• Korean Chemical Engineering Research
• /
• v.49 no.1
• /
• pp.75-82
• /
• 2011

Five different composition UV-cured poly(urethane acrylate-co-acrylic acid) (PU-co-AA) films have been prepared by reacting isophorone diisocyanate(IPDI), polycaprolactone triol(PCLT), 2-hydroxyethyl acrylate(HEA), and different weight ratio trimethylolpropane triacrylate(TMPTA) and acrylic acid(AA) as diluents, and characterized using a Fourier transform infrared spectroscopy(FT-IR). The adhesion properties onto the stainless steel, morphology, mechanical hardness, and electrical property of UV-cured PU-co-AA films were investigated as a function of acrylic acid(AA) content. All the PU-co-AA films are structure-less and the molecular ordering and packing density decreased with increasing content of AA due to the flexible structure and -COOH side chains in AA. The crosscut test showed that PU-co-AA films without AA and with low content of AA showed 0% adhesion(0B) and the adhesion of PU-co-AA films in the range of 40-50% AA increased dramatically as the content of AA increases. The pull-off measurements showed that the adhesion force of PU-co-AA films to stainless steel substrate varied from 6 to 31 kgf /$cm^2$ and increased linearly with increasing AA content. The mechanical hardness also decreased as the content of AA increases. This may come from relatively linear and flexible structure in AA and low crystallinity in PU-co-AA films with higher content of AA. The higher AA-containing PU-co-AA films showed higher dielectric constant due to the increase of polarization by introducing AA monomer. In conclusion, the physical properties of UV-cured PU-co-AA films are strongly dependent upon the content of AA and the incorporation of AA in polyurethane acrylate is very useful way to increase the adhesion strength of UV-curable polymers on the stainless steel substrate.

• Journal of Periodontal and Implant Science
• /
• v.35 no.1
• /
• pp.199-216
• /
• 2005

치주치료의 가장 중요한 목적은 상실된 치주조직의 형태적, 기능적 재건이다. 법랑기칠 단백질 유도체(enamel matrix derivative: EMD)는 치주 병소에 사용시 상피세포의 증식을 억제하며 치주인대 및 백악아세포를 활성화시켜 무세포성 백악질 및 치주인대와 골조직의 생성을 유도한다고 보고되고 있다. 또한 법랑기질 단백칠 유도체는 골모세포의 증식 및 분화를 촉진시키며 alkaline phosphatase의 활성 및 mineralized nodule의 형성을 촉진시킨다고 보고되고 있다. 이에 본 연구에서는 토끼 두개골 결손부에 법랑기질 단백질 유도체와 이종골 이식재를 이식한 후 골밀도를 방사선학적으로 분석하고, 신생골 형성 및 주변 조직 반응을 조직학적으로 관찰, 평가하고자 하였다. 토끼 두개골에 6mm trephine bur(외경 8mm)를 이용하여 경뇌막에 손상을 주지 않도록 하면서 4개의 결손부를 형성하였다. 아무것도 이식하지 않은 군을 음성 대조군으로, 이종골 이식재 ($Bio-Oss^{(R)}$, Geistlich, Wolhusen, Switzerland)을 이식한 군을 양성 대조군으로 설정하였다. 법랑기질 단백질 유도체 ($Emdogain^{(R)}$, Biora, Inc., Sweden)만 이식한 군과 법랑기질 단백질 유도체와 이종골 이식재를 혼합하여 이식한 군을 설험군으로 설정하였다. 각각의 재료를 이식한 후 비흡수성 차폐막 ($Tefgen^{(R)}$, Lifecore Biomedical, Inc., U.S.A.)을 위치시키고 흡수성 봉합사로 일차봉합을 시행하였다. 각 군당 술 후 1, 2, 4주의 치유기간을 설정하였다. 동물을 희생시킨 후 두개골을 절제하여 먼저 방사선학적인 골밀도측정을 시행한 후 10% formalin에 고정한 후 통법에 따라 조직표본을 제작하여 광학현미경으로 관찰하였다. 1. 방사선학적인 평가에서 1, 2, 4주에 대조군과 법랑기질 단백질 유도체만 이식한 군과 비교해 이종골 이식재만 이식한 군과 이종골 이식재에 법랑기질 단백질 유도체를 이식한 군에서 더 큰 골의 밀도를 보이고 있었다 (P<0.01). 하지만, 동일한 시기에 대조군과 법랑기질 단백질 유도체만 이식한 군과의 차이는 발견할 수 없었으며 (P>0.05), 이종골 이식재만 이식한 군과 이종골 이식재에 법랑기질 단백질 유도체를 이식한 군의 차이 또한 발견할 수 없었다 (P>0.05). 2. 조직학적인 평가에서 1, 2, 4주에 대조군과 법랑기질 단백질 유도체만 이식한 군과 비교해 이종골 이식재만 이식한 군과 이종골 이식재에 법랑기질 단백질 유도체를 이식한군에서 골의 형성이 더 진행됨을 알 수 있었다. 법랑기질 단백질 유도체만 이식한 군이 대조군보다 2주에서 더 많은 신생골을 볼 수 있었으며, 이종골 이식재에 법랑기질 단백질 유도체를 이식한 군이 이종골 이식재만 이식한 군보다 1, 2주에서 더 많은 신생골을 관찰할 수 있었다. 이상의 결과에서 법랑기질 단백질 유도체는 토끼 두개골 결손부 치유단계에서 초기 골 형성을 촉진하는 것으로 사료되며 골 이식시에 법랑기질 단백질 유도체를 적용하는 것은 유용한 술식으로 사료된다.

