Purpose : Infection with Shiga-like toxin (SLT)-producing Escherichia coli, an emerging human pathogen found particularly in young children under 5 years of age, causes a spectrum of illnesses with high morbidity and mortality, ranging from diarrhea to hemorrhagic colitis and hemolytic uremic syndrome. Host mediators play an important role in the pathogenesis of SLT-I toxicity. The experiments described here were designed to investigate the effect of SLT-I on TNF-${\alpha}$ production and to understand the effect of TNF-${\alpha}$ on GB3 expression. We also further examine the relationship between the Gb3 level and the differential susceptibility of cells to the cytotoxic action of SLT-I. Methods : The effect of purified SLT-1 from E. coli O157 : H7 (ATCC 43890) on tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) production in Raw264.7 cells was investigated. Many mediators regulate endothelial cell membrane expression of the glycolipid globotriaosyleramide (Gb3), which serves as the toxin receptor, suggesting that the host response to the toxin or other bacterial products may contribute to pathogenesis by regulating target cell sensitivity to the toxins. Therefore, the relationships between Gb3 expression and cytotoxicity against SLT-I on three types of cells were evaluated. Results : Detectable levels of TNF-${\alpha}$ were produced as early as six hours after induction and continued to increase during 48 hours by SLT-I. It was also found that Vero cells and dendritic cells (DC2.4 cells) expressed high levels of Gb3, 83% and 68%, respectively, and that Raw264.7 cells had a low level of Gb3 (29%) and appeared refractory to cytotoxicity against SLT-I. Vero cells and DC2.4 cells expressing high levels of Gb3 were highly susceptible to SLT-I. Furthermore, macrophages showed a resistance to SLT-I cytotoxicity, despite the fact that Gb3 expression was enhanced. Conclusion : These results strongly suggest that the expression of Gb3 is necessary but not sufficient to confer sensitivity of macrophages to SLT-I and further underpin the important role of SLT-I and its Gb3 receptors in the pathogenesis of E. coli O157 infection.
BACKGROUND: Aclonifen is used as a systemic and selective herbicide to control a wide spectrum broad-leaf weeds by inhibition carotenoid biosynthesis, and then its MRLs(Maximum Residue Limits) will be determined in onion and garlic. In this study, a new official method was developed for aclonifen determination in agricultural products to routinely inspect the violation of MRL as well as to evaluate the terminal residue level. METHODS AND RESULTS: Aclonifen was extracted from crop samples with acetone and the extract was partitioned with dichloromethane and then purified by silica solid phase extraction(SPE) cartridge. The purified samples were detected GC using an ECD detector. Limits of detection(LOD) was 0.001 mg/kg and quantification(LOQ) was 0.005 mg/kg, respectively. For validation purposes, recovery studies were carried out at three different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$, n=5). The recoveries were ranged from 74.3 to 95.0% with relative standard deviations(RSDs) of less than 8%. All values were consistent with the criteria ranges requested in the Codex guidelines(CAC/GL 40). CONCLUSION: The proposed analytical method was accurate, effective and sensitive for aclonifen determination and it will be used to as an official method in Korea.
Kim, Min-Ji;Choi, Hee-Chul;Suh, Ok-Suk;Chae, Hyun-Suk;Na, Jae-Cheon;Bang, Han-Tae;Kim, Dong-Wook;Kang, Hwan-Ku;Park, Sung-Bok
Korean Journal of Poultry Science
/
v.37
no.4
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pp.383-388
/
2010
The chicken eye can discriminate light color, and different light wavelengths may affect reproduction ability. This study was carried out to identify effect of monochromatic light using light emitting diode (LED) in laying hens. Chickens were exposed to white light (WL), blue light (BL), yellow light (YL), green light (GL) and red light (RL) made by using LED as well as incandescent light (IL) (control). All light sources were equalized to a light intensity of 20 lux. The results indicated that the age of first egg laying and 50 % egg laying in laying hens treated under RL is significantly younger than under other lights (P<0.05). And the ovary weight of laying hens reared under RL is significantly heavier than under other at from 16 to 20 wks (P<0.05). The largest number of eggs production was produced in a group with treated with RL by 59 wks of age compared with any other group. The egg weight of YL was greater than other treatment groups from 26 to 45 wks (P<0.05). The egg shell from hens treated with RL was the strongest and thickest at 20 wk (P<0.05). These results suggest that the egg quality of laying hens reared in different spectrum of LED can be different and RL may enhance the laying performance.
