Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 91
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; : e2312209, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530091

RESUMEN

Developing novel proton exchange membranes (PEMs) with low cost and superior performance to replace Nafion is of great significance. Polyoxometalate-doped sulfonated poly(aryl ether ketone sulfone) (SPAEKS) allows for the amalgamation of the advantages in each constituent, thereby achieving an optimized performance for the hybrid PEMs. Herein, the hybrid membranes by introducing 2MeIm-{Mo132} into SPAEKS are obtained. Excellent hydrophilic properties of 2MeIm-{Mo132} can help more water molecules be retained in the hybrid membrane, providing abundant carriers for proton transport and proton hopping sites to build successive hydrophilic channels, thus lowering the energy barrier, accelerating the proton migration, and significantly fostering the proton conductivity of hybrid membranes. Especially, SP-2MIMo132-5 exhibits an enhanced proton conductivity of 75 mS cm-1 at 80 °C, which is 82.9% higher than pristine SPAEKS membrane. Additionally, this membrane is suitable for application in proton exchange membrane fuel cells, and a maximum power density of 266.2 mW cm-2 can be achieved at 80 °C, which far exceeds that of pristine SPAEKS membrane (54.6 mW cm-2). This work demonstrates that polyoxometalate-based clusters can serve as excellent proton conduction sites, opening up the choice of proton conduction carriers in hybrid membrane design and providing a novel idea to manufacture high-performance PEMs.

2.
Hum Genet ; 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37758909

RESUMEN

Nonmutational epigenetic reprogramming is a crucial mechanism contributing to the pronounced heterogeneity of prostate cancer (PCa). Among these mechanisms, N6-methyladenosine (m6A)-modified long non-coding RNAs (lncRNAs) have emerged as key players. However, the precise roles of m6A-modified lncRNAs in PCa remain to be elucidated. In this study, methylated RNA immunoprecipitation sequencing (MeRIP-seq) was conducted on primary and metastatic PCa samples, leading to the identification of 21 lncRNAs exhibiting differential methylation and expression patterns. We further established a PCa prognostic signature, named m6A-modified lncRNA score (mLs), based on 9 differential methylated lncRNAs in 4 multicenter cohorts. The high mLs score cohort exhibited a tendency for earlier biochemical recurrence (BCR) compared to the low mLs score cohort. Remarkably, the predictive performance of the mLs score surpassed that of five previously reported lncRNA-based signatures. Functional enrichment analysis underscored a negative correlation between the mLs score and lipid metabolism. Additionally, through MeRIP-qPCR, we pinpointed a hub gene, MIR210HG, which was validated through in vitro and in vivo experiments. These findings collectively illuminate the landscape of m6A-methylated lncRNAs in PCa tissue via MeRIP-seq and harness this information to prognosticate PCa outcomes using the mLs score. Furthermore, our study validates, both experimentally and mechanistically, the facilitative role of MIR210HG in driving PCa progression.

3.
J Cell Physiol ; 236(2): 1094-1104, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32657438

RESUMEN

Sox4 participates in the progression of embryo development and regulation of apoptosis in tumors. However, the effect and mechanism of Sox4 in myocardial infarction (MI) remains unclear. Therefore, we aimed at examining the role and molecular mechanism of Sox4 in the process of cardiomyocytes apoptosis during MI. The expression of Sox4 were obviously increased both in MI mice and in neonatal mouse cardiomyocytes treated with H2 O2 . Overexpression of Sox4 promoted cardiomyocyte apoptosis with or without H2 O2 , whereas knocking down of Sox4 alleviated H2 O2 -induced apoptosis in cardiomyocytes. Furthermore, silencing Sox4 by AAV-9 carried short hairpin RNA targeting Sox4 (AAV-9-sh-Sox4) markedly decreased cardiac infarct area, imprfoved cardiac dysfunction, and reversed apoptosis in MI mice. Mechanistically, there is a potential Sox4-binding site in the promoter region of Bim, and forced expression of Sox4 significantly promoted Bim expression in cultured cardiomyocytes with or without H2 O2 , whereas knocking down of Sox4 inhibited the expression of Bim. Further studies showed that silencing Bim attenuated Sox4-induced apoptosis in cardiomyocytes, indicating that Sox4 promoted cardiomyocytes apoptosis through regulation of Bim expression, which can be used as a potential therapeutic target for MI.


