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1.
Arch Microbiol ; 206(4): 140, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441642

RESUMO

Limosilactobacillus reuteri is an indigenous inhabitant of the animal gut known for its probiotic effects on the host. In our previous study, a large number of L. reuteri strains were isolated from the gastrointestinal tract of mice recovering from ulcerative colitis, from which we randomly selected L. reuteri RE225 for whole genome sequencing to explore its probiotic properties. The results of next-generation sequencing and third-generation single molecule sequencing showed that L. reuteri RE225 contained many genes encoding functional proteins associated with adhesion, anti-inflammatory and pathogen inhibition. And compared to other L. reuteri strains in NCBI, L. reuteri RE225 has unique gene families with probiotic functions. In order to further explore the probiotic effect of the L. reuteri RE225, the derived peptides were identified by LC-MS/MS, and the peptides with tumor necrosis factor-α binding ability were screened by reverse molecular docking and microscale thermophoresis. Finally, cell experiments demonstrated the anti-inflammatory ability of the peptides. Western blotting and qPCR analyses confirmed that the selected peptides might alleviate LPS-induced inflammation in NCM460 cells by inhibiting JAK2/STAT3 pathway activation.


Assuntos
Colite Ulcerativa , Limosilactobacillus reuteri , Animais , Camundongos , Limosilactobacillus reuteri/genética , Colite Ulcerativa/tratamento farmacológico , Cromatografia Líquida , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem , Peptídeos/genética , Peptídeos/farmacologia , Sequenciamento Completo do Genoma
2.
Anal Bioanal Chem ; 416(10): 2493-2501, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451276

RESUMO

Exposure to poly- and perfluoroalkyl substances (PFASs) can result in bioaccumulation. Initial findings suggested that PFASs could accumulate in tissues rich in both phospholipids and proteins. However, our current understanding is limited to the average concentration of PFASs or phospholipid content across entire tissue matrices, leaving unresolved the spatial variations of lipid metabolism associated with PFOA in zebrafish tissue. To address gap, we developed a novel methodology for concurrent spatial profiling of perfluorooctanoic acid (PFOA) and individual phospholipids within zebrafish hepatic tissue sections, utilizing matrix-assisted laser desorption/ionization time of flight imaging mass spectrometry (MALDI-TOF-MSI). 5-diaminonapthalene (DAN) matrix and laser sensitivity of 50.0 were optimized for PFOA detection in MALDI-TOF-MSI analysis with high spatial resolution (25 µm). PFOA was observed to accumulate within zebrafish liver tissue. H&E staining results corroborating the damage inflicted by PFOA accumulation, consistent with MALDI MSI results. Significant up-regulation of 15 phospholipid species was observed in zebrafish groups exposed to PFOA, with these phospholipid demonstrating varied spatial distribution within the same tissue. Furthermore, co-localized imaging of distinct phospholipids and PFOA within identical tissue sections suggested there could be two distinct potential interactions between PFOA and phospholipids, which required further investigation. The MALDI-TOF-IMS provides a new tool to explore in situ spatial distributions and variations of the endogenous metabolites for the health risk assessment and ecotoxicology of emerging environmental pollutants.


Assuntos
Caprilatos , Fluorocarbonos , Perciformes , Animais , Fosfolipídeos/análise , Peixe-Zebra , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Fígado/química , Fluorocarbonos/toxicidade , Fluorocarbonos/metabolismo
3.
Environ Sci Process Impacts ; 26(4): 700-709, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38376352

