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1.
Chemosphere ; 248: 126065, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32045975

RESUMO

Two isoforms of Glutathione S-Transferase (GST) genes, belonging to mu (Dp-GSTm1 and Dp-GSTm2) and sigma (Dp-GSTs1 and Dp-GSTs2) classes, were cloned and characterised in the freshwater Daphnia pulex. No signal peptide was found in any of the four GST proteins, indicating that they were cytosolic GST. A highly conserved glutathione (GSH) binding site (G-site) occurred in the N-terminal sequence, and a substrate binding site (H-site), interacting non-specifically with the second hydrophobic substrate, was present in the C-terminal. A Tyr residue, for the stabilization of GSH, was found to be conserved in the analysed sequences. The secondary and tertiary structures indicated that these genes possess the typical cytosolic GST structure, including a conserved N-terminal domain with a ßαßαßßα motif. The µ loop (NVGPAPDYDR and NFIGAEWDR in Dp-GSTm1 and Dp-GSTm2, respectively) was identified between the ßαß (ß1α1ß2) and αßßα motifs (α2ß3ß4α3) in the N-terminal domain. The expressions of Dp-GSTs1, Dp-GSTs2, and Dp-GSTm1 were higher in other age groups compared to the newly-born neonates (1 d); however, the expression of Dp-GSTm2 first increased and then decreased with age. Gene expression was significantly reduced by high concentration (1 and 2 mg/L) of 75 nm polystyrene nanoplastic. However, nanoplastic exposure at the predicted environmental concentration (1 µg/L) had a low effect. Exposure of mothers to nanoplastic (1 µg/L) elevated the Dp-GSTs2 level in their neonates. These results improve our understanding on the response of different types of Daphnid GST to environmental contaminants, especially nanoplastic.

2.
Aquat Toxicol ; 220: 105420, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31986404

RESUMO

Recently, research on the biological effects of nanoplastics has grown exponentially. However, studies on the effects of nanoplastics on freshwater organisms and the mechanisms of the biological effects of nanoplastics are limited. In this study, the content of reactive oxygen species (ROS), gene and protein expression in the MAPK-HIF-1/NFkB pathway, and antioxidant gene expressions and enzyme activities were measured in Daphnia pulex exposed to polystyrene nanoplastic. In addition, the full-length extracellular signal-regulated kinases (ERK) gene, which plays an important role in the MAPK pathway, was cloned in D. pulex, and the amino acid sequence, function domain, and phylogenetic tree were analyzed. The results show that nanoplastic caused the overproduction of ROS along with other dose-dependent effects. Low nanoplastic concentrations (0.1 and/or 0.5 mg/L) significantly increased the expressions of genes of the MAPK pathway (ERK; p38 mitogen-activated protein kinases, p38; c-Jun amino-terminal kinases, JNK; and protein kinase B, AKT), HIF-1 pathway (prolyl hydroxylasedomain, PHD; vascular endothelial growth factor, VEGF; glucose transporter, GLUT; pyruvate kinase M, PKM; hypoxia-inducible factor 1, HIF1), and CuZn superoxide dismutase (SOD) along with the activity of glutathione-S-transferase. As the nanoplastic concentration increased, these indicators were significantly suppressed. The protein expression ratio of ERK, JNK, AKT, HIF1α, and NFkBp65 (nuclear transcription factor-kB p65) as well as the phosphorylation of ERK and NFkBp65 were increased in a dose-dependent manner. The activities of other antioxidant enzymes (catalase, total SOD, and CuZn SOD) were significantly decreased upon exposure to nanoplastic. Combined with our previous work, these results suggest that polystyrene nanoplastic causes the overproduction of ROS and activates the downstream pathway, resulting in inhibited growth, development, and reproduction. The present study fosters a better understanding of the biological effects of nanoplastics on zooplankton.

