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Skin scarring after deep dermal injuries is a major clinical problem due to the current therapies limited to established scars with poor understanding of healing mechanisms. From investigation of aberrations within the extracellular matrix involved in pathophysiologic scarring, it was revealed that one of the main factors responsible for impaired healing is abnormal collagen reorganization. Here, inspired by the fundamental roles of decorin, a collagen-targeting proteoglycan, in collagen remodeling, we created a scar-preventive collagen-targeting glue consisting of a newly designed collagen-binding mussel adhesive protein and a specific glycosaminoglycan. The collagen-targeting glue specifically bound to type I collagen in a dose-dependent manner and regulated the rate and the degree of fibrillogenesis. In a rat skin excisional model, the collagen-targeting glue successfully accelerated initial wound regeneration as defined by effective reepithelialization, neovascularization, and rapid collagen synthesis. Moreover, the improved dermal collagen architecture was demonstrated by uniform size of collagen fibrils, their regular packing, and a restoration of healthy tissue component. Collectively, our natural healing-inspired collagen-targeting glue may be a promising therapeutic option for improving the healing rate with high-quality and effective scar inhibition.

Xenogenic bone substitutes are commonly used during orthopedic reconstructive procedures to assist bone regeneration. However, huge amounts of blood accompanied with massive bone loss usually increase the difficulty of placing the xenograft into the bony defect. Additionally, the lack of an organic matrix leads to a decrease in the mechanical strength of the bone-grafted site. For effective bone grafting, this study aims at developing a mussel adhesion-employed bone graft binder with great blood-resistance and enhanced mechanical properties. The distinguishing water (or blood) resistance of the binder originates from sandcastle worm-inspired complex coacervation using negatively charged hyaluronic acid (HA) and a positively charged recombinant mussel adhesive protein (rMAP) containing tyrosine residues. The rMAP/HA coacervate stabilizes the agglomerated bone graft in the presence of blood. Moreover, the rMAP/HA composite binder enhances the mechanical and hemostatic properties of the bone graft agglomerate. These outstanding features improve the osteoconductivity of the agglomerate and subsequently promote in vivo bone regeneration. Thus, the blood-resistant coacervated mussel protein glue is a promising binding material for effective bone grafting and can be successfully expanded to general bone tissue engineering.

Nanofibrous scaffolds have been assessed as one of many promising tissue engineering scaffolds to be utilized for wound-healing applications. Previously, we reported multi-functionalized electrospun nanofibrous scaffolds blended with mussel adhesive protein (MAP) and polycaprolactone (PCL), which provide durable mechanical strength, cell-friendly environments, and a substantial ability to capture diverse bioactive molecules without any surface modifications. In the present work, we applied the blended nanofibrous mats of MAP and PCL for in vivo skin wound healing. The nanofibrous mats showed accelerated regeneration in a rat skin wound-healing model, which might be attributed to a highly compatible environment for keratinocyte cell growth, an ability to capture inherent growth factors, and an efficient exudate absorption capacity. Thus, this work would suggest that adhesive property of scaffold could be a factor of successful application for wound healing. The MAP-blended nanofibers could also be potentially exploited for diverse tissue regeneration applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 218-225, 2017.

Recent adhesive technologies have focused on the development of high-quality and eco-friendly adhesives. Thus, there is a gradual shift from the currently used chemical-based adhesives toward harmless adhesives with improved quality and performance. Here, we evaluated the potential use of bacteria-produced recombinant mussel adhesive protein (MAP) as a harmless wood furniture adhesive. We formulated a MAP wood adhesive as an inclusion body type for economical preparation, and we confirmed its harmlessness through the non-detection of volatile organic compounds and heavy metals. The formulated MAP showed sufficiently strong bulk adhesive strength for the dried gluing of wood adherends. We also found that the formulated MAP wood adhesive exhibits robust adhesion in various environmental conditions, including open assembly times, incubation times, temperatures, and humidity levels. In summary, the developed recombinant MAP could be successfully used as a promising environmentally-friendly, harmless wood furniture adhesive.

Urinary fistulas, abnormal openings of a urinary tract organ, are serious complications and conventional management strategies are not satisfactory. For more effective and non-invasive fistula repair, fluid tissue adhesives or sealants have been suggested. However, conventional products do not provide a suitable solution due to safety problems and poor underwater adhesion under physiological conditions. Herein, we proposed a unique water-immiscible mussel protein-based bioadhesive (WIMBA) exhibiting strong underwater adhesion which was employed by two adhesion strategies of marine organisms; 3,4-dihydroxy-l-phenylalanine (DOPA)-mediated strong adhesion and water-immiscible coacervation. The developed biocompatible WIMBA successfully sealed ex vivo urinary fistulas and provided good durability and high compliance. Thus, WIMBA could be used as a promising sealant for urinary fistula management with further expansion to diverse internal body applications.