RESUMO

Perfluorooctanoic acid (PFOA) is an emerging persistent organic pollutant. Exposure to PFOA was observed to have a correlation with the expression levels of phospholipids. However, there are currently no studies that directly visualize the effects of PFOA on phospholipids. To this end, matrix-assisted laser desorption/ionization time of flight imaging mass spectrometry (MALDI-TOF-IMS) was used to visualize changes in phospholipids in the different tissues of zebrafish following exposure to PFOA. This study found that the major perturbed phospholipids were phosphatidylcholine (PC), diacylglycerol (DG), phosphatidic acid (PA), phosphatidylglycerol (PG), sphingomyelin (SM), and triacylglycerol (TG). These perturbed phospholipids caused by PFOA were reversible in some tissues (liver, gill, and brain) and irreversible in others (such as the highly exposed intestine). Moreover, the spatial distribution of perturbed phospholipids was mainly located around the edge or center of the tissues, implying that these tissue regions need special attention. This study provides novel insight into the biological toxicity and toxicity mechanisms induced by emerging environmental pollutants.


Assuntos
Caprilatos , Fluorocarbonos , Fosfolipídeos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Fluorocarbonos/metabolismo , Fosfolipídeos/metabolismo , Caprilatos/metabolismo , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
4.
Front Microbiol ; 14: 1295058, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033563

RESUMO

Many studies have focused on the influence of dietary supplements on gut microbiota composition, but limited research have reported their effects on specific bacterial species in the gut. Lactiplantibacillus plantarum is one of the most widely studied probiotics, with a wide range of sources and good environmental adaptability. In this study, in order to elucidate the adaptation strategies of L. plantarum to the gut of mice supplemented with carbohydrates, peptides and minerals, whole genome resequencing and intracellular metabolites detection were performed, and high-frequency mutant genes and differential metabolites were screened. The results suggested different types of dietary supplements do have different effects on L. plantarum from the gut of mice. Additionally, KEGG annotation unveiled that the effects of these dietary supplements on the gene level of L. plantarum primarily pertained to environmental information processing, while the differential metabolites were predominantly associated with metabolism. This study provided new perspectives on the adaptive mechanism of L. plantarum in response to the host's gut environment, suggesting that the diversity of the genome and metabolome of L. plantarum was correlated with dietary supplements. Furthermore, this study offered useful guidance in the effective utilization of dietary supplements.

5.
BMC Cardiovasc Disord ; 23(1): 495, 2023 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805494

RESUMO

BACKGROUND: Acute coronary syndrome (ACS) remains the leading cause of death and disability worldwide, especially when combined with type 2 diabetes mellitus (T2DM). Many multicenter randomized controlled trials have established the cardiovascular benefits of Sodium-Glucose cotransporter 2 inhibitors (SGLT-2i) in patients with T2DM at high cardiovascular risk. However, these studies did not include patients in the early stages of acute coronary events. This study investigated the cardiovascular protective effects of SGLT-2i in patients with ACS and T2DM. METHODS: A total of 232 hospitalized patients with ACS and T2DM were enrolled and divided into two groups based on their hypoglycemic drug treatment: the SGLT-2i and the non-SGLT-2i groups. Kaplan-Meier analysis and Cox regression were used to compare adverse cardiovascular outcomes in both groups. RESULTS: There were no significant differences in the hospital clinical outcomes between the SGLT-2i and non-SGLT-2i groups. The adverse cardiovascular outcomes did not significantly differ between both groups (hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.35-1.25, P = 0.195). Moreover, the rehospitalization rates for ACS or heart failure (HF) were not significantly different between both groups (adjusted HR 0.56, 95%CI 0.28-1.10, P = 0.093). When analyzed separately, there was no significant difference in rehospitalizations for ACS (HR 0.87, 95% CI 0.40-1.87, P = 0.713). However, the SGLT-2i group showed lower rates of rehospitalizations for HF (adjusted HR 0.20, 95% CI 0.04-0.96, P = 0.045). Additionally, there was no significant difference in cardiovascular mortality between both groups (HR 1.75, 95% CI 0.28-10.97, P = 0.543). Notably, the SGLT-2i group exhibited a higher angina symptom control rate than the non-SGLT-2i group (adjusted odd ration (OR) 0.45, 95%CI 0.21-0.93, P = 0.031). CONCLUSION: In recently diagnosed patients with ACS, who have T2DM, early initiation of SGLT-2i was associated with a lower risk of rehospitalization for HF and a higher rate of angina symptom control.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Estudos Retrospectivos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/prevenção & controle , Glucose , Sódio
6.
Chemosphere ; 313: 137364, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427582

