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1.
Arch Microbiol ; 206(7): 328, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935150

RESUMEN

Marine hydrocarbonoclastic bacteria can use polycyclic aromatic hydrocarbons as carbon and energy sources, that makes these bacteria highly attractive for bioremediation in oil-polluted waters. However, genomic and metabolic differences between species are still the subject of study to understand the evolution and strategies to degrade PAHs. This study presents Rhodococcus ruber MSA14, an isolated bacterium from marine sediments in Baja California, Mexico, which exhibits adaptability to saline environments, a high level of intrinsic pyrene tolerance (> 5 g L- 1), and efficient degradation of pyrene (0.2 g L- 1) by 30% in 27 days. Additionally, this strain demonstrates versatility by using naphthalene and phenanthrene as individual carbon sources. The genome sequencing of R. ruber MSA14 revealed a genome spanning 5.45 Mbp, a plasmid of 72 kbp, and three putative megaplasmids, lengths between 110 and 470 Kbp. The bioinformatics analysis of the R. ruber MSA14 genome revealed 56 genes that encode enzymes involved in the peripheral and central pathways of aromatic hydrocarbon catabolism, alkane, alkene, and polymer degradation. Within its genome, R. ruber MSA14 possesses genes responsible for salt tolerance and siderophore production. In addition, the genomic analysis of R. ruber MSA14 against 13 reference genomes revealed that all compared strains have at least one gene involved in the alkanes and catechol degradation pathway. Overall, physiological assays and genomic analysis suggest that R. ruber MSA14 is a new haloalkalitolerant and hydrocarbonoclastic strain toward a wide range of hydrocarbons, making it a promising candidate for in-depth characterization studies and bioremediation processes as part of a synthetic microbial consortium, as well as having a better understanding of the catabolic potential and functional diversity among the Rhodococci group.


Asunto(s)
Biodegradación Ambiental , Genoma Bacteriano , Genómica , Sedimentos Geológicos , Hidrocarburos Policíclicos Aromáticos , Rhodococcus , Rhodococcus/genética , Rhodococcus/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Sedimentos Geológicos/microbiología , Naftalenos/metabolismo , Filogenia , Fenantrenos/metabolismo , Tolerancia a la Sal , Pirenos
2.
J Toxicol Environ Health B Crit Rev ; 27(5-6): 212-232, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-38845364

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants of significant public health concern, with several that are highly toxic to humans, including some proven or suspected carcinogens. To account for the high variability of PAH mixtures encountered in occupational settings, adjusting urinary 1-hydroxypyrene (1-OHP) levels by the total airborne pyrene (PyrT)/benzo[a]pyrene (BaP) ratio is essential for human biomonitoring (HBM). Given the complexity and cost of systematically monitoring atmospheric levels, alternative approaches to simultaneous airborne and HBM are required. The aim of this review was to catalog airborne PyrT/BaP ratios measured during different industrial activities and recommend 1-OHP-dedicated biological guidance values (BGV). A literature search was conducted. Seventy-one studies were included, with 5619 samples pertaining to 15 industrial sectors, 79 emission processes, and 213 occupational activities. This review summarized more than 40 years of data from almost 20 countries and highlighted the diversity and evolution of PAH emissions. PyrT/BaP ratios were highly variable, ranging from 0.8 in coke production to nearly 40 in tire and rubber production. A single PyrT/BaP value cannot apply to all occupational contexts, raising the question of the relevance of defining a single biological limit value for 1-OHP in industrial sectors where the PyrT/BaP ratio variability is high. Based upon the inventory, a practical approach is proposed for systematic PAH exposure and risk assessment, with a simple frame to follow based upon specific 1-OHP BGVs depending upon the occupational context and setup of a free PAH HBM interactive tool.