Implantable scaffolds mimicking the different physicochemical attributes of the extracellular matrix (ECM) in native bone matrix have been developed for stem cell transplantation as a tailored microenvironment to direct the desired osteogenic responses. However, current approaches for the engineering of bone constructs fail to recapitulate the dynamic regulatory features of bone development and homeostatic maintenance, restricting their clinical outcomes especially in the repair of large craniofacial bone defects that involve a hostile ischemic environment. Here, a sticky bone-specific artificial ECM (aECM) was proposed as a bioengineered bone niche capable of regenerating fully functional bone tissue. The dual functionalization of two chimeric mussel adhesive proteins (MAPs) fused with the cell adhesive Alg-Gly-Asp (RGD) peptide or the osteoinductive bone morphogenetic protein-2 (BMP-2) peptide promoted in vitro cellular behaviors and osteogenic commitments of adipose-derived stem cells (ADSCs) through the synergistic effects of two bioactive peptides in a matrix-bound manner. The chimeric MAP-based aECM induced remarkably accelerated bone tissue formation and promoted the construction of functional vascular networks with bone marrow (BM)-like compartments on an ADSC-laden collagen sponge within a calvarial defect. Thus, our multicomposite bone-specific aECM could be a promising therapeutic platform for further driving the clinical translation of stem cell-mediated bone therapies.

Limited regenerative capacity of the nervous system makes treating traumatic nerve injuries with conventional polymer-based nerve grafting a challenging task. Consequently, utilizing natural polymers and biomimetic topologies became obvious strategies for nerve conduit designs. As a bioinspired natural polymer from a marine organism, mussel adhesive proteins (MAPs) fused with biofunctional peptides from extracellular matrix (ECM) were engineered for accelerated nerve regeneration by enhancing cell adhesion, proliferation, neural differentiation, and neurite formation. To physically promote contact guidance of neural and Schwann cells and to achieve guided nerve regeneration, MAP was fabricated into an electrospun aligned nanofiber conduit by introducing synthetic polymer poly(lactic-co-glycolic acid) (PLGA) to control solubility and mechanical property. In vitro and in vivo experiments demonstrated that the multi-dimensional tactics of combining adhesiveness from MAP, integrin-mediated interaction from ECM peptides (in particular, IKVAV derived from laminin α1 chain), and contact guidance from aligned nanofibers synergistically accelerated functional nerve regeneration. Thus, MAP-based multi-dimensional approach provides new opportunities for neural regenerative applications including nerve grafting. STATEMENT OF SIGNIFICANCE: Findings in neural regeneration indicate that a bioinspired polymer-based nerve conduit design should harmoniously constitute various factors, such as biocompatibility, neurotrophic molecule, biodegradability, and contact guidance. Here, we engineered three fusion proteins of mussel-derived adhesive protein with ECM-derived biofunctional peptides to simultaneously provide biocompatibility and integrin-based interactions. In addition, a fabrication of robust aligned nanofiber conduits containing the fusion proteins realized suitable biodegradability and contact guidance. Thus, our multi-dimensional strategy on conduit design provided outstanding biocompatibility, biodegradability, integrin-interaction, and contact guidance to achieve an accelerated functional nerve regeneration. We believe that our bioengineered mussel adhesive protein-based multi-dimensional strategy would offer new insights into the design of nerve tissue engineering biomaterials.

Stem cell therapies are emerging regenerative treatments for ischemic and chronic diseases. Although high cell retention and prompt angiogenesis are prerequisites to improving efficacy, advancements have not yet been developed. Here, we proposed long-term surviving and angiogenesis-inducing stem cell with high cell retention thanks to fluid immiscible liquid micro-droplets bio-inspired by a glue modality 'complex coacervate' found in the sandcastle worm. Formed by the Coulombic force between polycationic MAP and polyanionic hyaluronic acid, the exploited coacervate micro-droplets enabled the encapsulation of stem cells. The underwater adhesiveness facilitated integrating the encapsulated stem cells onto various surfaces with impressive cell retention after facile injection. Stem cells encapsulated in the coacervate platform formed cell clusters capable of pre-adjusting to hypoxia by expressing hypoxia-inducible factor 1α (HIF-1α), increasing viability and reducing apoptosis under hypoxia and ischemia as well as normoxia. Interestingly, multipotent and angiogenic factors were significantly enhanced by HIF-1α expression. In the in vivo evaluation, the coacervate platform showed impressive angiogenesis with biocompatibility and long-term cell retention capacity with sustainable release as protein factories. Therefore, the proposed MAP-based water-immiscible, injectable, sticky, and bioactive 3D coacervate micro-droplets offers a promising tool for chronic diseases in body fluid-rich environments. STATEMENT OF SIGNIFICANCE: High cell retention, long-term survival, and rapid angiogenesis are prerequisites of successful stem cell therapy. However, no previous advancements have simultaneously satisfied all of these requirements. In this work, we clearly developed a novel, revolutionary stem cell carrier platform with underwater adhesiveness from a mussel-derived glue protein and water immiscibility from a sandcastle-worm-inspired glue modality via 'complex coacervation'. To the best of our knowledge, no report has emerged employing coacervate as a stem cell therapeutic platform. This fluid-immiscible, injectable, sticky, and bioactive 3-dimensional stem cell micro-droplets demonstrated the excellent stem cell retention and viability under hypoxia environments and enhanced multipotent and angiogenic effects with minimal immune response.

The heavy-ion accelerator RAON has the advantage of having both an in-flight (IF) and an isotope separator on-line (ISOL) system. Two radio frequency quadrupoles (RFQs) will be installed in the RAON: the main linear accelerator (LINAC) RFQ will be used to accelerate the two-charge state 238U for the IF system, while the post-accelerator RFQ will be used to accelerate low-current isotope beams from the ISOL system. In this paper, the post-accelerator RFQ design for the ISOL system is reported. A beam current of 1 pμA was used, and the input beam and the output beam energies were 5 keV/u and 400 keV/u, respectively. Moreover, the design was optimized by reducing the total length and power, adjusting the beam quality. To quantify the influence of thermal expansion on the frequency, we calculated the frequency difference according to deference between the vane’s tip and the body’s diameter.

