Maria Stella Tarico

Evaluation of nanostructured lipid carriers (NLC) and nanoemulsions as carriers for UV-filters: characterization, in vitro penetration and photostability studies.

The increased awareness of protection against UV radiation damages has led to a rise in the use of topically applied chemical sunscreen agents and to an increased need of innovative carriers designed to achieve the highest protective effect and reduce the toxicological risk resulting from the percutaneous absorption of these substances. In this paper, nanostructured lipid carriers (NLC) and nanoemulsions (NE) were formulated to optimize the topical application of different and widespread UVA or UVB sun filters (ethyl hexyltriazone (EHT), diethylamino hydroxybenzoyl hexyl benzoate (DHHB), bemotrizinol (Tinosorb S), octylmethoxycinnamate (OMC) and avobenzone (AVO)). The preparation and stability parameters of these nanocarriers have been investigated concerning particle size and zeta potential. The release pattern of the sunscreens from NLC and NE was evaluated in vitro, determining their percutaneous absorption through excised human skin. Additional in vitro studies were performed in order to evaluate, after UVA radiation treatment, the spectral stability of the sunfilters once formulated in NLC or NE. From the results obtained, when incorporated in NLC, the skin permeation abilities of the sun filter were drastically reduced, remaining mainly on the surface of the skin. The photostability studies showed that EHT, DHHB and Tinosorb S still retain their photostability when incorporated in these carriers, while OMC and AVO were not photostable as expected. However, no significant differences in terms of photoprotective efficacy between the two carriers were observed.

Lipid Nanoparticles as Carrier for Octyl-Methoxycinnamate: In Vitro Percutaneous Absorption and Photostability Studies

The aim of the present study was the evaluation of lipid nanoparticles (solid lipid nanoparticles, SLN, and nanostructured lipid carriers, NLC) as potential carriers for octyl-methoxycinnamate (OMC). The release pattern of OMC from SLN and NLC was evaluated in vitro, determining its percutaneous absorption through excised human skin. Additional in vitro studies were performed in order to evaluate, after UVA radiation treatment, the spectral stability of OMC-loaded lipid nanoparticles. From the obtained results, ultrasonication method yielded both SLN and NLC in the nanometer range with a high active loading and a particle shape close to spherical. Differential scanning calorimetry data pointed out the key role of the inner oil phase of NLC in stabilizing the particle architecture and in increasing the solubility of OMC as compared with SLN. In vitro results showed that OMC, when incorporated in viscosized NLC dispersions (OMC-NLC), exhibited a lower flux with respect to viscosized SLN dispersions (OMC-SLN) and two reference formulations: a microemulsion (OMC-ME) and a hydroalcoholic gel (OMC-GEL). Photostability studies revealed that viscosized NLC dispersions were the most efficient at preserving OMC from ultraviolet-mediated photodegradation.

Design of solid lipid nanoparticles for caffeine topical administration

Abstract Context: Solid lipid nanoparticles (SLN) are drug carriers possessing numerous features useful for topical application. A copious scientific literature outlined their ability as potential delivery systems for lipophilic drugs, while the entrapment of a hydrophilic drug inside the hydrophobic matrix of SLN is often difficult to obtain. Objective: To develop SLN intended for loading caffeine (SLN-CAF) and to evaluate the permeation profile of this substance through the skin once released from the lipid nanocarriers. Caffeine is an interesting compound showing anticancer and protective effects upon topical administration, although its penetration through the skin is compromised by its hydrophilicity. Materials and methods: SLN-CAF were formulated by using a modification of the quasi-emulsion solvent diffusion technique (QESD) and characterized by PCS and DSC analyses. In vitro percutaneous absorption studies were effected using excised human skin membranes (i.e. Stratum Corneum Epidermis or SCE). Results: SLN-CAF were in a nanometric range (182.6 ± 8.4 nm) and showed an interesting payload value (75% ± 1.1). DSC studies suggest the presence of a well-defined system and the successful drug incorporation. Furthermore, SLN-CAF generated a significantly faster permeation than a control formulation over 24 h of monitoring. Discussion and conclusions: SLN-CAF were characterized by valid dimensions and a good encapsulation efficiency, although the active to incorporate showed a hydrophilic character. This result confirms the suitability of the formulation strategy employed in the present work. Furthermore, the in vitro evidence outline the key role of lipid nanoparticles in enhancing caffeine permeation through the skin.

