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Disinfectants containing percarbonate and tetraacetylethylenediamine (TAED) has been developed as an effective and relatively safe disinfectant to destroy viruses and bacteria in animals and humans, however it is known that most disinfectants can cause danger to living organisms including humans. In the current study, acute toxicity of the disinfectant composed of percarbonate and TAED was assessed by measuring behavioral responses as well as lethal concentrations of aquatic organisms such as medaka and zebrafish when they were exposed to it. First, the breeding water properties were determined by measuring dissolved oxygen (DO) and pH changes over time up to 96 h in acute toxicity tests using the medaka, and the lethal concentration 50% (LC50, 88.39 ppm) was calculated using the lethality rate of the fish. This experiment was conducted in compliance with traditional OECD guidelines. Second, the assessment of behavioral responses (locomotive activity and swimming speed) with the zebrafish were assessed by the image analysis to capture the images per second for three hours, and the collected data were processed using image analysis to calculate the locomotive activity and swimming speed. Finally, the LC50 (135.76 ppm) of the disinfectant to the fish was also measured after three hours. Overall, the data revealed that LC50 of the disinfectant may be affected by the pH of the water exposed to the disinfectant, not by the DO in the water. In addition, the results from the image analysis indicated that the behavioral responses of the fish can further assess the acute toxicity of the disinfectant at concentrations below the LC50 and there was a relationship (RThe online version of this article (doi: 10.1007/s12257-021-0419-0) contains supplementary material, which is available to authorized users.

Recent advances in drug carrier design in the field of photodynamic therapy (PDT) have stimulated the development of numerous sophisticated drug delivery carriers. We developed novel biodegradable and biocompatible nanogels as PDT carriers. The nanogels were synthesized by ATRP technique using inverse miniemulsion and their biodegradability was determined in the presence of glutathione. The model photosensitizer (PS) was encapsulated in the biodegradable nanogels by simple mixing and sonication. The cellular uptake of the PS-loaded nanogels and the cytotoxicity of the nanogels before and after laser irradiation were determined using HeLa cells. The results showed that the Ce6-nanogel complex was well internalized into the tumor cells, and the Ce6-loaded nanogels did not influence on cellular viability of the cells before light irradiation. Under light exposure, however, the Ce6-nanogel complex-treated HeLa cells revealed strong photoactivity. These nanogels may enhance therapeutic efficacy of PSs without any complex chemical modifications with PSs.

The purpose of the study was to determine the effects of dual administration of recombinant human platelet derived growth factor-BB (rhPDGF-BB) and recombinant human bone morphogenetic protein-2 (rhBMP-2) on proliferation and osteogenic differentiation of human mesenchymal stem cells (hMSCs). Either rhPDGF-BB or rhBMP-2 or a combination of the two factors was administered into hMSCs. Proliferation and osteogenic differentiation were determined by measuring DNA concentration, alkaline phosphatase (ALP) activity and mineralization (von Kossa staining) at days 7, 14 and 21. The data revealed that the administration of rhPDGF-BB (days 1-7) followed by rhBMP-2 (days 7-21) resulted in a significant increase of ALP activity and extracellular mineral deposition of hMSCs as compared to that of either factor alone or concurrent administration of the two factors. In addition, rhPDGF-BB treatment at days 1-7 significantly increased proliferation of hMSCs without decreasing osteogenic differentiation. The results underscored the importance of a coordinated, temporal sequence of rhPDGF-BB and rhBMP-2 administration to modulate hMSC osteogenic differentiation. The study was a compelling advancement towards producing a therapy exploiting temporal, dual administration of physiological doses of rhPDGF-BB and rhBMP-2.

Background Unlike bone tissue, articular cartilage regeneration has not been very successful and has many challenges ahead. We have previously developed injectable hydrogels using photopolymerizable chitosan (MeGC) that supported growth of chondrocytes. In this study, we demonstrate a biofunctional hydrogel for specific use in cartilage regeneration by conjugating transforming growth factor-β1 (TGF-β1), a well-documented chondrogenic factor, to MeGC hydrogels impregnating type II collagen (Col II), one of the major cartilaginous extracellular matrix (ECM) components. Results TGF-β1 was delivered from MeGC hydrogels in a controlled manner with reduced burst release by chemically conjugating the protein to MeGC. The hydrogel system did not compromise viability of encapsulated human synovium-derived mesenchymal stem cells (hSMSCs). Col II impregnation and TGF-β1 delivery significantly enhanced cellular aggregation and deposition of cartilaginous ECM by the encapsulated cells, compared with pure MeGC hydrogels. Conclusions This study demonstrates successful engineering of a biofunctional hydrogel with a specific microenvironment tailored to promote chondrogenesis. This hydrogel system can provide promising efficacious therapeutics in the treatment of cartilage defects. Electronic supplementary material The online version of this article (doi:10.1186/1754-1611-9-1) contains supplementary material, which is available to authorized users.

ZSM-5 type zeolites were synthesized by the hydrothermal treatment of the reaction mixture of silica sol, aluminum nitrate, sodium hydroxide, and TPABr at the temperature range of 150–180 °C in the autoclave. The shape of the ZSM-5 zeolite calcined at 450 °C was spherical or polyhedral and its crystalline size was 0.5–3 μm. The synthetic ZSM-5 was found to be highly hydrophobic and active for CO2 adsorption. ZSM-5 zeolite composite membranes supported with porous α-alumina tubes have been synthesized by dip coating or pressurized coating of the reaction sol-mixture followed by hydrothermal treatment. The permeation mechanism of CO2 through ZSM-5 membranes was a surface diffusion and the membranes prepared by the pressurized-coating hydrothermal treatment showed a fairly high CO2/N2 separation factor of 9.0 and a permeability of 10−8–10−7 mol/m2 ·s·Pa at room temperature.