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1.
EMBO Rep ; 25(3): 1415-1435, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38279019

RESUMEN

Eukaryotic translation initiation factors have long been recognized for their critical roles in governing the translation of coding RNAs into peptides/proteins. However, whether they harbor functional activities at the post-translational level remains poorly understood. Here, we demonstrate that eIF3f1 (eukaryotic translation initiation factor 3 subunit f1), which encodes an archetypal deubiquitinase, is essential for the antimicrobial innate immune defense of Drosophila melanogaster. Our in vitro and in vivo evidence indicate that the immunological function of eIF3f1 is dependent on the N-terminal JAMM (JAB1/MPN/Mov34 metalloenzymes) domain. Mechanistically, eIF3f1 physically associates with dTak1 (Drosophila TGF-beta activating kinase 1), a key regulator of the IMD (immune deficiency) signaling pathway, and mediates the turnover of dTak1 by specifically restricting its K48-linked ubiquitination. Collectively, these results provide compelling insight into a noncanonical molecular function of a translation initiation factor that controls the post-translational modification of a target protein.


Asunto(s)
Proteínas de Drosophila , Drosophila , Animales , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Inmunidad Innata , Factores de Iniciación de Péptidos , Transducción de Señal
2.
Ecotoxicol Environ Saf ; 284: 116934, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39182285

RESUMEN

As the negative repercussions of environmental devastation, such as air quality decline and air pollution, become more apparent, environmental consciousness is growing across the world, forcing nations to take steps to mitigate the damage. China pledged to achieve air quality improvement goal to combat global environment issue, yet the spatial-temporal differentiation and its driving factors of environment-meteorology-economic index for air quality are not fully analysed. To promote regional collaborative control of air pollution and achieve sustainable urban development, spatial and temporal different and its driving factors of air quality in Shandong Province during 2013-2020. Results revealed that concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), particulate matter 2.5 (PM2.5), particulate matter 10 (PM10), and carbon monoxide (CO-95per) exhibited decreasing trend (SO2 concentrations decreasing 84 % and CO-95per concentrations decreasing 90 %). Air quality was improved from inland areas to coastal areas. Pollutant indicators of SO2, NO2, PM10, PM2.5, and CO-95per demonstrated significant positive correlation (P < 0.05). Air temperature and precipitation are significantly negatively correlated with concentrations of SO2, NO2, PM10, PM2.5, and CO-95per but significantly positively correlated with ozone (O3-8 h). SO2, NO2, PM2.5, PM10, CO-95per, and proportion of days with heavy pollution are strongly positively correlated with proportion of secondary industry but strongly negatively correlated with proportion of tertiary industry and volume of household waste. Except for O3-8 h, pollutant index of Provincial Capital Economic Circle (PCEC) and Southern Shandong Economic Circle (SSEC) has significant negative correlation (P < 0.05) with regional gross domestic product and investment in environmental protection; however, investment in environmental protection of Eastern Shandong Economic Circle (ESEC) has no significant correlation with air pollution index. There was significant negative correlation between vegetable sowing area and SSEC pollutant index. The relationship between pollution emission and investment in environmental protection has shifted from high pollution-low investment to low pollution-low investment in PCEC, ESEC and SSEC, and the inflection point was in 2020 for PCEC, 2019 for ESEC, and 2020 for SSEC. Those results provide empirical evidence and theoretical support for the improvement of regional air quality, aiming to achieve high-quality development. According to these findings, it has been found that meteorological elements, pollutant emission, socio-economic factors and agricultural data affect air quality. Those results could provide meaningful and significant supporting for synergistic regulation of diverse pollutants.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Dióxido de Nitrógeno , Material Particulado , Análisis Espacio-Temporal , Dióxido de Azufre , China , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Dióxido de Nitrógeno/análisis , Dióxido de Azufre/análisis , Monóxido de Carbono/análisis , Ozono/análisis
3.
J Environ Manage ; 353: 120189, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38295644

