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PloS One 2022Hydrophilic materials immersed in aqueous solutions show near-surface zones that exclude suspended colloids and dissolved molecules. These exclusion zones (EZs) can...
Hydrophilic materials immersed in aqueous solutions show near-surface zones that exclude suspended colloids and dissolved molecules. These exclusion zones (EZs) can extend for tens to hundreds of micrometers from hydrophilic surfaces and show physicochemical properties that differ from bulk water. Here we report that exposure of standard aqueous microsphere suspensions to static magnetic fields creates similar microsphere-free zones adjacent to magnetic poles. The EZs build next to both north and south poles; and they build whether the microspheres are of polystyrene or carboxylate composition. EZ formation is accompanied by ordered motions of microspheres, creating dense zones some distance from the magnetic poles and leaving microsphere-free zones adjacent to the magnet. EZ size was larger next to the north pole than the south pole. The difference was statistically significant when polystyrene microspheres were used, although not when carboxylate microspheres were used. In many ways, including both size and dynamics, these exclusion zones resemble those found earlier next to various hydrophilic surfaces. The ability to create EZs represents a feature of magnets not previously revealed.
Topics: Hydrophobic and Hydrophilic Interactions; Magnetic Fields; Microspheres; Polystyrenes; Water
PubMed: 35622780
DOI: 10.1371/journal.pone.0268747 -
La Revue de Medecine Interne Jun 2024Hyperkalemia is common in everyday clinical practice, and is a major risk factor for mortality. It mainly affects patients with chronic renal failure (CKD), diabetes or... (Review)
Review
Hyperkalemia is common in everyday clinical practice, and is a major risk factor for mortality. It mainly affects patients with chronic renal failure (CKD), diabetes or receiving treatment with inhibitors of the renin-angiotensin-aldosterone system (iRAAS). Therapeutic management aims not only to avoid the complications of hyperkalemia, but also to avoid discontinuation of cardio- and nephroprotective treatments such as iRAAS. The use of polystyrene sulfonate, widely prescribed, is often limited by patient acceptability. Recent data have cast doubt on its safety, particularly in terms of digestive tolerance. Two new potassium exchange molecules have appeared on the market: patiromer and zirconium sulfonate. Their value in clinical practice, and their acceptability in the event of prolonged prescription, remain to be demonstrated. The combination of a thiazide diuretic or an inhibitor of the sodium-glucose cotransporter type 2 (iSGLT2) with iRAAS therapy in CKD, may also improve control of kalemia. At present, there are no recommendations for the positioning of the various hypokalemic treatments. The choice of these treatments must be adapted to the patient's pathologies and consider the other expected effects of these molecules.
Topics: Hyperkalemia; Humans; Polystyrenes; Renin-Angiotensin System; Potassium; Renal Insufficiency, Chronic; Polymers
PubMed: 38220492
DOI: 10.1016/j.revmed.2024.01.004 -
International Journal of Nanomedicine 2022Micro- and nano-sized plastics (MPs and NPs) have become an environmental issue of global concern due to their small size, strong bio-permeability and high specific...
BACKGROUND
Micro- and nano-sized plastics (MPs and NPs) have become an environmental issue of global concern due to their small size, strong bio-permeability and high specific surface area. However, few studies have assessed the effect of polystyrene MPs and NPs on human lung cells. In this research, we evaluated the cytotoxicity and genotoxicity of polystyrene (PS) MPs and NPs with different sizes (2 μm and 80 nm) and surface modification (carboxy and amino functionalized polystyrene, pristine polystyrene) in A549 cells.
METHODS
The zeta potential and hydrodynamic particle size of five types of PS plastic solutions were measured by dynamic light scattering, and their morphology and degree of aggregation were observed by scanning electron microscopy. After incubation of the PS plastics with A549 cells, the uptake and toxicity of the cells were assessed by fluorescence microscopy, laser scanning confocal microscopy, flow cytometry, MTT, micronucleus formation assay, and reactive oxygen species.
