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1.
Sci Total Environ ; 924: 171622, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38467255

RESUMO

Roadway runoff serves as a crucial pathway for transporting contaminants of emerging concern (CECs) from urban environments to receiving water bodies. Tire-related compounds originating from tire wear particles (TWPs) have been frequently detected, posing a potential ecological threat. Yet, the photolysis of tire-related compounds within roadway runoff remains inadequately acknowledged. Addressing this deficit, our study utilized high-resolution mass spectrometry (HRMS) to characterize the chemical profile of roadway runoff across eight strategically selected sites in Guangzhou, China. 219 chemicals were identified or detected within different confidence levels. Among them, 29 tire-related contaminants were validated with reference standards, including hexa(methoxymethyl)melamine (HMMM), 1,3-diphenylguanidine (DPG), dicyclohexylurea (DCU), and N-cyclohexyl-2-benzothiazol-amine (DCMA). HMMM exhibited with the abundance ranging from 2.30 × 104-3.10 × 106, followed by DPG, 1.69 × 104-8.34 × 106. Runoff sample were exposed to irradiation of 500 W mercury lamp for photodegradation experiment. Photolysis results indicated that tire-related compounds with a low photolysis rate, notably DCU, DCMA, and DPG, are more likely to persist within the runoff. The photolytic rates were significantly correlated with the spatial distribution patterns of these contaminants. Our findings underscore TWPs as a significant source of pollution in water bodies, emphasizing the need for enhanced environmental monitoring and assessment strategies.

2.
Environ Sci Pollut Res Int ; 31(13): 20665-20677, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38381288

RESUMO

Micellar-enhanced ultrafiltration (MEUF) technology is an effective method to treat low-concentration heavy metal wastewater. However, the leakage of surfactants in the ultrafiltration (UF) process will inevitably cause secondary pollution. In this study, a biosurfactant of conjugated linoleic acid (CLA) with conjugated double bonds was selected to bind its micelles by simple thermal crosslinking to obtain morphologically stable stearic acid (SA) nanoparticles. The pure SA nanoparticles were obtained by repeated dialysis. The stability of the SA nanoparticles was verified by comparing the particle size distribution and solubility of the materials before and after crosslinking at different pH levels. The effectiveness of SA nanoparticle-enhanced UF in removing heavy metals was verified by exploring the adsorption performance of SA nanoparticles. The dialysis device was used to simplify the UF device, wherein SA nanoparticles were assessed as adsorbents for the elimination of Cu2+, Pb2+, and Cd2+ ions from aqueous solutions under diverse process parameters, including pH, contact time, metal ion concentration, and coexisting ions. The findings indicate that the SA nanoparticles have no evidence of secondary contamination in UF and exhibit compatibility with a broad pH range and coexisting ions. The maximum adsorption capacities for Cu2+, Pb2+, and Cd2+ were determined to be 152.77, 403.56, and 271.46 mg/g, respectively.


Assuntos
Ácidos Linoleicos Conjugados , Metais Pesados , Poluentes Químicos da Água , Cádmio , Micelas , Água , Chumbo , Metais Pesados/química , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética
3.
Chemosphere ; 350: 141082, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38169198

RESUMO

Tributyl phosphate (TNBP), a new type of flame retardant, is an emerging pollutant and has been frequently detected in various matrices such as wastewater. Efficient removal of TNBP is critical for wastewater treatment. In this study, molecularly imprinted polymer (MIP) was prepared using precipitation polymerization for selective adsorption of TNBP. The results showed that MIP had a porous structure and formed effective imprinting cavities, which was primarily responsible for its superior adsorption ability. The adsorption of TNBP by MIP was carried out following both the pseudo-secondary kinetic model and the Langmuir isothermal adsorption model. MIP adsorbed TNBP rapidly and reached adsorption equilibrium within 30 min with 923 µmol g-1 at 298 K. The adsorption capacity and adsorption rate of MIP were respectively 2 and 5.49 times those of non-molecularly imprinted polymers. In addition, MIP could effectively counter disturbances from external parameters like temperature and pH, exhibiting strong environmental flexibility. MIP can specifically adsorb organophosphate esters, and can selectively adsorb TNBP under the interference of coexisting contaminants such as1,3-diphenylguanidine and isazofos. In actual bodies of water, MIP's highly selective adsorption of TNBP retains its advantage. The selective adsorption of MIP was mainly due to the common phosphate skeleton, and the specific substituent of organophosphate esters played an important role in the imprinting process. Hydrogen bonding might be involved in the polymerization process of TNBP with acrylamide and the adsorption process of TNBP by MIP.MIP exhibited good reuse efficiency, the total adsorption capacity decreased by no more than 25% after 7 reuse cycles. This study provides a simple and efficient method for selective removal of organophosphate from wastewater.


