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1.
Small ; 20(9): e2305999, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37840400

ABSTRACT

An unprecedented correlation between the catalytic activity of a Zr-based UiO-type metal-organic framework (MOF) and its degree of interpenetration (DOI) is reported. The DOI of an MOF is hard to control owing to the high-energy penalty required to construct a partially interpenetrated structure. Surprisingly, strong interactions between building blocks (inter-ligand hydrogen bonding) facilitate the formation of partially interpenetrated structures under carefully regulated synthesis conditions. Moreover, catalytic conversion rates for cyanosilylation and Knoevenagel condensation reactions are found to be proportional to the DOI of the MOF. Among MOFs with DOIs in the 0-100% range, that with a DOI of 87% is the most catalytically active. Framework interpenetration is known to lower catalytic performance by impeding reactant diffusion. A higher effective reactant concentration due to tight inclusion in the interpenetrated region is possibly responsible for this inverted result.

2.
Article in English | MEDLINE | ID: mdl-34886067

ABSTRACT

Given that little is known about overseas travelers' responses and behaviors toward China after the outbreak of COVID-19, this study aimed to uncover risk perception factors and investigate its role in Korean travelers' avoidance/hesitation behaviors toward China as an international tourism destination in the case of the COVID-19 pandemic. To explore the relationship with risk perception, anticipated emotion and avoidance/hesitation behavior, a quantitative method along with an online survey was employed. This focus was on Korean tourists who had traveled to China at least once. Findings revealed that risk perception and negative anticipated emotion are vital facilitators of avoidance/hesitation behaviors, and that positive anticipated emotion reduces such behaviors. The efficacy of a higher-order structure of risk perception, which encompasses six dimensions, was also demonstrated. In addition, destination attachment lowered the influence of risk perception on the formation of avoidance/hesitation behaviors. Overall, our results will help tourism researchers and practitioners understand what factors drive and reduce international travelers' avoidance/hesitation behaviors toward China in the post-pandemic world. Implications for theory and practice are offered.


Subject(s)
COVID-19 , Pandemics , China , Humans , Republic of Korea , SARS-CoV-2 , Travel
3.
FASEB J ; 35(4): e21482, 2021 04.
Article in English | MEDLINE | ID: mdl-33710708

ABSTRACT

Antisense transcription occurs widely more expected than when it was first identified in bacteria in the 1980s. However, the functional relevance of antisense transcripts in transcription remains controversial. Here, we investigated the putative role of antisense transcripts in regulating their corresponding sense transcripts by analyzing changes in correlative relationships between sense-antisense pairs under tumor and normal conditions. A total of 3469 sense-antisense gene pairs (SAGPs) downloaded from BioMart mapped to a list of sense and antisense genes in RNA-seq data derived from 80 paired colorectal cancer (CRC) samples were analyzed. As a result, cancer-related genes were significantly enriched in the significantly correlated SAGPs (SCPs). Differentially expressed genes estimated between normal and tumor conditions were also significantly more enriched in SCPs than in non-SCPs. Interestingly, using differential correlation analysis, we found that tumor samples had a significantly larger density of genes with higher correlation coefficients than normal samples, as verified by various cancer transcriptomes from The Cancer Genome Atlas (TCGA). Moreover, we found that the magnitude of the correlation between SAGPs could distinguish poor prognostic CRCs from good prognostic CRCs, showing that correlation coefficients between the SAGPs of CRCs with a poor prognosis were significantly stronger than CRCs with a good prognosis. Consistent with this finding, the Cox proportion hazards model showed that the survival rates were significantly different between patients with high and low expression of genes in the SCPs. All these results strongly support the idea that antisense transcripts are important regulators of their corresponding sense transcripts.


Subject(s)
Colorectal Neoplasms/genetics , Oncogenes/genetics , RNA, Antisense/genetics , RNA, Messenger/genetics , Gene Expression Profiling/methods , Humans , Oligonucleotide Array Sequence Analysis/methods , Transcription, Genetic/genetics
4.
J Transl Med ; 18(1): 433, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33183332

ABSTRACT

BACKGROUND: Obesity is a chronic low-grade inflammatory disease that is generally characterized by enhanced inflammation in obese adipose tissue (AT). Here, we investigated alterations in gene expression between lean and obese conditions using mRNA-Seq data derived from human purified adipocytes (ACs) and preadipocytes (preACs). RESULTS: Total mRNA-seq data were generated with 27 AC and 21 preAC samples purified from human visceral AT collected during resection surgery in cancer patients, where the samples were classified into lean and obese categories by BMI > 25 kg/m2. We defined four classes of differentially expressed genes (DEGs) by comparing gene expression between (1) lean and obese ACs, (2) lean and obese preACs, (3) lean ACs and lean preACs, and 4) obese ACs and obese preACs. Based on an analysis of comparison 1, numerous canonical obesity-related genes, particularly inflammatory genes including IL-6, TNF-α and IL-1ß, i.e., the genes that are expected to be upregulated in obesity conditions, were found to be expressed at significantly lower levels in obese ACs than in lean ACs. In contrast, some inflammatory genes were found to be expressed at higher levels in obese preACs than lean preACs in the analysis of comparison 2. The analysis of comparisons 3 and 4 showed that inflammatory gene classes were expressed at higher levels in differentiated ACs than undifferentiated preACs under both lean and obese conditions; however, the degree of upregulation was significantly greater for lean than for obese conditions. We validated our observations using previously published microarray transcriptome data deposited in the GEO database (GSE80654). CONCLUSIONS: Taken together, our analyses suggest that inflammatory genes are expressed at lower levels in obese ACs than in lean ACs because lean adipogenesis involves even greater enhancement of inflammatory responses than does obese adipogenesis.


