• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.166-172
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• 2022

This study evaluated the migrant and residue tests of lead (Pb), cadmium (Cd), nickel (Ni), arsenic (As), and antimony (Sb) in 70 tumbler samples. The migration levels of hazardous metals in all the samples were within the migration limits outlined in the Korean standards and specifications for utensils, containers, and packages. Moreover, in all the tumbler samples, only Ni was detected in 0.5% citric acid solution of a food stimulant. The maximum level of Ni 0.0144 mg/L was 14.4% of the migrant specification (not more than 0.1 mg/L), which was relatively safe. The 0.5% citric acid solution was eluted at 4℃, 70℃, and 100℃ for 30 min, and only Ni was detected while testing for migration levels according to the temperature variations; all temperature conditions conformed to the standards. The level of Ni migration increased significantly with increasing migration temperature. Regarding the residue level outside the paint-coated tumbler samples, the Pb level was found to range from N.D. to 20638.1323 mg/kg. The risk of Ni was further estimated to be at a safe level of 0.00 to 0.01% compared to the %TDI as a result.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.231-237
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• 2006

Nowadays the teabag is worldwide used for various products including green tea, tea, coffee, etc. since it is convenient for use. In case of outer packaging printed, however, there is a possibility that the plasticizers which is used for improvement in adhesiveness of printing ink may shift to inner tea bag. In this study, in order to monitor residual levels of plasticizers in teabags, we have established the simultaneous analysis method of 9 phthalates and 7 adipates plasticizers using gas chromatography (GC). These compounds were also confirmed using gas chromatography-mass spectrometry (GC-MSD). The recoveries of plasticizers analyzed by GC ranged from 82.7% to 104.6% with coefficient of variation of $0.6\sim2.7%$ and the correlation coefficients of each plasticizer was $0.9991\sim0.9999$. Therefore this simultaneous analysis method was showed excellent reproducibility and linearity. And limit of detection (LOD) and limit of quantitation (LOQ) on individual plasticizer were $0.1\sim3.5\;ppm\;and\;0.3\sim11.5\;ppm$ respectively. When 143 commercial products of teabag were monitored, no plasticizers analysed were detected in filter of teabag products. The migration into $95^{\circ}C$ water as food was also examined and the 16 plasticizers are not detected. In addition we carried out analysis of heavy metals, lead (Pb), cadmium (Cd), arsenic (As) and aluminum (Al) in teabag filters using ICP/AES. $Trace\sim23{\mu}g$ Pb per teabag and $0.6\sim1718{\mu}g$ Al per teabag were detected in materials of samples and Cd and As are detected less than LOQ (0.05 ppm). The migration levels of Pb and Al from teabag filter to $95^{\circ}C$ water were upto $11.5{\mu}g\;and\;20.8{\mu}g$ per teabag, respectively and Cd and As were not detected in exudate water of all samples. Collectively, these results suggest that there is no safety concern from using teabag filter.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.26-33
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• 1988

To investigate the effects of paper sludge on the growth response of paddy rice, paper sludge was applied to pots at the rate of either 300, 600, 900 or 1,200 kg/l0a which was either preadjusted at a C/N ratio of 30 : 1 or not adjusted. The effects were compared with those of the control. 1. Plant heights, number of tillers and dry weight were significantly reduced with the increasing application of paper sludge in the early stages of rice growth, whereas opposite results were observed after the heading stage when treated with C/N ratio preadjusted paper sludge. 2. The uptake of $N,P_2O_5,K_2O$ and $SiO_2$ by rice plants grown in paper sludge treated soil was significantly reduced in the early stages of rice growth. Conversely, uptake was enhanced in the C/N ratio preadjusted plot in the young panicle formation stage. 3. Zn, Cu and Cd content in rice straw was in the range of $39{\sim}101$, $0{\sim}0.11$ and $0.03{\sim}0.14ppm$, respectively, and Pb and Cr in rice straw were not detected at all. However, there was no difference in the content of all these heavy metals in rice straw irrespective of treatment.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.232-245
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• 1995

