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Perfluoroalkyl substances (PFASs) in shallow groundwater are increasingly being studied due to the global occurrence, environment persistence, bioaccumulation, and potential human health risk. In this research, 16 PFAS (11 perfluorinated carboxylic acids and 5 perfluorinated sulfonic acids) concentrations in groundwater were quantified to obtain information on geographical distribution and PFAS detection pattern for 4 years in South Korea. In the results, groundwater PFAS concentration ranged from non-detectable to average 45.2 ng/L (sum of PFASs). The major PFAS compounds were perfluorooctanoic acid (PFOA), perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS). The short chain (C < 8) PFASs were more prevalent than long chain (C > 8) PFASs in shallow groundwater. However, the detection patterns of 15 PFASs were different for each aquifer. Subsequently, through a health risk assessment, a non-carcinogenic risk level through ingestion, inhalation, and dermal contact for PFOA and PFOS was determined at 10−1, and it presents the need for PFAS management of groundwater.

A shape detail transfer is the process of extracting the geometric details of a source region and transferring it onto a target region. In this paper, we present a simple and effective method, called GeoStamp, for transferring shape details using a Poisson equation. First, the mean curvature field on a source region is computed by using the Laplace–Beltrami operator and is defined as the shape details of the source region. Subsequently, the source and target regions are parameterized on a common 2D domain, and a mean curvature field on the target region is interpolated by the correspondence between two regions. Finally, we solve the Poisson equation using the interpolated mean curvature field and the Laplacian matrix of the target region. Consequently, the mean curvature field of the target region is replaced with that of the source region, which results in the transfer of shape details from the source region to the target region. We demonstrate the effectiveness of our technique by showing several examples and also show that our method is quite useful for adding shape details to a surface patch filling a hole in a triangular mesh.

Increasing evidence is suggesting that amyloid-β peptide (Aβ), a characteristic of Alzheimer’s disease (AD), induces oxidative stress and mitochondrial dysfunction, leading to neuronal death. This study aimed to demonstrate the antioxidant and anti-apoptotic effects of fucoxanthin, a major marine carotenoid found in brown algae, against neuronal injury caused by Aβ. Non-toxic dose range of fucoxanthin (0.1–5 µM) were selected for the neuroprotective study against Aβ25–35. The PC12 cells were pretreated with different concentrations of fucoxanthin for 1 h before being exposed to 10 µM Aβ25–35 for another 24 h. The present results showed that fucoxanthin inhibited Aβ25-35-induced cell death by recovering cell cycle arrest and decreasing intracellular reactive oxygen species (ROS) level. The compound enhanced mitochondrial recovery and regulated apoptosis related proteins including B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) from Aβ25-35-induced oxidative stress. Concomitantly, fucoxanthin increased the expression of nuclear factor E2-related factor 2 (Nrf2) and its downstream phase II detoxifying enzymes including NADPH: quinone oxidoreductase-1 (NQO-1), glutamate cysteine ligase modifier subunit (GCLm), and thioredoxin reductase 1 (TrxR1), whereas it decreased the expression of cytoplasmic Kelch-like ECH-associated protein 1 (Keap1). Moreover, pretreatment of fucoxanthin reduced Fyn phosphorylation via protein kinase B (Akt)-mediated inhibition of glycogen synthase kinase-3β (GSK-3β), which increased the nuclear localization of Nrf2, suggesting that the compound enhanced Nrf2 expression by the activation of upstream kinase as well as the dissociation of the Nrf2-Keap1 complex. Further validation with a specific phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 demonstrated that the fucoxanthin-mediated Nrf2 antioxidant defense system was directly associated with the Akt/GSK-3β/Fyn signaling pathway. In silico simulation revealed that the oxygen groups of fucoxanthin participated in potent interactions with target markers in the Nrf2 signaling pathway, which may affect the biological activity of target markers. Taken together, the present results demonstrated that the preventive role of fucoxanthin on Aβ-stimulated oxidative injury and apoptosis via Akt/GSK-3β/Fyn signaling pathway. This study would provide a useful approach for potential intervention for AD prevention.