RESUMEN

Insufficient carbon source has become the main limiting factor for efficient nitrogen removal in wastewater treatment. In this study, an intermittently-aerated activated sludge system with iron-chitosan (Fe-CS) beads addition was proposed for nitrogen removal from low C/N wastewater. By adding Fe-CS beads, partial nitrification-denitrification (PND) process and significant enrichment of Paracoccus (with ability of iron reduction/ammonium oxidation/aerobic denitrification) were observed in the reactor. The accumulation rate of NO2--N reached 81.9 %, and the total nitrogen removal efficiency was improved to 93.9 % by shortening the aeration time. The higher activity of ammonium oxidizing bacteria and inhibited activity of nitrite-oxidizing bacteria in Fe-CS assisted system mediated the occurrence of PND. In contrast, the traditional nitrification and denitrification process occurred in the control group. The high-throughput sequencing analysis and metagenomic results confirmed that the addition of Fe-CS induced 77.8 % and 54.9 % enrichment of Paracoccus in sludge and Fe-CS beads, respectively, while almost no enrichment was observed in control group. Furthermore, with the addition of Fe-CS beads, the expression of genes related to outer membrane porin, cytochrome c, and TCA was strengthened, thereby enhancing the electron transport of Fe(Ⅱ) (electron donor) and Fe(Ⅲ) (electron acceptor) with pollutants in the periplasm. This study provides new insights into the direct enrichment of iron-reducing bacteria and its PND performance induced by the Fe-CS bead addition. It therefore offers an appealing strategy for low C/N wastewater treatment.


Asunto(s)
Compuestos de Amonio , Quitosano , Paracoccus , Nitrificación , Aguas del Alcantarillado , Desnitrificación , Quitosano/metabolismo , Hierro , Paracoccus/metabolismo , Reactores Biológicos/microbiología , Bacterias/metabolismo , Compuestos de Amonio/metabolismo , Oxidación-Reducción , Nitrógeno/metabolismo
4.
Molecules ; 28(14)2023 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-37513173

RESUMEN

Aspirin, also known as acetylsalicylic acid, is widely consumed as a pain reliever and an anti-inflammatory as well as anti-platelet agent. Recently, our studies using the animal model of Drosophila demonstrated that the dietary supplementation of aspirin renovates age-onset intestinal dysfunction and delays organismal aging. Nevertheless, it remains probable that aspirin plays functional roles in other biological activities, for instance antiviral defense reactions. Intriguingly, we observed that the replications of several types of viruses were drastically antagonized in Drosophila macrophage-like S2 cells with the addition of aspirin. Further in vivo experimental approaches illustrate that adult flies consuming aspirin harbor higher resistances to viral infections with respect to flies without aspirin treatment. Mechanistically, aspirin positively contributes to the Drosophila antiviral defense largely through mediating the STING (stimulator of interferon genes) but not the IMD (immune deficiency) signaling pathway. Collectively, our studies uncover a novel biological function of aspirin in modulating Drosophila antiviral immunity and provide theoretical bases for exploring new antiviral treatments in clinical trials.


Asunto(s)
Drosophila , Virosis , Animales , Aspirina/farmacología , Aspirina/metabolismo , Inmunidad Innata , Antivirales/metabolismo , Suplementos Dietéticos , Drosophila melanogaster/metabolismo
5.
J Sci Food Agric ; 102(9): 3655-3664, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34882798

