• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.10-15
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• 2010

Most pesticides are poorly soluble in water and must be dissolved in a solvent carrier before being added to the test medium on aquatic toxicity test. The concentration of solvent is critical to the success of a test. This study were conducted to recommend possible organic solvents which have good solubility for pesticides and low toxicity to Korean native water flea to establish new standard toxicity test methods using Korean native water flea for ecological risk assessment of pesticide. Four Korean freshwater cladocerans, Daphnia obtusa, Daphnia sp., Moina macrocopa and Simocephalus vetulus were exposed to 10 different organic solvents during 48 hours to evaluate their toxic response to solvents. Ethyl acetate was the most toxic to cladocerans tested. Although ethyl ether was the least toxic to cladocerans tested, it may not adequate as possible solvent in aquatic toxicity test due to high volatility and low water solubility. In conclusion, acetone, methanol, ethanol and acetonitrile which has low toxicity as well as good water solubility are recommended as optimal organic solvent to use in aquatic toxicity tests with Korean native cladocerans tested.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.2
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• pp.135-144
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• 2010

Purpose: The purpose of this study is that through production of phantom for respiration gated radiotherapy, assessing appropriacy of exposure dose for the therapy using RPM (Real-time Position Management). Materials and Methods: We located measurement object on the phantom for respiration gated radiotherapy made of 2 linear actuator, acrylic panel, stanchion, iron plate ets. to drive (up, down, front, back). Using 4D CT scan, we analyzed patient's respiration and reproduced the movement by computer. On the phantom, we located a 2D-Array (PTW) and an White water phantom (4.5 cm) and used DMLC (interval 2 cm) in the field size $10{\times}10\;cm$, then exposed 21EX X-ray 100 MU, in the case of phantom was (1) static (2) moving (3) gated using RPM respectively gantry $0^{\circ}$ and $90^{\circ}$ We measured with a 0.125 CC ionization chamber (PTW) on the phantom (7.5 cm) in the same condition. Results: Ionization chamber: There were within 0.3% of error with gating respiration and approximately 2% of error without gating in the same condition. 2D-Array: Gantry $90^{\circ}$, field size $10{\times}10\;cm$, using DMLC. There were within 3% of error with gating respiration and approximately 16% of error without gating. Conclusion: The phantom for respiration gated radiotherapy makes plans considering patient's movement, quantitative analysis of exposure dose and proper assessment therapy for IMRT patients using RPM possible.

• Applied Microscopy
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• v.40 no.4
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• pp.193-200
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• 2010

This experiment was performed to evaluate the morphological responses of the duodenal epithelial cells of the mouse, inoculated with Ehrlich carcinoma cells in the inguinal area, following administration of Bacillus Calmette-Guerin (BCG). In the experimental groups, each mouse was inoculated with $1{\times}10^7$ Ehrlich carcinoma cells subcutaneously in the inguinal area. From next day after inoculations, 0.2 mL of saline or BCG (0.5 mL/25 g B.W.: $0.03{\times}10^8\sim0.32{\times}10^8$ CFU) were injected subcutaneously to the animals every other day, respectively. The day following the 7th injection of saline or BCG, each mouse was injected with a single dose of $0.7{\mu}Ci$/g of methyl-$^3H$-thymidine (25 Ci/mmol, Amersham Lab, England) through tail vein. Seventy minutes after the thymidine injection, animals were sacrificed, and duodenal tissues were taken and fixed in 10% neutral formalin. Deparaffinized sections were coated with autoradiographic emulsion EM-1 (Amersham Lab, England) in a dark room and dried and were placed in a light-tight box. The number of labeled epithelial cells in the duodenal mucosae (mean number of labeled epithelial cells per 3.5 mm length of mucosa) were observed and calculated. On the light microscopic study, duodenal mucosae had no severe morphological changes following the injection of BCG. In the tumor control and BCG treated groups, a number of small lymphocytes and eosinophile leucocytes are slightly increased as compared with those of the normal control ones. On the autoradiographic study, number of the labeled cells of normal control, tumor control and BCG-treated mice were 632.3 (${\pm}14.47$), 761.7 (${\pm}27.65$) and 505.0 (${\pm}17.09$) respectively. From the above results, BCG may suppress the DNA synthesis of the duodenal epithelial cells, but does not results severe structural defect on the duodenal mucosae. And it is suggested that BCG may greatly improve the anticancer therapy on certain kind of cancer.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.1
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• pp.36-43
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• 2010

