• Journal of Chest Surgery
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• v.43 no.3
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• pp.235-245
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• 2010

Background: Our goal was to evaluate anti-calcification effects of decellularization and diverse fixing methods including preincubation of the bovine pericardium with ethanol. We also assessed changes in mechanical properties. Material and Method: Harvested bovine pericardium was decellularized with 0.25% sodim dodecysulfate and then treated with 5 methods of fixation: (1) 0.5% glutaraldehyde (GA) for 14 days, (2) 0.5% GA for 5 days, 2% GA for 2 days and 0.25% GA for 7 days, (3) 0.5% GA for 5 days, 2% GA for 2 days, 0.25% GA for 7 days, and then 70% ethanol for 2 days, (4) 0.5% GA for 5 days, a mixture of 2% GA and 70% ethanol for 2 days, and 0.25% GA for 7 days, (5) 0.5% GA for 5 days, a mixture of 2% GA, 65% ethanol, and 5% octanediol for 2 days and then 0.25% GA for 7 days. All treated bovine pericardia were tested for histological variables, lipid content, and mechanical properties including tensile strength and thermal stability. A total 10 kinds of differently treated bovine pericardia were implanted into rat subdermis and harvested 8 weeks later. Harvested pericardia were evaluated for calcium content. Result: No protein denaturation was observed microscopically after decellularization. There was a 32% mean decrease in tensile strength index after decellularization in the bovine pericardium group fixed. Octanediol preincubation attenuated the decrease in tensile strength and maintained thermal stability. TG and cholesterol were not affected by decellularization but were decreased by organic solvent. Calcium content was decreased after decellularization, and organic solvent preincubation decreased calcification in the non-decellularized bovine pericardium group. Conclusion: Decellularization and organic solvent preincubation have anti-calcification effects but decellularization may cause mechanical instability. A method of decellularization and fixation that does not cause damage to matrices will be needed for evaluation of the next step in using tissue-engineering for replacement of cardiac valves.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1183-1189
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• 2013

We investigated the effects of oyster shell extract (OSE) on papain-induced osteoarthritis in C57BL/6J mice. Osteoarthritis was induced in mice by a papain injection into the knee joint. The mice were divided into a total of five groups (n=8). The normal group was untreated, whereas the papain group (negative control) was induced with osteoarthritis and treated with water daily. The papain+DS group (positive control) was treated with diclofenac sodium. Papain+OSE groups were treated with OSE concentrations of 100 and 200 mg/kg/bw for 20 days. Proteoglycan content in articular cartilage was analyzed through safranine-O fast green staining and H&E staining. The histopathological changes in cartilage were measured by the Rudolphi score approach. The contents of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$, and IL-6 in plasma were analyzed by the ELISA method. After experiments, body weights of the treated groups were not significantly different compared with the normal group. Cartilage loss and joint instability significantly improved in a dose-dependent manner in the OSE-treated group compared with the papain group (P<0.05). Proteoglycan content was significantly higher in the OSE-treated group than the papain group (P<0.05). Osteoarthritis scores of the OSE-treated group were significantly decreased compared with the papain group (P<0.05). TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 content in the plasma of the papain+OSE treated groups significantly decreased in a dose-dependent manner compared with the papain group (P<0.05). These results suggest that OSE treatment might have anti-arthritic effects on papain-induced osteoarthritis in C57BL/6J mice.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.128-137
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• 1991