Assuntos
Impressão Molecular , Polímeros , Polímeros/química , Águas Residuárias , Água , Adsorção , Organofosfatos , Impressão Molecular/métodos
4.
J Hazard Mater ; 460: 132488, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37696208

RESUMO

Quenching method is widely used to assess the contribution of specified reactive species through the probe inhibition efficiency (IE) caused by adding excessive quencher. However, for reactive species with weak ability such as singlet oxygen (1O2), the quenching results are prone to ambiguity. In this study, an 1O2 system using furfuryl alcohol (FFA) as a probe was successfully constructed by methylene-blue-N vis-photosensitization, to discuss the quenching, interference elimination and pollutant degradation ability of 1O2. Inhibition of FFA transformation caused by both quenching and interrupting of 1O2 production was found. The quenching is affected by quencher dosage and ability, which depends on the second-order-rate constant (k). A high k means a strong ability, and less dosage is required to achieve the same IE. Comparison between the calculated ratio of reactive species consumed by quencher and experimental IE helps to judge the interruption of 1O2 production. None of the organic-solvents (methanol, ethanol, iso-propanol, n-butanol, iso-butanol, tert-butanol, tetrahydrofuran, acetonitrile, acetone and chloroform) scavenged 1O2, which would be used as screening-agent for other reactive species (e.g., hydroxyl radicals) that would interrupt 1O2 contribution assessment. Besides, 1O2 was powerless to degrade most selected pollutants. These results encourage proper use of quenchers and better experimental design.

5.
BMC Cancer ; 23(1): 511, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37277714

RESUMO

BACKGROUND: This study aimed to identify the biological functions, expression modes, and possible mechanisms underlying the relationship between metastatic human hepatocellular carcinoma (HCC) and MicroRNA-188-5p (miR-188) dysregulation using cell lines. METHODS: A decrease in miR-188 was detected in low and high metastatic HCC cells compared to that in normal hepatic cells and non-invasive cell lines. Gain- and loss-of-function experiments were performed in vitro to investigate the role of miR-188 in cancer cell (Hep3B, HepG2, HLF, and LM3) proliferation and migration. RESULTS: miR-188 mimic transfection inhibited the proliferation of metastatic HLF and LM3 cells but not non-invasive HepG2 and Hep3B cells; nonetheless, miR-188 suppression promoted the growth of HLF and LM3 cells. miR-188 upregulation inhibited the migratory rate and invasive capacity of HLF and LM3, rather than HepG2 and Hep3B cells, whereas transfection of a miR-188 inhibitor in HLF and LM3 cells had the opposite effects. Dual-luciferase reporter assays and bioinformatics prediction confirmed that miR-188 could directly target forkhead box N2 (FOXN2) in HLF and LM3 cells. Transfection of miR-188 mimics reduced FOXN2 levels, whereas miR-188 inhibition resulted in the opposite result, in HLF and LM3 cells. Overexpression of FOXN2 in HLF and LM3 cells abrogated miR-188 mimic-induced downregulation of proliferation, migration, and invasion. In addition, we found that miR-188 upregulation impaired tumor growth in vivo. CONCLUSIONS: In summary, this study showed thatmiR-188 inhibits the proliferation and migration of metastatic HCC cells by targeting FOXN2.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo
6.
World J Gastrointest Oncol ; 15(4): 689-699, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37123056