3.
Environ Pollut ; 256: 113506, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706756

RESUMO

The biological effects of nanoplastics are a growing concern. However, most studies have focused on exposure to high concentrations or short-term exposure. The potential effects of exposure to low environmental nanoplastic concentrations over the long-term and across multiple generations remain unclear. In the present study, Daphnia pulex was exposed over three 21-day generations to a typical environmental nanoplastic concentration (1 µg/L) and the effects were investigated at physiological (growth and reproduction), gene transcription and enzyme activity levels. Chronic exposure did not affect the survival or body length of D. pulex, whereas the growth rate and reproduction were influenced in the F2 generation. Molecular responses indicated that environmental nanoplastic concentrations can modulate the response of antioxidant defenses, vitellogenin synthesis, development, and energy production in the F0-F1 generations, and prolongation resulted in inhibitory effects on antioxidant responses in F2 individuals. Some recovery was observed in the recovery group, but reproduction and stress defenses were significantly induced. Taken together, these results suggest that D. pulex recovery from chronic exposure to nanoplastic may take several generations, and that nanoplastics have potent long-term toxic effects on D. pulex. The findings highlight the importance of multigenerational and chronic biological evaluations to assess risks of emerging pollution.

4.
Water Environ Res ; 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833589

RESUMO

Nitrate in the effluent of wastewater treatment plants (WWTPs) is the main nitrogen resource in natural water. The excessive nitrogen in natural water causes ecological issues such as aqueous eutrophication. A novel modified NaY zeolite (SMZ-La) with hexadecyl trimethyl ammonium bromide (HDTMA) and lanthanum (La) as modifying agents for NO 3 - -N adsorption was investigated in this study. Results showed that SMZ-La had a higher adsorption capacity (3.82 mg NO 3 - -N/g) than zeolite only modified with HDTMA or La (2.75 and 2.23 mg NO 3 - -N/g, respectively). Moreover, the adsorption process was endothermic with a maximum theoretic adsorption of 14.49 mg NO 3 - -N/g. X-ray photoelectron spectroscopy (XPS) analysis indicated that adsorption rate principally depended on chemisorption between SMZ and NO 3 - -N. Thermogravimetric analysis showed that HDTMA was loaded on the surface of NaY zeolite with double layer. Scanning electron microscope and X-ray spectroscopy analysis illustrated that La was primarily loaded in the pore of NaY zeolite, and the loading of HDTMA and La did not affect the original crystal structure of NaY zeolite. The novel adsorbent provided a promising perspective for nitrogen control in WWTPs and natural water. PRACTITIONER POINTS: A novel modified zeolite (SMZ-La) was prepared successfully with HDTMA and La. SMZ-La had an excellent adsorption capacity compared to SMZ and NaY-La. There were both physical and chemical adsorptions in the adsorption process of SMZ-La on NO 3 - -N.

5.
Environ Pollut ; : 113676, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31818614

RESUMO

CH4 oxidation in landfill cover soils plays a significant role in mitigating CH4 release to the atmosphere. Oxygen availability and the presence of co-contaminants are potentially important factors affecting CH4 oxidation rate and the fate of CH4-derived carbon. In this study, microbial populations that oxidize CH4 and the subsequent conversion of CH4-derived carbon into CO2, soil organic C and biomass C were investigated in landfill cover soils at two O2 tensions, i.e., O2 concentrations of 21% ("sufficient") and 2.5% ("limited") with and without toluene. CH4-derived carbon was primarily converted into CO2 and soil organic C in the landfill cover soils, accounting for more than 80% of CH4 oxidized. Under the O2-sufficient condition, 52.9%-59.6% of CH4-derived carbon was converted into CO2 (CECO2-C), and 29.1%-39.3% was converted into soil organic C (CEorganic-C). A higher CEorganic-C and lower CECO2-C occurred in the O2-limited environment, relative to the O2-sufficient condition. With the addition of toluene, the carbon conversion efficiency of CH4 into biomass C and organic C increased slightly, especially in the O2-limited environment. A more complex microbial network was involved in CH4 assimilation in the O2-limited environment than under the O2-sufficient condition. DNA-based stable isotope probing of the community with 13CH4 revealed that Methylocaldum and Methylosarcina had a higher relative growth rate than other type I methanotrophs in the landfill cover soils, especially at the low O2 concentration, while Methylosinus was more abundant in the treatment with both the high O2 concentration and toluene. These results indicated that O2-limited environments could prompt more CH4-derived carbon to be deposited into soils in the form of biomass C and organic C, thereby enhancing the contribution of CH4-derived carbon to soil community biomass and functionality of landfill cover soils (i.e. reduction of CO2 emission).