• The Korean Journal of Nuclear Medicine
• /
• v.33 no.1
• /
• pp.76-83
• /
• 1999

Purpose: We performed this study to compare T1-201 and Tc-99m MIBI scans for the differentiation of malignant from benign breast mass. Materials and Methods: Thirty-eight female patients underwent T1-201 breast scan and thirty-two of them also underwent Tc-99m MIBI scan of the breast. After intravenous injection of 74-111 MBq of T1-201, early (10 minutes) and delayed (3 hours) images were obtained. Then, 555-740 MBq of Tc-99m MIBI was injected and images after 30 minutes were obtained. We compared T1-201 and Tc-99m MIBI scans with pathologic results. Results: Twenty-three patients were confirmed to have infiltrating duct carcinoma and fifteen patients to have benign breast mass by excisonal biopsy. The sensitivity of early and delayed T1-201 scan and Tc-99m MIBI scan in the detection of malignant breast lesion were 100% (23/23), 82% (18/22), and 90% (18120), respectively. The sensitivity of early T1-201 scan was significantly higher than that of delayed T1-201 scan (p<0.05). The specificity of early and delayed T1-201 scan and Tc-99m MIBI scan were 73% (l1/15), 73% (l1/15) and 83% (10/12), respectively (p: not significant). Three patients out of nine with fibroadenoma and one patient with atypical duct hyperplasia were false positive in both early and delayed T1-201 scans. The size of fibroadenoma with false positive in early and delayed T1-201 scan (4 cases) was larger than that of 11 fibroadenoma with true negative scan (p<0.01). Metastatic axillary lymph node involvement was present in fifteen patients. The sensitivity to detect metastatic nodes was 38% (5/13) for early T1-201 images, 15% (2/13) for delayed T1-201 images, 58% (7/12) for Tc-99m MIBI planar images and 67% (4/6) for Tc-99m MIBI SPECT. The sensitivity of Tc-99m MIBI planar or SPECT was significantly higher than that of delayed T1-201 images (p<0.05). Conclusion: Early T1-201 and Tc-99m MIBI scan are useful noninvasive methods to differentiate malignant from benign mass of breast Tc-99m MIBI scan was sensitive in detecting axillary lymph node metastasis in patients with breast cancer.

