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A significant quantity of biologically produced sulfur (BPS) is generated as a by-product of chemical and biological desulfurization processes applied to landfill gas treatment. The beneficial upcycling of BPS has seen limited use in the environmental context. The effectiveness and underlying mechanism of BPS as an adsorbent for removing Hg2+ from both solution and wastewater were elucidated based on experiments encompassing surface characterization, adsorption isotherms, kinetics, and thermodynamics. The BPS exhibited remarkable efficacy in removing Hg2+ from solution, with the Langmuir model accurately describing the adsorption process and showing a maximum adsorption capacity of 244 mg g-1. Surface analysis through X-ray photoelectron spectroscopy and scanning electron microscopy revealed that Hg2+ complexed with sulfide on BPS surfaces, forming stable HgS. The adsorbed Hg was strongly retained in BPS, with less than 0.2% of the adsorbed Hg desorbed by strong acids. Adsorption kinetics followed the double-exponential first-order model, showing an initial rapid adsorption phase wherein 75% of the initial Hg2+ was removed within 5 min, followed by a slower adsorption rate. The thermodynamic parameters suggested that adsorption of Hg2+ by BPS was a spontaneous and endothermic process. Additionally, BPS effectively removed Hg2+ from wastewater, showing preference for Hg over other co-existing metals. These findings underscore the potential of BPS as an effective adsorbent for Hg2+ removal from wastewater.
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The alginate-biochar formulation for metal removal from aquatic environments has been widely tried but its use for lowering phytoavailability of metals in the soil-crop continuum is limited. Biochar has been increasingly used as a soil amendment due to its potential for soil carbon sequestration and sorption capacity. Handling of powdery biochar as a soil top-dressing material is, however, cumbersome and vulnerable to loss by water and wind. In this experiment, biochar powder, which was pyrolyzed from oak trees, was encapsulated into beads with alginate, which is a naturally occurring polysaccharide found in brown algae. Both batch and pot experiments were conducted to examine the effects of the alginate-encapsulated biochar beads (BB), as compared to its original biochar powdery form (BP), on the Pb adsorption capacity and phytoavailability of soil Pb to lettuce (Lactuca sativa L.). The BB treatment improved reactivity about six times due to a higher surface area (287 m2 g-1) and five times due to a higher cation exchange capacity (50 cmolc kg-1) as compared to the BP treatment. The maximum sorption capacity of Pb was increased to 152 from 81 mg g-1 because of surface chemosorption. Adsorption of Pb onto BB followed multiple first-order kinetics and comprised fast and slow steps. More than 60% of the Pb was adsorbed in the fast step, i.e., within 3 h. Also, the BB treatment, up to the 5% level (w/w), increased soil pH from 5.4 to 6.5 and lowered the phytoavailable fraction of Pb in soil from 5.7 to 0.3 mg kg-1. The Pb concentrations in lettuce cultivated at 5% for the BP and BB treatments were similar but 63 and 66% lower, respectively, than those of the control soil. The results showed that the encapsulation of biochar with alginate enhanced adsorption by the biochar.
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Lactuca , Contaminantes del Suelo , Plomo , Suelo , Alginatos , Contaminantes del Suelo/análisis , Carbón OrgánicoRESUMEN
A novel and streamlined approach to synthesizing benzotriazepin-1-ones has been developed through a hexafluoroisopropanol-promoted decarboxylative cascade reaction between isatoic anhydrides and hydrazonoyl chloride. The [4 + 3] annulation of hexafluoroisopropyl 2-aminobenzoates with nitrile imines, generated in situ, is a key feature of this innovative reaction. This approach has offered a simple and efficient method for synthesizing a broad range of structurally intricate and highly functional benzotriazepinones.
