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1.
Chem Biodivers ; : e202400190, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860451

RESUMEN

Six low molecular weight fenugreek polysaccharides (FP) were isolated and purified by ethanol stepwise precipitation (EFP-20, EFP-40, and EFP-60) and DEAE-52 cellulose column method (DFP-0, DFP-0.15, and DFP-0.3), respectively. The effects of different separation and purification techniques on the preliminary properties and biological activities of fenugreek polysaccharides were compared. The results showed that the DEAE-52 cellulose-eluted fractions had a higher total sugar content and displayed a looser structure. The molecular weights of all six fractions were in the range of 4-19 kDa, with significant changes in the ratio of galactose to mannose. All six fractions contained α-D-galactopyranose and ß-D-mannopyranose structures. Activity tests showed that all six fractions possessed antioxidant, hypoglycemic and DNA-protective activities. Among them, the DFP-0 fraction showed the highest activity. Overall, different isolation and purification methods lead to changes in the properties and bioactivities of FP, which provides a theoretical basis for the development and application of FP in functional foods and drugs.

2.
Chem Biodivers ; 21(2): e202301684, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38224313

RESUMEN

To develop new chemicals that are stable at high temperatures with biological activity, a pyrrole intermediate was firstly synthesized using glucosamine hydrochloride as raw materials through cyclization and oxidation. Further, two novel pyrrole ester derivatives were prepared via Steglich esterification from pyrrole intermediate with vanillin and ethyl maltol, respectively. Nuclear magnetic resonance (1 H-NMR, 13 C NMR), infrared spectroscopy (IR) and high resolution mass spectrometry (HRMS) were used to confirm the target compounds. Thermal behavior of the compounds was investigated by thermogravimetry (TG), differential scanning calorimeter (DSC) and the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) methods. The plausible pyrolytic mechanism was proposed. Additionally, their biological activities against the pathogens Fusarium graminearum, Fusarium oxysporum, Fusarium moniliforme, Phytophthora nicotianae, and Rhizoctonia solani were assessed. These target compounds showed outstanding antifungal activities and the highest inhibitor rates of 62.50 % and 68.75 % against R. solani with EC50 values of 0.0296 and 0.0200 mg mL-1 , respectively. SDHI protein sequence was molecularly docked to identify the binding mechanisms in the active pocket and examine the interactions between both the molecules and the SDHI protein.


Asunto(s)
Antifúngicos , Fusarium , Antifúngicos/química , Ésteres/farmacología , Pirroles/farmacología , Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Relación Estructura-Actividad
3.
J Environ Manage ; 352: 120124, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38244412

RESUMEN

Iron is recognized as a physiological requirement for anammox bacteria (AnAOB), with Fe(II) considered to be the most effective form. However, Fe(III), instead of Fe(II) is the common iron form in natural and artificial ecosystems. In this study, the nitrogen removal performance and metabolic mechanisms in anammox consortia with soluble and non-soluble Fe(III) as the sole iron element were investigated. After the 150-day operation, the soluble (FeCl3) and insoluble (Fe2O3) Fe(III)-fed anammox systems reached nitrogen removal rates of 71.84 ± 0.80% and 50.20 ± 0.98%, respectively. AnAOB could survive with soluble (FeCl3) or insoluble (Fe2O3) Fe(III) as the sole iron element, reaching relative abundances of 18.49% and 13.16%, respectively. The results show that the formation of anammox core consortia can enable AnAOB's survival to adverse external conditions of Fe(II) deficiency. Metagenomic and metatranscriptomic analysis reveal that Ca. Kuenenia can only uptake Fe(II) into the cell for metabolisms either independently through the extracellular electron transfer or with the cross-feeding of symbiotic microbes. This study provides insight into the utilization and metabolic mechanisms of Fe(III) in Ca. Kuenenia-dominated consortia, and deepens the understanding of anammox core consortia in the nitrogen, carbon, and iron cycling, further promoting the practical applications of anammox processes.


