Biomass 유래 퓨란계 단량체를 이용한 폴리에스터의 중합 및 특성 연구

정용석(Yong Seong Chung),이영철(Young Chul Lee),서강진(Kang Jin Seo),김명준(Myeong Jun Kim),정지혜(Ji Hea Jeong),노시태(Si Tae Noh) 한국고분자학회 2011 폴리머 Vol.35 No.6

바이오매스에서 유래된 2,5-dihydroxymethylfuran(DHMF)을 KMnO4 산화반응으로 furan-2,5- dicarboxylic acid(FDCA)를 합성하였다. 합성한 FDCA와 다이올류를 에스테르화 반응과 축중합 반응을 진행시 켜 폴리에스터를 중합하였다. 폴리에스터는 NMR을 통해 조성을 분석하였고 DSC와 TGA를 통해 열적특성을 분 석하였다. 합성된 폴리에스터의 고유점도는 0.78∼1.2 dL/g으로 상용화된 poly(ethylene terephthalate)(PET) 와 비슷하였다. 다이올의 길이가 증가할수록 Young`s modulus와 strength는 낮아지고 elongation-to-break는 높아지는 경향을 확인하였다. 합성한 poly(ethylene furandicarboxylate)(PEF)의 Young`s modulus는 3551 MPa, strength는 103 MPa로 상용화된 PET와 비슷하였다. Furan-2,5-dicarboxylic acid (FDCA) was synthesized by KMnO4 oxidation of 2,5-dihydroxymethylfuran( DHMF) derived from biomass. Polyesters were synthesized by esterification and polycondensation of FDCA with various diols(ethane-1,2-diol, propane-1,3-diol, butane-1,4-diol, hexane- 1,6-diol, decane-1,10-diol). The composition of polyesters was characterized by using 1H NMR. Thermal properties of the polyesters were characterized by DSC and TGA. Intrinsic viscosities(IV) of the polyesters were measured to be 0.78∼1.2 dL/g comparable with IV of commercial poly(ethylene terephthalate)(PET). As the chain lengths of diols increased, Young`s modulus and strength decreased and elongation-to-break generally increased. Young`s modulus and strength of the polyesters were measured to be 3551 MPa and 103 MPa, respectively, comparable with commercial PET.

A STUDY ON THE RISK PROTECTION OF THE MOLD TRANSFORMER

Chung,Young-Ki,Jung,Jong-Wook,Kim,Jae-Chul,Kwak,Hee-Ro,Lee,Su-Kyung 한국화재소방학회 1997 한국화재소방학회 학술대회 논문집 Vol.1997 No.-

This paper investigates and analyzes the installation and failure status of mold transformer being used in domestic subways and describes the extinguishing process by time through the combustion test of winding part of mold transformer. Condition of installed mold transformers and classes of fire were surveyed and the mold transformer was burned in a horizontal heating furnace. It was confirmed that the mold transformer is self extinguishing and nonflammability. According to this results, the suitable standard of fire protection for the mold transformer was demanded after review of domestic and abroad law. It is expected that the cost of fire protection equipment can be reduced by using the status and combustion test result of mold transformer.

Contribution of stress and coping strategies to problematic Internet use in patients with schizophrenia spectrum disorders

Lee, Ju-Yeon,Chung, Young-Chul,Song, Je-Heon,Lee, Yo-Han,Kim, Jae-Min,Shin, Il-Seon,Yoon, Jin-Sang,Kim, Sung-Wan Elsevier 2018 Comprehensive psychiatry Vol.87 No.-

