• Korean Journal of Weed Science
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• v.12 no.2
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• pp.89-101
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• 1992

In this study, various physiological and biochemical experiments were conducted to know whether the selectivity between rice and barnyardgrass treated with bleaching herbicides containing diphenyl ether compounds was also partly based on their basic physiological proterties such as peroxidation ability, membrane stability or antioxidant system. It seemed to be partly based on the differences of their physiological characteristics that barnyardgrass was commonly more susceptible to most of the bleaching herbicides than rice. The scenescence of intact leaf segment was more rapid in barnyardgrass than in rice, indicating that barnyardgrass is weak at early stage. Also pigment metabolic ability, antioxidant enzyme activities(peroxidase, catalase, superoxide dismutase, glutathione reductase) and antioxidant content (tocopherol, ascorbic acid, glutathione, carotenoids) were lower in barnyardgrass on the basic of fresh weight. However, lipoxygenase activity and the content of unsaturated fatty acid which is vulnerable to oxygen radicals were higher in barnyardgrass, suggesting that barnyardgrass seedling bave a properties easy to be peroxidized. The differences of PPIX (protoporphyrin IX) or carotenoid content, which are the primary substances inducing herbicide activity, were not related to the selectivity between rice and barnyardgrass.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.33-39
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• 1982

Carpophores of ten Korean strains of Lentinus edodes (Berk.) Singer, an antitumor polysaccharide producing fungus, were extracted with 0.1N NaOH solution. The extracts were dialized for seven days in distilled water and lyophilized to produce crude polysaccharide powders. Thus obtained crude polysaccharide samples were assayed for sugar contents by colorimetric method with anthrone reagent. Among ten strains examined Lentinus edododes-DMC7 was found to be the richest strain in polysaccharide content of carpophores. By shake culture experiment for biomass production, L. edodes-DMC7 was found to be the second most productive strain among seven strains examined. Cultural characteristics of L. edodes-DMC7 were investigated by shake culture method. The best result was obtained when L. edodes-DMC7 was cultured in the medium containing glucose 8g, starch 80g, yeast extract 12g, $KH_2PO_4\;0.87g,\;MgSO_4{\cdot}7H_2O\;O.5g,\;CaCl_2\;0.3g,\;FeSO_4{\cdot}7H_2O\;10mg\;ZnSO_4{\cdot}7H_2O\;4mg,\;CuSO_4{\cdot}5H_2O\;lmg,\;MnCl_2{\cdot}4H_2O\;7mg\;per\;11\;at\;28^{\circ}C$, 180 rpm, for 12 days. Thus thirty-three grams of dry mycelia was obtained per one liter of medium.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.147-154
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• 1984

Two Fe-hydrous oxide A,B and one Al-hydroxide minerals were synthesized precipitating Fe $Cl_3$ and $AlCl_3$ with alkali solution(NaOH) at pH 6.0, 12.0 and 4.5 respectively, for precise understanding of physico-chemical and surface charge characteristics of soils in which these minerals are dominant. Identification of these final products, effect of free and amorphous materials on X-ray diffraction analysis, particle size distribution and surface change characterics of these minerals were performed. Fe-hydroxide A and B were identified as great deal of X-ray amorphous material and as goethite with large amount of X-ray amorphous material, respectively. Dehydration by oven at $105^{\circ}C$ of these minerals exhibited akaganeite peaks with low X-ray amorphous hump and pure goethite peaks for Fe-hydroxide A and B, respectively. Both minerals, however, turned into hematite upon firing at $550^{\circ}C$. On the other hand, Al-hydroxide identified as mixture of gibbsite and bayerite of around 7:3 ratio. Application of sodium dithionite and ammonium oxalate solutions for removal of free or amorphous Fe and Al from these minerals revealed that only peak intensities of Al-hydroxide system were enhanced upon Al-extraction by oxalate solution even though dithionite solution was much powerful to extract Fe from Fe-hydrous oxide systems. Original(wet) Fe-hydrous oxide A has the highest specific surface and surface charge development(negative and positive), and the greatest amount of less than $2{\mu}m$ sized particles. Specific surface and clay sized particles(less than $2{\mu}m$) of Fe-hydrous oxide A, however, were drastically reduced upon dehydration($P_2O_5$ and oven drying) compare to the rest minerals. The Z.P.C. of these synthetic minerals were 8.0-8.5, 7.5-8.0 and 5.5-6.0 for Fe-hydrous oxide A, B and Al-hydroxide, respectively.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.2
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• pp.150-157
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• 2002

