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Plastic and microplastic pollution in the environment has become a significant global concern. Biodegradable plastics (BPs), as environmentally friendly alternatives to conventional plastics, have also emerged as a crucial topic of global discussion. The successful application of BPs appears to offer a solution to the potential ecological risks posed by conventional plastics. However, BPs have negative impacts on the ecological environment and human health. BPs can gradually degrade into biodegradable microplastics (BMPs) in the environment. Wastewater treatment plants (WWTPs) have become an undeniable source and sink of microplastics. With the production and application of BPs, BMPs will inevitably enter WWTPs. This paper reviews the pollution status, degradation behavior of BMPs, and their potential impact on wastewater treatment performance. The focus is on the environmental behavior of BMPs in wastewater treatment systems. The influences of BMPs on microbial communities, sludge treatment, and disposal are thoroughly discussed. The results indicate that BMPs are more easily decomposed into micro/nanoplastics and release additives compared to conventional microplastics. The effects of BMPs on microbial communities and wastewater treatment depend on their characteristics. The numerous oxygen-containing functional groups on the surface of BMPs enable them to serve a dual purpose as transport media and potential sources of environmental pollutants. Finally, in light of existing knowledge gaps, suggestions and prospects for future research on BMPs are proposed.
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The rise of operational noise as an environmental pollutant for farm animals is an emerging concern. The mechanisms through which music can alleviate oxidative stress, inflammation, and apoptosis induced by noise exposure remain underexplored. This study aims to investigate the alleviating effects and underlying mechanisms of long-term music exposure on noise-induced damage to the chicken spleen. Male Arbor Acres (AA) broilers were divided into four groups: control (C), acute noise stimulation (NS), noise stimulation with music mitigation (NSM), and music only (M). NS and NSM groups were exposed to noise (simulating sudden intensity noise, 115 to 120dB) for 10 minutes daily for a week, starting at 14-days-old. NSM and M groups then received 28 days of 6-hour daily music (Mozart K.448, 60-65 dB). The results showed that noise stimulation significantly activated the Keap-1/Nrf2 and NF-κB signaling pathways. Long-term music intervention has also been demonstrated to successfully mitigate oxidative stress and abnormal apoptosis induced by acute noise stimulation. Microscopic examination of the spleen revealed that acute noise stimulation resulted in an increase in splenic cells, a decrease in lymphocytes, and blurred boundaries between the red and white pulps in the NS group. However, these pathological changes were alleviated in the NSM group following music intervention. Compared with the control group, the NS group exhibited significantly elevated oxidative stress parameters. In contrast, music intervention in the NSM group notably improved antioxidant capacity and partially alleviated morphological abnormalities in the spleen. Additionally, noise stimulation activated the NF-κB pathway, upregulating the downstream genes of the inflammatory factors IL-1ß, IL-6, and TNF-α. Noise-induced mitochondrial damage led to apoptosis, as observed by TUNEL staining, along with increased gene and protein expression of Bcl-2, Bax, Cyt-C, Casp-3, Casp-8, and Casp-9. These findings indicate that acute noise exposure can induce splenic damage via oxidative stress, inflammation, and apoptosis by modulating the Keap-1/Nrf2 and NF-κB pathways. Prolonged music stimulation effectively mitigates noise-induced damage, offering a vital experimental foundation for further research on noise pollution's impact on organisms and music's alleviating role.