Purpose: The aim of this study was to evaluate the clinical features and factors contributing to treatment outcome for chronic functional constipation in children. Methods: We analyzed the medical records of patients with constipation, who visited the inpatient or outpatient clinic of the Department of Pediatrics of Pusan National University Hospital, between January 1998 and December 2007. The clinical features, outcomes, and factors affecting the treatment response according to the main drug (lactulose vs. PEG 4000) were analyzed retrospectively. Results: Two hundred forty children (142 males and 98 females) were enrolled in this study. The mean age was 51.2${\pm}$37.9 months. The duration of symptoms was 32.6${\pm}$33.7 months. The accompanying symptoms were as follows: encopresis, 91 (30.4%); abdominal pain, 76 (31.6%); and blood-tinged stool, 37 (15.4%). The treatment response was achieved earlier in females (p<0.001), patients with accompanying symptoms (p<0.05), and patients treated with PEG 4000 (p=0.001). The duration of symptoms (p<0.05) and stool frequency before treatment (p<0.05) were related to a delayed treatment response. Relapse occurred in 7 children, all of whom were treated successfully later. Conclusion: Factors contributing to treatment response are female gender, accompanying symptoms, duration of symptoms, and stool frequency before treatment. PEG 4000 is superior to lactulose in response time and taken into consideration as a primary drug for the treatment of functional constipation of children. Early treatment and sufficient treatment time may also be important factors to achieve an early response and prevent relapse.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.1
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• pp.23-29
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• 2010

Purpose: The aim of this study was to assess the benefits of routine pre-endoscopy coagulation screening tests and platelet counts in Korean children. Methods: Between March 2004 and December 2009, children who underwent gastrointestinal endoscopy for the evaluation of various gastrointestinal symptoms were included. All of the subjects included in the study also underwent routine coagulation screening and platelet count determinations prior to endoscopy and biopsy. The clinical records and laboratory tests were retrospectively reviewed in all patients. Results: One hundred sixty-two of 1,476 (11%) patients who underwent endoscopy had abnormal results on pre-screening coagulation tests. Fourteen patients underwent coagulation factor assays due to abnormal clotting results in consecutive tests or due to clinical evidence of a bleeding tendency. Seven patients were diagnosed with factor XII deficiency, one patient was diagnosed with von Willebrand disease, one patient had von Willebrand disease and factor XII deficiency, and one patient was presumed to have mild hemophilia. The remaining 4 patients had normal results with the factor assays. The results of platelet counts were normal with the exception of 1 patient. No patient had significant bleeding during the endoscopic procedures, despite abnormal pre-endoscopic coagulation tests. Conclusion: Routine coagulation screening tests and platelet counts revealed abnormal results in some patients. Most of the patients with abnormal clotting were shown to have a factor XII deficiency, which had no significant associated bleeding tendencies; the other patients were diagnosed with hemophilia or von Willebrand disease. Therefore, although abnormal pre-endoscopic coagulation is not always related to significant bleeding complications, pre-endoscopic coagulation screening may be useful in some children in predicting the risk of bleeding tendency during endoscopic procedures.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.1
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• pp.7-22
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• 2010

