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Controlling the morphology and surface properties of gold nanocrystals (AuNCs) can facilitate tailoring their localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS) properties for biomedical applications. However, the shape-controlled synthesis of AuNCs for bioapplications remains challenging, given its critical issues, such as the use of toxic reagents and multiple complicated steps. This study demonstrates the facile, biocompatible, and shape-controllable synthesis of AuNCs. This method employs human α-elastin (HαE) self-assemblies as a shape-directing template, reducing agent, and surfactant. Since HαE is a ubiquitous protein present in human tissue, it is non-toxic and non-immunogenic. This method is thus simple and biocompatible. Of particular note, the sheet-type HαE template enables the shape-controlled synthesis of AuNCs—gold nanoparticles, nanosheets, and a rose-flower-like nanostructure (AuRF) stacked with multiple nanosheets. Among the AuNCs, the AuRF exhibits unique optical and electromagnetic properties—an LSPR peak in the near-infrared (NIR) region and characteristic SERS peaks—given the rough surface with sharp edges. To the best of our knowledge, this is the first report on the biosynthesis of AuNCs using human-derived biomolecules such as HαE. The shape-controllable biosynthesis of AuNCs based on HαE may open up possibilities for a wide range of biomedical applications of AuNCs.

A new species of Lecithocera Herrich-Shaffer, L. atriptera Park, sp. nov., is described from Korea, and two species, Homaloxestis myeloxesta Meyrick, 1932 and Lecitholaxa indigens (Meyrick, 1914), are reported for the first time from Korea. Halolaguna sublaxata Gozmany is newly known from Isl. Jeju-do. In addition, new localities for the six previously known species are given. A tentative checklist of Lecithoceridae in Korea is provided, with their type depositories.

A new species of Zanclognatha Lederer, 1857 of the family Erebidae, Z. querciella sp.n., one species of Family Erebidea, Asota egens (Walker, 1854) and two species of Family Noctuidae: Meganephria retinea Gyulai and Ronkay, 1999 and Amphipyra subrigua Bremer and Grey, 1853, are reported for the first time from Korea. In addition, larval feeding habits with their host plants for three species are newly recognized from Korea. Illustration of adults, larvae for Zanclognatha querciella and Meganephria retinea, and the genitalia of male or female for all species are provided.

Three genera Megacraspedus Zeller, 1839, Aulidiotis Meyrick, 1925, and Cuprina Sinev, 1988 and four species of the superfamily Gelechioidea are reported for the first time from the Korean Peninsula. They are Megacraspedus coleophorodes (Li and Zheng, 1995) and Aulidiotis phoxopterella (Snellen, 1903) of Gelechiidae; Martyringa ussuriella Lvovsky, 1979 of Oecophoridae; and Cuprina fuscella Sinev, 1988 of Stathmopodidae. Images of adults and genitalia of the species are given. Keywords: Lepidoptera, Aulidiotis, Cuprina, Megacraspedus, New record

Human adipose-derived stem cells (hADSCs) formed robust cell sheets by engineering the cells with soluble cell adhesive molecules (CAMs), which enabled unique approaches to harvest large area hADSC sheets. As a soluble CAM, fibronectin (FN) (100 pg/ml) enhanced the cell proliferation rate and control both cell-to-cell and cell-to-substrate interactions. Through this engineering of FN, a transferrable hADSC sheet was obtained as a free-stranding sheet (122.6 mm2) by a photothermal method. During the harvesting of hADSC sheets by the photothermal method, a collagen layer in-between cells and conductive polymer film (CP) was dissociated, to protect cells from direct exposure to a near infrared (NIR) source. The hADSC sheets were applied to chronic wound of genetically diabetic db/db mice in vivo, to accelerate 30% faster wound closure with a high closure effect (εwc) than that of control groups. These results indicated that the engineering of CAM and collagens allow hADSC sheet harvesting, which could be extended to engineer various stem cell sheets for efficient therapies.