RESULTS
The cytotoxicity and genotoxicity of A549 cells caused by nano-level PS is more serious than that of micro-level. Compared with unmodified PS-NPs, more surface-functionalized PS-NPs were found inside the cells, especially the accumulation of PS-NH. Cell viability and the induction of micronuclei (MN) are appreciably impacted in a dose-dependent way. Compared with pristine PS-NPs, functionalized PS-NPs showed stronger cell viability inhibitory ability, and induced more MN scores.
CONCLUSION
This study shows that the intrinsic size properties and surface modification of PS plastics, the interaction between PS plastics and the receiving medium, intracellular accumulation are critical factors for evaluating the toxicological influences of PS plastics on humans.
Topics: A549 Cells; Humans; Microplastics; Nanoparticles; Plastics; Polystyrenes; Reactive Oxygen Species; Water Pollutants, Chemical
PubMed: 36186531
DOI: 10.2147/IJN.S381776 -
Environment International Mar 2023Nanomaterials are widespread in the human environment as pollutants, and are being actively developed for use in human medicine. We have investigated how the size and...
Nanomaterials are widespread in the human environment as pollutants, and are being actively developed for use in human medicine. We have investigated how the size and dose of polystyrene nanoparticles affects malformations in chicken embryos, and have characterized the mechanisms by which they interfere with normal development. We find that nanoplastics can cross the embryonic gut wall. When injected into the vitelline vein, nanoplastics become distributed in the circulation to multiple organs. We find that the exposure of embryos to polystyrene nanoparticles produces malformations that are far more serious and extensive than has been previously reported. These malformations include major congenital heart defects that impair cardiac function. We show that the mechanism of toxicity is the selective binding of polystyrene nanoplastics nanoparticles to neural crest cells, leading to the death and impaired migration of those cells. Consistent with our new model, most of the malformations seen in this study are in organs that depend for their normal development on neural crest cells. These results are a matter of concern given the large and growing burden of nanoplastics in the environment. Our findings suggest that nanoplastics may pose a health risk to the developing embryo.
Topics: Animals; Pregnancy; Female; Chick Embryo; Humans; Neural Crest; Microplastics; Polystyrenes; Heart Defects, Congenital; Embryonic Development
PubMed: 36907039
DOI: 10.1016/j.envint.2023.107865 -
Particle and Fibre Toxicology Nov 2023Nanoplastics (NPs) could be released into environment through the degradation of plastic products, and their content in the air cannot be ignored. To date, no studies...
BACKGROUND
Nanoplastics (NPs) could be released into environment through the degradation of plastic products, and their content in the air cannot be ignored. To date, no studies have focused on the cardiac injury effects and underlying mechanisms induced by respiratory exposure to NPs.
RESULTS
Here, we systematically investigated the cardiotoxicity of 40 nm polystyrene nanoplastics (PS-NPs) in mice exposed via inhalation. Four exposure concentrations (0 µg/day, 16 µg/day, 40 µg/day and 100 µg/day) and three exposure durations (1 week, 4 weeks, 12 weeks) were set for more comprehensive information and RNA-seq was performed to reveal the potential mechanisms of cardiotoxicity after acute, subacute and subchronic exposure. PS-NPs induced cardiac injury in a dose-dependent and time-dependent manner. Acute, subacute and subchronic exposure increased the levels of injury biomarkers and inflammation and disturbed the equilibrium between oxidase and antioxidase activity. Subacute and subchronic exposure dampened the cardiac systolic function and contributed to structural and ultrastructural damage in heart. Mechanistically, violent inflammatory and immune responses were evoked after acute exposure. Moreover, disturbed energy metabolism, especially the TCA cycle, in the myocardium caused by mitochondria damage may be the latent mechanism of PS-NPs-induced cardiac injury after subacute and subchronic exposure.
CONCLUSION
The present study evaluated the cardiotoxicity induced by respiratory exposure to PS-NPs from multiple dimensions, including the accumulation of PS-NPs, cardiac functional assessment, histology observation, biomarkers detection and transcriptomic study. PS-NPs resulted in cardiac injury structurally and functionally in a dose-dependent and time-dependent manner, and mitochondria damage of myocardium induced by PS-NPs may be the potential mechanism for its cardiotoxicity.
