Government's subsidisation policy and utilisation of smoking cessation treatments: a population-based cross-sectional study in Taiwan.

OBJECTIVES: This study examined the associations between the Second-Generation Cessation Payment Scheme (SCPS) and the use of smoking cessation treatments. Furthermore, these associations were compared between light and heavy smokers in Taiwan. DESIGN: This study had a cross-sectional design. SETTING: Data were obtained from the Taiwan Adult Smoking Behaviour Surveillance System 2010-2011 and 2013-2014; data for each year consisted of a nationally representative sample of adults aged 18 years and older. PARTICIPANTS: Current smokers who had either quit or made a serious attempt to quit smoking were selected for the analysis. PRIMARY OUTCOME MEASURE: The primary outcome measure was the use of a smoking cessation clinic or pharmacy in a twice daily to quit smoking. RESULTS: According to multivariate analysis, the SCPS was positively associated with the combined use of a smoking cessation clinic and a pharmacy (OR=3.947; 95% CI: 1.359 to 11.463) when individual-level predictors (gender, age, education level, marital status, monthly household income, daily cigarette consumption, smoking status and self-reported health) were controlled. Heavy smokers showed a significant increase in the sole use of a pharmacy (OR=1.676; 95% CI: 1.094 to 2.569) and combined use of a smoking cessation clinic and pharmacy (OR=8.984; 95% CI: 1.914 to 42.173) after the SCPS was introduced. In addition, when related factors were controlled, the use of smoking cessation services was more frequent among heavy smokers than light smokers, including any treatment (OR=1.594; 95% CI: 1.308 to 1.942), a smoking cessation clinic (OR=1.539; 95% CI: 1.232 to 1.922), a pharmacy (OR=1.632; 95% CI: 1.157 to 2.302) and the combination of a smoking cessation clinic and pharmacy (OR=4.608; 95% CI: 1.331 to 15.949) . CONCLUSIONS: The SCPS subsidisation policy increased the use of smoking cessation treatments, particularly among heavy smokers.

Mechanotransduction of matrix stiffness in regulation of focal adhesion size and number: reciprocal regulation of caveolin-1 and ß1 integrin.

Focal adhesion (FA) assembly, mediated by integrin activation, responds to matrix stiffness; however, the underlying mechanisms are unclear. Here, we showed that ß1 integrin and caveolin-1 (Cav1) levels were decreased with declining matrix stiffness. Soft matrix selectively downregulated ß1 integrin by endocytosis and subsequent lysosomal degradation. Disruption of lipid rafts with methyl-ß-cyclodextrin or nystatin, or knockdown of Cav1 by siRNA decreased cell spreading, FA assembly, and ß1 integrin protein levels in cells cultured on stiff matrix. Overexpression of Cav1, particularly the phospho-mimetic mutant Cav1-Y14D, averted soft matrix-induced decreases in ß1 integrin protein levels, cell spreading, and FA assembly in NMuMG cells. Interestingly, overexpression of an auto-clustering ß1 integrin hindered soft matrix-induced reduction of Cav1 and cell spreading, which suggests a reciprocal regulation between ß1 integrin and Cav1. Finally, co-expression of this auto-clustering ß1 integrin and Cav1-Y14D synergistically enhanced cell spreading, and FA assembly in HEK293T cells cultured on either stiff ( > G Pa) or soft (0.2 kPa) matrices. Collectively, these results suggest that matrix stiffness governs the expression of ß1 integrin and Cav1, which reciprocally control each other, and subsequently determine FA assembly and turnover.

Matrix-Stiffness-Regulated Inverse Expression of Krüppel-Like Factor 5 and Krüppel-Like Factor 4 in the Pathogenesis of Renal Fibrosis.

The proliferation of mouse proximal tubular epithelial cells in ex vivo culture depends on matrix stiffness. Combined analysis of the microarray and experimental data revealed that Krüppel-like factor (Klf)5 was the most up-regulated transcription factor accompanied by the down-regulation of Klf4 when cells were on stiff matrix. These changes were reversed by soft matrix via extracellular signal-regulated kinase (ERK) inactivation. Knockdown of Klf5 or forced expression of Klf4 inhibited stiff matrix-induced cell spreading and proliferation, suggesting that Klf5/Klf4 act as positive and negative regulators, respectively. Moreover, stiff matrix-activated ERK increased the protein level and nuclear translocation of mechanosensitive Yes-associated protein 1 (YAP1), which is reported to prevent Klf5 degradation. Finally, in vivo model of unilateral ureteral obstruction revealed that matrix stiffness-regulated Klf5/Klf4 is related to the pathogenesis of renal fibrosis. In the dilated tubules of obstructed kidney, ERK/YAP1/Klf5/cyclin D1 axis was up-regulated and Klf4 was down-regulated. Inhibition of collagen crosslinking by lysyl oxidase inhibitor alleviated unilateral ureteral obstruction-induced tubular dilatation and proliferation, preserved Klf4, and suppressed the ERK/YAP1/Klf5/cyclin D1 axis. This study unravels a novel mechanism how matrix stiffness regulates cellular proliferation and highlights the importance of matrix stiffness-modulated Klf5/Klf4 in the regulation of renal physiologic functions and fibrosis progression.

