Single Extracellular Vesicle Analysis Performed by Imaging Flow Cytometry and Nanoparticle Tracking Analysis Evaluate the Accuracy of Urinary Extracellular Vesicle Preparation Techniques Differently

Small extracellular vesicles isolated from urine (uEVs) are increasingly recognized as potential biomarkers. Meanwhile, different uEV preparation strategies exist. Conventionally, the performance of EV preparation methods is evaluated by single particle quantification, Western blot, and electron microscopy. Recently, we introduced imaging flow cytometry (IFCM) as a next-generation single EV analysis technology. Here, we analyzed uEV samples obtained with different preparation procedures using nanoparticle tracking analysis (NTA), semiquantitative Western blot, and IFCM. IFCM analyses demonstrated that urine contains a predominant CD9⁺ sEV population, which exceeds CD63⁺ and CD81⁺ sEV populations. Furthermore, we demonstrated that the storage temperature of urine samples negatively affects the recovery of CD9⁺ sEVs. Although overall reduced, the highest CD9⁺ sEV recovery was obtained from urine samples stored at −80 °C and the lowest from those stored at −20 °C. Upon comparing the yield of the different uEV preparations, incongruencies between NTA and IFCM data became apparent. Results obtained by both NTA and IFCM were consistent with Western blot analyses for EV marker proteins; however, NTA results correlated with the amount of the impurity marker uromodulin. Despite demonstrating that the combination of ultrafiltration and size exclusion chromatography appears as a reliable uEV preparation technique, our data challenge the soundness of traditional NTA for the evaluation of different EV preparation methods.     

Untersuchungen zur Haftungsbeeinflussung von Pigmentdrucken durch UV-Laser-Behandlung

Investigations on Adhesion of Pigment Printings by UV-Laser Treatment Investigations on the influence of UV-laser treatment of polyethyleneterephthalate and polyamide fibers and foils on the adhesion properties of pigment printings are presented. It could be shown that even irradiation with low energy densities and low number of pulses applied increases binder film adhesion very efficiently. Some interpretations of the laser action upon adhesion improvement related to surface modification are presented.     

Synthesis and in vitro characterization of a poly(acrylic acid)-homocysteine conjugate

It was the aim of this study to improve our knowledge on thiolated polymers by the synthesis and in vitro characterization of a poly(acrylic acid)-homocysteine conjugate. Mediated by a carbodiimide, homocysteine was therefore covalently attached to poly(acrylic acid) via the formation of an amide bond. The isolated conjugate displayed 930 micromol +/- 83 micromol sulfur atoms per gram polymer. Of these thiol groups, 80.1% were oxidized to disulfide bonds during the coupling reaction. In aqueous solutions the conjugate was rapidly oxidized by the formation of disulfide bonds at pH 8, whereas it remained stable at pH 7 and below during the observation period of 4 hours. Due to the immobilization of thiol groups on the polymer, the mucoadhesive and cohesive properties of poly(acrylic acid) were strongly improved. Furthermore, the thiolated polymer exhibited a significantly (p < 0.05) improved permeation enhancing effect in comparison to the unmodified polymer. Because of these features the poly(acrylic acid)-homocysteine conjugate seems to represent a promising novel tool, which might be useful in particular for aqueous formulations based on thiomers.     

辉煌的文明复兴——评圣地亚哥·卡拉特拉瓦及其东方车站

圣地亚哥．卡拉特拉瓦个人简介及设计风格评述;介绍其代表作品葡萄牙里斯本东方车站,并且评价他运用新技术对建筑文明的复兴的贡献。     

Oberfl?chennahe Geothermie und ihre potenziellen Auswirkungen auf Grundwasser?kosysteme

The use of shallow geothermal energy is a thriving technology. Still, its impact on the ecology of subsurface habitats has not been adequately investigated. Biological processes are substantially influenced by temperature. In field and laboratory investigations comprising a temperature range from 2 to 45?°C we show, that the diversity and structure of aquifer microbial communities is significantly influenced by temperature. Microbial biomass and activities are shown to additionally depend on the availability of nutrients and substrates in the groundwater. Selected groundwater invertebrates exhibited little tolerance towards mid- and long-term exposure to increased temperatures. Our results allow first recommendations towards the design, authorization, construction and operation of shallow geothermal energy facilities in an ecologically sustainable way.     

