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Gliomas are commonly known as primary brain tumors and associated with frequent recurrence and an unsatisfactory prognosis despite extensive research in the underlying molecular mechanisms. We aimed to examine the role of ANTXR1 in glioma tumorigenesis and explore its downstream regulatory mechanism. ANTXR1 expression in clinical specimens and its relationship with some pathological characteristics were detected using immunohistochemical staining. After silencing/upregulating ANTXR1 through lentiviral transfection in glioma cell lines, qRT-PCR and western blotting were used to examine mRNA and protein levels, and cell phenotype was also detected. ANTXR1-knockdown and -overexpression cells were then processed by AKT activator and PI3K inhibitor, respectively, to verify downstream PI3K/AKT pathway regulated by ANTXR1. Xenograft nude mice models were constructed to verify the role of ANTXR1 in vivo. We found overexpression of ANTXR1 in both cell lines in comparison with those in normal brain tissues. Glioma cell growth and migratory ability were dramatically impaired as a result of silencing ANTXR1 by shANTXR1 lentiviruses. ANTXR1 blockade also accelerated cell apoptosis and held back cell cycle via targeting G2 phrase during cell mitosis. In vivo xenograft models verified in vitro findings above. Further exploration disclosed that AKT activator promoted anti-tumor effects mediated by ANTXR1 knockdown, while PI3K inhibitor limited pro-tumor effects mediated by ANTXR1 overexpression, indicating that ANTXR1 functioned in glioma cells through regulating PI3K/AKT pathway. ANTXR1 could play an indispensable role in glioma tumorigenesis via activating PI3K/AKT-mediated cell growth. Our study provides a theoretical basis for targeting ANTXR1 as a molecular target in glioma clinical therapeutics.
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Glioma , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Camundongos Nus , Glioma/patologia , Proliferação de Células/genética , Moléculas de Adesão Celular , Carcinogênese/genética , Linhagem Celular Tumoral , Apoptose/genética , Proteínas dos Microfilamentos/metabolismo , Receptores de Superfície CelularRESUMO
Rapid and sensitive detection of microRNAs is of great importance in biological researches and cancer diagnosis. Herein, we proposed a novel homogeneous electrochemical sensor to detect microRNA-21 (miRNA-21) using functionalized magnetic nanoparticles combined with enzyme-assisted signal amplification. The biotinylated capture probe (CP) labeled magnetic nanoparticles can capture miRNA-21 and introduce streptavidin-conjugated hydroxyapatite (HAP) nanoparticles. In the presence of miRNA-21, hybridization between RNA and DNA results in the formation of RNA/DNA duplexes, and then duplex-specific nuclease (DSN) cleave the duplexes to digest the capture chain and release the miRNA-21 in a loop. Meanwhile, the HAP nanoparticles strip from the magnetic nanoparticles and electrochemical signal by the reaction of HAP with molybdate is changed. The current variation before and after incubation with miRNA-21 is linearly correlated with the miRNA-21 concentration between 1 aM and 1 pM with a low detection limit (LOD) of 0.27 aM. Remarkably, the expression of miRNA-21 in human serum and different cell lysate was successfully performed, which fully demonstrates the great practical potentials in biomedical diagnostics and clinical therapeutics.
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Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Humanos , MicroRNAs/genética , Técnicas Biossensoriais/métodos , DNA , Hibridização de Ácido Nucleico , Limite de Detecção , Técnicas Eletroquímicas/métodosRESUMO
AIM OF THE STUDY: Aim of the study is To investigate the effect of lentinan on proliferation and apoptosis of human astrocytoma U251 cells. Lentinan was dissolved in DMEM complete medium to form different concentrations (0, 25, 50, 100, 200, 400, 500, 600 µg/ml). CCK8 was used to detect the effect of lentinan with different concentrations on proliferation of human astrocytoma U251 cells, and the expression of Ki-67 was detected by immunofluorescence. In addition, the effect of different concentrations of lentinan on apoptosis of human astrocytoma U251 cells was detected by flow cytometry. Compared with the blank control group, 50 and 100 µg/ml lentinan significantly promoted proliferation of human astrocytoma U251 cells. When the concentration is more than 100 µg/ml, the cell activity gradually decreases, and the cell activity is the lowest when the concentration is 600 µg/ml. In addition, the low concentration lentinan (25, 50, and 100 µg/ml) had no significant effect on apoptosis of human astrocytoma U251 cells. However, lentinan above 200 µg/ml significantly promoted apoptosis of human astrocytoma U251 cells and had a concentration gradient effect, and the highest apoptosis rate was at 600 µg/ml. CONCLUSIONS: Lentinan can effectively inhibit proliferation and promote apoptosis of human astrocytoma U251 cells.