Peritoneal dialysis has been widely considered to be the dialytic treatment of choice for acute renal failure in infants and young children, because the technique is simple, safe and easily adapted for these patients. Also peritoneal dialysis in infants might have more effective ultrafiltration and clearance than in adults. In certain circumstances associated with hemodynamic instability, ordinary volume peritoneal dialysis(30-50 ml/kg body weight per exchange) or hemodialysis may not be suitable unfortunately. But frequent cycled, low volume, high concentration peritoneal dialysis may be more available to manage the hemodynamically untable acute renal failure of newborns and infants. Seven infants underwent peritoneal dialysis for hemodynamically unstable acute renal failure with low exchange volume($14.2{\pm}4.2ml/kg$), short exchange time(30 to 45 minutes) and hypertonic glucose solution(4.25% dextrose). Age was $1.9{\pm}1.3$ months and body weight was $4.6{\pm}1.6kg $. Etiology of acute renal failure was secondary to sepsis with or without shock(5 cases) and postcardiac operation(2 cases). Catheter was inserted percutaneously with pigtail catheter or Tenkhoff catheter by Seldinger method. Dialysate was commercially obtained Peritosol which contained sodium, chloride, potassium, magnesium, lactate and calcium. Net ultrafiltration(ml/min) showed no difference between low volume dialysis and control($0.27{\pm}0.09$ versus $0.29{\pm}0.09$) Blood BUN decreased from $95.7{\pm}37.5$ to $75.7{\pm}25.9mg/dl$ and blood pH increased from $7.122{\pm}0.048$ to $7.326{\pm}0.063$ after 24 hours of peritoneal dialysis. We experienced hyperglycemia which were controlled by insulin(2 episodes), leakage at the exit site(2), mild hyponatremia(1) and Escherichia coli peritonitis(1). Two children of low volume dialysis died despite the treatment. In our experience, low volume and high concentration peritoneal dialysis with frequent exchange may have sufficient ultrafiltration and clearance without significant complications in the certain risked acute renal failure of infants.

• Journal of Yeungnam Medical Science
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• v.21 no.1
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• pp.23-39
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• 2004

Background: It is important to provide health education to students to ensure a healthy life. Using the internet for health education may be a way to overcome the practical barriers to health education such as time and content. This study was conducted to investigate the demands for health education using the internet. Subjects and methods: Six hundreds and twenty-four and male female students in middle and high schools, who lived on Gyeongju-si and Seongju-gun in Gyeongsangbuk-do province, were interviewed by means of structured questionnaires, from March 5 to March 28, 2003. Results: More than 90% of the subjects had their own computers, and nearly 38% of those possessing their own computers had accessed internet sites related to health and medicine. Middle school students and in particular, female students were more desirous for health education through e-mail. Regarding content, the three major topics which the respondents wanted to learn about were healthy lifestyles, growth and development, and disease prevention. In terms of the interval for providing educational materials, over half of the students wanted information once a week. Most of the students wanted to have the quantity of the material be one page. In addition, there were numerous additional topics requested by the students such as sleep and health, contraception and family planning, safety education, cancer prevention, emotional instability of juveniles, the utilization of medical care facilities, stress management, etc. Conclusion: The students had a desire for health education through the use of e-mail, and methods and materials should be developed for appropriate health education using the internet.

• Journal of the Korean Arthroscopy Society
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• v.7 no.2
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• pp.169-175
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• 2003

Purpose : The purpose was to evaluate the early result of revision of failed anterior cruciate ligament (ACL) reconstruction. Materials and Methods : From August 1997 to February 2002, this report presents the findings of 18 patients who had revision surgery for failed ACL reconstruction. There was an average of 39 $(7\~120)$months from index procedure to the time of revision. Allografts were used in 14 $(78\%)$cases and autografts were used in 4 $(22\%)$cases and the revision procedures were assisted by arthroscopic technique. The majority of chief complaints were instability in 16 $(89\%)$cases. Sixteen $(89\%)$ cases had 1 previous reconstruction, 2 $(11\%)$ cases had 2. Before and after revision, patients were evaluated by Lachman test, pivot shift test, KT 2000, radiographs, Lysholm score and HSS score and subjective satisfaction. Results : Average length of followup was 27 $(12\~60)$months. Preoperatively, all cases were positive in Lachman test and pivot shift test. After revision the majority of cases were negative. Objectively improving stability was confirmed by KT 2000 and all average KT 2000 was 7.75 $(3.5\~12.5)$mm preoperatively and 2.36 $(1.0\~6.0)$mm at final followup. Lysholm score and HSS score were also improved from 72.6 $(66\~77)$ and 72.5 $(68\~78)$ preoperatively to 89.2 $(80\~92)$ and 88.2 $(81\~92)$ at final followup. Most $(89\%)$ of patients were satisfied with their results. The most common causes of failed ACL reconstruction were malposition of femoral tunnel in 11 $(61\%)$cases. Conclusion : Arthroscopic revision ACL surgery with adequate graft for failed ACL reconstruction was successful in objectively and subjectively improving stability. However, considering the most common causes of failure after ACL reconstruction were errors in surgical technique, it is important that the primary ACL reconstruction should be performed with correct surgical technique.

