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1.
J Environ Manage ; 366: 121865, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39018858

RESUMEN

Landfill leachate is an important source of microplastics (MPs) and antibiotic-resistance genes (ARGs). Here, in the presence of polystyrene MPs (PS-MPs) and polyethylene MPs (PE-MPs), the nitrogen and phosphorus removal effect and sludge structure performance were affected in an anaerobic-anoxic-aerobic system, a typical biological leachate treatment process. The abundance of tetracycline-resistance genes (tet genes) in biofilms on the two types of MP was significantly higher than that in the leachate and sludge, and the load on PE-MPs was higher than that on PS-MPs because of the porous structure of PE-MPs. Aging of the MPs increased their surface roughness and abundance of oxygen-containing functional groups and shaped the profile of ARGs in the MP biofilms. The biofilm biomass and growth rate on the two types of MP increased with the incubation time in the first 30 days, and was affected by environmental factors. Structural equation models and co-occurrence network analysis demonstrated that the MPs indirectly affected the spectrum of ARGs by affecting biofilm formation, and, to a lesser extent, had a direct impact on the selective enrichment of ARGs. We discuss the mechanisms of the relationships between MPs and ARGs in the leachate treatment system, which will have guiding significance for future research. Our data on the colonization of microorganisms and tet genes in MPs biofilms provide new evidence concerning the accumulation and transmission of these ARGs, and are important for understanding the mechanisms of MPs in spreading pollution.

2.
Bone Res ; 12(1): 39, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987555

RESUMEN

Wnts are secreted, lipid-modified proteins that bind to different receptors on the cell surface to activate canonical or non-canonical Wnt signaling pathways, which control various biological processes throughout embryonic development and adult life. Aberrant Wnt signaling pathway underlies a wide range of human disease pathogeneses. In this review, we provide an update of Wnt/ß-catenin signaling components and mechanisms in bone formation, homeostasis, and diseases. The Wnt proteins, receptors, activators, inhibitors, and the crosstalk of Wnt signaling pathways with other signaling pathways are summarized and discussed. We mainly review Wnt signaling functions in bone formation, homeostasis, and related diseases, and summarize mouse models carrying genetic modifications of Wnt signaling components. Moreover, the therapeutic strategies for treating bone diseases by targeting Wnt signaling, including the extracellular molecules, cytosol components, and nuclear components of Wnt signaling are reviewed. In summary, this paper reviews our current understanding of the mechanisms by which Wnt signaling regulates bone formation, homeostasis, and the efforts targeting Wnt signaling for treating bone diseases. Finally, the paper evaluates the important questions in Wnt signaling to be further explored based on the progress of new biological analytical technologies.


Asunto(s)
Enfermedades Óseas , Homeostasis , Osteogénesis , Vía de Señalización Wnt , Humanos , Animales , Osteogénesis/fisiología , Enfermedades Óseas/metabolismo , Enfermedades Óseas/terapia , beta Catenina/metabolismo , Proteínas Wnt/metabolismo
4.
Theor Appl Genet ; 137(7): 170, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38913206

RESUMEN

The timely degradation of tapetum, the innermost somatic anther cell layer in flowering plants, is critical for pollen development. Although several genes involved in tapetum development have been characterized, the molecular mechanisms underlying tapetum degeneration remain elusive. Here, we showed that mutation in Abnormal Degraded Tapetum 1 (ADT1) resulted in overaccumulation of Reactive Oxygen Species (ROS) and abnormal anther development, causing earlier tapetum Programmed Cell Death (PCD) and pollen abortion. ADT1 encodes a nuclear membrane localized protein, which is strongly expressed in the developing microspores and tapetal cells during early anther development. Moreover, ADT1 could interact with metallothionein MT2b, which was related to ROS scavenging and cell death regulation. These findings indicate that ADT1 is required for proper timing of tapetum PCD by regulating ROS homeostasis, expanding our understanding of the regulatory network of male reproductive development in rice.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Mutación , Oryza , Proteínas de Plantas , Polen , Especies Reactivas de Oxígeno , Oryza/genética , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Polen/crecimiento & desarrollo , Polen/genética , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Muerte Celular , Flores/crecimiento & desarrollo , Flores/genética , Apoptosis
5.
Ann Med ; 56(1): 2361843, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38830017

