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In the current study, a typical Sb mine was selected to explore the microbial community composition and assembly driven by the cocontamination of As/Sb with geographic distance. Our results showed that environmental parameters, especially pH, TOC, nitrate, total and bioavailable As/Sb contents largely affected the microbial community diversity and composition. The total and bioavailable As/Sb levels were significantly positively correlated with the relative abundance of Zavarzinella, Thermosporothrix and Holophaga, while the pH presented a significant negative correlation with the three genera, potentially implying they are important taxonomic groups in acid-mining soils. The cooccurrence network analysis indicated the environmental stress dominated by pH and As/Sb co-contamination affected the microbial modularity and interaction. Meanwhile, Homogeneous selection (HoS, 26.4-49.3%), and drift and others (DR, 27.1â¼40.2%) were the most important assembly processes for soil bacterial, and the importance of HoS decreased and the DR increased with geographic distance to the contamination source respectively. Soil pH, nutrient availability, total and bioavailable As/Sb contents significantly affected the HoS and DR processes. This study provides theoretical support for microbial remediation in metal(loid)-contaminated soils.
Assuntos
Arsênio , Microbiota , Poluentes do Solo , Antimônio , Arsênio/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Solo/químicaRESUMO
Oleic acid desaturase (FAD2) is the key enzyme that produces polyunsaturated fatty acids in rapeseed (Brassica napus L), which is one of the main oil crops. RNA interference (RNAi) is an emerging technique that provides new opportunities for the generation of new traits in plants. To increase oleic acid content and reduce linoleic and linolenic acid content in rapeseed, we constructed an ihpRNA plant expression vector of the FAD2 gene and obtained transgenic plants for multiple generations by stable inheritance. In this study, third-generation transgenic plants (T3), seventh-generation transgenic plants (T7), and wild-type plants (WT) were used. The differences in microbial community diversity between transgenic plants and wild-type plants and the up- and downregulation of rhizosphere metabolite contents were investigated. In conclusion, the results showed that the soil microbial community structure was stable, the general microbial community structure was not changed by the transgenic rhizosphere exudates, and no significant harmful root exudate of transgenic rapeseed on the environment was found through the microbial community and metabolomics analysis. This work may provide an understanding of the impact of RNAi on plant metabolites and a safety evaluation method for transgenic plants and a reference for rapeseed breeding.
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In this study, lead(II) sulfide (PbS) nanocrystals were modified on nickel(II)oxide nanosheets (NiO NSs) via the chemical bath method. Afterwards, Au nanoparticles (NPs) were also modified successfully. A photoelectrochemical (PEC) self-powered platform for detecting sarcosine with high PEC activity was constructed. The capacity of NiO NSs to be loaded with other sensitizing materials was mainly attributed to its porous structure and large specific surface area. Under optimum conditions, the constructed PEC self-powered cathodic sensor for detecting sarcosine exhibited a linear range in 5.0 × 10-8-5.0 × 10-2 mol/L with a detection limit (LOD) of 1.7 × 10-8 mol/L. The biosensor demonstrated good reproducibility, acceptable stability and high specificity, thus confirming its potential application in the detection of other similar substances.
Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Reprodutibilidade dos Testes , SarcosinaRESUMO
The total contents and chemical speciation analysis of Zn, Cu, Pb, Cr, Mn, Ni, Cd, and As in pig manure (PM), liquefaction residues (LRs), and bio-oils (BOs) derived from PM by liquefaction with ethanol as a solvent at 180-300 °C were thoroughly investigated in this study. The environment risk assessment, leachability, and bioavailability of heavy metals in PM and LRs were studied. The results showed that more than 75% of heavy metals remained in LRs. The total contents of heavy metals in LRs were markedly elevated, but those in BOs gradually decreased with the increase in liquefaction temperature. Moreover, the acid soluble/exchangeable fraction and reducible fraction (F1 + F2) of heavy metals in LRs and BOs was significantly reduced, while oxidizable fraction and stable fraction (F3 + F4) desirably increased after liquefaction. Furthermore, the potential risk of heavy metals in LRs was decreased in comparison to that in PM, but the risk of Pb, Mn, and As had not been obviously reduced; therefore, the LRs from the liquefaction of PM should be pretreated before recycling. Temperatures from 220 to 260 °C were the optimum conditions for disposing of PM by liquefaction with ethanol.