Asunto(s)
Cloruros , Compuestos Férricos , Hierro , Oxidación-Reducción , Oxidación Anaeróbica del Amoníaco , Ecosistema , Multiómica , Bacterias/genética , Bacterias/metabolismo , Compuestos Ferrosos , Nitrógeno/metabolismo , Reactores Biológicos/microbiología , Anaerobiosis , Aguas del Alcantarillado
4.
Environ Sci Technol ; 57(34): 12732-12740, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37590181

RESUMEN

Nonphotosynthetic microorganisms are typically unable to directly utilize light energy, but light might change the metabolic pathway of these bacteria indirectly by forming intermediates such as reactive oxygen species (ROS). This work investigated the role of light on nitrogen conversion by anaerobic ammonium oxidation (anammox) consortia. The results showed that high intensity light (>20000 lx) caused ca. 50% inhibition of anammox activity, and total ROS reached 167% at 60,000 lx. Surprisingly, 200 lx light was found to induce unexpected promotion of the nitrogen conversion rate, and ultraviolet light (<420 nm) was identified as the main contributor. Metagenomic and metatranscriptomic analyses revealed that the gene encoding cytochrome c peroxidase was highly expressed only under 200 lx light. 15N isotope tracing, gene abundance quantification, and external H2O2 addition experiments showed that photoinduced trace H2O2 triggered cytochrome c peroxidase expression to take up electrons from extracellular nonfermentative organics to synthesize NADH and ATP, thereby expediting nitrogen dissimulation of anammox consortia. External supplying reduced humic acid into a low-intensity light exposure system would result in a maximal 1.7-fold increase in the nitrogen conversion rate. These interesting findings may provide insight into the niche differentiation and widespread nature of anammox bacteria in natural ecotopes.


Asunto(s)
Oxidación Anaeróbica del Amoníaco , Citocromo-c Peroxidasa , Electrones , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno , Nitrógeno
5.
Ecotoxicol Environ Saf ; 263: 115361, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37597289

RESUMEN

Cadmium (Cd) removal from soil to reduce Cd accumulation in plants is essential for agroecology, food safety, and human health. Cd enters plants from soil and affects plant growth and development. Hydrogels can easily combine with Cd, thereby altering its bioavailability in soil. However, few studies have evaluated the effects of hydrogel on the complex phytotoxicity caused by Cd uptake in plants and the microbial community structure. Herein, a new poly (acrylic acid)-grafted starch and potassium humate composite (S/K/AA) hydrogel was added to soil to evaluate its impact on tobacco growth and the soil microenvironment. The results indicate that the addition of S/K/AA hydrogel can significantly improve the biomass, chlorophyll (Chl) content, and photosynthetic capacity of tobacco plants during Cd stress conditions, and decrease Cd concentration, probably by affecting Cd absorption through the expression of Cd absorption transporters (e.g., NRAMP5, NRAMP3, and IRT1). Moreover, the application of S/K/AA hydrogel not only reduced the accumulation of reactive oxygen species (ROS), but also reduced the antioxidant activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), suggesting that S/K/AA hydrogel alleviates Cd toxicity via a non-antioxidant pathway. Notably, we further analyzed the effectiveness of the hydrogel on microbial communities in Cd-contaminated soil and found that it increased the Cd-tolerant microbial community (Arthrobacter, Massilia, Streptomyces), enhancing the remediation ability of Cd-contaminated soil and helping tobacco plants to alleviate Cd toxicity. Overall, our study provides primary insights into how S/K/AA hydrogel affects Cd bioavailability and alleviates Cd toxicity in plants.


Asunto(s)
Arthrobacter , Cadmio , Humanos , Cadmio/toxicidad , Disponibilidad Biológica , Nicotiana , Hidrogeles
6.
J Environ Sci (China) ; 124: 117-129, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36182122

RESUMEN

In this study, a modified continuous-flow nitrifying reactor was successfully operated for rapid cultivation of micro-granules and achieving robust nitritation. Results showed that sludge granulation with mean size of ca. 100 µm was achieved within three weeks by gradually increasing settling velocity-based selection pressure from 0.48 to 0.9 m/hr. Though Nitrospira like nitrite-oxidizing bacteria (NOB) were enriched in the micro-granules with a ratio between ammonia-oxidizing bacteria (AOB) and NOB of 5.7%/6.5% on day 21, fast nitritation was achieved within one-week by gradually increasing of influent ammonium concentration (from 50 to 200 mg/L). Maintaining ammonium in-excess was the key for repressing NOB in the micro-granules. Interestingly, when the influent ammonium concentration switched back to 50 mg/L still with the residual ammonium of 15-25 mg/L, the nitrite accumulation efficiency increased from 90% to 98%. Experimental results suggested that the NOB repression was intensified by both oxygen and nitrite unavailability in the inner layers of micro-granules. Unexpectedly, continuous operation with ammonium in excess resulted in overproduction of extracellular polysaccharides and overgrowth of some bacteria (e.g., Nitrosomonas, Arenimonas, and Flavobacterium), which deteriorated the micro-granule stability and drove the micro-granules aggregation into larger ones with irregular morphology. However, efficient nitritation was stably maintained with extremely high ammonium oxidation potential (> 50 mg/g VSS/hr) and nearly complete washout of NOB was obtained. This suggested that smooth and spherical granule was not a prerequisite for achieving NOB wash-out and maintaining effective nitritation in the granular reactor. Overall, the micro-granules exhibited a great practical potential for high-rate nitritation.