RAON has been designed as a rare isotope accelerator facility for the Rare Isotope Science Project (RISP). The main accelerator for the in-flight system accelerates uranium and proton beams to 200 MeV/u and 660 MeV, respectively, with a beam power of 400 kW. The front-end system consists of two 28 GHz electron cyclotron resonance ion sources (10 keV/u), a low-energy beam transport (LEBT) line with two 90° bends, a multi-harmonic buncher with three different rf frequencies, a radio-frequency quadrupole (RFQ), and a medium-energy beam transport line (MEBT) with three rebunchers and eight quadrupoles. A driver linac system consisting of Linac-1 and Linac-2 has been designed to optimize the beam and accelerator parameters so as to meet the required design goals. A charge stripper section is located between Linac-1 and Linac-2. To optimize these designs, we performed start-to-end simulations with the beams from the LEBT to Linac-2 using 1 million macroparticles. We present the resulting beam dynamics to evaluate the performance of the accelerator. Our simulation results predict that the transmission rate of the uranium beam is 85.8% from the LEBT to Linac-2. The designed facility is expected to achieve the required beam loss condition of less than 1 W/m. The RAON driver linac lattice design was developed and an overview of the beam dynamics is presented.

Xenograft bone substitutes, such as deproteinized bovine bone mineral (DBBM), have been widely employed as osteoconductive structural materials for bone tissue engineering. However, the loss of xenograft bone substitute particles in defects has been a major limitation, along with a lack of osteoinductive function. Mussel adhesive protein (MAP), a remarkable and powerful adhesive biomaterial in nature, can attach to various substrates, even in wet environments. Its adhesive and water-resistant abilities are considered to be mainly derived from the reduced catechol form, 3,4-dihydroxyphenylalanine (DOPA), of its tyrosine residues. Here, we evaluated the use of DOPA-containing MAP as a functional binder biomaterial to effectively retain DBBM particles at the defect site during in vivo bone regeneration. We observed that DOPA-containing MAP was able to bind DBBM particles easily to make an aggregate, and grafted DBBM particles were not lost in a defect in the rat calvaria during the healing period. Importantly, grafting of a DOPA-containing MAP-bound DBBM aggregate resulted in remarkably accelerated in vivo bone regeneration and even bone remodeling. Interestingly, we found that the DOPA residues in the modified MAP had an osteoinductive ability based on clear observation of the in vivo maturation of new bones with a similar bone density to the normal bone and of the in vitro osteogenic differentiation of osteoblast cells. Collectively, DOPA-containing MAP is a promising functional binder biomaterial for xenograft bone substitute-assisted bone regeneration with enhanced osteoconductivity and acquired osteoinductivity. This mussel glue could also be successfully utilized as a potential biomaterial for general bone tissue engineering.

Successful titanium implantation strongly depends on early fixation through an osseointegration between the titanium fixture and adjacent bone tissue. From a clinical perspective, rapid recruitment of functional biomolecules from the blood and osteogenic cell binding is critical for osseointegration immediately after implant insertion. Thus, surface modifications aiming to improve the interactions between the blood and implant and to enhance the binding of osteogenic cells onto the implant surface can contribute to successful osseointegration. Mussel adhesive proteins (MAPs) derived from marine mussels have been considered as promising bioadhesives that have strong adhesion and coating abilities onto organic and inorganic surfaces, even in wet environments. Here, we investigated the in vitro and in vivo osteostimulating ability of the bioengineered mussel glue MAP-RGD, which is a recombinant MAP fused with an Arg-Gly-Asp (RGD) peptide, an effective cell recognition motif for activating intracellular signaling pathways, using a titanium mesh (Ti-mesh) as a model titanium implant. We found that the in vitro cell behaviors of pre-osteoblast cells, such as attachment, proliferation, spreading, and osteogenic differentiation, increased significantly on the MAP-RGD-coated Ti-mesh surface. In vitro blood responses including blood wetting, blood clotting, and platelet adhesion were also highly enhanced on the MAP-RGD-coated surface. Importantly, implantation of the MAP-RGD-coated Ti-mesh resulted in a remarkable acceleration of in vivo bone regeneration and maturation of a new bone in a rat calvarial defect. Consequently, the bioengineered mussel glue can be successfully utilized as an osteostimulating bone bioadhesive for titanium implant applications with further expansion to general bone tissue engineering.

Silica nanoparticles (SiNPs) have been utilized to construct bioactive nanostructures comprising surface topographic features and bioactivity that enhances the activity of bone cells onto titanium-based implants. However, there have been no previous attempts to create microrough surfaces based on SiNP nanostructures even though microroughness is established as a characteristic that provides beneficial effects in improving the biomechanical interlocking of titanium implants. Herein, a protein-based SiNP coating is proposed as an osteopromotive surface functionalization approach to create microroughness on titanium implant surfaces. A bioengineered recombinant mussel adhesive protein fused with a silica-precipitating R5 peptide (R5-MAP) enables direct control of the microroughness of the surface through the multilayer assembly of SiNP nanostructures under mild conditions. The assembled SiNP nanostructure significantly enhances the in vitro osteogenic cellular behaviors of preosteoblasts in a roughness-dependent manner and promotes the in vivo bone tissue formation on a titanium implant within a calvarial defect site. Thus, the R5-MAP-based SiNP nanostructure assembly could be practically applied to accelerate bone-tissue growth to improve the stability and prolong the lifetime of medical implantable devices.