<P><B>Abstract</B></P> <P><B>Introduction</B></P> <P>Internet use is already high and increasing rapidly among people with psychotic disorders, but there have been few studies on problematic Internet use (PIU) among patients with schizophrenia spectrum disorders. This study aimed to measure the prevalence of PIU and identify the factors associated with PIU among patients with schizophrenia spectrum disorders.</P> <P><B>Methods</B></P> <P>A cross-sectional survey was performed that included 368 outpatients with schizophrenia spectrum disorders: 317 with schizophrenia, 22 with schizoaffective disorder, 9 with schizophreniform disorder, and 20 with other schizophrenia spectrum and psychotic disorders. The severity of psychotic symptoms and levels of personal and social functioning were assessed by the Clinician-rated Dimensions of Psychosis Symptom Severity (CRDPSS) scale and the Personal and Social Performance (PSP) scale, respectively. PIU was evaluated using Young's Internet Addiction Test (IAT). Additionally, the Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS), Rosenberg Selfesteem Scale (RSES), and Brief Coping Orientation to Problems Experienced (COPE) Inventory were administered.</P> <P><B>Results</B></P> <P>PIU was identified in 81 (22.0%) of the 368 patients with schizophrenia spectrum disorders. Subjects with PIU were significantly younger and more likely to be male. Scores on the HADS, PSS, and dysfunctional coping dimension of the Brief COPE Inventory were significantly higher, and RSES scores were significantly lower, in the PIU group. Logistic regression analysis indicated that PIU in patients was significantly associated with scores on the PSS and dysfunctional coping dimension of the Brief COPE Inventory.</P> <P><B>Conclusions</B></P> <P>Patients with schizophrenia spectrum disorders and PIU were significantly more likely to have high levels of perceived stress and dysfunctional coping strategies. Patients with schizophrenia spectrum disorders who also engage in PIU may benefit from interventions that help them to develop appropriate skills for coping with stress.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Patients with schizophrenia spectrum disorders showed a high prevalence (22.0%) of problematic internet use (PIU). </LI> <LI> High levels of perceived stress rather than psychopathology itself contributes to the development of PIU in stabilized patients with schizophrenia. </LI> <LI> Our results indicate that managing stress and developing coping strategies are important for the prevention of PIU among this group of patients. </LI> </UL> </P>

Tungtungmadic Acid Isolated from Salicornia herbacea Suppresses the Progress of Carbon Tetrachloride-induced Hepatic Fibrosis in Mice

Chung, Young-Chul,Choi, Jae-Ho,Oh, Kyo-Nyeo,Chun, Hyo-Kon,Jeong, Hye-Gwang Korean Society of ToxicologyKorea Environmental Mu 2006 Toxicological Research Vol.22 No.3

Tungtungmadic acid(3-caffeoyl, 4-dihydrocaffeoyl quinic acid: CDCQ) is a new chlorogenic acid derivative isolated from the Salicornia herbacea. The suppressive effects of CDCQ on the progress of acute carbon tetrachloride($CCl_4$)-induced hepatic fibrosis were investigated in mice. CDCQ significantly suppressed $CCl_4$-induced hepatic necrosis and inflammation, as determined by serum enzymatic activities of alanine and aspartate aminotransferase and serum TNF-$\alpha$ levels in a dose-dependent manner. In addition, increased hepatic lipid peroxidation and fibrosis after acute $CCl_4$ treatment were suppressed by the administration of CDCQ. CDCQ also significantly prevented the elevation of hepatic hydroxyproline and collagen content and ${\alpha}$-smooth muscle actin(${\alpha}$-SMA) expression in the liver of $CCl_4$-intoxicated mice. These results suggest that the suppressive effects of CDCQ against the acute $CCl_4$-induced hepatic fibrosis possibly related to its ability to block both hepatic inflammation and the activation of hepatic stellate cells.

Molecular Cloning and Expression of Cellulase of Gene of Pseudomonas sp. in Escherichia coli

Chung, Young Chul,Kim, Yang Woo,Kang, shin Kwon,Rho, Jong Su,Sung, Nack Kie 한국산업미생물학회 1990 한국미생물·생명공학회지 Vol.18 No.6