Asunto(s)
Contaminantes Atmosféricos , Benzo(a)pireno , Monitoreo Biológico , Pirenos , Pirenos/análisis , Pirenos/orina , Humanos , Benzo(a)pireno/análisis , Monitoreo Biológico/métodos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Exposición Profesional/análisis , Industrias
3.
Environ Geochem Health ; 46(7): 225, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849628

RESUMEN

In this study, the freshwater microalgae Selenastrum sp. was assessed for the effective degradation of pyrene and simultaneous production of biodiesel from pyrene-tolerant biomass. The growth of algae was determined based on the cell dry weight, cell density, chlorophyll content, and biomass productivity under different pyrene concentrations. Further, lipids from pyrene tolerant culture were converted into biodiesel by acid-catalyzed transesterification, which was characterized for the total fatty acid profile by gas chromatography. Increased pyrene concentration revealed less biomass yield and productivity after 20 days of treatment, indicating potent pyrene biodegradation by Selenastrum sp. Biomass yield was unaffected till the 20 mg/L pyrene. A 95% of pyrene bioremediation was observed at 20 days of culturing. Lipid accumulation of 22.14%, as evident from the estimation of the total lipid content, indicated a marginal increase in corroborating pyrene stress in the culture. Fatty acid methyl esters yield of 63.06% (% per 100 g lipids) was noticed from the pyrene tolerant culture. Moreover, fatty acid profile analysis of biodiesel produced under 10 mg/L and 20 mg/L pyrene condition showed escalated levels of desirable fatty acids in Selenastrum sp., compared to the control. Further, Selenastrum sp. and other freshwater microalgae are catalogued for sustainable development goals attainment by 2030, as per the UNSDG (United Nations Sustainable Development Goals) agenda. Critical applications for the Selenastrum sp. in bioremediation of pyrene, along with biodiesel production, are enumerated for sustainable and renewable energy production and resource management.


Asunto(s)
Biodegradación Ambiental , Biocombustibles , Biomasa , Agua Dulce , Microalgas , Pirenos , Pirenos/metabolismo , Microalgas/metabolismo , Ácidos Grasos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Clorofila/metabolismo
4.
J Environ Manage ; 363: 121419, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38852405

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) were frequently found in sediment and were primarily treated through microbial degradation. Thus, efficient management of PAH pollution requires exploring the molecular degradation mechanisms of PAHs and expanding the pool of available microbial resources. A fungus (identified as Sarocladium terricola strain RCEF778) with the remarkable ability to degrade pyrene was screened from sediment near a petrochemical plant, and its growth and pyrene degradation characteristics were comprehensively investigated. The results showed that the fungus exhibited great effectiveness in pyrene degradation, with a degradation ratio of 88.97% at 21 days at the conditions: 35 °C, pH 7, 10 mg L-1 initially pyrene concentration, 3% supplementary salt, and glucose supplementation. The generation and concentration variation of the intermediate products were identified, and the results revealed that the fungus degraded pyrene through two pathways: by salicylic acid and by phthalic acid. Three sediments (M1, M2, M3), each exhibiting different levels of PAH pollution, were employed to examine the effectiveness of fungal degradation of PAHs in practical sediment samples. These data showed that with the fungus, the degradation ratios ranged from 13.64% to 23.50% for 2-3 rings PAHs, 40.93%-49.41% for 4 rings PAHs, and 39.59%-48.07% for 5-6 rings PAHs, which were significantly higher than those for the sediment without the fungus and confirmed the excellent performance of the fungal. Moreover, the Gompertz model was employed to analyze the degradation kinetics of 4-rings and 5-6 rings PAHs in these sediments, and the results demonstrated that the addition of the fungus could significantly increase the maximum degradation ratio, degradation start-up rate and maximum degradation rate of 4-rings and 5-6 rings PAHs and shorten the time required to reach the maximum degradation rate. This study not only supplied fungal materials but also established crucial theoretical foundations for the development of bioremediation technologies aimed at high molecular weight PAH-contaminated sediments.


Asunto(s)
Biodegradación Ambiental , Sedimentos Geológicos , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/metabolismo , Sedimentos Geológicos/microbiología , Pirenos/metabolismo
5.
ACS Appl Mater Interfaces ; 16(24): 31610-31623, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38853366

