Immobilization of Lactobionic Acid on Polyurethane Films and Their Interaction with Hepatocytes

Meng Wan,Jung Kyung-Hye,Kang Inn-Kyu,Kwon Oh Hyeong,Akaike Toshihiro The Polymer Society of Korea 2005 Macromolecular Research Vol.13 No.3

Polyurethanes containing z-Iysine segments in the main chain (PULL) were synthesized from 4,4'-diphe-nylmethyl diisocyanate, poly(tetramethylene glycol), and z-Iysine oligomer as a chain extender. The PULL film was treated first with a $10\%$ HBr-acetic acid solution and subsequently with a saturated sodium bicarbonate aqueous solution to produce a primary amine group on the surface (PULL-N). Lactobionic acid (LA)-immobilized PULL (PULL-L) was prepared by the coupling reaction of the PULL surface amine groups and the LA carboxylic acid groups. The surface-modified PULLs were then characterized by attenuated total reflection-Fourier transform infra-red spectroscopy, electron spectroscopy for chemical analysis, atomic force microscopy, and contact angle goniometry. In the hepatocytes adhesion experiment, the cells poorly adhered to the PULL surface, although they adhered moderately well to the PULL-N surface. On the other hand, the cells adhered well to the PULL-L surface, suggesting the good affinity of the surface $\beta$-galactose moieties for hepatocytes. When hepatocytes were cultured in the presence of epidermal growth factor for 48 h, the cells rapidly aggregated on the PULL-L surface, whereas they aggregated only slowly on the other surfaces. The PULL prepared in this study has the potential to be used as a coating material for the enhancement of hepatocyte adhesion.

Preparation of PHBV/Collagen Nanofibrous Mats and their Tissue Compatibility Compatibilscaffolds for Tissue Engineering

Wan Meng,Se-Yong Kim,Jiang Yuan,Jung Chul Kim,Oh Hyeong Kwon,Yoshihiro lto,Inn-Kyu Kang 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.10

PHBV의 표면개질 및 간세포와의 상호작용

Wan Meng,강인규,손한규 한국생체재료학회 2003 생체재료학회지 Vol.7 No.1

Poly(3-hydroxy butylate-co-3-hydroxy valerate) (PHBV, 34 mol% of hydroxy valerate) film was prepared by dissolving chloroform and casting on a glass plate. Acrylic acid-grafted PHBV (PHBV-C) and N-p-vinylbenzyl-O--D-galactopyranosyl-(1→4)-D-gluconamide (VLA)-grafted PHBV(PHBV-VLA) were prepared by the treatment of PHBV film with oxygen plasma, followed by the graft polymerization of acrylic acid (AA) and VLA, respectively. Collagen-immobilized PHBV was also prepared by the coupling reaction of PHBV-C and collagen using water soluble carbodiimide (WSC). Surface characterization of modified PHBVs were carried out using electron spectroscopy for chemical analysis (ESCA), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and contact angle goniometer. Attachment and morphology of mouse hepatocytes on surface-modified PHAs were investigated using 3-(4,5-dimethyl thiazo l-2-yl)-2,5-diphenyltetrazolium (MTT) method and light microscope. Amounts of AA, collagen, and VLA introduced to the PHBV film surfaces as determined by gravimetric method were about 38, 78, and 12 g/cm2, respectively. Amount of hepatocytes adhered to PHBV-COL and PHBV-VLA were significantly larger than those to PHBV and PHBV-C, showing specific interaction of surface VLA groups with hepatocytes.

Electrospun PHBV/collagen composite nanofibrous scaffolds for tissue engineering

Meng, Wan,Kim, Se-Yong,Yuan, Jiang,Kim, Jung Chul,Kwon, Oh Hyeong,Kawazoe, Naoki,Chen, Guoping,Ito, Yoshihiro,Kang, Inn-Kyu Informa UK (TaylorFrancis) 2007 Journal of Biomaterials Science. Polymer Edition Vol.18 No.1