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To achieve a zero-carbon-emission society, it is essential to increase the use of clean and renewable energy. Yet, renewable energy resources present constraints in terms of geographical locations and limited time intervals for energy generation. Therefore, there is a surging demand for developing high-performance energy storage systems (ESSs) to effectively store the energy during the peak time and use the energy during the trough period. To this end, supercapacitors hold great promise as short-term ESSs for rapid power recovery or frequency regulation to improve the quality and reliability of power supply. In particular, the electrical double layer capacitor (EDLC) which offers long and stable cycle retention, high power densities, and fast charge/discharge characteristics with a moderate operating voltage window, is a suitable candidate. Yet, for implementation of the EDLC in ESSs, further research effort is required in terms of increasing the operating voltage and energy densities while maintaining the long-term cycle stability and power densities which are desirable aspects for ESS operation. Here, we examine the advances in EDLC research to achieve a high operating voltage window along with high energy densities, covering from materials and electrolytes to long-term device perspectives for next-generation supercapacitor-based ESSs.
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This study was conducted to evaluate the effects of different artificial light sources on the growth characteristics and various biological activities of the Atractylodes macrocephala x Atractylodes japonica hybrid cv. 'Dachul', which is highly useful for medicinal purposes. The plant had the largest biomass with a plant height of 38.20 ± 1.95 cm when treated with microwave electrodeless light (MEL). The chlorophyll content of the plants treated with fluorescent light (FL) was 53.93 ± 1.05 SPAD and was the highest. The antioxidant effect, determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), was the highest with 92.7 ± 0.2% in plants treated with light-emitting diode (LED)-green light. Total phenol and flavonoid contents were significantly higher with 19.7 ± 0.5 mg GAE/g and 40.2 ± 2.2 mg QE/g in the sample treated with LED-green light, respectively. For antimicrobial activity using the minimum inhibitory concentration (MIC) technique, the inhibitory ability against Escherichia coli was at 0.25 mg/mL under LED-green light treatment. The whitening activity using tyrosinase enzyme showed the highest tyrosinase inhibitory ability at 62.1 ± 1.2% of the above extract treated with MEL light. To confirm the immune activity in lipopolysaccharide (LPS)-induced RAW 264.7 cells, NO production of inflammation-related substances was measured. In addition, the inflammation-related genes iNOS (inducible nitric oxide synthase), COX-2 (cyclooxygenase-2), and TNF-α (tumor necrosis factor-α) in the same sample were confirmed using reverse transcriptase (RT)-PCR, and the result showed that gene expression was suppressed compared with that in the control group. It is expected that Dachul plants treated with LED-blue light will play an important role in enhancing intracellular anti-inflammatory activity. From these results, the effect for various biological activities appeared in a significantly diverse spectrum in response to different wavelengths of artificial light sources in Dachul.
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Synthesizing layered transition-metal carbides, MXenes, with a mesoporous structure remains challenging but is highly useful because it converts the laminated two-dimensional structures into versatile porous materials. Hydrogen bonds between intercalated H2O molecules and oxygen terminal groups on the surface are formed in aqueous solution processes, and this is a determining factor of surface area. We developed an extraction method to remove intercalated water molecules based on a simple intermolecular force attraction strategy in a co-solvent system using a combination of polar-protic/-aprotic and non-polar solvents. As a result, self-aggregated mesoporous Ti3C2Tx was realized without any additives. The dipole-dipole interaction between H2O and CHCl3 molecules under non-polar solvent conditions assists the extraction of intercalated H2O from the MXene suspension, which can form a self-aggregated morphology (not re-stacked horizontally). The process yields Ti3C2Tx with a layered structure of embedded mesopores and a specific surface area that is 13-fold higher than that of standard MXene. Electrodes made with the resulting MXene exhibited a larger specific capacitance of 224 F/g (1 A/g), with an improved cyclic retention of 96.4%@10,000 cycles. This intermolecular attraction-induced approach, involving the manipulation of morphology, is simple to mass-produce and can be used for MXene-based electrochemical applications.
