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1.
Environ Monit Assess ; 192(8): 494, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32642872

RESUMO

Agitation-assisted dispersive liquid-liquid extraction without a dispersing solvent is lately receiving considerable attention owing to the low to no solvent loss relative to its predecessor, which suffers severe extracting solvent loss. Herein, we report the application of a simple agitation-assisted dispersive liquid-liquid microextraction method, without a disperser solvent, for the extraction of naphthalene and its derivatives from aqueous solutions. Under the optimised conditions, namely, 25 µL 3:1 mixture of dichloroethane and ethylacetate with 20 s agitation, in 2-mL aqueous solutions containing 10% NaCl, the method demonstrated acceptable figures of merit: linearity-R2 ≥ 0.9914 in the concentration range 0.5-50 ng/mL, repeatability (%RSD ≤ 12.9 for n = 15) and limits of detection (0.034-0.081 ng/mL). The recoveries obtained from the spiked dam water sample were also satisfactory (94-103%). These parameters are comparable with those reported in literature, especially for dispersive liquid-liquid microextraction techniques albeit for different analytes. Despite only naphthol being detected in one of the three sampled sites, the method shows considerable promise for routine monitoring of river and dam water quality subject to accuracy validation using certified reference materials.


Assuntos
Microextração em Fase Líquida , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Limite de Detecção , Naftalenos , Solventes
2.
Sci Total Environ ; 736: 139567, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32479957

RESUMO

Naphthalene, a naturally-occurring polyaromatic hydrocarbon, pose potential threats to health for its wide exposures in environment. Naphthalene could disrupt the redox equilibrium resulting in oxidative damage. Antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) are considered to be the efficient defense barriers to protect organisms from negative impacts of toxicants. Limited information is available regarding the underlying molecular mechanism between antioxidant enzymes and naphthalene. In this paper, structural and functional alterations of CAT and SOD for low dose (1.6-25.6 mg/L) naphthalene exposure have been investigated at the molecular and cellular levels. The enzyme activity responses of CAT and SOD in hepatocytes for naphthalene were consistent with the molecular, in which the activity of CAT increased and the activity of SOD slightly inhibited. Spectroscopy methods and molecular docking were carried out to investigate the underlying binding mechanisms. Naphthalene exposure significantly changed the conformation of CAT with secondary structure alteration (α-helix increase) but only changed the skeleton structure of SOD without secondary structure alteration. Naphthalene could bind to CAT and SOD primarily via H-binding force accompanied with the particle size of CAT/SOD agglomerates decreasing. Naphthalene preferentially bound to the surface of CAT and SOD. Besides, naphthalene could also bind directly to the active center of CAT with the key residues Arg364 and Tyr 357 for activity. This paper provides a combined cellular and molecular strategy to research biomarker responses for toxicants exposure. Besides, this study offers detailed basic data for the comprehensive understanding of naphthalene toxicity.


Assuntos
Antioxidantes , Superóxido Dismutase , Catalase , Simulação de Acoplamento Molecular , Naftalenos , Estresse Oxidativo
3.
Chemosphere ; 255: 126958, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388262

RESUMO

Secondary nonferrous metal smelters are important sources of unintentionally produced persistent organic pollutants (UPOPs) including polychlorinated biphenyls (PCBs), polychlorinated naphthalenes, pentachlorobenzene, and hexachlorobenzene. Quantifying UPOP emissions by the main sources is an important step when evaluating UPOP emissions and establishing an inventory. In this study, field investigations were performed to allow UPOP emissions and distributions in stack gases emitted by secondary nonferrous metal smelters to be compared. A total of 25 stack gas samples were collected from secondary copper smelters (SCus), secondary zinc smelters, and secondary lead smelters in China. The mean toxic equivalent concentrations (TEQs) and mass concentrations of most of the UPOPs were highest in the secondary zinc smelter stack gas samples, next highest in the SCu stack gas samples, and lowest in the secondary lead smelter stack gas samples. The mean dioxin-like PCB and polychlorinated naphthalene TEQs were ∼8.9 and ∼6.6 times higher in stack gases from a SCu equipped with an oxygen-enriched smelting furnace than in stack gases from a SCu with a converter furnace. The mean PCB-118 to PCB-123 ratios and CN-10 to CN-35 ratios varied strongly and could be used as diagnostic ratios for apportioning the sources of UPOPs in the environment. Emission factors for dioxin-like PCBs, polychlorinated naphthalenes, pentachlorobenzene, and hexachlorobenzene in stack gases from secondary nonferrous metal smelters were derived and updated. The results improve our understanding of UPOP emission and provide data for establishing UPOP emission inventories for secondary nonferrous metal smelters.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metalurgia , Clorobenzenos , Cobre , Dioxinas/análise , Gases/análise , Hexaclorobenzeno , Naftalenos , Bifenilos Policlorados , Dibenzodioxinas Policloradas/análise
4.
Chemosphere ; 255: 126955, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32416390

