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This study was conducted to examine the effects of microwave cold plasma (CP) treatment on inactivation of polyphenol oxidase (PPO) of potato. The PPO activity and treatment variables were fit to first-order kinetics, the Weibull model, and the second-order model. The optimum CP-generation power and treatment time for inactivating PPO in the PPO extract were found to be 900 W and 40 min, respectively, which resulted in the highest inactivation of PPO (49.5%). PPO activity after CP treatment of potato slices decreased from 72.4% to 59.0% as the sample surface-to-volume ratio increased from 7.1 to 9.0. CP treatment delayed the browning of potato slices. Microwave CP treatment effectively inactivated PPO in potatoes, demonstrating the potential of CP treatment for controlling PPO activity in foods. PRACTICAL APPLICATION: This study demonstrated that microwave CP treatment, a nonthermal food processing technology, inactivates PPO activity in potatoes. The results showed that the inactivation effect of CP treatment on PPO corresponded to the surface-to-volume ratio of potato slices. Furthermore, this study proposed an enzyme inactivation model that is suitable for predicting the inactivation of PPO activity and confirmed that CP treatment delayed browning in potatoes.

The purpose of this study is to evaluate the efficacy of bone regeneration and volume maintenance of the three-dimensional (3D) structured biphasic calcium phosphate (BCP) block with porous hexahedron channels in a rabbit calvarial model. In this work, four circular defects (diameter: 8 mm) in calvarium of rabbits were randomly assigned to (1) negative control (control), (2) 3D hexahedron channel structured BCP block, (3) deproteinized bovine bone mineral particle, and (4) deproteinized porcine bone mineral particle. Animals were euthanized at 2 (n = 5) and 8 weeks (n = 5). Outcome measures included micro-computed tomography (CT) and histomorphometrical analysis. Results indicated that in micro-CT, BCP group showed the highest new bone volume with significant difference compared to control (p = 0.008) at 8 weeks. Histomorphometrically, total augmented area of BCP group was the highest with significant difference compared to control (p = 0.008) at 8 weeks. BCP group also maintained total volume of the original defect without collapsing. BCP block with 3D hexahedron channel structure seems to have favorable osteogenic and volume maintaining ability and highly porous structure might attribute to new bone formation. Further studies regarding the optimal internal structure and porosity of the BCP block bone substitute are needed. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2254-2262, 2019.

Gulfweed-based edible materials were developed in forms of food film and coating. Gulfweed suspension was subjected to high-pressure homogenization (HPH) at 103, 138, and 193 MPa with 1, 2, and 3 passes, and mixed with 14, 30, 50, and 70% (w/w gulfweed) glycerol and 1% (w/w gulfweed) polysorbate 20 to produce a film-forming suspension. The particle size of the suspension decreased with increasing pressure from 103 to 193 MPa and pass number from 1 to 3. The HPH-treated gulfweed suspension behaved like a pseudo-plastic non-Newtonian fluid. High pressure and pass number generally decreased the suspension viscosity. Uniformity and compactness of the films increased with increasing pressure. The optimal conditions for forming a film with high stretchability, low water vapor permeability, low and water solubility, as well as for preparing bright-colored coated smoked salmon, were found to be 193 MPa, three passes of HPH, and a glycerol concentration of 70%. Coating smoked salmon with gulfweed suspension enhanced the redness without altering its texture and volatile properties. The method reported in this study may be useful for seaweed-based edible film production, increasing their potential application to various food products like red meats. PRACTICAL APPLICATION: Seaweeds have high nutritional and functional values, but they are not commonly used as food materials owing to their appearance and size. Therefore, it is important to develop methods to utilize seaweeds by overcoming appearance and size limitations. A self-standing film/coating using gulfweed was developed in this study, making use of commercially available high-pressure homogenization technology. The method developed herein might enable increased applications of gulfweed and possibly other seaweeds to food products such as films, rolls, or coatings.

Defect-specific bone regeneration using 3-dimensional (3D) printing of block bone has been developed. Polycaprolactone (PCL) is biocompatible polymer that can be used as 3D scaffold. The aim of this study is to assess the biocompatibility and osteogenic efficacy of 3D printed PCL scaffold and to evaluate the effectiveness of β-tricalcium phosphate (β-TCP) addition in PCL scaffold. In this work, four circular defects (diameter: 8 mm) in rabbit calvarium were randomly assigned to (1) negative control (control), (2) PCL block (PCL), (3) PCL mixed with 10 wt% β-TCP (PCL/β-TCP), and (4) PCL/β-TCP plus collagen membrane (PCL/β-TCP + M). Animals were euthanized at 2 (n = 5) and 8 weeks (n = 5). Results indicated that in micro-CT, PCL/β-TCP + M showed the highest total augmented volume and new bone volume at 8 weeks, but there was no significant difference among four groups. Histomorphometrically, PCL, PCL/β-TCP, and PCL/β-TCP + M showed the significantly higher total augmented area compared to the control. PCL/β-TCP + M showed the highest new bone area but not statistically higher than the control. New bone formation deep inside the scaffold was observed only in β-TCP added scaffold. PCL showed high biocompatibility with great volume maintenance. Addition of β-TCP to PCL seemed to increase hydrophilicity and osteoconductivity. Developments in 3D-printed PCL material are expected. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1254-1263, 2019.

