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1.
Artículo en Inglés | MEDLINE | ID: mdl-39231305

RESUMEN

Objective: This review aims to summarize existing interventions from the international literature addressing fertility concerns in cancer patients, providing theoretical and practical guidance for future interventions. Methods: In September 2023, a systematic search covering 13 databases was conducted using the methodology outlined by the Joanne Briggs Institute for a comprehensive systematic review. This search identified published English and Chinese-language papers. Results: A total of 20 studies meeting inclusion criteria were included in this review. The studies predominantly originated in China and the United States. A comprehensive synthesis of interventions from the included literature across three dimensions and seven aspects was conducted. The interventions primarily focused on psychological interventions and web-based self-help tools for patients. The Reproductive Concerns After Cancer Scale (RCAC) was the primary assessment tool employed. Conclusion: Addressing fertility concerns in cancer patients is a complex issue involving various stakeholders and diverse intervention strategies. Lessons from international research can inform the development of context-specific interventions tailored to individual needs.

2.
Front Microbiol ; 15: 1448265, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38983629

RESUMEN

[This corrects the article DOI: 10.3389/fmicb.2024.1406526.].

3.
Front Microbiol ; 15: 1406526, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38812681

RESUMEN

Objectives: The study aims to systematically identify the alterations in gut microbiota that observed in gastric cancer through comprehensive assessment of case-control studies. Methods: The systematic literature search of PubMed, Embase, Cochrane Library, and Web of Science was conducted to identify case-control studies that compared the microbiomes of individuals with and without gastric cancer. Quality of included studies was evaluated with the Newcastle-Ottawa Quality Assessment Scale (NOS). Meta-analyses utilized a random-effects model, and subgroup and sensitivity analyses were performed to assess study heterogeneity. All data analyses were performed using the "metan" package in Stata 17.0, and the results were described using log odds ratios (log ORs) with 95% confidence intervals (CIs). Results: A total of 33 studies involving 4,829 participants were eligible for analysis with 29 studies provided changes in α diversity and 18 studies reported ß diversity. Meta-analysis showed that only the Shannon index demonstrated statistical significance for α-diversity [-5.078 (-9.470, -0.686)]. No significant differences were observed at the phylum level, while 11 bacteria at genus-level were identified significant changed, e.g., increasing in Lactobacillus [5.474, (0.949, 9.999)] and Streptococcus [5.095, (0.293, 9.897)] and decreasing in Porphyromonas and Rothia with the same [-8.602, (-11.396, -5.808)]. Sensitivity analysis indicated that the changes of 9 bacterial genus were robust. Subgroup analyses on countries revealed an increasing abundance of Helicobacter and Streptococcus in Koreans with gastric cancer, whereas those with gastric cancer from Portugal had a reduced Neisseria. Regarding the sample sources, the study observed an increase in Lactobacillus and Bacteroides in the gastric mucosa of people with gastric cancer, alongside Helicobacter and Streptococcus. However, the relative abundance of Bacteroides decreased compared to the non-gastric cancer group, which was indicated in fecal samples. Conclusion: This study identified robust changes of 9 bacterial genus in people with gastric cancer, which were country-/sample source-specific. Large-scale studies are needed to explore the mechanisms underlying these changes. Systematic Review: Unique Identifier: CRD42023437426 https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023437426.

