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1.
Environ Pollut ; 359: 124591, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39043311

RESUMO

Marine microplastics (MPs) pollution, with rivers as a major source, leads to MPs accumulation in estuarine sediments, which are also nitrogen cycling hotspots. However, the impact of MPs on nitrogen cycling in estuarine sediments has rarely been documented. In this study, we conducted microcosm experiment to investigate the effects of commonly encountered polyethylene (PE) and polystyrene (PS) MPs, with two MPs concentrations (0.3% and 3% wet sediment weight) based on environmental concentration considerations and dose-response effects, on sediment dissolved oxygen (DO) diffusion capacity and microbial communities using microelectrode system and metagenomic analysis respectively. The results indicated that high concentrations of PE-MPs inhibited DO diffusion during the mid-phase of the experiment, an effect that dissipated in the later stages. Metagenomic analysis revealed that MP treatments reduced the relative abundance of dominant microbial colonies in the sediments. The PCoA results demonstrated that MPs altered the microbial community structure, particularly evident under high concentration PE-MPs treatments. Functional analysis related to the nitrogen cycle suggested that PS-MPs promoted the nitrification, denitrification, and DNRA processes, but inhibited the ANRA process, while PE-MPs had an inhibitory effect on the nitrate reduction process and the ANRA process. Additionally, the high concentration of PE-MPs treatment significantly stimulated the abundance of genus (Bacillus) by 34.1% and genes (lip, pnbA) by 100-187.5% associated with plastic degradation, respectively. Overall, in terms of microbial community structure and the abundance of nitrogen cycling functional genes, PE- and PS- MPs exhibit both similarities and differences in their impact on nitrogen cycling. Our findings highlight the complexity of MP effects on nitrogen cycling in estuarine sediments and high concentrations of PE-MP stimulated plastic-degrading genus and genes.

2.
Bioengineering (Basel) ; 11(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39061743

RESUMO

Neutral pullulanases, having a good application prospect in trehalose production, showed a limited expression level. In order to address this issue, two approaches were utilized to enhance the yield of a new neutral pullulanase variant (PulA3E) in B. subtilis. One involved using multiple copies of genome integration to increase its expression level and fermentation stability. The other focused on enhancing the PulA-type atypical secretion pathway to further improve the secretory expression of PulA3E. Several strains with different numbers of genome integrations, ranging from one to four copies, were constructed. The four-copy genome integration strain PD showed the highest extracellular pullulanase activity. Additionally, the integration sites ytxE, ytrF, and trpP were selected based on their ability to enhance the PulA-type atypical secretion pathway. Furthermore, overexpressing the predicated regulatory genes comEA and yvbW of the PulA-type atypical secretion pathway in PD further improved its extracellular expression. Three-liter fermenter scale-up production of PD and PD-ARY yielded extracellular pullulanase activity of 1767.1 U/mL at 54 h and 2465.1 U/mL at 78 h, respectively. Finally, supplementing PulA3E with 40 U/g maltodextrin in the multi-enzyme catalyzed system resulted in the highest trehalose production of 166 g/L and the substrate conversion rate of 83%, indicating its potential for industrial application.

3.
Sci Total Environ ; 947: 174685, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38997042

RESUMO

At present, there has been relatively less coverage of microplastics (MPs) pollution in sediment columns, especially across a large geographical span. This study collected sediment columns across 11 provinces along the coastline of China for MPs pollution investigation. The study found higher MPs diversity (Simpson diversity index) in sediment columns than in surface sediments, mostly comprising fiber MPs with dominant transparent and blue colors. Lower MPs pollution was noted in mangrove reserves, while estuarine and coastal areas showed higher pollution levels. Spearman correlation analysis shows that vertical of MPs abundance significantly decreased with depth at 6 of 11 sites. Large-sized MPs with diverse colors in deeper sediments (>40 cm) suggests that burial processes may render MPs more resistant to degradation. Our research highlights varied MPs distribution in coastal sediment, aiding future marine MPs pollution prediction and assessment.

