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Surface coatings prepared by layer‐by‐layer technique permit loading of growth factors (GFs) and their spatially controlled release. Here, native chondroitin sulfate (nCS), oxidized CS (oCS100), or mixture of both (oCS50) are combined with collagen I (Col I) to fabricate polyelectrolyte multilayers (PEMs) that exhibit structural, mechanical, and biochemical cues like the natural extracellular‐matrix. The use of oCS enables intrinsic cross‐linking of PEM that offers higher stability, stiffness, and better control of bone morphogenetic protein‐2 (BMP‐2) release compared to nCS. oCS100 PEMs have enhanced stiffness, promote Col I fibrillization, and present BMP‐2 in a matrix‐bound manner. oCS50 PEMs show intermediate effects on osteogenesis, soft surface, high water content but also moderately slow BMP‐2 release profile. C2C12 myoblasts used for osteogenesis studies show that oCS PEMs are more stable and superior to nCS PEMs in supporting cell adhesion and spreading as well as in presenting BMP‐2 to the cells. oCS PEMs are triggering more osteogenesis as proved by the quantitative real‐time polymerase chain reaction, immune and histochemical staining. These findings show that intrinsic cross‐linking in oCS/Col I multilayers provides a successful tool to control GFs delivery and subsequent cell differentiation which opens new opportunities in regenerative therapies of bone and other tissues. [ABSTRACT FROM AUTHOR]

Background: Prevention of inadvertent hypothermia is recommended for procedures >30 minutes because hypothermia increases the risk of myocardial ischemia, intraoperative blood loss, transfusion and wound complications. Therefore, short warming interruptions between pre-warming and intraoperative warming might result in lower hypothermia rates. The aim of this retrospective investigation was to determine whether the incidence of inadvertent intraoperative hypothermia was affected by the warming interruption.Methods: The lowest intraoperative body core temperature value and the warming interruption time were taken from anaesthesia records. Body core temperature was recorded continuously, and a patient was classified to be hypothermic if the lowest recorded temperature value was <36°C. Hypothermia rates and the correlation between warming interruption times and intraoperative hypothermia rates were calculated.Results: Five thousand eighty-four patients were analysed. The intraoperative hypothermia rate was 15.3%. Nineteen patients (0.4%) had a recorded temperature of <35.0°C. An increase in forced-air warming interruption time was significantly associated with an increase in intraoperative hypothermia rates (P < .0001). Patients with interruptions in forced-air warming >20 minutes showed significantly higher hypothermia rates than those with interruptions of ≤20 minutes (P < .0001).Conclusion: Intraoperative hypothermia rates increased significantly with longer forced-air warming interruptions between pre-warming and intraoperative warming. Short warming interruptions can preserve the effect of pre-warming and are associated with low intraoperative hypothermia rates. [ABSTRACT FROM AUTHOR]

Summary: To avoid pathogen‐associated molecular pattern recognition, the hemibiotrophic maize pathogen Colletotrichum graminicola secretes proteins mediating the establishment of biotrophy. Targeted deletion of 26 individual candidate genes and seven gene clusters comprising 32 genes of C. graminicola identified a pathogenicity cluster (CLU5) of five co‐linear genes, all of which, with the exception of CLU5b, encode secreted proteins. Targeted deletion of all genes of CLU5 revealed that CLU5a and CLU5d are required for full appressorial penetration competence, with virulence deficiencies independent of the host genotype and organ inoculated. Cytorrhysis experiments and microscopy showed that Δclu5a mutants form pressurized appressoria, but they are hampered in forming penetration pores and fail to differentiate a penetration peg. Whereas Δclu5d mutants elicited WT‐like papillae, albeit at increased frequencies, papillae induced by Δclu5a mutants were much smaller than those elicited by the WT. Synteny of CLU5 is not only conserved in Colletotrichum spp. but also in additional species of Sordariomycetes including insect pathogens and saprophytes suggesting importance of CLU5 for fungal biology. Since CLU5a and CLU5d also occur in non‐pathogenic fungi and since they are expressed prior to plant invasion and even in vegetative hyphae, the encoded proteins probably do not act primarily as effectors. [ABSTRACT FROM AUTHOR]

