30 research outputs found
A Comparative Study on the Roll-to-Roll Processing of a SilicateâPolyvinyl Alcohol Composite Barrier Lacquer Using Slot-Die and Reverse Gravure Coating Techniques
The integration of platelet-shaped montmorillonite particles to improve the oxygen barrier
of polyvinyl-alcohol-based barrier layers is state-of-the-art, but research on roll-to-roll coatings of
such composite barrier lacquers has not been widely published. In this study, two different coating
techniques, slot-die and reverse gravure, were used on a roll-to-roll scale to apply barrier lacquers
comprising polyvinyl alcohol and montmorillonite. The lacquers were analyzed regarding viscosity at
certain shear rates and surface energy and the dried coating layers regarding oxygen barrier, surface
morphology, and particle orientation. Low permeability coefficients delivering a high oxygen barrier
of 0.14 and 0.12 cm3 (STP) 1ÎŒm.m2 d bar were achieved for the coating layers with slot-die and reverse gravure
coating, respectively. It turned out that the properties of the barrier lacquer need to be adjusted to
the coating technique to achieve high oxygen barrier performance. By tailoring the barrier lacquer
formulation, the orientation of the platelet-shaped montmorillonite particles can be achieved using
both techniques. A low solid content of down to 3 wt% is preferable for the premetered slot-die
coating, because it results in low agglomeration quantity in the coating layer. A high solid content of
up to 9 wt% is preferable for the self-metered reverse gravure coating to assure a homogeneously
coated layer
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Die flexible Verpackung von morgen - Anforderungen an die Veredler
Die groĂen Trends fĂŒr den Lebensmittelmarkt - Gesundheit, QualitĂ€t, Convenience und Sicherheit - bestimmen auch in Zukunft, welche Arten von Verpackungen eingesetzt werden. Die wesentliche Aufgabe ist, die kundenspezifischen Anforderungen in Zukunft noch besser mit den technischen Anforderungen in Einklang zu bringen, die das Produkt an die Verpackung stellt. Trotz der absehbar schlechteren VerfĂŒgbarkeit fossiler Ressourcen wird auch die Verpackung der Zukunft hauptsĂ€chlich aus Kunststoff bestehen. Grund dafĂŒr ist, dass sich die vielfĂ€ltigen und oft sogar miteinander kollidierenden Anforderungen am besten mit Kunststoffen realisieren lassen. Die schwierige Ertragssituation der Verpackungshersteller und der Lebensmittelproduzenten fĂŒhrt allerdings dazu, dass sich die notwendigen technischen Entwicklungen nur langsam vollziehen
Investigation of the 3-hydroxyvalerate content and degree of crystallinity of P3HB-co-3HV cast films using Raman spectroscopy
The structural properties of extruded cast films of poly-3-hydroxybutyrate (P3HB) and poly-3-hydroxybutyrate-co-3-hydroxyvalerate (P3HB-co-3HV) were analysed by Raman spectroscopy. A sensitive band for the side chain of the 3HV was found at 844 cmâ1 (ÎœCC, ÎœC-COO). Using an internal standard at 1101 cmâ1 (ÎœsC-O-C, ÏCH3), a model for calculation of the 3HV content was developed. This was based on analysis of samples with a 3HV content of 0â12 mol%. Additionally, P3HB-co-3HV samples were tempered in order to create different degrees of crystallinity. The induced changes in the Raman spectra were analysed. The Raman model to determine the degree of crystallinity considers the sensitive band at 2999 cmâ1 (ÎœasCH2) and the internal standard at 1059 cmâ1 (ÎœC-O, ÎœC-CH3, ÏCH2). The investigated crystallinity was in a range of 0.69â0.86
Environmental Microplastic Particles vs. Engineered Plastic MicroparticlesâA Comparative Review
Microplastic particles (MPs) pose a novel threat to nature. Despite being first noticed in the 1970s, research on this topic has only surged in recent years. Researchers have mainly focused on environmental plastic particles; however, studies with defined microplastic particles as the sample input are scarce. Furthermore, comparison of those studies indicates a discrepancy between the particles found (e.g., in the environment) and those used for further research (e.g., exposure studies). Obviously, it is important to use particles that resemble those found in the environment to conduct appropriate research. In this review, different categories of microplastic particles are addressed, before covering an overview of the most common separation and analysis methods for environmental MPs is covered. After showing that the particles found in the environment are mostly irregular and polydisperse, while those used in studies with plastic microparticles as samples are often not, different particle production techniques are investigated and suggestions for preparing realistic plastic particles are given