4.
Eur J Oncol Nurs ; 70: 102537, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38484619

RESUMEN

OBJECTIVE: This study aims to explore the intervention effects of narrative nursing on the reproductive concerns of cervical cancer patients of childbearing age undergoing surgical treatment. METHODS: Patients undergoing cervical cancer surgery with moderate to severe levels of reproductive concerns, treated between January and December 2023 at a tertiary Grade-A oncology hospital in China, were selected as the research subjects. Patients were randomized into an intervention group and a control group, each consisting of 33 patients. The control group received standard nursing care, while the intervention group received a narrative nursing intervention in addition to standard care. The changes in the levels of reproductive concerns, post-traumatic growth, and quality of life scores before and after the intervention were compared between the two groups. RESULTS: After the intervention, the reproductive concerns scores of the cervical cancer patients in the intervention group (32.53 ± 4.77) were significantly lower than those in the control group (59.29 ± 3.24), with a statistically significant difference (t = 26.143, p < 0.001). The post-traumatic growth scores in the intervention group (86.78 ± 3.52) were significantly higher than those in the control group (68.06 ± 6.24), with a statistically significant difference (t = -14.595, p < 0.001). The quality of life scores in the intervention group (149.00 [IQR = 8.75]) were significantly higher than those in the control group (129.00 [IQR = 13.00]), with a statistically significant difference (z = -5.799, p < 0.001). CONCLUSION: Narrative nursing can effectively alleviate reproductive concerns in cervical cancer patients undergoing surgical treatment, promote positive psychological changes post-trauma, and improve patients' quality of life.


Asunto(s)
Calidad de Vida , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/cirugía , Adulto , China , Persona de Mediana Edad , Terapia Narrativa/métodos
5.
Chemosphere ; 354: 141689, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492677

RESUMEN

Quantitative studies of nanoplastics (NPs) abundance on agricultural crops are crucial for understanding the environmental impact and potential health risks of NPs. However, the actual extent of NP contamination in different crops remains unclear, and therefore insufficient quantitative data are available for adequate exposure assessments. Herein, a method with nitric acid digestion, multiple organic extraction combined with pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) quantification was used to determine the chemical composition and mass concentration of NPs in different crops (cowpea, flowering cabbage, rutabagas, and chieh-qua). Recoveries of 74.2-109.3% were obtained for different NPs in standard products (N = 6, RSD <9.6%). The limit of detection (LOD) and the limit of quantitation (LOQ) were 0.02-0.5 µg and 0.06-1.5 µg, respectively. The detection method for NPs exhibited good external calibration curves and linearity with 0.99. The results showed that poly (vinylchloride) (PVC), poly (ethylene terephthalate) (PET), polyethylene (PE), and polyadiohexylenediamine (PA66) NPs could be detected in crop samples, although the accumulation levels associated with the various crops varied significantly. PVC (N.D.-954.3 mg kg-1, dry weight (DW)) and PE (101.3-462.9 mg kg-1, DW) NPs were the dominant components in the samples of all four crop species, while high levels of PET (414.3-1430.1 mg kg-1, DW) NPs were detected in cowpea samples. Furthermore, there were notable differences in the accumulation levels of various edible crop parts, such as stems (60.2%) > leaves (39.8%) in flowering cabbage samples and peas (58.8%) > pods (41.2%) in cowpea samples. This study revealed the actual extent of NP contamination in different types of crops and provided crucial reference data for future research.


Asunto(s)
Microplásticos , Pirólisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Límite de Detección , Productos Agrícolas
6.
Cancer Med ; 11(16): 3093-3105, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35297216

RESUMEN

INTRODUCTION: The main emphasis of the research about adjuvant imatinib for high-risk gastrointestinal stromal tumors (GISTs) is prolonging the treatment duration and ignores the heterogeneous that 10-year recurrence rates ranged from about 20%-100%. Thus, this study evaluated the effect of different durations of adjuvant imatinib on outcomes in high-risk GISTs to explore the feasibility of individual treatment. METHODS: We analyzed 855 high-risk GIST patients from three centers who underwent macroscopically complete resection between December 2007 and September 2020. The patients were divided into training (n =564) and two validation cohorts (n = 238 and53) based on their source. Recurrence-free survival (RFS) was the primary point. Cox multivariate analysis was used to develop the nomogram. C-index, time-dependent area under the curves, and calibration plots were used to assess the performance of the nomogram. RESULTS: Univariate analysis showed that longer adjuvant imatinib was significantly associated with better 5-year RFS (p < 0.0001). Further investigation identified that the same high-risk patients with lower tumor-associated recurrence risk benefitted little from prolonged treatment and that the recommended adjuvant imatinib duration was insufficient for those with higher recurrence risk. A nomogram for predicting 2-, 3-, and 5-year RFS based on different treatment durations and four major risk factors, namely, tumor site, size, mitotic count, and rupture status, was built and validated, with a C-index of 0.82, 0.74, and 0.70 in training and two external validation cohorts, respectively. An online dynamic nomogram was further developed for clinical applications (https://ruolinliu666.shinyapps.io/GIST/), offering predictive recurrence rates based on different treatment durations and tumor features. CONCLUSIONS: We developed a nomogram to predict the recurrence risk for high-risk patients according to tumor features and treatment durations of imatinib to help physicians on decision-making for individualized treatment duration.


