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1.
Environ Pollut ; 351: 124084, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38697245

RESUMEN

Due to the potential impacts of microplastics (MPs) and nanoplastics (NPs) on algal growth and thereby affect the climate-relevant substances, dimethylsulfoniopropionate (DMSP) and dimethyl sulfide (DMS), we studied the polystyrene (PS) MPs and NPs of 1 µm and 80 nm impacts on the growth, chlorophyll content, reactive oxygen species (ROS), antioxidant enzyme activity, and DMS/DMSP production in Emiliania huxleyi. E. huxleyi is a prominent oceanic alga that plays a key role in DMS and DMSP production. The results revealed that high concentrations of MPs and NPs inhibited the growth, carotenoid (Car), and Chl a concentrations of E. huxleyi. However, short-time exposure to low concentrations of PS MPs and NPs stimulated the growth of E. huxleyi. Furthermore, high concentrations of MPs and NPs resulted in an increase in the superoxide anion radical (O2.-) production rate and a decrease in the malondialdehyde (MDA) content compared with the low concentrations. Exposure to MPs and NPs at 5 mg L-1 induced superoxide dismutase (SOD) activity as a response to scavenging ROS. High concentrations of MPs and NPs significantly inhibited the production of DMSP and DMS. The findings of this study support the potential ecotoxicological impacts of MPs and NPs on algal growth, antioxidant system, and dimethylated sulfur compounds production, which maybe potentially impact the global climate.


Asunto(s)
Antioxidantes , Haptophyta , Especies Reactivas de Oxígeno , Sulfuros , Compuestos de Sulfonio , Contaminantes Químicos del Agua , Antioxidantes/metabolismo , Compuestos de Sulfonio/metabolismo , Haptophyta/crecimiento & desarrollo , Haptophyta/metabolismo , Haptophyta/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Contaminantes Químicos del Agua/toxicidad , Microplásticos/toxicidad , Clorofila/metabolismo , Superóxido Dismutasa/metabolismo , Nanopartículas/toxicidad , Poliestirenos/toxicidad
2.
Environ Pollut ; 294: 118643, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34875264

RESUMEN

The effects of ocean acidification and solar radiation on marine organisms have received increasing attention. Coccolithophores are a major producer of dimethylsulfoniopropionate (DMSP), which is a precursor of dimethylsulfide (DMS), a volatile biogenic active gas related to climate. Here, we investigated the individual and combined effects of elevated CO2 and ultraviolet radiation (UVR) on growth, DMS, and DMSP production of Emiliania huxleyi. Elevated CO2 (1000 µatm, HC) decreased the cell concentration, DMS, and particulate DMSP (DMSPp) concentrations by 17%, 20%, and 13%, respectively, compared with ambient CO2 (400 µatm, LC) in the semi-continuous culture. The addition of UVA to photosynthetically active radiation (PAR) increased cell concentration of E. huxleyi by 16% on day 4, which may be due to the photorepair effects induced by UVA, and the effect was time-dependent. PAR + UVA and PAR + UVA + UVB exposure decreased cellular DMS by 25%-56%, and increased cellular DMSPp by 60%-130% compared with PAR on days 3-4. Cellular DMSPp followed the order: PAR + UVA > PAR + UVA + UVB > PAR, and HC had no significant effects on cellular DMSPp compared with LC in the combined experiment. These results aid our understanding of the effects of ocean acidification and UV radiation on the production of methyl sulfur compounds in the ocean.


