SVILUPPO DI SUPPORTI POLIMERICI TRIDIMENSIONALI IN POLICAPROLATTONE PER IL TRATTAMENTO DI LESIONI OSSEE CON PERDITA DI SOSTANZA CRITICA: STUDIO SPERIMENTALE IN VIVO.

RIASSUNTO Le lesioni ossee con perdita di sostanza, conseguenti a traumi, osteomieliti o resezioni di tumori, rappresentano una complicazione clinica di frequente riscontro. Il tessuto osseo ha la capacità di rigenerare spontaneamente ma, in presenza di un difetto critico, il processo ripartivo può spesso esitare in un fallimento. Scopo del presente studio è stato quello di allestire supporti tridimensionali, biocompatibili e biodegradabili, in poli-ε-caprolactone con struttura molecolare a stella (*PCL) caricati con antibiotici (Enrofloxacina o Levofloxacina) o altri fattori promotori della rigenerazione ossea (Idrossiapatite - HA) e valutare la loro efficacia nel promuovere e sostenere la rigenerazione ossea in lesioni con grave perdita di sostanza complicate da concomitante infezione. Sono stati ottimizzati i parametri di processo e sono state valutate la morfologia delle strutture ottenute per wet-spinning, l’efficacia di caricamento e di rilascio dei farmaci rispettivamente nelle e dalle fibre. Per lo studio delle capacità di adesione e proliferazione cellulare sulle guide, sono state impiegate cellule pre-osteoblastiche murine. Le capacità osteoinduttive, osteoconduttive e osteointegrative di scaffolds in *PCL e*PCL-HA con forma e dimensioni anatomiche sono state testate in difetti critici di 20mm creati sulla diafisi radiale di coniglio. Lo studio ha mostrato l’efficacia della tecnica di wet-spinning nel permettere l’allestimento di strutture tridimensionali con diversa forma e con microstruttura controllata. Le prove in vitro di rilascio degli antibiotici caricati negli scaffolds hanno evidenziato un rilascio inizialmente veloce che poi tende a stabilizzarsi a una velocità costante per oltre un mese. Le prove di coltura cellulare hanno mostrato una buona vitalità e proliferazione in tutto lo spessore degli scaffolds. Le prove in vivo su modello cunicolo hanno mostrato una discreta rigenerazione ossea con segni di rimodellamento evidenti alla dodicesima settimana post-impianto. Il tessuto osseo neoformato è risultato costituito sia da osso lamellare sia intrecciato e localizzato sul versante laterale della struttura, in prossimità dell’ulna. La rimanente porzione di scaffold, non interessata da rigenerazione del tessuto osseo, è apparsa occupata da tessuto connettivo fibroso. I risultati promettenti ottenuti nel presente studio suggeriscono il possibile impiego degli scaffolds a base di *PCL testati come supporti per l’ingegneria ossea, da impiegare per il trattamento di lesioni critiche a carico di ossa lunghe. ABSTRACT Bone defects resulting from trauma, osteomyelitis and tumor resection are common clinical problems. Bone tissue usually has the ability to regenerate, but when a defect of critical size needs to be bridged, the repair attempt to fails in most cases. Aim of this study was to optimize the technique of preparation of a biocompatible and biodegradable three-dimensional star poly-ε-caprolactone (*PCL) scaffold loaded with antibiotics (Enrofloxacin or Levofloxacin) or bone regeneration promoting factors (Hydroxyapatite – HA), to assess its possible application in the treatment of bone lesions with substance loss complicated by outbreaks of infection. Morphology of micro-structured scaffolds obtained by wet-spinning, efficiency of drugs loading and drug release kinetics were evaluated. Cell culture experiments employing a murine pre-osteoblast cell line were performed to evaluate cell viability and proliferation on *PCL scaffolds. Osteoinduction, osteoconduction and osteointegration of anatomically-shaped *PCL and *PCL-HA meshes were evaluated in a 20mm critical-size diaphyseal radius defect in a rabbit model. This study showed the efficiency of wet-spinning technique to produce three-dimensional scaffolds with different shapes and controlled microstructure. The in vitro release kinetics of the meshes, under physiological conditions, was initially fast and then a sustained release for more than one month was observed. Cell culture experiments showed good viability, adhesion and proliferation on the wet-spun *PCL fibers throughout the whole scaffolds. In vivo tests showed a good bone regeneration with bone remodeling 12 weeks after implantation. The newly formed bone tissue was lamellar and woven at the lateral edge of the scaffold, near the ulna. The remaining part of the scaffold, not infiltrated by bone tissue, appeared rich in fibrous connective tissue. The promising results attained in the present work suggest a potential application of the developed *PCL meshes as engineered bone scaffolds for the treatment of long-bone critical-size defects