Asunto(s)
Antineoplásicos , Tumores del Estroma Gastrointestinal , Adyuvantes Inmunológicos/uso terapéutico , Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante , Tumores del Estroma Gastrointestinal/patología , Humanos , Mesilato de Imatinib/uso terapéutico , Recurrencia Local de Neoplasia/patología , Nomogramas , Estudios Retrospectivos , Factores de Riesgo
7.
Toxins (Basel) ; 14(2)2022 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-35202147

RESUMEN

Pseudorabies, caused by pseudorabies virus (PRV), is the main highly infectious disease that severely affects the pig industry globally. T-2 toxin (T2), a significant mycotoxin, is widely spread in food and feeds and shows high toxicity to mammals. The potential mechanism of the interaction between viruses and toxins is of great research value because revealing this mechanism may provide new ideas for their joint prevention and control. In this study, we investigated the effect of T2 on PRV replication and the mechanism of action. The results showed that at a low dose (10 nM), T2 had no significant effect on porcine kidney 15 (PK15) cell viability. However, this T2 concentration alleviated PRV-induced cell injury and increased cell survival time. Additionally, the number of PK15 cells infected with PRV significantly reduced by T2 treatment. Similarly, T2 significantly decreased the copy number of PRV. Investigation of the mechanism revealed that 10 nM T2 significantly inhibits PRV replication and leads to downregulation of oxidative stress- and apoptosis-related genes. These results suggest that oxidative stress and apoptosis are involved in the inhibition of PRV replication in PK15 cells by low-concentration T2. Taken together, we demonstrated the protective effects of T2 against PRV infection. A low T2 concentration inhibited the replication of PRV in PK15 cells, and this process was accompanied by downregulation of the oxidative stress and apoptosis signaling pathways. Our findings partly explain the interaction mechanism between T2 and PRV, relating to oxidative stress and apoptosis, though further research is required.


Asunto(s)
Células Epiteliales/efectos de los fármacos , Herpesvirus Suido 1/efectos de los fármacos , Toxina T-2/farmacología , Replicación Viral/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Células Epiteliales/virología , Herpesvirus Suido 1/fisiología , Riñón/citología , Estrés Oxidativo/efectos de los fármacos , Porcinos
8.
Ann Clin Lab Sci ; 51(4): 494-502, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34452887

RESUMEN

OBJECTIVE: Gastric cancer is one of the most common gastrointestinal malignancies. miRNAs (microRNAs) have been reported to play a pivotal role in the tumorigenesis of gastric cancer. However, the role of miR-643 in gastric cancer is not fully understood. METHODS: The expression of miR-643 in gastric cancer cell lines was detected by qRT-PCR (quantitative reverse transcription PCR). Cell viability, apoptosis, migration, and invasion were assessed using the Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, and wound scratch and Transwell assays, respectively. The target gene of miR-643 was predicted by bioinformatics analysis and validated using luciferase reporter assay. RESULTS: The expression level of miR-643 in gastric cancer cell lines was lower than in the normal gastric epithelium cell line (GES-1). Overexpression of miR-643 inhibited cell viability and colony formation but promoted cell apoptosis in gastric cancer. Transwell invasion assay and in vitro scratch assay evidenced that miR-643 overexpression inhibited gastric cancer cell migration and invasion. Bioinformatics analysis revealed that miR-643 could directly target TXNDC9 (Thioredoxin domain containing 9), and luciferase reporter assay validated this result. Further analysis showed that miR-643 mimics caused a significant reduction of TXNDC9 in gastric cancer cells. Moreover, TXNDC9 overexpression reversed the effects of miR-643 mimics on gastric cancer cell viability, invasion, and migration. CONCLUSION: miR-643 functions as a potential tumor suppressor in gastric cancer by inhibiting cell viability, colony formation, migration, and invasion via targeting TXNDC9, which provides a novel target for the diagnostic treatment of gastric cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Gástricas/patología , Tiorredoxinas/metabolismo , Apoptosis , Biomarcadores de Tumor/genética , Transición Epitelial-Mesenquimal , Humanos , Invasividad Neoplásica , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Tiorredoxinas/genética , Células Tumorales Cultivadas
9.
Aging (Albany NY) ; 13(13): 17734-17767, 2021 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-34247148