Asunto(s)
Proteína 11 Similar a Bcl2/genética , Infarto del Miocardio/genética , Isquemia Miocárdica/genética , Factores de Transcripción SOXC/genética , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Regulación de la Expresión Génica/genética , Humanos , Peróxido de Hidrógeno/farmacología , Ratones , Infarto del Miocardio/patología , Isquemia Miocárdica/patología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Regiones Promotoras Genéticas/genética
4.
Arch Microbiol ; 203(10): 5921-5930, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34586467

RESUMEN

Understanding the salt tolerance of microbial communities may help to elucidate the effects of salt concentration and other environmental factors on soil biodiversity. Here, high-throughput sequencing of 16S rDNA and ITS was combined to investigate the distribution and salt tolerance of microbial communities in coastal soils and sediments near the Yinggehai saltern field of Hainan Island, China. The microbial communities in the soils and sediments of the land zone (YGHLS), the intertidal zone (YGHIS), and the inshore zone (YGHWS) were compared. PCoA of weighted and unweighted UniFrac distance revealed obvious differences in soil microbial community among different samples. ANOSIM analysis could clearly separate the three samples from each other. Three halotolerant bacteria, including Halomonas, Halobacillus and Wallemia, were found in the samples, which accounted for 0.0335 ± 0.0586%, 0.0241 ± 0.0304%, and 0.0308 ± 0.0445% of the total microbial community, respectively. The relative abundance of Trk system potassium uptake protein, Kdp operon response regulator, and Na+/H+ antiporter in the samples exceeded 0.09%, 0.06%, and 0.02%, respectively, indicating that the Trk system plays a major role in the salt tolerance of halotolerant bacteria in Yinggehai coastal soils and sediments.


Asunto(s)
Microbiología del Suelo , Suelo , Bacterias/genética , Biodiversidad , China , Sedimentos Geológicos , ARN Ribosómico 16S/genética , Tolerancia a la Sal
5.
Arch Microbiol ; 203(5): 2453-2461, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33666689

RESUMEN

Characterization of microbial communities is important for understanding the soil biodiversity distribution affected by environmental factors. Here, we combined high-throughput sequencing of 16S rDNA and ITS to investigate the composition of bacterial and fungal communities in interval seawater covering Linchang Island, China. We compared the microbial communities in the soil of three sample points from the southern part to the northern part. No difference was observed in microbial abundance, richness and diversity in those three different locations. In addition, weighted and unweighted UniFrac distances revealed that three soil samples could not be separated from each other, even if the LCNS sample had significantly lower organic matter (OM), sodium and sulfate contents than the LCSS and LCMS samples. This result indicated that the microbial community of the soil may be influenced more strongly by interval seawater than by soil chemical characteristics. The bacterial phyla Proteobacteria, Actinobacteria, Acidobacteria, and Bacteroidetes were the four most abundant phyla in all samples, accounting for 83.22% of the microbial community. Escherichia-Shigella and Vibrio were abundant in the samples and accounted for 1.17% and 0.27%, respectively. Fungal structure, phylogenetic diversity, richness, and bacterial structure had a significant negative relationship with Vibrio abundance. In addition, Vibrio showed negative correlations with the genera Simiduia, Microbulbifer and Haliangium. The results reveal that the re-shaped microbiome and introduced typical microbes could be strategies for inhibiting Vibrio in the soil of Linchang Island.