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) can induce skin toxicity. Although some investigations have been conducted to assess the skin toxicity of different PAHs, few comparisons using a series of PAHs with different ring numbers and arrangements have been done. We aimed to explore the skin absorption of 6 PAH compounds and their effect on cutaneous inflammation. In vitro skin permeation was rated by Franz cell with pig skin. Molecular docking was employed to compute the PAH interaction with stratum corneum (SC) lipids. Cultured keratinocytes were exposed to PAHs for analyzing cytotoxicity, cyclooxygenase (COX)-2, prostaglandin E2 (PGE2), chemokines, and differentiation proteins. The in vivo topical PAH exposure in mice was characterized by skin absorption, transepidermal water loss (TEWL), PGE2 level, and histology. The skin deposition from the aqueous vehicle increased following the increase of PAH lipophilicity and molecular size, with benzo[a]pyrene (5-ring PAH) showing the greatest absorption. Pyrene was the compound showing the highest penetration across the skin (flux). Although the PAHs fluoranthene, pyrene, chrysene, and 1,2-benzanthracene all had 4 rings, the skin permeation was quite different. 1,2-Benzanthracene showed the greatest absorption among the 4-ring compounds. The PAHs with higher absorption exhibited stronger interaction with SC lipids according to the in silico modeling. Chrysene and 1,2-benzanthracene generally showed the highest COX-2 and PGE2 expression, followed by benzo[a]pyrene. The lowest COX-2 and PGE2 upregulation was observed for naphthalene (2-ring PAH). A contrary tendency was detected for the upregulation of chemokines. Filaggrin and integrin ß1 in keratinocytes were suppressed at a comparable level by all PAHs. The skin's absorption of PAHs showed strong in vivo-in vitro correlation. 1,2-Benzanthracene and benzo[a]pyrene highly disrupted the skin barrier and elevated the inflammation in vivo. The tendency toward in vivo inflammation caused by various PAHs could be well predicted by the combined estimation using in vitro skin absorption and a keratinocyte bioassay. This study also established the structure-permeation relationship (SPR) of PAHs.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Absorção Cutânea , Pele/metabolismo , Animais , Benzo(a)Antracenos , Benzo(a)pireno/toxicidade , Crisenos , Inflamação/metabolismo , Queratinócitos , Camundongos , Simulação de Acoplamento Molecular , Naftalenos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Pirenos , Suínos
5.
Artigo em Inglês | MEDLINE | ID: mdl-32400278

RESUMO

Degradation studies of phenanthrene and naphthalene as a mixture was carried out using a developed bacterial consortium. The isolates used in consortium were identified as Chryseobacterium sp., Sphingobacterium sp., Stenotrophomonas sp., Agromyces sp. and Pseudomonas sp. Limited work is done on genus Agromyces in degradation studies of PAHs. Catechol production was detected using Arnow's assay suggested that the pathway used for degradation is the meta-cleavage pathway. Results showed that Tween 80, as a surfactant, had maximum effect on the growth of isolates during PAH degradation. This suggests that use of Tween 80 as a surfactant enhanced the uptake of PAH by bacterial isolates during degradation. The study further revealed that, bacterial consortium was successfully utilized in the treatment of water contaminated with PAH in a laboratory-scale biofilm bioreactor. The bacterial consortium was able to degrade 99.9% of naphthalene and 92.9% of phenanthrene as a mixture at a high concentration of 2000 mg/L within 6 days. Further scaling up of the biofilm bioreactor can prove beneficial in large scale treatment of PAH contaminated water. This study showed promising results and these bacterial strains can be used as potential tools for bioremediation of PAH in contaminated sites.


Assuntos
Microbiota , Naftalenos/metabolismo , Fenantrenos/metabolismo , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Catecóis/análise , Testes de Sensibilidade Microbiana , Microbiota/efeitos dos fármacos , Modelos Teóricos , Pseudomonas/isolamento & purificação , Pseudomonas/metabolismo , Sphingobacterium/isolamento & purificação , Sphingobacterium/metabolismo
6.
Chemosphere ; 256: 126928, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32442796

