Social media influencers are widely employed as a marketing strategy as they successfully attain trust from followers. Applying the social exchange theory and its principle of reciprocity, this study ...investigated whether the source characteristics of an influencer (i.e., expertise, authenticity, physical attractiveness, homophily) can function as relational resources in the formation of follower trust. Whether followers’ trust in the influencer leads to their loyalty to the influencer and desirable marketing outcomes (i.e., product attitude, purchase intention) was also examined. Results revealed that trust mediated the impacts of expertise, authenticity, and homophily on loyalty and marketing outcomes. However, physical attractiveness was not significant in building relational trust. Also, the moderating role of relationship strength was confirmed in authenticity-trust and trust-loyalty linkages. The findings suggest implications for the strategic use of influencer marketing and provide a better understanding of persuasion mechanisms manifested in influencer-follower relationships.
•Influencer-product congruence affects product attitude and advertising recognition.•Sponsorship disclosure is linked to the calculative motive inference of the influencer.•Sponsorship disclosure ...affects product attitude through a serial mediation.•Social media users infer multiple alternative motives of the influencer.
This study investigates the effects of influencer advertising attributes on consumer responses via multiple motive inference processing. Influencer-product congruence and sponsorship disclosure are manipulated as independent variables. In so doing, this study examines whether social media users infer two types of motives (Affective vs. Calculative) of the influencer derived from perceived congruence (High vs. Low) and sponsorship disclosure (Presence vs. Absence). Results suggest that influencer-product congruence can be used to enhance product attitude and reduce advertising recognition by generating a higher affective motive inference. Sponsorship disclosure can also affect product attitude in a serial mediation of calculative motive inference and advertising recognition. The multiple motive inference model explained the dual processing of influencer advertising by attributing to the prior persuasion knowledge and situational characteristics simultaneously. The findings discussed theoretical and managerial implications on native advertising on social media.
Renal renin-angiotensin system (RAS) activation is one of the important pathogenic mechanisms in the development of diabetic nephropathy in type 2 diabetes. The aim of this study was to investigate ...the effects of a sodium-glucose co-transporter 2 (SGLT-2) inhibitor, dapagliflozin, on renal RAS in an animal model with type 2 diabetes.
Dapagliflozin (1.0 mg/kg, OL-DA) or voglibose (0.6 mg/kg, OL-VO, diabetic control) (n = 10 each) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats for 12 weeks. We used voglibose, an alpha-glucosidase inhibitor, as a comparable counterpart to SGLT2 inhibitor because of its postprandial glucose-lowering effect without proven renoprotective effects. Control Long-Evans Tokushima Otsuka (LT) and OLETF (OL-C) rats received saline (n = 10, each). Changes in blood glucose, urine albumin, creatinine clearance, and oxidative stress were measured. Inflammatory cell infiltration, mesangial widening, and interstitial fibrosis in the kidney were evaluated by histological analysis. The effects of dapagliflozin on renal expression of the RAS components were evaluated by quantitative RT-PCR in renal tissue.
After treatment, hyperglycemia and urine microalbumin levels were attenuated in both OL-DA and OL-VO rather than in the OL-C group (P < 0.05). The urine angiotensin II (Ang II) and angiotensinogen levels were significantly decreased following treatment with dapagliflozin or voglibose, but suppression of urine Ang II level was more prominent in the OL-DA than the OL-VO group (P < 0.05). The expressions of angiotensin type 1 receptor and tissue oxidative stress markers were markedly increased in OL-C rats, which were reversed by dapagliflozin or voglibose (P < 0.05, both). Inflammatory cell infiltration, mesangial widening, interstitial fibrosis, and total collagen content were significantly increased in OL-C rats, which were attenuated in OL-DA group (P < 0.05).
Dapagliflozin treatment showed beneficial effects on diabetic nephropathy, which might be via suppression of renal RAS component expression, oxidative stress and interstitial fibrosis in OLETF rats. We suggest that, in addition to control of hyperglycemia, partial suppression of renal RAS with an SGLT2 inhibitor would be a promising strategy for the prevention of treatment of diabetic nephropathy.