Purpose: As the incidence of non-typhoidal salmonella strains resistant to antibiotics has been increased, we attempted to investigate clinical aspects of non-typhoidal salmonella gastroenteritis and antibiotics resistance. Methods: From January 2000 to June 2002, 99 children with positive stool culture of non-typhoidal salmonella were studied about clinical features, the incidence of antibiotics and multi-drug resistance and the difference of incidence of antibiotics resistance according to immune status. Results: There were 66 males and 33 females. The majority of them were under 5 years of age (71%). 25 children were immunocompromised due to chemotherapy, steroid or immunosuppressive treatment. Serogroup D was the most common isolates (65%) followed by B (16%), C (8%) and E (8%). Resistance rate of 30% to ampicillin, 12% to chloramphenicol, 20% to trimethoprim-sulfamethoxazole (TMP-SMX), 11% to cefotaxime and 8% to cefixime were obtained. All isolates were susceptible to ciprofloxacine. Resistance rate to cefotaxime and cefixime in immunocompromised patients was 24% and 14.3% respectively, which were significantly higher compared to that in immunocompetent patients (6.8%, 5.6%, p<0.05). 11 isolates were resistant to three or more antibiotics. The incidence of multi-drug resistant isolates was significantly higher in immunocompromised patients (24%) than that of immunocompetent patients (6.8%). Conclusion: Because of the high prevalence of non-typhoidal salmonella strains resistant to ampicillin, chloramphenicol and TMP-SMX, third-generation cephalosporin might be the treatment of choice in non-typhoidal salmonella gastroenteritis. In particular, antibiotics should be carefully selected in immunocompromised patients because non-typhoidal salmonellas from them showed the higher incidence of antibiotic resistance and multi-drug resistance.

• Pediatric Infection and Vaccine
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• v.24 no.2
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• pp.79-86
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• 2017

Purpose: This study was aimed at analyzing the serotypes of group B streptococcus (GBS) isolated from Korean infants with invasive disease and evaluating their association with disease manifestation. Methods: Data were retrospectively collected from invasive GBS infections at Gachon University Gil Medical Center from January 2006 to June 2012 and at Samsung Medical Center from April 2010 to November 2012. Serotypes were determined by slide agglutination test. Results: A total of 37 cases were identified, which included 22 full-term infants and 15 preterm infants. Fifteen cases (40.5%) were early-onset, 19 (51.4%) was late-onset, and three (8.1%) was very late-onset. Early-onset diseases among preterm infants were higher than those among full-term infants (60.0% [9/15] vs. 27.3% [6/22], P=0.17). The most common manifestation was bacteremia (70.3%), followed by meningitis and septic arthritis. Among 24 isolates retrievable for serotyping, serotype III (41.7%) was most common, followed by V (16.7%), Ia, Ib, and II (12.5%, respectively), and non-typeable (4.2%). Serotype III was more common in isolates from full-term infants (10/22) than from preterm infants (0/15), whereas serotype V was more common in isolates from preterm infants (4/15) than from full-term infants (0/22) (P=0.002). No penicillin-resistant strain was detected, and resistance to erythromycin and clindamycin were both 64.9%. Conclusions: GBS is an important pathogen in both preterm and full-term infants, and serotype distribution of GBS causing invasive diseases can differ between preterm and full-term infants. It is necessary to monitor the nationwide epidemiology of GBS diseases, including in preterm infants, in order to prepare preventive measures without underestimating early-onset diseases.

