• Korean Journal of Bronchoesophagology
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• v.15 no.2
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• pp.36-41
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• 2009

Background : Controversy exists whether patients with esophageal carcinoma are best managed with classical Ivor Lewis esophagectomy(ILO) as combined thoracic and abdominal approach or transhiatal esophagectomy(THO). The THO approach is known to be superior with respect to operative time, morbidity and mortality, and length of stay, especially at poor pulmonary function patient, but may represent an inferior cancer operation due to inadequate mediastinal clearance compared with ILO. Accordingly, we estimated the THO role at esophageal cancer to compare each operative approach. Material and Method : From January 2002 to December 2007, we performed a retrospective review of all esophagectomies performed at Keimyung University Dongsan Medical Center; 36 underwent THO, and 11 underwent ILO. Result : There were all men and squamous cell carcinoma but 1 woman at ILO group, 2 women at THO group. There were no significant differences between THO and ILO with age, sex, location of tumor, mean tumor length. There were significant differences at preoperative pulmonary function test(In ILO group, average FEV1 is $2.65{\pm}0.6\;L/min$ and iIn THO group, average FEV1 is $2.07{\pm}0.7\;L/min$). The amount of blood transfusion, hospital stay, leak rates and respiratory complication, hospital mortality rate were not significantly different. Conclusion : There was no significant difference in the post-operative complication, hospital mortality rate, long-term survival of patients of both operative method. THO method had lower mobidity and mortality at poor pulmonary function patient than ILO method. Hence, THO is a valid alternative to ILO for patients with poor general condition or expected post-operative respiratory complication.

• YAKHAK HOEJI
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• v.45 no.5
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• pp.536-544
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• 2001

increase the viability of oral typhoid vaccine during the passage through the castro-intes-tidal tract, numerous attempts have been made including the vaccine coating. However problems such as high death rate during the coating process and its instability in the gastric juice still remain to be solved. In this study, the oral vaccine was made as the micro-enteric beads by adding Salmomella typhi Ty21a cells to sodium alginate solution and spraying onto calcium chloride solution (ionotropic relation method). The vaccine showed more than 90% of its original viability after treating it for 1 hour in the artificial gastric juice (37$^{\circ}C$, 300 rpm). The clearance rate of the Ty21a in the liver and spleen of the mice orally administrated with coated Ty21a was similar to that of the mice intraperitoneally administrated with uncoated Ty21a. The peripheral blood lymphocytes (PBL) isolated from the mice orally administered with this vaccine produced 15.5 fold higher specific IgA antibody titer than that from the control mice administerd with saline solution. furthermore, the mice treated with the coated Ty21a had higher survival rates (50~87%) than the control mice treated with saline solution (0~10%) in the intraperitoneal challenge test with wild type S. typhi Ty21a cells. These results suggest that the alginate-based coating technique is effective to protect live Ty21a from acidic environments, and produces better intestinal immune responses thereby providing a potentially excellent oral typhoid vaccine.

• Journal of the Korean Society of Safety
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• v.36 no.5
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• pp.10-17
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• 2021

The controversy over the risk of the human body being affected by electromagnetic fields emitted from 60 Hz power lines continues without end. There are currently no new studies or research progress being made in this direction that is notable, and the number of civil complaints is gradually increasing. The problem is that each study produces different results, among which the effect of exposure to magnetic fields on childhood leukemia is a major one. In Korea, an electrician who was maintaining a 22.9 kV power line died of leukemia, which has recently been recognized as an occupational disease. Methods to reduce magnetic fields from power lines include shielding with wire loops, incorporating split phases and compaction techniques, installing underground power lines, converting to high-voltage direct current (HVDC), and increasing the ground clearance of transmission towers. Depending on whether a separate power supply is needed or not, there are two types of wire loops: passive loop and active loop. Magnetic field reduction is currently done through underground power lines; however, the disadvantage of this process is high construction costs. Installing passive loops, with relatively low construction costs, leads to lower magnetic field reduction rates than installing underground cables and a weakness to not solving the landscape problem. This methodological study aims at designing methods and reducing the effects of 2-wire set loops-the simplest and most practical. Since the method proposed in this study has been designed after analyzing the distribution of complex electromagnetic fields near the expected loop installation location, a practical design can be implemented without the need for any difficult optimization programming.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.2
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• pp.217-225
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• 2019

