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The study focuses on the design and evaluation of electrospun dual function scaffolds with the ability to heal inflammation in skin and eye tissues and to provide topographical cues for cells penetration into the scaffolds depth. For this purpose scaffolds were loaded with antibiotic and electrospun on 3D printed collectors with purpose made geometry.

Authors’ very first experience with application of glycerol preserved allografts (GPAs) in acute burn treatment applied in a 7-year-old boy with 93% TBSA IIIrd degree flame burn. After excision of the necrotic tissue during the initial 4 days, INTEGRA DRT was applied on the extremities. Given the fact that the take rate of INTEGRA DRT was around 30%, allogenic skin grafts were imported from the Banc de Sang i Teixits - Barcelona and grafted onto the wound bed, 14 days after the patient’s admission. Donor sites on the scalp and the foot were covered with amniotic membranes (AM) from the local Tissue Bank. During 4 months of hospitalization, GPAs were applied 6 times (7, 000 cm2). AM promoted faster healing in small areas of IInd degree burns. Cadaveric skin grafts enabled the preservation of the wound bed for subsequent autologous skin grafting combined with cultured epithelial autografts (CEAs). CEAs were applied in preconfluent phase with two - component fibrin glue (Tisseel, Baxter). The take rate after wound bed conditioning with allogenic skin was around 90%. An episode of mold infection occurred on the area covered with allogenic skin what prompted immediate removal of the grafts and initiation of antifungal therapy. Allogenic skin grafts provided a beneficial temporary wound dressing and enabled a very satisfying take rate of autologous skin grafts. Unfortunately, six months after the admission, when burns were healed, the patient died out of acute heart failure.

Femoral head allografts removed as the surgical surplus bone tissue during the total hip arthroplasty procedure represent valuable clinic material, especially if cadaveric grafts are not available. Nevertheless, care must be taken that extensive safety and quality control measures during the femoral heads banking are fulfilled. In the Clinic for traumatology, these allografts are used as the method for repairing large bone defects providing optimal implant fixation and long-term support for the components. We examined the clinical use of femoral head allografts in our Clinic since 2010 in which structural allografts showed best available option for bone defect reconstruction in trauma and orthopaedic, spinal and other surgical procedures. Femoral head allografts were mostly used for different indications of operative grafting procedures in the treatment of proximal and distal tibial and fibular (31, 4%), femoral (29, 27%), humeral (20, 21%), calcaneal, pelvic and vertebral fractures. Proximal tibia fractures included B and C type of fracture were treated with different quality of bone healing results. Femoral head allografts have some drawbacks like lack of the specific osteosynthetic material, low growth potential at recipient’s site and lower quality of the cavernous bone tissue (old donors). Despite all of this, frozen bone allografts provided by our local Tissue Bank are of great importance, particularly in situation where the use of autograft could pose an additional health risk to a patient.

Thermoplastic polyurethane (TPU) has been extensively studied in the field of tissue engineering. Incorporation of titanium dioxide (TiO2) into TPU scaffold benefits further with its antimicrobial, photo-catalytic, anticorrosive and hydrophilic properties that are very desirable in ocular regenerative medicine. We decided to test this new, combined material for biocompatibility with human corneal cells

Enzimska hidroliza pulpe šećerne repe (PŠR) provedena je u Erlenmeyer tikvicama na laboratorijskoj tresilici, korištenjem enzimskih otopina pripravljenih tijekom uzgoja Trametes multicolor, Sclerotium rolfsii i Neurospora crassa na različitim supstratima. Najbolji rezultati ostvareni su korištenjem enzimskih otopina Sclerotium rolfsi uzgojene na PŠR i celulozi. Optimalni uvjeti hidrolize u tikvicama na laboratoriskoj tresilici ostvareni su u vodenim otopinama s 66 g/L PŠR pri 40 °C, 150 okr/min i koncentraciji enzima od 5 ml/L. Povećanje koncentracije enzima nije pogodovalo povećanju koncentraciji reducirajućih šećera, ali je kombinacijom enzimskih otopina S1c i S1sb te dodatkom pulpe u obrocima tri puta po 22 g/L odnosno 44 g/L PŠR ostvareno povećanje koncentracije reducirajućih šećera na razinu pogodnu za proizvodnju bioetanola (52, 46 g/L).