Asunto(s)
Compuestos de Amonio , Nitritos , Amoníaco , Bacterias , Reactores Biológicos/microbiología , Nitrógeno , Oxidación-Reducción , Oxígeno/análisis , Aguas del Alcantarillado/microbiología
7.
Org Biomol Chem ; 20(27): 5383-5386, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35748786

RESUMEN

A palladium-catalyzed synthesis of tetrasubstituted allenes from aryl bromides and aryl diazoacetates is developed. This transformation proceeded via an aryl to alkenyl 1,4-palladium migration/carbene insertion/ß-H elimination sequence under mild reaction conditions.


Asunto(s)
Alcadienos , Paladio , Catálisis , Metano/análogos & derivados
8.
Org Biomol Chem ; 20(44): 8747-8755, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36314252

RESUMEN

A novel approach for converting N-substituted acetylpyrroles and primary alcohols into N-substituted pyrrolyl chalcones in air with the assistance of t-BuOK is reported, and several prominent flavor and bioactive molecules were obtained. The process entails oxidizing the alcohols to the corresponding aldehydes, and t-BuOK is crucial to the effective production of CC bonds by aldol condensation. Gas chromatography-mass spectrometry-olfactometry (GC-MS-O) was used to examine the odor properties of pyrrolyl chalcones, which are usually different from those of the associated acetylpyrroles and alcohols. The biological evaluation assay showed that the products (E)-3-(3-fluorophenyl)-1-(1-methyl-1H-pyrrol-2-yl)prop-2-en-1-one (3j), (E)-1-(1-ethyl-1H-pyrrol-2-yl)-3-phenylprop-2-en-1-one (4a), (E)-3-(4-bromophenyl)-1-(1-ethyl-1H-pyrrol-2-yl)prop-2-en-1-one (4e), (E)-3-(4-chlorophenyl)-1-(1-ethyl-1H-pyrrol-2-yl)prop-2-en-1-one (4f) and (E)-1-(1-ethyl-1H-pyrrol-2-yl)-3-(4-fluorophenyl)prop-2-en-1-one (4g) exhibited excellent inhibitory activity against R. solani with EC50 values from 0.0107 to 0.0134 mg mL-1. Molecular docking of 3j with SDH (succinate dehydrogenase) was performed to reveal the binding modes in the active pocket and analyze the interactions between the molecules and the SDH protein. Meanwhile, they have good thermal stability according to the results of thermogravimetry (TG) analysis.


Asunto(s)
Chalcona , Chalconas , Chalconas/química , Simulación del Acoplamiento Molecular , Odorantes , Alcoholes
9.
Environ Res ; 215(Pt 1): 114318, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36116498

RESUMEN

The feasibility of anammox-based processes for nitrogen-contained wastewater treatment has been verified with different anammox bacteria, however, the ecological niche of anammox bacteria under mainstream conditions is still elusive. In this study, six sludge samples collected from different habitats were utilized to culture anammox bacteria under mainstream conditions, and two distinct anammox genera (Ca. Kuenenia and Ca. Brocadia) with a relative abundance of 6.31% (C1) and 3.09% (C3), respectively, were identified. Notably, the microbial dynamics revealed that anammox bacteria (AMX), ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), Chloroflexi bacteria (CFX), and heterotrophic denitrification bacteria (HDB) were the core members in anammox consortia. However, Ca. Kuenenia and Ca. Brocadia occupied different ecological niches in anammox consortia. The dissolved oxygen and microbial structures of the anammox-continuous stirred tank reactor systems were the main factors to affect their niche differentiation. Meanwhile, comammox might exist in the systems and occupy the ecological niche of AOB in nitrogen cycling. The network analysis suggested that Ignavibacterium could be the associated bacteria in Ca. Kuenenia-dominated consortia, while Ca. Nitrotoga was that in the Ca. Brocadia-dominated consortia. Our findings reveal a valuable reference for the observation of distinct anammox genera under mainstream conditions, which provides theoretical guidance for the engineering application of mainstream anammox-based processes.