RESUMEN

Affinity-based electrochemical (AEC) biosensors have gained more attention in the field of point-of-care management. However, AEC sensing is hampered by biofouling of the electrode surface and degradation of the antifouling material. Therefore, a breakthrough in antifouling nanomaterials is crucial for the fabrication of reliable AEC biosensors. Herein, for the first time, we propose 1-pyrenebutyric acid-functionalized MXene to develop an antifouling nanocomposite to resist biofouling in the immunosensors. The nanocomposite consisted of a 3D porous network of bovine serum albumin cross-linked with glutaraldehyde with functionalized MXene as conductive nanofillers, where the inherited oxidation resistance property of functionalized MXene improved the electrochemical lifetime of the nanocomposite. On the other hand, the size-extruded porous structure of the nanocomposite inhibited the biofouling activity on the electrode surface for up to 90 days in real samples. As a proof of concept, the antifouling nanocomposite was utilized to fabricate a multiplexed immunosensor for the detection of C-reactive protein (CRP) and ferritin biomarkers. The fabricated sensor showed good selectivity over time and an excellent limit of detection for CRP and ferritin of 6.2 and 4.2 pg/mL, respectively. This research successfully demonstrated that functionalized MXene-based antifouling nanocomposites have great potential to develop high-performance and low-cost immunosensors.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Nanocompuestos , Albúmina Sérica Bovina , Nanocompuestos/química , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Porosidad , Albúmina Sérica Bovina/química , Incrustaciones Biológicas/prevención & control , Proteína C-Reactiva/análisis , Inmunoensayo/métodos , Humanos , Pirenos/química , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/química , Animales , Límite de Detección , Electrodos , Bovinos
6.
J Hazard Mater ; 475: 134911, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38889457

RESUMEN

1-Nitropyrene (1-NP) is a neurodevelopmental toxicant. This study was to evaluate the impact of exposure to 1-NP after weaning on anxiety-like behavior. Five-week-old mice were administered with 1-NP (0.1 or 1 mg/kg) daily for 4 weeks. Anxiety-like behaviour was measured using elevated-plus maze (EPM) and open field test (OFT). In EPM test, time spending in open arm and times entering open arm were reduced in 1-NP-treated mice. In OFT test, time spent in the center region and times entering the center region were diminished in 1-NP-treated mice. Prefrontal dendritic length and number of dendrite branches were decreased in 1-NP-treated mice. Prefrontal PSD95, an excitatory postsynaptic membrane protein, and gephyrin, an inhibitory postsynaptic membrane protein, were downregulated in 1-NP-treated mice. Further analysis showed that peripheral steroid hormones, including serum testosterone (T) and estradiol (E2), testicular T, and ovarian E2, were decreased in 1-NP-treated mice. Interestingly, T and E2 were diminished in 1-NP-treated prefrontal cortex. Prefrontal T and E2 synthases were diminished in 1-NP-treated mice. Mechanistically, GCN2-eIF2α, a critical pathway that regulates ribosomal protein translation, was activated in 1-NP-treated prefrontal cortex. These results indicate that exposure to 1-NP after weaning induces anxiety-like behaviour partially by inhibiting steroid hormone synthesis in prefrontal cortex.


Asunto(s)
Ansiedad , Corteza Prefrontal , Pirenos , Destete , Animales , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Ansiedad/inducido químicamente , Masculino , Pirenos/toxicidad , Femenino , Ratones , Conducta Animal/efectos de los fármacos , Testosterona/sangre , Estradiol
7.
Anal Chem ; 96(25): 10365-10372, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38869249

RESUMEN

Biomimetic cytochrome P450 for chemical activation of environmental carcinogens is an efficient in vitro model for evaluating their mutagenicity and ultimately acquiring the metabolites that cannot be easily accessed by conventional routes of organic synthesis. Different kinds of mutagen derived from polyaromatic hydrocarbons (PAHs) by metalloporphyrin/oxidant model systems have been reported, but the underlying molecular mechanisms are poorly understood. Herein, we have for the first time demonstrated an effective surface-enhanced Raman scattering (SERS) protocol to study the dynamics and biomimetic metabolic behaviors of pyrene (Pyr) in the presence of various oxygen donors. Quantitative information on the relative concentration of Pyr and its metabolites in the biomimetic system can be extracted from the SERS spectra. On the basis of our results, we conclude that the oxidative metabolism of Pyr is highly influenced by the types and concentrations of oxygen donors, leading to the formation of 1-hydroxypyrene and dioxygenated products. Besides, the addition of an appropriate amount of an organic solvent can promote the formation of secondary oxidation products. These results offer valuable insights into the dynamics of PAHs metabolism and the regulation of their metabolic pathways in biomimetic activation. In comparison to traditional liquid chromatography-mass spectrometry, the present SERS approach is more suitable for high-throughput evaluation of the metabolic process and kinetics of PAHs. We anticipate that this approach will enable a more general and comprehensive tracking of metabolic dynamics and molecular mechanisms involved in the biomimetic activation of other xenobiotics, such as procarcinogens, promutagens, and drugs.