Background The in vivo molecular imaging method is a useful tool for monitoring carcinogenesis in various hepatocellular carcinoma (HCC) models, such as xenografted-, chemical induced- and transgenic mice. The tumor-specific gene expression strategy, such as transcriptional targeting, is essential for achieving a lower toxicity for normal liver tissue in therapy and the monitoring of tumor progression in diagnosis, respectively. The present study aimed to visualize spontaneously developing a-fetoprotein (AFP)-producing HCC through targeted gene expression in tumors using recombinant adenoviral vector. Methods The recombinant adenovirus vector, AdAFPfLuc (containing firefly luciferase gene driven by human AFP enhancer/promoter) was prepared. After in vitro infection by adenovirus, gene expression was confirmed using the luciferase assay, semi-quantitative reverse transcriptase-polymerase chain reaction and western blotting in AFP-producing and nonproducing cells. Tumor-bearing mice were intravenously injected with adenovirus, and bioluminescent images were obtained. Results The expression of fLuc was efficiently demonstrated by the luciferase assay in AFP-producing cells but not in AFP-nonproducing cells. AFP-producing HCC targeted gene expression was confirmed at the mRNA and protein levels. After being injected intravenously in HuH-7 xenografts and HCC-bearing diethylnitrosamine-treated mice using adenovirus, functional reporter gene expression was confirmed in tumors by in vivo bioluminescent imaging (BLI). Conclusions The recombinant adenovirus vector system can be used to monitor spontaneously developing AFP-producing HCC and to evaluate targeted gene expression in tumors by in vivo BLI in a small animal model. Copyright © 2012 John Wiley & Sons, Ltd.

123 I-FP-CIT and 18 F-FP-CIT are radiotracers which are widely used to diagnose Parkinson's disease (PD). However, to our knowledge, no studies to date have made head-to-head comparisons between 123 I-FP-CIT and 18 F-FP-CIT. Therefore, in this study, 123 I-FP-CIT SPECT/CT was compared with 18 F-FP-CIT PET/CT in the same cohort of subjects. Patients with PD and essential tremor (ET) underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual and semiquantitative analyses were conducted. The specific binding ratio (SBR) and putamen to caudate ratio (PCR) were compared between subjects who underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual analysis showed that the striatal uptake of both radiotracers was decreased in the PD group, whereas striatal uptake was intact in the ET group. The SBR between 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT showed a positive correlation (r = .78, p < .01). However, the mean SBRs on 18 F-FP-CIT PET/CT were higher than those on 123 I-FP-CIT SPECT/CT (2.19 ± .87 and 1.22 ± .49, respectively; p < .01). The PCRs in these two modalities were correlated with each other (r = .71, p < .01). The mean PCRs on 18 F-FP-CIT PET/CT were not significantly higher than those on 123 I-FP-CIT SPECT/CT (1.31 ± .19 and 0.98 ± .06, respectively; p = .06). These preliminary results indicate that the uptake of both 123 I-FP-CIT and 18 F-FP-CIT was decreased in the PD group when compared with the ET controls. Visual analyses using both methods did not affect the diagnostic accuracy in this study. However, semiquantitative analysis indicated a better contrast of 18 F-FP-CIT PET/CT relative to 123 I-FP-CIT SPECT/CT.