Granular corneal dystrophy type 2 (GCD2) is an autosomal dominant disease affecting vision. Phototherapeutic keratectomy (PTK) is advantageous in removing vision-threatening corneal opacities and postponing keratoplasty; however, it potentially disturbs accurate intraocular lens (IOL) power calculation in cataract surgery. The myopic/hyperopic Haigis-L method with or without the central island has been reported; nevertheless, an optimal method has not yet been established. To compare the predictive accuracy of post-PTK IOL power calculations in GCD2, the retrospective data of thirty eyes from July 2017 to December 2020 were analyzed. All GCD2-affected eyes underwent post-PTK standard cataract surgery using the WaveLight EX500 platform (Alcon Laboratories, Inc., Fort Worth, TX) under a single surgeon. The mean prediction error (MPE) and absolute error (MAE) with the myopic/hyperopic Haigis-L and other formulas (Barrett Universal II, Barrett True-K, Haigis, SRK/T) by standard keratometry (K) and total kera-tometry (TK), where possible, were analyzed. Barrett Universal II and SRK/T were significantly superior to the myopic/hyperopic Haigis-L regarding the MPE and MAE. TK was not significantly superior to K in the same formula. In conclusion, this study suggests that the biometries and formulas, especially Barrett Universal II and SRK/T, are potentially useful in IOL power calculation in GCD2 after PTK.

One of the pathophysiologies of post-stroke spasticity (PSS) is the imbalance of the reticulospinal tract (RST) caused by injury to the corticoreticular pathway (CRP) after stroke. We investigated the relationship between injuries of the CRP and PSS using MR diffusion tensor imaging (DTI). The subjects were divided into spasticity and control groups. We measured the ipsilesional fractional anisotropy (iFA) and contralesional fractional anisotropy (cFA) values on the reticular formation (RF) of the CRP were on the DTI images. We carried out a retrospective analysis of 70 patients with ischemic stroke. The cFA values of CRP in the spasticity group were lower than those in the control group (p = 0.04). In the sub-ROI analysis of CRP, the iFA values of pontine RF were lower than the cFA values in both groups (p &lt, 0.05). The cFA values of medullary RF in the spasticity group were lower than the iFA values within groups, and also lower than the cFA values in the control group (p &lt, 0.05). This results showed the CRP injury and that imbalance of RST caused by CRP injury was associated with PSS. DTI analysis of CRP could provide imaging evidence for the pathophysiology of PSS.

Quantification of cellular nanoparticles (NPs) is one of the most important steps in studying NP–cell interactions. Here, a simple method for the estimation of cell-associated silver (Ag) NPs in lung cancer cells (A549) is proposed based on their side scattering (SSC) intensities measured by flow cytometry (FCM). To estimate cellular Ag NPs associated with A549 cells over a broad range of experimental conditions, we measured the normalized SSC intensities (nSSC) of A549 cells treated with Ag NPs with five different core sizes (i.e., 40–200 nm, positively charged) under various exposure conditions that reflect different situations of agglomeration, diffusion, and sedimentation in cell culture media, such as upright and inverted configurations with different media heights. Then, we correlated these nSSC values with the numbers of cellular Ag NPs determined by inductively coupled plasma mass spectrometry (ICPMS) as a well-established cross-validation method. The different core sizes of Ag NPs and the various exposure conditions tested in this study confirmed that the FCM-SSC intensities are highly correlated with their core sizes as well as the amount of cellular Ag NPs over a linear range up to ~80,000 Ag NPs/cell and ~23 nSSC, which is significantly broader than those of previous studies.

Perirenal adipose tissue, one of the fat masses surrounding the kidneys, can be obtained from healthy donors during a kidney transplant. Perirenal adipose tissue has only ever been known as a connective tissue to protect the kidneys and renal blood vessels from external physical stimulation. Yet, recently, as adipose tissue has begun to be considered an endocrine organ, and perirenal adipose tissue is now regarded to have a direct effect on metabolic diseases. The characteristics of perirenal adipose tissue from a healthy donor are that: (1) There are a large number of brown adipose cells (70–80% of the total), (2) Most of the brown adipose cells are inactive in the resting cell cycle, (3) Activating factors are constant low-temperature exposure, hormones, metastasis factors, and environmental factors, (4) Anatomically, a large number of brown adipose cells are distributed close to the adrenal glands, (5) Beige cells, produced by converting white adipocytes to brown-like adipocytes, are highly active, (6) Activated cells secrete BATokines, and (7) Energy consumption efficiency is high. Despite these advantages, all of the perirenal adipose tissue from a healthy donor is incinerated as medical waste. With a view to its use, this review discusses the brown adipocytes and beige cells in perirenal adipose tissue from a healthy donor, and proposes opportunities for their clinical application.

