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Ligand-free FeSn2 alloy nanoparticles were used as T2 weighted MRI contrast agents for imaging lung tumors in vivo.

Ineffective site-specific delivery has seriously impeded the efficacy of nanoparticle-based drugs to a disease site. Here, we report the preparation of three different shapes (sphere, scroll, and oblate) to systematically evaluate the impact of the marginative delivery on the efficacy of magnetic resonance (MR) imaging-guided X-ray irradiation at a low dose of 1 Gy. In addition to the shape effect, the therapeutic efficacy is investigated for the first time to be strongly related to the structure effect that is associated with the chemical activity. The enhanced particle-vessel wall interaction of both the flat scroll and oblate following margination dynamics leads to greater accumulation in the lungs, resulting in superior performance over the sphere against lung tumor growth and suppression of lung metastasis. Furthermore, the impact of the structural discrepancy in nanoparticles on therapeutic efficacy is considered. The tetragonal oblate reveals that the feasibility of the charge-transfer process outperforms the orthorhombic scroll and cubic sphere to suppress tumors. Finally, surface area is also a crucial factor affecting the efficacy of X-ray treatments from the as-prepared particles.

Late diagnosis of lung cancer is one of the leading causes of higher mortality in lung cancer patients worldwide. Significant research attention has focused on the use of magnetic resonance imaging (MRI) based nano contrast agents to efficiently locate cancer tumors for surgical removal or disease diagnostics. Although contrast agents offer significant advantages, further clinical applications require improvements in biocompatibility, biosafety and efficacy.To address these challenges, we fabricated ultra-fine Iron Carbonate Nanoparticles (FeCOThe excellent biocompatibility and T2 weighted contrast abilities of FeCO

A deficiency of nitric oxide (NO) supply has been found to impair wound healing. The exogenous topical delivery of NO is a promising approach to enhance vasodilation and stimulate angiogenesis and collagen deposition. In this study, the CN groups on the surface of Prussian blue (PB) nanocubes were carefully reduced to −CH2–NH2 to conjugate with COOH group of hemin consisting of a Fe-porphyrin structure with strong affinity toward NO. Accordingly, the NO gas was able to coordinate to hemin-modified PB nanocubes. The hemin-modified PB carrying NO (PB-NO) can be responsible to near-infrared (NIR) light (808 nm) exposure to induce the thermo-induced liberation of NO based on the light-to-heat transformation property of PB nanocubes. The NO supply on the incisional wound sites can be readily topically dropped the colloidal solution of PB-NO for receiving NIR light irradiation. The enhanced blood flow was in a controllable manner whenever the wound sites containing PB-NO received NIR light irradiation. The prom...

Chronic exposure to ambient polycyclic aromatic hydrocarbons (PAHs) is associated with asthma, but its regulatory mechanisms remain incompletely defined. We report herein that elevated levels of urinary 1-hydroxypyrene, a biomarker of PAH exposure, were found in asthmatic subjects (n = 39) as compared to those in healthy subjects (n = 43) living in an industrial city of Taiwan, where indeno[1,2,3-cd]pyrene (IP) was found to be a prominent PAH associated with ambient PM2.5. In a mouse model, intranasal exposure of mice with varying doses of IP significantly enhanced antigen-induced allergic inflammation, including increased airway eosinophilia, Th2 cytokines, including IL-4 and IL-5, as well as antigen-specific IgE level, which was absent in dendritic cell (DC)-specific aryl hydrocarbon receptor (AhR)-null mice. Mechanistically, IP treatment significantly altered DC’s function, including increased level of pro-inflammatory IL-6 and decreased generation of anti-inflammatory IL-10. The IP’s effect was lost in DCs from mice carrying an AhR-mutant allele. Taken together, these results suggest that chronic exposure to environmental PAHs may pose a significant risk for asthma, in which IP, a prominent ambient PAH in Taiwan, was shown to enhance the severity of allergic lung inflammation in mice through, at least in part, its ability in modulating DC’s function in an AhR-dependent manner.

Chromium-doped zinc gallate, ZnGa2 O4 :Cr3+ (ZGC), is viewed as a long-lasting luminescence (LLL) phosphor that can avoid tissue autofluorescence interference for in vivo imaging detection. ZGC is a cubic spinel structure, a typical agglomerative or clustered morphology lacking a defined cubic shape, but a sphere-like feature is commonly obtained for the nanometric ZGC. The substantial challenge remains achieving a well-defined cubic feature in nanoscale. The process by which dispersed and well-defined concave cubic ZGC is obtained is described, exhibiting much stronger LLL in UV and X-ray excitation for the dispersed cubic ZGC compared with the agglomerative form that cannot be excited using X-rays with a low dose of 0.5 Gy. The cubic ZGC reveals a specific accumulation in liver and 0.5 Gy used at the end of X-ray excitation is sufficient for imaging of deep-seated hepatic tumors. The ZGC nanocubes show highly passive targeting of orthotopic hepatic tumors.

