target value. In actual fed-batch culture, glucose concentration was kept at relatively high and measured once a day, and the glucose feed rate until the next measurement time was determined by an expert worker based on the actual consumption rate. Fuzzy neural network (FNN) was applied to construct the estimation model. From the simulation results using this model, the average error for glucose concentration was 0.88 g/L. The FNN model was also applied for a special culture to keep glucose concentration at low level. Selecting the optimal input variables, it was possible to simulate the culture with a low glucose concentration from the data sets of relatively high glucose concentration. Next, a simulation model to estimate time course of glucose concentration during one day was constructed using the on-line measurable process variables, since glucose concentration was only measured off-line once a day. Here, the recursive fuzzy neural network (RFNN) was applied for the simulation model. As the result of the simulation, average error of RFNN model was 0.91 g/L and this model was found to be useful to supervise the fed-batch culture.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.211-214
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• 2005

Recently, Deterioration of the concrete sewer concrete structures by biochemical corrosion has been issued and a development of the inhibition system of corrosion that has been demanded. The sulfuric acid may react with the hardened cement paste and originate expansive products which can induce swelling and breakless of concrete. Also, a sulphuric acid reacts with calcium hydroxide to from $CaSO_4\;\cdot\;2H_2O$. This reaction accounts for consumption of the calcium hydroxide present in hardened cement paste. In this study, To present from biochemical corrosion of the sewer repair mortar that was spread with liquefied antibiotic and then its experimental properties were experimentally investigated and to estimate the effect of absorbed condition of restorative mortar, the number of coating times and coating contents with antibiotic on the durability properties of restorative mortar spread with antibiotics. Also, testing items such as carbonation depth, choloride ion penetration depth and chemical resistance was tested to estimate the durability properties in third study. In results, the novellus bacillus inhabiting in sewer concrete structures was restrained by antibiotics developed in this study. And carbonation depth, choloride ion penetration depth and chemical resistance of restorative mortar spread with antibiotics was superior to that of plain mortar.

• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.329-338
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• 2023

Enterohemorrhagic Escherichia coli (EHEC) is a foodborne pathogen that produces attaching and effacing lesions on the large intestine and causes hemorrhagic colitis. It is primarily transmitted through the consumption of contaminated meat or fresh produce. Similar to other bacterial pathogens, antibiotic resistance is of concern for EHEC. Furthermore, since the production of Shiga toxin by this pathogen is enhanced after antibiotic treatment, alternative agents that control EHEC are necessary. This study aimed to discover alternative treatments that target virulence factors and reduce EHEC toxicity. The locus of enterocyte effacement (LEE) is essential for EHEC attachment to host cells and virulence, and most of the LEE genes are positively regulated by the transcriptional regulator, Ler. GrlA protein, a transcriptional activator of ler, is thus a potential target for virulence inhibitors of EHEC. To identify the GrlA inhibitors, an in vivo high-throughput screening (HTS) system consisting of a GrlA-expressing plasmid and a reporter plasmid was constructed. Since the reporter luminescence gene was fused to the ler promoter, the bioluminescence would decrease if inhibitors affected the GrlA. By screening 8,201 compounds from the Korea Chemical Bank, we identified a novel GrlA inhibitor named Grlactin [3-[(2,4-dichlorophenoxy)methyl]-4-(3-methylbut-2-en-1-yl)-4,5-dihydro-1,2,4-oxadiazol-5-one], which suppresses the expression of LEE genes. Grlactin significantly diminished the adhesion of EHEC strain EDL933 to human epithelial cells without inhibiting bacterial growth. These findings suggest that the developed screening system was effective at identifying GrlA inhibitors, and Grlactin has potential for use as a novel anti-adhesion agent for EHEC while reducing the incidence of resistance.

• Journal of Oriental Neuropsychiatry
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• v.16 no.2
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• pp.125-133
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• 2005

Object : This paper is designed to inquire into the influence of eating habits on the emotion of modem people. Method : The methodology is used that searches for materials such as books and treatises on the relationship between eating habits and emotion. Result : Meat used for fast food comes from cows that are fed the feed containing growth hormone and antibiotic. Growth hormone extremely supplements fire or yang within the body while antibiotics undermines the process of yin, leading to an accumulation of damp-heat and inflammation of ministerial fire. Additives contained in instant foods also impinge on the process of yin, leading to poor digestion, damp-heat toxins and ministerial fire. Excessive consumption of meat results in incomplete combustion of fat and hinders the formation of essence. Subsequently, ministerial fire becomes hyperactive as a result of the lack of yin energy. Increased meat consumption in the human diet is coupled with unhealthy eating pattern in which people eat too much for dinner and too quickly. Eating too much disturbs digestion, making it slow and incomplete, leading to excess damp-heat conditions, insufficient amount of vital essence and eventually hyperactive ministerial fire. Milk is considered a catalyst of faster growth, making it suitable for calves. Milk intake rapidly increases the balance of yang and eventually cause hyperactivity of ministerial fire. Conclusion : It is estimated that the eating habits of modern people cause the process of yang, making them feel restless, impatient and aggressive.