Assuntos
Esterco , Metais Pesados , Animais , Óleos de Plantas , Polifenóis , Medição de Risco , SuínosRESUMO
In paddy soil, the root exudates strongly influence the microbial activity and soil organic matter (SOM) mineralisation. However, the stoichiometric regulation of the mineralisation of root exudates and their priming effect on paddy soil remains unclear. Thus, we used manipulative laboratory incubations to measure the mineralisation of root exudates and the subsequent priming effect in paddy soil under different stoichiometric conditions. In this study, root exudates (simulated by 13C-labelled glucose, alanine, and oxalic acid) were added to the paddy soil along with four different amounts of N and P. The addition of simulated root exudates (SREs) enhanced the total CO2 and CH4 emissions. The mineralisation of SREs decreased by 20-45% after the addition of N and P when compared with exclusive SREs application. The addition of N and P inhibited the SREs-derived CH4 emissions when compared with SREs application alone. The mineralisation of soil organic matter (SOM) increased with SREs application, thereby generating a positive priming effect for CO2 and CH4 emissions. However, the priming effect for CO2 and CH4 emissions was reduced with increased amounts of N and P. Furthermore, the addition of SREs with increasing N and P significantly enhanced the microbial SREs-derived C-use efficiency. Structural equation models indicated that NH4+-N and Olsen P negatively influenced the priming effect, whereas the microbial biomass and enzyme stoichiometry positively influenced the priming effect. In conclusion, our data suggest that SREs combined with increasing amounts of N and P could meet microbial stoichiometric demands and regulate microbial activity, which finally inhibited the mineralisation of SREs-C and the priming effect on paddy soil and positively affected C sequestration.
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Oryza , Solo , Biomassa , Calcificação Fisiológica , Carbono , Microbiologia do SoloRESUMO
In this work, we demonstrate that zero-dimensional Au nanoparticles (0D Au NPs)-decorated three-dimensional bismuth oxyiodide (BiOI) nanoflower (3D BiOI NFs)/two-dimensional nickel oxide (NiO) nanosheet array (2D NiO NSAs) hybrid nanostructures can be used as a self-powered cathodic photoelectrochemical (PEC) biosensing platform. The in situ formation of 3D BiOI NFs on 2D NiO NSAs was carried out by a chemical bath deposition method, while 0D Au NPs were coated on 3D BiOI NFs/2D NiO NSAs through a dip-coating method. Subsequently, glucose oxidase (GOD) as an enzyme model was immobilized on the surface of a Au@BiOI/NiO electrode via the adhesion of poly-(diallyldimethylammonium chloride) (PDDA). The proposed heterostructure exhibited excellent PEC properties because the unique structure of the Au NPs@BiOI NFs/NiO NSAs increased the specific surface area, light harvesting ability and the surface plasmon resonance effect of the Au NPs. The system displayed high sensitivity toward glucose in the presence of an air-saturated electrolyte. At the optimum conditions, the biosensor showed a promising application for the self-powered cathodic PEC biosensing of glucose, with a dynamic linear range of 1 × 10-7 M to 5 × 10-2 M and a low limit of detection of 8.71 × 10-8 M. Moreover, the proposed self-powered PEC biosensor was evaluated for the determination of diluted glucose injections, with the results indicating the potential of the proposed biosensor for bioanalysis applications.