Purpose: Nodular gastritis is a characteristic finding of Helicobacter pylori infection in children. The aim of this study was to evaluate the difference in gene expression in the gastric mucosa of H. pylori-infected and non-infected children, and to analyze the difference in gene expression using cDNA microarray analysis of nodular gastritis caused by H. pylori infection. Methods: Twelve children (6 boys and 6 girls; mean age 9.8 years) who underwent upper gastrointestinal endoscopy and biopsy at Seoul National University Bundang Hospital were included in the study. The subjects were divided into three groups according to the presence of H. pylori infection and nodular gastritis on endoscopic examination. Gastric mucosa tissue was kept at $-70^{\circ}C$ and RNA was extracted to perform cDNA microarray analysis in each patient. Results: cDNA microarray analysis in children revealed a clear distinction between H. pylori-infected and non-infected gastric mucosa. Specifically, 182 over-expressed genes and 29 under-expressed genes were identified in H. pylori-infected gastric mucosa compared to non-infected mucosa. H. pylori-infected nodular gastritis revealed different gene expression patterns from H. pylori-infected normal gastric mucosa; five genes were over-expressed and five genes were under-expressed. Conclusion: In the presence of H. pylori infection, gastric mucosa shows distinct differences in gene expression, and nodular gastritis with H. pylori infection in children may be associated with over- or under-expression of some genes. Further studies are required to clarify the host response and the pathogenesis of nodular gastritis in children.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.12 no.1
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• pp.14-22
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• 2012

Objectives: This study was performed to review clinical manifestations of hyperphenylalaninemia patients in Korean. Methods: 178 cases of hyperphenyalaninemia were diagnosed at department of pediatrics, Soonchunhyang University Hospital from January, 1983 to August. We reviewed DNA analysis, MR imaging, EEG, radiography of the left hand and wrist, bone densitometry (BMD), IQ test of hyperphenyalaninemia patients. Results: Out of 178 cases, 161 cases were diagnosed classic phenylketonuria and 17 cases were diagnosed BH4 deficiency. 122 cases performed DNA analysis. R243Q (10.3%), Y204C (9.9%), and IVS4-1G>A (8.1%) mutations were predominant. 22 cases underwent MR imaging. Varying degrees of symmetrical high signal intensity were noted on T2-weighted sequences in the periventricular deep white matter of 15 cases. 23 cases were performed EEG. 12 cases (52.3%) showed abnormal pattern. EEG abnormalities showed in 11 cases. On lumbar BMD four of 11 cases (36%) showed reduced bone density of more than 1 S.D. in four of 11 cases, bone age was less than chronological age by at least one year. 18 cases were performed IQ test. Mean IQ scores was $84{\pm}21.6$. Among older than 15 years (9 cases), Mean IQ scores was $72{\pm}21.2$. PTPS deficiency was 14 cases, DHPR deficiency was 2 cases, and GTPCH deficiency was 1 case. Conclusion: We confirmed there were varieties of DNA mutations. And MR imaging and EEG were nonspecific in PKU patients. Older children showed lower IQ score. Low phenylalanine diet prevents brain damage in PKU patient. Not only first few years of life but also lifetime, Keeping low phenylalanine diet is important.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.269-277
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• 2010

Selenium is an essential micronutrient for normal body function and functions as an essential constituent of selenoproteins. This study was carried out to investigate effect of selenium on the formation of colonic aberrant crypt foci (ACF) and tumor formation in a mouse model. Five-week old ICR mice were acclimated for one week and fed different selenium diet (0.02, 0.1, and 0.5 ppm) for 12 weeks. Animals received three intraperitoneal injections of azoxymethane (10 mg/kg B.W. in saline for 3 weeks), followed by 2% dextran sodium sulfate in the drinking water for a week. There were four experimental groups, including a normal control group and three different selenium levels groups. After sacrifice, the total numbers of aberrant crypt (AC) and ACF were measured in the colonic mucosa after methylene blue staining. The number of tumors was noted for tumor incidence. Liver selenium concentration was measured using ICP-AES method. Gutathione peroxidase (GPx) activity was determined using a GPx assay kit in the liver and colon. TUNEL assay and proliferating cell nuclear antigen (PCNA) staining were performed to examine the cell apoptosis and cell proliferation, respectively. Immunohistochemistry of $\beta$-catenin was also performed on the mucous membrane tissue of colon. The activity of GPx in the liver and colon was decreased in the selenium-deficient diet group while it was increased in the selenium-overloaded diet group. Apoptotic positive cells were increased in the selenium-overloaded diet group but decreased in the selenium-deficient diet group. PCNA staining area was decreased in the selenium-overloaded diet group. In addition, the $\beta$-catenin protein level in the selenium-deficient diet group was increased but decreased in the selenium-overloaded diet group. These results indicate that dietary selenium might exert a modulating effect on colon cancer by inhibiting the development of ACF and colon tumor formation in this mouse model.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.251-257
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• 2010

