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1.
Fitoterapia ; 175: 105974, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663563

RESUMO

Alhagi honey is derived from the secretory granules of Alhagi pseudoalhagi Desv., a leguminous plant commonly known as camelthorn. Modern medical research has demonstrated that the extract of Alhagi honey possesses regulatory properties for the gastrointestinal tract and immune system, as well as exerts anti-tumor, anti-oxidative, anti-inflammatory, anti-bacterial, and hepatoprotective effects. The aim of this study was to isolate and purify oligosaccharide monomers (referred to as Mel) from camelthorn and elucidate their structural characteristics. Subsequently, the impact of Mel on liver injury induced by carbon tetrachloride (CCl4) in mice was investigated. The analysis identified the isolated oligosaccharide monomer (α-D-Glcp-(1 â†’ 3)-ß-D-Fruf-(2 â†’ 1)-α-D-Glcp), with the molecular formula C18H32O16. In a mouse model of CCl4-induced liver fibrosis, Mel demonstrated significant therapeutic effects by attenuating the development of fibrosis. Moreover, it enhanced anti-oxidant enzyme activity (glutathione peroxidase and superoxide dismutase) in liver tissues, thereby reducing oxidative stress markers (malondialdehyde and reactive oxygen species). Mel also improved serum albumin levels, lowered liver enzyme activities (aspartate aminotransferase and alanine aminotransferase), and decreased inflammatory factors (tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-6). Immunohistochemistry, immunofluorescence, and western blotting analyses confirmed the ability of Mel to downregulate hepatic stellate cell-specific markers (collagen type I alpha 1 chain, alpha-smooth muscle actin, transforming growth factor-beta 1. Non-targeted metabolomics analysis revealed the influence of Mel on metabolic pathways related to glutathione, niacin, pyrimidine, butyric acid, and amino acids. In conclusion, the results of our study highlight the promising potential of Mel, derived from Alhagi honey, as a viable candidate drug for treating liver fibrosis. This discovery offers a potentially advantageous option for individuals seeking natural and effective means to promote liver health.

2.
Int J Biol Macromol ; 264(Pt 1): 130351, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403231

RESUMO

The DNA damage response (DDR) safeguards the stable genetic information inheritance by orchestrating a complex protein network in response to DNA damage. However, this mechanism can often hamper the effectiveness of radiotherapy and DNA-damaging chemotherapy in destroying tumor cells, causing cancer resistance. Inhibiting DDR can significantly improve tumor cell sensitivity to radiotherapy and DNA-damaging chemotherapy. Thus, DDR can be a potential target for cancer treatment. Post-translational modifications (PTMs) of DDR-associated proteins profoundly affect their activity and function by covalently attaching new functional groups. O-GlcNAcylation (O-linked-N-acetylglucosaminylation) is an emerging PTM associated with adding and removing O-linked N-acetylglucosamine to serine and threonine residues of proteins. It acts as a dual sensor for nutrients and stress in the cell and is sensitive to DNA damage. However, the explanation behind the specific role of O-GlcNAcylation in the DDR remains remains to be elucidated. To illustrate the complex relationship between O-GlcNAcylation and DDR, this review systematically describes the role of O-GlcNAcylation in DNA repair, cell cycle, and chromatin. We also discuss the defects of current strategies for targeting O-GlcNAcylation-regulated DDR in cancer therapy and suggest potential directions to address them.


Assuntos
Neoplasias , Processamento de Proteína Pós-Traducional , Dano ao DNA , Reparo do DNA , DNA/metabolismo , Acetilglucosamina/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética
3.
Sci Total Environ ; 914: 169890, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38190909

