During their lifecycle, many marine organisms rely on natural adhesives to attach to wet surfaces for movement and self-defense in aqueous tidal environments. Adhesive proteins from mussels are biocompatible and elicit only minimal immune responses in humans. Therefore these proteins have received increased attention for their potential applications in medicine, biomaterials, and biotechnology. The Asian green mussel Perna viridis secretes several byssal plaque proteins, molecules that help anchoring the mussel to surfaces. Among these proteins, protein-5β (Pvfp-5β) initiates interactions with the substrate, displacing interfacial water molecules before binding to the surface. Here, we established the first recombinant expression in Escherichia coli of Pvfp-5β. We characterized recombinant Pvfp-5β, finding that despite displaying a CD spectrum consistent with features of a random coil, the protein is correctly folded as indicated by MS and NMR analyses. Pvfp-5β folds as a β-sheet–rich protein as expected for an epidermal growth factor-like module. We examined the effects of Pvfp-5β on cell viability and adhesion capacity in NIH-3T3 and HeLa cell lines, revealing that Pvfp-5β has no cytotoxic effects at the protein concentrations used and provides good cell-adhesion strength on both glass and plastic plates. Our findings suggest that the adhesive properties of recombinant Pvfp-5β make it an efficient surface-coating material, potentially suitable for biomedical applications including regeneration of damaged tissues.

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Background: Weaning from tracheostomy has implications in management, quality of life, and costs of ventilated patients. Furthermore, endotracheal cannula removing needs further studies. Aim of this study was the validation of a protocol for weaning from tracheostomy and evaluation of predictor factors of decannulation. Methods: Medical records of 48 patients were retrospectively evaluated. Patients were decannulated in agreement with a decannulation protocol based on the evaluation of clinical stability, expiratory muscle strength, presence of tracheal stenosis/granulomas, deglutition function, partial pressure of CO2, and PaO2/FiO2 ratio. These variables, together with underlying disease, blood gas analysis parameters, time elapsed with cannula, comordibity, Barthel index, and the condition of ventilation, were evaluated in a logistic model as predictors of decannulation. Results: 63 % of patients were successfully decannulated in agreement with our protocol and no one needed to be re-cannulated. Three variables were significantly associated with the decannulation: no pulmonary underlying diseases (OR = 7.12; 95 % CI 1.2–42.2), no mechanical ventilation (OR = 9.55; 95 % CI 2.1–44.2) and period of tracheostomy ≤10 weeks (OR = 6.5; 95 % CI 1.6–27.5). Conclusions: The positive course of decannulated patients supports the suitability of the weaning protocol we propose here. The strong predictive role of three clinical variables gives premise for new studies testing simpler decannulation protocols.

BackgroundWeaning from tracheostomy has implications in management, quality of life, and costs of ventilated patients. Furthermore, endotracheal cannula removing needs further studies. Aim of this study was the validation of a protocol for weaning from tracheostomy and evaluation of predictor factors of decannulation.MethodsMedical records of 48 patients were retrospectively evaluated. Patients were decannulated in agreement with a decannulation protocol based on the evaluation of clinical stability, expiratory muscle strength, presence of tracheal stenosis/granulomas, deglutition function, partial pressure of CO2, and PaO2/FiO2 ratio. These variables, together with underlying disease, blood gas analysis parameters, time elapsed with cannula, comordibity, Barthel index, and the condition of ventilation, were evaluated in a logistic model as predictors of decannulation.Results63 % of patients were successfully decannulated in agreement with our protocol and no one needed to be re-cannulated. Three variables were significantly associated with the decannulation: no pulmonary underlying diseases (OR = 7.12; 95 % CI 1.2–42.2), no mechanical ventilation (OR = 9.55; 95 % CI 2.1–44.2) and period of tracheostomy ≤10 weeks (OR = 6.5; 95 % CI 1.6–27.5).ConclusionsThe positive course of decannulated patients supports the suitability of the weaning protocol we propose here. The strong predictive role of three clinical variables gives premise for new studies testing simpler decannulation protocols.

