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1.
Environ Sci Technol ; 56(14): 10239-10248, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35790344

RESUMEN

Extremely high levels of decabromodiphenyl ether (BDE-209) are frequently found in the serum of occupationally exposed groups, such as e-waste dismantlers and firefighters. However, the metabolism of BDE-209 in the human body is not adequately studied. In this study, 24 serum samples were collected from workers at a typical e-waste recycling workshop in Taizhou, Eastern China, and the occurrence and fate of these higher brominated diphenyl ethers (PBDEs) were investigated. The median concentration of the total PBDEs in the serum was 199 ng/g lipid weight (lw), ranging from 125 to 622 ng/g lw. Higher brominated octa- to deca-BDEs accounted for more than 80% of the total PBDEs. Three ortho-hydroxylated metabolites of PBDEs─6-OH-BDE196, 6-OH-BDE199, and 6'-OH-BDE206─were widely detected with a total concentration (median) of 92.7 ng/g lw. The concentrations of the three OH-PBDEs were significantly higher than their octa- and nona-PBDE homologues, even exceeding those of the total PBDEs in several samples, indicating that the formation of OH-PBDEs was a major metabolic pathway of the higher brominated PBDEs in occupationally exposed workers. An almost linear correlation between 6-OH-BDE196 and 6-OH-BDE199 (R = 0.971, P < 0.001) indicates that they might undergo a similar biotransformation pathway in the human body or may be derived from the same precursor. In addition, the occurrence of a series of penta- to hepta- ortho-substituted OH-PBDEs was preliminarily identified according to their unique "predioxin" mass spectral profiles by GC-ECNI-MS. Taken together, the tentative metabolic pathway for BDE-209 in e-waste dismantlers was proposed. The oxidative metabolism of BDE-209 was mainly observed at the ortho positions to form 6'-OH-BDE-206, which later underwent a consecutive loss of bromine atoms at the meta or para positions to generate other ortho-OH-PBDEs. Further studies are urgently needed to identify the chemical structures of these ortho-OH-PBDE metabolites, and perhaps more importantly to clarify the potentially toxic effects, along with their underlying molecular mechanisms.


Asunto(s)
Residuos Electrónicos , Éteres Difenilos Halogenados , Biotransformación , Residuos Electrónicos/análisis , Monitoreo del Ambiente , Éteres Difenilos Halogenados/análisis , Humanos
2.
Environ Sci Technol ; 54(9): 5489-5497, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32264671

RESUMEN

Tris(2-chloroethyl) phosphate (TCEP), a typical chlorinated organophosphate ester (OPE), is an emerging contaminant of global concern because of its frequent occurrence, potential toxic effects, and persistence in the environment. In this study, we investigated the microbial TCEP biotransformation and the development of microbial communities in sediment microcosms with repeated TCEP amendments. The TCEP degradation fitted pseudo-zero-order kinetics, with reaction rates of 0.068 mg/(L h) after the first spike of 5 mg/L and 1.85 mg/(L h) after the second spike of 50 mg/L. TCEP was mainly degraded via phosphoester bond hydrolysis, evidenced by the production of bis(2-chloroethyl) phosphate (BCEP) and mono-chloroethyl phosphate (MCEP). Bis(2-chloroethyl) 2-hydroxyethyl phosphate (TCEP-OH), phosphoric bis(2-chloroethyl) (2-oxoethyl) ester (TCEP-CHO), phosphoric acid bis(2-chloroethyl)(carboxymethyl) ester (TCEP-COOH), and 2-chloroethyl 2-hydroxyethyl hydrogen phosphate (BCEP-OH) were also identified as microbial TCEP transformation products, indicating that TCEP degradation may follow hydrolytic dechlorination and oxidation pathways. Microbial community compositions in TCEP-amended microcosms shifted away from control microcosms after the second TCEP spike. Burkholderiales and Rhizobiales were two prevalent bacterial guilds enriched in TCEP-amended microcosms and were linked to the higher abundances of alkaline and acid phosphatase genes and genes involved in the metabolism of 2-chloroethanol, a side product of TCEP hydrolysis, indicating their importance in degrading TCEP and its metabolites.