RESUMO

BACKGROUND: Although immune checkpoint inhibitor (ICI) therapy has improved the prognosis of unresectable hepatocellular carcinoma (HCC), it has also resulted in unique immune-related adverse events (irAEs). The relationship between irAE and treatment outcomes in ICI-treated unresectable HCC patients remains unknown. AIM: To elucidate the correlation between immune-related toxic effects and prognosis in patients with unresectable HCC treated with pembrolizumab. METHODS: From March 2019 to February 2021, a total of 190 unresectable HCC (Barcelona Clinic Liver Cancer C) patients receiving pembrolizumab treatment were retrospectively reviewed. Overall survival (OS) was the primary endpoint, while objective response rate (ORR), disease control rate (DCR), and time to progression (TTP) were secondary evaluation indexes. We assessed demographics, irAEs, and outcomes by retrospective review. RESULTS: One hundred and forty-three males and 47 females were included in the study. The ORR and DCR were 12.1% (23/190) and 52.1% (99/190), respectively. The median OS was 376 d [95% confidence interval (CI): 340-411 d] and the median TTP was 98 d (95%CI: 75-124 d). The overall incidence of treatment-related adverse events was 72.6% (138/190) and 10.0% of them were severe irAEs (grade ≥ 3). Child-Pugh B class, portal vein tumor thrombus, extrahepatic metastasis, and hypothyroidism were the independent risk factors for survival. Patients with hypothyroidism showed a longer OS [517 d (95%CI: 423-562) vs 431 d (95%CI: 412-485), P = 0.011] and TTP [125 d (95%CI: 89-154) vs 87 d (95%CI: 61-98), P = 0.004] than those without irAEs. CONCLUSION: Pembrolizumab-treated patients with unresectable HCC who experienced hypothyroidism have promising ORR and durable response. Hypothyroidism, an irAE, may be used as a clinical evaluation parameter of response to ICIs in unresectable HCC.

7.
Chemosphere ; 334: 138990, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37209856

RESUMO

Soil washing techniques can effectively remove soil polybrominated diphenyl ethers (PBDEs), but further removal of PBDEs from washing effluent is disrupted by environmental factors and coexisting organic matter. Hence, this work prepared novel magnetic molecularly imprinted polymers (MMIPs) to selectively remove PBDEs in soil washing effluent and recycling surfactants, with Fe3O4 nanoparticles as the magnetic core, methacrylic acid (MAA) as the functional monomer, and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. Later, the prepared MMIPs were applied to adsorb 4,4'-dibromodiphenyl ether (BDE-15) in Triton X-100 soil-washing effluent and characterized by scanning electron microscopy (SEM), infrared spectrometry (FT-IR), nitrogen adsorption and desorption experiments. According to our observations, BDE-15 equilibrium adsorptions on dummy-template magnetic molecularly imprinted adsorbent (D-MMIP, 4-bromo-4'-hydroxyl biphenyl as template) and part-template magnetic molecularly imprinted adsorbent (P-MMIP, toluene as template) were reached within 40 min, and their equilibrium adsorption capacities were 164.54 µmol/g and 145.55 µmol/g, respectively, with imprinted factor α > 2.03, selectivity factor ß > 2.14, and selectivity S > 18.05. MMIPs exhibited good adaptability to pH, temperature, and cosolvent. Our Triton X-100 recovery rate reached as high as 99.9%, and MMIPs maintained a more than 95% adsorption capacity after being recycled five times. Our results offer a novel approach to selectively remove PBDEs in soil-washing effluent, with efficient recovery of surfactants and adsorbents in soil-washing effluent.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Éteres Difenil Halogenados , Impressão Molecular/métodos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Octoxinol , Adsorção , Fenômenos Magnéticos
8.
Front Surg ; 10: 1097327, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36936662

RESUMO

Background: An increased risk of gallstones has been observed in patients undergoing hepatectomy. This study attempted to analyze the risk factors for gallstones after hepatectomy. Methods: From January 2013 to December 2016, clinical data of 1,452 eligible patients who underwent hepatectomy were consecutively reviewed. According to the imaging, including gallbladder ultrasound, computerized tomography, and magnetic resonance imaging, all patients were divided into the gallstone group and the nongallstone group. Univariate and multivariate logistic regression analyses were performed to select indicators associated with gallstone formation among patients after hepatectomy. Results: In the total sample of included patients, there were 341 patients with gallstones and 1,147 patients without gallstones. The incidence of gallstones was 23.5% (341/1,452). The incidence of gallstones in the primary liver cancer group was higher than that in the benign liver tumor group (25.7% vs. 18.9%, P = 0.004). Univariate and multivariate logistic regression analyses showed that female gender, high body mass index, tumor located in S5, and severe postoperative complication were factors related to gallstones in patients with benign liver tumors after hepatectomy. In addition, Child-Pugh B, low albumin, liver cirrhosis, and transcatheter arterial chemoembolization (TACE) after recurrence were factors related to gallstones in patients with primary liver cancer after hepatectomy. Conclusions: Hepatectomy increased the risk of gallstones in benign or malignant liver tumors, especially when the tumor was located in S5. TACE further increased the risk of gallstones in patients with postoperative recurrence.

