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Pharmacology Research & Perspectives Aug 2021This study explored the binding of 28 drugs, which were selected based on frequency of concomitant use and chemical properties, to sevelamer and polystyrene sulfonate in...
This study explored the binding of 28 drugs, which were selected based on frequency of concomitant use and chemical properties, to sevelamer and polystyrene sulfonate in vitro. The relative binding was determined by dissolving the investigated drugs alone (=control), together with 800 mg of sevelamer and 15 g of polystyrene sulfonate at different pH levels (1.5, 5.5, and 7.4), respectively. After incubation at 37℃ and shaking for 60 min, the solutions were diluted and centrifuged, and the drug concentrations were quantified with validated analytical assays. The binding assays were performed in threefold. The mean relative binding (MRB) at each pH level was calculated, with a MRB >20% for at least one pH level to be considered as relevant binding. Fourteen and 23 potentially new binding interactions were identified with sevelamer and polystyrene sulfonate, respectively. These potentially new binding interactions have to be studied in vivo to assess their clinical relevance.
Topics: Hydrogen-Ion Concentration; Pharmaceutical Preparations; Polystyrenes; Sevelamer
PubMed: 34302439
DOI: 10.1002/prp2.834 -
Ecotoxicology and Environmental Safety Mar 2022Vast amounts of plastic materials are produced in the modern world and despite recycling efforts, large amounts are disposed in water systems and landfills. Under these...
Vast amounts of plastic materials are produced in the modern world and despite recycling efforts, large amounts are disposed in water systems and landfills. Under these storage conditions, physical weathering and photochemical processes break down these materials into smaller particles of the micro- and nano-scale. In addition, ecosystems can be contaminated with plastic particles which are manufactured in these size ranges for commercial purposes. Independent of source, microplastics are abundant in the environment and have found their way into water supplies and the food cycle where human exposure is inevitable. Nevertheless, the health consequences of microplastic ingestion, inhalation, or absorption are largely unknown. In this study we sought to determine if ingestion of microplastics promoted pre-clinical cardiovascular disease (CVD). To do this, we supplied mice with normal drinking water or that supplemented with polystyrene beads of two different sizes (0.5 µm and 5 µm) and two different doses (0.1 μg/ml and 1 μg/ml) each for 12 weeks and measured several indices of metabolism and glucose homeostasis. As early as 3 weeks of consumption, we observed an accelerated weight gain with a corresponding increase in body fat for some exposure groups versus the control mice. Some exposure groups demonstrated increased levels of fasting plasma glucose. Those mice consuming the smaller sized beads (0.5 µm) at the higher dose (1 μg/ml), had increased levels of fasting plasma insulin and higher homeostatic model assessment of insulin resistance (HOMA-IR) scores as well. This was accompanied by changes in the gut microbiome consistent with an obese phenotype. Using samples of perivascular adipose tissue collected from the same group, we observed changes in gene expression consistent with increased adipogenesis. These results suggest that ingestion of polystyrene beads promotes a cardiometabolic disease phenotype and thus may be an unrecognized risk factor for CVD.
Topics: Adiposity; Animals; Cardiovascular Diseases; Eating; Ecosystem; Mice; Obesity; Plastics; Polystyrenes
PubMed: 35093814
DOI: 10.1016/j.ecoenv.2022.113239 -
Analytical Chemistry Aug 2022The development of new technologies for the separation, selection, and isolation of microparticles such as rare target cells, circulating tumor cells, cancer stem cells,...
The development of new technologies for the separation, selection, and isolation of microparticles such as rare target cells, circulating tumor cells, cancer stem cells, and immune cells has become increasingly important in the last few years. Microparticle separation technologies are usually applied to the analysis of disease-associated cells, but these procedures often face a cell separation problem that is often insufficient for single specific cell analyses. To overcome these limitations, a highly accurate size-based microparticle separation technique, herein called "rotating magnetic chromatography", is proposed in this work. Magnetic nanoparticles, placed in a microfluidic separation channel, are forced to move in well-defined trajectories by an external magnetic field, colliding with microparticles that are in this way separated on the basis of their dimensions with high accuracy and reproducibility. The method was optimized by using fluorescein isothiocyanate-modified polystyrene particles (chosen as a reference standard) and then applied to the analysis of cancer cells like Hep-3B and SK-Hep-1, allowing their fast and high-resolution chromatographic separation as a function of their dimensions. Due to its unmatched sub-micrometer cell separation capabilities, RMC can be considered a break-through technique that can unlock new perspectives in different scientific fields, that is, in medical oncology.
Topics: Cell Separation; Chromatography; Magnetic Phenomena; Magnetics; Polystyrenes; Reproducibility of Results
PubMed: 35943850
DOI: 10.1021/acs.analchem.2c01385 -
Chemosphere Nov 2022Microorganisms play an important role in biogeochemical cycles, and are inevitably found associated with plastic debris. The interplay between microbes and plastics may...
