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1.
Analyst ; 149(13): 3651-3660, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38814120

RESUMEN

Monitoring methods for beta-lactam (ß-lactam) antibiotics, especially for ampicillin (AMP), with simple operation and sensitivity for realtime applications are highly required. To address this need, antioxidant carbon dots (E-CDs) with excellent fluorescence properties were synthesized using citric acid and ethylenediamine as raw materials. With a quantum yield of 81.97%, E-CDs exhibited a specific and sensitive response to ˙OH. The quenched fluorescence of E-CDs by the formed ˙OH could be restored through a competition reaction with AMP. Leveraging the signal-quenching strategy of E-CDs, H2O2, and Fe2+, a fluorescence signal-on strategy was developed using AMP as the fluorescence recovery agent for the sensitive detection of AMP. The mechanism of the quenching of E-CDs by ˙OH was attributed to the damaging effect of ˙OH on E-CDs. Under optimal conditions, the detection limit of this method for AMP was determined to be 0.38 µg mL-1. This method was successful in drug quality control and the spiked detection of AMP in lake water, milk, and sea cucumber, presenting a viable option for convenient and rapid antibiotic monitoring methods.


Asunto(s)
Ampicilina , Carbono , Límite de Detección , Puntos Cuánticos , Espectrometría de Fluorescencia , Carbono/química , Ampicilina/análisis , Ampicilina/química , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Animales , Antioxidantes/análisis , Antioxidantes/química , Leche/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Radical Hidroxilo/química , Radical Hidroxilo/análisis , Antibacterianos/análisis , Antibacterianos/química , Colorantes Fluorescentes/química , Ácido Cítrico/química , Fluorescencia , Etilenodiaminas
2.
Int J Neurosci ; 133(12): 1411-1423, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35633062

RESUMEN

Backgroud: Hydroxysafflor yellow A (HSYA) has a certain improvement effect on Alzheimer's disease (AD) rats, but its specific mechanism is still unclear. The purpose of this study was to observe the regulatory effect of HSYA on learning and memory ability of AD rats induced by Aß1-42.Materials and methods: Morris water maze test was used to evaluate the effect of HSYA on the learning and memory ability of AD model rats. To explore the effective targets and potential molecular mechanisms of HSYA in AD treatment based on quantitative proteomics.Results: Through the Morris water maze experiment, we found that after HSYA treatment, the learning ability of rats in the model group has been significantly improved. Quantitative proteomics results showed that among the 11 common differential proteins between the "model/sham operation" comparison group and the "HSYA treatment/model" comparison group, the cholesterol synthesis rate-limiting enzyme mevalonate decarboxylase (Mvd) Western Blot results are consistent with the results of quantitative proteomics analysis. We found that HSYA can inhibit the expression of BACE protein in hippocampus of AD rats and decrease the level of Aß1-42. Besides, HSYA could also reduce cholesterol levels in serum and hippocampus.Conclusion: In summary, HSYA can effectively improve learning and memory disorders in AD rats, and exert neuroprotective effects by effectively controlling serum and brain cholesterol to down-regulate the expression of BACE and thus reduce the content of Aß1-42.


Asunto(s)
Enfermedad de Alzheimer , Ratas , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Proteómica , Aprendizaje por Laberinto , Encéfalo
3.
Neurochem Res ; 47(3): 748-761, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34783973

RESUMEN

Hydroxysafflor yellow A (HSYA) is an extract from Carthamus tinctorius L. dry flowers (Compositae). HSYA has been shown to have neuroprotective effects on several Alzheimer's disease (AD) models. However, the exact mechanisms by which HSYA regulates neuroinflammation have still not been clarified. In this study, we investigated the mechanism by which HSYA regulates microglial activation and neuroinflammation via TREM2, and further clarified its underlying molecular mechanism. We silenced TREM2 in BV-2 cells and evaluated the expression of inflammatory markers (TNF-α, IL-1ß, IL-4, IL-6, IL-10, and IL-13). The results showed that HSYA could up-regulate cell viability and improve the morphology of BV-2 cells injured by Aß1-42. The results showed that Aß1-42 could induce microglia to upregulate the expression of M1 markers (iNOS, IL-1ß, IL-6) and downregulate M2 marker (Arg-1, IL-4, IL-10, IL-13) expression. HSYA reversed the effects of Aß1-42 via TREM2, switching microglia from an M1 proinflammatory phenotype to an M2 anti-inflammatory phenotype. HSYA inhibited the Aß1-42-induced activation of the TLR4/NF-κB transduction pathway by upregulating TREM2 and regulated the transcription of inflammatory cytokines via the downstream transcription factors NF-κB p65 and IκB-α. In conclusion, HSYA regulated the microglial inflammatory phenotype by regulating microglial (M1/M2) polarization in Aß1-42-induced BV-2 cells which may be mediated by the TREM2/TLR4/NF-κB pathway.


