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Understanding of biology of osteosarcoma malignant progression is indispensable for enhancement of conventional chemotherapy by the use of silver nanoparticles (AgNPs). We presented an in vitro model of cancer progression closely resembling processes occurring in vivo in terms of protein profile. A comparison of cytotoxic and genotoxic potential of AgNPs in Saos‐2 cells in early stages of cancerous progression (early passages) with the cells in advanced stages (late passages) demonstrated significantly reduced responsiveness of the late passage cells to nanoparticles toxicity. It was also confirmed by proteome analysis as we identified considerably higher number of differentially expressed proteins in Saos‐2 cells in early passages compared to the late passage cells. Our studies showed that the ability of AgNPs as potential drug carriers to deliver a medication and/or to evoke toxic effects might be significantly diminished in advanced stages of cancer progression. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess the effect of PAMAM dendrimers of second, fourth, and seventh generations on human umbilical vein endothelial cells. Primary endothelial cells were exposed to PAMAM dendrimers for 24 h, using concentrations reducing cellular viability to the levels of 90, 75, and 50%. We assumed, that changes in mechanical properties reflect toxicity of PAMAM dendrimers. The mechanical properties were investigated using atomic force spectroscopy (AFS) technique with the use of two approaches for measuring cell elasticity: global, where the tests were performed using a micrometer-hemispherical probe, and local, where a nanometer-sized probe was used. For the sharp probe, a reduction in the elasticity modulus was observed in comparison to untreated control cells, that is related to the depolymerization of the cytoskeleton and the processes leading to cell apoptosis. In the case of the hemispherical probe, cell softening was also observed in comparison to control cells, but with increasing PAMAM concentrations, the modulus of elasticity increases. It is related to the sensing of numerous intracellular vesicles with the use of this probe, e.g. endosomal and empty plasmalemmal which can also alter cell elasticity. The presence of external and intracellular vesicles was confirmed by scanning and transmission electron microscopy. The relationship between the elasticity of HUVEC cells exposed to PAMAM dendrimers of selected generations and their toxic effects was presented herein for the first time. In the transmission electron microscopy images of the cells exposed to PAMAM dendrimers, we have also observed distinctive vesicles with regular multilayer arranged structure. [ABSTRACT FROM AUTHOR]

This publication describes analytical data for four psychoactive substances: 5F-PB-22, NM-2201, UR-144 and AB-CHMINACA. Compounds were synthesized in our laboratory and their presence was confirmed using electrospray ionisation mass spectrometry (ESI-MS), gas chromatography with electron ionization mass spectrometry detection (GC-EI-MS), gas chromatography with flame ionization detection (GC-FID), high-performance liquid chromatography (HPLC), Raman spectroscopy as well as proton nuclear magnetic resonance (1H NMR). Mass spectra show molecular ions and adducts peaks. Characteristic fragmentation patterns for cannabinoids can be seen by referring to GC-EI-MS mass spectra. Simple and sensitive HPLC methods were developed for the qualitative and quantitative determination of all synthesized compounds. RAMAN and GC-FID served as analytical tools for compound identification in the stability test. [ABSTRACT FROM AUTHOR]

The hybrid technology combines an efficient material‐removal process and implant surface treatment by the laser reducing time of manufacture process compared to currently used machining technologies. It also permits precise structuring of the implant material surface. Six structures of the Ti6Al4V ELI surface were designed and studied how the structure topography prepared with the hybrid technology affected the Escherichia coli adhesion to the surface and viability, as well as the growth, adhesion, and viability of human osteogenic Saos‐2 cells cultured on the investigated surfaces. Results have confirmed that the microtopography of medical titanium alloy plays a beneficial role in bacterial adhesion and viability (number of bacteria found on reference surface: [5.9 ± 0.44] × 106 CFU/ml, sample no. 3: [8.8 ± 0.93] × 104 CFU/ml, and sample no. 5: [1.2 ± 0.23] × 107 CFU/ml; CFU ‐ Colony Forming Unit). All tested structured surfaces enabled good cell attachment and proliferation of Saos‐2 cells (viability of Saos‐2 cells [% of control] for reference surface: 81.93%; sample no. 3: 75% and sample no. 5: 100%). Transcriptome analysis of genes commonly expressed in the process of osseointegration demonstrated that the use of hybrid technology allows designing structures that enhance osseointegration but it should be coupled with other methods of preventing bacterial growth, or with a different strategy to limit microbial colonization with the satisfactory osseointegration potential. [ABSTRACT FROM AUTHOR]