Asunto(s)
Pirenos , Espectrometría Raman , Espectrometría Raman/métodos , Cinética , Pirenos/química , Pirenos/metabolismo , Biomimética , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/química , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Propiedades de Superficie , Activación Metabólica , Sistema Enzimático del Citocromo P-450/metabolismo , Oxidación-Reducción
8.
Bioresour Technol ; 403: 130857, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763203

RESUMEN

Immobilization technology is a promising way to improve effectiveness and stability of microbial remediation for polycyclic aromatic hydrocarbons (PAHs), in which carrier material is one of key factors restricting removal efficiency. In this study, fulvic acid-wheat straw biochar (FA/WS) composites were applied for immobilization of an efficient PAHs degrading bacterium Stenotrophomonas maltophilia (SPM). FA/WS&SPM showed superior degradation capacity than free bacteria and biochar-immobilized bacteria, with the removal efficiency of pyrene (20 mg L-1) reaching 90.5 % (7 days). Transcriptome analysis revealed that FA in the carrier materials can promote transportation and degradation of pyrene, and cell growth, as well as inhibit cell apoptosis. Enzyme activity and degradation products detection showed that SPM utilized both phthalic acid and salicylic acid metabolic pathways to degrade pyrene. Practicality of FA/WS&SPM for different kinds of PAHs remediation had been verified in contaminated soil, demonstrating a great potential in the field of PAHs polluted sites remediation.


Asunto(s)
Benzopiranos , Biodegradación Ambiental , Células Inmovilizadas , Pirenos , Stenotrophomonas maltophilia , Stenotrophomonas maltophilia/metabolismo , Pirenos/metabolismo , Benzopiranos/metabolismo , Células Inmovilizadas/metabolismo , Carbón Orgánico/química , Carbón Orgánico/farmacología
9.
J Hazard Mater ; 473: 134589, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38772114

RESUMEN

Epidemiological evidence indicates that exposure to halogenated polycyclic aromatic hydrocarbons (HPAHs) is associated with many adverse effects. However, the mechanisms of metabolic disorder of HPAHs remains limited. Herein, effects of pyrene (Pyr), and its halogenated derivatives (1-chloropyrene (1-Cl-Pyr), 1-bromopyrene (1-Br-Pyr)) on endogenous metabolic pathways were investigated, in human hepatoma (HepG2) and HepG2-derived cell lines expressing various human cytochrome P450s (CYPs). Non-targeted metabolomics results suggested that 1-Br-Pyr and Pyr exposure (625 nM) induced disruption in glutathione and riboflavin metabolism which associated with redox imbalance, through abnormal accumulation of oxidized glutathione, mediated by bioactivation of CYP2E1. Conversely, CYP2C9-mediated 1-Cl-Pyr significantly interfered with glutathione metabolism intermediates, including glycine, L-glutamic acid and pyroglutamic acid. Notably, CYP1A1-mediated Pyr-induced perturbation of amino acid metabolism which associated with nutrition and glycolipid metabolism, resulting in significant upregulation of most amino acids, whereas halogenated derivatives mediated by CYP1A2 substantially downregulated amino acids. In conclusion, this study suggested that Pyr and its halogenated derivatives exert potent effects on endogenous metabolism disruption under the action of various exogenous metabolic enzymes (CYPs). Thus, new evidence was provided to toxicological mechanisms of HPAHs, and reveals potential health risks of HPAHs in inducing diseases caused by redox and amino acid imbalances.


Asunto(s)
Aminoácidos , Sistema Enzimático del Citocromo P-450 , Glutatión , Humanos , Glutatión/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Aminoácidos/metabolismo , Células Hep G2 , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/metabolismo , Pirenos/metabolismo , Pirenos/toxicidad
10.
Chemosphere ; 360: 142384, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797205

