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Endothelial cells, due to their location, are interesting objects for atomic force spectroscopy study. They constitute a barrier between blood and vessel tissues located deeper, and therefore they are the first line of contact with various substances present in blood, eg, drugs or nanoparticles. This work intends to verify whether the mechanical response of immortalized human umbilical vein endothelial cells (EA.hy926), when exposed to silver nanoparticles, as measured using force spectroscopy, could be effectively used as a bio-indicator of the physiological state of the cells. Silver nanoparticles were characterized with transmission electron microscopy and dynamic light scattering techniques. Tetrazolium salt reduction test was used to determine cell viability after treatment with silver nanoparticles. An elasticity of native cells was examined in the Hanks' buffer whereas fixed cells were softly fixed with formaldehyde. Additional aspect of the work is the comparative force spectroscopy utilizing AFM probes of ball-shape and conical geometries, in order to understand what changes in cell elasticity, caused by SNPs, were detectable with each probe. As a supplement to elasticity studies, cell morphology observation by atomic force microscopy and detection of silver nanoparticles inside cells using transmission electron microscopy were also performed. Cells exposed to silver nanoparticles at the highest selected concentrations (3.6 μg/mL, 16 μg/mL) are less elastic. It may be associated with the reorganization of the cellular cytoskeleton and the "strengthening" of the cell cortex caused by presence of silver nanoparticles. This observation does not depend on cell fixation. Agglomerates of silver nanoparticles were observed on the cell membrane as well as inside the cells.

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Zusammenfassung Die Nachrechnungen bestehender, älterer Brücken erfolgt im Allgemeinen auf Grundlage der Nachrechnungsrichtlinie für bestehende Straßenbrücken. Für die Nachweise der Querkraft- und Torsionstragfähigkeit enthält die Richtlinie gegenüber dem aktuellen Regelwerk DIN EN 1992–2/NA modifizierte und erweiterte Bemessungsansätze die den Besonderheiten des Bestands Rechnung tragen. Dennoch ergeben sich häufig zum Teil starke Defizite in Bezug auf die Schubtragfähigkeit. Um in solchen Fällen den Umfang der Verstärkungsmaßnahmen zu reduzieren oder gar vorzeitige Ersatzneubauten zu vermeiden, erlaubt die Nachrechnungsrichtlinie auch die Anwendung von wissenschaftlichen ausreichend verifizierten Verfahren mit denen mögliche Tragreserven erfasst werden können, die bei stark idealisierten genormten Standardverfahren vernachlässigt werden. Das aktuelle Nachweisformat für die Querkrafttragfähigkeit basiert auf einem parallelgurtigen Fachwerk mit Rissreibung und besitzt in Abhängigkeit vom Tragsystem, Querschnitt und Belastung insbesondere bei Spannbetontragwerken zum Teil erhebliche Tragreserven. Im folgenden Beitrag wird die Anwendung des Erweiterten Druckbogenmodels als wissenschaftliches Verfahren auf ein Bauwerk vorgestellt. Das Model erfasst neben dem Fachwerktraganteil auch die Tragwirkung des Betondruckbogens, der sich infolge Vorspannung und Biegebeanspruchung als Betontraganteil einstellt.

The anti-inflammatory activity of the simvastatin is well illustrated by the endothelium cell elasticity changes returning from the characteristic inflammation time cycle "soft-stiff-soft" to control values. Furthermore, the elasticity results and F-actin labeling data indicated a preventive effect for 1- MP, whereas 1,4-DMP does not exhibit endothelium activity even at toxic concentrations.

The mitochondrial 18kDa Translocation Protein (TSPO) was first identified in 1977 by its capability to bind benzodiazepines in peripheral tissues. It is more commonly known after its previous name - peripheral benzodiazepine receptor (PBR) as opposed to the central benzodiazepine receptor (CBR), from which it differs by location, structure and function. It is ubiquitous with highest expression in steroid-producing tissues, like adrenal cortex, ovaries, testicles, and placenta. The role of TSPO is crucial for living; its inactivation results in early embryonic-lethal phenotype in mice. TSPO has been implicated in various functions of cell, including steroidogenesis, cellular respiration, reactive oxygen species production, heme biosynthesis, immunomodulation, apoptosis, and cellular proliferation. TSPO has been shown to interact with other cellular proteins: 32 kDa voltage-dependent anion channel (VDAC), 30 kDa adenine nucleotide translocase (ANT), cyclophilin D, hexokinase, creatinine kinase, diazepam binding inhibitor (DBI), phosphate carrier and Bcl-2 family. They are - involved in the formation and regulation of mitochondrial permeability transition pore (mPTP) at the junction of the inner and outer mitochondrial membranes. While the function and characteristics of the mPTP are known, its well defined, but its structure remains speculative. Changes in TSPO expression are associated with multiple disorders, including cancer, ischaemia-reperfusion injury, neurological diseases and psychiatric disorders, atheromatosis, and others. - TSPO is able to bind cholesterol, porphyrins and other ligands with different affinity. The current knowledge of TSPO implicates its potential use as a diagnostic marker and therapeutic target in different diseases and their therapies.

This paper presents the tribological properties of silicon and oxygen incorporated diamond-like carbon coatings tested in simulated body fluid and bovine serum albumin environments. The tests were performed using a ball-on-disc tribometer with an AISI316L steel counterbody. The wear tracks and wear scars were analyzed using optical microscopy and a nanoindenter. The interaction between the coating and the working environment was analyzed by Fourier transform infrared spectroscopy, whereas changes in the chemical structure before and after the tribological tests were compared with the use of Raman spectroscopy. Our study showed that the tribological parameters are governed by the presence of oxygen rather than the changing concentration of silicon. Both of the spectroscopy results confirm this statement, indicating that coatings with low concentrations of silicon and oxygen appear to be better candidates for biological applications in terms of wear resistance.

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