RESUMO

Due to dissolved oxygen (DO) limited nitrogen removal efficiency in constructed wetlands (CWs), two representative oxygen-suppling CWs, i.e., tidal flow constructed wetlands (TFCWs) and intermittently aerated constructed wetlands (IACWs) were proposed to compare the effect of oxygen supply strategies on the nitrogen removal performance and mechanism. Results showed that the removal efficiencies of NH4+-N and COD in IACWs were as high as 90.35-97.14% and 91.14-92.44%, respectively. In terms of TN, TFCWs (83.82%) showed a significantly higher removal efficiency than IACWs, and this result was derived with the flooded/drained phase (FP/DP) ratio of 21 h:3 h in TFCWs, because rhythmic FP and DP formed a high oxygen gradient at different depths of the system, which intensified the nitrification and denitrification simultaneously. The potential nitrifying and denitrifying bacteria (e.g., Nitrospira, Azospira, Haliangium, Bradyrhizobium and Arenimonas) were enriched more significantly in TFCWs compared with IACWs, as well as Bacillus for simultaneous nitrification and denitrification, which promoted nitrogen transformation together. Also, the results of molecular ecological network analysis showed that bacterial community structure in IACWs was more complex and robust than in TFCWs, because there were obviously more nodes and links as well as a higher proportion of negative interference. However, the relationship between genera in TFCWs was closer depending on shorter path distances, and the keystone genus (Nitrosomonas) in related to nitrification was considered to play an important role in nitrogen transformation performance.


Assuntos
Desnitrificação , Águas Residuárias , Áreas Alagadas , Nitrogênio/análise , Nitrificação , Bactérias , Oxigênio , Eliminação de Resíduos Líquidos
7.
Mol Cancer Res ; 20(11): 1636-1645, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-35920801

RESUMO

Ferroptosis is a newly-discovered cell death mechanism involved in the progression of various tumors, the role of noncoding RNAs (ncRNAs) in it was relatively less explored. This study identified the low levels of a recently studied long noncoding RNA (lncRNA), A2M-AS1, in pancreatic cancer and suggested its positive correlation with the overall survival time of patients with pancreatic cancer. A2M-AS1 was mainly localized in the cytoplasm, inhibiting the cellular proliferation, migration, and invasion as well as the tumor growth of the pancreatic cancer cells. Moreover, the Erastin-induced ferroptosis increased the expression levels of A2M-AS1. The overexpression of A2M-AS1 promoted ferroptosis in the pancreatic cancer, which was inhibited by the silencing of A2M-AS1. Mechanically, A2M-AS1 could directly interact with the poly (rC) binding protein 3 (PCBP3), which plays an important role in the process of iron metabolism, thereby promoting the ferroptosis in pancreatic cancer. In addition, the A2M-AS1/PCBP3 axis could facilitate the p38 activation and inhibit the phosphorylation of the AKT-mTOR signaling pathway; all these participate in regulating ferroptosis. In conclusion, the regulation of ferroptosis by targeting the A2M-AS1/PCBP3 axis might provide a novel target for the treatment of pancreatic cancer in the future. IMPLICATIONS: A2M-AS1 might be a potential novel therapeutic target for patients with pancreatic cancer in the future.


