Novel nano-composite biomimetic biomaterial allows chondrogenic and osteogenic differentiation of bone marrow concentrate derived cells

In clinical orthopedics suitable materials that induce and restore biological functions together with the right mechanical properties are particularly needed for the regeneration of osteochondral lesions. For this purpose, the ideal scaffold should possess the right properties with respect to degradation, cell binding, cellular uptake, non-immunogenicity, mechanical strength, and flexibility. In addition, it should be easy to handle and serve as a template for chondrocyte and bone cells guiding both cartilage and bone formation. The aim of the present study was to estimate the chondrogenic and osteogenic capability of bone marrow concentrated derived cells seeded onto a novel nano-composite biomimetic material. These properties have been evaluated by means of histological, immunohistochemical and electron microscopy analyses. The data obtained demonstrated that freshly harvested cells obtained from bone marrow were able, once seeded onto the biomaterial, to differentiate either down the chondrogenic and osteogenic pathways as evaluated by the expression and production of specific matrix molecules. These findings support the use, for the repair of osteochondral lesions, of this new nano-composite biomimetic material together with bone marrow derived cells in a “one step” transplantation procedure.     

Gangrene of the penis after implantation of penile prosthesis: case reports, treatment recommendations and review of the literature

We report 3 cases of gangrene of the penis seen at our institution after penile prosthesis implantation. All 3 patients had insulin-dependent diabetes mellitus. Amputation was required in 2 patients. Aggressive debridement in conjunction with hyperbaric oxygen prevented amputation in the third patient.     

Radiation-induced crosslinking of UHMWPE in the presence of co-agents: chemical and mechanical characterisation

Radiation-induced crosslinking has been shown to have a beneficial effect on the wear resistance of ultra high molecular weight polyethylene (UHMWPE). Since we postulate that crosslinking takes place through reactions involving terminal double bonds, unsaturated additives were added to UHMWPE in this study to enhance crosslinking. UHMWPE specimens soaked in 1,7-octadiene, methylacetylene and ethylene, respectively, were irradiated with electron beam to different doses in single or multiple passages. FTIR spectroscopy was used for the chemical characterisation of the crosslinked polymer. Tensile tests were performed with all samples in order to monitor changes in the mechanical properties.Gel fraction measurements proved that crosslinking took place in all the irradiated samples, but 1,7-octadiene turned out to be the most effective additive for the present purpose, exhibiting a good efficiency in enhancing crosslinking. The FTIR analyses showed that consumption of vinyl double bonds is proportional to the irradiation dose, with an efficiency which increases with increasing their initial concentration, confirming the hypothesis of the involvement of these groups in the crosslinking process. In the case of UHMWPE with 1,7-octadiene irradiated to high doses in multiple passages, the results of the tensile tests indicated a significant decrease in both elongation at break (up to 65%) and ultimate stress (up to 25%). A possible explanation of the diminished strength of the crosslinked material has also been proposed.     

Mechanical and Microstructural Characterization of AF955 (UNS N09955) Nickel-Based Superalloy After Different Heat Treatments

The mechanical and strain-hardening behaviors of the new AF955 nickel-based superalloy were investigated through two different heat treatments. The first consisted of a solubilization with a subsequent precipitation heat treatment at 746 °C for 4 hours, while the second included an additional precipitation treatment at 621 °C for 8 hours, which further increased the AF955 yield stress by about 15 pct and the ultimate stress by about 9 pct. However, through analyzing the true stress and true strain flow curves, the Considére’s stresses of AF955 after the heat treatments were similar and the strain-hardening behaviors at high stresses were surprisingly comparable. The AF955 microstructures were observed after the two different heat treatments through transmission electron microscopy. The dimensions and volume fractions of the strengthening γ″ and γ′ particles were quantified through the imaging analysis technique, finding that there were only γ″ particles in AF955 with heat treatment at 746 °C, while with the additional heat treatment at 621 °C, there was a higher total volume fraction of the γ″?+?γ′ phases. The microstructure quantification allowed modeling of the different yield behaviors of the alloy after the heat treatments through the Orowan model for nondeformable particles and the weak coupled dislocation (WCD) and strong coupled dislocation models for deformable particles. The WCD model for deformable particles described the yield behaviors of AF955 very well after both heat treatments. Moreover, the deformability of the γ″ and γ′ particles also explained the comparable strain-hardening behaviors at high stresses of AF955 after the two different heat treatments. Although mechanical properties are correctly assumed to be key parameters for classifying materials, the analysis of true stress and true strain flow curves always should be performed to properly rationalize the mechanical behaviors of metallic alloys.     