The antimicrobial peptide, lactoferricin, is generated upon the gastric pepsin cleavage of lactoferrin and has many basic and hydrophobic amino acid residues essential for its biological activity. To investigate the structure-antimicrobial activity relationships, the basic amino acid-rich region of bovine lactoferricin (BLFC), RRWQWRMKKLG, was selected. Using chemically synthesized BLFC and its substituted peptides, the antimicrobial activities of the peptides were tested by determining the minimal inhibitory concentration (MIC) of Escherichia coli and Bacillus subtilis and the disruption of the outer cell membrane of E. coli, and the peptide's toxicities were assayed by hemolysis. The short peptide (B3) composed of only 11 residues had similar antimicrobial activities while losing most of the hemolytic activities as compared with the 25 residue-long ones (B1 and B2). The short peptides (B3, B5 and B7) with double arginines at the N-termini had more potent antimicrobial activity than those (B4 and B6) with lysine. However, no antimicrobial and hemolytic activities were found in B8, in which all basic amino acids were substituted with glutamic acid, and in B9, in which all hydrophobic amino acids were substituted with alanine. The circular dichroism (CD) spectra of the short peptides in 30 mM SDS were correlated with their antimicrobial activities. These results suggested that the 11-residue peptide of BLFC is involved in the interaction with bacterial phospholipid membranes and plays an important role in antimicrobial activity with little or no hemolytic activity.

The membrane-disrupting properties of cecropin A (1–8)-magainin 2 (1–12) hybrid peptide, which has higher antitumor with less hemolytic activities than cecropin A (1–8)-melittin (1–12), and its analogues were assessed by measuring the induced release of vesicle-entrapped fluorescence probes. A model membrane was made of zwitterionic phospholipid (phosphatidylcholine) or the mixture of negatively and zwitterionic phospholipids (phosphatidylcholine and phosphatidylserine). The extent of leakage of the aqueous content of the phospholipid vesicles was found to have remarkable discrepancies according to the amphipathic nature of each analogue peptide. The entrapped high molecular weight solute (fluorescein-labeled immunoglobulin G, 55 kDa) also was released by the analogue which had the largest hydrophobic region and the highest amphipathic score among peptides tested. As the result of the determination of the relationships between the membrane-disrupting properties and the hydrophobicity values of peptides, it was found that the membrane-disrupting activity increased according to increasing the hydrophobicity of the peptide. The tryptophan fluorescence emission spectra and CD spectra showed that on interaction with the phospholipid vesicle, the peptide acquired the ordered structure and α-helical conformation by moving a tryptophan residue into the nonpolar environment of the phospholipid vesicle. These results suggest that the breakdown of the lipid bilayer was mediated by the α-helical amphipathic structure of the peptide interacting with the lipid bilayers as well as the by the hydrophobicity of the peptide.

Human sodium iodide symporter (hNIS) is a transmembrane protein that actively transports iodide ions into thyroid cells. hNIS is over-expressed in some cases of the thyroid cancers compared with the surrounding normal tissues and has been considered to be an attractive target for immunotherapy. The aim of this study is to determine the feasibility of utilizing the hNIS antigenic protein in enhanced-antigen-associated immunotherapy using image analysis with a gamma counter. To accomplish this, minimalistic immunogenically defined gene expression (MIDGE), either plain or coupled to a nuclear localization signal (NLS) peptide, was used as a vector system. Vaccination with MIDGE/hNIS, MIDGE/hNIS-NLS and pcDNA3.1/hNIS produced a significant increase in the number of hNIS-associated IFN-gamma-secreting CD8(+) T cells, with MIDGE/hNIS having the strongest effect. In addition, immunization with the hNIS encoding vectors induced antigen-mediated antitumor activity against NIS-expressing CT26 tumors in vivo, with the highest tumor free rate (100%) and lowest tumor growth being observed up to 40 days after the CT26/NIS tumor challenge with MIDGE/hNIS than those resulting from other immunization groups. Tumor progression could be followed noninvasively and repetitively by monitoring levels of hNIS gene expression in the tumors using scintigraphic image analysis. Overall, hNIS has a potential use as an antigen for immunization approaches, and vaccination with MIDGE/hNIS vectors is an effective means of generating hNIS-associated immune responses in mice.

The promyelocytic leukemia zinc finger (PLZF) protein has been described as a transcriptional repressor of the BTB-domain/zinc-finger family, and shown to regulate the expression of Hox genes during embryogenesis and the expression of cyclin A in the cell cycle progression. Here, a 45-kDa isoform of PLZF without a BTB domain was identified via yeast two-hybrid screening using the C-terminal region of ATP7B as bait in our determination of the biological roles of the Wilson disease protein outside of its copper-binding domain. Our immunoprecipitation experiments showed that the hepatocytic isoform of PLZF could specifically interact with the C-terminal region of ATP7B. The immunostaining of HepG2 cells revealed that the ATP7B and PLZF proteins were apparently colocalized into the trans-Golgi complexes. It was also determined that disruption of PLZF expression in the HepG2 cells affected an attenuation of ERK activity in a dose-dependent manner. The hepatocytic activities of ERK kinase were found to be enhanced as the result of PLZF or ATP7B expression, but this enhancement was abrogated by the deletion of the C-terminal region of ATP7B. Furthermore, a transgenic Drosophila strain that ectopically expressed the hepatocytic ΔBTB-PLZF exhibited phenotypic changes in eye and wing development, and these alterations were fully recovered as the result of ATP7B expression, indicating the obvious in vivo interaction between the two proteins. Those PLZF-induced abnormalities were attributed to the enhancement of ERK signaling, as was shown by phenotypic reversions with loss-of-function mutations in ERK signal transduction in Drosophila. These data suggest the existence of a mechanism that regulates ERK signaling via the C-terminus of ATP7B and the ATP7B-interacting hepatocytic PLZF. J. Cell. Biochem. 99: 719–734, 2006. © 2006 Wiley-Liss, Inc.