9.
Chemosphere ; 325: 138396, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36931399

RESUMO

Polybrominated diphenyl ethers (PBDEs) as a typical brominated flame retardant (BFR) have attracted worldwide attention due to the high environmental risk and resistance to conventional remediation processes. In this study, thermally activated persulfate (TAP) process was applied to degrade 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), which is the most toxic and representative PBDEs in e-waste dismantling sites. Impact factors such as PDS dosage, heating temperature, and initial pH were evaluated. Results showed that BDE-47 can be 100% degraded within 180 min under the condition of PDS:BDE-47 = 1000:1, 60 °C, and pH = 7. Quenching experiments combined with EPR analysis further proved the important role of SO4·- in oxidating BDE-47. According to high-resolution mass spectrometry (HRMS) analysis, only one oxidation product of low toxicity was detected during the oxidation process. Theoretical calculations further revealed that the oxidation process mainly involved radical attack at C-Br bond, cleavage of C-Br bond, and fission of ether bond, and HSO4· may also play an important role in BDE-47 degradation in TAP system. In addition, TAP system exhibited universality as all selected PBDE congeners can be degraded, and the degradation rate of PBDEs was greatly affected by the number of substituted Br atoms in a negative trend. Overall, these findings indicate that TAP can be applied as an effective method for removal of PBDEs, and we provide a new insight for the practical application of TAP technology in BDE-47 degradation from experimental and theoretical aspects.


Assuntos
Retardadores de Chama , Éteres Difenil Halogenados , Éteres Difenil Halogenados/análise , Éter , Etil-Éteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Retardadores de Chama/análise
10.
J Environ Sci (China) ; 129: 45-57, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36804241

RESUMO

Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils. The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions. In this study, a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers (PBDEs) in soil washing effluent. The novel molecular imprinted polymers (MIPs) using different template molecules were synthesized by precipitation polymerization. Adsorption behaviors and mechanisms of MIPs were studied through experiments and theoretical calculations. The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis. The maximal adsorption capacity of selected dummy molecular imprinted polymer (D1-MIP) was 1032.36 µmol/g, and that of part molecular imprinted polymer (P-MIP) was 981.13 µmol/g. Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88, the recovery percentage of Triton X-100 can reach 99.09%, confirming the feasibility of reusing surfactant. Various PBDEs could be removed by MIPs, and Quantitative Structure Property Relationship analysis revealed that PBDEs' molecular volume, planarity, polarity, and hydrophobicity have major influences on their adsorption performance. DFT calculation revealed that Van der Waals force and hydrogen bonding played important roles during selective adsorption. These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.


Assuntos
Poluentes Ambientais , Impressão Molecular , Éteres Difenil Halogenados , Impressão Molecular/métodos , Polímeros/química , Tensoativos , Adsorção
11.
Environ Res ; 219: 115128, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563975

RESUMO

Tris(2-chloroethyl) phosphate (TCEP) as a new type of flame retardant exists in various water environments, causing great risks to humans and the environment. In this study, shrimp shell was used to prepare an economical and environmental-friendly adsorbent for the efficient removal of TCEP. The systematic studies including characterization, removal performance, and adsorption mechanism of shrimp shell biochar toward TCEP were carried out. Adsorption kinetics and thermodynamics showed that fast equilibrium reached within 30 min, the maximum adsorption capacity qm was 108 µmol g-1 at 298 K, and the adsorption process is spontaneous and exothermic. The environmental factor, such as temperature, pH, inorganic anions and organic matter hardly affected the adsorption performance. Structural characterization indicated that the hierarchical porous structure of shrimp shell biochar is the key to excellent adsorption performance. The adsorption mechanisms were further revealed using density functional theory (DFT) calculations, and the hydrogen bond, van der Waals interactions, Cl-H interactions, and pi-H interactions were identified as potential interaction mechanisms between TCEP and specific biochar structures. The calculated binding energy between TCEP and simplified biochar structure suggested that oxygen-containing groups especially carboxyl, hydroxyl and aldehyde facilitate the adsorption. Our work not only provides a novel strategy for the quick remediation of organophosphate-contaminated water environments but also offers new opportunities for crustacean waste biomass valorization.