Exploring pro-environmental behavior of religious tourists based on motivations: the case of Assisi visitors

Abstract Purpose – The pro-environmental behavior of tourists is becoming a topic of growing interest for both scholars and policymakers, given the numerous implications that it can determine. Recent studies have considered the role of visitor motivations for the adoption of on-site sustainable practices. This research fits into this debate, delving into the case of religious destinations, assessing if travel motivations can determine behaviors more or less oriented toward protecting the environment. Design/methodology/approach – Considering a sample of individuals who visited Assisi in the second half of 2022, a cluster analysis focused on the intensity of the motives of the visit was performed, followed by a confirmatory factor analysis centered on pro-environmental behavior and by a simple linear regression. Findings – Three clusters of visitors (the “Poorly Spiritual – Cultural - Escape – Motivated (S-C-E-M),” the “Spirituals” and the “Strongly Spiritual – Cultural – Escape – Motivated (S-C-E-M”) emerged, with a different propensity to adopt pro-environmental behavior. Strongly S-C-E-M visitors, driven by cultural, spiritual and escape motives, adopt pro-environmental behavior to a greater extent than the other two groups; the spirituals are placed in an intermediate position, while the poorly S-C-E-M are the least accustomed to sustainability practices. Originality/value – The paper fits into the debate concerning the antecedents of pro-environmental behavior, focusing on travel motivations. It offers a new perspective for understanding the implementation of sustainability practices by visitors to religious places, highlighting that spirituality can be a catalyst for proenvironmental behavior, but its power increases if it is accompanied by other types of motivations such as cultural and escape

Action Mechanisms of the Secondary Metabolite Euplotin C: Signaling and Functional Role in Euplotes

Among secondary metabolites, the acetylated hemiacetal sesquiterpene euplotin C has been isolated from the marine, ciliated protist Euplotes crassus, and provides an effective mechanism for reducing populations of potential competitors through its cytotoxic properties. However, intracellular signaling mechanisms and their functional correlates mediating the ecological role of euplotin C are largely unknown. We report here that, in E. vannus (an Euplotes morphospecies which does not produce euplotin C and shares with E. crasssus the same interstitial habitat), euplotin C rapidly increases the intracellular concentration of both Ca2+ and Na+, suggesting a generalized effect of this metabolite on cation transport systems. In addition, euplotin C does not induce oxidative stress, but modulates the electrical properties of E. vannus through an increase of the amplitude of graded action potentials. These events parallel the disassembling of the ciliary structures, the inhibition of cell motility, the occurrence of aberrant cytoplasmic vacuoles, and the rapid inhibition of phagocytic activity. Euplotin C also increases lysosomal pH and decreases lysosomal membrane stability of E. vannus. These results suggest that euplotin C exerts a marked disruption of those homeostatic mechanisms whose efficiency represents the essential prerequisite to face the challenges of the interstitial environmental.L'articolo è disponibile sul sito dell'editore http://onlinelibrary.wiley.com

Subsidence of Artificial Reefs with Bamboo Foundations on a Soft Seabed

The design of artificial reefs must be based on the criteria of both durability and serviceability. In this respect, the seabed subsidence rate related to the weight of the reefs and of their foundation system should be limited. The horizontal drift of the reefs during their life should be small too. In this study, pertaining to the behavior of artificial reefs made of microsilica concrete and realized with foundations in bamboo near the international airport of Hong Kong, 1-year monitoring data and calculations of reef foundation settlements are shown and discussed to assess the performance of the adopted mixed foundation and to deduce the nature of the long-term subsidence. The subsidence related to the settlements of the foundations was monitored using a Multibeam Echo Sounder System. It was found that the observed subsidence rate cannot be justified by the primary consolidation of the soils forming the seabed. Indeed, secondary consolidation seems to play an important role. Overall, after one year of service, the artificial reefs are considered to be effective in terms of limitation of both subsidence and drift