Headspace volatiles of Kimchi stored at 5 °C increased over a 7 d period by 20.0% and then decreased from 7 to 27 d by 8.3%. Forty volatile compounds including 18 sulfur compounds were identified in Kimchi. Lactic acid bacteria in Kimchi increased from 3.1 to 4.5 (1 × 108cfu/mL) over a 17-d period and decreased by 40% from 17 to 27 d. As the storage time increased from 2 to 27 d, pH decreased from 4.3 to 3.8, headspace oxygen decreased from 14.3 to 1.3%, and headspace carbon dioxide increased from 27.7 to 45.3%. Enzymatic reactions and chemical oxidations in Kimchi explained the changes of volatile compounds, lactic acid bacteria, pH, headspace oxygen and carbon dioxide.

In order to elucidate the structure-antibiotic activity relationships of the peptides, the three-dimensional structures of two hybrid peptides, CA(1-8) - MA(1-12) and CA(1-8) - ME(1-12) in trifluoroethanol-containing aqueous solution were investigated by NMR spectroscopy. Both CA(1-8) - MA(1-12) and CA(1-8) - ME(1-12) have strong antibacterial activity but only CA(1-8) - ME(1-12) has hemolytic activity against human erythrocytes. CA(1-8) - MA(1-12) has a hydrophobic 310-helix of only two turns combined with one short helix in the N-terminus with a flexible hinge section in between. CA(1-8) - MA(1-12) has a severely bent structure in the middle of the peptide. These structural features as well as the low hydrophobicity of CA(1-8) - MA(1-12) seem to be crucial for the selective lysis against the membrane of prokaryotic cells. CA(1-8) - ME(1-12) has an alpha-helical structure of about three turns in the melittin domain and a flexible structure with one turn in the cecropin domain connected with a flexible hinge section in between, and these might be the structural features required for membrane disruption against prokaryotic and eukaryotic cells. The central hinge region (Gly9-Ile10-Gly11) in an amphipathic antibacterial peptide is considered to play an important role in providing the conformational flexibility required for ion channel formation of the C-terminal hydrophobic alpha-helix on cell membrane.

In order to elucidate the structure-antibiotic activity relationship of cecropin A-magainin 2 and cecropin A-melittin hybrid peptides, several truncated peptides and the analogues with amino acid substitutions were synthesized and their antibacterial, antitumor and hemolytic activities of were examined. Cecropin A-magainin 2 hybrid analog, L16-CA(1-8)-MA(1-12) (termed as L-CA-MA in this study: KWKLFKKIGIGKFLHLAKKF-NH2), is known to have potent antibacterial and antitumor activity with less hemolytic activity. We found that the C-terminal region of L-CA-MA is more involved in the alpha-helical structure on cell membrane-like environment than N-terminal one by circular dichroism analysis. Deletion of the Gly-Ile-Gly sequence, the central hinge region of L-CA-MA, produced a considerable reduction in antitumor and hemolytic activity rather than an antibacterial one. The insertion of Pro, Gly-Ile or Gly-Pro in this hinge region of L-CA-MA caused retention of both antibacterial and antitumor activity while causing a significant decrease in hemolytic activity. However, the substitution with Gly-Pro-Gly instead of the Gly-Ile-Gly in CA(1-8)-MA(1-12), CA(1-8)-ME(1-12), CA(1-13)-MA(1-13) and CA(1-13)-ME(1-13) hybrids resulted in a drastic decrease in antibacterial, antitumor and hemolytic activity. The increase of hydrophobicity at position 16 in CA(1-8)-MA(1-12) by substituting Trp or Phe induced a significant increase in hemolytic activity without a considerable change in either antibacterial or antitumor activity. Therefore, these results suggested that the appropriate flexibility in the hinge region of CA-MA and CA-ME hybrid peptides and the appropriate hydrophobicity at position 16 in the hydrophobic region of CA (1-8)-MA(1-12) are important in potent antibacterial and antitumor activity with no hemolytic effect.