ACEnano is an EU-funded project which aims at developing, optimising and validating methods for the detection and characterisation of nanomaterials (NMs) in increasingly complex matrices to improve confidence in the results and support their use in regulation. Within this project, several interlaboratory comparisons (ILCs) for the determination of particle size and concentration have been organised to benchmark existing analytical methods. In this paper the results of a number of these ILCs for the characterisation of NMs are presented and discussed. The results of the analyses of pristine well-defined particles such as 60 nm Au NMs in a simple aqueous suspension showed that laboratories are well capable of determining the sizes of these particles. The analysis of particles in complex matrices or formulations such as consumer products resulted in larger variations in particle sizes within technologies and clear differences in capability between techniques. Sunscreen lotion sample analysis by laboratories using spICP-MS and TEM/SEM identified and confirmed the TiO2 particles as being nanoscale and compliant with the EU definition of an NM for regulatory purposes. In a toothpaste sample orthogonal results by PTA, spICP-MS and TEM/SEM agreed and stated the TiO2 particles as not fitting the EU definition of an NM. In general, from the results of these ILCs we conclude that laboratories are well capable of determining particle sizes of NM, even in fairly complex formulations., Molecules, 26 (17), ISSN:1420-3049

This study examined the effects of workplace flexibility at deluxe hotels on work engagement, satisfaction, and commitment, to determine the moderating effect of generational characteristics (Generation X, Y, and Z). A total of 277 deluxe hotel employees in South Korea participated in the research. The results confirmed the positive effects of workplace flexibility on the engagement and satisfaction of deluxe hotel employees, second, employees’ work engagement had a positive effect on their satisfaction, third, employees’ satisfaction had a positive impact on employees’ commitment, and fourth, the influence of workplace flexibility on engagement did not differ by generation. However, Generation Z showed the largest increase in employee engagement resulting from work flexibility. This result signifies that, when compared to other generations, Generation Z places great importance on workplace flexibility. This study suggests that deluxe hotels should create flexible policies and organizational climates to increase employees’ work engagement, satisfaction, and commitment. The paper also discusses limitations and future research directions.

Due to miscommunication a number of potential co-authors were not listed in the original publication [...]

In recent years, research on the application of microdroplets in the fields of biotechnology and chemistry has made remarkable progress, but the technology for the stable generation of single-micrometer-scale microdroplets has not yet been established. In this paper, we developed an efficient and stable single-micrometer-scale droplet generation device based on the fragmentation of droplet tails, called “tail thread mode”, that appears under moderate flow conditions. This method can efficiently encapsulate microbeads that mimic cells and chemical products in passively generated single-micrometer-scale microdroplets. The device has a simple 2D structure, a T-junction is used for droplet generation, and in the downstream, multi-branch channels are designed for droplet deformation into the tail. Several 1–2 µm droplets were successfully produced by the tail’s fragmentation, this continuous splitting was induced by the branch channels. We examined a wide range of experimental conditions and found the optimal flow rate condition can be reduced to one-tenth compared to the conventional tip-streaming method. A mold was fabricated by simple soft lithography, and a polydimethylsiloxane (PDMS) device was fabricated using the mold. Based on the 15 patterns of experimental conditions and the results, the key factors for the generation of microdroplets in this device were examined. In the most efficient condition, 61.1% of the total droplets generated were smaller than 2 μm.

Aims: This study evaluated the relationship between pulse pressure (PP) and periodontal disease in Korean adults with or without hypertension (classified as HTN and non-HTN, respectively). Methods: Data on 3496 adults (≥20 years) were obtained from the Korean National Health and Nutrition Examination Survey (2015). We classified those with HTN as SBP ≥ 140 mmHg, DBP ≥ 90 mmHg, or current use of anti-hypertensive medications. Results: There were a few key findings: when logistic regression analysis was applied for periodontal disease (community periodontal index score ≥ 3), the odds ratios (OR) were significantly higher in the high PP (PP > 60 mmHg) than in the normal PP (PP ≤ 60 mmHg) in the HTN group (OR, 2.131; 95% confidence interval (CI), 1.579–2.876). However, periodontal disease was not associated with high PP in the non-HTN group and was not significant (OR, 0.866; 95% CI, 0.494–1.518). Conclusions: In Korean adults, periodontal disease was positively associated with PP in the HTN group but not in the non-HTN group.