Self-assembled nanoparticles based on PEGylated human α-elastin were prepared as a potential vehicle for sustained protein delivery. The α-elastin was extracted from human adipose tissue and modified with methoxypolyethyleneglycol (mPEG) to control particle size and enhance the colloidal stability. The PEGylated human α-elastin showed sol-to-particle transition with a lower critical solution temperature (LCST) of 25°C-40°C in aqueous media. The PEGylated human α-elastin nanoparticles (PhENPs) showed a narrow size distribution with an average diameter of 330±33nm and were able to encapsulate significant amounts of insulin and bovine serum albumin (BSA) upon simple mixing at low temperature in water and subsequent heating to physiological temperature. The release profiles of insulin and BSA showed sustained release for 72h. Overall, the thermo-responsive self-assembled PhENPs provide a useful tool for a range of protein delivery and tissue engineering applications.

Stem cell therapy requires large numbers of stem cells to replace damaged tissues, but only limited numbers of stem cells can be harvested from a single patient. To obtain large quantities of stem cells with differentiation potential, we explored a spinner culture system using human extracellular matrix (hECM) powders. The hECM was extracted from adipose tissue and fabricated into powders. Human adipose-derived stem cells (hASCs) were isolated, seeded on hECM powders, and cultivated in a spinner flask. The 3-D culture system, using hECM powders, was highly effective for promoting cell proliferation. The number of hASCs in the 3-D culture system significantly increased for 10 days, resulting in an approximately 10-fold expansion, whereas a traditional 2-D culture system showed just a 2.8-fold expansion. Surface markers, transcriptional factors, and differentiation potential of hASCs were assayed to identify the characteristics of proliferated cells in 3-D culture system. The hASCs expressed the pluripotency markers, Oct-4 and Sox-2 during 3-D culture and retained their capacity to differentiate into adipogenic, osteogenic, and chondrogenic lineages. These findings demonstrate that the 3-D culture systems using hECM powders provide an efficient in vitro environment for stem cell proliferation, and could act as stem cell delivery carriers for autologous tissue engineering and cell therapy.

Decellularized tissues composed of extracellular matrix (ECM) have been clinically used to support the regeneration of various human tissues and organs. Most decellularized tissues so far have been derived from animals or cadavers. Therefore, despite the many advantages of decellularized tissue, there are concerns about the potential for immunogenicity and the possible presence of infectious agents. Herein, we present a biomaterial composed of ECM derived from human adipose tissue, the most prevalent, expendable, and safely harvested tissue in the human body. The ECM was extracted by successive physical, chemical, and enzymatic treatments of human adipose tissue isolated by liposuction. Cellular components including nucleic acids were effectively removed without significant disruption of the morphology or structure of the ECM. Major ECM components were quantified, including acid/pepsin-soluble collagen, sulfated glycosaminoglycan (GAG), and soluble elastin. In an in vivo experiment using mice, the decellularized ECM graft exhibited good compatibility to surrounding tissues. Overall results suggest that the decellularized ECM containing biological and chemical cues of native human ECM could be an ideal scaffold material not only for autologous but also for allograft tissue engineering.