Assuntos
Ferroptose , Neoplasias Pancreáticas , RNA Longo não Codificante , Humanos , alfa-Macroglobulinas/genética , alfa-Macroglobulinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Pancreáticas
8.
Ecotoxicol Environ Saf ; 232: 113226, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35093811

RESUMO

Laser ablation-isotope ratio mass spectrometry (LA-IRMS) allows the mapping analysis of carbon isotope (δ13C) signature in organism samples.Matrix assisted laser desorption ionization time-of-flightimaging mass spectrometry (MALDI-TOF-IMS) enables image of target directly. In this study, the distribution of δ13C and fullerenol nanoparticles in Daphnia magna (D. magna) exposed to different fullerenol solution are mapped using the LA-IRSM and MALDI-TOF-IMS for comparison. We visualize thedistribution of fullerenol nanoparticles mainly in the intestine, also in other parts of the body as well. This is the first time that fullerenol nanoparticles was found outside the intestine of D. magna, which has been confirmed by the two imaging methods individually. Although the both imaging methods are applicable to in-situ visualize the localization and spatial distribution of fullerenol nanoparticles in organisms, MALDI-TOF-IMS is more suitable, in terms of sample preparation and image resolution. The results of our study will also provide a new idea and method for the research of environmental toxicology.


Assuntos
Terapia a Laser , Nanopartículas , Animais , Daphnia , Fulerenos , Isótopos , Lasers , Nanopartículas/química , Nanopartículas/toxicidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
9.
Insects ; 12(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34357265

RESUMO

Mitogenomes have been widely used for exploring phylogenetic analysis and taxonomic diagnosis. In this study, the complete mitogenomes of five species of Filchnerella were sequenced, annotated and analyzed. Then, combined with other seven mitogenomes of Filchnerella and four of Pamphagidae, the phylogenetic relationships were reconstructed by maximum likelihood (ML) and Bayesian (BI) methods based on PCGs+rRNAs. The sizes of the five complete mitogenomes are Filchnerella sunanensis 15,656 bp, Filchnerella amplivertica 15,657 bp, Filchnerella nigritibia 15,661 bp, Filchnerella pamphagoides 15,661 bp and Filchnerella dingxiensis 15,666 bp. The nucleotide composition of mitogenomes is biased toward A+T. All tRNAs could be folded into the typical clover-leaf structure, except that tRNA Ser (AGN) lacked a dihydrouridine (DHU) arm. The phylogenetic relationships of Filchnerella species based on mitogenome data revealed a general pattern of wing evolution from long wing to increasingly shortened wing.

10.
Food Funct ; 12(12): 5387-5398, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33983361

RESUMO

Rheumatoid arthritis is emerging as a chronic autoimmune disease worldwide. In this study, the beneficial effects of tuna oil (TO) on collagen-induced arthritis (CIA) mice were investigated. Dietary administration of TO relieved arthritis severity and joint bone erosion, and ameliorated systemic inflammation. Furthermore, TO treatments regulated the phosphorylation of nuclear factor-kappa B (NF-κB) and Wnt1/ß-catenin signaling pathways in the joint, enhanced osteoblastogenesis biomarkers and suppressed osteoclastogenesis biomarkers, and subsequently re-balanced bone remodeling. Moreover, the impaired intestinal epithelial barrier was repaired after TO treatments, along with gut microbiota modulation. By employing fecal microbiota transplantation, we clarified that the beneficial effects of TO in CIA alleviation were mediated by the modulated gut microbiota. These results indicated that gut microbiota mediated the protective effects of tuna oil on collagen-induced arthritis in mice.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/terapia , Colágeno/efeitos adversos , Óleos de Peixe/farmacologia , Microbioma Gastrointestinal/fisiologia , Atum/metabolismo , Animais , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/patologia , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/patologia , Biomarcadores , Citocinas/análise , Transplante de Microbiota Fecal , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Proteína Wnt1 , beta Catenina
11.
Mol Immunol ; 132: 184-191, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33446394

