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1.
J Environ Manage ; 354: 120406, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38373376

RESUMO

Mitigating the adverse effects of stressful environments on crops and promoting plant recovery in contaminated sites are critical to agricultural development and environmental remediation. Iron-based nanomaterials (Fe NMs) can be used as environmentally friendly nano-fertilizer and as a means of ecological remediation. A meta-analysis was conducted on 58 independent studies from around the world to evaluate the effects of Fe NMs on plant development and antioxidant defense systems in stressful environments. The application of Fe NMs significantly enhanced plant biomass (mean = 25%, CI = 20%-30%), while promoting antioxidant enzyme activity (mean = 14%, CI = 10%-18%) and increasing antioxidant metabolite content (mean = 10%, CI = 6%-14%), reducing plant oxidative stress (mean = -15%, CI = -20%∼-10%), and alleviating the toxic effects of stressful environments. The observed response was dependent on a number of factors, which were ranked in terms of a Random Forest Importance Analysis. Plant species was the most significant factor, followed by Fe NM particle size, duration of application, dose level, and Fe NM type. The meta-analysis has demonstrated the potential of Fe NMs in achieving sustainable agriculture and the future development of phytoremediation.


Assuntos
Ferro , Nanoestruturas , Antioxidantes , Agricultura , Produtos Agrícolas
2.
Adv Sci (Weinh) ; 11(14): e2306827, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38308184

RESUMO

Cholesterol metabolism has important roles in maintaining membrane integrity and countering the development of diseases such as obesity and cancers. Cancer cells sustain cholesterol biogenesis for their proliferation and microenvironment reprograming even when sterols are abundant. However, efficacy of targeting cholesterol metabolism for cancer treatment is always compromised. Here it is shown that CSN6 is elevated in HCC and is a positive regulator of hydroxymethylglutaryl-CoA synthase 1 (HMGCS1) of mevalonate (MVA) pathway to promote tumorigenesis. Mechanistically, CSN6 antagonizes speckle-type POZ protein (SPOP) ubiquitin ligase to stabilize HMGCS1, which in turn activates YAP1 to promote tumor growth. In orthotopic liver cancer models, targeting CSN6 and HMGCS1 hinders tumor growth in both normal and high fat diet. Significantly, HMGCS1 depletion improves YAP inhibitor efficacy in patient derived xenograft models. The results identify a CSN6-HMGCS1-YAP1 axis mediating tumor outgrowth in HCC and propose a therapeutic strategy of targeting non-alcoholic fatty liver diseases- associated HCC.


Assuntos
Carcinoma Hepatocelular , Hidroximetilglutaril-CoA Sintase , Neoplasias Hepáticas , Proteínas Repressoras , Proteínas de Sinalização YAP , Humanos , Carcinoma Hepatocelular/metabolismo , Colesterol/metabolismo , Hidroximetilglutaril-CoA Sintase/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Microambiente Tumoral , Ubiquitina/metabolismo , Proteínas de Sinalização YAP/metabolismo
3.
J Hazard Mater ; 465: 133265, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38113745

RESUMO

In situ anoxic bioremediation is a sustainable technology to remediate PAHs contaminated soils. However, the limited degradation rate of PAHs under anoxic conditions has become the primary bottleneck hindering the application of this technology. In this study, coupled low-temperature thermally treatment (<50 °C) and EA biostimulation was used to enhance PAH removal. Anoxic biodegradation of PAHs in soil was explored in microcosms in the absence and presence of added EAs at 3 temperatures (15 °C, 30 °C, and 45 °C). The influence of temperature, EA, and their interaction on the removal of PAHs were identified. A PAH degradation model based on PLSR analysis identified the importance and the positive/negative role of parameters on PAH removal. Soil archaeal and bacterial communities showed similar succession patterns, the impact of temperature was greater than that of EA. Soil microbial community and function were more influenced by temperature than EAs. Close and frequent interactions were observed among soil bacteria, archaea, PAH-degrading genes and methanogenic genes. A total of 15 bacterial OTUs, 1 PAH-degrading gene and 2 methanogenic genes were identified as keystones in the network. Coupled low-temperature thermally treatment and EA stimulation resulted in higher PAH removal efficiencies than EA stimulation alone and low-temperature thermally treatment alone.