Asunto(s)
Retardadores de Llama , Microbiota , Biotransformación , Organofosfatos , Fosfatos , Fosfinas
3.
Ecotoxicol Environ Saf ; 183: 109564, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31442805

RESUMEN

Surface and columnar sediments were collected from four mangrove Wetlands in Shantou coastal areas of South China to investigate the level, distribution, possible sources and ecotoxicological risks of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). Total concentration of 14 PBDEs (∑14PBDEs) and 41 PCBs (∑41PCBs) varied from 0.61 to 180 ng/g and 42-636 pg/g dry weight (dw) in surface sediments, respectively. The concentration of PBDEs was much higher than that of PCBs. Compared with other mangrove Wetlands around the world, PCBs levels in the studied area were relatively low, while the concentrations of PBDE were at higher level. Decabromodiphenyl ether (BDE-209) was the predominant PBDEs homologue in all sediment samples, indicating the extensive use of deca-BDE in this area. Penta-CBs and hexa-CBs were the main homologues of PCBs. Spatial variations showed that the concentration of PBDEs might be mainly affected by anthropogenic activities in specific sites of this region, whereas dry and wet deposition might be an important input source of PCBs in this area. Although accurate sediment chronology was not available, higher concentrations of PBDEs and PCBs were still found in some deeper sediment layers, suggesting that new input quantity tends to decrease with the increase of control. Risk assessment showed that penta-BDEs and deca-BDE may have potential negative ecological effects on the ecological of Shantou mangrove sediments, while the effects of PCBs can be neglected.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Éteres Difenilos Halogenados/análisis , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Humedales , China , Ecotoxicología , Medición de Riesgo
4.
Int J Phytoremediation ; 21(12): 1190-1196, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31119945

RESUMEN

The rehabilitation of soil co-contaminated by heavy metals and polycyclic aromatic hydrocarbons (PAHs) has become a serious global issue. Chemical enhancers and strains are often used to remove PAHs from contaminated soil. In this paper, the effects of chemical enhancers, strain HD-1, and Scirpus triqueter in removing pyrene from co-contaminated soil are studied. In the pot experiment, chemical enhancers and HD-1 were added to the co-contaminated soil. On the 60th day, the plants and soil were taken out for measurement. The result showed that the addition of chemical enhancers and microorganisms (Group PBC) alleviated the inhibition effect of plants on pollution. The accumulation of pyrene in plants of Group PC (chemical enhancers) and Group PBC (chemical enhancers and HD-1) were much higher than those in other groups. Plant enrichment was not the major way to remove pyrene from soil (less than 0.3%). Compared with the contributions of chemical enhancers, HD-1, and Scirpus triqueter, HD-1 had stronger effects on the removal of pyrene (17.23-22.80%). This study indicates that the combination of chemical enhancers, HD-1, and Scirpus triqueter constituted a beneficial composite system, in which the three elements interacted with each other and ultimately achieved the goal of removing pyrene from co-contaminated soil.


Asunto(s)
Cyperaceae , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Biodegradación Ambiental , Pirenos , Suelo , Microbiología del Suelo
5.
J Environ Manage ; 246: 289-298, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31181478

RESUMEN

Ambient black carbon (BC) is found to be associated with increased risk of diverse pulmonary diseases, including acute respiratory inflammation and decreased lung function. Freshly emitted BC (FBC) can be transformed into oxidized BC (OBC) through the photochemical oxidization in the air. How this oxidization process influences the toxicity of BC particles is unclear. Previous studies found FBC and OBC could induce oxidative stress and inflammation. This study aimed to further compare the regulating pathways and tried to reveal the crucial target genes caused by FBC and OBC in A549 cells based on transcriptomic data. A total of 47,000 genes in A549 cells after treated with FBC and OBC were examined using Affymetrix Human U133 plus 2.0 chips. Gene ontology (GO) classification (functional enrichment of differentially expressed genes) and Kyoto encyclopedia of genes and genomes (KEGG) classification (pathway enrichment of differentially expressed genes) were conducted and crucial genes were screened. The results showed that top 50 GO terms of FBC and OBC were not completely consistent. The Go term of cation channel was only identified in OBC group, probably caused by the characteristic that zeta potential of OBC is negative, while, that of FBC is positive. In addition transient receptor potential melastatin 7 (trpm7) gene was suggested to be closely related to this process caused by OBC. There are 47 identical pathways in FBC and OBC group among the top 50 KEGG. The inconsistent pathways are mostly related to inflammation with different up-regulation or down-regulation trends of crucial genes. The KEGG results suggested that FBC and OBC both cause inflammatory responses, but through different regulating pathways. In conclusion, OBC and FBC could induce similar toxic endpoints in A549 cells, but the underline regulating processes are not exactly the same.