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Neuroinflammation may play an important role in the development of Alzheimer's disease (AD). Previous studies have reported that lipopolysaccharide (LPS)-induced neuroinflammation causes memory impairments and behavioral disorders. We investigated the potential preventive effects of punicalin (PUN), a polyphenolic component of pomegranate, on LPS-induced memory deficiency and anxiety- and depression-like behaviors, along with the underlying mechanisms. LPS-treated cultured microglial BV2 cells and BV2 cell/Neuro-2a (N2a) cell coculture system were investigated for anti-neuroinflammatory effects of PUN in vitro. The in vivo experiments involved mice administered a 4-week course of oral gavage with 1500 mg/kg/d PUN before intraperitoneal LPS (250 mg/kg daily 7 times) injections. The in vitro results demonstrated that PUN inhibited the LPS-induced inflammatory cytokine (IL-18, IL-1ß, TNF-É, and IL-6) production in BV2 cells and protected N2a cells from synaptic damage mediated by BV2 microglia-induced neuroinflammation. In in vivo studies, it was observed that PUN improved memory impairment and anxiety- and depression-like behaviors caused by LPS and reduced the expression of inflammatory proteins such as iNOS, COX-2, IL-1ß, IL-2, IL-6, and TNF-α. Furthermore, PUN inhibited the LPS-induced production of MDA; increased the activities of CAT, SOD, and GSH-Px, and inhibited LPS-induced Aß1-42 generation through down-regulation of APP and BACE1 expression. Moreover, PUN also suppressed the expression of TLR4, IRAK4, TRAF6, IKK-ß, NF-κB, p65, and HMGB1 in LPS-treated mouse brain and cultured microglial BV-2 cells. These results suggest that PUN inhibits LPS-induced memory impairment via anti-inflammatory and anti-amylogenic mechanisms through inhibition of TLR4-NF-kB activation.
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Lipopolissacarídeos , Transtornos da Memória , Microglia , NF-kappa B , Doenças Neuroinflamatórias , Estresse Oxidativo , Punica granatum , Receptor 4 Toll-Like , Animais , Receptor 4 Toll-Like/metabolismo , Camundongos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Masculino , Punica granatum/química , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/induzido quimicamente , Microglia/efeitos dos fármacos , Microglia/metabolismo , Transdução de Sinais/efeitos dos fármacos , Polifenóis/farmacologia , Peptídeos beta-Amiloides , Linhagem Celular , Citocinas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/induzido quimicamente , Depressão/tratamento farmacológico , Depressão/induzido quimicamente , Ansiedade/tratamento farmacológico , Ansiedade/induzido quimicamente , Camundongos Endogâmicos C57BL , Comportamento Animal/efeitos dos fármacos , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico EndopeptidasesRESUMO
Effective nitrate removal is a key challenge when treating low carbon-to-nitrogen ratio wastewater. How to select an effective inorganic electron donor to improve the autotrophic denitrification of nitrate nitrogen has become an area of intense research. In this study, the nitrate removal mechanism of three iron-based materials in the presence and absence of microorganisms was investigated with Fe2+/Fe0 as an electron donor and nitrate as an electron acceptor, and the relationship between the iron materials and denitrifying microorganisms was explored. The results indicated that the nitrogen removal efficiency of each iron-based material coupled sludge systems was higher than that of iron-based material. Furthermore, compared with the sponge iron coupled sludge system (60.6%-70.4%) and magnetite coupled sludge (56.1%-65.3%), the pyrite coupled sludge system had the highest removal efficiency of TN, and the removal efficiency increased from 62.5% to 82.1% with time. The test results of scanning electron microscope, X-ray photoelectron spectroscopy and X-ray diffraction indicated that iron-based materials promoted the attachment of microorganisms and the chemical reduction of nitrate in three iron-based material coupled sludge systems. Furthermore, the pyrite coupled sludge system had the highest nitrite reductase activity and can induce microorganisms to secrete more extracellular polymer substances. Combined with high-throughput sequencing and PICRUSt2 functional predictive analysis software, the total relative abundance of the dominant bacterial in pyrite coupled sludge system was the highest (72.06%) compared with the other iron-based material systems, and the abundance of Blastocatellaceae was relatively high. Overall, these results suggest that the pyrite coupled sludge system was more conducive to long-term stable nitrate removal.
