Binder and Interphase Microstructure in a Composite Material Characterized by Scanning Electron Microscopy and NMR Spin Diffusion Experiments

¹H NMR spin diffusion is shown to advantageously complement scanning electron microscopy (SEM) observations for the characterization of polymer structuring in composite materials. It is here demonstrated on a material containing a few percent of polymer binder and a crystalline organic/inorganic mixture as reinforcement. In SEM observations, polymer accumulations are seen. However, the polymer is also expected to fill small porosities and thin layers at the interface of particles to ensure the cohesion and the mechanical properties of the assembly. In most cases, this polymer structuring is invisible considering the resolution and contrast achieved by SEM on such material. It is thus investigated taking advantage of the two‐step decay of nuclear magnetic resonance spin diffusion curves. Average thickness values of 30 and 188 nm are estimated for the interphase and the overall polymer, respectively. Such structural information improves the knowledge of structure/property relationships and provides better understanding of material properties and making processes.     

The effect of delivering the chemokine SDF-1α in a matrix-bound manner on myogenesis

Several chemokines are important in muscle myogenesis and in the recruitment of muscle precursors during muscle regeneration. Among these, the SDF-1α chemokine (CXCL12) is a potent chemoattractant known to be involved in muscle repair. SDF-1α was loaded in polyelectrolyte multilayer films made of poly(l-lysine) and hyaluronan to be delivered locally to myoblast cells in a matrix-bound manner. The adsorbed amounts of SDF-1α were tuned over a large range from 100 ng/cm² to 5 μg/cm², depending on the initial concentration of SDF-1α in solution, its pH, and on the film crosslinking extent. Matrix-bound SDF-1α induced a striking increase in myoblast spreading, which was revealed when it was delivered from weakly crosslinked films. It also significantly enhanced cell migration in a dose-dependent manner, which again depended on its presentation by the biopolymeric film. The low-crosslinked film was the most efficient in boosting cell migration. Furthermore, matrix-bound SDF-1α also increased the expression of myogenic markers but the fusion index decreased in a dose-dependent manner with the adsorbed amount of SDF-1α. At high adsorbed amounts of SDF-1α, a large number of Troponin T-positive cells had only one nucleus. Overall, this work reveals the importance of the presentation mode of SDF-1α to emphasize its effect on myogenic processes. These films may be further used to provide insight into the role of SDF-1α presented by a biomaterial in physiological or pathological processes.     

Paraneoplastic neurological syndromes associated with renal or bladder cancer: case series and PRISMA-IPD systematic review

Journal of Neurology - The link between paraneoplastic neurological syndromes (PNS) and renal cell and bladder cancer (RCC/BC) is rare and uncertain. Our aim was to clinically evaluate, in light of...     

Gemcitabine-induced peripheral vascular disease and prolonged response in a patient with metastatic pancreatic adenocarcinoma: A case report

BACKGROUND Gemcitabine is an antimetabolite used in the treatment of pancreatic cancer. One of the side effects of gemcitabine is vascular toxicity. Here, we report the case of a patient treated with gemcitabine who had peripheral vascular disease concomitant with a prolonged antitumor response.CASE SUMMARY A 75-year-old man was diagnosed with locally recurrent pancreatic cancer. Partial response was achieved after 9 mo of gemcitabine. At the same time, the patient reported peripheral vascular d...