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Increasing the efficiency of encapsulation of ingredients into spherical capsules can decrease the manufacturing costs of the capsules. Ingredients can be encapsulated with high efficiency (>99%) into nondegradable hard resin capsules prepared by polymerization of spherical droplets of trimethylolpropane trimethacrylate (TRIM) monomer placed on a superoleophobic material. Poly(methyl methacrylate) (PMMA) resin is a more versatile capsule material than poly-TRIM resin. In this study, the efficiency of encapsulation in PMMA resin capsules prepared from methyl methacrylate (MMA) monomer was investigated. To reduce the volatility of the MMA monomer, pre-polymerized MMA was used for capsule preparation. Although non-volatile α-tocopherol and doxorubicin could be encapsulated in the capsules with high efficiency by heat polymerization at 60°C for 3 h, the efficiency for volatile tetradecane was much lower (approximately 60%) because it evaporated. Furthermore, even when using pre-polymerized MMA, more than 70% of the prepolymer evaporated during polymerization. To prevent the evaporation of tetradecane and the prepolymer, ultraviolet photopolymerization was adopted because it was faster and could be conducted at a lower temperature. The photopolymerization prevented the evaporation of the prepolymer and increased the efficiency of encapsulation of tetradecane (approximately 90% efficiency). This polymerization system is effective for encapsulation of ingredients in PMMA capsules with high efficiency. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop in situ gellable hydrogels composed of periodate oxidized citrus pectin (OP) for localized anticancer drug delivery and evaluate the potential of OP to inhibit cancer metastasis. Doxorubicin (Dox) was coupled to OP by imine bonds. Adipic dihydrazide (ADH) was used for cross-linking of the Dox-OP conjugates. The Dox-OP conjugate solution gelled within 2 min after addition of ADH. The release rate of Dox from the hydrogels was controllable by an additive amount of ADH. The released Dox retained anticancer activity. OP was shown to have a potency to prevent homotypic cancer cell aggregation compared to unmodified citrus pectin, strongly suggesting that OP released from hydrogels in vivo will inhibit cancer metastasis. These results indicate that OP hydrogels have the potential to prevent progression of primary cancer by the released Dox and generation of metastatic cancer by the released OP. [ABSTRACT FROM AUTHOR]

Abstract  Reduction of the amount of pesticides applied to agricultural land is essential for environmental conservation. It can be accomplished by immobilization of the pesticides in polymer supports, which prevents their volatilization, degradation and leaching losses, and provides controlled release of the chemicals. In the present study, acetamiprid, a novel pesticide, was encapsulated in PLA-based microspheres using the solvent evaporation method via oil-in-oil (O/O) emulsion. Silicon oil and an acetonitrile solution with dissolved synthetic polymer(s) and acetamiprid were used as an outer and inner oil phases, respectively. The entrapment efficiency of the pesticide in the case of PLA microspheres decreased with increasing the concentration of the pesticide in the inner oil phase. The amount of acetamiprid released from the microspheres was less than 18 %. On the other hand, incorporation of poly(-caprolactone) (PCL) into the PLA microspheres resulted in increased amount of releasable pesticide (approximately 89 %). These results indicate that the PCL/PLA microsphere is a promising immobilization support of the acetamiprid for practical application. [ABSTRACT FROM AUTHOR]

Abstract  Microencapsulation of pesticides is a promising technique for avoiding high initial doses and multiple applications of the chemicals to agricultural land which cause environmental pollution. It is because the formulation is possible to improve the stability of the chemicals against environmental degradation and control the release rate. In the present study, polymeric microcapsules prepared by the solvent evaporation method via water-in-oil-in-water (W/O/W) emulsion were used as immobilization supports of acetamiprid, a water-soluble pesticide. The pesticide was loaded in the microcapsules by impregnating the polymeric supports with acetamiprid dissolved in an organic solvent. Increased volume ratio (ϕ) of inner aqueous phase to oil phase in the emulsion system contributed to more pores in the microcapsules and increase in the content of acetamiprid in the polymeric supports. Release rate of acetamiprid from the microcapsules could be controlled by changing ϕ. [ABSTRACT FROM AUTHOR]

Hydrogel fibers that possessed a cell-adhesive surface and were degradable via enzymatic reactions were developed for fabricating tubular constructs with smooth muscle cell (SMC) and endothelial cell (EC) layers, similar to native blood vessels, in collagen gels. The fibers were prepared by soaking hydrogel fibers prepared from a solution of sodium alginate and gelatin containing bovine ECs (BECs) in medium containing oxidized alginate (AO). BECs soaked in 8.0% (w/v) AO showed no reduction in viability within 3 h of soaking. Furthermore, mouse SMCs (MSMCs) adhered and proliferated on the AO-cross-linked hydrogels. Based on these results, we prepared AO-cross-linked hydrogel fibers containing BECs, covered their surface with MSMCs, and embedded them in collagen gels. We then degraded the fibers using alginate lyase to obtain channels in the collagen gels. Histological analysis of the released ECs using a specific fluorescent dye revealed the formation of tubular structures with layered BECs and MSMCs. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most common malignancy worldwide. Disease progression leads to its spread to other organs, such as the liver, and is associated with higher mortality rates. Early CRC detection is therefore crucial for maximizing the chances of complete cure. The measurement of serum-based tumor biomarkers has shown great potential for the detection of CRC. In this study, we investigated the feasibility of using angiopoietin-like protein 2 (ANGPTL2) as a candidate biomarker for CRC. We first investigated ANGPTL2 expression in 7 CRC cell lines, among which Colo320, NCC-CoCK-115P, Caco-2 and Colo205 exhibited comparatively high ANGPTL2 expression. The serum levels of ANGPTL2 in CRC patients (3.45±1.30 ng/ml) were higher compared with those in healthy controls (2.74±0.64 ng/ml) (P<0.05). A receiver operating characteristic analysis demonstrated that the diagnostic performance of ANGPTL2 was marginally lower compared with that of the established biomarker C-reactive protein, but higher compared with that of carbohydrate antigen 19-9. These results suggested that the simultaneous measurement of ANGPTL2, along with previously established serum biomarkers, may increase the likelihood of early detection of CRC. [ABSTRACT FROM AUTHOR]