Topological Optimisation Structure Design for Personalisation of Hydrogel Controlled Drug Delivery System.

Personalised controlled drug delivery systems (CDDSs) can adjust drug concentration levels according to patient needs, which has enormous research prospects in precision medicine. In this study, the topological optimisation method was utilised in the structural design of a hydrogel CDDS to achieve a parameter-based adjustment of the drug average concentration in the hydrogel. A polyacrylamide/sodium alginate dual-network hydrogel was selected as a drug carrier, and tetracycline hydrochloride was used as a model drug. The topological optimisation model of the hydrogel CDDS was developed. The effects of the mesh size, target concentration, and volume factor on the optimised results were investigated. Hydrogel flow channel structures were obtained, which satisfied the different target concentrations. To verify the rationality of the optimisation model, in vitro drug release experiments were carried out. The results show that the hydrogel CDDS can control drug release within 7 days, and the drug release tends to follow zero-order release behaviour. The adjustable average concentration of tetracycline hydrochloride in hydrogel CDDS is recommended in the range of 20.79 to 31.04 mol/m3. This novel method provides a reference for personalised structure design of CDDS in the context of precision medicine.

Effect of alumina shapes on dielectric properties of UV-cured epoxy acrylic composite with alumina.

Polymer-based composites with the advantages of ceramics and polymers exhibit high dielectric constant, good processing properties and low dielectric loss. The composites with a varied content of irregular alumina (i-Al2O3) filler were prepared by UV-cured epoxy acrylic (EA). Spherical alumina (s-Al2O3) was used as a filler to further investigate the effect of alumina (Al2O3) shapes on dielectric properties of composites in the frequency range of 50 Hz-1 MHz. Fourier transform infrared spectroscopy proved that the UV-cured epoxy acrylic/alumina (Al2O3/EA) composites were successfully fabricated. Scanning electron microscopy demonstrated that i-Al2O3 particles have superior homodispersion in the matrix. Through testing, for all samples, with the addition of Al2O3, the relative permittivity of composites increased as expected, and the dielectric loss decreased accordingly. These data show that the incorporation of i-Al2O3 particles presents better properties when compared with s-Al2O3/EA, which indicates that i-Al2O3 particles have more influence on the dielectric properties of the composites than those of s-Al2O3 particles. According to Weibull distribution, the characteristic breakdown strength of the Al2O3/EA composites was obtained and the results suggested that the composites of i-Al2O3/EA exhibited better breakdown performance.

Protective effects of selenium against zearalenone-induced apoptosis in chicken spleen lymphocyte via an endoplasmic reticulum stress signaling pathway.

Selenium (Se), an antioxidant agent, provides significant protection from reactive oxygen species (ROS)-induced cell damage in vivo and in vitro. However, it is unclear whether Se can protect against zearalenone (ZEN)-induced apoptosis in chicken spleen lymphocyte. In this study, we investigated the underlying mechanism of the apoptosis induced by ZEN in chicken spleen lymphocyte and further evaluated the protective mechanism of Se on ZEN-induced apoptosis. The results show that ZEN induced an increase in ROS generation and lipid peroxidation, and a decrease in levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione (GSH). The results of apoptosis morphologically from acridine orange/ethidium bromide (AO/EB) fluorescent staining and flow cytometry analysis show apparent apoptosis in the ZEN-treated group, and was confirmed by the upregulation of caspase-3, -12 and downregulation of Bcl-2. Meanwhile, ZEN activated the endoplasmic reticulum (ER) stress by upregulating ER stress-related molecular sensors (GRP78, ATF6, ATF4, IRE). However, co-treatment with Se effectively blocked ROS generation, improved antioxdative capacity, and reversed apoptosis and ER stress-related genes and protein expression. Taken together, these data suggest that oxidative stress and ER stress play a vital role in ZEN-induced apoptosis, and Se had a significant preventive effect on ZEN-induced apoptosis in chicken spleen lymphocyte via ameliorating the ER stress signaling pathway.

Development and evaluation of a VP1-ELISA for detection of antibodies to duck hepatitis type 1 virus.

The VP1-encoding gene of the duck hepatitis type 1 virus (DHV-1) HP-1 strain was cloned and expressed in Escherichiacoli. The open reading frame (ORF) of VP1 comprised 714 bp and encoded 238 amino acids, with a predicated molecular mass of 26.5 kDa. The expressed VP1 fusion protein in E. coli was detected by Western blotting with duck anti-DHV-1 polyclonal serum. A VP1-ELISA using the expressed VP1 protein as a coating antigen for the detection of antibodies to DHV-1 in ducks was developed. In comparison with the virus neutralization test, the specificity and sensitivity of the VP1-ELISA was 92.5% and 96.7%. Comparative analysis between Western blots and the VP1-ELISA showed that the concordance between the two methods was 86%. The VP1-ELISA did not react with the anti-sera to other duck viral pathogens, implying that this protein is specific for the recognition of duck anti-DHV-1 antibodies. Taken together, the VP1-ELISA is a highly sensitive and specific test that could be used for screening for DHV-1 infection and monitoring antibody titres against DHV-1.