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1.
Acta Biomater ; 185: 226-239, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38972625

RESUMO

Polymeric elastomers are widely utilized in implantable biomedical devices. Nevertheless, the implantation of these elastomers can provoke a robust foreign body response (FBR), leading to the rejection of foreign implants and consequently reducing their effectiveness in vivo. Building effective anti-FBR coatings on those implants remains challenging. Herein, we introduce a coating-free elastomer with superior immunocompatibility. A super-hydrophilic anti-fouling zwitterionic layer can be generated in situ on the surface of the elastomer through a simple chemical trigger. This elastomer can repel the adsorption of proteins, as well as the adhesion of cells, platelets, and diverse microbes. The elastomer elicited negligible inflammatory responses after subcutaneous implantation in rodents for 2 weeks. No apparent fibrotic capsule formation was observed surrounding the elastomer after 6 months in rodents. Continuous subcutaneous insulin infusion (CSII) catheters constructed from the elastomer demonstrated prolonged longevity and performance compared to commercial catheters, indicating its great potential for enhancing and extending the performance of various implantable biomedical devices by effectively attenuating local immune responses. STATEMENT OF SIGNIFICANCE: The foreign body response remains a significant challenge for implants. Complicated coating procedures are usually needed to construct anti-fibrotic coatings on implantable elastomers. Herein, a coating-free elastomer with superior immunocompatibility was achieved using a zwitterionic monomer derivative. A pure zwitterionic layer can be generated on the elastomer surface through a simple chemical trigger. This elastomer significantly reduces protein adsorption, cell and bacterial adhesion, and platelet activation, leading to minimal fibrotic capsule formation even after six months of subcutaneous implantation in rodents. CSII catheters constructed from the PQCBE-H elastomer demonstrated prolonged longevity and performance compared to commercial catheters, highlighting the significant potential of PQCBE-H elastomers for enhancing and extending the performance of various implantable biomedical devices.


Assuntos
Elastômeros , Fibrose , Reação a Corpo Estranho , Elastômeros/química , Elastômeros/farmacologia , Animais , Reação a Corpo Estranho/patologia , Camundongos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Próteses e Implantes , Propriedades de Superfície , Ratos , Masculino , Ratos Sprague-Dawley , Catéteres
2.
Graefes Arch Clin Exp Ophthalmol ; 262(10): 3305-3312, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38700591

RESUMO

PURPOSE: To identify the types of viral infection in aqueous humor (AqH) among patients diagnosed as Fuchs uveitis syndrome (FUS) or Posner-Schlossman syndrome (PSS) and investigate their relevance to clinical manifestations and visual outcome. METHODS: A total of 375 patients and 171 patients were diagnosed as FUS or PSS in our department. AqH and serum samples from 68 FUS patients and 16 PSS patients were obtained during eye surgery. The viral etiologies, clinical features, auxiliary tests and visual prognosis of patients with FUS or PSS who underwent AqH analysis were analysed and compared. RESULTS: Among 68 FUS patients, rubella virus (RV), cytomegalovirus (CMV), herpes simplex virus (HSV) and varicella-zoster virus were identified in 17, 11, 1 and 1 patients, respectively. Seven patients with CMV and 1 with HSV were identified in 16 PSS patients. In both FUS and PSS groups, virus-associated eyes had higher proportion of secondary glaucoma and worse visual prognosis as compared with non-virus-associated eyes (all P < 0.05). In FUS group, specifically, CMV infection manifested as more obvious anterior segment inflammation and lower corneal endothelial cell density (CECD). RV infection showed a higher percentage of vitritis. In PSS group, CMV-associated PSS had a lower retinal nerve fiber layer thickness and CECD, worse visual prognosis as compared with non-virus-associated PSS (all P < 0.05). CONCLUSION: Our study identified 4 types of viral infection in FUS and 2 types of viral infection in PSS. Virus-associated patients are usually associated with more obvious clinical signs and poor visual prognosis.