This study was aimed at establishing whether loneliness among hotel employees in the workplace affects their psychological and emotional experiences by empirically investigating their perceptions of negative situations. A self-administered questionnaire was distributed to 300 hotel employees, after which confirmatory factor analysis was conducted to reassess the reliability and validity of the measured questionnaire items. A model of workplace loneliness, psychological detachment, and emotional exhaustion was developed and examined through structural equation modeling. The results showed that the hotel employees experienced workplace loneliness and expressed a desire to be psychologically detached from their jobs for recovery. Workplace loneliness also contributed to emotional exhaustion. Theoretical and practical implications, as well as limitations and future research directions, are discussed.

BACE1 is the rate-limiting enzyme involved in the production and deposition of &beta, amyloid (A&beta, ). Since neurotoxic A&beta, plays a critical role in Alzheimer&rsquo, s disease (AD) pathogenesis, BACE1 has emerged as a key target for preventing AD. In the present study, the potential of sulforaphane, an isothiocyanate found in cruciferous vegetables, as a BACE1 inhibitor has been investigated. Sulforaphane exhibited six times more potent activity against BACE1 compared to well-known positive controls including resveratrol and quercetin. Sulforaphane presented selective and non-competitive BACE1 inhibitory activity with low off-target inhibition of BACE2 and other aspartic and serine proteases. In addition, sulforaphane presented negative binding energy, suggesting that the compound had a high affinity for BACE1. It interacted with locations other than the active binding sites of BACE1 through van der Waals forces. Overall, sulforaphane appeared to be a promising candidate with potent and selective BACE1 inhibitory properties that play an important role in AD prevention.

In the field of speaker verification, probabilistic linear discriminant analysis (PLDA) is the dominant method for back-end scoring. To estimate the PLDA model, the between-class covariance and within-class precision matrices must be estimated from samples. However, the empirical covariance/precision estimated from samples has estimation errors due to the limited number of samples available. In this paper, we propose a method to improve the conventional PLDA by estimating the PLDA model using the regularized within-class precision matrix. We use graphical least absolute shrinking and selection operator (GLASSO) for the regularization. The GLASSO regularization decreases the estimation errors in the empirical precision matrix by making the precision matrix sparse, which corresponds to the reflection of the conditional independence structure. The experimental results on text-dependent speaker verification reveal that the proposed method reduce the relative equal error rate by up to 23% compared with the conventional PLDA.

The development of computation technology and artificial intelligence (AI) field brings about AI to be applied to various system. In addition, the research on hardware-based AI processors leads to the minimization of AI devices. By adapting the AI device to the edge of internet of things (IoT), the system can perform AI operation promptly on the edge and reduce the workload of the system core. As the edge is influenced by the characteristics of the embedded system, implementing hardware which operates with low power in restricted resources on a processor is necessary. In this paper, we propose the intellino, a processor for embedded artificial intelligence. Intellino ensures low power operation based on optimized AI algorithms and reduces the workload of the system core through the hardware implementation of a neural network. In addition, intellino&rsquo, s dedicated protocol helps the embedded system to enhance the performance. We measure intellino performance, achieving over 95% accuracy, and verify our proposal with an field programmable gate array (FPGA) prototyping.

With the aim of providing insights to scholars, administrators, and managers on how an employee&rsquo, s romantic involvement influences job engagement and performance, this study examined workplace romance as a psychological mechanism for determining job performance. A total of 224 deluxe hotel employees in South Korea participated in the research. The results indicate that workplace romance significantly affects employees&rsquo, job engagement and performance. Employees who sustain a favorable and positive relationship with others in their organization eventually exhibit increased work effectiveness, which then exerts a constructive effect on hotel services and performance. Moreover, workplace romance experience can significantly improve the effect of workplace romance on job engagement. The paper also discusses limitations and future research directions.