RESUMEN

Limited progress has been made in the treatment of gastric adenocarcinoma (GAC) in recent years, but the potential of immunotherapy in GAC is worthy of consideration. The purpose of this study was to develop a reliable, personalized signature based on immune genes to predict the prognosis of GAC. Here, we identified two groups of patients with significantly different prognoses by performing unsupervised clustering analysis of The Cancer Genome Atlas (TCGA) database based on 881 immune genes. The immune signature was constructed with a training set composed of 350 GAC samples from the TCGA and subsequently validated with 431 samples from GSE84437, 432 samples from GSE26253, and 145 GAC samples from real-time quantitative reverse transcription polymerase chain reaction data. This classification system can also be used to predict prognosis in different clinical subgroups. Further analysis suggested that high-risk patients were characterized by low immune scores, distinctive immune cell proportions, different immune checkpoint profiles, and a low tumor mutational burden. Ultimately, the signature was identified as an independent prognostic factor. In general, the signature can accurately predict recurrence and overall survival in patients with GAC and may serve as a powerful prognostic tool to further optimize cancer immunotherapy.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/inmunología , Inmunidad/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/inmunología , Adulto , Anciano , Biomarcadores de Tumor/análisis , Análisis por Conglomerados , Biología Computacional , Bases de Datos Genéticas , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunoterapia , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Reacción en Cadena de la Polimerasa , Medicina de Precisión , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Supervivencia
10.
Aging (Albany NY) ; 13(11): 15548-15568, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34106877

RESUMEN

Childhood acute lymphoblastic leukemia (cALL) still represents a major cause of disease-related death in children. This study aimed to explore the prognostic value of long non-coding RNAs (lncRNAs) in cALL. We downloaded lncRNA expression profiles from the TARGET and GEO databases. Univariate, least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analyses were applied to identify lncRNA-based signatures. We identified an eight-lncRNA signature (LINC00630, HDAC2-AS2, LINC01278, AL356599.1, AC114490.1, AL132639.3, FUT8.AS1, and TTC28.AS1), which separated the patients into two groups with significantly different overall survival rates. A nomogram based on the signature, BCR ABL1 status and white blood cell count at diagnosis was developed and showed good accuracy for predicting the 3-, 5- and 7-year survival probability of cALL patients. The C-index values of the nomogram in the training and internal validation set reached 0.8 (95% CI, 0.757 to 0.843) and 0.806 (95% CI, 0.728 to 0.884), respectively. The nomogram proposed in this study objectively and accurately predicted the prognosis of cALL. In vitro experiments suggested that LINC01278 promoted the proliferation of leukemic cells and inhibited leukemic cell apoptosis by targeting the inhibition of miR-500b-3p in cALL, and LINC01278 may be a biological target for the treatment of cALL in the future.