Microorganisms play an important role in biogeochemical cycles, and are inevitably found associated with plastic debris. The interplay between microbes and plastics may change the characteristics of certain plastics over time and drive the environmental fate of plastics. In this study, we evaluated interactions of bacteria with nano- and microplastics. Here, polystyrene (PS) polymer particles of various diameters, specifically 60, 220, 430, 700, 1040, 1700, and 2260 nm, were used as the plastics. Escherichia coli (E. coli, gram-negative) and Bacillus sp. (gram-positive) were chosen as model bacteria. The effects of nano- and microPS particles on E. coli and Bacillus sp. cells were investigated by measuring the growth and viability of the cells in laboratory-scale flasks and their generation of reactive oxygen species (ROS) upon their exposure to these particles of 100 mg/L. The particles inhibited the growth and viability of both types of bacterial cells, but their inhibitory effects varied depending on the diameter of PS particle. The 60-nm-diameter PS particles were visually observed to enter the cells as well as accumulate on their surfaces and enhanced ROS generation of the cells. Unexpectedly, the 1040-nm-diameter PS particles, similar in size to the bacterial cells, inhibited the growth of both E. coli and Bacillus sp. cells the most. The E. coli and Bacillus sp. cells formed microPS-biofilm complex by secreting an extracellular polymeric substance (EPS) in response to their exposure to the ∼ 1-μm-diameter PS particles. A positive correlation between relative ROS levels and specific growth rates of the E. coli cells were observed with a Pearson correlation coefficient r value of 0.676 (p < 0.05).
Topics: Bacteria; Escherichia coli; Extracellular Polymeric Substance Matrix; Microscopy; Plastics; Polystyrenes; Reactive Oxygen Species; Water Pollutants, Chemical
PubMed: 35798153
DOI: 10.1016/j.chemosphere.2022.135584 -
International Journal of Biological... May 2023Nanoplastics are an emerging environmental contaminant that can penetrate biological barriers to enter the bloodstream and risk human health. In this context,...
Nanoplastics are an emerging environmental contaminant that can penetrate biological barriers to enter the bloodstream and risk human health. In this context, nanoplastics are likely to interact with proteins in the blood to possibly affect protein structure and function and consequently induce biological effects. Here we report that polystyrene (PS), PS-NH, and PS-COOH nanoplastics disrupt the structure of human fibrinogen (HF) in a dose-dependent manner, as revealed by UV-vis and fluorescence spectroscopy. All three nanoplastics interacted with HF in a similar way, with PS-NH having the greatest effect on HF structure. Furthermore, fibrinogen polymerization experiments demonstrated that nanoplastics have the potential to promote blood coagulation, with PS-NH again having a stronger effect. Collectively, these results provide insights into the interactions occurring between nanoplastics and HF, the likely transport and fate of nanoplastics in organisms, and their potential pathophysiological consequences.
Topics: Humans; Polystyrenes; Microplastics; Fibrinogen; Nanoparticles; Water Pollutants, Chemical
PubMed: 36931485
DOI: 10.1016/j.ijbiomac.2023.124049 -
Nanomedicine : Nanotechnology, Biology,... Jun 2023Micro- and nano-plastics (MPs and NPs) released from plastics in the environment can enter the food chain and target the human intestine. However, knowledge about the...
Micro- and nano-plastics (MPs and NPs) released from plastics in the environment can enter the food chain and target the human intestine. However, knowledge about the effects of these particles on the human intestine is still limited due to the lack of relevant human intestinal models to validate data obtained from animal studies or tissue models employing cancer cells. In this study, human intestinal organoids were used to develop epithelia to mimic the cell complexity and functions of native tissue. Microfold cells (M cells) were induced to distinguish their role when exposure to MPs and NPs. During the exposure, the M cells acted as sensors, capturers and transporters of larger sized particles. The epithelial cells internalized the particles in a size-, concentration-, and time-dependent manner. Importantly, high concentrations of particles significantly triggered the secretion of a panel of inflammatory cytokines linked to human inflammatory bowel disease (IBD).
Topics: Animals; Humans; Microplastics; Polystyrenes; M Cells; Organoids; Epithelium
PubMed: 37105344
DOI: 10.1016/j.nano.2023.102680 -
International Journal of... 2024Ethylenediamine-N,N'-disuccinic acid (EDDS) has been studied extensively for its potential use as an amendment in agriculture due to its numerous beneficial properties....
Ethylenediamine-N,N'-disuccinic acid (EDDS) has been studied extensively for its potential use as an amendment in agriculture due to its numerous beneficial properties. The widespread usage of microplastics (MPs) poses a growing threat to plant growth. This study investigated the effects of Polystyrene MPs (PSMPs) and EDDS on soil pH, EC, organic matter (OM), available nutrients, and maize ( L.) growth in a calcareous soil. Results showed that both PS and EDDS had significant effects on soil pH, with higher concentrations leading to a decrease in pH. PSMPs negatively impacted soil health by increasing EC and decreasing OM, nitrogen (N), phosphorus (P), and potassium (K). EDDS had potential applications in soil remediation and phytoremediation by decreasing EC and increasing N, P, and K. The interaction between EDDS and PSMPs suggests that their effects on soil pH may be modulated by each other. The study highlights the potential negative impacts of high concentrations of PS on soil health and the potential benefits of using EDDS at lower concentrations in soil remediation and phytoremediation. However, further research is needed to understand the mechanisms and environmental impacts of EDDS and the combined effects of EDDS and PSMPs on soil properties and plant growth.