Objective. Zinc inhibits the growth of several carcinoma cells through induction of cell cycle arrest and apoptosis. The intracellular concentration of zinc and its dynamic changes are critically important in cell biology. We investigated the effects of zinc–citrate compound (CIZAR®) on normal human ovarian epithelial cells (NOSE) and human epithelial ovarian cancer cell line, OVCAR-3. Methods. To investigate the potential effect of CIZAR® on cell growth and survival, cells were treated with different doses and exposed to different times. Intracellular concentration of zinc was measured by colorimetric assay. Mitochondrial aconitase activity was determined in cell extracts using aconitase assay. The flow cytometric assay, DNA laddering, and morphological analysis were done to investigate cytotoxic effects of CIZAR®. Molecular mechanism of cell death was investigated by p53, Bcl-xL, Bcl-2, Bax protein, activity of caspase-3 and -12, and activity of telomerase. Results. CIZAR®-induced zinc accumulation in OVCAR-3 cells was higher than that in NOSE cells. CIZAR® treatment resulted in a time- and dose-dependent decrease in cell number in OVCAR-3 cells in comparison with NOSE cells. M-aconitase activity was significantly decreased in OVCAR-3 cells within 4 h exposure to CIZAR® but relatively constant in NOSE cells. The flow cytometric assay, DNA laddering, and morphological analysis indicated apoptosis in OVCAR-3 cells but not in NOSE cells. CIZAR® increased the expression of p21 waf1 which is a part of p53-independent pathway and induced reduction of telomerase activity. CIZAR® reduced expression of Bcl-2 and Bcl-xL proteins but induced expression of Bax protein. CIZAR® induced apoptosis of OVCAR-3 cells by activation of caspase-12 and caspase-3 pathway. Conclusions. Exposure to CIZAR® induces apoptosis in OVCAR-3 cells which accumulate high intracellular levels of zinc, but not in NOSE cells, which do not accumulate high levels of zinc. CIZAR® prevents the proliferation of OVCAR-3 cells by inactivation of m-aconitase activity and induces apoptosis by induction of proapoptotic gene (Bax), repression of antiapoptotic genes (Bcl-2, Bcl-xL), and consequently activation of caspase-3. CIZAR® also induced activation of caspase-12. The CIZAR® will offer new window in prevention and treatment of epithelial ovarian cancer.

Objective . From the knowledge of risk factors of epithelial ovarian cancer, we deduced a hypothesis that human seminal plasma (HSP) has a preventive role in the development of epithelial ovarian cancer. To examine whether HSP directly influences the growth of ovarian cancer, we have investigated the in vitro and in vivo effect of HSP on ovarian adenocarcinoma cell lines (SK-OV-3 and OVCAR-3) in comparison with its effects on normal ovarian surface epithelial cells (NOSE). Methods . Cell viability was determined by MTT assay. Cytotoxic effect was evaluated by flow cytometry analysis, by DNA laddering, and by morphological analysis. In vivo therapeutic effect of HSP was evaluated by the subcutaneous inoculation of SK-OV-3 cells in nude mice (BALB-c) model. Results . HSP at a final concentration of 1:50 induced a time- and dose-dependent inhibition of SK-OV-3 and OVCAR-3 growth, whereas NOSE was not affected. Flow cytometric analysis, DNA laddering, and morphological analysis indicated that HSP induced necrosis, rather than apoptosis, of both ovarian carcinoma cell lines. In in vivo experiment that used the nude mice (Balb-C) with tumor inoculation of SK-OV-3 cells, HSP induced necrosis of tumor with no detectable toxic effects on the major organs. Conclusion . These results show that HSP inhibits the growth and induces the necrosis of epithelial ovarian cancer cells and suggests that one or more components of HSP may provide a scientific basis for preventing epithelial ovarian cancer.

By measuring the activity of telomerase in a silica-instilled rat lung, the study found a significant increase in telomerase activity compared to that of the control. Pneumoconiosis displays the characteristics of fibroblast-proliferation and accumulation of collagen, which finally causes the pathologic changes of irreversible and progressive fibrosis of the lung. On the basis of the hypothesis that cellular proliferation may trigger telomerase-activity, the experiment was carried out with telomerase-activation in silicosis. Silica-instilled rat lungs showed increased activity of telomerase, which was measured by TRAP (telomeric repeat amplification protocol) assay, at the time of the 1st, 5th and 8th week after intratracheal instillation of silica in vivo. However, no activity was shown in silica-co-cultured fibroblast in vitro. By summarizing these results, the activity of telomerase is thought to be a very sensitive marker for the evaluation of pathogenicity, showing cellular immortalization in an experimental silicosis model.