Objectives: The aim of this study is to evaluate the quality management systems of domestic asbestos survey and monitoring service providers and the relationships with the number of licenses or designations and sales performances. Methods: Data on quality management systems were collected by assessors who were assigned by the Korea Occupational Safety and Health Agency(KOSHA) during a pilot evaluation program for designated asbestos survey and monitoring service providers in 2016 using evaluation criteria developed by KOSHA. Basic characteristics, evaluated scores, and sales performance were gathered and statistically analyzed. Results: The median and arithmetic mean of the total scores were 0.64 and 0.66. Evaluation fields that scored highly with the highest percentages were sales performance, installation and availability of equipment, compliance with the mandatory minimum number of airborne samples, laboratory independence, and results of proficiency analytical testing, in that order. Evaluation fields that received low marks with the highest percentages were the training of personnel, blank field samples, calibration of flow rates, preliminary check and visual inspection of the work area prior to the clearance test, and review and approval of final reports, in that order. Comparison of normalized scores between service providers registered for asbestos and other tasks and those designated for only asbestos showed significant differences in their evaluated scores. Sales performance did not show a positive correlation with evaluated scores. Conclusions: The quality management systems of domestic asbestos survey and monitoring service providers were poor. High scores were recorded mostly in evaluation fields related to regulatory requirements. Low scores were recorded mostly in evaluation fields related to documentation and recordkeeping. Considering the low influence of quality on sales performance, the government needs to evaluate the quality management of asbestos survey and monitoring service providers and provide the results to public in order to address their low levels of quality management.

• Asia-Pacific Journal of Business
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• v.11 no.1
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• pp.145-165
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• 2020

Purpose - The purpose of this study is to suggest strategies and solutions for entering China in the tariff and non-tariff sectors of the cosmetic industry. Design/methodology/approach - This study analyzed the import tariff rate of cosmetics in China, and analyzed the export cost by actually interviewing the exporting companies to derive the economic effect of non-tariff measures. Findings - First, We proposed the use of the FTA business model (basic cosmetics), the use of Korea-China FTA tariffs (foam cleansing, toothpaste), and the use of APTA tariffs (perfume). Second, We proposed cooperation between the governments to facilitate customs clearance procedures and improvement of FTA awareness among corporate practitioners. Third, We proposed the expansion and support of the AEO MRA system and the expansion of Korea-China MOU conclusions regarding the certification system, and the international standardization of domestic licensing system and technical conditions. Fourth, We proposed the use of government-supported projects related to obtaining overseas certifications and overseas expansion through collaboration with the same industry. Research implications or Originality - HS3304 products excluded from the Korea-China FTA should take full advantage of the FTA business model. In addition, the non-tariff measure costs are fixed costs per year, so the ratio decreases as the number of exports and export volume increases.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.347-355
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• 2006

A study was conducted to predict the rumen microbial protein production based on urinary excretion of purine derivatives in buffaloes fed a diet of wheat straw and concentrate (40:60) at four fixed levels of feed intake. (95, 80, 60 and 40% of preliminary voluntary feed intake) following experimental protocol of IAEA (Phase I). The buffaloes were allocated according to a $4{\times}4$ latin square design. The urinary allantoin, uric acid, total PD excretion (mmol/d) in treatments L-95, L-80, L-60 and L-40 was 20.13, 16.00, 12.96 and 9.17; 1.88, 2.12, 2.11 and 2.15; 22.01, 18.12, 15.07 and 11.32, respectively and were significantly (p<0.05) different among treatments except for uric acid. The rate of PD excretion (mmol/d) was positively correlated with the digestible organic matter intake. Variations were observed in PD and creatinine concentration in spot samples collected at 6-hour interval. However, daily PD:Creatinine ratio (PDC index) appears to be a reasonably good predictor of microbial-N supply. The contribution of basal purine excretion to total excretion of purine derivatives (PD) was determined in pre-fasting period followed by a fasting period of 6 d (Phase II). Daily PD and creatinine excretion (mmol/kg $W^{0.75}$) during fasting averaged 0.117 and 0.456 respectively for buffaloes. The excretion rates of PD decreased significantly (p<0.01) during fasting compare to pre-fasting period, the urinary creatinine excretion remained almost similar. Except for creatinine, plasma concentration of target parameters significantly (p<0.01) declined during fasting. Likewise, glomerular filtration rate (GFR) and renal clearance of allantoin and uric acid also decreased. Based on the PD excretion rates during fasting and at different levels of feed intake obtained in this study, a relationship between daily urinary PD excretion (Y-mmol) and microbial purine absorption (X-mmol) was developed for buffaloes as Y = 0.74X+0.117 kg $W^{0.75}$. The microbial N supply (g/kg DOMI) remained statistically similar irrespective of dietary treatment. The results showed that excretion of urinary purine derivatives is positively correlated with the levels of feed intake in Murrah buffaloes and thus, estimation of urinary purine derivatives and PDC index could be used to determine microbial nitrogen supply when there is large variation in level of feed intake.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.2
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• pp.130-136
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• 2008