6.
Aquat Toxicol ; 217: 105350, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31730932

RESUMO

Cytochrome P450 (CYP) enzymes are one of the largest protein families, and they metabolise a wide range of lipophilic organic endogenous and exogenous compounds. Many cytochrome P450 genes have been cloned and characterised, and they are frequently used as biomarkers in environmental toxicology studies because of their sensitivity and inducibility. In the present study, the full-length cDNAs of DpCYP370B and DpCYP4 were cloned from Daphnia pulex for the first time. The sequence of DpCYP370B consisted of an ORF of 1515 bp that encoded a 504 amino acid polypeptide, while the sequence of DpCYP4 comprised an ORF of 1527 bp that encoded a 508 amino acid polypeptide. Homologous alignments revealed the presence of a conserved cysteine haeme-iron ligand signature, FxxGxxxCxG, located in the C-terminal portion. Both the proteins contained a sequence for a transmembrane region that was deduced to be located in the endoplasmic reticulum. Subsequently, the expression levels of DpCYP370B and DpCYP4, as well as those of CYP4AN1, CYP4C33, and CYP4C34, were investigated using quantitative real-time PCR after exposure to five polystyrene nanoplastic concentrations: 0 (control), 0.1, 0.5, 1, and 2 mg/L for 21 days. Except for DpCYP4, the highest mRNA expression was observed at 0.5 mg/L nanoplastics; next, the expression of three of the enzymes (DpCYP370B, CYP4AN1, CYP4C34,) decreased to that of the control level at 1 and 2 mg/L doses of nanoplastics. The expression of DpCYP4 did not significantly change compared with that of the control group. These results indicated that CYP genes might play an important role in protecting D. pulex against nanoplastic pollutants.

7.
J Therm Biol ; 85: 102404, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31657746

RESUMO

The red claw crayfish, Cherax quadricarinatus, is an economically important freshwater crustacean that cannot tolerate low temperature, which diminishes survival via unknown mechanisms. Herein, physiological regulation of C. quadricarinatus was investigated following exposure to low temperature stress at 9 ±â€¯2 °C for 4 weeks. Hepatopancreas tissue was tested for nonspecific enzyme activity, histological structure, and transcriptome sequencing analyses. The results showed that the activities of nonspecific enzymes were inhibited following low temperature stress. Ultrastructural observation revealed that the hepatopancreas structure was oxidatively damaged at low temperature, with numerous autophagic vesicles visible. Apoptosis in the hepatopancreas was significantly increased in the cold stress group, indicating diminished function. Transcriptome sequencing identified 2615 differentially expressed genes (DEGs) following low temperature stress, of which 1147 and 1468 were up- and down-regulated, respectively. Functional analysis of DEGs indicated involvement in substance metabolism, antioxidant defences, signal transduction, and immune responses. Therefore, chronic cold stress can suppress metabolism and cause oxidative damage and immune deficiency in crayfish. The findings provide fundamental molecular information for further study of the regulatory mechanisms of cold tolerance in red claw crayfish.

8.
Water Sci Technol ; 79(11): 2156-2165, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31318353

RESUMO

The textile industry is developing rapidly in China. It generates large volumes of cotton dyeing pretreatment wastewater (CDPW). CDPW contains high concentrations of pollutants characterized by their strongly alkaline and recalcitrant nature for microbial degradation. This project aimed to evaluate the performance of a microbial electrolysis cell (MEC) coupled with anoxic/oxic (A/O) system (MEC-A/O) in treating CDPW, as well as analyze changes in microbial diversity. The results indicated that the effect of biological treatment in an electrolytic cell to treat CDPW was optimal at the voltage of 0.6V. The chemical oxygen demand (COD) removal efficiency under optimum conditions was 69.13%, higher than that of the A/O system alone (48.93%). Within a certain range, applied voltage was able to enhance microbial activity, increase the sludge concentration and enlarge the sludge particle size. At the same time, the applied voltage could effectively increase the abundance and the diversity of Bacteria and Archaea, as well as accelerate the degradation of pollutants.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Análise da Demanda Biológica de Oxigênio , China , Corantes , Eletrólise , Têxteis
9.
Waste Manag ; 91: 128-138, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203934

