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2.
Environ Pollut ; 337: 122562, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37717896

RESUMO

The electroplating industry encompasses various processes and plating types that contribute to environmental pollution, which has led to growing public concern. To investigate related soil pollution in China, the study selected 10 sites with diverse industrial characteristics distributed across China and collected 1052 soil samples to determine the presence of industrial priority pollutants (PP) based on production process and pollutant toxicity. The factors influencing site pollution as well as proposed pollution prevention and control approaches were then evaluated. The results indicate the presence of significant pollution in the electroplating industry, with ten constituents surpassing the risk screening values (RSV). The identified PP consist of Cr(VI), zinc (Zn), nickel (Ni), total chromium (Cr), and petroleum hydrocarbons (C10-C40). PP contamination was primarily observed in production areas, liquid storage facilities, and solid zones. The vertical distribution of metal pollutants decreased with soil depth, whereas the reverse was true for petroleum hydrocarbons (C10-C40). Increase in site production time was strongly correlated with soil pollution, but strengthening anti-seepage measures in key areas can effectively reduce the soil exceedance standard ratio. This study serves as a foundation for conceptualizing site repair technology in the electroplating industry and offers a reference and methodology for pollution and source control in this and related sectors.


Assuntos
Poluentes Ambientais , Metais Pesados , Petróleo , Poluentes do Solo , Metais Pesados/análise , Galvanoplastia , Poluentes do Solo/análise , Medição de Risco , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Poluentes Ambientais/análise , Cromo/análise , Solo , China , Hidrocarbonetos/análise , Petróleo/análise
3.
J Hazard Mater ; 448: 130892, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36758430

RESUMO

Accurate quantification of arsenic migration and accumulation in brownfield site is critical for environmental management and soil remediation. However, the researches simulating arsenic in brownfield site in China are limited due to sparse data and complex migration behaviors. In this study, we simulated historic arsenic contamination using Hydrus-3D in an abandoned brownfield site in Hebei, China, from 1972 to 2019. Atmospheric discharge, wastewater leakage, solid waste discharge and tank leakage were calculated according to the factory processes for model simulation. Based on the results of Hydrus-3D, we assessed health risk of arsenic in this site. The results showed that total arsenic input to the soil surface from 4 pathways was 24.6 tons, the solid waste discharge was the highest contributor. The accumulation process mainly occurred in the unsaturated zone due to clay and silty clay absorbed arsenic and thus slow down the migration process. While in the saturation zone, abundant groundwater promoted migration of arsenic, resulting in widespread distribution of contaminated area. The model results represented good performance between simulated and measured values. Sensitivity analysis indicated that adsorption constant and water conductivity were the most influential parameters. Heath risk assessment showed that arsenic contamination continues to threaten resident health.

4.
RSC Adv ; 13(4): 2707-2717, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36741169

RESUMO

Carbonyl cyanide p-nitrophenylhydrazone (2e) displayed a lone or synergistic efficacy against MRSA (RSC Adv., 2020, 10, 17854). In this work, the synergistic mechanism of 2e with ofloxacin was studied. MRSA2858 had potential for biofilm formation, and the value of MBEC of 2e alone was 0.78-1.56 µM, while that of 2e + ofloxacin was 0.39-0.78 µM. 2e combined with ofloxacin showed a synergistic anti-biofilm effect against MRSA. Efflux pump inhibitor 2e can better bind to NorA protein. After MRSA2858 was treated with 2e of 1/2MIC (0.78 µM) and ofloxacin of 1/8MIC (0.097 µM), the transcript levels of efflux genes (norA) and quorum-sensing (QS) regulatory genes (agrA, sarA, icaA, hla) were substantially down-regulated, and alpha-hemolysin (Hla) was inhibited by 99.15%. 2e combined with ofloxacin was more effective than 2e alone in reducing bacterial load in vivo. All in all, efflux pump inhibitor 2e enhanced the bactericidal activities of antibiotics through regulating the gene expression of NorA and QS system.