Assuntos
Euryarchaeota , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Solo , Temperatura , Biodegradação Ambiental , Elétrons , Poluentes do Solo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Euryarchaeota/metabolismo , Microbiologia do Solo
4.
Signal Transduct Target Ther ; 8(1): 187, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37202390

RESUMO

Continuous de novo fatty acid synthesis is required for the biosynthetic demands of tumor. FBXW7 is a highly mutated gene in CRC, but its biological functions in cancer are not fully characterized. Here, we report that FBXW7ß, a FBXW7 isoform located in the cytoplasm and frequently mutated in CRC, is an E3 ligase of fatty acid synthase (FASN). Cancer-specific FBXW7ß mutations that could not degrade FASN can lead to sustained lipogenesis in CRC. COP9 signalosome subunit 6 (CSN6), an oncogenic marker of CRC, increases lipogenesis via interacting with and stabilizing FASN. Mechanistic studies show that CSN6 associates with both FBXW7ß and FASN, and antagonizes FBXW7ß's activity by enhancing FBXW7ß autoubiquitination and degradation, which in turn prevents FBXW7ß-mediated FASN ubiquitination and degradation, thereby regulating lipogenesis positively. Both CSN6 and FASN are positively correlated in CRC, and CSN6-FASN axis, regulated by EGF, is responsible for poor prognosis of CRC. The EGF-CSN6-FASN axis promotes tumor growth and implies a treatment strategy of combination of orlistat and cetuximab. Patient-derived xenograft experiments prove the effectiveness of employing orlistat and cetuximab combination in suppressing tumor growth for CSN6/FASN-high CRC. Thus, CSN6-FASN axis reprograms lipogenesis to promote tumor growth and is a target for cancer intervening strategy in CRC.


Assuntos
Neoplasias Colorretais , Lipogênese , Humanos , Cetuximab , Neoplasias Colorretais/genética , Fator de Crescimento Epidérmico , Proteína 7 com Repetições F-Box-WD/genética , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintases/genética , Lipogênese/genética , Orlistate
5.
J Environ Manage ; 325(Pt B): 116407, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302302

RESUMO

The proportion of activated persulfate (PS) oxidation technology in the remediation of domestic organic contaminated sites has increased every year, and the potential corrosion risk of site reuse caused by residual oxidants and by-products has also attracted the attention of researchers. In this work, the potential corrosion degree such as the mass reduction rate and surface crack width of standard iron flakes under different conditions, including with different PS dosages and release times, was monitored quantitatively over a long period, and the corresponding corrosion risk was quantitatively assessed. The results showed that when n (Na2S2O8):n (PAHs) increased from 5:1 to 100:1, the higher the oxidizer dosage, the more severe the corrosion weight loss and surface crack width, indicating that the oxidizer dosage was positively correlated with the potential corrosion risk. In addition, the corrosion crack width of the standard iron flake had a significant positive correlation with the reaction time and a significant negative correlation with the mass change. According to the changes in the standard iron flake, the corrosion process could be divided into three stages, in which the corrosion risk from high to low followed the order of oxidant corrosion stage > oxidant and salt corrosion stage > salt and microbial corrosion stage. Therefore, the dosage of chemicals should be controlled, the molar ratio of oxidizer to contaminant should not exceed 25:1, and a natural recovery period of at least one year should be left post remediation. During the reuse of the remediation sites in the future, the potential corrosion risks should also be calculated based on the dosage and time, to avoid redevelopment and use of the restoration site in the high corrosion risk stage.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Poluentes do Solo/análise , Corrosão , Oxirredução , Ferro , Oxidantes , Solo , Sulfatos
6.
Cell Discov ; 8(1): 130, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473865