RESUMO

Gaseous emissions from municipal solid waste (MSW) disposal plants pose serious odor pollution and health risks. In this study, the emission of volatile organic compounds and carbon disulfide was compared in the main processing units of three disposal methods, i.e., landfilling, eco-mechanical biological treatment (EMBT) and anaerobic fermentation in a MSW disposal plant. Among the detected volatile compounds (VCs), the top ten odor compounds were methanethiol, dimethyl sulfide, dimethyl disulfide, carbon disulfide, styrene, m-xylene, 4-ethyltoluene, ethylbenzene, 2-hexyl ketone and n-hexane in the MSW disposal plant. Sulfur compounds were the main source of odor at the majority of sampling sites, and aromatic compounds were the dominant odor substrates at the tipping unit and sorting system of EMBT, while 2-hexanone was the major odor substrate at the tipping unit (AT) and sorting system (AS) of anaerobic fermentation and the landfill working surface. At AS and AT, the lifetime cancer risk values for 1,2-dichloroethane and trichloroethylene exceeded the carcinogenic risk value (>1.0E-04), and the hazard index values of naphthalene, trichloroethylene and acrolein all exceeded the acceptable level (>1). Therefore, special attention should be paid to VC emissions from MSW disposal facilities, and protection measures should be adopted for on-site workers to minimize health risks.


Assuntos
Poluentes Atmosféricos , Eliminação de Resíduos , Humanos , Odorantes , Resíduos Sólidos , Instalações de Eliminação de Resíduos
10.
Sci Total Environ ; 685: 836-846, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247433

RESUMO

The effects of microplastic exposure on the non-specific immune responses and intestinal microflora remain unclear. In this study, juveniles of the Chinese mitten crab (Eriocheir sinensis) were exposed to different concentrations of microplastics (0, 0.04, 0.4, 4, and 40 mg/L) for 7, 14, and 21 days to explore their effects. Under microplastic-induced stress, the contents or activities of most immune-related factors [haemocyanin (Hc), alkaline phosphatase (AKP), phenoloxidase (PO), lysozyme (LSZ), and acid phosphatase (ACP)] decreased after an initial increase in the low-dose or short exposure times in the haemolymph and hepatopancreas. The trends in Hc and LSZ gene expression were consistent with the corresponding changes in enzyme activities. Moreover, the haemocyte expression of caspase and MyD88 in the groups with microplastic-induced stress was higher than that in the control group, whereas the expression levels in the hepatopancreas were first increased and then decreased. Furthermore, the relative abundance of Firmicutes and Bacteroidetes decreased following exposure to 40 mg/L microplastics, whereas that of Fusobacteria and Proteobacteria increased. These results indicate that microplastics affect immune enzyme activity and immune-related gene expression and change the diversity and composition of the intestinal microflora in E. sinensis.


Assuntos
Braquiúros/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Plásticos/toxicidade , Poluentes da Água/toxicidade , Animais , Braquiúros/microbiologia
11.
Arch Oral Biol ; 102: 249-255, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31096116

RESUMO

OBJECTIVE: To determine whether occlusal alteration contributes to masticatory muscle damage by inducing oxidative stress. DESIGN: Thirty Sprague-Dawley rats were randomly divided into six groups, including occlusal interference groups (3 days, 7 days, 14 days, 21 days, and removal for 3 days) and a sham group. A rat experimental model of occlusal interference was generated by a 0.6-mm unilateral bite-raise. The rats were euthanised for evaluation of histologic changes in the masseter muscles using haematoxylin-eosin staining. To further investigate the role of oxidative stress and uncoupling protein (UCP3) in the development of occlusal dysfunction-induced masseter damage, levels of UCP3 protein were measured by western blot analysis. RESULTS: Compared with the sham group, the connective tissue of the masseter muscle was extended partially and inflammatory cells appeared following the induction of malocclusion. With respect to the oxidative stress markers, there were increases in malondialdehyde (MDA) content but decreases in superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities; furthermore, the expression of UCP3 was upregulated. After eliminating the occlusal interference for 3 days, the degree of inflammation was substantially alleviated, the MDA content decreased, and SOD and GPX activities increased. The expression of UCP3 decreased. CONCLUSIONS: Occlusal interference induces oxidative stress in the masseter muscle, regulated by UCP3. Overall, these findings have significant implications for the understanding of how occlusal dysfunction causes muscle fatigue and pain.