Assuntos
Humor Aquoso , Infecções Oculares Virais , Acuidade Visual , Humanos , Infecções Oculares Virais/diagnóstico , Infecções Oculares Virais/virologia , Masculino , Feminino , Humor Aquoso/virologia , Pessoa de Meia-Idade , China/epidemiologia , Adulto , Estudos Retrospectivos , Idoso , Síndrome , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Prognóstico , Uveíte/diagnóstico , Uveíte/virologia , Seguimentos , Adulto Jovem , Uveíte Anterior/diagnóstico , Uveíte Anterior/virologia , Distrofia Endotelial de Fuchs/diagnóstico , População do Leste Asiático
3.
Clin Exp Rheumatol ; 42(9): 1792-1801, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38757282

RESUMO

OBJECTIVES: To investigate whether the interplay of anti-galectin-3 antibodies (anti-Gal3 Abs) with neutrophils contributes to the development of lupus cutaneous vasculitis. METHODS: Enzyme-linked immunosorbent assay was used to determine the serum level of anti-Gal3 Abs in lupus patients. Flow cytometry, quantitative PCR and western blot were performed to investigate the expression of cell surface receptors, proinflammatory cytokines and signalling molecules in neutrophils stimulated by serum from lupus patients or healthy controls (HCs) or anti-Gal3 Ab, respectively. Immunofluorescence was performed to visualise the formation of neutrophil extracellular traps (NETs). Human umbilical vein endothelial cells were co-cultured with the supernatants from neutrophils stimulated by anti-Gal3 Ab, and cytokine production was measured at mRNA and protein levels. Immunohistochemistry was adopted to reveal the distribution of Gal3, cytokines and myeloperoxidase within lupus skin lesions. RESULTS: Serum levels of anti-Gal3 Abs were negatively correlated with peripheral counts of neutrophils. Anti-Gal3 Abs positive sera from SLE patients accelerated neutrophil death, altered cell phenotype and promoted formation of NETs with the involvement of p38 MAPK pathway. Supernatants collected from neutrophils co-cultured with anti-Gal3 Ab provoked endothelial cells to produce cytokines such as IL-1, ICAM-1, SELE and particularly IL-6. Consistently, IL-6 was higher in SLE patients with anti-Gal3 Ab positive sera and enriched in the area of vascular inflammation together with enhanced expression of Gal3 protein and infiltration of neutrophils. CONCLUSIONS: Overall, these findings suggested that neutrophils were crucial mediators in anti-Gal3 Ab induced lupus cutaneous vasculitis.


Assuntos
Armadilhas Extracelulares , Lúpus Eritematoso Cutâneo , Neutrófilos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Autoanticorpos/sangue , Proteínas Sanguíneas , Estudos de Casos e Controles , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Selectina E , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Galectinas , Células Endoteliais da Veia Umbilical Humana/imunologia , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/sangue , Molécula 1 de Adesão Intercelular , Lúpus Eritematoso Cutâneo/imunologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Peroxidase/imunologia , Peroxidase/metabolismo , Fenótipo , Transdução de Sinais , Pele/imunologia , Pele/patologia
4.
ACS Appl Bio Mater ; 6(12): 5621-5629, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37983123

RESUMO

Hydrogels with the features of softness, biocompatibility, and modifiability have emerged as excellent materials in the biomedical field. However, the poor mechanical properties of the hydrogels limit their further practical applications. Double-network and metal ion coordination, such as Cu2+ and Zn2+, have achieved a significant reinforcement of the mechanical strength of the hydrogels. Herein, we report a Zn2+-enhanced polyelectrolyte double-network hydrogel stent with a mechanical enhancement phenomenon in bile. The gelatin/poly(zinc acrylate) (PZA) stent was constructed by dip-coating and UV irradiation. Although the mechanical strength of the as-prepared stent was quite weak, it was discovered to be mechanically enhanced by the natural bile. After exploring the effect of different components on the stents according to the components of bile, we found that Ca2+ in bile made a contribution to the mechanical enhancement of the stent. It is envisioned that this bile-enhanced gelatin/PZA stent provides a train of thought for the potential application of hydrogels in the biliary environment.


