Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
1.
Small ; : e2402255, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837847

RESUMO

The application of electrically conductive 1D coordination polymers (1D CPs) in nanoelectronic molecular recognition is theoretically promising yet rarely explored due to the challenges in their synthesis and optimization of electrical properties. In this regard, two tetrathiafulvalene-based 1D CPs, namely [Co(m-H2TTFTB)(DMF)2(H2O)]n (Co-m-TTFTB), and {[Ni(m-H2TTFTB)(CH3CH2OH)1.5(H2O)1.5]·(H2O)0.5}n (Ni-m-TTFTB) are successfully constructed. The shorter S···S contacts between the [M(solvent)3(m-H2TTFTB)]n chains contribute to a significant improvement in their electrical conductivities. The powder X-ray diffraction (PXRD) under different organic solvents reveals the flexible and dynamic structural characteristic of M-m-TTFTB, which, combined with the 1D morphology, lead to their excellent performance for sensitive detection of volatile organic compounds. Co-m-TTFTB achieves a limit of detection for ethanol vapor down to 0.5 ppm, which is superior to the state-of-the-art chemiresistive sensors based on metal-organic frameworks or organic polymers at room temperature. In situ diffuse reflectance infrared Fourier transform spectroscopy, PXRD measurements and density functional theory calculations reveal the molecular insertion sensing mechanism and the corresponding structure-function relationship. This work expands the applicable scenario of 1D CPs and opens a new realm of 1D CP-based nanoelectronic sensors for highly sensitive room temperature gas detection.

2.
Chemistry ; 29(16): e202203432, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36567623

RESUMO

The size effect on nanoparticles, which affects the catalysis performance in a significant way, is crucial. The tuning of oxygen vacancies on metal-oxide support can help reduce the size of the particles in active clusters of Pt, thus improving catalysis performance of the supported catalyst. Herein, Ce-Sn solid solutions (CSO) with abundant oxygen vacancies have been synthesized. Activated by simple CO reduction after loading Pt species, the catalytic CO oxidation performance of Pt/CSO was significantly better than that of Pt/CeO2 . The reasons for the elevated activity were further explored regarding ionic Pt single sites being transformed into active Pt clusters after CO reduction. Due to more exposed oxygen vacancies, much smaller Pt clusters were created on CSO (ca. 1.2 nm) than on CeO2 (ca. 1.8 nm). Consequently, more exposed active Pt clusters significantly improved the ability to activate oxygen and directly translated to the higher catalytic oxidation performance of activated Pt/CSO catalysts in vehicle emission control applications.

3.
Langmuir ; 39(22): 7566-7577, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078889

RESUMO

This study was to develop a low-cost N-doped porous biocarbon adsorbent that can directly adsorb CO2 in high-temperature flue gas from fossil fuel combustion. The porous biocarbon was prepared by nitrogen doping and nitrogen-oxygen codoping through K2CO3 activation. Results showed that these samples exhibited a high specific surface area of 1209-2307 m2/g with a pore volume of 0.492-0.868 cm3/g and a nitrogen content of 0.41-3.3 wt %. The optimized sample CNNK-1 exhibited a high adsorption capacity of 1.30 and 0.27 mmol/g in the simulated flue gas (14.4 vol % CO2 + 85.6 vol % N2) and a high CO2/N2 selectivity of 80 and 20 at 25 and 100 °C and 1 bar, respectively. Studies revealed that too many microporous pores could hinder CO2 diffusion and adsorption due to the decrease of CO2 partial pressure and thermodynamic driving force in the simulated flue gas. The CO2 adsorption of the samples was mainly chemical adsorption at 100 °C, which depended on the surface nitrogen functional groups. Nitrogen functional groups (pyridinic-N and primary and secondary amines) reacted chemically with CO2 to produce graphitic-N, pyrrolic-like structures, and carboxyl functional groups (-N-COOH). Nitrogen and oxygen codoping increased the amount of nitrogen doping content in the sample, but acidic oxygen functional groups (carboxyl groups, lactones, and phenols) were introduced, which weakened the acid-base interactions between the sample and CO2 molecules. It was demonstrated that SO2 and water vapor had inhibition effects on CO2 adsorption, while NO nearly has no effect on the complex flue gas. Cyclic regenerative adsorption showed that CNNK-1 possessed excellent regeneration and stabilization ability in complex flue gases, indicating that corncob-derived biocarbon had excellent CO2 adsorption in high-temperature flue gas.