Assuntos
Oclusão Dentária , Músculo Masseter , Estresse Oxidativo , Animais , Músculos da Mastigação , Ratos , Ratos Sprague-Dawley
12.
Int J Biol Macromol ; 129: 809-817, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30784852

RESUMO

Na+/K+-ATPase (NKA) and carbonic anhydrase (CA) are ion transporters that play important roles in osmotic pressure balance in crustaceans. Oriental river prawn (Macrobrachium nipponense) is one of the most economically important shrimps in China. This species can live in freshwater and low-salt water, but the molecular mechanism of salinity regulation is unclear. In this study, full-length cDNAs of M. nipponense α-NKA and CA were obtained by rapid amplification of cDNA ends (RACE)-PCR (GenBank accession numbers MH378774 and MH827971, respectively), and characterised. Full-length cDNAs of Mnα-NKA (3778bp) and MnCA (1407bp) contain open reading frames of 3030bp and 930bp, respectively, encoding polypeptides of 1009 and 930 amino acids. Bioinformatic analysis showed that Mnα-NKA and MnCA harbour the representative features of NKAs and CAs, and share high homology with orthologs in other crustaceans. Quantitative real-time PCR revealed that Mnα-NKA and MnCA were expressed in various tissues, with highest expression in posterior gills and hepatopancreas. Both Mnα-NKA and MnCA were up-regulated in response to salinity acclimation, but expression patterns differed. Our results provide a theoretical basis for the mechanism regulating salinity acclimation in M. nipponense.


Assuntos
Anidrases Carbônicas/genética , Anidrases Carbônicas/metabolismo , /metabolismo , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Anidrases Carbônicas/química , Clonagem Molecular , Modelos Moleculares , Especificidade de Órgãos , Filogenia , Conformação Proteica , Análise de Sequência de DNA , ATPase Trocadora de Sódio-Potássio/química , Relação Estrutura-Atividade
13.
J Sex Med ; 16(1): 61-69, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30621927

RESUMO

INTRODUCTION: The relationship between periodontal disease (PD) and erectile dysfunction (ED) is still conflicting. AIM: To investigate whether a link between PD and ED exists, and if so, the degree to which it is significant. METHODS: The search strategy included using electronic databases and hand searching works published up to June 2018. MEDLINE via PubMed, EMBASE, Proceedings Web of Science, and Current Contents Connect were searched by 2 independent reviewers. Case-control, cohort, or cross-sectional studies including patients with measures of periodontitis and ED were included in the analysis. Quality assessments and sensitivity analysis of selected studies were performed. MAIN OUTCOME MEASURE: The strength of the association between PD and the prevalence of ED was evaluated. RESULTS: 5 case-control studies with 213,076 participants met the eligibility criteria and were included in the meta-analysis. Patients with PD were 2.85-fold more likely to be diagnosed with ED (OR = 2.85, 95% CI = [1.83, 4.46]). Asian men were reported to be 3.07 times more likely to be at greater risk for the prevalence of ED. Moreover, studies with high quality and case-control design showed 2 times higher risk for ED in PD (OR = 2.44, 95% CI = [1.44, 4.14]). However, the present evidence was not robust enough owing to the high heterogeneity and instability in sensitivity analysis. CLINICAL IMPLICATIONS: Patients with PD may have increased risk of ED, suggesting that dental hygiene should be of concern to clinicians when managing patients with ED. STRENGTH & LIMITATIONS: This article includes a large literature search to confirm the evidence that PD increases the occurrence of ED. However, there are several confounders, such as age and the type of ED, that failed to be adjusted and that generate bias and affect the correlation between the incidence of ED and PD. CONCLUSION: This system review and meta-analysis strengthens the evidence that PD might have important clinical implications for risk stratification of ED. Zhou X, Cao F, Lin Z. Updated evidence of association between periodontal disease and incident erectile dysfunction. J Sex Med 2019;16:61-69.

14.
Chemosphere ; 215: 74-81, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30312919

RESUMO

The widespread occurrence and accumulation of plastic waste have been globally recognized as a critical issue. However, there is limited information on the adverse effects of nanoplastics on freshwater invertebrates. In this study, the effects of a polystyrene nanoplastic on physiological changes (e.g., survival, growth, and reproduction) and expression levels of stress defense genes (oxidative stress-mediated and heat shock proteins) in the freshwater flea Daphnia pulex were measured. The results showed that the digestive organs of D. pulex were strongly fluorescent after exposure to the nanoplastic particles, and the 48-h median lethal concentration (LC 50) of the nanoplastic was determined to be 76.69 mg/L. In the 21-day chronic toxicity test, dose- and time-dependent relationships were observed for body length, and the time to first eggs was significantly prolonged in the 0.5 and 1 mg/L groups. The time to clutch was delayed, and total offspring per female and number of clutches were decreased in all the treatment groups. In addition, the offspring per clutch were significantly decreased in the 0.1 mg/L group. As the nanoplastic concentration increased, expression of stress defense genes (SOD, GST, GPx, and CAT) was first induced and then inhibited. The gene expressions of heat shock proteins (HSP70 and HSP90) were induced in all the treatment groups. Our results suggest that nanoplastics can be ingested by the freshwater cladoceran D. pulex and affect its growth and reproduction as well as induce stress defense.