RESUMEN

BACKGROUND: Sodium dehydroacetate (DHA-S) is a common food additive, which can combine with serum proteins in the plasma, but the interaction mechanism between DHA-S and human serum albumin (HSA) is unclear. In this study, multiple spectroscopy techniques, isothermal titration calorimetry (ITC), molecular docking and esterase activity test were employed to investigate the interaction mechanism of DHA-S and HSA. RESULTS: A DHA-S-HSA complex was formed and the structure of HSA were altered by DHA-S. Since DHA-S changed the tight structure of the hydrophobic subdomain IIA where tryptophan (Trp) was placed, the hydrophobicity of the microenvironment of HSA was enhanced. With the addition of DHA-S, the skeleton structure of HSA became loose and the solvent shell on the HSA surface was destroyed. DHA-S altered the secondary structure of HSA, resulting in the decreased α-helix and increased ß-sheet contents. The interaction was exothermic and spontaneous driven by van der Waals and hydrogen bonding. DHA-S inhibited the esterase activity of HSA. Molecular docking demonstrated that the binding site of DHA-S on HSA located at the cavity of subdomains IIA and IIIA, but the amino acids related to esterase activity of HSA were not in the binding pocket, indicating that the mechanism by which DHA-S inhibited HSA esterase activity was the change in protein structure. CONCLUSION: This study illustrated that DHA-S interacted with HSA and the structure and function of HSA were affected by DHA-S. This research could help to understand the toxicity of DHA-S and provide basic data for safe use of food additives. © 2021 Society of Chemical Industry.


Asunto(s)
Esterasas , Albúmina Sérica Humana , Sitios de Unión , Dicroismo Circular , Esterasas/metabolismo , Humanos , Enlace de Hidrógeno , Simulación del Acoplamiento Molecular , Unión Proteica , Pironas , Albúmina Sérica Humana/química , Albúmina Sérica Humana/metabolismo , Espectrometría de Fluorescencia , Termodinámica
6.
Water Sci Technol ; 83(7): 1522-1534, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33843740

RESUMEN

During sediment remediation, adsorbent addition is an effective technology for the removal of contaminants but the cost is often high. In this study, a low-cost adsorbent, ceramsite, made from contaminated riverbed sediment was synthesized. The Fe-modified ceramsite (FMC) was used as adsorbent to remove arsenate from aqueous solutions and reduce the inorganic arsenic release from contaminated sediments. Kinetic studies showed that chemisorption mainly governed the adsorption process while batch studies yielded the theoretical adsorption capacity for arsenate of 10.63 mg/g at pH = 7 condition. Co-existing anions and pH have no significant impact on the adsorption process. In the regeneration studies, 91, 86, and 80% of the adsorption capacity were recovered in 3 cycles. In-situ remediation trials revealed that the addition of the adsorbent to sediment surface significantly reduced the release of inorganic arsenic into aqueous system, with a reduction efficiency of 86%. Furthermore, the species of the arsenic in the surface layer was significantly inactivated from an active state to a stable state. These findings highlight the application of the FMC as a facile and cost-effective adsorbent for containment of arsenic in solutions and sediments, demonstrating that they are highly applicable for practical cases.


Asunto(s)
Arsénico , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Mezclas Complejas , Concentración de Iones de Hidrógeno , Cinética
7.
Environ Monit Assess ; 192(2): 79, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31897735

RESUMEN

This study proposed a multi-criteria evaluation system for arable land resources by combining the soil integrated fertility index (IFI) with a soil cleanliness index (based on heavy metals and metalloid content). A total of 16 typical arable land units in Chongming District, China, were evaluated using the proposed evaluation system based on 104 collected soil samples in 16 towns. The comprehensive soil evaluation scores of arable lands in 16 towns were in the range of 90.7 to 99.2 with a mean of 96.2, indicating that the arable land in all 16 towns was at the level of excellent (≥ 90.0). Lower cleanliness indices had a significant impact on the final evaluation score. In comparison with single-index evaluation systems (i.e., the IFI or soil cleanliness index), the proposed multi-criteria system better reflects the quality of the soil. In the practice of arable land requisition and subsidy policy, the proposed multi-criteria evaluation system not only encourages farmers to preserve arable lands during farming but also helps agricultural authorities make effective and reliable management decisions.