4.
Microorganisms ; 12(7)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39065044

RESUMO

The N-terminal sequences of proteins and their corresponding encoding sequences may play crucial roles in the heterologous expression. In this study, the secretory expression of alkaline pectin lyase APL in B. subtilis was investigated to explore the effects of the N-terminal 5-7 amino acid sequences of different signal peptides on the protein expression and secretion. It was identified for the first time that the first five amino acid sequences of the N-terminal of the signal peptide (SP-LipA) from Bacillus subtilis lipase A play an important role in promoting the expression of APL. Furthermore, it was revealed that SP-LipA resulted in higher secretory expression compared to other signal peptides in this study primarily due to its encoding of N-terminal amino acids with relatively higher transcription levels and its efficient secretion capacity. Based on this foundation, the recombinant strain constructed in this work achieved a new record for the highest extracellular yields of APL in B. subtilis, reaching 12,295 U/mL, which was 1.9-times higher than that expressed in the recombinant Escherichia coli strain previously reported. The novel theories uncovered in this study are expected to play significant roles in enhancing the expression of foreign proteins both inside and outside of cells.

5.
Sci Rep ; 14(1): 13401, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862526

RESUMO

This study aimed to determine an immune-related RNA signature as a prognostic marker, in this study, we developed a risk score model for predicting the prognosis of osteosarcoma metastasis. We first downloaded the clinical information and expression data of osteosarcoma samples from the UCSC Xena and GEO databases, of which the former was the training set and the latter was the validation set. Immune infiltration was assessed using the ssGSEA and ESTIMATE algorithms, and the osteosarcoma samples were divided into the Immunity_L and Immunity_H groups. Then, eleven RNAs were identified as the optimal prognostic RNA signatures using LASSO Cox regression analysis for establishing a risk score (RS) model. Kaplan-Meier approach indicated the high-risk group exhibited a shorter survival. Furthermore, we analyzed the tumor metastasis, age, and RS model status were determined to be independent clinical prognostic factors using Cox regression analysis. Decision curve analysis (DCA) indicated that the prognostic factor + RS model had the best net benefit. Finally, nine tumor-infiltrating immune cells (TIICs) showed significant differences in abundance between high- and low-risk groups via CIBERSORT deconvolution algorithm. In conclusion, the immune-related eleven-RNA signature be could served as a potential prognostic biomarker for osteosarcoma metastasis.


Assuntos
Biomarcadores Tumorais , Neoplasias Ósseas , Osteossarcoma , Osteossarcoma/genética , Osteossarcoma/imunologia , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Humanos , Prognóstico , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/patologia , Biomarcadores Tumorais/genética , Feminino , Masculino , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica , Estimativa de Kaplan-Meier , Perfilação da Expressão Gênica , Transcriptoma , Modelos de Riscos Proporcionais , Fatores de Risco , Algoritmos
6.
J Hazard Mater ; 475: 134769, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38870849

RESUMO

Microplastics (MPs) are widely distributed in the sea, but the vertical transfer of MPs by marine organisms in coastal area is still poorly understood. In this study, we used laser direct infrared (LDIR) spectroscopy to determine the number and characteristics of MPs deposited by cultured oyster Crassostrea gigas and further compared the differences between MPs of natural deposit and biodeposit in field environments. The amounts of MPs found in the biodeposit of cultured oysters were 3.54 times greater than that in the natural deposition. The polymer types of biodeposit MPs also differed from those of natural deposition. It was estimated that a single oyster can deposit 15.88 MPs per day, which is a figure much higher than the initial results, and hotspots of MPs deposition may be formed within the oyster aquaculture area. We used generalized linear mixed model (GLMM) to further infer the sources of MPs in sediments and found that distance to shore, cultured zone and urban center were important predictors of MPs abundance in sediments of aquaculture area. The above results suggest that cultured bivalves have an important capacity for MPs biodeposition and will further change the vertical distribution pattern of MPs in coastal environments.