Asunto(s)
Estrés Oxidativo , Transcriptoma , Células A549 , Carbono , Humanos , Oxidación-Reducción
6.
Cell Physiol Biochem ; 45(1): 267-280, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29357323

RESUMEN

BACKGROUND/AIMS: Prostate cancer (PCa) is the second most frequently diagnosed cancer in men worldwide. Currently available therapies for hormone-refractory PCa are only marginally effective. Plumbagin (PLB), a natural naphthoquinone isolated from the traditional folk medicine Plumbago zeylanica, is known to selectively kill tumor cells. Nevertheless, antitumor mechanisms initiated by PLB in cancer cells have not been fully defined. METHODS: MTT assay was used to evaluate the effect of PLB on the viability of cancer cells. Cell apoptosis and reactive oxygen species (ROS) production were determined by flow cytometry. Protein expression was detected by western blotting. In vivo anti-tumor effect was measured by using tumor xenoqraft model in nude mice. RESULTS: In the present study, we found that PLB decreases cancer cell growth and induces apoptosis in DU145 and PC-3 cells. In addition, by increasing intracellular ROS levels, PLB induced a lethal endoplasmic reticulum stress response in PCa cells. Importantly, blockage of ROS production significantly reversed PLB-induced ER stress activation and cell apoptosis. In vivo, we found that PLB inhibits the growth of PCa xenografts without exhibiting toxicity Treatment of mice bearing human PCa xenografts with PLB was also associated with induction of ER stress activation. CONCLUSION: Inducing ER stress by PLB thus discloses a previously unrecognized mechanism underlying the biological activity of PLB and provides an in-depth insight into the action of PLB in the treatment of hormone-refractory PCa.


Asunto(s)
Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Naftoquinonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Factor de Transcripción Activador 4/metabolismo , Animales , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Naftoquinonas/química , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Interferencia de ARN , Factor de Transcripción CHOP/antagonistas & inhibidores , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/metabolismo , Trasplante Heterólogo , eIF-2 Quinasa/metabolismo
7.
Cell Physiol Biochem ; 47(1): 129-139, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29763918

RESUMEN

BACKGROUND/AIMS: Transplantation of bone-marrow-derived mesenchymal stem cells (MSCs) promotes neural cell regeneration after spinal cord injury (SCI). Recently, we showed that suppression of microRNA-383 (miR-383) in MSCs increased the protein levels of glial cell line derived neurotrophic factor (GDNF), resulting in improved therapeutic effects on SCI. However, the overall effects of miR-383 suppression in MSCs on SCI therapy were not determined yet. Here, we addressed this question. METHODS: We used bioinformatics tools to predict all miR-383-targeting genes, confirmed the functional bindings in a dual luciferase reporter assay. The effects of alteration of candidate genes in MSCs on cell proliferation were analyzed by MTT assay and by Western blotting for PCNA. The effects on angiogenesis were assessed by HUVEC assay. The effects on SCI in vivo were analyzed by transplantation of the modified MSCs into nude rats that underwent SCI. RESULTS: Suppression of miR-383 in MSCs not only upregulated GDNF protein, but also increased vascular endothelial growth factor A (VEGF-A) and cyclin-dependent kinase 19 (CDK19), two other miR-383 targets. MiR-383-suppression-induced increases in CDK19 resulted in a slight but significant increase in MSC proliferation, while miR-383-suppression-induced increases in VEGF-A resulted in a slight but significant increase in MSC-mediated angiogenesis. CONCLUSIONS: Upregulation of CDK19 and VEGF-A by miR-383 suppression in MSCs further improve the therapeutic potential of MSCs in treating SCI in rats.