Asunto(s)
Agricultura , Monitoreo del Ambiente , China , Metales Pesados/análisis , Suelo
8.
Med Sci Monit ; 23: 2065-2071, 2017 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-28456815

RESUMEN

BACKGROUND Although many attempts have been made to advance the treatment of complex anal fistula, it continues to be a difficult surgical problem. This study aimed to describe the novel technique of video-assisted anal fistula treatment (VAAFT) and our preliminary experiences using VAAFT with patients with complex anal fistula. MATERIAL AND METHODS From May 2015 to May 2016, 52 patients with complex anal fistula were treated with VAAFT at Yangpu Hospital of Tongji University School of Medicine, and the clinical data of these patients were reviewed. RESULTS VAAFT was performed successfully in all 52 patients. The median operation time was 55 minutes. Internal openings were identified in all cases. 50 cases were closed with sutures, and 2 were closed with staplers. Complications included perianal sepsis in 3 cases and bleeding in another 3 cases. Complete healing without recurrence was achieved in 44 patients (84.6%) after 9 months of follow-up. No fecal incontinence was observed. Furthermore, a significant improvement in Gastrointestinal Quality of Life Index (GIQLI) score was observed from preoperative baseline (mean, 85.5) to 3-month follow-up (mean, 105.4; p<0.001), and this increase was maintained at 9-months follow-up (mean, 109.6; p<0.001). CONCLUSIONS VAAFT is a safe and minimally invasive technique for treating complex anal fistula with preservation of anal sphincter function.


Asunto(s)
Fístula Rectal/cirugía , Cirugía Asistida por Video/métodos , Adulto , Anciano , Canal Anal/cirugía , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Calidad de Vida , Fístula Rectal/terapia , Recurrencia , Resultado del Tratamiento , Cicatrización de Heridas
9.
Med Sci Monit ; 22: 4986-4991, 2016 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-27990014

RESUMEN

BACKGROUND Systemic inflammatory response and nutritional status are important to the prognosis of patients with colorectal cancer (CRC). This study aimed to investigate the prognostic value of the combination of preoperative hemoglobin, lymphocyte, albumin, and neutrophil (HLAN) in patients with locally advanced CRC (LACRC). MATERIAL AND METHODS We performed a retrospective analysis in 536 LACRC patients undergoing radical surgery. The value of HLAN was defined as follow: HLAN=Hemoglobin (g/L)×Lymphocyte (/L)×Albumin (g/L)/Neutrophil (/L)/100. The X-tile program was used to determine the optimal cut-point of HLAN, and the prognostic value of HLAN for overall survival (OS) was evaluated with the Cox proportional hazard model. RESULTS The cut-point of HLAN was set at 19.5. Compared with the high-HLAN group, the low-HLAN group had a 1.50-fold (95% confidence interval 1.09-2.05) increased risk of death and a significantly lower OS rate (P<0.001). Furthermore, the risk stratification model based on HLAN (AUC=0.72) displayed better accuracy in OS prediction than the TNM system (AUC=0.61). CONCLUSIONS HLAN is a valuable prognostic marker for patients with LACRC.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Colorrectales/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hemoglobinas/metabolismo , Humanos , Estimación de Kaplan-Meier , Linfocitos/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias/métodos , Neutrófilos/patología , Pronóstico , Estudios Retrospectivos , Albúmina Sérica/metabolismo , Tasa de Supervivencia
10.
Bull Environ Contam Toxicol ; 95(2): 240-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26021616

RESUMEN

Polycyclic aromatic hydrocarbon (PAH) concentrations and fluxes were measured monthly in situ from rain events in an urban forest in the megapolitan city Guangzhou, China, to investigate impacts of forest canopy and soils on PAHs. Mean Σ9-PAH concentrations were 107.5, 101.6, 106.3, 107.1 and 42.4 ng L(-1) in precipitation, throughfall, seepage water at the 30 and 60 cm soil depth, and runoff, respectively, indicating a great decrease in the form of runoff. Meanwhile, annual fluxes of total PAHs decreased from precipitation (205.9 µg m(-2) year(-1)), to throughfall (156.3 µg m(-2) year(-1)), and to seepage water (65.3 µg m(-2) year(-1) at 30-cm soil depth and 7.5 µg m(-2) year(-1) at 60-cm soil depth), but increased in runoff (34.1 µg m(-2) year(-1)). When compared to precipitation, PAH fluxes decreased by 83.4% in runoff, with 29% contributed by forest canopy and 71% by soils. Soil biodegradation explained 18.2% of PAH reduction by the surface soil layer and 34.6% by the middle soil layer.