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Processos Autotróficos , Carbono , Desnitrificação , Ferro , Nitratos , Nitrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Nitratos/metabolismo , Ferro/química , Ferro/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Carbono/química , Eliminação de Resíduos Líquidos/métodos , Esgotos/microbiologia , Esgotos/química , Poluentes Químicos da Água/metabolismo , Oxirredução , Sulfetos/química , Sulfetos/metabolismoRESUMO
Hydroxyl radicals (·OH) generated during the flooding-drought transformation process play a vital role in affecting nutrient cycles at riparian zone. However, information on the processes and mechanisms for ·OH formation under the influence of microplastics (MPs) remains unclear. In this study, the effects of MPs on ·OH production from riparian sediments with different biomass [e.g., vegetation lush (VL) and vegetation barren (VB)] were studied. The results showed that presence of MPs inhibited the production of ·OH by 27 % and 7.5 % for VB and VL sediments, respectively. The inhibition was mainly resulted from the MP-induced reduction of the biotic and abiotic mediated Fe redox processes. Spectral analysis revealed that VL sediments contained more high-molecular-weight humic-like substances. Presence of MPs increased the abundances and activities of Proteobacteria, Acidobacteria and Actinobacteria, which were conducive to the changes in humification and polar properties of organic matters. The reduced humic- and fulvic-like substances were accumulated in the flooding period and substantially oxidized during flooding/drought transformation due to the enhanced MP-mediated electron transfer abilities, thus mitigated the MP-induced inhibition effects. Therefore, in order to better understanding the biogeochemical cycling of contaminants as influenced by ·OH and MPs in river ecosystems, humic substances should be considered systematically.
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Effective therapeutic interventions for elderly patients are lacking, despite advances in pharmacotherapy. Methylated urolithin A (mUro A), a modified ellagitannin (ET)-derived metabolite, exhibits anti-inflammatory, antioxidative, and anti-apoptotic effects. Current research has primarily investigated the neuroprotective effects of mUroA in aging mice and explored the underlying mechanisms. Our study used an in vivo aging model induced by d-galactose (D-gal) to show that mUro A notably improved learning and memory, prevented synaptic impairments by enhancing synaptic protein expression and increasing EPSCs, and reduced oxidative damage in aging mice. mUro A alleviated the activation of the NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome, leading to reduced glial cell activity and neuroinflammation in both accelerated aging and naturally senescent mouse models. Moreover, mUroA enhanced the activity of TCA cycle enzymes (PDH, CS, and OGDH), decreased 8-OHdG levels, and raised ATP and NAD+ levels within the mitochondria. At the molecular level, mUro A decreased phosphorylated p53 levels and increased the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), thus enhancing mitochondrial function. In conclusion, mUro A alleviates cognitive impairment in aging mice by suppressing neuroinflammation through NLRP3 inflammasome inhibition and restoring mitochondrial function via the p53-PGC-1α pathway. This suggests its potential therapeutic agent for brain aging and aging-related diseases.
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Envelhecimento , Disfunção Cognitiva , Cumarínicos , Inflamassomos , Camundongos Endogâmicos C57BL , Mitocôndrias , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cumarínicos/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Camundongos , Masculino , Galactose , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismoRESUMO
Interconnected, fundamental aging processes are central to many illnesses and diseases. Cellular senescence is a mechanism that halts the cell cycle in response to harmful stimuli. Senescent cells (SnCs) can emerge at any point in life, and their persistence, along with the numerous proteins they secrete, can negatively affect tissue function. Interventions aimed at combating persistent SnCs, which can destroy tissues, have been used in preclinical models to delay, halt, or even reverse various diseases. Consequently, the development of small-molecule senolytic medicines designed to specifically eliminate SnCs has opened potential avenues for the prevention or treatment of multiple diseases and age-related issues in humans. In this review, we explore the most promising approaches for translating small-molecule senolytics and other interventions targeting senescence in clinical practice. This discussion highlights the rationale for considering SnCs as therapeutic targets for diseases affecting individuals of all ages.
