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1.
Environ Pollut ; 351: 124084, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38697245

RESUMO

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.


Assuntos
Antioxidantes , Haptófitas , Espécies Reativas de Oxigênio , Sulfetos , Compostos de Sulfônio , Poluentes Químicos da Água , Antioxidantes/metabolismo , Compostos de Sulfônio/metabolismo , Haptófitas/crescimento & desenvolvimento , Haptófitas/metabolismo , Haptófitas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/toxicidade , Microplásticos/toxicidade , Clorofila/metabolismo , Superóxido Dismutase/metabolismo , Nanopartículas/toxicidade , Poliestirenos/toxicidade
2.
Front Immunol ; 14: 1165404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564658

RESUMO

Claudin 18.2 (CLDN18.2)-targeting chimeric antigen receptor (CAR)-modified T cells are one of the few cell therapies currently producing an impressive therapeutic effect in treating solid tumors; however, their long-term therapeutic efficacy is not satisfactory with a short duration of response. Transgenic expression of interleukin (IL)-15 has been reported to promote T-cell expansion, survival, and function and enhance the antitumor activity of engineered T cells in vitro and in vivo. Therefore, this study aimed to explore whether IL-15 modification would increase the antitumor activity of CLDN18.2-targeting CAR-modified T (CAR-T) cells in immunocompetent murine tumor models. CLDN18.2-specific CAR-T cells with (H9 CAR-IL15) or without transgenic IL-15 expression (H9 CAR) were generated by retroviral transduction of mouse splenic T cells. In vitro, compared with H9 CAR T cells, H9 CAR-IL15 T cells exhibited better expansion and viability in the absence of antigen stimulation, with a less differentiated and T-cell exhausted phenotype; although IL-15 modification did not affect the production of effector cytokines and cytotoxic activity in the short-term killing assay, it moderately improved the in vitro recursive killing activity of CAR-T cells against CLDN18.2-expressing tumor cells. In vivo, H9 CAR T cells showed no antitumor activity against CLDN18.2-expressing pancreatic tumors in immunocompetent mice without lymphodepleting pretreatment; however, H9 CAR-IL15 T cells produced significant tumor-suppressive effects. Furthermore, H9 CAR-IL15 T cells exhibited greater in vivo expansion and tumor infiltration when combined with lymphodepleting preconditioning, resulting in superior antitumor activity in two murine tumor models and a survival advantage in one tumor model. We further demonstrated that recurrent tumors following H9 CAR-IL15 T-cell therapy downregulated CLDN18.2 expression, suggesting immune escape through the selection of antigen-negative cells under persistent CAR-T-cell immune pressure. In conclusion, our findings provide preclinical evidence supporting the clinical evaluation of IL-15-expressing CLDN18.2 CAR-T cells in patients with CLDN18.2-positive tumors.


Assuntos
Interleucina-15 , Recidiva Local de Neoplasia , Camundongos , Animais , Interleucina-15/genética , Imunoterapia Adotiva/métodos , Linfócitos T , Claudinas/genética
3.
Ann Biomed Eng ; 51(4): 679-701, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36786901

RESUMO

Bowel cancer is a multifactorial disease arising from a combination of genetic predisposition and environmental factors. Detection of bowel cancer and its precursor lesions is predominantly performed by either visual inspection of the colonic mucosa during endoscopy or cross-sectional imaging. Most cases are diagnosed when the cancer is already at an advanced stage. These modalities are less reliable for detecting lesions at the earliest stages, when they are typically small or flat. Removal of lesions at the earliest possible stage reduces the risk of cancer death, which is largely due to a reduced risk of subsequent metastasis. In this review, we summarised the origin of bowel cancer and the mechanism of its metastasis. In particular, we reviewed a broad spectrum of literatures covering the biomechanics of bowel cancer and its measurement techniques that are pertinent to the successful development of a bowel cancer diagnostic device. We also reviewed existing bowel cancer diagnostic techniques that are available for clinical use. Finally, we outlined current clinical needs and highlighted the potential roles of medical robotics on early bowel cancer diagnosis.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Metástase Neoplásica
4.
Environ Pollut ; 294: 118643, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34875264

RESUMO

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.