Asunto(s)
Contaminantes Atmosféricos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Lluvia/química , Contaminantes Atmosféricos/metabolismo , Biodegradación Ambiental , China , Ciudades , Bosques , Hidrocarburos Policíclicos Aromáticos/metabolismo , Microbiología del Suelo
11.
Bioresour Technol ; 394: 130178, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38072080

RESUMEN

In this study, an anaerobic/intermittently-aerated moving bed biofilm reactor (AnIA-MBBR) was proposed to realize simultaneous nitrification and endogenous denitrifying phosphorus removal (SNEDPR) in treating low carbon-to-nitrogen (C/N) ratio wastewater. The effect of different intermittent aeration modes (short and long aeration) on nutrients' removal was investigated. With the C/N ratio around 3, the removal efficiencies of total nitrogen and phosphorus were 90% and 74%, 88% and 59%, respectively, for short aeration and long aeration. The different aeration time also altered the nutrients' degradation pathway, biofilm characteristics, microbial community, and functional metabolic pathways. The results confirmed the occurrence of aerobic denitrifiers, anoxic denitrifiers, phosphorus accumulating organisms, glycogen accumulating organisms in AnIA-MBBR systems and their synergistic performance induced the SNEDPR. These results indicated that the application of AnIA in MBBR systems was an effective strategy to achieve SNEDPR, providing better simultaneous removal performance of nitrogen and phosphorus from low C/N ratio wastewater.


Asunto(s)
Nitrificación , Purificación del Agua , Aguas Residuales , Desnitrificación , Eliminación de Residuos Líquidos/métodos , Aguas del Alcantarillado , Fósforo/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Biopelículas , Anaerobiosis , Reactores Biológicos
12.
Environ Sci Pollut Res Int ; 31(39): 52171-52180, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39141263

RESUMEN

Pharmaceuticals, which are closely linked to human activities, have attracted global attention. This study investigated the occurrence characteristics of 20 pharmaceuticals in surface water of the Yangtze Estuary and adjacent sea. A total of 14 targeted pharmaceuticals were detected in both spring and summer sampling campaigns. The mean concentrations of sulfonamides and non-sulfonamides were 36.60 ± 19.43 ng·L-1 and 50.02 ± 41.07 ng·L-1, respectively. As for non-antibiotics, their concentrations were in the range of 24.34 ± 916.8 ng·L-1 with caffeine accounting for 6.17 ~ 86.70% (average percentage of 42.22%). Meanwhile, spatial distribution patterns showed similarities between antibiotics and non-antibiotics, with high levels occurring near the upper estuary, aquaculture areas, wastewater treatment plants, and the maximum turbidity zone. This phenomenon could be related to the sources of pharmaceuticals and the physicochemical properties of water bodies. Obviously, the first three areas are highly impacted by human activities or serve as important sources of terrestrial contaminants entering the East China Sea. The last area retains high amounts of suspended particles which may exert strong trapping effects on hydrophobic chemicals. Principal component analysis revealed the presence of three potential sources for pharmaceuticals in the Yangtze Estuary, with a relatively high percentage originating from incompletely treated municipal sewage. As for the temporal trend, pharmaceutical contamination was found to be higher in spring compared to summer, potentially due to variations in pharmaceutical consumption patterns, local rainfalls, and water temperatures. These findings provide fundamental data support for implementing appropriate local management strategies for pharmaceutical usages.


