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Ecotoxicology and Environmental Safety Jun 2024Microplastics (MPs) and okadaic acid (OA) are known to coexist in marine organisms, potentially impacting humans through food chain. However, the combined toxicity of OA...
Microplastics (MPs) and okadaic acid (OA) are known to coexist in marine organisms, potentially impacting humans through food chain. However, the combined toxicity of OA and MPs remains unknown. In this study, mice were orally administered OA at 200 μg/kg bw and MPs at 2 mg/kg bw. The co-exposure group showed a significant increase in malondialdehyde (MDA) content and significant decreases in superoxide dismutase (SOD) activity and glutathione (GSH) level compared to the control, MPs and OA groups (p < 0.05). Additionally, the co-exposure group exhibited significantly higher levels of IL-1β and IL-18 compared to other groups (p < 0.05). These results demonstrated that co-exposure to MPs and OA induces oxidative stress and exacerbates inflammation. Histological and cellular ultrastructure analyses suggested that this combined exposure may enhance gut damage and compromise barrier integrity. Consequently, the concentration of OA in the small intestine of the co-exposure group was significantly higher than that in the OA group. Furthermore, MPs were observed in the lamina propria of the gut in the co-exposure group. Transcriptomic analysis revealed that the co-exposure led to increased expression of certain genes related to the NF-κB/NLRP3 pathway compared to the OA and MPs groups. Overall, this combined exposure may disrupt the intestinal barrier, and promote inflammation through the NF-κB/NLRP3 pathway. These findings provide precious information for the understanding of health risks associated with MPs and phycotoxins.
PubMed: 38905936
DOI: 10.1016/j.ecoenv.2024.116628 -
Ugeskrift For Laeger Jun 2024This is a case report of a 70-year-old woman with possible cholestyramine-induced bowel perforation. She had a prior history of pancreaticoduodenectomy for pancreatic...
This is a case report of a 70-year-old woman with possible cholestyramine-induced bowel perforation. She had a prior history of pancreaticoduodenectomy for pancreatic cancer with a daily intake of cholestyramine. She underwent emergency laparotomy for small bowel perforation twice. Subsequent pathology reports showed crystal depositions in the small bowel wall. Leasions spread out on the small bowel and the omentum during the second surgery were thought to be carcinomatosis. However, the pathology report showed no malignant cells but plenty of crystal depositions as seen with cholestyramine intake.
Topics: Humans; Aged; Female; Intestinal Perforation; Cholestyramine Resin; Intestine, Small; Pancreaticoduodenectomy; Anticholesteremic Agents; Pancreatic Neoplasms
PubMed: 38904283
DOI: 10.61409/V02240109 -
ACS Applied Polymer Materials Jun 2024The processing of an immiscible polymer blend using melt blending (i.e., extrusion) often results in a polymer material with inferior mechanical performance compared...
The processing of an immiscible polymer blend using melt blending (i.e., extrusion) often results in a polymer material with inferior mechanical performance compared with its virgin counterparts. Here, we report and compare the properties of immiscible polymer blends produced from industrial mixed plastic waste from shredder residue comprising at least four different polymers (acrylonitrile butadiene styrene, polystyrene, polypropylene, and polyethylene) and a prior melt-blending step employed. As anticipated, mixed plastic blend produced a prior melt-blending step exhibited a more homogeneous microstructure, resulting in brittleness, poor work of fracture, and single-edge notched fracture toughness with a flat R-curve. Without the intimate polymers mixing arising from melt blending, the resulting mixed plastic blend was found to possess a more heterogeneous concentric ellipsoid microstructure with large single polymer domains. This mixed plastic blend demonstrated progressive failure under uniaxial tensile loading, along with a more ductile single-edge notched fracture toughness response accompanied by a growing R-curve. Digital image correlation and fractographic analysis revealed that melt blending created a large number of incompatible polymer boundaries that acted as stress concentration points, leading to brittleness and earlier onset catastrophic failure. The more heterogeneous mixed plastic blend produced using a prior melt-blending step contains a smaller number of incompatible polymer boundaries. Additionally, the presence of larger single polymer domains also implies that the mechanical characteristics of the single polymer can be exploited in the immiscible mixed plastic blend. Our work opens up a simple pathway to add value to mixed plastic waste from shredder residue for use in engineering applications, diverting them away from landfill or incineration.
PubMed: 38903398
DOI: 10.1021/acsapm.4c00360 -
Scientific Reports Jun 2024Newly synthesized gemini quaternary ammonium salts (QAS) with different counterions (bromide, hydrogen chloride, methylcarbonate, acetate, lactate), chain lengths (C12,...