Asunto(s)
Islas , Microbiota , Agua de Mar , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodiversidad , China , Microbiota/genética , Micobioma , Filogenia , ARN Ribosómico 16S/genética , Suelo/química
6.
Sensors (Basel) ; 21(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807719

RESUMEN

In order to remove the strong noise with complex shapes and high density in nuclear radiation scenes, a lightweight network composed of a Noise Learning Unit (NLU) and Texture Learning Unit (TLU) was designed. The NLU is bilinearly composed of a Multi-scale Kernel Module (MKM) and a Residual Module (RM), which learn non-local information and high-level features, respectively. Both the MKM and RM have receptive field blocks and attention blocks to enlarge receptive fields and enhance features. The TLU is at the bottom of the NLU and learns textures through an independent loss. The entire network adopts a Mish activation function and asymmetric convolutions to improve the overall performance. Compared with 12 denoising methods on our nuclear radiation dataset, the proposed method has the fewest model parameters, the highest quantitative metrics, and the best perceptual satisfaction, indicating its high denoising efficiency and rich texture retention.

7.
Curr Microbiol ; 77(7): 1292-1300, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32140834

RESUMEN

Characterizing soil bacterial community is important to understand microbial distribution affected by environmental factors. Here, we investigated the bacterial communities distributed from different location on Nanshazhou island, South China Sea. We collected and compared soil bacterial communities from central island, intertidal island, and inshore island. Results showed no difference in the bacterial richness and diversity for the soils from the three different locations. However, weighted and unweighted UniFrac distances analysis revealed that the three soil samples were clearly separated from each other. Five bacterial phyla, including Proteobacteria, Bacteroidetes, Verrucomicrobia, Spirochaetes and Tenericutes were more abundant in the inshore island sample; while Deinococcus-Thermus was more abundant in the intertidal island sample; and the central island sample had more abundant Gemmatimonadetes and Planctomycetes. Bacterial structure showed significantly positive relationships with organic matter content, but it was significantly negatively correlated with sodium content. Furthermore, a network analysis based on Spearman correlation coefficients showed that there were similar numbers of positive and negative correlations within the bacterial community of Nanshazhou island. Our results revealed that the soil bacterial communities in the three sampling sites were easily affected by environmental fluctuations.


Asunto(s)
Bacterias , Microbiota/genética , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Biodiversidad , China , Islas , Océanos y Mares
8.
Int J Mol Sci ; 20(24)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842349

RESUMEN

Palmitic acid, the most common saturated free fatty acid, can lead to lipotoxicity and apoptosis when overloaded in non-fat cells. Palmitic acid accumulation can induce pancreatic ß-cell dysfunction and cardiac myocyte apoptosis. Under various cellular stresses, the activation of p53 signaling can lead to cell cycle arrest, DNA repair, senescence, or apoptosis, depending on the severity/type of stress. Nonetheless, the precise role of p53 in lipotoxicity induced by palmitic acid is not clear. Here, our results show that palmitic acid induces p53 activation in a dose- and time-dependent manner. Furthermore, loss of p53 makes cells sensitive to palmitic acid-induced apoptosis. These results were demonstrated in human colon carcinoma cells (HCT116) and primary mouse embryo fibroblasts (MEF) through analysis of DNA fragmentation, flow cytometry, colony formation, and Western blots. In the HCT116 p53-/- cell line, palmitic acid induced greater reactive oxygen species formation compared to the p53+/+ cell line. The reactive oxygen species (ROS) scavengers N-acetyl cysteine (NAC) and reduced glutathione (GSH) partially attenuated apoptosis in the HCT116 p53-/- cell line but had no obvious effect on the p53+/+ cell line. Furthermore, p53 induced the expression of its downstream target genes, p21 and Sesn2, in response to ROS induced by palmitic acid. Loss of p21 also leads to more palmitic acid-induced cell apoptosis in the HCT116 cell line compared with HCT116 p53+/+ and HCT116 p53-/-. In a mouse model of obesity, glucose tolerance test assays showed higher glucose levels in p53-/- mice that received a high fat diet compared to wild type mice that received the same diet. There were no obvious differences between p53-/- and p53+/+ mice that received a regular diet. We conclude that p53 may provide some protection against palmitic acid- induced apoptosis in cells by targeting its downstream genes in response to this stress.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/genética , Resistencia a Medicamentos/genética , Ácido Palmítico/farmacología , Especies Reactivas de Oxígeno/metabolismo , Proteína p53 Supresora de Tumor/deficiencia , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Fibroblastos , Eliminación de Gen , Células HCT116 , Humanos , Ratones
9.
Int J Mol Sci ; 18(3)2017 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-28257089

