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Enhancing the Potency of Antimicrobial Peptides through Molecular Engineering and Self-Assembly
Healthcare-associated infections resulting from bacterial attachment and biofilm formation on medical implants are posing significant challenges in particular with the emergence of bacterial resistance to antibiotics. Here, we report the design, synthesis and characterization of self-assembled nanostructures, which integrate on their surface antibacterial peptides. The antibacterial WMR peptide, which is a modification of the native sequence of the myxinidin, a marine peptide isolated from the epidermal mucus of hagfish, was used considering its enhanced activity against Gram-negative bacteria. WMR was linked to a peptide segment of aliphatic residues (AAAAAAA) containing a lipidic tail (C19H38O2) attached to the ε-amino of a terminal lysine to generate a peptide amphiphile (WMR PA). The self-assembly of the WMR PA alone, or combined with coassembling shorter PAs, was studied using spectroscopy and microscopy techniques. The designed PAs were shown to self-assemble into stable nanofiber structures and these nanoassemblies significantly inhibit biofilm formation and eradicate the already formed biofilms of Pseudomonas aeruginosa (Gram-negative bacteria) and Candida albicans (pathogenic fungus) when compared to the native WMR peptide. Our results provide insights into the design of peptide based supramolecular assemblies with antibacterial activity, and establish an innovative strategy to develop self-assembled antimicrobial materials for biomedical applications
Analysis and control of genetic toggle switches subject to periodic multi-input stimulation
Characterization of building materials from the Anfiteatro Flavio (Pozzuoli, southern Italy): a mineralogical and petrographic study
This work is the result of a geoarchaeological investigation on the Anfiteatro Flavio, one of the most important archaeological sites in the Campania region (southern Italy), situated in an area of great geological and archaeological interest, the Campi Flegrei volcanic field. The aim of this research was to characterise building stones employed for structural use, focusing on the type of materials and their provenance. The mineralogical-petrographic characterization of 27 samples from corbels and pillars involved X-ray powder diffraction analyses (XRPD), thin section optical microscopy observations (OM) and energy dispersive spectrometry microanalyses (EDS). The results revealed that the source materials are represented by two distinctive trachytic/phonolitic lava deposits. Pillar light grey block samples are made of a feldspar-phyric (F-p) lava type that shares many petrographic and mineral chemical features with the Campi Flegrei Accademia lava dome, cropping out in the immediate proximities of the Anfiteatro Flavio. On the other hand, pillar grey block and corbel samples are made of an alkali feldspar and sodalite-phyric (KS-p) lava that has been correlated to an Ischian lava deposit based mainly of the peculiar composition of the observed amphibole crystals. Previous data attesting for the use of the Piperno welded tuff for the pillar grey blocks were likely driven by the “eutaxitic-like” fluidal oriented texture and by the alveolitization alteration displayed by the samples. This however does not exclude that the Piperno had been employed as a building stone for other structural elements of the amphitheatre. The use of the Ischia lavas as an exported building material had been never reported before, possibly suggesting that current knowledges about the use and trade of building materials in the Campania area during the Roman period need to be reconsidered
How do energy balance-related behaviors cluster in adolescents?
BJECTIVES: To delineate the clustering of energy balance-related behaviors in adolescents and investigate whether these behaviors are associated with the household socioeconomic status and parental education level.
METHODS: Two cross-sectional studies assessed information on sedentary behavior, physical activity, sugar-sweetened beverages and fruit and vegetable consumption, and sleep duration by self-reported questionnaires in adolescents (12.5-17.5years old) from Maringa/Brazil (BRACAH Study; n=682) and ten European cities (HELENA Study; n=1252) from nine different countries. Gender-specific cluster analyses were performed separately for each study, applying a combination of hierarchical and non-hierarchical methods.
RESULTS: Girls showed equivalent behaviors: Sedentary; Active; Unhealthy Eating; Healthy Eating; while boys differed (Brazilian: Sedentary; Active; Healthy Eating; European: Sedentary; Healthy; Unhealthy Eating). In Brazil, we found no association between socioeconomic status and parental education. In European girls, the high socioeconomic status and both parents' university degree were associated with Healthy Eating. In European boys, the high socioeconomic status was associated with Unhealthy Eating, and the mothers' university degree was associated with the Healthy cluster.
