New multifunctional materials containing additives derived from natural resources as powdered rosemary ethanolic extract were obtained by melt mixing and processed in good conditions without degradation and loss of additives. Incorporation of powdered rosemary ethanolic extract (R) into poly(lactic acid) (PLA) improved elongation at break, rheological properties, antibacterial and antioxidant activities, in addition to the biocompatibility. The good accordance between results of the chemiluminescence method and radical scavenging activity determination by chemical method evidenced the increased thermoxidative stability of the PLA biocomposites with respect to neat PLA, with R acting as an antioxidant. PLA/R biocomposites also showed low permeability to gases and migration rates of the bioactive compounds and could be considered as high-performance materials for food packaging. In vitro biocompatibility based on the determination of surface properties demonstrated a good hydrophilicity, better spreading and division of fibroblasts, and increased platelet cohesion. The implantation of PLA/R pellets, was proven to possess a good in vivo biocompatibility, and resulted in similar changes in blood parameters and biochemical responses with the control group, suggesting that these PLA-based materials demonstrate very desirable properties as potential biomaterials, useful in human medicine for tissue engineering, wound management, orthopedic devices, scaffolds, drug delivery systems, etc. Therefore, PLA/R-based materials show promising properties for applications both in food packaging and as bioactive biomaterials.

No abstract

The purpose of the present study is to develop new multifunctional environmentally friendly materials having applications both in medical and food packaging fields. New poly(lactic acid) (PLA)-based multifunctional materials containing additives derived from natural resources like chitosan (CS) and rosemary extract (R) were obtained by melt mixing. Each of the selected components has its own specific properties such as: PLA is a biodegradable thermoplastic aliphatic polyester derived from renewable biomass, heat-resistant, with mechanical properties close to those of polystyrene and polyethylene terephthalate, and CS offers good antimicrobial activity and biological functions, while R significantly improves antioxidative action necessary in all applications. A synergy of their combination, an optimum choice of their ratio, and processing parameters led to high performance antimicrobial/antioxidant/biocompatible/environmentally degradable materials. The polyethylene glycol (PEG)-plasticized PLA/chitosan/powdered rosemary extract biocomposites of various compositions were characterized in respect to their mechanical and rheological properties, structure by spectroscopy, antioxidant and antimicrobial activities, and in vitro and in vivo biocompatibility. Scanning electron microscopy images evidence the morphology features added by rosemary powder presence in polymeric materials. Incorporation of additives improved elongation at break, antibacterial and antioxidant activity and also biocompatibility. Migration of bioactive components into D1 simulant is slower for PEG-plasticized PLA containing 6 wt % chitosan and 0.5 wt % rosemary extract (PLA/PEG/6CS/0.5 R) biocomposite and it occurred by a diffusion-controlled mechanism. The biocomposites show high hydrophilicity and good in vitro and in vivo biocompatibility. No hematological, biochemical and immunological modifications are induced by subcutaneous implantation of biocomposites. All characteristics of the PEG-plasticized PLA-based biocomposites recommend them as valuable materials for biomedical implants, and as well as for the design of innovative drug delivery systems. Also, the developed biocomposites could be a potential nature-derived active packaging with controlled release of antimicrobial/antioxidant compounds.

No abstract

No abstract

No abstract

Burns have become an important public health problem in the last two decades, with just over a quarter of a million deaths annually. Major burns are accompanied by a strong inflammatory response, which will most often lead to systemic response inflammatory syndrome, followed by sepsis and finally induce multiple organ failure. The main mechanism involved in wound healing after burns is the inflammatory process, characterized by the recruitment of myeloid and T cells and by the involvement of numerous cytokines, chemokines, complement fractions, as well as various growth factors. Inflammasomes, protein-based cytosolic complexes, activated during metabolic stress or infection, play a role in modulating and improving the defense capacity of the innate immune system. Nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome has been studied predominantly and several hypotheses have been issued. Restoring the balance between the pro-inflammatory response and the anti-inflammatory activity is the key element to effective therapy in burns. Severe burns require nutritional support and pharmacotherapy not only for burn area but for different pathological complications of burn injury. In-depth research is required to find new ways to modulate the defense capacity, to prevent the complications of abnormal immune response and to treat burn injuries efficiently. Contents 1. Introduction 2. Burns and host immune response 3. The involvement of inflammasomes in burn and host immune response 4. Burns and the therapy 5. Conclusions

No abstract