Hyaluronic-Based Antibacterial Hydrogel Coating for Implantable Biomaterials in Orthopedics and Trauma: From Basic Research to Clinical Applications

Bacterial colonization of implanted biomaterials remains one of the most challenging complications in orthopedics and trauma surgery, with extremely high social and economic costs. Antibacterial coating of implants has been advocated by many experts as a possible solution to reduce the burden of implant-related infection and several different solutions have been proposed in the last decades. However, while most of the investigated technologies have shown their efficacy in vitro and/or in vivo, only few were able to reach the market, due to clinical, industrial, economic and regulatory issues. Hyaluronic acid composites have been previously shown to possess antifouling capabilities and have been used in various clinical settings to reduce bacterial adhesion and mitigate biofilm-related infections. Recently, a fast-resorbable, hyaluronic-based hydrogel coating was developed to protect implanted biomaterials in orthopedics, trauma and maxillofacial surgery. Preclinical and clinical testing did show the safety and efficacy of the device that can be intraoperatively loaded with one or more antibiotics and directly applied by the surgeon to the implant surface, at the time of surgery. Here, we review the current evidence concerning this very first antibacterial coating of implants and outline the economic impact of the possible large-scale application of this technology

Chapter Hyaluronic-Based Antibacterial Hydrogel Coating for Implantable Biomaterials in Orthopedics and Trauma: From Basic Research to Clinical Applications

Bacterial colonization of implanted biomaterials remains one of the most challenging complications in orthopedics and trauma surgery, with extremely high social and economic costs. Antibacterial coating of implants has been advocated by many experts as a possible solution to reduce the burden of implant-related infection and several different solutions have been proposed in the last decades. However, while most of the investigated technologies have shown their efficacy in vitro and/or in vivo, only few were able to reach the market, due to clinical, industrial, economic and regulatory issues. Hyaluronic acid composites have been previously shown to possess antifouling capabilities and have been used in various clinical settings to reduce bacterial adhesion and mitigate biofilm-related infections. Recently, a fast-resorbable, hyaluronic-based hydrogel coating was developed to protect implanted biomaterials in orthopedics, trauma and maxillofacial surgery. Preclinical and clinical testing did show the safety and efficacy of the device that can be intraoperatively loaded with one or more antibiotics and directly applied by the surgeon to the implant surface, at the time of surgery. Here, we review the current evidence concerning this very first antibacterial coating of implants and outline the economic impact of the possible large-scale application of this technology

Influence of Feeding Substrates on the Presence of Toxic Metals (Cd, Pb, Ni, As, Hg) in Larvae of Tenebrio molitor: Risk Assessment for Human Consumption

none8noLarvae of Tenebrio molitor L. (Coleoptera: Tenebrionidae) are particularly suitable as novel food for the human consumption; nevertheless, there are some potential safety risks linked with insect consumption. In this study we investigated the presence of Cd, Pb, Ni, As, Hg in new feeding substrates coming from solid residues generated by olive fruits processing, called olive-pomace, and their influence on the metal content in larvae of T. molitor. Morover, bioaccumulation factor and the mercury-selenium balance were evaluated. Analyses were carried out via graphite furnace atomic absorption spectrophotometry for Cd, Pb, Ni, As and Se, and via Direct Mercury Analyzer for Hg. All metal concentrations found in feeding substrates were below the legal limit of undesirable substances in animal feed (2002/32/EC). Concentrations in larvae were in the range (mg kg1 wet weight): Cd 0.008–0.016, Pb 0.063–0.079, Ni 0.03–0.63, As 0.021–0.023, Hg 0.12 103–0.49 103, and Se 0.057–0.085. Statistically significant correlation between metal content in feeding substrates and in larvae was evidenced only for Hg, which bioaccumulates. Se protects from mercury toxicity, with a Selenium Health Benefit Value (HVBSe) of > 0. Overall, our results indicate that the risk of exposure to metals from consumption of mealworm larvae is relatively low and in compliance with European Union regulations.restrictedCristina Truzzi, Silvia Illuminati, Federico Girolametti, Matteo Antonucci, Giuseppe Scarponi , Sara Ruschioni, Paola Riolo, Anna AnnibaldiTruzzi, Cristina; Illuminati, Silvia; Girolametti, Federico; Antonucci, Matteo; Scarponi, Giuseppe; Ruschioni, Sara; Riolo, Paola; Annibaldi, Ann

Larvae of Tenebrio molitor as a novel food for the future: evaluation of the chemical risk factor.

Due to the rapid increase in world population, the waste of food and resources, and notsustainable food production practices, the use of alternative food sources is currently strongly promoted. In this perspective, insects may represent a valuable alternative to main animal food sources since insects grow and reproduce easily, have a high feed conversion efficiency, and can transform low value of growing substrates into high value food resource [1]. Moreover, insects have a high nutrition potential due to an interesting amino acids composition, an adequate content of minerals, vitamins and polyunsaturated fatty acids. Tenebrio molitor L. (Coleoptera: Tenebrionidae) (yellow mealworm) is particularly efficient in converting the organic substance: it can transform diet substrate with a low nutritional value in a rich protein product, and is characterized by high nutritional value [2]. Different studies highlighted how its larvae are particularly suitable for the human consumption [2], and it is a perfect candidate for rearing with the aim of producing a novel food for the future. Nevertheless, the nutritional value of edible insects is highly variable, and the differences may also depend on their feeding substrates. Moreover, there are some potential safety risks linked with insect consumption: a study on the yellow mealworm larvae, for example, showed that the insects accumulate cadmium and lead in their bodies when they feed on organic matter in soils that contain these metals [3]. In the FoodIN project (Edible insects: new frontiers in food), new feeding substrates were used for rearing T. molitor, in order to investigate the best substrate and rearing conditions and the properties of the insect-based food (i.e. flour and other processed material) so obtained. Five feeding substrates were used for rearing mealworm larvae: 100% organic wheat flour, 100% organic wheatmeal, and organic wheatmeal/organic olive pomace with different percentages: 75/25, 50/50 and 25/75, respectively. In order to assess the chemical risks possibly associated with the insect-based food produced, the determination of Cd, Pb and Hg were carried out on fresh mealworm larvae and their feeding substrates. Cd and Pb were analyzed by Atomic Absorption Spectrophotometry, after microwave digestion of the samples, whereas mercury was determined with a Direct Mercury Analyzer (DMA-1). Preliminary result showed that, in insects, heavy metals concentrations were in the range: Cd, 0.007-0-015 mg/kg ww (wet wheight), Pb, 0.07-0.09 mg/kg ww, Hg, 0.12-0.4 μg/kg ww. Insects reared with 100% organic wheatmeal showed in general higher concentration of heavy metals than insects reared with other feeding substrates. Cd concentrations were lower in insects than in their respective substrates, whereas Pb and Hg concentrations in insects were higher than that of feeding substrates. In agreement with literature data, the results of this study evidenced that heavy metals present in feeding substrates are accumulate in the body of T. molitor. Considering that the legal limit of Cd, Pb for meat, and of Hg for fish food, are 0.05, 0.10 and 0.5 mg/kg (guideline UE n. 1881/2006) respectively, insects showed metals concentrations well below the legal limits. This study demonstrate that mealworm larvae can be considered a safe food from the point of view of Cd, Pb and Hg contamination. This study was financially supported by the Università Politecnica delle Marche, Ancona, Italy, within the project “Edible insects: new frontiers in food-FOODIN”

A multi-centric observational study on heterotopic ossification in severely brain injured patients with disorders of consciousness: preliminary data

Aims: to identify occurrence of neurogenic heterotopic ossification (NHO) in patients with prolonged disorder of consciousness (DoC) and possible risk factors. Design: Multi-center observational study. Setting: twenty-three intensive neurorehabilitation units. Subjects: two hundred and seventy-eight patients with prolonged disorder of consciousness (DoC; 150 in vegetative state and 128 in minimally conscious state) of different aetiology (vascular 125, traumatic=83; anoxic=56 brain injury and other brain aetiologies=14). Main Measures: at study entry: clinical evaluation by the Coma Recovery Scale-Revised (CRS-R), Disability Rating Scale (DRS), Early Rehabilitation Barthel Index (ERBI), Clinical Feature Scale (CFS); presence of ventilator support, spasticity, bone fractures. Within 3 months after admission: clinical evidence of NHO (i.e. limited range of motion and/or joint pain and/or local inflammation) confirmed by standard radiological and/or sonographic evaluation and presence of paroxysmal sympathetic hyperactivity (PSH). Results: Thirty-one patients (11.2%) developed NHO. Presence of abnormal ossifications was significantly higher in patients in VS than in patients in MCS and in patients with traumatic brain injury. Moreover patients with NHO showed higher DRS category and total score, higher occurrence of limb spasticity and bone fractures at study entry than patients without NHO. Patients with NHO did not differ from patients without NHO for sex, age, time post-injury, CRS-R and ERBI total scores, presence of non-invasive ventilator support at study entry and presence of PSH. Conclusions: Our findings suggest a relation between development of NHO and clinical diagnosis, functional disability status and aetiology in patients with DoC. Moreover, we identified spasticity and bone fractures as possible risk factors for occurrence of NHO in patients with severe brain injury and DoC