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Charcot-Marie-Tooth disease type 2A (CMT2A) is the most common hereditary axonal neuropathy caused by mutations in MFN2 encoding Mitofusin-2, a multifunctional protein located in the outer mitochondrial membrane. In order to study the effects of a novel MFN2K357T mutation associated with early onset, autosomal dominant severe CMT2A, we generated a knock-in mouse model. While Mfn2K357T/K357T mouse pups were postnatally lethal, Mfn2+/K357T heterozygous mice were asymptomatic and had no histopathological changes in their sciatic nerves up to 10 months of age. However, immunofluorescence analysis of Mfn2+/K357T mice revealed aberrant mitochondrial clustering in the sciatic nerves from 6 months of age, in optic nerves from 8 months, and in lumbar spinal cord white matter at 10 months, along with microglia activation. Ultrastructural analyses confirmed dysmorphic mitochondrial aggregates in sciatic and optic nerves. After exposure of 6-month-old mice to lipopolysaccharide, Mfn2+/K357T mice displayed a higher immune response, a more severe motor impairment, and increased CNS inflammation, microglia activation, and macrophage infiltrates. Overall, ubiquitous Mfn2K357T expression renders the CNS and peripheral nerves of Mfn2+/K357T mice more susceptible to mitochondrial clustering, and augments their response to inflammation, modeling some cellular mechanisms that may be relevant for the development of neuropathy in patients with CMT2A.

Objectives Despite the evidence supporting the use of vitamin D supplements for managing atopic dermatitis (AD), no meta-analysis providing definite conclusions in this field has been reported. The purpose of the present study was to conduct a systematic review and meta-analysis of all controlled studies of vitamin D for treating AD to elucidate the efficacy of vitamin D for alleviating the symptoms of AD. Methods Literature searches were conducted using Ovid-MEDLINE, EMBASE, Web of Science, Cochrane Library, and Korean and Chinese databases. Search terms used were “vitamin D”, “atopic dermatitis”, “randomized”, “controlled trial”, and “clinical trial”. Random effects models were used to calculate the mean difference, with 95% confidence intervals to analyze the effects of vitamin D supplementation for severity of AD. Results Initial searches yielded 266 citations. Of these original results, nine met specific selection criteria. Four of the randomized controlled trials compared the efficacy of vitamin D with a placebo on severity of AD and were included in the meta-analysis. The vitamin D supplementation interventions showed a higher mean difference in severity of AD symptoms (mean difference = −5.81, 95% CI: −9.03 to −2.59, P = 0.0004, I2 = 50%). Conclusions Vitamin D has a potentially significant role for improving the symptoms of AD. The results from this study suggest that vitamin D supplementation may help ameliorate the severity of AD, and can be considered as a safe and tolerable therapy. However, larger-scale studies over a longer duration of treatment are needed to confirm this conclusion.

Jeju citrus, which contains an abundance of calcium and vitamin, was used to develop fermented citrus peel extract. A total of seven probiotic strains were applied to tangerine dermis to select the best growing bacteria in citrus peel extracts. B. longum, B. bifidum, and L. mesenteroides were found to grow best in citrus peel extract culture containing glucose, yeast extracts, peptone, and potassium phosphate. Citrus peel extract culture consisting of 1% yeast extract, 5% peptone, and 0.1% phosphate was the best environment for growth of probiotics. The pH, acidity, and viable cell numbers of these fermented extracts were measured. The initial pH level of fermented extracts with nutrients was 5.25 and dropped rapidly to 3.39 after 72 hours of fermentation. The acidity of fermented extracts increased to 4.08 % after 72 hours of fermentation, and the viable cell number in fermented extracts after refrigeration for 2 weeks was . The antimicrobial activity of citrus peel fermented extracts against Campylobacter jejuni was determined, and concentrations more than 25,000 ppm showed antimicrobial activity.

