Investigation of the preparation method and its effect on the mechanical properties of fiber-reinforced Hydrogels

This work aims to study the mechanical properties of two kinds of hydrogels, the first is based on natural polymers derived from decellularized bovine cartilage tissue and the second is based on synthetic polymers namely polyethyleneglycole dimethacrylate. In this project, we tried on the one hand to reinforce the hydrogels using fibers and on the other hand to optimize the mechanical properties by studying the influence of the mixing parameters. The first study focused on Polyethylene glycol di-methacrylate hydrogel. We found that higher mixing time resulted in increased strength and stiffness of this hydrogel with a rate of 11%. In a second study we investigated the influence of different NFC fiber concentrations on the young modulus of decellularied extracellular matrix based hydrogels

Deciphering sources of PET signals in the tumor microenvironment of glioblastoma at cellular resolution

Various cellular sources hamper interpretation of positron emission tomography (PET) biomarkers in the tumor microenvironment (TME). We developed an approach of immunomagnetic cell sorting after in vivo radiotracer injection (scRadiotracing) with three-dimensional (3D) histology to dissect the cellular allocation of PET signals in the TME. In mice with implanted glioblastoma, translocator protein (TSPO) radiotracer uptake per tumor cell was higher compared to tumor-associated microglia/macrophages (TAMs), validated by protein levels. Translation of in vitro scRadiotracing to patients with glioma immediately after tumor resection confirmed higher single-cell TSPO tracer uptake of tumor cells compared to immune cells. Across species, cellular radiotracer uptake explained the heterogeneity of individual TSPO-PET signals. In consideration of cellular tracer uptake and cell type abundance, tumor cells were the main contributor to TSPO enrichment in glioblastoma;however, proteomics identified potential PET targets highly specific for TAMs. Combining cellular tracer uptake measures with 3D histology facilitates precise allocation of PET signals and serves to validate emerging novel TAM-specific radioligands

3D Printing of Polymers with Hierarchical Continuous Porosity

Cellular thermoplastic structures with multiscale porosity (1–300 µm microporosity to 0.3–10 mm macroporosity) are produced from an integrated approach of 3D printing by Fused Deposition Modeling printing and Supercritical CO2 Foaming. Porous strands and related hierarchical structures are processed in one continuous step. Influence of printing parameters (e.g., deposition temperature and speed) on foam porosity and pores distribution is described for a semicrystalline food grade Poly-Lactide Acid. The process is then applied to other thermoplastics filament with different mechanical properties. In particular, a composite blend of Poly-l-Lactide and βTCP (90–10) ceramic particles and a soft copolymer Poly-Lactide-co-Caprolactone are processed to print foamed strands with various internal cellular microstructures. The dynamic material transformation phenomena controlling the microstructure upon deposition and foaming are determined. This new additive manufacturing method introduces for the first time the possibility to tune cellular morphology in situ and on line, offering an unmatched freedom to design anisotropy in 3D

Late presentation of chronic viral hepatitis for medical care: a consensus definition

Abstract Introduction We present two consensus definitions of advanced and late stage liver disease being used as epidemiological tools. These definitions can be applied to assess the morbidity caused by liver diseases in different health care systems. We focus is on hepatitis B and C virus infections, because effective and well tolerated treatments for both of these infections have greatly improved our ability to successfully treat and prevent advanced and late stage disease, especially if diagnosed early. A consensus definition of late presentation with viral hepatitis is important to create a homogenous, easy-to-use reference for public health authorities in Europe and elsewhere to better assess the clinical situation on a population basis. Methods A working group including viral hepatitis experts from the European Association for the Study of the Liver, experts from the HIV in Europe Initiative, and relevant stakeholders including patient advocacy groups, health policy-makers, international health organisations and surveillance experts, met in 2014 and 2015 to develop a draft consensus definition of late presentation with viral hepatitis for medical care. This was refined through subsequent consultations among the group. Results Two definitions were agreed upon. Presentation with advanced liver disease caused by chronic viral hepatitis for medical care is defined as a patient with chronic hepatitis B and C and significant fibrosis (≥ F3 assessed by either APRI score > 1.5, FIB-4 > 3.25, Fibrotest > 0.59 or alternatively transient elastography (FibroScan) > 9.5 kPa or liver biopsy ≥ METAVIR stage F3) with no previous antiviral treatment. Late stage liver disease caused by chronic viral hepatitis is clinically defined by the presence of decompensated cirrhosis (at least one symptom of the following: jaundice, hepatic encephalopathy, clinically detectable ascites, variceal bleeding) and/or hepatocellular carcinoma. Conclusion These consensus definitions will help to improve epidemiological understanding of viral hepatitis and possibly other liver diseases, as well as testing policies and strategies