RESUMO

Chromodomain helicase DNA binding protein (CHD) family plays critical roles in regulating gene transcription. The family is linked to cancer disease, but the family member's role in tumorigenesis remains largely unknown. Here, we report that CHD6 is highly expressed in colorectal cancer (CRC). CHD6 knockdown inhibited cancer cell proliferation, migration, invasion, and tumorigenesis. Consistently, Villin-specific Chd6 knockout in mice attenuates cancer formation in AOM/DSS model. We found that aberrant EGF signals promoted the stability of CHD6 by diminishing ubiquitin-mediated degradation. EGF signal inhibits GSK3ß activity, which in turn prevents phosphodegron formation of CHD6, thereby hindering E3 ligase FBXW7-mediated CHD6 ubiquitination and degradation. CHD6's chromatin remodeler activity engages in binding Wnt signaling transcription factor TCF4 to facilitate the transcriptional expression of TMEM65, a mitochondrial inner membrane protein involved in ATP production and mitochondrial dynamics. In addition, Wnt signaling is also an upstream regulator of CHD6. CHD6 promoter contains TCF4 and ß-catenin binding site, and CHD6 can be transcriptionally activated by Wnt ligand to facilitate TMEM65 transcription. Thus CHD6-TMEM65 axis can be regulated by both EGF and Wnt signaling pathways through two different mechanisms. We further illustrate that CHD6-TMEM65 axis is deregulated in cancer and that co-administration of Wnt inhibitor LGK974 and the anti-EGFR monoclonal antibody cetuximab largely restricted the growth of patient-derived xenografts of CRC. Targeting CHD6-TMEM65 axis may be effective for cancer intervention.

7.
Microbiome ; 10(1): 75, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538590

RESUMO

BACKGROUND: The deep sea harbors the majority of the microbial biomass in the ocean and is a key site for organic matter (OM) remineralization and storage in the biosphere. Microbial metabolism in the deep ocean is greatly controlled by the generally depleted but periodically fluctuating supply of OM. Currently, little is known about metabolic potentials of dominant deep-sea microbes to cope with the variable OM inputs, especially for those living in the hadal trenches-the deepest part of the ocean. RESULTS: In this study, we report the first extensive examination of the metabolic potentials of hadal sediment Chloroflexi, a dominant phylum in hadal trenches and the global deep ocean. In total, 62 metagenome-assembled-genomes (MAGs) were reconstructed from nine metagenomic datasets derived from sediments of the Mariana Trench. These MAGs represent six novel species, four novel genera, one novel family, and one novel order within the classes Anaerolineae and Dehalococcoidia. Fragment recruitment showed that these MAGs are globally distributed in deep-sea waters and surface sediments, and transcriptomic analysis indicated their in situ activities. Metabolic reconstruction showed that hadal Chloroflexi mainly had a heterotrophic lifestyle, with the potential to degrade a wide range of organic carbon, sulfur, and halogenated compounds. Our results revealed for the first time that hadal Chloroflexi harbor pathways for the complete hydrolytic or oxidative degradation of various recalcitrant OM, including aromatic compounds (e.g., benzoate), polyaromatic hydrocarbons (e.g., fluorene), polychlorobiphenyl (e.g., 4-chlorobiphenyl), and organochlorine compounds (e.g., chloroalkanes, chlorocyclohexane). Moreover, these organisms showed the potential to synthesize energy storage compounds (e.g., trehalose) and had regulatory modules to respond to changes in nutrient conditions. These metabolic traits suggest that Chloroflexi may follow a "feast-or-famine" metabolic strategy, i.e., preferentially consume labile OM and store the energy intracellularly under OM-rich conditions, and utilize the stored energy or degrade recalcitrant OM for survival under OM-limited condition. CONCLUSION: This study expands the current knowledge on metabolic strategies in deep-ocean Chlorolfexi and highlights their significance in deep-sea carbon, sulfur, and halogen cycles. The metabolic plasticity likely provides Chloroflexi with advantages for survival under variable and heterogenic OM inputs in the deep ocean. Video Abstract.