The experiment was conducted to find out the nutritive value and microbial status of different wholesale cuts of goat carcass. The meat sample (4 cuts from each animal $\times$ 3 different age groups $\times$ 3 animals in each group = 36 samples) was obtained from 1-, 2-, and 3-year aged goats. The whole sale cuts were shoulder, rack, loin and leg of each goat carcass. To assess the quality of meat sample, the general appearance, color, smell, juiciness, proximate composition, pH, total bacteria, coliform bacteria, and yeast were studied. The mean pH value of different cuts ranges from 5.65-5.69 didn't differ significantly, but due to age differences the pH values (5.59-5.74) differed significantly (p < 0.01). The values of juiciness in different ages ranged from 32.24-42.10% which differed significantly (p < 0.01). The marbling of the cuts of rack portion was more pronounced than that of other cuts. The ranges of crude protein (CP) content of goat carcass (20.78-27.71%) differed significantly (p < 0.01) and leg portion contained higher CP than other portion. Fat contents of different cuts ranged from 2.66-11.47% differed significantly (P < 0.01). The moisture content of the carcass differed significantly which ranged from 69.20-73.31%. The ash content of the cuts of 1-year aged groups (0.99 $\pm$ 0.13%) was higher than that of other age groups and differed significantly (P < 0.01). The calcium (Ca) content did not differ significantly. The phosphorus (P) content was higher in one year old goat (0.15 $\pm$ 0.03%) than that of the goats of other ages. The total viable count (TVC) content of microorganisms ranging from 5.05-5.15 log cfu/g at different ages did not differ significantly. The coliform count (CC) of different cuts differed significantly (P < 0.01) which ranged from 2.56-3.05 log cfu/g; it also differed significantly (P < 0.05) in different ages (2.79-2.84 log cfu/g) and was higher in 1 year old goat carcass. The yeast count differed significantly in different cuts (P < 0.01) and ages (P < 0.05). From the study it is concluded that the age and different wholesale cuts have direct influence on quality of goat carcass.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.335-345
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• 2010

The objective of this study was to model the kinetics of S. aureus survival on high risk foods in school foodservice operations. After inoculating S. aureus ATCC25923 onto the various high risk foods, the effects of competitive microorganism, storage temperatures($25^{\circ}C$, $35^{\circ}C$), and initial contamination levels ($1.0{\times}10^2\;CFU/g$, $1.0{\times}10^5\;CFU/g$) on the growth of S. aureus were investigated. Lag time decreased and specific growth rate increased with a storage temperature ($25^{\circ}C$<$35^{\circ}C$) and with a higher initial inoculation level ($1.0{\times}10^2\;CFU/g$<$1.0{\times}10^5\;CFU/g$). Previously it was shown that S. aureus is a weaker competitor than other organisms, but it proliferates aggressively in a noncompetitive environment. However, in our study, when S. aureus was used to inoculate japchae (glass noodles with sauteed vegetables) and meat ball, the growth of S. aureus was similar and more active with competitive organisms than that without competitive organisms. Regardless of other factors, the initial level of S. aureus was a more significant factor of the growth. High inoculation levels of S. aureus were reached at 6 log CFU/g within 3 hours. An incubation temperature of $35^{\circ}C$ and the animal protein component of menu items also were identified as significant factors influencing the growth of S. aureus. Therefore, the duration of time meals are stored before serving should be considered a critical control point. Food service providers must control time and temperature to insure the safety of cooked foods.