During implant surgeries, antibacterial agents are needed to prevent bacterial infections, which can cause the formation of biofilms between implanted materials and tissue. Mussel adhesive proteins (MAPs) derived from marine mussels are bioadhesives that show strong adhesion and coating ability on various surfaces even in wet environment. Here, we proposed a novel surface-independent antibacterial coating strategy based on the fusion of MAP to a silver-binding peptide, which can synthesize silver nanoparticles having broad antibacterial activity. This sticky recombinant fusion protein enabled the efficient coating on target surface and the easy generation of silver nanoparticles on the coated-surface under mild condition. The biosynthesized silver nanoparticles showed excellent antibacterial efficacy against both Gram-positive and Gram-negative bacteria and also revealed good cytocompatibility with mammalian cells. In this coating strategy, MAP-silver binding peptide fusion proteins provide hybrid environment incorporating inorganic silver nanoparticle and simultaneously mediate the interaction of silver nanoparticle with surroundings. Moreover, the silver nanoparticles were fully synthesized on various surfaces including metal, plastic, and glass by a simple, surface-independent coating manner, and they were also successfully synthesized on a nanofiber surface fabricated by electrospinning of the fusion protein. Thus, this facile surface-independent silver nanoparticle-generating antibacterial coating has great potential to be used for the prevention of bacterial infection in diverse biomedical fields.

Silk has recently been exploited in various fields due to its superior mechanical properties. However, this material's lack of biological functions and relatively poor biodegradation have hindered its wide use in applications related to cells and tissues. Here, we improved the overall characteristics of silkworm silk fibroin (SF) by introduction of RGD peptide-fused recombinant mussel adhesive protein (MAP-RGD). Simple blending of MAP-RGD provided not only bulk-scale adhesive ability but also microscale adhesiveness to cells and various biomolecules. MAP-RGD-blended SF fibers supported enhanced adhesion, proliferation, and spreading of mammalian cells as well as the efficient attachment of biomolecules, including carbohydrate and protein. In addition, the hydrophilicity, swelling, and biodegradability of the MAP-RGD-blended SF material were improved without notable hampering of the original mechanical properties of SF. Therefore, the adhesive silk fibrous scaffold could be successfully used in diverse biomedical engineering applications.

The injector for the main driver linac of the Rare Isotope Science Project (RISP) in Korea has been designed to supply ions ranging from proton to uranium which will be used to meet requirements of the 400 kW inflight fragmentation (IF) system. The injector includes two superconducting electron cyclotron resonance (ECR) ion sources, a low energy beam transport (LEBT), a radio frequency quadrupole (RFQ), and a medium energy beam transport (MEBT). Major elements were optimized and selected by calculating uranium beam optics which will then be delivered to the low energy superconducting linac.

A whole cell array biosensor for the efficient detection of neurotoxic organophosphate compounds (OPs) was developed through the immobilization of recombinant Escherichia coli cells containing periplasmic-expressing organophosphorus hydrolase (OPH) onto the surface of a 96-well microplate using mussel adhesive protein (MAP) as a microbial cell-immobilizing linker. Both the paraoxon-hydrolyzing activity and fluorescence microscopy analyses demonstrated that the use of MAP in a whole cell biosensor increased the cell-immobilizing efficiency and enhanced the stability of immobilized cells compared to a simple physical adsorption-based whole cell system. Scanning electron microscopic analyses also showed that the E. coli cells were effectively immobilized on the MAP-coated surface without any pretreatment steps. The whole cell array biosensor system, prepared using optimal MAP coating (50 μg/cm 2 ) and cell loading (4 OD 600 ), detected paraoxon levels as low as 5 μM with high reproducibility, and its quantitative detection range was ∼5–320 μM. The MAP-based whole cell array biosensor showed a good long-term stability for 28 day with 80% retained activity and a reusability of up to 20 times. In addition, paraoxon in tap water was also successfully detected without a reduction in sensitivity. Our results indicate that the proposed MAP-based whole cell array system could be used as a potential platform for a stable and reusable whole cell biosensor.

Nanofibrous scaffolds have been assessed as one of many promising tissue engineering scaffolds to be utilized for wound-healing applications. Previously, we reported multi-functionalized electrospun nanofibrous scaffolds blended with mussel adhesive protein (MAP) and polycaprolactone (PCL), which provide durable mechanical strength, cell-friendly environments, and a substantial ability to capture diverse bioactive molecules without any surface modifications. In the present work, we applied the blended nanofibrous mats of MAP and PCL for in vivo skin wound healing. The nanofibrous mats showed accelerated regeneration in a rat skin wound-healing model, which might be attributed to a highly compatible environment for keratinocyte cell growth, an ability to capture inherent growth factors, and an efficient exudate absorption capacity. Thus, this work would suggest that adhesive property of scaffold could be a factor of successful application for wound healing. The MAP-blended nanofibers could also be potentially exploited for diverse tissue regeneration applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 218-225, 2017.