Assuntos
Aquicultura , Crassostrea , Microplásticos , Poluentes Químicos da Água , Animais , Microplásticos/análise , Poluentes Químicos da Água/análise , Crassostrea/metabolismo , Monitoramento Ambiental , Sedimentos Geológicos/química , Água do Mar/química
7.
Aquat Toxicol ; 272: 106959, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768528

RESUMO

As one of the main components of marine pollution, microplastics (MPs) inevitably enter the mussel aquaculture environment. At the same time, pathogenic bacteria, especially pathogens such as Vibrio, can cause illness outbreaks, leading to large-scale death of mussels. The potential harm of MPs and pathogenic bacteria to bivalve remains unclear. This study designed two experiments (1) mussels (Mytilus galloprovincialis) were exposed to 100 particles/L or 1,000 particles/L polymethyl methacrylate (PMMA, 17.01 ± 6.74 µm) MPs and 1 × 107 CFU/mL Vibrio parahaemolyticus at the same time (14 days), and (2) mussels were exposed to 100 particles/L or 1,000 particles/L MPs for a long time (30 days) and then exposed to 1 × 107 CFU/mL V. parahaemolyticus to explore the effects of these two stresses on the mussel immune system. The results showed that after the combined exposure of V. parahaemolyticus and MPs, the lysosomal membrane stability of hemocytes decreased, lysozyme activity was inhibited, and hemocytes were induced to produce more lectins and defensins to fight pathogenic invasion. Long-term exposure to MPs caused a large amount of energy consumption in mussels, inhibited most of the functions of humoral immunity, increased the risk of mussel infection with pathogenic bacteria, and negatively affected mussel condition factor, the number of hemocytes, and the number of byssuses. Mussels may allocate more energy to deal with MPs and pathogenic bacterial infections rather than for growth. Above all, MPs exposure can affect mussel immune function or reduce its stress resistance, which in turn has an impact on mollusk farming.


Assuntos
Hemócitos , Microplásticos , Mytilus , Vibrio parahaemolyticus , Poluentes Químicos da Água , Animais , Mytilus/microbiologia , Mytilus/efeitos dos fármacos , Mytilus/imunologia , Microplásticos/toxicidade , Vibrio parahaemolyticus/fisiologia , Vibrio parahaemolyticus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Hemócitos/efeitos dos fármacos , Hemócitos/imunologia , Muramidase/metabolismo , Sistema Imunitário/efeitos dos fármacos
8.
Mar Environ Res ; 196: 106434, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460223

RESUMO

The adverse impacts of microplastics (MPs) or ocean acidification (OA) on mollusks have been widely reported, however, little is known about their combined effects on mollusks. The oysters Crassostrea gigas were exposed to two sizes of polystyrene MPs with 1 × 104 particles/L (small polystyrene MPs (SPS-MPs): 6 µm, large polystyrene MPs (LPS-MPs): 50-60 µm) at two pH levels (7.7 and 8.1) for 14 days. The antagonistic effects between MPs and OA on oysters were mainly observed. Single SPS-MPs exposure can induce CAT enzyme activity and LPO level in gills, while LPS-MPs exposure alone can increase PGK and PEPCK gene expression in digestive glands. Ocean acidification can increase clearance rate and inhibit antioxidant enzyme activity, whereas combined exposure of OA and SPS-MPs can affect the metabolomic profile of digestive glands. This study emphasized that the potential toxic effects of MPs under the scene of climate change should be concerned.


Assuntos
Crassostrea , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Crassostrea/metabolismo , Poliestirenos/toxicidade , Plásticos , Água do Mar , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Poluentes Químicos da Água/metabolismo , Antioxidantes , Biomarcadores/metabolismo
9.
Mar Pollut Bull ; 200: 116151, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38359480

RESUMO

Microplastics (MPs) pollution's impact on the marine ecosystem is widely recognized. This study compared the effects of polyethylene (PE) and polyethylene terephthalate (PET) on two bivalve species, Ruditapes philippinarum (clam) and Chlamys farreri (scallop), at two particle concentrations (10 and 1000 µg/L). MPs were found in the digestive glands and gills of both species. Although clearance rates showed no significant changes, exposure to different MPs caused oxidative stress, energy disruption, and lipid metabolism disorders in both clam and scallop. Histopathological damage was observed in gills and digestive glands. IBR values indicated increasing toxicity with concentration, with PET being more toxic than PE. WOE model suggested increasing hazard with concentration, highlighting higher PET toxicity on clam digestive glands. In contrast, PE hazard increased in gills, showing different species responses. R. philippinarum exhibited higher sensitivity to MPs than C. farreri, providing insights for assessing ecological risk under realistic conditions and stress conditions.