Subject(s)
Adipocytes , Adipose Tissue , Adipogenesis/genetics , Gene Expression , Humans , Obesity/genetics
5.
Article in English | MEDLINE | ID: mdl-32872267

ABSTRACT

This study investigated restaurant customers' perceived importance of key factors in accordance with dining occasions and restaurant segments. Our investigation into restaurant selection and situational factors present two types of empirical evidence regarding customers' choice of restaurant. First, menu price was customers' top priority in restaurant selections for full-service, quick-casual, and quick-service restaurants. Second, restaurant customers rated the importance level of restaurant selection criteria differently according to eating-out occasions. The importance of menu price was greatest for both quick meal/convenience and social occasion, brand reputation was the most important factor for business necessity, and word-of-mouth recommendation was greatest for celebration.


Subject(s)
Choice Behavior , Consumer Behavior , Meals , Restaurants , Commerce , Humans
6.
Biochem Genet ; 58(4): 617-630, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32347401

ABSTRACT

Tobacco smoking, a risk factor for several human diseases, can lead to alterations in DNA methylation. Smoking is a key source of cadmium exposure; however, there are limited studies examining DNA methylation alterations following smoking-related cadmium exposure. To identify such cadmium exposure-related DNA methylation, we performed genome-wide DNA methylation profiling using DNA samples from 50 smokers and 50 non-smokers. We found that a total of 136 CpG sites (including 70 unique genes) were significantly differentially methylated in smokers as compared to that in non-smokers. The CpG site cg05575921 in the AHRR gene was hypomethylated (Δ ß > - 0.2) in smokers, which was in accordance with previous studies. The rs951295 (within RNA gene LOC105370802) and cg00587941 sites were under-methylated by > 15% in smokers, whereas cg11314779 (within CELF6) and cg02126896 were over-methylated by ≥ 15%. We analyzed the association between blood cadmium concentration and DNA methylation level for 50 smokers and 50 non-smokers. DNA methylation rates of 307 CpG sites (including 207 unique genes) were significantly correlated to blood cadmium concentration (linear regression P value < 0.001). The four significant loci (cg05575921 and cg23576855 in AHRR, cg03636183 in F2RL3, and cg21566642) were under-methylated by > 10% in smokers compared to that in non-smokers. In conclusion, our study demonstrated that DNA methylation levels of rs951295, cg00587941, cg11314779, and cg02126896 sites may be new putative indicators of smoking status. Furthermore, we showed that these four loci may be differentially methylated by cadmium exposure due to smoking.


Subject(s)
Cadmium/blood , DNA Methylation/genetics , Tobacco Smoking/blood , Tobacco Smoking/genetics , Adult , Basic Helix-Loop-Helix Transcription Factors/genetics , Cotinine/urine , CpG Islands/genetics , Genetic Loci , Genome-Wide Association Study , Humans , Male , Middle Aged , Receptors, Thrombin/genetics , Repressor Proteins/genetics , Tobacco Smoking/urine
7.
IEEE Int Conf Rehabil Robot ; 2013: 6650498, 2013 Jun.
Article in English | MEDLINE | ID: mdl-24187313

ABSTRACT

The purpose of this paper is to propose a new assessment method for evaluating motor function of the patients who are suffering from physical weakness after stroke, incomplete spinal cord injury (iSCI) or other diseases. In this work, we use a robotic device to obtain the information of interaction occur between patient and robot, and use it as a measure for assessing the patients. The Intentional Movement Performance Ability (IMPA) is defined by the root mean square of the interactive torque, while the subject performs given periodic movement with the robot. IMPA is proposed to quantitatively determine the level of subject's impaired motor function. The method is indirectly tested by asking the healthy subjects to lift a barbell to disturb their motor function. The experimental result shows that the IMPA has a potential for providing a proper information of the subject's motor function level.


Subject(s)
Exercise Therapy/instrumentation , Motor Activity/physiology , Robotics/instrumentation , Task Performance and Analysis , Adult , Humans , Male , Man-Machine Systems , Spinal Cord Injuries/rehabilitation , Stroke Rehabilitation , Torque
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