Assuntos
Gelatina , Zinco , Hidrogéis/uso terapêutico , Bile , Stents
5.
Clin Immunol ; 256: 109800, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37821074

RESUMO

The resistance development of the combination regimen of corticosteroids (CS) with cyclosporin A (CsA) leads to therapeutic failure of some patients with autoimmune diseases. In the male patients with Vogt-Koyanagi-Harada (VKH) disease, we have identified RPS4Y1 as an important resistance gene of the regimen and a functional mediator of chlorambucil (CLB). However, it remains unclear what is responsible for the resistance in female patients. In the present study, we performed RNA sequencing, tandem mass tag (TMT) proteomics, gain- and loss-of-function assays and rescue assays to screen and validate potential resistant mediators. The results showed that only Fc epsilon receptor Ig (FCER1G) exhibited significantly differential expression in CD4+ T cells among female CsA & CS resistant, sensitive and CLB & CsA & CS treated patients at transcription and protein levels. Inhibition of FCER1G was demonstrated to modulate CD4+ T cell resistance to CsA & CS in female patients. Importantly, the inhibition was mediated by elevated DNA methylation in the promoter region of the FCER1G gene. Moreover, we found that the salvage effect of CLB on CsA & CS resistance was mediated by an increased FCER1G expression via DNA demethylation in female patients. Taken together, the downregulation of FCER1G due to DNA hypermethylation is responsible for the resistance to CsA & CS and CLB reverses this resistance by inducing FCER1G expression via DNA demethylation in female patients. Modulation of FCER1G would be a promising sensitization strategy in female patients with resistance to CsA & CS.


Assuntos
Ciclosporina , Síndrome Uveomeningoencefálica , Feminino , Humanos , Masculino , Corticosteroides/uso terapêutico , Ciclosporina/uso terapêutico , Regulação para Baixo , Linfócitos T/metabolismo , Síndrome Uveomeningoencefálica/tratamento farmacológico , Síndrome Uveomeningoencefálica/genética
6.
Immunopharmacol Immunotoxicol ; 45(6): 692-700, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37358143

RESUMO

OBJECTIVE: Treatment with TNF-α inhibitors improve psoriasis with minimize/minor neutrophils infiltration and CXCL-1/8 expression in psoriatic lesions. However, the fine mechanism of TNF-α initiating psoriatic inflammation by tuning keratinocytes is unclear. Our previous research identified the deficiency of intracellular galectin-3 was sufficient to promote psoriasis inflammation characterized by neutrophil accumulation. This study aims to investigate whether TNF-α participated in psoriasis development through dysregulating galectin-3 expression. METHODS: mRNA levels were assessed through quantitative real-time PCR. Flow cytometry was used to detect cell cycle/apoptosis. Western blot was used to evaluate the activation of the NF-κB signaling pathway. HE staining and immunochemistry were used to detect epidermal thickness and MPO expression, respectively. Specific small interfering RNA (siRNA) was used to knock down hsa-miR-27a-3p while plasmids transfection was used to overexpress galectin-3. Further, the multiMiR R package was utilized to predict microRNA-target interaction. RESULTS AND DISCUSSION: We found that TNF-α stimulation altered cell proliferation and differentiation and promoted the production of psoriasis-related inflammatory mediators along with the inhibition of galectin-3 expression in keratinocytes. Supplement of galectin-3 could counteract the rise of CXCL-1/8 but not the other phenotypes of keratinocytes induced by TNF-α. Mechanistically, inhibition of the NF-κB signaling pathway could counteract the decrease of galectin-3 and the increase of hsa-miR-27a-3p expression whereas silence of hsa-miR-27a-3p could counteract the decrease of galectin-3 expression induced by TNF-α treatment in keratinocytes. Intradermal injection of murine anti-CXCL-2 antibody greatly alleviated imiquimod-induced psoriasis-like dermatitis. CONCLUSION: TNF-α initiates psoriatic inflammation by increasing CXCL-1/8 in keratinocytes mediated by the axis of NF-κB-hsa-miR-27a-3p-galectin-3 pathway.