The enzyme 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) is known to catalyse inactive glucocorticoids into active forms, and its dysregulation in adipose and muscle tissues has been implicated in the development of metabolic syndrome. To delineate the molecular mechanism by which active cortisol has an antagonizing effect against insulin, we optimized the metabolic production of cortisol and its biological functions in myotubes (C2C12). Myotubes supplemented with cortisone actively catalysed its conversion into cortisol, which in turn abolished phosphorylation of Akt in response to insulin treatment. This led to diminished uptake of insulin-induced glucose. This was corroborated by the application of 11β-HSD1 inhibitor glycyrrhetinic acid and a glucocorticoid receptor antagonist RU-486, which reversed completely the antagonizing effects of cortisol on insulin action. Therefore, development of specific inhibitors targeting 11β-HSD1 might be a promising way to improve impaired insulin-stimulated glucose uptake. Copyright © 2013 John Wiley & Sons, Ltd.

Diarrheal diseases constitute one of the major causes of morbidity and mortality in infants and young children globally. One of the main microorganisms causing diarrheal diseases is Campylobacter jejuni. For treatment of these diseases, Portulaca oleracea has been widely used as a folk remedy for a long time. This study was performed to investigate the antimicrobial activity of P. oleracea against gastroenteritis pathogens including C. jejuni. P. oleracea was extracted with petroleum ether, chloroform, ethylacetate, methanol, and hot water. The antimicrobial activity of the P. oleracea extracts was determined using the paper disc method, minimum inhibitory concentration, and the liquid culture method. The 10 ㎎/㎖ ethylacetate extract showed the strongest antimicrobial activity against Salmonella typhimurium, Salmonella enteriditis, and Shigella spp.. The hot water extract from P. oleracea showed the highest anti-microbial activity against C. jejuni at 10 ～ 20 ㎎/㎖. The hot water extract of P. oleracea retarded the growth of C. jejuni for 36 hr at 42℃.Key words: Portulaca oleracea, Campylobacter jejuni, antimicrobial activity

One of the main microorganisms causing diarrheal diseases is Campylobacter jejuni. Purslane or Portulaca oleracea is an edible plant containing polyphenols that has been widely used as a folk remedy for treatment of diarrhea for a long time. This study was performed to investigate the antimicrobial activity of fermented P. oleracea extracts made with probiotics and plant-origin lactic acid bacteria(PLAB) isolated from P. oleracea against C. jejuni. Lactobacillus rhamnosus, L. acidophilus, L. bulgaricus, L. delbrueckii, L. plantarum, Leuconostoc mesenteroides and Bifidobacterium longum were applied to P. oleracea to make a fermentation broth of purslane. Leuconostoc mesenteroides and the lactic acid bacteria isolated from P. oleracea grew best in the fermentation broth of P. oleracea extracts when the broth was combined with 2% yeast extract, 1% peptone, and 0.05 to 1% potassium phosphate. The number of viable cells in the fermentation broth containing purslane extracts after 48 hours increased to 1×10 12 CFU/㎖ and remained at 1.3×10 10 CFU/㎖ after refrigeration for 2 weeks. The pH and acidity of purslane-fermented broth after 48 hours of fermentation was 3.7 and 3.14, respectively, which show that the fermentation broth was within the range of the general standards of fermented dairy products. The antimicrobial activity of the fermented P. oleracea extracts was determined using the liquid culture method. The 10 ㎎/㎖ concentration of the fermented P. oleracea extract made with Leuconostoc mesenteroides and the lactic acid bacteria isolated from purslane showed the strongest antimicrobial activity against C. jejuni. The fermentation broth of purslane with the probiotics retarded the growth of C. jejuni for 48 hours at 42℃.

In this study we investigated the inhibitory effects and possible mechanisms of action of 8'-hydroxydaidzein and 3'-hydroxydaidzein, two ortho-dihydroxyisoflavone derivatives from Korean fermented soybean paste, on melanogenesis in B16 murine melanoma cells. The two hydroxydaidzeins reduced melanin synthesis comparably to treatment with kojic acid, a proven whitening agent, in B16 melanoma cells. Furthermore, when in vitro human skin equivalents were treated with the hydroxydaidzeins, the levels of melanogenesis were significantly reduced relative to a kojic acid control. The RT-PCR results demonstrated that depigmentation was due to transcriptional repression of several melanogenesis genes, including microphthalmia-associated transcription factor (MITF), by the hydroxydaidzeins. The immunoblotting results confirmed that diminution of MITF expression subsequently decreased expression of tyrosinase, and tyrosinase-related proteins 1 and 2. Cumulatively, these results suggest that hydroxydaidzeins would be potent attenuators of melanin synthesis as well as effective inhibitors of hyperpigmentation in human skin. Copyright © 2011 John Wiley & Sons, Ltd.

