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Povzetek: Glioblastoma (GB) is an aggressive primary brain cancer with poor patient prognosis. Natural killer (NK) cells can recognise and eliminate a range of malignant cells, including GB stem cells, which drive GB recurrence. NK cell-based immunotherapy has emerged as a promising approach for GB treatment, but a better understanding of the complex crosstalk between GB and NK cells is needed, particularly within the immunosuppressive GB tumour microenvironment. In this study, we established a reproducible protocol for the production and dynamic culture of uniformly sized GB spheroids using the Celvivo Clinostar system. Our spheroids recapitulated the heterogeneous structure of GB and expressed ligands for NK cell receptors at levels distinct from those observed in corresponding GB cell lines in standard culture, implicating altered sensitivity of GB cells to NK cells in dynamic 3D cultures. GB-NK cell crosstalk was GB cell type dependent and the ability of NK cells to infiltrate GB did not necessarily correlate with their cytotoxicity against GB cells. Spheroids derived from differentiated GB cells secreted higher levels of immunomodulatory cytokines compared to spheroids from GB stem-like cells, and a prominent increase in the secretion of immune-attracting factors was observed in their co-cultures with NK cells. Finally, the CD155-DNAM1/TIGIT axis was indicated as an important regulator of NK cell cytotoxicity against GB stem-like cells. Collectively, our results highlight important factors in GB-NK cell communication and provide a groundwork for further targeted research as well as therapeutic evaluation of NK cell-based approaches in the established dynamic 3D cultures.
Ključne besede: glioblastoma, immunotherapy, dynamic in vitro models, natural killer cells, cytotoxicity, 21 infiltration, cytokines, CD155
Objavljeno v DiRROS: 11.06.2026; Ogledov: 86; Prenosov: 55
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Povzetek: Background: Clear aligners have become a common alternative to fixed appliances for tooth movement, and thermoplastic retainers hold the outcome. The prolonged intraoral contact of these devices has made the materials a focus of biocompatibility research. Objectives: This paper aims to summarize laboratory evidence on the biocompatibility of clear aligners and thermoplastic retainers. Materials included thermoformed polyethylene terephthalate glycol-modified (PETG), multilayer polyurethane, and directly printed resins. Primary outcomes were cytotoxicity, endocrine activity, and chemical or particle release. Methods: We systematically searched PubMed, the Cochrane Library, and Google Scholar through 31 May 2025, and we followed the PRISMA 2020 statement (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). We applied predefined eligibility criteria. Two reviewers screened records and extracted data in duplicate, including study design, extraction conditions, surface-area-to-volume ratio (SA/V), cell models, endpoints, and analytical sensitivity as the limit of detection (LOD) and limit of quantification (LOQ). We assessed the risk of bias across seven domains and graded certainty by outcome. We did not register a protocol prospectively. Results: Seventeen studies met the inclusion criteria. Materials spanned multilayer polyurethanes (SmartTrack, Clarity), PETG sheets (Essix ACE, Duran), and directly printed resins (Graphy TC-85DAC); a subset tested zinc-oxide (ZnO) nanoparticle coatings. Typical extractions immersed 0.1–1 g of material in cell-culture medium or artificial saliva at 37 °C for 24 h to 30 days. Cell viability usually remained ≥80%. Mild cytotoxicity (about 60–70% viability) appeared with harsher extractions, extended soaks, or an inadequate post-curing of printed parts. The estrogen-sensitive proliferation assay (E-Screen) returned negative results. In saliva-like media, bisphenol A (BPA) and related leachables were undetectable or in the low ng/mL range. In printed resins, urethane dimethacrylate (UDMA) sometimes appeared in water extracts, and amounts varied with curing quality. Evidence for chemical leaching and endocrine outcomes is sparse. We found no eligible in vitro study that quantified particle or microplastic release while also measuring a biological endpoint; we discuss particle findings from mechanical wear simulations only as the external context. Limitations: The evidence base is limited to in vitro studies. Many reports incompletely described extraction ratios and processing parameters. Risk of bias and certainty: Most studies used appropriate cell models and controls, but the reporting of surface-area-to-volume ratios, LOD/LOQ, and detailed post-processing parameters was often incomplete. Sample sizes were small, and dynamic wear or enzymatic conditions were uncommon. The overall risk of bias was moderate, and the certainty of evidence was low to moderate due to heterogeneity and in vitro indirectness. Conclusions: Under standard laboratory conditions, clear aligners and thermoplastic retainers show a favorable biocompatibility profile. For printed resins, outcomes depend mainly on processing quality, especially thorough washing and appropriate light-curing parameters. To improve comparability and support clinical translation, we recommend harmonized test protocols, transparent reporting, interlaboratory ring trials, and targeted clinical biomonitoring.