Assuntos
Bivalves , Pectinidae , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Plásticos/metabolismo , Ecossistema , Polietilenotereftalatos , Polietileno/metabolismo , Poluentes Químicos da Água/análise
10.
Sci Total Environ ; 913: 169739, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38163610

RESUMO

Microplastics (MPs) pollution in the marine environment has become a global problem. In this study, a number of 21 mollusk species (n = 2006) with different feeding habits were collected from 11 sites along the Bohai Sea for MPs uptake analysis. The MPs in mollusk samples were isolated and identified by micro-Fourier Transform Infrared Spectroscopy (µ-FTIR), and an assessment of the health risks of MPs ingested by mollusk consumption is also conducted. Approximately 91.9 % of the individuals among all the collected species inhaled MPs, and there was an average abundance of 3.30 ± 2.04 items·individual-1 or 1.04 ± 0.74 items·g-1 of wet weight. The shape of MPs was mainly fiber, and a total number of 8 polymers were detected, of which rayon had the highest detection rate (58.3 %). The highest abundance, uptake rate and polymer composition of MPs was observed in creeping types, suggesting that they might ingest these MPs from their food. The gastropod Siphonalia subdilatata contains the highest levels of MPs, which may increase the risk of human exposure if consumed whole without removing the digestive gland. The polymer risk level of MPs in these mollusks was Level III (H = 299), presenting harmful MPs such as polyvinyl chloride. In terms of human exposure risk, the average risk of human exposure to MPs through consumption of Bohai mollusks is estimated to be 3399 items·(capita·year)-1 (424-9349 items·(capita·year)-1). Overall, this study provides a basis for the ecological and health Risk assessment of MPs in mollusks collected from the coastline of China.


Assuntos
Gastrópodes , Poluentes Químicos da Água , Humanos , Animais , Microplásticos/análise , Plásticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Moluscos , Medição de Risco
11.
Sci Rep ; 13(1): 18393, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884572

RESUMO

Sexism is a widespread form of gender discrimination, which can take the form of criticism towards women based on gender stereotypes. However, little is known about how perceived criticism and sexism shape one's construal of criticism from various interpersonal sources. The present study investigated whether perceived criticism, perceived sexism and the source of criticism (mother, father, workplace supervisor, romantic partner) interact to influence upset levels in response to criticism. 178 participants completed perceived criticism (PC) ratings for the four relationships and 95 female participants also completed the Schedule of Sexist Events scale. Participants read experimental vignettes describing scenarios of criticism from different sources and rated how upset they would feel in each scenario. Perceived sexism significantly moderated the effect of PC on upset levels only for sexist-related criticism from romantic partners and supervisors. Female participants with low perceived sexism show higher levels of upset as PC increased for sexist-related criticism from supervisors whereas female participants with high perceived sexism show lower levels of upset as PC increased for sexist-related criticism from romantic partners. These findings contribute towards understanding how perceived criticism and perceived sexism influence affective reactions to criticism across interpersonal sources.


Assuntos
Relações Interpessoais , Sexismo , Humanos , Feminino , Sexismo/psicologia , Emoções , Mães
12.
Cell Rep Med ; 4(10): 101222, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37794586

RESUMO

Sporadic synchronous colorectal cancer (SCRC) refers to multiple primary CRC tumors detected simultaneously in an individual without predisposing hereditary conditions, which accounts for the majority of multiple CRCs while lacking a profound understanding of the genomic landscape and evolutionary dynamics to optimize its treatment. In this study, 103 primary tumor samples from 51 patients with SCRC undergo whole-exome sequencing. The germline and somatic mutations and evolutionary and clinical features are comprehensively investigated. Somatic genetic events are largely inconsistent between paired tumors. Compared with solitary CRC, SCRCs have higher prevalence of tumor mutation burden high (TMB-H; 33.3%) and microsatellite-instability high (MSI-H; 29.4%) and different mutation frequencies in oncogenic signaling pathways. Moreover, neutrally evolving SCRC tumors are associated with higher intratumoral heterogeneity and better prognosis. These findings unveil special molecular features, carcinogenesis, and prognosis of sporadic SCRC. Strategies for targeted therapy and immunotherapy should be optimized accordingly.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Instabilidade de Microssatélites , Prognóstico , Biomarcadores Tumorais/genética , Genômica
13.
Chemosphere ; 344: 140420, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37838033