RESUMEN

BACKGROUND: Literature on the safety of remdesivir in hospitalized COVID-19 patients with severe renal impairment is limited. We aimed to investigate the safety and effectiveness of remdesivir in this population. METHODS: We conducted a retrospective cohort study of adult hospitalized COVID-19 patients who received remdesivir between April 2022 and October 2022. Outcomes were compared between estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 and ≥30 mL/min/1.73 m2 groups. The primary safety outcomes were acute kidney injury (AKI) and bradycardia, while the primary effectiveness outcomes included mortality in COVID-19-dedicated wards and hospital mortality. Secondary outcomes included laboratory changes, disease progression, and recovery time. RESULTS: A total of 1,343 patients were recruited, with 307 (22.9%) in the eGFR <30 group and 1,036 (77.1%) in the eGFR ≥30 group. Patients with an eGFR <30 had higher risks of AKI (adjusted hazard ratio [aHR] 2.92, 95% CI 1.93-4.44) and hospital mortality (aHR 1.47, 95% CI 1.06-2.05) but had comparable risks of bradycardia (aHR 1.15, 95% CI 0.85-1.56) and mortality in dedicated wards (aHR 1.43, 95% CI 0.90-2.28) than patients with an eGFR ≥30. Risk of disease progression was higher in the eGFR <30 group (adjusted odds ratio 1.62, 95% CI 1.16-2.26). No difference between the two groups in laboratory changes and recovery time. CONCLUSIONS: Hospitalized COVID-19 patients receiving remdesivir with severe renal impairment had an increased risk of AKI, hospital mortality, and COVID-19 disease progression compared to patients without severe renal impairment.


Asunto(s)
Lesión Renal Aguda , Adenosina Monofosfato , Alanina , Antivirales , Tratamiento Farmacológico de COVID-19 , Tasa de Filtración Glomerular , Mortalidad Hospitalaria , Hospitalización , SARS-CoV-2 , Humanos , Alanina/análogos & derivados , Alanina/uso terapéutico , Alanina/efectos adversos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/uso terapéutico , Adenosina Monofosfato/efectos adversos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Antivirales/uso terapéutico , Antivirales/efectos adversos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Hospitalización/estadística & datos numéricos , COVID-19/complicaciones , COVID-19/mortalidad , Resultado del Tratamiento , Insuficiencia Renal/epidemiología , Bradicardia/inducido químicamente , Bradicardia/epidemiología , Adulto
6.
J Hazard Mater ; 473: 134582, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38776810

RESUMEN

Sulfate-reducing bacteria (SRB) are generally found in sanitary landfills and play a role in sulfur (S) and metal/metalloid geochemical cycling. In this study, we investigated the influence of SRB on arsenic (As) metabolic pathways in refuse-derived cultures. The results indicated that SRB promote As(III) methylation and are beneficial for controlling As levels. Heterotrophic and autotrophic SRB showed significant differences during As cycling. In heterotrophic SRB cultures, the As methylation rate increased with As(III) concentration in the medium and reached a peak (85.1%) in cultures containing 25 mg L-1 As(III). Moreover, 4.0-12.6% of SO42- was reduced to S2-, which then reacted with As(III) to form realgar (AsS). In contrast, autotrophic SRB oxidized As(III) to less toxic As(V) under anaerobic conditions. Heterotrophic arsM-harboring SRB, such as Desulfosporosinus, Desulfocurvibacter, and Desulfotomaculum, express As-related genes and are considered key genera for As methylation in landfills. Thiobacillus are the main autotrophic SRB in landfills and can derive energy by oxidizing sulfur compounds and metal(loid)s. These results suggest that different types of SRB drive As methylation, redox reaction, and mineral formation in landfills. These study findings have implications for the management of As pollutants in landfills and other contaminated environments.