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BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons in the substantia nigra. The purpose of this study was to examine neuroprotective effects of Hepad S1, an herbal medicine used for the treatment of PD, in in vitro and in vivo models of PD. METHODS: Differentiated neuronal PC12 cells underwent a cytotoxicity assay and oxidative stress analysis including DCF-DA staining, glutathione, and malondialdehyde, after exposure to 1-methyl-4-phenylpyridium (MPP+). Male Sprague-Dawley rats were used as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD models. After 4-week oral administration of Hepad S1 (200, 300, 400, and 500â¯mg/kg/day), the levels of complex enzyme I activity and dopamine, and dopaminergic neuronal cell number in substantia nigra were measured by enzyme linked immune-sorbent assay (ELISA) and microscopic observation, respectively. Circulating serotonin and orexin A were also examined by ELISA. RESULTS: Hepad S1 pretreatment prevented the ability of MPP+ challenge to decrease glutathione and increase lipid peroxidation in cells, indicating antioxidant activity. Hepad S1 recovered MPTP-induced decreases in complex I enzyme activity and enhanced dopamine availability in substantia nigra. Serum levels of serotonin and orexin A were increased by Hepad S1 treatment in model animals. Hepad S1 treatment was associated with the preservation of tyrosine hydroxylase-positive cells in the substantia nigra of MPTP-treated rats. CONCLUSIONS: Hepad S1 exerts antioxidant and neuroprotective effects on neurons of the substantia nigra in a rodent model of PD.
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PURPOSE: The purpose of this study was to examine types of parenting among fathers. The characteristics of parenting each type in early childhood were identified by systematically analyzing and classifying father's perceptions of parenting using the Q-methodology, which places importance on the perspective of the performer. METHODS: The Q-method, which is effective for measuring individual subjectivity was used. The subjects in this study were 50 fathers with young children (2~36 months). RESULTS: Four parenting types were identified analyzing the subjective perceptions of fathers with young children about parenting. One type was centered on character development. Another was centered on social development. A third was centered on physical health and development. The fourth was centered on building values. CONCLUSION: Parenting education programs should be developed based on type-specific characteristics and further research should investigate the effects of father's parenting type.
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Parkinson's disease (PD), a common adult-onset neurodegenerative disorder with complex pathological mechanisms, is characterized by the degeneration of dopaminergic nigrostriatal neurons. The present study demonstrated that the herbal medicines Hepad 1 and 2 protected against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurotoxicity in C57BL/6 mice and SH-SY5Y cells. Hepad 1 and 2 remarkably alleviated the enhanced expression of pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, cyclooxygenase-2, macrophage-1, and phosphorylated iκB-α) and apoptotic signals (Bcl-2-associated X protein, caspase-3, and poly [ADP-ribose] polymerase-1). Additionally, Hepad reduced MPTP-induced oxidative damage by increasing the expression of anti-oxidant defense enzymes (superoxide dismutase and glutathione S-transferase) and downregulating the levels of nicotinamide adenine dinucleotide phosphate oxidase 4. This study also showed that the neuroprotective effects of Hepad include anti-inflammatory, anti-apoptotic, and anti-oxidative properties, in addition to activation of the protein kinase B, extracellular-signal-regulated kinase, and c-Jun N-terminal kinase signaling pathways. Furthermore, oral administration of Hepad 1 and 2 attenuated the death of tyrosine hydroxylase-positive substantia nigra neurons that was induced by 20 mg/kg MPTP. Therefore, our results suggest that Hepad 1 and 2 are useful for treating PD and other disorders associated with neuro-inflammatory, neuro-apoptotic, and neuro-oxidative damage.
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1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/efectos adversos , Fármacos Neuroprotectores/administración & dosificación , Trastornos Parkinsonianos/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Plantas Medicinales/química , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Citocinas/metabolismo , Modelos Animales de Enfermedad , Medicina de Hierbas , Humanos , Ratones , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacologíaRESUMEN
Twenty pyrazole-containing diarylureas and diarylamides were designed and synthesized. They were tested for in vitro antiproliferative activity over a 58-cancer cell line panel at the NCI, USA. The diarylurea derivatives 1b-e and 1g exerted the strongest antiproliferative activity. Among them, compound 1e possessing 3,5-bis(trifluoromethyl)phenyl terminal ring and 3`-methoxy-5`-chlorophenyl ring attached to the central pyrazole ring was the most potent. Its IC50 values were in sub-micromolar range against most of the tested cell lines. It showed superior potency than sorafenib, a reference diarylurea drug, over all the tested cell lines. It was also extremely selective towards cancer cells than non-cancerous cells (IC50 against RAW 264.7 macrophages was higher than 100⯵M). At molecular level, compound 1e selectively inhibited V600E mutated B-RAF kinase (IC50â¯=â¯0.39⯵M). It also stimulated caspase 3/7 enzymes in RPMI-8226 leukemia cells (2.79 fold increase at 10⯵M concentration, EC50â¯=â¯1.52⯵M). So compound 1e may kill cancer cells through induction of apoptosis. This promising candidate can be considered further for development of new efficient anticancer agents.