The injector for the main driver linear accelerator of the Rare Isotope Science Project in Korea, has been developed to allow heavy ions up to uranium to be delivered to the inflight fragmentation system. The critical components of the injector are the superconducting electron cyclotron resonance (ECR) ion sources, the radio frequency quadrupole (RFQ), and matching systems for low and medium energy beams. We have built superconducting magnets for the ECR ion source, and a prototype with one segment of the RFQ structure, with the aim of developing a design that can satisfy our specifications, demonstrate stable operation, and prove results to compare the design simulation.

See paper for full list of authors; The Korea Rare Isotope Accelerator, currently referred to as KoRIA, is briefly presented. The KoRIA facility is aimed to enable cutting-edge sciences in a wide range of fields. It consists of a 70 kW isotope separator on-line (ISOL) facility driven by a 70 MeV, 1 mA proton cyclotron and a 400 kW in-flight fragmentation (IFF) facility. The ISOL facility uses a superconducting (SC) linac for post-acceleration of rare isotopes up to about 18 MeV/u, while the SC linac of IFF facility is capable of accelerating uranium beams up to 200 MeV/u, 8 pμA and proton beams up to 600 MeV, 660 μA. Overall features of the KoRIA facility are presented with a focus on the accelerator design.

The use of mussel adhesive proteins (MAPs) as a surface coating for cell adhesion has been suggested due to their unique properties of biocompatibility and effective adhesion on diverse inorganic and organic surfaces. The surface functionalization of scaffolds or implants using extracellular matrix (ECM) molecules is important for the enhancement of target cell behaviors such as proliferation and differentiation. In the present work, we suggest a new, simple surface functionalization platform based on the charge interactions between the positively charged MAP linker and negatively charged ECM molecules, such as glycosaminoglycans (GAGs). MAP was efficiently coated onto a titanium model surface using its adhesion ability. Then, several GAG molecules, including hyaluronic acid (HA), heparin sulfate (HS), chondroitin sulfate (CS), and dermatan sulfate (DS), were effectively immobilized on the MAP-coated surfaces by charge interactions. Using HA as a model GAG molecule, we found that the proliferation, spreading, and differentiation behaviors of mouse preosteoblast cells were all significantly improved on MAP/HA-layered titanium. In addition, we successfully constructed a multilayer film on a titanium surface with oppositely charged layer-by-layer coatings of MAP and HA. Collectively, our simple MAP-based surface functionalization strategy can be successfully used for the efficient surface immobilization of negatively charged ECM molecules in various tissue engineering and medical implantation applications.

As biodegradable scaffolds, protein hydrogels have considerable potential, particularly for bioartificial organs and three-dimensional space-filling materials. However, their low strength and stiffness have been considered to be limitations for enduring physiological stimuli. Therefore, protein hydrogels have been commonly utilized as delivery vehicles rather than as supporting materials. In this work, sea anemone tentacle-derived recombinant silk-like protein (aneroin) was evaluated as a potential material for a mechanically durable protein hydrogel. Inspired by the natural hardening mechanism, photoinitiated dityrosine cross-linking was employed to fabricate an aneroin hydrogel. It was determined that the fabricated aneroin hydrogel was approximately 10-fold stiffer than mammalian cardiac or skeletal muscle. The aneroin hydrogel provided not only structural support but also an adequate environment for cells. It exhibited an adequate swelling ability and microstructure, which are beneficial for facilitating mass transport and cell proliferation. Based on its mechanical and biological properties, this aneroin hydrogel could be used in various biomedical applications, such as cell-containing patches, biomolecule carriers, and artificial extracellular matrices.

Currently approved surgical tissue glues do not satisfy the requirements for ideal bioadhesives due to limited adhesion in wet conditions and severe cytotoxicity. Herein, we report a new light-activated, mussel protein-based bioadhesive (LAMBA) inspired by mussel adhesion and insect dityrosine crosslinking chemistry. LAMBA exhibited substantially stronger bulk wet tissue adhesion than commercially available fibrin glue and good biocompatibility in both in vitro and in vivo studies. Besides, the easily tunable, light-activated crosslinking enabled an effective on-demand wound closure and facilitated wound healing. Based on these outstanding properties, LAMBA holds great potential as an ideal surgical tissue glue for diverse medical applications, including sutureless wound closures of skin and internal organs.

Marine mussels use MAPs (MAPs) for their adhesion. MAPs have fascinating properties, including strong adhesion to various material substrates, water displacement, biocompatibility, and controlled biodegradability. In this work, among six types of MAPs, including fp-1–fp-6, biosynthetic constructs of MAPs are considered; hybrid type recombinant MAPs are designed to improve productivity and purification. Hybrid recombinant fp-151, which comprises six decapeptide repeats of fp-1 at both N and C-termini of fp-5, was successfully overexpressed in a bacterial system, showing approximately ≈ 1 g / L Open image in new window production yield in a pilot scale fed-batch bioreactor culture. For industrial applications, it was attempted to use MAPs in tissue engineering fields as coating extracellular matrix (ECM ) through surface modification and constructing nanofibrous scaffolds. As a result, the MAP-based coating strategy could be generally applied for facile and efficient surface modification of negatively charged bioactive molecules for tissue engineering. The use of MAP-based nanofibers could provide bioactive peptides efficiently onto the scaffold surface, enhancing the cell attachment and proliferation on the nanofibers fabricated using RGD peptide-conjugated MAPs compared with bare polycaprolactone (PCL ) polymer nanofibers as well having a four times higher mechanical strength. Also, easy fabrication through blending with diverse types of synthetic polymers and significant bone regeneration was observed. In addition, there was a trial for utilization of MAPs in pharmaceutics, cosmetics, and food industries with encapsulating active molecules such as chemical drugs, proteins, cells, and flavor ingredients through a complex coacervation technique based on MAPs.

