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Mesoporous silica particles (MCM-41) decorated with Ag nanoparticles were prepared by the template ion exchange (TIE) method. The properties of the synthesized material were investigated by several techniques, including the nitrogen sorption measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR). Moreover, the degradability of the particles was tested in simulated body fluid (SBF) in order to evaluate the degradation rate of the material. The silica particles were loaded with different Ag concentrations but no structural changes were observed in the ordered mesoporosity. Already after 1 day of immersion in SBF most of the silver particles were released and partial degradation of the silica particles was observed. Ibuprofen was loaded into the Ag containing MCM-41 particles in order to evaluate their drug up-take/release capability. Silver and silicon ion release was quantified with inductively coupled plasma optical emission spectroscopy (ICP-OES). The novel silver doped MCM-41 particles were used as a functional coating on bioactive glass (BG) based scaffolds intended for bone tissue engineering application. [ABSTRACT FROM AUTHOR]

Background: Giant cavernous carotid aneurysms (GCCAs) usually exert substantial mass effect on adjacent intracavernous cranial nerves. Since predictors of cranial nerve deficits (CNDs) in patients with GCCA are unknown, we designed a study to identify associations between CND and GCCA morphology and the location of mass effect.Methods: This study was based on data from the prospective clinical and imaging databases of the Giant Intracranial Aneurysm Registry. We used magnetic resonance imaging and digital subtraction angiography to examine GCCA volume, presence of partial thrombosis (PT), GCCA origins, and the location of mass effect. We also documented whether CND was present.Results: We included 36 GCCA in 34 patients, which had been entered into the registry by eight participating centers between January 2009 and March 2016. The prevalence of CND was 69.4%, with one CND in 41.7% and more than one in 27.5%. The prevalence of PT was 33.3%. The aneurysm origin was most frequently located at the anterior genu (52.8%). The prevalence of CND did not differ between aneurysm origins (p = 0.29). Intracavernous mass effect was lateral in 58.3%, mixed medial/lateral in 27.8%, and purely medial in 13.9%. CND occurred significantly more often in GCCA with lateral (81.0%) or mixed medial/lateral (70.0%) mass effect than in GCCA with medial mass effect (20.0%; p = 0.03). After adjusting our data for the effects of the location of mass effect, we found no association between the prevalence of CND and aneurysm volume (odds ratio (OR) 1.30 (0.98-1.71); p = 0.07), the occurrence of PT (OR 0.64 (0.07-5.73); p = 0.69), or patient age (OR 1.02 (95% CI 0.95-1.09); p = 0.59).Conclusions: Distinguishing between medial versus lateral location of mass effect may be more helpful than measuring aneurysm volumes or examining aneurysm thrombosis in understanding why some patients with GCCA present with CND while others do not.Clinical trial registration no.: NCT02066493 (clinicaltrials.gov) [ABSTRACT FROM AUTHOR]

Bioactive glass (BG) based scaffolds (45S5 BG composition) were developed by the replica technique using natural marine sponges as sacrificial templates. The resulting scaffolds were characterized by superior mechanical properties (compression strength up to 4 MPa) compared to conventional BG scaffolds prepared using polyurethane (PU) packaging foam as a template. This result was ascribed to a reduction of the total scaffold porosity without affecting the pore interconnectivity (>99%). It was demonstrated that the reduction of total porosity did not affect the bioactivity of the BG-based scaffolds, tested by immersion of scaffolds in simulated body fluid (SBF). After 1 day of immersion in SBF, a homogeneous CaP deposit on the surface of the scaffolds was formed, which evolved over time into carbonate hydroxyapatite (HCA). Moreover, the enhanced mechanical properties of these scaffolds were constant over time in SBF; after an initial reduction of the maximum compressive strength upon 7 days of immersion in SBF (to 1.2 ± 0.2 MPa), the strength values remained almost constant and higher than those of BG-based scaffolds prepared using PU foam (<0.05 MPa). Preliminary cell culture tests with Saos-2 osteoblast cell line, namely direct and indirect tests, demonstrated that no toxic residues remained from the natural marine sponge templates and that cells were able to proliferate on the scaffold surfaces. [ABSTRACT FROM AUTHOR]