5.
Chem Biodivers ; 20(2): e202200899, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36631282

RESUMO

BACKGROUND: Flavonoid glycosides are known to possess diverse bioactivities including antitumor and anti-inflammatory properties. Hesperetin is abundant in nature and can be used to synthesize bioactive flavonoids. This has the advantages of low cost, short synthetic steps, simple operation, and good yields. OBJECTIVE: In this study, we aimed to synthesize bioactive flavonoids and flavonoid glycosides from hesperetin and evaluate the antitumor and anti-inflammatory activities of these compounds. METHODS: A series of flavonoids and their derivatives were synthesized by methoxylation, oxidative dehydrogenation, benzylation, debenzylation, and deacetylation as well as using a modified peroxyacetone method and a glycoside condensation reaction. Their anti-inflammatory activities were evaluated for their inhibitory effects on nitric oxide (NO), tumor necrosis factor (TNF-α), and interleukin-6 (IL-6) production in LPS-induced RAW264.7 mouse macrophages. Their structures were characterized by HRMS, 1 H-NMR, and 13 C-NMR, and their cytotoxicity on the human triple-negative breast cancer cell (TNBC) line, SUM 149, was tested by using the MST assay. RESULTS: Most of the compounds markedly reduced NO production in LPS-stimulated murine macrophages at the tested concentrations in a dose-dependent manner. Among these, compounds 1, 7, 9, and 17 showed significant anti-inflammatory activities against NO production in LPS-induced RAW264.7 mouse macrophages. In addition, they could also reduce the release of TNF-α and IL-6 in a concentration-dependent manner. Most of the tested compounds showed remarkable anti-human TNBC activities. Compounds 1b-1m, 1, and 3 showed a certain degree of growth inhibition effect on the human TNBC cell lines and their IC50 values were all below 16.61 µM. In addition, compound 1l was the most cytotoxic with IC50 values of 1.38±0.31 µM, while the other compounds were inactive with inhibition rates <50 % at the highest concentration tested (20 µM). CONCLUSIONS: A novel series of flavonoids were synthesized from the natural flavonoid, hesperetin, including 17 new compounds. Screening tests indicated that most of these compounds reduced NO production in LPS-stimulated murine macrophages at concentrations of 15 to 60 µM, and the inhibition generally increased in a dose-dependent manner. Some compounds showed different degrees of cytotoxicity on the human TBNC cell lines, SUM 149.


Assuntos
Flavonoides , Neoplasias de Mama Triplo Negativas , Camundongos , Animais , Humanos , Flavonoides/química , Glicosídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/farmacologia , Óxido Nítrico
6.
Ecotoxicol Environ Saf ; 242: 113858, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35809393

RESUMO

Carbon nanotubes (CNTs) have become far and wide used in a number of technical and merchant applications as a result of substantial advances in nanotechnology, therein single-walled carbon nanotubes (SWCNT) are one of the most promising nanoparticles. Inhaling CNTs has been linked to a variety of health problems, including lung fibrosis. Glycyrrhetinic acid 3-O-mono-ß-D-glucuronide (GAMG), a natural sweetener, has anti-inflammatory and antioxidant capacities. The purpose of this study was to evaluate the potential for GAMG to alleviate SWCNT-induced lung inflammation and fibrosis. During days 3-28 after SWCNT intratracheal administration, we observed a remarkable increase of IL-1ß, IL-6 and TNF-α in bronchoalveolar lavage fluid (BALF) on day 3 and collagen deposition on day 28. GAMG treatment remarkably ameliorated SWCNT-induced pulmonary fibrosis and attenuated SWCNT-induced inflammation and collagen deposition, and suppressed the activation of PI3K/AKT/NF-κB signaling pathway in the lungs. Therefore, GAMG has a therapeutic potential for the treatment of SWCNT-induced pulmonary fibrosis. Targeting PI3K/AKT/NF-κB signaling pathway may be a potential therapeutic approach to treat pulmonary fibrosis in mice with SWCNT.