Asunto(s)
Compuestos de Amonio , Betaproteobacteria , Amoníaco , Oxidación Anaeróbica del Amoníaco , Bacterias , Reactores Biológicos/microbiología , Ecosistema , Nitritos , Nitrógeno , Oxidación-Reducción , Oxígeno , Aguas del Alcantarillado , Aguas Residuales
10.
J Environ Manage ; 324: 116262, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36183528

RESUMEN

The engineering applications of mainstream anaerobic ammonium oxidation (anammox) have raised increasing attention due to its energy-efficient, however, the organics-mediated microbial dynamics and mixotrophic metabolisms in anammox consortia under micro-aerobic conditions are still elusive. Here, the response of the anammox process to sodium acetate and glucose at a C/N ratio ranging from 0 to 0.5 was investigated under micro-aerobic conditions, respectively. Results showed that the additional glucose could promote the nitrogen removal efficiency (NRE) and nitrogen removal rate (NRR) of anammox processes at a low C/N ratio (0.3), representing 84.00% and 0.53 N kg·m-3·d-1. The introduced organics could regulate the diversity of the microbial community and simplify the microbial relationship in anammox consortia. Anammox could not benefit from the introduced sodium acetate, while glucose could effectively enhance the anammox activity and microbial interactions in anammox consortia. Glucose might also stimulate the mixotrophic mechanism of Ca. Kuenenia, further promotes the proliferation of anammox sludge under micro-aerobic conditions. This study reveals that glucose could positively mediate microbial interactions and mixotrophic metabolism in anammox consortia under micro-aerobic conditions, which raises a new horizon for the proliferation of anammox sludge for mainstream engineering applications.


Asunto(s)
Compuestos de Amonio , Aguas del Alcantarillado , Compuestos de Amonio/metabolismo , Reactores Biológicos , Acetato de Sodio , Oxidación-Reducción , Nitrógeno/metabolismo , Anaerobiosis , Glucosa , Desnitrificación
11.
J Ment Health ; 31(4): 585-596, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35786138

RESUMEN

BACKGROUND: Many workers experienced income reduction during the coronavirus disease 2019 (COVID-19) pandemic, which may link to adverse mental health. AIMS: This study aimed to examine the association of current income and reduction in income during COVID-19 with anxiety and depression levels among non-healthcare workers. METHODS: This is a multi-city cross-sectional study. We used standardized questionnaires to collect information. We regrouped the current income and income reduction during COVID-19 according to the tertile and median value of each specific city. Depression, Anxiety and Stress Scales-21 item short version (DASS-21) was used to assess anxiety and depression levels. We performed multinomial logistic regression to examine the association of current and reduced income with anxiety and depression. Path models were developed to outline the potential modification/indirect effect of subsidies from government. RESULTS: Large income reduction and low current income were significantly associated with more anxiety/depression symptoms. Path analysis showed that government subsidies could not significantly alleviate the impact of reduced income on anxiety/depression. CONCLUSION: Our findings showed that large income reduction and low current income were independently associated with anxiety/depression, while these symptoms may not be ameliorated by one-off government funds. This study suggests the need for long-term policies (e.g. developing sustained economic growth policies) to mitigate negative impacts of the COVID-19.


Asunto(s)
COVID-19 , Pandemias , Ansiedad/epidemiología , Ansiedad/psicología , COVID-19/epidemiología , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Personal de Salud/psicología , Humanos , SARS-CoV-2
12.
Anal Bioanal Chem ; 413(6): 1541-1547, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32705288