This study was performed to investigate the effect of Portulaca oleracea extract on the antioxidant and antimicrobial activities against Helicobacter pylori. The each solvent extracts prepared from Portulaca oleracea were investigated by measuring total phenolic compounds, electron donating ability, superoxide dismutase-like ability and thiobarbituric acid reactive substances The herb extractor extract yielded the highest content of total phenolic compounds(72.2 ㎎%). The electron donating abilities(EDA) of ethyl acetate and methanol extracts showed high antioxidant activity. The superoxide dismutase (SOD)-like abilities of ethyl acetate and petroleum ether extracts also showed some activity. The antioxidant activity of thiobarbituric acid reactive substances was not significant. The petroleum ether extract of Portulaca oleracea showed the highest antimicrobial activity at 10,000 ppm concentration.

This study investigated the effects of mulberry fruit extract on antioxidant activities and the alleviation of an alcohol- induced hangover, which was measured with alcohol dehydrogenase(ADH) enzyme activity. The antioxidative capacity of each mulberry extract was measured by total phenolic compounds, electron donating ability, superoxide dismutase-like ability, thiobarbituric acid reactive substances, and nitrite scavenging ability. The 60% methanol extract yielded the highest total phenolic compounds. The electron donating ability of the 40% ethanol and 40% methanol extracts were 68% and 67%, respectively. The superoxide dismutase-like abilities of the 40% methanol and 40% ethanol extracts were 30% and 28%, respectively, when extracts were assayed at 2.5 ㎎/㎖. The nitrite scavenging ability of the 60% ethanol and 40% methanol extracts were 98% and 97%, respectively. The 60% ethanol extract yielded the highest ADH.Key words: antioxidative activity, mulberry, alcohol dehydrogenase

The present study was performed to investigate antioxidant activities of Korean edible wild extracts. In water and methanol extracts of edible wild plants, total polyphenol content of water and methanol extracts ranged 4.6~183.8 and 8.2~270.1 mg/g, respectively. Radical scavenging activity against DPPH and ABTS radicals was observed to be high in Lysimachia barystachys, Aceriphyllum rossii, Securinega suffruticosa, Sedum kamtschaticum, and Pedicularis resupinata. Pedicularis resupinata, Securinega suffruticosa, Patrinia villosa, and Solidago virga-aurea var. asiatica showed effective SOD-like activity. There was significant correlation between polyphenol content and DPPH and ABTS radical scavenging activities, and SOD-like activity. Plant extracts such as Pedicularis resupinata, Securinega suffruticosa, Rhapontica uniflora, Lysimachia barystachys, and Aceriphyllum rossii had higher polyphenol content, radical scavenging, and SOD-like activity. These results indicate that Korean edible wild plants may be useful as potential antioxidant sources for improving human antioxidant defense system.

The activation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) via phosphorylation in the hippocampus is an important signaling mechanism for enhancing memory processing. Although melatonin is known to increase CREB expression in various animal models, the signaling mechanism between melatonin and CREB has been unknown in vitro. Thus, we confirmed the signaling pathway between the melatonin receptor 1 (MT1) and CREB using melatonin in HT-22 cells. Melatonin increased MT1 and gradually induced signals associated with long-term memory processing through phosphorylation of Raf, ERK, p90RSK, CREB, and BDNF expression. We also confirmed that the calcium, JNK, and AKT pathways were not involved in this signaling pathway by melatonin in HT-22 cells. Furthermore, we investigated whether melatonin regulated the expressions of CREB-BDNF associated with long-term memory processing in aged HT-22 cells. In conclusion, melatonin mediated the MT1-ERK-p90RSK-CREB-BDNF signaling pathway in the in vitro long-term memory processing model and increased the levels of p-CREB and BDNF expression in melatonin-treated cells compared to untreated HT-22 cells in the cellular aged state. Therefore, this paper suggests that melatonin induces CREB signaling pathways associated with long-term memory processing in vitro.