RESUMO

Phenols and trans-1,2-dihydro-1,2-diols are metabolites commonly formed in vivo in fish upon exposure to polycyclic aromatic hydrocarbons (PAHs). These metabolites are excreted via the bile and gas chromatography-mass spectrometry (GC-MS) analysis of bile is becoming more frequently used for evaluating PAH exposure levels in fish. Current protocols focus on the detection and quantification of phenols formed during in vivo oxidation of PAHs, leaving out analyses and quantification of other oxidation products such as trans-1,2-dihydro-1,2-diols, potentially underestimating exposure levels. Herein, four trans-1,2-dihydro-1,2-diols, namely trans-1,2-dihydronaphthalene-1,2-diol, trans-6-methyl-1,2-dihydronaphthalene-1,2-diol, trans-5,7-dimethyl-1,2-dihydronaphthalene-1,2-diol, and trans-4,6,7-trimethyl-1,2-dihydronaphthalene-1,2-diol, were successfully prepared and used as standards in the GC-MS analysis, aiming to further develop this qualitative and quantitative analytical method for the determination of PAH exposures. This study shows that the currently used GC-MS analysis, including sample workup, is not suitable for determining the quantity of the corresponding diols derived from naphthalene and methylated naphthalenes. Alternative approaches are needed to provide a correct estimate of PAH exposure levels.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Bile/metabolismo , Peixes , Gadus morhua/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Naftalenos
7.
Ecotoxicol Environ Saf ; 200: 110747, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460052

RESUMO

The presence of surfactants may affect the bioavailability of polycyclic aromatic hydrocarbons. A hydroponic experiment was conducted to investigate the response of Hydrocharis dubia (Bl.) Backer to different concentrations of linear alkylbenzene sulfonate (LAS), naphthalene (NAP) and their mixture (0.5, 5, 10, and 20 mg/L) for 14 days and 28 days. The results showed that LAS had a greater toxic effect on H. dubia growth than NAP at treatment concentrations of 0.5-20 mg/L. The combined effect of LAS and NAP was damaging to H. dubia at concentrations of LAS + NAP ≥5 + 5 mg/L. When LAS + NAP ≥10 + 10 mg/L, the underground parts of H. dubia suffered more significant damage than the aboveground parts. Under the treatments with LAS, NAP and their mixture, H. dubia experienced oxidative stress. Soluble proteins and antioxidant enzymes were the main substances protecting H. dubia from LAS stress, and superoxide dismutase (SOD) and peroxidase (POD) were the main protective enzymes. When exposed to NAP, H. dubia growth was stimulated and promoted at the same time. In the short-term treatment (14 d), catalase (CAT) activity was sensitive to NAP stimulation, and soluble proteins and SOD were the main protective substances produced. Soluble sugars, SOD and ascorbate peroxidase (APX) played important protective roles during the longer exposure time (28 d). The physiological response of H. dubia exposed to the combined toxicants was weaker than the response to exposure to individual toxicants. The responses of SOD and CAT activity were positive in the short term (14 d), and these were the main protective enzymes. As the exposure time increased (28 d), the plant antioxidant system responded negatively.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Hydrocharitaceae/efeitos dos fármacos , Naftalenos/toxicidade , Tensoativos/toxicidade , Ácidos Alcanossulfônicos/antagonistas & inibidores , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Sinergismo Farmacológico , Hydrocharitaceae/enzimologia , Hydrocharitaceae/metabolismo , Naftalenos/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Superóxido Dismutase/metabolismo
8.
Aquat Toxicol ; 224: 105480, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32417752

RESUMO

The calanoid copepod, Acartia tonsa, is relatively sensitive to marine pollution. Glutathione S-transferase (GST) multifunctional enzyme, as a biomarker, play an important role in detoxification metabolism of exogenous substances. In the present study, GST-theta and GST-mu class homology genes (designated as AtGSTT1 and AtGSTM2) were identified and characterized from A. tonsa. The coding sequence of AtGSTT1 comprised 726 bp and encoded a putative protein of 241 amino acid residues. AtGSTM2 contained an open reading frame of 678 bp that encoded a putative 227 amino acid polypeptide. Both proteins contained a conserved GST-N domain and a GST-C domain. Structural analysis revealed the characteristic N-terminal G-site. Three-dimensional structure analysis showed that AtGSTT1 and AtGSTM2 have two typical domains of GST family: The ßαßαßßα topology structure at the N- terminus and the superhelical structure at the C- terminus. Subsequently, the expression levels of the two GST genes were detected in A. tonsa using real-time quantitative PCR after exposure to 1,2-dimethylnaphthalene (C2-NAPH) at different concentrations (0.574, 5.736 and 57.358 µg/L) for 24, 48, 72, and 96 h. AtGSTT1 mRNA expression was significantly up-regulated in a time-dependent manner and the highest mRNA expression occurred at 5.736 µg/L C2-NAPH exposure for 96 h. AtGSTM2 mRNA expression peaked at 72 h in 0.574 µg/L and 5.736 µg/L dose groups. The expression level of AtGSTM2 showed an increasing trend in a time-dependent manner at 57.358 µg/L of C2-NAPH. These results suggested that GST genes may play an important role in protecting A. tonsa from C2-NAPH pollution, and provide a theoretical basis for further study on the molecular mechanism of polycyclic aromatic hydrocarbon (PAHs) pollution on zooplankton.