Asunto(s)
Biomarcadores de Tumor/genética , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Nomogramas , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , ARN Largo no Codificante/genética , Adulto , Apoptosis/genética , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Niño , Bases de Datos Genéticas , Femenino , Redes Reguladoras de Genes , Humanos , Masculino , Anotación de Secuencia Molecular , Análisis Multivariante , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Análisis de Supervivencia
12.
Ecotoxicol Environ Saf ; 208: 111420, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33080421

RESUMEN

Cadmium (Cd) contamination in soil-rice systems has become a global public concern. However, influencing factors and the contamination threshold of Cd in soils remain largely unknown owing to soil heterogeneity, which limits our ability to assess the risk to human health and to draft appropriate environmental policies. In this study, we selected the soil-rice system of Longtang and Shijiao town in southern China, which was characterized by multi-metal acidic soil contamination due to improper electronic waste recycling activities, as a case to analyze the influence of different soil properties on the Cd threshold in the soil and Cd accumulation in rice. The results showed that soil organic matter (SOM) was the main factor regulating Cd accumulation in the soil-rice system. Moreover, compared with the total Cd concentration, the DTPA-extractable Cd concentration in the soil was a better predictor of Cd transportation in the soil-rice system. According to the prediction model, when SOM was < 35 g kg-1, the CdDTPA threshold was 0.16 mg kg-1 with a 95% likelihood of Cdrice accumulation above the Chinese food standard limit (0.2 mg kg-1). Conversely, when SOM was ≥ 35 g kg-1, the CdDTPA threshold was only 0.03 mg kg-1. This study of the influence of SOM on Cd accumulation in a soil-rice system confirms that SOM is a crucial parameter for better and safer rice production, especially in multi-metal contaminated acidic soils.


Asunto(s)
Cadmio/análisis , Modelos Químicos , Contaminantes del Suelo/análisis , Ácidos , China , Contaminación Ambiental , Humanos , Oryza/efectos de los fármacos , Suelo
13.
J Hazard Mater ; 377: 321-329, 2019 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-31173982

RESUMEN

This study developed a cost-effective and eco-friendly method by coupling plant extracts (take green tea for example) and Fe(III) to reduce Cr(VI) and precipitate Cr(III). At acidic pH, 1.43 mM Fe(III) combined with 1.33 g/L green tea extracts could reduce 93% of Cr(VI) in 180 min, which was much larger than ˜50% by green tea extracts alone. Moreover, 52% of Cr(III) could automatically precipitate out as mixed Fe(III)-Cr(III) (oxy)-hydroxide solids. In the viewpoint of mechanism, polyphenols in green tea extracts were the reactive constituents and transformed Fe(III) to Fe(II), by which step the aqueous Fe(II) level was maintained to continuously reduce Cr(VI) to Cr(III), and thus accelerating Cr(VI) reduction. The generated Fe(III) partially participated in the reaction with polyphenols again and some Fe(III) formed precipitates with Cr(III). Overall, the electron transfers in the polyphenol-Fe-Cr cyclic reactions made Fe(III) used for multiple times, thus accelerated Cr(VI) reduction. The applicability of the combined process was further verified by removing 100% and 70% of Cr(VI) from electroplating wastewater and contaminated soil, respectively. As polyphenols can be derived from plant wastes and Fe(III) is naturally abundant, this study provides a promising method for in situ remediation of Cr(VI)-contaminated sites.

14.
Gene ; 681: 62-68, 2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30267809

RESUMEN

Homeobox A5 (HOXA5) is a member of the HOX protein family which were implicated in serval critical process and was cancer-specific dysregulated in human cancers. However, its expression and function in human gastric cancer (GC) was still largely unknown. In this study, we confirmed for the first time that HOXA5 mRNA and protein was down-regulated in GC tissues and cell lines. Clinical data showed that low HOXA5 was significantly associated poor prognostic features, including large tumor size and advanced TNM stage. For 5-year survival, HOXA5 served as a potential prognostic marker of GC patients. Notably, HOXA5 inhibited cell viability, colony formation, proliferation, cell cycle progression and promoted apoptosis in vitro and in vivo. Furthermore, we demonstrated that HOXA5 expression was regulated by miR-196a. In GC tissues, miR-196a has an inverse correlation with HOXA5 expression. Conclusively, our results demonstrated that HOXA5 functions as a tumor suppressor in regulating tumor growth of GC under regulation of miR-196a, supporting its potential utility as a therapeutic target for GC.


