Single‐Molecule Four‐Color FRET

Lee ,, Jinwoo,Lee ,, Sanghwa,Ragunathan, Kaushik,Joo, Chirlmin,Ha, Taekjip,Hohng, Sungchul WILEY‐VCH Verlag 2010 Angewandte Chemie Vol.122 No.51

<P><B>Sechs FRET‐Interfluorophoreffizienzen</B> <I>E</I><SUB><I>ij</I></SUB> (siehe Schema) wurden in Echtzeit durch eine Einzelmolekül‐Vierfarben‐FRET‐Technik mittels konfokaler Mikroskopie sowie Fluoreszenzmikroskopie mit interner Totalreflexion bestimmt. Das Verfahren wurde verwendet, um die korrelierte Bewegung der vier Arme der Holliday‐Junction und die Korrelation von RecA‐vermittelten Strangaustauschereignissen an beiden Enden eines synaptischen Komplexes zu untersuchen.</P>

Improving physical realism, stereochemistry, and side‐chain accuracy in homology modeling: Four approaches that performed well in CASP8

Krieger, Elmar,Joo, Keehyoung,Lee, Jinwoo,Lee, Jooyoung,Raman, Srivatsan,Thompson, James,Tyka, Mike,Baker, David,Karplus, Kevin Wiley Subscription Services, Inc., A Wiley Company 2009 Proteins Vol.77 No.suppl9

<P>A correct alignment is an essential requirement in homology modeling. Yet in order to bridge the structural gap between template and target, which may not only involve loop rearrangements, but also shifts of secondary structure elements and repacking of core residues, high-resolution refinement methods with full atomic details are needed. Here, we describe four approaches that address this 'last mile of the protein folding problem' and have performed well during CASP8, yielding physically realistic models: YASARA, which runs molecular dynamics simulations of models in explicit solvent, using a new partly knowledge-based all atom force field derived from Amber, whose parameters have been optimized to minimize the damage done to protein crystal structures. The LEE-SERVER, which makes extensive use of conformational space annealing to create alignments, to help Modeller build physically realistic models while satisfying input restraints from templates and CHARMM stereochemistry, and to remodel the side-chains. ROSETTA, whose high resolution refinement protocol combines a physically realistic all atom force field with Monte Carlo minimization to allow the large conformational space to be sampled quickly. And finally UNDERTAKER, which creates a pool of candidate models from various templates and then optimizes them with an adaptive genetic algorithm, using a primarily empirical cost function that does not include bond angle, bond length, or other physics-like terms.</P>

조리 방법에 따른 고구마줄기의 Phytochemical 함량과 항산화 활성 비교

양세희, 정혜진, 성예지, 이하나, 이세윤, 양진우, 이준수 忠北大學校 農業科學硏究所 2017 農業科學硏究 Vol.33 No.1

Vegetable consumption is associated with health benefits. Recently, the interest in these food groups has grown among due to the identification of new compound in their chemical composition. Most of the vegetables are cooked by blanching, boiling, steaming, microwaving before consumed. These cooking processes may change not only food physical characteristics but also chemical composition. The present study was undertaken to investigate the effect of different cooking methods on phytochemical content and antioxidant capacity in Ipomoea batatas (L.) Lam stem. The result of study, Total polyphenol of phytochemical in Ipomoea batatas (L.) Lam stem was 6.88-12.65 mg GAE/100 g and flavonoid was 3.16-10.46 mg CE/100 g. Compared with the raw of Ipomoea batatas (L.) Lam stem, all cooking methods were found to significant correlations between the antioxidant activity assessed by ABTS, DPPH and polyphenol(p<0.05). These results can be provide the basic data how to prevent lose of nutrition in Ipomoea batatas (L.) Lam stem when cooking.

Synthesis of carbon nanotube fibers from carbon precursors with low decomposition temperatures using a direct spinning process

Lee, Sung-Hyun,Kim, Hye-Rim,Lee, Taeseon,Lee, Haemin,Lee, Jinwoo,Lee, Jaegeun,Park, Junbeom,Lee, Kun-Hong Elsevier 2017 Carbon Vol.124 No.-

<P>Carbon nanotube (CNT) fibers were synthesized from ethylene, acetylene, or methane by separately injecting ferrocene and the carbon precursors during a direct spinning process. Ethylene and acetylene have low decomposition temperatures. It was difficult to synthesize CNT fibers from these precursors using the direct spinning method. CNT fibers were continuously synthesized by delaying the contact time between the catalyst particles and the carbon precursors, which provided sufficient time for catalyst growth. Changes in catalyst size from 2 nm to 20 nm were observed as a function of the catalyst formation step setting temperature (350-440 degrees C) and the carbon precursor injection tube length (8-310 mm), and the relationship between the catalyst size and the CNT diameter was characterized. The CNT fibers had higher I-G/I-D ratios when synthesized from acetylene (69.87) or ethylene (18.52) than from methane (3.61). The choice of the carbon precursor had a much larger effect on the I-G/I-D ratio of the synthesized CNT fibers than the other operating variables. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Analysis of Fifty Hotspot Mutations of Lung Squamous Cell Carcinoma in Never-smokers

Lee, Ha Youn,Lee, Se-Hoon,Won, Jae-Kyung,Lee, Dong Soo,Kwon, Nak-Jung,Choi, Sun Mi,Lee, Jinwoo,Lee, Chang-Hoon,Lee, Sang-Min,Yim, Jae-Joon,Yoo, Chul-Gyu,Kim, Young Whan,Han, Sung Koo,Park, Young Sik KOREAN ACADEMY OF MEDICAL SCIENCE 2017 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.32 No.3

<P>Smoking is the major risk factor for lung squamous cell carcinoma (SCC), although a small number of lung SCCs occurs in never-smokers. The purpose of this study was to compare 50 hotspot mutations of lung SCCs between never-smokers and smokers. We retrospectively reviewed the medical records of patients newly diagnosed with lung SCC between January 1, 2011 and December 31, 2013 in the Seoul National University Hospital. Formalin-fixed, paraffin-embedded tumor samples were used for analysis of hotspot mutations. Fifty cancer-related genes in never-smokers were compared to those in ever-smokers. Of 379 lung SCC patients, 19 (5.0%) were never-smokers. The median age of these 19 patients was 67 years (interquartile range 57–73 years), and 10 of these patients were women (52.5%). The incidence rates of stage I, II, III, and IV disease in this group were 26.4%, 5.3%, 31.6%, and 36.8%, respectively, and sequencing was performed successfully in 14 cases. In the 26 lung SCC tumor samples (12 from never-smokers and 14 from ever-smokers) sequenced using personal genome machine, the most common mutations were in <I>TP53</I> (75.0%), <I>RAS</I> (66.7%), and <I>STK11</I> (33.3%), but mutations were also found in <I>EGFR</I>, <I>KIT</I>, and <I>PTEN</I>. The distribution of hotspot mutations in never-smokers was similar to that in ever-smokers. There was no significant difference in overall survival between the 2 groups. The 50 hotspot mutations of lung SCC in never-smokers were similar to those of ever-smokers.</P>

Quality Assessment of Protein Models

Jinwoo Lee,Keehyoung Joo,Inho Lee,Jooyoung Lee 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.2009 No.5

Quality assessment (QA) is to judge the quality of a protein model without knowing its native structure. It plays an important role in the process of protein structure prediction by guiding us to select an appropriate combination of templates out of many possibilities [1]. We formulate the QA problem as mapping and regression. Protein models are mapped into R<SUP>n</SUP> space by extracting n features from each model, and the space is divided into subspaces according to the feature values in order to represent models’ closeness (between 0 and 1) to the native structure. For the feature values, we measure the degree of agreement between the predicted property from the sequence analysis and the calculated one from the 3D model. Properties that we use include the secondary structure, solvent accessibility, hydrophobicity, and energy components from MODELLER [2], DFIRE [3], and TASSER [4]. One advantage of using the consensustype feature is that models with similar quality are prone to be clustered together in R<SUP>n</SUP> space, and thus they tend to be well classified. Assigning closeness values to regions of R<SUP>n</SUP> space is carried out using decoy structures generated during the CASP7 with known native structures [1] by applying Support Vector Machine regression techniques (SVM). SVM that we used has the character of non-linearity which can be applied to the linearly non-separable cases. In other words, for given features, SVM is more efficient than the linear method such as linear programming. The proposed method was used to select final models during the CASP8 prediction. We will discuss both the usefulness and the limitation of the method for better protein modeling.

Rapid Sonochemical Synthesis of Spherical-shaped Mesoporous SBA-15 silica and Ti-incorporated SBA-15 Silica Materials

Lee, SeonKeun,Lee, Jinwoo,Joo, Jin,Hyeon, Taeghwan,Ahn, WhaSeung,Lee, Ho-In,Lee, Chung-Hak,Choi, Wonyong 한국공업화학회 2003 Journal of Industrial and Engineering Chemistry Vol.9 No.1

Mesoporous SBA-15 silica materials were synthesized in short time from one hour ultrasonic irradiation, followed by 1~3 h gelation in acidic media. The particle morphology of these sonochemically synthesized mesoporous materials was nearly spherical. Titanium was directly incorporated into SBA-15 silicate framework through sonochemical co-condensation of Ti(0-iPr)4 and Si(OEt)4. The Ti-incorporated SBA-15 silica exhibited good catalytic activity for the oxidation of 2,6-di-tert-butylphenol.

Magnetically-separable and highly-stable enzyme system based on crosslinked enzyme aggregates shipped in magnetite-coated mesoporous silica

Lee, Jinwoo,Na, Hyon Bin,Kim, Byoung Chan,Lee, Jin Hyung,Lee, Byoungsoo,Kwak, Ja Hun,Hwang, Yosun,Park, Je-Geun,Gu, Man Bock,Kim, Jaeyun,Joo, Jin,Shin, Chae-Ho,Grate, Jay W.,Hyeon, Taeghwan,Kim, Jungb Royal Society of Chemistry 2009 Journal of materials chemistry Vol.19 No.42

<P>A magnetically-separable and highly-stable enzyme system was developed by adsorption of enzymes in superparamagnetic hierarchically ordered mesocellular mesoporous silica (M-HMMS) and subsequent enzyme crosslinking. Superparamagnetic nanoparticles were homogeneously incorporated into hierarchically-ordered mesocellular mesoporous silica (HMMS) by the decomposition of a preformed iron propionate complex. The size of the incorporated superparamagnetic nanoparticles was around 5 nm, generating a magnetically separable host with high pore volumes and large pores (M-HMMS). α-chymotrypsin (CT) was adsorbed into M-HMMS with high loading (∼30 wt%) in less than 30 minutes. Glutaraldehyde (GA) treatment of adsorbed CT resulted in nanometer scale crosslinked enzyme aggregates in M-HMMS (CLEA-M). The activity of these CT aggregates in M-HMMS (CLEA-M-CT) was 34 times than that of simply adsorbed CT in M-HMMS, due to an effective prevention of enzyme leaching during washing <I>via</I> a ship-in-a-bottle approach. CLEA-M-CT maintained the initial activity not only under shaking (250 rpm) for 30 days, but also under recycled uses of 35 times. The same approach was employed for the synthesis of CLEA-M of lipase (CLEA-M-LP), and proven to be effective in improving the loading, activity, and stability of enzyme when compared to those of adsorbed LP in M-HMMS.</P> <P>Graphic Abstract</P><P>Crosslinked enzyme aggregates in magnetitie-coated mesoporous silica, fabricated <I>via</I> a two-step procedure of enzyme adsorption and crosslinking, were highly active, highly stable, and easily recyclable using a magnet. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b909109b'> </P>

Highly Controlled Nanoporous Ag Electrode by Vaporization Control of 2-Ethoxyethanol for a Flexible Supercapacitor Application

Lee, Jinwoo,Lee, Jaehak,Kwon, Jinhyeong,Lee, Habeom,Eom, Hyeonjin,Yoon, Yeosang,Ha, Inho,Yang, Minyang,Ko, Seung Hwan American Chemical Society 2017 Langmuir Vol.33 No.8

<P>Controlling the surface morphology of the electrode on the nanoscale has been studied extensively because the surface morphology of a material directly leads to the functionalization in various fields of studies. In this study, we designed a simple and cost-effective method to fine-tune the surface morphology and create controlled nanopores on the silver electrode by utilizing 2-ethoxyethanol and two successive heat treatments. High electrical conductivity and mechanical robustness of nanoporous silver corroborate its prospect to be employed in various applications requiring a certain degree of flexibility. As a proof-of-concept, a high-performance supercapacitor was fabricated by electrodepositing MnO2. This method is expected to be useful in various electronic applications as well as energy storage devices.</P>

A Case of Acute Pulmonary Thromboembolism after Taking Tadalafil

Lee, Jinwoo,Kwon, Ji Hyun,Lee, Chang-Hoon,Lee, Sang-Min,Yim, Jae-Joon,Yoo, Chuy-Gyu,Kim, Young Whan,Han, Sung Koo,Park, Young Sik The Korean Academy of Tuberculosis and Respiratory 2012 Tuberculosis and Respiratory Diseases Vol.73 No.4

Tadalafil is a phosphodiesterase-5 inhibitor (PDE5I), which is widely used to treat erectile dysfunction. Although PDE5Is have excellent safety profiles, and most of the side effects are mild, rare serious adverse events have been reported in association with PDE5Is. Thrombosis is one of those events, and a few previous reports have suggested the association of PDE5Is with thrombosis. We report the case of a 61-year-old male who developed pulmonary embolism combined with pulmonary infarction directly after taking tadalafil. Both the patient and the physician suspected tadalafil as the culprit drug, as the patient was in an otherwise healthy condition. However, after extensive evaluation, we noticed that factor VIII levels were elevated. Prior reports suggesting the association between thrombosis and PDEIs either lack complete information on coagulation factors, or show inconsistencies in their results. Physicians should operate caution prior to accepting the diagnosis of adverse drug reaction.