Asunto(s)
Monitoreo del Ambiente , Estuarios , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Preparaciones Farmacéuticas/análisis , China , Agua de Mar/química
13.
J Food Sci ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39295436

RESUMEN

The study of visualization of impact damage of fruit under different thicknesses of buffer materials can provide more efficient transportation and packaging solutions, and thus the economic losses caused by fruit damage can be reduced. Pearl cotton (EPE) is commonly used as a buffer material in the market, and the impact damage behavior of honey peaches under different thicknesses of EPE buffer material was studied by using the finite element method. Firstly, the damage area, maximum contact force and damage volume during the collision of honey peaches with EPE materials of different thicknesses (2, 4, and 6 mm) were obtained by the single pendulum device, and then the Modulus of elasticity and Poisson's ratio of peach flesh were obtained by compression test. Finally, the finite element model of honey peach was built and the collision simulations were performed. The results of the study showed that the values of mechanical parameters of honey peach decreased with the increase of the thickness of the buffer material. When the collision angle was below 60°, the honey peaches were not damaged in the collision with the EPE material with a thickness of 4 mm or more. By comparing the tested values with the simulated values, it was found that the errors of the damage area, damage volume and maximum contact force were less than 19.71%, 26.82%, and 25.88%, respectively. The study not only proves the possibility of the finite element method in the quantitative prediction of honey peaches damage but also provides rational support for the packaging design of honey peaches.

14.
Aquat Toxicol ; 259: 106535, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37086652

RESUMEN

Conventional thyroid-disrupting chemicals (TDCs) such as polybrominated diphenyl ethers, polychlorinated biphenyls, and bisphenols perturb animal's thyroid endocrine system by mimicking the action of endogenous thyroid hormones (THs), since they share a similar backbone structure of coupled benzene rings with THs. 1-methyl-3-octylimidazolium bromide ([C8mim]Br), a commonly used ionic liquid (IL), has no structural similarity to THs. Whether it interferes with thyroid function and how its mode of action differs from conventional TDCs is largely unknown. Herein, zebrafish embryo-larvae experiments (in vivo), GH3 cell line studies (in vitro), and molecular simulation analyses (in silico) were carried out to explore the effect of [C8mim]Br on thyroid homeostasis and its underlying mechanism. Molecular docking results suggested that [C8mim]+ likely bound to retinoid X receptors (RXRs), which may compromise the formation of TH receptor/RXR heterodimers. This then perturbed the negative regulation of thyroid-stimulating hormone ß (tshß) transcription by T3 in GH3 cell line. The resulting enhancement of tshß expression further caused hyperthyroidism and developmental toxicity in larval zebrafish. These findings provided a crucial aspect of the ecological risks of ILs, and presented a new insight into the thyroid-disrupting mechanisms for emerging pollutants that do not have structural similarity to THs.


Asunto(s)
Glándula Tiroides , Contaminantes Químicos del Agua , Animales , Pez Cebra/metabolismo , Simulación del Acoplamiento Molecular , Contaminantes Químicos del Agua/toxicidad , Sistema Endocrino , Hormonas Tiroideas/metabolismo , Larva
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122511, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36854229

RESUMEN

Microplastics are harmful pollutants that widely exist worldwide and pose a severe threat to all types of organisms. The effects of polystyrene microplastics (PS-MPs) on organisms have been extensively studied, but the interaction mechanism between PS-MPs and superoxide dismutase (SOD) at the molecular level has not been reported yet. Therefore, based on multiple spectroscopic methods and enzyme activity measurements, the molecular mechanism of the interaction between PS-MPs and SOD was investigated. The multispectral results showed that the protein skeleton and secondary structure of SOD were altered by PS-MPs, resulting in decreased α-helix and ß-sheet content. After PS-MPs exposure, fluorescence sensitization occurred, and micelles were formed, along with the enhanced hydrophobicity of aromatic amino acids in SOD. Moreover, the resonance light scattering (RLS) spectra result suggested that the PS-MPs and SOD combined to form a larger complex. Eventually, the activity of SOD was increased due to these structural changes, and the concentration of PS-MPs is positively correlated with SOD activity. This study can provide experimental support for studying the toxicological effects of PS-MPs.