RESUMEN

The gradual emerging of resistance to imatinib urgently calls for the development of new therapy for chronic myeloid leukemia (CML). The fusion protein Bcr-Abl, which promotes the malignant transformation of CML cells, is mainly located in the cytoplasm, while the c-Abl protein which is expressed in the nucleus can induce apoptosis. Based on the hetero-dimerization of FKBP (the 12-kDa FK506- and rapamycin-binding protein) and FRB (the FKBP-rapamycin binding domain of the protein kinase, mTOR) mediated by AP21967, we constructed a nuclear transport system to induce cytoplasmic Bcr-Abl into nuclear. In this study, we reported the construction of the nuclear transport system, and we demonstrated that FN3R (three nuclear localization signals were fused to FRBT2098L with a FLAG tag), HF2S (two FKBP domains were in tandem and fused to the SH2 domain of Grb2 with an HA tag) and Bcr-Abl form a complexus upon AP21967. Bcr-Abl was imported into the nucleus successfully by the nuclear transport system. The nuclear transport system inhibited CML cell proliferation through mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 5 (STAT5) pathways mainly by HF2S. It was proven that nuclear located Bcr-Abl induced CML cell (including imatinib-resistant K562G01 cells) apoptosis by activation of p73 and its downstream molecules. In summary, our study provides a new targeted therapy for the CML patients even with Tyrosine Kinase Inhibitor (TKI)-resistance.


Asunto(s)
Núcleo Celular/metabolismo , Proteínas de Fusión bcr-abl/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Señales de Localización Nuclear/farmacología , Tirosina/antagonistas & inhibidores , Apoptosis , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Proteínas de Fusión bcr-abl/química , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Factor de Transcripción STAT5/metabolismo , Sirolimus/análogos & derivados , Sirolimus/farmacología
10.
Tumour Biol ; 36(3): 1983-91, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25394900

RESUMEN

We previously demonstrated that microRNA (miR)-224 expression was significantly reduced in human prostate cancer (PCa) tissues and predicted unfavorable prognosis in patients. However, the underlying mechanisms of miR-224 have not been fully elucidated. In this study, calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) was identified as a target gene of miR-224. Then, we found that enforced expression of miR-224 could suppress PCa cell proliferation and cell cycle by regulating the expression of CAMKK2 in vitro. In addition, the expression levels of miR-224 in PCa tissues were negatively correlated with those of CAMKK2 mRNA significantly (Spearman's correlation: r = -0.66, P = 0.004). Moreover, combined low miR-224 expression and high CAMKK2 expression (miR-224-low/CAMKK2-high) was closely correlated with advanced clinical stage (P = 0.028). Furthermore, PCa patients with miR-224-low/CAMKK2-high expression more frequently had shorter overall survival than those in groups with other expression patterns of two molecules. In conclusion, our data offer the convincing evidence that miR-224 and its target gene CAMKK2 may synergistically contribute to the malignant progression of PCa. Combined detection of miR-224 and CAMKK2 expressions represents an efficient predictor of patient prognosis and may be a novel marker which can provide additional prognostic information in PCa.