Asunto(s)
Proliferación Celular/genética , Proteínas de Homeodominio/fisiología , MicroARNs/fisiología , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Biomarcadores de Tumor/genética , Células Cultivadas , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Xenoinjertos , Proteínas de Homeodominio/genética , Humanos , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia
15.
Chemosphere ; 212: 845-852, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30193233

RESUMEN

Surfactants are used to assist the zero-valent iron-mediated reductive dechlorination (ZVI-RD) of hydrophobic organic contaminants (HOCs). Although the effect of surfactants has been investigated in single-factor systems, the relationships between the surfactant and the matrix properties during RD are not well understood. Thus, an orthogonal experiment and post-experiment characterization of ZVI were conducted in the present study to estimate the integrated effects of plausible factors. The results showed that the introduction of surfactants significantly influenced the reduction of 2,2',5,5'-tetrachlorinated biphenyl (PCB-52) by altering the contact between ZVI and PCB-52. An anionic surfactant was able to alleviate the adverse impact of high amounts of non-ionic surfactants and humic acid (used as representative soil organic matter) by changing their sorption behaviors, which were also influenced by the initial pH value. However, the reduction of ZVI by humic acid decreased the electron transfer efficiency of ZVI, and also reduced the contact between ZVI and PCB-52 by generating FeCO3. These results suggest that the rate-limiting process for the ZVI-RD of HOCs in the soil/sediment solution is the contact between ZVI and HOCs, which can be improved by the addition of surfactants at concentrations corresponding to the maximum adsorption capacity of HOCs on the ZVI surface.


Asunto(s)
Halogenación , Bifenilos Policlorados/química , Tensoactivos/química , Adsorción , Hierro/química , Compuestos Orgánicos , Suelo/química
16.
Chemosphere ; 189: 479-488, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28957765

RESUMEN

Dredging and disposal is commonly used for cleanup of contaminated sediments, leaving the relocated sediments still in need of remediation. In this study, the feasibility of two approaches to using zerovalent iron (ZVI) in conjunction with surfactants to remediate sediments contaminated by polychlorinated biphenyls (PCBs) and Ni was investigated. Approach A is surfactant desorption followed by ZVI treatment and approach B is a simple mixture of ZVI and sediment in surfactant solution. Results of approach A show that 65.24% of PCBs and 2.12% of Ni were desorbed by 1% Envirosurf; however, the sequential ZVI-mediated reductive dechlorination (ZVI-RD) was ineffective due to micelle sequestration by high contents of surfactants while Ni could be almost completely removed. For approach B, less than 1% of coexisting Ni was released to aqueous solution, and 47.18%-76.31% PCBs could be dechlorinated by ZVI with the addition of 0.04% surfactants (Tween-80 and Envirosurf). Results of dechlorination kinetics and ZVI morphologies reveal that surfactants at the concentrations as low as 0.04% were able to enhance the contact of sediment-bound PCBs with ZVI, and also to alleviate ZVI passivation. The PCB mixtures in sediment were continuously desorbed and dechlorinated, yielding lower substituted homologues that are less toxic and less hydrophobic. Thus, a simple mixture of ZVI and contaminated sediments without dewatering appears to be a promising alternative to the remediation of PCBs-contaminated sediments.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Sedimentos Geológicos/química , Níquel/análisis , Bifenilos Policlorados/análisis , Halogenación , Hierro/química , Bifenilos Policlorados/química , Tensoactivos , Agua
17.
Environ Sci Pollut Res Int ; 22(1): 555-64, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25087495