RESUMO

Microorganisms can attach on the surface of microplastics (MPs) through biological fouling process to form a diverse community called the "plastisphere", which has attracted extensive attention. Although the microbial structure and composition of biofilm have been studied, the knowledge of its microbial function and ecological risk is still limited. In this study, we investigated how the surface properties of MPs affect the biofilm communities and metabolic features under different environmental conditions, and explored the biofilm enrichment of antibiotic resistance genes (ARGs). The results showed that the incubation time, habitat and MPs aging state significantly influenced the structure and composition of biofilm microbial communities, and a small amount of pathogens have been found in the MPs-attached biofilm. The microbial carbon utilization capacity of the biofilm in different incubation habitats varies greatly with highest metabolism capacity appear in the river. The utilization efficiency of different carbon sources is polymer > carbohydrate > amino acid > carboxylic acids > amine/amide, which indicates that the biofilm communities have selectivity between different types of carbon sources. More importantly, ARGs were detected in all the MPs samples and showed a trend of estuary > river > marine. The aged MPs can accumulate more ARGs than the virgin items. In general, MPs in the aquatic environment may become a carrier for pathogens and ARGs to spread to other environment, which may enhance their potential risks to the ecosystem and human health.


Assuntos
Microbiota , Plásticos , Humanos , Idoso , Antibacterianos/farmacologia , Microplásticos , Genes Bacterianos , Resistência Microbiana a Medicamentos/genética , Carbono
14.
Mar Pollut Bull ; 193: 115153, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37327720

RESUMO

Microplastics (MPs) pollution and salinity variation are two environmental stressors, but their combined effects on marine mollusks are rarely known. Oysters (Crassostrea gigas) were exposed to 1 × 104 particles L-1 spherical polystyrene MPs (PS-MPs) of different sizes (small polystyrene MPs (SPS-MPs): 6 µm, large polystyrene MPs (LPS-MPs): 50-60 µm) under three salinity levels (21, 26, and 31 psu) for 14 days. Results demonstrated that low salinity reduced PS-MPs uptake in oysters. Antagonistic interactions between PS-MPs and low salinity mainly occurred, and partial synergistic effects were mainly induced by SPS-MPs. SPS-MPs induced higher lipid peroxidation (LPO) levels than LPS-MPs. In digestive glands, low salinity decreased LPO levels and glycometabolism-related gene expression, which was related to salinity levels. Low salinity instead of MPs mainly affected metabolomics profiles of gills through energy metabolism and osmotic adjustment pathway. In conclusion, oysters can adapt to combined stressors through energy and antioxidative regulation.


Assuntos
Crassostrea , Poluentes Químicos da Água , Animais , Microplásticos , Poliestirenos/metabolismo , Plásticos/metabolismo , Salinidade , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Estresse Oxidativo , Metabolismo Energético , Poluentes Químicos da Água/metabolismo
15.
J Water Health ; 21(6): 676-686, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37387335

RESUMO

Industrial heavy metal-contaminated wastewater is one of the main water pollution problems. Adsorbents are a promising method for the removal of heavy metal contaminants. Herein, polyaspartic acid/carboxymethyl poplar sawdust hydrogels (PASP/CMPP) and ascorbic acid/carboxymethyl poplar sawdust hydrogels (VC/CMPP) were prepared by aqueous polymerization using alkalized poplar sawdust (CMPP) as the substrate and PASP and vitamin C (VC) as modifiers. The effective results, provided by the characterization analysis of SEM and BET, indicate that the surface of the PASP/CMPP hydrogel has a larger number of loose pores and a larger pore volume than the VC/CMPP hydrogel. The treatment effects of the two hydrogels on simulated wastewater containing Cd(II) were investigated by a batch of experiments. The results showed that PASP/CMPP had a better adsorption effect than VC/CMPP under the same adsorption conditions. Interestingly, the solid concentration effect was found in the process of sorption kinetics and sorption isotherms. The sorption kinetic curves of Cd(II) on PASP/CMPP were well-fitted by the quasi-second-order kinetics under different adsorbent concentrations. The adsorption conforms to Langmuir and Freundlich adsorption isotherm models. More importantly, PASP/CMPP composites are expected to be used as a new kind of environmental adsorbent for wastewater treatment.


