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Abdominal hernia repair is a frequently performed surgical procedure worldwide. Currently, the use of polypropylene (PP) surgical meshes for the repair of abdominal hernias constitutes the primary surgical approach, being widely accepted as superior to primary suture repair. Surgical meshes act as a reinforcement for the weakened or damaged tissues and support tissue restoration. However, implanted meshes could suffer from poor integration with the surrounding tissues. In this context, the present study describes the preliminary evaluation of a PCL-Gel-based nanofibrous coating as an element to develop a multicomponent hernia mesh device (meshPCL-Gel) that could overcome this limitation thanks to the presence of a nanostructured biomimetic substrate for enhanced cell attachment and new tissue formation. Through the electrospinning technique, a commercial PP hernia mesh was coated with a nanofibrous membrane from a polycaprolactone (PCL) and gelatin (Gel) blend (PCL-Gel). Resulting PCL-Gel nanofibers were homogeneous and defect-free, with an average diameter of 0.15 ± 0.04 μm. The presence of Gel decreased PCL hydrophobicity, so that membranes average water contact angle dropped from 138.9 ± 1.1° (PCL) to 99.9 ± 21.6°, while it slightly influenced mechanical properties, which remained comparable to those of PCL (E = 15.7 ± 2.7 MPa, σR= 7.7 ± 0.6 εR = 118.8 ± 13.2%). Hydrolytic and enzymatic degradation was conducted on PCL-Gel up to 28 days, with maximum weight losses around 20 and 40%, respectively. The meshPCL-Gel device was obtained with few simple steps, with no influences on the original mechanical properties of the bare mesh, and good stability under physiological conditions. The biocompatibility of meshPCL-Gel was assessed by culturing BJ human fibroblasts on the device, up to 7 days. After 24 h, cells adhered to the nanofibrous substrate, and after 72 h their metabolic activity was about 70% with respect to control cells. The absence of detectable lactate dehydrogenase in the culture medium indicated that no necrosis induction occurred. Hence, the developed nanostructured coating provided the meshPCL-Gel device with chemical and topographical cues similar to the native extracellular matrix ones, that could be exploited for enhancing the biological response and, consequently, mesh integration, in abdominal wall hernia repair.

Hyperthermia is a technique for destroying cancer cells which involves the exposition of body's tissue to a controlled heat, normally between 41 C and 46 C. It has been reported that ferro-or ferrimagnetic materials can heat locally, if they are placed (after being implanted) under an alternating magnetic field, damaging only tumoral cells and not the healthy ones. The power loss produced by the magnetic materials can be dissipated in the form of heat. This phenomenon has to be regulated in order to obtain a controlled temperature inside the tissues. The material that was produced and characterized in this work is composed of two phases: a polymethylmethacrylate (PMMA) matrix in which a ferrimagnetic biocompatible/bioactive glass ceramic is dispersed. This composite material is intended to be applied as bone filler for the hyperthermic treatment of bone tumors. The ferrimagnetic bioactive glassceramic belongs to the system SiO 2 -Na 2 O-CaO-P 2 O 5 -FeO-Fe 2 O 3 and contains magnetite (FeO*Fe 2 O 3 ) inside an amorphous bioactive residual phase. The composite material possesses structural, magnetic and bioactivity properties. The structural ones are conferred by PMMA which acts as filler for the bone defect or its damaged area. Bioactivity is conferred by the composition of the residual amorphous phase of the glass-ceramic and magnetic properties are conferred by magnetite crystals embedded in the bioactive glass-ceramic. The characterization involved the following tests: morphological and chemical characterization (scanning electron microscopy-energy dispersion spectrometry-micro computed tomography analysis), calorimetric tests and mechanical test (compression and flexural four point test). In vitro assessment of biological behavior will be the object of the part II of this work.

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Background: The role of thrombus aspiration plus primary percutaneous coronary intervention in ST-segment elevation myocardial infarction remains controversial. Methods: We performed a meta-analysis of 25 randomised controlled trials in which 21,740 ST-segment elevation myocardial infarction patients were randomly assigned to thrombus aspiration plus primary percutaneous coronary intervention or primary percutaneous coronary intervention. Study endpoints were: death, myocardial infarction, stent thrombosis and stroke. Results: On pooled analysis, the risk of death (4.3% vs. 4.8%, odds ratio (OR) 0.90, 95% confidence interval (CI) 0.79-1.03; P=0.123), myocardial infarction (2.4% vs. 2.5%, OR 0.95, 95% CI 0.80-1.13; P=0.57) and stent thrombosis (1.3% vs. 1.6%, OR 0.80, 95% CI 0.63-1.01; P=0.066) was similar between thrombus aspiration plus primary percutaneous coronary intervention and primary percutaneous coronary intervention. The risk of stroke was higher in the thrombus aspiration plus primary percutaneous coronary intervention than the primary percutaneous coronary intervention group (0.84% vs. 0.59%, OR 1.401, 95% CI 1.004-1.954; P=0.047). However, on sensitivity analysis after removing the TOTAL trial, thrombus aspiration plus primary percutaneous coronary intervention was not associated with an increased risk of stroke (OR 1.01, 95% CI 0.58-1.78). The weak association between thrombus aspiration and stroke was also confirmed by the fact that the lower bound of the 95% CI was slightly below unity after removing either the study by Kaltoft or the ITTI trial. There was no interaction between the main study results and follow-up, evidence of coronary thrombus, or study sample size. Conclusions: In patients with ST-segment elevation myocardial infarction, thrombus aspiration plus primary percutaneous coronary intervention does not reduce the risk of death, myocardial infarction or stent thrombosis. Thrombus aspiration plus primary percutaneous coronary intervention is associated with an increased risk of stroke; however, this latter finding appears weak.