A Ti-incorporated metal organic framework structure (MOF) MIL-125, and its amine-functionalized form, NH2-MIL-125, were directly synthesized via a solvothermal route aided by microwave heating, and ...their adsorption (H2O, CO2), separation (isoprene/2-methyl butane) and catalytic properties (olefin cycloaddition, oxidative desulfurization) were investigated. Display omitted
► Titanium-incorporated materials MIL-125 and NH2-MIL-125 were synthesized. ► NH2-MIL-125 was also prepared via microwave heating. ► CO2, N2, and H2O adsorption properties were measured at different temperatures. ► Redox and acid/base catalytic properties were investigated. ► Liquid phase separation of C5 olefin/paraffin was conducted.
A Ti-incorporated metal organic framework structure, MIL-125, and its amine-functionalized form, NH2-MIL-125, were synthesized via a solvothermal route aided by microwave heating. The samples were characterized by XRD, SEM, TGA, EA, UV–vis spectroscopy, and N2 adsorption–desorption measurements. MIL-125 was unstable in aqueous solution, but NH2-MIL-125 was stable both in water and in heptane; its hydrophilic property was further confirmed by water vapor adsorption. NH2-MIL-125 showed moderate CO2 adsorption capacity (136mgg−1) but excellent selectivity over N2 (>27:1) at 298K with a low heat of adsorption surpassing the performance of MIL-125. Four consecutive CO2 adsorption–desorption cycles over NH2-MIL-125 showed completely reversible adsorbent regeneration at 298K under a helium flow for a total duration of 550min. Catalytic properties of the materials were evaluated by cycloaddition of epichlorohydrin and oxidative desulfurization of dibenzothiophene. Finally, batch mode liquid-phase competitive separation of isoprene from 2-methyl butane was conducted, revealing high selectivity of isoprene against 2-methyl butane (ca. 7.8 and 9.7) over MIL-125 and NH2-MIL-125, respectively.
In light of the growing concern about brand dilution of luxury brands on social media, the purpose of this research was to examine the impact of brand-consumer engagement on value perceptions of ...luxury fashion brands within the context of social media marketing. The result of Study 1 demonstrated that luxury brands were inherently psychologically distant than mainstream brands. The results of Study 2 and Study 3 showed that a luxury brand with a high level (vs. low level) of brand-consumer engagement resulted lower value perceptions (i.e., social, uniqueness, and quality value perceptions) of the brand, and such relationships were mediated by decreased psychological distance. This research provides important implications for luxury brand managers and scholars that luxury fashion brands should maintain psychological distance on social media to protect the core value perceptions of the brands.
Keratin (KRT) 19 is a poor prognostic marker for hepatocellular carcinoma (HCC); however, regulatory mechanisms underlying its expression remain unclear. We have previously reported the presence of ...fibrous tumor stroma in KRT19-positive HCC, suggesting that cross-talk between cancer-associated fibroblasts (CAF) and tumor epithelial cells could regulate KRT19 expression. This was investigated in this study using an
model of paracrine interaction between HCC cell lines (HepG2, SNU423) and hepatic stellate cells (HSC), a major source of hepatic myofibroblasts. HSCs upregulated transcription and translation of KRT19 in HCC cells via paracrine interactions. Mechanistically, hepatocyte growth factor (HGF) from HSCs activated c-MET and the MEK-ERK1/2 pathway, which upregulated KRT19 expression in HCC cells. Furthermore, AP1 (JUN/FOSL1) and SP1, downstream transcriptional activators of ERK1/2, activated KRT19 expression in HCC cells. In clinical specimens of human HCC (
= 339), HGF and KRT19 protein expression correlated with CAF levels. In addition, HGF or MET protein expression was associated with FOSL1 and KRT19 expression and was found to be a poor prognostic factor. Analysis of data from The Cancer Genome Atlas also revealed KRT19 expression was closely associated with CAF and MET-mediated signaling activities. These results provide insights into the molecular background of KRT19-positive HCC that display an aggressive phenotype.