Asunto(s)
Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/genética , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/patología , ARN Mensajero/genética
11.
BMC Urol ; 15: 90, 2015 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-26320076

RESUMEN

BACKGROUND: The NIMA-related kinase 2 (NEK2) is a serine/threonine kinase that is involved in regulation of centrosome duplication and spindle assembly during mitosis. Dysregulation of these processes causes chromosome instability and aneuploidy, which are hallmark changes of many solid tumors. However, whether aberrant expression of NEK2 is associated with outcome of prostate cancer (PCa) patients remains to be determined. METHODS: Expression of NEK2 in human PCa cells and primary PCa tissues was assessed by quantitative RT-PCR. Expression of NEK2 in human PCa cells was depleted with siRNA. Effects of the depletion on cell proliferation, survival, and tumorigenicity were assessed both in vitro with cell cultures and in vivo with subcutaneous implantation of xenografts. In silico analyses of the online Taylor dataset were carried out to determine whether the expression level of NEK2 correlated with the clinicopathological characteristics of prostate cancer. RESULTS: Compared with benign human prostatic epithelial cells and tissues, the expression of NEK2 was elevated in human PCa cells and primary PCa tissues. Depleting NEK2 expression inhibited human PCa cell proliferation in vitro and xenograft growth in vivo. Expression level of NEK2 in PCa positively correlated with the Gleason score and pathologic stage of the patient. CONCLUSION: The results suggest that overexpression of NEK2 has the potential to serve as a biomarker for PCa prognosis. Further validation with large sample pool is warrant.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Anciano , Animales , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Desnudos , Quinasas Relacionadas con NIMA , Pronóstico , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Sensibilidad y Especificidad , Regulación hacia Arriba
12.
Ecotoxicology ; 24(10): 2207-12, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26403610

RESUMEN

The surface interaction between heavy metals and natural organic matters (NOM) substantially affects their migration and conversion in natural environments. In this study, the chemical speciation and element mapping of Fe and Mn in reduced NOM were investigated. The results show that quinone and semiquinone moieties dominated the redox properties in NOM, and the EPR signal intensity exhibited pH dependence with an increase of EPR signal intensity at a higher pH value. The EPR results indicate that the complexes displayed the characteristics of superparamagnetic oxides/oxyhydroxides after Fe/Mn complexed with NOM. µ-XRF results suggest that the scatterplots of Fe and Mn distributions at pH 11 had the most positive linearly-related plot points, indicating strong correlations for Mn-Fe binary metallic ions. µ-XANES results further interpret the presence of higher Mn oxidation state at pH 11, while Fe kept trivalent in all samples. These results reveal that the surface interactions are closely related to the redox state of NOM and are beneficial for better understanding the speciation, immobilization, transport, and toxicity of metal ions in natural waters.


Asunto(s)
Sustancias Húmicas/análisis , Hierro/análisis , Manganeso/análisis , Contaminantes Químicos del Agua/análisis , Espectroscopía de Resonancia por Spin del Electrón , Monitoreo del Ambiente , Espectrometría por Rayos X , Espectroscopía de Absorción de Rayos X
13.
Zhonghua Yi Xue Za Zhi ; 95(32): 2603-6, 2015 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-26711608

RESUMEN

OBJECTIVE: B-cell lymphoma 9 (BCL9) as a co-activator for ß-catenin-mediated transcription is highly expressed in tumors. The aim of our study is to investigate the expression of BCL9, and its clinicopathological significance in prostate cancer (PCa). METHODS: Immunohistochemistry was conducted to analyze the expression of BCL9 in 98 PCa samples and 20 benign prostate hyperplasia (BPH) samples. The associations of BCL9 expression with clinicopathological features and prognosis in PCa patients were analyzed with various statistical methods, such as chi-square test, Kaplan-Meier method and log-rank test. RESULTS: The positive rate of BCL9 was 53.1% (52/98) in prostate cancer group, and 25.0% (5/20) in benign group (P=0.022). In addition, BCL9 expression in PCa tissues was significantly associated with Gleason score (P=0.016), and biochemical recurrence (P=0.020). Moreover, Kaplan-Meier survival analysis showed that the higher expression of BCL9 was correlated with shorter biochemical recurrence-free survival (P=0.037). However, BCL9 was not an independent prognostic predictor for biochemical recurrence-free survival in patients with PCa after the multivariate analysis was conducted (Hazard ratio =1.73, P=0.384). CONCLUSION: Our study demonstrates the up-regulation of BCL9 is associated with PCa's early diagnosis and malignant degree.