Asunto(s)
Microglía , FN-kappa B , Péptidos beta-Amiloides , Animales , Chalcona/análogos & derivados , Glicoproteínas de Membrana/metabolismo , Ratones , Microglía/metabolismo , FN-kappa B/metabolismo , Enfermedades Neuroinflamatorias , Fragmentos de Péptidos , Fenotipo , Quinonas , Receptores Inmunológicos/metabolismo , Transducción de Señal , Receptor Toll-Like 4/metabolismo
4.
Mediators Inflamm ; 2022: 5463505, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186576

RESUMEN

Objective: Long non-coding RNAs (lncRNAs) play many important roles in gene regulation and disease pathogenesis. Here, we sought to determine that mitochondrial dynamic related lncRNA (MDRL) modulates NLRP3 inflammasome activation and apoptosis of vascular smooth muscle cells (VSMCs) and protects arteries against atherosclerosis. Methods: In vivo experiments, we applied LDLR knockout (LDLR-/-) mice fed the high-fat diet to investigate the effects of MDRL on atherosclerosis. In vitro experiments, we applied mouse aortic smooth muscle cells to determine the mechanism of MDRL in abrogating NLRP3 inflammasome and inhibiting cell apoptosis through miR-361/sequentosome 1 (SQSTM1) by TUNEL staining, quantitative RT-PCR, western blot, microribonucleoprotein immunoprecipitation, and luciferase reporter assay. Results: Downregulated MDRL and increased NLRP3 were observed in mouse atherosclerotic plaques, accompanied with the increase of miR-361. The results showed that MDRL overexpression significantly attenuated the burden of atherosclerotic plaque and facilitated plaque stability through inhibiting NLRP3 inflammasome activation and cell apoptosis, and vice versa. Mechanically, MDRL suppressed NLRP3 inflammasome activation and VSMC apoptosis via suppressing miR-361. Furthermore, miR-361 directly bound to the 3'UTR of SQSTM1 and inhibited its translation, subsequently activating NLRP3 inflammasome. Systematic delivery of miR-361 partly counteracted the beneficial effects of MDRL overexpression on atherosclerotic development in LDLR-/- mice. Conclusions: In summary, MDRL alleviates NLRP3 inflammasome activation and apoptosis in VSMCs through miR-361/SQSTM1/NLRP3 pathway during atherogenesis. These data indicate that MDRL and inhibition of miR-361 represent potential therapeutic targets in atherosclerosis-related diseases.


Asunto(s)
Aterosclerosis , MicroARNs , Placa Aterosclerótica , ARN Largo no Codificante , Regiones no Traducidas 3' , Animales , Aterosclerosis/metabolismo , Inflamasomas/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Dinámicas Mitocondriales , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Placa Aterosclerótica/metabolismo , ARN Largo no Codificante/genética , Proteína Sequestosoma-1/genética , Proteína Sequestosoma-1/metabolismo
5.
Anal Bioanal Chem ; 413(6): 1605-1614, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33515273

RESUMEN

Effective and simultaneous monitoring of the abnormal expression of certain microRNAs (miRNAs), especially for miRNA-21 and miRNA-155, can indicate drug resistance in lung cancer. In this work, T7 exonuclease (T7 Exo)-assisted target recycling amplification coupled with the extensive fluorescence quenching of graphene oxide (GO) was designed for the simultaneous detection of miRNA-21 and miRNA-155 using FAM- and ROX-labeled single-strand DNA probes. Through this method, the variable emission intensities of FAM and ROX caused by the introduction of miRNA-21 and miRNA-155, respectively, were obtained with high sensitivity. The method exhibited excellent analytical performance for simultaneous detection of miRNA-21 and miRNA-155 without cross-interference. The linear range was from 0.005 nM to 5 nM over three orders of magnitude, with detection limits as low as 3.2 pM and 4.5 pM for miRNA-21 and miRNA-155, respectively. Furthermore, the recovery (92.49-103.67%) and relative standard deviation (RSD < 4.8%) of the standard addition test of miRNA-21 and miRNA-155 in human plasma suggested the potential for drug resistance warning in clinical practice via this simple strategy. A homogeneous T7 Exo-assisted signal amplification combined with GO quenching platform was developed for accurate, sensitive and simultaneous analysis of miRNA-21 and miRNA-155 for drug resistance warning in lung cancer. This simple method exhibited a wide linear range and low LODs for miR-21 and miR-155.


