The cell recognition of bioactive ligands immobilized on polymeric surfaces is strongly dependent on ligand presentation at the cell/material interface. While small peptide sequences such as Arg-Gly-Asp (RGD) are being widely used to obtain biomimetic interfaces, surface characteristics after immobilization as well as presentation of such ligands to cell receptors deserve more detailed investigation. Here, we immobilized an RGD-based sequence on poly(epsilon-caprolactone) (PCL), a largely widespread polymeric material used in biomedical applications, after polymer aminolysis. The surface characteristics along with the efficacy of the functionalization was monitored by surface analysis (FTIR-ATR, contact angle measurements, surface free energy determination) and spectrophotometric assays specially adapted for the analytical quantification of functional groups and/or peptides at the interface. Particular attention was paid to the evaluation of a number, morphology, and penetration depth of immobilized functional groups and/or peptides engrafted on polymeric substrates. In particular, a typical morphology in peptide distribution was evidenced on the surface raised from polymer crystallites, while a significant penetration depth of the engrafted molecules was revealed. NIH3T3 fibroblast adhesion studies verified the correct presentation of the ligand with enhanced cell attachment after peptide conjugation. Such work proposes a morphological and analytical approach in surface characterization to study the surface treatment and the distribution of ligands immobilized on polymeric substrates.

The design of porous scaffolds able to promote and guide cell proliferation, colonization, and biosynthesis in three dimensions is key determinant in bone tissue engineering (bTE). The aim of this study was to assess the role of the micro-architecture of poly(epsilon-caprolactone) scaffolds in affecting human mesenchymal stem cells' (hMSCs) spatial organization, proliferation, and osteogenic differentiation in vitro. Poly(epsilon-caprolactone) scaffolds for bTE and characterized by mono-modal and bi-modal pore size distributions were prepared by the combination of gas foaming and selective polymer extraction from co-continuous blends. The topological properties of the pore structure of the scaffolds were analyzed and the results correlated with the ability of hMSCs to proliferate, infiltrate, and differentiate in vitro in three dimensions. Results showed that the micro-architecture of the pore structure of the scaffolds plays a crucial role in defining cell seeding efficiency as well as hMSCs' three-dimensional colonization, proliferation, and osteogenic differentiation. Taken all together, our results indicated that process technologies able to allow a fine-tune of the topological properties of biodegradable porous scaffolds are essential for bTE strategies.

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Purpose In a phase II trial, SWOG S0108, patients with relapsed, aggressive non-Hodgkin lymphoma were treated with single agent bevacizumab. The primary endpoint was 6 month progression free survival (PFS) with secondary endpoints including response rate, toxicity, and laboratory correlative studies. Patients and Methods 52 patients in first or second relapse with diffuse large B-cell or mantle cell lymphoma were enrolled. 45 patients were eligible. Patients were treated with bevacizumab at 10mg/kg every 2 weeks with disease assessments every 8 weeks. Biomarkers analyzed included plasma VCAM, urine VEGF, circulating endothelial cells (CEC), and VEGF and VEGF receptor expression in lymphoma specimens. Results Therapy was well tolerated with no unexpected toxicities observed. 6 month PFS was 16% with a response rate of 2%. 11 patients had prolonged stable disease. The median duration of response or stable disease was 5.2 months (range 3.5 – 72.7). VEGF and VEGF receptor expression was observed in 70% and 65% of specimens, respectively. There was excellent concordance between expression of VEGF and VEGF receptors. Baseline urine VEGF and VCAM levels correlated with survival. CEC levels decreased in patients with elevated baseline values. Conclusion Bevacizumab, as a single agent, is well-tolerated in patients with relapsed aggressive NHL, but has little single agent activity. Laboratory correlative studies and prolonged PFS in several patients suggest the VEGF pathway may play an important role in aggressive NHL. Future trials should test the hypothesis that antiangiogenic therapies will synergize with chemotherapy regimens in improving response rates and overall survival of patients with aggressive NHL.