Asunto(s)
Neoplasias de la Próstata , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Proteínas de Neoplasias , Pronóstico , Hiperplasia Prostática , Factores de Transcripción , Regulación hacia Arriba
14.
Fish Physiol Biochem ; 40(5): 1521-32, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24844600

RESUMEN

The study assessed the effects of surgically implanted dummy ultrasonic transmitters on physiological response of bighead carp Hypophthalmichthys nobilis in April 2011. Before the surgery, 15 blood samples were extracted randomly from 195 bighead carp samples, and then the rest of the fish were divided into three groups: (1) control group, handing but no tagging, (2) sham group, surgical procedure without implantation of transmitter and (3) surgery group, surgical implantation of transmitters. In 3 h, 24 h, 7 days and 14 days after surgery, 15 fish were extracted randomly from the three groups, respectively, for sampling. Then the plasma samples were analyzed, and physiological measures of stress response (cortisol, glucose), tissue damage [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] and nutritional status [total protein, globulin, albumin, triglyceride, cholesterol, and alkaline phosphatase (ALP)] were compared. The result showed that there was no significant difference between sham and surgery groups in 3 h, 24 h, 7 days and 14 days after surgery. When compared to the control group, there were significant increases in concentrations of plasma cortisol, glucose, ALT, AST, total protein and globulin of sham and surgery groups in 3 h after surgery. After 24 h, the levels of plasma cortisol, ALT, AST, total protein, globulin and ALP were elevated in both sham and surgery groups, whereas the levels of plasma glucose had declined to normal level and plasma albumin, cholesterol and triglyceride were significantly decreased in both sham and surgery groups. After 7 days, the levels of plasma glucose, albumin and cholesterol continued to decline, while the level of plasma ALT, globulin and ALP had declined but still remained higher for sham and surgery groups than control group; however, the plasma total protein level had returned to normal. After 14 days, there was no significant difference between the three groups. The above results showed that surgical implantation of ultrasonic transmitters had indeed caused significantly negative effects on the physiological response of bighead carp. However, all the negative influences on stress response, tissue damage and nutritional status had disappeared in 14 days after surgery, and the presence of transmitters had no significant negative impact. Therefore, the bighead carp should be temporary cultured at least 14 days for the recovery of physiological response and then released into the free water for the ultrasonic telemetry research.


Asunto(s)
Carpas/fisiología , Carpas/cirugía , Implantes Experimentales/efectos adversos , Estrés Fisiológico/fisiología , Ultrasonido/instrumentación , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Análisis de Varianza , Animales , Aspartato Aminotransferasas/sangre , Glucemia/metabolismo , China , Colesterol/sangre , Hidrocortisona/sangre , Albúmina Sérica/metabolismo , Factores de Tiempo , Triglicéridos/sangre
15.
Sci Total Environ ; 912: 168833, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38036120

RESUMEN

Bone char is a functional material obtained by calcining animal bones and is widely used for environmental remediation. In this work, iron was inserted into porcine bone-derived bone char via ion exchange to synthesize iron-doped bone char (Fe-BC) for efficient catalysis of hydrogen peroxide. This is the first time that Fe-BC has been used as a catalyst for the activation of H2O2. The effectiveness of the Fe-BC catalyst was influenced by the annealing temperature and the amount of iron doping. The results showed that the activation of H2O2 by the Fe-BC catalyst with the best catalytic performance could achieve 97.6% of APAP degradation within 30 min. Insights from electron paramagnetic resonance (EPR), free radical scavenging experiments and linear sweep voltammetry (LSV) proposed a reaction mechanism based on free radicals dominated degradation pathways (OH and O2-). Iron served as the primary active site in Fe-BC, with defect sites and oxygen-containing groups in the catalyst also contributing to the removal of pollutants. The Fe-BC/H2O2 system demonstrated resilience to interference from common anions (Cl-, NO3-, SO42- and HCO3-) in water, but was less effective against humic acid (HA). Based on the detection of intermediates produced during APAP degradation, possible degradation pathways of APAP were proposed and the toxicity of intermediates was evaluated. This work provides fresh insights into the use of heterogeneous Fenton catalysts for the removal of organic pollutants from water.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Animales , Porcinos , Peróxido de Hidrógeno/química , Hierro/química , Acetaminofén , Agua , Oxígeno , Contaminantes Químicos del Agua/análisis , Catálisis , Oxidación-Reducción
16.
Sci Total Environ ; 920: 170982, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38367723

