Hydrogel scaffolds blends to host Spheroids from human adipose stem cells

INTRODUCTION Adipose stem cells represent a reliable source of stem cells for their widely demonstrated potential in regenerative medicine and tissue engineering applications. New recent insights show that 3D models may properly mimic the native tissue properties; in fact Spheroids from Adipose derived Stem Cells (S-ASCs) displayed enhanced regenerative abilities if compared to 2D models. Stem cell therapy success is determined by "cell-quality" thus the involvement of stress signals and cellular aging need to be deeply investigated. The development of 3D cell-laden hydrogels has enabled to mimic the peculiar scenario of a native tissue. We studied SASCs-cell quality and tested their viabil…

Hydrogel scaffolds based on k-Carrageenan/xyloglucan blends to host spheroids from human adipose stem cells

Hydrogels are water-swollen networks of hydrophilic polymer. They can be fabricated in various shapes and swell in water or aqueous solutions maintaining their original shape or undergo progressive erosion; can exibit large volume phase transitions with the change of one environmental parameter (stimuli-responsivness), shock absorption and low sliding friction properties (1). The morphology and mechanical properties of hydrogels are strongly affected by the network composition, the nature and degree of crosslinking and the degree of swelling. Indeed, when hydrogels are designed as scaffolds for human tissues remodeling, they must have sufficient mechanical integrity to provide support to th…

Idrogeli a base di xiloglucano e k-carragene con sferoidi di cellule staminali adipose umane come scaffolds per la medicina rigenerativa

Con l’obiettivo di sviluppare scaffold per la rigenerazione dei tessuti umani con sferoidi di cellule staminali adipose (S-ASC), questo lavoro indaga le proprietà degli idrogeli formati da dei polisaccaridi che subiscono transizioni sol-gel indotte dalla temperatura e le loro miscele: k-carragene (k-C) e xiloglucano parzialmente degalattosilato (Deg-XG). Gli idrogeli sono network polimerici idrofili rigonfiati dall'acqua. La morfologia e le proprietà meccaniche degli idrogeli sono fortemente influenzate dalla loro composizione, grado di reticolazione e di rigonfiamento. Quando sono progettati come scaffold, devono avere sufficiente integrità meccanica per fornire supporto alle cellule, dall…

Adipose stem cell spheroids-laden hydrogels for minimally invasive bone and cartilage regeneration interventions

Agarose/k-Carrageenan-based hydrogel films enriched with natural extracts for wound healing applications

Hydrogels are 3D hydrophilic networks that can hold significant amounts of water within their structure, without dissolving in water.

Radiation engineered nanogels as platforms for medical diagnostics and therapeutic nanodevices

A scalable, single step, synthetic approach for the manufacture of biocompatible, functionalized microgels and nanogels has been developed. Pulsed EB irradiation of PVP aqueous solutions, at relatively low energies per pulse and doses within the sterilization dose range, has led to a variety of ‘as-born’ sterile, functional nanostructures that exhibit a combination of favourable properties which make them suitable as biomedical nanocarriers. Reactive functional groups have been generated by graft copolymerization of functional acrylic monomers. These groups can be used to attach fluorescent probes to the NPs, to bioconjugate ligands of specific cell receptors and to incorporate therapeutics…

Frontal sinus osteoma and palpebral abscess: Case report

Osteomas of the paranasal sinuses are slow-growing, benign tumours most frequently found in the frontal sinus with an incidence that varies from 47% to 80% of the cases; there are often no symptoms and they are diagnosed by chance during an x-ray examination. The symptoms are usually headaches and those secondary to ocular or neurological complications. The therapy to be preferred is surgery. The authors describe a case of frontal osteoma complicated by frontal sinusitis and palpebral abscess.

Miscele di k-carragenina e PVA come bio-inchiostri per stampa 3D di scaffold per la ricostruzione della cartilagine

Introduzione La k-carragenina (kC) è un poligalattano solfato ottenuto da alghe rosse con un contenuto di estere-solfato dal 25 al 30% e una peso molecolare medio ben superiore a 100 kDa. È formato da unità alternate di D-galattosio e 3,6-anidro-galattosio (3,6-AG) unite da legami α-1,3 e β-1,4-glicosidici. [1] Il kC assomiglia ai glicosaminoglicani (GAG) che sono i costituenti centrali dei tessuti connettivi, può essere quindi studiato per produrre scaffold per l'ingegneria tissutale. Il kC è solubile in acqua a temperature superiori a 60 °C e può formare gel stabili raffreddandosi. Le reti di kC sono forti, fragili e l'assenza di porosità interconnesse può limitare la colonizzazione dell'…

Idrogeli con sferoidi di cellule staminali adipose per interventi mini-invasivi di rigenerazione ossea o cartilaginea

Introduzione Lo xiloglucano (XG) è un polisaccaride sia di struttura che di riserva, perché svolge il ruolo di matrice nelle pareti cellulari delle piante superiori ma è anche presente in alcuni semi, tra i quali tamarindo. Lo xiloglucano da semi di tamarindo è disponibile in commercio, è un polimero biocompatibile, approvato dalla FDA per uso alimentare. È caratterizzato da uno scheletro di β-(1, 4)-D-glucano parzialmente sostituito da α-(1, 6)-D-xilosio e β-(1, 2)-D-galattossilosio. La scissione enzimatica di alcuni dei residui di galattosio fornisce allo XG proprietà di gelificazione indotte da variazioni di temperatura. In particolare, quando viene rimosso il 35% circa dei residui di ga…

Carbon fibre composite materials produced by gamma radiation induced curing of epoxy resins

