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Due to its unique geometric structure, the bidirectional ultrafast fiber laser is an excellent light source for dual-comb applications. However, sharing the same gain between the counter-propagating solitons also gives rise to complex dynamics. Herein, we report the anti-phase pulsation of counter-propagating dissipative solitons in a bidirectional fiber laser. The in-phase and anti-phase soliton pulsation can be manipulated by adjusting the intracavity birefringence. The periodic modulation of polarization-dependent gain (PDG) caused by polarization hole burning (PHB) in the gain fiber can be responsible for anti-phase pulsation of bidirectional dissipative solitons. These findings offer new, to the best of our knowledge, insights into the complex dynamics of solitons in dissipative optical systems and performance improvement of bidirectional ultrafast fiber lasers.
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BACKGROUND: Crocetin is a bioactive ingredient in saffron, derived from the Crocus sativus stigmas of the Iridaceae family. As a chemically carotenoid derivative, crocetin exhibites effects like anti-inflammatory, antioxidant, neuroprotective, etc. However, the protective effect of crocetin on glaucoma and its mechanism remains unclear. The current study assesed the neuroprotective and anti-inflammatory effects of crocetin on retinal neurons in glaucoma rats which were induced by 0.3% carbomer injection into the anterior chamber. METHODS AND RESULTS: The pathological structures on the retina and optic nerve were observed and examined by H&E staining and transmission electron microscopy. Immunohistochemical staining was used to detect the expression of TNF-α, IL-1ß, and IL-6 of the retina and the expression of a brain-derived neurotrophic factor (BDNF) in the primary visual cortex (PVC). Western blot was carried out to detect the expression of PI3K, Akt, and NF-κB in the retina. It was found that crocetin ameliorated the pathological changes of the retina and ON and reduced the number of apoptotic retinal ganglion cells. Immunohistochemical staining showed that crocetin could decrease the contents of TNF-α, IL-1ß, and IL-6 and increase the contents of BDNF. Western blot showed that crocetin was found to suppress the expression of PI3K, Akt, and NF-κB. CONCLUSION: The results obtained in this study have indicated that crocetin showes neuroprotective effects on retinal ganglion cells in glaucoma rats and inhibits retinal dysfunction. Meanwhile, crocetin exerted an anti-inflammatory effect to protect the retina by inhibiting the expression of the PI3K/Akt/NF-κB signaling pathway. This work provides substantial evidence that crocetin may be a potential drug for the treatment of glaucoma.
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Glaucoma , NF-kappa B , Ratos , Animais , NF-kappa B/metabolismo , Fator Neurotrófico Derivado do Encéfalo , Neuroproteção , Fator de Necrose Tumoral alfa , Proteínas Proto-Oncogênicas c-akt , Fosfatidilinositol 3-Quinases , Interleucina-6 , Glaucoma/tratamento farmacológico , Anti-Inflamatórios/farmacologiaRESUMO
The disadvantages of limited working pH range and poor stability have hindered the practical application of traditional electro-Fenton process. In this research, a novel heterogeneous electro-Fenton (HEF) process with FeIIFeIII layered double hydroxide/carbon felt (FeIIFeIII LDH/CF) as cathode was developed for the rapid destruction of ciprofloxacin (CIP) in bulk solution. Effects of crucial influencing factors (initial pH, current intensity) on CIP degradation were investigated. Results indicated that FeIIFeIII LDH/CF cathode was efficient for CIP degradation (88.11%). Furthermore, CIP degradation performance in HEF could remain stable over wide range of pH (pH 3-9). The catalytic degradation of CIP in HEF process might be a combined effect of homogeneous EF reaction, anodic oxidation, and surface catalysis process via≡FeII/≡FeIII cycle. Possible degradation pathways were proposed. The results suggested that FeIIFeIII LDH/CF cathode showed great application potential for CIP degradation.