• Nuclear Medicine and Molecular Imaging
• /
• v.43 no.6
• /
• pp.543-556
• /
• 2009

Purpose: We studied the patterns of FDG uptake of primary papillary thyroid microcarcinoma (PTMCa) lesions and benign thyroid nodules in dual time point $^{18}F$-FDG PET/CT imaging. Materials and Methods: Consecutive 134 patients (154 lesions) with PTMCa and 49 patients (61 nodules) with benign thyroid nodules equal to or less than 1.0 cm who underwent dual time point $^{18}F$-FDG PET/CT study before surgery were enrolled. We calculated the maximum standardized uptake value of PTMCa and benign nodules in both time points, and percent change of SUVmax (${\Delta}%SUVmax$) and lesion to background ratio of SUVmax (${\Delta}L:B$% ratio) between both time points. The mean time interval between scans was $23.4{\pm}4.4$ minutes (thyroid to thyroid interval: $10.7{\pm}4.4$ minutes). Results: The mean of SUVmax of PTMCa was increased from $4.9{\pm}4.3$ to $5.3{\pm}4.7$ (p<0.001) and ${\Delta}%SUVmax$ was $12.3{\pm}23.6%$. But, the mean of SUVmax of benign nodules was no definite change ($2.1{\pm}1.0$ to $2.1{\pm}1.3$, p=0.686) and ${\Delta}%SUVmax$ was $-0.3{\pm}20.5%$. Of the 154 PTMCa, 100 nodules (64.9%) showed an increase in SUVmax over time, while 19 (31.1%) of the 61 benign thyroid nodules showed an increase (p<0.001). The dual time point $^{18}F$-FDG PET/CT found more PTMCa in visual assessment (62.3% vs. 76.6%, p=0.006), even in smaller than 0.5 cm (38.6% vs. 60.0%, p=0.011). Conclusion: Dual time time $^{18}F$-FDG PET/CT imaging was more useful than single time point $^{18}F$-FDG PET/CT imaging for distinction between PTMCa and benign nodule, especially when nodule showed equivocal or negative findings in single time point $^{18}F$-FDG PET/CT imaging or was smaller than 0.5 cm.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.15 no.1
• /
• pp.113-116
• /
• 2011

Purpose: Acetylcholine receptor antibodies cause acetylcholine receptor loss, which is responsible for failure of the neuromuscular junction in the acetylcholine receptor autoantibody. The disease characterized by muscle weakness and fatigue, myasthenia gravis(MG) occurs when the body inappropriately produces antibodies against acetylcholine receptors, and thus inhibits proper acetylcholine signal transmission. And this reason, the measurement of acetylcholine receptor antibodies can be of considerable value in disease diagnosis. Methods: From 2010. August to September, we tested orderd AchRAb 19 samples to get the results. 1. Pipette $5{\mu}{\ell}$ undiluted patient sera and kit control and add 125I AChR $50{\mu}{\ell}$ and incubate at R.T for 2 hours. 2. Pipette $50{\mu}{\ell}$ of anti-human IgG into each tube, and incubate at $2{\sim}8^{\circ}C$ for 2 hours. 3. Pipette $25{\mu}{\ell}$ precipitation enhancer into each tube and add 1mL washing solution into all tubes. 4. Centrifuge each tube for 20minutes at $2{\sim}8^{\circ}C$ at 1500g. 5. Aspirate or decant the supernatant. 6. Pipette 1 mL washing solution into all tubes and resuspend the pellet and repeat centrifugation. 7. Aspirate or decant the supernatant and count all tubes on a gamma counter. Results: Cut off value is 0.2 nmol/L and the results taken below 0.2 nmol/L are negative, the results above that identified as being positive values. We assayed the 19 patients samples and got 7 positive results. Of which, 6 patients were diagnosed as MG.(85.7%). Conclusions: Acetylcholine Receptor autoantibody test is intended for use by persons only for the quantitative determination of it in human serum. Even if measurement of the antibodies is not a routine test, it can be of considerable value in disease diagnosis.

