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Chemical Research in Toxicology Jun 2021High concentrations of micro- and nanoparticles of common plastic materials present in the environment are causing an adverse health impact on living organisms. As a... (Comparative Study)
Comparative Study
High concentrations of micro- and nanoparticles of common plastic materials present in the environment are causing an adverse health impact on living organisms. As a model study, here we report the synthesis and characterization of luminescent polyvinyl chloride (PVC) and poly(methyl methacrylate) (PMMA) nanoparticles and investigate the interaction with normal human lung fibroblast cells (IMR 90) to understand the uptake, translocation, and toxicity of PVC and PMMA nanoparticles. The synthesized particles are in the size range of 120-140 nm with a negative surface potential. The colocalization and uptake efficiency of the nanoparticles were analyzed, and the cytotoxicity assay shows significant reduction in cell viability. Cellular internalization was investigated using colocalization and dynasore inhibitor tests, which showed that the PVC and PMMA nanoparticles enter into the cell via endocytosis. The polymer nanoparticles induced a reduction in viability, decrease in adenosine triphosphate, and increase in reactive oxygen species and lactate dehydrogenase concentrations. In addition, the polymer nanoparticles caused cell cycle arrest at sub-G, G/G, and G2/M phases, followed by apoptotic cell death. Our results reported here are important to the emerging data on understanding the impact of common polymer particles on human health.
Topics: Cell Cycle Checkpoints; Cell Death; Cell Survival; Cells, Cultured; Humans; Nanoparticles; Particle Size; Polymethyl Methacrylate; Polyvinyl Chloride
PubMed: 33861932
DOI: 10.1021/acs.chemrestox.0c00391 -
Angewandte Chemie (International Ed. in... Feb 2023Commercially available stock solutions of organolithium reagents are well-implemented tools in organic and organometallic chemistry. However, such solutions are...
Commercially available stock solutions of organolithium reagents are well-implemented tools in organic and organometallic chemistry. However, such solutions are inherently contaminated with lithium halide salts, which can complicate certain synthesis protocols and purification processes. Here, we report the isolation of chloride-free methyllithium employing K[N(SiMe ) ] as a halide-trapping reagent. The influence of distinct LiCl contaminations on the Li-NMR chemical shift is examined and their quantification demonstrated. The structural parameters of new chloride-free monomeric methyllithium complex [(Me TACN)LiCH ], ligated by an azacrown ether, are assessed by comparison with a halide-contaminated variant and monomeric lithium chloride [(Me TACN)LiCl], further emphasizing the effect of halide impurities.
PubMed: 36409199
DOI: 10.1002/anie.202214599 -
Chemical & Pharmaceutical Bulletin 2023Benzalkonium chloride (BAC) is a useful preservative for ophthalmic solutions but has some disadvantageous effects on corneal epithelium, especially keratinocytes....
Benzalkonium chloride (BAC) is a useful preservative for ophthalmic solutions but has some disadvantageous effects on corneal epithelium, especially keratinocytes. Therefore, patients requiring the chronic administration of ophthalmic solutions may suffer from damage due to BAC, and ophthalmic solutions with a new preservative instead of BAC are desired. To resolve the above situation, we focused on 1,3-didecyl-2-methyl imidazolium chloride (DiMI). As a preservative for ophthalmic solutions, we evaluated the physical and chemical properties (absorption to a sterile filter, solubility, heat stress stability, and light/UV stress stability), and also the anti-microbial activity. The results indicated that DiMI was soluble enough to prepare ophthalmic solutions, and was stable under severe heat and light/UV conditions. In addition, the anti-microbial effect of DiMI as a preservative was considered to be stronger than BAC. Moreover, our in vitro toxicity tests suggested that DiMI is safer to humans than BAC. Considering the test results, DiMI may be an excellent candidate for a new preservative to replace BAC. If we can overcome manufacturing process issues (soluble time and flushing volume) and the insufficiency of toxicological information, DiMI may be widely adopted as a safe preservative, and immediately contribute to the increased well-being of all patients.
Topics: Humans; Benzalkonium Compounds; Ophthalmic Solutions; Preservatives, Pharmaceutical; Epithelium, Corneal
PubMed: 37394604
DOI: 10.1248/cpb.c23-00115 -
ACS Omega May 2023In this paper, a series of energetic ionic liquid plasticizers of 1-methyl-4-methoxyethyl-1,2,4-triazolium chloride (), 1-methyl-4-methoxyethyl-1,2,4-triazolium...