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Senescência Celular , Senoterapia , Humanos , Senescência Celular/fisiologiaRESUMO
As an environmental enrichment, music can positively influence the immune function, while noise has an adverse effect on the physical and mental health of humans and animals. However, whether music-enriched environments mitigate noise-induced acute stress remains unclear. To investigate the anti-inflammatory effects of music on the immune organs of broiler chickens under conditions of early-life acute noise stress, 140 one-day-old white feather broilers (AA) were randomly divided into four groups: control (C), the music stimulation (M) group, the acute noise stimulation (N) group, the acute noise stimulation followed by music (NM) group. At 14 days of age, the N and NM groups received 120â¯dB noise stimulation for 10â¯min for one week. After acute noise stimulation, the NM group and M group were subjected to continuous music stimulation for 14 days (6â¯h per day, 60â¯dB). At 28 days of age, the body temperature of the chicks, the histopathological changes, quantification of ROS-positive density and apoptosis positivity in tissues of spleen, thymus, and bursa of Fabricius (BF) were measured. The results showed that acute noise stimulation led to an increase in the number and area of splenic microsomes and the cortex/medulla ratio of the detected immune organs. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of immune tissues of broilers in N group were decreased compared to the broilers in C group, while the mRNA levels of malondialdehyde (MDA), TNF-α, IL-1, and IL-1ß increased. In addition, the gene and protein expression levels of IKK, NF-κB, and IFN-γ of three immune organs from broilers in the N group were increased. Compared to the C and N group, chickens from the NM group showed a decrease in the number and area of splenic follicles, an increase in the activities of SOD and GSH-Px, and a decrease in the expression levels of MDA, TNF-α, IL-1, and IL-1ß. Therefore, a music-enriched environment can attenuate oxidative stress induced by acute noise stimulation, inhibiting the activation of the NF-κB signaling pathway and consequently alleviating the inflammatory response in immune organs.
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Música , NF-kappa B , Humanos , Animais , Pré-Escolar , NF-kappa B/genética , NF-kappa B/metabolismo , Galinhas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Estresse Oxidativo , Transdução de Sinais , Superóxido Dismutase/metabolismo , Interleucina-1/metabolismo , Interleucina-1/farmacologiaRESUMO
Obesity is a major risk factor for morbidity and mortality because it has a close relationship to metabolic illnesses, such as diabetes, cardiovascular diseases, and some types of cancer. With no drugs available, the mainstay of obesity management remains lifestyle changes with exercise and dietary modifications. In light of the tremendous disease burden and unmet therapeutics, fresh perspectives on pathophysiology and drug discovery are needed. The development of epigenetics provides a compelling justification for how environmental, lifestyle, and other risk factors contribute to the pathogenesis of obesity. Furthermore, epigenetic dysregulations can be restored, and it has been reported that certain natural products obtained from plants, such as tea polyphenols, ellagic acid, urolithins, curcumin, genistein, isothiocyanates, and citrus isoflavonoids, were shown to inhibit weight gain. These substances have great antioxidant potential and are of great interest because they can also modify epigenetic mechanisms. Therefore, understanding epigenetic modifications to target the primary cause of obesity and the epigenetic mechanisms of anti-obesity effects with certain phytochemicals can prove rational strategies to prevent the disease and develop novel therapeutic interventions. Thus, the current review aimed to summarize the epigenetic mechanisms and advances in therapies for obesity based on natural products to provide evidence for the development of several potential anti-obesity drug targets.