The Role of Nanofat Grafting in Vulvar Lichen Sclerosus: A Preliminary Report

Since the discovery of adipose-derived adult stem (ADAS) cells in adipose tissue [1], many studies have articulated a new concept of lipofilling, which is no longer seen as adipocyte grafting, but rather as stem cell transplantation.

An unusual case of symptomatic Schwannoma on the elbow

This case report regards a Schwannoma originating from the ulnar nerve at the elbow. It produced a variety of symptoms and severely impaired the patients hand function. The surgical procedure consisted in the enucleation of the swelling and the anterior submuscular transposition of the ulnar nerve.

Lateral Nasal Artery Perforator Flaps: Anatomic Study and Clinical Applications

Background Previous studies have investigated facial artery perforators, but have reported inconsistent results regarding lateral nasal artery (LNA) perforators. Although several authors have described the use of LNA perforators for ala nasi and nasal sidewall reconstruction, the literature contains little information regarding the cadaveric dissection of LNA perforators, and most previously published studies have focused on facial artery perforators. Methods Sixteen hemifaces from eight fresh cadavers were dissected to study the LNA perforators. After the dissection was performed, the total length and diameter of the LNA and its perforators were measured. The quantity and the distribution of the LNA perforators supplying the overlying skin were then assessed. LNA perforator flaps were used for reconstruction in 10 nasal and perinasal defects. Results The mean total lengths of the LNA and its perforators were 49.37 mm and 16.06 mm, respectively. The mean diameters of the LNA and its perforators were 2.08 mm and 0.91 mm, respectively. Based on our findings, we mapped the face to indicate zones with a higher probability of finding perforators. No infection, hematoma, or complete flap necrosis were observed after the procedures. Conclusions Nasal reconstruction is a challenging procedure, and LNA propeller/V-Y perforator flaps are an excellent reconstructive option in certain cases. Based on our cadaveric study, we were able to identify an area in the upper third of the nasolabial groove with a high density of perforators.

Reverse Flow Shunt Restricted Arterialized Venous Free Flap

Several technical modifications have been described to avoid complications of venous flaps. The authors describe a technical variation of the venous flap to reduce the risk of venous congestion and the likelihood of shunting, thus increasing venous flap reliability.

Neural differentiation of human adipose-derived mesenchymal stem cells induced by glial cell conditioned media

Adipose‐derived mesenchymal stem cells (ASCs) may transdifferentiate into cells belonging to mesodermal, endodermal, and ectodermal lineages. The aim of this study was to verify whether a neural differentiation of ASCs could be induced by a conditioned medium (CM) obtained from cultures of olfactory ensheathing cells (OECs) or Schwann cells (SCs). ASCs were isolated from the stromal vascular fraction of adipose tissue and expanded for 2–3 passages. They were then cultured in OEC‐CM or SC‐CM for 24 hr or 7 days. At each stage, the cells were tested by immunocytochemistry and flow cytometer analysis to evaluate the expression of typical neural markers such as Nestin, PGP 9.5, MAP2, Synapsin I, and GFAP. Results show that both conditioned media induced similar positive effects, as all tested markers were overexpressed, especially at day 7. Overall, an evident trend toward neuronal or glial differentiation was not clearly detectable in many cases. Nevertheless, a higher tendency toward a neuronal phenotype was recognized for OEC‐CM (considering MAP2 increases). On the other hand, SC‐CM would be responsible for a more marked glial induction (considering GFAP increases). These findings confirm that environmental features can induce ASCs toward a neural differentiation, either as neuronal or glial elements. Rather than supplementing the culture medium by adding chemical agents, a “more physiological” condition was obtained here by means of soluble factors (cytokines/growth factors) likely released by glial cells. This culture strategy may provide valuable information in the development of cell‐based therapeutic approaches for pathologies affecting the central/peripheral nervous system.

Principi di terapia chirurgica

Accanto all’esperienza pratica chirurgica e alla padronanza delle tecniche operatorie, e presupposto fondamentale all’esecuzione di operazioni dermatologiche la capacita; di inquadrare dal punto di vista diagnostico differenziale le lesioni dermatologiche e il tipo di tecnica chirurgica appropriata al singolo caso (per esempio, la scelta del margine di sicurezza per i diversi tipi di tumori, la scelta della tecnica chirurgica piu adatta, oppure di procedimenti alternativi come la crioterapia, la laser-terapia ecc.).