RESUMO

Excitation-emission matrix (EEM) fluorescence spectroscopy is a widely-used method for characterizing the chemical components of brown carbon (BrC). However, the molecular basics and formation mechanisms of chromophores, which are decomposed by parallel factor (PARAFAC) analysis, are not yet fully understood. In this study, we characterized the water-soluble organic carbon (WSOC) in aerosols collected from Karachi, Pakistan, using EEM spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). We identified three PARAFAC components, including two humic-like components (C1 and C2) and one phenolic-like species (C3). We determined the molecular families associated with each component by performing Spearman correlation analysis between FT-ICR MS peaks and PARAFAC component intensities. We found that the C1 and C2 components were associated with nitrogen-enriched compounds, where C2 with the longest emission wavelength exhibited a higher level of aromaticity, N content, and oxygenation than C1. The C3 associated formulas have fewer nitrogen-containing species, a lower unsaturation degree, and a lower oxidation state. An oxidation pathway was identified as an important process in the formation of C1 and C2 components at the molecular level, particularly for the assigned CHON compounds associated with the gas-phase oxidation process, despite their diverse precursor types. Numerous C2 formulas were found in the "potential BrC" region and overlapped with the BrC-associated formulas. It can be inferred that the compounds that fluoresce C2 contributed considerably to the light absorption of BrC. These findings are essential for future studies utilizing the EEM-PARAFAC method to explore the sources, processes, and compositions of atmospheric BrC.

4.
J Ethnopharmacol ; 321: 117552, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38072293

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: According to the theory of traditional Chinese medicine, the main factors related to alcoholic liver disease (ALD) are qi stagnation and blood stasis of the five viscera. Previously, we showed that the bioactive components of Alhagi honey have various pharmacological effects in treating liver diseases, but the influence of Alhagi honey on ALD (and its mechanism of action) is not known. AIM OF THE STUDY: To determine the efficacy of the main active component of Alhagi honey, the polysaccharide AHPN80, in ALD and to explore the potential mechanism of action. MATERIALS AND METHODS: AHPN80 was isolated from dried Alhagi honey and identified by transmission electron microscopy, Fourier-transform infrared spectroscopy, and gas chromatography. Venous blood, liver tissue, and colon tissue were collected in a mouse model of alcohol-induced acute liver injury. Histology, staining (Oil Red O, Alcian Blue-Periodic Acid Schiff) and measurement of reactive oxygen species (ROS) levels were used to detect histopathologic and lipid-accumulation changes in the liver and colon. Lipopolysaccharide (LPS) levels and the content of proinflammatory cytokines in serum were measured by enzyme-linked immunosorbent assays. Commercial kits were employed to detect biochemistry parameters in serum and the liver. A terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining kit was used to identify hepatocyte apoptosis. Expression of tight junction-associated proteins in colon tissues and nuclear factor erythroid 2-related factor 2/heme oxygenase-1/toll-like receptor-4/mitogen-activated protein kinase (Nrf2/HO-1/TLR4/MAPK) pathway-related proteins in liver tissues and HepG2 cells were analyzed by immunofluorescence or western blotting. RESULTS: In a mouse model of alcohol-induced acute liver injury, AHPN80 therapy: significantly improved liver parameters (cytochrome P450 2E1, alcohol dehydrogenase, aldehyde dehydrogenase, superoxide dismutase, malondialdehyde, glutathione peroxidase, catalase, total cholesterol, triglycerides, alanine transaminase, aspartate transaminase); reduced serum levels of LPS, interleukin (IL)-1ß, IL-6, and tumor necrosis faction-α; increased levels of IL-10 and interferon-gamma. AHPN80 reduced ALD-induced lipid accumulation and ROS production, improved alcohol-induced inflammatory damage to hepatocytes, and inhibited hepatocyte apoptosis. Immunofluorescence staining and western blotting suggested that AHPN80 might eliminate hepatic oxidative stress by activating the Nrf2/HO-1 signaling pathway, repair the intestinal barrier, inhibit the LPS/TLR4/MAPK signaling pathway, and reduce liver inflammation. CONCLUSIONS: AHPN80 may activate the Nrf2/HO-1 pathway to eliminate oxidative stress, protect the intestinal barrier, and regulate the TLR4/MAPK pathway to treat ALD in mice. AHPN80 could be a functional food and natural medicine to prevent ALD and its complications.