In order to obtain peptides having improved antimicrobial activity with low hemolytic effect, a hybrid peptide (CA-MA) composed from cecropin A (1-8) and magainin 2(1-12), and its analogues with amino acid substitutions were designed and synthesized. The antimicrobial activities against bacterial cells and hemolytic activities against human red blood cells were analyzed for each peptide. Secondary structures of the peptides in aqueous solution, 50% trifluoroethanol, and sodium dodecylsulfate micelles were estimated using circular dichroism spectroscopy. The increase in hydrophobicity or alpha-helicity of the peptides correlated with an increase in hemolytic activity rather than antimicrobial activity. The substitution of Leu for Ser at position 16 in CA-MA resulted in a remarkable increase in antimicrobial activity without a significant change in hemolytic activity. Furthermore, the increase in antimicrobial activity of the peptides was not always accompanied by the increase in hemolytic activity.

A synthetic cecropin A(1-13)-melittin(1-13) [CA-ME] hybrid peptide was known to be an antimicrobial peptide having strong antibacterial, antifungal and antitumor activity with minimal cytotoxic effect against human erythrocyte. Analogues were synthesized to investigate the influences of the flexible hinge region of CA-ME on the antibiotic activity. Antibiotic activity of the peptides was measured by the growth inhibition against bac-terial, fungal and tumor cells and vesicle-aggregating or disrupting activity. The deletion of Gln-Gly-Ile (P1) or Gly-Gln-Gly-Ile-Gly (P3) from CA-ME brought about a significant decrease on the antibiotic activities. In contrast, Gly-Ile-Gly deletion (P2) from CA-ME or Pro insertion (P5) instead of Gly-Gln-Gly-Ile-Gly of CA-ME retained antibiotic activity. This result indicated that the flexible hinge or β-bend structure provided by Gly-Gln-Gly-Ile-Gly, Gln-Gly, or Pro in the central region of the peptides is requisite for its effective antibiotic activity and may facilitate easily the hydrophobic C-terminal region of the peptide to penetrate the lipid bilayers of the target cell membrane. In contrast, P4 and P6 with Gly-Gln-Gly-Pro-Gly or Gly-Gln-Pro in the central region of the peptide caused a drastic reduction on the antibiotic activities. This result suggested that the con-secutive β-bend structure provided by Gly-Gln-Gly-Pro-Gly or Gly-Gln-Pro in the central hinge region of the peptide seems to interrupt the ion channel/pore formation on the target cell membranes.

At least 6 HLA-DRB1*12 alleles have been identified to date with nucleotide polymorphism occurring at codons 37, 57-58, 60, 67, 85 and 87. In this report, we describe the identification of another new HLA-DRB1*12 allele: DRB1*1206. This novel allele was found in an Epstein-Barr virus (EBV)-transformed Korean B-cell line "K-KT" having the HLA-phenotype A3, 24; B44, 61; Cw3; Bw4, 6; DR12, 13 during full-length cDNA isolation for cell line characterization and for production of HLA-DR recombinant proteins. The allele was identified initially by cycle sequencing of subcloned HLA-DRB full-length cDNA.

Large crystals of arylesterase from Pseudomonas fluorescens have been grown at room temperature using ammonium sulfate as a precipitant. They grow to dimensions of 0.7 × 0.7 × 0.6 mm3 within a month. The crystals belong to the trigonal space group P31 (or P32), with unit cell dimensions of a= 147.12 A and c= 131.08 A. The asymmetric unit seems to contain six molecules of dimeric aryles-terase, with corresponding crystal volume per protein mass (VM) of 2.53 A3/Da and solvent fraction of 51.5% by volume. The crystals diffract to at least 2.2 A Bragg spacing when exposed to X-rays from a rotating-anode source. X-ray data have been collected to 2.9 A Bragg spacing from native crystals. © 1993 Wiley-Liss, Inc.

The thermal stability of the alkaline protease extracellular subtilisin-type serine protease (AprP) from Pseudomonas sp. KFCC 10818 was improved by altering an amino acid residue at an autoproteolytic cleavage site. N-terminal sequence analysis of the autoproteolytic products of the protein revealed the presence of two cleavage sites, Ser-307 and Ser-331. To increase the thermal stability of the enzyme, serine residues of these sites were replaced with aspartate. The S331D mutant enzyme was successfully purified and characterized whereas the S307D mutant was not. The half-lives of the S331D mutant at 55 degrees C and 60 degrees C were 1.5 and 2.4 times longer than that of the wild-type enzyme, respectively. In addition, the catalytic efficiency was also enhanced.