Obtaining a better understanding about travel-related purchase intentions among senior users of mobile social network sites

Kim, M.J.,Lee, C.K.,Bonn, M. Butterworths ; Elsevier Science Ltd 2017 INTERNATIONAL JOURNAL OF INFORMATION MANAGEMENT - Vol.37 No.5

Although a majority of seniors continue to express interest in using mobile social network sites (MSNSs), research has yet to provide sufficient understanding of this very large market's motivations related to MSNS usage. As a viable consumer business segment, seniors are attractive enough to warrant potential MSNSs to invest necessary capital for developing tourism related MSNS designed to assist with this market's decision making and ultimately with their purchasing behavior. To address this gap, a research model was developed for this study using seniors having used MSNSs for purposes directly related to tourism and travel. Findings revealed intrinsic motivations had stronger effects on flow experience than did extrinsic motivations. Flow experience was found to have the greatest effect on subjective well-being, which in turn highly influenced purchase intention. Results documented that senior MSNS users differed significantly according to levels of anxiety attachment. Findings provide theoretical and practical contributions for tourism research, products, and services regarding senior MSNS consumers.

Endogenous conversion of n-6 to n-3 polyunsaturated fatty acids attenuates K/BxN serum-transfer arthritis in fat-1 mice

Woo, S.J.,Lim, K.,Park, S.Y.,Jung, M.Y.,Lim, H.S.,Jeon, M.G.,Lee, S.I.,Park, B.H. Butterworths ; Elsevier Science Ltd 2015 The Journal of nutritional biochemistry Vol.26 No.7

It is suggested that n-3 polyunsaturated fatty acids (PUFAs) can be used in the preventive or therapeutic management of rheumatoid arthritis (RA); however, controversial results have been reported. Here, we examined the effects of a decrease in the n-6/n-3 PUFA ratio on RA using fat-1 transgenic mice. First, we tested whether fat-1 expression modulated signaling pathways in fibroblast-like synoviocytes (FLSs) stimulated with tumor necrosis factor α (TNF-α). TNF-α activated p38 mitogen-activated protein kinase and increased phosphorylation of the signal transducer and activator of transcription 3 in wild type (WT) FLSs but not in fat-1 FLSs. Arthritis was induced by injection of K/BxN serum. Based on clinical scores, ankle thickness and pathological severity, we showed that WT mice developed clinically overt arthritis, whereas fat-1 mice showed attenuated arthritis. Moreover, fat-1 mice exhibited down-regulated local and systemic levels of inflammatory cytokines. Lastly, bone marrow-derived macrophages (BMMs) of WT mice differentiated into tartrate-resistant acid phosphatase-positive multinucleated osteoclasts, whereas the osteoclastogenenic process was suppressed in BMMs of fat-1 mice. The endogenous conversion of n-6 to n-3 PUFAs via fat-1 plays a key role in attenuation of RA; therefore, dietary supplementation of n-3 PUFAs may have therapeutic potential for the management of RA.

Exploring associations between young adults' facebook use and psychological well-being: A goal hierarchy approach

Jung, Y.,Pawlowski, S.D.,Kim, H.W. Butterworths ; Elsevier Science Ltd 2017 INTERNATIONAL JOURNAL OF INFORMATION MANAGEMENT - Vol.37 No.1

There is scant research on the broader outcomes of IT in users' life contexts beyond adoption. This study uses a goal hierarchy approach to deepen our understanding of the relationship between the use of Facebook and psychological well-being (PWB) in young adults. The study applies a mixed-method design that combines means-end analysis and regression analysis to examine data collected from laddering interviews with 161 Facebook users. The means-end chain analysis provided knowledge of the hierarchical goal structure in Facebook (i.e., activities→mediated goals→ultimate goals). Regression analysis was used to identify the relationships between the ultimate goals of Facebook use (e.g., psychological stability, belongingness) and the dimensions of PWB (e.g., self-acceptance, autonomy). The findings explain the significant association of Facebook use with well-being and the dual outcomes of enjoyment (positive in SNS; negative in users' lives). Prior research focused on relationships among abstract factors, but this study delivers a more specific and nuanced explanation of user behavior on SNSs by providing knowledge of how specific Facebook activities relate to goals and PWB.