Purpose: Lamivudine is known to be effective for the treatment of chronic hepatitis B in adults. However, data on lamivudine therapy in pediatrics is limited. The aim of this study was to evaluate the efficacy and durability of lamivudine therapy for chronic hepatitis B in Korean children. Methods: A total of 44 children (27 males and 17 females, ages 6 months to 14.8 years, mean age 6.7 years) with chronic hepatitis B who received lamivudine (3 mg/kg/day, max 100 mg) for at least 12 months were enrolled. We evaluated the serum AST, ALT and serological HBV markers (HBsAg and anti-HBs, HBeAg and anti HBe, and HBV DNA) periodically. Predictive three year cumulative seroconversion rates were obtained using the Kaplan-Meier method. Results: Twenty one (48%) of 44 children achieved seroconversion of HBeAg by three years, while 23 (42%) children did not. HBV DNA was cleared in 34 (77%) children and the serum ALT levels were normalized in 41 children (93%). The three year cumulative seroconversion rates were 60% for HBeAg, and the clearance rates were 76% for HBV DNA. Eighteen children who discontinued lamivudine after HBeAg seroconversion maintained the therapeutic response for three years (treatment duration 13~58 months mean 24 months). Viral breakthrough developed in 12 children (27%) during the therapy and the YMDD mutation was documented in 11 children (25%). The mean duration for the development of a mutation was 22.7 months. Loss of HBsAg occurred in 6 children (14%). The pretreatment ALT levels were higher in responders; however, the differences were not statistically significant (p>0.05). Conclusion: The results of this study showed that lamivudine treatment had a favorable effect and durable therapeutic response in children with chronic hepatitis B. Long term follow-up and alternative therapy are warranted for those patients who do not respond to this treatment.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.7 no.2
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• pp.197-207
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• 2004

Purpose: To evaluate the long-term therapeutic efficacy and durability of lamivudine in Korean children with chronic hepatitis B. Methods: A total of 48 children (31 male and 17 female; age, 1~18 years, mean, 8 years) with chronic hepatitis B who received lamivudine for at least six months from March 1999 to September 2004 were followed for a mean period of 29 months (8~66 months) at Department of Pediatrics, Kyungpook National University Hospital in Korea. Response to treatment was defined as the normalization of ALT and HBV DNA levels, and HBeAg seroconversion after the initiation of treatment. Results: Twenty nine (60%) among the 48 children treated with lamivudine responded and nine (19%) children lost HBsAg during therapy. ALT and HBV DNA level had normalized in 94% one year after the initiation of treatment. Kaplan-Meier estimates of cumulative HBeAg seroconversion rates over the years were 13% (0.5 year), 34% (1 year), 50% (1.5 years), 68% (2 years), 79% (2.5 years) and 90% at 3 years respectively. Above all, among the 22 children treated before the age of seven, loss of HBsAg occurred in eight (36%), which showed superior rate of HBsAg loss (p=0.002 vs age >7). Conclusion: Long-term treatment of lamivudine improved the rate of HBeAg seroconversion in Korean children with chronic hepatitis B. After three years' observation, most of treated children have sustained HBeAg clearance. We believe that lamivudine should be tried as the first therapeutic option for children with chronic hepatitis B in immune clearance phase.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.355-365
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• 2010