Regulation of proximal tubular cell differentiation and proliferation in primary culture by matrix stiffness and ECM components.

To explore whether matrix stiffness affects cell differentiation, proliferation, and transforming growth factor (TGF)-ß1-induced epithelial-mesenchymal transition (EMT) in primary cultures of mouse proximal tubular epithelial cells (mPTECs), we used a soft matrix made from monomeric collagen type I-coated polyacrylamide gel or matrigel (MG). Both kinds of soft matrix benefited primary mPTECs to retain tubular-like morphology with differentiation and growth arrest and to evade TGF-ß1-induced EMT. However, the potent effect of MG on mPTEC differentiation was suppressed by glutaraldehyde-induced cross-linking and subsequently stiffening MG or by an increasing ratio of collagen in the soft mixed gel. Culture media supplemented with MG also helped mPTECs to retain tubular-like morphology and a differentiated phenotype on stiff culture dishes as soft MG did. We further found that the protein level and activity of ERK were scaled with the matrix stiffness. U-0126, a MEK inhibitor, abolished the stiff matrix-induced dedifferentiation and proliferation. These data suggest that the ERK signaling pathway plays a vital role in matrix stiffness-regulated cell growth and differentiation. Taken together, both compliant property and specific MG signals from the matrix are required for the regulation of epithelial differentiation and proliferation. This study provides a basic understanding of how physical and chemical cues derived from the extracellular matrix regulate the physiological function of proximal tubules and the pathological development of renal fibrosis.

Detection of real sample DNA at a cadmium sulfide--chitosan/gelatin modified electrode.

Cadmium sulfide (CdS) was combined with chitosan (Chi) and gelatin (Gel) to prepare a CdS-Chi/Gel modified electrode. Chi exhibits a large positive charge density and was to provide a uniform of CdS surface. Gel exhibits high mechanical strength and low toxicity toward mammalian cells, and is non-antigenic biopolymer. CdS-Chi exhibits a lower contact angle than that of bare CdS, indicating that the hydrophilicity of the sample surface had increased. Electrochemical impedance spectroscopy (EIS) was used to determine diffusion coefficients and to characterize the electron transfer kinetics during the redox reactions. The surface morphologies of CdS-Chi and Gel were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Differential pulse voltammetry (DPV) was used to detect the analytes. DPV not only increased the linear range of the electrocatalytic current, but also lowered the overpotential for oxidation interference in the measurements. The CdS electrode exhibited a enhanced electrocatalytic activity toward the analytes evaluated in this study. The presence of Gel enhanced the loading and stability of the electrode. The fabricated electrode was successfully used for the simultaneous electrochemical oxidation of guanine (G) and adenine (A).

Enhancement of renal epithelial cell functions through microfluidic-based coculture with adipose-derived stem cells.

Current hemodialysis has functional limitations and is insufficient for renal transplantation. The bioartificial tubule device has been developed to contribute to metabolic functions by implanting renal epithelial cells into hollow tubes and showed a higher survival rate in acute kidney injury patients. In healthy kidney, epithelial cells are surrounded by various types of cells that interact with extracellular matrices, which are primarily composed of laminin and collagen. The current study developed a microfluidic coculture platform to enhance epithelial cell function in bioartificial microenvironments with multiple microfluidic channels that are microfabricated by polydimethylsiloxane. Collagen gel (CG) encapsulated with adipose-derived stem cells (CG-ASC) was injected into a central microfluidic channel for three-dimensional (3D) culture. The resuspended Madin-Darby canine kidney (MDCK) cells were injected into nascent channels and formed an epithelial monolayer. In comparison to coculture different cells using the commercial transwell system, the current coculture device allowed living cell monitoring of both the MDCK epithelial monolayer and CG-ASC in a 3D microenvironment. By coculture with CG-ASC, the cell height was increased with columnar shapes in MDCK. Promotion of cilia formation and functional expression of the ion transport protein in MDCK were also observed in the cocultured microfluidic device. When applying fluid flow, the intracellular protein dynamics can be monitored in the current platform by using the time-lapse confocal microscopy and transfection of GFP-tubulin plasmid in MDCK. Thus, this microfluidic coculture device provides the renal epithelial cells with both morphological and functional improvements that may avail to develop bioartificial renal chips.

[Inhibition of remineralization by EDTA-soluble phosphate protein in dentin].

OBJECTIVE: To investigate the effect of removing EDTA-soluble phosphate protein in dentin on the later remineralization for the purpose of better understanding of mechanism of dentin phosphate proteins on dentin mineralization. METHODS: To remove soluble phosphate protein by EDTA dissolution, then the remineralization rate was monitored by a constant composition crystal growth technique. The results were compared with those from the normal dentin and the dentin partially demineralized by acetic acid. RESULTS: Faster remineralization rates were found with dentin demineralized by EDTA (0.5 and 2 h) compared with normal dentin powder, while a slower rate was found with dentin demineralized by acetic acid. The increase of remineralization rate by removing phosphate protein from dentin was 100% more at 200 min after the start of the reaction. CONCLUSION: EDTA-soluble phosphate protein in dentin has a great potential to inhibit remineralization.