Asunto(s)
Regulación de la Expresión Génica , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , Traumatismos de la Médula Espinal/terapia , Adulto , Animales , Proliferación Celular , Células Cultivadas , Regulación hacia Abajo , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Neovascularización Fisiológica , Ratas , Ratas Desnudas , Traumatismos de la Médula Espinal/genética , Factor A de Crecimiento Endotelial Vascular/genética
8.
Med Sci Monit ; 23: 1923-1932, 2017 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-28430763

RESUMEN

BACKGROUND The aim of the current study was to explore the anti-arthritic effect of pinitol via assessing its effect on various inflammatory mediators and its possible mechanism of action. MATERIAL AND METHODS We assessed the anti-arthritic effect of pinitol in a formaldehyde- and CFA-induced arthritic model in Wistar Swiss albino strain rats divided into 6 groups. The rats received different doses of pinitol and indomethacin for 28 days. The arthritic index and body weight were determined at regular intervals, together with hepatic, hematological, and antioxidant parameters. The expression of proinflammatory cytokines (e.g., IL-6, TNF-α, and IL-1ß) and inflammatory mediators (e.g., COX-2 and VEGF) were also estimated with histopathological evaluation of the joint tissue of rats. A docking study of pinitol with PTPN22 was also carried out. RESULTS The CFA-induced model rats developed redness and nodules in the tail and front paws, and the arthritic control (AC) group rats showed similar symptoms, which were decreased by pinitol administration. The body weight of AC group rats was decreased, while pinitol-treated rats showed considerably increased body weight. Hematological, hepatic, and antioxidant parameters were altered by pinitol in a dose-dependent manner. Pinitol significantly decreased the elevated concentration of proinflammatory cytokines and inflammatory mediators, with improvement in histopathological condition. The docking study suggested that pinitol efficiently interacted with PTPN22 via Arg59, Tyr60, Leu106, and Lys138 by creating close interatomic hydrogen bonds and hydrophobic contacts. CONCLUSIONS Pinitol showed anti-arthritic effects via reduction of proinflammatory cytokines and inflammatory mediators via inhibition of PTPN22.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Inositol/análogos & derivados , Proteína Tirosina Fosfatasa no Receptora Tipo 22/antagonistas & inhibidores , Animales , Antioxidantes/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Indometacina/uso terapéutico , Mediadores de Inflamación/metabolismo , Inositol/metabolismo , Inositol/farmacología , Inositol/uso terapéutico , Masculino , Extractos Vegetales/uso terapéutico , Proteína Tirosina Fosfatasa no Receptora Tipo 22/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Ratas , Ratas Wistar
9.
Zhonghua Yi Xue Za Zhi ; 95(40): 3305-7, 2015 Oct.
Artículo en Zh | MEDLINE | ID: mdl-26815354

RESUMEN

OBJECTIVE: To investigate the optimal treatment and prognostic factors of renal cell carcinoma with brain metastases (RCCBM) by the analysis of clinical features. METHODS: The clinical data of 10 patients with RCCBM in our hospital from Jul. 2003 to Aug. 2011 were analyzed retrospectively. The age range of the patients was 48-80 years, and the mean age was 64 years old. Nine patients were male and one patient was female. Six patients had neurological symptoms. Brain metastasis and kidney cancer were found in the same period in 7 patients. Two patients had brain metastases alone, and 8 patients had metastasis in brain and other parts. There were 4 patients had more than 3 brain metastatic foci. Brain metastatic foci located in: frontal lobe in 6 patients, parietal lobe in 2 patients, occipital lobe in 2 patients, cerebellum in 2 patients, temporal lobe in 1 patient, thalamus and basal ganglia in 1 patient. RESULTS: The overall survival (OS) of 10 patients with RCCBM was 0.8 to 62.6 months, with an average OS of 12.7 months. Two patients refused therapy and those average OS is only 1.4 months. Three patients were performed stereotactic radiotherapy (SRS). The tumor volume of 1 patient reduced >25% and 2 patients showed no progression in magnetic resonance images at 2-months after SRS. Two patients accepted sorafenib treatment and the average OS was 16.7 months. Patients with 3 or more brain metastases had an average OS of 1.9 months, and the average OS of those with less than 3 brain metastases was 20 months. Patients with synchronous or metachronous brain metastases of renal cell carcinoma had an average OS of 6.8 or 26.5 months, respectively. Patients with or without neurological symptoms had an average OS of 17.9 or 4.9 months, respectively. CONCLUSIONS: For RCCBM patients, SRS could effectively control the local brain metastases while sorafenib could extend the overall survival. With 3 or more metastases, synchronous brain metastases and no neurological symptoms were the adverse prognostic factors of RCCBM.