Assuntos
Organofosfatos , Poluentes Químicos da Água , Humanos , Adsorção , Teoria da Densidade Funcional , Porosidade , Fosfatos , Água , Cinética
12.
Sci Total Environ ; 861: 160563, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36455747

RESUMO

During the past decade, the characterization of microbial community in soil of contaminated sites was primarily done by high-throughput short-read amplicon sequencing. However, due to the similarity of 16S rRNA and ITS genes amplicon sequences, the short-read approach often limits the microbial composition analysis at the species level. Here, we simultaneously performed full-length and short-read amplicon sequencing to clarify the community composition and ecological status of different microbial taxa in contaminated soil from a high-resolution perspective. We found that (1) full-length 16S rRNA gene sequencing gave better resolution for bacterial identification at all levels, while there were no significant differences between the two sequencing platforms for fungal identification in some samples. (2) Abundant taxa were vital for microbial co-occurrences network constructed by both full-length and short-read sequencing data, and abundant fungal species such as Mortierella alpine, Fusarium solani, Mrakia frigida, and Chaetomium homopilatum served as the keystone species. (3) Heavy metal correlated with the microbial community significantly, and bacterial community and its abundant taxa were assembled by deterministic process, while the other taxa were dominated by stochastic process. These findings contribute to the understanding of the ecological mechanisms and microbial interactions in site soil ecosystems and demonstrate that full-length sequencing has the potential to provide more details of microbial community.


Assuntos
Microbiota , Solo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Filogenia , Microbiota/genética
13.
Chemosphere ; 313: 137501, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36502914

RESUMO

The development of efficient, environmentally friendly soil amendments is necessary in order to minimize the risk of metal contaminants (Cd, Pb, Cu, and Zn) to the soil ecosystem. As soil amendments, bovine bone meal (BM) and oyster shell meal (OS) reduced the mobility and bioavailability of metals primarily by increasing soil pH. Soil geochemical properties (pH, EC, CEC, Ca, P, and K) after amendment supplementation were more likely to affect metal migration than enzyme activity. Furthermore, BM and OS were found to suppress the Cd and Pb uptake by water spinach, keeping them below international standards for safe utilization. The protein and sugar content and peroxidase (POD) activity showed a significant negative correlation with the amount of metal in water spinach, whereas superoxide dismutase (SOD), ascorbate peroxidase (APX) activities and malondialdehyde (MDA) content exhibited a positive correlation with metal content in water spinach. We also found that BM and OS had less perturbation to phylum-level and genus-level bacterial composition during the remediation of heavy metals contaminated soil. Based on the above, we assume that BM and OS are eco-friendly soil amendments, which could improve soil nutrients contents, stabilize heavy metals and regulate bacterial community structure. Our research contributes to resource utilization of waste and holds promise for widespread application in current agricultural systems.


Assuntos
Metais Pesados , Ostreidae , Poluentes do Solo , Animais , Bovinos , Solo/química , Cádmio/metabolismo , Verduras/metabolismo , Ecossistema , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Carbonato de Cálcio , Bactérias/metabolismo , Ostreidae/metabolismo
14.
Chemosphere ; 308(Pt 1): 136246, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36044966