4.
Mol Med ; 28(1): 11, 2022 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093024

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common type of neurodegenerative disease in the contemporary era, and it is still clinically incurable. Eriodictyol, a natural flavonoid compound that is mainly present in citrus fruits and some Chinese herbal medicines, has been reported to exert anti-inflammatory, antioxidant, anticancer and neuroprotective effects. However, few studies have examined the anti-AD effect and molecular mechanism of eriodictyol. METHODS: APP/PS1 mice were treated with eriodictyol and the cognitive function of mice was assessed using behavioral tests. The level of amyloid-ß (Aß) aggregation and hyperphosphorylation of Tau in the mouse brain were detected by preforming a histological analysis and Western blotting. HT-22 cells induced by amyloid-ß peptide (1-42) (Aß1-42) oligomers were treated with eriodictyol, after which cell viability was determined and the production of p-Tau was tested using Western blotting. Then, the characteristics of ferroptosis, including iron aggregation, lipid peroxidation and the expression of glutathione peroxidase type 4 (GPX4), were determined both in vivo and in vitro using Fe straining, Western blotting and qPCR assays. Additionally, the expression level of vitamin D receptor (VDR) and the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway were tested using Western blotting and qPCR assays. Afterward, HT-22 cells with VDR knockout were used to explore the potential mechanisms, and the relationship between VDR and Nrf2 was further assessed by performing a coimmunoprecipitation assay and bioinformatics analysis. RESULTS: Eriodictyol obviously ameliorated cognitive deficits in APP/PS1 mice, and suppressed Aß aggregation and Tau phosphorylation in the brains of APP/PS1 mice. Moreover, eriodictyol inhibited Tau hyperphosphorylation and neurotoxicity in HT-22 cells induced by Aß1-42 oligomer. Furthermore, eriodictyol exerted an antiferroptosis effect both in vivo and in vitro, and its mechanism may be associated with the activation of the Nrf2/HO-1 signaling pathway. Additionally, further experiments explained that the activation of Nrf2/HO-1 signaling pathway by eriodictyol treatment mediated by VDR. CONCLUSIONS: Eriodictyol alleviated memory impairment and AD-like pathological changes by activating the Nrf2/HO-1 signaling pathway through a mechanism mediated by VDR, which provides a new possibility for the treatment of AD.


Assuntos
Ferroptose/efeitos dos fármacos , Flavanonas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Receptores de Calcitriol/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Biomarcadores , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Flavanonas/química , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Fosforilação , Agregação Patológica de Proteínas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteínas tau/metabolismo
5.
Bull Environ Contam Toxicol ; 105(6): 899-905, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33216155

RESUMO

The aim of the current study was to track the composition, spatial and temporal distribution charactistics of triazine herbicides in arable soils and corns in typical agricultural regions of Liaoning Province, China. All samples were analyzed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Twelve kinds of triazine herbicides were found including atrazine, simazine, prometryn, propazine, ametryn, metribuzin, simetryn, aziprotryne, cyanizine, atrazine-desethyl, atrazine-desisopropyl and atrazine-desethyl-desisopropyl in the soil samples, of which atrazine, simazine, prometryn, atrazine-desethyl and atrazine-desethyl-desisopropyl were proved to be the predominant species with a high incidence though relatively low contamination level. The maximum concentration of atrazine in the soils was 73.80 µg·kg-1. Five kinds of triazine herbicides were found in corns in the region including atrazine, simazine, prometryn, atrazine-desethyl and atrazine-desethyl-desisopropyl with the detection rate 96.4%, 17.8%, 14.3%, 60.7% and 46.4%, respectively. The maximum contaminant level of atrazine in corns was 12.52 µg·kg-1, which is lower than that regulated in the National Standard of the People's Republic of China (GB2763-2012).