Asunto(s)
Neoplasias Encefálicas , Carcinoma de Células Renales , Neoplasias Renales , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Células Epiteliales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radiocirugia , Estudios Retrospectivos
10.
Sci Total Environ ; 912: 169226, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38101627

RESUMEN

Recent screening surveys have shown the presence of unknown source halogenated organic compounds (HOCs) in shale gas wastewater. However, their occurrence, profile, transport in surrounding surface water and environmental risk potentials remain unclear. Here, a method for the extraction and quantitative determination of 13 HOCs in water by solid phase extraction combined with gas chromatography-mass spectrometry (GC-MS) was established. All of the targeted HOCs were detected and peaked at the outfall, while these contaminants were generally not detected in samples upstream of the outfall, suggesting that these contaminants originated from the discharge of shale gas wastewater; this was further supported by the fact that these pollutants were generally detected in downstream samples, with a tendency for pollutant concentrations to decrease progressively with increasing distance from the outfall. However,different HOCs had different transport potential in water. In addition, the toxicological effects of typical HOCs were evaluated using HepG2 as a model cell. The results indicated that diiodoalkanes suppressed HepG2 cell proliferation and induced ROS generation in a concentration-dependent manner. Mechanistic studies showed that diiodoalkanes induced apoptosis in HepG2 cells via the ROS-mediated mitochondrial pathway, decreasing mitochondrial membrane potential and increasing intercellular ATP and Ca2+ levels. On the other hand, RT-qPCR and Western blot assays revealed that the SLC7A11/GPX4 signaling pathway and HO-1 regulation of ferritin autophagy-dependent degradation (HO-1/FTL) pathway were involved in the ferroptosis pathway induced by diiodoalkane in HepG2 cells. Our study not only elucidates the contamination profiles and transport of HOCs in surface water of typical shale gas extraction areas in China, but also reveals the toxicity mechanism of typical diiodoalkane.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/toxicidad , Gas Natural/análisis , Especies Reactivas de Oxígeno/análisis , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Compuestos Orgánicos , Agua/análisis , China
11.
Food Funct ; 15(8): 4021-4036, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38584465

RESUMEN

Several mechanisms underlying nephrolithiasis, one of the most common urological diseases, involve calcium oxalate formation, including oxidative stress, inflammatory reactions, fibrosis, pyroptosis, and apoptosis. Although lycopene has strong antioxidant activity, its protective effects against CaOx-induced injury have not yet been reported. This study aimed to systematically investigate the protective effects of lycopene and explore its mechanisms and molecular targets. Crystal deposition, renal function, oxidative stress, inflammatory response, fibrosis, pyroptosis, and apoptosis were assessed to evaluate the renoprotective effects of lycopene against crystal formation in a CaOx rat model and oxalate-stimulated NRK-52E and HK-2 cells. Lycopene markedly ameliorated crystal deposition, restored renal function, and suppressed kidney injury by reducing oxidative stress, apoptosis, inflammation, fibrosis, and pyroptosis in the rats. In cell models, lycopene pretreatment reversed reactive oxygen species increase, apoptotic damage, intracellular lactate dehydrogenase release, cytotoxicity, pyroptosis, and extracellular matrix deposition. Network pharmacology and proteomic analyses were performed to identify lycopene target proteins under CaOx-exposed conditions, and the results showed that Trappc4 might be a pivotal target gene for lycopene, as identified by cellular thermal shift assay and surface plasmon resonance analyses. Based on molecular docking, molecular dynamics simulations, alanine scanning mutagenesis, and saturation mutagenesis, we observed that lycopene directly interacts with Trappc4 via hydrophobic bonds, which may be attributed to the PHE4 and PHE142 residues, preventing ERK1/2 or elevating AMPK signaling pathway phosphorylation events. In conclusion, lycopene might ameliorate oxalate-induced renal tubular epithelial cell injury via the Trappc4/ERK1/2/AMPK pathway, indicating its potential for the treatment of nephrolithiasis.