These findings reveal KRT19 expression in hepatocellular carcinoma is regulated by cross-talk between cancer-associated fibroblasts and HCC cells, illuminating new therapeutic targets for this aggressive disease.
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Plastics, including poly(ethylene terephthalate) (PET), possess many desirable characteristics and thus are widely used in daily life. However, non-biodegradability, once thought to be an advantage ...offered by plastics, is causing major environmental problem. Recently, a PET-degrading bacterium, Ideonella sakaiensis, was identified and suggested for possible use in degradation and/or recycling of PET. However, the molecular mechanism of PET degradation is not known. Here we report the crystal structure of I. sakaiensis PETase (IsPETase) at 1.5 Å resolution. IsPETase has a Ser-His-Asp catalytic triad at its active site and contains an optimal substrate binding site to accommodate four monohydroxyethyl terephthalate (MHET) moieties of PET. Based on structural and site-directed mutagenesis experiments, the detailed process of PET degradation into MHET, terephthalic acid, and ethylene glycol is suggested. Moreover, other PETase candidates potentially having high PET-degrading activities are suggested based on phylogenetic tree analysis of 69 PETase-like proteins.
Inflammation is thought to be partly responsible for metabolic syndrome (MetS). Recently, dietary inflammatory index (DII) was developed to calculate the overall inflammatory potential of a diet. The ...objective of this study was to investigate the association between DII and MetS, as well as MetS components, using nationally representative survey data. The study sample consisted of 9291 Korean adults (aged 19⁻65 years, 3682 men and 5609 women) who participated in the sixth (2013⁻2015) Korea National Health and Nutrition Examination Survey. DII values were calculated using 24-h dietary recall data. Multivariable-adjusted logistic regression analysis was performed to identify the association between DII and MetS by sex. In the multivariate logistic regression model, the top DII quartile (Q4), was positively associated with MetS prevalence in men (Q4 vs. Q1, OR = 1.40; 95% CI = 1.06⁻1.85;
for linear trend = 0.008) and in postmenopausal women (Q4 vs. Q1, OR = 1.67; 95% CI = 1.15⁻2.44;
for linear trend = 0.008). The top DII quartile was also positively associated with the prevalence of hyperglycemia in men and the prevalence of central obesity in postmenopausal women. Further studies using prospective cohorts are needed to identify the causal relationship between DII and MetS.
Purpose
To develop a fast, quantitative 3D magnetization transfer contrast (MTC) framework based on an unsupervised learning scheme, which will provide baseline reference signals for CEST and nuclear ...Overhauser enhancement imaging.
Methods
Pseudo‐randomized RF saturation parameters and relaxation delay times were applied in an MR fingerprinting framework to generate transient‐state signal evolutions for different MTC parameters. Prospectively compressed sensing–accelerated (four‐fold) MR fingerprinting images were acquired from 6 healthy volunteers at 3 T. A convolutional neural network framework in an unsupervised fashion was designed to solve an inverse problem of a two‐pool MTC Bloch equation, and was compared with a conventional Bloch equation–based fitting approach. The MTC images synthesized by the convolutional neural network architecture were used for amide proton transfer and nuclear Overhauser enhancement imaging as a reference baseline image.
Results
The fully unsupervised learning scheme incorporated with the two‐pool exchange model learned a set of unique features that can describe the MTC–MR fingerprinting input, and allowed only small amounts of unlabeled data for training. The MTC parameter values estimated by the unsupervised learning method were in excellent agreement with values estimated by the conventional Bloch fitting approach, but dramatically reduced computation time by ~1000‐fold.
Conclusion
Given the considerable time efficiency compared to conventional Bloch fitting, unsupervised learning‐based MTC–MR fingerprinting could be a powerful tool for quantitative MTC and CEST/nuclear Overhauser enhancement imaging.