Lectins,trypsin and α-amylase inhibitors in dietary supplements containing <Emphasis Type="Italic">Phaseolus vulgaris</Emphasis>

Some dietary supplements used to control overweight are based on protein concentrates from Phaseolus vulgaris, or kidney bean, known to contain high levels of α-amylase inhibitor, which may reduce the adsorption and prevent the digestion of carbohydrates. These concentrates of kidney bean also contain significant levels of antinutritional factors such as lectins and trypsin inhibitors. In recent years the concentrates of kidney bean have been processed to inactivate lectins and trypsin-inhibitor activity while preserving substantial α-amylase inhibitor activity. The aim of this study was to investigate and to compare the activity of the α-amylase inhibitor in some commercial supplements, and to determine the levels of residual lectins and trypsin inhibitors. The results show that the technological treatment used to reduce the levels of lectins and trypsin inhibitors partially decreases the activity of the amylase inhibitor. This study suggests the need for better standardization of the technological treatment of protein concentrates to ensure both the efficacy and safety of these dietary supplements.     

Generation and Characterization of a Tumor Stromal Microenvironment and Analysis of Its Interplay with Breast Cancer Cells: An In Vitro Model to Study Breast Cancer-Associated Fibroblast Inactivation

Breast cancer-associated fibroblasts (BCAFs), the most abundant non-cancer stromal cells of the breast tumor microenvironment (TME), dramatically sustain breast cancer (BC) progression by interacting with BC cells. BCAFs, as well as myofibroblasts, display an up regulation of activation and inflammation markers represented by α-smooth muscle actin (α-SMA) and cyclooxygenase 2 (COX-2). BCAF aggregates have been identified in the peripheral blood of metastatic BC patients. We generated an in vitro stromal model consisting of human primary BCAFs grown as monolayers or 3D cell aggregates, namely spheroids and reverted BCAFs, obtained from BCAF spheroids reverted to 2D cell adhesion growth after 216 h of 3D culture. We firstly evaluated the state of activation and inflammation and the mesenchymal status of the BCAF monolayers, BCAF spheroids and reverted BCAFs. Then, we analyzed the MCF-7 cell viability and migration following treatment with conditioned media from the different BCAF cultures. After 216 h of 3D culture, the BCAFs acquired an inactivated phenotype, associated with a significant reduction in α-SMA and COX-2 protein expression. The deactivation of the BCAF spheroids at 216 h was further confirmed by the cytostatic effect exerted by their conditioned medium on MCF-7 cells. Interestingly, the reverted BCAFs also retained a less activated phenotype as indicated by α-SMA protein expression reduction. Furthermore, the reverted BCAFs exhibited a reduced pro-tumor phenotype as indicated by the anti-migratory effect exerted by their conditioned medium on MCF-7 cells. The deactivation of BCAFs without drug treatment is possible and leads to a reduced capability of BCAFs to sustain BC progression in vitro. Consequently, this study could be a starting point to develop new therapeutic strategies targeting BCAFs and their interactions with cancer cells.     

Estimating Temporal Changes in Extreme Rainfall in Sicily Region (Italy)

An intensification of extreme rainfall events have characterized several areas of peninsular and insular Italy since the early 2000s, suggesting an upward ongoing trend likely driven by climate change. In the present study temporal changes in 1-, 3-, 6-, 12- and 24-h annual maxima rainfall series from more than 200 sites in Sicily region (Italy) are examined. A regional study is performed in order to reduce the uncertainty in change detection related to the limited length of the available records of extreme rainfall series. More specifically, annual maxima series are treated according to a regional flood index - type approach to frequency analysis, by assuming stationarity on a decadal time scale. First a cluster analysis using at-site characteristics is used to determine homogeneous rainfall regions. Then, potential changes in regional L-moment ratios are analyzed using a 10-year moving window. Furthermore, the shapes of regional growth curves, derived by splitting the records into separate decades, are compared. In addition, a jackknife procedure is used to assess uncertainty in the fitted growth curves and to identify significant trends in quantile estimates. Results reveal that L-moment ratios show a general decreasing trend and that growth curves for the last decade (2000–2009) usually do not stand above the others, with the only exception of the ones related to the outer western part of Sicily. On the other hand, rainfall quantile estimates for the same period are the highest values almost all over the region. An explanation can be found in the increase of subregional average medians, largely caused by recent severe local storms.