• Journal of Food Hygiene and Safety
• /
• v.28 no.2
• /
• pp.146-151
• /
• 2013

Perilla frutescens usually dieted in East Asian country such as Korea and Japan. Antioxidant, antiinflammatory and anticancer activities of perilla leaves have been founded. In previous study, we confirmed that caffeic acid, major compound of perilla, was accumulation by sucrose aqueous solution and thus antioxidant effect of perilla was enhanced. In this study, we investigated the protective effect of functional perilla leaves extract (PLE) against tert-butyl hydroperoxide(t-BHP) induced-oxidative hepatotoxicity. The pretreatment with PLE (250, 500 and 1000 mg/kg b.w.) for 5 days before a single dose of t-BHP (i.p.; 0.5 mmol/kg) significantly lowered the serum levels of aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase dose-dependently. And we confirmed that the indicators of oxidative stress were remarkably reduced in the liver, such as the glutathione contents and malondialdehyde, marker of lipid peroxidation. Pathological histology of the rat livers tissues showed that PLE reduced the hepatocyte degeneration and neutrophilic infiltration of liver induced by t-BHP. These results suggest that functional perilla frutescens has the protective effect of liver against t-BHP-induced oxidative hepatic stress in rats.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.4 no.1
• /
• pp.10-17
• /
• 2001

Purpose: We measured anti-H. pylori IgG in Korean elementary school children living in Shinchon area of Seoul, Korea to evaluate the influence of environmental living standards on H. pylori infection. Methods: IgG antibodies to H. pylori were measured in plasma using a commercial ELISA kit (GAP IgG Helicobacter pylori, Bio-Rad Laboratories Inc., Hercules, CA, USA). Information on environmental status such as place of birth, parental income, type of housing, number of persons in the household, parents' occupation, family history of peptic ulcer disease and gastric cancer was obtained. Statistical analysis was done by Chi-square and logistic regression test using SPSS $7.0^{TM}$ for Windows. Results: Study subjects consisted of 571 children, and the age distribution ranged from 6.0 to 13.6 years with a mean of $9.6{\pm}1.8$ years. Male-to-female ratio was 1.1:1. The seropositive rates of H. pylori infection ranged from 10.4% in children aged 6 years to 30.9% in 12 year-old group, overall 16.8%. The prevalence of H. pylori infection progressively increased with age, but there was no significant difference in seropositive rates among children in different age groups (p=0.06). Seropositive rates of anti-H. pylori IgG on the basis of gender, place of birth, parental income, type of housing, parents' occupation, family history of peptic ulcer disease and gastric cancer showed no statistically significant difference. Interestingly, however, seropositive rate of anti-H. pylori IgG showed statistical significance in relation to number of persons in the household (p=0.003; Odds ratio 1.50 by logistic regression test). Conclusion: These results suggest that number of persons in the household is the most important factor among environmental living standards, and that risk of H. pylori infection increases by increment of 1.5 times as the number of persons in the household increases by one.

• Pediatric Infection and Vaccine
• /
• v.9 no.2
• /
• pp.215-221
• /
• 2002

Purpose : This study was done to compare the vitamin A levels between hospitalized patients of measles symptoms and of the other infectious diseases common in childhood (bronchiolitis, penumonia, gastroenteritis and etc.). Methods : We have set up a population of 133 hospitalized patients of measles symptoms in the pediatric department of Kangnam Sacred Heart Hospital between Nov. 2000~Apr. 2001 and compared them to a group of 30 hospitalized patients of other infectious diseases between Dec. 2001~Feb. 2002. The whole patients were divided into three groups by diagnosing measles-specific IgM antibody positive as measles group(n=104), negative as measles-susepcted group(n=29) and other infectious disease group. And we compared the vitamin A levels, clinical symptoms, and general hematological and biochemical results. Results : Among the 104 measles patients, the concentrated age groups were 10 12 months(n=24, 23.1%), 13~15 months(n=16, 15.3%) and 16 months~4 years of age(n=24, 23.1%). The mean levels of vitamin A of measles and measles-susepcted groups were $69.6{\pm}28.6{\mu}g/dL$ and $75.2{\pm}34.4{\mu}g/dL$, respectively, and that of other infectious disease group was $28.1{\pm}17.5{\mu}g/dL$. Conclusion : The mean levels of vitamin A of both measles and measles-suspected groups were significantly higher than that of other infectious disease group(P<0.05) and showed no significant correlations with clinical symptoms and hospitalization duration.