Asunto(s)
Técnicas Biosensibles , Exodesoxirribonucleasas/metabolismo , Neoplasias Pulmonares/sangre , MicroARNs/análisis , Sondas de ADN/química , Polarización de Fluorescencia , Grafito/química , Humanos , Límite de Detección , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Técnicas de Amplificación de Ácido Nucleico/métodos , Plasma/metabolismo , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia/métodos
6.
Metab Brain Dis ; 36(4): 557-569, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33550459

RESUMEN

Alzheimer's disease (AD) is an aggressive neurodegenerative disease associated with cognitive decline, memory, language, and visual-spatial coordination disorders that eventually lead to complete loss of basic function. Hypercholesterolemia plays an important role in the pathogenesis of AD and its related diseases. Safflower yellow (SY) is a natural chalcone compound isolated from safflower, which has the effect of antioxidation and weight loss. Previous studies have shown that SY has a significant improvement in learning and memory in various AD model animals. In the early stage of proteomic technology, we found that the cholesterol synthesis rate-limiting enzyme Mevalonate decarboxylase (MVD) was abnormally high in dementia rats, and the expression level of MVD decreased after SY treatment. We speculated that SY may improve the learning and memory ability of AD mice by affecting cholesterol metabolism. The purpose of this study was to evaluate the effect of SY on regulating cholesterol metabolism and improving dementia. The area of amyloid-ß (Aß) plaque in the brain of APP/PS1 mice and various blood biochemical and molecular biological indexes was detected. Through behavioral experiments, we found that APP/ PS1 mice had significant learning and memory impairment compared with wild type mice(P < 0.01). SY (30 mg/kg) treatment for 1 month can significantly improve the learning and memory ability of APP/PS1 mice (P < 0.01). Our results showed that SY decreased serum Total cholesterol (TC) and Triglyceride (TG) and increased the level of High-density lipoprotein (HDL). HE staining obscured that SY affect the changes of liver tissue in APP/PS1 mice (P < 0.05 and P < 0.01). We found that SY reduced the expression of MVD and Apolipoprotein E (APOE4) in the cortex (P < 0.05 and P < 0.01). In summary, SY can effectively control cholesterol in serum and brain and change the degeneration of liver tissue. SY improves Alzheimer's disease by lowering serum, cortex and cortical cholesterol.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide , Encéfalo/metabolismo , Chalcona/análogos & derivados , Colesterol/metabolismo , Presenilina-1 , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Anticolesterolemiantes/farmacología , Anticolesterolemiantes/uso terapéutico , Reacción de Prevención/efectos de los fármacos , Reacción de Prevención/fisiología , Encéfalo/efectos de los fármacos , Chalcona/farmacología , Chalcona/uso terapéutico , Colesterol/sangre , Femenino , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Transgénicos , Presenilina-1/genética
7.
Chem Pharm Bull (Tokyo) ; 68(7): 628-634, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32336694

RESUMEN

Facile and effective detection of dopamine (DA) plays a significant role in current clinical applications. Substantially, special optical nanomaterials are important for fabricating easy-to-control, cheap, selective, and portable fluorescence DA sensors with superior performance. Herein, carbon dots (CDs) prepared from melting method were applied as signal to establish a simple but effective fluorescence strategy for DA determination based on the enzymatic activity of acid phosphatase (ACP), which induces DA to form polydopamine (pDA). The formed pDA caused by the enzymatic oxidization of ACP toward DA can interact with CDs through the inner filter effect. Such behavior effectively quenched the CDs' fluorescence. The degree of fluorescence quenching of CDs was positively correlated with the DA content. Under the optimized reaction conditions, the proposed fluorescence method exhibited a comparable analytical performance with other DA sensors with good selectivity. Furthermore, this method has been successfully applied to detect DA in DA hydrochloride injection and human serum samples. It shows that this method features potential practical application value and is expected to be used in clinical research.