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Ciprofloxacina , Poluentes Químicos da Água , Carbono , Fibra de Carbono , Eletrodos , Compostos Férricos , Peróxido de Hidrogênio , Hidróxidos , OxirreduçãoRESUMO
Manganese oxides (MnxOy) are critical for determining the environmental behaviors and fate of antimonite (Sb(III)). However, little is known about the qualitative/quantitative connection between MnxOy structures and Sb(III) fate. Herein, the reactions of Sb(III) and six MnxOy with different structures were systematically investigated. The initial oxidation rates of Sb(III) (rinit) on six MnxOy decreased in the order of γ-MnO2>δ-MnO2>α-MnO2>γ-MnOOH>Mn3O4>ß-MnO2 (pHinitial=7.0), from 0.32 ± 0.04 to 11.17 ± 1.61 mmol/min/mol-Mn. The amounts of antimony retained (i.e., the sum of Sb(III) and antimonate (Sb(V))) on these MnxOy followed the same trend as that of oxidation. Oxidation of Sb(III) released Mn(II) and created more sites for adsorption. Outwardly, MnxOy with higher reduction potential (E0) and specific surface area (SSA) favored faster Sb(III) oxidation. Inwardly, Mn(III) and oxygen vacancies (Ov) exhibited a synergistic effect on Sb(III) oxidation. Mn(III) can easier accept electron than Mn(IV) based on the change in Gibbs free energy calculation. Ov can adsorb free oxygen to form surface oxygen (Osur) which is much more reactive than lattice oxygen (Olatt). Moreover, Ov is in close proximity to Mn(III) in high-valent MnxOy which facilitated the reactions between Sb(III) and Mn(III) through the enhancement of Sb(III) adsorption and electron transfer. Ov in low-valent MnxOy is adjacent to Mn(II), thus it showed weaker enhancement than that in high-valent MnxOy. Part of δ-MnO2 and almost all Mn3O4 were converted to γ-MnOOH during their reaction with Sb(III), while the other four MnxOy were barely changed. The results obtained provide mechanistic insight into the reactions occurring within Sb(III) and MnxOy, which are helpful for better understanding and prediction of the fate of Sb(III) in Mn-rich environments.
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Compostos de Manganês , Óxidos , Óxidos/química , Compostos de Manganês/química , Antimônio/química , Manganês , Oxigênio , Oxirredução , AdsorçãoRESUMO
OBJECTIVE: To screen and analyze the function of specific CircRNAs involved in pathological bone formation in patients with ankylosing spondylitis (AS). METHODS: From September 2019 to October 2020, hip capsule tissues obtained from 3 patients with AS developed hip joint fusion and 3 patients with femoral neck fracture (FNF) were obtained. The circular RNA expressions of hip capsule were analyzed by Arraystar CircRNA chip. qRT-PCR analysis wan performed to identify the expression patterns of differentially expression CircRNAs. RESULTS: Our findings showed that there were 25 up-regulated and 39 down-regulated differential CircRNAs. Among these CircRNAs, we screened 10 highest up-regulatedCircRNAs and 13 lowest down-regulated CircRNAs (Fold Change≥2,P<0.05). In further verification analysis, hsa_circ_0067103, hsa_circ_0004496, and hsa_circ_0002649, ACTG1 were significantly upregulated, while hsa_circ_0020273, hsa_circ_0005699, and hsa_circ_0048764 were markly downregulated in AS tissue than FNF controls. CONCLUSION: The expression of CircRNAs involved of pathological bone formation in AS were significantly different from those of control group. These differentially expressed Circular RNAs may be closely related to the occurrence and development of pathological bone formation in AS.