Assuntos
Cádmio , Águas Residuárias , Ácido Ascórbico , Celulose , Hidrogéis
16.
Brain Sci ; 13(4)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37190494

RESUMO

Sexism is a widespread form of gender discrimination which includes remarks based on gender stereotypes. However, little is known about the neural basis underlying the experience of sexist-related comments and how perceptions of sexism are related to these neural processes. The present study investigated whether perceptions of sexism influence neural processing of receiving sexist-related comments. Participants (N = 67) read experimental vignettes describing scenarios of comments involving gender stereotypes while near-infrared spectroscopy recordings were made to measure the hemodynamic changes in the prefrontal cortex. Results found a significant correlation between participants' perceptions of sexism and brain activation in a brain cluster including the right dorsolateral prefrontal cortex and inferior frontal gyrus. There was a significant gender difference where female participants showed a stronger negative correlation compared to male participants. Future research can expand on these initial findings by looking at subcortical structures involved in emotional processing and gender stereotype application as well as examining cultural differences in perceptions of gender stereotypes and sexism.

17.
Chemosphere ; 325: 138381, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36907490

RESUMO

Microplastics (MPs) are widely distributed in marine environments, and they are easily attached by various microorganisms, including pathogenic bacteria. When bivalves mistakenly eat MPs, pathogenic bacteria attached to MPs enter their bodies through the Trojan horse effect, causing adverse effects. In this study, the mussel Mytilus galloprovincialis was exposed to aged polymethylmethacrylate MPs (PMMA-MPs, 20 µm) and Vibrio parahaemolyticus attached to PMMA-MPs to explore the effect of synergistic exposure by measuring lysosomal membrane stability, ROS content, phagocytosis, apoptosis in hemocytes, antioxidative enzyme activities and apoptosis-related gene expression in gills and digestive glands. The results showed that MP exposure alone did not cause significant oxidative stress in mussels, but after long-term coexposure to MPs and V. parahaemolyticus, the activities of antioxidant enzymes were significantly inhibited in the gills of mussels. Both single MP exposure and coexposure will affect hemocyte function. Coexposure can induce hemocytes to produce higher ROS, improve phagocytosis, significantly reduce the stability of the lysosome membrane, and induce the expression of apoptosis-related genes, causing apoptosis of hemocytes compared with single MP exposure. Our results demonstrate that MPs attached to pathogenic bacteria have stronger toxic effects on mussels, which also suggests that MPs with pathogenic bacteria might have an influence on the immune system and cause disease in mollusks. Thus, MPs may mediate the transmission of pathogens in marine environments, posing a threat to marine animals and human health. This study provides a scientific basis for the ecological risk assessment of MP pollution in marine environments.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Humanos , Idoso , Mytilus/metabolismo , Microplásticos/toxicidade , Microplásticos/metabolismo , Plásticos/metabolismo , Antioxidantes/metabolismo , Hemócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Polimetil Metacrilato/metabolismo , Polimetil Metacrilato/farmacologia , Poluentes Químicos da Água/análise
18.
Sci Total Environ ; 878: 162977, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36963689

RESUMO

Microplastics (MPs) entering the environment undergo complex weathering (aging) processes, however, the impacts of aged MPs on estuarine nitrogen cycling and microbial ecosystems remain largely unknown. In this study, a 50 days microcosm experiment was conducted to investigate the response of sedimentary nitrogen (N) transformation processes, N2O emission and microbial communities to virgin and aged MPs (PE and PS) exposure. We found that aged MPs influenced sediment nitrogen turnover more rapidly and profoundly than virgin MPs and showed type and dose-response effect. During the first 10 days, higher concentration (3 % by weight of sediment) aged MPs (both PS and PE) treatments significantly promoted denitrification (ANOVA, P < 0.05), while virgin MPs treatments had weak effect on denitrification, compared with the control (P > 0.05). Moreover, higher concentration aged PS-MPs remarkably enhanced N2O emission on the 10th day, while N2O was consumed in the control. After 50 days incubation, there was an overall increase in nirK gene abundance exposed to MPs, and nosZ gene copies in aged PS treatments were around twice that in the control based on qPCR (P < 0.05). The function prediction also showed significant elevation of relative abundance of denitrification and DNRA relevant genes in bacterial community. In addition, aged PS treatment (3 %) recruited specific bacterial and archaeal assemblies, with Sedimenticolaceae, Lentimicrobiaceae, SCGC_AAA011-D5, SG8-5, Lokiarchaeia, and Odinarchaeia selectively enriched in the treatment. Our study highlighted that virgin and aged MPs had different impact on sediment nitrogen cycling, and the ecological risks of aged MPs should be concerned since all MPs eventually get weathered when they enter the environment.