The purpose of this study was to examine the isomer-specific effect of conjugated linoleic acid (CLA) on inflammatory markers associated with fat accumulation in cultures of differentiating 3T3-L1 adipocytes. trans-10,cis-12 CLA (t10c12 CLA) reduced leptin secretion and fat accumulation. Linoleic acid (LA) and cis-9,trans-11 CLA (c9t11 CLA) increased them, but not significantly. t10c12 CLA and LA showed similar effects on mRNA expression of inflammatory markers. t10c12 CLA and LA tended to up-regulate the mRNA levels of inflammatory cytokines such as interleukin (IL)-6 (not significantly), tumor necrosis factor (TNF)-alpha, and C-reactive protein (CRP) with no significant change in the secretion of adiponectin, an anti-inflammatory adipokine. However, c9t11 CLA induced no significant change in the mRNA expression of IL-6, TNF-alpha, or CRP, but significantly increased adiponectin secretion. In conclusion, CLA exerted isomer-specific effects on fat accumulation and mRNA expression of inflammatory markers in 3T3-L1 adipocytes. t10c12 CLA up-regulated inflammatory markers in spite of the decreased fat accumulation, and TNF-alpha might be one of the causal factors.

In order to improve the antiobesity effect of Kochujang, 1% of sea tangle powder, alginic acid extract, and fucoidan extract were added to Kochujang. Sea tangle powder-added Kochujang decreased leptin secretion by only 12% compared to Kochujang, whereas alginic acid or fucoidan-added Kochujang significantly decreased leptin secretion by more than 60% in 3T3-L1 adipocytes. Fucoidan, one of the active components of sea tangle, decreased leptin secretion by 56%, 60%, and 60% compared to the control in the concentrations of 1 μM, 2.5 μM, and 5 μM, respectively. To see the effect of fucoidan on TG formation during adipocyte differentiation, 3T3-L1 cells were treated with 1 μM and 5 μM concentrations of fucoidan during adipocyte differentiation (from “day 0” to “day 6”). Oil red O staining showed fucoidan decreased the amount of TG droplets and 5 μM fucoidan potently inhibited TG formation. To see the effect of fucoidan on lipolysis, differentiated 3T3-L1 adipocytes were treated with fucoidan. The secretion of glycerol, which is used to measure lipolytic activity, was increased by 21%, 37%, and 53% compared to the control in the concentrations of 1 μM, 2.5 μM, and 5 μM, respectively. Oil red O staining showed fucoidan decreased TG amount at 1 μM and 5 μM concentrations. These results suggest that fucoidan decreases leptin secretion and TG accumulation by inhibition of adipocyte differentiation and induction of lipolysis. Since fucoidan is reported to have various biological activities in addition to an anti-adipogenic effect, it seems valuable to develop fucoidan-added Kochujang as a multi-functional Kochujang.

The Rare isotope Accelerator Of Newness (RAON) heavy-ion accelerator has been designed for the Rare Isotope Science Project (RISP) in Korea. The RAON will produce heavy-ion beams from 660-MeV-proton to 200-MeV/u-uranium with continuous wave (CW) power of 400 kW to support research in various scientific fields. Its system consists of an ECR ion source, LEBTs with 10 keV/u, CW RFQ accelerator with 81.25 MHz and 500 keV/u, a MEBT system, and a SC linac. In detail, the driver linac system consists of a Quarter Wave Resonator (QWR) section with 81.25 MHz and a Half Wave Resonator (HWR) section with 162.5 MHz, Linac-1, and a Spoke Cavity section with 325 MHz, Linac-2. These linacs have been designed to optimize the beam parameters to meet the required design goals. At the same time, a light-heavy ion accelerator with high-intensity beam, such as proton, deuteron, and helium beams, is required for experiments. In this paper, we present the design study of the high intensity RFQ for a deuteron beam with energies from 30 keV/u to 1.5 MeV/u and currents in the mA range. This system is composed of an Penning Ionization Gauge ion source, short LEBT with a RF deflector, and shared SC Linac. In order to increase acceleration efficiency in a short length with low cost, the 2nd harmonic of 162.5 MHz is applied as the operation frequency in the D+ RFQ design. The D+ RFQ is designed with 4.97 m, 1.52 bravery factor. Since it operates with 2nd harmonic frequency, the beam should be 50% of the duty factor while the cavity should be operated in CW mode, to protect the downstream linac system. We focus on avoiding emittance growth by the space-charge effect and optimizing the RFQ to achieve a high transmission and low emittance growth. Both the RFQ beam dynamics study and RFQ cavity design study for two and three dimensions will be discussed.