Unruptured intracranial aneurysms represent a decisional challenge. Treatment risks have to be balanced against an unknown probability of rupture. A better understanding of the physiopathology is the basis for a better prediction of the natural history of an individual patient. Knowledge about the possible determining factors arises from a careful comparison between ruptured versus unruptured aneurysms and from the prospective observation and analysis of unbiased series with untreated, unruptured aneurysms. The key point is the correct identification of the determining variables for the fate of a specific aneurysm in a given individual. Thus, the increased knowledge of mechanisms of formation and eventual rupture of aneurysms should provide significant clues to the identification of rupture-prone aneurysms. Factors like structural vessel wall defects, local hemodynamic stress determined also by peculiar geometric configurations, and inflammation as trigger of a wall remodeling are crucial. In this sense the study of genetic modifiers of inflammatory responses together with the computational study of the vessel tree might contribute to identify aneurysms prone to rupture. The aim of this article is to underline the value of a unifying hypothesis that merges the role of geometry, with that of hemodynamics and of genetics as concerns vessel wall structure and inflammatory pathways. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the safety and efficacy of a new liquid embolic agent in brain arteriovenous malformation (bAVMs) embolisation. Methods: A prospective, multicentre series was conducted at 11 interventional centres in Europe to evaluate embolisation of bAVMs with the new liquid embolic agent. Technical conditions, complications, clinical outcome and anatomical results were independently analysed. Results: From December 2005 to December 2008, 117 patients (72 male; 45 female, aged 18-75 years) were included. Clinical presentation was mostly haemorrhage (34.2 %) and seizures (28.2 %). Most AVMs were located in the brain hemispheres (85.5 %). AVMs were <3 cm in 52.1 % of patients and ≥3 cm in 47.9 %. Morbidity was observed in 6/117 patients (5.1 %), related to haemorrhagic events in 2 cases and non-haemorrhagic complications in 4 cases. Five patients (4.3 %) died in relation to the treatment (bleeding in 4 patients and extensive venous thrombosis in 1). Complete occlusion of the AVM by embolisation alone was obtained in 23.5 % of patients. Complementary treatment was performed in 82.3 % of patients with partial AVM occlusion, mostly radiosurgery. Conclusions: In this prospective, multicentre, European, observational series, the new liquid embolic agent proved to be suitable for BAVM embolisation, with acceptable morbidity and mortality and good efficacy. Key Points: • Numerous interventional techniques have been used to embolise brain arteriovenous malformations (AVMs). • This prospective multicentre study demonstrates the suitability of a liquid embolic agent. • The safety of treatment using Onyx is acceptable. • Such embolisation leads to complete AVM occlusion in 23.5 % of patients. [ABSTRACT FROM AUTHOR]

Aneurysms of the vertebro-basilar junction area have been considered the most difficult to be surgically treated because of their deep location, the proximity of the brain stem and the cranial nerves. However, at present, new endovascular techniques and new transbasal surgical approaches offer valuable management strategies. This paper concerns six consecutive patients whom we managed either endovascularly or surgically during a period of eighteen months. Direct surgical treatment was offered to two young patients with relatively small aneurysms in good neurological condition, whereas the other four patients initially underwent an endovascular attempt at aneurysm obliteration using the Guglielmi detachable coil system. Unfortunately, interventional neuroradiology failed in three cases, and surgery had to be re-considered. Accordingly, a total of five patients underwent surgical clipping through the combination of a transmastoid retrolabyrinthine approach with the suboccipital lateral approach. This combination of approaches provided a good control of both vertebral arteries and basilar artery, and allowed the aneurysm to be correctly clipped in all cases. Good long-term results were achieved in all cases but one. Based on this preliminary experience, we would stress the importance of a multidisciplinary approach with a treatment calibrated for each single case. Furthermore, if surgery is to be performed, the combination of transmastoid-retrolabyrinthine and suboccipital lateral approaches provides a wide exposure of the whole vertebro-basilar junction area and allows good access to the lesion. [ABSTRACT FROM AUTHOR]