Assuntos
Copépodes/efeitos dos fármacos , Monitoramento Ambiental/métodos , Glutationa Transferase/genética , Naftalenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Sequência de Bases , Clonagem Molecular , Copépodes/enzimologia , Copépodes/genética , DNA Complementar/genética , Relação Dose-Resposta a Droga , Glutationa Transferase/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , RNA Mensageiro/genética , Testes de Toxicidade Aguda
9.
Environ Sci Technol ; 54(9): 5409-5418, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32259434

RESUMO

Naphthalene (NAP), as a surrogate of intermediate-volatility organic compounds (IVOCs), has been proposed to be an important precursor of secondary organic aerosol (SOA). However, the relative contribution of its emission sources is still not explicit. This study firstly conducted the source apportionment of atmospheric NAP using a triple-isotope (δ13C, δ2H, and Δ14C) technique combined with a Bayesian model in the Beijing-Tianjin-Hebei (BTH) region of China. At the urban sites, stable carbon (-27.7 ± 0.7‰, δ13C) and radiocarbon (-944.0 ± 20.4‰, Δ14C) isotope compositions of NAP did not exhibit significant seasonal variation, but the deuterium system showed a relatively more 2H depleted signature in winter (-86.7 ± 8.9‰, δ2H) in comparison to that in summer (-56.4 ± 3.9‰, δ2H). Radiocarbon signatures indicated that 95.1 ± 1.8% of NAP was emitted from fossil sources in these cities. The Bayesian model results indicated that the emission source compositions in the BTH urban sites had a similar pattern. The contribution of liquid fossil combustion was highest (46.7 ± 2.6%), followed by coal high-temperature combustion (26.8 ± 7.1%), coal low-temperature combustion (18.9 ± 6.4%), and biomass burning (7.6 ± 3.1%). At the suburban site, the contribution of coal low-temperature combustion could reach 70.1 ± 6.4%. The triple-isotope based approach provides a top-down constraint on the sources of atmospheric NAP and could be further applied to other IVOCs in the ambient atmosphere.


Assuntos
Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis , Teorema de Bayes , Pequim , China , Cidades , Monitoramento Ambiental , Isótopos , Naftalenos , Volatilização
10.
Environ Pollut ; 263(Pt A): 114454, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32247922

RESUMO

Natural aeolian dust (AD) particles are potential carriers of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere. The heterogeneous interaction between them may lead to worsened air quality and enhanced cytotoxicity and carcinogenicity of ambient particulates in downwind areas, and this topic requires in-depth exploration. In this study, AD samples were collected from four Asian dust sources, and their physical properties and compositions were determined, showing great regional differences. The physical and chemical interactions of different AD particles with naphthalene (Nap; model PAH) were observed in aqueous systems. The results showed that AD particles from the Loess Plateau had weak adsorption to Nap, which was fitted by the Langmuir isotherm. There was no obvious adsorption to Nap found for the other three AD samples. This difference seemed to depend mainly on the specific surface area and/or the total pore volume. In addition, the Nap in the aqueous solution did not undergo chemical reactions under dark conditions and longwave ultraviolet (UV) radiation but degraded under shortwave UV radiation, and 2-formylcinnamaldehyde and 1,4-naphthoquinone were the first-generated products. The degradation of Nap in the aqueous solution was probably initiated by photoionization, and the reaction rate constant (between 1.44 × 10-4 min-1 and 8.55 × 10-4 min-1) was much lower than that of Nap with hydroxyl radicals. Instead of inducing or promoting the chemical change in Nap, the AD particles slowed photodegradation due to the extinction of radiation. Therefore, it is inferred that natural AD particles have no substantial effect on the transportation and transformation of PAHs in the atmosphere.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Atmosfera , Carvão Mineral/análise , Poeira/análise , Naftalenos
11.
Proc Natl Acad Sci U S A ; 117(18): 9991-10002, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32312805

