• Toxicological Research
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• v.17
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• pp.305-307
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• 2001

Toluene diisocyanate (TDI) is widely used in the manufacture of polyurethanes and is a recognized cause of occupational asthma. Although extensive investigations have been undertaken, the molecular mechanism(s) of the disease is still unclear. We hypothesized that inflammatory cytokines are required during both the sensitization and elicitation phases of the disease and have utilized TNF-R knock-out (KO) mice to address the hypothesis. Black C57 TNFR knock-out mice were exposed to TDI by sc injection and challenged by inhalation of 100 ppb TDI vapor. Control animals included: wild type C57 animals, sham-exposed animals that were challenged with TDI, and animals that were injected with anti-TNF antibodies prior to sensitization and again prior to challenge. Total IgE was increased in the knock-out animals compared with the wild type sensitized and challenged animals whereas TDI-specific IgG antibodies did not differ significantly in KO and wild type animals. There was less inflammation in the nares and trachea in KO animals compared with the wild type animals exposed to TD1 as well as less goblet cell hyperplasia and epithelial damage. Airway reactivity was assessed in animals treated with anti-TNF$\alpha$ antibody and found to be substantially reduced compared with that in sensitized and challenged animals. These results indicate that TNF$\alpha$ plays a role in the immunologic and physiologic responses and in airways inflammation in this animal model and suggests a role for TNF in occupational asthma due to TDI.

• Toxicological Research
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• v.26 no.3
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• pp.223-232
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• 2010

Artesunate, a semi-synthetic derivative of artemisinin, is used primarily as a treatment for malaria. Its effects on the central nervous system, general behavior, and cardiovascular, respiratory, and other organ systems were studied using mice, rats, guinea pigs, and dogs. Artesunate was administered orally to mice at doses of 125, 250, and 500 mg/kg and to rats and guinea pigs at 100, 200, and 400 mg/kg. In dogs, test drugs were administered orally in gelatin capsules at doses of 50, 100, and 150 mg/kg. Artesunate induced insignificant changes in general pharmacological studies, including general behavior, motor coordination, body temperature, analgesia, convulsion modulation, blood pressure, heart rate (HR), and electrocardiogram (ECG) in dogs in vivo; respiration in guinea pigs; and gut motility or direct effects on isolated guinea pig ileum, contractile responses, and renal function. On the other hand, artesunate decreased the HR and coronary flow rate (CFR) in the rat in vitro; however, the extent of the changes was small and they were not confirmed in in vivo studies in the dog. Artesunate increased hexobarbital-induced sleeping time in a dose-related manner. Artesunate induced dose-related decreases in the volume of gastric secretions and the total acidity of gastric contents, and induced increases in pH at a dose of 400 mg/kg. However, all of these changes were observed at doses much greater than clinical therapeutic doses (2.4 mg/kg in humans, when used as an anti-malarial). Thus, it can be concluded that artesunate is safe at clinical therapeutic doses.

• Korean Journal of Community Nutrition
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• v.6 no.1
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• pp.84-90
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• 2001

The purpose of this study was to investigate teacher's perceptions about the nutrition education of elementary schools. A total of 226 elementary school teachers within Changwon and Milyang city participated in this study. The results of this study were as follows. 90.8% of the teachers responded that nutrition education is necessaty in the elementary schools, and positive responses in the Milyang urban area were higher than that of the Changwon rural area(p＜0.001). The main reason for the necessity of nutrition education was for proper growth and good table manners and the Milyang urban city was significantly higher than three other classes in ‘for proper growth’(p＜0.05). The starting period for nutrition education was supported by 72.1% of the teachers as beging when the children are in kindergarten, proving that this early nutrition education is supported. Especially in the Changwon urban support was higher than in the three other classes(p＜0.01). The perceptions about a suitable person to teach nutrition indicated parents(39.6%), dietitions(35.5%), class teachers(24.9%), and the beliefs about nutrition specialists or dietitions was very low. 53.6% of the teachers responded that they would not teach nutrition education themselves and the main reason for this was that believed the teacher's work would be too hard(32.0%), lack of nutrition knowledge(29.4%), and that such courses should be taught courses by specialists(29.4%). However, 51.6% of the teachers disagreed with having a separate course for nutrition education. Proper eating habits(62.7%) and growth and nutrition(28.6%) were the main categories within nutrition education. The teacher recognized that elementary students' nutrition problem is to eat too much processed and instant foods(39.1%), deviated foods(36.9%), and lack of table manners(19.4%). The most effect method was to link the subject matter with the parents(38.7%), use of audio visuals and education materials(28.3%), and need of nutrition education teachers(10.1%) was low.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.312-320
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• 2012