It is well known that ionizing radiation can initiate polymerization of suitable monomers for many applications. In this work an epoxy dlfunctional monomer has been used as matrix of a carbon fibre composite in order to produce materials through gamma radiation, for aerospace and advanced automotive applications. Radiation curing has been performed at different absorbed doses and, as comparison, also thermal curing of the same monomer formulations has been done. Furthermore some Irradiated samples have been also subjected to a post Irradiation thermal curing in order to complete the polymerization reactions. The properties of the cured materials have been studied by moisture absorption isot…

E-beam curing of epoxy based blends in order to produce high performance composites

In this work, blends of a difunctional epoxy monomer and a thermoplastic toughening agent are E-beam irradiated at two different dose rates and two different total absorbed doses. The influence of the processing conditions on the thermal properties and on the morphology of the obtained matrices has been investigated. In particular, it is shown how the increase of the dose rate causes an increase of the temperature during irradiation, thus inducing a simultaneous thermal and radiation curing. On the contrary, at low-dose rate the system mainly undergoes to radiation curing, thus making the cured material very sensible to a post-irradiation thermal treatment with a significant improvement of …

Agarose/k-Carrageenan-based hydrogel films enriched with natural extracts for wound healing applications

Hydrogels are 3D hydrophilic networks that can hold significant amounts of water within their structure, without dissolving in water. They can offer a combination of favorable properties, including high absorbency of biological fluids, biocompatibility, biodegradability, stimuli-responsiveness, high storage capacity and release ability of small and large therapeutic molecules. The hydrogel films designed for wound dressing may accomplish several functions, playing an important role in the healing processes. They can absorb and retain the wound exudates, stimulating fibroblast proliferation and keratinocyte migration and promoting re-epithelialization. Furthermore, they can incorporate and r…

Exploring nose-to-brain insulin delivery as a new strategy for the treatment of Alzheimer’s disease

A growing body of evidence shows that Insulin, Insulin Receptor (IR) and IR signaling are involved in brain cognitive functions and their dysfunction is implicated in Alzheimer’s disease (AD) degeneration. Thus, administration of insulin could be a strategy for AD treatment. For this aim we designed, synthesized and characterized a nanogel system (NG) to deliver insulin to the brain, as a tool for the development of a new therapy for AD. A carboxyl-functionalized poly(N-vinyl pyrrolidone) nanogel system produced by high energy ionizing radiation was chosen as substrate for the covalent attachment of insulin or fluorescent molecules, relevant for its tracing

Studies of network organization and dynamics of e-beam crosslinked PVPs: From macro to nano

Abstract In this work the influence of poly(N-vinyl pyrrolidone) (PVP) concentration in water on the organization and dynamics of the corresponding macro-/nanogel networks has been systematically investigated. Irradiation has been performed at the same irradiation dose (within the sterilization dose range) and dose rate. In the selected irradiation conditions, the transition between macroscopic gelation and micro-/nanogels formation is observed just below the critical overlap concentration (∼1 wt%), whereas the net prevalence of intra-molecular over inter-molecular crosslinking occurs at a lower polymer concentration (below 0.25 wt%). Dynamic–mechanical spectroscopy has been applied as a cl…

TREATMENT OF FIBROUS HYPERPLASIA OF THE MAXILLARY TUBEROSITY AND PALATE WITH RADIO FREQUENCY AND FIBRIN GLUE: A CASE REPORT

Injectable hydrogel formulations to host adipose stem cell spheroids for stemness maintenance and bone and cartilage regeneration

Adipose-derived mesenchymal stem cells (ASCs) represent a great promise for tissue regeneration as fat is a very abundant source of stem cells (1) and owing to their ability to self-renew and differentiate into specific tissue types (2). In general, they are usually cultured as two-dimensional (2D) adherent monolayers, not representative of the in vivo condition, often entailing lower cell viability and, more in general, a lower “cell quality” in terms of regenerative potential (3, 4). When ASCs are cultured in low adhesion flasks and with a suitable culture medium, they aggregate in the form of three-dimensional spheroids (SASCs). The incorporation of these spheroids into injectable, in-si…

k-Carrageenan and PVA blends as 3D printing bioinks for cartilage reconstruction scaffolding

Endoscopic treatment of maxillary sinus mucocele

Important Biomolecular Indicators In Locally Advanced Laryngeal Squamous Carcinoma: P16 Mutations

Experiments on heat transfer in evaporators for refrigerating plants working with new fluids and data correlation

Frontal sinus osteoma complicated by palpebral abscess: case report.

Epoxy resin-thermoplastic blends cured by ionising radiation. Structure/properties relationships

Radiation curing of an epoxy resin based blend is carried out in order to produce polymer matrices for high-performance composites. A suitable choice of both curing process and formulation parameters allows to irradiate at about 60°C. Moreover hydrothermal ageing is performed on cured materials and their properties have been evaluated

Glutathione-sensitive nanogels for drug release

Nanogels (NGs) synthesized by pulsed electron-beam irradiation of semi-dilute poly (N-vinyl pyrrolidone) (PVP) aqueous solutions, at relatively low energy per pulse and doses within the sterilization dose range, represent a very interesting family of polymeric nanocarriers. Ionizing irradiation-induced crosslinking of PVP allows to control particle size, and surface chemistry of the polymer nanoparticles without making use of catalysts, organic solvents or surfactants, and with beneficial effects onto the purity and hence biocompatibility of the final products obtained. Furthermore, the availability of reactive functional groups, either generated by the radiation or purposely grafted via co…

Metodologie di analisi energetica nei supermercati e negli ipermercati, con l’obiettivo della ottimizzazione della domanda elettrica ed energetica globale, casi studio per la Regione Siciliana

Metodologie di analisi energetica nei supermercati e negli ipermercati, con l’obiettivo della ottimizzazione della domanda elettrica ed energetica globale, casi studio per la Regione Siciliana