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RNA Circular , Espondilite Anquilosante , Humanos , RNA Circular/genética , Espondilite Anquilosante/genética , Osteogênese/genética , Análise de Sequência com Séries de OligonucleotídeosRESUMO
Diabetes is a global health problem which is accompanied with multi-systemic complications. It is of great significance to elucidate the pathogenesis and to identify novel therapies of diabetes and diabetic complications. Sestrin2, a stress-inducible protein, is primarily involved in cellular responses to various stresses. It plays critical roles in regulating a series of cellular events, such as oxidative stress, mitochondrial function and endoplasmic reticulum stress. Researches investigating the correlations between Sestrin2, diabetes and diabetic complications are increasing in recent years. This review incorporates recent findings, demonstrates the diverse functions and regulating mechanisms of Sestrin2, and discusses the potential roles of Sestrin2 in the pathogenesis of diabetes and diabetic complications, hoping to highlight a promising therapeutic direction.
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Complicações do Diabetes , Diabetes Mellitus , Humanos , Proteínas Nucleares/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Estresse OxidativoRESUMO
PURPOSE: To estimate the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and to evaluate the associations between thyroid parameters, MAFLD and liver fibrosis in euthyroid patients with newly diagnosed type 2 diabetes mellitus (T2DM). METHODS: Overall, 776 patients with newly diagnosed T2DM and 120 subjects without diabetes were included. All the participants were euthyroid, and were categorized as non-MAFLD and MAFLD. Demographic information, biochemical parameters, and serum thyroid hormones were collected. The thyroid hormone sensitivity indices were calculated. MAFLD was defined according to abdominal ultrasound and clinical manifestations. Noninvasive fibrosis indices were calculated to identify advanced liver fibrosis. RESULTS: The prevalence of MAFLD was significantly higher in patients with T2DM than in subjects without diabetes. Levels of free triiodothyronine (FT3) and FT3 to free thyroxine (FT4) ratio were significantly higher in subjects with MAFLD. In patients with T2DM, levels of thyroid stimulating hormone (TSH), Thyroid feedback quantile-based index (TFQIFT3) calculated using FT3 and TSH, thyrotroph T3 resistance index (TT3RI) and thyrotroph T4 resistance index (TT4RI) were significantly higher in subjects with MAFLD. The prevalence of MAFLD increased with the rise of FT3, FT3/FT4, TSH, and sensitivity to thyroid hormone indices (TFQIFT3, TT3RI, and TT4RI). But significant correlations were not found between thyroid hormones, sensitivity to thyroid hormones and MAFLD, after adjustment for BMI and HOMA-IR. The incidence of advanced fibrosis tended to increase as the rise of TSH and sensitivity to thyroid hormone indices (TFQIFT3, TT3RI, TT4RI, and TSHI). CONCLUSION: MAFLD was prevalent in euthyroid patients with newly diagnosed T2DM. Higher normal FT3, TSH and impaired sensitivity to thyroid hormones are associated with increased incidence of MAFLD, being dependent on other metabolic factors.
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Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Humanos , Glândula Tireoide/diagnóstico por imagem , Tiroxina , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Testes de Função Tireóidea , Hormônios Tireóideos , Tri-Iodotironina , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Tireotropina , Cirrose Hepática , FibroseRESUMO
OBJECTIVE: To investigate DNA methylation (DNAm) status of dickkopf-associated protein 1 (DKK-1) in ossified hip capsule synovium and serum among patients with ankylosing spondylitis (AS). METHODS: Western blot was applied to detect the level of DKK-1 protein expression in hip joint capsule tissues from four patients with AS as well as four patients with femoral neck fracture (FNF) caused by trauma as control. DKK-1 gene promoter methylation (GPM) was examined by methylation-specific polymerase chain reaction. Reverse transcription-polymerase chain reaction was performed to examine the messenger RNA (mRNA) levels of DKK-1, ß-catenin, and Wnt3a in both tissue and serum. The DNAm status of serum DKK-1 was measured among 36 patients with AS and syndesmophytes (AS + syndesmophytes group), 40 patients with AS