Assuntos
Herbicidas/análise , Triazinas/análise , Atrazina/análise , China , Cromatografia Líquida de Alta Pressão/métodos , Simazina , Solo , Espectrometria de Massas em Tandem/métodos
6.
Bioorg Chem ; 83: 1-5, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30339860

RESUMO

Two new monoterpene indole alkaloids, naucleaoffines A (1) and B (2), together with six known alkaloids (3-8), were isolated from the stems and leaves of Nauclea officinalis. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with the data reported in literature. All isolated compounds were evaluated for their anti-inflammatory activities and anti-HIV-1 activities. Compounds 1-8 exhibited significant inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro with IC50 values comparable to that of hydrocortisone. In addition, compounds 1-8 showed significant anti-HIV-1 activities with EC50 ranged from 0.06 to 2.08 µM. These findings suggest that the discoveries of these indole alkaloids with significant anti-inflammatory activities and anti-HIV-1 activities isolated from N. officinalis could be of great importance to the development of new anti-inflammatory and anti-HIV agents.


Assuntos
Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Alcaloides Indólicos/farmacologia , Monoterpenos/farmacologia , Rubiaceae/química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Relação Dose-Resposta a Droga , HIV-1/efeitos dos fármacos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/química , Monoterpenos/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Relação Estrutura-Atividade
7.
J Environ Manage ; 243: 308-317, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31102898

RESUMO

Ball-milled biochar has recently attracted a lot of attention due to the simplicity of its preparation and low cost. However, it is unknown if the biochar is environmentally safe. Here, the toxic effect of ball-milled biochar on Streptomyces was compared to that of pristine biochar and two other carbon nanomaterials of different shapes-graphene oxide and multi-walled carbon nanotubes. The effect of these different materials on antibiotic production was characterized. The results showed that even at concentrations of up to 10 mg/L, pristine biochar had a negligible effect on toxicity and antibiotic production in Streptomyces. However, after ball milling, the physical and chemical properties of biochar changed dramatically. Cells were severely damaged, and there was a significant increase in antibiotic production after the addition of ball-milled biochar. Exposure to 10 mg/L of ball-milled biochar caused massive cell disruption; the survival rate of Streptomyces coelicolor M145 cells was only 68.2% as compared to 90% after treatment with 10 mg/L graphene oxide and multi-walled carbon nanotubes. The secretion of the antibiotics- the red intracellular pigment undecylprodigiosin (RED) and blue diffusible pigment actinorhodin (ACT) was enhanced with the highest level in treatment with ball milled biochar, as compared to that with the other two carbon nanomaterials. This effect can be attributed to increased expression of pathway-specific regulatory genes redD, redZ and actⅡ-ORF4. Ball-milled biochar can be developed as an effective additive to increase antibiotic yield. However, we should restrict the large-scale use of ball-milled biochar before fully understanding its impact on the environment and human health.


Assuntos
Grafite , Nanotubos de Carbono , Streptomyces , Carvão Vegetal , Óxidos , Respeito
8.
Water Sci Technol ; 79(9): 1705-1716, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31241476

RESUMO

Biochars produced from different feedstocks via pyrolytic carbonization and ultraviolet (UV) modification were used as alternative adsorbents for aqueous hexavalent chromium (Cr(VI)) remediation. Structural and morphological analysis showed that UV irradiation increased the surface area of biochar and added a large amount of oxygen-containing functional groups on the biochar's surface, resulting in about 2-5 times increase of Cr(VI) removing capacity (14.39-20.04 mg/g) compared to that of unmodified biochars (3.60-8.43 mg/g). The sorption ability among different feedstocks after modification was as follows: corn stack > sawdust > wheat straw. The adsorption kinetics and adsorption isotherm data agreed well with the pseudo-second-order model and Freundlich model, respectively. Experimental and modeling results suggested that the oxygen-containing functional groups and surface areas of biochars were notably increased after UV irradiation, which was mainly governed by surface complexation. X-ray photoelectron spectroscopy analysis showed that reduction occurred during Cr(VI) adsorption. In addition, UV irradiation significantly increased the concentration of dissolved organic matter (DOM) in biochars. The collected outcomes showed that UV-modified biochar was a good material for the removal of hexavalent chromium from aqueous medium. The excellent adsorption capacity, environmental-friendly and low cost properties made the novel material an auspicious candidate for environmental remediation.