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Antineoplásicos/química , Antineoplásicos/farmacología , Pirazoles/química , Pirazoles/farmacología , Urea/análogos & derivados , Urea/farmacología , Amidas/síntesis química , Amidas/química , Amidas/farmacología , Antineoplásicos/síntesis química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Humanos , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Pirazoles/síntesis química , Relación Estructura-Actividad , Urea/síntesis químicaRESUMEN
Ornithine decarboxylase (ODC) converts C5 ornithine into C4 putrescine, a monomer for polyamide synthesis. However, ODC also has minor activity towards cell metabolite C6 lysine and yields C5 cadaverine. The accumulation of cadaverine in the reaction solution causes increase in the operational cost of subsequent distillation process for putrescine purification. Here, to increase ODC substrate specificity toward ornithine over lysine, molecular modelling and protein network analysis, specifically k-clique community analysis, around the substrate tunnel were performed. This resulted in a mutant with two-fold increase in substrate specificity (ornithine versus lysine) without losing its original activity towards ornithine (kcat/KM⯠=â¯61.5â¯s-1 â¯mM-1), compared to the native enzyme. When this mutant was used for putrescine synthesis, 31.6â¯g/L putrescine (based on 51.5â¯g/L ornithine) titer was achieved, while 0.007â¯g/L (based on 2.57â¯g/L lysine) cadaverine was produced. This corresponds to four-fold decrease in cadaverine yield compared to the native ODC.
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Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Lisina/metabolismo , Ornitina Descarboxilasa/genética , Ornitina Descarboxilasa/metabolismo , Ornitina/metabolismo , Cadaverina/metabolismo , Escherichia coli/enzimología , Lactobacillus/enzimología , Modelos Moleculares , Mutación , Ingeniería de Proteínas , Putrescina/metabolismo , Saccharomyces cerevisiae/enzimología , Especificidad por SustratoRESUMEN
From graphene oxide wrapped iron oxide particles with etching/reduction process, high-performance anode and cathode materials of lithium-ion hybrid supercapacitors are obtained in the same process with different etching conditions, which consist of partially etched crumpled graphene (CG) wrapped spiky iron oxide particles (CG@SF) for a battery-type anode, and fully etched CG for a capacitive-type cathode. The CG is formed along the shape of spikily etched particles, resulting in high specific surface area and electrical conductivity, thus the CG-based cathode exhibits remarkable capacitive performance of 210 F g-1 and excellent rate capabilities. The CG@SF can also be ideal anode materials owing to spiky and porous morphology of the particles and tightly attached crumpled graphene onto the spiky particles, which provides structural stability and low contact resistance during repetitive lithiation/delithiation processes. The CG@SF anode shows a particularly high capacitive performance of 1420 mAh g-1 after 270 cycles, continuously increases capacity beyond the 270th cycle, and also maintains a high capacity of 170 mAh g-1 at extremely high speeds of 100 C. The full-cell exhibits a higher energy density up to 121 Wh kg-1 and maintains high energy density of 60.1 Wh kg-1 at 18.0 kW kg-1 . This system could thus be a practical energy storage system to fill the gap between batteries and supercapacitors.
