Nanostructured polymeric coatings based on chitosan and dopamine-modified hyaluronic acid for biomedical applications

In a marine environment, specific proteins are secreted by mussels and used as a bioglue to stick to a surface. These mussel proteins present an unusual amino acid 3,4-dihydroxyphenylalanine (known as DOPA). The outstanding adhesive properties of these materials in the sea harsh conditions have been attributed to the presence of the catechol groups present in DOPA. Inspired by the structure and composition of these adhesive proteins, we used dopamine-modified hyaluronic acid (HA-DN) prepared by carbodiimide chemistry to form thin and surface-adherent dopamine films. This conjugate was characterized by distinct techniques, such as nuclear magnetic resonance and ultraviolet spectrophotometry. Multilayer films were developed based on chitosan and HA-DN to form polymeric coatings using the layer-by-layer methodology. The nanostructured films formation was monitored by quartz crystal microbalance. The film surface was characterized by atomic force microscopy and scanning electron microscopy. Water contact angle measurements were also conducted. The adhesion properties were analyzed showing that the nanostructured films with dopamine promote an improved adhesion. In vitro tests showed an enhanced cell adhesion, proliferation and viability for the biomimetic films with catechol groups, demonstrating their potential to be used in distinct biomedical applications.The authors want to acknowledge the COST Action TD0906 - Biological adhesives: from biology to biomimetics. The authors also acknowledge the financial support from the Fundacao para a Ciencia e para a Tecnologia through the Ph.D. grants with the references SFRH/BD/73119/2010 and SFRH/BD/69529/2010. G. G. Ferrer acknowledges the support of the Spanish Ministry of Science and Innovation for the mobility grant JC2008-00135. G. Botelho acknowledges the NMR portuguese network (PTNMR, Bruker Avance III 400-Univ. Minho)

Spray-assisted layer-by-layer assembly on hyaluronic acid scaffolds for skin tissue engineering

Tissue engineering approaches for the development of a single epidermal-dermal scaffold to treat full-thickness skin defects have been limited by difficulties in the fabrication of a bilayer scaffold combining the specific properties of the epidermis and the dermis. Here we present an innovative approach to developing a scaffold that holds promise for skin tissue engineering. We utilize the spray-assisted layer-by-layer assembly technique to deposit a polyelectrolyte multilayer film composed of hyaluronic acid and poly-L-lysine (the epidermal component) on a porous hyaluronic acid scaffold (the dermal component), in a rapid and controlled manner. The multilayer film promotes cell adhesion, contributing to regeneration of the epidermal barrier functions of skin. While human keratinocytes attached and proliferated on the coated porous scaffolds, they did not invade the porous dermal component, thus leaving room for seeding of relevant fibroblast cell types in this scaffold. This scaffold therefore holds promise for co-culture of different cells, which may be useful for treatment of full-thickness skin defects as well as other tissue engineering applications.Contract grant sponsor: Portuguese Foundation for Science and Technology; contract grant number: BD/39396/2007Contract grant sponsors: MIT-Portugal Program; National Science Foundation Graduate Research Fellowshi

Fatty acids, minerals, phenolics and vitamins in the seeds of <i>Inocarpus fagifer</i>, a Pacific Island underutilized legume

Recently, Pacific nations have faced to alarming increase in prevalence of noncommunicable diseases connected with consumption of non-traditional processed food. It is believed that re-introduction of native diet may mitigate these negative trends. One of the traditional staple food of Pacific region are seeds of underutilized leguminous tree Inocarpus fagifer. Nevertheless, information on their chemical composition and nutritional properties are missing. Therefore we decided to analyze this crop for the presence of fatty acids, minerals, phenolics and vitamins. Performed analyses revealed a slightly predominating portion of unsaturated (e.g. 18:2 n-6; 18:1 n-9 and 18:3α n-3) over saturated (e.g. C18 and C16) fatty acids. Considering minerals, the substantial concentrations of copper, magnesium, manganese, potassium and zinc (19.32; 1823.21; 8.44; 23308.41 and 77.99 mg kg-1 of dry matter respectively) were recorded. Ferulic and coumaric acids were the most abundant phenolics (3.23 and 1.48 mg kg-1 of dry matter respectively), whereas flavonoids, isoflavonoids and coumestrol were also present. Regarding vitamins, niacin and riboflavin were found in respective concentrations 131.80 and 4.47 mg kg-1 of dry matter. Our findings suggest I. fagifer seeds as a prospective food source of several health-beneficial constituents which might contribute to the well-being of Pacific islanders.   The online version of this article (doi: 10.5073/JABFQ.2016.089.034) contains a supplementary file