Alginate oligosaccharide enhances LDL uptake via regulation of LDLR and PCSK9 expression

Yang, J.H.,Bang, M.A.,Jang, C.H.,Jo, G.H.,Jung, S.K.,Ki, S.H. Butterworths ; Elsevier Science Ltd 2015 The Journal of nutritional biochemistry Vol.26 No.11

The hepatic low-density lipoprotein (LDL) receptor (LDLR) plays a crucial role in lipoprotein metabolism by lowering the plasma LDL-cholesterol concentration, which reduces the risk for cardiovascular diseases. Although alginate oligosaccharide (AOS), prepared from degradation, has several pharmacological effects, it is not known whether AOS affects lipoprotein metabolism. This study was conducted to investigate whether AOS up-regulated LDLR expression and LDL uptake in vitro and in vivo, and the underlying molecular mechanism. We found that AOS increased LDLR expression and intracellular uptake of LDL by hepatocytes in a dose- and time-dependent manner. It is well established that sterol-responsive element binding protein-2 (SREBP-2) is an essential transcription factor for LDLR gene expression. AOS enhanced SREBP-2 nuclear translocation and mRNA levels. The specific role of SREBP-2 activation in AOS-induced LDLR expression was verified using an LDLR promoter construct with a sterol response element deletion. The activation of SREBP-2 by AOS is mediated by phosphatidylinositol 3-kinase/Akt/glycogen synthase kinase 3β pathways. Furthermore, we found that expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), a crucial modulator of LDLR, was down-regulated by AOS; this related to the inhibition of hepatocyte nuclear factor-1α. Treatment of mice with AOS for 2 weeks stimulated LDLR expression and reduced PCSK9 expression, resulting in decreased plasma LDL-cholesterol levels. We conclude that AOS lowered plasma LDL-cholesterol levels through regulation LDLR expression. This effect was dependent on SREBP-2 and PCSK9.

Naringin treatment induces neuroprotective effects in a mouse model of Parkinson's disease in vivo, but not enough to restore the lesioned dopaminergic system

Kim, H.D.,Jeong, K.H.,Jung, U.J.,Kim, S.R. Butterworths ; Elsevier Science Ltd 2016 The Journal of nutritional biochemistry Vol.28 No.-

<P>We recently reported that treatment with naringin, a major flavonoid found in grapefruit and citrus fruits, attenuated neurodegeneration in a rat model of Parkinson's disease (PD) in vivo. In order to investigate whether its effects are universally applied to a different model of PD and whether its treatment induces restorative effects on the lesioned nigrostriatal dopaminergic (DA) projection, we observed the effects of pre-treatment or post-treatment with naringin in a mouse model of PD. For neuroprotective effects, 6-hydroxydopamine (6-OHDA) was unilaterally injected into the striatum of mouse brains for a neurotoxin model of PD in the presence or absence of naringin by daily intraperitoneal injection. Our results showed that naringin protected the nigrostriatal DA projection from 6-OHDA-induced neurotoxicity. Moreover, similar to the effects in rat brains, this treatment induced the activation of mammalian target of rapamycin complex 1 (mTORC1), which is well known as an important survival factor for DA neurons, and inhibited microglial activation in the substantia nigra (SN) of mouse brains treated with 6-OHDA. However, there was no significant change of DA phenotypes in the SN and striatum post-treated with naringin compared with 6-OHDA-lesioned mice, despite the treatment being continued for 12 weeks. These results suggest that post-treatment with naringin alone may not be enough to restore the nigrostriatal DA projection in a mouse model of PD. However, our results apparently suggest that naringin is a beneficial natural product to prevent DA degeneration, which is involved in PD. (C) 2015 Elsevier Inc. All rights reserved.</P>

Nicotinamide improves glucose metabolism and affects the hepatic NAD-sirtuin pathway in a rodent model of obesity and type 2 diabetes