RESUMEN

In the article, a simple and label-free strategy was proposed for the sensitive detection of lysozyme based on the fluorescence quenching of positively charged gold nanorods ((+)AuNRs) to DNA-templated silver nanoclusters (DNA/AgNCs). To construct the sensor, a DNA template was designed with a C-rich sequence at the 5'-terminal for the synthesis of AgNCs, while a lysozyme binding aptamer (LBA) at the 3'-terminal for the recognition of lysozyme, and such DNA/AgNCs was used as the fluorescence probe. Meantime, the fluorescence signal of such DNA/AgNCs can be quenched based on the electrostatic adsorption of them with (+)AuNRs, due to the surface energy transfer. In the presence of lysozyme, the specific binding happened between the LBA section of DNA/AgNCs and lysozyme, inducing the reduction of the total charge of DNA/AgNCs and weakening the adsorption of them with (+)AuNRs, which directly resulting in the recovery of the fluorescence signal. Besides, the fluorescence signal recovery of DNA/AgNCs has a linear positive proportional relationship with lysozyme concentration in the range of 10 pM-2.0 nM under the optimal conditions. Moreover, a satisfactory recovery (99.6-107.2%) was obtained while detecting lysozyme in human serum samples. Graphical abstract A simple and label-free strategy was proposed for the sensitive detection of lysozyme based on the fluorescence quenching of positively charged gold nanorods ((+)AuNRs) to DNA-templated silver nanoclusters (DNA/AgNCs).


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Muramidasa/análisis , Muramidasa/sangre , Muramidasa/química , Nanotubos/química , Adsorción , Técnicas Biosensibles/métodos , Técnicas de Química Analítica , Colorantes Fluorescentes , Humanos , Límite de Detección , Modelos Lineales , Nanotecnología/métodos , Reproducibilidad de los Resultados , Albúmina Sérica Bovina/química , Espectrometría de Fluorescencia/métodos
13.
Environ Res ; 192: 110273, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33002505

RESUMEN

Pot experiments were conducted to investigate the influence of biochar addition and the mechanisms that alleviate Cd stress in the growth of tobacco plant. Cadmium showed an inhibitory effect on tobacco growth at different post-transplantation times, and this increased with the increase in soil Cd concentration. The growth index decreased by more than 10%, and the photosynthetic pigment and photosynthetic characteristics of the tobacco leaf were significantly reduced, and the antioxidant enzyme activity was enhanced. Application of biochar effectively alleviated the inhibitory effect of Cd on tobacco growth, and the alleviation effect of treatments is more significant to the plants with a higher Cd concentration. The contents of chlorophyll a, chlorophyll b, and carotenoids in the leaves of tobacco plants treated with biochar increased by 9.99%, 12.58%, and 10.32%, respectively, after 60 days of transplantation. The photosynthetic characteristics index of the net photosynthetic rate increased by 11.48%, stomatal conductance increased by 11.44%, and intercellular carbon dioxide concentration decreased to 0.92. Based on the treatments, during the growth period, the antioxidant enzyme activities of tobacco leaves comprising catalase, peroxidase, superoxide dismutase, and malondialdehyde increased by 7.62%, 10.41%, 10.58%, and 12.57%, respectively, after the application of biochar. Our results show that biochar containing functional groups can effectively reduce the effect of Cd stress by intensifying the adsorption or passivation of Cd in the soil, thereby, significantly reducing the Cd content in plant leaves, and providing a theoretical basis and method to alleviate soil Cd pollution and effect soil remediation.


Asunto(s)
Cadmio , Contaminantes del Suelo , Cadmio/análisis , Cadmio/toxicidad , Carbón Orgánico , Clorofila A , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Nicotiana
14.
Biotechnol Lett ; 43(3): 655-666, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33174145

RESUMEN

Excessive application of chemical fertilizer and continuous cropping in plastic greenhouse resulted in soil quality decline. The decrease of soil C/N ratio and the imbalance of soil carbon pool structure have brought new challenges to soil health, crop yield and sustainable agricultural development. OBJECTIVES: The experiment was set up to explore the effect of modified biochar on soil bacterial community structure, and the correlation between soil environmental factors and bacterial community structure changes. Based on the plot experiment in the field, the effect of modified biochar was studied via high-throughput MiSeq sequencing. RESULTS: Compared with the control (CK), the modified biochar (T) significantly increased soil water content, microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) content and the ratio of MBC and MBN by 7.92%, 24.58%, 2.07% and 18.95%. Diversity index analysis showed that the application of modified biochar significantly increased the Shannon index, ACE index and Chao1 index of the bacterial community by 3.05%, 5.07% and 5.24%. Compared with the control, the modified biochar decreased the relative abundance of Actinobacteriota and Chloroflex by 6.81% and 2.19%, and increased the relative abundance of Proteobacteria and Acidobacteriota by 7.34% and 12.52%. Correlation analysis shows that soil bulk density and water content may be important related factors that affect bacterial community structure. CONCLUSIONS: This study provides a theoretical basis for the directional control of modified biochar in the soil microecological environment in plastic greenhouse, which is conducive to healthy and sustainable farming.


