UV-resistant amorphous fluorinated coating for anodized titanium surfaces

In this work, a high molecular weight copolymer of tetrafluoroethylene and perfluoro-4-trifluoromethoxy-1,3-dioxole (HYFLON^® AD60) and two perfluoropolyethers (PFPEs) containing ammonium phosphate or triethoxysilane functionalities, FLUOROLINK^® F10 and FLUOROLINK^® S10 respectively, have been evaluated as protective coatings that can be easily applied on anodized titanium surfaces. Water and n-dodecane contact angle measurements have been recorded by using the sessile drop method for bare and coated surfaces in order to determine the hydrophobic and oleophobic properties of the coatings. The UV-stability of coatings have been studied by Fourier transform infrared spectroscopy (FT-IR) analyses and by observing the variation of water contact angles on coated substrates before and after UV irradiation at regular time intervals. The thickness of the fluorinated films has been measured by ellipsometry and by weight evaluation. Preliminary tests of the adhesion between films and substrate have been conducted.     

Myositis/Myasthenia after Pembrolizumab in a Bladder Cancer Patient with an Autoimmunity-Associated HLA: Immune–Biological Evaluation and Case Report

Pembrolizumab (mAb to PD-1) has been recently approved for the therapy of pretreated urothelial cancer. Despite the efficacy, it is often accompanied by unpredictable and sometime severe immune-related (ir) adverse events (AEs). Here, we report the clinical and immune–biological characterization of a patient with a metastatic bladder cancer who developed myositis signs (M) and a myasthenia-like syndrome (MLS) during treatment with pembrolizumab. The patient presented an autoimmunity-associated HLA haplotype (HLA-A*02/HLA-B*08/HLA-C*07/HLA-DRB1*03) and experienced an increase in activated CD8 T-cells along the treatment. The symptomatology regressed after pembrolizumab discontinuation and a pyridostigmine and steroids-based therapy. This is the first report of concurrent M and MLS appearance in cancer patients receiving pembrolizumab. More efforts are needed to define early the risk and the clinical meaning of irAEs in this setting.     

Combination of Polymer Technology and Carbon Nanotube Array for the Development of an Effective Drug Delivery System at Cellular Level

In this article, a carbon nanotube (CNT) array-based system combined with a polymer thin film is proposed as an effective drug release device directly at cellular level. The polymeric film embedded in the CNT array is described and characterized in terms of release kinetics, while in vitro assays on PC12 cell line have been performed in order to assess the efficiency and functionality of the entrapped agent (neural growth factor, NGF). PC12 cell differentiation, following incubation on the CNT array embedding the alginate delivery film, demonstrated the effectiveness of the proposed solution. The achieved results indicate that polymeric technology could be efficiently embedded in CNT array acting as drug delivery system at cellular level. The implication of this study opens several perspectives in particular in the field of neurointerfaces, combining several functions into a single platform.     

Bicompartmental device for dynamic cell coculture: design, realisation and preliminary results

Low-shear perfusion and compartmental systems are very important conceptual designs for the realization of high-density cell cultures and cocultures, thus allowing very realistic models and therefore reliable results. In this work, we combines low-shear perfusion and multi-compartments in one device. We also describe the design, fabrication and validation of a bicompartmental, low-perfusion culture chamber specifically designed for applications in various fields, such as tissue engineering, pharmacology, molecular biology, pharmacokinetics, nanomedicine, and drug delivery testing. The device properties in terms of flow features and metabolite exchange capabilities are fully characterized. In vitro tests performed on cell lines confirm the effectiveness of the device as an experimental tool for measurements in dynamic and multiple-cell cultures and cocultures.     

Lagrangian formulation of a linear microstrip resonator: theory andexperiment

A Lagrangian approach is used to formulate the electromagnetic scattering properties of a linear microstrip resonator. The resonator design includes a center microstrip separated from the source and output loads by dielectric gaps. The gaps of the resonator are represented by capacitively coupled π-networks whereas the Lagrangian is formulated in the discrete limit such that the equations of motion transform into two boundary conditions, relating the waves on the two sides of the gap in terms of two lumped capacitors. The effective capacitors expressed in the boundary conditions are actually the capacitances experienced by the even and odd excitation modes of the system, respectively. The calculations, therefore take into account the characteristic impedance, effective dielectric constant, conductivity of the metal strip and the ground plane, and dielectric loss tangent of the dielectric material. In addition, the two capacitor values representing the gaps are included in a consistent manner with the above parameters by the application of the Lagrangian formulation. Calculated and measured reflection coefficients of linear microstrip resonators are compared, and general agreement is found between theory and experiments     