Newly synthesized gemini quaternary ammonium salts (QAS) with different counterions (bromide, hydrogen chloride, methylcarbonate, acetate, lactate), chain lengths (C12, C14, C16) and methylene linker (3xCH) were tested. Dihydrochlorides and dibromides with 12 carbon atoms in hydrophobic chains were characterized by the highest biological activity against planktonic forms of yeast and yeast-like fungi. The tested gemini surfactants also inhibited the production of filaments by C. albicans. Moreover, they reduced the adhesion of C. albicans cells to the surfaces of stainless steel, silicone and glass, and slightly to polystyrene. In particular, the gemini compounds with 16-carbon alkyl chains were most effective against biofilms. It was also found that the tested surfactants were not cytotoxic to yeast cells. Moreover, dimethylcarbonate (2xCMeCOG) did not cause hemolysis of sheep erythrocytes. Dihydrochlorides, dilactate and diacetate showed no mutagenic potential.
Topics: Biofilms; Quaternary Ammonium Compounds; Antifungal Agents; Candida albicans; Animals; Sheep; Surface-Active Agents; Hemolysis; Erythrocytes; Microbial Sensitivity Tests; Cell Adhesion; Stainless Steel
PubMed: 38898117
DOI: 10.1038/s41598-024-64859-y -
Ecotoxicology and Environmental Safety Jun 2024Arsenic pollution control technology in water was important to ensure environmental health and quality safety of agricultural products. Therefore, the adsorption...
Arsenic pollution control technology in water was important to ensure environmental health and quality safety of agricultural products. Therefore, the adsorption performance of three adsorbents for chitosan, sepiolite, and Zeolitic Imidazolate Framework-8 (ZIF-8) were investigated in arsenate contaminated water. The results revealed that the adsorption capacity of ZIF-8 was higher than that of chitosan and sepiolite. The analysis of adsorption isotherm models showed that the behavior of ZIF-8 was more consistent with the Langmuir model. Furthermore, the adsorption mechanisms of three adsorbents for arsenate were investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The analysis of FTIR showed that ZIF-8 maintained the stability of the interaction with arsenate by forming As-O chemical bonds. However, the effect of chitosan and sepiolite with arsenate was mainly physical adsorption. The analysis of XPS showed that the absorption of ZIF-8 with arsenate involved metal sites and nitrogen through the characteristic peak and the change of the binding energy. Furthermore, the impact of microplastics as a widespread coexistence pollutant in the water on adsorbent performance was investigated. The results indicated that the adsorption capacity of ZIF-8 was almost not affected by microplastics. The maximum adsorption amount of arsenate was changed from 73.45 mg/g to 81.89 mg/g. However, the maximum adsorption amount of chitosan and sepiolite decreased by 31.4 % and 11.6 %, respectively. The analysis of FTIR and XPS revealed that ZIF-8 enhances arsenate adsorption by forming N-O-As bonds in the presence of microplastics. This study provides scientific evidence for the management of arsenate pollution in water bodies, especially in complex water bodies containing microplastics.
PubMed: 38896901
DOI: 10.1016/j.ecoenv.2024.116600 -
Sensors (Basel, Switzerland) May 2024Circulating tumor cells are typically found in the peripheral blood of patients, offering a crucial pathway for the early diagnosis and prediction of cancer. Traditional...
Circulating tumor cells are typically found in the peripheral blood of patients, offering a crucial pathway for the early diagnosis and prediction of cancer. Traditional methods for early cancer diagnosis are inefficient and inaccurate, making it difficult to isolate tumor cells from a large number of cells. In this paper, a new spiral microfluidic chip with asymmetric cross-section is proposed for rapid, high-throughput, label-free enrichment of CTCs in peripheral blood. A mold of the desired flow channel structure was prepared and inverted to make a trapezoidal cross-section using a micro-nanotechnology process of 3D printing. After a systematic study of how flow rate, channel width, and particle concentration affect the performance of the device, we utilized the device to simulate cell sorting of 6 μm, 15 μm, and 25 μm PS (Polystyrene) particles, and the separation efficiency and separation purity of 25 μm PS particles reached 98.3% and 96.4%. On this basis, we realize the enrichment of a large number of CTCs in diluted whole blood (5 mL). The results show that the separation efficiency of A549 was 88.9% and the separation purity was 96.4% at a high throughput of 1400 μL/min. In conclusion, we believe that the developed method is relevant for efficient recovery from whole blood and beneficial for future automated clinical analysis.
Topics: Humans; Cell Separation; Neoplastic Cells, Circulating; Lab-On-A-Chip Devices; A549 Cells; Microfluidic Analytical Techniques; Printing, Three-Dimensional
PubMed: 38894343
DOI: 10.3390/s24113552 -
Sensors (Basel, Switzerland) May 2024We present a goniometer designed for capturing spectral and angular-resolved data from scattering and absorbing media. The experimental apparatus is complemented by a...