S0515 was a phase 2 trial to determine whether the addition of bevacizumab to cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) plus rituximab (R-CHOP) would improve progressionfree survival (PFS) without adding significant toxicity in patients with newly diagnosed advanced diffuse large B-cell lymphoma. A total of 73 patients were enrolled. For the 64 eligible patients, median age was 68 years, and 60% had International Prognostic Index scores more than or equal to 3. The observed 1-and 2-year PFS estimates were 77% and 69%, respectively. These PFS estimates were not statistically different from the expected PFS for this population if treated with R-CHOP alone. Grade 3 or higher toxicities were observed in 81% of patients, including 2 grade 5 events. The majority of serious toxicities were hematologic but also included 5 patients with gastrointestinal perforations, 4 patients with thrombotic events, and 11 patients who developed grade 2 or 3 left ventricular dysfunction. Higher baseline urine VEGF and plasma VCAM levels correlated with worse PFS and overall survival. In conclusion, the addition of bevacizumab to R-CHOP chemotherapy was not promising in terms of PFS and resulted in increased serious toxicities, especially cardiac and gastrointestinal perforations. This study is registered at www.clinical trials.gov as #NCT00121199. (Blood. 2012; 120(6):1210-1217)

SynopsisThe cure behavior of commercial grade TGDDM-DDS mixtures of compositions ranging from 1 0 10 100 phr of hardener and the thermal polymerization of the epoxy component are analyzed by means of' differential scanning calorimetry. The kinetic parameters and heats of reaction determined in isothermal and dynamic scans suggest that DDS primary amine addition and epoxide etherification dominate the cure reactions. The primary amine epoxide addition is characterized by overall heat of'reaction (referred to the weight of the epoxy component) of 255 cal/g and by an activation energy 01' 16.6 kcal/mol. The corresponding values for the etherif'ication reaction are, respectively, 170 cal/g iind 41 kcal/mol. A method of derivation of the epoxide conversion from the heat evolved in DSC thermal scans of these systems is presented. The results are in good agreement with independent IK determinations. The steady shear and oscillatory viscosity measurements and the calorimetric iinalysis of the isothermal cure a t 14OoC, 160"C, and 180°C of a TGDDM-DDS mixture containing :i5 phr of' hardener indicate that gelation is principally governed by the piimary amine addition. The gelation limits calculated in isothermal tests by combining the calorimetric analysis and the theory describing the nonlinear copolymerization of the tetrafunctional TGDDM with an essentially difunctional DDS were in good agreement with the values experimentally determined through rheological measurements.

BackgroundThe independent prognostic impact of diabetes mellitus (DM) and prediabetes mellitus (pre‐DM) on survival outcomes in patients with chronic heart failure has been investigated in observational registries and randomized, clinical trials, but the results have been often inconclusive or conflicting. We examined the independent prognostic impact of DM and pre‐DM on survival outcomes in the GISSI‐HF (Gruppo Italiano per lo Studio della Sopravvivenza nella Insufficienza Cardiaca‐Heart Failure) trial.Methods and ResultsWe assessed the risk of all‐cause death and the composite of all‐cause death or cardiovascular hospitalization over a median follow‐up period of 3.9 years among the 6935 chronic heart failure participants of the GISSI‐HF trial, who were stratified by presence of DM (n=2852), pre‐DM (n=2013), and non‐DM (n=2070) at baseline. Compared with non‐DM patients, those with DM had remarkably higher incidence rates of all‐cause death (34.5% versus 24.6%) and the composite end point (63.6% versus 54.7%). Conversely, both event rates were similar between non‐DM patients and those with pre‐DM. Cox regression analysis showed that DM, but not pre‐DM, was associated with an increased risk of all‐cause death (adjusted hazard ratio, 1.43; 95% CI, 1.28–1.60) and of the composite end point (adjusted hazard ratio, 1.23; 95% CI, 1.13–1.32), independently of established risk factors. In the DM subgroup, higher hemoglobin A1c was also independently associated with increased risk of both study outcomes (all‐cause death: adjusted hazard ratio, 1.21; 95% CI, 1.02–1.43; and composite end point: adjusted hazard ratio, 1.14; 95% CI, 1.01–1.29, respectively).ConclusionsPresence of DM was independently associated with poor long‐term survival outcomes in patients with chronic heart failure.Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00336336.

Digital Holography (DH) in microscopic configuration is a powerful tool for the imaging of micro-objects contained into a three dimensional (3D) volume, by a single-shot image acquisition. Many studies report on the ability of DH to track particle, microorganism and cells in 3D. However, very few investigations are performed with objects that change severely their morphology during the observation period. Here we study DH as a tool for 3D tracking an osteosarcoma cell line for which extensive changes in cell morphology are associated to cell motion. Due to the great unpredictable morphological change, retrieving cell's position in 3D can become a complicated issue. We investigate and discuss in this paper how the tridimensional position can be affected by the continuous change of the cells. Moreover we propose and test some strategies to afford the problems and compare it with others approaches. Finally, results on the 3D tracking and comments are reported and illustrated.