Assuntos
Chloroflexi , Carbono/metabolismo , Chloroflexi/genética , Ecossistema , Oceanos e Mares , Enxofre/metabolismo
8.
Sci Total Environ ; 835: 155313, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35476951

RESUMO

The quality of agricultural soils is important for agricultural production and food safety. The contamination of agricultural soils by heavy metal(loid)s (HMs) has aroused global attention. Fifty-two topsoil samples with 8 HMs were gathered to assess the health risks of farmland soil in Huairou District, Beijing. As a significantly enriched pollutant, the results revealed that Hg had greater ecological risks relative to other HMs. We found that the positive matrix factorization (PMF) model appears to be more physically plausible in identifying complex pollution sources compared to the absolute principal components score-multiple linear regression (APCS-MLR) model, which had a higher fit coefficient (r2 = 0.69-0.99). Five HMs from pollution sources, including agricultural activities, traffic source, natural source, fuel burning, and industrial production, were identified by integrating the PMF model with Pearson's correlation analysis, revealing corresponding contribution rates of 29.40%, 22.54%, 20.16%, 15.20%, and 12.70%, respectively. The probabilistic health risk evaluation results showed an absence of non-carcinogenic risks in all populations, but the carcinogenic risk could not be ignored, especially in children. In addition, the source-oriented health risks showed that agricultural activities made the largest contribution to the health risks of all populations. This research provides scientific evidence for preventing HMs contamination and control of farmland.


Assuntos
Metais Pesados , Poluentes do Solo , Pequim , Criança , China , Monitoramento Ambiental , Fazendas , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
9.
Mar Life Sci Technol ; 4(1): 150-161, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37073355

RESUMO

Hadal trenches are the least explored marine habitat on earth. Archaea has been shown to be the dominant group in trench sediments. However, the activity potentials and detailed diversity of these communities as well as their inter-trench variations are still not known. In this study, we combined datasets from two pairs of primers to investigate at high resolution the structure and activity potentials of the archaeal communities in vertically sectioned sediment cores taken from the deepest points of the Mariana (10,853 m) and Mussau (7011 m) trenches. The compositions of the potentially active communities revealed, via 16S ribosomal RNA gene (rDNA) and RNA (rRNA), significant differences between samples. Marine Group I (MGI), with nine identified subgroups, was the most dominant class in the active archaeal communities of the two trenches. Significantly different species composition and vertical variations were observed between the two trenches. Vertical transitions from aerobic MGI α to anaerobic MGI η and υ subgroups were observed in MST but not in MT sediments, which might be related to the faster microbial oxygen consumption in MST. These results provide a better understanding on archaeal activity and diversity in trench sediments. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-021-00105-y.

10.
FEMS Microbiol Lett ; 368(13)2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160584

RESUMO

Microbial degradation of organic matter along the vertical profile of the water column is a major process driving the carbon cycle in the ocean. Pseudoalteromonas has been identified as a dominant genus in pelagic marine environments worldwide, playing important roles in the remineralization of organic carbon. However, the current understanding of Pseudoalteromonas was mainly based on shallow water populations or cultivated species. This study analyzed for the first time the structure, activity potential and ecotypes differentiation of Pseudoalteromonas in the water column of the New Britain Trench (NBT) down to 6000 m. Analysis on diversities of the 16S rRNA gene and their transcripts showed that Pseudoalteromonas was greatly enriched in deep-sea waters and showed high activity potentials. The deep-sea Pseudoalteromonas were significantly different from their shallow-water counterparts, suggesting an obvious ecotype division along with the vertical profile. Phylogenetic analysis on the 16S rRNA gene and hsp60 gene of 219 Pseudoalteromonas strains isolated from different depths further showed that the vertical ecotype division could even occur at the strain level, which might be a result of long-term adaptation to environmental conditions at different depths. The discovered depth-specific strains provide valuable models for further studies on adaptation, evolution and functions of the deep-sea Pseudoalteromonas.