RESUMO

This study presents the comprehensive investigation for formation pathways of chloro-bromo-mixed products from the pyrolysis of polybrominated diphenyl ethers (PBDEs). In the study, a total of 23 PBDEs with bromination levels from mono-to deca-were selected. Each PBDE standard was sealed in the glass vial and then heated under 450 °C in the muffle furnace to simulate the pyrolysis process. The results demonstrated that PBDEs in the glass vials can unintentionally transform into chloro-bromo diphenyl ethers (PBCDEs) and dibenzo-p-dioxin and dibenzofurans (PBCDD/Fs) during the pyrolysis process. Atmosphere pressure gas chromatography (APGC) coupled with high-resolution mass spectrometry (HRMS) was used to identify these pyrolysis products, which demonstrated that all investigated nPBDEs (n represents the number of bromine substituents) can unintentionally transform into Cl1-(n-1)BDEs, Cl2-(n-2)BDEs, Cl1-(n-1)BDFs, and Cl1-(n-3)BDDs, while some nPBDEs can transform into Cl1-(n-2)PBDD/Fs during pyrolysis. Experimental phenomena assisted with density functional theory (DFT) calculations reveal that Cl atom can substitute at C-Br rather than C-H, and Cl1-(n-1)BDEs can be easily generated by Cl atom attacking at C-Br sites with low energy barriers (3.66-11.9 kcal/mol). In addition, nPBDEs with lower bromination levels are more favorable to generate Cl1-(n-1)BDEs than those with higher bromination levels. Further DFT calculations suggest that PBDEs are preferentially first transformed into Cl1-(n-1)BDEs, then subsequentially transform into PBCDD/Fs. We believe the results of this study can greatly improve our understanding of the transformation mechanism from PBDEs to cholo-bromo-mixed products in thermal treatment processes and provide new insight into controlling the emission of toxic cholo-bromo-mixed products.


Assuntos
Dibenzofuranos , Éteres Difenil Halogenados , Bromo/química , Dibenzofuranos/análise , Dioxinas , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/análise , Pirólise
15.
Sci Total Environ ; 832: 155142, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35405241

RESUMO

CaCO3 filler masterbatch (CFM) is one of the most commonly used fillers in polypropylene (PP) and polyethylene (PE) products, and its is used to enhance the toughness of the polymer matrix. This is the first study to investigate the loss of CaCO3 and its impact on the adsorption ability of microplastics from plastic woven bags throughout the natural aging process. PP wire (PPw, 85% PP + 15% CFM) and PE film (PEf, 80% PE + 20% CFM) samples from plastic woven bags underwent a 250 d aging process in an open-air environment. Changes in the surface properties, morphology, CaCO3 content, and density of PPw microplastics (PPw-MP) and PEf microplastics (PEf-MP) after various durations of aging were investigated by scanning electron microscopy, infrared spectroscopy, and thermogravimetric analysis. The results showed that CaCO3 separated and agglomerated on the surfaces of PPw-MP and PEf-MP after 30 d. After 250 d, 42% of CaCO3 was lost from PPw-MP and 28% was lost from PEf-MP, decreasing the density of the microplastic samples. CFM presented a considerably higher adsorption affinity toward Cu(II) than PP particles and PE particles; therefore, its presence in plastic matrix increased the adsorption ability of the products. The adsorption of Cu(II) on PPw-MP and PEf-MP decreased with aging because of the loss of CaCO3 and poor development of O-containing functional groups. The qm value (maximum adsorption quantity of Langmuir model) decreased from 11.01 mg/g in unaged PPw-MP to 1.35 mg/g in aged PPw-MP, and from 9.00 mg/g in unaged PEf-MP to 1.05 mg/g in aged PEf-MP. Overall, the findings demonstrate that CaCO3 was crucial for the heavy metal-plastic interactions of the samples. Therefore, the results provide a basis to further clarify the potential environmental risks of plastic woven bags associated with heavy metal mobility.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Carbonato de Cálcio , Metais Pesados/análise , Microplásticos , Plásticos/química , Polipropilenos , Poluentes Químicos da Água/análise
16.
Medicine (Baltimore) ; 100(4): e24326, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33530224