In this paper, a series of energetic ionic liquid plasticizers of 1-methyl-4-methoxyethyl-1,2,4-triazolium chloride (), 1-methyl-4-methoxyethyl-1,2,4-triazolium bis(trifluoromethylsulfonyl)imide (), 1-methyl-4-methoxyethyl-1,2,4-triazolium nitrate (), 1-methyl-4-ethyl acetate-1,2,4-triazolium chloride (), 1-methyl-4-ethyl acetate-1,2,4-triazolium bis(trifluoromethylsulfonyl)imide (), and 1-methyl-4-ethyl acetate-1,2,4-triazolium nitrate () were synthesized and characterized. The results show that compounds , , , and have lower melting points (, -72.60 to -32.67 °C) and good thermal stability (, 161-348 °C) and are suitable as plasticizers for hydroxyl-terminated polybutadiene (HTPB) curing systems. Among these four ionic liquids, ester-functionalized cations can help to improve the tensile strength (, 0.943 MPa; , 1.113 MPa) of the cured system, while ether-functionalized cations are more beneficial to improve elongation at break (, 522.90%; , 484.45%). Ester-functionalized ionic liquids are more beneficial to reduce the glass transition temperature of HTPB elastomers. The storage modulus of HTPB elastomers containing NO is higher, while that of HTPB elastomers containing NTf is lower. The crosslink densities of HTPB/TDI/ and HTPB/TDI/ plasticized by ester-functionalized ionic liquids are larger, which are 9369 and 9616 mol/m, respectively. There are hydrogen bond interactions between the ionic liquid and the HTPB elastomer, and these interactions changed the distribution of the hard and soft segments in the polymer molecules.
PubMed: 37214713
DOI: 10.1021/acsomega.3c00256 -
Scientific Reports Jan 2021Microplastic and nanoplastic particles are prevalent in the environment and are beginning to enter the living system through multiple channels. Currently, little is...
Microplastic and nanoplastic particles are prevalent in the environment and are beginning to enter the living system through multiple channels. Currently, little is known about the impact of plastic nanoparticles in living organisms. In order to investigate the health impact of micro- and nanoparticles of common polymers in a systematic way, luminescent plastic nanoparticles from two common polymers, polyvinyl chloride (PVC) and poly (methyl methacrylate) (PMMA) with relatively narrow size distribution are prepared using a nanoprecipitation method. As a model system, BHK-21 cells were exposed to polymer nanoparticles to understand the mode of uptake, internalization and biochemical changes inside the cells. The cellular effects of the nanoparticles were evaluated by monitoring the changes in cell viability, cell morphology, concentrations of reactive oxygen species (ROS), adenine triphosphate (ATP) and lactate dehydrogenase at different concentrations of the nanoparticles and time of exposure. PVC and PMMA nanoparticles induced a reduction in the cell viability along with a reduction of ATP and increase of ROS concentrations in a dose- and time-dependent manner. The plastic nanoparticles are internalized into the cell via endocytosis, as confirmed by Dynasore inhibition assay and colocalization with latex beads. Our findings suggest that plastic nanoparticle internalization could perturb cellular physiology and affect cell survival under laboratory conditions.
Topics: Adenosine Triphosphate; Animals; Cell Cycle; Cell Line; Cricetinae; Endocytosis; Kidney; L-Lactate Dehydrogenase; Microscopy, Electron, Scanning; Nanoparticles; Polymethyl Methacrylate; Polyvinyl Chloride; Reactive Oxygen Species
PubMed: 33483569
DOI: 10.1038/s41598-020-80708-0 -
Journal of Biochemical and Molecular... Sep 2022The objective of this study was to examine the protective effects of S-methyl methionine sulfonium chloride (MMSC) against galactosamine (GalN)-induced brain and...