Assuntos
Cromo/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Carvão Vegetal , Água
9.
J Environ Sci (China) ; 85: 107-118, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471017

RESUMO

Biochar (BC) and rhamnolipid (RL) is used in bioremediation of petroleum hydrocarbons, however, the combined effect of BC and RL in phytoremediation has not been studied until now. In this paper, the phytoremediation of petroleum hydrocarbon-contaminated soil using novel plant Spartina anglica was enhanced by the combination of biochar (BC) and rhamnolipid (RL). Samples of petroleum-contaminated soil (10, 30 and 50 g/kg) were amended by BC, BC+ RL and rhamnolipid modified biochar (RMB), respectively. After 60 day's cultivation, the removal rate of total petroleum hydrocarbons (TPHs) for unplanted soil (UP), planted soil (P), planted soil with BC addition (P-BC), planted soil with BC and RL addition (P-BC + RL) and planted soil with addition of RMB (P-RMB) were 8.6%, 19.1%, 27.7%, 32.4% and 35.1% in soil with TPHs concentration of 30 g/kg, respectively. Compared with UP, the plantation of Spartina anglica significantly decreased the concentration of C8-14 and tricyclic PAHs. Furthermore, the application of BC and RMB alleviated the toxicity of petroleum hydrocarbons to Spartina anglica via improving plant growth with increasing plant height, root vitality and total chlorophyll content. High-throughput sequencing result indicated that rhizosphere microbial community of Spartina anglica was regulated by the application of BC and RMB, with increase of bacteria and plant mycorrhizal symbiotic fungus in biochar and RMB amended soil.


Assuntos
Biodegradação Ambiental , Petróleo/análise , Poaceae/fisiologia , Poluentes do Solo/análise , Carvão Vegetal/química , Glicolipídeos/química , Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos , Rizosfera , Microbiologia do Solo , Poluentes do Solo/metabolismo
10.
J Environ Sci (China) ; 81: 80-92, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30975332

RESUMO

A column microcosm was conducted by amending crude oil into Dagang Oilfield soil to simulate the bioremediation process. The dynamic change of microbial communities and metabolic genes in vertical depth soil from 0 to 80 cm were characterized to evaluate the petroleum degradation potential of indigenous microorganism. The influence of environmental variables on the microbial responds to petroleum contamination were analyzed. Degradation extent of 42.45% of n-alkanes (C8-C40) and 34.61% of 16ΣPAH were reached after 22 weeks. Relative abundance of alkB, nah, and phe gene showed about 10-fold increment in different depth of soil layers. Result of HTS profiles demonstrated that Pseudomonas, Marinobacter and Lactococcus were the major petroleum-degrading bacteria in 0-30 and 30-60 cm depth of soils. Fusarium and Aspergillus were the dominant oil-degrading fungi in the 0-60 cm depth of soils. In 60-80 cm deep soil, anaerobic bacteria such as Bacteroidetes, Lactococcus, and Alcanivorax played important roles in petroleum degradation. Redundancy analysis (RDA) and correlation analysis demonstrated that petroleum hydrocarbons (PHs) as well as soil salinity, clay content, and anaerobic conditions were the dominant effect factors on microbial community compositions in 0-30, 30-60, and 60-80 cm depth of soils, respectively.


Assuntos
Biodegradação Ambiental , Petróleo/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Genes Microbianos , Hidrocarbonetos , Microbiota , Campos de Petróleo e Gás , Petróleo/análise , Poluição por Petróleo , Salinidade , Poluentes do Solo/análise
11.
Breed Sci ; 67(5): 535-539, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29398948

RESUMO

The fertility conversion of photoperiod thermo-sensitive genic male sterility (P/TGMS) lines in rice is mostly regulated by the P/TGMS genes in different environmental conditions. A point mutation with G-C on the pms3 (p/tms12-1) gene regulates the pollen fertility of Nongken58S and a large amount of Nongken58S-derived lines. In this study, we developed and designed a functional co-dominant marker according to the SNP loci for the pms3 (p/tms12-1) gene. We can differentiate the SNP loci in pms3 (p/tms12-1) gene from another TGMS lines and inbred cultivars using the dpms3-54 marker. The results showed that 376 bp band was detected in the homozygous genotype for pms3 (p/tms12-1), while 359 bp band was detected in the homozygous genotype for non-pms3 (p/tms12-1), two bands with 376 and 359 bp were detected in the heterozygous genotype. The dpms3-54 marker can be used to test the purity of two-line hybrid rice seeds and to divide each of F1 plant into homozygous and heterozygous genotypes at the seedling stage. Thus, this study provide a useful functional marker to detect pms3 (p/tms12-1) gene in different genetic resources and populations, which can be applied to the development and breeding of P/TGMS lines in two-line hybrid rice system with marker-assisted selection.