Assuntos
Mel , Hepatopatias Alcoólicas , Camundongos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipopolissacarídeos/farmacologia , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , Fígado , Hepatopatias Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/prevenção & controle , Estresse Oxidativo , Etanol/farmacologia , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico
5.
Sci Total Environ ; 912: 169290, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38104832

RESUMO

Biomass burning (BB) releases large amounts of water-soluble organic carbon (WSOC), which would undergo heterogenous oxidation processes that induce transformations in both molecular structures and compositions within BB WSOC. This study designed an aqueous oxidation initiated by OH radicals in the absence of light for WSOC extracted from smoke particles generated by burning of corn straw and fir wood. The BB WSOC was comprehensively characterized using a combination of UV-visible spectra, excitation-emission matrix fluorescence in conjunction with parallel factor analysis (EEM-PARAFAC), high-performance size exclusion chromatography (HPSEC), and high-resolution mass spectrometry (HRMS) analyses. Over the course of oxidation, both chromophores and fluorophores exhibited gradual decreases. Moreover, EEM-PARAFAC revealed a preferential degradation of larger-sized protein-like/phenol-like organic matters, accompanied by the accumulation and/or formation of humic-like substances in aged BB WSOC. HPSEC analysis showed notable changes in molecular weight (MW) distributions for both types of BB WSOC during oxidation. Specifically, high MW species (>1 kDa) displayed a tendency to form along with oxidation, possibly attributed to the formation of assemblies via intermolecular weak forces. After oxidation, evidence of CHO compound degradation and enrichment/formation of CHON compounds was observed for both types of BB WSOC. Remarkably, the resistant, degraded and produced molecules for BB WSOC were dominated by CHO (38-73 %) and lignin-like molecules (41-47 %), suggesting diverse responses to oxidation within these two groups. Furthermore, polyphenols experienced selective degradation, while CHON, aliphatic and poly-aromatic molecules tended to form during the oxidation process for both types of BB WSOC. In summary, this study provides a comprehensive understanding of the molecular-level transformations undergone by BB WSOC during dark aqueous OH oxidation. The findings significantly contribute to our insights into atmospheric evolution of BB WSOC, thereby playing a crucial role in accurately assessing their effects within climate models and informing policy decisions.

6.
Int J Biol Macromol ; 259(Pt 1): 128937, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38145695

RESUMO

The Alhagi honey polysaccharide (AHP) exhibits notable anti-inflammatory, antioxidant, and immunomodulatory properties, positioning it as a promising candidate in traditional Chinese medicine. In this investigation, we successfully isolated and purified a neutral AHP, designated AHPN50-1a, subsequently elucidating its structural attributes. AHPN50-1a was found to have a molecular weight of 1.756 × 106 Da, featuring a structural motif characterized by a recurring (1→6)-α-GlcP linker. To comprehensively evaluate its therapeutic potential, we explored the protective effects of AHPN50-1 in a murine model of dextran sodium sulfate-induced colitis. Administration of AHPN50-1 at doses of 200 and 400 mg/kg/day resulted in improved food intake, increased body weight, and increased colon length in mice with acute colitis. Simultaneously, a reduction in the disease activity index and histological scores was observed. AHPN50-1 effectively mitigated colon tissue damage, down-regulated the expression levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) in colon tissue, restored intestinal microbiota diversity, and concentrations of short-chain fatty acids (SCFAs) of gut microbiota metabolites, thus alleviating intestinal inflammation in mice. In summary, our findings underscore the promise of AHPN50-1 as a valuable nutritional or dietary supplement for the treatment and prevention of inflammatory bowel disease.


Assuntos
Colite , Microbioma Gastrointestinal , Mel , Doenças Inflamatórias Intestinais , Animais , Camundongos , Colo , Disbiose/tratamento farmacológico , Disbiose/patologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Citocinas/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/química , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
7.
Nat Commun ; 14(1): 6444, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833278

RESUMO

Emission factors and inventories of black carbon (BC) aerosols are crucial for estimating their adverse atmospheric effect. However, it is imperative to separate BC emissions into char and soot subgroups due to their significantly different physicochemical properties and potential effects. Here, we present a substantial dataset of char and soot emission factors derived from field and laboratory measurements. Based on the latest results of the char-to-soot ratio, we further reconstructed the emission inventories of char and soot for the years 1960-2017 in China. Our findings indicate that char dominates annual BC emissions and its huge historical reduction, which can be attributable to the rapid changes in energy structure, combustion technology and emission standards in recent decades. Our results suggest that further BC emission reductions in both China and the world should focus on char, which mainly derives from lower-temperature combustion and is easier to decrease compared to soot.