Cells in tissues are surrounded by the extracellular matrix (ECM), a gel-like material of proteins and polysaccharides that are synthesized and secreted by cells. Here we propose that the ECM can be isolated from porcine adipose tissue and holds great promise as a xenogeneic biomaterial for tissue engineering and regenerative medicine. Porcine adipose tissue is easily obtained in large quantities from commonly discarded food waste. Decellularization protocols have been developed for extracting an intact ECM while effectively eliminating xenogeneic epitopes and minimally disrupting the ECM composition. Porcine adipose tissue was defatted by homogenization and centrifugation. It was then decellularized via chemical (1.5 M sodium chloride and 0.5% sodium dodecyl sulfate) and enzymatic treatments (DNase and RNase) with temperature control. After decellularization, immunogenic components such as nucleic acids and α-Gal were significantly reduced. However, abundant ECM components, such as collagen (332.9±12.1 μg/mg ECM dry weight), sulfated glycosaminoglycan (GAG, 85±0.7 μg/mg ECM dry weight), and elastin (152.6±4.5 μg/mg ECM dry weight), were well preserved in the decellularized material. The biochemical and mechanical features of a decellularized ECM supported the adhesion and growth of human cells in vitro. Moreover, the decellularized ECM exhibited biocompatibility, long-term stability, and bioinductivity in vivo. The overall results suggest that the decellularized ECM derived from porcine adipose tissue could be useful as an alternative biomaterial for xenograft tissue engineering.

Mass mortality occurred among Penaeus vannamei shrimp cultured in Korea in 2004. In an earlier study, we reported white spot syndrome virus (WSSV) as a causative agent of mass mor- tality of P. monodon shrimp in Korea (Moon et al. 2003; Dis Aquat Org 53:11-13). However, in the present study, we detected Taura syndrome virus (TSV) from the moribund 2004 P. vannamei shrimp by reverse transcription polymerase chain reaction (RT-PCR). In addition, during our regular screen- ing for the TSV in stocks of P. vannamei imported from Hawaii, USA, we also detected TSV by RT- PCR. The nucleotide sequences of the partial capsid protein VP1 of 2 Korean isolates were 99% iden- tical to each other and 96 to 99% identical to those of TSVs isolated from the Americas, Taiwan, and Thailand. Phylogenetic analysis revealed that the 2 Korean isolates were closely related to TSV types from Thailand. This is the first report on the detection of TSV during an epizootic among cultured P. vannamei in Korea, and our results suggests the possibility that TSV has been introduced via the imported stock of P. vannamei.

Y.-H. KANG, J.-D. KIM, B.-H. KIM, D.-S. KONG AND M.-S. HAN. 2005. Aims: Identification of bacterium HYK0203-SK02 and its lysis of Stephanodiscus hantzschii. Methods and Results: In an effort to identify a bio-agent capable of controlling S. hantzschii blooms, we used the algal lawn method to identify 76 bacteria in relevant water samples. Of these, the seven isolate showed algicidal activity against S. hantzschii; isolate HYK0203-SK02 exhibited the strongest algicidal activity, and was used for further analysis. 16S rDNA sequencing of this isolate allowed us to identify HYK0203-SK02 as a strain of Pseudomonas putida (99AE2%). Growth of S. hantzschii was strongly suppressed by bacteria in all growth phases, with the strongest algicidal activity noted against diatoms in the exponential stage (5‐18 days). Host range assays revealed that isolate HYK0203-SK02 also strongly inhibited the growth of Microcystis aeruginosa, but stimulated growth of the diatom Cyclotella sp., which has a similar structure to that of S. hantzschii. Biochemical assays revealed that the algicidal substance seemed to be localized in the cytoplasmic membrane of this newly identified algicidal bacterium. Conclusion: The algicidal bacteria P. putida HYK0203-SK02 caused cell lysis and death of not only diatom S. hantzschii but also cyanobacteria M. aeruginosa, dramatically. Algicidal substance might be located at the compartment of cytoplasmic membrane. Significance and Impact of the Study: Taken together, our results indicate that P. putida HYK0203-SK02 may be a potential bio-agent for future use in controlling freshwater diatomic blooms.