Assuntos
Daphnia/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Plásticos/toxicidade , Poliestirenos/química , Estresse Fisiológico/efeitos dos fármacos , Animais , Daphnia/fisiologia , Feminino , Água Doce/química , Dose Letal Mediana , Reprodução/efeitos dos fármacos , Testes de Toxicidade Crônica
15.
Aquat Toxicol ; 204: 1-8, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30153596

RESUMO

The widespread occurrence and accumulation of micro- and nanoplastics in aquatic environments has become a growing global concern. Generally, natural aquatic populations are characterized by a variety of multi-structured age groups, for which physiological and biochemical responses typically differ. The freshwater cladoceran, Daphnia pulex, is a model species used extensively in environmental monitoring studies and ecotoxicology testing. Here, the effects of a polystyrene nanoplastic on the physiological changes (i.e., survival) and expression levels of stress defense genes (i.e., those encoding antioxidant-mediated and heat shock proteins) in this freshwater flea were measured. Results from acute bioassays were used to determine the respective nanoplastic LC50 values for five age groups (1-, 4-, 7-, 14- and 21-day-old individuals): the obtained values for the 1- and 21-day-old D. pulex groups were similar (i.e., not significantly different). The expression levels of genes encoding key stress defense enzymes and proteins-SOD, CAT, GST, GPx, HSP70, and HSP90-were influenced by the nanoplastic in all the age groups, but not in the same way for each. Significant differences were observed among all age groups in their expression of the gene encoding the energy-sensing enzyme AMPK (adenosine monophosphate-activated protein kinase) α, ß, and γ following exposure to the nanoplastic. Moreover, the expression of AMPK α was significantly increased in the 1-, 7-, and 21-day-old individuals exposed to nanoplastic relative to the control group. Together, these results indicate that age in D. pulex affects the sensitivity of its individuals to pollution from this nanoplastic, primarily via alterations to vital physiological and biochemical processes, such as cellular energy homeostasis and oxidation, which were demonstrated in vivo. We speculate that such age-related effects may extend to other nanoplastics and forms of pollution in D. pulex and perhaps similar marine organisms.


Assuntos
Adenilato Quinase/metabolismo , Envelhecimento/fisiologia , Daphnia/fisiologia , Exposição Ambiental/análise , Nanopartículas/toxicidade , Plásticos/toxicidade , Poliestirenos/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Adenilato Quinase/genética , Animais , Antioxidantes/metabolismo , Daphnia/efeitos dos fármacos , Ecotoxicologia , Água Doce/química , Regulação da Expressão Gênica/efeitos dos fármacos , Nanopartículas/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sobrevida , Fatores de Tempo , Poluentes Químicos da Água/toxicidade
16.
Artigo em Inglês | MEDLINE | ID: mdl-30030191

RESUMO

Desaturase enzymes play an important role in the synthesis of unsaturated fatty acids. In this study, a complete cDNA sequence of a Δ6 desaturase-like gene was cloned from the hepatopancreas of the red claw crayfish, Cherax quadricarinatus. The full-length 1885 bp sequence comprises a 5' UTR of 254 bp, 3' UTR of 234 bp, and an open reading frame (ORF) of 1377 bp encoding a 458 amino acid polypeptide (GenBank accession no. MF497442). Bioinformatics analysis revealed three conserved histidine-rich regions, a cytochrome b5 domain at the N-terminus, and a haem binding site (HPGG) in the cytochrome b5 domain, all of which are typical of Δ6 desaturases. Quantitative real-time PCR demonstrated significantly higher expression in the hepatopancreas than other tissues. After feeding crayfish four formulated diets in which fish oil was replaced by 0, 33, 67, or 100% highly unsaturated soybean oil for 8 weeks, Δ6 desaturase-like mRNA expression and enzyme activity were higher than in the fish oil only group. Additionally, a 4-week low temperature treatment at 25, 20, 15, or 9 °C increased Δ6 desaturase mRNA expression and enzyme activity with decreasing water temperature. These results may help us better understand the biosynthesis of unsaturated fatty acids in C. quadricarinatus.