but no syndesmophyte (AS group), and 42 healthy individuals (control group). Also, the serum levels of DKK-1 were measured by enzyme-linked immunosorbent assay. The modified New York criteria (mNYC) together with the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) were adopted to examine the radiographic progression of AS. The receiver operating characteristic (ROC) curve was applied to investigate the diagnostic value of the methylation rate of DKK-1 with regard to radiographic progression. RESULTS: The expressions of DKK-1 protein and mRNA in hip joint capsule tissues of AS patients were significantly lower, while DKK-1 GPM rate, ß-catenin mRNA, and Wnt3a mRNA were markedly higher when compared with FNF group. For serum samples, the DKK-1 methylation rate was significantly higher in AS+ syndesmophytes group in contrast to AS group and healthy controls. Serum levels of DKK-1 protein and mRNA in AS with syndesmophytes group were markedly decreased, while ß-catenin mRNA and Wnt3a mRNA expressions were significantly increased than AS with no syndesmophyte group and the healthy control group. AS patients in Grade 4 showed a significantly higher serum DKK-1 GPM rate than those in Grade 3 based on mNYC. Serum DKK-1 GPM level was markedly and positively correlated with mSASSS. Serum levels of DKK-1 in AS+ syndesmophytes group were markedly lower compared with AS but no syndesmophyte group and healthy controls. ROC curve analysis indicated that serum DKK-1 methylation rate serves as a decent indicator for AS radiographic progression. CONCLUSION: DNAm of DKK-1 may correlate with pathological bone formation in AS, which may provide new strategies for the treatment of AS abnormal bone formation.
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Espondilite Anquilosante , Humanos , beta Catenina/genética , Metilação de DNA , Osteogênese , Coluna Vertebral/patologia , Espondilite Anquilosante/genéticaRESUMO
Purpose: Intravenous thrombolysis has emerged as an effective approach to improve the long-term survival and functional status of patients with ischemic stroke. The aim of this study was to assess the impact of a national stroke project on the door-to-needle-time (DNT). Patients and Methods: The patients were divided into pre-construction and construction periods. Construction Measures were performed during the construction period. The DNT and onset-to-needle time (ONT) were compared in two period groups. Results: After participating in the National Stroke Center Project and effective measurements, the thrombolysis treatment metrics were improved significantly. The DNT (IQR) was shortened from 65.0 (54.5,85.0) minutes in the Pre-Construction period to 40.0 (33.0,53.0) minutes in the Construction period (p < 0.001). Similarly, the ONT was reduced from 157.0 (IQR) (115.0,184.0) minutes to 116.0 (87.8,170.0) minutes (p = 0.035). Conclusion: The DNT time and ONT time can be shortened by National Stroke Center Construction projects. More suitable hospitals should be encouraged to participate as the National Stroke Center.
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ETHNOPHARMACOLOGICAL RELEVANCE: Pi-Pa-Run-Fei-Tang (PPRFT) is an empirical TCM prescription for treating asthma. However, the underlying mechanisms of PPRFT in asthma treatment have yet to be elucidated. Recent advances have revealed that some natural components could ameliorate asthma injury by affecting host metabolism. Untargeted metabolomics can be used to better understand the biological mechanisms underlying asthma development and identify early biomarkers that can help advance treatment. AIM OF THE STUDY: The aim of this study was to verification the efficacy of PPRFT in the treatment of asthma and to preliminarily explore its mechanism. MATERIALS AND METHODS: A mouse asthma model was built by OVA induction. Inflammatory cell in BALF was counted. The level of IL-6, IL-1ß, and TNF-α in BALF were measured. The levels of IgE in the serum and EPO, NO, SOD, GSH-Px, and MDA in the lung tissue were measured. Furthermore, pathological damage to the lung tissues was detected to evaluate the protective effects of PPRFT. The serum metabolomic profiles of PPRFT in asthmatic mice were determined by GC-MS. The regulatory effects on mechanism pathways of PPRFT in asthmatic mice were explored via immunohistochemical staining and western blotting analysis. RESULTS: PPRFT displayed lung-protective effects through decreasing oxidative stress, airway