RESUMEN

Interactions between polycyclic aromatic hydrocarbons (PAHs) and titanium dioxide (TiO2) nanoparticles (NPs) can produce unforeseen photoproducts in the aqueous phase. Both PAHs and TiO2-NPs are well-studied and highly persistent environmental pollutants, but the consequences of PAH-TiO2-NP interactions are rarely explored. We investigated PAH photoproduct formation over time for benzo[a]pyrene (BaP), fluoranthene (FLT), and pyrene (PYR) in the presence of ultraviolet A (UVA) using a combination of analytical and computational methods including, identification of PAH photoproducts, assessment of expression profiles for gene indicators of PAH metabolism, and computational evaluation of the reaction mechanisms through which certain photoproducts might be formed. Chemical analyses identified diverse photoproducts, but all PAHs shared a primary photoproduct, 9,10-phenanthraquinone (9,10-PQ), regardless of TiO2-NP presence. The computed reaction mechanisms revealed the roles photodissociation and singlet oxygen chemistry likely play in PAH mediated photochemical processes that result in the congruent production of 9,10-PQ within this study. Our investigation of PAH photoproduct formation has provided substantial evidence of the many, diverse and congruent, photoproducts formed from physicochemically distinct PAHs and how TiO2-NPs influence bioavailability and time-related formation of PAH photoproducts.


Asunto(s)
Nanopartículas , Procesos Fotoquímicos , Hidrocarburos Policíclicos Aromáticos , Titanio , Rayos Ultravioleta , Titanio/química , Hidrocarburos Policíclicos Aromáticos/química , Nanopartículas/química , Fluorenos/química , Pirenos/química , Benzo(a)pireno/química , Contaminantes Ambientales/química , Disponibilidad Biológica
11.
Carbohydr Polym ; 338: 122090, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38763704

RESUMEN

Size exclusion chromatography (SEC) and pyrene excimer formation (PEF) experiments were conducted to characterize the local density profile inside a glycogen sample before (Glycogen) and after (Gly-ß-LD) treatment with ß-amylase. These experiments were conducted to assess whether the density at the periphery of the glycogen particles was very high to limit access to proteins involved in the metabolism of glycogen as predicted by the Tier model or low as suggested by the Gilbert model. SEC analysis indicated that the density inside the Glycogen and Gly-ß-LD samples remained constant with particle size and was not affected by ß-amylolysis. Analysis of the PEF experiments conducted on the Glycogen and Gly-ß-LD samples labeled with 1-pyrenebutyric acid showed that the particles have a dense interior and loose corona. The conclusions reached by the SEC and PEF experiments agree with the Gilbert model and have implications for the association of glycogen ß-particles into larger α-particles.


Asunto(s)
Cromatografía en Gel , Glucógeno , Tamaño de la Partícula , Pirenos , Pirenos/química , Glucógeno/química , Cromatografía en Gel/métodos , beta-Amilasa/metabolismo , beta-Amilasa/química , Fluorescencia
12.
Chemistry ; 30(34): e202400322, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629212

RESUMEN

This study presents the synthesis and characterization of two fluorescent norbornadiene (NBD) photoswitches, each incorporating two conjugated pyrene units. Expanding on the limited repertoire of reported photoswitchable fluorescent NBDs, we explore their properties with a focus on applications in bioimaging of amyloid beta (Aß) plaques. While the fluorescence emission of the NBD decreases upon photoisomerization, aligning with what has been previously reported, for the first time we observed luminescence after irradiation of the quadricyclane (QC) isomer. We deduce how the observed emission is induced by photoisomerization to the excited state of the parent isomer (NBD) which is then the emitting species. Thorough characterizations including NMR, UV-Vis, fluorescence, X-ray structural analysis and density functional theory (DFT) calculations provide a comprehensive understanding of these systems. Notably, one NBD-QC system exhibits exceptional durability. Additionally, these molecules serve as effective fluorescent stains targeting Aß plaques in situ, with observed NBD/QC switching within the plaques. Molecular docking simulations explore NBD interactions with amyloid, unveiling novel binding modes. These insights mark a crucial advancement in the comprehension and design of future photochromic NBDs for bioimaging applications and beyond, emphasizing their potential in studying and addressing protein aggregates.


Asunto(s)
Péptidos beta-Amiloides , Colorantes Fluorescentes , Pirenos , Colorantes Fluorescentes/química , Pirenos/química , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Norbornanos/química , Placa Amiloide/química , Placa Amiloide/diagnóstico por imagen , Teoría Funcional de la Densidad , Isomerismo , Espectrometría de Fluorescencia
13.
ACS Appl Mater Interfaces ; 16(14): 17219-17231, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38561895