Asunto(s)
Haptophyta , Compuestos de Sulfonio , Dióxido de Carbono , Concentración de Iones de Hidrógeno , Agua de Mar , Rayos Ultravioleta
3.
Environ Pollut ; 267: 115429, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32866870

RESUMEN

The effects of microplastics pollution on the marine ecosystem have aroused attention. Copepod grazing stimulates dimethylsulfide (DMS) release from dimethylsulfoniopropionate (DMSP) in phytoplankton, but the effect of microplastics exposure on DMS and DMSP production during copepod feeding has not yet been revealed. Here, we investigated the effects of polyethylene (PE) and polyamide-nylon 6 (PA 6) microplastics on ecotoxicity and DMS/DMSP production in the copepod Tigriopus japonicus. The microplastics had detrimental effects on feeding, egestion, reproduction, survival, and DMS and DMSP production in T. japonicus and presented significant dose-response relationships. The 24 h-EC50 for ingestion rates (IRs) of female T. japonicus exposed to PE and PA 6 were 57.6 and 58.9 mg L-1, respectively. In comparison, the body size of the copepods was not significantly affected by the microplastics during one generation of culture. Ingesting fluorescently labeled microplastics confirmed that microplastics were ingested by T. japonicus and adhered to the organs of the body surface. T. japonicus grazing promoted DMS release originating from degradation of DMSP in algal cells. Grazing-activated DMS production decreased because of reduced IR in the presence of microplastics. These results provide new insight into the biogeochemical cycle of sulfur during feeding in copepods exposed to microplastics.


Asunto(s)
Copépodos , Contaminantes Químicos del Agua , Animales , Ecosistema , Femenino , Fertilidad , Microplásticos , Plásticos/toxicidad , Contaminantes Químicos del Agua/toxicidad
4.
Rev Assoc Med Bras (1992) ; 66(7): 898-903, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32844929

RESUMEN

OBJECTIVE Long noncoding RNA neuroblastoma-associated transcript 1 (NBAT1) has been reported to be involved in cancer progression. However, the clinical significance of NBAT1 in non-small cell lung cancer (NSCLC) is still unclear. Our present research aimed to explore whether NBAT1 serves as a biomarker for NSCLC prognosis. METHODS The expression of NBAT1 was examined by RT-PCR in tissue samples of 162 NSCLC patients and was compared with the adjacent non-tumor lung specimens. Then the association between NBAT1 expression and clinical-pathological parameters was further evaluated. Survival analysis was performed using the Kaplan-Meier method. The prognostic significance of NBAT1 expression in NSCLC patients was explored by the use of univariate and multivariate analyses. RESULTS NBAT1 expression was prominently decreased in NSCLC tissues compared with matched normal lung specimens (p < 0.01). Moreover, survival analyses indicated that patients with low expression displayed dramatically decreased 5-year overall survival (p = 0.008). CONCLUSIONS NBAT1 expression might contribute to tumor progression and poor prognosis of NSCLC and might be a new therapeutic target in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neuroblastoma , ARN Largo no Codificante , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/genética , Pronóstico , ARN Largo no Codificante/metabolismo
5.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 66(7): 898-903, 2020. tab, graf
Artículo en Inglés | SES-SP, LILACS | ID: biblio-1136307

RESUMEN

SUMMARY OBJECTIVE Long noncoding RNA neuroblastoma-associated transcript 1 (NBAT1) has been reported to be involved in cancer progression. However, the clinical significance of NBAT1 in non-small cell lung cancer (NSCLC) is still unclear. Our present research aimed to explore whether NBAT1 serves as a biomarker for NSCLC prognosis. METHODS The expression of NBAT1 was examined by RT-PCR in tissue samples of 162 NSCLC patients and was compared with the adjacent non-tumor lung specimens. Then the association between NBAT1 expression and clinical-pathological parameters was further evaluated. Survival analysis was performed using the Kaplan-Meier method. The prognostic significance of NBAT1 expression in NSCLC patients was explored by the use of univariate and multivariate analyses. RESULTS NBAT1 expression was prominently decreased in NSCLC tissues compared with matched normal lung specimens (p < 0.01). Moreover, survival analyses indicated that patients with low expression displayed dramatically decreased 5-year overall survival (p = 0.008). CONCLUSIONS NBAT1 expression might contribute to tumor progression and poor prognosis of NSCLC and might be a new therapeutic target in NSCLC.


