The use of surgical meshes to reinforce damaged internal soft tissues has been instrumental for successful hernia surgery; a highly prevalent condition affecting yearly more than 20 million patients worldwide. Intraperitoneal adhesions between meshes and viscera are one of the most threatening complications, often implying reoperation or side effects such as chronic pain and bowel perforation.
Despite recent advances in the optimization of mesh porous structure, incorporation of anti-adherent coatings or new approaches in the mesh fixation systems, clinicians and manufacturers are still pursuing an optimal material to improve the clinical outcomes at a cost-effective ratio. Here, bacterial nanocellulose (BNC), a bio-based polymer, is evaluated as a soft tissue reinforcement material regarding mechanical properties and in vivo anti-adhesive performance. A double-layer BNC laminate proved sufficient to meet the standards of mechanical resistance for abdominal hernia reinforcement meshes. BNC-polypropylene (BNC-PP) composites incorporating a commercial mesh have also been prepared. The in vivo study of implanted BNC patches in a rabbit model demonstrated excellent anti-adherent characteristics of this natural nanofibrous polymer 21-days after implantation and the animals were asymptomatic after the surgery. BNC emerges as a novel and versatile hernioplasty biomaterial with outstanding mechanical and anti-adherent characteristics.
Bioactive materials for therapy and diagnosis
In vivo soft tissue reinforcement with bacterial nanocellulose
Irene Anton-Sales, Soledad Roig-Sanchez, Kamelia Traeger, Christine Weis, * Anna Laromaine, Pau Turon and Anna Roig *
Nanostructuring nanocarbons with IrOx yields to material coatings with large charge capacities for neural electrostimulation, and large reproducibility in time, that carbons do not exhibit. This work shows the contributions of carbon and the different nanostructures present, as well as the impact of functionalizing graphene with oxygen and nitrogen, and the effects of including conducting polymers within the hybrid materials. Different mammalian neural growth models differentiate the roles of the substrate material in absence and in presence of applied electric fields and address optimal electrodes for the future clinical applications.
Electrodeposited iridium oxide (K1.7IrO0.8 (OH)2.2 × 1.8 H2O; also called IrOx) is among the best substrates for neural growth, decreasing impedance and stimulating cell growth, when used as a connected electrode. Without direct contact, it has been proven to stimulate neurons through a bipolar mechanism related to the conducting character of the material in the presence of remote electric fields.
This paper describes the transition from the normal to inverted Marcus region in solid-state tunnel junctions consisting of self-assembled monolayers of benzotetrathiafulvalene (BTTF), and how this transition determines the performance of a molecular diode. Temperature-dependent normalized differential conductance analyses indicate the participation of the HOMO (highest occupied molecular orbital) at large negative bias, which follows typical thermally activated hopping behavior associated with the normal Marcus regime.
Four novel transition metal-carborane photosensitisers were prepared by Sonogashira cross-coupling of 1-(4-ethynylbenzyl)-2-methyl-o-carborane (A-CB) with halogenated Ru(II)- or Ir(III)-phenanthroline complexes. The resulting boron-rich complexes with one (RuCB and IrCB) or two carborane cages (RuCB2 and IrCB2) were spectroscopically characterised, and their photophysical properties investigated. RuCB displayed the most attractive photophysical properties in solution (λem 635 nm, τT 2.53 μs, and φp 20.4 %).
A multitude of microparticles and nanoparticles is developed to improve the delivery of different small drugs and large biomolecules, which are subject to several hindering biological barriers that limit their optimal biodistribution and therapeutic effects. Here, a soft, reliable, and scalable method based on compressed CO2 is reported for obtaining nanoconjugates of recombinant human epidermal growth factor and nanovesicles called quatsomes, where the latter consists of cholesterol and cetyltrimethylammonium bromide.These nanoconjugates exhibit appropriate values of the major critical quality attributes of colloidal nanomedicines, such as controlled and narrow nanoscopic particle size distribution (which play important roles in determining their stability), drug loading, drug release, drug protection, targeting ability, and bioactivity.