12.
Theor Appl Genet ; 127(5): 1173-82, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24619164

RESUMO

KEY MESSAGE: Fine mapping of the novel thermo-sensitive genic male sterility locus tms9 - 1 in the traditional TGMS line HengnongS-1 revealed that the MALE STERILITY1 homolog OsMS1 is the candidate gene. Photoperiod-thermo-sensitive genic male sterility (P/TGMS) has been widely used in the two-line hybrid rice breeding system. HengnongS-1 is one of the oldest TGMS lines and is often used in indica two-line breeding programs in China. In this study, our genetic analysis showed that the TGMS gene in HengnongS-1 was controlled by a single recessive gene that was non-allelic with the other TGMS loci identified, including C815S, Zhu1S and Y58S. Using SSR markers and bulked segregant analysis, we located the TGMS locus on chromosome 9 and named the gene tms9-1. Fine mapping further narrowed the tms9-1 loci to a 162 kb interval between two dCAPS markers. Sequence analysis revealed that a T to C substitution results in an amino acid change in the tms9-1 candidate gene (Os09g27620) in HengnongS-1 as compared to Minghui63. Sequencing of other rice accessions, including six P/TGMS lines, seven indica varieties and nine japonica varieties, showed that this SNP was exclusive to HengnongS-1. With multiple sequence alignment and expression pattern analyses, the rice MALE STERILITY1 homolog OsMS1 gene was identified as the candidate gene for tms9-1. Therefore, our study identified a novel TGMS locus and will facilitate the functional identification of the tms9-1 gene. Moreover, the markers linked to the tms9-1 gene will provide useful tools for the development of new TGMS lines by marker-assisted selection in two-line hybrid rice breeding programs.


Assuntos
Genes de Plantas , Oryza/genética , Infertilidade das Plantas/genética , Temperatura , Mapeamento Cromossômico , Estudos de Associação Genética , Hibridização Genética , Oryza/anatomia & histologia , Oryza/fisiologia
13.
Sci Total Environ ; 912: 168972, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38043822

RESUMO

The response of the microbes to total petroleum hydrocarbons (TPHs) in three types of oilfield soils was researched using metagenomic analysis. The ranges of TPH concentrations in the grassland, abandoned well, working well soils were 1.16 × 102-3.50 × 102 mg/kg, 1.14 × 103-1.62 × 104 mg/kg, and 5.57 × 103-3.33 × 104 mg/kg, respectively. The highest concentration of n-alkanes and 16 PAHs were found in the working well soil of Shengli (SL) oilfield compared with those in Nanyang (NY) and Yanchang (YC) oilfields. The abandoned well soils showed a greater extent of petroleum biodegradation than the grassland and working well soils. Α-diversity indexes based on metagenomic taxonomy showed higher microbial diversity in grassland soils, whereas petroleum-degrading microbes Actinobacteria and Proteobacteria were more abundant in working and abandoned well soils. RDA demonstrated that low moisture content (MOI) in YC oilfield inhibited the accumulation of the petroleum-degrading microbes. Synergistic networks of functional genes and Spearman's correlation analysis showed that heavy petroleum contamination (over 2.10 × 104 mg/kg) negatively correlated with the abundance of the nitrogen fixation genes nifHK, however, in grassland soils, low petroleum content facilitated the accumulation of nitrogen fixation genes. A positive correlation was observed between the abundance of petroleum-degrading genes and denitrification genes (bphAa vs. nirD, todC vs. nirS, and nahB vs. nosZ), whereas a negative correlation was observed between alkB (alkane- degrading genes) and amo (ammonia oxidation), hao (nitrification). The ecotoxicity of petroleum contamination, coupled with petroleum hydrocarbons (PH) degradation competing with nitrifiers for ammonia inhibited ammonia oxidation and nitrification, whereas PH metabolism promoted the denitrification process. Moreover, positive correlations were observed between the abundance of amo gene and MOI, as well as between the abundance of the dissimilatory nitrate reduction gene nirA and clay content. Thus, improving the soil physicochemical properties is a promising approach for decreasing nitrogen loss and alleviating petroleum contamination in oilfield soils.