Characterization of the Gene Cluster CYP264B1‐geoA from Sorangium cellulosum So ce56: Biosynthesis of (+)‐Eremophilene and Its Hydroxylation

Terpenoids can be found in almost all forms of life; however, the biosynthesis of bacterial terpenoids has not been intensively studied. This study reports the identification and functional characterization of the gene cluster CYP264B1–geoA from Sorangium cellulosum So ce56. Expression of the enzymes and synthesis of their products for NMR analysis and X‐ray diffraction were carried out by employing an Escherichia coli whole‐cell conversion system that provides the geoA substrate farnesyl pyrophosphate through simultaneous overexpression of the mevalonate pathway genes. The geoA product was identified as a novel sesquiterpene, and assigned NMR signals unambiguously proved that geoA is an (+)‐eremophilene synthase. The very tight binding of (+)‐eremophilene (～0.40 μM ), which is also available in S. cellulosum So ce56, and its oxidation by CYP264B1 suggest that the CYP264B1–geoA gene cluster is required for the biosynthesis of (+)‐eremophilene derivatives.     

Comparative Anti-Inflammatory Effects of Salix Cortex Extracts and Acetylsalicylic Acid in SARS-CoV-2 Peptide and LPS-Activated Human In Vitro Systems

The usefulness of anti-inflammatory drugs as an adjunct therapy to improve outcomes in COVID-19 patients is intensely discussed in this paper. Willow bark (Salix cortex) has been used for centuries to relieve pain, inflammation, and fever. Its main active ingredient, salicin, is metabolized in the human body into salicylic acid, the precursor of the commonly used pain drug acetylsalicylic acid (ASA). Here, we report on the in vitro anti-inflammatory efficacy of two methanolic Salix extracts, standardized to phenolic compounds, in comparison to ASA in the context of a SARS-CoV-2 peptide challenge. Using SARS-CoV-2 peptide/IL-1β- or LPS-activated human PBMCs and an inflammatory intestinal Caco-2/HT29-MTX co-culture, Salix extracts, and ASA concentration-dependently suppressed prostaglandin E2 (PGE₂), a principal mediator of inflammation. The inhibition of COX-2 enzyme activity, but not protein expression was observed for ASA and one Salix extract. In activated PBMCs, the suppression of relevant cytokines (i.e., IL-6, IL-1β, and IL-10) was seen for both Salix extracts. The anti-inflammatory capacity of Salix extracts was still retained after transepithelial passage and liver cell metabolism in an advanced co-culture model system consisting of intestinal Caco-2/HT29-MTX cells and differentiated hepatocyte-like HepaRG cells. Taken together, our in vitro data suggest that Salix extracts might present an additional anti-inflammatory treatment option in the context of SARS-CoV-2 peptides challenge; however, more confirmatory data are needed.     

Preventing Antibiotic-Resistant Infections: Additively Manufactured Porous Ti6Al4V Biofunctionalized with Ag and Fe Nanoparticles

Implant-associated infections are highly challenging to treat, particularly with the emergence of multidrug-resistant microbials. Effective preventive action is desired to be at the implant site. Surface biofunctionalization of implants through Ag-doping has demonstrated potent antibacterial results. However, it may adversely affect bone regeneration at high doses. Benefiting from the potential synergistic effects, combining Ag with other antibacterial agents can substantially decrease the required Ag concentration. To date, no study has been performed on immobilizing both Ag and Fe nanoparticles (NPs) on the surface of additively manufactured porous titanium. We additively manufactured porous titanium and biofunctionalized its surface with plasma electrolytic oxidation using a Ca/P-based electrolyte containing Fe NPs, Ag NPs, and the combinations. The specimen’s surface morphology featured porous TiO₂ bearing Ag and Fe NPs. During immersion, Ag and Fe ions were released for up to 28 days. Antibacterial assays against methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa showed that the specimens containing Ag NPs and Ag/Fe NPs exhibit bactericidal activity. The Ag and Fe NPs worked synergistically, even when Ag was reduced by up to three times. The biofunctionalized scaffold reduced Ag and Fe NPs, improving preosteoblasts proliferation and Ca-sensing receptor activation. In conclusion, surface biofunctionalization of porous titanium with Ag and Fe NPs is a promising strategy to prevent implant-associated infections and allow bone regeneration and, therefore, should be developed for clinical application.