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1.
Mol Carcinog ; 63(8): 1559-1571, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38780126

RESUMO

The therapeutic effect of anlotinib on neuroblastoma is still not fully understood. This study aims to explore the differentiation therapeutic effects of anlotinib on neuroblastoma and its potential association with the neural development regulatory protein collapsin response mediator protein 5 (CRMP5), both in vivo and in vitro. A patient-derived xenograft (PDX) model was established to observe the therapeutic effect of anlotinib. Neuroblastoma cell lines SK-N-SH and SK-N-AS were cultured to observe the morphological impact of anlotinib. Transwell assay was used to evaluate the cell invasion, and Western blot analysis and immunohistochemistry were employed to detect the expressions of neuronal differentiation-related proteins. Results indicate that anlotinib effectively inhibited tumor growth in the PDX model, modulated the expressions of neuronal differentiation markers. In vitro, anlotinib treatment induced neurite outgrowth in neuroblastoma cells and inhibited their invasive ability, reflecting a change in neuronal marker expression patterns consistent with the PDX model. Similarly, in the SK-N-AS mouse xenograft model, anlotinib demonstrated comparable tumor-suppressing effects and promoted neuronal-like differentiation. Additionally, anlotinib significantly downregulated CRMP5 expression in neuroblastoma both in vivo and in vitro. Overexpression of CRMP5 significantly reversed the differentiation therapy effect of anlotinib, exacerbating the aggressiveness and reducing the differentiation level of neuroblastoma. These findings highlight the potential of anlotinib as an anti-neuroblastoma agent. It may suppress tumor proliferation and invasion by promoting the differentiation of tumor cells towards a neuronal-like state, and this differentiation therapy effect involves the inhibition of CRMP5 signaling.


Assuntos
Diferenciação Celular , Proliferação de Células , Indóis , Proteínas do Tecido Nervoso , Neuroblastoma , Quinolinas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Neuroblastoma/metabolismo , Neuroblastoma/genética , Animais , Camundongos , Quinolinas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Indóis/farmacologia , Linhagem Celular Tumoral , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Camundongos Nus , Hidrolases/genética , Hidrolases/metabolismo , Antineoplásicos/farmacologia , Proteínas Associadas aos Microtúbulos
2.
J Neuroeng Rehabil ; 21(1): 38, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509563

RESUMO

BACKGROUND: Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation technique, has the potential to activate neurons in deep brain regions. The objective of this study was to evaluate the effects of repetitive TI stimulation targeting the lower limb motor control area (i.e., the M1 leg area) on lower limb motor function in healthy individuals, which could provide evidence for further translational application of non-invasive deep brain stimulation. METHODS: In this randomized, double-blinded, parallel-controlled trial, 46 healthy male adults were randomly divided into the TI or sham group. The TI group received 2 mA (peak-to-peak) TI stimulation targeting the M1 leg area with a 20 Hz frequency difference (2 kHz and 2.02 kHz). Stimulation parameters of the sham group were consistent with those of the TI group but the current input lasted only 1 min (30 s ramp-up and ramp-down). Both groups received stimulation twice daily for five consecutive days. The vertical jump test (countermovement jump [CMJ], squat jump [SJ], and continuous jump [CJ]) and Y-balance test were performed before and after the total intervention session. Two-way repeated measures ANOVA (group × time) was performed to evaluate the effects of TI stimulation on lower limb motor function. RESULTS: Forty participants completed all scheduled study visits. Two-way repeated measures ANOVA showed significant group × time interaction effects for CMJ height (F = 8.858, p = 0.005) and SJ height (F = 6.523, p = 0.015). The interaction effect of the average CJ height of the first 15 s was marginally significant (F = 3.550, p = 0.067). However, there was no significant interaction effect on the Y balance (p > 0.05). Further within-group comparisons showed a significant post-intervention increase in the height of the CMJ (p = 0.004), SJ (p = 0.010) and the average CJ height of the first 15 s (p = 0.004) in the TI group. CONCLUSION: Repetitive TI stimulation targeting the lower limb motor control area effectively increased vertical jump height in healthy adult males but had no significant effect on dynamic postural stability.