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Cadaverine (1,5-diaminopentane) is a major source of many industrial polyamides such as nylon and chelating agents. Currently, cadaverine is produced by the microbial fermentation of glucose to lysine, which is then decarboxylated by lysine decarboxylase (CadA). However, utilizing CadA for cadaverine production causes enzyme instability. In order to stabilize the CadA homo-decamer structure for in vitro decarboxylation reaction, mutants are designed. Of the four disulfide bond mutants in the multimeric interfacial region, B1 (F14C/K44C) showed a 216-folds increase in the half-life of CadA at 60 °C. On top of B1, another round of mutant screening is performed around F14C and K44C to generate B1/L7M/N8G, which is then examined for cadaverine production (2M lysine and 10% v/v of cell-extract at 50 °C). The reaction pH increased from 4.9 to 8.3, and the final titer of the mutant is 157 g L-1 , that is, 76.7% conversion yield in 9.5 h, whereas the wild-type gave 119 g L-1 , that is, 58.2% conversion yield in 9.5 h.
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Cadaverina/metabolismo , Carboxiliasas/química , Carboxiliasas/metabolismo , Lisina/metabolismo , Ingeniería Metabólica/métodos , Cadaverina/análisis , Carboxiliasas/genética , Clonación Molecular , Estabilidad de Enzimas , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Modelos Moleculares , Mutagénesis Sitio-DirigidaRESUMEN
Veterinary antibiotics are available for uptake by the plants through sources such as manure, irrigation, and atmospheric interaction. The present study was conducted to estimate the half-lives of three veterinary antibiotics, chlortetracycline (CTC), enrofloxacin (ENR), and sulphathiazole (STZ), in soil and experimentally explore their uptake from contaminated soil to radish roots and leaves. Samples were extracted using a modified citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe "QuEChERS" method followed by liquid chromatography coupled with tandem mass spectrometric analysis (LC-MS/MS) in the positive ion mode. Good linearity was observed for the three tested antibiotics in soil and plants (roots and leaves) with high coefficients of determination (R2≥0.9922). The average recovery rates at two spiking levels with three replicates per level ranged between 77.1 and 114.8%, with a relative standard deviation (RSD)≤19.9% for all tested drugs. In a batch incubation experiment (in vitro study), the half-lives of CTC, ENR, and STZ ranged from 2.0-6.1, 2.2-4.5, and 1.1-2.2days, respectively. Under greenhouse conditions, the half-lives of the three target antibiotics in soil with and without radishes were 2.5-6.9 and 2.7-7.4; 4.7-16.7 and 10.3-14.6; and 4.4-4.9 and 2.5-2.8days, respectively. Trace amounts of the target antibiotics (CTC, ENR, and STZ) were taken up from soil via roots and entered the leaves of radishes. The concentration of CTC was lower than 2.73%, ENR was 0.08-3.90%, and <1.64% STZ was uptaken. In conclusion, the concentrations of the tested antibiotics decreased with time and consequently lower residues were observed in the radishes. The rapid degradation of the tested antibiotics in the present study might have only little impact on soil microorganisms, fauna, and plants.
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Antibacterianos/metabolismo , Raphanus/metabolismo , Contaminantes del Suelo/metabolismo , Drogas Veterinarias/metabolismo , Clortetraciclina/metabolismo , Cromatografía Liquida , Enrofloxacina , Fluoroquinolonas/metabolismo , Hojas de la Planta/química , Raíces de Plantas/química , Suelo/química , Sulfatiazoles/metabolismo , Espectrometría de Masas en TándemRESUMEN
We present an image-guided laparoscopic surgical tool (IGLaST) to prevent bleeding. By applying optical frequency domain imaging (OFDI) to a specially designed laparoscopic surgical tool, the inside of fatty tissue can be observed before a resection, and the presence and size of blood vessels can be recognized. The optical sensing module on the IGLaST head has a diameter of less than 390 µm and is moved back and forth by a linear servo actuator in the IGLaST body. We proved the feasibility of IGLaST by in vivo imaging inside the fatty tissue of a porcine model. A blood vessel with a diameter of about 2.2 mm was clearly observed. Our proposed scheme can contribute to safe surgery without bleeding by monitoring vessels inside the tissue and can be further expanded to detect invisible nerves of the laparoscopic thyroid during prostate gland surgery.