The garbage from the dwelling house was composted in two kinds of small composter in the laboratory, and the possibility of garbage composting was examined. The composters were general small. One (type 3) was constructed with the double layer walls and the other (type 4) was the same as the first except for being insulated. Because it was found that type 3 was not available for composting under our meteorological conditions through the winter experiment, only type 4 was tested in spring and summer. The experiment was performed for 8 weeks in each season. The seasonal variation of several components in the compost was evaluated and discussed. The results summarized below were those obtained at the end of the experiment, if the time was not specified. 1) The maximum temperature was $43^{\circ}C$ in winter, $55^{\circ}C$ in spring and $56^{\circ}C$ in summer. 2) The mass was reduced to an average of 63% and the volume reduction was an average of 78%. 3) The density was estimated as 1.5 kg/l in winter and 0.8 kg/l in spring and summer. 4) The water content was not much changed during the composting periods. It was 79.3% in winter, 75.0% in spring and 70.0% in summer. 5) After pH value increased during the first week, it decreased until the second week and increased again continuously thereafter. It reached pH 6.19 in winter, pH 7.59 in spring and pH 8.69 in summer. 6) The faster the organic matter was decomposed, the greater the ash content increased. The contents of cellulose and lignin increased, but that of hemicellulose decreased during the composting period. 7) Nitrogen contents were in the range of 3.3-6.8% and especially high in summer. After ammonium contents increased at the early stage of the composting period, they decreased. The maximum ammonium-nitrogen content was 2,404mg/kg after 8 weeks in winter, 12,400mg/kg after 3 weeks in spring and 20,718mg/kg after 3 weeks in summer. C/N-ratios decreased with the lapse of composting time, but they were not much changed. Nitrification occurred actively in summer. 8) The contents of volatile and higher fatty acids increased at the early stage of composting and reduced after that. The maximum content of total fatty acid was 9.7% after 6 weeks in winter, 14.8% after 6 weeks in spring and 15.8% after 2 weeks in summer. 9) The contents of inorganic components were not accumulated as composting proceeded. They were in the range of 0.9-4.4% $P_2O_5$, 1.6-2.4% $K_2O$, 2.2-5.4% CaO and 0.30-0.61% MgO. 10) CN and heavy metal contents did not show any tendency. They were in the range of 0.21-14.55mg/kg CN, 11-166mg/kg Zn, 5-65mg/kg Cu, 0.5-10.8mg/kg Cd, 6- 35mg/kg Pb, ND-33 mg/kg Cr and ND-302.04 g/kg Hg.

• Korean Journal of Pharmacognosy
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• v.24 no.4
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• pp.267-281
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• 1993

To find antitumor components from higher fungi, the mycelia of Collybia confluens (Pers. ex Fr.) Kummer were cultured in artificial media. For efficient production of the mycelia, the influences of various modifications of culture conditions were examined. A water-soluble protein-bound polysaccharide fraction, Fr. A, was obtained from the mycelia by hot water extraction. When Fr. A was purified and fractionated by DEAE-cellulose and Sepbadex G-200 gel filtration chromatographies into four fractions which were designated B, C, C-I and C-II. The tumor inhibition ratios of these fractions ranged from 46% to 75% against the solid forms of sarcoma 180 in ICR mice at doses of 20 and 50 mg/kg/day when given intraperitoneally. Especially, Fr. C which was named Collyban(CB) exhibited a marked life-prolonging effect of the mice against ascitic forms of sarcoma 180 at a dose of 50 mg via i.p. administration. To extend spectra of the antitumor activities and eliminate the effects of allograft rejection, the characterization of antitumor effects of CB was performed in syngeneic host-tumor systems. It did not show any antitumor activity against L1210 murine leukemia in $CD_2Fl$ mice but prolonged their life span against ascitic forms of $MM_{46}$ carcinoma in $C_3H/He$ mice. Also it exhibited antitumor activity against human cervical cancer HeLa cells that were xenografted into nude mice having BALB/c genetic backgrounds by the i.p. injection at a dose of 100 mg/kg/day. In order to characterize the antitumor components, CB was examined by chemical analysis. It was acidic protein-bound polysaccharides composed of 31% polysaccharide, 27% protein and 3% hexosamine. CB was fractionated into two fractions, Fr. C-I(M.W.: 500 Kd) and Fr. C-II(M.W.:30 and 8 Kd) by Sephadex G-200 gel filtration chromatography.

• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.675-685
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• 2018

Purpose: This study aims to determine the efficacy and safety of house dust mite (HDM)-sublingual immunotherapy (SLIT) in elderly patients with AR. Methods: A total of 45 patients aged ${\geq}60years$ with HDM-induced AR who had ${\geq}3$ A/H ratio on skin prick test and/or ${\geq}0.35IU/L$ to both Dermatophagoides farinae and Dermatophagoides pteronyssinus by ImmunoCAP were enrolled in 4 university hospitals. To evaluate additional effects of HDM-SLIT, they were randomized to the SLIT-treated group (n = 30) or control group (n = 15). Rhinoconjunctivitis total symptom score (RTSS), rhinoscopy score, Korean rhinoconjunctivitis quality of life questionnaire, rhinitis control assessment test, asthma control test scores, and adverse reactions, were assessed at the first visit (V1) and after 1 year of treatment (V5); for immunological evaluation, serum levels of HDM-specific immunoglobulin A/IgE/IgG1/IgG4 antibodies and basophil response to HDMs were compared between V1 and V5 in both groups. Results: There were no significant differences in demographics, RTSS, skin reactivity to HDMs, or serum total/specific IgE levels to HDMs (P > 0.05, respectively) between the 2 groups. Nasal symptom score and RTSS decreased significantly at year 1 in the 2 groups (P < 0.05). There were no significant differences in percent decrease in nasal symptom score and RTSS at year 1 between the 2 groups (P > 0.05); however, rhinoscopic nasal symptom score decreased significantly in the SLIT-treated group (P < 0.05). Immunological studies showed that serum specific IgA levels (not specific IgE/IgG) and CD203c expression on basophils decreased significantly at V5 in the SLIT-treated group (P = 0.011 and P = 0.001, respectively), not in the control group. The control group required more medications compared to the treatment group, but there were no differences in adverse reactions. Conclusions: It is suggested that HDM-SLIT for 1 year could induce symptom improvement and may induce immunomodulation in elderly rhinitis patients.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.363-372
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• 1997

One hundred forty-four patients underwent operation for coarctation of the aorta at Seoul National University Children's Hospital between June 1986 and Decembsr 1995. Age ranged 0.1 to 191 months. Of these 78.5%(113) were infants. We classified the patients in terms of the anatomic location of coarctatiln and the associatCd anomalies(I[401= primary coarctation, 11(741=isthmic hypoplasia, lIIf30)=tubular hypoplasia involving transverse arch, Ar63 =with ventricular septal defect, B(28)=with other major cardiac defects). Subcalvian flap coarctoplasty(60), resection & anastomosis(44), extended aortoplasty(26), and onlay patch(14) were used as surgical methods. Overall operative mortality was 16.0(23/144)%. The hospital mortality was signific'antly higher in patheints with type 111, subtype B, younger age(under 3 months), extended aortoplasty(p(0.01). However, one-stage total repair in patients with subtype A or B were not found to be a predictor of hospital death. Restenosis had occured in 18 patients among 121 survivals(14. 9%). The mean follow-up period was 29.1 $\pm$28.8(0~129.2) months. Preoperative, immediate postoperative(within 3 months after operation) and postoperative(later than 6 months after operation) echocardiographic data on the dimensions of ascending aorta(AA), transverse arch(TA), an4 aortic isthmus(Al) were available in 77 patients(I=20, ll=42, 111= 15). Preoperative and postoperative aortic isthmus(All) and tra sverse arch indices(TAI), defined as TAIAA & AIIAA respectively, were compared. Immediate postoperative All in type 1, II and TAI in type 111 were significantly smaller in stenotic than non-stenotic group suggesting incomplete relieves of stenotic segment Younger age, subclavian coarctoplasty in patient under 3 months of age were round to be the risk factors for restenosis in this series. In conclusion, We found that aortic arch index and transverse arch index can be a useful tool to figure out the anatomic and clinical characteristics of the patients with aortic coarctation, and that anatomy, associated anomalies, age, and surgical methods may influence the surgical outcome of the coarctation repair.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.361-369
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• 1997