Assuntos
Extremidade Inferior , Músculo Esquelético , Adulto , Humanos , Masculino , Músculo Esquelético/fisiologia , Projetos de Pesquisa
3.
Drug Dev Res ; 85(1): e22140, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38349263

RESUMO

Everolimus, a known inhibitor of the mammalian target of rapamycin (mTOR), has shown uncertain efficacy in treating hepatoblastoma. This study delves into the potential anti-hepatoblastoma properties of everolimus and its intricate relationship with autophagy and ferroptosis, both in vitro and in vivo. In vivo, tumor tissue from hepatoblastoma patient and human hepatoblastoma cell line HuH-6 were xenografted into nude mice to establish xenograft models for observing the effect of everolimus on tumor growth. In vitro, HuH-6 cells were cultured to evaluate the anti-hepatoblastoma activity of everolimus. Transmission electron microscopy and microtubule-associated proteins 1 light chain 3 (LC3), beclin 1, and p62 protein expressions were employed to investigate autophagy. Additionally, indicators of cell apoptosis, reactive oxygen species (ROS) and proteins associated with ferroptosis were measured to evaluate ferroptosis. The results demonstrate that everolimus treatment effectively induced the formation of autophagosomes in hepatoblastoma cells, upregulated the LC3II/I ratio and beclin 1 expression, and downregulated p62 expression, indicating an enhanced autophagy level both in vitro and in vivo. Furthermore, everolimus treatment induced cell apoptosis, increased ROS level, elevated concentrations of malondialdehyde, 4-hydroxynonenal, and iron content, while reducing the ratio of glutathione/oxidized glutathione, and downregulating the protein expression of glutathione peroxidase 4 and solute carrier family 7 member 11, suggesting its ability to induce ferroptosis in hepatoblastoma cells. Importantly, the induction of ferroptosis by everolimus was significantly reversed in the presence of autophinib, an autophagy inhibitor, indicating the autophagy-dependent of everolimus-induced ferroptosis. Taken together, these findings suggest that everolimus holds promise as an effective anti-hepatoblastoma drug, with its mechanism of action potentially involving the induction of autophagy-dependent ferroptosis in hepatoblastoma cells.


Assuntos
Ferroptose , Hepatoblastoma , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Everolimo/farmacologia , Hepatoblastoma/tratamento farmacológico , Proteína Beclina-1 , Camundongos Nus , Espécies Reativas de Oxigênio , Autofagia , Neoplasias Hepáticas/tratamento farmacológico , Mamíferos
4.
Bioorg Chem ; 131: 106319, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36586300

RESUMO

Hypochlorite (ClO-) plays an important role in the human immune defense system, but high concentrations of ClO- in the endoplasmic reticulum (ER) damage cellular proteins, causing ER stress, cell death, and various diseases. Herein, we developed a simple hydrazone probe (1) featuring aggregation-induced ratiometric emission, which would quickly (within 20 s) and sensitively (detection limit of 15.4 µM) respond to ClO- in an almost pure aqueous solution via a fluorescent ratiometric output. Furthermore, the probe was employed to track the level of ClO- in the ER of HeLa cells and zebrafish.


Assuntos
Retículo Endoplasmático , Corantes Fluorescentes , Ácido Hipocloroso , Animais , Humanos , Retículo Endoplasmático/metabolismo , Corantes Fluorescentes/química , Células HeLa , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Peixe-Zebra/metabolismo
5.
Ecotoxicol Environ Saf ; 257: 114928, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37094485