Assuntos
Ecossistema , Microplásticos , Ciclo do Nitrogênio , Microbiologia do Solo , Poluentes Químicos da Água , Bactérias , Desnitrificação , Estuários , Microplásticos/toxicidade , Nitrogênio/análise , Óxido Nitroso/análise , Plásticos , Solo , Ciclo do Nitrogênio/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
19.
Sci Total Environ ; 870: 161893, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36731545

RESUMO

There have been numerous studies that have identified the presence of low-density microplastics (MPs) in the water column and sediments. The focus of current MPs research has shifted towards the interaction of MPs with marine organisms and their potential hazards, including the uptake characteristics, biological transport and toxicological effects of MPs, but the processes involved in the deposition behavior of MPs are still poorly understood. In this review, we summarize the current state of knowledge on the vertical transport of MPs influenced by their physicochemical properties and marine organisms, and discuss their potential impact on MPs deposition. The physicochemical properties of MPs determine their initial distribution. The density, shape, and size of MPs influence their settling state in the marine environment. Marine biota play a key role in the transport of MPs to deep marine environment, mainly by changing the density and adsorption of MPs. Biofouling can alter the surface properties of MPs and increase the overall density, thus affecting the vertical flux of the plastic. Macroalgae may trap MPs particles by producing chemicals or by using electrostatic interactions. Marine swimming organisms ingest MPs and excrete them encapsulated in fecal particles, while the activity of marine benthic organisms may contribute to the transfer of MPs from surface sediments to deeper layers. In addition, MPs may be incorporated into organic particles produced by marine organisms such as marine snow or marine aggregates, increasing the vertical flux of MPs. However, due to the complexity of different sea areas and MPs properties, the deposition behavior of MPs may be the result of the interaction of multiple factors. Thus, the effects of MPs properties, marine organisms and the natural environment on MPs deposition in marine environment needs further research to fill this gap.


Assuntos
Microplásticos , Poluentes Químicos da Água , Microplásticos/química , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Organismos Aquáticos
20.
Acta Pharmacol Sin ; 44(7): 1404-1415, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36721008

RESUMO

Myokines, which are recently identified cytokines secreted by skeletal muscle in response to stimulation, are crucial for the maintenance of liver function. Fulminant hepatitis (FH) is a life-threatening pathological condition with severe hepatic dysfunction. In this study, we investigated the role of meteorin-like (METRNL), a new myokine, in the pathogenesis of FH. We compared serum samples and liver tissues from FH patients and healthy controls and found that hepatic and serum METRNL levels were significantly increased in FH patients, and serum METRNL levels were related to disease severity in FH patients. We then established a concanavalin A-induced FH model in METRNL-overexpressing and control mice. We found that hepatic METRNL levels in FH mice were significantly increased, and METRNL in the liver was mainly derived from macrophages. In the cultured mouse macrophage line (RAW264.7 cells) and mouse primary peritoneal macrophages (PMs), METRNL overexpression significantly inhibited the release of the proinflammatory cytokines TNF and IL-1ß. In METRNL-overexpressing mice, concanavalin A-induced liver injury was significantly ameliorated. Moreover, METRNL overexpression significantly reduced chemokine-dependent inflammatory cell infiltration into the liver. METRNL overexpression also suppressed liver CD4+ T cell differentiation into Th 1 cells and inhibited the secretion of Th 1 cytokines. Taken together, these data suggest that METRNL overexpression effectively ameliorates FH. Therefore, METRNL may serve as a potential biomarker and therapeutic target for FH.


Assuntos
Necrose Hepática Massiva , Camundongos , Animais , Concanavalina A , Quimiocinas , Citocinas/metabolismo
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