Topics: Soil; Polystyrenes; Biodegradation, Environmental; Plastics; Agriculture; Zea mays; Soil Pollutants
PubMed: 37667464
DOI: 10.1080/15226514.2023.2250464 -
International Journal of Molecular... Nov 2023Polymers' controlled pyrolysis is an economical and environmentally friendly solution to prepare activated carbon. However, due to the experimental difficulty in...
Polymers' controlled pyrolysis is an economical and environmentally friendly solution to prepare activated carbon. However, due to the experimental difficulty in measuring the dependence between microstructure and pyrolysis parameters at high temperatures, the unknown pyrolysis mechanism hinders access to the target products with desirable morphologies and performances. In this study, we investigate the pyrolysis process of polystyrene (PS) under different heating rates and temperatures employing reactive molecular dynamics (ReaxFF-MD) simulations. A clear profile of the generation of pyrolysis products determined by the temperature and heating rate is constructed. It is found that the heating rate affects the type and amount of pyrolysis intermediates and their timing, and that low-rate heating helps yield more diverse pyrolysis intermediates. While the temperature affects the pyrolytic structure of the final equilibrium products, either too low or too high a target temperature is detrimental to generating large areas of the graphitized structure. The reduced time plots (RTPs) with simulation results predict a PS pyrolytic activation energy of 159.74 kJ/mol. The established theoretical evolution process matches experiments well, thus, contributing to preparing target activated carbons by referring to the regulatory mechanism of pyrolytic microstructure.
Topics: Polystyrenes; Molecular Dynamics Simulation; Pyrolysis; Temperature; Heating
PubMed: 38003591
DOI: 10.3390/ijms242216403 -
Drug Delivery and Translational Research Aug 2021We report the first demonstration of the efficient bacteria targeting properties of DNA-based polymeric micelles with high-density DNA corona. Nanoscale polymer micelles...
We report the first demonstration of the efficient bacteria targeting properties of DNA-based polymeric micelles with high-density DNA corona. Nanoscale polymer micelles derived from DNA-b-polystyrene (DNA-b-PS) efficiently selected most tested Gram-positive strains over Gram-negative strains; single-strand DNAs were 20-fold less selective. We demonstrate that these targeting properties were derived from the interaction between densely packed DNA strands of the micelle corona and the peptidoglycan layers of Gram-positive bacteria. DNA-b-PS micelles incorporating magnetic nanoparticles (MNPs) can efficiently capture and concentrate Gram-positive bacteria suggesting the simple applications of these DNA block copolymer micelles for concentrating bacteria. Adenine (A), thymine (T), cytosine (C), and guanine (G)-rich nanostructures were fabricated, respectively, for investigating the effect of sequence on Gram-selective bacteria targeting. T-rich micelles showed the most efficient targeting properties. The targeting properties of these DNA nanostructures toward Gram-positive bacteria may have applications as a targeted therapeutic delivery system.
Topics: DNA; Gram-Positive Bacteria; Micelles; Nanostructures; Polystyrenes
PubMed: 33880733
DOI: 10.1007/s13346-021-00975-w -
Environmental Pollution (Barking, Essex... May 2023Microplastics (MPs) are a type of emerging pollutant, posing a great threat to human and animal health. While recent studies have revealed the link between MPs exposure...
Microplastics (MPs) are a type of emerging pollutant, posing a great threat to human and animal health. While recent studies have revealed the link between MPs exposure and liver injury of organisms, the effect of particle size on the level of MPs-induced hepatotoxicity and the intrinsic mechanism remain to be explored. Here, we established a mouse model exposed to two-diameter polystyrene MPs (PS-MPs, 1-10 μm or 50-100 μm) for 30 days. The in vivo results revealed that PS-MPs caused liver fibrotic injury in mice, accompanied with macrophages recruitment and macrophage extracellular traps (METs) formation, which were negatively correlated with particle size. The data in vitro showed that PS-MPs treatment could induce macrophages to release METs in a reactive oxygen species (ROS)-independent manner, and the METs formation level caused by large-size particles was higher than small-size particles. Further mechanistic analysis of a cell co-culture system revealed that PS-MPs-induced METs release led to a hepatocellular inflammatory response and epithelial-mesenchymal transition (EMT) via activating the ROS/TGF-β/Smad2/3 signaling axis, and this biological crosstalk could be relieved by DNase I. Overall, this findings demonstrates the key role of the action mechanism of METs in aggravating MPs-caused liver injury.
Topics: Mice; Humans; Animals; Polystyrenes; Microplastics; Plastics; Reactive Oxygen Species; Extracellular Traps; Liver; Smad2 Protein
PubMed: 36871749
DOI: 10.1016/j.envpol.2023.121388