Asunto(s)
Fosfatasa Ácida/metabolismo , Dopamina/análisis , Dopamina/metabolismo , Fluorescencia , Indoles/metabolismo , Polímeros/metabolismo , Fosfatasa Ácida/química , Carbono/química , Indoles/química , Oxidación-Reducción , Tamaño de la Partícula , Polímeros/química , Puntos Cuánticos/química , Espectrometría de Fluorescencia , Propiedades de Superficie
8.
Anal Chem ; 91(7): 4552-4558, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30838849

RESUMEN

As an alternative to most of the reported nucleic acid amplification-based electrochemical DNA biosensors used for detection of trace levels of genomic DNA, we herein present a novel detection concept. The proposed system involves the conversion of two short double-stranded DNAs (dsDNAs), labeled with a thiol-tag or biotin-tag, into a single integrated dsDNA containing thiol and biotin at both terminals in the presence of target DNA through ligase chain reaction (LCR) and followed by the immobilization of these integrated dsDNAs on a bovine serum albumin (BSA)-modified gold electrode surface. Owing to rapid depletion of the two short dsDNAs via LCR, the integrated dsDNAs were generated in an exponential manner so that this sensoring approach offered a limit of detection of 25 yoctomoles (15 copies in 50 µL sample volumes), a high discrimination of single-base mismatch and a wide linear concentration range (across 6 orders of magnitude) for target DNA. Significantly, the proposed sensor, which has simplicity in operation and ease of miniaturization, detected the target of interest in total nucleic acid extracts derived from clinical serum samples with excellent results, thereby demonstrating its considerable diagnostic potential in fields ranging from virus detection to the diagnosis of genetic diseases.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/sangre , Genoma Humano , Animales , Bovinos , ADN/metabolismo , Técnicas Electroquímicas , Electrodos , Oro/química , Humanos , Técnicas de Amplificación de Ácido Nucleico , Polimorfismo de Nucleótido Simple , Albúmina Sérica Bovina/química
9.
Mikrochim Acta ; 185(5): 260, 2018 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-29680977

RESUMEN

Amino-modified carbon dots (C-dots) with positively charged surface were prepared. They display strong blue fluorescence and are shown to act as quenchers of the green fluorescence of FAM-labeled ssDNA such as the F-probe used in this work that was immobilized on the C-dots. On the addition of highly negatively charged heparin (Hep), it will interact with the C-dots and displace the F-probe from C-dots. Once the F-probe is displaced by Hep, its green fluorescence is restored. The intrinsic blue fluorescence of the C-dots remains stable after addition of Hep. Thus, a signal-on ratiometric fluorometric assay was developed for the ultra-sensitive detection of Hep. The underlying mechanisms of quenching and recovery are discussed. Under optimized conditions, the recovery of the ratiometric fluorescence of the system composed of C-dots and quenched F-probe is proportional to the Hep concentration in the range of 0.01-2.0 µg·mL-1 (= 0.00125-0.25 U·mL-1). The method was successfully applied to the determination of Hep in spiked serum samples. Graphical abstract Schematic of a signal-on ratiometric fluorometric method for the ultra-sensitive detection of heparin on the basis of the displacement and fluorescence enhancement of adsorbed FAM-labeled ssDNA from amino-modified carbon dots (C-dots) by heparin.


Asunto(s)
Bioensayo , Carbono/química , Fluorometría , Heparina/análisis , Animales , ADN , Colorantes Fluorescentes , Fluorometría/métodos , Heparina/sangre , Límite de Detección , Puntos Cuánticos , Conejos
10.
Entropy (Basel) ; 20(11)2018 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-33266546

RESUMEN

Based on the reversible heat engine model, theoretical analysis is carried out for economic performance of a solar tower power plant (STPP) combined with multi-effect desalination (MED). Taking total revenue of the output power and the fresh water yield per unit investment cost as the economic objective function, the most economical working condition of the system is given by analyzing the influence of the system investment composition, the receiver operating temperature, the concentration ratio, the efficiency of the endoreversible heat engine, and the relative water price on the economic parameters of the system. The variation curves of the economic objective function are given out when the main parameter is changed. The results show that the ratio of water price to electricity price, or relative price index, has a significant impact on system economy. When the water price is relatively low, with the effect numbers of the desalination system increasing, and the economic efficiency of the overall system worsens. Only when the price of fresh water rises to a certain value does it make sense to increase the effect. Additionally, the threshold of the fresh water price to the electricity price ratio is 0.22. Under the conditions of the current price index and the heliostat (or reflector), the cost ratio and the system economy can be maximized by selecting the optimum receiver temperature, the endoreversible heat engine efficiency, and the optimum concentration ratio. Given the receiver surface temperature and the endoreversible heat engine efficiency, increasing the system concentration ratio of the heliostat will be in favor of the system economy.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 834-7, 2016 Mar.
Artículo en Zh | MEDLINE | ID: mdl-27400533

