화농성 간농양으로 오인한 혼합형 간세포-담관암종 1예

백승석 ( Seung Suk Baek ),윤아일린 ( Eileen L. Yoon ),김현정 ( Hyun-jung Kim ),배경은 ( Kyung Eun Bae ),박경미 ( Kyeongmee Park ),최원충 ( Won-choong Choi ) 대한간암학회 2017 대한간암학회지 Vol.17 No.2

Heterogeneous features of liver cancer can mimic liver abscess. Therefore it is essential to double- check tumor markers in the diagnosis of liver abscess. Herein, we report a case of combined hepatocellular-cholangiocarcinoma (cHC) occurred in an unrecognized chronic hepatitis B patient initially misdiagnosed as liver abscess. A 49-year old male initially presented with chill, right upper quadrant pain, and a liver mass. Mass showed peripheral enhancement in arterial phase of computed tomography, which was not typical for hepatocellular carcinoma (HCC). Strikingly elevated alpha-fetoprotein and fine needle aspirated pathology revealed HCC. Despite discordant image findings he was treated with transarterial chemoembolization. He was treated with sorafenib due to metastatic retrocaval lymphadenopathy afterwards. The mass presumed to be HCC progressed with sorafenib. It was surgically resected and he was finally confirmed as cHC. Discordant tumor markers with presumptive image findings should prompt the suspicion of rare type of primary liver cancer, the cHC. (J Liver Cancer 2017;17:174-181)

광학용 아크릴 점착제 제조 및 점착특성에 관한 연구

백승석(Seung Suk Baek),장세정(Se Jung Jang),이종훈(Jong Hoon Lee),고동한(Dong Han Kho),이상훈(Sang Hoon Lee),황석호(Seok Ho Hwang) 한국고분자학회 2014 폴리머 Vol.38 No.2

본 연구는 2-ethylhexyl acrylate와 2-hydroxyethyl acrylate 기본구조에 isobornyl acrylate와 tetrahydrofurfurylacrylate(THFA)의 조성비를 변화시키면서 광중합된 4원 공중합체를 합성한 후 가교제로 1,6-hexanediol diacrylate가혼합된 시럽을 제조하였다. 합성한 시럽에 UV-광원을 조사시켜 점착제를 제조한 후 점착특성과 광학특성을 고찰하였으며 시럽의 기본물성인 고형분, 점도, 및 분자량 분석도 수행하였다. THFA의 함량이 증가할수록 시럽의 분자량은 감소하였으나 고형분은 반대로 증가하였다. 점착제의 박리강도는 THFA의 함량에 따른 반비례관계를 나타내고점착제의 표면에너지는 비례관계를 나타내었다. 또한 모든 점착제에서 92% 이상의 광투과도와 1.0%이하의 haze값,그리고 1.0 이하의 색차계값을 보여주었다. To prepare acrylic pressure sensitive adhesives (PSAs), quaternary copolymer syrups were photopolymerized from 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate as default constituents and isobornyl acrylate and tetrahy-drofurfuryl acrylate (THFA) as variable constituents. After polymerization, 1,6-hexanediol diacrylate and photoinitiator were added and then crosslinked by UV-irradiation to prepare the PSAs. The characteristics of the syrup such as viscosity, molecular weight, and solid content were investigated. As increasing THFA contents, the relationship between molecular weight and solid content of the syrup was reciprocal. Also, the relationship between peel strength and surface energy of the PSAs showed the same tendency. All the PSA samples showed high transmittance (more than 92%), low haze (less than 1.0%) and low color-difference (less than 1.0).

투명 아크릴 기판에 실버그리드(Silver Grid)를 함몰시킨 유연 투명전극 제조

백승석(Seung-Suk Baek),윤대건(Dai Geon Yoon),황경석(Gyungseok Hwang),장수희(Su-Hee Jang),진병두(Byung-Doo Chin),황석호(Seok-Ho Hwang) 한국고분자학회 2017 폴리머 Vol.41 No.3

본 연구에서 광경화성 아크릴 단량체 조성물(methyl methacrylate, 2-hydroxyethyl acrylate, poly(ethylene glycol) diacrylate)을 이용한 고분자 기판 내부에 실버그리드(silver grid)를 잉크젯공정(ink-jet)과 전사공정(transfer process)으로 함몰시킨 유연 투명전극 기판을 제조하였다. 인터페로미터를 사용하여 광경화된 고분자 기판 내부에 실버그리드의 함몰된 형태 및 표면을 확인하였으며, 그것의 광학적 특성과 밴딩테스트 후 전기적 특성으로 제조된 유연 투명전극 기판의 물성을 고찰하였다. 유연 투명전극 기판으로서의 유용성을 확인하기 위해 poly(3-hexylthiophene): [6,6]-phenyl-C61 butyric acid methyl ester(P3HT:PCBM)으로 유기 태양전지 소자를 제작하여 2.52%의 효율 특성을 얻었다. Using the UV-curable acrylate formulations consisting of methyl methacrylate, 2-hydroxyethyl acrylate and poly(ethylene glycol) diacrylate), flexible and transparent electrode embedded silver grid into the polymer substrate was fabricated through ink-jetting technique and transfer process. The profile morphologies and surface characteristics of silver grid in the polymer substrate were estimated by interferometer. Furthermore, the optical properties as well as electrical- resistance changes during bending test of the electrode were also measured. As one of utilitarian applications for the electrode, the optimized organic solar cell was constructed on the electrode by using poly(3-hexylthiophene):[6,6]- phenyl-C61 butyric acid methyl ester (P3HT:PCBM) system and then power conversion efficiency of the device was 2.53%.