RESUMO

Pig manure could be an effective fertilizer source for soil, but with high concentrations of xic elements. It has been shown that the pyrolysis method could largely reduce the environmental risk of pig manure. However, the comprehensive analysis of both toxic metals immobilization effect and environmental risk of pig manure biochar applied as a soil amendment is rarely addressed. To address the knowledge gap, this study was carried out with pig manure (PM) and pig manure biochar (PMB). The PM was pyrolyzed at 450 â„ƒ and 700 â„ƒ, the corresponding biochar was abbreviated as PMB450 and PMB700, respectively. The PM and PMB were applied in a pot experiment growing Chinese cabbage (Brassica rape L. ssp. Pekinensis) with clay-loam paddy soil. The application rates of PM were set at 0.5% (S), 2% (L), 4% (M) and 6% (H). With the equivalent mass principle, PMB450 and PMB700 were applied at 0.23% (S), 0.92% (L), 1.84% (M), 2.76% (H), and 0.192% (S), 0.7% (L), 1.4% (M), 2.1% (H), respectively. Parameters of Chinese cabbage biomass and quality, total and available concentrations of toxic metals in soil, and soil chemical properties were systemically measured. The main results of this study showed that compared with PM, PMB700 was more effective than PMB450, which induced the highest reductions of Cu, Zn, Pb, and Cd contents in cabbage by 62.6%, 73.0%, 43.9%, and 74.3%, respectively. Both PM and PMB increased the total contents of metals (Cu, Zn, Pb, and Cd) in soil, and PMB decreased the mobility of Cu, Zn, Pb, and Cd at high application rates (≥2%). Treatment with H-PMB700 reduced CaCl2 extractable Cu, Zn, Pb, and Cd by 70.0%, 71.6%, 23.3%, and 15.9%, respectively. For Cu, Zn, Pb, and Cd fractions with BCR extraction, PMB treatments, especially PMB700, were more effective than PM in decreasing the available fractions (F1 +F2 +F3) at high application rates (≥2%). Overall, pyrolysis with high temperature (e.g., 700 â„ƒ) could significantly stabilize the toxic elements in PM and enhance PM's effect on toxic metals immobilization. The marked effects of PMB700 on toxic metal immobilization and cabbage quality improvement might be attributed to high ash contents and liming effect.


Assuntos
Brassica , Metais Pesados , Poluentes do Solo , Suínos , Animais , Metais Pesados/análise , Cádmio/análise , Esterco/análise , Chumbo/análise , Poluentes do Solo/análise , Carvão Vegetal/química , Solo/química
6.
J Environ Manage ; 329: 117049, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563442

RESUMO

N-doping for the preparation of functional carbon materials is a trending research topic. In this study, N-rich biochar (BC) was prepared by calcining naturally N rich shrimp shells under oxygen-limiting environment, and the calcining temperatures were controlled. BC were activated with 5% hydrochloric acid solutions and then post-modified with ball-milling to obtain a series of novel adsorbents (MBCs). All samples were characterized by SEM, BET, FT-IR, XRD, XPS, TG, and element analysis. Surface area, pore volume, and other surface functional groups were significantly improved after acidizing and ball-milling. The adsorption capacities for MB were MBC350 > MBC500 > MBC650 >BC350 > BC650 > BC500, and the equilibrium adsorption capacities were 575.01 mg/g, 506.52 mg/g, 424.59 mg/g, 113.31 mg/g, 93.53 mg/g and 86.25 mg/g, respectively. The excellent adsorption performance of MBCs for MB was ascribed to Lewis acid-base interaction, π-π interaction, electrostatic interaction and van der Waals, and the quinone group and pyridinic-N on the surface of the MBCs are identified as the major active sites. Taken together, ball-milled shrimp shell biochar is a promising material for cation dye adsorption.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Azul de Metileno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Carvão Vegetal/química , Carbono , Adsorção , Poluentes Químicos da Água/química , Cinética
7.
Exp Cell Res ; 405(1): 112646, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34029571