The stability of nonpatterned and nanopatterned strong polyelectrolyte brushes (PEBs) is studied as a function of both brush character and the properties of a contacting liquid. High‐molecular‐weight PEBs of poly(4‐methyl vinylpyridinium iodide) (PMeVP) are synthesized using surface‐initiated radical‐chain polymerization. Nanopatterned brushes (NPBs) line with pattern sizes ranging from 50 to 200 nm are generated by patterning the initiator layer using deep‐ultraviolet photolithography followed by brush growth initiated from the patterned layer. Homogeneous PEBs with different degrees of charging and grafting densities are exposed to water and salt solutions with different temperatures for different periods. The degradation is monitored through dry‐state ellipsometry and atomic force microscopy measurements. Enhanced degrafting for more strongly swollen polymer brushes can be observed in agreement with an "entropic spring" model. Based on the results of the nonpatterned brushes, the NPBs are exposed to water at different temperatures and external salt content for varying periods of time. Counterintuitively, the NPBs show increased degrafting for smaller patterns, which is attributed to different polymer chain dynamics for nanobrushes and microbrushes. We investigate the influence of thermodynamic and kinetic parameters on the stability of (nanopatterned) PEBs and discuss the role of entanglements and formation of complexes in such films. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1283–1295 [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Collagen membranes are not limited to be occlusive barriers as they actively support bone regeneration. However, the impact of bone‐derived growth factors on their osteoconductive competence has not been examined. Methods: Twenty adult Sprague Dawley rats were included in the study. Calvaria defects with a diameter of five millimeter were created. The defect was covered with one layer of a collagen membrane previously soaked in conditioned medium of porcine bone chips or in culture medium alone. After 4 weeks, microcomputed tomography was performed. Undecalcified thin‐ground sections were subjected to light and scanning electron microscopy. Primary outcome parameter was the bone volume in the defect. Unit of analysis was the bone‐conditioned medium (BCM). Results: In the central defect area of the control and the BCM group, median new bone connected to the host bone was 0.54 and 0.32 mm³, respectively (p = .10). In the ectocranial defect area, the control group showed significantly more bone than the BCM group (0.90 and 0.26 mm³; p = .02). Based on an exploratory interpretation, the control group had smaller bony islands than the BCM group. Scanning electron microscopy and histology indicate the formation of bone but also the collagen membrane to be mineralized in the defect site. Conclusions: These results demonstrate that the commercial collagen membrane holds an osteoconductive competence in a rat calvaria defect model. Soaking collagen membranes with BCM shifts bone formation toward the formation of bony islands rather than new bone connected to the host bone. [ABSTRACT FROM AUTHOR]

High retention forces are the basic requirements on stretch films for agricultural or pallet wrapping of goods and significantly influenced by cling properties (autohesion) that are essential for a reliable load stability during transportation and storage. Low molecular weight polyisobutylene (PIB) has tacky properties and is immiscible with polyethylene. Blended with ethylene/α-olefin copolymers in coextruded stretch films, PIB can migrate to the film surfaces and cause cling properties. Cling and adhesion forces were investigated using the mechanical cling test, atomic force, and scanning electron microscopy and infrared spectroscopy. The molecular weight of the PIB as well as density and crystallinity of the matrix material have strong influences on migration kinetics and therefore, on the cling forces. Cling forces increase with increasing aging time, having a maximum after 2 weeks of production. The following slight decrease of the cling force might be correlated with a beginning degradation process of the UV sensitive PIB. Polyisobutylene with higher molecular weight diffuses slower through a linear low density polyethylene (LLDPE) matrix than lower molecular weight PIB, but can cause higher cling forces on the film surfaces. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40239. [ABSTRACT FROM AUTHOR]

In the last two decades it was shown that plants have a great potential for production of specific heterologous proteins. But high cost and inefficient downstream processing are a main technical bottleneck for the broader use of plant-based production technology especially for protein-based products, for technical use as fibres or biodegradable plastics and also for medical applications. High-performance fibres from recombinant spider silks are, therefore, a prominent example. Spiders developed rather different silk materials that are based on proteins. These spider silks show excellent properties in terms of elasticity and toughness. Natural spider silk proteins have a very high molecular weight, and it is precisely this property which is thought to give them their strength. Transgenic plants were generated to produce ELPylated recombinant spider silk derivatives. These fusion proteins were purified by Inverse Transition Cycling ( ITC) and enzymatically multimerized with transglutaminase in vitro. Layers produced by casting monomers and multimers were characterized using atomic force microscopy ( AFM) and AFM-based nanoindentation. The layered multimers formed by mixing lysine- and glutamine-tagged monomers were associated with the highest elastic penetration modulus. [ABSTRACT FROM AUTHOR]

Direct compounding injection molding of ternary blends of polylactide (PLA), polybutylene succinate (PBS) and a hydrogenated styrene farnesene block copolymer (HSFC) was investigated for different blend compositions. Morphological analysis by atomic force microscopy and scanning electron microscopy showed a heterogeneous morphology of the ternary blends, with coexisting droplets of HSFC and PLA respectively PBS. Particle sizes analysis of the minor phases in the ternary blends showed mean values in the range of ∼1 μm, which is discussed in correlation to the rheological properties of the blend components as obtained by high pressure capillary rheometry. In result, with increasing HSFC content, the ternary blends showed a significant increase in notched Charpy impact strength (acN). In concrete, for the ternary blends with 15 wt% of HSFC a maximum acN of 15.8 kJ/m2 was found. At the same time, incorporation of the HSFC resulted only in a moderate reduction in elastic modulus and tensile strength. [ABSTRACT FROM AUTHOR]