8.
Heliyon ; 9(10): e20386, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37767496

RESUMO

By targeting the membrane (M) proteins of monkeypox virus (MPXV) strain VEROE6, we analyzed its evolutionary hierarchy and predicted its dominant antigenic B-cell epitope to provide a theoretical basis for the development of MPXV epitope vaccines and related monoclonal antibodies. In this study, phylogenetic trees were constructed based on the nucleic acid sequences of MPXV and the amino acid sequences of M proteins. The 3D structure of the MPXV_VEROE6 M proteins was predicted with AlphaFold v2.0 and the dominant antigenic B-cell epitopes were comprehensively predicted by analyzing parameters such as flexible segments, the hydrophilic index, the antigenic index, and the protein surface probability. The results showed that the M protein of MPXV_VEROE6 contained 377 amino acids, and their spatial configuration was relatively regular with a turning and random coil structure. The results of a comprehensive multiparameter analysis indicated that possible B-cell epitopes were located in the 23-28, 57-63, 67-78, 80-93, 98-105, 125-131, 143-149, 201-206, 231-237, 261-270, 291-303, and 346-362 amino acid segments. This study elucidated the structural and evolutionary characteristics of MPXV membrane proteins with the aim of providing theoretical information for the development of epitope vaccines, rapid diagnostic reagents, and monoclonal antibodies for monkeypox virus.

9.
Chemosphere ; 338: 139517, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454992

RESUMO

Atmospheric brown carbon (BrC) contain amounts of organic species, but their molecular weight (MW) distributions is still poorly understood. This study applied high-performance size exclusion chromatography (HPSEC) coupled with a diode array detector (DAD) and fluorescence detector (FLD) to characterize the MW distributions of typical chromophores and fluorophores within water-soluble BrC. The investigation focused on the spring season, encompassing both typical urban and rural aerosols. Our results showed that chromophores (at 254 and 365 nm), and humic-like and protein-like fluorophores identified by excitation-emission matrix parallel factor analysis (EEM-PARAFAC) within BrC were broadly distributed along the MW continuum (∼50-20,000 Da). This suggests that BrC mainly comprises complex chromophores and fluorophores with heterogeneous molecular sizes. High-MW (HMW, >1 kDa) species (66%-74%) dominated the chromophores at 254 and 365 nm. However, the latter chromophores were enriched with more HMW species. This result suggested that the HMW chromophores might contribute more to BrC absorption at longer wavelengths. The PARAFAC-derived fluorescent components also exhibited different MW distributions. Three humic-like substances (HULIS) were all dominated by HMW fractions (51%-74%), but protein-like fluorescent component (PLOM) enriched low-MW (LMW, <1 kDa) species (60%-66%). Furthermore, the molecular size (i.e., weight-averaged and number-averaged MW) and the ratios between HMW and LMW species decreased in the order highly-oxygenated HULIS > less-oxygenated HULIS > PLOM, indicating that the fluorophores with longer Em were generally related to larger MW. To our knowledge, this is the first report on the molecular size of individual fluorescent components within aerosol BrC. The results obtained here enhanced our knowledge of heterogeneous composition, complex physicochemical properties, and potential atmospheric fates of aerosol BrC.


Assuntos
Carbono , Água , Carbono/análise , Peso Molecular , Água/química , Cromatografia em Gel , Substâncias Húmicas/análise , Corantes Fluorescentes/análise , Aerossóis/análise , Monitoramento Ambiental
10.
Environ Sci Technol ; 56(1): 119-130, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34882389