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Fármacos Antiobesidade , Neoplasias , Humanos , Obesidade/tratamento farmacológico , Obesidade/genética , Obesidade/metabolismo , Epigênese Genética , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêuticoRESUMO
The behavior and composition of hydrochar-based dissolved organic matter (DOM) would affect the efficiency of copper (Cu) removal from wastewater through adsorption. In this study, the reed was hydrolyzed in the presence of feedwater with and without ZnCl2, FeCl3, and SnCl4 to produce pristine hydrochars (PHCs), which were named H2O-HC, ZnCl2-HC, FeCl3-HC, and SnCl4-HC. After removal of DOM, washed hydrochars (WHCs) were obtained, labelled as W-H2O-HC, W-ZnCl2-HC, W-FeCl3-HC, and W-SnCl4-HC. The release dynamics of DOM from PHCs were analyzed, and the adsorption behaviors of Cu2+ on both PHCs and WHCs were investigated. The results showed that chloride-modifications were beneficial for the porosity, specific surface area (SSA), and functional groups of WHCs. Meanwhile, the quantity of hydrochar-based DOM was significantly affected by chloride-modifications. In particular, the relative contents of Ar-P and Fa-L in the DOM released from hydrochars varied with time and modification. Furthermore, the Qe of Cu2+ adsorption on WHCs followed the order of W-SnCl4-HC > W-FeCl3-HC > W-ZnCl2-HC > W-H2O-HC at 15 °C. Compared to PHCs, the adsorption capacity of Cu2+ on WHCs was improved by 7.15-119.77% at the temperature of 35 °C. Simultaneously, the adsorption capacity of Cu2+ in WHCs showed a significant correlation with the SSA via physical adsorption (P < 0.05). Moreover, XPS analysis revealed that Cu2+ adsorption also occurred via complexation and chelation through newly formed Cu-O group between W-SnCl4-HC and Cu2+. Notably, the increase of Cu2+ adsorption in WHCs was significantly correlated with the release of Fa-L and Ar-P from PHCs (P < 0.05). This study found that the content and composition of hydrochar-based DOM could be a major driving factor for Cu2+ adsorption.
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Aims: To investigate the optimal thresholds and diagnostic efficacy of commonly used serological and synovial fluid detection indexes for diagnosing periprosthetic joint infection (PJI) in patients who have rheumatoid arthritis (RA). Methods: The data from 348 patients who had RA or osteoarthritis (OA) and had previously undergone a total knee (TKA) and/or a total hip arthroplasty (THA) (including RA-PJI: 60 cases, RA-non-PJI: 80 cases; OA-PJI: 104 cases, OA-non-PJI: 104 cases) were retrospectively analyzed. A receiver operating characteristic curve was used to determine the optimal thresholds of the CRP, ESR, synovial fluid white blood cell count (WBC), and polymorphonuclear neutrophil percentage (PMN%) for diagnosing RA-PJI and OA-PJI. The diagnostic efficacy was evaluated by comparing the area under the curve (AUC) of each index and applying the results of the combined index diagnostic test. Results: For PJI prediction, the results of serological and synovial fluid indexes were different between the RA-PJI and OA-PJI groups. The optimal cutoff value of CRP for diagnosing RA-PJI was 12.5 mg/l, ESR was 39 mm/hour, synovial fluid WBC was 3,654/µl, and PMN% was 65.9%; and those of OA-PJI were 8.2 mg/l, 31 mm/hour, 2,673/µl, and 62.0%, respectively. In the RA-PJI group, the specificity (94.4%), positive predictive value (97.1%), and AUC (0.916) of synovial fluid WBC were higher than those of the other indexes. The optimal cutoff values of synovial fluid WBC and PMN% for diagnosing RA-PJI after THA were significantly higher than those of TKA. The specificity and positive predictive value of the combined index were 100%. Conclusion: Serum inflammatory and synovial fluid indexes can be used for diagnosing RA-PJI, for which synovial fluid WBC is the best detection index. Combining multiple detection indexes can provide a reference basis for the early and accurate diagnosis of RA-PJI.