RESUMEN

The application of iron-doped biochar in peroxymonosulfate (PMS) activation systems has gained increasing attention due to their effectiveness and environmental friendliness in addressing environmental issues. However, the behavioral mechanism of iron doping and the detailed 1O2 generation mechanism in PMS activation systems remain ambiguous. Here, we investigated the effects of three anions (Cl-, NO3-and SO42-) on the process of iron doping into bone char, leading to the synthesis of three iron-doped bone char (Fe-ClBC, Fe-NBC and Fe -SBC). These iron-doped bone char were used to catalyze PMS to degrade acetaminophen (APAP) and exhibited the following activity order: Fe-ClBC > Fe-NBC > Fe-SBC. Characterization results indicated that iron doping primarily occurred through the substitution of calcium in hydroxyapatite within BC. In the course of the impregnation, the binding of SO42- and Ca2+ hindered the exchange of iron ions, resulting in lower catalytic activity of Fe-SBC. The primary reactive oxygen species in the Fe-ClBC/PMS and Fe-NBC/PMS systems were both 1O2. 1O2 is produced through O2•- conversion and PMS self-dissociation, which involves the generation of metastable iron intermediates and electron transfer within iron species. The presence of oxygen vacancies and more carbon defects in the Fe-ClBC catalyst facilitates 1O2 generation, thereby enhancing APAP degradation within the Fe-ClBC/PMS system. This study is dedicated to in-depth exploration of the mechanisms underlying iron doping and defect materials in promoting 1O2 generation.


Asunto(s)
Acetaminofén , Hierro , Porcinos , Animales , Hierro/química , Peróxidos/química , Oxidación-Reducción , Oxígeno
17.
Sci Total Environ ; 920: 170933, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38360324

RESUMEN

As emerging contaminants, microplastics (MPs) are becoming a matter of global concern, and they have complex interactions with dissolved organic matter (DOM) widely present in aqueous environments. Here, we investigate the molecular interactions between aged polystyrene microplastics (PS-MPs) and fulvic acid (FA) under neutral conditions using a series of analytical techniques. The structural changes of FA and the binding interactions of PS-MPs with FA at a molecular level were explored by fluorescence and FT-IR combined with two-dimensional correlation spectroscopy (2D-COS). Results showed that photoaging of PS-MPs changed the sequence of structural variations with FA. Atomic force microscopy-infrared spectroscopy (AFM-IR) strongly demonstrated that the surface roughness of both pristine and aged PS-MPs greatly increased after FA addition. Meanwhile, AFM-IR and Raman spectroscopy revealed a stronger interaction between aged PS-MPs and FA. The content of oxygen-containing functional groups in PS-MPs increased after aging and after binding with FA, and surface distribution of these functional groups also changed. XPS analyses indicated that the oxygen content in PS-MPs increased after the interaction with FA and the increase in oxygen content was even greater in aged PS-MPs. Overall, these research findings are useful to understand the environmental impacts of DOM-MPs interactions and to address the uncertainty of MPs aging effect on their environmental behavior in aquatic ecosystems.