Objective Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the nuclear hormone receptor superfamily. Treatment of PPARγ ligands has been shown to inhibit the growth of various human cancer cells. However, it has not been reported whether human cervical carcinoma cells express PPARγ. In this study, we investigated the expression of PPARγ in human normal cervix and cervical carcinoma tissues, and as well as the effect of PPARγ ligands on cervical cancer cells survival. Methods Fresh cervical tissues from a study group of 10 study patients diagnosed with cervical carcinoma were analyzed for the expression of PPARγ using real-time RT-PCR and Western blot analysis. Immunohistochemical staining for PPARγ was also performed on the serial sections of 40 cervical carcinomas. In addition, we evaluated the feasibility of PPARγ ligands, as a potential therapeutic drug against cervical cancer cells using MTT assay and FACS analysis. Results We found that there were lower expression levels of PPARγ mRNA and protein in cervical carcinoma tissues than in normal cervical tissues. The extent and intensity of immunoreactive PPARγ in normal cervix tissues were statistically much greater than those of carcinoma tissues. In order to study effects of PPAR ligand on cell proliferation, we chose ciglitizone that showed very potent growth inhibitory effects on the proliferation of two human cervical cancer cell lines (C-33-A and C-4II). C-4II cells express high expression of PPARγ, while C-33A cells express low level of PPARγ. Treatment with ciglitizone inhibited the growth of C-4II cells in a dose-dependent manner, while the growth inhibitory effect of ciglitizone was much less in C-33A cells. In order to test whether ciglitizone-induced growth suppressive effects on cervical cancer cell lines is PPAR-dependent, we treated cervical cancer cells with ciglitizone and/or GW9662 (a PPARγ antagonist). No significant difference in cell survival was found in cells treated with ciglitizone alone vs. co-treated with ciglitizone and GW9662. GW9662 alone did not induce any cell growth arrest in the cells that we used (data not shown). Thus, we concluded that growth suppressive effects by ciglitizone may not be dependent upon status of PPAR expression. To clarify the mechanism by which ciglitizone inhibits the growth of cervical carcinoma cells, flow cytometry and Western blotting assay were performed. As results, we demonstrated that a large portion of C-4II cells (but not in C-33A) after ciglitizone treatment were arrest at G1 phase with the induction of p21 Cip1/Waf1 and p27 kip1 protein. Conclusions These results suggest that PPARγ is down-regulated in multiple human cervical cancer tissues and cell lines. Ciglitizone may suppress human cervical cancer cells in PPAR-independent manner.

This study was performed to investigate the antimicrobial activity of the Rubia akane Nakai extract against food-borne pathogens. First, the Rubia akane Nakai was extracted with methanol at room temperature and the fractionation of the methanol extract was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol. The antimicrobial activity of the Rubia akane Nakai extract was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extract of Rubia akane Nakai showed the highest antimicrobial activity against Bacillus cereus and Pseudomonas aeruginosa. Synergistic antimicrobial effect was observed when Rubia akane Nakai extract was mixed with Viscum album var. coloratum extract as compared to each extract alone. Finally, the growth inhibition curves were determined by using methanol extract of Rubia akane Nakai against Bacillus cereus and Pseudomonas aeruginosa. The methanol extract of Rubia akane Nakai had strong antimicrobial activity against Pseudomonas aeruginosa at the concentration of 4,000 ppm. At this concentration, the growth of Pseudomonas aeruginosa was retarded more than 72 hours and up to 48 hours for Bacillus cereus. From these results, it was concluded that the methanol extract of Rubia akane Nakai inhibited effectively Bacillus cereus and Pseudomonas aeruginosa.