Cellulase 복합체와 xylanase를 동시에 분비하는 Pseudomonas sp. LBC 505와 CYC 10의 cellulase 유전자를 pUC19를 사용하여 E. coli에 클로닝시켰다. Congo red 염색시 노란색 환을 형성하는 대장균 형질전환체에서 0.7kb-와 4.6kb-HindⅢ 단편을 함유한 재조합 플라스미드 pLC1과 pLC2를 각각 분리하였다. DNA hybridization 실험에서 pLC1과 pLC2는 Pseudomonas sp. LBC 505와 CYC 10 유래임이 각각 밝혀졌고, lmmunoassay 실험에서도 유사성이 인정되었다. pLC1을 함유하고 있는 대장균은 cellulase의 24%를 세포외로 분비하였고, 효소활성은 모균주에 비해 1.4배 증가하였다. pLC1과 pLC2의 효소학적 성질도 모균주와 동일하였으며, 기질특이성과 HPLC로 유리당을 분석한 결과, 클로닝된 유전자는 endo type인 것으로 나타났다. The genes for cellulases of Pseudomonas sp. LBC505 and CYC10, potent cellulase complex-producing strains, were cloned in Escherichia coli with pUC19. Recombinant plasmids pLC1 and pLC2 were isolated from transformants producing cellulase by congo red staining, and their genes cloned were 0.7 kb and 4.6 kb HindⅢ fragments, respectively. The inserts of pLC1 and pLC2 were hybridized to chromosomal DNAs digested with HindⅢ from Pseudomonas sp. LBC505 and CYC10, respectively. Immunodiffusion assays revealed that pLC1-and pLC2-encoded cellulase showed similarity with that of host strains. About 24% of cellulase activity was observed in the extracellular fraction of E. coli carrying pLC1, and its activity was higher about 1.4 times than that of LBC505. The enzymatic properties of pLC1 and pLC2 encoded cellulase were the same as those of cellulase from host strains. HPLC analysis and substrate specificity showed that cellulases were the same as those of cellulase from host strains. HPLC analysis and substrate specificity showed that cellulases cloned were endocellulase.

Validation of the Korean version of the Eppendorf Schizophrenia Inventory as a screening measure to detect adolescents at ultra-high risk for psychosis.

Chung, Young-Chul,Kang, Nam-In,Im, Yong-Jin,Kim, Sung-Wan,Cho, In Hee,Lee, Young Moon,Kwon, Jun Soo Blackwell Publishing Asia 2013 Early intervention in psychiatry Vol.7 No.1

<P>No validated self-report scale is available for use as a screening tool to detect non-help-seeking adolescents at ultra-high risk (UHR) for psychosis in a community setting. The study aims to examine the reliability and validity of the Korean version of the Eppendorf Schizophrenia Inventory (K-ESI) for assessing adolescents at UHR for psychosis in a community setting.</P>

SOCIETY IN DISARRAY: CRIME, CORRUPTION AND DEEPENING COGNITIVE DISSONANCE IN NORTH KOREA

Chung Young Chul 동아시아재단 2009 Global Asia Vol.4 No.2

Second run of transcranial magnetic stimulation has no effects on persistent auditory hallucinations

Chung, Young-Chul,Im, Eun-Sung,Cho, Gwang-Hyun,Ko, Myung-Hwan Informa Healthcare 2007 The world journal of biological psychiatry Vol.8 No.1

<P> We report the case of a 30-year-old male schizophrenic patient with persistent auditory hallucinations (AHs) who had received two 1-Hz transcranial magnetic stimulations (TMS) to the left temporoparietal cortex. The patient had suffered from severe persistent AHs for more than 5 years with little improvement in response to various types of combination pharmacotherapy of antipsychotics. Upon commencement of TMS, however, the patient reported substantial improvement by the end of the third week of the treatment. The patient was discharged, but readmitted 6 months later because his AHs returned to their initial severity. A second run of TMS had no therapeutic effect. Further research is needed to establish the therapeutic duration of TMS treatment and to assess whether the second run of TMS after AH reoccurrence has therapeutic benefits.</P>

Differentiation of Benign and Malignant Solid Pseudopapillary Neoplasms of the Pancreas

Chung, Yong Eun,Kim, Myeong-Jin,Choi, Jin-Young,Lim, Joon Seok,Hong, Hye-Suk,Kim, Young Chul,Cho, Hyeon Je,Kim, Kyung Ah,Choi, Sun Young Lippincott Williams Wilkins, Inc. 2009 Journal of computer assisted tomography Vol.33 No.5