Asunto(s)
Arsénico , Sulfatos , Instalaciones de Eliminación de Residuos , Arsénico/metabolismo , Sulfatos/metabolismo , Sulfatos/química , Oxidación-Reducción , Metilación , Bacterias/metabolismo , Bacterias/genética , Biodegradación Ambiental , Contaminantes Químicos del Agua/metabolismo
7.
Phytopathology ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809607

RESUMEN

Fusarium head blight (FHB) of wheat, mainly caused by Fusarium graminearum, leads to severe economic losses worldwide. Effective management measures for controlling FHB are not available, due to a lack of resistant cultivars. Currently, the utilization of biological control is a promising approach that can be used to help manage FHB. Previous studies have confirmed that Streptomyces pratensis S10 harbors excellent inhibitory effects on F. graminearum. However, there is no information regarding invasive hyphae of F. graminearum are inhibited by S10. Thus, we investigated the effects of S10 on F. graminearum strain PH-1 hyphae extension, toxisome formation, and TRI5 gene expression on wheat plants via microscopic observation. The results showed that S10 effectively inhibited spread of F. graminearum hyphae along the rachis, restricting the infection of neighboring florets via the phloem. In the presence of S10, the hyphal growth is impeded by formation of dense cell wall thickenings in the rachis internode surrounding the F. graminearum infection site, avoiding cell plasmolysis and collapse. We further demonstrated that S10 largely prevented cell-to-cell invasion of fungal hyphae inside wheat coleoptiles using a constitutively green fluorescence protein-expressing F. graminearum strain, PH-1. Importantly, S. pratensis S10 inhibited toxisome formation and TRI5 gene expression in wheat plants during infection. Collectively, these findings indicated that S. pratensis S10 prevents spread of F. graminearum invasive hyphae via the rachis.

8.
Skin Res Technol ; 30(4): e13696, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38602262

RESUMEN

BACKGROUND: Female pattern hair loss (FPHL) is the most prevalent type of alopecia among adult women. Presently, topical minoxidil stands as the sole treatment endorsed by the FDA. Addressing cases of FPHL in individuals who develop contact dermatitis in response to minoxidil can pose a challenge for dermatologists. OBJECTIVE: To assess the efficacy and safety of subcutaneous injections of Botulinum Toxin Type A (BTA) in treating FPHL. METHODS: Enrolled outpatients with FPHL who exhibited an allergic reaction to minoxidil solution. Diagnosis of FPHL was established through clinical examination and trichoscopy. Inclusion criteria involved patients with no prior treatment within the last year and without any comorbidities. BTA, specifically 100 units, was mixed with 2 mL of 0.9% normal saline. Twenty injection target sites, spaced 2-3 cm apart, were symmetrically marked on the hairless area of the scalp. A dosage of five units was intradermally injected at each target site. Representative photographs and dermoscopic images of the scalp were captured before and after 3 months of treatment. RESULTS: A total of 10 FPHL, aged between 26 and 40 years, were included. The average age was 30.3 ± 4.64 years, and all patients had a positive family history of Androgenetic Alopecia. The average duration of the disease was 3.70 ± 1.42 years. According to patients' self-assessment, after 1 month of treatment, 10 FPHL patients reported experiencing moderate to marked improvement in symptoms related to scalp oil secretion. Three months later, dermatological assessments showed that three had mild improvement, six had no change, and one had a worsening condition. No adverse effects were observed. CONCLUSIONS: Our study suggests that the effectiveness of BTA for FPHL is limited to 3 months. However, it can be considered for tentative use after effective communication with patients. The long-term efficacy and safety of BTA in treating FPHL require further observation and study.