This study was performed to investigate the antimicrobial effect of the Hedyotis diffusa extracts against food-borne pathogens. First, the Hedyotis diffusa was extracted with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol respectively. The antimicrobial activity of the Hedyotis diffusa extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extracts of Hedyotis diffusa showed the highest antimicrobial activity against Staphylococcus aureus and Shigella flexneri. Synergistic effect in inhibition was observed when Hedyotis diffusa extract was mixed Sophora subprostrata extract as compared to each extracts alone. Finally, the growth inhibition curves were determined by using ethyl acetate extracts of Hedyotis diffusa against Staphylococcus aureus and Salmonella Typhimurium. The methanol extract of Hedyotis diffusa had strong antimicrobial activity against Staphylococcus aureus at the concentration of 4,000 ppm. At this concentration, the growth of Staphylococcus aureus was retarded more than 36 hours and up to 24 hours for Salmonella Typhimurium. In conclusion, the methanol extracts of Hedyotis diffusa inhibit efficiently Staphylococcus aureus and Salmonella Typhimurium.

【This study was performed to investigate the antimicrobial effects of Portulaca oleracea extracts against food-borne pathogens. First, the Portulaca oleracea was extracted with methanol at room temperature, and then further fractionated by using petroleum ether, chloroform, ethyl acetate and methanol, respectively. The antimicrobial activity of the Portulaca oleracea extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Portulaca oleracea showed the highest antimicrobial activity against Staphylococcus aureus and Shigella dysenteriae. There was also a synergistic effect of the combined extracts of Portulaca oleracea and Indigofera kirilowii as compared to each extract alone. Finally, the growth inhibition curve of ethyl acetate extracts of Portulaca oleracea against Staph­ylococcus aureus and Shigella dysenteriae was determined The ethyl acetate extract of Portulaca oleracea showed strong antimicrobial activity against Staphylococcus aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate extract from Portulaca oleracea, retarded the growth of S. aureus by more than 24 hand Shigella dysenteriae up to 12 h at $37^{\circ}C$ .】

Homogenously dispersed TiO2/poly(methyl methacrylate) (PMMA) composite microspheres were produced in the size range of 1–10µm and the interfacial characteristics of TiO2 and PMMA in suspension polymerization were considered. In electron microscopy observation, it was found that TiO2 nanoparticles were embedded homogeneously in the PMMA phase. This study elucidates that the interfacial compatibility between TiO2 and PMMA played a decisive role in producing the composite microspheres structured with inner TiO2 and continuous PMMA, which was achieved by treating the surface of the TiO2 particles hydrophobically. The TiO2/PMMA composite microspheres produced showed good ability to protect against UV rays and are therefore of great usefulness in cosmetic formulations.

Aim The aim is to assess the effect of desensitizing toothpaste on dentin hypersensitivity. Methods We searched PubMed, CENTRAL, and Embase on December 20, 2013. Results Out of the 626 articles searched, a total of 31 randomized controlled clinical trials were included. The Standardized mean differences (SMD) for potassium-containing toothpaste (n = 8) was -1.28 (95% Confidence interval (CI) -2.05 to -0.51; I(2) = 93%); Stannous fluoride- (n = 6) was -1.37 (95% CI, -2.30 to -0.44; I(2) = 95%); Potassium and stannous fluoride- (n = 3) was -2.50 (95% CI, -4.10 to -0.91; I(2) = 95%); Calcium sodium phosphosilicate- (n = 4) was -2.36 (95% CI, -3.72 to -1.00; I(2) = 92%); Arginine- (n = 8) was -3.25 (95% CI, -3.87 to -2.63; I(2) = 86%). The desensitizing effect was favoured in the intervention group treated with potassium-, stannous fluoride-, potassium and stannous fluoride-, calcium sodium phosphosilicate-, and arginine-containing toothpaste compared to placebo. Whereas, strontium-containing toothpaste (SMD, 0.05; 95% CI, -0.34 to 0.44; I(2) = 64%) was found to have no statistically significant desensitizing effect in the meta-analysis of four studies. Conclusions The study reports that there is sufficient evidence to support the use of potassium-, stannous fluoride-, potassium and stannous fluoride-, calcium sodium phosphosilicate-, and arginine-containing desensitizing toothpastes for dentin hypersensitivity, but not the use of strontium-containing desensitizing toothpaste.