The purpose of this study was to investigate the perception of the school dietitian on superior agricultural products (SAP) and the status of using superior agricultural products in school meals. Questionnaires were distributed to 185 school dietitians after face to face interview, and a total of 181 responses were used for analysis. 82.3% of the respondents were using SAPs in school meals and there was a significant difference between elementary school (95.1%), middle school (76.8%) and high school (66.7%) dietitians (p < 0.001). 85.2% of the dietitians, who were using SAP, were purchasing SAPs through electronic bidding, and the main reason of not using SAPs was the higher price of SAPs than that of general agricultural products. The good agricultural practices (GAP) product was considered the most appropriate agricultural products for school meals by the majority of respondents (66.9%), and organic products was the next (13.3%). In addition, the most important selection criterion for a SAP perceived by school dietitians was safety (58.0%), and the main reason of using SAPs in school meals, when two choices were allowed, was 'to provide healthful food to children' (98.9%). The major barriers to using SAPs in school meals (two choices were allowed) were 'too expensive' (73.5%) and 'unstable supply' (32.6). In conclusion, it was suggested that there should be an improvement in SAP supply and management systems to increase the use of SAPs in school meals.

• Korean Journal of Community Nutrition
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• v.18 no.4
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• pp.324-332
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• 2013

The purpose of this study was to investigate middle school students' perception of environment-friendly agricultural products (EAPs) and the degree of confidence about the certification mark. Questionnaires were distributed to 444 students of 6 middle schools located in Daegu, and a total of 416 responses were used for analysis. 28.6% of the respondents were using EAPs at home, and 62.0% of respondents didn't know whether to use EAPs at home. The 6 items representing the perception of EAPs were analyzed, resulting in 2 distinct dimensions-'benefits of EAPs' and 'attitude toward EAPs'. Regarding Benefits of EAPs, the score of 'EAPs better for health' was the highest, followed by 'EAPs have higher quality', 'EAPs were better for environmental protection', respectively. The proportion of students responded that 'the amount of pesticides should be reduced gradually' was 65.5% and only 3.4% for 'current level of pesticide use is not a problem'. There were significant differences between male and female students with regard to an interest in EAPs (p < 0.05) and opinion on the use of pesticides (p < 0.05), while no significant difference was found between groups with different education level of mothers. The respondents who use EAPs at home showed significantly higher scores with attitude toward EAPs (p < 0.001), and higher response rate for 'pesticides should not be used even if the price increases' (p < 0.05). Degree of confidence about the EAPs certification mark also affected students' perception of EAPs (p < 0.001). Our results indicate the importance of education for students on EAPs to enhance students' attitude towards EAPs and improve school meal satisfaction.

• Journal of Microbiology and Biotechnology
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• v.15 no.4
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• pp.866-872
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• 2005

H. pylori is known to cause severe gastric diseases, including peptic ulcers and gastric cancers, and a link has also been suggested with iron-deficiency anemia (IDA). However, little is known about the pathogenesis of H. pylori-associated IDA. In the present study, to determine whether H. pylori strains are correlated with the prevalence of IDA, we analyzed and compared the sequences of the napA genes encoding a bacterioferritin-like protein in H. pylori strains. A total of 20 H. pylori strains were isolated from antral biopsies of patients with and without IDA, and the napA genes amplified from the genomic DNA were sequenced. A comparison of the deduced amino acid sequences for NapA revealed two sites with major variations. At residue 70, five out of the 12 non-IDA strains ($41.7\%$) contained serine, while only one of the 8 IDA strains ($12.5\%$) contained serine, indicating a significantly higher frequency of serine in the non-IDA strains. In addition, the NapA proteins from all 17 Western strains available on Web sites were found to contain serine residues at this position. Meanwhile, the other major variation was located at residue 73, where all eight IDA strains ($100\%$) contained leucine, while this was only true for eight of the 12 non-IDA strains ($66.7\%$). Therefore, these results indicated that the strains within each group were more genetically related to each other than to strains in the other group. When the expression level of the napA genes in the H. pylori strains was measured using RT-PCR, no significant difference was observed between the two groups, suggesting a similar intensity for the inflammatory responses induced by the NapA protein among the strains. Consequently, when taken together, the present data suggest that the occurrence of H. pylori-associated IDA may be partly determined by the infecting H. pylori strain, and the non-IDA strains are more closely related to Western strains than the IDA strains.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.379-386
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• 2011