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Hexavalent chromium [Cr (VI)] is a well-known human carcinogen associated with the increased risk of lung cancer. However, the mechanism underlying the Cr (VI)-induced carcinogenesis remains unclear due to the lack of suitable experimental models. In this study, we developed an in vitro model by transforming nontumorigenic human lung epithelial BEAS-2B cells through long-term exposure to Cr (VI). By utilizing this model, we found that miR-143 expression levels were dramatically repressed in Cr (VI)-transformed cells. The repression of miR-143 led to Cr (VI)-induced cell malignant transformation and angiogenesis via upregulation of insulin-like growth factor-1 receptor (IGF-IR) and insulin receptor substrate-1 (IRS1) expression. Moreover, we found that interleukin-8 is the major upregulated angiogenesis factor induced by Cr (VI) through activation of IGF-IR/IRS1 axis followed by activation of downstream ERK/hypoxia-induced factor-1α/NF-κB signaling pathway. These findings establish a causal role and mechanism of miR-143 in regulating Cr (VI)-induced malignant transformation and tumor angiogenesis.
Assuntos
Carcinógenos Ambientais/toxicidade , Transformação Celular Neoplásica/efeitos dos fármacos , Cromo/toxicidade , Neoplasias Pulmonares/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Animais , Linhagem Celular , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Regulação para Baixo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Células Epiteliais/patologia , Humanos , Proteínas Substratos do Receptor de Insulina/biossíntese , Interleucina-8/biossíntese , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/imunologia , Neovascularização Patológica/metabolismo , Receptor IGF Tipo 1/biossíntese , Regulação para CimaRESUMO
Dysregulation of microRNAs is a common feature in human cancers, including breast cancer (BC). Here we describe the epigenetic regulation of miR-148a and miR-152 and their impact on BC cells. Due to the hypermethylation of CpG island, the expression levels of both miR-148a and miR-152 (miR-148a/152) are decreased in BC tissues and cells. DNMT1, the DNA methyltransferase 1 for the maintenance methylation, is aberrantly up-regulated in BC and its overexpression is responsible for hypermethylation of miR-148a and miR-152 promoters. Intriguingly, we found that DNMT1 expression, which is one of the targets of miR-148a/152, is inversely correlated with the expression levels of miR-148a/152 in BC tissues. Those results lead us to propose a negative feedback regulatory loop between miR-148a/152 and DNMT1 in BC. More importantly, we demonstrate that IGF-IR and IRS1, often overexpressed in BC, are two novel targets of miR-148a/152. Overexpression of miR-148a or miR-152 significantly inhibits BC cell proliferation, colony formation, and tumor angiogenesis via targeting IGF-IR and IRS1 and suppressing their downstream AKT and MAPK/ERK signaling pathways. Our results suggest a novel miR-148a/152-DNMT1 regulatory circuit and reveal that miR-148a and miR-152 act as tumor suppressors by targeting IGF-IR and IRS1, and that restoration of miR-148a/152 expression may provide a strategy for therapeutic application to treat BC patients.
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Transformação Celular Neoplásica/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Receptor IGF Tipo 1/genética , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Gradação de Tumores , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
MiR-145 is known as a tumor suppressor in numerous human cancers. However, its role in tumor angiogenesis remains poorly defined. In this study, we found that miR-145 was significantly downregulated in breast cancer tissues by using 106 cases of normal and cancer tissues as well as in breast cancer cells. MiR-145 exhibited inhibitory role in tumor angiogenesis, cell growth and invasion and tumor growth through the post-transcriptional regulation of the novel targets N-RAS and VEGF-A. In addition, we provide evidence that the expression levels of miR-145 correlate inversely with malignancy stages of breast tumors, although there is no association between miR-145 levels and hormone receptor levels in breast cancer. Taken together, these results demonstrate that miR-145 plays important inhibitory role in breast cancer malignancy by targeting N-RAS and VEGF-A, which may be potential therapeutic and diagnostic targets.