Yang, S.J.,Choi, J.M.,Kim, L.,Park, S.E.,Rhee, E.J.,Lee, W.Y.,Oh, K.W.,Park, S.W.,Park, C.Y. Butterworths ; Elsevier Science Ltd 2014 The Journal of nutritional biochemistry Vol.25 No.1

Nicotinic acid (NA) and nicotinamide (NAM) are major forms of niacin and exert their physiological functions as precursors of nicotinamide adenine dinucleotide (NAD). Sirtuins, which are NAD-dependent deacetylases, regulate glucose and lipid metabolism and are implicated in the pathophysiology of aging, diabetes, and hepatic steatosis. The aim of this study was to investigate the effects of two NAD donors, NA and NAM, on glucose metabolism and the hepatic NAD-sirtuin pathway. The effects were investigated in OLETF rats, a rodent model of obesity and type 2 diabetes. OLETF rats were divided into five groups: (1) high fat (HF) diet, (2) HF diet and 10 mg NA/kg body weight (BW)/day (NA 10), (3) HF diet and 100 mg NA/kg BW/day (NA 100), (4) HF diet and 10 mg NAM/kg BW/day (NAM 10), and (5) HF diet and 100 mg NAM/kg BW/day (NAM 100). NA and NAM were delivered via drinking water for four weeks. NAM 100 treatment affected glucose control significantly, as shown by lower levels of accumulative area under the curve during oral glucose tolerance test, serum fasting glucose, serum fasting insulin, and homeostasis model assessment of insulin resistance, and higher levels of serum adiponectin. With regard to NAD-sirtuin pathway, intracellular nicotinamide phosphoribosyltransferase, NAD, the NAD/NADH ratio, Sirt1, 2, 3, and 6 mRNA expressions, and Sirt1 activity all increased in livers of NAM 100-treated rats. These alterations were accompanied by the increased levels of proliferator-activated receptor gamma, coactivator 1 alpha and mitochondrial DNA. The effect of NA treatment was less evident than that of NAM 100. These results demonstrate that NAM is more effective than NA on the regulation of glucose metabolism and the NAD-sirtuin pathway, which may relate to the altered mitochondrial biogenesis.

Visual tracking of non-rigid objects with partial occlusion through elastic structure of local patches and hierarchical diffusion

Yi, K.M.,Jeong, H.,Kim, S.W.,Yin, S.,Oh, S.,Choi, J.Y. Butterworths ; Elsevier Science Ltd 2015 Image and vision computing Vol.39 No.-

In this paper, a tracking method based on sequential Bayesian inference is proposed. The proposed method focuses on solving both the problem of tracking under partial occlusions and the problem of non-rigid object tracking in real-time on a desktop personal computer (PC). The proposed method is mainly composed of two parts: (1) modeling the target object using elastic structure of local patches for robust performance; and (2) efficient hierarchical diffusion method to perform the tracking procedure in real-time. The elastic structure of local patches allows the proposed method to handle partial occlusions and non-rigid deformations through the relationship among neighboring patches. The proposed hierarchical diffusion method generates samples from the region where the posterior is concentrated to reduce computation time. The method is extensively tested on a number of challenging image sequences with occlusion and non-rigid deformation. The experimental results show the real-time capability and the robustness of the proposed method under various situations.

Preventive and therapeutic effects of blueberry (Vaccinium corymbosum) extract against DSS-induced ulcerative colitis by regulation of antioxidant and inflammatory mediators

Pervin, M.,Hasnat, Md.A.,Lim, J.H.,Lee, Y.M.,Kim, E.O.,Um, B.H.,Lim, B.O. Butterworths ; Elsevier Science Ltd 2016 The Journal of nutritional biochemistry Vol.28 No.-