Assuntos
Ácido Glicirretínico , Nanotubos de Carbono , Pneumonia , Fibrose Pulmonar , Animais , Colágeno/metabolismo , Fibrose , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/metabolismo , Ácido Glicirretínico/toxicidade , Pulmão/metabolismo , Camundongos , NF-kappa B/metabolismo , Nanotubos de Carbono/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Pneumonia/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Transdução de Sinais
7.
Eur J Med Chem ; 236: 114333, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35397402

RESUMO

Novel benzothiazole‒urea hybrids were designed, synthesized and evaluated their anti-bacterial activity. They only exhibited anti-bacterial activity against Gram-positive bacteria, including clinical methicillin-resistant S. aureus (MRSA), compounds 5f, 5i, 8e, 8k and 8l exhibited potent activity (MIC = 0.39 and 0.39/0.78 µM against SA and MRSA, respectively). Crystal violet assay showed that compounds 5f, 8e and 8l not only inhibited the formation of biofilms but also eradicated preformed biofilms. Compound 8l had membrane disruption, little propensity to induce resistance, benign safety and in vivo anti-MRSA efficacy in a mouse model of abdominal infection. Therefore, our data demonstrated the potential to advance benzothiazole‒urea hybrids as a new class of antibiotics.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/química , Bactérias , Benzotiazóis/farmacologia , Biofilmes , Camundongos , Testes de Sensibilidade Microbiana , Ureia
8.
ACS Omega ; 7(7): 5937-5945, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35224354

RESUMO

Chitosan is a typical hydrophilic biomass building block widely used in material science and engineering. However, its intrinsic amphiphilicity has been seldom noted so far. Herein, a series of glutaraldehyde-crosslinked chitosan cryogels with superamphiphilicity are fabricated at moderately frozen conditions through a freezing-thawing process. The micron-sized porous cryogel samples display a 0° contact angle toward both water and oil, 0° water contact angle under oil, and over 120° oil contact angle underwater. By comparing the wetting behavior of the tablet compressed by pure chitosan powders, the superamphiphilicity of the chitosan sample is proven to be independent on crosslinkers. This special wettability endows the chitosan cryogels with high separation efficiency for various surfactant-stabilized oil-in-water emulsions under continuous flow mode driven by gravity as well as a peristaltic pump.

9.
Front Microbiol ; 13: 1071255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590419

RESUMO

Enterococcus faecium (E. faecium) is a clinical multidrug-resistant pathogen causing life-threatening infection, which makes it important to discover antibacterial agents with novel scaffolds and unique mechanism. In this study, the diarylurea scaffold was found to have potent antibacterial effect on E. faecium. Diarylurea ZJ-2 with benign drug-like property exhibited potent antibacterial and anti-biofilm activity through inhibiting the genes expression of NlpC/p60 hydrolase-secreted antigen A (sagA) and autolysins (atlA), down-regulating the expression of biofilm adherence related genes aggregation substance (agg), enterococcal surface protein (esp) against E. faecium. Moreover, ZJ-2 can be docked into SagA to inhibit daughter cell separation. In a mouse model of abdominal infection, ZJ-2 decreased the bacterial load and the level of IL-6 and TNF-α in a time-dependent manner. Overall, these findings indicated that diarylurea ZJ-2 has the potential to be developed as a therapeutic agent to treat drug-resistant enterococci and biofilm-related infections.

10.
Asian J Androl ; 24(5): 509-512, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34747726

RESUMO

The aim of this study was to investigate the incidence of erectile dysfunction (ED) in nonmuscle-invasive bladder cancer (NMIBC) patients before and after transurethral resection (TUR) in China. Clinical data from 165 male patients with NMIBC who received adjuvant intravesical chemotherapy after TUR in Neijiang First People's Hospital (Neijiang, China) between January 2010 and June 2019 were retrospectively reviewed. The sexual function of these patients was evaluated before and 1.5 years after initial TUR by the International Index of Erectile Function-5 (IIEF-5). An age-specific subanalysis was performed among the patients: <45 years old (Group 1, n = 19) and ≥45 years old (Group 2, n = 146). Before and 1.5 years after TUR, the incidence rates of ED in Group 1 were 15.8% and 52.6%, and those in Group 2 were 54.1% and 61.0%, respectively. The difference between groups was statistically significant at the preoperative stage (15.8% vs 54.1%, P = 0.002) but not at the postoperative stage (52.6% vs 61.0%, P = 0.562). Compared with the preoperative stage, the incidence of ED at the postoperative stage was increased significantly in Group 1 (15.8% vs 52.6%, P = 0.017) but not in Group 2 (54.1% vs 61.0%, P = 0.345). In conclusion, the incidence of ED increased in male NMIBC patients under the age of 45 years after TUR in China. These patients should be offered professional counseling during the follow-up period.