The long term stability of ion current of QMS has been one of key parameters for monitoring gas process in vacuum. The time dependence of ionic current was monitored while the pressure of nitrogen gas was kept at a fixed pressure by introducing the gas into vacuum chamber. The chamber was evacuated to ${\sim}3{\times}10^{-9}\;Torr$ to reduce background signals before the measurement. Two ion sources were tested; one had brownish or black color due to gas contamination and the other one was new, i.e. cleaner. At a nitrogen pressure of $1{\times}10^{-5}\;Torr$, the ionic currents measured by the contaminated ion source decreased faster with time. The decrease rate was respectively ${\sim}46%$ for cleaner one and ${\sim}84%$ for contaminated one after ${\sim}5.5%$ hours. In order to test the effect of filament material on the ion current decrease, we fabricated a tungsten(W) filament which consisted of two parts; one half was made of W and the other was coated with yttria. The similar decrease of ionic currents were shown for the two types of filaments, indicating that slight change of temperature of filament due to material difference i.e. baking effect could not improve the origin of ionic current decrease. Overall the decreasing rate of ionic current is more closely associated with contaminated ion source of QMS rather than its filament materials.
Journal of the Korea Academia-Industrial cooperation Society
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v.14
no.5
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pp.2329-2337
/
2013
This study was done objected to the chronic stroke patients in order to evaluate change in brain wave activity and cognitive performance when Neurofeedback training. The subjects were over 6 months ago in chronic stroke patients screened-test through the 20 patients, 10 persons in each group were randomly placed. This was carried out in 4 weeks in total, with control group(n=10) on general physical therapy and experimental group(n=10) on general physical therapy along with Neurofeedback training. The general physical therapy was applied 5 times a week, 30 minutes at once, Neurofeedback training was applied as equally as the general physical therapy, which makes 20 times in total. To learn about the effect before the training, after training, and 2 weeks after the training in electric physiological measurement method of the brain, electroencephalogram(EEG) to examine challenges by calculating the absolute spectrum power for standard EEG change(%), followed by evaluation with clinical assessment tool MMSE-K, Stroop Test, Digit Span Test. As a result of comparing the change in brain wave through EEG, after training and 2 weeks after training showed that absolute ${\alpha}$-power and absolute ${\beta}$-SMR power of experimental group have increased and absolute ${\theta}$-power decreased significantly compared to experimental group I. Moreover, the MMSE-K score in trial appraisal has increased significantly, and the error in Stroop Test and Digit Span Test has decreased significantly. such results, with the chronic stroke patient's brain wave control, Neurofeedback training was determined to improve the cognitive performance. this study suggests a new training possibility of stroke patients by identifying the training effects of Neurofeedback training that trains the brain directly with brain wave control.