• Childhood Kidney Diseases
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• v.14 no.1
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• pp.62-70
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• 2010

Purpose : The voiding cystourethrogram (VCUG) is the investigation of choice in detecting the vesicoureteral reflux in urinary tract infections in children. As it is a potentially distressing and invasive test, most of the parents are so concerned about the child's stress. In this study, we compared the difference of the state of anxiety of parents before and after the VCUG. Methods : We divided 68 parents whose children underwent VCUG into 2 groups; who have given an explanation about VCUG in detail using pictures (group 1) Vs. who have given an oral explanation only (group 2). All the parents submitted the same questionnaire 2 times before and after the VCUG, which consisted of State-Trait-Anxiety-Inventory X-I (STAI-X-I) and visual analog scale (VAS) on the perception of worry, anxiety, confusion and pain. Results : Before VCUG, the perception of pain was higher in group 1 (P<0.05). After VCUG, the anxiety and confusion were significantly higher in group 2 than group 1 (P<0.05). In group 1, STAI-X-I scores, the perception of worry and anxiety were significantly decreased after the VCUG (P<0.05). In group 2, the confusion and pain were increased after VCUG (P<0.05). Conclusion : It showed that doctor's explanation on the procedure in advance may raise the perception of pain and the possibility of refusal by parents. But the STAI-X-I, worry, anxiety after VCUG were significantly decreased in group 1, while the confusion and pain were increased in group 2. Therefore we suggest that prior and sufficient explanation about invasive procedure like VCUG can be helpful in ameliorating the anxiety of the parents.

• Journal of Life Science
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• v.18 no.4
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• pp.530-536
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• 2008

To investigate the molecular mechanism of the airway inflammation by Pseudomonas fluorescens, effects on the inflammatory mediators such as interleukin-8 (IL-8), cyclooxygenase-2 (COX-2), macophage inhibitory cytokine 1 (MIC-1) were assessed in the human alveolar epithelial cells. Exposure to P. fluorescens and its recombinant bacteria suppressed cellular viability in the A549 epithelial cells and pro-inflammatory cytokine interleukin-8 production. However, pro-inflammatory prostaglandin-producing COX-2 protein was not altered by P. fluorescens though its mRNA was slightly elevated. As the inhibitory cytokine for the pro-inflammatory mediators, MIC-1 expression was monitored in A549 cells. MIC-1 gene induction was not significantly enhanced but the protein processing was changed by exposure to P. fluorescens. Pro-protein form of MIC-1 (${\sim}40\;kD$) was cleaved into active form mature MIC-1 (${\sim}15\;kD$) and propeptide (${\sim}28\;kD$) by the bacteria exposure. MIC-1 activation can contribute to the suppression of cellular viability by P. fluorescens and can retard IL-8-induced monocyte recruitment. However, sustained activation of MIC-1 can mediate the tissue injury by P. fluorescens exposure.

• The Korean Journal of Nuclear Medicine
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• v.39 no.1
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• pp.26-33
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• 2005

Purpose: The purpose of this study is to evaluate migration of technetium-99m hexamethylpropylene amine oxime ($^{99m}Tc$-HMPAO) labeled immature and mature dendritic cells (DC) in the mouse. Methods: DC were collected from bone marrow (BM) of tibiae and femurs of mice. Immature and mature DC from BM cells were radiolabeled with $^{99m}Tc$-HMPAO. To evaluate the functional and phenotypic changes of DC from radiolabeling, the allogeneic mixed lymphocyte reaction (MLR) and fluorescence-activated cell sorting (FACS) analysis were performed before and after labeling with $^{99m}Tc$-HMPAO. Migration of intravenously injected DC (iv-DC) was assessed by serial gamma camera images of mice with or without subcutaneous tumor. Percent injected dose per gram (%ID/g) was calculated in lungs, liver, spleen, kidneys, and tumor through dissection of each mice after 24 hours of injection. Results: Labeling efficiency of immature and mature DC were $60.4{\pm}5.4%\;and\;61.8{\pm}6.7%$, respectively. Iv-DC initially appeared in the lungs, then redistributed mainly to liver and spleen. Migration of mature DC to spleen was significantly higher than that of immature DC ($38.3{\pm}4.0%\;vs.\;32.2{\pm}4.1%$ in control group, $40.4{\pm}4.1%\;vs.\;35.9{\pm}3.8%$ in tumor group; p<0.05). Migration to tumor was also significantly higher in mature DC than in immature DC ($2.4{\pm}0.3%\;vs\;1.7{\pm}0.2%$; p=0.034). Conclusion: Assessment of migration pattern of DC in mice was possible using $^{99m}Tc$-HMPAO labeled immature and mature DC. Migration of mature DC to spleen and tumor was higher than that of immature DC when they were i.v. injected.