RESUMO

N-containing organic compounds (NOCs) in humic-like substances (HULIS) emitted from biomass burning (BB) and coal combustion (CC) were characterized by ultrahigh-resolution mass spectrometry in the positive electrospray ionization mode. Our results indicate that NOCs include CHON+ and CHN+ groups, which are detected as a substantial fraction in both BB- and CC-derived HULIS, and suggest that not only BB but also CC is the potential important source of NOCs in the atmosphere. The CHON+ compounds mainly consist of reduced nitrogen compounds with other oxygenated functional groups, and straw- and coal-smoke HULIS exhibit a lower degree of oxidation than pine-smoke HULIS. In addition, the NOCs with higher N atoms (N2 and/or N3) generally bear higher modified aromaticity index (AImod) values and are mainly contained in BB HULIS, especially in straw-smoke HULIS, whereas the NOCs with a lower N atom (N1) always have relatively lower AImod values and are the dominant NOCs in CC HULIS. These findings imply that the primary emission from CC may be a significant source of N1 compounds, whereas high N number (e.g., N2-3) compounds could be associated with burning of biomass materials. Further study is warranted to distinguish the NOCs from more sources.


Assuntos
Poluentes Atmosféricos , Carvão Mineral , Aerossóis/análise , Poluentes Atmosféricos/análise , Biomassa , Monitoramento Ambiental , Substâncias Húmicas/análise , Nitrogênio/análise , Compostos de Nitrogênio/análise , Material Particulado/análise
11.
Chemosphere ; 278: 130439, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33836401

RESUMO

The metal-binding characteristics of water-soluble organic matter (WSOM) emitted from biomass burning (BB, i.e., rice straw (RS) and corn straw (CS)) with Cu(II) under various pH conditions (i.e., 3, 4.5, and 6) were comprehensively investigated. Two-dimensional correlation spectroscopy (2D-COS) and excitation-emission matrix (EEM) -PARAFAC analysis were applied to investigate the binding affinity and mechanism of BB WSOM. The results showed that pH was a sensitive factor affecting binding affinities of WSOM, and BB WSOMs were more susceptible to bind with Cu(II) at pH 6.0 than pH 4.5, followed by pH 3.0. Therefore, the Cu(II)-binding behaviors of BB WSOMs at pH 6.0 were then investigated in this study. The 2D-absorption-COS revealed that the preferential binding with Cu(II) was in the order short and long wavelengths (237-239 nm and 307-309 nm) > moderate wavelength (267-269 nm). The 2D-synchronous fluorescence-COS results suggested that protein-like substances generally exhibited a higher susceptibility and preferential interaction with Cu(II) than fulvic-like substances. EEM-PARAFAC analysis demonstrated that protein-like (C1) substances had a greater complexation ability than fulvic-like (C2) and humic-like (C3) substances for both BB WSOM. This indicated that protein-like substances within WSOM played dominant roles in the interaction with Cu(II). As a comparison, RS WSOM generally showed stronger complexation capacity than CS WSOM although they exhibited similar chemical properties and compositions. This suggested the occurrence of heterogeneous active metal-binding sites even within similar chromophores for different WSOM. The results enhanced our understanding of binding behaviors of BB WSOM with Cu(II) in relevant atmospheric environments.


Assuntos
Cobre , Substâncias Húmicas , Biomassa , Análise Fatorial , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência , Água
12.
Environ Pollut ; 268(Pt A): 115906, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33120333

RESUMO

Fluorescence spectroscopy is a commonly used technique to analyze dissolved organic matter in aquatic environments. Given the high sensitivity and non-destructive analysis, fluorescence has recently been used to study water-soluble organic carbon (WSOC) in atmospheric aerosols, which have substantial abundance, various sources and play an important role in climate change. Yet, current research on WSOC characterization is rather sparse and limited to a few isolated sites, making it challenging to draw fundamental and mechanistic conclusions. Here we presented a review of the fluorescence properties of atmospheric WSOC reported in various field and laboratory studies, to discuss the current advances and limitations of fluorescence applications. We highlighted that photochemical reactions and relevant aging processes have profound impacts on fluorescence properties of atmospheric WSOC, which were previously unnoticed for organic matter in aquatic environments. Furthermore, we discussed the differences in sources and chemical compositions of fluorescent components between the atmosphere and hydrosphere. We concluded that the commonly used fluorescence characteristics derived from aquatic environments may not be applicable as references for atmospheric WSOC. We emphasized that there is a need for more systematic studies on the fluorescence properties of atmospheric WSOC and to establish a more robust reference and dataset for fluorescence studies in atmosphere based on extensive source-specific experiments.