Purpose: We examined the roles of Ultrasonography conductors by analyzing the results of tissue biopsy of complex cystic masse under the guidance of breast US. Objects and methods: This study was performed to a group of 178 who showed breast US indicating complex cystic masses among 342 patients who were definitely diagnosed by tissue biopsies and operations in our hospital from June 30th, 2003 to June 30th, 2007. The evaluation of tissues around, calcification, the distribution state of blood flow were excluded from the analysis subjects and logic 200 made by GE corporation and gun for core biopsy(Kimal corp., K7/MBD23) were used in this study. Results: The biopsy results of 178 subjects showed FCC (fibrocystic change)(n=56 : 31.4%), Fibrosis (n=41 : 23.0%), Fibroadenoma (n=20 : 11.2%), Epithelial hyperplasia (n=17 : 9.6%), Carcinoma (n=15 : 8.4%), Fibroadipose (n=8 : 4.5%), Sclerosing adenosis (n=7 : 3.9%), Duct ectasia (n=5 : 2.8%), Papiloma (n=5 : 2.8%), and Fat necrosis (n=1 : 0.6%), Hemangioma (n=1 : 0.6%), Abscess (n=1 : 0.6%), Dystrophic calcification(n=1 : 0.6%). Conclusion: The US showed that the results of the tissue biopsy of complex cystic masses were mostly carcinoma(8.4%). Most of them were benign and only 9.6% of epithelial hyperplasia which has high progression rate into malignant tumors epidemically showed malignancy. Most of them were included in the spectrum of fibrous cystic nodule. Even though these results are confirmed, further studies are required. As a result, a nodule which is not certified by US should be right to take the tissue biopsy, but if it's difficult due to patients or another reasons, re-check tests in three months are required. And systemic ultrasonography evaluation should be well recognized to conduct more careful and specific tests.
This study was conducted to establish optimized ${\beta}-glucan$ extraction method through enzymatic hydrolysis from Phellinus baumii and investigate ${\beta}-glucan$ contents and physicochemical properties. The optimal condition was obtained with the enzyme concentration of 0.66% (v/v), reaction time of 6.08 h ($R^2=0.9245$) and the ${\beta}-glucan$ contents from the Phellinus baumii extracts under the optimized condition was 1.9594 g/100 g. ${\beta}-Glucan$ yield (0.76-16.40%) of enzyme beta-glucan extract (EBE) was three fold higher than that of non-enzyme beta-glucan extract (NEBE). ${\beta}-Glucan$ purity (11.15-59.05%) of non-enzyme beta-glucan (NEB) and that of enzyme beta-glucan (EB) were higher than that of NEBE and that of EBE. ${\beta}-Glucan$ purity of EB (59.05%) and ${\beta}-glucan$ contents of EB (3.38 g/100 g) showed higher than those of others. Total sugar contents (0.61-1.17 mg/mL) showed that NEB and EB were higher than that of NEBE and EBE, EB had the highest total sugar content as 1.17 mg/mL, respectively. Protein contents (0.44-11.73 mg/mL) of NEBE and that of EBE were higher than that of NEB, that of EB. In FT-IR spectrum, the band at $890cm^{-1}$ of microcapsule was attributed to a ${\beta}-1,3-glucan$. The toxicities of ${\beta}-glucan$ from Phellinus baumii in both melanoma cell lines was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoli um bromide assay and ${\beta}-glucan$ from Phellinus baumii has no toxicity until $30{\mu}g/mL$. The effects of ${\beta}-glucan$ from Phellinus baumii on inhibition of cancer cell proliferation were detected by using a wound healing assay. The effect of NEB and EB were higher than NEBE and EBE, especially $30{\mu}g/mL$ of EB had the highest in both melanoma cell lines.
Activity ratio of two radioactive primary fission products which had sufficiently different half-lives was expressed as functions of cooling time and irradiation histories in which average burnup, irradiation time, cycle interval time and the dominant fissile material of the spent fuel were included. The gamma-ray spectra of 36 samples from 6 spent PWR fuel assemblies irradiated in Kori unit-1 reactor were obtained by a spectrometric system equipped with a high purity germanium gamma-ray detector. Activity ratio $^{l44}$Ce $^{l37}$Cs, analyzed from each spectrum, was used for the calculation of cooling time. The results show that the radioactive fission products $^{l44}$Ce and $^{l37}$Cs are considered as useful monitors for cooling time determination because the estimated cooling time by detection of activity ratio $^{l44}$Ce $^{l37}$Cs agreed well with the operator declared cooling time within relative difference of $\pm$5 % despite the low counting rate of the gamma-ray of $^{l44}$Ce (about 10$^{-3}$ count per second). For the samples with several different irradiation histories, the determined cooling time by modeled irradiation history showed good agreement with that by known irradiation history within time difference of $\pm$0.5 year. From this result, it would be expected to be possible to estimate reliably the cooling time of spent nuclear fuel without the exact information about irradiation history. The feasibility study on identification of and/or sorting out spent nuclear fuel by applying the technique for cooling time determination was also performed and the result shows that the detection of activity ratio $^{l44}$Ce $^{l37}$Cs by gamma-ray spectrometry would be usefully applicable to certify spent nuclear fuel for the purpose of safeguards and management in a facility in which the samples dismantled or cut from spent fuel assemblies are treated, such as the post irradiation examination facility.mination facility.