We present a goniometer designed for capturing spectral and angular-resolved data from scattering and absorbing media. The experimental apparatus is complemented by a comprehensive Monte Carlo simulation, meticulously replicating the radiative transport processes within the instrument's optical components and simulating scattering and absorption across arbitrary volumes. Consequently, we were able to construct a precise digital replica, or "twin", of the experimental setup. This digital counterpart enabled us to tackle the inverse problem of deducing optical parameters such as absorption and scattering coefficients, along with the scattering anisotropy factor from measurements. We achieved this by fitting Monte Carlo simulations to our goniometric measurements using a Levenberg-Marquardt algorithm. Validation of our approach was performed using polystyrene particles, characterized by Mie scattering, supplemented by a theoretical analysis of algorithmic convergence. Ultimately, we demonstrate strong agreement between optical parameters derived using our novel methodology and those obtained via established measurement protocols.
PubMed: 38894316
DOI: 10.3390/s24113525 -
Materials (Basel, Switzerland) Jun 2024Poly(9,9-di--octylfluorene) (PFO) is a promising material for polymer light-emitting diodes (PLEDs) due to its advantageous properties. To enhance its electron...
Poly(9,9-di--octylfluorene) (PFO) is a promising material for polymer light-emitting diodes (PLEDs) due to its advantageous properties. To enhance its electron transporting capabilities, diblock polymers were synthesized by attaching polystyrene (PSt) chains of varying lengths to one end of the PFO molecule. In a comparative study with PFO homopolymer, the diblock polymers maintained similar thermal properties, absorption spectra, and photoluminescent stability, while exhibiting slightly deeper lowest unoccupied molecular orbital (LUMO) levels and higher crystallinity. Notably, diblock polymers with shorter polystyrene blocks demonstrated higher electron mobility than the PFO homopolymer and diblock polymers with excessively long polystyrene blocks. These findings suggest that the optimal chain length of the polystyrene block is crucial for maximizing electron mobility, thus offering valuable insights for designing high-performance PLED materials.
PubMed: 38893958
DOI: 10.3390/ma17112694 -
Materials (Basel, Switzerland) Jun 2024Polymer waste is currently a big and challenging issue throughout the world. Waste tires represent an important source of polymer waste. Therefore, it is highly... (Review)
Review
Recycling Functional Fillers from Waste Tires for Tailored Polystyrene Composites: Mechanical, Fire Retarding, Electromagnetic Field Shielding, and Acoustic Insulation Properties-A Short Review.
Polymer waste is currently a big and challenging issue throughout the world. Waste tires represent an important source of polymer waste. Therefore, it is highly desirable to recycle functional fillers from waste tires to develop composite materials for advanced applications. The primary theme of this review involves an overview of developing polystyrene (PS) composites using materials from recycled tires as fillers; waste tire recycling in terms of ground tire rubbers, carbon black, and textile fibers; surface treatments of the fillers to optimize various composite properties; and the mechanical, fire retarding, acoustic, and electromagnetic field (EMI) shielding performances of PS composite materials. The development of composite materials from polystyrene and recycled waste tires provides a novel avenue to achieve reductions in carbon emission goals and closed-loop plastic recycling, which is of significance in the development of circular economics and an environmentally friendly society.
PubMed: 38893939
DOI: 10.3390/ma17112675 -
Materials (Basel, Switzerland) May 2024As an important part of head protection equipment, research on the material and structural application of helmet liners has always been one of the hotspots in the field... (Review)
Review
As an important part of head protection equipment, research on the material and structural application of helmet liners has always been one of the hotspots in the field of helmets. This paper first discusses common helmet liner materials, including traditional polystyrene, polyethylene, polypropylene, etc., as well as newly emerging anisotropic materials, polymer nanocomposites, etc. Secondly, the design concept of the helmet liner structure is discussed, including the use of a multi-layer structure, the addition of geometric irregular bubbles to enhance the energy absorption effect, and the introduction of new manufacturing processes, such as additive manufacturing technology, to realize the preparation of complex structures. Then, the application of biomimetic structures to helmet liner design is analyzed, such as the design of helmet liner structures with more energy absorption properties based on biological tissue structures. On this basis, we propose extending the concept of bionic structural design to the fusion of plant stalks and animal skeletal structures, and combining additive manufacturing technology to significantly reduce energy loss during elastic yield energy absorption, thus developing a reusable helmet that provides a research direction for future helmet liner materials and structural applications.
PubMed: 38893913
DOI: 10.3390/ma17112649