The aim of this study was to investigate the effect of supplemental recombinant bovine somatotropin (rbST) and cooling with misters and fans on renal function in relation to regulation of body fluids in different stages of lactation in crossbred Holstein cattle. Ten, 87.5% crossbred Holstein cattle were divided into two groups of 5 animals each, housing in a normal shaded barn (NS) and in a shaded barn with a mister-fans cooling system (MF). The experiment in each group was divided into 3 phases, early- (Day 75 postpartum), mid- (Day 135 postpartum), and late stage of lactation (Day 195 postpartum). The pre-treatment study was conducted on the starting day of each stage of lactation and the treatment study was performed after the end of the pre-treatment, during which the animal was injected with 500 mg of rbST (POSILAC) every 14 days for three times. During the study, ambient temperature at the hottest period daily in the MF barn was significantly lower, while relative humidity was higher than that of the NS barn. The temperature humidity index (THI) in both barns ranged from 79-85 throughout the periods of study. Cows in the MF barn showed a lower rectal temperature and respiration rate as compared with cows in the NS barn. The effect of rbST administration increased both rectal temperature and respiration rates of cows housed in either the NS or MF barn. Milk yield significantly increased in cows treated with rbST in all stages of lactation. Increases in mammary blood flow, accompanied by increases of total body water (TBW), extracellular fluid (ECF), blood volume (BV) and plasma volume (PV), were observed in both groups of cows receiving rbST in all stages of lactation. No alterations of renal blood flow and glomerular filtration rate were observed in cows receiving rbST, but decreases in urinary excretion and fractional excretion of sodium, potassium and chloride ions appeared to correlate with reduction in the rate of urine flow and osmolar clearance during rbST administration. These results suggest that the effect of rbST supplementation to cows housed either in NS or MF barns on body fluid volume expansion is attributable to changes in the rate of electrolyte excretion by the kidney. The increased availability of renal tubular reabsorption of sodium, potassium and chloride ions during rbST treatment was a major factor in retaining body water through its colligative properties in exerting formation of an osmotic force mechanism.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.1
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• pp.9-14
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• 2016

Objective: Autophagy contributes to the clearance and recycling of macromolecules and organelles in response to stress. We previously reported that vitrified mouse oocytes show acute increases in autophagy during warming. Herein, we investigate the potential role of Atg7 in oocyte vitrification by using an oocyte-specific deletion model of the Atg7 gene, a crucial upstream gene in the autophagic pathway. Methods: Oocyte-specific Atg7 deficient mice were generated by crossing Atg7 floxed mice and Zp3-Cre transgenic mice. The oocytes were vitrified-warmed and then subjected to in vitro fertilization and development. The rates of survival, fertilization, and development were assessed in the Atg7 deficient oocytes in comparison with the wildtype oocytes. Light chain 3 (LC3) immunofluorescence staining was performed to determine whether this method effectively evaluates the autophagy status of oocytes. Results: The survival rate of vitrified-warmed $Atg7^{f/f}$;Zp3-Cre ($Atg7^{d/d}$) metaphase II (MII) oocytes was not significantly different from that of the wildtype ($Atg7^{f/f}$) oocytes. Fertilization and development in the $Atg7^{d/d}$ oocytes were significantly lower than the $Atg7^{f/f}$ oocytes, comparable to the $Atg5^{d/d}$ oocytes previously described. Notably, the developmental rate improved slightly in vitrified-warmed $Atg7^{d/d}$ MII oocytes when compared to fresh $Atg7^{d/d}$ oocytes. LC3 immunofluorescence staining showed that this method can be reliably used to assess autophagic activation in oocytes. Conclusion: We confirmed that the LC3-positive signal is nearly absent in $Atg7^{d/d}$ oocytes. While autophagy is induced during the warming process after vitrification of MII oocytes, the Atg7 gene is not essential for survival of vitrified-warmed oocytes. Thus, induction of autophagy during warming of vitrified MII oocytes seems to be a natural response to manage cold or other cellular stresses.