Background: Surgical correction of the full spectrum of esophageal atresia with tracheoesophageal fistula has improved over the years, but the mortality and morbidity assoiated with repair of these anomalies still remains high. Material and Method: We retrospectively analyzes 27 surgically treated patients with esophageal atresia and tracheoesophageal fistula at Dong-A University Hospital between January 1992 and March 1997. Result: There were 21 male and 6 female patients. Mean birth weight was 2.62$\pm$.385 kg(2.0~3.4 kg). Twenty- four(88.9%) had esophageal atresia with distal tracheoesophageal fistula, and 3(11.1%) had pure esophageal atresia. Four(14.8%) infants were allocated to Waterston risk group A, 18(66.7%) to group B, and 5(18.5%) to group C. In eighteen(66.7%) infants with associated anomalies, cardiovascular anomalies were the most common. Three had a gap length of 3.5 cm or greater(ultra-long gap) between esophageal segments, 7 had 2.0 to 3.5 cm(long gap), 8 had 1.0 to 2.0 cm(medium gap), and 9 had 1 cm or less(short gap) gap length. Among 27 neonates, 3 cases underwent staged operation, late colon interposition was done in 2, and all other 24 cases underwent primary esophageal anastomosis. Oerative mortality was 2/27(7.4%). Causes of death included acute renal failure(n=1), empyema from anastomotic leak(n=1), necrotizing enterocolitis(n=1), sepsis(n=1), insulin-dependent diabetus mellitus(n=1 . There were 4 anastomosis- related complications including stricture in 3, leakage in 1. Mortality was related to the gap length(p<.05). Conclusion: Although the complication rate associated with surgical repair of these anomalies is high, this does not always implicate the operative mortality. The overall survival can be improved by effective treatment for combined anomalies and intensive postoperatve care.
Microorganisms near the plant rhizosphere usually inhabit the surface or the inside of the plant roots and have a direct effect on plant growth by secreting plant growth promoters or antagonistic materials which protect the root zone system from various pathogens. This study was carried out to identify and isolate the antagonistic materials after isolation of microorganisms showing high antagonistic activities, in hopes of contributing to the development of sustainable agriculture and the preservation of agricultural environments. A number of antagonistic bacteria were isolated from paddy soil. Among isolates, RRj 228 showed plant growth promotion and antagonistic activity. RRj 228 was identified as Pseudomonas sp. according to the results of physiological properties and genetic methods. On the basis of the results of anti-fungal spectrum against several pathogens by RRj 228, the antagonistic effect of the isolate against Botrytis cinerea, Pythium ultimum, Phytopthola capsici, and Rhizoctonia solani, especially against red-pepper anthracnose caused by Colletotrichum acutatum, was remarkable. The experiment evaluating the biological control effect by RRj 228 revealed that the $ED_{50}$ value by the RRj 228 culture against C. acutatum, R. solani and P. ultimum were 0.14 mg/ml, 0.16 mg/ml and 0.29 mg/ml, respectively. An antagonistic substance was isolated and purified by several chromatographies from the RRj 228 culture. The $^1H$ and $^{13}C$ assignment of the antagonistic substance was achieved from two-dimensional $^1H-^1H$ COSY, HMQC, and HMBC. Finally, the antagonistic substance was identified as Phenazine-1-carboxylic acid ($C_{13}H_8N_2O_2$, M.W.=224).
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