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How to reduce microplastic pollution in aquatic ecosystem has become the focus of the global attention. The re-removal of microplastics of wastewater treatment plant (WWTP) effluent is gradually being put on the agenda. Recently, algae have been used as an ecofriendly remediation strategy for microplastic removal. Microplastics in sewage can be removed by algae through interception, capture, and entanglement, and can also form heterogeneous aggregates with algae, thereby reducing their free suspensions. Algae can recover nitrogen and carbon from wastewater and can be made into biochar, biofertilizers, and biofuels. However, problematically, this technology has been in the laboratory research stage, and existing research results cannot provide effective basis for its application. Microplastic removal via algae is influenced by wastewater flow rate, microplastic types, and pollutants. Microplastics are only physically fixed by algae, and ensuring that microplastics do not re-enter the environment during resource and capacity recovery is also a key factor limiting the implementation of this technology. The topic of this paper is to discuss the performance of the current tertiary wastewater treatment process - algae process to remove microplastics. Algae can remove nitrogen and phosphorus pollutants in sewage and remove microplastics at the same time, which can realize energy recovery and reduce ecological risks of the effluent. Although algae combined tertiary sewage treatment is a green technology for microplastic removal, its application still needs to be explored. The key challenges that need to be addressed, from single laboratory conditions to complex conditions, from small-scale testing to large-scale simulations, lie ahead of the application of this friendly technology.
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Águas Residuárias , Poluentes Químicos da Água , Microplásticos , Esgotos , Eliminação de Resíduos Líquidos/métodos , Plásticos , Ecossistema , Poluentes Químicos da Água/análise , Nitrogênio , Monitoramento AmbientalRESUMO
As a means of environmental enrichment, music environment has positive and beneficial effects on biological neural development. Kunming white mice (61 days old) were randomly divided into the control group (group C), the group of D-tone (group D), the group of A-tone (group A) and the group of G-tone (group G). They were given different tonal music stimulation (group A) for 14 consecutive days (2 h/day) to study the effects of tonal music on the neural development of the hippocampus and prefrontal cortex of mice in early life and its molecular mechanisms. The results showed that the number of neurons in the hippocampus and prefrontal cortex of mice increased, with the cell morphology relatively intact. In addition, the number of dendritic spines and the number of dendritic spines per unit length were significantly higher than those in group C, and the expressions of synaptic plasticity proteins (SYP and PSD95) were also significantly elevated over those in group C. Compared with group C, the expression levels of BDNF, TRKB, CREB, PI3K, AKT, GS3Kß, PLCγ1, PKC, DAG, ERK and MAPK genes and proteins in the hippocampus and prefrontal cortex of mice in the music groups were up-regulated, suggesting that different tones of music could regulate neural development through BDNF and its downstream pathways. The enrichment environment of D-tone music is the most suitable tone for promoting the development of brain nerves in early-life mice. Our study provides a basis for screening the optimal tone of neuroplasticity in early-life mice and for the treatment of neurobiology and neurodegenerative diseases.
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Fator Neurotrófico Derivado do Encéfalo , Encéfalo , Música , Animais , Camundongos , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Plasticidade Neuronal/fisiologia , Receptor trkB/genética , Receptor trkB/metabolismoRESUMO
Effluent from sewage treatment plant, as an important source of microplastics (MPs) in receiving water, has attracted extensive attention. Membrane separation process shows good microplastic removal performance in the existing tertiary water treatment process. Problematically, membrane fouling and insufficient removal of small organic molecules are still the key obstacles to its further extensive application. Dissolved organics, extracellular polymers and suspended particles in the influent are deposited on the membrane surface and internal structure, reducing the number and pore diameter of effective membrane aperture, and increasing the resistance of membrane filtration. Exploring the mechanism and approach of membrane fouling caused by micro/nanoplastics is the key to alleviate fouling and allow membranes to operate longer. In this paper, removal performance of micro/nanoplastics by current membrane filtration and the contribution to membrane fouling during water treatment are thoroughly reviewed. The coupling mechanisms between micro/nanoplastics and other pollutants and mechanism of membrane fouling caused by composite micro/nanoplastics are discussed. Additionally, on this basis, the prospect of combined process for micro/nanoplastic removal and membrane fouling prevention is also proposed and discussed, which provides a valuable reference for the preferential removal of micro/nanoplastics and development of antifouling membrane.