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Laparoscopía , Animales , Imagen Óptica , Porcinos , Tomografía de Coherencia ÓpticaRESUMEN
BACKGROUND: The prevalence of metabolic syndrome (MetS) has been increasing among Koreans, and middle-aged and older women are at risk of metabolic syndrome. Effective strategies to promote lifestyle modification need to be developed. OBJECTIVE: We examined the effects of a self-management program on improving the cardiovascular health status and promoting healthy behaviors among overweight or obese Korean women at risk of metabolic syndrome. METHODS: A pretest and posttest intervention design was used. Sixty women participated in a group teaching session. They also received a pedometer and a diary for self-monitoring. On the basis of blood test results, women's metabolic syndrome status was identified. Thirty women with metabolic syndrome received additional tailored counseling and weekly follow-up calls for 4 weeks, whereas 30 women without metabolic syndrome did not receive any tailored counseling or follow-up calls. Twenty-three women in the MetS group and 22 women in the non-MetS group completed the posttest. RESULTS: Overall, women significantly improved their cardiovascular health status including systolic blood pressure, diastolic blood pressure, body mass index, low-density lipoprotein, triglycerides, number of metabolic syndrome risk factors, and 10-year risk estimates from pretest to posttest. Seventy-eight percent of the MetS group (n = 18) no longer had metabolic syndrome, whereas 5% of the non-MetS group (n = 1) became to have metabolic syndrome. Women significantly increased frequency and duration of walking per week and significantly decreased the time spent sitting. CONCLUSIONS: Promoting self-management for healthy behaviors might be effective for obese or overweight women to prevent metabolic syndrome and cardiovascular diseases, if it is tailored to their health needs.
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Pueblo Asiatico , Conductas Relacionadas con la Salud , Síndrome Metabólico/prevención & control , Obesidad/terapia , Automanejo , Adulto , Anciano , Dieta , Femenino , Humanos , Síndrome Metabólico/etiología , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/etnología , República de Corea , CaminataRESUMEN
For monitoring and risk assessment, levels and distributions of Σ29 PCBs in paddy soil samples collected from Gwangyang (10 sites) and Ulsan (20 sites), heavily industrialized cities in Korea, were investigated using high-resolution gas chromatography/high-resolution mass spectrometry. Overall, total concentrations of Σ29 PCBs in Gwangyang (216.4-978.6 pg g-1 dw) and Ulsan (273.8-1824.1 pg g-1 dw) were higher than those (106.6-222.6 pg g-1 dw) in agricultural soil from Anseong in Korea. The TEQ (toxic equivalency) values from Gwangyang (0.06-0.40 ng TEQ kg-1 dw) and Ulsan (0.06-0.22 ng TEQ kg-1 dw) were higher than those (0.04-0.11 ng TEQ kg-1 dw) in Anseong but lower than the WHO threshold level (20 ng TEQ kg-1). However, one of the most toxic congeners, PCB 126, gave the highest concentration, possibly posing a risk to the biota. Seven indicator PCB congeners contributed to 50-80% of the total concentration of Σ29 PCBs, indicating the 7 PCBs can be used as valuable indicators for monitoring. The principal component analysis and cluster analysis for the homologue profiles of PCBs indicated that all the samples from both cities had the similar PCB contamination patterns, and the major sources of the PCB contamination were most likely from the usage of Aroclor 1254 than those of Aroclors 1242 and 1260. These PCB technical mixtures were possibly significantly used by various industries including iron and steel industries in Gwangyang and petrochemical and shipbuilding industries in Ulsan.
