Understanding Continuance Intention to Use Mobile Fitness Services: The Roles of Technological Characteristics and Network Effects

Mobile fitness platforms are effective in promoting healthy behaviors but these platforms generally suffer from low retention rates. It is necessary to study how to retain users of mobile fitness platforms. Based on customer value theory and Socio-technical approach, this study proposed a theoretical model to study the factors that affect users’ continuance intention to use mobile fitness platforms from a holistic perspective. A total of 320 valid questionnaires were collected to verify the model. The results indicate that utilitarian value and hedonic value are positively related to continuance intention. Social ties are negatively related to continuance intention. Meanwhile, it is found that technological characteristics have significant positive influences on utilitarian value, hedonic value and social ties. Network effects have significant positive influences on hedonic value and social ties. These findings extend our understanding of users’ continued usage of mobile fitness platforms and provide practical implications for mobile fitness service providers

No association between Id2 gene methylation and tetralogy of Fallot: a case-control study in China children

The aim of this case-control study was to investigate the correlation between the methylation levels of inhibitor of DNA binding 2 (Id2) gene and the incidence of tetralogy of Fallot (TOF) in children. The study included 31 TOF and 32 healthy control children. The methylation status of the Id2 gene was determined with time-of-flight mass spectrometry. Peripheral blood indices were detected, and their correlations with Id2 gene methylation were analyzed. Methylation analysis showed that there was no significant difference in the Id2 gene methylation level between the control and TOF groups (P > 0.05). After controlling the factors of gender, age, height and body weight, the analysis showed that there was no correlation between the methylation levels at each Id2 site and the red blood cells (RBC), hemoglobin (HGB) or hematocrit (HCT) (P > 0.05). However, the methylation levels at the CpG-16 and CpG-18.19 sites of the Id2 gene were negatively correlated with the mean corpuscular hemoglobin (MCH) (r = −0.337, P = 0.009; r = −0.392, P = 0.002) and mean corpuscular hemoglobin concentration (MCHC) (r = −0.363, P = 0.005; r = −0.286, P = 0.028), respectively. Our results suggest that the Id2 methylation might not be associated with the incidence of TOF. These results might contribute to the understanding of the etiology and mechanism of TOF in clinic

IFNα-Expressing Amniotic Fluid-Derived Mesenchymal Stem Cells Migrate to and Suppress HeLa Cell-Derived Tumors in a Mouse Model

Background. Immunotherapy for cervical cancer with type I interferon (IFN) is limited because of the cytotoxicity that accompanies the high doses that are administered. In this study, we investigated the utilization of amniotic fluid-derived mesenchymal stem cells (AF-MSCs) as a means for delivering IFNα to local tumor sites for the suppression of cervical cancer in a mouse model using HeLa cell xenografts. Methods. The tumor tropism ability of AF-MSCs and AF-MSCs genetically modified to overexpress IFNα (IFNα-AF-MSCs) was examined through Transwell in vitro and through fluorescent images and immunohistochemistry in a mouse model. Tumor size and tumor apoptosis were observed to evaluate the efficacy of the targeting therapy. Mechanistically, tumor cell apoptosis was detected by cytometry and TUNEL, and oncogenic proteins c-Myc, p53, and Bcl-2 as well as microvessel density were detected by immunohistochemistry. Results. In this model, intravenously injected AF-MSCs selectively migrated to the tumor sites, participated in tumor construction, and promoted tumor growth. After being genetically modified to overexpress IFNα, the IFNα-AF-MSCs maintained their tumor tropism but could significantly suppress tumor growth. The restrictive efficacy of IFNα-AF-MSCs was associated with the suppression of angiogenesis, inhibition of tumor cell proliferation, and induction of apoptosis in tumor cells. Neither AF-MSCs nor IFNα-AF-MSCs trigger tumor formation. Conclusions. IFNα-AF-MSC-based therapy is feasible and shows potential for treating cervical cancer, suggesting that AF-MSCs may be promising vehicles for delivering targeted anticancer therapy

An Enzyme-Responsive Controlled Release System of Mesoporous Silica Coated with Konjac Oligosaccharide