Assuntos
Petróleo , Poluentes do Solo , Petróleo/análise , Campos de Petróleo e Gás , Solo/química , Amônia/análise , Biodegradação Ambiental , Hidrocarbonetos/análise , Alcanos , Microbiologia do Solo , Poluentes do Solo/análise
14.
Sci Total Environ ; 945: 173864, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879032

RESUMO

Cyanobacteria blooms (CBs) caused by eutrophication pose a global concern, especially Microcystis aeruginosa (M. aeruginosa), which could release harmful microcystins (MCs). The impact of microplastics (MPs) on allelopathy in freshwater environments is not well understood. This study examined the joint effect of adding polystyrene (PS-MPs) as representative MPs and two concentrations (2 and 8 mg/L) of pyrogallol (PYR) on the allelopathy of M. aeruginosa. The results showed that the addition of PS-MPs intensified the inhibitory effect of 8 mg/L PYR on the growth and photosynthesis of M. aeruginosa. After a 7-day incubation period, the cell density decreased to 69.7 %, and the chl-a content decreased to 48 % compared to the condition without PS-MPs (p < 0.05). Although the growth and photosynthesis of toxic Microcystis decreased with the addition of PS-MPs, the addition of PS-MPs significantly resulted in a 3.49-fold increase in intracellular MCs and a 1.10-fold increase in extracellular MCs (p < 0.05). Additionally, the emission rates of greenhouse gases (GHGs) (carbon dioxide, nitrous oxide and methane) increased by 2.66, 2.23 and 2.17-fold, respectively (p < 0.05). In addition, transcriptomic analysis showed that the addition of PS-MPs led to the dysregulation of gene expression related to DNA synthesis, membrane function, enzyme activity, stimulus detection, MCs release and GHGs emissions in M. aeruginosa. PYR and PS-MPs triggered ROS-induced membrane damage and disrupted photosynthesis in algae, leading to increased MCs and GHG emissions. PS-MPs accumulation exacerbated this issue by impeding light absorption and membrane function, further heightening the release of MCs and GHGs emissions. Therefore, PS-MPs exhibited a synergistic effect with PYR in inhibiting the growth and photosynthesis of M. aeruginosa, resulting in additional risks such as MCs release and GHGs emissions. These results provide valuable insights for the ecological risk assessment and control of algae bloom in freshwater ecosystems.


Assuntos
Gases de Efeito Estufa , Microcistinas , Microcystis , Microplásticos , Pirogalol , Microcystis/fisiologia , Microcystis/efeitos dos fármacos , Microcistinas/toxicidade , Microplásticos/toxicidade , Alelopatia , Poluentes Químicos da Água/toxicidade , Fotossíntese/efeitos dos fármacos
15.
Aging (Albany NY) ; 16(9): 7979-7999, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38742934

RESUMO

BACKGROUND: Xiaochaihu (XCH) decoction is a traditional Chinese prescription that has been recorded in the pharmacopeia of the People's Republic of China. In China, the XCH decoction is used clinically to treat a variety of tumors, including breast cancer. However, its potential mechanism of action is still undefined. METHODS: The chemical compounds in the XCH decoction were identified via Q Exactive Orbitrap LC-MS/MS. Then, we screened the active ingredients and targets in the XCH decoction from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Next, Cytoscape and Metascape were used to construct an active ingredient-target-disease network, which included a protein-protein interaction (PPI) network, GO enrichment analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Finally, we used molecular docking and in vitro experiments to verify the results of network pharmacology analysis. RESULTS: More than 70 major compounds were identified by Q Exactive Orbitrap LC-MS/MS analysis from the XCH decoction. A total of 162 active ingredients and 153 targets related to the XCH decoction and breast cancer were identified, and a compound-target-disease network was constructed. GO and KEGG analyses revealed that the XCH decoction regulated the drug response, apoptosis process, cancer pathway, and PI3K/Akt signaling pathway. Molecular docking and experimental validation indicated that the XCH decoction suppressed proliferation and induced apoptosis in breast cancer cells by regulating the expression of apoptosis-related proteins and inhibiting the PI3K/Akt pathway. CONCLUSIONS: This study suggested that the XCH decoction can be used to treat breast cancer by inhibiting cell proliferation, inducing apoptosis and downregulating the PI3K/Akt signaling pathway.