Topics: Animals; Mice; Cardiotoxicity; Polystyrenes; Microplastics; Myocardium; Biomarkers; Nanoparticles
PubMed: 38031128
DOI: 10.1186/s12989-023-00557-3 -
Ecotoxicology and Environmental Safety Jun 2022The use of polystyrene micro and nanoplastics in cosmetics and personal care products continues to grow every day. The harmful effects of their biological accumulation...
The use of polystyrene micro and nanoplastics in cosmetics and personal care products continues to grow every day. The harmful effects of their biological accumulation in organisms of all trophic levels including humans have been reported by several studies. While we have accumulating evidence on the impact of nanoplastics on different organ systems in humans, only a handful of reports on the impact of polystyrene nanoplastics upon direct contact with the immune system at the cellular level are avialable. The present study offers significant evidence on the cell-specific harmful impact of sulfate-modified nanoplastics (S-NPs) on human macrophages. Here we report that exposure of human macrophages to S-NPs (100 µg/mL) stimulated the accumulation of lipids droplets (LDs) in the cytoplasm resulting in the differentiation of macrophages into foam cells. The observed effect was specific for human and murine macrophages but not for other cell types, especially human keratinocytes, liver, and lung cell models. Furthermore, we found that S-NPs mediated LDs accumulation in human macrophages was accompanied by acute mitochondrial oxidative stress. The accumulated LDs were further delivered and accumulated into lysosomes leading to impaired lysosomal clearance. In conclusion, our study reveals that exposure to polystyrene nanoplastics stabilized with anionic surfactants can be a potent stimulus for dysregulation of lipid metabolism and macrophage foam cell formation, a characteristic feature observed during atherosclerosis posing a serious threat to human health.
Topics: Animals; Atherosclerosis; Humans; Lipid Metabolism; Lysosomes; Macrophages; Mice; Microplastics; Nanoparticles; Polystyrenes
PubMed: 35561548
DOI: 10.1016/j.ecoenv.2022.113612 -
Journal of Hazardous Materials Jul 2023In the era of plastic use, organisms are constantly exposed to polystyrene particles (PS-Ps). PS-Ps accumulated in living organisms exert negative effects on the body,...
In the era of plastic use, organisms are constantly exposed to polystyrene particles (PS-Ps). PS-Ps accumulated in living organisms exert negative effects on the body, although studies evaluating their effects on brain development are scarce. In this study, the effects of PS-Ps on nervous system development were investigated using cultured primary cortical neurons and mice exposed to PS-Ps at different stages of brain development. The gene expression associated with brain development was downregulated in embryonic brains following PS-Ps exposure, and Gabra2 expression decreased in the embryonic and adult mice exposed to PS-Ps. Additionally, offspring of PS-Ps-treated dams exhibited signs of anxiety- and depression-like behavior, and abnormal social behavior. We propose that PS-Ps accumulation in the brain disrupts brain development and behavior in mice. This study provides novel information regarding PS-Ps toxicity and its harmful effects on neural development and behavior in mammals.
Topics: Animals; Mice; Polystyrenes; Depression; Water Pollutants, Chemical; Anxiety; Social Behavior; Nanoparticles; Mammals
PubMed: 37130475
DOI: 10.1016/j.jhazmat.2023.131465 -
Tissue Engineering. Part B, Reviews Oct 2018Polystyrene (PS) has brought in vitro cell culture from its humble beginnings to the modern era, propelling dozens of research fields along the way. This review... (Review)
Review
Polystyrene (PS) has brought in vitro cell culture from its humble beginnings to the modern era, propelling dozens of research fields along the way. This review discusses the development of the material, fabrication, and treatment approaches to create the culture material. However, native PS surfaces poorly facilitate cell adhesion and growth in vitro. To overcome this, liquid surface deposition, energetic plasma activation, and emerging functionalization methods transform the surface chemistry. This review seeks to highlight the many potential applications of the first widely accepted polymer growth surface. Although the majority of in vitro research occurs on two-dimensional surfaces, the importance of three-dimensional (3D) culture models cannot be overlooked. The methods to transition PS to specialized 3D culture surfaces are also reviewed. Specifically, casting, electrospinning, 3D printing, and microcarrier approaches to shift PS to a 3D culture surface are highlighted. The breadth of applications of the material makes it impossible to highlight every use, but the aim remains to demonstrate the versatility and potential as both a general and custom cell culture surface. The review concludes with emerging scaffolding approaches and, based on the findings, presents our insights on the future steps for PS as a tissue culture platform.