Assuntos
Poluentes Atmosféricos , Carbono , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Fluorescência , Material Particulado/análise , Água
13.
Environ Pollut ; 267: 115492, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33254672

RESUMO

Dichlorodiphenyltrichloroethane (DDT) is well known for its harmful effects and has been banned around the world. However, DDT is still frequently detected in natural environments, particularly in aquaculture and harbor sediments. In this study, 15 surface sediment samples were collected from a typical tropical bay (Zhanjiang Bay) in the South China Sea, and the levels of DDT and its metabolites in sediment and porewater samples were investigated. The results showed that concentrations of DDXs (i.e., DDT and its metabolites) in bulk sediments were 1.58-51.0 ng g-1 (mean, 11.5 ng g-1). DDTs (DDT and its primary metabolites, dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE)) were the most prominent, accounting for 73.2%-98.3% (86.1% ± 12.8%) of the DDXs. Additionally, high-order metabolites (i.e., 1-chloro-2,2-bis(4'-chlorophenyl)ethylene (p,p'-DDMU), 2,2-bis(p-chlorophenyl)ethylene (p,p'-DDNU), 2,2-bis(p-chlorophenyl)ethanol (p,p'-DDOH), 2,2-bis(p-chlorophenyl)methane (p,p'-DDM), and 4,4'-dichlorobenzophenone (p,p'-DBP)) were also detected in most of the sediment and porewater samples, with DDMU and DBP being predominant. The DDTs concentration differed among the sampling sites, with relatively high DDTs concentrations in the samples from the aquaculture zone and an area near the shipping channel and the Haibin shipyard. The DDD/DDE ratios indicated a reductive dichlorination of DDT to DDD under anaerobic conditions at most of the sampling sites of Zhanjiang Bay. The possible DDT degradation pathway in the surface sediments of Zhanjiang Bay was p,p'-DDT/p,p'-DDD(p,p'-DDE)/p,p'-DDMU/p,p'-DDNU/ … /p,p'-DBP. The DDXs in the sediments of Zhanjiang Bay were mainly introduced via mixed sources of industrial DDT and dicofol, including fresh input and historical residue. The concentrations of DDXs in porewater samples varied from 66.3 to 250 ng L-1, exhibiting a distribution similar to that in the accompanying sediments. However, the content of high-order metabolites was relatively lower in porewater than in sediment, indicating that high-order degradation mainly occurs in particles. Overall, this study helps in understanding the distribution, source, and degradation of DDT in a typical tropical bay.


Assuntos
DDT , Poluentes Químicos da Água , Baías , China , DDT/análise , Monitoramento Ambiental , Sedimentos Geológicos , Poluentes Químicos da Água/análise
14.
Environ Pollut ; 262: 114266, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32155548

RESUMO

Humic-like substances (HULIS) are complex mixtures that are highly associated with brown carbon (BrC) and are important components of biomass burning (BB) emissions. In this study, we investigated the light absorption, emission factors (EFs), and amounts of HULIS emitted from the simulated burning of 27 types of regionally important rainforest biomass in Southeast Asia. We observed that HULIS had a high mass absorption efficiency at 365 nm (MAE365), with an average value of 2.6 ± 0.83 m2 g-1 C. HULIS emitted from BB accounted for 65% ± 13% of the amount of water-soluble organic carbon (WSOC) and 85% ± 10% of the light absorption of WSOC at 365 nm. The EFs of HULIS from BB averaged 2.3 ± 2.1 g kg-1 fuel, and the burning of the four vegetation subtypes (herbaceous plants, shrubs, evergreen trees, and deciduous trees) exhibited different characteristics. The differences in EFs among the subtypes were likely due to differences in lignin content in the vegetation, the burning conditions, or other factors. The light absorption characteristics of HULIS were strongly associated with the EFs. The annual emissions (minimum-maximum) of HULIS from BB in this region in 2016 were 200-371 Gg. Furthermore, the emissions from January to April accounted for 99% of the total annual emissions of HULIS, which is likely the result of the burning activities during this season. The most significant emission regions were Cambodia, Burma, Thailand, and Laos. This study, which evaluated emissions of HULIS by simulating open BB, contributes to a better understanding of the light-absorbing properties and regional budgets of BrC in this region.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Aerossóis , Sudeste Asiático , Biomassa , Camboja , Carbono/análise , Monitoramento Ambiental , Floresta Úmida , Tailândia
15.
Sci Total Environ ; 718: 137322, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32092515