Assuntos
Neoplasias da Mama , Medicamentos de Ervas Chinesas , Farmacologia em Rede , Mapas de Interação de Proteínas , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Simulação de Acoplamento Molecular , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Espectrometria de Massas em Tandem , Células MCF-7 , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose/efeitos dos fármacos , Medicina Tradicional Chinesa
16.
Mol Nutr Food Res ; 68(10): e2300737, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38700077

RESUMO

SCOPE: Yogurt consumption is related to a decreased risk of colorectal cancer (CRC), but whether such association is causal remains unclear. Patients with familial adenomatous polyposis (FAP) are at increased risk of CRC development. Here, the study investigates the efficacy of yogurt for intestinal polyposis chemoprevention in ApcMin/+ mice, a preclinical model for human FAP. METHODS AND RESULTS: A 10-week yogurt supplementation (15 g kg-1) in ApcMin/+ mice significantly reduces the intestinal polyp number (6.50 ± 0.97 versus 1.80 ± 0.49; p < 0.001) compared to controls. 16S rRNA gene-based microbiota analysis suggests that yogurt supplementation may greatly modulate the gut microbiome composition, especially in the relative abundance of Lactobacillus and Bifidobacterium. Importantly, the fecal concentration of d-lactate (d-Lac, 0.39 ± 0.04 µmol g-1 versus 8.14 ± 0.62 µmol g-1; p < 0.001) is boosted by yogurt, while oral administration with d-Lac (125 or 250 mg kg-1) reduces the polyp number by 71.43% or 77.14% (p < 0.001), respectively. The study also observes that d-Lac does not affect cell viability and anchorage-independence in CRC cells, but it greatly suppresses epidermal growth factor (EGF) or 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell transformation in preneoplastic cells. Mechanistically, it demonstrates that d-Lac may attenuate epithelial cell transformation by targeting PI3K/AKT/ß-catenin axis. CONCLUSION: Yogurt protects against intestinal polyposis in ApcMin/+ mice, and d-Lac may partially account for the chemopreventive effects above.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Iogurte , Animais , Neoplasias Colorretais/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/prevenção & controle , Humanos , Camundongos Endogâmicos C57BL , Camundongos , Masculino , Ácido Láctico , Carcinogênese/efeitos dos fármacos , Fezes/microbiologia , Fezes/química , Proteína da Polipose Adenomatosa do Colo/genética
17.
ACS Appl Mater Interfaces ; 16(17): 21782-21789, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38635211

RESUMO

Improving the efficiency of platinum group metals (Pt, Pd, Rh, etc.) in catalytic oxidation reactions remains an urgent topic. The conflict between the low-temperature activity and high-temperature stability of noble metals can hardly reach a consensus. For instance, Pt cluster catalysts supported on CeO2 with high low-temperature activity will suffer from deactivation due to the redispersion under high-temperature lean-burn reaction conditions. Herein, two Pt1/CeO2 prepared by the incipient wetness impregnation method using different Pt precursors possessed varied Pt-O and Pt-O-Ce coordination numbers (CNs). They showed various priorities in CO oxidation versus NH3 selective catalytic oxidation, materials with higher CNPt-O-Ce selectively catalyzing NH3 oxidation to N2 more superior, conversely materials with lower CNPt-O-Ce performing better in CO oxidation. After activation by H2 reduction, both formed massive Pt clusters on the CeO2 surface but showed drastically distinct stability in lean-burn CO oxidation reactions. By summarizing the experimental results of high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, Raman spectroscopy, in situ diffuse reflectance infrared Fourier transform spectroscopy, etc., it is beyond doubt that the difference in the initial states of Pt1 due to distinct precursors indeed determine the redispersion behavior of the reduced Pt clusters on CeO2. Materials with lower CNPt-O-Ce and higher CNPt-O are more likely to form robust Pt clusters, as they are not conducive to Pt anchoring, thus restricting the reversible structural evolution occurring under lean-burn CO oxidation and reductive conditions. This approach serves as a guide for the convenient and efficient construction and exploration of robust Pt cluster catalysts.