RESUMO

The deubiquitinating enzyme USP46 (ubiquitin-specific protease 46) is implicated in various cancers. However, its role and regulatory mechanism in HCC (hepatocellular carcinoma) are still unknown. In this study, we showed that USP46 is downregulated in HCC tissues and that low USP46 levels are associated with poor prognosis in HCC patients. In functional experiments, overexpression of USP46 impaired proliferation and metastasis of HCC cells, whereas knockdown of USP46 enhanced cell proliferation and invasiveness in vitro and in vivo. Furthermore, we found that USP46 suppresses HCC cell proliferation and metastasis by inhibiting YAP1. Ectopic expression of YAP1 rescued the inhibition of cell proliferation and metastasis caused by USP46 overexpression. Mechanistically, USP46 promotes the degradation of YAP1 by increasing expression of MST1, and the increase in MST1 protein antagonizes YAP1 to suppress HCC progression. Finally, we demonstrated that USP46 stabilizes the MST1 protein by directly binding to it and decreasing its ubiquitination. Taken together, our results demonstrated that USP46 may be a novel tumor suppressor in HCC. Moreover, USP46 acts as a deubiquitinating enzyme of MST1 to potentiate MST1 kinase activity to suppress tumor growth and metastasis, indicating that USP46 activation may represent a potential treatment strategy for HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Endopeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator de Crescimento de Hepatócito/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas/metabolismo , Ubiquitinação , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Endopeptidases/genética , Feminino , Fator de Crescimento de Hepatócito/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Fosforilação , Prognóstico , Proteínas Proto-Oncogênicas/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Surg Endosc ; 36(5): 3246-3253, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34524533

RESUMO

OBJECTIVE: To explore the utility of three-dimensional (3D) visualization technology in liver resection for patients with complex liver cancer. METHODS: In this retrospective cohort study, we collected and analyzed clinic pathological data from 105 patients who underwent complicated liver cancer resection at the authors' unit between January 2014 and June 2019. Observation indicators included general demographic information, operative time, intraoperative blood loss, blood transfusion volume, postoperative liver function, complication rate, hospital stay, and in-hospital mortality. RESULTS: Compared with the complex liver cancer control group, operative time (257.1  ±  63.4 min versus [vs] 326.6 ± 78.3 min; P < 0.001), intraoperative blood loss (256.4 ± 159.1 mL vs 436.1 ± 177.3 mL; P < 0.001), blood transfusion volume (213.3 ± 185.2 mL vs 401.6 ± 211.2 mL; P < 0.001), and length of hospital stay (9.7 ± 3.1 days vs 11.9 ± 3.3 days; P = 0.001) were significantly reduced in the complex liver cancer reconstruction group. Although there was no statistical difference in total postoperative complication rate between the two groups, the incidence of serious postoperative complications in the reconstruction group was significantly lower than that in the control group (3/54 [5.6%] vs 10/51 [19.6%], respectively; P = 0.038). Regarding laboratory investigations, the time to recovery of liver function in the complex liver cancer reconstruction group was shorter than that in the complex liver cancer control group. CONCLUSION: The use of 3D visualization technology was highly influential in formulating meticulous, individualized surgical strategies for complex liver cancer liver resection with safety and reduced perioperative risk.


Assuntos
Imageamento Tridimensional , Neoplasias Hepáticas , Perda Sanguínea Cirúrgica , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
9.
Pediatr Surg Int ; 38(3): 465-472, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35032209

RESUMO

BACKGROUND: Hepatoblastoma (HB) is a common primary malignant liver tumour in children, mainly treated by means of traditional chemotherapy using platinum and doxorubicin (ADM). There has been limited progress in the research and development of new drugs for treating HB. METHODS: A tumour biopsy from a child with HB was implanted into immunodeficient mice. The primary tumour and patient-derived xenograft (PDX) tumour were extensively characterised by histology, immunohistochemistry (IHC), and humanisation identification. We used the PDX model to evaluate the anti-tumour effects of anlotinib oxaliplatin (L-OHP) and sorafenib on childhood HB. RESULTS: The established PDX model maintained the histological characteristics of the primary tumour. Anlotinib, L-OHP, and sorafenib can significantly inhibit the tumour growth in the PDX model. There was no obvious damage of the drugs to the heart, liver and kidney of the mice, and the side effects observed were light. CONCLUSION: We have successfully established a PDX model of childhood HB. The model retains important molecular characteristics of human primary tumours. Using the model, it was found that anlotinib, L-OHP, and sorafenib have a good inhibitory effect on the growth of childhood HB. This provides a preliminary research basis for the clinical application of the drugs.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Animais , Hepatoblastoma/tratamento farmacológico , Xenoenxertos , Humanos , Indóis , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Oxaliplatina , Quinolinas , Sorafenibe
10.
Environ Res ; 183: 109241, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062184