Adhesion of cells to a surface is a basic and important requirement in the fields of cell culture and tissue engineering. Previously, we constructed the cell adhesive, fp-151-RGD, by fusion of the hybrid mussel adhesive protein, fp-151, and GRGDSP peptide, one of the major cell adhesion recognition motifs; fp-151-RGD efficiently immobilized cells on coated culture surfaces with no protein and surface modifications, and apparently enhanced cell adhesion, proliferation, and spreading abilities. In the present study, we investigated the potential use of fp-151-RGD as a biomimetic extracellular matrix material at the molecular level by elucidating its substantial effects on integrin-mediated adhesion and signaling. Apoptosis derived from serum deprivation was significantly suppressed on the fp-151-RGD-coated surface, indicating that RGD-induced activation of integrin-mediated signaling triggers the pathway for cell survival. Analysis of the phosphorylation of focal adhesion kinase clearly demonstrated activation of focal adhesion kinase, a well-established indicator of integrin-mediated signaling, on the fp-151-RGD-coated surface, leading to significantly enhanced cell behaviors, including proliferation, spreading and survival, and consequently, more efficient cell culture.

The Korea Multipurpose Accelerator Complex (KOMAC) project has been initiated to develop and build a high current proton/H− linear accelerator capable of delivering an 1 GeV cw proton beam with an intensity of 20 mA in the final stage. The major proton beam will be used for nuclear-waste transmutation, energy production, and nuclear physics experiments while utilizing the minor negative hydrogen beam for basic science research and medical therapy. A Duoplasmatron proton source for the KOMAC linear accelerator has been built at Korea Atomic Energy Research Institute. The hydrogen beam currents of up to 50 mA at the extraction voltage of 50 kV are routinely obtained. A low normalized rms emittance of 0.2 π mm mrad and a proton fraction of over 80% are obtained in this source. With the 100% duty factor of ion source operation, the arc filaments of the source have survived over 40 h. Except for the filament lifetime, the achieved parameters of the proton beam source are satisfying most requirements of the KOM...

Berberine (BBR), an isoquinoline alkaloid, has a wide range of pharmacological effects, yet its exact mechanism is unknown. In order to understand the anti-adipogenic effect of BBR, we studied the change of expression of several adipogenic enzymes of 3T3-L1 cells by BBR treatment. First, we measured the change of leptin and glycerol in the medium of 3T3-L1 cells treated with 1 micrometer, 5 micrometer and 10 micrometer concentrations of BBR. We also measured the changes of adipogenic and lipolytic factors of 3T3-L1. In 3T3-L1 cells, both leptin and adipogenic factors (SREBP-1c, C/EBP-alpha, PPAR-gamma, fatty acid synthase, acetyl-CoA carboxylase, acyl-CoA synthase and lipoprotein lipase) were reduced by BBR treatment. Glycerol secretion was increased, whereas expression of lipolytic enzymes (hormone-sensitive lipase and perilipin) mRNA was slightly decreased. Next, we measured the change of inflammation markers of 3T3-L1 cells by BBR treatment. This resulted in the down-regulation of mRNA level of inflammation markers such as TNF-alpha, IL-6, C- reactive protein and haptoglobin. Taken together, our data shows that BBR has both anti-adipogenic and anti-inflammatory effects on 3T3-L1 adipocytes, and the anti-adipogenic effect seems to be due to the down-regulation of adipogenic enzymes and transcription factors.

Background: Unique adhesive and biocompatibility properties of mussel adhesive proteins (MAPs) are known for their great potential in many tissue engineering and biomedical applications. Previously, it was successfully demonstrated that redesigned hybrid type MAP, fp-151, mass-produced in Gram-negative bacterium Escherichia coli, could be utilized as a promising adhesive biomaterial. However, purification of recombinant fp-151 has been unsatisfactory due to its adhesive nature and polarity which make separation of contaminants (especially, lipopolysaccharide, a toxic Gram-negative cell membrane component) very difficult. Results: In the present work, we devised a high resolution purification approach to secure safety standards of recombinant fp-151 for the successful use in in vivo applications. Undesirable impurities were remarkably eliminated as going through sequential steps including treatment with multivalent ion and chelating agent for cell membrane washing, mechanical cell disruption, non-ionic surfactant treatment for isolated inclusion body washing, acid extraction of washed inclusion body, and ion exchange chromatography purification of acid extracted sample. Through various analyses, such as high performance liquid chromatographic purity assay, limulus amoebocyte lysate endotoxin assay, and in vitro mouse macrophage cell tests on inflammation, viability, cytotoxicity, and apoptosis, we confirmed the biological safety of bacterial-derived purified recombinant fp-151. Conclusions: Through this purification design, recombinant fp-151 achieved 99.90% protein purity and 99.91% endotoxin reduction that nearly no inflammation response was observed in in vitro experiments. Thus, the highly purified recombinant MAP would be successfully used as a safety-secured in vivo bioadhesive for tissue engineering and biomedical applications.

Mussel adhesive protein (MAP) fp-151 designed and constructed by our research laboratory has the potential to be used as a cell or tissue bioadhesive at various cell lines in biocompatible aspect. To improve the cell-adhesion and proliferation properties of fp151, we designed an extracellular matrix (ECM) mimics based on mussel adhesive protein fused with biofunctional peptides such as RGD, laminin, type Ⅳ collagen, growth factor called substance P, which is fused at Cterminus of fp151. The ability of adhesion and proliferation properties is tested in several cell lines by direct cell count (DCC) method and MTT assay. Our ECM mimics showed better or similar adhesion and proliferation properties compared with other commercially produced cell-adhesion materials such as poly-L-lysine (PLL) and the naturally extracted MAP mixture Cell-Tak in MC3T3-E1, ATDC5 and 3T3-L1 cells. These data showed that these mimics can be successfully used in cell culture and tissue engineering and extended to other tissuespecific cell recognition motifs to allow attachment of target cells to artificial ECM surfaces.