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Monitoreo del Ambiente/métodos , Bifenilos Policlorados/análisis , Medición de Riesgo/métodos , Contaminantes del Suelo/análisis , Agricultura , Ciudades , Cromatografía de Gases y Espectrometría de Masas/métodos , Industrias , Bifenilos Policlorados/toxicidad , Análisis de Componente Principal , República de Corea , Contaminantes del Suelo/toxicidadRESUMEN
This study was undertaken to develop and validate a single multiresidue method for the monitoring of ten multiclass emerging contaminants, viz. ceftiofur, clopidol, florfenicol, monensin, salinomycin, sulfamethazine, sulfathiazole, sulfamethoxazole, tiamulin, and tylosin in agricultural soil. Samples were extracted using an acetate-buffered, modified quick, easy, cheap, effective, rugged, and safe method followed by liquid chromatography with tandem mass spectrometric analysis in positive ion mode. Separation on an Eclipse Plus C18 column was conducted in gradient elution mode using a mobile phase of methanol (A) and distilled water (B), each containing 0.1% formic acid and 5 mM ammonium formate. The linearity of the matrix-matched calibrations, expressed as determination coefficients, was good, with R2 ≥ 0.9908. The limits of quantification were in the range 0.05-10 µg/kg. Blank soil samples spiked with 4 × and 20 × the limit of quantification provided recovery rates of 60.2-120.3% (except sulfamethoxazole spiked at 4 × the limit of quantification, which gave 131.9%) with a relative standard deviation < 13% (except clopidol spiked at 20 × the limit of quantification, which gave 25.2%). This method was successfully applied to the monitoring of 51 field-incurred agricultural loamy-sand soil samples collected from 17 provincial areas throughout the Korean Peninsula. The detected and quantified drugs were clopidol (≤ 4.8 µg/kg), sulfathiazole (≤ 7.7 µg/kg), sulfamethazine (≤ 6.6 µg/kg), tiamulin (≤ 10.0 µg/kg), and tylosin (≤ 5.3 µg/kg). The developed method is simple and versatile, and can be used to monitor various classes of veterinary drugs in soil.
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Cromatografía Liquida , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Suelo/química , Espectrometría de Masas en Tándem , Acetatos/química , Límite de Detección , República de Corea , Drogas Veterinarias/análisisRESUMEN
This study was performed to understand how chlorpyrifos (CHL) affects zebrafish (Danio rerio) embryos and adults, by exposing this model organism to various concentrations of the insecticide. The 96-h acute toxicity test to determine the effect of CHL on adult zebrafish yielded a LC50 of 709.43µg/L(-1). Small molecular weight proteins less than 25kDa and phospholipids were analyzed with MALDI-TOF MS/MS in order to compare expression patterns, revealing that some peaks were dramatically altered after CHL treatment. Whereas no acute toxicity was detected in the embryo toxicity test, malformation of zebrafish larvae was observed, with many individuals harboring curved spines. In an angiogenesis test on larvae of transgenic zebrafish, CHL did not have an inhibitory effect. Relative gene expression analyses using real-time polymerase chain reaction (RT-PCR) of DNA from zebrafish embryos revealed that different subtypes of cytochrome P450 (CYP450), such as CYP1A and CYP3A, were significantly up-regulated in response to CHL at a concentration of 400µg/L(-1) compared to the control. The expression level of NR1I2, a CYP gene transcriptional regulator, UGT1a1, and MDR1 were all up-regulated in the CHL-treated embryos. Finally, the expression level of acetylcholinesterase (AChE) and catalase (CAT) decreased, whereas that of superoxide dismutase (SOD) did not differ significantly. Our results suggest that the up-regulation of metabolic enzymes including CYP450 and MDR1 may be involved in CHL resistance in zebrafish.
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Cloropirifos/toxicidad , Insecticidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Acetilcolinesterasa/metabolismo , Animales , Biomarcadores/metabolismo , Catalasa/metabolismo , Embrión no Mamífero , Monitoreo del Ambiente , Reacción en Cadena en Tiempo Real de la Polimerasa , Superóxido Dismutasa/metabolismo , Pez Cebra/embriología , Pez Cebra/fisiologíaRESUMEN
Biochar has been recently considered as a candidate for soil amendment and soil remediation. Some pollutants have been screened in the biochar for safety purposes except for perfluorochemicals (PFCs). In this study, the contamination of biochars from plant residues and sewage sludge with perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) was examined. The total residual concentrations of PFOA and PFOS in the sludge biochar were 15.8-16.9 ng/g and these values did not decrease significantly after pyrolysis. On the other hand, these PFCs were not found in the biochar from plant sources. In conclusion, the use of the sludge biochar in the agricultural environment should be re-evaluated, since the concentrations of PFCs in the sewage sludge showed no significant decrease after thermal process.