Asunto(s)
Apoptosis , Fibrosis , Licopeno , Nefrolitiasis , Estrés Oxidativo , Piroptosis , Ratas Sprague-Dawley , Solanum lycopersicum , Licopeno/farmacología , Nefrolitiasis/metabolismo , Nefrolitiasis/tratamiento farmacológico , Animales , Estrés Oxidativo/efectos de los fármacos , Ratas , Piroptosis/efectos de los fármacos , Apoptosis/efectos de los fármacos , Masculino , Solanum lycopersicum/química , Humanos , Oxalato de Calcio/metabolismo , Oxalato de Calcio/química , Línea Celular , Riñón/efectos de los fármacos , Riñón/metabolismo , Inflamación/metabolismo , Sustancias Protectoras/farmacología
12.
Ecotoxicol Environ Saf ; 84: 325-33, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22921253

RESUMEN

The concentrations of musks (polycyclic musks and nitro musks) and traditional organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane and its metabolites (DDT, DDE, DDD, and total DDTs), hexachlorobenzene (HCB), and hexachlorocyclohexanes (HCHs) in breast milk collected in Shanghai, China during the period 2006-2010, were determined. The total concentrations ranged from 4.7 to 276.2 (median: 58.4) ng/glipid weight (lw) for musks and from 88.3 to 2532.9 (median: 1003.8) ng/glw for OCPs. 4,4'-DDE (median: 655.4 ng/glw) was the predominant OCP, followed by ß-HCH (median: 172.5 ng/g lw), and HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[γ]-2-benzopyran) (median: 17.7 ng/g lw) was the dominant musk. There was no statistical correlation between total musk concentrations, and HCB, HCHs, DDTs or total OCP concentrations, indicating their different exposure routes and metabolism in humans (p=0.182-0.325). Clear reductions in temporal trends in the levels of DDTs and HCB, especially HCHs (p<0.01) were observed during the sampling period, and the high DDE/DDT ratios in the samples indicated past exposure to DDTs. The relatively high median concentrations of HHCB and HHCB-lactone in 2010 suggested a probably increasing tendency. There were statistically significant influences regarding maternal age and parity on OCP accumulation (p=0.001-0.002), but no significant effect on musks was found (p=0.542-0.919). Musk exposure in neonates via breast milk was 2-3 orders of magnitude lower than suggested provisional tolerable daily intakes (PTDI). The estimated daily intakes for HCB and DDTs were below the PTDI in Canada, however, 56% of those for HCHs exceeded the Canadian PTDI. OCP contamination of breast milk requires further attention.


Asunto(s)
Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Exposición Materna , Leche Humana/química , Plaguicidas/análisis , Adulto , China , Monitoreo del Ambiente , Contaminantes Ambientales/química , Femenino , Humanos , Hidrocarburos Clorados/química , Factores de Tiempo , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-36361152

RESUMEN

Octachlorostyrene (OCS) is a ubiquitous persistent organic pollutant; however, information regarding the toxicological effects of OCS remains limited. In this study, we studied the toxicity mechanisms of OCS using human liver carcinoma (HepG2) cells. The results showed that OCS reduced cell viability in a time- and dose-dependent manner. Compared with that in the control, the level of reactive oxygen species (ROS) was significantly increased in all treated HepG2 cells. We also found that (1) OCS induced damage in the HepG2 cells via the apoptotic signaling pathway, (2) OCS increased intracellular free Ca2+ concentration (>180%), and (3) following exposure to 80 µM OCS, there was an increase in mitochondrial transmembrane potential (MMP, ~174%), as well as a decrease in ATP levels (<78%). In conclusion, OCS is cytotoxic and can induce apoptosis, in which ROS and mitochondrial dysfunction play important roles; however, the observed increase in MMP appears to indicate that HepG2 is resistant to the toxicity induced by OCS.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Células Hep G2 , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial , Apoptosis
14.
Environ Technol ; 43(21): 3319-3328, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34129452

