Low-Dose Exposure of WS₂ Nanosheets Induces Differential Apoptosis in Lung Epithelial Cells

Escalating the production and application of tungsten disulfide (WS2) nanosheets inevitably increases environmental human exposure and warrants the necessity of studies to elucidate their biological impacts. Herein, we assessed the toxicity of WS2 nanosheets and focused on the impacts of low doses (≤10 μg/mL) on normal (BEAS-2B) and tumorigenic (A549) lung epithelial cells. The low doses, which approximate real-world exposures, were found to induce cell apoptosis, while doses ≥ 50 μg/mL cause necrosis. Focused studies on low-dose exposure to WS2 nanosheets revealed more details of the impacts on both cell lines, including reduction of cell metabolic activity, induction of lipid peroxidation in cell membranes, and uncoupling of mitochondrial oxidative phosphorylation that led to the loss of ATP production. These phenomena, along with the expression situations of a few key proteins involved in apoptosis, point toward the occurrence of mitochondria-dependent apoptotic signaling in exposed cells. Substantial differences in responses to WS2 exposure between normal and tumorigenic lung epithelial cells were noticed as well. Specifically, BEAS-2B cells experienced more adverse effects and took up more nanosheets than A549 cells. Our results highlight the importance of dose and cell model selection in the assessment of nanotoxicity. By using doses consistent with real-world exposures and comparing normal and diseased cells, we can gain knowledge to guide the development of safety precautions for mitigating the adverse impacts of nanomaterial exposure on human health

Enhancing Extracellular Vesicle Analysis by Integration of Large-Volume Sample Stacking in Capillary Electrophoresis with Asymmetrical Flow Field-Flow Fractionation

Extracellular vesicles (EVs) play important roles in cell–cell communication and pathological development. Cargo profiling for the EVs present in clinical specimens can provide valuable insights into their functions and help discover effective EV-based markers for diagnostic and therapeutic purposes. However, the highly abundant and complex matrix components pose significant challenges for specific identification of low-abundance EV cargos. Herein, we combine asymmetrical flow field-flow fractionation (AF4) with large-volume sample stacking and capillary electrophoresis (LVSS/CE), to attain EVs with high purity for downstream protein profiling. This hyphenated system first separates the EVs from the contamination of smaller serum proteins by AF4, and second resolves the EVs from the coeluted, nonvesicular matrix components by CE following LVSS. The optimal LVSS condition permits the injection of 10-fold more EVs into CE compared to the nonstacking condition without compromising separation resolution. Collection and downstream analysis of the highly pure EVs after CE separation were demonstrated in the present work. The high EV purity yields a much-improved labeling efficiency when detected by fluorescent antibodies compared to those collected from the one-dimension separation of AF4, and permits the identification of more EV-specific cargos by LC–MS/MS compared to those isolated by ultracentrifugation (UC), the exoEasy Maxi Kit, and AF4. Our results strongly support that AF4-LVSS/CE can improve EV isolation and cargo analysis, opening up new opportunities for understanding EV functions and their applications in the biomedical fields

sj-pdf-1-mpp-10.1177_23814683231202716 – Supplemental material for Adaptive COVID-19 Mitigation Strategies

Supplemental material, sj-pdf-1-mpp-10.1177_23814683231202716 for Adaptive COVID-19 Mitigation Strategies by Erinn C. Sanstead, Zongbo Li, Shannon B. McKearnan, Szu-Yu Zoe Kao, Pamela J. Mink, Alisha Baines Simon, Karen M. Kuntz, Stefan Gildemeister and Eva A. Enns in MDM Policy & Practice</p

Additional file 1: Table S1. of Serotype distribution and antibiotic resistance of Streptococcus pneumoniae isolates from 17 Chinese cities from 2011 to 2016

Number of Streptococcus pneumoniae strains in different cities and years. This table describes the numbers of strains in different cities and years. The cities in this table were divided into 3 group based on the annual per capita GDP. (DOCX 16 kb