RESUMEN

Herein, we demonstrate the detection of glucose in a noninvasive and nonenzymatic manner by utilizing an extended gate field-effect transistor (EGFET) based on the organic molecule pyrene phosphonic acid (PyP4OH8) incorporated nickel metal-organic framework (NiOM-MOF). The prepared electrode responds selectively to glucose instead of sucrose, fructose, maltose, ascorbic acid, and uric acid in a 1× phosphate buffer saline solution. Also, utilizing the scanning Kelvin probe system, the sensing electrode's work function (Φ) is measured to validate the glucose-sensing mechanism. The sensitivity, detection range, response time, limit of detection, and limit of quantification of the electrode are determined to be 24.5 µA mM-1 cm-2, 20 µM to 10 mM, less than 5 s, 2.73 µM, and 8.27 µM, respectively. Most interestingly, the developed electrode follows the Michaelis-Menten kinetics, and the calculated rate constant (km) 0.07 mM indicates a higher affinity of NiOM-MOF toward glucose. The real-time analysis has revealed that the prepared electrode is sensitive to detect glucose in real human saliva, and it can be an alternative device for the noninvasive detection of glucose. Overall, the outcomes of the EGFET studies demonstrate that the prepared electrodes are well-suited for expeditious detection of glucose levels in saliva.


Asunto(s)
Diabetes Mellitus , Estructuras Metalorgánicas , Humanos , Glucosa/análisis , Electrodos , Pirenos
14.
Chemosphere ; 356: 141875, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38583532

RESUMEN

While passive sampling of ultra-low aqueous concentrations of hydrophobic organic compounds in environmental aqueous media has emerged as a promising analytical technique, there is a lack of good understanding of the fundamental diffusive processes. In this research, we used a fluorophore, pyrene, as a model compound to track diffusion in polymers through absorption and environmental media exchange processes. We directly tracked the penetration of pyrene into polyethylene (PE) and polyoxymethylene (POM) rods during absorption from water by sectioning the rod after different stages of absorption and observing the fluorescence signal through a microscope. Diffusion profiles of pyrene in polymers were simulated by numerical integration of Fickian diffusion. The results indicated that the uptake process in PE is governed by Fick's law and the absorption and desorption kinetics are similar in this polymer. However, the observed uptake profiles of pyrene in POM were non-Fickian and the release kinetics out of POM was slower compared to uptake into the polymer. We show that slower desorption from POM makes corrections for nonequilibrium using performance reference compounds (PRCs) problematic for deployments in water or sediment where there is significant advection. However, for static sediment deployments, the overall kinetics of exchange is controlled by slow transport through sediment and the hysteretic behavior of POM may not preclude the use of PRCs to interpret equilibrium status.


Asunto(s)
Monitoreo del Ambiente , Polietileno , Pirenos , Resinas Sintéticas , Contaminantes Químicos del Agua , Pirenos/química , Polietileno/química , Difusión , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Monitoreo del Ambiente/métodos , Cinética , Polímeros/química
15.
J Colloid Interface Sci ; 665: 934-943, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38569310

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are excellent alternative luminophores for electrochemiluminescence (ECL) immunoassays. However, they are inevitably limited by the aggregation-caused quenching effect. In this study, aimed at eliminating the aggregation quenching of PAHs, luminescent metal-organic frameworks (MOFs) with 1,3,6,8-tetra(4-carboxybenzene)pyrene (H4TBAPy) as the ligand were exploited as a novel nano-emitter for the construction of ECL immunoassays. The luminophore exhibits efficient aggregation-induced emission enhancement, good acid-base resistance property and unusual ECL reactivity. In addition, the simultaneous use of potassium persulfate and hydrogen peroxide as dual co-reactants resulted in a synergistic enhancement of the cathodic ECL efficiency. The use of magnetic iron-nickel alloys as the multifunctional sensing platform can further enhance the ECL activity, and its enriched zero-valent iron as a co-reactant accelerator effectively drives ECL analytical performance. Profiting from the excellent characteristics, signal-on ECL immunoassays have been constructed. With carcinoembryonic antigen as the model analysis target, a detection limit of 0.63 pg/mL was obtained within the linear range of 1 pg/mL to 50 ng/mL, accompanied by excellent analytical performance. This report opens a new window for the rational design of efficient ECL illuminators, and the proposed ECL immunoassays may find promising applications in the detection of disease markers.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Estructuras Metalorgánicas , Hidrocarburos Policíclicos Aromáticos , Pirenos , Inmunoensayo , Hierro , Mediciones Luminiscentes , Técnicas Electroquímicas , Límite de Detección
16.
Chemosphere ; 356: 141886, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582159

