67 research outputs found
Fast Coprecipitation of Calcium Phosphate Nanoparticles inside Gelatin Nanofibers by Tricoaxial Electrospinning
We present an effective method for fabricating electrospun gelatin nanofibers containing well-dispersed inorganic nanoparticles. The new method encompasses the use of a special triaxial needle where mixing calcium and phosphate aqueous solutions in an intermediate needle yield calcium phosphate (CaP) nanoparticles that immediately after precipitation are dragged by the outer polymeric solution and incorporated directly in the electrospinning jet, before nanofiber formation. Gelatin electrospun mats containing different amounts of CaP nanoparticles were prepared and characterized by SEM, TEM, TGA, and stress-strain measurements. The results demonstrate that CaP particles having diameter of few tens of nanometers were successfully introduced in the gelatin nanofibers during the electrospinning process and that they were well dispersed throughout the fiber length. In addition, the use of the special triaxial needle enabled modulating the CaP amount in the nanofibers
A novel phage-library-selected peptide inhibits human TNF-α binding to its receptors
We report the identification of a new human tumor necrosis factor-alpha (TNF-α) specific peptide selected by competitive panning of a phage library. Competitive elution of phages was obtained using the monoclonal antibody adalimumab, which neutralizes pro-inflammatory processes caused by over-production of TNF-α in vivo, and is used to treat severe symptoms of rheumatoid arthritis. The selected peptide was synthesized in monomeric and branched form and analyzed for binding to TNF-α and competition with adalimumab and TNF-α receptors. Results of competition with TNF-α receptors in surface plasmon resonance and melanoma cells expressing both TNF receptors make the peptide a candidate compound for the development of a novel anti-TNF-α drug
Classification of current anticancer immunotherapies
During the past decades, anticancer immunotherapy has evolved from a promising
therapeutic option to a robust clinical reality. Many immunotherapeutic regimens are
now approved by the US Food and Drug Administration and the European Medicines
Agency for use in cancer patients, and many others are being investigated as standalone
therapeutic interventions or combined with conventional treatments in clinical
studies. Immunotherapies may be subdivided into “passive” and “active” based on
their ability to engage the host immune system against cancer. Since the anticancer
activity of most passive immunotherapeutics (including tumor-targeting monoclonal
antibodies) also relies on the host immune system, this classification does not properly
reflect the complexity of the drug-host-tumor interaction. Alternatively, anticancer
immunotherapeutics can be classified according to their antigen specificity. While some
immunotherapies specifically target one (or a few) defined tumor-associated antigen(s),
others operate in a relatively non-specific manner and boost natural or therapy-elicited
anticancer immune responses of unknown and often broad specificity. Here, we propose
a critical, integrated classification of anticancer immunotherapies and discuss the clinical
relevance of these approaches
A new simplified calcifying solution to synthesize calcium phosphate coatings
In this work we set up new experimental conditions to deposit biomimetic coatings of different calcium
phosphates onto titanium (Ti) substrates using over-simplified, economically convenient, slightly supersaturated
solutions. The new supersaturated solutions, CaPPs, contain just calcium chloride and phosphate buffer,
without addition of further salts and organic buffers usually employed for biomimetic coatings. The product
precipitated at pH 7.2 and 37 \ub0C was constituted of spherical aggregates of poorly crystalline hydroxyapatite
(HA), similar to that obtained using HEPES as buffer system. Reduction of starting pH, which was varied from
7.2 to 6.6, promoted the precipitation of the kinetically favored phase, octacalcium phosphate (OCP), together
with HA. Furthermore, OCP could be obtained as a single phase by increasing the Ca/P molar ratio of the calcifying
solution from 1/1 to 2/1. Temperature reduction from 37 \ub0C to 25 \ub0C promoted the co-precipitation of
calcium monohydrogen phosphate dihydrate (DCPD) together with HA and OCP, in agreement with the solubility
isotherms of the different calcium phosphates. Variation of the experimental conditions was utilized
to synthesize the coatings of spherical aggregates of poorly crystalline HA, petal-like crystalline OCP, as
well as coatings containing both HA and OCP, onto titanium substrates in a few hours
Time Domain Analysis of NB-IoT Signals
The NB-IoT (NarrowBand-Internet of Things) radio technology is now widely implemented by mobile phone network operators to support the communication of IoT devices such as smart meters, insurance black boxes for cars, network connected waste bins, smart bicycles. In the present work, some LTE800 cells of different mobile phone network operators implementing the NB-IoT technology in the guard band mode have been investigated. The signals, consisting of a PRB (Physical Resource Block) 180 kHz wide, have been analyzed and characterized in the time domain by means of a narrow band instrumental chain equipped with a Rohde & Schwarz FSH8 spectrum analyzer. Time domain analysis allows us to identify, within the transmission frame, the position of the NB-IoT signaling channels such as the Narrowband Reference Signal (NRS), the primary (NPSS) and secondary (NSSS) synchronization signals and the broadcast channel (NPBCH), but, above all, to measure the power received during the transmission of the NRS. This value has been compared with that measured by the NB-IoT decoding module supplied on the same analyzer, in order to verify the equivalence of these measurement methods. This would allow use of a more diffuse and cheaper instrumentation rather than more expensive vector analyzers, currently required to assess electric fields due to the NB-IoT signals through the extrapolation techniques set by Italian CEI 211-7/E technical standard
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