Assuntos
Disfunção Erétil , Neoplasias da Bexiga Urinária , Administração Intravesical , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos
11.
Bioorg Med Chem Lett ; 54: 128444, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34763082

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer. Many studies have shown a significant increase in the marker signal of the receptor for advanced glycation end-products (RAGE) with the malignant progression of tumor growth, metastasis and recurrence of breast cancer, including TNBC of primary tumors and lymph node metastases. Azeliragon is a RAGE inhibitor and it has been shown to actively inhibit the TNBC cell line, SUM149 (IC50 = 5.292 ± 0.310 µM). In order to develop a new anti-TNBC agent, we designed, synthesized and screened 26 Azeliragon triazole analogues to determine their anti-TNBC activities in vitro. The most active compound was KC-10 with an IC50 value of 0.220 ± 0.034 µM.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Imidazóis/farmacologia , Triazóis/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Imidazóis/síntese química , Imidazóis/química , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Neoplasias de Mama Triplo Negativas/patologia
12.
Food Sci Nutr ; 9(8): 4431-4439, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34401091

RESUMO

Traditional methods for the determination of starch aging indicators often have a series of shortcomings such as time-consuming, high cost, large human error, damage to samples, environmental pollution, and high requirements for inspectors. Therefore, it is meaningful to find or establish a dynamic fingerprint identification pattern that can detect the aging degree of starch during the process of processing or storage quickly and accurately. It not only provides guidance for starch food processing but also saves a lot of human, material resources, and time. Terahertz technology is an emerging molecular spectroscopy technology in the 21st century. It is with low energy and basically harmless to the human body. It can also realize nondestructive testing of samples. In the experiment, the samples were prepared by the tableting method and the samples containing 20% of 50 mg samples were prepared with polyethylene as the diluent. The thickness of the samples was 1 mm and the diameter was 13 mm. The terahertz time-domain spectrometer was used to obtain the spectral information of aging starch at different aging times. After the pretreatment of the spectrum by vector normalization, first derivative, and multiple scattering correction, the prediction models of aging days, crystallinity, and resilience of aging starch were established, respectively. The determination coefficient (R 2) of the established models is all greater than 95%, indicating that the established models are highly reliable and can be used to predict the aging days, crystallinity, and retrogradation degree of starch. And the R 2 of the prediction model based on the refractive index spectrum is greater than that of the absorption coefficient spectrum. The experimental method obtains the dynamic fingerprint identification map of starch in the aging process, realizes the real-time monitoring and detection of the starch aging process, and provides an effective means for the production and processing of starch-related industries.