RESUMO

Th9 cells are a defined CD4+ helper T cell subgroup found to promote or suppress oncogenesis in a context-dependent manner. How microRNAs (miRNAs) shape Th9 cell functionality, however, remains to be studied. Herein, we determined that miR-143/145 is downregulated during Th9 differentiation. When these miRNAs were upregulated, this inhibited Th9 differentiation, proliferation, and IL-9 production. Overexpressing miR-143/145 in Th9 cells further suppressed NFATc1 expression at the protein and mRNA level, whereas the opposite phenotype was observed when miR-143/145 was downregulated in these cells. NFATc1 silencing markedly inhibited Th9 cell differentiation, whereas overexpressing this transcription factor was sufficient to reverse miR-143/145-associated phenotypes in these cells. These findings thus indicate that the ability of miR-143/145 to inhibit Th9 cell differentiation is attributable to their ability to target and suppress NFATc1 expression. Overall, our results highlight a novel mode of action whereby miR-143/145 controls Th9 differentiation, suggesting that this pathway may be amenable to therapeutic targeting in the context of anti-cancer treatment in the future.


Assuntos
Diferenciação Celular/genética , MicroRNAs/imunologia , Fatores de Transcrição NFATC/genética , Animais , Linfócitos T CD4-Positivos/fisiologia , Células Cultivadas , Regulação para Baixo/genética , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/genética , Linfócitos T Auxiliares-Indutores/fisiologia , Regulação para Cima/genética
12.
Front Genet ; 11: 595361, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363572

RESUMO

BACKGROUND: Intratumoral oxidative stress (OS) has been associated with the progression of various tumors. However, OS has not been considered a candidate therapeutic target for pancreatic cancer (PC) owing to the lack of validated biomarkers. METHODS: We compared gene expression profiles of PC samples and the transcriptome data of normal pancreas tissues from The Cancer Genome Atlas (TCGA) and Genome Tissue Expression (GTEx) databases to identify differentially expressed OS genes in PC. PC patients' gene profile from the Gene Expression Omnibus (GEO) database was used as a validation cohort. RESULTS: A total of 148 differentially expressed OS-related genes in PC were used to construct a protein-protein interaction network. Univariate Cox regression analysis, least absolute shrinkage, selection operator analysis revealed seven hub prognosis-associated OS genes that served to construct a prognostic risk model. Based on integrated bioinformatics analyses, our prognostic model, whose diagnostic accuracy was validated in both cohorts, reliably predicted the overall survival of patients with PC and cancer progression. Further analysis revealed significant associations between seven hub gene expression levels and patient outcomes, which were validated at the protein level using the Human Protein Atlas database. A nomogram based on the expression of these seven hub genes exhibited prognostic value in PC. CONCLUSION: Our study provides novel insights into PC pathogenesis and provides new genetic markers for prognosis prediction and clinical treatment personalization for PC patients.

13.
Anal Bioanal Chem ; 412(27): 7649-7658, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32876724

RESUMO

With the wide application of fullerenols in biomedicine, their environmental exposure risks and toxicity to organisms have been extensively studied. However, there is still a lack of knowledge about the distribution of fullerenols in organisms as an important aspect of their mechanism of toxicity. High-resolution matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an emerging technology for researching the distribution of molecules in biological tissue samples. Using this high-resolution technique, we map the distribution of fullerenols in zebrafish tissues, and the results suggest that fullerenols enter the gill, intestine, and muscle tissues and even permeate the blood-brain barrier, reaching the brain of zebrafish after aquatic exposure. Moreover, from the MS images of fullerenols, the distribution amount of fullerenols is highest in the gill, followed by that in the intestine and the small amount in muscle and brain tissues. As an emerging environmental pollutant, the establishment of this research method will provide a new method for the study of the environmental toxicity of carbon nanomaterials. Our results also indicated that this high-resolution imaging method could be applied to explore the mechanism of interaction between carbon nanomaterials and biological systems at the cellular level in the future.