inflammation, and lung tissue damage in OVA-induced mice, which was demonstrated by decreasing inflammatory cell levels, IL-6, IL-1ß, and TNF-α levels in BALF, and IgE levels in serum, decreasing EPO, NO, and MDA levels in lung tissue, elevating SOD and GSH-Px levels in lung tissue and lung histopathological changes. In addition, PPRFT could regulate the imbalance in Th17/Treg cell ratios, suppress RORγt, and increase the expression of IL-10 and Foxp3 in the lung. Moreover, PPRFT treatment led to decreased expression of IL-6, p-JAK2/Jak2, p-STAT3/STAT3, IL-17, NF-κB, p-AKT/AKT, and p-PI3K/PI3K. Serum metabolomics analysis revealed that 35 metabolites were significantly different among different groups. Pathway enrichment analysis indicated that 31 pathways were involved. Moreover, correlation analysis and metabolic pathway analysis identified three key metabolic pathways: galactose metabolism; tricarboxylic acid cycle; and glycine, serine, and threonine metabolism. CONCLUSION: This research indicated that PPRFT treatment not only attenuates the clinical symptoms of asthma but is also involved in regulating serum metabolism. The anti-asthmatic activity of PPRFT may be associated with the regulatory effects of IL-6/JAK2/STAT3/IL-17 and PI3K/AKT/NF-κB mechanistic pathways.
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Asma , Lesão Pulmonar , Camundongos , Animais , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ovalbumina/toxicidade , Interleucina-6/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-17/metabolismo , Linfócitos T Reguladores , Modelos Animais de Doenças , Citocinas/metabolismo , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/metabolismo , Transdução de Sinais , Pulmão , Imunoglobulina E , Superóxido Dismutase/metabolismo , Camundongos Endogâmicos BALB CRESUMO
Biochar (BC) has been demonstrated the potential to activate persulfate (PS), but the limited catalytic efficiencies hindered their further application. Herein, an innovative magnetic MgFe2O4/BC (MMB) derived from pomelo peel was prepared for persulfate-based advanced oxidation process (PS-AOPs). Benefitting from the extraordinary properties, levofloxacin (LFX) was efficiently removed in the MMB/PS system. MMB700 exhibited the best catalytic activity, 87.87% of LFX was removed in the MMB700/PS system. In addition, it could maintain 67.90% of LFX degradation efficiency after 3 times of reuse. Quenching experiments, electron spin resonance (ESR) detection, and electrochemical test results indicated that both non-radical pathway and direct electron-transfer pathway advanced LFX degradation. LFX was oxidized by O2·- and 1O2, O2·- acted as the dominant active species. PS activation was induced by the active sites of MMB700. This work not only developed a promising magnetic biochar PS catalyst for antibiotics elimination, but also facilitated insights PS activation mechanisms.
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Levofloxacino , Poluentes Químicos da Água , Carvão Vegetal , Fenômenos Magnéticos , Poluentes Químicos da Água/análiseRESUMO
Nowadays, a growing number of microplastics are released into the environment due to the extensive use and inappropriate management of plastic products. With the increasing body of evidence about the pollution and hazards of microplastics, microplastics have drawn major attention from governments and the scientific community. As a kind of emerging and persistent environmental pollutants, microplastics have recently been detected on a variety of substrates in the world. Therefore, this paper reviews the recent progress in identifying the sources of microplastics in soil, water, and atmosphere and describing the transport and fate of microplastics in the terrestrial, aquatic and atmospheric ecosystems for revealing the circulation of microplastics in the ecosystem. In addition, considering the persistence of microplastics, this study elucidates the interactions of microplastics with other pollutants in the environment (i.e., organic pollutants, heavy metals) with emphasis on toxicity and accumulation, providing a novel insight into the ecological risks of microplastics in the environment. The negative impacts of microplastics on organisms and environmental health are also reviewed to reveal the environmental hazards of microplastics. The knowledge gaps and key research priorities of microplastics are identified to better understand and mitigate the environmental risks of microplastics.
