Modulating endothelial adhesion and migration impacts stem cell therapies efficacy

Background: Limited knowledge of stem cell therapies‘ mechanisms of action hampers their sustainable implementation into the clinic. Specifically, the interactions of transplanted stem cells with the host vasculature and its implications for their therapeutic efficacy are not elucidated. We tested whether adhesion receptors and chemokine receptors on stem cells can be functionally modulated, and consequently if such modulation may substantially affect therapeutically relevant stem cell interactions with the host endothelium. Methods: We investigated the effects of cationic molecule polyethylenimine (PEI) treatment with or without nanoparticles on the functions of adhesion receptors and chemokine receptors of human bone marrow-derived Mesenchymal Stem Cells (MSC). Analyses included MSC functions in vitro, as well as homing and therapeutic efficacy in rodent models of central nervous system´s pathologies in vivo. Findings: PEI treatment did not affect viability, immunomodulation or differentiation potential of MSC, but increased the CCR4 expression and functionally blocked their adhesion receptors, thus decreasing their adhesion capacity in vitro. Intravenously applied in a rat model of brain injury, the homing rate of PEI-MSC in the brain was highly increased with decreased numbers of adherent PEI-MSC in the lung vasculature. Moreover, in comparison to untreated MSC, PEI-MSC featured increased tumour directed migration in a mouse glioblastoma model, and superior therapeutic efficacy in a murine model of stroke. Interpretation: Balanced stem cell adhesion and migration in different parts of the vasculature and tissues together with the local microenvironment impacts their therapeutic efficacy. Funding: Robert Bosch Stiftung, IZEPHA grant, EU grant 7 FP Healt

Molecular networks of human muscle adaptation to exercise and age

Physical activity and molecular ageing presumably interact to precipitate musculoskeletal decline in humans with age. Herein, we have delineated molecular networks for these two major components of sarcopenic risk using multiple independent clinical cohorts. We generated genome-wide transcript profiles from individuals (n = 44) who then undertook 20 weeks of supervised resistance-exercise training (RET). Expectedly, our subjects exhibited a marked range of hypertrophic responses (3% to +28%), and when applying Ingenuity Pathway Analysis (IPA) up-stream analysis to ~580 genes that co-varied with gain in lean mass, we identified rapamycin (mTOR) signaling associating with growth (P = 1.4×10−30). Paradoxically, those displaying most hypertrophy exhibited an inhibited mTOR activation signature, including the striking down-regulation of 70 rRNAs. Differential analysis found networks mimicking developmental processes (activated all-trans-retinoic acid (ATRA, Z-score = 4.5; P = 6×10−13) and inhibited aryl-hydrocarbon receptor signaling (AhR, Z-score = −2.3; P = 3×10−7)) with RET. Intriguingly, as ATRA and AhR gene-sets were also a feature of endurance exercise training (EET), they appear to represent “generic” physical activity responsive gene-networks. For age, we found that differential gene-expression methods do not produce consistent molecular differences between young versus old individuals. Instead, utilizing two independent cohorts (n = 45 and n = 52), with a continuum of subject ages (18–78 y), the first reproducible set of age-related transcripts in human muscle was identified. This analysis identified ~500 genes highly enriched in post-transcriptional processes (P = 1×10−6) and with negligible links to the aforementioned generic exercise regulated gene-sets and some overlap with ribosomal genes. The RNA signatures from multiple compounds all targeting serotonin, DNA topoisomerase antagonism, and RXR activation were significantly related to the muscle age-related genes. Finally, a number of specific chromosomal loci, including 1q12 and 13q21, contributed by more than chance to the age-related gene list (P = 0.01–0.005), implying possible epigenetic events. We conclude that human muscle age-related molecular processes appear distinct from the processes regulated by those of physical activity

Comparison of Physical Properties of Untreated and Heat Treated Beech and Hornbeam

Istraživanjem fizikalnih svojstava toplinski obrađene bukovine i grabovine utvrđeno je da je njihova srednja vrijednost manja i signifikantno se razlikuje od srednjih vrijednosti fizikalnih svojstava neobrađene bukovine i grabovine. Srednja vrijednost gustoće u apsolutno suhom stanju toplinski obrađene bukovine manja je za 8,5 % od neobrađene, a za grabovinu je ona manja za 7,5 %. Smanjenje srednjih vrijednosti maksimalnih utezanja toplinski obrađene bukovine i grabovine u odnosu prema neobrađenoj još je veće. Maksimalno radijalno utezanje toplinski obrađene bukovine manje je za 7 %, maksimalno tangencijalno utezanje za 23,5 %, a maksimalno volumno utezanje za 19,3 % od istih fizikalnih svojstava neobrađene bukovine. Toplinski obrađena grabovina ima srednju vrijednost maksimalnoga radijalnog utezanja za 123 %, maksimalnoga tangencijalnog utezanja za 86 % i maksimalnoga volumnog utezanja za 99,5 % manju od istih fizikalnih svojstava neobrađene grabovine. Takvim smanjenjem maksimalnih utezanja u radijalnome i tangencijalnom smjeru toplinskom obradom grabovina postaje znatno prihvatljivija za izradu proizvoda za koje je važna dimenzionalna stabilnost.The investigation of physical properties of heat treated beech wood and hornbeam wood found that their average value is lower and significantly different from average values of physical properties of untreated beech wood and hornbeam wood. The average value of density in absolutely dry condition of heat treated beech wood is smaller by 8.5% from the untreated, and the hornbeam wood is smaller by 7.5%. Reduction of average values of maximum shrinkage of heat treated beech wood and hornbeam wood is even bigger in relation to the untreated wood. Maximum radial shrinkage of heat treated beech wood is smaller by 7%, maximum tangential shrinkage by 23.5% and maximum volumetric shrinkage by 19.3% compared to the same physical properties of untreated beech wood. Heat treated hornbeam wood has an average value of maximum radial shrinkage smaller by 123%, maximum tangential shrinkage by 86% and maximum volume shrinkage by 99.5% compared to the same physical properties of untreated hornbeam wood. With such reduction in the maximum shrinkage in radial and tangential direction using heat treatment, hornbeam becomes particulary suitable for making products where dimensional stability is important

Von Assistenzhunden und Hunden im Wolfspelz: Eine Fallbearbeitung im Bürgerlichen Recht für Fortgeschrittene

Die der Fallbearbeitung zugrunde liegenden Klausur verbindet Fragestellungen des Allgemeinen Teils des BGB mit solchen des Schuldrechts und des Sachenrechts. Schwerpunktmäßig behandelt sie Probleme im Zusammenhang mit dem Verkauf von Tieren, AGB sowie der arglistigen Täuschung in Konstellationen mit einer Stellvertetung