Asunto(s)
Poliestirenos , Contaminantes Químicos del Agua , Poliestirenos/metabolismo , Microplásticos , Plásticos , Superóxido Dismutasa , Contaminantes Químicos del Agua/metabolismo , Análisis Espectral
16.
Chemosphere ; 323: 138199, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36813000

RESUMEN

Microplastics (MPs) undergo physical, chemical, and biological aging in the environment, leading to changes in their physicochemical properties, affecting migration characteristics and toxicity. Oxidative stress effects induced by MPs in vivo have been extensively studied, but the toxicity difference between virgin and aged MPs and the interactions between antioxidant enzymes and MPs in vitro have not been reported yet. This study investigated the structural and functional changes of catalase (CAT) induced by virgin and aged PVC-MPs. It was shown that light irradiation aged the PVC-MPs, and the aging mechanism was photooxidation, resulting in a rough surface and appearing holes and pits. Because of the changes in physicochemical properties, aged MPs had more binding sites than virgin MPs. Fluorescence and synchronous fluorescence spectra results suggested that MPs quenched the endogenous fluorescence of CAT and interacted with tryptophane and tyrosine residues. The virgin MPs had no significant effect on the skeleton of CAT, while the skeleton and the polypeptide chains of CAT became loosened and unfolded after binding with the aged MPs. Moreover, the interactions of CAT with virgin/aged MPs increased the α-helix and decreased the ß-sheet contents, destroyed the solvent shell, and resulted in a dispersion of CAT. Due to the large size, MPs cannot enter the interior of CAT and have no effects on the heme groups and activity of CAT. The interaction mechanism between MPs and CAT may be that MPs adsorb CAT to form the protein corona, and aged MPs had more binding sites. This study is the first comprehensive investigation of the effect of aging on the interaction between MPs and biomacromolecules and highlights the potential negative effects of MPs on antioxidant enzymes.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Microplásticos/toxicidad , Plásticos , Catalasa , Antioxidantes , Estrés Oxidativo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
17.
Chem Biol Interact ; 382: 110648, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37495201

RESUMEN

Nanoplastics are emerging pollutants that pose a potential threat to the environment and organisms and are widely distributed in environmental samples and food chains. The accumulation of polystyrene nanoplastics (PS-NPs) in an organism can cause oxidative stress. Currently, toxicity studies of PS-NPs mainly focus on the individual and cellular levels, whereas few studies have been conducted on the molecular mechanisms of the interaction between PS-NPs and catalase (CAT). Based on this, CAT was chosen as the target receptor for molecular toxicity research to reveal the interaction mechanism at the molecular level between PS-NPs and CAT by using various spectroscopic means and enzyme activity detection methods. The results indicated that PS-NPs destroyed the secondary structure of CAT, causing its protein skeleton to loosen and unfold, increasing the content of α-helices, decreasing the content of ß-sheets, and exposing the position of the heme group. After exposure to PS-NPs, the internal fluorophore of CAT underwent fluorescence sensitization, resulting in a micelle-like structure, which enhanced the hydrophobicity of aromatic amino acids but did not change their polarity. In addition, the aggregation state of CAT was altered upon binding to PS-NPs, and the volume was further increased. Finally, these structural changes led to a gradual decrease in CAT activity. This study presents a comprehensive assessment of the toxicity of PS-NPs at the molecular level, which can provide more experimental support for the study of the biotoxicological efficacy of PS-NPs.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Poliestirenos/toxicidad , Poliestirenos/química , Microplásticos , Catalasa , Estrés Oxidativo , Nanopartículas/química , Contaminantes Químicos del Agua/toxicidad
18.
Bioresour Technol ; 369: 128513, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36538963