The purpose of this study is to investigate how foodservice employees&rsquo, perceptions of their leader&rsquo, s integrity affect their work engagement and organizational citizenship behaviors, with the aim of moderating empirical evidence of generational differences. This study was administered to 218 foodservice employees using a self-administered questionnaire. The validity and reliability of the measured items were reviewed using a confirmatory factor analysis (CFA), and they were verified using structural equation modeling (SEM). The study results showed that leader integrity had a significant positive effect on employees&rsquo, work engagement, and organizational citizenship behaviors, while employee engagement induced by leader integrity increased organizational citizenship behaviors (OCBs). Also, the results found that the effects of leader integrity on OCBs were stronger for Generation Y workers than for Generation X workers. Limitations and future research directions are also discussed.

The purpose of this study was to determine if social undermining as perceived by frontline employees significantly affects their emotional exhaustion and procrastination behavior and to clarify the moderating role of positive psychological capital. A total of 310 deluxe hotel employees in South Korea participated in this study by completing a self-administered questionnaire. The study results showed that social undermining perceived by deluxe hotel employees positively influenced their emotional exhaustion. In addition, when emotional exhaustion became severe, employees’ procrastination behavior, which harmed their organizations, increased. Additionally, the findings suggest a mediating effect, thereby indicating that employees’ procrastination behaviors may increase when they experience emotional exhaustion resulting from social undermining. When employees perform their jobs with a positive attitude in a work situation, the negative influence of social undermining and emotional exhaustion may be partially offset. Limitations and future research directions are also discussed.

This paper presents a method for utilizing three-dimensional microfluidic channels fully to realize multiple functions in a single device. The final device structure was achieved by combining three independent modules that consisted of horizontal and vertical channels. The device allowed for the one-step generation of water-in-oil-in-water droplets without the need for partial treatment of the polydimethylsiloxane channel surface using separate modules for generating water-in-oil droplets on the horizontal plane and oil-in-water droplets on the vertical plane. The second vertically structured module provided an efficient flow for the generation of highly wettable liquid droplets, and tuning of the first horizontally structured module enabled different modes of inner-core encapsulation within the oil shell. The successful integration of the vertical and horizontal channels for core-shell droplet generation and the chemical synthesis of a metal complex within the droplets were evaluated. The proposed approach of integrating independent modules will expand and enhance the functions of microfluidic platforms.

We analyzed whether a firm’s engagement in socially responsible activities, as measured by environmental, social, and corporate governance (ESG) scores, influences their tendency to avoid tax in the Korean financial market. We found a negative relationship between Korean firms’ ESG scores and tax avoidance in terms of book-tax income difference during the sample period between 2011 and 2017. This result implies that firms with good CSR performance would tend not to manipulate taxable profits, which is in line with corporate culture theory. More interestingly, this trend has become more apparent for chaebol-affiliated firms, a special type of Korean conglomerate, than non-chaebol firms.

The proteolytic processing of amyloid precursor protein (APP) by β-secretase (BACE1) and γ-secretase releases amyloid-β peptide (Aβ), which deposits in amyloid plaques and contributes to the initial causative events of Alzheimer’s disease (AD). In the present study, the regulatory mechanism of APP processing of three phlorotannins was elucidated in Swedish mutant APP overexpressed N2a (SweAPP N2a) cells. Among the tested compounds, dieckol exhibited the highest inhibitory effect on both intra- and extracellular Aβ accumulation. In addition, dieckol regulated the APP processing enzymes, such as α-secretase (ADAM10), β-secretase, and γ-secretase, presenilin-1 (PS1), and their proteolytic products, sAPPα and sAPPβ, implying that the compound acts on both the amyloidogenic and non-amyloidogenic pathways. In addition, dieckol increased the phosphorylation of protein kinase B (Akt) at Ser473 and GSK-3β at Ser9, suggesting dieckol induced the activation of Akt, which phosphorylated GSK-3β. The specific phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 triggered GSK-3β activation and Aβ expression. In addition, co-treatment with LY294002 noticeably blocked the effect of dieckol on Aβ production, demonstrating that dieckol promoted the PI3K/Akt signaling pathway, which in turn inactivated GSK-3β, resulting in the reduction in Aβ levels.