Asunto(s)
Toxinas Botulínicas Tipo A , Minoxidil , Adulto , Femenino , Humanos , Minoxidil/uso terapéutico , Toxinas Botulínicas Tipo A/efectos adversos , Alopecia/tratamiento farmacológico , Cuero Cabelludo
9.
BMC Pulm Med ; 24(1): 173, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609925

RESUMEN

BACKGROUND: Chronic obstructive pulmonary disease (COPD) induced by smoking poses a significant global health challenge. Recent findings highlight the crucial role of extracellular vesicles (EVs) in mediating miRNA regulatory networks across various diseases. This study utilizes the GEO database to uncover distinct expression patterns of miRNAs and mRNAs, offering a comprehensive understanding of the pathogenesis of smoking-induced COPD. This study aims to investigate the mechanisms by which extracellular vesicles (EVs) mediate the molecular network of miR-422a-SPP1 to delay the onset of COPD caused by smoking. METHODS: The smoking-related miRNA chip GSE38974-GPL7723 was obtained from the GEO database, and candidate miRs were retrieved from the Vesiclepedia database. Downstream target genes of the candidate miRs were predicted using mRNA chip GSE38974-GPL4133, TargetScan, miRWalk, and RNA22 databases. This prediction was integrated with COPD-related genes from the GeneCards database, downstream target genes predicted by online databases, and key genes identified in the core module of WGCNA analysis to obtain candidate genes. The candidate genes were subjected to KEGG functional enrichment analysis using the "clusterProfiler" package in R language, and a protein interaction network was constructed. In vitro experiments involved overexpressing miRNA or extracting extracellular vesicles from bronchial epithelial cell-derived exosomes, co-culturing them with myofibroblasts to observe changes in the expression levels of the miR-422a-SPP1-IL-17 A regulatory network, and assessing protein levels of fibroblast differentiation-related factors α-SMA and collagen I using Western blot analysis. RESULTS: The differential gene analysis of chip GSE38974-GPL7723 and the retrieval results from the Vesiclepedia database identified candidate miRs, specifically miR-422a. Subsequently, an intersection was taken among the prediction results from TargetScan, miRWalk, and RNA22 databases, the COPD-related gene retrieval results from GeneCards database, the WGCNA analysis results of chip GSE38974-GPL4133, and the differential gene analysis results. This intersection, combined with KEGG functional enrichment analysis, and protein-protein interaction analysis, led to the final screening of the target gene SPP1 and its upstream regulatory gene miR-422a. KEGG functional enrichment analysis of mRNAs correlated with SPP1 revealed the IL-17 signaling pathway involved. In vitro experiments demonstrated that miR-422a inhibition targets suppressed the expression of SPP1 in myofibroblasts, inhibiting differentiation phenotype. Bronchial epithelial cells, under cigarette smoke extract (CSE) stress, could compensate for myofibroblast differentiation phenotype by altering the content of miR-422a in their Extracellular Vesicles (EVs). CONCLUSION: The differential gene analysis of Chip GSE38974-GPL7723 and the retrieval results from the Vesiclepedia database identified candidate miRs, specifically miR-422a. Further analysis involved the intersection of predictions from TargetScan, miRWalk, and RNA22 databases, gene search on COPD-related genes from the GeneCards database, WGCNA analysis from Chip GSE38974-GPL4133, and differential gene analysis, combined with KEGG functional enrichment analysis and protein interaction analysis. Ultimately, the target gene SPP1 and its upstream regulatory gene miR-422a were selected. KEGG functional enrichment analysis on mRNAs correlated with SPP1 revealed the involvement of the IL-17 signaling pathway. In vitro experiments showed that miR-422a targeted inhibition suppressed the expression of SPP1 in myofibroblast cells, inhibiting differentiation phenotype. Furthermore, bronchial epithelial cells could compensate for myofibroblast differentiation phenotype under cigarette smoke extract (CSE) stress by altering the miR-422a content in their extracellular vesicles (EVs).


Asunto(s)
Vesículas Extracelulares , MicroARNs , Humanos , Vesículas Extracelulares/genética , Interleucina-17/genética , MicroARNs/genética , Osteopontina , Transducción de Señal , Fumar/efectos adversos
10.
Int J Biol Macromol ; 260(Pt 1): 129333, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218279