RESUMO

Photochemical/photocatalytic reaction, one of the aging pathway of biochar in soil, not only changed the physicochemical properties of biochar, but also affected the migration and transformation of pollutants. Wheat straw biochar was photocatalytic aged in a Fenton-like system using organic acid as buffer solution under light sources, the organic carbon release and surface chemical changes of biochar were investigated to illustrate the adsorption behaviors. With Fe(III) or α-Fe2O3 added, the total organic carbon (TOC) of aged biochar solution was influenced more by buffer system than light sources, with the highest of 420.59 mg L-1 in citric acid system. The production of the hydroxyl radical (OH·) at citric/Fe(III) system was higher than the oxalic/Fe(III) system under the Hg lamp and showed an increasing trend with time. With light exposure, the porous structure of the biochar altered and surface area increased from 7.613 to 29.74 m2 g-1. Meanwhile, the adsorption of cadmium ion by biochar aged in citric/Fe(III) system also showed an increased adsorption capacity with a maximum of 73.54 mg g-1. So, a well understanding of biochar physicochemical properties changes under natural ecosystem was undoubtedly useful for scientific assessment the long-term feasibility of biochar as soil remediation.


Assuntos
Carvão Vegetal , Ecossistema , Poluentes do Solo , Solo , Adsorção , Cádmio , Carbono , Compostos Férricos
11.
Ecotoxicol Environ Saf ; 205: 111169, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827961

RESUMO

The characteristics and content of organo-mineral complex were confirmed to be changed in agriculture soils under the biochar application with long-term, but the resulting environmental effects in the retention and lasting of agrochemicals and xenobiotic pollutants is far from clear. In this study, biochar-soil composites were prepared by one-step dry ball-milling method, and a sorption case study was proceed to investigate the biochar incorporated affection in soils on the transport of dimethyl phthalate (DMP). More surface oxygen-containing functional groups on ball-milled biochar enhanced its complexation with soil minerals. Sorption isotherms of DMP onto the biochar-soil composites were well described by the Freundlich model, both heterogeneous surface and multilayer interactions occurred simultaneously. The kinetics of sorption could be simulated with the pseudo-second-order model (R2 > 0.98), while the average sorption energy (Ea) calculated from Dubinin-Radushkevich isotherms were found in the range of 3.83-5.60 kJ mol-1, which revealed that the sorption processes coexist of chemisorption and physisorption, and π-π electron donor-acceptor interaction, pore-filling and hydrophobic interactions could be identified as the main sorption mechanisms. Desorption of absorbed DMP appeared obvious nonlinear characteristics and lag effect, the calculated hysteresis index (HI) increased with the application of biochar into soil. Considering the phenomenon of biochar aging and soil complexation, it is important to verify how the transport and natural attenuation of contaminant will be influenced by biochar addition, especially the long-term effect in soil ecosystem.


Assuntos
Carvão Vegetal/química , Ácidos Ftálicos/análise , Poluentes do Solo/análise , Solo/química , Adsorção , Agricultura , Ecossistema , Ésteres , Cinética , Modelos Teóricos , Propriedades de Superfície
12.
Hepatology ; 68(6): 2268-2284, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29790184

RESUMO

Recently, studies on transcriptome-proteome relationships have revealed mRNA/protein expression discordance for certain genes and speculated that protein posttranslational modification (PTM) may be involved. However, there is currently no evidence to support this hypothesis. Wnt-induced secreted protein-1 (WISP1) is the downstream target gene of ß-catenin and plays an important role in tumorigenesis and progression, but the expression and role of WISP1 in different tumor types are controversial. Here, we first confirmed that WISP1 protein expression was significantly down-regulated in hepatocellular carcinoma (HCC) tissue and could be an independent predictor of poor prognosis for patients with HCC. In vivo and in vitro evidence was provided that WISP1 can suppress HCC cell proliferation. Further studies have found that low WISP1 protein expression was related to expression of human leukocyte antigen F locus adjacent transcript 10 (FAT10), a specific ubiquitin-like protein with both degradation and stabilization functions, which plays an important role in PTM. FAT10 overexpression facilitated WISP1 degradation by FAT10ylation to decrease WISP1 protein expression, thus promoting HCC proliferation. Interestingly, we found and demonstrated that FAT10 overexpression could result in WISP1 protein/mRNA expression discordance, with protein expression decreasing while mRNA expression increased. The underlying mechanism is that FAT10 exerts substrate stabilization and degradation functions simultaneously, while FAT10 overexpression promotes WISP1 mRNA expression by stabilizing ß-catenin and directly degrades WISP1 protein. Conclusion: Our study demonstrated that overexpression of FAT10 results in expression discordance between WISP1 protein and mRNA, thereby promoting HCC progression by down-regulating WISP1 protein expression.