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Poluentes Ambientais , Poluentes Químicos da Água , Organismos Aquáticos , Ecossistema , Monitoramento Ambiental , Microplásticos , Plásticos/toxicidade , Solo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
With rising concerns in the practical application of biochar for the remediation of environment influenced by various organic contaminants, a critical review to facilitate insights the crucial role that biochar has played in wastewater and polluted soil decontamination is urgently needed. This research therefore aimed to describe different intriguing dimensions of biochar interactions with organic contaminants, which including: (i) an introduction of biochar preparation and the related physicochemical properties, (ii) an overview of mechanisms and factors controlling the adsorption of organic contaminants onto biochar, and (iii) a summary of the challenges and an outlook of the further research needs in this issue. In the light of the survey consequences, the appearance of biochar indicates the potential in substituting the existing costly adsorbents, and it has been proved that biochar is one promising adsorbent for organic pollutants adsorption removal from water and soil. However, some research gaps, such as dynamic adsorption, potential environmental risks, interactions between biochar and soil microbes, novel modification techniques, need to be further investigated to facilitate its practical application. This research will be conductive to better understanding the adsorption removal of organic contaminants by biochar.
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Carvão Vegetal , Poluentes do Solo , Adsorção , Solo , Poluentes do Solo/análiseRESUMO
Biochar (BC) is a low-cost material rich in carbon, which is being used increasingly as a catalyst in persulfate-based advanced oxidation processes (PS-AOPs) for the remediation of groundwater and soil contaminated with organic compounds. In this work, a general summary of preparation methods and applications of various BC (i.e., pristine BC, magnetic BC, and chemically modified BC) in PS-AOPs is presented. Different influence factors (e.g., pH, anions, natural organic matter) for the degradation of organic compounds are discussed. Meanwhile, the influence of external energy (e.g., solar irradiation, UV-Vis, ultrasonic) is also mentioned. Furthermore, the advantage of different BC in PS-AOPs are compared. Finally, potential problems, challenges, and prospects in the application of biochar-persulfate based advanced oxidation processes (BCPS-AOPs) are discussed in the conclusion and perspective.
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Água Subterrânea , Poluentes Químicos da Água , Carvão Vegetal/química , Compostos Orgânicos , Oxirredução , Solo , Poluentes Químicos da Água/análiseRESUMO
Neonicotinoid insecticides (NIs) have been widely detected in environmental media and human body with concentrations reaching hundreds of nanomolar to micromolar levels. However, the information about their human health toxicology and mechanism is deficient. Previous studies have implied that NIs might exert estrogenic disruption and promote breast cancer progression, but the molecular mechanism is unclear, especially the molecular initiating event. G protein-coupled estrogen receptor (GPER), as a candidate therapeutic target, plays vital roles in the development of breast cancer. This work aimed to reveal the potential mechanism through GPER pathway. Firstly, we screened the activities of seven most common NIs on GPER signal pathway by calcium mobilization assay. Clothianidin, acetamiprid (ACE), and dinotefuran activated GPER most potently and ACE displayed the highest agonistic activity with the lowest observed effective concentration (LOEC) of 1 µM. The molecular docking and dynamics simulation showed favored interaction trend between the NIs and GPER. The three NIs with GPER activity induced 4T1 breast cancer cells migration and ACE showed the highest potency with LOEC of 100 nM. ACE also induced 4T1 cells proliferation at high concentration of 50 µM and up-regulated GPER expression in a dose-dependent manner. We speculated that both the induction effects of ACE on 4T1 cells proliferation and migration might be owing to the activation and up-regulation of GPER. By using 4T1-Luc cells injected orthotopic tumor model, we found that ACE also promoted in-situ breast cancer growth and lung metastasis in normal mouse dependent on GPER. However, ACE only promoted in-situ breast cancer growth through GPER but not lung metastasis in ovariectomized mice, implying that the ACE-induced lung metastasis should be related to endogenous estrogen from ovary. Overall, we demonstrated that NIs promoted breast cancer progression via GPER pathway at human related exposure levels and their female health risks need urgent concerns.