RESUMEN

Methylesterases (MES) are involved in hydrolysis of carboxylic esters, which have substantial roles in plant metabolic activities and defense mechanisms. This study aimed to comprehensively investigate Brassica napus BnMESs and characterize their role in response to Plasmodiophora brassicae stress. Forty-four BnMES members were identified and categorized into three groups based on their phylogenetic relationships and structural similarities. Through functional predictions in the promoter regions and analysis of RNA-Seq data, BnMES emerged as pivotal in growth, development, and stress responses to B. napus, particularly BnMES34, was strongly induced in response to P. brassicae infection. Gene Ontology analyses highlighted BnMES34's role in regulation of plant disease resistance responses. Furthermore, overexpression of BnMES34 in A. thaliana exhibited milder clubroot symptoms, and reduced disease indices, suggesting positive regulatory role of BnMES34 in plant's response to P. brassicae stress. Molecular docking and enzyme activity verification indicated that BnMES34 has the ability to generate salicylic acid via methyl salicylate, and further experimentally validated in vivo. This discovery indicates that the overexpression of BnMES34 in Arabidopsis confers resistance against clubroot disease. Overall, our research suggests that BnMES34 has a beneficial regulatory role in enhancing stress resistance to P. brassicae in B. napus.


Asunto(s)
Arabidopsis , Plasmodiophorida , Arabidopsis/genética , Arabidopsis/metabolismo , Plasmodiophorida/metabolismo , Filogenia , Simulación del Acoplamiento Molecular , Enfermedades de las Plantas/genética , Ácido Salicílico/metabolismo , Evolución Molecular
11.
J Environ Manage ; 351: 119784, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38081091

RESUMEN

During the long-term stabilization process of landfills, the pressure field undergoes constant changes. This study constructed dynamic pressure changes scenarios of high-pressure differentials (0.6 MPa) and low-pressure differentials (0.2 MPa) in the landfill pressure field at 25 °C and 50 °C, and investigated the sulfate reduction behavior in response to landfill dynamic pressure changes. The results showed that the pressurization or depressurization of high-pressure differentials caused more significant differences in sulfate reduction behavior than that of low-pressure differentials. The lowest hydrogen sulfide (H2S) release peak concentration under pressurization was only 29.67% of that under initial pressure condition; under depressurization, the highest peak concentration of H2S was up to 21,828 mg m-3, posing a serious risk of H2S pollution. Microbial community and correlation analysis showed that pressure had a negative impact on the sulfate-reducing bacteria (SRB) community, and the SRB community adjusted its structure to adapt to pressure changes. Specific SRBs were further enriched with pressure changes. Differential H2S release behavior under pressure changes in the 25 °C pressure environments were mediated by Desulfofarcimen (ASV343) and Desulfosporosinus (ASV1336), while Candidatus Desulforudis (ASV24) and Desulfohalotomaculum (ASV94) played a key role at 50 °C. This study is helpful in the formulation of control strategies for the source of odor pollution in landfills.


Asunto(s)
Desulfovibrio , Sulfuro de Hidrógeno , Sulfuro de Hidrógeno/química , Instalaciones de Eliminación de Residuos , Sulfatos/química
12.
iScience ; 26(11): 108130, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37876795

RESUMEN

Parkinson's disease (PD) is characterized by the irreversible loss of dopaminergic neurons and the accumulation of α-synuclein in Lewy bodies. The oligomeric α-synuclein (O-αS) is the most toxic form of α-synuclein species, and it has been reported to be a robust inflammatory mediator. Mutations in Leucine-Rich Repeat Kinase 2 (LRRK2) are also genetically linked to PD and neuroinflammation. However, how O-αS and LRRK2 interact in glial cells remains unclear. Here, we reported that LRRK2 G2019S mutation, which is one of the most frequent causes of familial PD, enhanced the effects of O-αS on astrocytes both in vivo and in vitro. Meanwhile, inhibition of LRRK2 kinase activity could relieve the inflammatory effects of both LRRK2 G2019S and O-αS. We also demonstrated that nuclear factor κB (NF-κB) pathway might be involved in the neuroinflammatory responses. These findings revealed that inhibition of LRRK2 kinase activity may be a viable strategy for suppressing neuroinflammation in PD.