Assuntos
Ecótipo , Pseudoalteromonas/isolamento & purificação , Água do Mar/microbiologia , DNA Bacteriano/genética , Filogenia , Pseudoalteromonas/classificação , Pseudoalteromonas/genética , Pseudoalteromonas/metabolismo , RNA Ribossômico 16S/genética , Água do Mar/análise , Reino Unido
11.
Huan Jing Ke Xue ; 42(3): 1123-1130, 2021 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742908

RESUMO

A life cycle conceptual site model (LC-CSM) can represent the actual spatial distribution and migration of pollution of a site very accurately and be beneficial in supporting decisions for accurate site remediation or risk management. A volatile chlorinated hydrocarbon contaminated site in the Beijing-Tianjin-Hebei region was chosen as the study case. LC-CSMs were established following the site assessment, preliminary investigation, detailed investigation, and supplementary investigation of each stage. The application of field screening tests such as a membrane interface probe and the multi-electrode resistivity method assisted in identifying potential pollution sources and hot points. Concurrently, a large amount of vinyl chloride, the end product of chlorinated hydrocarbon degradation, was detected in some boreholes, indicating that pollutant biodegradation had occurred at this site. Some typical boreholes and cross-sections were chosen to analyze the biodegradation indicators and chemical fingerprints, combining the results of the comprehensive score of chlorinated hydrocarbon anaerobic biodegradability in groundwater reaching 22. It is judged that the site has strong anaerobic biodegradability. This step-by-step optimization forms an LC-CSM for site investigation, which provides scientific support for accurate site characterization.

12.
Environ Geochem Health ; 43(1): 23-36, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32696201

RESUMO

Soil pollution at industrial sites is an important issue in China and in most other regions of the world. The accurate prediction of the spatial distribution of pollutants at contaminated industrial sites is a requirement for the development of most soil remediation strategies, and is commonly performed using spatial interpolation methods. However, significant and abrupt variations in the spatial distribution of pollutants decrease prediction accuracy. During this study, the use of partition interpolation methods was applied to benzo fluoranthene in four soil layers at a contaminated site to determine their ability to improve prediction accuracy in comparison to unpartitioned methods. The examined methods for partitioned interpolation included inverse distance weighting (IDW), radial basis function (RBF), and ordinary kriging (OK). The prediction results of the three methods for partitioned interpolation were compared, and the applicability of partition interpolation was determined. The prediction error associated with the partitioned interpolation methods decreased by 70% compared to unpartitioned interpolation. The prediction accuracy of IDW-based partition interpolation was higher than that of RBF- and OK-based partition interpolation techniques, and it was suitable for identification of highly polluted areas. Partition interpolation is also applicable to 12 other PAHs controlled by USEPA that can be detected, and the prediction effects could also verify this interpolation choice. In addition, the results also demonstrated that the more the maximum concentration deviated from the "norm", the greater the prediction error was caused by the smoothing effects of the interpolation models. These results suggest that the partition interpolation with IDW method can be effectively used to obtain relatively accurate spatial contaminant distribution information, and to identify highly polluted areas.


Assuntos
Monitoramento Ambiental/métodos , Poluentes do Solo/análise , China , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Fluorenos/análise , Previsões , Análise Espacial
13.
Front Microbiol ; 11: 1521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765444