RESUMO

The initial response to an addictive substance can facilitate repeated use: That is, individuals experiencing more positive effects are more likely to use that drug again. Increasing evidence suggests that psychoactive cannabinoid use in adolescence enhances the behavioral effects of cocaine. However, despite the behavioral data, there is no neurobiological evidence demonstrating that cannabinoids can also alter the brain's initial molecular and epigenetic response to cocaine. Here, we utilized a multiomics approach (epigenomics, transcriptomics, proteomics, and phosphoproteomics) to characterize how the rat brain responds to its first encounter with cocaine, with or without preexposure to the synthetic cannabinoid WIN 55,212-2 (WIN). We find that in adolescent (but not in adult) rats, preexposure to WIN results in cross-sensitization to cocaine, which correlates with histone hyperacetylation and decreased levels of HDAC6 in the prefrontal cortex (PFC). In the PFC, we also find that WIN preexposure blunts the typical mRNA response to cocaine and instead results in alternative splicing and chromatin accessibility events, involving genes such as Npas2 Moreover, preexposure to WIN enhances the effects of cocaine on protein phosphorylation, including ERK/MAPK-targets like gephyrin, and modulates the synaptic AMPAR/GluR composition both in the PFC and the nucleus accumbens (NAcc). PFC-NAcc gene network topological analyses, following cocaine exposure, reveal distinct top nodes in the WIN preexposed group, which include PACAP/ADCYAP1. These preclinical data demonstrate that adolescent cannabinoid exposure reprograms the initial behavioral, molecular, and epigenetic response to cocaine.


Assuntos
Comportamento Aditivo/genética , Comportamento Animal/efeitos dos fármacos , Canabinoides/efeitos adversos , Cocaína/efeitos adversos , Adolescente , Animais , Comportamento Aditivo/induzido quimicamente , Comportamento Aditivo/patologia , Benzoxazinas/efeitos adversos , Benzoxazinas/farmacologia , Canabinoides/farmacologia , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Cocaína/farmacologia , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Desacetilase 6 de Histona/genética , Humanos , Proteínas de Membrana/farmacologia , Morfolinas/efeitos adversos , Morfolinas/farmacologia , Naftalenos/efeitos adversos , Naftalenos/farmacologia , Fosfoproteínas/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Córtex Pré-Frontal/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Ratos , Transcriptoma/efeitos dos fármacos
12.
PLoS One ; 15(4): e0232428, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343734

RESUMO

BACKGROUND: Elevated parathyroid hormone (PTH) levels in secondary hyperparathyroidism (SHPT) lead to vascular calcification, which is associated with cardiovascular events and mortality. Increased PTH production is caused by the excessive proliferation of parathyroid gland cells, which is accelerated by abnormal mineral homeostasis. Evocalcet, an oral calcimimetic agent, inhibits the secretion of PTH from parathyroid gland cells and has been used for the management of SHPT in dialysis patients. We observed the effects of evocalcet on ectopic calcification and parathyroid hyperplasia using chronic kidney disease (CKD) rats with SHPT. METHODS: CKD rats with SHPT induced by adenine received evocalcet orally for 5 weeks. The calcium and inorganic phosphorus content in the aorta, heart and kidney was measured. Ectopic calcified tissues were also assessed histologically. To observe the effects on the proliferation of parathyroid gland cells, parathyroid glands were histologically assessed in CKD rats with SHPT induced by 5/6 nephrectomy (Nx) after receiving evocalcet orally for 4 weeks. RESULTS: Evocalcet prevented the increase in calcium and inorganic phosphorus content in the ectopic tissues and suppressed calcification of the aorta, heart and kidney in CKD rats with SHPT by reducing the serum PTH and calcium levels. Evocalcet suppressed the parathyroid gland cell proliferation and reduced the sizes of parathyroid cells in CKD rats with SHPT. CONCLUSIONS: These findings suggest that evocalcet would prevent ectopic calcification and suppress parathyroid hyperplasia in patients with SHPT.


Assuntos
Hiperparatireoidismo Secundário/complicações , Naftalenos/uso terapêutico , Glândulas Paratireoides/patologia , Pirrolidinas/uso terapêutico , Calcificação Vascular/prevenção & controle , Animais , Calcimiméticos/uso terapêutico , Hiperplasia/etiologia , Hiperplasia/prevenção & controle , Masculino , Ratos , Ratos Sprague-Dawley , Calcificação Vascular/etiologia
13.
Ecotoxicol Environ Saf ; 196: 110533, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247241

RESUMO

1-naphthol (1-NAP) is the main metabolite of pesticide carbaryl and naphthalene, and is also a genotoxic and carcinogenic intermediate in the synthesis of organic compound, dyes, pigment and pharmaceutical industry. In this work, two novel haptens were designed and synthesized for developing a competitive indirect enzyme-linked immunosorbent assay (ciELISA) method for 1-NAP in urine samples. The assay showed a limit of detection of 2.21 ng/mL and working range from 4.02 ng/mL to 31.25 ng/mL for 1-NAP in optimized working buffer. The matrix effect of samples was eliminated via 15-fold dilution of optimized working buffer. Good average recoveries (102.4%-123.4%) with a coefficient of variation from 11.7% to 14.7% was obtained for spiked urine samples. Subsequent instrument verification test showed good correlation between the results of ciELISA and high-performance liquid chromatography. The developed ciELISA is a high-throughput tool to monitor 1-NAP in urine, which can provide technical support for the establishment of biological exposure level for the exposure to carbaryl, naphthalene and other related pollutants.