13.
Waste Manag ; 171: 491-501, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37806157

RESUMEN

The behavior of sulfate reduction, which was the source of hydrogen sulfide (H2S) odor, was investigated under changing pressure and temperature conditions inside landfills. The results showed that the release of H2S and methyl mercaptan (MM) was significantly inhibited at 25 °C and 50 °C under pressure, and the highest H2S and MM concentrations released were only 0.82 %-1.30 % and 1.87 %-4.32 % of atmospheric pressure, respectively. Analysis of the microbial community structure and identification of sulfate-reducing bacteria (SRB) revealed that temperature significantly altered the microbial community in the landfill environment, while pressure inhibited some bacteria and induced the growth and reproduction of specific bacteria. Key SRB (Desulfosporosinus-ASV212, Desulfitibacter-ASV1744) mediated differentiated sulfate reduction behavior in the pressure-bearing environment at 25 °C, while key SRB (Dethiobacter-ASV177, Desulfitibacter-ASV2355 and ASV316) were involved at 50 °C. This study provides a theoretical basis for the formulation of landfill gas management and control strategies.

14.
Plants (Basel) ; 12(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687373

RESUMEN

The leaf is the main site of photosynthesis and is an important component in shaping the ideal rice plant architecture. Research on leaf morphology and development will lay the foundation for high-yield rice breeding. In this study, we isolated and identified a novel curling leaf mutant, designated curling leaf 1 (cl1). The cl1 mutant exhibited an inward curling phenotype because of the defective development of sclerenchymatous cells on the abaxial side. Meanwhile, the cl1 mutant showed significant reductions in grain yield and thousand-grain weight due to abnormal leaf development. Through map-based cloning, we identified the CL1 gene, which encodes a MYB transcription factor that is highly expressed in leaves. Subcellular localization studies confirmed its typical nuclear localization. Transcriptome analysis revealed a significant differential expression of the genes involved in photosynthesis, leaf morphology, yield formation, and hormone metabolism in the cl1 mutant. Yeast two-hybrid assays demonstrated that CL1 interacts with alpha-tubulin protein SRS5 and AP2/ERF protein MFS. These findings provide theoretical foundations for further elucidating the mechanisms of CL1 in regulating leaf morphology and offer genetic resources for practical applications in high-yield rice breeding.

15.
J Agric Food Chem ; 71(33): 12440-12451, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37566096

RESUMEN

Fusarium graminearum, which causes Fusarium head blight (FHB) in cereals, is one of the most devastating fungal diseases by causing great yield losses and mycotoxin contamination. A major bioactive ingredient, venturicidin A (VentA), was isolated from Streptomyces pratensis S10 mycelial extract with an activity-guided approach. No report is available on antifungal activity of VentA against F. graminearum and effects on deoxynivalenol (DON) biosynthesis. Here, VentA showed a high antagonistic activity toward F. graminearum with an EC50 value of 3.69 µg/mL. As observed by scanning electron microscopy, after exposure to VentA, F. graminearum conidia and mycelia appeared abnormal. Different dyes staining revealed that VentA increased cell membrane permeability. In growth chamber and field trials, VentA effectively reduced disease severity of FHB. Moreover, VentA inhibited DON biosynthesis by reducing pyruvic acid, acetyl-CoA production, and accumulation of reactive oxygen species (ROS) and then inhibiting trichothecene (TRI) genes expression and toxisome formation. These results suggest that VentA is a potential fungicide for controlling FHB.


Asunto(s)
Fungicidas Industriales , Fusarium , Micotoxinas , Fungicidas Industriales/farmacología , Fungicidas Industriales/metabolismo , Micotoxinas/metabolismo , Enfermedades de las Plantas/microbiología
16.
J Environ Manage ; 344: 118733, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37562250