OBJECTIVE:: The aim of this study was to investigate differential imaging features between benign and malignant solid pseudopapillary neoplasms (SPN) of the pancreas on computed tomographic and magnetic resonance imagings. METHODS:: Between January 2001 and January 2007, we identified 30 patients with confirmed SPN by surgery. The computed tomographic and magnetic resonance images were reviewed by 3 radiologists in consensus. Each tumor was analyzed for the following categories: location of tumor, tumor margin, proportion of solid component, morphology of capsule, growth pattern, calcification, and presence of upstream pancreatic ductal dilatation. RESULTS:: Benign SPN usually had oval/round or smoothly lobulated margins, and malignant SPN more commonly had focal lobulated margins (P = 0.027). Presence of complete encapsulation was more frequently seen in benign SPN, whereas focal discontinuity of capsule was more commonly seen in malignant SPN (P = 0.005). There was no statistical difference between benign and malignant tumors in other imaging findings. CONCLUSIONS:: A focal lobulated margin and a focal discontinuity of the capsule may suggest malignant SPN, whereas a round or smoothly lobulated margin and a complete encapsulation were more commonly seen in benign SPN.

Elevated Levels of Inflammatory and Vasoactive Factors in the Culprit Coronary Artery of Acute Myocardial Infarction

( Young Guk Ko ),( Jae Hun Jung ),( Sung Ha Park ),( Eui Young Choi ),( Bo Young Joung ),( Ki Chul Hwang ),( Dong Hoon Choi ),( Yang Soo Jang ),( Nam Sik Chung ),( Won Heum Shim ),( Seung Yun Cho ) 한국조직공학과 재생의학회 2006 조직공학과 재생의학 Vol.3 No.3

Distal embolization of the thrombus and plaque debris, as well as the release of inflammatory and vasoactive factors are suggested as important factors that may jeopardize successful myocardial reperfusion during primary coronary intervention. However, there are currently few clinical data on the presence and the role of such factors. We performed in 18 acute myocardial infaction patients primary percutaneous coronary intervention(PCI) with the distal protection device of distal occlusive balloon type, PercuSurge GuideWire system. We collected blood samples from the femoral artery before PCI and from culprit coronary artery using Export aspiration catheter after predilation while inflating the distal protection balloon and after completing PCI with deflation of the distal protection balloon. We determined concentrations of C-reactive protein, soluble CD40 ligand, IL-6, serotonin, tissue factor, and factor VIIa inblood samples. The concentrations of soluble CD40 ligand(2.84±3.74 vs 0.98±0.63 ng/mL, p= 0.004), IL-6(33.67±32.63 vs 17.08±21.41 pg/mL, p<0.001), serotonin(2.05±0.76 vs 0.92±0.60 ng/mL, p<0.001), tissue factor (257.17±84.34 vs 154.60±87.99 pg/mL, p<0.001) and factor VIIa(34.30±27.30 vs 24.19±28.00 ng/mL, p=0.016) were significantly higher in the culprit coronary artery after the first predilation than those in the peripheral blood before PCI. However, the CRP concentrations in the samples from the culprit coronary artery and the femoral artery did not differ significantly(4.15±3.19 vs 4.60±3.68 mg/L, p=0.056). The blood samples from coronary artery after multiple aspirations showed reduced concentrations of soluble CD40 ligand(2.84±3.74 to 1.64±1.96 ng/mL, p=0.030), IL-6(33.67±32.63 to 22.44±21.87 ng/mL, p=0.010), serotonin(2.05±0.76 to 1.29±0.82 ng/mL, p<0.001), tissue factor(257.17±84.34 to 198.45±95.14 ng/mL, p=0.001) and factor VIIa(34.30±27.30 to 27.65±27.24 ng/mL, p=0.001) compared to those in the coronary aspirates obtained after first balloon dilation of the culprit lesions. We found increased levels of soluble inflammatory and vasoactive factors such as soluble CD40 ligand, IL-6, serotonin, tissue factor and factor VII in the aspirate from the culprit coronary artery compared to those in peripheral blood. The aspiration of blood from culprit lesion during PCI resulted in significantly reduced concentrations of inflammatory and vasoactive markers.