Assuntos
Proteínas de Sinalização Intercelular CCN/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ubiquitinas/metabolismo , Animais , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos Nus , Pessoa de Meia-Idade , beta Catenina/metabolismo
13.
J Nanosci Nanotechnol ; 19(4): 2124-2129, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486955

RESUMO

Electrocatalytic oxidation of nitrite at multi-walled carbon nanotubes (MWCNTs) modified electrode was investigated by using voltammetric techniques. The kinetic parameters such as diffusion coefficient (D), standard heterogeneous rate constant (ks) and catalytic constant (kh) were studied by chronocoulometry and chronoamperometry. The corresponding parameters for D, ks, and kh were caculated to be 3.56×10-5 cm² s-1, 6.29×10-3 cm s-1 and 7.02×10² M-1 s-1, respectively. The modified electrode was used for the determination of nitrite with a concentration range of 0.5 to 36 µM and a detection limit of 0.08 µM. The proposed method was successfully applied for the determination of nitrite in real samples of tap water and juice of pickled garlic.

14.
Ecotoxicol Environ Saf ; 184: 109612, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476450

RESUMO

Microplastics (MPs) are small plastic pieces with size less than 5 mm that have entered and polluted the environment. While many investigations including several critical reviews on MPs in the environment have been conducted, most of them are focused on their occurrences in marine environment. Current understanding on the occurrences, behaviors, and impacts of MPs in the terrestrial environment is far from complete. A systematic review of the literature was thus conducted to promote the research on MPs in the environment. This work is designed to provide a comprehensive overview that summarizes current knowledge and research findings on environmental occurrences, fate and transport, and impacts of MPs. In addition to discussing the occurrences, characteristics, and sources of MPs in the ocean, freshwater, sediments, soils, and atmosphere, the review also summarizes both the experimental and modeling data of the environmental fate and transport of MPs. Research findings on the toxic effects, bioaccumulation, and bioavailability of MPs in the environment are also covered in this critical review. Future perspectives are discussed as well.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Poluição Ambiental/análise , Microplásticos/análise , Disponibilidade Biológica , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Poluição Ambiental/efeitos adversos , Microplásticos/metabolismo , Microplásticos/toxicidade , Modelos Teóricos
15.
J Environ Sci (China) ; 55: 197-205, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28477813

RESUMO

The phosphorus (P) fraction distribution and formation mechanism in the supernatant after P adsorption onto iron oxides and iron oxide-humic acid (HA) complexes were analyzed using the ultrafiltration method in this study. With an initial P concentration of 20mg/L (I=0.01mol/L and pH=7), it was shown that the colloid (1kDa-0.45µm) component of P accounted for 10.6%, 11.6%, 6.5%, and 4.0% of remaining total P concentration in the supernatant after P adsorption onto ferrihydrite (FH), goethite (GE), ferrihydrite-humic acid complex (FH-HA), goethite-humic acid complex (GE-HA), respectively. The <1kDa component of P was still the predominant fraction in the supernatant, and underestimated colloidal P accounted for 2.2%, 55.1%, 45.5%, and 38.7% of P adsorption onto the solid surface of FH, FH-HA, GE and GE-HA, respectively. Thus, the colloid P could not be neglected. Notably, it could be interpreted that Fe3+ hydrolysis from the adsorbents followed by the formation of colloidal hydrous ferric oxide aggregates was the main mechanism for the formation of the colloid P in the supernatant. And colloidal adsorbent particles co-existing in the supernatant were another important reason for it. Additionally, dissolve organic matter dissolved from iron oxide-HA complexes could occupy large adsorption sites of colloidal iron causing less colloid P in the supernatant. Ultimately, we believe that the findings can provide a new way to deeply interpret the geochemical cycling of P, even when considering other contaminants such as organic pollutants, heavy metal ions, and arsenate at the sediment/soil-water interface in the real environment.