Asunto(s)
Bacterias/efectos de los fármacos , Carbón Orgánico/farmacología , Microbiota/efectos de los fármacos , Microbiología del Suelo , Biomasa , Carbono/análisis , Carbono/metabolismo , Nitrógeno/análisis , Nitrógeno/metabolismo , Suelo/química
15.
J Environ Manage ; 293: 112906, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34087646

RESUMEN

Numerous researches have been carried out to study the effects of emerging contaminants in wastewater, such as antibiotics, nanomaterials, heavy metals, and microplastics, on the anammox process. However, they are fragmented and difficult to provide a comprehensive understanding of their effects on reactor performance and the metabolic mechanisms in anammox bacteria. Therefore, this paper overviews the effects on anammox processes by the introduced emerging contaminants in the past years to fulfill such knowledge gaps that affect our perception of the inhibitory mechanisms and limit the optimization of the anammox process. In detail, their effects on anammox processes from the aspects of reactor performance, microbial community, antibiotic resistance genes (ARGs), and functional genes related to anammox and nitrogen transformation in anammox consortia are summarized. Furthermore, the metabolic mechanisms causing the cell death of anammox bacteria, such as induction of reactive oxygen species, limitation of substrates diffusion, and membrane binding are proposed. By offering this review, the remaining research gaps are identified, and the potential metabolic mechanisms in anammox consortia are highlighted.


Asunto(s)
Reactores Biológicos , Plásticos , Anaerobiosis , Nitrógeno , Oxidación-Reducción , Aguas Residuales
16.
Appl Microbiol Biotechnol ; 104(12): 5593-5604, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32300855

RESUMEN

The salinity effect on anammox bacteria has been widely reported; however, rare studies describe the microbial dynamics of anammox-based process response to the introduction of real seawater at mainstream conditions. In this study, an anammox process at mainstream conditions without pre-enriching anammox bacteria was shifted to the feeds of a synthetic wastewater with a portion of seawater mixture. It achieved over 0.180 kg-N/(m3 day) of nitrogen removal rate with an additional seawater proportion of 20% in the influent. The bacterial biodiversity was significantly increased with the increase of seawater proportions. High relative abundance of anammox bacteria (34.24-39.92%) related to Ca. Brocadia was enriched and acclimated to the saline environment. However, the introduction of seawater caused the enrichment of nitrite-oxidizing Ca. Nitrospira, which was responsible for the deterioration of nitrogen removal efficiency. Possible adaptation metabolisms in anammox bacteria and other nitrogen transforming bacteria are discussed. These results highlight the importance of microbial diversity for anammox process under the saline environments of 20% and 40% seawater composition.


Asunto(s)
Compuestos de Amonio/metabolismo , Bacterias/metabolismo , Salinidad , Agua de Mar/microbiología , Aguas del Alcantarillado/microbiología , Anaerobiosis , Biodiversidad , Reactores Biológicos , Nitrógeno/metabolismo , Oxidación-Reducción
17.
Toxicol Appl Pharmacol ; 376: 46-57, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31125577

RESUMEN

Silica-induced pulmonary fibrosis is a kind of worldwide occupational disease, and there is no effective treatment at present. Peptide therapy has attracted significant attention due to its simple structure, high selectiveness, strong bioactivity, relative safety, and high patient tolerance. In this study, we first confirmed that M10, a 10 amino acid peptide, has anti-fibrotic effects during the early and late stages of silica-induced fibrosis in mouse models and then partly explored the underlying mechanisms in vitro. M10 was detected in both the cell cytoplasm and nuclei. M10 showed no cytotoxicity to pulmonary epithelial cells and fibroblasts at the given concentrations. Functionally, M10 can reverse the silica-induced EMT process in epithelial cells and decrease TGF-ß1-stimulated fibroblast activation. Further mechanism investigations supported that M10 can block TGF-ß1 signalling by inhibiting phosphorylation of Smad2 protein in vitro and in vivo. All of the results indicate that M10 peptide may be a new method for the treatment of silica-induced pulmonary fibrosis.