Background Postmenopausal women experience estrogen deficiency-related menopausal symptoms (e.g., hot flashes and mood swings) and a dramatic increase in the incidence of chronic diseases. Although estrogen-replacement therapy (ERT) can reduce mortality from cardiovascular disease and improve osteoporosis and menopausal symptoms, its side effects have limited recent use. This study investigated the estrogen-like activity of aqueous extract from Agrimonia pilosa Ledeb. Methods The estrogenic activity of A. pilosa was investigated by using several in vitro assays. The binding activity of A. pilosa on estrogen receptors was examined using a fluorescence polarization-based competitive binding assay. The proliferative activity of A. pilosa was also examined using MCF-7 cells. Furthermore, the effect of A. pilosa on the expression of 3 estrogen-dependent genes was assessed. Results Using liquid chromatography-mass spectrometry, the 3 major peaks of A. pilosa aqueous extract were identified as apigenin-hexose, luteolin-glucuronide, and apigenin-glucuronide. The aqueous extract induced the proliferation of estrogen receptor-positive MCF-7 cells (p A. pilosa-stimulated proliferation was blocked on adding the estrogen antagonist ICI 182,780. Moreover, A. pilosa treatment increased the mRNA expression of the estrogen-responsive genes pS2 and PR (p Conclusions These results suggest A. pilosa can be used to improve estrogen deficiency-related menopausal symptoms or to treat diseases in postmenopausal women.

The foodborne pathogenStaphylococcus aureus is distinguished by its ability to grow within environments of extremely high osmolarity (e.g., foods with low water activity values). In the present study, we examined the accumulation of intracellular organic solutes withinS. aureus strain ATCC 12600 when cells were grown in a complex medium containing high concentrations of NaCl. Consistent with previous reports [Measures JC (1975) Nature 257:398–400; Koujima I, et al. (1978) Appl Environ Microbiol 35:467–470; and Anderson CB, Witter LD (1982) Appl Environ Microbiol 43:1501–1503], intracellular proline was found to accumulate to high concentrations. However, NMR spectroscopy of cell extracts revealed glycine betaine to be the predominant intracellular organic solute accumulated within cells grown at high osmolarity. In additional experiments, we examined the growth rate ofS. aureus in a defined medium of high osmolarity and found it to be stimulated significantly by the presence of either exogenous proline or glycine betaine. Highest growth rates were obtained when the defined medium was supplemented with glycine betaine.

(−)-Epigallocatechin-3-gallate (EGCG), a major polyphenolic substance found in green tea, is well recognized to be beneficial for human health. However, it is still controversial as to what dose of this compound is indeed good for human health. Though some recent studies have interestingly reported various beneficial effects of EGCG in cell culture system, however, plasma levels of EGCG attainable by oral regular intake in humans are normally in nanomolar range. However, potential side effects of EGCG when administered parenterally at higher concentration have not been thoroughly tested. Here, we evaluated the effect of EGCG on ATP-sensitive potassium (K ATP ) channels expressed in Xenopus oocytes. EGCG inhibited the activity of the Kir6.2/SUR1 and Kir6.2ΔC36 channels with IC 50 of 142 ± 37 and 19.9 ± 1.7 μM, respectively. Inhibition of EGCG was also observed in Kir6.2/SUR2A or Kir6.2/SUR2B channels. Notably, (−)-epicatechin-3-gallate (ECG), another major polyphenolic substance in green tea, was found to reduce the channel activity with greater potency than EGCG. In contrast to EGCG and ECG, which have the gallic acid-ester moiety in their own structures, (−)-epigallocatechin and (−)-epicatechin exhibited very weak inhibition of the K ATP channel. Collectively, these results suggest that the gallate-ester moiety of epicatechins may be critical for inhibiting the K ATP channel activity via the pore-forming subunit Kir6.2 and this may be a possible mechanism by which green tea extracts or EGCG may cause unexpected side effects at micromolar plasma level.