RESUMO

ABSTRACT: The spleen plays an important role in tumor progression and the curative effects of splenectomy before hepatectomy for hypersplenism and hepatocellular carcinoma (HCC) are not clear. We investigated whether splenectomy before hepatectomy increases survival rate among patients with HCC and hypersplenism compared with that of patients who underwent synchronous hepatectomy and splenectomy or hepatectomy alone.Between January 2011 and December 2016, 266 patients who underwent hepatectomy as a result of HCC and portal hypertension secondary to hepatitis were retrospectively analyzed. Their perioperative complications and survival outcome were evaluated.Patients underwent synchronous hepatectomy and splenectomy (H-S group) and underwent splenectomy before hepatectomy (H-preS group) exhibited significantly higher disease-free survival (DFS) rates than those of patients underwent hepatectomy alone (H-O group). The DFS rates for patients in the H-S group, H-preS group, and H-O group were 74.6%, 48.4%, 39.8%, and 80.1%, 54.2%, 40.1%, and 60.5%, 30.3%, 13.3%, at 1, 3, and 5 years after surgery, respectively. Tumor size, tumors number, and levels of alpha fetoprotein (AFP) were independent risk factors for DFS. Gender and tumor size were independent prognostic factor for overall survival (OS). The preoperative white blood cell (WBC) and platelet (PLT) counts were significantly higher in the H-preS group than in those of the H-S group and the H-O group. After operation, the WBC and PLT counts in the H-S group and H-preS groups were significantly higher compared to those of the H-O group.No matter splenectomy before hepatectomy or synchronous hepatectomy and splenectomy, hepatectomy with splenectomy may improve DFS rates in patients with HCC and hypersplenism, and splenectomy before hepatectomy alleviates hypersplenism without an increased surgical risk.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/mortalidade , Hiperesplenismo/cirurgia , Neoplasias Hepáticas/cirurgia , Esplenectomia/mortalidade , Adulto , Biomarcadores/sangue , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Terapia Combinada , Intervalo Livre de Doença , Feminino , Hepatectomia/métodos , Humanos , Hiperesplenismo/complicações , Hiperesplenismo/mortalidade , Contagem de Leucócitos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Estudos Retrospectivos , Esplenectomia/métodos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , alfa-Fetoproteínas/análise
17.
Ecotoxicology ; 30(2): 231-239, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33483874

RESUMO

Chromium (Cr) pollution in farmlands is a common environmental issue, that can seriously inhibit plant growth, damage plant cells, and even cause plant death. In this study, bok choy (Brassica campestris L. ssp. chinensis Makino (var. communis Tsen et Lee)) was selected as a model plant to investigate the metabolic response to Cr stress at concentrations of 2.0 mg/L and 8.0 mg/L. Metabolites were identified using gas chromatography-mass spectrometry. Principal component analysis and orthogonal projections to latent structure discriminant analysis revealed the notable effect of Cr stress on the metabolites of bok choy. Under Cr stress, 145 metabolites were identified in the bok choy leaves. At 2.0 mg/L Cr stress, 10 and 26 metabolites changed compared to the control after 7 d and 14 d, respectively. At 8.0 mg/L Cr stress, 24 and 24 metabolites changed significantly after 7 and 14 d, respectively. The data showed that metabolism was affected by the Cr stress concentration and exposure time. Specifically, under the Cr stress, the tricarboxylic acid cycle, glutamine synthetase/glutamate synthase cycle, and partial amino acid metabolic pathways were blocked, inhibiting the normal growth and development of bok choy. The change of citric acid content was the most significant, and the accumulation of citric acid indicated the degree of plant Cr toxicity and resistance. These results would facilitate further dissection of the mechanisms of heavy metal accumulation/tolerance in plants and the effective management of such contamination in vegetable crops by genetic manipulation.


Assuntos
Brassica , Metais Pesados , Poluentes do Solo , Cromo/toxicidade , Poluição Ambiental , Metais Pesados/análise , Folhas de Planta/química , Poluentes do Solo/análise
18.
World J Gastrointest Oncol ; 13(12): 2190-2202, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35070051