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Microplastics (MPs), as emerging contaminants can behave as carriers for heavy metals in the water environments. Although the adsorption performance of heavy metals on MPs has been widely investigated, the effects of humic acids (HA) on the adsorption have seldom been explored. The authors were compared the Pb(II) adsorption onto biofilm-developed polyvinyl chloride (Bio-PVC) MPs with Pb(II) adsorption onto virgin PVC MPs (V-PVC), and explored the relationship between surface characteristics and the adsorption properties in the coexistence of HA. Our results showed that due to a larger specific surface area and more oxygen containing groups, Bio-PVC had a larger adsorption capability with a value of 3.57 mg/g than original ones (1.85 mg/g) due to its huge specific surface area and more oxygen containing groups. Microbial community analysis showed that the predominate bacteria in biofilms as Proteobacteria, Acidobacteria, Cyanobacteria, Firmicutes, and Bacteroidetes. Notably, the Pb(II) adsorption onto the V-PVC surfaces was increased, but the adsorption capacities of Pb(II) on Bio-PVC were suppressed with increasing HA. With the co-existence of HA, the increasing complexation and electrostatic attraction had attributed to the increased Pb(II) adsorption ability on V-PVC. Except for its competitive ability, HA has a shield effect which decreases the sorption sites on Bio-PVC. Overall, our findings provide a better understanding of the HA effect on the adsorption mechanism of heavy metals onto MPs in aquatic ecosystems.
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Metais Pesados , Microbiota , Poluentes Químicos da Água , Microplásticos , Plásticos , Substâncias Húmicas , Chumbo , Adsorção , Poluentes Químicos da Água/análise , Água , Íons , BiofilmesRESUMO
Many lakes are suffering from eutrophication and heavy metals-contamination. However, the combined impacts of algae bloom and its induced variations in heavy metals on microbial community in sediment from eutrophic lakes remain unclear. In this study, we performed field experiments to investigate how algae bloom impacted water soluble organic matter (WSOM) and heavy metals in sediment from Chaohu Lake, a eutrophic shallow lake, and probed their combined impacts on sediment bacterial community structure. The results showed that algae bloom increased WSOM quantity, in particular, the soluble microbial by-product-like (SMP) and fulvic acid-like (Fa-L) components markedly enhanced by 203.70 % and 70.17 %, respectively. We also found that algae bloom redistributed the spatial patterns of heavy metals and altered their chemical species in sediment, then promoted contamination degree and potential ecological risk of heavy metals in sediment. Moreover, sediment bacterial community richness and diversity obviously decreased after algae bloom, and the variance partitioning analysis (VPA) results showed that combined impacts of algae-induced changes in WSOM and heavy metals explained 66.56 % of the variations in bacterial community structure. These findings depicted how algae bloom influence sediment WSOM and heavy metals, and revealed the combined impacts of algae-induced variations on microbial community structure in shallow eutrophic lake.
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Metais Pesados , Poluentes Químicos da Água , Água/análise , Lagos/química , Sedimentos Geológicos/química , Metais Pesados/toxicidade , Metais Pesados/análise , Eutrofização , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , ChinaRESUMO
Keel bone fractures affect welfare, health, and production performance in laying hens. A total of one hundred and twenty 35-wk-old Hy-line Brown laying hens with normal keel (NK) bone were housed in furnished cages and studied for ten weeks to investigate the underlying mechanism of keel bone fractures. At 45 wk of age, the keel bone state of birds was assessed by palpation and X-ray, and laying hens were recognized as NK and fractured keel (FK) birds according to the presence or absence of fractures in keel bone. The serum samples of 10 NK and 10 FK birds were collected to determine bone metabolism-related indexes and slaughtered to collect keel bones for RNA-sequencing (RNA-seq), Micro-CT, and histopathological staining analyses. The results showed that the concentrations of Ca, phosphorus, calcitonin, 25-hydroxyvitamin D3, and osteocalcin and activities of alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP) in serum samples of FK birds were lower than those of NK birds (P < 0.05), but the concentrations of parathyroid hormone, osteoprotegerin, and corticosterone in serum samples of FK birds were higher than those of NK birds (P < 0.05). TRAP staining displayed that FK bone increased the number of osteoclasts (P < 0.05). Micro-CT analysis indicated that FK bone decreased bone mineral density (P < 0.05). Transcriptome sequencing analysis of NK and FK bones identified 214 differentially expressed genes (DEGs) (|log2FoldChange| > 1, P < 0.05), among which 88 were upregulated and 126 downregulated. Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) analysis indicated that 14 DEGs related to skeletal muscle movement and bone Ca transport (COL6A1, COL6A2, COL6A3, PDGFA, MYLK2, EGF, CAV3, ADRA1D, BDKRB1, CACNA1S, TNN, TNNC1, TNNC2, and RYR3) were enriched in focal adhesion and Ca signaling pathway, regulating bone quality. This study suggests that abnormal bone metabolism related to keel bone fractures is possibly responded to fracture healing in laying hens.
