Electrospun ECM macromolecules as biomimetic scaffold for regenerative medicine: challenges for preserving conformation and bioactivity

The extracellular matrix (ECM), the physiological scaffold for cells in vivo, provides structural support to cells and guaranties tissue integrity. At the same time, however, it represents an extremely complex and finely tuned signaling environment that contributes in regulating tissue homeostasis and repair. ECM can bind, release and activate signaling molecules and also modulate cell reaction to soluble factors. Cell-ECM interactions, as a result, are recognized to be critical for physiological wound healing, and consequently in guiding regeneration. Due to its complexity, mimicking ECM chemistry and architecture appears a straightforward strategy to exploit the benefits of a biologically recognizable and cell-instructive environment. As ECM consists primarily of sub-micrometric fibers, electrospinning, a simple and versatile technique, has attracted the majority efforts aimed at reprocessing of biologically occurring molecules. However, the ability to trigger specific cellular behavior is likely to depend on both the chemical and conformational properties of biological molecules. As a consequence, when ECM macromolecules are electrospun, investigating the effect of processing on their structure, and the extent to which their potential in directing cellular behavior is preserved, appears crucial. In this perspective, this review explores the electrospinning of ECM molecules specifically focusing on the effect of processing on polymer structure and on in vitro or in vivo experiments designed to confirm the maintenance of their instructive role

Il castagno in Italia: condizioni preliminari e vincoli normativi

Il castagno è una specie dalle mille utilità e possiamo dire anche dalle "mille regolamentazioni". A livello nazionale viene normato in base al tipo di produzione e alle modalità di coltivazione; a livello regionale le indicazioni per la gestione risultano spesso eterogenee, non in linea con le caratteristiche ecologiche della specie e, sopratutto, non aggiornate rispetto alle evidenze scientifiche di cui oggi disponiamo

Otter diet and prey selection in a recently recolonized area assessed using microscope analysis and DNA barcoding

Ecologists traditionally investigate the feeding ecology of vertebrates by visual identification of prey in their scats using a microscope. This analysis, however, presents some pitfalls, such as poor prey identification at genus/species level. DNA barcoding is an alternative to the traditional diet analysis, recently applied to investigate the diet of several vertebrates. It allows the identification of cryptic or not-recognizable prey portions basing their identification on the analysis of conserved DNA fragments. Here, we combined microscope analysis with DNA barcoding to investigate the diet of the Eurasian otter (Lutra lutra) in an area recently recolonized by the species, in the surroundings of Tarvisio, NE Italy. We collected 102 spraints and analysed all of them at microscope. A random subsample (N=50) was then analysed through DNA barcoding, via amplification of the V9 region of the SSU 18S-rDNA 18S gene. Furthermore, we assessed seasonal variation in otter diet and whether otters select certain salmonids size classes, to identify potential conflict with anglers. According to the microscope analysis, otters ate primarily fish (salmonids and European bullhead), secondarily amphibians and, more rarely, crayfish, both annually and seasonally. DNA barcoding analysis confirmed the microscope results, attributing some salmonids sequences to the brown trout (Salmo trutta). The lack of potential prey species reference sequences in the GenBank database hampered us in identifying the other taxa found in the spraints at more informative levels. Consumed salmonids and bullheads were of small size. In particular, otters selected salmonids size class of 100 mm, which is much smaller than the minimum catchable size for angling. Overall, our study confirms DNA barcoding potential for otter diet analyses, highlighting the need of additional markers to improve molecular prey identification and suggesting that otters do not constitute a significant threat to anglers in the area

Electrospun silk fibroin–gelatin composite tubular matrices as scaffolds for small diameter blood vessel regeneration

In this work an innovative method to obtain natural and biocompatible small diameter tubular structures is proposed. The biocompatibility and good mechanical properties of electrospun silk fibroin tubular matrices (SFts), extensively studied for tissue engineering applications, have been coupled with the excellent cell interaction properties of gelatin. In fact, an innovative non-cytotoxic gelatin gel, crosslinked in mild conditions via a Michael-type addition reaction, has been used to coat SFt matrices and obtain SFt/gel structures (I.D. = 6 mm). SFts/gel exhibited homogeneous gelatin coating on the electrospun fibrous tubular structure. Circumferential tensile tests performed on SFts/gel showed mechanical properties comparable to those of natural blood vessels in terms of UTS, compliance and viscoelastic behavior. Finally, SFt/gel in vitro cytocompatibility was confirmed by the good viability and spread morphology of L929 fibroblasts up to 7 days. These results demonstrated that SFt/gel is a promising off-the-shelf graft for small diameter blood vessel regeneration

Il recupero del castagneto da legno

Quali sono le migliori tecniche da adottare per recuperare alla produzione legnosa i cedui castanili fuori turno? Grazie alla sperimentazione svolta siamo oggi in grado di indicare le migliori condizioni per l'applicazione di buone pratiche di successo. Anche se, nel caso del castagno, la parola chiave rimane una sola: ceduazione

Opzioni gestionali per i cedui castanili fuori turno

La scelta della migliore opzione gestionale per un ceduo di castagno oltre il turno consuetudinario si deve basare: sulle caratteristiche del soprassuolo, sull'analisi delle caratteristiche stazionali, sulla funzione attesa dal popolamento, sull'eventuale rischio di pericoli naturali, sulle condizioni logistiche e sul contesto sociale

Sistemi selvicolturali per i cedui di castagno

Per "sistema selvicolturale" s'intende l'insieme di operazioni messe in atto per la coltura, l'utilizzazione e la messa in rinnovazione di un bosco. I sistemi selvicolturali indicati per il governo a ceduo del castagneto variano in funzione degli obiettivi specifici, ma possono essere raggruppati in due diverse categorie di selvicoltura: quella di popolamento e quella d'albero. In questo contributo ne descriviamo le principali caratteristiche, finalità e modalità d'applicazione

Natural seed regeneration in chestnut coppices: a key factor in planning silvicultural management.

Over the last 50 years, many unfavourable factors have led to the abandonment of the traditional management of many chestnut coppices. This generated a general aging of the stands and a related reduction of the slope stability, emphasizing the importance of natural regeneration for future forest management. Natural regeneration from seed contributes to the increase of the stem density, provides new stools for future coppice generations and promotes the proper development of the stand in terms of specific and structural diversity. In this study we tested the effect of different silvicultural treatments in coppice stands on the seed regeneration potential of the chestnut tree. The chestnut seed regeneration resulted to be influenced by: I) the age of the stand at felling time (increasing age was related to a greater presence of regeneration from seed), II) the cover of released over-aged trees (light conditions on the soil), III) microclimatic conditions (drought stress in particular). Overall, the natural regeneration dynamics in chestnut coppices revealed to be a useful reference to identify some general guidelines for sustainable interventions aiming to foster chestnut regeneration, while maintaining biodiversity in an effort to improve the quality of timber assortments