RESUMEN

Wuchang rice is a geographical indication product in China. Due to its high quality and low production, the phenome- non of fake is more and more serious. An effective identification method of Wuchang rice is urgent needed, for the maintenance of its brand image and interest of consumers. Base on the content of inorganic elements which are analyzed by ICP-AES and ICP-MS in rice, the identification model of Wuchang rice is studied combining with principal component analysis (PCA), Fisher discrimination and artificial neural network (ANN) in this paper. The effect on the identification of samples is poor through PCA, while the samples from Wuchang area and other areas can be identified accurately through Fisher discrimination and ANN. The average accurate identification ratio of training and verification set through Fisher discrimination is 93.5%, while the average accurate identification ratio through ANN is 96.4%. The ability to identify of ANN is better than Fisher discrimination. Wuchang rice can be identified accurately through the result of this research which provides a technology for the protection of geographical indications of this product.


Asunto(s)
Oryza/química , Análisis Espectral , China , Geografía , Espectrometría de Masas , Redes Neurales de la Computación , Análisis de Componente Principal
12.
Anal Bioanal Chem ; 407(20): 6071-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26025552

RESUMEN

High-internal-phase-emulsion polymers (polyHIPEs) show great promise as solid-phase-extraction (SPE) materials because of the tremendous porosity and highly interconnected framework afforded by the high-internal-phase-emulsion (HIPE) technique. In this work, polyHIPE monolithic columns as novel SPE materials were prepared and applied to trace enrichment of cytokinins (CKs) from complex plant samples. The polyHIPE monoliths were synthesized via the in-situ polymerization of the continuous phase of a HIPE containing styrene (STY) and divinylbenzene (DVB) in a stainless column, and revealed highly efficient and selective enrichment ability for aromatic compounds. Under the optimized experimental conditions, a method using a monolithic polyHIPE column combined with liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) was developed for the simultaneous extraction and sensitive determination of trans-zeatin (tZ), meta-topolin (mT), kinetin (K), and kinetin riboside (KR). The proposed method had good linearity, with correlation coefficients (R (2)) from 0.9957 to 0.9984, and low detection limits (LODs, S/N = 3) in the range 2.4-47 pg mL(-1) for the four CKs. The method was successfully applied to the determination of CKs in real plant samples, and obtained good recoveries ranging from 68.8 % to 103.0 % and relative standard deviations (RSDs) lower than 16 %.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Citocininas/análisis , Fabaceae/química , Nicotiana/química , Extracción en Fase Sólida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Citocininas/aislamiento & purificación , Emulsiones/química , Límite de Detección , Hojas de la Planta/química , Polímeros/química , Estirenos/química , Espectrometría de Masas en Tándem/métodos , Compuestos de Vinilo/química
13.
Sci Total Environ ; 926: 171709, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38494016

RESUMEN

Acid mine drainage (AMD) contains high concentrations of heavy metals, causing serious environmental pollution. Current neutralization techniques fail to recover and utilize valuable heavy metals, and generate large quantities of hazardous sludge. Manganese (Mn) is generally present at high levels in AMD. Therefore, this paper proposed a technology to recover Mn from AMD, by adding KMnO4 to converting Mn into ε-MnO2. Ultra-Violet C (UVC) was used to photolyze the residual KMnO4. The study then evaluated the processes and mechanisms involved in the technology. The photolysis of KMnO4 in strong acidic conditions was determined, and new mechanisms were proposed. MnO2 produced by the photolysis process was formed through the reaction between Mn(III) and KMnO4. In the absence of KMnO4, Mn(III) underwent further photolysis and was reduced to Mn2+. The maximum adsorption capacities of in-situ formed ε-MnO2 for Pb2+, Cd2+, and Fe3+ were 449.80, 122.05, and 779.88 mg/g, respectively. Higher Mn-OH levels and MnO2 regeneration were crucial in improving adsorption performance. Proton exchange and inner-circle complexation were the main pathways for Pb2+ and Cd2+ adsorption by in-situ formed ε-MnO2. A phase transformation occurred when a substantial amount of Fe3+ was adsorbed, leading to the gradual transformation to MnFe binary oxides. When applying in-situ formed ε-MnO2 technology for actual AMD treatment, 98.62 % of Mn in AMD was recovered within 24 h in the presence of ε-MnO2 for possible further reuse in industries, with a final recovery of 0.76 kg/m3. Further, this technique removed other heavy metals and reduced the sludge volume by 20.99 % when used as a pre-treatment step for neutralization. These results demonstrated the broad potential of this treatment technology.