Topics: Animals; Cell Adhesion; Cell Culture Techniques; Humans; Polymers; Polystyrenes; Printing, Three-Dimensional; Tissue Engineering
PubMed: 29631491
DOI: 10.1089/ten.TEB.2018.0056 -
Nature Communications Mar 2020Conducting polymers are promising material candidates in diverse applications including energy storage, flexible electronics, and bioelectronics. However, the...
Conducting polymers are promising material candidates in diverse applications including energy storage, flexible electronics, and bioelectronics. However, the fabrication of conducting polymers has mostly relied on conventional approaches such as ink-jet printing, screen printing, and electron-beam lithography, whose limitations have hampered rapid innovations and broad applications of conducting polymers. Here we introduce a high-performance 3D printable conducting polymer ink based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) for 3D printing of conducting polymers. The resultant superior printability enables facile fabrication of conducting polymers into high resolution and high aspect ratio microstructures, which can be integrated with other materials such as insulating elastomers via multi-material 3D printing. The 3D-printed conducting polymers can also be converted into highly conductive and soft hydrogel microstructures. We further demonstrate fast and streamlined fabrications of various conducting polymer devices, such as a soft neural probe capable of in vivo single-unit recording.
Topics: Elastomers; Electric Conductivity; Electronics; Hydrogels; Ink; Polymers; Polystyrenes; Printing; Printing, Three-Dimensional
PubMed: 32231216
DOI: 10.1038/s41467-020-15316-7 -
Ecotoxicology and Environmental Safety Oct 2023Nanoplastics (NPs) frequently cause adverse health effects by transporting organic pollutants such as dibutyl phthalate (DBP) into organisms by utilizing their large...
Nanoplastics (NPs) frequently cause adverse health effects by transporting organic pollutants such as dibutyl phthalate (DBP) into organisms by utilizing their large specific surface area, large surface charge, and increased hydrophobicity. However, the effects of NPs combined with DBP on the reproductive systems of mammals are still unclear. The present investigation involved the administration of polystyrene NPs (PS-NPs) to BALB/c mice via gavage, with a size of 100 nm and at doses of 5 mg/kg/day or 50 mg/kg/day, along with DBP at a dose of 0.5 mg/kg/day, or a combination of PS-NPs and DBP, for 30 days, to assess their potential for reproductive toxicity. The co-exposure of mice to PS-NPs and DBP resulted in a significant increase in reproductive toxicities compared to exposure to PS-NPs or DBP alone. This was demonstrated by a marked decrease in sperm quality, significant impairment of spermatogenesis, and increased disruption of the blood-testis barrier (BTB). Furthermore, a combination of in vivo and in vitro investigations were conducted to determine that the co-exposure of DBP and PS-NPs resulted in a noteworthy reduction in the expressions of tight junction proteins (ZO-1 and occludin). Moreover, the in vitro findings revealed that monobutyl phthalate (MBP, the active metabolite of DBP, 0.5 μg/mL) and PS-NPs (30 μg/mL or 300 μg/mL) inhibited autophagy in Sertoli cells, thereby increasing the expression of matrix metalloproteinases (MMPs). The study found that PS-NPs and DBP co-exposure caused harmful effects in male reproductive organs by disrupting BTB, which may be alleviated by reactivating autophagy. The paper's conclusions provided innovative perspectives on the collective toxicities of PS-NPs and other emerging pollutants.
Topics: Male; Animals; Mice; Dibutyl Phthalate; Blood-Testis Barrier; Microplastics; Polystyrenes; Semen; Autophagy; Drug-Related Side Effects and Adverse Reactions; Environmental Pollutants; Mice, Inbred BALB C; Mammals
PubMed: 37659273
DOI: 10.1016/j.ecoenv.2023.115403