<P>Inflammatory bowel disease (IBD) is an inflammatory disorder caused by hyperactivation of effector immune cells that produce high levels of proinflammatory cytokines. The aims of our study were to determine whether orally administered blueberry extract (BE) could attenuate or prevent the development of experimental colitis in mice and to elucidate the mechanism of action. Female Balb/C mice (n=7) were randomized into groups differing in treatment conditions (prevention and treatment) and dose of BE (50 mg/kg body weight). Acute ulcerative colitis was induced by oral administration of 3% dextran sodium sulfate for 7 days in drinking water. Colonic mucosal injury was assessed by clinical, macroscopic, biochemical and histopathological examinations. BE significantly decreased disease activity index and improved the macroscopic and histological score of colons when compared to the colitis group (P<.05). BE markedly attenuated myeloperoxidase accumulation (colitis group 54.97 +/- 2.78 nmol/mg, treatment group 30.78 +/- 1.33 nmol/mg) and malondialdehyde in colon and prostaglandin E2 level in serum while increasing the levels of superoxide dismutase and catalase (colitis group 11.94 +/- 1.16 U/ml, BE treatment group 16.49 +/- 0.39 U/ml) compared with the colitis group (P<.05). mRNA levels of the cyclooxygenase (COX)-2, interferon-gamma, interleukin (IL)-1 beta and inducible nitric oxide synthase cytokines were determined by reverse transcriptase polymerase chain reaction. Immunohistochemical analysis showed that BE attenuates the expression of COX-2 and IL-1 beta in colonic tissue. Moreover, BE reduced the nuclear translocation of nuclear transcription factor kappa B (NF-kappa B) by immunofluorescence analysis. Thus, the anti-inflammatory effect of BE at colorectal sites is a result of a number of mechanisms: antioxidation, down regulation of the expression of inflammatory mediators and inhibition of the nuclear translocation of NF-kappa B. (C) 2015 Elsevier Inc. All rights reserved.</P>

Special section on generative smart tourism systems and management: Man-machine interaction

Koo, C.,Yoo, K.H.,Lee, J.N.,Zanker, M. Butterworths ; Elsevier Science Ltd 2016 INTERNATIONAL JOURNAL OF INFORMATION MANAGEMENT - Vol.36 No.6

Inhibition of tumor progression by oral piceatannol in mouse 4T1 mammary cancer is associated with decreased angiogenesis and macrophage infiltration

Song, H.,Jung, J.I.,Cho, H.J.,Her, S.,Kwon, S.H.,Yu, R.,Kang, Y.H.,Lee, K.W.,Park, J.H.Y. Butterworths ; Elsevier Science Ltd 2015 The Journal of nutritional biochemistry Vol.26 No.11

Piceatannol, a polyphenol which exhibits anticancer activities, is found in grapes, red wine and berries. It has been shown to inhibit several transcription factor pathways. The present study was conducted to determine whether oral administration of piceatannol inhibits mammary tumor progression. 4T1 mammary carcinoma cells were injected into the mammary fat pad of syngeneic female BALB/c mice. Starting 1 day later, piceatannol (10- or 20-mg/kg body weight/day) was administered by oral gavage for 30 days. Piceatannol treatment reduced tumor growth. In tumor tissues, piceatannol treatment reduced the expression of transcription factors P-NFκB p65, P-STAT3 and HIF-1α and multiple proteins involved in regulation of cell cycle progression (Ki67, cyclin D1, cyclin A, CDK2, CDK4), angiogenesis (VEGF-A, VEGFR-2, VE-cadherin, CD31) and lymphangiogenesis (VEGF-C, LYVE-1), as well as macrophage infiltration. Piceatannol significantly increased apoptotic cells and expression of both Bax and cleaved caspase-3 but reduced Bcl-2 expression in tumor tissues. In addition, piceatannol reduced the number and volume of pulmonary tumor nodules and expression of MMP-9 in both lung and tumor. It also reduced tissue levels of cytokines/chemokines, including M-CSF and MCP-1. In vitro results revealed that piceatannol inhibited migration of 4T1 cells and monocytes, as well as secretion of MCP-1 and M-CSF by 4T1 cells. 4T1 cell-conditioned medium stimulated monocyte migration, which was suppressed by a CCR2 antibody. These results indicate that alteration in tumor microenvironment (macrophages, transcription factors, etc.) is an important mechanism by which piceatannol inhibits tumor proliferation, angiogenesis and lymphangiogenesis, leading to suppression of mammary tumor growth and metastasis.