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MicroRNAs/metabolismo , Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas ras/metabolismo , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Regulação para Baixo , Feminino , Humanos , Camundongos , Transplante HeterólogoRESUMO
PURPOSE: To retrospectively analyze the relationships of peritoneal serum relative to venous serum (R (p/v)) ratios for human chorionic gonadotropin, CA-125, and creatine kinase to the ectopic pregnancy (EP). METHODS: Intra-abdominal fluid and venous blood samples of 118 subjects with suspected EP were obtained for biomarker measurements. R (p/v-hCG) >1 was considered indicative of EP, and final diagnosis was based on surgical finding of an ectopic chorionic villous or gynecological ultrasound finding of an intrauterine gestational sac. RESULTS: R (p/v-hCG) and R (p/v-CA-125) were both significantly greater for abortive as compared to ruptured EP and for the absence as compared to presence of active bleeding. However, neither ratio differed significantly between ampullary and isthmic EP. R (p/v-hCG) and R (p/v-CA-125) correlated negatively with hemoperitoneum volume. R (p/v-hCG) exhibited only modest predictive value for rupture. However, with R (p/v-CA-125) as the diagnostic criterion for rupture, sensitivity and specificity were 66.7 and 100%, respectively; in patients initially diagnosed with EP, R (p/v-CA-125) values <22.43 effectively predicted rupture. R (p/v-CK) did not exhibit significant diagnostic value. CONCLUSIONS: R (p/v-hCG) values >1 combined with positive culdocentesis test findings reliably indicate the presence of EP. In patients initially diagnosed with EP, R (p/v-CA-125) values <22.43 predict tubal rupture.
Assuntos
Gravidez Ectópica/sangue , Gravidez Ectópica/diagnóstico , Adulto , Biomarcadores/sangue , Antígeno Ca-125/sangue , Gonadotropina Coriônica/sangue , Vilosidades Coriônicas/diagnóstico por imagem , Vilosidades Coriônicas/cirurgia , Creatina Quinase/sangue , Feminino , Saco Gestacional/diagnóstico por imagem , Saco Gestacional/cirurgia , Humanos , Valor Preditivo dos Testes , Gravidez , Gravidez Ectópica/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia , Ruptura Uterina/sangue , Ruptura Uterina/diagnóstico , Ruptura Uterina/diagnóstico por imagem , Adulto JovemRESUMO
PURPOSE: To investigate expression, regulation, potential role and targets of miR-195 and miR-497 in breast cancer. EXPERIMENTAL DESIGN: The expression patterns of miR-195 and miR-497 were initially examined in breast cancer tissues and cell lines by Northern blotting and quantitative real-time PCR. Combined bisulfite restriction analysis and bisulfite sequencing were carried out to study the DNA methylation status of miR-195 and miR-497 genes. Breast cancer cells stably expressing miR-195 and miR-497 were established to study their role and targets. Finally, normal, fibroadenoma and breast cancer tissues were employed to analyze the correlation between miR-195/497 levels and malignant stages of breast tumor tissues. RESULTS: MiR-195 and miR-497 were significantly downregulated in breast cancer. The methylation state of CpG islands upstream of the miR-195/497 gene was found to be responsible for the downregulation of both miRNAs. Forced expression of miR-195 or miR-497 suppressed breast cancer cell proliferation and invasion. Raf-1 and Ccnd1 were identified as novel direct targets of miR-195 and miR-497. miR-195/497 expression levels in clinical specimens were found to be correlated inversely with malignancy of breast cancer. CONCLUSIONS: Our data imply that both miR-195 and miR-497 play important inhibitory roles in breast cancer malignancy and may be the potential therapeutic and diagnostic targets.
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Neoplasias da Mama/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Sequência de Bases , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ilhas de CpG , Ciclina D1/metabolismo , Metilação de DNA , Regulação para Baixo , Feminino , Inativação Gênica , Genes Reporter , Humanos , Luciferases de Renilla/biossíntese , Luciferases de Renilla/genética , MicroRNAs/metabolismo , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-raf/metabolismo , Mapeamento por RestriçãoRESUMO
MicroRNAs (miRNAs) are a class of endogenous, small non-protein coding single-stranded RNA molecules, which are crucial post-transcriptional regulators of gene expression. Previous studies have shown that miRNAs participate in a wide range of biological functions and play important roles in various human diseases including glioma. However, the role of miRNAs in mediating glioblastoma cell migration and invasion has not been elucidated. Using miRNA microarray, we identified miR-146b as one of the miRNAs that is significantly dysregulated in human glioblastoma tissue. We showed that miR-146b overexpression by transfection with the precursor miR-146b, or knock-down by Locked Nucleic Acid (LNA)-modified anti-miR-146b, has no effect on the growth of human glioblastoma U373 cells. However, precursor miR-146b transfection significantly reduced the migration and invasion of U373 cells, while LNA-anti-miR-146b transfection generated the opposite result. Furthermore, we discovered that a matrix metalloproteinase gene, MMP16, is one of the downstream targets of miR-146b. Taken together, our findings suggest that miR-146b is involved in glioma cell migration and invasion by targeting MMPs, and implicate miR-146b as a metastasis-inhibiting miRNA in glioma.
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Neoplasias Encefálicas/genética , Movimento Celular/genética , Glioma/genética , Metaloproteinase 16 da Matriz/genética , MicroRNAs/genética , Neoplasias Encefálicas/patologia , Divisão Celular/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioma/secundário , Humanos , Mutagênese Sítio-Dirigida , Invasividade Neoplásica , TransfecçãoRESUMO
MicroRNAs (miRNAs) are non-protein-coding RNAs that function as post-transcriptional gene regulators. Recent evidence has shown that miRNA plays a pivotal role in the development of many cancers including glioma, a lethal brain cancer. We have recently compared the miRNA expression profiles between normal brain and glioma tissues from Chinese patients by miRNA microarray and identified a panel of differentially expressed miRNAs. Here, we studied the function of one miRNA, miR-15b, in glioma carcinogenesis and elucidated its downstream targets. Over-expression of miR-15b resulted in cell cycle arrest at G0/G1 phase while suppression of miR-15b expression resulted in a decrease of cell populations in G0/G1 and a corresponding increase of cell populations in S phase. We further showed that CCNE1 (encoding cyclin E1) is one of the downstream targets of miR-15b. Taken together, our findings indicate that miR-15b regulates cell cycle progression in glioma cells by targeting cell cycle-related molecules.
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Neoplasias Encefálicas/patologia , Ciclo Celular/genética , Ciclinas/genética , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , MicroRNAs/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Glioma/genética , Humanos , MicroRNAs/genéticaRESUMO
Diethylnitrosamine (DEN) is a known carcinogen that can alkylate DNA molecules. In rats, DEN-induced hepatocellular carcinoma (HCC) model is well established. In this study, we used a two-dimensional differential gel electrophoresis (2D-DIGE) system and liquid chromatography/mass spectrometry/mass spectrometry to identify the differential expression protein profiles between the DEN-induced HCC and healthy liver cells. Western blotting and semiquantitative RT-PCR were used to further confirm the results. Seventeen differentially expressed spots were identified in DEN-induced HCC cells. Among all, the most prominent upregulated proteins include the members of the glutathione S-transferase super family, aldo-keto reductase superfamily and proteins involved in the response to oxidative stress. Downregulation was observed in 2 proteins that were known to contribute to hepatic dysfunction. This study provides the first comprehensive protein profiling of the DEN-induced HCC in rats. This model simulates the differential protein expression of human HCC and may be useful for further understanding the mechanism of HCC tumorigenesis.
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Carcinógenos/toxicidade , Dietilnitrosamina/toxicidade , Eletroforese em Gel Bidimensional/métodos , Neoplasias Hepáticas Experimentais/metabolismo , Animais , Sequência de Bases , Cromatografia Líquida , Primers do DNA , Glutationa/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas em TandemRESUMO
We report the preparation of a non-polymer coated superparamagnetic nanoparticle that is stable and biocompatible both in vitro and in vivo. The non-polymer, betaine, is a natural methylating agent in mammalian liver with active surface property. Upon systemic administration, the nanoparticle has preferential biodistribution in mammalian liver and exhibits good reduction of relaxivity time and negative enhancement for the detection of hepatoma nodules in rats using MRI. Our data demonstrate that the non-polymer coated superparamagnetic nanoparticle should have potential applications in biomedicine.