RESUMO OBJETIVO Há relatos de que o NBAT1 está associado à progressão do câncer. Contudo, o significado clínico do NBAT1 no câncer de pulmão de células não pequenas (NSCLC) ainda não está claro. O objetivo da nossa pesquisa foi explorar se NBAT1 serve como biomarcador para o prognóstico de NSCLC. MÉTODOS A expressão de NBAT1 foi examinada por RT-PCR em amostras de tecido de 162 pacientes com NSCLC e comparada a amostras adjacentes não tumorais de pulmão. Em seguida, a associação entre a expressão do NBAT1 e os parâmetros clínico-patológicos foi avaliada. A análise de sobrevivência foi realizada utilizando o método Kaplan-Meier. A significância prognóstica da expressão do NBAT1 em pacientes com NSCLC foi explorada através de análises univariadas e multivariadas. RESULTADOS A expressão do NBAT1 foi claramente diminuída nos tecidos de NSCLC em comparação aos espécimes normais dos pulmões (p<0,01). Além disso, as análises de sobrevivência indicaram que pacientes com baixa expressão apresentavam uma diminuição drástica da sobrevivência global em cinco anos (p=0,008). CONCLUSÃO A expressão do NBAT1 pode contribuir para a progressão tumoral e um prognóstico negativo do NSCLC e pode ser um novo alvo de terapia no NSCLC.


Asunto(s)
Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , ARN Largo no Codificante/metabolismo , Neoplasias Pulmonares/genética , Neuroblastoma , Pronóstico , Biomarcadores de Tumor , Regulación Neoplásica de la Expresión Génica , Estimación de Kaplan-Meier
6.
Fish Shellfish Immunol ; 24(5): 592-9, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18328731

RESUMEN

Oral delivery of plasmid DNA (pDNA) is a desirable approach for fish immunization in intensive culture. However, its effectiveness is limited because of possible degradation of pDNA in the fish's digestive system. In this report, alginate microspheres loaded with pDNA coding for fish lymphocystis disease virus (LCDV) and green fluorescent protein were prepared with a modified oil containing water (W/O) emulsification method. Yield, loading percent and encapsulation efficiency of alginate microspheres were 90.5%, 1.8% and 92.7%, respectively. The alginate microspheres had diameters of less than 10 microm, and their shape was spherical. As compared to sodium alginate, a remarkable increase of DNA-phosphodiester and DNA-phosphomonoester bonds was observed for alginate microspheres loaded with pDNA by Fourier transform infrared (FTIR) spectroscopic analysis. Agarose gel electrophoresis showed a little supercoiled pDNA was transformed to open circular and linear pDNA during encapsulation. The cumulative release of pDNA in alginate microspheres was or=0.3) for anti-LCDV antibody from week 3 to week 16 for fish orally vaccinated with alginate microspheres loaded with pDNA, in comparison with fish orally vaccinated with naked pDNA. Our results display that alginate microspheres obtained by W/O emulsification are promising carriers for oral delivery of pDNA. This encapsulation technique has the potential for DNA vaccine delivery applications due to its ease of operation, low cost and significant immune effect.


Asunto(s)
Infecciones por Virus ADN/veterinaria , Enfermedades de los Peces/inmunología , Lenguado/inmunología , Lenguado/virología , Iridoviridae/inmunología , Microesferas , Plásmidos/genética , Administración Oral , Alginatos , Animales , Formación de Anticuerpos , Infecciones por Virus ADN/inmunología , ADN Superhelicoidal , Enfermedades de los Peces/virología , Ácido Glucurónico , Proteínas Fluorescentes Verdes/metabolismo , Ácidos Hexurónicos , Iridoviridae/genética , Plásmidos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectroscopía Infrarroja por Transformada de Fourier , Vacunas de ADN/inmunología , Vacunas Virales/inmunología
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