• Pediatric Infection and Vaccine
• /
• v.25 no.2
• /
• pp.72-81
• /
• 2018

Purpose: This prospective study aimed to investigate the therapeutic efficacy of lamivudine in children with chronic hepatitis B virus (HBV) infection. Methods: During July 2003 through October 2015, children with chronic hepatitis B who visited our institution were included in this study. Fifty-five patients, who received first-line treatment of lamivudine (3 mg/kg, 100 mg maximum) for over three months, were enrolled. After initiating lamivudine, alanine aminotransferase (ALT), HBV-DNA, and HBV markers were followed up at 1 month, 3 months, and every 3 months, thereafter. The treatment endpoint was determined as 1) normalization of ALT, 2) HBeAg seroconversion, and 3) anti-HBe positivity for twelve consecutive months. Results: Thirty-one male (56.4%) and 24 female (43.6%) patients were included. The mean age at treatment initiation was 8.1 years. The mean duration of treatment was 23.4 months. ALT normalization was found in 98.2% (54 of 55). Anti-HBe seroconversion was found in 70.6% (36/51). Loss of HBsAg was found in 10.9% (6/55). All biochemical responses occurred under age seven. The rate of virologic response (defined as HBV-DNA <2,000 IU/mL) at six months after treatment initiation was 78.7% (37/47). At twelve months after reaching treatment endpoint, 87.2% (34/39) maintained their virologic response. Resistance to lamivudine was found in 16.4% (9/55). Conclusions: Lamivudine treatment in Korean pediatric patients with chronic hepatitis B showed better outcomes compared with other studies that implemented similar protocols in foreign populations. Further studies are needed to investigate the efficacy of newly recommended antiviral drugs on the Korean pediatric population.

• Radiation Oncology Journal
• /
• v.21 no.2
• /
• pp.149-157
• /
• 2003

Purpose: The purpose of this study was to determine if there were prognostic differences between BRCA related and BRCA non-related Korean patients with early-onset breast carcinomas. Materials and Methods: Sixty women who had developed breast cancers before the age of 40, and who were treated at the Soonchunhyang University Hospital, were studied independently of their family histories. The age range was 18 to 40 with a median of 34.5 years. Lymphocyte specimens from peripheral blood were studied for the heterozygous mutations of BRCA1 and BRCA2 using direct sequencing methods. Immunohistochemistry was peformed on the paraffin-embedded tissue blocks that were available. Results: Eleven deleterious mutations (18.3%, 6 in BRCA1 and 5 in BRCA2) and 7 missense mutations of unknown significance (11.7%), were found among the 60 patients. More than half of the mutation were novel, and were not reported in the database. Most of the BRCA-associated patients had no history of breast cancer. No treatment related failures were observed in the BRCA carriers, with the exception of one patient that had experienced a new primary tumor of the contralateral breast. The seven year relapse free survival rate were 50 and 79% In the BRCA carrier and BRCA negative patients, respectively. Although the expression of estrogen and progesterone receptors were less common, and histological features more aggressive, in the BRCA associated tumors, the outcome of the patients with BRCA mutations was not poorer than that on the patients without deleterious mutations. Conclusion.: Despite the BRCA mutation carriers having adverse prognostic features, the recurrence rate was relatively lower than that in the BRCA non-carrying Korean patients wi4h early-onset breast carcinomas. In addition, although the prevalence of the BRCA mutation in Korean patients was higher than that in white patients, the penetrance of the cancer seemed to be relatively low in Korean women carrying BRCA mutations. A large population based study of the BRCA mutation, with a long-term follow-up of the study patients will be required to confirm these results.