Search

Glaucoma treatment involves reducing the intraocular pressure (IOP), which can damage the optic nerve, to a normal range. Aqueous drainage devices may be used for treatment, and a variety of devices have been proposed. However, they have a non-variable and uniform inner diameter, which makes it difficult to accommodate the IOP fluctuations that occur after glaucoma surgery. To ensure effective treatment in the early post-operative period with low IOP and the late post-operative period with high IOP, the inner diameter should be expandable over time to allow for smooth aqueous drainage. Here, we applied 3D printing technology with a tri-axial nozzle to develop an aqueous drainage tube that can expand its inner diameter. The distinct bilayer structure of the device allows it to expand its inner diameter through biodegradation, which can accommodate the IOP fluctuations that often occur after glaucoma surgery. The fabricated structure was evaluated in a series of tests, including leakage, cytotoxicity, and degradation experiments. The device did not show any leakage, was not toxic to cells, and demonstrated the expansion of the inner diameter through biodegradation. The device may provide a more effective post-operative solution for glaucoma patients by alleviating the effects of low IOP in the early post-operative period and high IOP in the late post-operative period. [ABSTRACT FROM AUTHOR]

ObjectiveHere we use a novel ELISA that is specific for full-length visfatin (PBEF/NAMPT), compare it with the existing C-terminal based assay and use it to investigate associations of visfatin with metabolic parameters.Design, patients and measurementsWe established the specificity and effectiveness of the new ELISA and evaluated the associations of full-length visfatin with clinical, anthropometric and metabolic parameters in a cross-sectional study of 129 Thai subjects, consisting of 50 outpatients with type 2 diabetes and 79 healthy volunteers.ResultsThe new ELISA accurately recovered full-length recombinant visfatin and detected visfatin secreted by primary human and rat adipocytes. We found serum full-length visfatin was significantly higher in subjects with diabetes compared to their nondiabetic peers (median 2.75 vs. 2.22 ng/ml, P = 0.0142). After adjustment for age, gender and traditional metabolic risk factors, adjusted mean visfatin remained significantly higher in the diabetes group (3.80 vs. 2.10 ng/ml, P = 0.0021). On Spearman univariate correlation analysis, visfatin was significantly associated with resistin (r = 0.30, P = 0.0011), but not with any other anthropometric or metabolic variables, including adiponectin multimers. On multiple linear regression analysis, the only covariates independently associated with visfatin were diabetes (t = 3.11, P = 0.0024) and log resistin (t = 2.68, P = 0.0086).ConclusionsCirculating visfatin is independently associated with diabetes and resistin concentration, but is not related to adiponectin multimers or other metabolic covariates. These data are suggestive of a potential role of visfatin in subclinical inflammatory states.

Supercapacitors have attracted attention as efficient energy storage systems owing to their high power density and cycling stability. The use of appropriate electrode materials is important for high-performance supercapacitors, and various carbon materials have been studied as supercapacitor electrodes. In this study, carbon nanofibers with high specific surface areas were fabricated via a simple electrospinning process. Carbon nanofibers were fabricated by adjusting the ratio of polyacrylonitrile (PAN) to bisphenol A (BPA) and evaluated as electrode materials for supercapacitors. With the addition of BPA, improved specific surface area and oxygen functional groups were observed compared with nanofibers using only PAN. Therefore, BPA3, which had the highest specific surface area, exhibited a 28% improvement in capacitance (162 F/g) compared with BPA0 fabricated using only PAN. Carbon nanofibers fabricated by adjusting the ratio of BPA to PAN are promising electrodes for supercapacitors owing to their high capacitance and stability. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) are of great importance in terms of reducing operational costs and benefiting from system durability. However, SOFCs exhibit sluggish oxygen reduction reactions (ORRs) at cathodes. To overcome this, extensive research is focused on the development of cathodes with superior ORR properties for SOFCs. In this study, a fibrous composite cathode composed of strontium‐doped samarium cobaltate (SSC) and samarium‐doped ceria (SDC) is fabricated via electrospinning. Composite fiber cathodes prepared at specific ratios exhibit ORR properties and oxygen‐ion conductivity, which are attributed to the growth of small SSC particles in the fibrous electrode and nanolattice strain of SSC at the SSC and SDC interface. As such, the enhanced cathode performance contributes to an improvement in the power‐generation characteristics of SOFCs (1.33 W cm−2 at 1073 K using 300 μm thick La(Sr)Ga(Mg)O3 electrolyte). This structural engineering of dual‐phase fiber is a promising design that promotes cathodic ORR performance. [ABSTRACT FROM AUTHOR]