Staphylococcus aureus accumulates proline and glycine betaine when cells are grown at low water activity. In the present study, we have identified a high-affinity glycine betaine transport system in this bacterium. Optimal activity for this transport system was measured in the presence of high NaCl concentrations, but transport activity was not stimulated by high concentrations of other solutes.

The present study was performed to investigate antioxidant, anticancer, and antimicrobial activities of four Korean sweet potato variaties and to identify the changes in these biological activities under different cooking conditions. Total polyphenol content was 3.8-73.6 mg/g in 80% ethanol extracts of sweet potatoes. The polyphenol content was highest Sinjami variety (p ＜ 0.05). Radical scavenging activity against DPPH and ABTS ·+ was high in Sinjami (p ＜ 0.05) and the ethanol extract from Sinjami also showed effective superoxide dismutase (SOD)-like activity, which decreased significantly by steaming and roasting (p ＜ 0.05). Ethanol extracts from the four sweet potato variaties did not inhibit cancer cell growth in MCF-7 or HepG2 cells at concentrations of 1, 10, and 100 µg/mL. Of the investigated sweet potato variaties, only Sinjami exhibited strong antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium. The antimicrobial activity of Sinjami against E. coli, St. aureus, and S. typhimurium decreased following steaming and roasting (p ＜ 0.05). These results indicate that the Sinjami Korean sweet potato had higher polyphenol content, radical scavenging activity, SOD-like activity, and antimicrobial activity than those of the other variaties and consuming raw Sinjami might be beneficial for maintenance of biological activities. (Korean J Nutr 2012; 45(1): 12 ~ 19)

The food-borne pathogen Staphylococcus aureus is distinguished from other food-borne pathogens by its ability to grow at water activity values below 0.90. Previous studies have indicated that proline accumulation mediated by transport represents a primary osmoregulatory strategy utilized by this bacterium (C. B. Anderson and L. D. Witter, Appl. Environ, Microbiol. 43:1501-1503, 1982; I. Koujima, H. Hayashi, K. Tomochika, A. Okabe, and Y. Kanemasa, Appl. Environ. Microbiol. 35:467-470, 1978; K. J. Miller, S. C. Zelt, and J.-H. Bae, Curr. Microbiol. 23:131-137, 1991). In this study, we demonstrate the presence of two proline transport systems within whole cells of S. aureus, a high-affinity transport system (Km, 7 microM) and a low-affinity transport system (Km, 420 microM). Our results indicate that the low-affinity proline transport system is osmotically activated and is the primary system responsible for the accumulation of proline by this pathogen during growth at low water activity.

Deterioration of long-term dentin adhesion durability is thought to occur by hydrolytic degradation within hydrophilic domains of the adhesive and hybrid layers. This study investigated the hypothesis that priming the collagen network with an organic solvent displace water without collapse and thereby obtain good bond strength with an adhesive made of hydrophobic monomers and organic solvents. Three experimental adhesives were pre- pared by dissolving two hydrophobic monomers, bisphenol-A-glycidylmethacrylate (Bis-GMA) and triethylenegly- col dimethacrylate (TEGDMA), into acetone, ethanol or methanol. After an etching and rinsing procedure, the adhesives were applied onto either wet dentin surfaces (wet bonding) or dentin surfaces primed with the same solvent (solvent-primed bonding). Microtensile bond strength (MTBS) was measured at 48 hrs, 1 month and after 10,000 times of thermocycles. The bonded interfaces were evaluated using a scanning electron microscope (SEM). Regardless of bonding protocols, well-developed hybrid layers were observed at the bonded interface in most speci- mens. The highest mean MTBS was observed in the adhesive containing ethanol at 48 hrs. With solvent-primed bonding, increased MTBS tendencies were seen with thermocycling in the adhesives containing ethanol or methanol. However, in the case of wet bonding, no increase in MTBS was observed with aging.