Radiation frequencies of ferrite patch antennas

The radiation frequencies of rectangular microstrip patch antenna deposited on ferrite substrate have been measured. Two different radiation modes were found whose frequencies behaved differently under the application of a biasing magnetic field. These two modes of radiation have been identified with a transverse mode whose radiation frequency increased with increasing magnetic field and a longitudinal mode whose radiation frequency decreased with the applied magnetic field. A theoretical model has been formulated for radiation of these two modes based on a multidomain configuration of the ferrite substrate.<>     

Retention of virulence in viable but non-culturable halophilic Vibrio spp

The viable but non-culturable (VBNC) forms of two environmental strains of Vibrio alginolyticus 1 and Vibrio parahaemolyticus 66 and one strain of V. parahaemolyticus ATCC 43996 showing virulence characteristics (hemolysin production, adhesive and/or cytotoxic ability, in vivo enteropathogenicity) were obtained by culturing bacteria in a microcosm consisting of artificial sea water (ASW) and incubating at 5 degrees C with shaking. Every 2 days, culturability of the cells in the microcosm was monitored by spread plates on BHI agar and total count and the percentage of viable cells were determined by double staining with DAPI and CTC. When cell growth was not detectable (<0.1 CFU/ml), the population was considered non-culturable and, then, the VBNC forms were resuscitated in a murine model. For each strain, eight male Balb/C mice were intragastrically inoculated with 0.1 ml of concentrated ASW bacterial culture. Two mice from each group were sacrificed at 2, 4, 8, and 12 days after challenge for autopsy and re-isolation of the microorganisms from the intestinal tissue cultures. Isolation was obtained in 25% of the animals challenged with the VBNC V. alginolyticus strain, in 37.5% of those challenged with the VBNC V. parahaemolyticus strain of environmental origin and in 50% of the animals infected with VBNC V. parahaemolyticus ATCC 43996. The strains thus isolated were again subjected to biological assays to determine the retention of pathogenicity. The virulence characteristics that seemed to disappear after resuscitation in the mouse were subsequently reactivated by means of two consecutive passages of the strains in the rat ileal loop model. The results obtained indicate that VBNC forms of the strains examined can be resuscitated and retain their virulence properties.     

Mechanical behavior of quenched isotactic polypropylene crystallized by thermal and solvent treatments

Films of quenched isotactic polypropylene were either annealed at 80, 90, 100, 110°C for 30 min or kept in different liquids for 24 h at 25°C. The liquids were cyclohexane, chloroform, and carbon tetrachloride. Both treatments induce crystallization of quenched films and the development of crystallinity was detected by carrying out density and wide-angle x-ray scattering measurements. Small-angle light scattering experiments, performed on the starting and on the crystallized samples, show that in the zones in which spherulites are present the basic gross morphology does not change after the treatments, although the increase of crystallinity is substantial for all the samples. The analysis of the mechanical behavior also indicates the absence of relevant morphological changes following the different treatments. On the other hand the increased crystallinity strongly influences the complex structural and molecular rearrangement characterizing the transition from the spherulitic to the fiber morphology. The results are discussed in terms of the great significance that structural modifications have on the physical properties.     

Crystallinity of isotactic polypropylene films annealed from the quenched state

Quenched isotactic polypropylene films were annealed at 130, 140 and 155 °C for 24 h. The structural organization, after annealing, was analysed by wide-angle X-ray diffractograms (WAXD), differential scanning calorimetry (DSC), density and sorption of dichloromethane vapour at low activity. The comparison of the different methods used to obtain the crystallinity shows that, even at the highest annealing temperature, the transformation of the smectic phase into the monoclinic phase, is not complete. WAXD and DSC give the amount of monoclinic phase, whereas the amorphous fraction was derived from sorption of dichloromethane vapour at low activity. From the density, it was possible to derive the residual smectic fraction in the different samples. The results indicate that, at temperatures higher than 150 °C, there is an accelerated decrease of smectic phase and an accelerated increase in the crystal dimensions and perfection.     

Amplification factor of echo signals in ferrimagnetic materials

It is known that spin echoes in ferrimagnetic materials can only be excited on the application of high-power microwave signals. The amplification factor of spin echoes is calculated for ferrimagnetic materials; long-range dipolar field, external RF-field couplings, and magnetization relaxations are included in the calculations. The inclusion of such interactions provides a mechanism by which realistic amplification of echoes may be calculable. The theoretical estimate of amplification is in reasonable agreement with previous experiments. Thus, the effects of carrier frequency, field gradient, and microwave power on echo amplification are calculated