Assuntos
Compostos Férricos/química , Modelos Químicos , Fósforo/química , Adsorção , Arseniatos , Coloides , Substâncias Húmicas , Concentração de Íons de Hidrogênio , Compostos de Ferro , Minerais , Compostos Orgânicos , Óxidos , Solo , Ultrafiltração
16.
Water Sci Technol ; 74(8): 1821-1831, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27789883

RESUMO

In this work, the hierarchically porous biomass carbon (HPBC) was originally prepared for desalination through a simple activation of cheap biomass carbon (BC). Such crucial activated conditions as the KOH/C ratio, the activation time and the activation temperature were deeply investigated. It is demonstrated that the activated conditions had a great influence on the structure properties and electrochemical performance. According to structure and surface analyses, the HPBC with larger surface area and hierarchical porous structure could be well obtained in suitable activation conditions. The electrochemical analyses showed that the HPBC showed increased electrosorption capacitance, lower inner resistance and good stability, which can be attributed to large accessible surface area and smooth ion transportation. In the further desalination test, the HPBC electrode exhibited enhanced desalination efficiency and capacity. Hence, HPBC can be a promising candidate electrode material for desalination with low cost and high efficiency.


Assuntos
Carbono/química , Hidróxidos/química , Compostos de Potássio/química , Cloreto de Sódio/química , Eliminação de Resíduos Líquidos/métodos , Biomassa , Porosidade , Temperatura
17.
J Environ Sci (China) ; 42: 152-162, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27090706

RESUMO

Iron oxide (FeO) coated by natural organic matter (NOM) is ubiquitous. The associations of minerals with organic matter (OM) significantly changes their surface properties and reactivity, and thus affect the environmental fate of pollutants, including nutrients (e.g., phosphorus (P)). In this study, ferrihydrite/goethite-humic acid (FH/GE-HA) complexes were prepared and their adsorption characteristics on P at various pH and ionic strength were investigated. The results indicated that the FeO-OM complexes showed a decreased P adsorption capacity in comparison with bare FeO. The maximum adsorption capacity (Qmax) decreased in the order of FH (22.17 mg/g)>FH-HA (5.43 mg/g)>GE (4.67 mg/g)>GE-HA (3.27 mg/g). After coating with HA, the amorphous FH-HA complex still showed higher P adsorption than the crystalline GE-HA complex. The decreased P adsorption observed might be attributed to changes of the FeO surface charges caused by OM association. The dependence of P adsorption on the specific surface area of adsorbents suggests that the FeO component in the complexes is still the main contributor for the adsorption surfaces. The P adsorptions on FeO-HA complexes decreased with increasing initial pH or decreasing initial ionic strength. A strong dependence of P adsorption on ionic strength and pH may demonstrate that outer-sphere complexes between the OM component on the surface and P possibly coexist with inner-sphere surface complexes between the FeO component and P. Therefore, previous over-emphasis on the contributions of original minerals to P immobilization possibly over-estimates the P loading capacity of soils, especially in humic-rich areas.


Assuntos
Compostos Férricos/química , Modelos Químicos , Fósforo/química , Poluentes do Solo/química , Adsorção , Substâncias Húmicas , Concentração de Íons de Hidrogênio , Compostos de Ferro , Minerais , Solo/química , Propriedades de Superfície
18.
J Environ Qual ; 44(5): 1631-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26436279