RESUMEN

Protection and rectification patters of urban wetlands have been considered in strategies to balance services to society and negative consequences of excess reactive nitrogen (Nr) loading. However, the knowledge about strategies of semi-constructed wetlands on nitrogen (N) cycling pathways and removal Nr from the overlying water is limited. This study aimed to reveal considerable differences among rectification patterns of the typical semi-constructed wetland (Xixi wetland), comprising rational exploitation area (REA), rehabilitation and reconstruction area (RRA), and conservation area (CA) by analyzing the N distribution and N protentional pathways among them. Results pointed out that both NH4+ and NO3- concentration were prominently higher in REA, as opposed to CA and RRA. Sediments in RRA had relatively higher NH4+ content, indicating the efficiency of dissimilatory nitrate reduction (DNRA) in RRA. Moreover, there was a significant shift in the microbial community structure across different sites and sediments. Metagenomic analysis distinguished the N cycling pathways, with nitrification (M00804), denitrification (M00529), and DNRA (M00530) being the crucial pathways in the semi-constructed wetland. The relative abundance of N metabolic pathways (ko00910) varied among different types of sediments, being more abundant in shore and rhizosphere areas and less abundant in bottom sediments. Methylobacter and Nitrospira were the predominant nitrifiers in shore sediments, while Methylocystis was enriched in the bottom sediments and rhizosphere soils. Furthermore, Anaeromyxobacter, Anaerolinea, Dechloromonas, Nocardioides, and Methylocystis were identified as the primary denitrifiers with N reductase genes (nirK, nirS, or nosZ). Among these, Anaeromyxobacter, Dechloromonas, and Methylocystis were the primary contributors containing the nosZ gene in semi-constructed wetlands, driving the conversion of N2O to N2. This study provides important insights into rectification-dependent Nr removal from the overlying water in terms of N distribution and N metabolic functional microbial communities in the semi-constructed wetlands.


Asunto(s)
Desnitrificación , Humedales , Nitrógeno , Nitrificación , Nitratos
17.
Environ Sci Pollut Res Int ; 30(39): 90844-90857, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37464207

RESUMEN

The mechanism of antibiotic resistance (AR) development in an activated sludge system under tetracycline (TC) pressure was discussed and analyzed. According to the variation of macro-factors, including TC, COD, TN, TP, NH3-N, pH, heavy metals, and reactor settings, the tet genes respond accordingly. Consequently, the enrichment sites of tet genes form an invisible AR selection zone, where AR microorganisms thrive, gather, reproduce, and spread. The efflux pump genes tetA and tetB prefer anaerobic environment, while ribosome protective protein genes tetM, tetO, tetQ, tetT, and tetW were more concentrated in aerobic situations. As a corresponding micro-effect, different types of tet genes selected the corresponding dominant bacteria such as Thauera and Arthrobacter, suggesting the intrinsic relationship between tet genes and potential hosts. In summary, the macro-response and micro-effect of tet genes constitute an interactive mechanism with tet genes as the core, which is the crucial cause for the continuous development of AR. This study provides an executable strategy to control the development of AR in actual wastewater treatment plants from the perspective of macro-factors and micro-effects.


Asunto(s)
Genes Bacterianos , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Antibacterianos/farmacología , Tetraciclina/farmacología , Farmacorresistencia Microbiana/genética , Resistencia a la Tetraciclina/genética
18.
Artículo en Inglés | MEDLINE | ID: mdl-37464816

RESUMEN

Aims: Cystathionine ß-synthase (CBS) is essential for homocysteine (Hcy) transsulfuration, yielding cysteine as a common precursor of hydrogen sulfide (H2S), glutathione (GSH), and other sulfur molecules, which produce neuroprotective effects in neurological conditions. We previously reported a disruption of microglial CBS/H2S signaling in a Parkinson's disease (PD) mouse model. Yet, it remains unclear whether CBS affects nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome activity and other pathologies in PD. Results: Microglial CBS expression decreased after lipopolysaccharide (LPS) stimulation. Elevated GSSG (the oxidized GSH) content and decreased H2S generation were found in the brains of microglial cbs conditional-knockout (cbscKO) mice, whereas serum and brain Hcy levels remained unaltered. Moreover, microglial cbscKO mice were susceptible to NLRP3 inflammasome activation and dopaminergic neuron losses caused by LPS injection into the substantia nigra, whereas cbs overexpression or activation produced opposite effects. In vitro studies showed that cbs overexpression or activation suppressed microglial NLRP3 inflammasome activation and interleukin (IL)-1ß secretion by reducing mitochondrial reactive oxygen species (mitoROS) level. Conversely, ablation of cbs enhanced NLRP3 expression and mitoROS generation and augmented microglial NLRP3 inflammasome activity in response to adenosine triphosphate challenge, which was blocked by the mitoROS scavenger. Innovation and Conclusion: The study demonstrated an elevated GSSG level and reduced H2S generation, which correlated with a susceptible status of microglia in the brain of cbscKO mice. Our findings reveal a critical role of CBS in restraining the microglial NLRP3 inflammasome by controlling redox homeostasis and highlight that activation or upregulation of CBS may become a potential strategy for PD treatment.