RESUMO

Surprisingly high rates of microbial respiration have recently been reported in hadal trench sediment, yet the potentially active microorganisms and specific microbe-microbe relationships in trench sediment are largely unknown. We investigated the bulk and active prokaryotic communities and co-occurrence interactions of different lineages in vertically sectioned sediment cores taken from the deepest points of the Mariana and Mussau Trenches. Analysis on species novelty revealed for the first time the high rate of novel lineages in the microbial communities of the hadal trenches. Using 95, 97, and 99% similarity as thresholds, averagely 22.29, 32.3, and 64.1% of total OTUs retrieved from sediments of the two trenches were identified as the potentially novel lineages, respectively. The compositions of the potentially active communities, revealed via ribosomal RNA (rRNA), were significantly different from those of bulk communities (rDNA) in all samples from both trenches. The dominant taxa in bulk communities generally accounted for low proportions in the rRNA libraries, signifying that the abundance was not necessarily related to community functions in the hadal sediments. The potentially active communities showed high diversity and composed primarily of heterotrophic lineages, supporting their potential contributions in organic carbon consumption. Network analysis revealed high modularity and non-random co-occurrence of phylogenetically unrelated taxa, indicating highly specified micro-niches and close microbial interactions in the hadal sediments tested. Combined analysis of activity potentials and network keystone scores revealed significance of phyla Chloroflexi and Gemmatimonadetes, as well as several potentially alkane-degrading taxa in maintaining microbial interactions and functions of the trench communities. Overall, our results demonstrate that the hadal trenches harbor diverse, closely interacting, and active microorganisms, despite the extreme environmental conditions.

14.
Br J Cancer ; 123(6): 1042-1044, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647365

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
Br J Cancer ; 122(11): 1673-1685, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32225170

RESUMO

BACKGROUND: Cancer stem cells (CSCs) are responsible for tumour initiation, metastasis and recurrence. However, the mechanism of CSC formation, maintenance and expansion in colorectal cancer (CRC) remains poorly characterised. METHODS: The role of COP9 signalosome subunit 6 (CSN6) in regulating cancer stemness was evaluated by organoid formation and limited dilution analysis. The role of CSN6-TRIM21-OCT1-ALDH1A1 axis in CSC formation was evaluated in vitro and in vivo. The association of CSN6, TRIM21 and ALDH1A1 expression was validated by a tissue microarray with 267 CRC patients. RESULTS: The results showed that CSN6 is critical for sphere formation and maintaining the growth of patient-derived organoids (PDOs). We characterised the role of CSN6 in regulating cancer stemness, which involves the TRIM21 E3 ubiquitin ligase, transcription factor POU class 2 homeobox 1 (OCT1) and cancer stem cell marker aldehyde dehydrogenase 1 A1 (ALDH1A1). Our data showed that CSN6 facilitates ubiquitin-mediated degradation of TRIM21, which in turn decreases TRIM21-mediated OCT1 ubiquitination and subsequently stabilises OCT1. Consequently, OCT1 stabilisation leads to ALDH1A1expression and promotes cancer stemness. We further showed that the protein expression levels of CSN6, TRIM21 and ALDH1A1 can serve as prognostic markers for human CRC. CONCLUSIONS: In conclusion, we validate a pathway for cancer stemness regulation involving ALDH1A1 levels through the CSN6-TRIM21 axis, which may be utilised as CRC molecular markers and be targeted for therapeutic intervention in cancers.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Complexo do Signalossomo COP9/metabolismo , Carcinogênese/metabolismo , Neoplasias Colorretais/patologia , Células-Tronco Neoplásicas/patologia , Ribonucleoproteínas/metabolismo , Carcinogênese/patologia , Neoplasias Colorretais/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo
16.
Environ Pollut ; 261: 114133, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32078879