Assuntos
Astacoidea/genética , Astacoidea/metabolismo , Regulação da Expressão Gênica , Linoleoil-CoA Desaturase/genética , Linoleoil-CoA Desaturase/metabolismo , Temperatura Ambiente , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Ácidos Graxos Insaturados/biossíntese , Linoleoil-CoA Desaturase/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência
17.
Arch Oral Biol ; 93: 3-11, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29800802

RESUMO

OBJECTIVE: To assess the association between interleukin gene polymorphism and recurrent aphthous stomatitis (RAS). DESIGNS: Two electronic databases, PubMed and Embase, were utilized to assemble potentially relevant studies meeting the inclusion criteria. A meta-analysis was conducted using Revman 5.3 software (London, UK), and the pooled odds ratio (OR) and 95% confidence interval (CI) were then used to evaluate the strength of the relationship between the gene polymorphisms of IL-1beta(-511C/T), IL-1beta(+3954C/T), IL-6(-174G/C) and IL-10(-1082G/A) and the risk of RAS. RESULTS: Ten studies were included in the final meta-analysis, with 884 cases and 1104 controls participating. The results demonstrated that the polymorphism of IL-1beta(-511C/T) significantly increased the probability of the development of RAS in Europeans. (T vs. C: OR = 1.35, 95%CI = 1.09-1.67; CC vs. CT + TT: OR = 1.77, 95%CI = 1.24-2.53; CC vs. TT: OR = 1.86, 95%CI = 1.18-2.95). Furthermore, the C allele in IL-1beta(+3954C/T) was determined to be related to the risk of RAS in Americans (C vs. T: OR = 1.52, 95%CI = 1.07-2.17) and the presence of the C gene was considered a risk variant (CC + CT vs. TT: OR = 1.46, 95%CI = 1.01-2.11), but no relationship was found between the polymorphism of IL-10(-1082G/A) and the risk of RAS. CONCLUSIONS: The meta-analysis suggested that the mutation of IL-1beta(-511C/T) in Europe and IL-1beta(+3954C/T) in America tend to increase the risk of RAS, but the polymorphism of IL-10(-1082G/A) appears to have no association with RAS risk in America. Further study is required to confirm the above conclusions.


Assuntos
Predisposição Genética para Doença , Interleucina-1beta/genética , Polimorfismo de Nucleotídeo Único , Estomatite Aftosa/genética , Humanos , Interleucina-10/genética , Interleucina-6/genética , Mutação/genética , Recidiva
18.
Aquat Toxicol ; 200: 28-36, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29709883

RESUMO

As a widespread and ubiquitous pollutant of marine ecosystems, microplastic has the potential to become an emerging global threat for aquatic organisms. The present study aims to elucidate the effects of microplastics on the growth, accumulation and oxidative stress response in the liver of Eriocheir sinensis. Fluorescent microplastic particles (diameter = 0.5 µm) accumulated in the gill, liver and gut tissues of E. sinensis were investigated when crabs were exposed to a concentration of 40000 µg/L for 7 days. A 21 day toxicity test suggested that the rate of weight gain, specific growth rate, and hepatosomatic index of E. sinensis decreased with increasing microplastic concentration (0 µg/L, 40 µg/L, 400 µg/L, 4000 µg/L and 40000 µg/L). The activities of AChE and GPT in crabs exposed to microplastics were lower than those in control group. GOT activity increased significantly after exposure to a low concentration of microplastics and then decreased continuously with increasing microplastic concentrations. The activities of superoxide dismutase (SOD), aspartate transaminase (GOT), glutathione (GSH), and glutathione peroxidase (GPx) increased in specimens exposed to low concentrations of microplastics (40 and 400 µg/L) compared to the control and decreased in organisms exposed to high concentrations (4000 and 40000 µg/L). In contrast, the activities of acetylcholinesterase, catalase (CAT), and alanine aminotransferase were significantly lower in the organisms exposed to microplastics compared to control animals. Upon exposure to increasing microplastic concentrations, the expression of genes encoding the antioxidants SOD, CAT, GPx and glutathione S-transferase in the liver decreased after first increasing. Exposure to microplastics increased the expression of the gene encoding p38 in the MAPK signaling pathway and significantly decreased the expressions of genes encoding ERK, AKT, and MEK. The results of this study demonstrate that microplastics can accumulate in the tissues of E. sinensis and negatively affect growth. In addition, exposure to microplastics causes damage and induces oxidative stress in the hepatopancreas of E. sinensis. The findings provide basic biological data for environmental and human risk assessments of microplastics of high concern.