RESUMO

It is essential to fully understand the physicochemical properties and sources of atmospheric chromophores to evaluate their impacts on environmental quality and global climate. Three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy is an important method for directly characterizing the occurrences, origins, and chemical behaviors of atmospheric chromophores. However, there is still a lack of adequate information on the sources and chemical structures of EEM-defined chromophores. This situation limits the extensive application of the EEM method in the study of atmospheric chromophores. Under these adverse conditions, this work uses the analysis of EEM data by the parallel factor (PARAFAC) analysis model and a comprehensive comparison of the types and abundances of different chromophores in different aerosol samples (combustion source samples, secondary organic aerosols, and ambient aerosols) to demonstrate that the EEM method can distinguish among different chromophore types and aerosol sources. Indeed, approximately half of all fluorescent substances can be attributed to specific chemicals and sources. These findings provide an important basis for the study of the sources and chemical processes of atmospheric chromophores by the EEM approach.

16.
Environ Pollut ; 256: 113408, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662267

RESUMO

The m-aminophenol (m-AP) is a widely used industrial chemical, which enters water, soils, and sediments with waste emissions. A common soil metal oxide, birnessite (δ-MnO2), was found to mediate the transformation of m-AP with fast rates under acidic conditions. Because of the highly complexity of the m-AP transformation, mechanism-based models were taken to fit the transformation kinetic process of m-AP. The results indicated that the transformation of m-AP with δ-MnO2 could be described by precursor complex formation rate-limiting model. The oxidative transformation of m-AP on the surface of δ-MnO2 was highly dependent on reactant concentrations, pH, temperature, and other co-solutes. The UV-VIS absorbance and mass spectra analysis indicated that the pathway leading to m-AP transformation may be the polymerization through the coupling reaction. The m-AP radicals were likely to be coupled by the covalent bonding between unsubstituted C2, C4 or C6 atoms in the m-AP aromatic rings to form oligomers as revealed by the results of activation energy and mass spectra. Furthermore, the toxicity assessment of the transformation productions indicated that the toxicity of m-AP to the E. coli K-12 could be reduced by MnO2 mediated transformation. The results are helpful for understanding the environmental behavior and potential risk of m-AP in natural environment.


Assuntos
Aminofenóis/química , Óxidos/química , Poluentes Químicos da Água/química , Aminofenóis/toxicidade , Escherichia coli , Cinética , Compostos de Manganês , Oxirredução , Estresse Oxidativo , Água , Poluentes Químicos da Água/toxicidade
17.
Sci Rep ; 9(1): 17757, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780678

RESUMO

Adenylate kinase 2 (AK2), an isoenzyme of the AK family, may have momentous extra-mitochondrial functions, especially in tumourigenesis in addition to the well-known control of energy metabolism. In this study, we provided the first evidence that AK2 is overexpressed in lung adenocarcinoma. The positive expression of AK2 is associated with tumor progression, and poor survival in patients with pulmonary adenocarcinoma. Knockdown of AK2 could suppress proliferation, migration, and invasion as well as induce apoptosis and autophagy in human lung adenocarcinoma cells. Remarkably, silencing AK2 exerted the greater tumor suppression roles when combined with hydroxychloroquine, an effective autophagy inhibitor, in vitro and in xenografts mouse models. Our data have probably provided preclinical proof that systematic inhibition of AK2 and autophagy could be therapeutically effective on lung cancer.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico , Adenilato Quinase/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenilato Quinase/análise , Animais , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico
18.
Environ Sci Technol ; 53(23): 13607-13617, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31682114

