Ytterbium ion promotes apoptosis of primary mouse bone marrow stromal cells?

Cytotoxicity and Oxidative Stress Induced by Technology-Critical Elements versus Traditional Metal Contaminants: An In Vitro Bioassay Study

Technology-critical elements (TCEs), essential in emerging technologies, are increasingly finding their way into our environment, raising concerns about their sparsely studied behavior and toxicity. To contribute insights into the toxicological aspects, we employed in vitro bioassays to investigate the possible cytotoxic effects in four representative cell lines (AR-EcoScreen GR-KO-M1, DR-EcoScreen, MCF7AREc32, VM7Luc4E2) and the potential to induce oxidative stress via the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway for a number of these elements. Nine TCEs, three rare-earth elements (REEs: Gd, Nd, Yb) and six less-studied TCEs (LSTCEs: Ga, Ge, In, Ta, Te, Tl), were selected for this study, along with three well-studied traditional metal contaminants (TMCs: As, Cd, Pb) for comparison. Among the 12 studied elements, nine showed signs of inducing cytotoxicity: As, Cd, Ga, Nd, and Te in three out of the four studied cell lines and Gd, Ta, Tl, and Yb in one to two cell lines. Tellurium repeatedly exhibited the highest potency. The TCEs Ga and In, similar to As and Cd, also demonstrated the potential to induce oxidative stress. The results of this study suggest that some TCEs may potentially cause adverse health effects similar to As and Cd, thus prompting further investigations.

Rare Earth Complexes of Europium(II) and Substituted Bis(pyrazolyl)borates with High Photoluminescence Efficiency

Rare earth europium(II) complexes based on d-f transition luminescence have characteristics of broad emission spectra, tunable emission colors and short excited state lifetimes, showing great potential in display, lighting and other fields. In this work, four complexes of Eu(II) and bis(pyrazolyl)borate ligands, where pyrazolyl stands for pyrazolyl, 3-methylpyrazolyl, 3,5-dimethylpyrazolyl or 3-trifluoromethylpyrazole, were designed and synthesized. Due to the varied steric hindrance of the ligands, different numbers of solvent molecules (tetrahydrofuran) are participated to saturate the coordination structure. These complexes showed blue-green to yellow emissions with maximum wavelength in the range of 490-560 nm, and short excited state lifetimes of 30-540 ns. Among them, the highest photoluminescence quantum yield can reach 100%. In addition, when the complexes were heated under vacuum or nitrogen atmosphere, they finally transformed into the complexes of Eu(II) and corresponding tri(pyrazolyl)borate ligands and sublimated away.

Complexes of Ce(III) and Bis(pyrazolyl)borate Ligands: Synthesis, Structures, and Luminescence Properties

Luminescent cerium(III) complexes based on the d-f transition have characteristics of broad emission spectra, tunable emission colors, and short excited state lifetimes, showing potential applications in display, lighting, and other fields. Thus it is important to construct luminescent Ce(III) complexes with high photoluminescence efficiency and good stability. In this work, five Ce(III) complexes with dihydrobis(pyrazolyl)borate or diphenylbis(pyrazolyl)borate ligands, where pyrazolyl stands for pyrazolyl, 3-methylpyrazolyl, or 3,5-dimethylpyrazolyl, were designed and synthesized, showing emission colors from deep blue to yellow with a maximum wavelength in the range of 390-560 nm, short excited state lifetimes of 30-80 ns, and photoluminescence quantum yields exceeding 75% in solid powder. By comparing these complexes, it is found that higher photoluminescence efficiency and better thermal/air stability could be achieved in the complexes with dihydrobis(pyrazolyl)borate ligands.

Deep-blue emitting cerium(III) complexes with tris(pyrazolyl)borate and triflate ligand

Red, green and blue emitting materials, the three-primary colors, are very important in lighting and display. Red-emitting Eu(III) complexes and green-emitting Tb(III) complexes exhibit high color purity and photoluminescence (PL)...

Enhanced mesenchymal stem cell proliferation through complexation of selenium/titanium nanocomposites

The main target of this work was to explore the proliferative impact of selenium dioxide nanoparticles (SeO₂) and selenium dioxide/titanium dioxide nanocomposites (Se/Ti (I), (II) and (III)) on mesenchymal stem cells (MSCs). For this purpose, SeO₂ and Se/Ti (I), (II) and (III) were prepared by facile one step method and characterized by transmission electron microscopy (TEM), Zetasizer, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) along with energy-dispersive X-ray spectrometry (EDX) with reference to SeO₂ nanoparticles. Also, MSCs were isolated from rat bone marrow (BM-MSCs) and adipose tissue (ADSCs), propagated and characterized by flow cytometry. Thereafter, the proliferative effect of the fabricated nanomaterials was investigated by MTT assay. The TEM and DLS results, revealed that the average particle size of the suggested nanomaterials was in nanoscale. XRD pattern showed well crystalline structure for SeO₂ nanoparticles and Se/Ti (I), (II) and (III) nanocomposites; the decreasing of the crystalline phase was observed by increasing the wt% of TiO₂. The designed nanomaterials showed proliferative effects on MSCs with the most prominent effect exerted by 2 µg/ml of Se/Ti (III) and 5 µg/ml of Se/Ti (II) for ADSCs and 20 µg/ml of Se/Ti (II) and 10 µg/ml of Se/Ti (III) for BM-MSCs. Therefore, these newly designed nanomaterials have a promising influence on MSCs proliferation and they are recommended to be utilized in the filed of tissue engineering.