14.
Sci Total Environ ; 930: 172844, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38685420

RESUMEN

Schwertmannite has attracted increasing interest for its excellent sorption of oxyanions such as AsO43-, CrO42-, and Sb(OH)6-. Controlling biomineralization by adjusting the Fe(II) oxidation rate and implementing alkali control can enhance the yield and adsorption performance of schwertmannite. However, the adsorption improvement mechanism is still unclear. The morphology, crystallinity, specific surface area (SSA) and oxyanion adsorption of schwertmannite synthesized with alkali control of solution pH and different Fe(II) oxidation rates were analyzed in this study. The differences in the adsorption mechanisms of As(V), Cr(VI) and Sb(V) on schwertmannite obtained under different synthesis conditions were also studied. Reducing the Fe(II) oxidation rate or maintaining the solution pH through alkali control significantly increased the SSA of schwertmannite and the proportion of outer-sphere sulfate. Alkali-controlled schwertmannite (Sch-C) exhibited superior As(V) and Sb(V) adsorption performance and slightly greater Cr(VI) adsorption than non-alkali-controlled schwertmannite. The As(V) and Sb(V) adsorption capacities of Sch-C greatly improved because the ultra-high SSA increased the surface hydroxyl content and reduced the passivation effect of amorphous precipitates on the mineral surface, allowing continuous sulfate exchange at inner mineral sites. An increased surface hydroxyl content had little effect on Cr(VI) adsorption, but an increased proportion of outer-sphere sulfate caused a slight increase in Cr(VI) adsorption. Sb(V) has a stronger hydroxyl exchange ability than As(V), but due to its octahedral structure, it exchanges only with outer-sphere sulfate on schwertmannite and hardly exchanges with inner-sphere sulfate.

15.
Sci Total Environ ; 934: 173136, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38734110

RESUMEN

Acid mine drainage (AMD) has global significance due to its low pH and elevated heavy metal content, which have received widespread attention. After AMD irrigation in mining areas, heavy metals are distributed among soil layers, but the influencing factors and mechanisms remain unclear. AMD contamination of surrounding soil is primarily attributed to surface runoff and irrigation and causes significant environmental degradation. A laboratory soil column experiment was conducted to investigate the temporal and spatial distribution of the heavy metals Cd and Cu, as well as the impact of key environmental factors on the migration and transformation of these heavy metals following long-term soil pollution by AMD. After AMD addition, the soil exhibited a significant increase in acidity, accompanied by notable alterations in various environmental parameters, including soil pH, Eh, Fe(II) content, and iron oxide content. Over time, Cd and Cu in the soil mainly existed in the exchangeable and carbonate-bound fractions. In spatial terms, exchangeable Cu increased with increasing depth. Pearson correlation analysis indicated significant negative correlations between pH and Cu, Cd, and Eh in pore water, as well as negative correlations between pH and the exchangeable fraction of Cd (F1), carbonate-bound fraction of Cd (F2), and exchangeable fraction of Cu (F1) in the solid phase. Additionally, a positive correlation was observed between pH and the residual fraction of Cu (F5). Furthermore, the soil total Cd content exhibited a positive correlation with pyrophosphate-Fe (Fep) and dithionite-Fe (Fed), while CdF1, CdF2, total Cu, and CuF1 displayed positive correlations with Fep. Our findings indicate that the presence of AMD in soil leads to alterations in the chemical fractions of Cd and Cu, resulting in enhanced bioavailability. These results offer valuable insights for developing effective remediation strategies for soils near mining sites.