13.
J Ethnopharmacol ; 269: 113742, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33359186

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Viburnum taitoense Hayata has been used as folk medicine by the minority people in Southwestern China for a long history, especially in Guangxi Zhuang Autonomous Region. The minority in Guangxi including Zhuang, Miao and Yao people use the ethanol extract of V. taitoense Hayata to treat the fracture, kill the pain of rheumatism because of its definite therapeutic effects. AIM OF THE STUDY: So far, the scientific investigation of V. taitoense Hayata is done very little. Here, we first prepared the ethyl acetate extract of V. taitoense (EEVt), secondly measured the contents of phenols, flavonoids, and terpenoids in EEVt, and thirdly, the anti-inflammatory and analgesic activities of EEVt were investigated by invitro model of RAW 264.7 cells and invivo models of inflammation and pain in rats and mice. MATERIALS AND METHODS: The contents of phenols, flavonoids, and terpenoids in EEVt were determined by UV spectrophotometry, respectively. The anti-inflammatory effect of EEVt (5, 25, 50, 100, and 200 µg/mL) in vitro was tested by determining its inhibitory effect on the nitric oxide production of RAW264.7 cells activated by lipopolysaccharide (LPS). The anti-inflammatory and analgesic effects of EEVt in vivo were investigated in the following experimental rats and mice models: carrageenan-induced paw edema, corton-oil-induced ear edema, acetic acid writhing test, and formalin pain test. RESULTS: The contents of total phenolic, total flavonoids, and total triterpenoids in V. taitoense were measured to be 3.46 ± 0.04%, 2.38 ± 0.04%, and 14.96 ± 0.17%, respectively. In vitro test showed that EEVt at different tested dosages (5, 25, 50, 100, and 200 µg/mL) had no significant toxicity to RAW264.7 macrophages. At dosages of 37.5 and 75 µg/mL of EEVt significant inhibitory (p < 0.001) on the productions of nitric oxide (NO). High dosage (200 µg/mL) of EEVt displayed highly significant inhibitory (p < 0.001) on the productions of proinflammatory cytokines IL-6, IL-1ß, and TNF-α from the LPS-induced RAW264.7 macrophages. EEVt showed obvious anti-inflammatory activity at different time points after carrageenan injection (p < 0.05) in vivo test, and its anti-inflammatory activity reached the strongest 4 h. Similarly, through the ear swelling test, EEVt (200 mg/kg) showed significant (p < 0.05) anti-inflammatory activity. Besides, formalin and acetic acid writhing experiments also showed that EEVt has significant (p < 0.05) analgesic activity. CONCLUSION: EEVt was confirmed to be definite anti-inflammatory and analgesic effects, and the phytochemicals of EEVt was disclosed to be rich in triterpenoids, which was worthy to be further investigated.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Dor/tratamento farmacológico , Extratos Vegetais/farmacologia , Viburnum/química , Acetatos/química , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Carragenina/toxicidade , China , Citocinas/antagonistas & inibidores , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/tratamento farmacológico , Flavonoides/análise , Flavonoides/química , Formaldeído/toxicidade , Inflamação/induzido quimicamente , Lipopolissacarídeos/toxicidade , Medicina Tradicional/métodos , Camundongos , Óxido Nítrico/antagonistas & inibidores , Dor/induzido quimicamente , Fenóis/análise , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Células RAW 264.7 , Ratos Sprague-Dawley , Terpenos/análise , Terpenos/química
14.
Phytochemistry ; 177: 112453, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32773084

RESUMO

Five previously undescribed lanostane-type triterpenoids, including two triterpenoids with a rearranged side chain (applanoic acids E and F), one C21 nortriterpenoid (16,17-dehydroapplanone E), as well as two highly oxygenated lanostane triterpenoids (methyl applaniate B and applanoic acid G), were isolated from the fruiting bodies of Ganoderma applanatum (Pers.) Pat. Their structures were elucidated on the basis of spectroscopic analysis, X-ray crystallography and ECD data. Applanoic acid E, 16,17-dehydroapplanone E, and methyl applaniate B showed inhibitory effects on the release of NO by LPS-induced BV-2 cells.


Assuntos
Ganoderma , Triterpenos , Carpóforos , Lipopolissacarídeos , Estrutura Molecular
15.
Sci Total Environ ; 749: 141212, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32827819