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Astrocitoma , Lentinano , Humanos , Lentinano/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , ApoptoseRESUMO
Arsenic (As) biotransformation in soil affects As biogeochemical cycling and is associated with As accumulation in rice. After inoculation with 1% iron-oxidizing bacteria (FeOB) in paddy soil, As speciation, As biotransformation genes in soil, As/Fe in Fe plaques, and As accumulation in rice were characterized. Compared with the control, the available As concentrations in soils decreased while amorphous and poorly crystalline Fe-Al oxidized As and crystalline Fe-Al oxidized As fractions increased of F (FeOB) and RF (rice and FeOB) treatments. Fe concentrations increased and positively correlated with As concentrations in Fe plaques on the rice root surface (***P < 0.001). Compared with R (rice), Monomethyl As (MMA), dimethyl As (DMA), arsenate (As(V)), and arsenite (As(III)) concentrations in rice plants showed a downwards trend of RF treatment. The As concentration in grains was below the National Standard for Food Safety (GB 2762-2017). A total of 16 As biotransformation genes in rhizosphere soils of different treatments (CK, F, R and RF were quantified by high-throughput qPCR (HT-qPCR). Compared with the control, the As(V) reduction and As transport genes abundance in other treatments increased respectively by 54.54%-69.17% and 54.63%-73.71%; the As(III) oxidation and As (de) methylation genes did not change significantly; however, several As(III) oxidation genes (aoxA, aoxB, aoxS, and arsH) increased. These results revealed that FeOB could reduce, transport As, and maybe also oxidize As. In addition, As(III) oxidation gene (aoxC) in rhizosphere soil was more abundant than in non-rhizosphere soil. It indicated that radial oxygen loss (ROL) promoted As(III) oxidation in rhizosphere soils. The results provide evidence for As biotransformation by ROL and FeOB in soil-rice system. ROL affects As oxidation and immobilization, and FeOB affects As reduction, transportation and may also affect As oxidation.
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Arsênio , Arsenitos , Ochrobactrum , Oryza , Poluentes do Solo , Arsênio/análise , Solo/química , Oryza/metabolismo , Arseniatos/metabolismo , Arsenitos/metabolismo , Ferro/química , Poluentes do Solo/análise , Raízes de Plantas/metabolismo , Biotransformação , Oxirredução , Oxigênio/análiseRESUMO
Iron-oxidizing strain (FeOB) and iron modified biochars have been shown arsenic (As) remediation ability in the environment. However, due to the complicated soil environment, few field experiment has been conducted. The study was conducted to investigate the potential of iron modified biochar (BC-FeOS) and biomineralization by a new found FeOB to remediate As-contaminated paddy field. Compared with the control, the As contents of GB (BC-FeOS), GF (FeOB), GFN (FeOB and nitrogen fertilizer), GBF (BC-FeOS and FeOB) and GBFN (BC-FeOS, FeOB and nitrogen fertilizer) treatments in pore water decreased by 36.53%-80.03% and the microbial richness of iron-oxidizing bacteria in these treatments increased in soils at the rice maturation stage. The concentrations of available As of GB, GF, GFN, GBF and GBFN at the tillering stage were significantly decreased by 10.78%-55.48%. The concentrations of nonspecifically absorbed and specifically absorbed As fractions of GB, GF, GFN, GBF and GBFN in soils were decreased and the amorphous and poorly crystalline hydrated Fe and Al oxide-bound fraction was increased. Moreover, the As contents of GB, GF, GFN, GBF and GBFN in rice grains were significantly decreased (*P < 0.05) and the total As contents of GFN, GBF and GBFN were lower than the standard limit of the National Standard for Food Safety (GB 2762-2017). Compared with the other treatments, GBFN showed the greatest potential for the effective remediation of As-contaminated paddy fields.