RESUMEN

Effective dehalogenation by nanoscale zerovalent iron (nZVI) has been reported. In this study, the effects of Ni(2+), Cu(2+) ions, and the nonionic surfactant Tween-80 on dechlorination of 2,2',5,5'-tetrachlorinated biphenyl (PCB-52) by nZVI were investigated in aqueous solution. The rate of dechlorination was significantly enhanced by Ni(2+), while Cu(2+) had a less significant catalytic effect. Ni(2+) and Tween-80 used in combination synergistically enhanced dechlorination of PCB-52 by nZVI, although the enhancement by Tween-80 was inhibitory in the presence of Cu(2+) and insignificant in the absence of both metal ions. Congener specificity in the dechlorination pathway resulted from the preferential retention of ortho-chlorine, which restricted the formation of environmentally toxic coplanar PCB congeners. The application of nZVI dehalogenation enhanced by Ni(2+) and Tween-80 is a promising technique for posttreatment of PCB-contaminated soil washing solutions.


Asunto(s)
Bifenilos Policlorados/química , Contaminantes del Suelo/química , Compuestos de Bifenilo , Cloro , Contaminación Ambiental , Halogenación , Hierro , Metales , Níquel/química , Polisorbatos/química , Polisorbatos/metabolismo , Tensoactivos
18.
Ecotoxicol Environ Saf ; 90: 21-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23312040

RESUMEN

The effects of decabromodiphenyl ether (BDE-209) on avoidance response, survival, growth, and reproduction of earthworms (Eisenia fetida) were investigated under laboratory conditions using natural and artificial soils as substrate. Results showed that no significant avoidance response was observed when earthworms were exposed to 0.1-1000 mg/kg of BDE-209 for 48 h. After 28-days exposure, no significant effects on survival and growth of adult earthworms was induced by 0.1-1000 mg/kg of BDE-209 indicating the Lowest Observed Effect Level (LOEL) of BDE-209 on their survival and body weight was more than 1000 mg/kg. Except for a significant decrease in the number of juveniles per hatched cocoon in artificial soils at 1000 mg/kg of BDE-209, no significant effects on reproductive parameters (e.g. cocoon production per earthworms, weight per cocoon and cocoon hatchability) were observed. These results suggest that adult earthworms have a strong tolerance for BDE-209 exposure in soils, but a potential toxicity does exist for earthworm embryos or juveniles.


Asunto(s)
Éteres Difenilos Halogenados/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Conducta Animal/efectos de los fármacos , Éteres Difenilos Halogenados/análisis , Oligoquetos/crecimiento & desarrollo , Oligoquetos/fisiología , Reproducción/efectos de los fármacos , Suelo/química , Contaminantes del Suelo/análisis , Análisis de Supervivencia
19.
Ecotoxicology ; 20(5): 993-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21424720

RESUMEN

Antioxidant responses induced by decabromodiphenyl ether (BDE-209) in the earthworms (Eisenia fetida) were studied after 7 days of exposure. Electron paramagnetic resonance (EPR) spectra indicated that hydroxyl radicals (•OH) in earthworms were significantly induced by 0.01-10 mg/kg of BDE-209. Malondialdehyde (MDA) and protein carbonyl (PCO) were stimulated at 0.5-10 mg/kg and 1-10 mg/kg, respectively. The reduced glutathione (GSH) was inhibited at 1-10 mg/kg while oxidized glutathione (GSSG) accumulated at 0.5-10 mg/kg. The GSH/GSSG ratio decreased at 0.5-10 mg/kg, and superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were induced at 0.1-1 and 0.5 mg/kg, respectively and both decreased at 10 mg/kg. Catalase (CAT) activities increased at 1-10 mg/kg. The results showed that severe oxidative stress occurred in E. fetida, and may play an important role in inducing the toxicity of BDE-209 on earthworms.


Asunto(s)
Éteres Difenilos Halogenados/toxicidad , Radical Hidroxilo/metabolismo , Oligoquetos/efectos de los fármacos , Estrés Oxidativo , Contaminantes del Suelo/toxicidad , Animales , Catalasa/metabolismo , Glutatión/metabolismo , Disulfuro de Glutatión/metabolismo , Glutatión Transferasa/metabolismo , Malondialdehído/metabolismo , Oligoquetos/metabolismo , Superóxido Dismutasa/metabolismo
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