RESUMEN

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the air inside residential houses in Iran along with measuring the amount of 1-OHpyrene metabolite in the urine of the participants in the study was investigated by gas chromatography-mass spectrometry (GC-MS). Demographic characteristics (including age, gender, and body composition), equipment affecting air quality, and wealth index were also investigated. The mean ± standard error (SE) concentration of particulate matter 10 (PM10) and ∑PAHs in the indoor environment was 43.2 ± 1.98 and 1.26 ± 0.15 µg/m3, respectively. The highest concentration of PAHs in the indoor environment in the gaseous and particulate phase related to Naphthalene was 1.1 ± 0.16 µg/m3 and the lowest was 0.01 ± 0. 0.001 µg/m3 Pyrene, while the most frequent compounds in the gas and particle phase were related to low molecular weight hydrocarbons. 30% of the samples in the indoor environment have BaP levels higher than the standards provided by WHO guidelines. 68% of low molecular weight hydrocarbons were in the gas phase and 73 and 75% of medium and high molecular weight hydrocarbons were in the particle phase. There was a significant relationship between the concentration of some PAH compounds with windows, evaporative coolers, printers, and copiers (p < 0.05). The concentration of PAHs in houses with low economic status was higher than in houses with higher economic status. The average concentration of 1-hydroxypyrene metabolite in the urine of people was 7.10 ± 0.76 µg/L, the concentration of this metabolite was higher in men than in women, and there was a direct relationship between the amount of this metabolite in urine and the amount of some hydrocarbon compounds in the air, PM10, visceral fat and body fat. This relationship was significant for age (p = 0.01). The concentration of hydrocarbons in the indoor environment has been above the standard in a significant number of non-smoking indoor environments, and the risk assessment of these compounds can be significant. Also, various factors have influenced the amount of these compounds in the indoor air, and paying attention to them can be effective in reducing these hydrocarbons in the air.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Monitoreo Biológico , Material Particulado , Hidrocarburos Policíclicos Aromáticos , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/orina , Humanos , Irán , Masculino , Femenino , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/orina , Adulto , Material Particulado/análisis , Persona de Mediana Edad , Monitoreo del Ambiente , Pirenos/análisis , Pirenos/orina , Exposición a Riesgos Ambientales/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Adulto Joven , Vivienda , Cromatografía de Gases y Espectrometría de Masas
17.
World J Surg ; 48(4): 978-988, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38502051

RESUMEN

BACKGROUND: Inferior vena cava (IVC) resection is essential for complete (R0) excision of some malignancies. However, the optimal material for IVC reconstruction remains unclear. Our objective is to demonstrate the efficacy, safety, and advantages of using Non-Fascial Autologous Peritoneum (NFAP) for IVC reconstruction. To conduct a literature review of surgical strategies for tumors involving the IVC. METHODS: We reviewed all IVC reconstructions performed at our institution between 2015 and 2023. Preoperative, operative, postoperative, and follow-up data were collected and analyzed. RESULTS: A total of 33 consecutive IVC reconstructions were identified: seven direct sutures, eight venous homografts (VH), and 18 NFAP. With regard to NFAP, eight tubular (mean length, 12.5 cm) and 10 patch (mean length, 7.9 cm) IVC reconstructions were performed. Resection was R0 in 89% of the cases. Two patients had Clavien-Dindo grade I complications, 2 grade II, 2 grade III and 2 grade V complications. The only graft-related complication was a case of early partial thrombosis, which was conservatively treated. At a mean follow-up of 25.9 months, graft patency was 100%. There were seven recurrences and six deaths. Mean overall survival (OS) was 23.4 months and mean disease-free survival (DFS) was 14.4 months. According to our results, no statistically significant differences were found between NFAP and VH. CONCLUSIONS: NFAP is a safe and effective alternative for partial or complete IVC reconstruction and has many advantages over other techniques, including its lack of cost, wide and ready availability, extreme handiness, and versatility. Further comparative studies are required to determine the optimal technique for IVC reconstruction.