Assuntos
Fulerenos/análise , Poluentes Químicos da Água/análise , Peixe-Zebra , Animais , Brânquias/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Distribuição Tecidual , Peixe-Zebra/metabolismo
14.
Onco Targets Ther ; 13: 3789-3800, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440147

RESUMO

PURPOSE: Our previous experiments confirmed that T helper type 9 (Th9) cells were involved in the occurrence and development of malignant ascites caused by liver cancer. The current study investigated the mechanism underlying microRNA (miR-145)-mediated inhibition of Th9 cells in an malignant ascites model with liver cancer. MATERIALS AND METHODS: CD4+ T cells were induced to differentiate Th9 cells after transfection with miR-145 mimics or negative control. A malignant ascites mouse model was transfected with miR-145agomir or negative control. Th9 cells were detected by flow cytometry. Enzyme-linked immunosorbent assay was applied to detect the interleukin 9 (IL-9) cytokine and hypoxia-inducible factor 1 alpha (HIF-1α). RT-PCR was used to detect the expression of miR-145 and phosphatidylinositol-3-kinase/Akt/mammalian target of rapamycin/p70 ribosomal protein S6 kinase/HIF-1α (PI3K/Akt/mTOR/p70S6K/HIF-1α) mRNA. Western blotting and immunofluorescence were performed to detect the expression of PI3K/Akt/mTOR/p70S6K/HIF-1α-related proteins. RESULTS: In vitro experiments showed that miR-145 inhibited Th9 cell polarization, HIF-1α expression, and PI3K/Akt/mTOR/p70S6K pathway activation. In the malignant ascites mouse model, miR-145 also demonstrated inhibitory effects on Th9 cell differentiation through the PI3K/Akt/mTOR/p70S6K/HIF-1α pathway. CONCLUSION: miR-145 may inhibit Th9 cell differentiation through the PI3K/Akt/mTOR/p70S6K/HIF-1α pathway. These findings suggest a novel therapeutic target for malignant ascites from liver cancer.

15.
Ecotoxicol Environ Saf ; 191: 110173, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31935558

RESUMO

In aquatic organisms, dietary exposure to nanomaterials is not only one of the important uptake pathways, but it is also one method to assess the transmission risk of the food chain. To address this concern, we quantitatively investigated the accumulation and depuration of fullerenols in the tissues of zebrafish after exposure to fullerenols-contaminated Daphnia magna. After exposure to 13C-labelled fullerenol solution at a concentration of 2.5 mg/L for 72 h, the steady state concentration of fullerenols in D. magna was 31.20 ± 1.59 mg/g dry weight. During the 28 d uptake period for zebrafish, fullerenols in the tissues increased in a tissue- and day-dependent manner, and the major target tissues of fullerenols were the intestines and liver, followed by the gill, muscle, and brain. The kinetic parameters of uptake and depuration were also quantitatively analyzed. After depuration for 15 d, a certain amount of residual fullerenols remained in the tissues, especially the brain, where approximately 64 d may be needed to achieve 90% of the cumulative concentration depuration. The calculated distribution-based trophic transfer factors (TTFd values) (from 0.26 to 0.49) indicated that the tissue biomagnification of fullerenols by zebrafish through dietary exposure may not occur. Transmission electron microscopy (TEM) confirmed the presence of fullerenols in D. magna and the tissues of zebrafish. Our research data are essential for thoroughly understanding of the fate of nanoparticles through the dietary exposure pathway and directing future tissue bioeffect studies regarding target tissues for further research.


Assuntos
Exposição Dietética/análise , Fulerenos/farmacocinética , Nanopartículas/metabolismo , Poluentes Químicos da Água/farmacocinética , Peixe-Zebra/metabolismo , Animais , Bioacumulação , Daphnia/metabolismo , Cadeia Alimentar , Distribuição Tecidual
16.
Environ Sci Technol ; 52(21): 12133-12141, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30335979