RESUMO

BACKGROUND: The long-term effect of anatomic resection (AR) is better than that of non-anatomic resection (NAR). At present, there is no study on microvascular invasion (MVI) and liver resection types. AIM: To explore whether AR improves long-term survival in patients with hepatocellular carcinoma (HCC) by removing the peritumoral MVI. METHODS: A total of 217 patients diagnosed with HCC were enrolled in the study. The surgical margin was routinely measured. According to the stratification of different tumor diameters, patients were divided into the following groups: ≤ 2 cm group, 2-5 cm group, and > 5 cm group. RESULTS: In the 2-5 cm diameter group, the overall survival (OS) of MVI positive patients was significantly better than that of MVI negative patients (P = 0.031). For the MVI positive patients, there was a statistically significant difference between AR and NAR (P = 0.027). AR leads to a wider surgical margin than NAR (2.0 ± 2.3 cm vs 0.7 ± 0.5 cm, P < 0.001). In the groups with tumor diameters < 2 cm, both AR and NAR can obtain a wide surgical margin, and the surgical margins of AR are wider than that of NAR (3.5 ± 5.8 cm vs 1.6 ± 0.5 cm, P = 0.048). In the groups with tumor diameters > 5 cm, both AR and NAR fail to obtain wide surgical margin (0.6 ± 1.0 cm vs 0.7 ± 0.4 cm, P = 0.491). CONCLUSION: For patients with a tumor diameter of 2-5 cm, AR can achieve the removal of peritumoral MVI by obtaining a wide incision margin, reduce postoperative recurrence, and improve prognosis.

19.
BMC Cancer ; 20(1): 1047, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129301

RESUMO

BACKGROUND: This study explored the diagnostic power of preoperative circulating tumor cells (CTCs) for the presence of microvascular invasion (MVI) and the relationship between dynamic changes in postoperative CTCs and prognosis. METHODS: A total of 137 patients were recruited for the study. Preoperative blood samples were collected from all patients to detect CTCs. The time points for blood collection were before the operation, during the operation, and at 1 week, 1 month, 2 months, 3 months, 6 months, and 1 year after surgery. The predictive power of CTC count for the presence of MVI was analyzed by receiver operating characteristic (ROC) curve analysis. According to recurrence status, 137 patients were divided into three groups: no recurrence, early recurrence, and non-early recurrence groups. RESULTS: A threshold CTC count of 5 showed the most significant power for predicting the existence of MVI. In multivariate analysis, the parameters of preoperative CTC count, alpha-fetoprotein (AFP) and tumor diameter were independent predictors of MVI (P <  0.05). A CTC count greater than or equal to 5 had better predictive value than AFP > 400 µg/L and tumor diameter > 5 cm. The number of intraoperative CTCs in the three groups did not increase compared to that before surgery (P > 0.05). The number of CTCs in the nonrecurrence group and the non-early recurrence group decreased significantly 1 week after surgery compared with the intraoperative values (P <  0.001), although there was no significant difference in the early recurrence group (P = 0.95). Patients with mean CTC count ≥5 had significantly worse long-term outcomes than those with mean CTC count < 5 (P <  0.001). CONCLUSION: The preoperative CTC counts in the peripheral blood of patients with HCC are closely correlated with MVI. The intraoperative manipulation of the lesion by the surgeon does not increase the number of CTCs in peripheral blood. Surgical removal of the tumor decreases the number of CTCs. The persistence of CTCs at a high level (≥ 5) after surgery suggests a risk of early recurrence. CLINICAL TRIAL REGISTRATION: Registration number is ChiCTR-OOC-16010183 , date of registration is 2016-12-18.


Assuntos
Carcinoma Hepatocelular/patologia , Hepatectomia/métodos , Neoplasias Hepáticas/patologia , Microvasos/patologia , Recidiva Local de Neoplasia/patologia , Células Neoplásicas Circulantes/patologia , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem
20.
Water Sci Technol ; 80(6): 1076-1084, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31799951

RESUMO

In this study, starch-stabilized nanoscale zero-valent iron (S-nZVI) was produced using the liquid-phase reduction method. It was used to remove chromium from wastewater, and compared to a commercial nanoscale zero-valent iron (C-nZVI). Both nZVIs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The characterization results showed that S-nZVI had smaller particles and a more uniform particle size distribution than C-nZVI. Both nZVIs showed a core-shell structure with the Fe0 core prominently surrounded by less iron oxides of Fe2+ and Fe3+. The optimal application methods to remove Cr(VI) from wastewater were also explored. The results showed that both the removal efficiencies of total Cr and Cr(VI) increased with increases in the addition of nZVIs, while the removal efficiencies of total Cr and Cr(VI) by S-nZVI were clearly higher than that of C-nZVI, especially in a low pH range (pH = 1.0-6.0). This research indicated that starch-stabilized nanoscale zero-valent iron is a valuable material to remove heavy metals from wastewater due to its stability and high reactivity.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Cromo , Ferro , Amido
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