Asunto(s)
Peritoneo , Pirenos , Vena Cava Inferior , Humanos , Vena Cava Inferior/cirugía , Vena Cava Inferior/patología , Peritoneo/cirugía , Estudios Retrospectivos , Venas , Resultado del Tratamiento
18.
Macromol Rapid Commun ; 45(11): e2400029, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38477018

RESUMEN

Organic and polymer fluorescent nanomaterials are a frontier research focus. Here in this work, a series of fluorinated zwitterionic random copolymers end-attached with a quasi-chromophoric group of pyrene or tetraphenylethylene (TPE) are well synthesized via atom transfer radical polymerization with activators regenerated by electron transfer (ARGET ATRP). Those random copolymers with total degree of polymerization 100 or 200 are able to produce fluorescent single-chain nanoparticles (SCNPs) through intra-chain self-folding assembly with quite uniform diameters in the range of 10-20 nm as characterized by dynamic light scattering and transmission electron microscopy. By virtue of the segregation or confinement effect, both SCNPs functionalized with pyrene or TPE group are capable of emitting fluorescence, with pyrene tethered SCNPs exhibiting stronger fluorescence emission reaching the highest quantum yield ≈20%. Moreover, such kind of fluorescent SCNPs manifest low cytotoxicity and good cell imaging performance for Hela cells. The creation of fluorescent SCNPs through covalently attached one quasi-chromophore to the end of one fluorinated zwitterionic random copolymer provides an alternative strategy for preparing polymeric luminescence nanomaterials, promisingly serving as a new type of fluorescent nanoprobes for biological imaging applications.


Asunto(s)
Colorantes Fluorescentes , Nanopartículas , Imagen Óptica , Polímeros , Humanos , Células HeLa , Nanopartículas/química , Polímeros/química , Colorantes Fluorescentes/química , Estilbenos/química , Estructura Molecular , Fluorescencia , Halogenación , Pirenos/química , Tamaño de la Partícula , Supervivencia Celular/efectos de los fármacos , Polimerizacion
19.
Adv Healthc Mater ; 13(17): e2303782, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38430208

RESUMEN

Exosomes are small extracellular vesicles that play a crucial role in intercellular communication and offer significant potential for a wide range of biomedical applications. However, conventional methods for exosome isolation have limitations in terms of purity, scalability, and preservation of exosome structural integrity. To address these challenges, an exosome isolation platform using chitosan oligosaccharide lactate conjugated 1-pyrenecarboxylic acid (COL-Py) based self-assembled magnetic nanoclusters (CMNCs), is presented. CMNCs are characterized to optimize their size, stability, and interaction dynamics with exosomes. The efficiency of CMNCs in isolating exosomes is systematically evaluated using various analytical methods to demonstrate their ability to capture exosomes based on amphiphilic lipid bilayers. CMNC-based exosome isolation consistently yields exosomes with structural integrity and purity similar to those obtained using traditional methods. The reusability of CMNCs over multiple exosome isolation cycles underscores their scalability and offers an efficient solution for biomedical applications. These results are supported by western blot analysis, which demonstrated the superiority of CMNC-based isolation in terms of purity compared to conventional methods. By providing a scalable and efficient exosome isolation process that preserves both structural integrity and purity, CMNCs can constitute a new platform that can contribute to the field of exosome studies.


Asunto(s)
Quitosano , Exosomas , Quitosano/química , Exosomas/química , Exosomas/metabolismo , Humanos , Oligosacáridos/química , Pirenos/química , Nanopartículas de Magnetita/química , Ácido Láctico/química , Ácidos Carboxílicos/química
20.
Bioresour Technol ; 399: 130633, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552862

RESUMEN

The remediation for polycyclic aromatic hydrocarbons contaminated soil with cost-effective method has received significant public concern, a composite material, therefore, been fabricated by loading humic acid into biochar in this study to activate persulfate for naphthalene, pyrene and benzo(a)pyrene remediation. Experimental results proved the hypothesis that biochar loaded humic acid combined both advantages of individual materials in polycyclic aromatic hydrocarbons adsorption and persulfate activation, achieved synergistic performance in naphthalene, pyrene and benzo(a)pyrene removal from aqueous solution with efficiency reached at 98.2%, 99.3% and 90.1%, respectively. In addition, degradation played a crucial role in polycyclic aromatic hydrocarbons remediation, converting polycyclic aromatic hydrocarbons into less toxic intermediates through radicals of ·SO4-, ·OH, ·O2-, and 1O2 generated from persulfate activation process. Despite pH fluctuation and interfering ions inhibited remediation efficiency in some extent, the excellent performances of composite material in two field soil samples (76.7% and 91.9%) highlighted its potential in large-scale remediation.


Asunto(s)
Carbón Orgánico , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Sustancias Húmicas , Suelo , Benzo(a)pireno , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Pirenos , Naftalenos
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