RESUMO

Biochar has a wide range of feedstocks, and different feedstocks often resulted in different properties, such as element distribution and heavy metal immobilization performance. In this work, batch experiments were conducted to assess the effectiveness of biochar pyrolyzed from kitchen waste (KWB), corn straw (CSB), and peanut hulls (PHB) on immobilization of Cd and Pb in contaminated soil by planting swamp cabbage (Ipomoea aquatica Forsk.) with a combination of toxicological and physiological tests. The results showed that biochar could all enhance the soil pH, and reduce extractable Pb and Cd in soil by 22.61%-71.01% (KWB), 18.54%-64.35% (CSB), and 3.28%-60.25% (PHB), respectively. The biochar led to a drop in Cd and Pb accumulation in roots, stems, and leaves by 45.43%-97.68%, 59.13%-96.64%, and 63.90%-99.28% at the dosage of 60.00 mg/kg, respectively. The root length and fresh weight of swamp cabbage were promoted, while superoxide dismutase (SOD) and peroxidase (POD) decreased after biochar treatment. The distribution of heavy metal fractions before and after biochar treatment indicated that biochar could transform Cd and Pb into a state of lower bioavailability, thus inhibiting Cd and Pb uptake by swamp cabbage. Biochar with different feedstocks could be ranked by the following order according to immobilization performance: KWB > CSB > PHB.


Assuntos
Oryza , Poluentes do Solo/análise , Arachis , Cádmio/análise , Carvão Vegetal , Chumbo , Solo , Zea mays
17.
Environ Sci Pollut Res Int ; 27(9): 9126-9134, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916167

RESUMO

In this study, corn stalk was modified by manganese (Mn) before (MBC1) and after (MBC2) pyrolysis at different temperatures (400~600 °C) under anaerobic conditions for Cd sorption in both water and soil. Batch experiments in aqueous solution were conducted to evaluate the optimum sorption capability by biochar with and without manganese-modified. Both types of manganese modification can improve the sorption capacity of Cd(II) on biochar, which is superior to the corresponding pristine biochar without modification, especially, pyrolyzed at 500 °C with 5:1 modification ratio. Under the optimal preparation conditions, the sorption percentage on MBC2 was 11.01% higher than that of MBC1. The maximum sorption capacity of MBC2 was 191.94 mg g-1 calculated by isotherm model. The performance of MBC2 was also verified in soil stabilization experiments in Cd-contaminated soil. We can conclude from the results of BCR extraction that all the application rates of MBC2 (1%, 2%, and 3%) can reduce the mild acid-soluble fraction Cd. The reducible, oxidizable, and residual fraction Cd showed an upward trend, thus controlling the migration, transformation, and enrichment of Cd in soil. The characteristic analysis showed biochar has more irregular fold and more particle-aggregated surface after modification. The main components of these aggregated particles are manganese oxides (MnOx) with high sorption capacity, such as the MnOx crystal structure loaded on MBC2 is a mixed structure of δ-MnO2 and MnO. However, these particles may block the biochar pores, or some of the pores may collapse at high temperatures during the modification process. The specific surface area was reduced, even if the sorption effect of MBC was strongly enhanced. Meanwhile, under the action of the secondary pyrolysis of MBC2 modification process, the MBC2 has a higher degree of aromatization with more potential active sorption sites for Cd. The study concluded that the MBC2 could be a promising amendment for Cd in both water and soil real field applications.


Assuntos
Cádmio , Carvão Vegetal/química , Compostos de Manganês/química , Óxidos/química , Poluentes do Solo , Adsorção , Solo
18.
Environ Sci Pollut Res Int ; 27(9): 8991-8999, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31321730

RESUMO

Nowadays, the remediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soil has received wide attention. In this work, Ochrobactrum sp. (PW) was isolated through selective enrichment from PAHs-contaminated soil in coking plant of Beijing, and the effects of PW on phytoremediation of that soil by alfalfa (Medicago sativa L.) and ryegrass (Lolium multiflorum Lam.) were investigated through pot experiments. Plant biomass, peroxidase (POD) activity, malondialdehyde (MDA) contents, soil enzyme activity (polyphenol oxidase and dehydrogenase activity), and residual concentration of PAHs in soils were determined to illustrate the ability of PW for enhancing the degradation of PAHs by plants. The results showed that the fresh weight of ryegrass and alfalfa inoculated with PW was significantly (p < 0.05) increased while the activity of POD and MDA contents were notably (p < 0.05) reduced than that without inoculation. Additionally, PW enhanced the activity of polyphenol oxidase and dehydrogenase in soil significantly (p < 0.05), and further enhanced the degradability of the system to PAHs. Different treatment methods could be ranked by the following order according to the degradability: SP (alfalfa + PW) > RP (ryegrass + PW) > PW (PW) > S (alfalfa) > R (ryegrass). The combined action of PW and alfalfa/ryegrass could accelerate the degradability of PAHs from soil contaminated by coking plants. PW could be used as potential bacteria to promote phytoremediation of the soil contaminated by PAHs.


Assuntos
Ochrobactrum , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo/análise , Pequim , Biodegradação Ambiental , Solo , Microbiologia do Solo
19.
Cell Res ; 30(2): 163-178, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31772275

RESUMO

The Serine-Glycine-One-Carbon (SGOC) pathway is pivotal in multiple anabolic processes. Expression levels of SGOC genes are deregulated under tumorigenic conditions, suggesting participation of oncogenes in deregulating the SGOC biosynthetic pathway. However, the underlying mechanism remains elusive. Here, we identified that Interleukin enhancer-binding factor 3 (ILF3) is overexpressed in primary CRC patient specimens and correlates with poor prognosis. ILF3 is critical in regulating the SGOC pathway by directly regulating the mRNA stability of SGOC genes, thereby increasing SGOC genes expression and facilitating tumor growth. Mechanistic studies showed that the EGF-MEK-ERK pathway mediates ILF3 phosphorylation, which hinders E3 ligase speckle-type POZ protein (SPOP)-mediated poly-ubiquitination and degradation of ILF3. Significantly, combination of SGOC inhibitor and the anti-EGFR monoclonal antibody cetuximab can hinder the growth of patient-derived xenografts that sustain high ERK-ILF3 levels. Taken together, deregulation of ILF3 via the EGF-ERK signaling plays an important role in systemic serine metabolic reprogramming and confers a predilection toward CRC development. Our findings indicate that clinical evaluation of SGOC inhibitor is warranted for CRC patients with ILF3 overexpression.


Assuntos
Neoplasias Colorretais/metabolismo , Proteínas do Fator Nuclear 90/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Serina/biossíntese , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Fator de Crescimento Epidérmico/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Glicina/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Prognóstico , Ligação Proteica , Estabilidade Proteica , Estabilidade de RNA/genética , Especificidade por Substrato , Análise de Sobrevida , Ubiquitina-Proteína Ligases/metabolismo
20.
Sci Total Environ ; 707: 136064, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31865092

RESUMO

Arsenic (As) is an environmentally hazardous contaminant and can be a serious threat to human health. In China, the remediation needs for a large number of As-contaminated sites renders a strong demand for efficient remedial reagents and cost-effective approaches. In this study, a novel starch-modified FeMn binary oxide (SFM), an amorphous colloidal material, has been synthesized as a remedial reagent and its As stabilization performance has been evaluated. A set of laboratory batch experiments were carried out with SFM of different dosages directly added into three contaminated soils to immobilize As. Results demonstrated that SFM could transform As in soil from non-specifically and specifically sorbed fractions to the more stable form bounded to amorphous iron hydrous oxides, thus reducing the As concentration in TCLP leachates by up to 93.2%. Results from adsorption tests and microscopic analysis indicated that the interactions between SFM and As are mainly controlled by adsorption, oxidation, and precipitation processes. SFM has abundant surface hydroxyl groups, with excellent adsorption properties for both As(V) and As(III), with the maximum adsorption capacities of 160.63 and 284.64 mg/g respectively at pH 7.0. The adsorption process closely fitted pseudo second-order kinetics and Freundlich isotherm model. SFM could increase soil Eh and oxidize As(III) to As(V), which facilitated the As stabilization in soil. Colloidal iron-based material directly used for stabilization in As contaminated soils is reported here for the first time. Starch modification improves both the reactivity and mobility of the stabilization agent in soil. Our findings propose an efficient and convenient reagent for As remediation in soil.

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