<P>Electrospinning has recently emerged as a leading technique for the formation of nanofibrous structures made of synthetic and natural extracellular matrix components. In this study, nanofibrous scaffolds were obtained by electrospinning a combination of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and type-I collagen in 1,1,1,3,3,3-hexafluoro-2-isopropanol (HIFP). The resulting fibers ranged from 300 to 600 nm in diameter. Their surfaces were characterized by attenuated total reflection Fourier transform infrared spectroscopy, electron spectroscopy for chemical analysis and atomic force microscopy. The PHBV and collagen components of the PHBV/collagen nanofibrous scaffold were biodegraded by PHB depolymerase and a type-I collagenase aqueous solution, respectively. The cell culture experiments indicated that the PHBV/collagen nanofibrous scaffold accelerated the adhesion and growth of NIH3T3 cells more effectively than the PHBV nanofibrous scaffold, thus making the former a good scaffold for tissue engineering.</P>

Synthesis of Block Copolymers Consisting gof Polyoxypropylene and Poly(ε-benzyloxycarbonyl L-lysine) and their Blood Compatibility

Wan Meng,권오형,강인규,현재영,Xinglin Guo,조얼령 한국생체재료학회 2002 생체재료학회지 Vol.6 No.2

A-B-A type block copolymers were prepared by the polymerization of (-benzyloxycarbonyl L-lysine N-carboxyanhydride) (A segment) using amino-terminated polyoxypropylene (POP, B segment) as an initiator. The morphology of the block copolymers showed POP domains dispersed in the poly(-benzyloxycarbonyl L-lysine) (PBCL) matrix. Water contact angles of films of the block copolymer were almost same as that of the surface of PBCL film. Upon acid treatment of the block copolymer films, water contact angles decreased. Thrombus formation on block copolymer films was minimum for a POP content of 29 mol%. Identical results were obtained from a blood clotting test. The number of platelets adhered to the bulk and the surface-modified block copolymers was almost equal. However, serotonins were less released from the platelets adhered on the PL-2 block copolymer and surface-modified block copolymers (MPL-1, MPL-2, MPL-3).

인슐린을 고정화한 폴리우레탄 막의 제조 및 섬유아세포와의 상호작용

맹만(Wan Meng),김우식(Woo Sik Kim),이동호(Dong Ho Lee),박이순(Lee Soon Park),강인규(Inn Kyu Kang) 한국고분자학회 2004 폴리머 Vol.28 No.6

Effect of bio-template on the properties of SiO2/Al2O3 composites for drug delivery

Long-Yue Meng,Weiqi Jiang,Wen Xiang Piao,Wan Meng 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.37 No.-

In this study, SiO2/Al2O3 composites (C-SLNs) were successfully synthesized using chitosan as thetemplate for drug delivery. The C-SLNs had higher specific surface areas (244–607 m2/g), total porevolumes (0.19–0.34 cm3 g 1), and narrow mesopore size distribution. The porosity of the C-SLNsprepared under high Si/Al ratio conditions was achieved mostly by the formation of wider pores thatwere distributed in the meso-/macro-pores. And, the C-SLNs were used as a levofloxacin carrier to studyits drug release behavior, which exhibited an initial fast release followed by a sustained release andantibacterial effectiveness over a long period.

Slide Session : OS-GAS-05 ; Gastroenterology : 3-Mercaptopyruvate Sulfurtransferase Downregulation Ameliorates Hepatic Steatosis and Oxidative Stress Via Hydrogen Sulfi de Metabolism in Nonalcoholic Fatty Liver Disease

( Meng Li ),( Jiexia Ding ),( Xingyong Wan ),( Xi Jin ),( Shaohua Chen ),( Chaohui Yu ),( Youming Li ) 대한내과학회 2014 대한내과학회 추계학술발표논문집 Vol.2014 No.1

Background: The mitochondrial enzyme 3-mercaptopyruvate sulfurtransferase (MPST) is a source of endogenous hydrogen sul.de (H2S), a gaseous signaling molecule implicated in a wide range of physiological processes. The mechanisms of pathogenesis underlying nonalcoholic fatty liver disease (NAFLD) remain unclear. The possible role of MPST in the development of NAFLD has never been investigated. Methods: The NAFLD cell model was established by treating L02 cells with free fatty acid (FFA) overload. A variety of cellular and molecular approaches were used to study the effects of MPST on hepatic steatosis, oxidative stress and inflammation involved in NAFLD. Results: After culturing L02 cells by FFA for 24h, we detected the increased protein level of MPST. MPST knockdown in L02 cells resulted in a marked decrease of lipid accumulation and downregulation of SREBP-1 pathway and melioration of oxdiative stress, embodied in decreased level of H2O2, MDA and IL-6, meanwhile, increased levels of ATP and MMP. Unexpectedly, we observed a significantly increased level of H2S after knockdown of MPST. And the expression of CSE was enhanced when the MPST was decreased. When the level of H2S was decreased, the TG and H2O2 content within FFA-induced hepatocytes were greatly raised. Meanwhile, we demonstrated the reversed expression of SREBP-1/ ACC pathway with the reduced level of H2S. Conclusions: We showed that MPST knockdown could stimulate the compensatory process of CSE, causing the increasing of H2S which is recently considered as a novel antioxidant gas. The increased endogenous H2S could improve hepatocyte steatosis and partly improve the process of oxidative stress and in. ammatory state of steatosis hepatocytes. MPST is implicated in NAFLD via its important H2S metabolism. It provided new insight into the pathogenic mechanisms of NAFLD, pointing to potential target for therapeutic strategy.

G.E. 레싱과 J.M. 괴쩨와의 단편 논쟁

맹주완 한국헤세학회 2003 헤세연구 Vol.10 No.-

1. 「Von Verschreiung der Vernunft von den Kanzeln」 2. 「Unmoglichkeit einer Offenbarung, die alle Menschen auf eine gegrundete Art glauben konnten」 3. 「Durchgang der Israeliten durchs Rote Meer」 4. 「Daβ die bucher des AT nicht geschrieben worden, eine Religion zu offenbaren」 5. 「Uber die Auferstechungsgeschichte」 Hayptpastor Goeze schaltet sich erstmalig am 17. Dezember 1777 in den Streit ein. Lessing antwortet hinfort auf die Angriffe des Hauptpastors Goeze gegen den Ungenannten mit dem Titel: 「Anti-Goeze」. Der Lessing Goeze-Streit wird aber durch herzoglichen Erlass gewaltsam beendet. Am 6. Juli wird Lessing der weitere Druck und Vertrib der Beitrage verboten. Die grundlegenden Differenzen des Goeze-Lessing-Streits gab es wegen des Verstandnises der Religion bzw. der Bibel. Lessing schrieb einmal Folgendes: "Die Wunder, die Christus und seine Junger taten, waren das Geruste, und nicht der Bau. Das Geruste wird abgerissen, sobald der Bau vollendet ist." Goeze dagegen insistierte auf einem am Buchstablichen ausgerichteten Verstandnis: "Auf den Lehren und Taten Christi und der Apostel beruhet also die gesamte christliche Religion. Woher konnen wir nun diese Lehren und Taten wissen ? allein aus den Schriften der Evangelisten und Apostel."

Cocaine- and Amphetamine-Regulated Transcript (CART) Peptide Plays Critical Role in Psychostimulant-Induced Depression

Meng, Qing,Kim, Hyoung-Chun,Oh, Seikwan,Lee, Yong-Moon,Hu, Zhenzhen,Oh, Ki-Wan The Korean Society of Applied Pharmacology 2018 Biomolecules & Therapeutics(구 응용약물학회지) Vol.26 No.5

Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter expressed in the central nervous systems. Previously, several reports demonstrated that nucleus accumbal-injected CART peptide positively modulated behavioral sensitization induced by psychostimulants and regulated the mesocorticolimbic dopaminergic pathway. It is confirmed that CART peptide exerted inhibitory effect on psychostimulant-enhanced dopamine receptors signaling, $Ca^{2+}$/calmodulin-dependent kinase signaling and crucial transcription factors expression. Besides modulation of dopamine receptors-related pathways, CART peptide also exhibited elaborated interactions with other neurotransmitter receptors, such as glutamate receptors and ${\gamma}$-aminobutyric acid receptors, which further account for attribution of CART peptide to inhibition of psychostimulant-potentiated locomotor activity. Recently, CART peptide has been shown to have anxiolytic functions on the aversive mood and uncontrolled drug-seeking behaviors following drug withdrawal. Moreover, microinjection of CART peptide has been shown to have an antidepressant effect, which suggests its potential utility in the mood regulation and avoidance of depression-like behaviors. In this review, we discuss CART pathways in neural circuits and their interactions with neurotransmitters associated with psychostimulant-induced depression.