A simple and green method to fabricate an ingenious enzyme-responsive drug controlled release system was presented. Mesoporous silica material (mSiO₂) 100 nm in size was used as the host, and Konjac oligosaccharide (KOGC) was employed to seal the nanopores of mSiO₂ to inhibit the drug release. Rhodamine B was used as the model cargo to reveal the release behavior of the system. The KOGC-modified mSiO₂ (mSiO₂@KOGC) retains the drug until it reaches the colonic environment where bacteria secrete enzymes (β-mannanase) can degrade KOGC and make drug release. The amount of KOGC and enzyme can be used to adjust the release performance. And all the release behaviors fit the two-step Higuchi model, which predominate by KOGC degradation and mesoporous structure, respectively. With well bioactivity and selectivity, the system has potential application as an oral medicine carrier for treating intestinal disease

An outbreak of acute respiratory disease in China caused by human adenovirus type B55 in a physical training facility

Objectives: To investigate the cause of an acute respiratory tract infection (ARTI) outbreak. Methods: Thirty-eight clinical samples were collected from 19 patients in an ARTI outbreak that occurred in a physical training facility in January 2013; patient demographic information was also collected. In addition, 60 influenza virus-negative samples from febrile respiratory patients were collected from the same community at the same time to determine whether these were the same infections. Multiplex PCR (multi-PCR) was used to detect the possible pathogen in these samples. All human adenovirus (HAdV)-positive samples were inoculated onto Hep-2 cells for isolation. HAdV isolates were typed by hexon gene, fiber gene, and whole genome sequencing using primers designed in-house and compared to different type/serotype HAdVs downloaded from GenBank. Phylogenetic analysis was used to determine the type of the HAdV. Results: Of the 38 samples, 34 from 17 cases were HAdV-positive; two of them were co-infected, one with respiratory syncytial virus A and the other with human rhinovirus. The hexon gene open reading frame (ORF; 2841 nucleotides (nt)) and fiber gene ORF (978 nt) were obtained from four HAdV strains (TJ-2013-92, TJ-2013-94, TJ-2013-100, TJ-2013-122) from three upper respiratory infection cases and one pneumonia case. They were all completely identical. One HAdV isolate, TJ-2013-90, was selected for whole genome sequencing; 34 238 nt were obtained. Phylogenetic analysis showed the whole genome of TJ-2013-90 to be clustered together with HAdV-B55/HAdV-B11a. Three of 60 influenza virus-negative specimens were HAdV-positive, but hexon and fiber gene analysis showed that they were grouped in different branches to the HAdV isolates from this outbreak. Conclusions: The cause of this ARTI outbreak was HAdV-B55. This was another outbreak caused by this re-emerging virus. Continuous surveillance of respiratory adenovirus is necessary for disease control

MiR-222-3p promotes the proliferation, migration and invasion of papillary thyroid carcinoma cells through targeting SLC4A4

Objective. An increasing number of studies indicate that miR-222-3p is upregulated in various cancers and can regulate tumor progression. This study aimed to explore the regulatory mechanism of miR-222- 3p in papillary thyroid carcinoma (PTC). Methods. TCGA database was used to dig differentially expressed miRNAs and mRNAs in PTC tissue. Relevant references were searched to determine target miRNA. StarBase, TargetScan and miRDB were applied to predict mRNAs that had binding sites with the target miRNA. Then, the mRNAs were intersected with differentially downregulated mRNAs in TCGA to determine the target mRNA. qRT-PCR was exerted to evaluate gene expression of miR-222-3p and SLC4A4 in PTC. Western blot was performed out to evaluate the protein expression of SLC4A4 in PTC cells. CCK-8, wound healing assay and cell invasion assay were undertaken to observe the proliferative, migratory, and invasive abilities of PTC cells. Dual-luciferase assay was employed to test the binding relationship between miR222-3p and SLC4A4. Results. MiR-222-3p was highly expressed in PTC while SLC4A4 was lowly expressed. Moreover, miR222-3p was able to promote the proliferation, invasion, and migration of PTC cells. SLC4A4 was able to reverse these promotive effects of miR-222-3p. Conclusion. MiR-222-3p can promote the proliferation, migration and invasion of PTC cells through targeting SLC4A4. MiR-222-3p is expected to be a molecular therapeutic target for PTC patients