Oxidative stress and mitochondrial dysfunction play an important role in the onset of neurodegenerative diseases; thus, the antioxidant use could be a promising preventive or therapeutic intervention. The food and agricultural industries generate huge quantities of by-products rich in biophenolic compounds. If, on the one hand, they represent a serious environmental problem, on the other hand, are valuable natural sources of antioxidants. In the present work, the total phenolic content and the antioxidant power of the wastewater derived from the production of four Sicilian extra virgin olive oils are shown. Four biophenols, hydroxytyrosol and tyrosol alcohols and caffeic acid (CA) and p-coumaric acids, were identified and quantified and their antioxidant ability determined. Their effects in counteracting Abeta 1-42 oligomer oxidative damage in LAN5 cell culture were investigated. Results indicated that CA was the most effective compound in counteracting the cell damages induced by Abeta 1-42 oligomers. El contenido valioso de aguas residuales producidas por almazaras: el efecto protector de la fracción antioxidante en cultivos celulares RESUMEN El estrés oxidativo y la disfunción mitocondrial juegan un rol importante en el comienzo de ciertas enfermedades neurodegenerativas; en estos casos, el uso de antioxidantes puede ser una intervención preventiva o terapéutica prometedora. Las industrias alimentarias y agrícolas producen enormes cantidades de subproductos ricos en compuestos biofenólicos. Si bien por un lado representan un grave problema ambiental, por el otro constituyen valiosas fuentes naturales de antioxidantes. En el presente estudio se analizan el contenido fenólico total y el poder antioxidante de las aguas residuales (WW) derivadas de la producción de cuatro aceites de oliva virgen extra (AOVE) de Sicilia. Para el efecto, Se identificaron y cuantificaron cuatro biofenoles, alcoholes hidroxitirosol (HT) y tirosol (TY), además de ácidos cafeico (CA) y p-cumárico (CU), y se determinó su capacidad antioxidante. Asimismo, se investigaron sus efectos para contrarrestar el daño oxidativo provocado por el oligómero Abeta 1-42 en cultivos celulares LAN5, constatándose que el CA fue el más efectivo para contrarrestar el daño celular inducido por oligómeros Abeta 1-42 .

Recognizing the complexity of the fibrillogenesis process provides a solid ground for the development of therapeutic strategies aimed at preventing or inhibiting protein-protein aggregation. Under this perspective, it is meaningful to identify the possible aggregation pathways and their relative products. We found that Aβ-peptide dissolved in a pH 7.4 solution at small peptide concentration and low ionic strength forms globular aggregates without typical amyloid β-conformation. ThT binding kinetics was used to monitor aggregate formation. Circular dichroism spectroscopy, AFM imaging, static and dynamic light scattering were used for structural and morphological characterization of the aggregates. They appear stable or at least metastable with respect to fiber growth, therefore appearing as an incidental product in the pathway of fibrillogenesis.

Similar to its bacterial homolog GroEL, Hsp60 in oligomeric conformation is known to work as a folding machine, with the assistance of co-chaperonin Hsp10 and ATP. However, recent results have evidenced that Hsp60 can stabilize aggregation-prone molecules in the absence of Hsp10 and ATP by a different, “holding-like” mechanism. Here, we investigated the relationship between the oligomeric conformation of Hsp60 and its ability to inhibit fibrillization of the Ab40 peptide. The monomeric or tetradecameric form of the protein was isolated, and its effect on beta-amyloid aggregation was separately tested. The structural stability of the two forms of Hsp60 was also investigated using differential scanning calorimetry (DSC), light scattering, and circular dichroism. The results showed that the protein in monomeric form is less stable, but more effective against amyloid fibrillization. This greater functionality is attributed to the disordered nature of the domains involved in subunit contacts.

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