Odzysk energetyczny odpadów komunalnych

The article summarizes possibilities of energy recovery from municipal and other waste. It describes the history of incineration and energy recovery from municipal waste in Czechoslovakia and then in the Czech Republic. The attention is paid to the three currently operated plants for energy recovery from municipal waste in the Czech Republic (ZEVO Malešice, SAKO Brno, TERMIZO Liberec, and ZEVO Chotíkov). The following are the characteristics of the planned plants for energy recovery from municipal waste in the Czech Republic. All these plants operate essentially based on grate boilers with fl ue gas treatment at the highest technical level. The article also lists other technologies, which can be used for energy recovery from municipal waste - these are gasifi cation and pyrolysis units. The final part of this contribution is devoted to the emission values of fl ue gases from pyrolysis plant.W artykule podsumowano możliwości odzysku energii z odpadów komunalnych i innych rodzajów odpadów. Opisano rozwój technologii spalania i odzysku energii z odpadów komunalnych w Czechosłowacji, a następnie w Czechach. Zwrócono uwagę na trzy obecnie eksploatowane instalacje do odzysku energii z odpadów komunalnych działające w Republice Czeskiej (ZEVO Malešice, SAKO Brno, TERMIZO Liberec i ZEVO Chotíkov). Przedstawiono charakterystykę planowanych instalacji do odzysku energii z odpadów komunalnych w Republice Czeskiej. Wszystkie zakłady działają zasadniczo w oparciu o kotły rusztowe z oczyszczaniem spalin na najwyższym poziomie technicznym. W artykule przedstawiono również inne technologie, które mogą być wykorzystane do odzysku energii z odpadów komunalnych – instalacje do zgazowania i pirolizy. Ostatnia część artkułu poświęcona jest analizie poziomu emisji gazów spalinowych z instalacji do pirolizy

Potencjał paliw z odpadów komunalnych

The article summarizes possibilities of energy recovery from municipal waste. It describes the history of incineration and energy recovery from municipal waste in Czechoslovakia and then in the Czech Republic. The attention is paid to the three currently operated plants for energy recovery from municipal waste in the Czech Republic (ZEVO Malešice, SAKO Brno and TERMIZO Liberec). The following are the characteristics of the planned plants for energy recovery from municipal waste in the Czech Republic. All these plants operate essentially based on grate boilers with flue gas treatment at the highest technical level. The article also lists other technologies which can be used for energy recovery from municipal waste – these are gasification and pyrolysis units and plasma technology. The conclusion of this contribution is devoted to the current and future situation in the area of energy recovery from municipal waste in the Czech Republic.Artykuł podsumowuje możliwości odzysku energii z odpadów komunalnych. Opisuje historię spalania oraz odzysku energii z odpadów komunalnych w Czechosłowacji oraz późniejszych Czechach. Zwrócono tu uwagę na trzy obecnie działające zakłady odzyskiwania energii w Czechach (ZEVO Malesive, SAKO Brno oraz TERMIZO Liberec). Następnie przedstawiono charakterystykę planowanych zakładów odzyskiwania energii z odpadów komunalnych w Czechach. Wszystkie te zakłady pracują bazując na kotłach rusztowych z obróbką gazów wylotowych na najwyższym możliwym poziomie technologicznym. Artykuł zestawia również inne technologie, które mogą być zastosowane do odzyskiwania energii z odpadów komunalnych – należy do nich gazyfikacja i piroliza oraz technologia plazmowa. Podsumowanie tej pracy jest poświęcone obecnej oraz przyszłej sytuacji w obszarze odzysku energii z odpadów komunalnych w Czechach