Assuntos
Galectina 3 , Queratinócitos , MicroRNAs , Psoríase , Fator de Necrose Tumoral alfa , Fator de Necrose Tumoral alfa/farmacologia , Queratinócitos/metabolismo , Células HaCaT , Humanos , MicroRNAs/genética , Quimiocina CXCL1/metabolismo , Interleucina-8/metabolismo , Galectina 3/genética , Psoríase/genética , Psoríase/patologia , NF-kappa B/metabolismo , Transdução de Sinais , Feminino , Animais , Camundongos , Camundongos Endogâmicos C57BL
7.
J Mater Chem B ; 11(22): 4882-4889, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37222145

RESUMO

Drug-coated balloon (DCB) is a therapeutic method that can effectively deliver antiproliferative drugs such as paclitaxel and rapamycin (RAPA) with no permanent implants left behind. However, delayed reendothelialization due to the toxicity of the delivered drugs leads to poor therapeutic effects. Here, we propose a new design of DCB coating, which incorporates both vascular endothelial growth factor (VEGF)-encoding plasmid DNA (pDNA) that can promote endothelial repair and RAPA into protamine sulfate (PrS). We demonstrate that the PrS/pDNA/RAPA coating had stability and good anticoagulation properties in vitro. We further show that the coating exhibited excellent transfer capacity from balloon substrates to vessel walls both in vitro and in vivo. Furthermore, the PrS/pDNA/RAPA coating effectively inhibited neointimal hyperplasia after balloon-induced vascular injuries through the down-regulation of the mammalian target of Rapamycin (mTOR) and promoted endothelium regeneration through increased expression of VEGF in vivo. These data indicate that our nanocomposite coating has great potential for use as a novel coating of DCB to treat neointimal hyperplasia after vascular injuries.


Assuntos
Fator A de Crescimento do Endotélio Vascular , Lesões do Sistema Vascular , Humanos , Sirolimo/farmacologia , Hiperplasia/tratamento farmacológico , Plasmídeos , DNA , Fatores de Crescimento do Endotélio Vascular
8.
JAMA Netw Open ; 6(2): e2255804, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787142

RESUMO

Importance: Improper host response to COVID-19 vaccines could trigger immune-mediated adverse events. The question remains whether COVID-19 vaccination should be postponed until complete remission in patients with uveitis, a preexisting immune-related condition. Objective: To compare recommendations for early and deferred COVID-19 vaccination with respect to uveitis outcomes. Design, Setting, and Participants: This open-label, randomized clinical trial at a large, specialized teaching center for uveitis care in China enrolled unvaccinated patients with inactive uveitis between August 10, 2021, and February 22, 2022, with follow-up to June 6, 2022. Interventions: Participants were randomly assigned to receive recommendation for early or deferred COVID-19 vaccination after complete remission of uveitis. Non-messenger RNA (non-mRNA) COVID-19 vaccines were available in China during the trial. Main Outcomes and Measures: The primary outcome was the time to symptomatic uveitis worsening during 3 months of follow-up. Secondary outcomes included uveitis activity and best-corrected visual acuity at 3 months. Results: Of the 543 participants (304 women [56.0%]; median age, 35 [IQR, 26-49] years), 262 were recommended for early vaccination and 281 for deferred vaccination. By month 3, 109 patients (41.6%) in the early group had been vaccinated compared with 14 (5.0%) in the deferred recommendation group. In the intention-to-treat population, the time to symptomatic uveitis worsening was shorter in the early group than in the deferred group (hazard ratio, 1.68 [95% CI, 1.09-2.59]; P = .01 by log-rank test). Changes in anterior chamber cells, vitreous haze, and best-corrected visual acuity from baseline to month 3 appeared similar in the 2 groups in the evaluable population after the month 3 in-person visit. Conclusions and Relevance: In this randomized clinical trial of patients with inactive uveitis, recommendation for early non-mRNA COVID-19 vaccination resulted in a higher incidence of self-reported symptomatic uveitis worsening with possible reporting bias compared with recommendation for deferred vaccination, but no adverse effects were observed in disease and visual prognosis at 3 months. These findings would be useful to guide the individual timing choices of non-mRNA COVID-19 vaccination in this clinically vulnerable population. Trial Registration: Chinese Clinical Trial Registry: ChiCTR2100049467.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Uveíte , Adulto , Feminino , Humanos , COVID-19/prevenção & controle , COVID-19/complicações , Vacinas contra COVID-19/uso terapêutico , População do Leste Asiático , RNA , Resultado do Tratamento , Vacinação , Masculino , Pessoa de Meia-Idade
9.
J Autoimmun ; 133: 102925, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36209692