An Environmentally Friendly Practice Used in Olive Cultivation Capable of Increasing Commercial Interest in Waste Products from Oil Processing

In the Rural Development Plan (2014–2020), the European Commission encouraged the conversion and supported the maintenance of organic farming. Organic olive oil (bioEVOO) production involves the use of environmentally sustainable fertilizers and the recycling of olive pomace (Pom) and olive vegetation waters (VW) to reduce the environmental impact of these wastes. An ecofriendly way to recycle olive wastes is to reuse them to extract bioactive compounds. In this study, the total phenolic compounds content, their profile and dosage, the antioxidant action in oil, pomace, and vegetation water was evaluated when the Trichoderma harzianum M10 was used as a biostimulant in agriculture. Two spectrophotometric tests (2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic) acid (ABTS)) evaluated the antioxidant potential of samples, a spectrophotometric method estimated total phenolic content, and an Ultra‐High‐Performance Liquid Chromatography (UHPLC)–Orbitrap method evaluated the phenolics profile. Our results showed that the biostimulation improved the antioxidant potential and the total concentration of phenolics in the bioEVOO and bio‐pomace (bioPom) samples and mainly enhanced, among all classes of phenolic compounds, the production of the flavonoids and the secoiridoids. Moreover, they demonstrated the Trichoderma action in the mevalonate pathway to produce phenols for the first time. The decisive action of the Thricoderma on the production of phenolic compounds increases the economic value of the waste materials as a source of bioactive compounds useful for the pharmaceutical, cosmetic, and food industries

An Investigation on the Role of Spike Latency in an Artificial Olfactory System

Experimental studies have shown that the reactions to external stimuli may appear only few hundreds of milliseconds after the physical interaction of the stimulus with the proper receptor. This behavior suggests that neurons transmit the largest meaningful part of their signal in the first spikes, and than that the spike latency is a good descriptor of the information content in biological neural networks. In this paper this property has been investigated in an artificial sensorial system where a single layer of spiking neurons is trained with the data generated by an artificial olfactory platform based on a large array of chemical sensors. The capability to discriminate between distinct chemicals and mixtures of them was studied with spiking neural networks endowed with and without lateral inhibitions and considering as output feature of the network both the spikes latency and the average firing rate. Results show that the average firing rate of the output spikes sequences shows the best separation among the experienced vapors, however the latency code is able in a shorter time to correctly discriminate all the tested volatile compounds. This behavior is qualitatively similar to those recently found in natural olfaction, and noteworthy it provides practical suggestions to tail the measurement conditions of artificial olfactory systems defining for each specific case a proper measurement time

Anodal Transcranial Direct Current Stimulation over the Cerebellum Enhances Sadness Recognition in Parkinson's Disease Patients: a Pilot Study

Emotional processing impairments, resulting in a difficulty to decode emotions from faces especially for negative emotions, are characteristic non-motor features of Parkinson's disease (PD). There is limited evidence about the specific contribution of the cerebellum to the recognition of emotional contents in facial expressions even though patients with cerebellar dysfunction often lose this ability. In this study, we aimed to evaluate whether the recognition of facial expressions can be modulated by cerebellar transcranial direct current stimulation (tDCS) in PD patients. Nine PD patients were enrolled and received anodal and sham tDCS (2 mA, 20 min), for 5 consecutive days, in two separate cycles at intervals of at least 1 month. The facial emotion recognition task was administered at baseline (T0) and after cerebellar tDCS on day 5 (T1). Our preliminary study showed that anodal cerebellar tDCS significantly enhanced emotional recognition in response to sad facial expressions by about 16%, but left recognition of anger, happiness, and neutral facial expressions unchanged. Despite the small sample size, our preliminary results show that anodal tDCS applied for five consecutive days over the cerebellum modulates the way PD patients recognize specific facial expressions, thus suggesting that the cerebellum plays a crucial role in recognition of negative emotions and corroborating previous knowledge on the link between social cognition and the cerebellum