CONCLUSIONS: Adolescents show Sedentary behavior, regardless of their sex, country of origin, or socioeconomic condition
Licenziamento collettivo nei gruppi di imprese alla luce dell’orientamento più innovativo della Suprema Corte: codatorialità ed interesse comune?
Il contributo ha analizzato le questioni della codatorialità e dell'interesse comune nei gruppi di imprese facendo riferimento alle principali posizioni dottrinali per poi considerare gli attuali sviluppi interpretativi nell'orientamento più innovativo della Suprema Corte manifestando, in proposito, dubbi sulla riconducibilità della "codatorialità" nell'ambito della categoria dell'obbligazione soggettivamente complessa.
By referring to the main doctrinal positions on the subject, the contribution analyzed the issues of “codatorialità” and common interest in groups of companies in order to consider the most innovative orientation of the Supreme Court, expressing doubts about the consideration of "codatorialità" as a subjectively complex obligation
EXISTING-BIM: INTEGRATED SURVEY PROCEDURES FOR THE MANAGEMENT OF MODERN ARCHITECTURE
This paper is aimed at illustrating the operation workflow to create a BIM model of an existing building, by highlighting its process starting from photogrammetric acquisitions and indicating its critical elements as regards data structure and the following modeling. The subject of this study is a reinforced concrete building of the 1960s on six levels. At present, it is undergoing an extensive refurbishment with the purpose of converting its original function, from the US Navy Hospital into offices. Since it was possible to access archive documents concerning the executive design and to carry out even invasive surveys for acquiring specific data about building details, BIM modeling could refer to a significant amount of qualitative and quantitative data. This circumstance characterized the work steps of a BIM modeling which, although referred to an existing building, may also be applied to new constructions. Building technology has implicitly facilitated the identification of the constructive elements and the creation of a list, although the unusual shape of the structure has caused specific problems differently discussed and documented in the text
Prostate MRI technical parameters standardization: A systematic review on adherence to PI-RADSv2 acquisition protocol
The Prostate Imaging-Reporting and Data System has been developed to standardize prostate MRI in terms of acquisition, interpretation and reporting. It received a major revision in late 2014 (PI-RADSv2). Recently, doubts have been raised on imaging facilities adherence to its acquisition protocol. With this systematic review, we assessed adherence to PI-RADSv2 minimum technical specifications in literature, to achieve a better understanding of issues limiting their diffusion
SYNTHESIS AND CHARACTERIZATION OF NEW SILIBININ PHOSPHODIESTER CONJUGATES: EXPLORING THEIR PROPERTIES.
Polyphenols are active compounds from medicinal plants widely distributed in nature. Many reports suggest that the mechanisms by which plant polyphenols exert their protective actions against various diseases are in part due to their redox properties [1]. Silibinin, belonging to flavonolignan class, is the major component of Silymarin complex extracted from the fruits of milk thistle (Silybum marianum) [2]. Silibinin is a diastereoisomeric mixture of two flavonolignans, Silybin A and Silybin B, in a ratio of approximately 1:1; this metabolite has long been studied for its large variety of pharmacological properties ranging from the antioxidant to neuroprotective [3] and antiviral activities. Unfortunately, many drug candidates including Silibinin, even if have been reported to possess a strong therapeutic potential in vitro, fail in vivo because of their poor bioavailability, often connected to a low water solubility. The design and synthesis of water-soluble pro-drugs are a powerful approach in order to overcome these limits and to improve the pharmacological potentialities of these compounds [4].
In this regard, here, we report the synthesis and characterization of new phosphodiester Silibinin conjugates by the insertion of a phosphate group at the 9” position. This, besides improving the Silibinin water solubility, allows conjugation of different molecules (Figure) able to recognize cell targets and to improve Silibinin pharmaceutical properties [5-8]. The new derivatives have been tested in different radical scavenging assays. A antiviral and neuroprotective activities have also been explored