Assuntos
Haptófitas , Compostos de Sulfônio , Dióxido de Carbono , Concentração de Íons de Hidrogênio , Água do Mar , Raios Ultravioleta
5.
Environ Pollut ; 267: 115429, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32866870

RESUMO

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.


Assuntos
Copépodes , Poluentes Químicos da Água , Animais , Ecossistema , Feminino , Fertilidade , Microplásticos , Plásticos/toxicidade , Poluentes Químicos da Água/toxicidade
6.
Rev Assoc Med Bras (1992) ; 66(7): 898-903, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32844929

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neuroblastoma , RNA Longo não Codificante , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Prognóstico , RNA Longo não Codificante/metabolismo
7.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 66(7): 898-903, 2020. tab, graf
Artigo em Inglês | Sec. Est. Saúde SP, LILACS | ID: biblio-1136307

RESUMO

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.


Assuntos
Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , RNA Longo não Codificante/metabolismo , Neoplasias Pulmonares/genética , Neuroblastoma , Prognóstico , Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , Estimativa de Kaplan-Meier
8.
J Food Sci ; 84(10): 3027-3036, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31529805

RESUMO

This study aimed to investigate the effect of Se (Selenium) treatment on nutritional quality in radish sprouts. The results showed that 15 µM sodium selenite significantly increased phenolics compounds, flavonoids compounds, anthocyanins, and some essential amino acid content, while improving the total antioxidant capacity of radish sprouts. Besides, the Se-enriched radish sprouts significantly alleviated the liver damage caused by carbon tetrachloride (CCl4 ) in mice and improved the antioxidant capacity of the liver in mice, whereas the Se-enriched radish sprouts alleviated the inflammatory reaction and apoptosis caused by CCl4 . These results imply that Se-enriched radish sprouts have a positive impact on mice with CCl4 -induced liver injury, and that in future Se-enriched radish sprouts could be developed into an effective food and health care product for the liver injury prevention. PRACTICAL APPLICATION: Because selenium is an essential trace element in the human body, selenium-enriched sprouts can help eliminate free radicals in the body, relieve aging, and selenium-deficient diseases. They are easy to grow and have low costs. Hence, selenium-enriched sprouts have a great potential of being widely consumed.


Assuntos
Tetracloreto de Carbono/efeitos adversos , Doença Hepática Crônica Induzida por Substâncias e Drogas/dietoterapia , Substâncias Protetoras/metabolismo , Raphanus/metabolismo , Selênio/metabolismo , Animais , Antocianinas/análise , Antocianinas/metabolismo , Antioxidantes/análise , Antioxidantes/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/prevenção & controle , Flavonoides/análise , Flavonoides/metabolismo , Humanos , Fígado/metabolismo , Masculino , Fenóis/análise , Fenóis/metabolismo , Substâncias Protetoras/análise , Raphanus/química , Raphanus/crescimento & desenvolvimento , Ratos , Ratos Wistar , Plântula/química , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Selênio/análise
9.
BMC Plant Biol ; 18(1): 227, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30305047