Assuntos
Anticorpos Monoclonais/química , Ensaio de Imunoadsorção Enzimática/métodos , Haptenos/química , Naftóis/urina , Resíduos de Praguicidas/urina , Anticorpos Monoclonais/imunologia , Carbaril/metabolismo , Exposição Ambiental/análise , Limite de Detecção , Naftalenos/metabolismo , Naftóis/imunologia , Resíduos de Praguicidas/imunologia , Resíduos de Praguicidas/metabolismo
14.
Nat Commun ; 11(1): 1830, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286350

RESUMO

A synthetic biology method based on heterologous biosynthesis coupled with genome mining is a promising approach for increasing the opportunities to rationally access natural product with novel structures and biological activities through total biosynthesis and combinatorial biosynthesis. Here, we demonstrate the advantage of the synthetic biology method to explore biological activity-related chemical space through the comprehensive heterologous biosynthesis of fungal decalin-containing diterpenoid pyrones (DDPs). Genome mining reveals putative DDP biosynthetic gene clusters distributed in five fungal genera. In addition, we design extended DDP pathways by combinatorial biosynthesis. In total, ten DDP pathways, including five native pathways, four extended pathways and one shunt pathway, are heterologously reconstituted in a genetically tractable heterologous host, Aspergillus oryzae, resulting in the production of 22 DDPs, including 15 new analogues. We also demonstrate the advantage of expanding the diversity of DDPs to probe various bioactive molecules through a wide range of biological evaluations.


Assuntos
Diterpenos/farmacologia , Fungos/química , Naftalenos/farmacologia , Pironas/farmacologia , Biologia Sintética , Peptídeos beta-Amiloides/metabolismo , Animais , Fármacos Anti-HIV/farmacologia , Aspergillus/química , Vias Biossintéticas/efeitos dos fármacos , Vias Biossintéticas/genética , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Drosophila/efeitos dos fármacos , Fungos/genética , Genoma Fúngico , HIV-1/efeitos dos fármacos , Humanos , Células MCF-7 , Naftalenos/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Agregados Proteicos , Pironas/química , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Estereoisomerismo
15.
Environ Pollut ; 262: 114267, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32179224

RESUMO

Multiple types of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and hexachlorobenzene (HCB), can be unintentionally released from combustion or thermal industrial processes, which are speculated to be the main sources of these contaminants, as they were banned on production and use since several decades ago. In this study, concentrations and sources of 40 PCBs, 39 PCNs, and HCB were analyzed in air samples collected during the period 2012-2015 at a background site in east China. ΣPCBs, ΣPCNs, and HCB were in the range of 9-341 pg/m3, 6-143 pg/m3, and 14-522 pg/m3, respectively. Seasonal characteristics with high levels in winter and low levels in summer were observed for PCNs and HCB. PCBs also exhibited slightly higher levels in winter. Source apportionment was conducted, using polycyclic aromatic hydrocarbons (PAHs) as combustion sources indicator, combined with principal component analysis (PCA) and positive matrix factorization (PMF) model. The results indicated that the legacy of past produced and used commercial PCBs was the dominant contributor (∼56%) to the selected PCBs in the atmosphere in east China. PCNs were mainly emitted from combustion sources (∼64%), whereas HCB almost entirely originated from combustion process (>90%).


Assuntos
Poluentes Atmosféricos/análise , Bifenilos Policlorados/análise , Atmosfera , China , Monitoramento Ambiental , Hexaclorobenzeno , Naftalenos/análise
16.
Environ Sci Pollut Res Int ; 27(15): 18717-18728, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32207019

RESUMO

The important role of oxygen-containing groups of porous carbonaceous materials (PCMs) on sorption of organic compounds has been realized, but whether these groups can generate different joint effects, especially when oxidized PCMs with different pore sizes are complexed with heavy metals (Cu2+), remains ambiguous. The present study aimed to determine how pore sizes, metal ions, and oxygen-containing groups as a function affect the sorption of naphthalene and 2-naphthol to PCMs (e.g., activated carbons/ACs and mesoporous carbon/CMK-3). The H2-reduced oxidized PCMs were used as the control of low oxygen content to avoid changes in the pore structure properties compared with the oxidized PCMs. Oxygen-containing groups considerably decreased the sorption of naphthalene and 2-naphthol to PCMs because of their weaker hydrophobic interaction and fewer sorption sites. Notably, naphthalene sorption on oxidized AC was inhibited with Cu2+ because of the steric constraint of Cu2+ hydration shells of the micropores. However, pore blockage by Cu2+ reduced the mesopore size of oxidized CMK-3, leading to enhanced pore filling effect and cation-π bonding, and therefore increased naphthalene sorption. For 2-naphthol, the sorption to oxidized PCMs initially increased and then decreased with increasing Cu2+ concentration attributed to the fewer Cu2+ acting as a bridging agent and excess Cu2+ competing for sorption sites.