RESUMO

Despite a ban on the production and use of organochlorine pesticides (OCPs) after 1983, serious OCP pollution still exists in the soil in certain areas of China because OCPs degrade very slowly. Based on a systematic review, we identified 136 relevant papers focusing on soil contamination from hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in China (published from 2001 to 2019). We compiled scientific data, extracted and analyzed relevant information, and summarized the pollution characteristics of HCH and DDT in Chinese soils found in two land use types: agricultural land and land for construction. Related studies on HCH and DDT in Chinese soils focus on the Beijing-Tianjin-Hebei region and the Yangtze and Pearl River Deltas, where agricultural soils are predominant. The average concentrations of both HCH and DDT in agricultural soils were generally lower than the risk screening value (100 µg/kg) in most provinces in China, except for DDT concentrations in the Inner Mongolia autonomous region. However, in certain central and eastern regions, mean or maximum recorded DDT concentrations approaching or exceeding 100 µg/kg were recorded. Regarding land for construction, soils with excessive concentrations of HCH and DDT were primarily observed at sites of operational or defunct pesticide factories. According to isomer and metabolite compositions, HCH and DDT at most sites originated from historical residues, but others may have been new inputs after 1983. Since 2015, the concentrations of HCH and DDT in agricultural soils in China have been decreasing, and those in the soils of land for construction (except for sites of operational or defunct pesticide factories) have not exceeded the standard after 2005. This indicates that the measures to prohibit the production and use of OCPs in China have been effective. However, the management of operational or defunct pesticide factories polluted by OCPs requires further improvement.

16.
Environ Res ; 185: 109457, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32247910

RESUMO

Chlorinated solvents (CS)-contaminated groundwater poses serious risks to the environment and public health. Microorganisms play a vital role in efficient remediation of CS. In this study, the microbial community (bacterial and archaeal) composition of three CS-contaminated groundwater wells located at an abandoned chemical factory which covers three orders of magnitude in concentration (0.02-16.15 mg/L) were investigated via 16S rRNA gene high-throughput sequencing. The results indicated that Proteobacteria and Thaumarchaeota were the most abundant bacterial and archaeal groups at the phylum level in groundwater, respectively. The major bacterial genera (Flavobacterium sp., Mycobacterium sp. and unclassified Parcubacteria taxa, etc.) and archaeal genera (Thaumarchaeota Group C3, Miscellaneous Crenarchaeotic Group and Miscellaneous Euryarchaeotic Group, etc.) might be involved in the dechlorination processes. In addition, Pearson's correlation analyses showed that alpha diversity of the bacterial community was not significantly correlated with CS concentration, while alpha diversity of archaeal community greatly decreased with the increased contamination of CS. Moreover, partial Mantel test indicated that oxidation-reduction potential, dissolved oxygen, temperature and methane concentration were major drivers of bacterial and archaeal community composition, whereas CS concentration had no significant impact, indicating that both indigenous bacterial and archaeal community compositions are capable of withstanding elevated CS contamination. This study improves our understanding of how the natural microbial community responds to high CS-contaminated groundwater.


Assuntos
Archaea , Água Subterrânea , Archaea/genética , Bactérias/genética , RNA Ribossômico 16S/genética , Solventes
17.
Food Chem ; 313: 125930, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31923863

RESUMO

A method based on gas chromatography coupled with triple quadrupole mass spectrometry (GC-MS/MS) combined with QuEChERS extraction was developed to detect furfurals, including furfural, 2-acetylfuran, 5-methyl-2-furfural, and 5-hydroxymethyl-2-furfural, in milk-based dairy products. Under the optimized conditions, good linearity was obtained with correlation coefficients (R2) above 0.999, and the recovery values from the spiked samples were 79.0%-115.0% with relative standard deviations (RSDs) less than 13.1%. The limits of detection (LODS) were in the range of 0.002-0.02 mg/kg. To investigate the effects of the production process on milk-based dairy products, 55 real samples were analysed. The higher contents of furfurals were observed when higher temperatures were used during heat treatment and fermentation. In addition, the Toxtree and T.E.S.T. software programs were used to predict the risks associated with these four furfurals. Ultimately, safe dairy intake levels were determined.