RESUMO

The movement and fate of herbicides in soils under various environmental factors are important in evaluating their mobility and ecological impact. The effects of sterilization, solarization, and soil physicochemical properties on the degradation of herbicide mesotrione in three soils from China were evaluated using laboratory incubation method, and the degradation kinetics were also simulated using pseudo first-order reaction model. The calculated half-lives () of mesotrione were found to be 3.78- to 5.24-fold increased in sterilized soils than nonsterilized soils, which indicated that the degradation of mesotrione was strongly affected by soil microbial activity. A certain role of promoting degradation effect of natural light was found, and the values appeared to be only 7.90, 15.89, and 25.29 d in the surface of paddy soil, sandy loess, and silt clay loam, respectively. Correlation analysis between the observed first-order reaction rate constant () values and the selected soil properties revealed that the degradation of mesotrione was highly dependent on soil pH value ( > 0.992) and organic matter content ( > 0.932), but less related with clay content (<0.02 mm) with < 0.761 and nonrelated with cation exchange capacity (CEC) ( < 0.164). Data obtained in this study are helpful for further research on the prediction of the movement and fate of mesotrione in soils in limiting its environmental impact.

19.
Environ Pollut ; 342: 123025, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040185

RESUMO

Transformation, fragmentation, dissolution, and oxidation of biochar are inevitable in the environment, which will undoubtedly accelerate the release of biochar-derived dissolved organic matter (BDOM) into various water bodies. In addition, biochar may affect disinfection by-products (DBPs) during water treatment and subsequent disinfection. In this study, biochars were derived at three selected pyrolysis temperatures (350 °C, 500 °C, and 650 °C) from rice husk, wheat straw, and shrimp shell, and BDOM was extracted from biochar-derived in artificial seawater and ultrapure water. The TOC analyzer results showed that the concentrations of three BDOM decreased with increasing pyrolysis temperature. The BDOM derived from rice husk biochar and wheat straw biochar in seawater was lower than that in ultrapure water, while that of shrimp shell biochar showed an opposite trend, being released in seawater at nearly twice the extent of that in ultrapure water at 350 °C. Moreover, BDOM showed a catalytic effect on chlorination, and GC analysis showed that the concentrations of its DBPs were affected by pH. The concentration of halogenated acetic acid reached the highest value (54.51 µg/L) in weak acidic environment, while the concentrations of trihalomethane and halogenated acetonitrile had the highest values (23.63 and 47.53 µg/L, respectively) in alkaline conditions. The concentrations of all the three DBPs were lowest under neutral pH conditions. In addition, the volatile halogenated DBPs such as dichloroacetone and trichloroacetone were easily hydrolyzed under alkaline conditions. Therefore, it is something be aware of the release of BDOM and the effects of chlorination DBPs when biochar is used for water treatment or water purification.


Assuntos
Carvão Vegetal , Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Desinfecção/métodos , Cloro/análise , Halogenação , Matéria Orgânica Dissolvida , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise
20.
Sci Rep ; 14(1): 9196, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649699

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human malignancies. Uncontrolled cell proliferation, invasion and migration of pancreatic cancer cells are the fundamental causes of death in PDAC patients. Our previous studies showed that KLF9 inhibits the proliferation, invasion and migration of pancreatic cancer cells. However, the underlying mechanisms are not fully understood. In this study, we found that platelet-activating factor acetylhydrolase IB3 (PAFAH1B3) is highly expressed in pancreatic cancer tissues and cells. In vitro and in vivo studies showed that overexpression of PAFAH1B3 promoted the proliferation and invasion of pancreatic cancer cells, while downregulation of PAFAH1B3 inhibited these processes. We found that KLF9 expression is negatively correlated with PAFAH1B3 expression in pancreatic cancer tissues and cells. Western blotting revealed that KLF9 negatively regulates the expression of PAFAH1B3 in pancreatic cancer tissues and cells. Rescue experiments showed that overexpression of PAFAH1B3 could partially attenuate the suppression of pancreatic cancer cell proliferation, invasion and migration induced by KLF9 overexpression. Finally, chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were carried out, and the results showed that KLF9 directly binds to the promoter of PAFAH1B3 and inhibits its transcriptional activity. In conclusion, our study indicated that KLF9 can inhibit the proliferation, invasion, migration and metastasis of pancreatic cancer cells by inhibiting PAFAH1B3.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like , Neoplasias Pancreáticas , Animais , Feminino , Humanos , Masculino , Camundongos , 1-Alquil-2-acetilglicerofosfocolina Esterase/genética , 1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo
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