RESUMO

Fullerenol, a water-soluble polyhydroxylated fullerene nanomaterial, enters aquatic organisms and ecosystems through different ingestion exposures and may pose environmental risks. The study of their uptake routes and transfer in aquatic systems is scarce. Herein, we quantitatively investigated the aquatic uptake and transfer of 13C-fullerenols from Scenedesmus obliquus to Daphnia magna using 13C-skeleton-labeling techniques. The bioaccumulation and depuration of fullerenol in Daphnia magna increased with exposure doses and time, reaching steady state within 16 h in aqueous and feeding-affected aqueous routes. The capacity of Daphnia magna to ingest fullerenol via the aqueous route was much higher than that via the dietary route. From the aqueous to feeding-affected aqueous, the kinetic analysis demonstrated the bioaccumulation factors decreases, which revealed that algae suppressed Daphnia magna uptake of fullerenols. The aqueous route was the primary fullerenols ingestion pathway for Daphnia magna. Kinetic analysis of the accumulation and transfer in Daphnia magna via the dietary route indicated low transfer efficiency of fullerenol along the Scenedesmus obliquus-Daphnia magna food chain. Using stable isotope labeling techniques, these quantitative data revealed that carbon nanomaterials underwent complex aquatic accumulation and transfer from primary producers to secondary consumers and algae inhibited their transfer in food chains.


Assuntos
Fulerenos , Scenedesmus , Poluentes Químicos da Água , Animais , Daphnia , Ecossistema , Cinética
17.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4063-4064, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25629495

RESUMO

The complete mitochondrial genome of Sinotmethis brachypterus Zheng & Xi, 1985, which was collected from the Gansu Province of China, is reported here. It is 15,662 bp in length and contains 72.6% AT. All Sinotmethis brachypterus protein-coding sequences start with a typical ATN codon, excluding cox1 and nad6. The usual termination codon (TAN) and incomplete stop codons (T, TA) were found from 13 protein-coding genes. All tRNA genes could be folded into the typical cloverleaf secondary structure, excluding trnS(AGN) which forms another structure. The sizes of the large and small ribosomal RNA genes are 1320 and 852 bp, respectively. The AT content of the A + T-rich region is 84.2%.


Assuntos
Genoma de Inseto/genética , Genoma Mitocondrial/genética , Gafanhotos/genética , Ortópteros/genética , Animais , Composição de Bases/genética , China , Códon de Terminação/genética , DNA Mitocondrial/genética , Fases de Leitura Aberta/genética , RNA Ribossômico/genética , RNA de Transferência/genética , Análise de Sequência de DNA/métodos
18.
Int J Mol Sci ; 15(8): 13406-23, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25089875

RESUMO

To study the toxic mechanisms of lead (Pb) in plants, the effects of Pb on the morphology and structure of the nucleolus in root tip meristematic cells of Allium cepa var. agrogarum L. were investigated. Fluorescence labeling, silver-stained indirect immunofluorescent microscopy and western blotting were used. Fluorescence labeling showed that Pb ions were localized in the meristematic cells and the uptake and accumulation of Pb increased with treatment time. At low concentrations of Pb (1-10 µM) there were persistent nucleoli in some cells during mitosis, and at high concentration (100 µM) many of the nucleolar organizing regions were localized on sticky chromosomes in metaphase and anaphase cells. Pb induced the release of particles containing argyrophilic proteins to be released from the nucleus into the cytoplasm. These proteins contained nucleophosmin and nucleolin. Pb also caused the extrusion of fibrillarin from the nucleus into the cytoplasm. Western blotting demonstrated the increased expression of these three major nucleolar proteins under Pb stress.


Assuntos
Nucléolo Celular/efeitos dos fármacos , Chumbo/toxicidade , Cebolas/crescimento & desenvolvimento , Nucléolo Celular/química , Meristema/química , Meristema/citologia , Meristema/efeitos dos fármacos , Microscopia Confocal , Mitose/efeitos dos fármacos , Nucleoproteínas/química , Nucleoproteínas/metabolismo , Cebolas/efeitos dos fármacos , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raízes de Plantas/citologia , Fatores de Tempo
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