A microbiological nitrate determination method by E. coli is modified in Korea, using K12 wildtype, KCTC 1116, for the quantitative reduction of $NO_3{^-}$ to $NO_2{^-}$. The nitrate in plant, soil or water sample is determined spectrophotometrically after being diazotized with sulfaniamide and N-(1-naphthl)-ethlenediamine. The modified E. coli cell method and principle for nitrate determination using Korean wildtype E. coli strain is described, and cell culture and preparation of stock suspension for E. coli as well. This modified E. coli cell method can be managed simply and fast, it is suitable for the investigation of the large serials, it can be also automated and has a high degree of sensitivity up to 0.01ppm $NO_3{^-}-N$ in the sample solution. The applicability of the modified E. coli cell method has been tested for plant, soil and water analysis on a wide range of different samples. Recovery rates of added nitrate have been determined and comparisons with other standard nitrate analytical procedures have been carried out. The results with the modified E. coli cell method show high correlation ($r^2=0.98$) with those gained by the standard analytical procedures. The advantages and disadvantages of the method are also discussed to other nitrate determination methods.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.1
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• pp.25-34
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• 2019

Objectives : This study aimed to compare the psychosocial characteristics among patients with functional gastrointestinal disorder (FGID), adults with functional gastrointestinal symptoms, and normal control group and investigate factors related to quality of life (QoL) of FGID patients. Methods : 65 patients diagnosed with FGID were selected. 79 adults were selected as normal control group based on the Rome III diagnostic criteria, and 88 adults who showed functional gastrointestinal symptoms were selected as "FGID positive group". Demographic factors were investigated. Psychosocial factors were evaluated using the Korean-Beck Depression Inventory-II, Korean-Beck Anxiety Inventory, Korean-Childhood Trauma Questionnaire, Multi-dimensional Scale of Perceived Social Support, Connor-Davidson Resilience Scale and WHO Quality of Life Assessment Instrument Brief Form. A one-way ANOVA was used to compare differences among groups. Pearson correlation test was used to analyze correlations between QoL and psychosocial factors in patients with FGID. Results : There were group differences in the education level. Depression (F=29.012, p<0.001), anxiety (F=27.954, p<0.001) and Childhood trauma (F=7.748, p<0.001) were significantly higher in FGID patient group than in both FGID-positive and normal control group. Social support (F=5,123, p<0.001), Resilience (F=9.623, p<0.001) and QoL (F=35.991, p<0.001) were significantly lower in the FGID patient group than in others. QoL of FGID patients showed a positive correlation with resilience (r=0.475, p<0.01), and showed a negative correlation with depression (r=-0.641, p<0.01), anxiety (r=-0.641, p<0.01), and childhood trauma (r=-0.278, p<0.05). Conclusions : FGID patients have distinctive psychosocial factors compared to the both FGID-positive and normal control group. Therefore, the active interventions for psychosocial factors are required in the treatment of patients with FGID.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.2-4
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• 1998

Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.