The objective of this study was to examine the protective effects of S-methyl methionine sulfonium chloride (MMSC) against galactosamine (GalN)-induced brain and cerebellum injury in rats. A total of 22 female Sprague-Dawley rats were randomly divided into four groups as follows: Group I (n = 5), intact animals; Group II (n = 6), animals received 50 mg/kg/day of MMSC by gavage technique for 3 consecutive days; Group III (n = 5), animals injected with a single dose of 500 mg/kg of GalN intraperitoneally (ip); and Group IV (n = 6), animals injected with the same dose of GalN 1 h after MMSC treatment. After 6 h of the last GalN treatment (at the end of the experiments), all animals were killed under anesthesia, brain and cerebellum tissues were dissected out. Reduced glutathione, total antioxidant status levels, and antioxidant enzymes (catalase, superoxide dismutase, and glutathione-related enzymes), aryl esterase, and carbonic anhydrase activities remarkably declined whereas advanced oxidized protein products, reactive oxygen species, total oxidant status, oxidative stress index levels, and myeloperoxidase, acetylcholinesterase, lactate dehydrogenase, and xanthine oxidase activities were significantly elevated in the GalN group compared with intact rats. In contrast, the administration of MMSC to GalN groups reversed these alterations. In conclusion, we may suggest that MMSC has protective effects against GalN-induced brain and cerebellar toxicity in rats.
Topics: Acetylcholinesterase; Animals; Antioxidants; Brain; Carbonic Anhydrases; Catalase; Cerebellum; Chemical and Drug Induced Liver Injury; Chlorides; Female; Galactosamine; Glutathione; Lactate Dehydrogenases; Methionine; Oxidants; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Sulfonium Compounds; Superoxide Dismutase; Vitamin U; Xanthine Oxidase
PubMed: 35673974
DOI: 10.1002/jbt.23126 -
The Journal of Physical Chemistry. A Nov 2021The structure and spectroscopy of the anion of oxalyl chloride are investigated using photoelectron imaging experiments and ab initio modeling. The photoelectron images,...
The structure and spectroscopy of the anion of oxalyl chloride are investigated using photoelectron imaging experiments and ab initio modeling. The photoelectron images, spectra, and angular distributions are obtained at 355 and 532 nm wavelengths. The 355 nm spectrum consists of a band assigned to a transition from the ground state of the anion to the ground state of the neutral. Its onset at ∼1.8 eV corresponds to the adiabatic electron affinity (EA) of oxalyl chloride, in agreement with the coupled-cluster calculations predicting an EA of 1.797 eV. The observed vertical detachment energy, 2.33(4) eV, is also in agreement with the theory predictions. The 532 nm spectrum additionally reveals a sharp onset near the photon-energy limit. This feature is ascribed to autodetachment via a low-energy anionic resonance. The results are discussed in the context of the substitution series, which includes glyoxal, methylglyoxal (single methyl substitution), biacetyl (double methyl substitution), and oxalyl chloride (double chlorine substitution). The EAs and anion detachment energies follow the trend: biacetyl < methylglyoxal < glyoxal ≪ oxalyl chloride. The electron-donating character of the methyl group has a destabilizing effect on the substituted anions, reducing the EA from glyoxal to methylglyoxal to biacetyl. In contrast, the strong electron-withdrawing (inductive) power of Cl lends additional stabilization to the oxalyl chloride anion, resulting in a large (∼1 eV) increase in its detachment energy compared to glyoxal.
PubMed: 34732045
DOI: 10.1021/acs.jpca.1c07451 -
Physiology and Molecular Biology of... Feb 2023L., is a sprawling, leafy herb that grows in open, disturbed areas, known as St. John's wort, has a variety of secondary metabolites that can be used for medicinal and...
Investigation of the combined effects of cadmium chloride, silver nitrate, lead nitrate, methyl jasmonate, and salicylic acid on morphometric and biochemical characteristics of St. John's wort.