18.
Heliyon ; 10(9): e30676, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774085

RESUMO

Through numerical simulation, this study investigates the flow field characteristics of the variable diameter stabilizer in drilling tools under various conditions. It analyzes the influence of different flow rates and speeds on axial velocity and pressure distribution. The results indicate that more significant flow rates correspond to higher average axial velocities across sections, facilitating the transport of drilling fluid and cuttings. Increasing rotational speed leads to greater pressure differences between adjacent sections, consequently elevating the overall pressure drop of the tool, which, to some extent, aids in transporting drilling fluid with cuttings. During rotation, the vortex zone on the backside of the stabilizer creates a hovering and accumulation of cuttings, causing mud agglomeration, thereby affecting tool performance. During structural optimization of the tool, priority should be given to a transitional design of the outlet area in the functional core zone, aiming to alleviate the impact of abrupt structural expansions on cuttings transport.

19.
Chemosphere ; 340: 139801, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37574086

RESUMO

Combination of microbial fuel cell (MFC) and advanced oxidation process (AOP) is promising for pollutant removal. In this paper, Cu0-loaded carbon cloth cathode by electrodeposition (Cu@CC-PS-MFC) was applied to enhance 2,4-dichlorophenol (2,4-DCP) degradation based on persulfate (PS) activation in microbial fuel cell. Cu0 exhibited a typical structure of face-centered cubic metal polyhedron on carbon cloth. The removal of 2,4-DCP by Cu@CC-PS-MFC (75.6%) was enhanced by more than 50% compared to CC-PS-MFC (49.2%) after 1 h of reaction. 30 mg/L 2,4-DCP in Cu@CC-PS-MFC was completely removed and achieved a high mineralization (80.6%) after 9 h of reaction under optimized condition with low dissolved copper ion concentration (0.615 mg/L). Meanwhile, more than 90% removal of 2,4-DCP was stably achieved with flow operation condition (hydraulic residence time of 7.2 h). The change of copper valent state Cu0/Cu2O/CuO was the main mechanism of PS activation with main reactive species of O•H and O21. The bioanode of MFC enhanced the in-situ regeneration of ≡Cu+ and ≡Cu0 on the catalyst surface by transporting electrons, which was believed to contribute to good catalyst lifetime and excellent 2,4-DCP removal. Electrodeposited copper contributes to the enhanced degradation of 2,4-DCP with energy recovery at the same time which can further broaden the application MFC.


Assuntos
Fontes de Energia Bioelétrica , Clorofenóis , Cobre/química , Oxirredução
20.
Sci Total Environ ; 856(Pt 2): 159186, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36202351

RESUMO

The reduction process of pollutants by nano zero-valent iron (nZVI) is limited by mass transfer and its effective utilization, and previous studies have ignored the electron loss caused by its oxidative passivation. The carbon-coated structure can effectively inhibit the oxidation of nZVI, but the effectiveness of carbon-coated nZVI (Fe0@C) as a reducing agent in soil remediation is unclear. Therefore, in this study, the Fe0@C/surfactant system was used to remove soil-adsorbed nitrobenzene (NB) to simultaneously enhance the mass transfer process and effective utilization of nZVI. The results showed that the use of surfactants effectively promoted the desorption of NB adsorbed by the soil, and the desorption process was affected by factors such as the type and concentration of surfactants, water-soil ratio, and soil organic matter (SOM) content. The enhanced desorption of NB by the surfactant in the soil system promoted the effective contact between the composite and NB, thereby enhancing the reduction of NB by the composite. In addition, Fe0@C exhibited excellent performance for the reduction of soil-adsorbed NB compared with the conventional nZVI, and this advantage was more obvious in the potting soil system. However, the composite will be gradually passivated due to the alkaline environment during the reduction process, and this phenomenon was especially obvious in the campus soil system. When the pH value decreased from 9 to 3, the proportion of aniline (AN) generated in the campus soil system increased from 19.37 % to 69.29 %. In addition, in potting soil systems with high SOM content, the adsorption of soil particles to the composite and the high dissolved organic matter (DOM) content resulting from the high SOM content also negatively affected the reduction process. The conclusions of this study demonstrate the great potential of the Fe0@C/surfactant system for in-situ contaminated site remediation applications.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Poluentes Químicos da Água , Ferro/química , Solo/química , Tensoativos/química , Carbono , Poluentes Químicos da Água/análise , Nitrobenzenos/química , Poluentes do Solo/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA