Microfabricated and multilayered PLGA structure for the development of co-cultured in vitro liver models

One of the main advantages of having an in vitro model is the possibility of reducing toxic effects of drugs on human body and evaluate their response to pharmacological treatments to improve the efficacy of a patient-specific therapy. The limitation of such in vitro model is the use of monolayer hepatocytes cultures that show some problems of protein secretion and hepatic functionality. In order to overcome these drawbacks, we present two innovative multilayer structures based on micro-stamped poly(lactic-co-glycolic acid) (PLGA) structures and hepatocytes and fibroblast co-cultures. In particular, the first model consisted of 1 up to 5 layers of PLGA seeded with the previously cited co-culture, while the second model consisted of various sandwich structures of PLGA functionalised (or not) with collagen and seeded with hepatocytes and/or fibroblasts. A mechanical analysis, contact angle and surface charge density measurements were carried out. After these preliminary tests, a metabolic analysis was performed evaluating glucose consumption and urea and albumin production over a culture period of 11 days. Results showed promising application of these in vitro liver models, in particular considering the field of cirrhotic liver treatment

Ultrafast charge carrier dynamics in quantum confined 2D perovskite

We studied the charge carrier dynamics in 2D perovskite NBT2PbI4 by ultrafast optical pump-THz probe spectroscopy. We observed a few ps long relaxation dynamics that can be ascribed to the band to band carrier recombination, in the absence of any contribution from many-body and trap assisted processes. The transient conductivity spectra show that the polaron dynamics is strongly modulated by the presence of a rich exciton population. The polarization field resulting from the exciton formation acts as the source of a restoring force that localizes polarons. This is revealed by the presence of a negative imaginary conductivity. Our results show that the dynamics of excitons in 2D perovskites at room temperature can be detected by monitoring their effect on the conductivity of the photoinduced polaronic carrier

Triphasic scaffolds for the regeneration of the bone-ligament interface

A triphasic scaffold (TPS) for the regeneration of the bone-ligament interface was fabricated combining a 3D fiber deposited polycaprolactone structure and a polylactic co-glycolic acid electrospun. The scaffold presented a gradient of physical and mechanical properties which elicited different biological responses from human mesenchymal stem cells. Biological test were performed on the whole TPS and on scaffolds comprised of each single part of the TPS, considered as the controls. The TPS showed an increase of the metabolic activity with culturing time that seemed to be an average of the controls at each time point. The importance of differentiation media for bone and ligament regeneration was further investigated. Metabolic activity analysis on the different areas of the TPS showed a similar trend after 7 days in both differentiation media. Total alkaline phosphatase (ALP) activity analysis showed a statistically higher activity of the TPS in mineralization medium compared to the controls. A different glycosaminoglycans amount between the TPS and its controls was detected, displaying a similar trend with respect to ALP activity. Results clearly indicated that the integration of electrospinning and additive manufacturing represents a promising approach for the fabrication of scaffolds for the regeneration of tissue interfaces, such as the bone-to-ligament one, because it allows mimicking the structural environment combining different biomaterials at different scales

Quantum path control in harmonic generation by temporal shaping of few-optical-cycle pulses in ionizing media

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Proteomic Modulation in TGF-β-Treated Cholangiocytes Induced by Curcumin Nanoparticles

Curcumin is a natural polyphenol that exhibits a variety of beneficial effects on health, including anti-inflammatory, antioxidant, and hepato-protective properties. Due to its poor water solubility and membrane permeability, in the present study, we prepared and characterized a water-stable, freely dispersible nanoformulation of curcumin. Although the potential of curcumin nanoformulations in the hepatic field has been studied, there are no investigations on their effect in fibrotic pathological conditions involving cholangiocytes. Exploiting an in vitro model of transforming growth factor-  (TGF- )-stimulated cholangiocytes, we applied the Sequential Window Acquisition of All Theoretical Mass Spectra (SWATH-MS)-based quantitative proteomic approaches to study the proteome modulation induced by curcumin nanoformulation. Our results confirmed the well-documented anti-inflammatory properties of this nutraceutic, highlighting the induction of programmed cell death as a mechanism to counteract the cellular damages induced by TGF- . Moreover, curcumin nanoformulation positively influenced the expression of several proteins involved in TGF- -mediated fibrosis. Given the crucial importance of deregulated cholangiocyte functions during cholangiopathies, our results provide the basis for a better understanding of the mechanisms associated with this pathology and could represent a rationale for the development of more targeted therapies

Calibration and First light of the Diabolo photometer at the Millimetre and Infrared Testa Grigia Observatory

We have designed and built a large-throughput dual channel photometer, Diabolo. This photometer is dedicated to the observation of millimetre continuum diffuse sources, and in particular, of the Sunyaev-Zel'dovich effect and of anisotropies of the 3K background. We describe the optical layout and filtering system of the instrument, which uses two bolometric detectors for simultaneous observations in two frequency channels at 1.2 and 2.1 mm. The bolometers are cooled to a working temperature of 0.1 K provided by a compact dilution cryostat. The photometric and angular responses of the instrument are measured in the laboratory. First astronomical light was detected in March 1995 at the focus of the new Millimetre and Infrared Testa Grigia Observatory (MITO) Telescope. The established sensitivity of the system is of 7 mK_RJ s^1/2$. For a typical map of at least 10 beams, with one hour of integration per beam, one can achieve the rms values of y_SZ ~ 7 10^-5 and the 3K background anisotropy Delta T/T ~ 7 10^-5, in winter conditions. We also report on a novel bolometer AC readout circuit which allows for the first time total power measurements on the sky. This technique alleviates (but does not forbid) the use of chopping with a secondary mirror. This technique and the dilution fridge concept will be used in future scan--modulated space instrument like the ESA Planck mission project.Comment: 10 pages, LaTeX, 12 figures, accepted for publication in Astronomy and Astrophysics Supplement Serie

Attosecond metrology in the few-optical-cycle regime

The polarization gating method in combination with few-optical-cycle driving pulses with controlled waveform is a powerful technique for the generation of isolated few-cycle attosecond pulses. We show that such a technique allows one to generate attosecond pulses tunable in a broad spectral region, corresponding to more than 26 eV. Complete temporal characterization of the attosecond pulses has been obtained by using the frequency resolved optical gating for complete reconstruction of attosecond bursts technique. The physical processes which determine the temporal confinement of the extreme ultraviolet radiation and the effects of various experimental parameters on the electric field of the attosecond pulses have been investigated using numerical simulations based on the nonadiabatic saddle-point method

Valorization of not soluble byproducts deriving from green keratin extraction from poultry feathers as filler for biocomposites

The valorization of poultry feathers wastes is very important to reduce the environmental pollution deriving from their disposal. In this frame, we present the production process of completely natural, biodegradable, biocompatible, and eco-friendly composites made by not soluble keratin (NSK) and poly(lactic acid) (PLA). NSK has been obtained as a byproduct of a microwave-assisted keratin extraction from poultry feathers and it has been added to PLA pellets without adding any additional compatibilizers or plasticizers, unlike from the other works reported in the literature until now. The mixture has been used to obtain homogeneous NSK-based PLA filaments by means of hot-melt extrusion technology. The filaments have been subsequently 3D printed to explore applications in the additive manufacturing field. All the samples have unaltered thermal stability, but reduced toughness with respect to neat PLA. Other tested parameters (water adsorption, glass transition, and crystallinity) are dependent on NSK content and fabrication technology. Besides, Fourier Transform Infrared Spectroscopy highlights the differences in the structure of the NSK-based PLA filaments and 3D printed samples