In our previous study, we have shown that berberine has both anti-adipogenic and anti-inflammatory effects on 3T3-L1 adipocytes, and the anti-adipogenic effect is due to the down-regulation of adipogenic enzymes and transcription factors. Here we focused more on anti-inflammatory effect of berberine using real time RT-PCR and found it changes expressions of adipokines. We hypothesized that anti-adipogenicity of berberine mediates anti-inflammtory effect and explored leptin as a candidate mediator of this signaling. We studied this hypothesis by western blot analysis, but our results showed that berberine has no effect on the phosphorylations of STAT-3 and ERK which have important roles on leptin signaling. These results led us to conclude that the anti-inflammatory effect of berberine is not mediated by the inhibition of leptin signal transduction. Moreover, we have found that berberine down-regulates NF-kappaB signaling, one of the inflammation-related signaling pathway, through western blot analysis. Taken together, the anti-inflammatory effect of berberine is not mediated by leptin, and berberine induces anti-inflammatory effect independent of leptin signaling.

B cell activation factor (BAFF) is a novel member of the TNF ligand superfamily, mainly produced by myeloid cells. BAFF has been shown to participate in B-cell survival and B- and T-cell maturation. BAFF expression in adipocytes has been recently demonstrated. In the current study, we verified that BAFF expression is increased during adipocyte differentiation. BAFF expression was augmented by TNF-alpha treatment and was decreased by rosiglitazone treatment. BAFF secretion in lean and in ob/ob mice sera were compared and smaller amount of BAFF was secreted in ob/ob mice. mRNA and protein expression were different between epididymal and visceral adipose tissue. BAFF expression was also increased in ob/ob mouse adipose tissue. We sought to identify known BAFF receptors (BAFF-R, BCMA, and TACI) in adipocytes, and determined that all three were present and upregulated during adipocyte differentiation. However, the expression of TACI was distinct from that of BAFF-R and BCMA under TNF-alpha and BAFF ligand treatment. BAFF-R and BCMA expression levels were upregulated under pro-inflammatory conditions, but TACI was reduced. Conversely, BAFF-R and BCMA expression levels were downregulated by rosiglitazone treatment, but TACI was increased. Taken together, our results suggest that BAFF may be a new adipokine, representing a link between obesity and inflammation.

We report here the use of human inflammation arrays to study the inflammatory gene expression profile of TNF-alpha- treated human SGBS adipocytes. Human preadipocytes (SGBS) were induced to differentiate in primary culture, and adipocyte differentiation was confirmed, using Oil Red O staining. We treated the differentiated adipocytes with TNF-alpha, and RNA from differentiated adipocytes with or without TNF-alpha treatment was hybridized to MWG human inflammation arrays to compare expression profiles. Eleven genes were up- or down-regulated in TNF-alpha-treated adipocytes. As revealed by array analysis, among 6 up-regulated genes, only eotaxin-1, monocyte chemoattractant protein-1 (MCP-1), and vascular cell adhesion molecule 1 isoform a precursor (VCAM1) were confirmed by real-time polymerase chain reaction (PCR). Similarly, among 5 down-regulated genes, only IL-1 family member 5 (IL1F5), a disintegrin and metalloprotease with thrombospondin motifs-1 preproprotein (ADAMTS1), fibronectin 1 isoform 1 preprotein (FN1), and matrix metalloproteinase 15 preprotein (MMP15) were confirmed by real-time PCR. There was a substantial increase (50-fold) in eotaxin-1 in response to TNF-alpha. Taken together, we have identified several inflammatory molecules expressed in SGBS adipocytes and discovered molecular factors explaining the relationship between obesity and atherosclerosis, focusing on inflammatory cytokines expressed in the TNF-alpha-treated SGBS cells. Further investigation into the role of these up- or down-regulated cytokine genes during the pathological processes leading to the development of atherosclerosis is warranted.

Adipose tissues were initially introduced as energy storages, but recently they have become famous as an endocrine organ which produces and secretes various kinds of molecules to make physiologic and metabolic changes in human body. It has been studied that these molecules are secreted in abundance as the adipose tissue becomes bigger along with obesity. Furthermore, it has been found that they are mediating systemic inflammation and generation of metabolic diseases such as type 2 diabetes and atherosclerosis. On the basis of these, we studied previous papers which have been researched about the interaction between preadipocytes and macrophages, adipose tissues and lymph nodes, and adipose tissue secreting molecules. Results: Firstly, preadipocytes and macrophages are expressing similar transcriptomes and proteins, and preadipocytes can be converted to mature macrophages which have phagocytic activity. Moreover, the monocytes, which initially located in the bone marrow, are filtrated to the adipose tissue by monocyte chemotatic protein-1 and are matured to macrophages by colony stimulating factor-1. Secondly, adipose tissues and their associated lymph nodes are interacting each other in terms of energy efficiency. Lymph nodes promote lipolysis in adipose tissues, and polyunsaturated fatty acids in adipocytes become energy sources for dendritic cells. Lastly, adipose tissues produce and secrete proinflammatory molecules such as leptin, adiponectin, TNF-α, IL-6, and acute phase proteins, which induce the inflammation and potentially generate metabolic diseases. Conclusion: According to these, we can link adipose tissues to inflammation, but we need to affirm the actual levels and roles of adipose tissue-derived proinflammatory molecules in human body.