Assuntos
Braquiúros/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Plásticos/toxicidade , Poliestirenos/química , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Braquiúros/efeitos dos fármacos , Braquiúros/crescimento & desenvolvimento , Catalase/genética , Catalase/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Plásticos/química , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Testes de Toxicidade , Poluentes Químicos da Água/química
19.
Mar Pollut Bull ; 127: 429-436, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29475681

RESUMO

The effects of enclosed, semi-closed, and opened reclamation methods on the macrobenthos community structure were investigated. Compared with their paired controls, water salinity decreased sharply in the enclosed reclamation region with no apparent change in the opened reclamation region. Declining species and biodiversity was observed in the reclamation regions, but the extent of this declining trend was weaker in the semi-closed and opened reclamations than in the enclosed reclamation region. The ABC curve indicated that the enclosed reclamation was disturbed, whereas the semi-closed and opened reclamations were undisturbed. Taken together, these results suggest that reclamation may have a negative effect on the community and health status of macrobenthos in the intertidal wetlands of the Yangtze Estuary. Semi-closed and opened reclamation methods may mitigate the problem of a salinity decrease caused by enclosed reclamation, while also having a relatively weaker negative effect on community structure and wetland habitat.


Assuntos
Ecossistema , Estuários , Biodiversidade , China , Ecologia , Salinidade , Áreas Alagadas
20.
Gene ; 582(1): 59-68, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-26828612

RESUMO

Daphnia carinata are unique freshwater crustaceans that undergo both sexual and asexual reproduction, depending on environmental factors. While the molecular mechanism behind the reproductive transformation has been unknown, chemosensory proteins (CSPs) may be involved. We have cloned the cDNA sequences of two CSP genes from D. carinata using primers based on homologous sequences and rapid amplification of cDNA ends (RACE). The full-length cDNA of DacaCSP2 (GenBank accession no: KM624608) was 632 bp, with an ORF (open reading frame) of 330 bp encoding a 12.02 kDa protein; and the full-length cDNA of DacaCSP3 (GenBank accession no: KM624609) was 935 bp, with an ORF of 342 bp encoding a 12.78kDa protein. Both CSPs encoded an N-terminal signal peptide, four conserved cysteines, an OS-D superfamily domain, a 2Fe-2S ferredoxin domain, an anaphylatoxin domain and an EGF-like domain. DaCaCSP2 and DaCaCSP3 proteins were most closely related to CSPs from Daphnia pulex and were more distantly related to CSPs from other insects. Using quantitative PCR, we found expression levels of DaCaCSP2 and DaCaCSP3 mRNA were highest in sexual females, followed by parthenogenetic females, and lowest in males. The expression levels of DaCaCSP2 and DaCaCSP3 mRNA also increased at lower temperatures, which suggested they could respond to environmental cues. Whole mount in situ hybridization (ISH) showed that DaCaCSP2 and DaCaCSP3 were expressed mainly in the ovaries, summer eggs, thoracic limbs, rectum and second antennae in sexual females; while they were expressed mainly in the ovaries, thoracic limbs, rectum and second antennae in parthenogenetic females. Together, these results suggest that DacaCSP2 and DacaCSP3 may respond to environmental cues and control the reproductive switch from sexual to asexual reproduction in D. carinata.


Assuntos
Proteínas de Artrópodes/genética , Proteínas de Ligação a DNA/genética , Chaperonas Moleculares/genética , Filogenia , Reprodução/genética , Sequência de Aminoácidos/genética , Animais , Clonagem Molecular , Proteínas de Ligação a DNA/biossíntese , Daphnia/genética , Daphnia/crescimento & desenvolvimento , Feminino , Água Doce , Hibridização In Situ , Masculino , Chaperonas Moleculares/isolamento & purificação , Partenogênese/genética , Homologia de Sequência
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