RESUMO

OBJECTIVES: Several studies suggested that coronavirus disease 2019 (COVID-19) vaccination may lead to uveitis, a vision-threatening condition often associated with a variety of autoimmune or autoinflammatory diseases. This study aims to explore factors that influence the risk of uveitis relapse after COVID-19 vaccination to guide the prevention of disease. METHODS: Uveitis relapse was evidenced by worsening activity of intraocular inflammation (e.g. anterior chamber cells, vitreous haze) as defined by the Standardization of Uveitis Nomenclature Working Group. Time to uveitis relapse since the administration of each dose of COVID-19 vaccine was compared across participants with modifiable variables. RESULTS: The primary analysis included 438 non-COVID-19 participants with 857 doses of COVID-19 vaccine administered in total. The median age was 41 years (interquartile range, 30 to 51), and 57.3% were female. A total of 39 episodes of uveitis relapse events occurred in 34 patients after the receipt of a dose of COVID-19 vaccine within 30 days. The median time to relapse after vaccination was 5 days (interquartile range, 1 to 14). Concomitant use of systemic glucocorticoids at the time of vaccination was independently associated with a decrease in risk of relapse after vaccination (HR, 0.23 [95% CI, 0.07-0.74]; P value = 0.014). There was a trend in attenuating the risk of relapse with increasing prednisone dose from none to less than 20 mg per day and then to 20 mg per day or greater (P value for trend = 0.029). CONCLUSIONS: Concomitant treatment with systemic glucocorticoids for uveitis at the time of COVID-19 vaccination was associated with a dose-dependent lower risk of uveitis relapse after vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Feminino , Adulto , Masculino , COVID-19/prevenção & controle
11.
Biomater Sci ; 10(13): 3612-3623, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35642971

RESUMO

Drug-coated balloons (DCBs) offer potential to deliver drugs to treat coronary lesions but without leaving permanent implants behind. Paclitaxel and sirolimus are anti-proliferation drugs that are commonly used in commercially available DCBs. However, these drugs present significant cytotoxicity concern and low efficacy in vivo. Here, we use microRNA-22 (miR-22) as balloon loaded drugs and polyelectrolyte complexes (PECs) polyethyleneimine/polyacrylic acid (PEI/PAA) as balloon coatings to establish a new DCB system through the ultrasonic spray method. The PEI/PAA forms a stable and thin coating on the balloon, which resulted in a good transfer capacity to the vessel wall both in vitro and in vivo. miR-22 that could modulate smooth muscle cell (SMC) phenotype switching is incorporated into the PEI/PAA coating and shows a sustained release profile. The PEI/PAA/miR-22 coated balloon successfully inhibits intima hyperplasia after balloon-induced vascular injury in a rat model through decreasing proliferative SMCs via the miR-22-methyl-CpG binding protein 2 (MECP2) axis. Our findings indicate that balloons coated with PEI/PAA/miR-22 have great potential to be promising DCBs in the treatment of cardiovascular disease.