Assuntos
Naftalenos , Oxigênio , Adsorção , Naftóis , Porosidade
17.
PLoS One ; 15(3): e0230753, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32218595

RESUMO

Rabbits (Oryctolagus cuniculi) are very popular as pets. However, problems of otitits caused by Psoroptes cuniculi are one of the main reasons to visit the veterinarian. Isoxazolines are an alternative treatment to treat this mite, and therefore, an evaluation of the effectiveness of oral afoxalaner with milbemycin oxime in rabbits infected with P. cuniculi was carried out. Nineteen rabbits, of New Zealand breed, with otitis due to an infection with P. cuniculi, were treated, whereas six rabbits were left untreated and formed the control group. The ear canals of each individual were examined, through the collection of otic exudate samples with cotton swabs. These were visualized under the microscope to identify the ectoparasite. Each animal was treated with a single oral dose of 2.50 mg / kg of afoxolaner, and 0.50 mg / kg of milbemycin oxime. Clinical signs and lesions associated with the infection, such as the presence of detritus, cerumen and / or scabs, and erythema, were evaluated. After receiving the treatment, all the lesions were classified as: mild, moderate and intense, with a visual analog scale. A week after providing medication, there was a decrease in the lesions of the group treated with Nexgard Spectra®, without further topical or systemic treatment. The decrease was gradual in the treated group and no recurrence was detected of P. cuniculi infection in both ears. Thus, the administration of a single oral dose of afoxolaner with milbemycin oxime was effective for the treatment of P. cuniculi infection in rabbits.


Assuntos
Isoxazóis/farmacologia , Macrolídeos/farmacologia , Infestações por Ácaros/tratamento farmacológico , Naftalenos/farmacologia , Psoroptidae/fisiologia , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Isoxazóis/uso terapêutico , Macrolídeos/uso terapêutico , Naftalenos/uso terapêutico , Coelhos
18.
Chemosphere ; 252: 126541, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32217411

RESUMO

Emission factor and removal efficacy of PCNs are evaluated via the flue gas sampling of two MWIs equipped with different air pollution control devices (APCDs) in Taiwan. MWI-A is equipped with ESP, wet scrubber (WS) and selective catalytic reduction (SCR), while cyclone (CY), semi-dry absorber (SDA), activated carbon injection (ACI) and baghouse (BH) are employed in MWI-B. The average concentrations of PCNs measured at stacks of MWI-A and MWI-B are 2.1 ng Nm-3 (0.218 pg TEQ Nm-3) and 23.2 ng Nm-3 (0.425 pg TEQ Nm-3), respectively. The emission factors of PCNs calculated from feeding rates of waste and stack sampling results range from 6.7 to 6.95 µg t-1 (0.790-1.45 ng TEQ t-1). PCNs are formed in ESP via chlorination, while SCR and SDA + ACI + BH are effective in removing PCNs with the overall efficacies of 97.6% and 94.3%, respectively. PCN removal efficiencies achieved with SCR and SDA + ACI + BH increase as chlorination level increases. Specifically, around 72% and 82% of Mono-CN are removed by SCR and SDA + ACI + BH, respectively. The removal efficacies of other homologues achieved with SCR are consistently high (96-100%). Dominances of Mono-to Tri-CNs in scrubbing liquid collected from WS and higher removal efficacies of these homologues achieved with WS + ESP compared with ESP alone indicate that WS can capture low chlorinated PCNs to some extent. The results suggest that CY + SDA + ACI + BH should be equipped in MWI for effective removal of PCNs, while ESP, WS and SCR should be utilized with precaution to eliminate PCNs formation and enhance the PCNs removal efficiency.


