The use of rigid materials to adequately support the joints and exert corrective forces that control the deformities of the bones is a key pre-requisite in prescribing custom-fit orthoses in rehabilitation treatment. Traditional orthotic materials are heavy in weight, bulky and completely unbreathable, which reduce the quality of life, comfort and satisfaction with the orthosis and result in poor patient compliance and even significant curve progression. The present study aims to explore the use of carbon fibre, fibreglass and fibreglass-carbon composites to develop an orthotic brace. Apart from the mechanical testing, the thermal discomfort properties and in-brace pressure with the use of traditional orthotic braces were also examined. Compared to traditional thermoplastic materials, the fibre composite materials have good resistance to breakage, more flexibility in bending with improved water vapour transmission, air permeability and thermal conductivity which advance orthosis use and wear comfort. An increase in the number of layers of composite materials increases the bending rigidity and also considerably augments the corrective forces. The corrective forces and/or support that control the deformity of joints or bones can therefore be adjusted by altering the number of layers of composites. The use of fibre composite materials in orthoses not only improves the prevailing problems of wear discomfort, but also facilitates the control of corrective forces, thus enhancing the quality of orthotic intervention.
A significant challenge still remains for the development of drug delivery system (DDS) using herbal medicine for clinical applications. The present study describes a novel DDS consisting of a natural antibacterial drug berberine and silk fibroin (SF) for controlled drug delivery application. Composite films were synthesized using of SF and berberine mixtures at varied ratios. The unique structural features of SF molecules were analyzed using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) during different film processing and post-processing conditions. Results revealed that water-annealed and glycerol modified method accurately controlled crystallization via modification of the secondary structure of the SF matrix and interaction with the non-crystalline domains, resulting in control of film degradation as well as drug diffusion rate. A linear relationship between crystallinity content (beta-sheet dominated silk II structure) and the release of entrapped berberine was achieved. The initial antibacterial activity of berberine retained for 4 days. The stability of the drug in SF film enhanced the intermolecular interactions between SF and berberine molecules. In conclusion, the composite materials consisting of SF and berberine have a great potential application as a DDS providing antimicrobial activities, such as antimicrobial suture and biomedical textiles.
Lead aprons are typically worn by radiographers to protect them from harmful radiation. As such, a good radiation shield must have a high Lead Equivalence to minimize the transmitted radiation dose during exposure. While most radiation shields fulfil this requirement by using matrices of lead and other substances, most aprons are uncomfortable to wear. Further, if the examination takes longer than expected, the radiographer will feel discomfort because of the heavy weight of the apron, or the smooth surface of the coated casing material. Another issue is the poor fit and design of the aprons due to the stiffness of the lead sheet. In general, the comfort characteristics of any textile material are related to air permeability, moisture management, abrasion resistance, fabric structure, thickness and weight, as well as yarn types. The objective of this study is to use standard testing methods to characterize some selected fabrics in terms of their X-ray shielding ability, physical, mechanical, and morphologic properties. The implication of this research will help for further study of this type of fabrics to improve thermal comfort of X-ray protective clothing.
In this study, we report a facile approach to develop composite nanofibrous mat for tissue engineering application. Montmorillonite (MMT) nanoparticles were first used to load an antipyretic analgesic drug, aspirin (ASP). The ASP-loaded MMT nanohybrids were mixed with polyurethane (PU) for subsequent electrospinning to form drug-loaded PU/MMT/ASP composite nanofibrous mats. Then electrospun PU/MMT/ASP nanofibers were assembled with a bilayer of polyacrylic acid (PAA) and poly(ethylene imine) (PEI) through electrostatic interaction. Silver nanoparticles have been immobilized onto nanofibrous mats by in situ complexation and chemical reduction of AgNO3 solution to form PU/MMT/ASP/Ag nanofibrous mats. The PU/MMT/ASP/Ag composite nanofibrous mats were systematically characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and mechanical testing. In vitro drug release showed that this composite nanofibrous drug delivery system can effectively mitigate the burst release of the drug and the introduction of MMT can improve the tensile stress property. Further the antibacterial properties and cytotoxicity evaluation of these mats demonstrate that the PU/MMT/ASP/Ag has a reasonable activity toward the growth inhibition of model bacterium Staphylococcus aureus, and the PU/MMT/ASP/Ag nanofibers display good cytocompatibility. In view of its sustained release profile and excellent biocompatibility, this double-loaded drug delivery system may have great prospect in tissue engineering.
In this research work, the effect of various construction parameters and structural characteristics of weft knitted spacer fabric on the compressive behavior and energy absorption capability was studied. The potential compression mechanism of the fabric was identified with support of the compression stress-strain curve, work done and efficiency at different compression stages. The results show that the compressive stress at the same compressive strain increases with the fabric density, and the stress-strain curves of spacer fabrics with different densities were all composed of initial, elastic region, plateau region and densification region. Third order polynomial regression model was used to establish the elastic deformation properties to obtain the compression results. The spacer fabrics ideal energy-absorption efficiency curves were obtained from their stress-strain curves and all findings show that stress corresponding to at the peak of the energy-absorption efficiency was closed to the densification stress of material. Advance statistical evaluation and one-way analysis of variance is used to analyze the significance of various factors such as thickness, spacer yarn diameter and surface structures on energy absorption at maximum compression load and deformation. These findings are important requirements for designing weft knitted spacer fabrics for cushioning applications in car seats, mattress, shoe insoles etc.