RESUMEN

A simple and low-cost route to fabricate sepiolite-supported bimetallic Fe/Ni (Sep-Fe/Ni) nanoparticles was obtained by synchronous liquid phase reduction method. The as prepared composite was used to remove triclosan (TCS) from aqueous solutions. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Brunauer-Emmett-Teller (BET) analysis were used for characterization of the materials. As the supporting material, Sep dispersed Fe/Ni nanoparticles on its surface effectively and reduced the agglomeration phenomenon, providing more reactive sites. Sep-Fe/Ni had a large surface area of 90.5 m2/g, which was considerably higher than that of Fe/Ni (9.2 m2/g). Sep-Fe/Ni exhibited an enhanced TCS removal efficiency, as compared to the Fe/Ni and Sep materials. Operation factors, including the solution pH, initial TCS concentration, and material dosage, were investigated and found to be influential for TCS removal. The kinetic analysis indicated that the depletion of TCS in aqueous solutions conformed to the pseudo-first-order kinetic model under optimized conditions. The transformation pathway of TCS was studied in detail, revealing that the dechlorination of TCS by Sep-Fe/Ni is a stepwise reaction, namely from TCS to di-chlorinated intermediates, with the newly formed intermediate products also degrading into mono-chlorinated products by further reductive dechlorination. This study demonstrated that Sep-Fe/Ni is a promising reductant for TCS removal in water.


Asunto(s)
Nanopartículas , Triclosán , Contaminantes Químicos del Agua , Hierro/química , Cinética , Silicatos de Magnesio , Nanopartículas/química , Agua , Contaminantes Químicos del Agua/química
15.
Transl Androl Urol ; 11(3): 348-357, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35402198

RESUMEN

Background: In tumors, the role of human antigen R (HuR) includes regulating tumor cell proliferation, differentiation, apoptosis, angiogenesis, and lymphangiogenesis. Previous studies have revealed that the expression of HuR can be detected in bladder cancer, and is related to the biological behavior of malignancy. Methods: T24 cells were transfected by HuR overexpression and HuR knockdown vectors, and divided into the control group, the overexpression-HuR group, and the cas9-HuR group. Cell viability was detected after 48 h by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, apoptosis was detected by Annexin V-allophycocyanin (APC)/7-aminoactinomycin D (7-AAD) double staining, cell migration was detected by Transwell assays, and the expression levels of HuR, cyclin D1, and apoptosis-related factors [i.e., B-cell lymphoma 2 (Bcl-2)] were detected by fluorescence quantitative polymerase chain reaction (PCR) and Western blot. Results: Compared to the control group, cell viability after 48 h increased significantly in the overexpression-HuR group, and decreased significantly in the cas9-HuR group (P<0.05). The number of migrating cells increased significantly in the overexpression-HuR group, and decreased significantly in the cas9-HuR group (P<0.05). The apoptosis rate was significantly decreased in the overexpression-HuR group, and significantly increased in the cas9-HuR group (P<0.05). The messenger ribonucleic acid and protein expression levels of HuR, cyclin D1, and Bcl-2 were significantly increased in the overexpression-HuR group, and significantly decreased in the cas9-HuR group (P<0.05). Conclusions: HuR promotes the proliferation and migration of T24 cells, and inhibits cell apoptosis. The mechanism may be related to the expression of cyclin D and the apoptosis-related protein, Bcl-2.

16.
Environ Sci Technol ; 45(7): 2619-25, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21401087

RESUMEN

Several studies have indicated that mixed brominated/chlorinated organic compounds could be formed during the thermal process such as the incineration of municipal solid waste and open burning of unregulated e-waste at recycling areas. In this study, air particles and soils from e-waste recycling areas, as well as outdoor and indoor air particles from urban Guangzhou, were collected and pooled for the identification of mixed chlorinated/brominated diphenyl ethers (PXDEs). Three monochloro-nonabromo diphenyl ethers (Cl-nonaBDEs), including 6'-Cl-BDE-206, 5'-Cl-BDE-207, and/or 4'-Cl-BDE-208, were first structurally identified in these air and soil samples. The identification was done by comparison of retention times in chromatograms of pure reference compounds and environmental samples, as well as by comparison with full-scan mass spectra data in electron capture negative ionization mode. Because of their similar physical-chemical properties, 4'-Cl-BDE-208 and 5'-Cl-BDE-207 absolutely coeluted, even on a nonpolar DB-5 column. Further investigation is still needed to clarify these findings. Nevertheless, the results indicated that Cl-nonaBDEs would occur in various environmental matrices. Because the replacement of Br by Cl will change the physical-chemical properties of PBDE analogues, environmental occurrence, fate, and transport, the potential toxicity of PXDEs should be investigated.