RESUMEN

Decentralized wastewater pollution in rural areas has become a serious problem for the rural environment. In this study, a novel rotating self-aerated biofilm reactor was developed for decentralized wastewater treatment without any aeration equipment. After the long-term operation of 110 days, the removal efficiency reached to 96.06 % (COD), 98.06 % (NH4+-N), and 62.58 % (TN) in the last phase. Under high dissolved oxygen level, the simultaneous nitrification-denitrification (SND) maintained at a stable ratio of 62.53 % and the denitrification rates reached over 28.37 mg/L/h. With the organic loading rate increased, key nitrogen functional bacterial communities such as anoxic denitrifiers (Thiothrix, Flavobacterium, Pseudoxanthomonas, Aquimonas and Azoarcus) and aerobic denitrifiers (Hydrogenophaga, Zoogloea and Terrimonas) increased obviously. Overall, microbial analysis and nitrogen metabolism pathway indicated that an integration of SND process was achieved in this single reactor by the combined action of nitrification, denitrification and comammox without any aeration equipment.


Asunto(s)
Desnitrificación , Nitrificación , Reactores Biológicos/microbiología , Biopelículas , Nitrógeno/metabolismo , Eliminación de Residuos Líquidos
19.
Bioresour Technol ; 385: 129426, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37392965

RESUMEN

To achieve energy-efficient treatment of the rural wastewater with satisfying performance, a novel immersed rotating self-aerated biofilm reactor (iRSABR) was proposed in this study. The iRSABR system showed better biofilm renewal performance and higher microbial activity. The effect of different regulation strategies on the iRSABR system was investigated in this study. The 70% immersion ratio and 4 r/min rotation speed (stage III) exhibited the best performance, with a total nitrogen removal efficiency of 86% and a simultaneous nitrification-denitrification (SND) rate of 76%, along with the highest electron transport system activity. The nitrogen removal pathway revealed that the SND was achieved through autotrophic/heterotrophic nitrification and aerobic/anoxic denitrification. The regulation strategy in the iRSABR system established a synergistic microbial community with main functional bacteria of nitrification (Nitrosomonas), anoxic denitrification (Flavobacterium, Pseudoxanthomonas), and aerobic denitrification (Thauera). This study highlighted the feasibility and adaptability of the iRSABR system toward energy-efficient rural wastewater treatment.


Asunto(s)
Desnitrificación , Nitrógeno , Nitrógeno/metabolismo , Reactores Biológicos , Nitrificación , Biopelículas
20.
Front Biosci (Landmark Ed) ; 28(11): 294, 2023 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-38062818

RESUMEN

BACKGROUND: Drosophila ubiquitin carboxy-terminal hydrolase L5 (Uch-L5) functions as a critical component of the 26S proteasome to mediate degradation of polyubiquitinated proteins. It was recently shown to modulate tissue/organ development by targeting the Smoothened protein in the hedgehog pathway. However, whether it plays a role in controlling organismal immune response remains largely unknown. METHODS: Reverse transcription plus quantitative polymerase chain reaction (RT-qPCR), dual-luciferase, and Western blot assays were used to explore the potential function of Uch-L5 in the innate immune regulation in cultured Drosophila S2 cells. Further genetic manipulations and bacterial infections were conducted to confirm the findings in vivo. RESULTS: Silencing of Uch-L5 antagonizes the immune deficiency (IMD) but not the Toll innate immune signaling both in vitro and in vivo. Moreover, Uch-L5 positively contributes to the Drosophila innate immune response via its N-terminal Uch domain, which is the catalytical triad executing its deubiquitinase activity. CONCLUSIONS: Our studies shed light on a novel function of the deubiquitinase Uch-L5 in governing the anti-microbial defense in Drosophila.


Asunto(s)
Infecciones Bacterianas , Ubiquitina Tiolesterasa , Animales , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Proteínas Hedgehog , Drosophila , Inmunidad Innata/genética
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