The present study aimed to establish the durability indices of cement-based composites containing supplementary cementitious materials. The influences of compressive strength, permeability, and microstructure of cement-based composites containing fly ash and silica fume were discussed. The relationship between pore structure and corrosion behavior was investigated and compared. The results demonstrate that the addition of silica fume in cement-based composites resulted in a higher compressive strength, a lower absorption, a lower critical pore size, a lower chloride diffusion coefficient, and a lower corrosion rate. The composites containing 10% silica fumes performed better in permeability than composites containing 5% silica fumes, because silica fumes can narrow down the size of large capillary pores and densify the pore structure. The addition of fly ash in composites also enhanced the compressive strength and the permeability but was not as effective as silica fume. Unhydrated fly ash grains caused a looser pore structure and reduced the permeability. The combination of fly ash and silica fume enhanced the compressive strength and the permeability and specimens containing 5% silica fume and 10% fly ash had increased more in compressive strength and decreased more in permeability than specimens containing 5% silica fume or 15% fly ash. Moreover, the corrosion rate, the chloride diffusion coefficient, and the critical pore size were suitable for evaluating the durability of cement-based composites. A regression analysis found that the probability of rebar corrosion was greater than 90%, when the corrosion rate was 11.54 μm/yr, the chloride diffusion coefficient was 0.62 × 10 −12 m 2 /s, or the critical pore size was 26.71 nm.

In this study, the pore systems of cement‐based composites were investigated using absorption, rapid chloride penetration, rapid migration, ponding, mercury intrusion porosimetry (MIP), and scanning electronic microscopy (SEM). Direct current polarization resistance and other permeability parameters were used as indices to justify the effects of fiber and silica fume addition on the permeability of cover concrete. Cement‐based composites containing 10% silica fumes were found to have higher compressive strength, lower absorption, lower coefficient of chloride ion diffusion, lower penetration of chloride ions and higher polarization resistance than those of control specimens. Composites with a combined addition of fiber and silica fume further increased polarization resistance and compressive strength. Addition of silica fumes further improves the permeability of fiber cement composites due to the positive effect from pozzolanic reaction, which produces denser and more homogeneous structures in th...

This paper is aimed at evaluating the properties and effectiveness of concretes containing recycled epoxy/glass (EG) particles, which were chopped and grounded waste copper-clad laminates or printed circuit board scrap. Recycled EG particles are divided into two portions according to their size: a substitutive material for natural fine aggregate and ultra fine filler, according to the particle size of 150 μm. The percentages of EG particles substituted for natural fine aggregate for the control mix were 10, 20, and 30 wt.% by considering suitable workability. Concrete strength can be significantly improved with EG particles due to the filling effect of ultra fine particles. However, as the substitute percentage of EG particles increases, the slump of fresh concrete drops and low workability is observed in the mixes with 30% EG particle even though superplasticizer is applied. Resistivity increases and absorption decreases as the percentage of fine EG particles substituted increases. The weight loss from sulfate immersion test reduces with the use of EG particles. Test results indicate that the proper application of EG particles would effectively modify the pore system, reduce permeability, and inhibit ions penetration in concrete. By considering the saving of land-fill disposal cost of waste epoxy and glass fiber scraps, enhancement of concrete properties, nontoxic waste leaching, and raw materials cost reduction, the effective utilization of recycled EG particles in concrete would be successfully achieved.

Background: Histamine exerts diverse effects on immune regulation through four types of histamine receptors (HRs). Among them, type 1 receptor (H1R) plays an important role in allergic inflammation. Dendritic cells (DCs), which express at least three types of HRs, are professional antigen-presenting cells controlling the development of allergic inflammation. However, the molecular mechanisms involved in H1R-mediated NF-ĸB signaling of DCs remain poorly defined. Methods: Bone-marrow (BM)-derived DCs (BM-DCs) were treated with H1R inverse agonists to interrupt basal H1R-mediated signaling. The crosstalk of H1R-mediated signaling and the NF-ĸB pathway was examined by NF-ĸB cellular activity using a luciferase reporter assay, NF-ĸB subunit analysis using Western blotting and TNF-α promoter activity using chromatin immunoprecipitation. Results: Blockage of H1R signaling by inverse agonists significantly inhibited TNF-α and IL-6 production of BM-DCs. H1R-specific agonists were able to enhance TNF-α production, but this overexpression was significantly inhibited by NF-ĸB inhibitor. The H1R inverse agonist ketotifen also suppressed cellular NF-ĸB activity, suggesting crosstalk between H1R and NF-ĸB signaling in DCs. After comprehensive analysis of NF-ĸB subunits, c-Rel protein expression was significantly down-regulated in ketotifen-treated BM-DCs, which led to inhibition of the promoter activity of TNF-α. Finally, adoptive transfer of the ketotifen-treated BM-DCs did not induce significant allergic airway inflammation compared to that of control cells in vivo. Conclusions: Our results suggest that c-Rel controls H1R-mediated proinflammatory cytokine production in DCs. This study provides a potential mechanism of H1R-mediated signaling and NF-ĸB pathway crosstalk in allergic inflammation.

An experimental program was carried out to evaluate the mechanical properties of cement-based composites. Test variables included water to cementitious ratio, dosage of silica fume and volume fraction of steel fiber. Compressive strength test, direct tensile strength test, splitting tensile strength test, abrasion resistance test and drop weight test were performed and the results were analyzed statistically. According to the results of this study, the designed direct tensile testing method was a suitable method to estimate the tensile strength of fiber cement-based composites. Addition of fibers provided better performance for the cement-based composites, while silica fume in the composites would help obtaining uniform fiber dispersion in the matrix and improve strength and the bonding between fiber and matrix resulting from extra dense calciumsilicate-hydrate gel. The combination of steel fibers and silica fume can greatly increase the mechanical properties of cement-based composites. Besides, a multiple regression analysis was conducted to correlate compressive strength, direct tensile strength, abrasion coefficient and impact number with w/cm ratio, silica fume content and steel fiber content and a fairly agreement between test data and estimated values was found.