RESUMO

Water-soluble organic compounds (WSOC) and methanol-soluble organic compounds (MSOC) in smoke particles emitted from residential coal combustion were characterized by ultrahigh-resolution mass spectrometry. The results showed that the molecular compositions of WSOC and MSOC are different. S-containing compounds (CHOS and CHONS) are found to be the dominant components (65-87%) of the WSOC, whereas CHO and CHON compounds make a great contribution (79-96%) to the MSOC samples. It is worth noting that greater abundance of S-containing compounds was found in smoke produced from coal combustion compared to biomass burning and atmospheric samples. The molecular compositions of WSOC and MSOC also varied significantly depending on the maturity of the coal. The WSOC and MSOC derived from the combustion of low-maturity coal contained a higher proportion of oxidized functional groups but with a lower degree of aromaticity than the compounds derived from the combustion of high-maturity coal. Our findings suggest that organic molecules with a high modified aromaticity index, low O/C ratio, and low polarity showed stronger light absorption. This study also suggests that CHO and CHON compounds significantly contributed to the light absorption of WSOC and MSOC and that the contribution of CHON may be stronger.


Assuntos
Carvão Mineral , Metanol , Ciclotrons , Análise de Fourier , Espectrometria de Massas , Espectrometria de Massas por Ionização por Electrospray , Água
19.
Biomed Pharmacother ; 118: 109382, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545257

RESUMO

Renal cell carcinoma (RCC) is one of the most lethal urological malignancies, yet its pathogenesis remains unclear. Here, we reported a long non-coding RNA (lncRNA), NONHSAT 113026 (NOAT113026), which may play an important role in the pathogenesis of RCC. The expression level of NOAT113026 was estimated by qPCR from 76 pairs of RCC and non-tumor (NT) samples. The correlation between NOAT113026 and clinical data of RCC patients was analyzed. NOAT113026 was overexpressed in 786-O and ACHN cell lines by lentivirus-mediated technology and the oncological behavioral changes of RCC cells were observed along with tumorigenicity in experimental nude mice. Compared to the adjacent tissues, NOAT113026 was noticeably downregulated in RCC. Survival analysis showed that the lower the expression level of NOAT113026 was, the shorter the disease-free survival and overall survival in RCC would be. Overexpression of NOAT113026 can decrease the ability of cell migration, invasion, proliferation, and colony formation by regulating NF-κB/p50 and SLUG through a mechanism that involves lncRNA-mRNA interactions. In conclusion, our data suggest that NOAT113026 could be a carcinostatic RNA in RCC, which may serve as a potential prognostic factor and a promising therapeutic target for malignant RCC.


Assuntos
Carcinogênese/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Subunidade p50 de NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/patologia , Masculino , Camundongos Nus , Invasividade Neoplásica , Prognóstico , RNA Longo não Codificante/genética , Regulação para Cima/genética
20.
Huan Jing Ke Xue ; 40(4): 1734-1741, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087914

RESUMO

Sixteen surface sediment samples were collected from the estuary of the Suixi river to the mouth of Zhanjiang Bay and then analyzed for organochlorine pesticides (OCPs) by GC-MS to investigate their distribution and ecological risk. The results showed that the concentrations of OCPs in the sediments ranged from nd to 189.52 ng·g-1 (mean 32.17 ng·g-1), including HCHs (mean 5.81 ng·g-1) and DDTs (mean 26.90 ng·g-1). The distribution characteristics showed that the highest OCPs concentrations were found in the estuary and the main shipping lane areas, and the concentration in the nearshore area was higher than that offshore. Source analysis indicated that the HCHs mainly originated from agricultural applications, while no industrial input was observed. Some "hot-spots" areas occurred in harbors and shipping channels, likely as a result of the presence of paint flakes. Additionally, the concentrations of DDTs were found to be higher than the limits of Chinese Marine sediment quality criteria, and p,p'-DDT was the main type of DDT, presenting inevitable adverse biological effects and high ecological risk. Compared with other bays in China, the concentrations of OCPs in this study were in the upper-median pollution level, especially in harbors and boat maintenance facility areas. High OCPs inputs may occur, and thereby represent a certain ecological risk in Zhanjiang Bay.

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