광학용 아크릴 점착제내 단량체 화학구조에 따른 점착특성

백승석(Seung Suk Baek),장세정(Se Jung Jang),이상원(Sang Won Lee),황석호(Seok Ho Hwang) 한국고분자학회 2014 폴리머 Vol.38 No.5

2-Ethylhexyl acrylate와 2-hydroxyethyl acrylate의 기본구조에 다양한 곁사슬 화학구조를 가지는 단량체의 종류를 변화시키면서 광중합된 고투명 3원 공중합체 시럽을 합성하였다. 시럽에 가교제로 1,6-hexanediol diacrylate와 광개시제를 혼합한 후 UV-광원을 조사시켜 점착제(PSAs)를 제조하여 점착특성과 광학특성을 고찰하였다. PSAs의 점착물성은 단량체 종류에 따른 조성비에 크게 의존하고 있으나, 광학적 특성이 유사함을 확인하였다. 상대적으로 부피가 큰 분자이면서 헤테로 원소를 포함하고 있는 IBOA, THFA, ACMO 단량체가n-BA, VAc, CHA 단량체보다 좋은 점착물성을 보여주었다. To prepare transparent acrylic pressure sensitive adhesives(PSAs), terpolymer syrups were photo polymerized from 2-ethylhexyl acryl ate and 2-hydroxyethyl acrylate with third monomerhaving different chemical structure. After polymerization, 1,6-hexanediol diacrylate as a crosslinker and a photoinitiatorwere added and then UV-irradiated to prepare the PSAs. The adhesion performances and optical characteristics of the PSAs were investigated. Their adhesion performance was dependent on the composition of monomers in the polymer chain but optical properties were maintained at a suitable level. The PSAs prepared by bulky and heteroatom-containing monomers such asI BOA, THFA, and ACMO showed better adhesion performance than others.

가교제 변화에 따른 광학용 아크릴 점착제의 점착물성에 대한 연구

백승석 ( Seung Suk Baek ),장세정 ( Se Jung Jang ),황석호 ( Seok Ho Hwang ) 한국고무학회 2014 엘라스토머 및 콤포지트 Vol.49 No.3

아크릴 단량체인 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA), isobornyl acrylate (IBOA)를 광중합을 통하여 3원 공중합체 시럽을 합성하였다. 이관능기 아크릴 단량체인 1,6-hexanediol diacrylate (HDDA), poly(ethylene glycol) diacrylate (PEGDA, Mn = 250, 575, 700)를 가교제로 사용하여 semi-IPN형 감압성 점착제 (Pressure sensitive adhesives; PSAs)를 UV-광가교 시켜 제조하였다. 가교제 변화에 따른 감압성 점착제의 점착특성, 저장탄성율, 그리고 광학특성을 고찰하였으며, 점착특성과 저장탄성율은 가교제의 화학구조와 분자량에 의존하였다. 광학특성은 모든 감압성 점착제에서 92.5 % 이상의 광투과도 (at 550 nm), 1.0% 이하의 haze값, 0.3 이하의 색차계값을 보임을 확인하였다. 결과적으로 가교제의 종류에 영향을 받지 않음을 확인하였다. Terpolymer syrups were photopolymerized from 2-ethylhexyl acrylate, 2-hydroxylethyl acrylate and isobornyl acrylate to prepare acrylic pressure sensitive adhesives (PSAs). After polymerization, various crosslinkers as 1,6-hexanediol diacrylate (HDDA), poly (ethylene glycol) diacrylate (PEGDA, Mn = 250, 575, and 700) were added and then UV-irradiated to prepare the semi-IPN type PSAs. Their adhesion performance and storage modulus (G`) were strongly dependent on their chemical structure and molecular weight of the crosslinkers. Optical properties such as transmittance (> 92.5 %), haze (< 1.0 %) and color-difference (< 0.3) of PSAs samples were not affected by crosslinker types used in this study.