• Journal of the Korean Arthroscopy Society
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• v.15 no.1
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• pp.1-6
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• 2011

Purpose: The purpose of this prospective study is to compare the results of arthroscopic reconstruction of ACL using autologous hamstring tendon (Group 1) and autologous bone patella tendon bone (Group 2). Materials and Methods: From Jan. 2004 to Dec. 2007, fifty patients were analyzed in this study. A single surgeon performed the ACL reconstruction with autologous hamstring tendon (25 patients) and autologous bone patella tendon bone (25 patients) alternatively each other. The mean follow up period of two groups was 38 months (range 25~58 months). We evaluated the result of Lachman test, Pivot shift test as a physical examination and Lysholm score, Tagner activity scale as patients' satisfaction and functional status and Telometer for anterior instability of each groups at the time of final follow up. Results: In final results, negative or mild positive findings on Lachman test were 24 out of 25 cases (equally) in each groups.) Twenty two cases in the Group 1 and 21 cases in the Group 2 were negative on Pivot shift test. Lysholm scores mark 94.6 points in group 1 and 92.3 points in group 2 at the final follow up and Tegner activity scales mark 8.5 points (Group 1) and 8.1 points (Group 2) at the time of last follow up and there were no differences between the two groups statistically. The numbers of patients who have less than 5 mm of anterior translation of tibia under telometer at 20 degrees of knee flexion are 24 cases in group 1 and 23 cases in group 2. Conclusion: The overall improvements of clinical scores (Lysholm scores and Tegner Activity scales) of the group 1 were a little bit superior to those of the group 2, but there were no significant statistical difference between two groups.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.303-309
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• 2009

Purpose : To identify the short-term clinical outcomes of late preterm infants and to test the hypothesis that late preterm infants have more clinical problems during the early postnatal period than term infants. Methods : One hundred late preterm infants [gestational age (GA) $34^{+0}$-$36^{+6}$ weeks] and the same number of term infants (GA $37^{+0}$-$41^{+6}$ weeks) were randomly selected from 289 late preterm infants and 825 term infants born in the Seoul National University Bundang Hospital between January 2007 and December 2007, and their electronic medical records were reviewed and analyzed. Results : Compared to term infants, late preterm infants had significantly more medical problems such as temperature instability (odds ratio [OR] 8.7), hypoglycemia (OR 17.5), intravenous fluid infusion (OR 10.2), evaluation for sepsis (OR 9.4), respiratory problems (OR 7.5), apnea and bradycardia (OR 8.6), phototherapy for jaundice (OR 3.6), and feeding intolerance (OR 10.0). Hospital stay was also significantly longer in late preterm infants. Conclusion : Late preterm infants had significantly more medical problems and increased length of hospital stay compared to term infants. More attention should be given to caring for these late preterm infants in newborn nursery during the early postnatal period.

• Journal of the Korean Arthroscopy Society
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• v.16 no.2
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• pp.107-113
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• 2012