The objective of this work was to investigate the ability of the plant growth-promoting rhizobacterium Pseudomonas aureofaciens 63-28 to induce plant defense systems, including defense-related enzyme levels and expression of defense-related isoenzymes, and isoflavone production, leading to improved resistance to the phytopathogen Rhizoctonia solani AG-4 in soybean seedlings. Seven-day-old soybean seedlings were inoculated with P. aureofaciens 63-28, R. solani AG-4, or P. aureofaciens 63-28 plus R. solani AG-4 (P+R), or not inoculated (control). After 7 days of incubation, roots treated with R. solani AG-4 had obvious damping-off symptoms, but P+R-treated soybean plants had less disease development, indicating suppression of R. solani AG-4 in soybean seedlings. Superoxide dismutase (SOD) and catalase (CAT) activities of R. solani AG-4-treated roots increased by 24.6% and 54.0%, respectively, compared with control roots. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities of R. solani AG-4-treated roots were increased by 75.1% and 23.6%, respectively. Polyphenol oxidase (PPO) activity in soybean roots challenged with P. aureofaciens 63-28 and P+R increased by 25.0% and 11.6%, respectively. Mn-SOD (S1 band on gel) and Fe-SOD (S2) were strongly induced in P+R-treated roots, whereas one CAT (C1) and one APX (A3) were strongly induced in R. solani AG-4- treated roots. The total isoflavone concentration in P+Rtreated shoots was 27.2% greater than the control treatment. The isoflavone yield of R. solani AG-4-treated shoots was 60.9% less than the control.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.56-60
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• 2001

Background: Conventional thoracoscopic sympathectomy or sympathicotomy is an effective method in treating localized hyperhidrosis; however, this may result in a postoperatively compensatory hyperhidrosis or facial anhidrosis in the treatment of palmar hyperhidrosis. We modified the conventional sympathicotomy by limiting the extent of nerve transection (limited T3 sympathicotomy) since May 1998. However, there are many reports of a good short-term outcome of limited T3 sympathicotomy. Therefore, we reviewed long-term follow-up of limited T3 sympathicotomy based on outcomes analysis using a questionnaire. Methods: Fifty four patients with palmar hyperhidrosis underwent a limited T3 sympathicotomy between May 1998 and March 1999 and had a complete follow-up over two years using a questionnaire (the mean follow-up was 2.6 years). The patients' postoperative satisfaction was determined by their subjective responses to the questionnaires; the degree of compensatory hyperhidrosis, the effects on foot hyperhidrosis, gustatory hyperhidrosis and facial dryness, and recurrence, and patient's satisfaction. Results: Of the total, 87% of patients had a compensatory hyperhidrosis and 3.7% of them were disabled. 31.5% of patients showed improvement in foot hyperhidrosis, while 68.5% of patients demonstrated no change or got worse. 31.5% of patients had gustatory hyperhidrosis and facial dryness and 22.2% of patients showed a mild palmar hyperhidrosis. The postoperative patients' satisfaction was significantly in 96.3% of patients. Conclusions: The limited T3 sympathicotomy is a highly effective treatment of palmar hyperhidrosis and has a low rate of postoperative compensatory hyperhidrosis, gustatory hyperhidrosis, and facial dryness.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.227-232
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• 2011

This survey was conducted to investigate the current status of swine artificial insemination(AI) centers registered as 'semen processing business' in Korea. The survey responses were collected by direct visitation or telephone conversation for 5 months from May through September in 2008. The survey showed that sixty-four AI centers were enrolled in local government and those of fifty-two AI centers were under operation. Forty-nine AI centers surveyed owned a total of 3,334 boars and the Duroc breed accounted for the highest rate(73.1%) of all boar breeds. In type of ownership, agricultural management corporations was the highest(42.3%) and followed by private ownership(34.6%). Large-scale AI centers in terms of own over 151 boar were surveyed as 5.9% and most AI centers own less than 100 boars(86.5%). The average number of boars per AI center was 68. The amount of liquid semen provided by 52 AI centers were 1,791,000 doses and each AI center provides average of 39,000 does, which is represented for 90% consumption by sows in Korea.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.335-342
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• 2019

The purpose of this study was to investigate the toxic effects of zinc in collembolan Paronychiurus kimi at the individual (survival and juvenile production) and population (population growth and age structure) levels after 28 days of exposure in artificially spiked soil. These toxic effects were interpreted in conjunction with the internal zinc concentrations in P. kimi. The EC₅₀ value for juvenile production based on the total zinc concentration was 457 mg Zn kg^-1 dry soil, while the LC₅₀ value for adult survival and r_i=0 value for population growth were within the same order of magnitude (2,623 and 1,637 mg Zn kg^-1 dry soil, respectively). Significant differences in adult survival, juvenile production, and population growth compared with the control group were found at concentrations of 1,500, 375, and 375 mg Zn kg^-1 dry or higher, respectively, whereas significant differences in the age structure, determined by the proportion of each age group in the population, were observed in all treatment groups. It appeared that the internal zinc level in P. kimi was regulated to some extent at soil zinc concentrations of ≤375 mg Zn kg^-1 dry soil, but not at high soil zinc concentrations. These results indicate that, despite zinc being regulated by P. kimi, excess zinc exceeding the regulatory capacity of P. kimi can trigger changes in the responses at the individual and population levels. Given that population dynamics are affected not only by individual level but also by population level endpoints, it is concluded that the toxic effects of pollutants should be assessed at various levels.