Assuntos
Angioplastia com Balão , MicroRNAs , Lesões do Sistema Vascular , Animais , Espessura Intima-Media Carotídea , Materiais Revestidos Biocompatíveis , Hiperplasia/prevenção & controle , MicroRNAs/genética , Paclitaxel/química , Polieletrólitos , Ratos
12.
Chemosphere ; 277: 130353, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33794436

RESUMO

A comprehensive human health risk assessment methodology based on major hazard element screening and morphological evolution simulation is proposed. The primary targeted metal (PTM) screened by classical health risk assessment was introduced into chemical balance simulation to obtain speciation distribution and corresponding risk. According to the results of risk assessment of morphological evolution of primary targeted metal (PTM), a potential methodology for the remediation is proposed, which could reduce the risk level efficiently and quickly by changing the pH of soil environment with additional acid and alkali substances. A case study was performed in a dye factory in Suzhou city, Jiangsu Province, China. The results of classical health risk assessment showed that the regional health risk index for children exceeded tolerance value of 1, in which Cr accounted for high risk level of 61%. Chemical balance simulation results showed that CrO42- and CaCrO4 had the highest risk index, and the change of pH value would affect the proportion of CrO42- and CaCrO4 in Cr6+ ionic speciation, which may indirectly change the risk level. It is recommended to adjust the pH of the soil environment to quickly reduce regional human health risk. This study will provide a theoretical basis for public health protection and site restoration management.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , China , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
13.
Chemosphere ; 263: 128109, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297102

RESUMO

Herein, the novel polyaniline@nano hollow carbon sphere (PANI@NHCS) adsorbents with different mass of NHCS were prepared by in-situ polymerization method. The microstructure of obtained PANI@NHCS-10, PANI@NHCS-20, PANI@NHCS-30 and PANI@NHCS-40 samples were observed through both scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which showed that the PANI@NHCS-30 possessed hollow structure like lappaceum shell. Then, the performance of obtained PANI@NHCS-30 was studied for removing hexavalent chromium (Cr(VI)) from waste water. With the help of unique hollow structure and reduction ability of PANI@NHCS-30, the Cr(VI) was fleetly adsorbed and then reduced to less toxic Cr(III). The maximum adsorption capacity was 250.0 mg/g for PANI@NHCS-30 under the optimal condition. Moreover, the effects of initial Cr(VI) concentration, solution pH and different ions on the adsorption performance were investigated in detail. Importantly, the PANI@NHCS-30 still shows superb adsorption ability after five cycles, which suggests its satisfactory reusability ability. The accumulated data revealed the crucial role of PANI and hollow structure co-promoting effect on Cr(VI) reduction reactions over PANI@NHCS-30, which could be applied to the practical use.


Assuntos
Carbono , Poluentes Químicos da Água , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise
14.
J Hazard Mater ; 393: 120448, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32155519

RESUMO

Herein, a novel three-dimensional (3D) heterogeneous Electro-Fenton (EF) system with improved gas diffusion electrode (GDE) as cathode and magnetic nitrogen doped/reduced graphene oxide (Fe3O4/N-rGO) as catalytic particle electrodes (CPEs) was built for Bisphenol A (BPA) removal. The Fe3O4/N-rGO served as both particle electrodes and heterogeneous catalyst. The study concluded that BPA could be effectively removed via this hybrid system. The synergistic effect between the 3D electrode and EF system was discussed by comparing the performance of different functional particle electrodes. The 3D electrode system exhibited a larger specific surface area electrode, which improved the mass transfer of pollutants to electrode, and also accelerated the regeneration of FeⅡ due to faster electron transfer, thereby enhancing the efficiency of EF catalysis. The EF process promotes the regeneration rate of particle electrodes and thus accelerates the 3D electrode reaction course. The parameters affecting degradation behavior of BPA were optimized. As a result, optimal removal rate of BPA and TOC was 93% and 60.5%, respectively within 90 min. The CPEs showed high catalytic performance (86.5% for BPA and 50.3% for TOC) and low catalyst loss (less than 9.5%) after 5 cycles, indicating its excellent stability and reusability. The possible mechanism of 3D heterogeneous EF was investigated by comparing the catalytic activity and •OH production capacity of homogeneous EF and Fenton-like. Built on the analysis of intermediates, a possible decomposition pathway of BPA was proposed.