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Neoplasias , Receptores de Estrogênio , Humanos , Feminino , Camundongos , Animais , Simulação de Acoplamento Molecular , Estrogênios , Proteínas de Ligação ao GTPRESUMO
The limitation of low efficiency and complicated separation after adsorption make the practical application of biochar a huge challenge. Here, one pomelo peel-derived magnetic biochar composite, biochar supported MgFe2O4 (BMF) was fabricated and adopted for Levofloxacin (LFX) adsorption. Adsorption behaviors and mechanisms were investigated by characterization analysis, batch experiments, and data modeling. Results indicated that adsorption could be strikingly influenced by pyrolysis temperature. Adsorption kinetic was well fitted by pseudo-second-order model. Adsorption isotherm was best fitted with Freundlich model. The maximum adsorption capacity was 115 mg g-1. Moreover, hydrophobic effect played a limited contribution according to dual-mode model analysis. LFX adsorption was spontaneous and endothermic. Adsorption mechanisms were ascribed to electrostatic interactions, H-bonding, functional groups complexation, and π-π electron donor-acceptor interactions. Besides that, BMF had the potential for repeated use. This research proposed a novel and promising method for LFX or other antibiotics adsorption removal.
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Levofloxacino , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , CinéticaRESUMO
The widespread of polybrominated diphenyl ethers (PBDEs) in the environment has caused rising concerns, and it is an urgent endeavor to find a proper way for PBDEs remediation. Various techniques such as adsorption, hydrothermal and thermal treatment, photolysis, photocatalytic degradation, reductive debromination, advanced oxidation processes (AOPs) and biological degradation have been developed for PBDEs decontamination. A comprehensive review of different PBDEs remediation techniques is urgently needed. This work focused on the environmental source and occurrence of PBDEs, their removal and degradation methods from water and soil, and prospects for PBDEs remediation techniques. According to the up-to-date literature obtained from Web of Science, it could be concluded that (i) photocatalysis and photocatalytic degradation is the most widely reported method for PBDEs remediation, (ii) BDE-47 and BDE-209 are the most investigated PBDE congeners, (iii) considering the recalcitrance nature of PBDEs and more toxic intermediates could be generated because of incomplete degradation, the combination of different techniques is the most potential solution for PBDEs removal, (iv) further researches about the development of novel and effective PBDEs remediation techniques are still needed. This review provides the latest knowledge on PBDEs remediation techniques, as well as future research needs according to the up-to-date literature.
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This study aimed to investigate the effects of red mud-based-passivator (RM-based-passivator) on rice yield, cadmium (Cd) in brown rice, pH and available Cd in Cd-polluted soil by pot experiments, and to explore the adsorption mechanism of the passivator by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis. The results showed that this passivator obviously improved the pH, reduced the available Cd in soil and the Cd content in brown rice in Changsha Cd polluted soil (CS soil), while had little effect on Hengyang Cd polluted soil (HY soil). Compared with the control, the soil pH increased in the range from 0.31 to 1.37, the available Cd in soil decreased in the range from 13.25% to 52.34%, and the total Cd in brown rice decreased in the range from 46.44% to 84.98% in CS soil. Considering the impacts of RM-based-passivator on the growth of rice, the Cd content in brown rice, and the pH and available Cd in soil, 0.10-0.30% (w/w) of the passivator is recommended to apply in CS soil but not in HY soil. Based on the analysis of SEM, EDX, FTIR and XRD, the mechanism of Cd(II) adsorption by RM-based-passivator included physical adsorption, surface complexation and ion exchange. The present results indicated that the appropriate addition of RM-based-passivator could be an effective strategy for the remediation of acidic Cd-polluted soils.