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Galinhas , Fraturas Ósseas , Animais , Feminino , Galinhas/genética , Fraturas Ósseas/genética , Fraturas Ósseas/veterinária , Fraturas Ósseas/patologia , Osso e Ossos/patologia , Densidade Óssea , Abrigo para Animais , Remodelação ÓsseaRESUMO
Massive production and spread application of plastics have led to the accumulation of numerous plastics in the global environment so that the proportion of carbon storage in these polymers also increases. Carbon cycle is of fundamental significance to global climate change and human survival and development. With the continuous increase of microplastics, undoubtedly, there carbons will continue to be introduced into the global carbon cycle. In this paper, the impact of microplastics on microorganisms involved in carbon transformation is reviewed. Micro/nanoplastics affect carbon conversion and carbon cycle by interfering with biological fixation of CO2, microbial structure and community, functional enzymes activity, the expression of related genes, and the change of local environment. Micro/nanoplastic abundance, concentration and size could significantly lead to difference in carbon conversion. In addition, plastic pollution can further affect the blue carbon ecosystem reduce its ability to store CO2 and marine carbon fixation capacity. Nevertheless, problematically, limited information is seriously insufficient in understanding the relevant mechanisms. Accordingly, it is required to further explore the effect of micro/nanoplastics and derived organic carbon on carbon cycle under multiple impacts. Under the influence of global change, migration and transformation of these carbon substances may cause new ecological and environmental problems. Additionally, the relationship between plastic pollution and blue carbon ecosystem and global climate change should be timely established. This work provides a better perspective for the follow-up study of the impact of micro/nanoplastics on carbon cycle.
Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Ecossistema , Carbono , Dióxido de Carbono , Seguimentos , Ciclo do Carbono , Poluentes Químicos da Água/análiseRESUMO
Ammonia (NH3) is a harmful gas in livestock houses. So far, many researchers have demonstrated that NH3 is detrimental to animal and human organs. Selenium (Se) is one of the essential trace elements in the body and has a good antioxidant effect. However, there was little conclusive evidence that Se alleviated NH3 poisoning. To investigate the toxic mechanism of NH3 on pig spleen and the antagonistic effect of L-selenomethionine, a porcine NH3-poisoning model and an L-selenomethionine intervention model were established in this study. Our results showed that NH3 exposure increased the apoptosis rate, while L-selenomethionine supplementation alleviated the process of excessive apoptosis. Immunofluorescence staining, real-time quantitative polymerase chain reaction (qRT-PCR), and western blot results confirmed that exposure to NH3 changed the expression levels of interleukin family factors, apoptosis, death receptor, and oxidative stress factors. Our study further confirmed that excessive NH3 induced inflammatory response and mediated necroptosis leading to cell apoptosis by activating the Nrf2 signaling pathway. Excessive NH3 could mediate spleen injury through oxidative stress-induced mitochondrial dynamics disorder. L-Selenomethionine could alleviate inflammation and abnormal apoptosis by inhibiting the IL-17/TNF-α/FADD axis. Our study would pave the way for comparative medicine and environmental toxicology.