19.
Waste Manag ; 168: 366-375, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37343443

RESUMEN

Attention should be paid to the As(V) reducing behavior in landfills under different temperature fields. In this study, microcosm tests were conducted using enrichment culture from a landfill. The results revealed that the reduction rate of As(V) was significantly affected by the temperature field, with the highest reduction rate observed at 50 °C, followed by 35 °C, 25 °C, and 10 °C. Different As cycling pathways were observed under various temperature fields. At room and medium temperatures, As4S4 was detected, indicating that both biomineralization and methylation processes occurred after As(V) reduction. However, only biogenic methylation was observed under high or low temperatures, indicating that the viability and adaptability of microorganisms varied depending on the temperature field and As contents. Pseudomonas was found to be the primary genus and dominant As(V) reduction bacteria (ARB) in all reactors. The study revealed that Pseudomonas accounted for a significant proportion of arsC genes, ranging from 87.29% to 97.59%, while arsCs genes were predominantly found in Bacillales and Closestridiales, with a contribution ranging from 89.17% to 96.59%. Interestingly, Bacillus and Clostridium were found to possess arsA genes in their metagenome-ssembled genome, resulting in a higher As(V) reducing rate under medium and high temperatures. These findings underscore the importance of temperature in modulating As(V) reducing behavior and As cycling, and could have implications for managing As pollution in landfill sites.


Asunto(s)
Arseniatos , Arsénico , Arseniatos/metabolismo , Temperatura , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Instalaciones de Eliminación de Residuos
20.
Environ Pollut ; 333: 121981, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37321316

RESUMEN

The environmental behavior of emerging contaminants of microplastics (MPs), antibiotics and antibiotic resistance genes (ARGs) in the leachate activated sludge system has been monitored and analyzed comprehensively. The results suggested that MPs could effectively alter the migration trajectory of tetracycline resistance genes (tet genes) in the leachate activated sludge system under intermittent and continuous influent conditions. After adding MPs, the total average abundance of tet genes in leachate increased from 0.74 ± 0.07 to 0.78 ± 0.07 (log10tet genes/log10 16S rRNA) and that in sludge increased from 0.65 ± 0.08 to 0.70 ± 0.06 (log10tet genes/log10 16S rRNA). Except for tetA, the abundance of tetB, tetO, tetM and tetQ on MPs increased with increasing TC concentration under both aerobic and anaerobic conditions. MPs not only significantly affect the abundance level and migration trajectory of ARGs in the leachate activated sludge system, but also remarkably improve the level of heavy metals in the ambient environment, indirectly promoting the selective effect of antibiotic-resistant bacteria (ARB) and promoting the development of antibiotic resistance (AR). In addition, MPs changed their physicochemical properties and released hazardous substances with aging to force tet genes to migrate from the leachate activated sludge system to the MPs, making AR more difficult to eliminate and persisted in wastewater treatment plants. Meanwhile, microorganisms played a driving role, making MPs serve as a niche for ARGs and ARB colonization. The co-occurrence network analysis indicated the specific distribution pattern of tet genes and microorganisms in different media, and the potential host was speculated. This study improves the understanding of the environmental behavior of emerging contaminants in leachate activated sludge system and lays a theoretical for protecting the ecological environment.


Asunto(s)
Microplásticos , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Plásticos , ARN Ribosómico 16S/genética , Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Genes Bacterianos , Antibacterianos/farmacología , Antibacterianos/análisis , Farmacorresistencia Microbiana/genética
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