Purpose: The purpose of this study was to evaluate the posterior cruciate ligament (PCL) reconstruction with single bundle, single-incision technique using Achilles tendon and tibialis anterior allograft with ligament remnant preservation. Materials and Methods: Twenty six patients underwent PCL reconstruction was included. There were 21 males and 5 females. Mean age was 32 years. Used graft was a fresh frozen Achilles tendon allograft (group I, 14 cases) and tibialis anterior allograft (group II, 12 cases). Arthroscopic PCL reconstruction was performed using transtibial, single-incision and single bundle technique with remnant preserving as possible. For clinical evaluation, range of motion, posterior drawer test, Lysholm score, Tegner activity scale, International Knee Documentation Committee (IKDC) grade and posterior stress radiograph were used. The mean follow-up period was 21.6 months (12-40 months). Associated injuries were 5 medial collateral ligament injuries, which were treated by conservative method. Results: Range of motion (ROM) was returned to normal range in 24 cases, but ROM deficit under $10^{\circ}$ flexion was 2 cases at final follow-up period. Preoperative posterior drawer test was 17 cases in grade II and 9 cases in grade III. At final follow-up 13 cases returned within normal grade, 7 cases grade I and 6 cases grade II posterior instability. Lysholm mean score was improved from preoperatively 62 to 90 at final follow-up period. Tegner activity mean scale improved from preoperatively 3.5 to 5.6 at final follow-up period. IDKC grade was grade A was 3 cases, grade B 17 cases, grade C 6 cases. In posterior stress radiograph, posterior displacement was improved from mean 12 mm preoperative to 4.5 mm at final follow-up. There were no statistical differences between two groups in clinical evaluations. There were two cases of re-rupture of graft at the bone-tendon junction in group I. Conclusion: We had successful results of PCL reconstruction with single-incision, single bundle technique using Achilles and tibialis anterior allograft without difference between two groups in patients with PCL injury. There were more re-rupture of graft in Achilles tendon group.

• Membrane Journal
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• v.24 no.3
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• pp.194-200
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• 2014

The purpose of this study was to evaluate the performance of newly developed Large Pore Micro-Filtration (LPMF) membrane in Lab size for the application of water treatment, and to find its problems with solutions. The out-to-inside filtration hollow fiber LPMF membrane of which average pore size was $5{\mu}m$ was used at this study and its material was the PET braid reinforced PVDF. Filtration tests were done through gravity with 30 cm water head difference or pressure below 1.5 bar, and the backwash was done instantaneously with the filtrate after pressurizing it to about 4 bar. The water flux of the LPMF membrane with 0.2 bar TMP (Trans Membrane Pressure) was 2 times higher than $0.4{\mu}m$ MF membrane with $0.05{\mu}m$ UF filtrate of the tap water and it was measured also with 20~30 cm water head difference which showed over 800 LMH at 30 cm water head difference. And Time-To-Filter (TTF) was performed by using $5{\mu}m$ filter paper to optimize coagulants and dosage which enhanced filtrate's turbidity and stabilized filtration flux. When the LPMF was operated with 30 cm gravity with very high dose of inorganic coagulants, the flux was maintained over 80 LMH with 93.5~99.5% turbidity removal. Especially, the filtration was maintained stably in the flux and about 97% of the recovery rate by instantaneous pressurized backwash with about 4 bar of the filtrate when the packing density was about 19%. But there was instability in filtration, since the TMP was continuously going up by inefficient backwash when the packing density was 43%.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.996-1002
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• 2003

Purpose : In Rett syndrome patients, the incidence of sudden death is greater than that of the general population, and cardiac electrical instability including fatal cardiac arrhythmia is a main suspected cause. In this study, we are going to find out the possible cause of the higher risk of sudden death in Rett patients by the evaluation of heart rate variability, a marker of cardiac autonomic activity and corrected QT intervals. Methods : Diagnosis of Rett syndrome was made by molecular genetic study of Rett syndrome (MECP2 gene) or clinical diagnostic criteria of Rett syndrome. Heart rate variability and corrected QT intervals were measured by 24 h-Holter study in 12 Rett patients, and in 30 age-matched healthy children with chief complaints of chest pain or suspected heart murmurs. The were compared with the normal age-matched control. Results : Patients with total Rett syndrome, classic Rett syndrome, and Rett variants had significantly lower heart rate variability(especially rMSSD)(P<0.05) and longer corrected QT intervals than age-matched healthy children(P<0.05). Sympathovagal balance expressed by the ratio of high to low frequency(LF/HF ratio) also showed statistically significant differences between the three groups considered(P<0.05). Conclusion : A significant reduction of heart rate variability, a marker of autonomic disarray, suggests a possible explanation of cardiac dysfunction in sudden death associated with Rett syndrome.