Assuntos
Laticínios/análise , Furaldeído/análise , Leite/química , Animais , Furaldeído/análogos & derivados , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Temperatura
18.
Environ Sci Pollut Res Int ; 25(33): 33216-33224, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30255269

RESUMO

This study aims to determine the current remediation status of contaminated sites in China to support future decision-making for the cleanup of contaminated sites. A survey was conducted in which a questionnaire was administered to 76 remediation practitioners working across China. The major driving force behind remediation was the redevelopment of contaminated brownfield land for residential purposes, mostly funded by profit-driven developers, particularly in Beijing. A large proportion of brownfield sites have been contaminated with organic compounds, reflecting past land use by chemical plants. Risk assessments of contaminated sites are typically based on the guidelines from China's Ministry of Ecology and Environment, the United States Environmental Protection Agency, and local governments. The most frequently used criteria to assess site contamination in China are environmental quality standards, screening values, or both. The majority of remediation efforts use low-technology approaches to treat contaminated soil (e.g., cement kiln, in situ and ex situ solidification/stabilization, landfill, and mechanical soil aeration), while sophisticated, high-technology approaches (e.g., in situ and ex situ thermal desorption, in situ chemical treatment, and bioventing) are less often used. The implementation of the latter, while limited, illustrates that the necessary technology exists to support optimal land remediation in China. In addition to high-technology remediation methods, 6W/1H ideology can be employed when assessing contaminated site for remediation. Graphical abstract ᅟ.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Solo/química , Instalações de Eliminação de Resíduos , China , Tomada de Decisões , Indústrias , Medição de Risco , Inquéritos e Questionários
19.
Sci Rep ; 8(1): 13368, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30190569

RESUMO

Waterborne pathogens have attracted a great deal of attention in the public health sector over the last several decades. However, little is known about the pathogenic microorganisms in urban water systems. In this study, the bacterial community structure of 16 typical surface waters in the city of Beijing were analyzed using Illumina MiSeq high-throughput sequencing based on 16S rRNA gene. The results showed that Bacteroidetes, Proteobacteria and Actinobacteria were the dominant groups in 16 surface water samples, and Betaproteobacteria, Alphaproteobacteria, Flavobacteriia, Sphingobacteriia and Actinobacteria were the most dominant classes. The dominant genus across all samples was Flavobacterium. In addition, fifteen genus level groups of potentialy pathogenic bacteria were detected within the 16 water samples, with Pseudomonas and Aeromonas the most frequently identified. Spearman correlation analysis demonstrated that richness estimators (OTUs and Chao1) were correlated with water temperature, nitrate and total nitrogen (p < 0.05), while ammonia-nitrogen and total nitrogen were significantly correlated with the percent of total potential pathogens (p ≤ 0.05). These results could provide insight into the ecological function and health risks of surface water bacterial communities during the process of urbanization.


Assuntos
Bactérias , Consórcios Microbianos , Microbiologia da Água , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Humanos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Reforma Urbana
20.
ACS Appl Mater Interfaces ; 9(10): 8490-8497, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28218519

RESUMO

The binding events between damaged DNA and recognition biomolecules are of great interest for understanding the activity of DNA-damaging drugs and the related DNA repair networks. Herein, a simple and sensitive sensor system was tailored for real-time probing of the dynamic molecular recognition between cisplatin-damaged-DNA (cisPt-DNA) and a cellular responsive protein, high-mobility-group box 1 (HMGB1). By integration of flow injection analysis (FIA) with quartz crystal microbalance (QCM), the interaction time-course of cisPt-DNA and HMGB1 domain A (HMGB1a) was investigated. The highly specific sensing interface was carefully designed and fabricated using cisPt-DNA as recognition element. A hybrid self-assembled monolayer consisting of cysteamine and mercaptohexanol was introduced to resist nonspecific adsorption. The calculated kinetic parameters (kass and kdiss) and the dissociation constant (KD) demonstrated the rapid recognition and tight binding of HMGB1a toward cisPt-DNA. Molecular docking was employed to simulate the complex formed by cisPt-DNA and HMGB1a. The tight binding of such a DNA-damage responsive complex is appealing for the downstream molecular recognition event related to the resistance to DNA repair. This continuous-flow QCM biosensor is an ideal tool for studying specific interactions between drug-damaged-DNAs and their recognition proteins in a physiological-relevant environment, and will provide a potential sensor platform for rapid screening and evaluating metal anticancer drugs.


Assuntos
Técnicas Biossensoriais , DNA , Simulação de Acoplamento Molecular , Proteínas , Quartzo , Técnicas de Microbalança de Cristal de Quartzo
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