15.
Sci Total Environ ; 686: 788-796, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31195286

RESUMO

In China groundwater contamination has become a serious problem. The assessment and remediation of contaminated sites are greatly important. Moreover, only few studies deal with the influence of metal speciation on human health risk assessment. This paper proposed a comprehensive assessment methodology combined human health risk assessment and groundwater vulnerability assessment for contaminated area, exploring a more reasonable model for the Cd morphology simulation, and utilizing accurate method to calculate the average daily dose by the weight analysis. PHREEQC and Visual MINTEQ were applied and compared to the morphology simulation, the modified of average daily dose and non-modified of average daily dose was investigated, carcinogenic and non-carcinogenic risks were calculated subsequently. The groundwater vulnerability was assessed by the DRASTIC model, the DRASTIC index as the indicator of groundwater vulnerability. The morphology simulation results showed 20 and 13 metal species which were simulated by PHREEQC and Visual MINTEQ, respectively. Cd2+ and CdCl+ were the primary species of Cd in groundwater. The modified average daily dose showed less than the average daily dose in results. The carcinogenic risks showed the species of Cd2+ and CdCl+ were simulated by PHREEQC which were harmful to human health. The DRASTIC index was ranged from 109 to 134 in the studied area, which showed that the area was susceptible to pollution. This method provided a more effective risk assessment model and supplied a fundamental advice for government policy-making and site remediation.

16.
J Hazard Mater ; 369: 770-779, 2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-30851517

RESUMO

In this study, MnO2/MWCNT hybrids, prepared using a solvothermal method, were coated onto Ni foam and then used as a cathode for tetrabromobisphenol A (TBBPA) degradation. The reaction was confirmed to exhibit the pseudo first-order kinetics. Compared with the original Ni foam cathode, the fabricated electrode exhibited higher catalytic activity, attributed to its strong cross-linking and ability to produce catalytic free radicals. Radical scavenger experiments revealed that O2- and OH were involved in the decomposition of TBBPA. The effects of current density, pH, catalyst dosage, and initial TBBPA concentration on removal efficiency were further studied. An optimal removal rate of 98.3% was achieved while the rate constant reached values up to 0.07293 min-1 and the debromination rate was more than 75.4% within 60 min. The electrode showed high catalytic performance and low catalyst loss after 10 cycles, indicating its excellent stability and reusability. The probable mechanism and pathway of TBBPA degradation were suggested based on the analysis of intermediate products. It could be inferred that the decomposition of TBBPA involved CC bond breaks (oxidation) and debromination (reduction). The MnO2/MWCNT-Ni foam could be a promising cathode material for electrochemical degradation of halogenated organic compounds.

17.
Ecotoxicol Environ Saf ; 171: 211-221, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30611039

RESUMO

Enriched and bio-refractory soil heavy metals (SHMs) originate from the underground mineral, which supplies energy and materials for the development of economy and industry. Investigating soil metal contents and their adverse health impacts is the principal concern associated metal contaminated industrial areas, including both current assessments and future projections. In this research, we create a novel spatiotemporal model of SHMs prediction and risk characterization for future by citing a rigorous theory of industrial economics, and time series of activity intensity changes of various pollution sources are forecasted. The dynamic change of source contributions is quantitatively resolved and the mean SHMs concentrations are estimated by classical formulas for heavy metal accumulation. Human health risk in the future is described in a manner of time series. The results of the case study show that contribution rates of the five sources of the six metals change continuously over time. Pb, Cd and As assume the highest growth rates (400%, 500% and 165%), while Zn, Ni, Cr possesses relatively lower growth (< 130%), compared to their corresponding background values. Health risk of local sensitive population (children) is estimated at exceeding threshold in 2022 (non-carcinogenic) and 2012 (carcinogenic), and the upward trend will continue. Traffic emission, agriculture and household garbage are identified as major risky sources in the coming decades at the studied area, and improvement measures are recommended. Although a degree of uncertainties exists, the overall tendency is a conservative bias for chemical risk. Additionally, this paper is the first to explore a methodology of predicting future SHMs and associated human health risk, based on industrial economics and temporal source apportionment.