Asunto(s)
Contaminantes Atmosféricos/análisis , Éteres Difenilos Halogenados/análisis , Contaminantes del Suelo/análisis , Contaminantes Atmosféricos/química , Atmósfera/química , China , Monitoreo del Ambiente , Contaminación Ambiental/estadística & datos numéricos , Éteres Difenilos Halogenados/química , Suelo/química , Contaminantes del Suelo/química
17.
Oncol Lett ; 21(4): 305, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33732381

RESUMEN

The present study aimed to investigate the roles of Notch1 in the biological processes of bladder cancer cells (BCCs) in vitro. Short hairpin (sh)RNA targeting Notch1 was designed and constructed, and the T24 and 5637 BCCs were selected for transfection. The cells were classified into two groups: shRNA negative control (NC) and Notch1 shRNA. MTT and Transwell assays, and flow cytometry were performed to examine the changes in cell proliferation, invasiveness, and apoptosis, respectively. In addition, reverse transcription-quantitative PCR and western blot analysis was used to detect the mRNA and protein expression levels of apoptosis-related proteins (Bax, Bid and Bcl2) and epithelial-mesenchymal transition factors (vimentin and E- and N-cadherin). Compared with that in the shRNA NC group, the Notch1 shRNA group showed significantly decreased cell proliferation rate and invasiveness; increased apoptotic rate; elevated mRNA expression levels of Bad, Bid and E-cadherin; and reduced mRNA expression levels of Bcl2, N-cadherin and vimentin. The trends for protein expression levels were the same as those for mRNA levels. Notch1 silencing inhibited invasion and promoted apoptosis of BCCs.

18.
Int J Clin Exp Pathol ; 13(6): 1468-1473, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32661486

RESUMEN

Giant multilocular prostatic cystadenoma is a rare benign tumor that originates from the prostate gland. It usually is between the rectum and the bladder, and is composed of predominantly cystic enlarged prostatic glands in a fibrous stroma and spreads extensively in the pelvis. The mass usually causes a series of obstructive symptoms by compressing adjacent organs. Here we report a case of a giant multilocular prostatic cystadenoma in a 16-year-old patient, who is the youngest case reported up to now, complaining of difficulty in defecation.

19.
Chemosphere ; 249: 126215, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32088460

RESUMEN

Nonthermal plasma (NTP) degradation has been shown to be a promising method for volatile organic compounds (VOCs) removal from air. However, there have been few studies on the degradation of indoor VOCs using NTP, and even less on their reaction kinetics. In this study, NTP degradation of acetone, a representative of oxygenated VOCs, in a closed-loop reactor operating in recirculation mode was investigated. Acetone and organic by-products were characterized in real-time by proton transfer reaction time-of-flight mass spectrometry. The results showed that approximately 85.7% of the acetone degraded within 7.5 h with dielectric barrier discharge treatment at 4.3 W. Methanol, acetaldehyde, formic acid, and acetic acid were observed to be the main organic byproducts with concentrations time-dependent on the order of ppb/ppm. The concentrations of the inorganic by-products O3 and NO2 are also time-dependent and can decrease to nearly 0 after a sufficient degradation time. Based on the concentration measurement in real-time, several rate laws were used to fit the concentration variations of acetone and the organic by-products, and it was observed that they strictly followed the simple kinetic reaction rate laws: acetone followed the first-order rate law, and formic acid formation followed the one-half-order rate law, etc. This study provides a good example of characterizing NTP removal of VOCs in airtight spaces and has important theoretical and practical significance in designing a better NTP device, predicting NTP degradation reaction rate, and accelerating the practical application of NTP technology for indoor air treatment.


Asunto(s)
Acetona/química , Acetaldehído , Cinética , Estudios Longitudinales , Espectrometría de Masas/métodos , Metanol , Modelos Químicos , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química
20.
Am J Transl Res ; 12(5): 1515-1534, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32509159

RESUMEN

Graphene-family nanomaterials (GFNs) have been widely used in cancer therapy, tissue engineering, antibacterial and biological imaging due to their optical, thermal, and drug absorption properties. When used as drug and gene nanocarrier, the major limitations are aggregation, biocompatibility, and inappropriate release of drugs or genes. To overcome these problems, researchers have developed a variety of functionalization processes. In this review, we grouped the functionalization according to the decoration molecules, putting particular emphasis on the gene delivery. Organic and inorganic materials resulted as the major sets to introduce functional sections onto graphene oxide (GO). We also classified the target molecules used in the GO delivery system, as well as introduced other strategies to increase the delivery efficacy such as controlled release and magnetic targeting.

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