Enzimska hidroliza pulpe šećerne repe (PŠR), klipa kukuruza i drvnih ostataka provedena je u Erlenmeyer tikvicama na laboratorijskoj tresilici, korištenjem enzimskih otopina pripravljenih tijekom uzgoja Trametes multicolor, Sclerotium rolfsii i Neurospora crassa na različitim supstratima. Najbolji rezultati ostvareni su hidrolizom PŠR korištenjem enzimskih otopina Sclerotium rolfsi uzgojene na PŠR i celulozi. Optimalni uvjeti hidrolize u tikvicama na laboratoriskoj tresilici ostvareni su u vodenim otopinama s 66 g/L PŠR pri 40 ^oC, 150 okr/min i koncentraciji enzima od 5 ml/L. Povećanje koncentracije enzima nije pogodovalo povećanju koncentraciji reducirajućih šećera, ali je kombinacijom enzimskih otopina S1c i S1sb te dodatkom pulpe u obrocima tri puta po 22 g/L odnosno 44 g/L PŠR ostvareno povećanje koncentracije reducirajućih šećera na razinu pogodnu za proizvodnju bioetanola (52, 46 g/L). Hidroliza PŠR provedena je i u bioreaktorima s lopatastim i turbinskim miješalom. Izmjerene koncentracije reducirajućih šećera bile su niže od prethodno izmjerenih tijekom eksperimenata u tikvicama na laboratoriskoj tresilici (16, 0 g/L odnosno 25, 00 g/L).

Sugar beet pulp (SBP) is a valuable lignocellulose’s waste raw material for bioethanol production. Bioethanol production process consists of following steps: lignocellulose pretreatment, fermentation and bioethanol separation and purification. Lignocellulose pretreatment is the main step for successful bioethanol production and wide investigation efforts were performed in order to develop the new efficient and cheap pretreatment method. Different physical, chemical and biological pretreatment methods could be used depending on the lignocellulose material source and composition. In this study, combination of physical and biological pretreatment was utilized in two consecutive steps. In the first step, thermal treatment or ultrasound disruption and in the second step enzymatic hydrolysis was used, respectively. For the enzyme hydrolysis commercial cellulases as well as combination of commercial cellulases and pectinases were utilized. Ultrasound disruption of SBP was carried out by ultrasound homogenisator SONOPLUS HD 2200 in continuous mode for 15 min with 50% of maximum power (max. 0.2 kW). Thermal treatment was performed at 121 OC for 15 min. Commercial cellulases (CN) and pectinases (PN) were used for the hydrolysis of SBP. Determination of hydrolyzed substrates and fermentation products was performed by high-pressure liquid chromatography (HPLC). It is obvious from obtained results that both pretreatment methods (thermal and ultrasound) of SBP have great potential for successful degradation of lignocellulose’s raw material. This observation can be most easily proved by the increase of mono– and disaccharide concentrations in cultivation medium. The extraction of remain sucrose (Suc) from SBP was considerably supported by the ultrasound treatment of SBP. Degradation of the lignocelluloses components of SBP to glucose (Glc) and galactose (Gal) was significantly increased by the thermal treatment. The treatment of SBP with celluloses and pectinases was related to the increase of glucose (Glc), galactose (Gal), arabinose (Ara) and galacturonic acid (GalA) concentrations. On the basis of obtained results it is clear that the combination of thermal treatment and enzyme hydrolysis is the most efficient SBP pretreatment method for bioethanol production.

Cilj ovog rada bila je procjena stupanja onečišćenja priobalnog mora srednjeg i južnog Jadrana na temelju kvantitativnog određivanja anionskih tenzida u uzorcima morske vode. Uzorci površinskog sloja morske vode prikupljeni su na 13 postaja u različitim godišnjim dobima tijekom jedne godine (od ožujka 2008. do travanja 2009.). Utvrđene koncentracije anionskih tenzida (izražene kao μg MBAS/l) ukazale su da sve postaje onečišćenja anionskim tenzidima ukazuju na značajan utjecaj ljudske aktivnosti na morske ekosustave ovih područja. Izmjerene vrijednosti su ukazale da je najveće onečišćenje anionskim tenzidima zabilježeno na području splitske plaže Bačvice, što se smatra da je posljedica neposrednog ispusta neobrađenih komunalnih voda u more.