• The Korean Journal of Nuclear Medicine
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• v.36 no.6
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• pp.325-332
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• 2002

Purpose: Human Na+/I- symporter (hNIS) is known to be expressed in many tissues other than thyroid gland. The breast cancer cells are one of them and the possibility of radioiodine therapy in treatment of the breast cancer may be suggested. We investigated the expression rate of hNIS and the relationship between the expression of hNIS and the finding of 99mTc-MIBI scintimammographv in the breast cancer Materials and Methods: Surgically proved 56 patients with breast cancer were the subjects of this study The expression of hNIS were evaluated by immunohistochemistry and the results were compared to the findings of 99m7c-MIBI scintimammography. Results: Overall expression rate of hNIS was 41.1% in 56 patients. According to the pathologic diagnosis, it was 42.9% in 49 patients with invasive ductal carcinoma and 28.6% in the 7 patients with ductal carcinoma in situ. The expression rate of hNIS in the 41 cases with a focal increased uptake at he breast lesion on 99m7c-MIBI sointimammogram was 31.7%. That in the 15 cases without any abnormal uptake on the scan was significantly higher(65.7%, p<0.05). Conclusion: The expression rate of hNIS in the patients with breast cancer was not so high. The rate was higher in the patients with no increased uptake at the breast lesion on 99m7c-MIBI scintimammography.

• The Korean Journal of Nuclear Medicine
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• v.34 no.4
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• pp.303-311
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• 2000

Purpose: Thallium behaves similarly to potassium in vivo. Potassium channel opener (K-opener) opens ATP-sensitive $K^+$-channel located at cell membrane, resulting in potassium efflux from cytosol. We have previously reported that K-opener can alter biokinetics of Tl-201 in cultured cells and in vivo. Malignant tumor cells have high Na-K ATPase activity due to increased metabolic activities and dedifferentiation, and differential delineation of malignant tumor can be possible with Tl-201 imaging. K-opener may affect tumoral uptake of Tl-201 in vivo. To investigate the effects of pinacidil (one of the potent K-openers) on the localization of the tumor with Tl-201 chloride, we evaluated the changes in biodistribution of Tl-201 with pinacidil treatment in tumor-bearing mice. Materials and Methods: Baltic mice received subcutaneous implantation of murine breast cancer cells in the thigh and were used for biodistribution study 3 weeks later. $100{\mu}g$ of pinacidil dissolved in $200{\mu}l$ DMSO/PBS solution was injected intravenously via tail vein at 10 min after 185 KBq ($5{\mu}Ci$) Tl-201 injection. Percentage organ uptake and whole body retention ratio of Tl-201 were measured at various periods after injection, and values were compared between control and pinacidil-treated mice. Results: Pinacidil treatment resulted in mild decrease in blood levels of Tl-201, but renal uptakes were markedly decreased at 30-min, 1- and 2-hour, compared to control group. Hepatic, intestinal and muscular uptake were not different. Absolute percentage uptake and tumor to blood ratios of Tl-201 were lower in pinacidil treated mice than in the control group at all time points measured. Whole body retention ratio of Tl-201 was lower in pinacidil treated mice ($58{\pm}4%$ ), than in the control group ($67{\pm}3%$) at 24 hours after with injection of $100{\mu}g$ pinacidil. Conclusion: K-opener did not enhance, but rather decreased absolute tumoral uptake and tumor-to-blood ratios of Tl-201. Decreased whole body retention ratio and renal uptake were observed with pinacidil treatment in tumor-bearing mice.