Energy storage systems (ESSs) are attracting increasing attention for the development of sustainable and renewable energy technologies owing to limited fossil fuels. Supercapacitors are gaining significant interest as energy storage devices owing to their high-power density and long-term cycle stability. The use of suitable electrode materials affects the performance of supercapacitors. In this study, we fabricated a carboxyl-doped graphene nanoplatelet (CGnP) via a mechanochemical reaction. Additionally, CGnP was activated by controlling parameters such as temperature, flow rate, and maintenance period and evaluated as an electrode material for supercapacitors. The effect of the specific surface area (SSA) and functional groups of the fabricated samples on the capacitance was confirmed by controlling the activation parameters. The activated CGnP with 300 mL/min of CO2 at 1173 K for 4 h exhibited a high SSA of 1300 m2/g. The activated CGnP (180 F/g), with a high SSA, showed an increased capacitance of 46% compared to pristine CGnP (123 F/g). Additionally, activated CGnP1100 demonstrated good wettability and exhibited excellent stability with a low capacitance decrease of 6.1%, even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Energy conversion and storage systems have recently attracted significant attention owing to increasing environmental and energy problems. However, the slow kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) render their commercialization difficult. Many studies are being conducted to replace precious metal catalysts that have high activity for the ORR and OER but have scarcity and low stability. In this study, Sm0.5Sr0.5CoO3 (SSC) nanofibers were fabricated via the electrospinning of non-precious metal-based perovskite oxides to replace precious metal catalysts. In addition, the properties and electrochemical performance of SSC fibers synthesized at different calcination temperatures were evaluated. The small crystallite size, high specific surface area, abundant oxygen vacancies, and high ORR/OER activity suggest that SSC800 hollow fibers are optimal bifunctional catalysts. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are important for developing energy systems such as fuel cells and metal–air batteries. Precious metal catalysts, such as Pt and IrO2, have been considered electrochemical catalysts because of their excellent activity for the ORR and OER. However, their disadvantages, such as low durability for long-term operation and high price, necessitate the development of alternative electrochemical catalysts. Transition metal oxides with excellent electrical conductivity, high efficiency, and stability have been considered alternative electrochemical catalysts owing to their ORR and OER activities, which are similar to those of precious metal catalysts. Therefore, in this study, composite catalyst materials comprising Co3O4 and CoFe2O4 spinel oxides were synthesized via hydrothermal synthesis. The synthesized composite oxides exhibit bi-functional electrochemical catalytic activity for ORR and OER owing to the large active surface area and increased number of oxygen vacancies via the nanostrain in Co3O4 nanoparticles. [ABSTRACT FROM AUTHOR]

Retinol binding protein 4 (RBP4) is a useful biomarker in the diagnosis of type 2 diabetes since its level in the serum is higher in insulin-resistant states. Accurate measurement of the serum RBP4 levels is hampered by conventional immunologic methods, such as enzymelinked immunosorbent assay (ELISA). In this study, therefore, we have developed an aptamer-based surface plasmon resonance (SPR) biosensor that can be used to sense for RBP4 in serum samples. A single-stranded DNA (ssDNA) aptamer that showed high affinity ([K.sub.d] = 0.2 [+ or -] 0.03 [micro]M) and specificity to RBP4 was selected. This RBP4-specific aptamer was immobilized on a gold chip and used in a label-free RBP4 detection using SPR. Analysis of RBP4 in artificial serum using SPR was compared with ELISA and Western blot analysis. Our results indicated that the RBP4-specific aptamer-based SPR biosensor gave better dose-dependent responses and was more sensitive than ELISA assays. As such, this RBP4 aptamer-based SPR biosensor can be potentially used to monitor the RBP4 levels within the serum as an indicator of type 2 diabetes.

HCC (Hepatocellular carcinoma) is the most common malignant tumor; however, the molecular pathogenesis of these tumors is not well understood. Sorafenib, an approved treatment for HCC, inhibits angiogenesis and tumor cell proliferation. However, only ~30% of patients are sensitive to sorafenib and most show disease progression, indicating resistance to sorafenib. The present study used machine learning to investigate several mechanisms related to sorafenib resistance in liver cancer cells. This revealed that unphosphorylated interferon-stimulated genes (U-ISGs) were upregulated in sorafenib-resistant liver cancer cells, and the unphosphorylated ISGF3 (U-ISGF3; unphosphorylated STAT1, unphosphorylated STAT2 and IRF9) complex was increased in sorafenib-resistant liver cancer cells. Further study revealed that the knockdown of the U-ISGF3 complex downregulated U-ISGs. In addition, inhibition of the U-ISGF3 complex downregulated cell viability in sorafenib-resistant liver cancer cells. These results suggest that U-ISGF3 induced sorafenib resistance in liver cancer cells. Also, this mechanism may also be relevant to patients with sorafenib resistance. [ABSTRACT FROM AUTHOR]