Assuntos
Monitoramento Ambiental/métodos , Indústrias , Metais Pesados/análise , Modelos Teóricos , Poluentes do Solo/análise , Solo/química , Agricultura , Criança , China , Monitoramento Ambiental/economia , Previsões , Humanos , Indústrias/economia , Medição de Risco
18.
Environ Pollut ; 244: 93-101, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30321715

RESUMO

In this study, a multi-component catalyst, ß-cyclodextrin (ß-CD) and reduced graphene oxide (rGO) co-modified Fe3O4, was fabricated via one-pot solvothermal method and used as a synergistic catalyzer for Bisphenol A (BPA) removal. The study found that catalytic reactions of BPA followed the pseudo-first-order kinetics model, and the correlation rate constants (kobs) were calculated. Compared with Fe3O4@ß-CD (0.02173 min-1), Fe3O4/rGO (0.09735 min-1) and Fe3O4 (0.01666 min-1), the composite (0.15733 min-1) exhibited stronger catalytic ability to remove BPA from aqueous solution under the same conditions, which were attributed to the synergistic enhancement effect among the components. The introduction of rGO in the composites was beneficial to the generation of •OH, and the role of ß-CD might enhance the utilization of •OH. A possible three-element catalytic schematic diagram was described. The effects of pH, dosage of the catalyst, initial H2O2 and NH2OH concentrations on the removal efficiency were further investigated. The removal of BPA and TOC retained 78.2 ±â€¯2.4% and 52.9 ±â€¯2.5% after five cycles, indicating its excellent stability and reusability. Furthermore, a probable reaction pathway of BPA removal was suggested by analyzing the intermediate products. All results indicated that the composite had high and stable catalytic performance, which made it have potential application on the industrial treatment of wastewater.


Assuntos
Compostos Benzidrílicos/química , Catálise , Recuperação e Remediação Ambiental/métodos , Óxido Ferroso-Férrico/química , Grafite/química , Fenóis/química , Fotólise , beta-Ciclodextrinas/química , Peróxido de Hidrogênio/química , Hidroxilamina/química
19.
J Hazard Mater ; 360: 223-232, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30119017

RESUMO

In this research, a novel efficiency MnO2@Nano hollow carbon sphere (MnO2@NHCS) nanocomposite was prepared by one-pot hydrothermal reaction with KMnO4 solution. The adsorption and oxidization performance of MnO2@NHCS were assessed by degradation of bisphenol A (BPA) at different conditions. The effect of dosage of MnO2@NHCS, pH, initial concentration of BPA, temperature and humic acid were investigated systematically. Moreover, the characterizations of MnO2@NHCS were measured by a series of techniques, such as XRD, FESEM, HRTEM, TGA and XPS. Notably, hollow structure of nano carbon sphere was still retained with uniform MnO2 nanosheets covered. The results show that the removal rate of BPA was 95.3% within 10 min and BPA can be almost decomposed in 30 min under the optimal conditions. Additionally, the MnO2@NHCS remained stable and had a high regeneration efficiency (more than 85%) after 3 cycles (360 min). The reaction intermediates/products of oxidation of BPA were analyzed and the possible degradation pathways of BPA were proposed. These research results demonstrate that the MnO2@NHCS is a fleet and efficient material for BPA degradation in aqueous environment.

20.
Sci Total Environ ; 639: 8-18, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29778685

RESUMO

The conventional risk assessment methods may be defective for more effective health risk assessment due to ignoring heavy metal species and the accuracy and integrity of sampling and analysis results. Using the accurate and integral data to quantify the human health effects of metal species can provide great support for more effective health risk assessment. This study presents a new methodology to optimize sampling and analysis results for implementing the spatial human health risk of heavy metal species in contaminated sites. The method integrated Entropy method and Inverse Distance to a Power (IDW) for obtaining the effective risk, and mapping the visual risk distribution of metal species. The results of its application with ingesting arsenic via oral route on adults showed that carcinogenic and non-carcinogenic risks of As were influenced by its species. The risk of HAsO4-2, H3AsO3, H2AsO4-, H2AsO3- and AsS(OH)HS- exceeded threshold that was significantly harmful to human health in study area. This method broadened the scope of human health risk assessment and provided a basis for government policy-making and site remediation.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Adulto , Recuperação e Remediação Ambiental , Humanos , Metais Pesados , Medição de Risco
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