18.
J Hazard Mater ; 469: 133984, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38460263

RESUMEN

Light-stabilizing additives may contribute to the overall pollution load of microplastics (MPs) and potentially enter the food chain, severely threatening aquatic life and human health. This study investigated the variation between polystyrene (PS) MPs and phthalocyanine blue (CuPC)-containing MPs before and after photoaging, as well as their effects on Microcystis aeruginosa. The presence of PS-MPs increased cell mortality, antioxidant enzyme activity, and the variation in extracellular components, while the presence of CuPC exacerbated these variations. CuPC-containing MPs caused different increasing trends in superoxide dismutase and malondialdehyde activities due to electron transfer across the membrane. Transcriptomic analysis revealed that the MPs and CuPC affected various cellular processes, with the greatest impact being on cell membranes. Compared with MPs, CuPC negatively affected ribosome and polysaccharide formation. These findings provide insights into the molecular mechanisms underlying the cellular response to MPs and their associated light-stabilizer pollution and imply the necessity for mitigating the pollution of both MPs and light-stabilizers.


Asunto(s)
Cianobacterias , Indoles , Microcystis , Compuestos Organometálicos , Contaminantes Químicos del Agua , Humanos , Microplásticos/toxicidad , Plásticos/toxicidad , Antioxidantes , Poliestirenos , Contaminantes Químicos del Agua/toxicidad
19.
Sci Total Environ ; 913: 169623, 2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38159742

RESUMEN

Infrared (IR) spectroscopy is a powerful technique for detecting and identifying Microplastics (MPs) in the environment. However, the aging of MPs presents a challenge in accurately identification and classification. To address this challenge, a classification model based on deep convolutional neural networks (CNNs) was developed using infrared spectra results. Particularly, original infrared (IR) spectra were used as the sample dataset, therefore, relevant spectral details were preserved and additional noise or distortions were not introduced. The Adam (Adaptive moment estimation) algorithm was employed to accelerate gradient descent and weight update, the Dropout function was implemented to prevent overfitting and enhance the generalization performance of the network. An activation function ReLu (Rectified Linear Unit) was also utilized to simplify the co-adaptation relationship among neurons and prevent gradient disappearance. The performance of the CNN model in MPs classification was evaluated based on accuracy and robustness, and compared with other machine learning techniques. CNN model demonstrated superior capabilities in feature extraction and recognition, and greatly simplified the pre-processing procedure. The identification results of aged commercial microplastic samples showed accuracies of 40 % for Artificial Neural Network, 60 % for Random Forest, 80 % for Deep Neural Network, and 100 % for CNN, respectively. The CNN architecture developed in this work also demonstrates versatility by being suitable for both limited data cases and potential expansion to include more discrete data in the future.

20.
Environ Int ; 184: 108466, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38310816

RESUMEN

The selective removal of targeted pollutants from complex wastewater is challenging. Herein, a novel persulfate (PS)-based advanced oxidation system equipped with a series of two-dimensional (2D) bimetallic oxide nanosheets (NSs) catalysts is developed to selectively degrade bisphenol A (BPA) within mixed pollutants via initiating nonradical-induced polymerization. Results indicate that the Ni0.60Co0.40Ox NSs demonstrate the highest catalytic efficiency among all Ni-Co NSs catalysts. Specifically, BPA degradation rate is 47.34, 27.26, and 9.72 times higher than that of 4-chlorophenol, phenol, and 2,4-dichlorophenol in the mixed solution, respectively. The lower oxidative potential of BPA in relation to the other pollutants renders it the primary target for oxidation within the PDS activation system. PDS molecules combine on the surface of Ni0.60Co0.40Ox NSs to form the surface-activated complex, triggering the generation of BPA monomer radicals through H-abstraction or electron transfer. These radicals subsequently polymerize on the surface of the catalyst through coupling reactions. Importantly, this polymerization process can occur under typical aquatic environmental conditions and demonstrates resistance to background matrices like Cl- and humic acid due to its inherent nonradical attributes. This study offers valuable insights into the targeted conversion of organic pollutants in wastewater into value-added polymers, contributing to carbon recycle and circular economy.


Asunto(s)
Compuestos de Bencidrilo , Contaminantes Ambientales , Contaminantes Químicos del Agua , Óxidos , Aguas Residuales , Oxidación-Reducción , Fenoles/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA