Preparation of Gel Forming Polymer-Based Sprays for First Aid Care of Skin Injuries.

Currently, there are several types of materials for the treatment of wounds, burns, and other topical injuries available on the market. The most used are gauzes and compresses due to their fluid absorption capacity; however, these materials adhere to the surface of the lesions, which can lead to further bleeding and tissue damage upon removal. In the present study, the development of a polymer-based gel that can be applied as a spray provides a new vision in injury protection, respecting the requirements of safety, ease, and quickness of both applicability and removal. The following polymeric sprays were developed to further obtain gels based on different polymers: hydroxypropyl cellulose (HPC), polyvinyl pyrrolidone (PVP) and hydroxypropyl methylcellulose (HPMC) using polyethylene glycol (PEG) as a plasticizer. The developed sprays revealed suitable properties for use in topical injuries. A protective film was obtained when sprayed on a surface through a casting mechanism. The obtained films adhered to the surface of biological tissue (pig muscle), turning into a gel when the exudate was absorbed, and proved to be washable with saline solution and contribute to the clotting process. Moreover, biocompatibility results showed that all materials were biocompatible, as cell viability was over 90% for all the materials.

Photocrosslinkable Nanofibrous Asymmetric Membrane Designed for Wound Dressing.

Recently, the biomedical scientists who are working in the skin regeneration area have proposed asymmetric membranes as ideal wound dressings, since they are able to reproduce both layers of skin and improve the healing process as well as make it less painful. Herein, an electrospinning technique was used to produce new asymmetric membranes. The protective layer was composed of a blending solution between polycaprolactone and polylactic acid, whereas the underlying layer was comprised of methacrylated gelatin and chitosan. The chemical/physical properties, the in vitro hemo- and biocompatibility of the nanofibrous membranes were evaluated. The results obtained reveal that the produced membranes exhibited a wettability able to provide a moist environment at wound site. Moreover, the membranes' hemocompatibility and fibroblast cell adhesion, spreading and proliferation at the surface of the membranes were also noticed in the in vitro assays. Such results highlight the suitability of these asymmetric membranes for wound dressing applications.

Coaxial electrospun PCL/Gelatin-MA fibers as scaffolds for vascular tissue engineering.

Coaxial electrospinning is a technique that allows the production of nanofibers with a core-shell structure. Such fibers present several advantages as materials for the preparation of scaffolds, namely due to the possibility of combining a core with the desired mechanical properties with a shell prepared from biocompatible materials that will establish proper interactions with the host. Herein, core-shell fibrous meshes, composed of a polycaprolactone (PCL) core and a functionalized gelatin shell, were prepared by coaxial electrospinning and then photocrosslinked under UV light aiming to be used in vascular tissue regeneration. The suitability of the meshes for the pretended biomedical application was evaluated by assessing their chemical/physical properties as well as their haemo and biocompatibility in vitro. The obtained results revealed that meshes' shell prepared with a higher content of gelatin showed fibers with diameters presenting a unimodal distribution and a mean value of 600nm. Moreover, those fibers with higher content of gelatin also displayed lower water contact angles, and therefore higher hydrophilicities. Such features are crucial for the good biologic performance displayed by these meshes, when in contact with blood and with Normal Human Dermal Fibroblasts cells.

A Mapping Study on Mobile Games for Patients of Chronic Diseases.

There is a growing interest of using technologies to propose solutions for healthcare issues. One of such issues is the incidence of chronic diseases, which are responsible for a considerable proportion of worldwide mortality. It is possible to prevent the development of such diseases using tools and methods that instruct the population. To achieve this, mobile games provide a powerful environment for teaching different subjects to user, without them actively knowing that they are learning new concepts. Despite the growing interest of using mobile games in healthcare, more specifically by patients with chronic diseases, in the best of our knowledge there are no studies that address the current research being published in the area. To close this gap, we carried out a systematic mapping study to synthesize an overview of the area. Five databases were searched and more than 1200 studies were analyzed and filtered. Among them, 17 met the the inclusion and exclusion criteria defined in this work. The results show that there is still room for research in this area, since the studies focus on a younger audience rather than proposing solutions for all ages. Furthermore, the number of chronic conditions being addressed is still small, obesity and diabetes are prevalent. Besides, the full capacity of game features that foster learning through games are not being employed, the majority of games proposed by the articles encompass less than half of these features.

Production and characterization of polycaprolactone- hyaluronic acid/chitosan- zein electrospun bilayer nanofibrous membrane for tissue regeneration.

A bilayered electrospun membrane was produced in this study, using the electrospinning technique, to be applied as a skin substitute. The upper layer of the membrane was comprised by hyaluronic acid and polycaprolactone in order to provide mechanical support and also to act as a physical barrier against external threats. Chitosan and zein were used to produce the bottom layer that was loaded with salicylic acid, in order to confer anti-inflammatory and antimicrobial activity to this layer. The physicochemical properties of the membranes were determined and the obtained results showed that the produced electrospun membrane display an ideal porosity, appropriate mechanical properties, controlled water loss and a suitable salicylic acid release profile. In addition, membranes did not exhibit any toxic effects for human fibroblast cells, since cells were able to adhere, spread and proliferate. Furthermore, no biofilm formation was noticed on membranes' surface along the experiments. In conclusion, the gathered data reveal that this electrospun membrane has suitable properties to be used as a wound dressing.

3D Printed scaffolds with bactericidal activity aimed for bone tissue regeneration.

Nowadays, the incidence of bone disorders has steeply ascended and it is expected to double in the next decade, especially due to the ageing of the worldwide population. Bone defects and fractures lead to reduced patient's quality of life. Autografts, allografts and xenografts have been used to overcome different types of bone injuries, although limited availability, immune rejection or implant failure demand the development of new bone replacements. Moreover, the bacterial colonization of bone substitutes is the main cause of implant rejection. To vanquish these drawbacks, researchers from tissue engineering area are currently using computer-aided design models or medical data to produce 3D scaffolds by Rapid Prototyping (RP). Herein, Tricalcium phosphate (TCP)/Sodium Alginate (SA) scaffolds were produced using RP and subsequently functionalized with silver nanoparticles (AgNPs) through two different incorporation methods. The obtained results revealed that the composite scaffolds produced by direct incorporation of AgNPs are the most suitable for being used in bone tissue regeneration since they present appropriate mechanical properties, biocompatibility and bactericidal activity.