L., is a sprawling, leafy herb that grows in open, disturbed areas, known as St. John's wort, has a variety of secondary metabolites that can be used for medicinal and therapeutic purposes. Heavy metals have become the most dangerous pollutants in the environment. The effect of cadmium chloride, lead nitrate, silver nitrate, methyl jasmonate, and salicylic acid was studied on several morphometric and biochemical features of St. John's wort simultaneously using the Taguchi statistical method. The results showed cadmium chloride and lead nitrate reduced the morphometric and biochemical properties of St. John's wort while salicylic acid compensated for the adverse effects of heavy metals. Simultaneously, use of salicylic acid and silver nitrate with cadmium chloride and lead nitrate reduced the toxic effects of these metals on morphometric properties. Methyl jasmonate improved growth characteristics at low levels and inhibited at higher levels. Also, according to the results, salicylic acid could reduce the effects of heavy metals on the biochemical properties, while silver nitrate acts like heavy metals, especially at higher levels. Salicylic acid reduced the harmful effects of these heavy metals and at all levels was able to create a better induction effect on St. John's wort. These elicitors mainly changed the adverse effects of heavy metals by strengthening the pathways of the antioxidant system in St. John's wort. The research assumptions were validated, which suggests that the Taguchi method could be considered in an optimum culture of medicinal plants under different treatments such as heavy metals and elicitors.
PubMed: 36875733
DOI: 10.1007/s12298-023-01281-0 -
International Journal of Environmental... Sep 2021Liver disease, especially liver cancer, has become a threat facing the world. Now, antioxidant products are garnering great attention for the treatment and prevention of...
Antitumor and Antioxidant Activity of S-Methyl Methionine Sulfonium Chloride against Liver Cancer Induced in Wistar Albino Rats by Diethyl Nitrosamine and Carbon Tertrachloride.
Liver disease, especially liver cancer, has become a threat facing the world. Now, antioxidant products are garnering great attention for the treatment and prevention of many diseases. S-Methyl methionine sulfonium chloride (MMSC) is a methionine derivative and is present in many vegetables and has anti-inflammatory effects and antioxidants. This is the first study aiming to investigate the antitumor activity of the MMSC. This study was carried out on 60 male Wistar albino rats (4-6 weeks old age) and divided into four groups, with the first group as normal control, second group as hepatocarcinoma induced by diethyl nitrosamine and carbon tetrachloride (DEN/CCL4) group, third group as normal rats treated with MMSC, and fourth group as hepatocellular carcinoma (HCC) induced rats treated with MMSC. Our findings revealed that MMSC administration after HCC induction significantly improved ( < 0.05) the liver function biomarkers, including AST, GGT, albumin, globulin, and albumin/globulin ratio (A/G), in comparison with those in the HCC group. Moreover, the histopathological changes of the liver tissue in the HCC group were improved by MMSC treatment. Likewise, the expression levels of tumor necrosis factor-alpha (), induced nitric oxide synthase (), transforming growth factor (), and glypican 3 () were downregulated by MMSC treatment after HCC induction in comparison with those in the HCC-induced group. In conclusion, MMSC showed antitumor activity against HCC induction by DEN/CCl4 through decreasing lipid peroxide formation, the expression level of an inflammatory cytokines such as (), immunoregulatory cytokines such as (), induced nitric oxide synthase, and glypican 3.
Topics: Animals; Antioxidants; Carbon; Carcinoma, Hepatocellular; Chlorides; Diethylnitrosamine; Liver; Liver Neoplasms; Male; Methionine; Rats; Rats, Wistar; Vitamin U
PubMed: 34574650
DOI: 10.3390/ijerph18189726 -
Journal of Hazardous Materials Feb 2020Ultraviolet (UV) irradiation is widely used for water treatment due to its effectiveness against a wide range of waterborne pathogens with minimal production of...
Ultraviolet (UV) irradiation is widely used for water treatment due to its effectiveness against a wide range of waterborne pathogens with minimal production of regulated disinfection byproducts. However, in this study, the formation of methyl chloride (CHCl) from guaiacol and chloride was observed during UV irradiation. The results indicated that direct photolysis of guaiacol produced an arenium ion, and the reactive methoxy group was further transformed to CHCl in the presence of chloride. O-quinone was detected as the primary product of the degradation of guaiacol resulting from UV irradiation. Other organic compounds containing methoxy, ethoxy, or methylamino groups with structures that are similar to guaiacol were also demonstrated to generate halocarbons in aqueous chloride or bromide solution under UV irradiation. Scavenging experiments and removal of oxygen demonstrated that neither oxygen nor chlorine radicals were involved in CHCl formation. In seawater samples, CHCl was also detected in the presence or absence of added organic matter. These results demonstrate that CHCl can be formed during UV irradiation in saline water and that attention should be paid to this compound and structurally-related compounds in the application of UV processes.
PubMed: 31605974
DOI: 10.1016/j.jhazmat.2019.121263