17.
Environ Sci Pollut Res Int ; 31(13): 20665-20677, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38381288

RESUMEN

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


Asunto(s)
Ácidos Linoleicos Conjugados , Metales Pesados , Contaminantes Químicos del Agua , Cadmio , Micelas , Agua , Plomo , Metales Pesados/química , Adsorción , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , Cinética
18.
Heliyon ; 10(2): e24778, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38304845

RESUMEN

In this study, the therapeutic effect and possible mechanism of the total biflavonoid extract of Selaginella doederleinii Hieron (SDTBE) against cervical cancer were originally investigated in vitro and in vivo. First, the inhibition of SDTBE on proliferation of cervical cancer HeLa cells was evaluated, followed by morphological observation with AO/EB staining, Annexin V/PI assay, and autophagic flux monitoring to evaluate the possible effect of SDTBE on cell apoptosis and autophagy. Cell cycle, as well as mitochondrial membrane potential (ΔÑ°m), was detected with flow cytometry. Further, the apoptosis related protein expression and the autophagy related gene LC3 mRNA transcription level were analyzed by Western blot (WB) and real-time quantitative polymerase chain reaction (RT-qPCR), respectively. Finally, the anti-cervical cancer effect of the SDTBE was also validated in vivo in HeLa cells grafts mice. As results, SDTBE inhibited HeLa cells proliferation with the IC50 values of 49.05 ± 6.76 and 44.14 ± 4.75 µg/mL for 48 and 72 h treatment, respectively. The extract caused mitochondrial ΔÑ° loss, induced cell apoptosis by upregulating Bax, downregulating Bcl-2, activating Caspase-9 and Caspase-3, promoting cell autophagy and blocking the cell cycle in G0/G1 phase. Furthermore, 100, 200, and 300 mg/kg SDTBE suppressed the growth of HeLa cells xenografts in mice with the mean inhibition rates, 25.3 %, 57.5 % and 62.9 %, respectively, and the change of apoptosis related proteins and microvascular density was confirmed in xenografts by immunohistochemistry analysis. The results show that SDTBE possesses anti-cervical cancer effect, and the mechanism involves in activating Caspase-dependent mitochondrial apoptosis pathway.

19.
J AOAC Int ; 96(5): 1048-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24282945

RESUMEN

A discrimination method based on polyalcohol determination was developed for authenticity of protected geographical indication (PGI) vinegars-Shanxi extra aged vinegar (SVs) in China. Six polyalcohols in vinegars including erythritol, arabitol, xylitol, inositol, mannitol, and sorbitol were selected as the PGI discriminators. GC/MS was used to analyze the polyalcohols in the SVs, Zhenjiang vinegars (ZVs), Kazuo aged vinegars (KVs), and other non-geographical indication protected vinegars (NVs). SVs can be distinguished from KVs by the chemical markers mannitol and sorbitol, although the production processes for both types of vinegars are similar. Principal component analysis (PCA) was used to distinguish SVs from ZVs and NVs. The differences among the three kinds of vinegars shown by PCA results may be due to the higher erythritol content in SVs, and the inositol and mannitol in ZVs. This study also found that the amount of polyalcohols in Chinese vinegars increases with the acidity value only, regardless of the aging time. The overall results indicated that the polyalcohols can be practicable discriminators for SV discrimination.


Asunto(s)
Ácido Acético/análisis , Alcoholes del Azúcar/análisis , Eritritol/análisis , Inositol/análisis , Manitol/análisis , Sorbitol/análisis , Xilitol/análisis
20.
ACS Appl Mater Interfaces ; 15(29): 35024-35033, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37438943

RESUMEN

X-ray computed tomography (CT) is a noninvasive, nondestructive approach to imaging materials, material systems, and engineered components in two and three dimensions. Acquisition of three-dimensional (3D) images requires the collection of hundreds or thousands of through-thickness X-ray radiographic images from different angles. Such 3D data acquisition strategies commonly involve suboptimal temporal sampling for in situ and operando studies (4D imaging). Herein, we introduce a sparse-view imaging approach, Tomo-NeRF, which is capable of reconstructing high-fidelity 3D images from <10 two-dimensional radiographic images. Experimental 2D and 3D X-ray images were used to test the reconstruction capability in two-view, four-view, and six-view scenarios. Tomo-NeRF is capable of reconstructing 3D images with a structural similarity of 0.9971-0.9975 and a voxel-wise accuracy of 81.83-89.59% from 2D experimentally obtained images. The reconstruction accuracy for the experimentally obtained images is less than the synthetic structures. Experimentally obtained images demonstrate a similarity of 0.9973-0.9984 and a voxel-wise accuracy of 84.31-95.77%.

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