Ključne besede: biocompatibility, clear aligner, thermoplastic retainer, cytotoxicity
Objavljeno v DiRROS: 01.06.2026; Ogledov: 113; Prenosov: 84
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Ključne besede: cytotoxicity, genomic instability, in silico, indoor air pollution, public health, environmental toxicology
Objavljeno v DiRROS: 20.03.2026; Ogledov: 301; Prenosov: 220
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Povzetek: The increasing complexity of aquatic pollution, dominated by diverse and often uncharacterized chemical mixtures, challenges traditional monitoring approaches. In this study, we assessed the genotoxic potential of surface water samples collected during the Joint Danube Survey 4 (JDS4) using large-volume solid-phase extraction (LVSPE) combined with a comprehensive battery of bioassays. Twenty-three enriched water samples from the Danube River and its major tributaries were evaluated for genotoxicity using a tiered testing strategy comprising the SOS/umuC assay, zebrafish liver (ZFL) cell-based assays (cytotoxicity, comet assay, cell cycle), and zebrafish embryo assays. While no genotoxicity was detected in the prokaryotic SOS/umuC assay, ZFL assays revealed significant DNA damage in 16 out of 23 samples, with notable genotoxicity observed in samples from the middle Danube section. In contrast, no teratogenic effects were observed in zebrafish embryo assays at concentrations up to REF100. These findings demonstrate the superior sensitivity of ZFL cells compared to both prokaryotic and in vivo embryo models. The study also highlights a critical gap in available genotoxicity data for detected substances, emphasizing the need for standardized databases and testing frameworks. Overall, our results support zebrafish-based in vitro assays as effective tools for effect-based monitoring, providing early warnings of genotoxic pollution in complex aquatic environments.
Ključne besede: ZFL cell line, zebrafish embryos, cytotoxicity, genotoxicity, Danube River
Objavljeno v DiRROS: 28.01.2026; Ogledov: 409; Prenosov: 478
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Povzetek: Chitosan is a water-soluble polysaccharide with good adherence to negatively charged surfaces and reported antimicrobial and anti-inflammatory properties. Coating the surfaces of medical devices with chitosan is a promising strategy for harnessing these benefits. However, the surface properties of commercial polymers need to be altered to enable the bonding of thin chitosan films. In this study, the adhesion of chitosan onto plasma-treated polyvinyl chloride (PVC) and the metabolic activity of urothelial cells on chitosan-coated medical-grade PVC used for the synthesis of urinary catheters were evaluated. To improve the adhesion of chitosan onto the PVC catheters, PVC samples were made “super-hydrophilic”. PVC substrates were briefly treated with a powerful hydrogen plasma and weakly ionised oxygen plasma afterglow to obtain a chlorine-free surface film, which was rich in oxygen functional groups, followed by incubation of the plasma-treated substrates in an aqueous solution of chitosan. Then, urothelial RT4 cells were seeded on the treated and untreated PVC substrates, and their metabolic activity, confluency, and cell morphology were examined. X-ray photoelectron spectroscopy was used to measure the nitrogen concentration, which corresponded to the chitosan concentration on the substrate. The results showed that the substrates were uniformly covered by a thin layer of chitosan only on plasma-treated surfaces and not on untreated surfaces. Moreover, the chitosan coating provided a stimulated environment for cell adhesion and growth. In conclusion, the chitosan-coated super-hydrophilic PVC substrate shows potential to improve the overall performance and safety of medical devices such as urinary catheters.
Ključne besede: medical-grade PVC, chitosan coating, urinary catheter, urothelial cells, cytotoxicity, adhesion, biocompatibility
Objavljeno v DiRROS: 28.02.2025; Ogledov: 1017; Prenosov: 653
Celotno besedilo (14,65 MB)
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