4,4`-Thiodibenzenethiol을 이용한 광경화형 에폭시 아크릴레이트 합성과 굴절률에 관한 연구

황석호(Seok Ho Hwang),백승석(Seung Suk Baek),이상원(Sang Won Lee) 한국고분자학회 2013 폴리머 Vol.37 No.1

4,4`-Thiodibenzenethiol을 기반으로 이관능 에폭시 수지인 4,4`-thiodibenzenethiol diglycidyl ether를 직접합성 법으로 합성하였다. 합성된 에폭시 수지가 광경화가 가능하도록 acrylic acid와 반응시켜 광경화형 고굴절 이관능 에 폭시 아크릴레이트인 4,4`-thiodibenzenethiol diglycidyl ether diacrylate를 합성하였으며 1H NMR과 FTIR을 이용하 여 화학구조를 확인하였다. 이관능 에폭시 아크릴레이트와 함께 반응성 희석제인 2-phenoxythiol ethyl acrylate를 5, 10, 15, 20, 30 wt% 희석하여 점도와 굴절률과의 상관관계를 확인하였으며 광경화 후 경화필름의 굴절률 변화를 고 찰 하였다. 반응성 희석제의 농도가 증가함에 따라 경화물의 경화도가 낮아졌으며, 경화도가 클수록 경화 후 굴절률 은 높아지는 경향을 확인하였다. UV-curable high refractive index di-functional epoxy acrylate, 4,4`-thiodibenzenethiol diglycidyl ether diacrylate, was synthesized from acrylic acid and 4,4`-thiodibenzenethiol diglycidyl ether that was obtained by reacting 4,4`- thiodibenzenethiol and epichlorohydrin using a direct method (Taffy process). Its chemical structure was identified by 1H NMR and FTIR. After its dilution with a reactive diluent, 2-phenoxythiol ethyl acrylate as 5, 10, 15, 20, and 30 wt% content, the relationship between their viscosity and refractive index was investigated. Their degree of cure decreased with increasing the amount of reactive diluent, and the refractive index of UV-cured film increased with increasing the degree of cure.

증 례 : 복수를 동반한 급성 간부전으로 발현된 공격성 자연살해세포 림프종 1예

이종호 ( Jong Ho Lee ),오태훈 ( Tae Hoon Oh ),박지영 ( Ji Young Park ),전태주 ( Tae Joo Jeon ),백승석 ( Seung Suk Baek ),하태환 ( Tae Hwan Ha ),박성은 ( Sung Eun Park ) 대한내과학회 2016 대한내과학회지 Vol.90 No.1

급성 간부전의 원인은 바이러스성 간염과 약물이 흔하며 공격성 NK 세포 림프종은 매우 드문 원인으로 알려져 있다. 저자들은 복수를 동반한 급성 간부전 환자에서 복수 검사와 혈액 검사, 영상학적 검사에서 원인이 명확하지 않고 경험적치료에 반응하지 않아 간 생검을 통해서 공격성 NK 세포 림프종을 급성 간부전의 원인으로 진단할 수 있었던 증례를 문헌고찰과 함께 보고한다. Acute liver failure (ALF) is a medical emergency triggering an urgent need for liver transplantation. The most common causes of ALF are drug- and virus-associated hepatitis, but hematological malignancies such as an aggressive natural killer cell lymphoma (ANKL) can uncommonly cause ALF. A 50 year-old male presented with ascites, jaundice, and encephalopathy. The ascitic fluid had a serum-ascites albumin gradient of 0.3 g/L, and contained atypical lymphocytes, which were positive for CD3. Computed tomography revealed mild hepatomegaly and multiple nodules in both lobes of the liver. A liver biopsy showed that the liver parenchyma had been infiltrated by malignant lymphoid cells, and exhibited marked sinusoidal dilatation. Immunohistochemically, the lymphoid cells were positive for CD3, CD56, and Epstein-Barr virus-encoded small RNA. The patient was diagnosed with ANKL causing ALF, and died on hospital day 12. This case shows that infiltration of the liver with ANKL can (rarely) cause ALF. (Korean J Med 2016;90:32-36)

결핵균 중합효소연쇄반응 양성으로 진단된 담낭 결핵

류미진 ( Mi Jin Ryu ),전태주 ( Tae Joo Jeon ),박지영 ( Ji Young Park ),최예나 ( Ye Na Choi ),백승석 ( Seung Suk Baek ),신동현 ( Dong Hyun Sinn ),오태훈 ( Tae Hoon Oh ),김정연 ( Jung Yeon Kim ) 대한소화기학회 2014 대한소화기학회지 Vol.63 No.1

Gallbladder tuberculosis is an extremely rare disease that is rarely reported in the literature. Arriving at the correct diagnosis of gallbladder tuberculosis is difficult, and it is usually made by histopathologic examination after cholecystectomy. However, due to the low sensitivity of acid-fast stain and culture result, diagnosing gallbladder tuberculosis is still demanding even after tissue acquisition. To overcome this problem, tuberculosis-polymerase chain reaction (TB-PCR) is performed on the resected specimen, which has high sensitivity and specificity. A 70-year-old female who had previously undergone total gastrectomy for advanced gastric cancer was admitted with right upper quadrant pain. Abdominal ultrasonography and computed tomography revealed acute cholecystitis without gallstones or sludge. She underwent cholecystectomy and the histopathologic finding of the specimen showed chronic active cholecystitis without gallstones or sludge. Because she was suspected to have pulmonary tuberculosis, TB-PCR was also performed on the resected gallbladder. TB-PCR showed positive reaction for Mycobacterium tuberculosis and we could diagnose it as gallbladder tuberculosis. Herein, we present a case of gallbladder tuberculosis diagnosed by TB-PCR from resected gallbladder. (Korean J Gastroenterol 2014;63:51-55)