Assuntos
Monitoramento Ambiental , Incineração/métodos , Naftalenos/química , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Catálise , Taiwan
19.
Int J Nanomedicine ; 15: 1517-1535, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189966

RESUMO

Purpose: Dapoxetine HCl (DH), a selective serotonin reuptake inhibitor, may be useful for the treatment of rheumatic arthritis (RA). The purpose of this study was to investigate the therapeutic efficacy of transdermal delivery of DH in transethosome nanovesicles (TENVs). This novel delivery of DH may overcome the drawbacks associated with orally administered DH and improve patient compliance. Methods: DH-TENV formulations were prepared using an injection- sonication method and optimized using a 33 Box-Behnken-design with Design Expert® software. The TENV formulations were assessed for entrapment efficiency (EE-%), vesicle size, zeta potential, in vitro DH release, and skin permeation. The tolerability of the optimized DH-TENV gel was investigated using a rat skin irritation test. A pharmacokinetic analysis of the optimized DH-TENV gel was also conducted in rats. Moreover, the anti-RA activity of the optimized DH-TENV gel was assessed based on the RA-specific marker anti-cyclic cirtullinated peptide antibody (anti-CCP), the cartilage destruction marker cartilage oligomeric matrix protein (COMP) and the inflammatory marker interleukin-6 (IL-6). Level of tissue receptor activator of nuclear factor kappa-Β ligand (RANKL) were also assessed. Results: The optimized DH-TENV formulation involved spherical nanovesicles that had an appropriate EE- % and skin permeation characteristic. The DH-TENV gel was well tolerated by rats. The pharmacokinetics analysis showed that the optimized DH-TENV gel boosted the bioavailability of the DH by 2.42- and 4.16-fold compared to the oral DH solution and the control DH gel, respectively. Moreover, it significantly reduced the serum anti-CCP, COMP and IL-6 levels and decreased the RANKL levels. Furthermore, the DH-TENV gel attenuated histopathological changes by almost normalizing the articular surface and synovial fluid. Conclusion: The results indicate that DH-TENVs can improve transdermal delivery of DH and thereby alleviate RA.


Assuntos
Benzilaminas/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Naftalenos/uso terapêutico , Febre Reumática/tratamento farmacológico , Administração Cutânea , Animais , Benzilaminas/farmacocinética , Varredura Diferencial de Calorimetria , Feminino , Humanos , Articulações/diagnóstico por imagem , Articulações/patologia , Nanopartículas/ultraestrutura , Naftalenos/farmacocinética , Ligante RANK/metabolismo , Ratos Wistar , Febre Reumática/induzido quimicamente , Febre Reumática/diagnóstico por imagem , Febre Reumática/patologia , Testes de Irritação da Pele
20.
Invest Ophthalmol Vis Sci ; 61(3): 3, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32150246

RESUMO

Purpose: In the mammalian retina, cannabinoid type 1 receptors (CB1Rs) are well-positioned to alter inhibitory synaptic function from amacrine cells and, thus, might influence visual signal processing in the inner retina. However, it is not known if CB1R modulates amacrine cells feedback inhibition at retinal bipolar cell (BC) terminals. Methods: Using whole-cell voltage-clamp recordings, we examined the pharmacological effect of CB1R activation and inhibition on spontaneous inhibitory postsynaptic currents (sIPSCs) and glutamate-evoked IPSCs (gIPSCs) from identified OFF BCs in light-adapted rat retinal slices. Results: Activation of CB1R with WIN55212-2 selectively increased the frequency of GABAergic, but not glycinergic sIPSC in types 2, 3a, and 3b OFF BCs, and had no effect on inhibitory activity in type 4 OFF BCs. The increase in GABAergic activity was eliminated in axotomized BCs and can be suppressed by blocking CB1R with AM251 or GABAA and GABAρ receptors with SR-95531 and TPMPA, respectively. In all OFF BC types tested, a brief application of glutamate to the outer plexiform layer elicited gIPSCs comprising GABAergic and glycinergic components that were unaffected by CB1R activation. However, blocking CB1R selectively increased GABAergic gIPSCs, supporting a role for endocannabinoid signaling in the regulation of glutamate-evoked GABAergic inhibitory feedback to OFF BCs. Conclusions: CB1R activation shape types 2, 3a, and 3b OFF BC responses by selectively regulate GABAergic feedback inhibition at their axon terminals, thus cannabinoid signaling might play an important role in the fine-tuning of visual signal processing in the mammalian inner retina.


Assuntos
Receptor CB1 de Canabinoide/fisiologia , Células Bipolares da Retina/fisiologia , Células Amácrinas/metabolismo , Células Amácrinas/fisiologia , Animais , Benzoxazinas/farmacologia , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/fisiologia , Endocanabinoides/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Retroalimentação Fisiológica/fisiologia , Feminino , Antagonistas de Receptores de GABA-A/farmacologia , Ácido Glutâmico/farmacologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Morfolinas/farmacologia , Naftalenos/farmacologia , Técnicas de Patch-Clamp/métodos , Ácidos Fosfínicos/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/efeitos dos fármacos , Retina , Células Bipolares da Retina/efeitos dos fármacos , Transdução de Sinais/fisiologia
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