Asunto(s)
Péptidos/farmacología , Fibrosis Pulmonar/tratamiento farmacológico , Dióxido de Silicio/toxicidad , Proteína Smad2/metabolismo , Animales , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Péptidos/uso terapéutico , Fosforilación/efectos de los fármacos , Fibrosis Pulmonar/inducido químicamente , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología
18.
Environ Res ; 170: 7-15, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30554054

RESUMEN

BACKGROUND: Extensive studies have linked ambient particulate matter (PM) to an increased mortality burden from a wide range of causes. However, the effects of PM on mortality rates from specific causes were unclear. This study aimed to estimate the detrimental effects of PM on cause specific deaths in Changzhou, China. METHOD: Data representing daily mortality rates, weather conditions and particulate air pollution levels were obtained from government-controlled agencies of Changzhou, from January 1, 2015 to December 31, 2016. An inverse distance weighting method was used to assess the population exposure to PM and a time-series was performed to detect the detrimental effects of PM. RESULTS: Positive associations were identified between PMs and daily mortality rates from non-accidental, circulatory, hypertensive, respiratory and chronic lower respiratory causes at a lag of 0-3 days. The effects of PMs were strongest on hypertensive mortality, with an increase of 5.27% (95% confidence interval (CI): 2.43-8.19%) and 3.52% (95% CI: 1.55-5.53%), per 10 µg/m3 increment in PM2.5 and PM10 respectively. The elderly exhibited a higher mortality risk with PMs exposure. Females were more vulnerable to circulatory, hypertensive and respiratory death while males were more sensitive to chronic lower respiratory and neurodegenerative mortality. The effects were stronger in warm seasons for circulatory mortality and stronger in cold seasons for respiratory mortality. CONCLUSION: These findings indicate that PM could exert adverse influences on the outcomes of several pathological processes, especially for women and the elderly with hypertension disease.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Material Particulado/análisis , Anciano , Contaminación del Aire/prevención & control , Causas de Muerte , China , Femenino , Humanos , Masculino , Mortalidad
19.
Biochim Biophys Acta Mol Basis Dis ; 1864(2): 420-431, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29113749

RESUMEN

Long non-coding RNAs (lncRNAs) are important signal transduction regulators that act by various patterns. However, little is known about the molecular mechanisms of lncRNA related pathways in occupational lung fibrosis. Our previous study found that epithelial-mesenchymal transition (EMT) was one of the key events in silica-induced pulmonary fibrosis. This study showed that the lncRNA-ATB promoted EMT by acting as a miR-200c sponge. miR-200c was identified by miRNA array as a potential target of lncRNA-ATB and verified by dual luciferase reporter gene together with RNA pull-down assays. Moreover, our findings demonstrated that lncRNA-ATB is abundantly expressed during EMT of lung epithelial cells, which contributes to decreased levels of miR-200c. miR-200c targeted ZEB1 to relief silicosis by blocking EMT in vivo and in vitro. The results also suggested M2 macrophages secreted transforming growth factor-ß1 (TGF-ß1) to induce EMT process by activating lncRNA-ATB in epithelial cells. Collectively, silica-stimulated macrophages secreted TGF-ß1 to induce lncRNA-ATB in epithelia cells, promoting EMT by binding with miR-200c and releasing ZEB1. These observations provide further understanding of the regulatory network of silica-induced pulmonary fibrosis and identify new therapeutic targets hopefully.


Asunto(s)
Transición Epitelial-Mesenquimal/genética , MicroARNs/metabolismo , Fibrosis Pulmonar/patología , ARN Largo no Codificante/genética , Dióxido de Silicio/toxicidad , Células A549 , Animales , Proliferación Celular , Técnicas de Cocultivo , Células Epiteliales/metabolismo , Humanos , Pulmón/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Análisis de Secuencia por Matrices de Oligonucleótidos , Unión Proteica , Fibrosis Pulmonar/inducido químicamente , ARN Largo no Codificante/metabolismo , Transducción de Señal , Transfección , Factor de Crecimiento Transformador beta1/metabolismo , Cicatrización de Heridas , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo
20.
J Org Chem ; 83(2): 1065-1072, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29280375

RESUMEN

9,9-Disubstituted fluorenes are widely employed in materials science. We have developed a straightforward approach for the synthesis of 9,9-disubstituted fluorenes from 2-iodobiphenyls and α-diazoesters. The reaction proceeds via a tandem palladium-catalyzed C(sp2)-H activation/carbenoid insertion sequence.

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