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Arsênio , Ochrobactrum , Oryza , Poluentes do Solo , Arsênio/análise , Carvão Vegetal , Ferro/análise , Oxirredução , Solo , Poluentes do Solo/análiseRESUMO
Nickel iron hydroxides (NiFeOH) have been drawing enormous attention as effective catalysts for oxygen evolution reaction (OER), a key process in water splitting. Herein, we report that negatively charged iron(III) hydroxide colloidal particles, can significantly enhance the OER activity of NiFeOH in alkaline media. NiFeOH is grown on nickel foam in a supersaturated iron(III) salt solution, which also contains a high content of Fe(OH)3 colloidal nanoparticles, forming free-standing NiFeOH@Cx electrodes (with x being the Fe(OH)3 concentration). The interface between NiFeOH and Fe(OH)3 colloidal particles, as manifested by the unique volcano-like holes on the NiFeOH@Cx surface, is likely the OER active sites. In comparison to Fe(OH)3-free NiFeOH, NiFeOH@C1000 exhibits a 40-fold enhancement of the OER activity, confirming the significant effect of Fe(OH)3 colloidal nanoparticles in boosting the OER activity, likely as a result of enhanced charge transfer from Ni2+ to Fe3+ that facilitates the adsorption of key reaction intermediates. Furthermore, by coupling the free-standing NiFeOH@C1000 electrode with commercial Pt/C, full water splitting can occur and reach a current density of 10 mA cm-2 under a cell voltage of 1.51 V, which is lower than that (1.59 V) based on noble metal catalysts of RuO2 + Pt/C.
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Deep-ultraviolet (deep-UV) nonlinear optical (NLO) crystals are key materials in creating tunable deep-UV lasers for frequency conversion technology. However, practical application of the sole usable crystal, KBe2 BO3 F2 , has been hindered by the high toxicity of beryllium and its layering tendency in crystal growth. Herein, we report a beryllium-free deep-UV NLO material NaSr3 (OH)(B9 O16 )[B(OH)4 ] (NSBOH), synthesized by a covalent bond modification strategy under hydrothermal conditions. Moisture-stable NSBOH exhibits strong second-harmonic generation (SHG) at 1064â nm (3.3 × KH2 PO4 ) and 532â nm (0.55 × ß-BaB2 O4 ), both amongst the largest powder SHG responses for a deep-UV borate, with good phase-matchability and a short wavelength cutoff edge (below 190â nm). NSBOH possesses a 3D covalent anionic [B9 O19 ]∞ honeycomb-like framework with no layering. The Sr2+ and Na+ ions, residing in the cavities of the anionic framework, act as templates for the assembly and favorable alignment of NLO-active groups, resulting in an optimal balance between strong SHG activities and wide UV transparency. These merits indicate NSBOH is a very attractive candidate for deep-UV NLO applications.
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OBJECTIVES: Glioblastoma (GBM) represents the commonest malignant glioma. Long non-coding RNA (lncRNA) FEZ family zinc finger 1 antisense RNA 1 (FEZF1-AS1) has been validated to play an oncogenic role in multiple human malignancies, while its function in GBM has not been largely reported. We aim to identify the regulatory mechanism of FEZF1-AS1 in GBM. MATERIALS & METHODS: The expression pattern of FEZF1-AS1 was firstly figured out in GBM cells using RT-qPCR. Then, functional assays were conducted to examine the influence FEZF1-AS1 had on the biological properties of GBM cells. The downstream targets of FEZF1-AS1 were predicted and the underlying regulatory mechanism was determined by mechanism assays. RESULTS: FEZF1-AS1 possessed high expression in GBM cells. Down-regulation of FEZF1-AS1 suppressed GBM cell proliferation, migration and invasion while inducing cell apoptosis. With the help of bioinformatics prediction and mechanism assays, FEZF1-AS1 was found to bind to miR-363-3p and NOB1 was determined to be the downstream gene. Finally, results of rescue assays verified that the suppressive function of FEZF1-AS1 inhibition on GBM development were restored by miR-363-3p depletion or overexpression of NOB1. CONCLUSION: FEZF1-AS1 had oncogenic function in the advancement of GBM by targeting miR-363-3p/NOB1, which made FEZF1-AS1 a potential biomarker for GBM treatment.
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Neoplasias Encefálicas/genética , Glioblastoma/genética , MicroRNAs/metabolismo , Proteínas Nucleares/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Humanos , Regulação para CimaRESUMO
BACKGROUND: PYD and CARD domain-containing (PYCARD) was upregulated in TMZ-resistant cell lines and glioma tissue and was correlated with poor prognosis, its role in glioma is unclear known. The aim of this study was to elucidate the relationship between PYCARD and glioma based on Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and Chinese Glioma Genome Atlas (CGGA) databases. METHODS: Glioma-resistant cells were compared with parental cells based on the GSE53014 and GSE113510 data sets. The relationship between PYCARD, tumor microenvironment, and long noncoding RNAs (lncRNAs) was assessed using logistic regression. Moreover, Kaplan-Meier and Cox regression were used to analyze the relationship between PYCARD expression and survival rate. Gene set enrichment analysis (GSEA) was also used to determine the biological function of PYCARD and lncRNAs. Cell viability and cell migration assays were used to evaluate the ability of cells to migrate and proliferate. Finally, we analyzed the expression patterns of PYCARD genes in a wide range of cancers. RESULTS: Elevated expression of PYCARD promoted glioma cell proliferation and migration. PYCARD expression was significantly positively associated with gamma delta T cells but negatively correlated with M2 macrophages in glioblastoma multiforme (GBM). Likewise, PYCARD expression was significantly positively associated with monocytes but negatively associated with activated mast cells in low grade glioma (LGG). We also found that 3 PYCARD-related lncRNAs in GBM and 4 PYCARD-related lncRNAs in LGG had a predictive value for glioma patients. The pan-cancer analysis showed that PYCARD expression was higher in most cancer groups. CONCLUSIONS: High expression of PYCARD is an independent predictor of unfavorable prognosis and chemotherapy resistance in glioma.
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BACKGROUND: There lacks an ideal model for accurately predicting clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreatoduodenectomy (PD). This study aimed at developing a nomogram with high accuracy in predicting CR-POPF after PD. METHODS: A total of 1182 patients undergoing PD in the First Affiliated Hospital of Sun Yat-sen University (FAHSYSU, n = 762) and Fudan University Shanghai Cancer Center (FUSCC, n = 420) between January 2010 and May 2018 were enrolled. The patients from FAHSYSU were assigned as testing cohort, and those from FUSCC were used as external validation cohort. Univariate and multivariate logistic regression analyses were performed to determine the predictive factors for CR-POPF. Nomogram was developed on the basis of significant predictors. The performance of nomogram was evaluated by area under receiver operating characteristic (ROC) curve (AUC), calibration curve, and decision curve analysis. RESULTS: In testing cohort, 87 out of 762 patients developed CR-POPF. Three predictors were significantly associated with CR-POPF, including body mass index ≥24.0 kg/m2, pancreatic duct diameter <3 mm, and drainage fluid amylase on postoperative day 1 ≥2484 units/L (all p ≤ 0.001). Prediction of nomogram was accurate with AUC of 0.934 (95% confidence interval [CI]: 0.914-0.950) in testing cohort and 0.744 (95% CI: 0.699-0.785) in external validation cohort. The predictive accuracy of nomogram was better than that of previously proposed fistula risk scores both in testing and external validation cohort (all p < 0.05). CONCLUSIONS: The novel nomogram based on three easily available parameters could accurately predict CR-POPF after PD. It would have high clinical value due to its accuracy and convenience.
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Fístula Pancreática , Pancreaticoduodenectomia , China , Humanos , Nomogramas , Pâncreas/cirurgia , Fístula Pancreática/diagnóstico , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Fatores de RiscoRESUMO
Glioblastoma (GBM) is an invasive cancer with poor prognosis in patients. Researching on molecular functions in GBM has attracted more and more attention. Actin gamma 1 (ACTG1) was reported as a pathogenic gene in skin cancer and colorectal cancer. Present study was designed to explore the biological role and underlying mechanism of ACTG1 in GBM cells. It was uncovered that ACTG1 presented high expression trends in GBM cells. Moreover, ACTG1 suppression hindered cell proliferation and boosted cell apoptosis in GBM. Then, according to the results of bioinformatics analysis and mechanism assays including RIP, RNA pull down and luciferase reporter assay, ACTG1 was verified to be targeted by miR-361-5p in GBM. Next, COX10-AS1 (COX10 antisense RNA 1) was identified as an endogenous sponge for miR-361-5p in GBM. Moreover, COX10-AS1 acted as a competing endogenous RNA (ceRNA) to positively regulate ACTG1 expression via sponging miR-361-5p. The following rescue assays demonstrated that COX10-AS1 promoted GBM cell proliferation and inhibited GBM cell apoptosis through ACTG1 up-regulation at a miR-361-5p dependent way. On the whole, present study uncovered a novel ceRNA pattern in which COX10-AS1 sponged miR-361-5p to elevate ACTG1 expression, therefore accelerating tumorigenesis in GBM. The findings suggested new promising targets for GBM treatment.
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Alquil e Aril Transferases/genética , Apoptose/fisiologia , Proliferação de Células/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Glioblastoma/metabolismo , Proteínas de Membrana/genética , RNA Antissenso/metabolismo , Actinas/metabolismo , Linhagem Celular Tumoral , Humanos , MicroRNAs/metabolismo , Regulação para Cima/fisiologiaRESUMO
Gold nanoparticle (AuNP)-anchored BP nanosheets were synthesized through in situ growth of AuNPs onto BP. Due to the strong chelating ability of P or phosphorus oxides with AuNPs, the stability of BP is improved. As proof-of-concept demonstration of the functionalized BP, electrochemical detection of circulating tumor cells (CTCs) based on BP@AuNPs@aptamer as a probe combined with immunomagnetic separation is reported. The aptamer can specifically bind with CTCs, while the phosphorus oxides including phosphite ion and phosphate ion (PxOy species) on BP and aptamer can react with molybdate to generate an electrochemical current, leading to dual signal amplification. The biosensor is applied to MCF-7 cell detection and displays good analytical performance with a detection limit of 2 cell mL-1. Furthermore, the practicality of this biosensor was validated through sensitive determination of MCF-7 cells in human blood. Therefore, the reported biosensor could be applied to detect other biomarkers, offering an ultrasensitive strategy for clinical diagnostics. Graphical abstract Electrochemical detection of circulating tumor cells based on gold nanoparticle-modified black phosphorus nanosheets is reported.
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Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Separação Imunomagnética/métodos , Nanopartículas Metálicas/química , Células Neoplásicas Circulantes/química , Fósforo/química , Anticorpos Imobilizados/imunologia , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/imunologia , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Limite de Detecção , Molibdênio/química , Mucina-1/química , Células Neoplásicas Circulantes/imunologia , Estudo de Prova de Conceito , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CC) is a rare subtype of primary liver cancers. Its prognostic factors remain unclear. The study aimed to evaluate its long-term outcome and prognostic factors by retrospectively reviewing the series of cHCC-CC after curative resection from our institute. METHODS: A total of 55 pathologically confirmed cHCC-CC patients undergoing curative resections between January 2003 and January 2018 at the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) were included. The clinicopathological and follow-up data were retrieved. Overall survival (OS) and recurrence-free survivals (RFS) were analysed by Kaplan-Meier curve. The independent prognostic factors were determined by using univariate and multivariate Cox analyses. RESULTS: There were 41 males and 14 females, with a median age of 51.0 (interquartile range, 44.0-60.0) years. The 1-, 3-, and 5-year OS and RFS rates in cHCC-CC were 80.0%, 25.5%, and 16.4%, respectively, and 52.7%, 21.8%, and 10.9%, respectively. The median OS and RFS were 24.9 and 14.5 months, respectively. Univariate and multivariate analyses revealed that elevated alpha-fetal protein (AFP) and/or CA19-9, vascular invasion, local extra-hepatic invasion, and lymph-node metastasis (LNM) were independent unfavorable prognostic factors for OS and RFS (all P < 0.005). Furthermore, elevated AFP and/or CA19-9 were independent unfavorable prognostic factors in various subgroups of cHCC-CC, including patients aged <60 years, positive hepatitis B surface antigen, cirrhosis, single tumor, tumor size ≥5 cm, no vascular invasion, no LNM, and no local extra-hepatic invasion (all P < 0.05). CONCLUSIONS: Elevated AFP and/or CA19-9, vascular invasion, local extra-hepatic invasion, and LNM were independent unfavorable prognostic factors for long-term survival of cHCC-CC undergoing curative resections. Patients with normal levels of AFP and CA19-9 had better prognosis.
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The microbe-driven iron cycle plays an important role in speciation transformation and migration of arsenic (As) in soil-rice systems. In this study, pot experiments were used to investigate the effect of bacterial iron (Fe) reduction processes in soils on As speciation and migration, as well as on As uptake in soil-rice system. During the rice growth period, pH and electrical conductivity (EC) in soil solutions initially increased and then decreased, with the ranges of 7.4-8.8 and 116.3-820 mS cm-1, respectively. The concentrations of Fe, total As and As(III) showed an increasing trend in the rhizosphere and non-rhizosphere soil solutions with the increasing time. Fe concentrations were significantly positively correlated with total As and As(III) concentrations (***p < 0.001) in the soil solutions. The abundances of the arsenate reductase gene (arsC) and the As(III) S-adenosylmethionine methyltransferase gene (arsM) in rhizosphere soils were higher than those in non-rhizosphere soils, while the abundance of the Fe-reducing bacteria (Geo) showed an opposite trend. Moreover, it showed that the Geo abundance was significantly positively correlated with that of the arsC (***p < 0.001) and arsM (**p < 0.01) genes, respectively. The abundances of Geo, arsC and arsM genes were significantly positively correlated with the concentrations of Fe, total As and As(III) in the soil solutions (*p < 0.05). Moreover, the abundances of arsC and arsM genes were significantly negatively correlated with total As and As(III) in rice grains (*P < 0.05). These results showed that the interaction of bacterial Fe reduction process and radial oxygen loss from roots promoted the reduction and methylation of As, and then decreased As uptake by rice, which provided a theoretical basis for alleviating As pollution in paddy soils.
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Arsênio , Oryza , Poluentes do Solo , Ferro , Raízes de Plantas , SoloRESUMO
This work presents the first example of utilization of amphiphilic block copolymer PCL-PEG-PCL as a stationary phase for capillary gas chromatographic (GC) separations. The PCL-PEG-PCL capillary column fabricated by static coating provides a high column efficiency of 3951 plates/m for n-dodecane at 120 °C. McReynolds constants and Abraham system constants were also determined in order to evaluate the polarity and possible molecular interactions of the PCL-PEG-PCL stationary phase. Its selectivity and resolving capability were investigated by using a complex mixture covering analytes of diverse types and positional, structural, and cis-/trans-isomers. Impressively, it exhibits high resolution performance for aliphatic and aromatic isomers with diverse polarity, including those critical isomers such as butanol, dichlorobenzene, dimethylnaphthalene, xylenol, dichlorobenzaldehyde, and toluidine. Moreover, it was applied for the determination of isomer impurities in real samples, suggesting its potential for practical use. The superior separation performance demonstrates the potential of PCL-PEG-PCL and related block copolymers as stationary phases in GC and other separation technologies.
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Cromatografia Gasosa/métodos , Poliésteres/química , Polietilenoglicóis/química , Tensoativos/química , Varredura Diferencial de Calorimetria , Isomerismo , Temperatura , TermogravimetriaRESUMO
Cadmium contamination in paddy soils has aroused increasing concern around the world, and biochar has many positive properties, such as large specific surface areas, micro porous structure for the heavy metal immobilization in soils. However there are few studies on sulfur-iron modified biochar as well as its microbiology effects. The purpose of this study was to evaluate the Cd immobilization effects of sulfur or sulfur-iron modified biochar and its related microbial community changes in Cd-contaminated soils. SEM-EDX analysis confirmed that sulfur and iron were loaded on the raw biochar successfully. Sulfur-modified biochar (S-BC) and sulfur-iron modified biochar (SF-BC) addition increased pH value and the content of soil organic matter, and also decreased DTPA-extractable Cd. There was a negative significant correlation between organic matter content and the available Cd (Pâ¯<â¯0.05). During a 45-d incubation period, the fractions of Cd are mainly with the exchangeable (25.16-35.79%) and carbonate (22.01-25.10%) fractions. Compared with the control, the concentrations of exchangeable Cd in soil were significantly (Pâ¯<â¯0.05) decreased by 12.54%, 29.71%, 18.53% under the treatments of BC, S-BC, SF-BC respectively. The S-BC and SF-BC treatments significantly (Pâ¯<â¯0.05) increased Chao1, observed, Shannon and Simpson diversity indices compared with the control and biochar treatments. Meanwhile, the relative abundance of Proteobacteria, Bacteroidetes, and Actinobacteria increased, whereas the abundance of Acidobacteria and Germmatimonadetes decreased. Capsule: Sulfur-modified and sulfur-iron modified biochar applications decreased the available Cd and changed the microbial community.
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Cádmio/química , Carvão Vegetal/química , Microbiologia do Solo , Poluentes do Solo/química , Solo/química , Cádmio/análise , Ferro/química , Poluentes do Solo/análise , Enxofre/químicaRESUMO
This work presents the separation performance of star-poly(ε-caprolactone) (star-PCL) as the stationary phase for capillary gas chromatography (GC). The statically coated star-PCL column showed a column efficiency of 3345 plates per m and moderate polarity. Importantly, the star-PCL column exhibited high selectivity and resolving capability for more than a dozen mixtures covering a wide-ranging variety of analytes and isomers. Among them, the star-PCL column displayed advantageous resolving capability over the commercial DB-1701 column for aromatic amine isomers such as toluidine, chloroaniline and bromoaniline. Moreover, it was applied for the determination of isomer impurities in real samples, showing good potential in GC applications.
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This work presents the first example of the utilization of p-tert-butyl(tetradecyloxy)calix[6]arene (C6A-C10) as a stationary phase for capillary gas chromatographic (GC) separation. The statically coated C6A-C10 column showed a column efficiency of 3293 plates per m and had a nonpolar nature. Its selectivity and retention behaviour were investigated using a number of mixtures of diverse analytes and their isomers. As a result, the C6A-C10 column exhibited high resolving capability for aliphatic and aromatic analytes from apolar to polar nature, especially for positional, structural and cis-/trans-isomers. Moreover, the C6A-C10 column showed thermal stability up to 240 °C. In addition, it was applied for the determination of isomer impurities in real samples, proving its good potential for practical GC analysis.
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Arsenic contamination in paddy soils has aroused global concern due to its threats to food security and human health. Biochar modified with different iron materials was prepared for arsenic (As) immobilization in contaminated soils. Soil incubation experiments were carried to investigate the effects of biochar modified with Fe-oxyhydroxy sulfate (Biochar-FeOS), FeCl3 (Biochar-FeCl3), and zero-valent iron (Biochar-Fe) on the pH, NaHCO3-extractable As concentrations, and the As fractions in soils. The scanning electron microscope and X-ray diffraction analysis demonstrated that iron was successfully loaded onto the surface or embedded into the pores of the biochar. Addition of Biochar-FeOS, Biochar-FeCl3, and Biochar-Fe had no significant effects on the soil pH but significantly decreased the contents of NaHCO3-extractable As in soils by 13.95-30.35%, 10.97-28.39%, and 17.98-35.18%, respectively. Biochar-FeOS, Biochar-FeCl3, and Biochar-Fe treatments decreased the concentrations of non-specifically sorbed and specifically sorbed As fractions in soils, and increased the amorphous and poorly crystalline, hydrated Fe, Al oxide-bound, and residual As fractions. Compared with the other iron-modified biochars, Biochar-FeOS showed the most effective immobilization and has the potential for the remediation of As-contaminated paddy soils.
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Arsênio/química , Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Ferro/química , Poluentes do Solo/química , Poluição Ambiental/análise , Compostos Orgânicos , Óxidos/química , Solo/químicaRESUMO
A new strategy is proposed to fabricate adaptable protein-based hydrogel networks with both injectable and self-healable properties. By mixing proteins and metal ions under alkaline conditions, the metal ions can crosslink proteins into protein-metal ion dynamic networks. Subsequently, the metal ions can react with the cysteine residues of protein to in situ form corresponding metal sulfide NPs with ultra-small size, which leads to nanocomposite hydrogels with adaptable structures. This approach is general and a series of metal sulfide NP in situ embedded nanocomposite hydrogels were obtained. As an example, a Bi2 S3 -BSA hydrogel with tunable networks is shown to serve as an injectable, self-healable photothermal agent for the treatment of tumors. Our finding paves a new avenue for the preparation of injectable and self-healable hydrogels with potential applications in biomedicine.