This study aims to examine the effect of workplace loneliness on work engagement and organizational commitment and the moderating role of social relationships between an employee and his or her superior and coworkers in such mechanisms. Workplace loneliness decreased employees&rsquo, engagement with their jobs and, as such, decreased engagement had a positive relationship with organizational commitment. Also, the negative influence of workplace loneliness on work engagement was found to be moderated by coworker exchange, and employees&rsquo, maintenance of positive social exchange relationships with their coworkers was verified to be a major factor for relieving the negative influence of workplace loneliness.

We aimed to analyse the CT examinations of the previous screening round (CTprev) in NLST participants with incidence lung cancer and evaluate the value of DL-CAD in detection of missed lung cancers. Thoracic radiologists reviewed CTprev in participants with incidence lung cancer, and a DL-CAD analysed CTprev according to NLST criteria and the lung CT screening reporting &amp, data system (Lung-RADS) classification. We calculated patient-wise and lesion-wise sensitivities of the DL-CAD in detection of missed lung cancers. As per the NLST criteria, 88% (100/113) of CTprev were positive and 74 of them had missed lung cancers. The DL-CAD reported 98% (98/100) of the positive screens as positive and detected 95% (70/74) of the missed lung cancers. As per the Lung-RADS classification, 82% (93/113) of CTprev were positive and 60 of them had missed lung cancers. The DL-CAD reported 97% (90/93) of the positive screens as positive and detected 98% (59/60) of the missed lung cancers. The DL-CAD made false positive calls in 10.3% (27/263) of controls, with 0.16 false positive nodules per scan (41/263). In conclusion, the majority of CTprev in participants with incidence lung cancers had missed lung cancers, and the DL-CAD detected them with high sensitivity and a limited false positive rate.

Recently, chemical operations with microfluidic devices, especially droplet-based operations, have attracted considerable attention because they can provide an isolated small-volume reaction field. However, analysis of these operations has been limited mostly to aqueous-phase reactions in water droplets due to device material restrictions. In this study, we have successfully demonstrated droplet formation of five common organic solvents frequently used in chemical synthesis by using a simple silicon/glass-based microfluidic device. When an immiscible liquid with surfactant was used as the continuous phase, the organic solvent formed droplets similar to water-in-oil droplets in the device. In contrast to conventional microfluidic devices composed of resins, which are susceptible to swelling in organic solvents, the developed microfluidic device did not undergo swelling owing to the high chemical resistance of the constituent materials. Therefore, the device has potential applications for various chemical reactions involving organic solvents. Furthermore, this droplet generation device enabled control of droplet size by adjusting the liquid flow rate. The droplet generation method proposed in this work will contribute to the study of organic reactions in microdroplets and will be useful for evaluating scaling effects in various chemical reactions.

Amyloid beta (A&beta, ) peptide, one of the most important pathogenic traits of Alzheimer&rsquo, s disease (AD), invokes a cascade of oxidative damage and eventually leads to neuronal death. In the present study, baicalein, wogonin, and oroxylin A, main active flavones in Scutellaria baicalensis, were evaluated for their neuroprotective effects against A&beta, 25&ndash, 35-stimulated damage. All tested compounds decreased A&beta, 35-induced ROS generation and cell cycle arrest. In particular, baicalein exhibited the strongest antioxidant activity. In addition, these compounds suppressed apoptosis by attenuating mitochondrial dysfunction such as loss of membrane potential, Ca2+ accumulation and Bax/Bcl-2 ratio. Furthermore, all tested flavones inhibited the expression of iNOS and COX-2, which resulted in suppressing inflammatory cytokines including TNF-&alpha, NO, and PGE2. Noticeably, all compounds exhibited the anti-inflammatory effects through downregulating NF-&kappa, B/MAPK pathway. Especially, oroxylin A was effective against both p65 and I&kappa, B&alpha, while wogonin and baicalein were suppressed phospho-p65 and phospho-I&kappa, respectively. Taken together, baicalein, wogonin, and oroxylin A can effectively relieve A&beta, 35-stimulated neuronal apoptosis and inflammation in PC12 cells via downregulating NF-&kappa, B/MAPK signaling pathway.