RESUMO

BACKGROUND: Hydrogen gas (H2) is the most abundant element in the universe, and has been reported to act as a novel beneficial gaseous molecule in plant adaptive responses. Radish sprouts are popular because they contain substantial amounts of antioxidants and health-promoting compounds, such as anthocyanin and glucosinolates. Although radish sprouts accumulated more anthocyanin under UV-A after treatment with hydrogen-rich water (HRW), the molecular mechanism responsible is still elusive. To explore these mechanisms, RNA-seq analysis was used. RESULTS: Four cDNA libraries from radish sprout hypocotyls were constructed, and a total of 14,564 differentially expressed genes (DEGs) were identified through pairwise comparisons. By Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, these unigenes were found to be implicated in light signal perception and transduction, starch and sucrose metabolism, photosynthesis, nitrogen metabolism and biosynthesis of secondary metabolites. The MYB-bHLH-WD40 complex accounted for the majority of the transcription factors found to be involved in anthocyanin biosynthesis, and levels of transcripts for this complex were in accordance with the anthocyanin concentrations observed. In addition, other transcription factors (such as NAC, bZIP and TCP) might participate in HRW-promoted anthocyanin biosynthesis. Furthermore, the signaling processes of plant hormones, MAPKs and Ca2+ might be involved in HRW-promoted anthocyanin biosynthesis under UV-A. The expression patterns of 16 selected genes were confirmed using qRT-PCR analysis. CONCLUSIONS: Taken together, the results of this study may expand our understanding of HRW-promoted anthocyanin accumulation under UV-A in radish sprouts.


Assuntos
Antocianinas/biossíntese , Hidrogênio/metabolismo , Raphanus/genética , Raphanus/metabolismo , Antocianinas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hipocótilo/genética , Hipocótilo/metabolismo , Anotação de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Raios Ultravioleta , Água/química , Água/metabolismo
10.
Sci Rep ; 7(1): 16366, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29180683

RESUMO

The soybean sprout is a nutritious and delicious vegetable that is rich in ascorbic acid (AsA). Hydrogen gas (H2) may have potential applications in the vegetable processing industry. To investigate whether H2 is involved in the regulation of soybean sprouts AsA biosynthesis under UV irradiation, we set 4 different treatments: white light(W), W+HRW, UV-A and UV-A+HRW. The results showed that H2 significantly blocked the UV-A-induced accumulation of ROS, decreased TBARS content and enhanced SOD and APX activity in soybean sprouts. We also observed that the UV-A induced accumulation of AsA was enhanced more intensely when co-treated with HRW. Molecular analyses showed that UV-A+HRW significantly up-regulated AsA biosynthesis and recycling genes compared to UV-A in soybean sprouts. These data demonstrate that the H2 positively regulates soybean sprouts AsA accumulation under UV-A and that this effect is mediated via the up-regulation of AsA biosynthesis and recycling genes.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Glycine max/fisiologia , Glycine max/efeitos da radiação , Hidrogênio/metabolismo , Raios Ultravioleta , Regulação da Expressão Gênica de Plantas , Estresse Oxidativo , Espécies Reativas de Oxigênio
11.
Sheng Wu Gong Cheng Xue Bao ; 32(3): 347-54, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27349117

RESUMO

To study the roles of glucosylglycerol phosphate synthase (Ggps) in glucosylglycerol (GG) and glycerol biosynthesis, we over-expressed Ggps from either Synechocystis sp. PCC 6803 or Synechococcus sp. PCC 7002 in a Synechocystis strain with a high GG titer, and determined the GG and glycerol accumulation in the resultant mutants grown under different NaCl-stress conditions. Ion chromatography results revealed that GG yield was not improved, but glycerol production was significantly enhanced by over-expression of Ggps from Synechocystis sp. PCC 6803 (6803ggpS). In addition, increasing the NaCl concentration of medium from 600 to 900 mmol/L led to a further 75% increase of glycerol accumulation in the mutant strain with 6803ggpS over-expression. These findings show the role of ggpS in driving the carbon flux to the glycerol biosynthesis pathway, and will be helpful for further improvement of GG and glycerol production in Synechocystis.


Assuntos
Proteínas de Bactérias/metabolismo , Glucosídeos/biossíntese , Glucosiltransferases/metabolismo , Glicerol/metabolismo , Synechocystis/metabolismo , Meios de Cultura , Microbiologia Industrial , Cloreto de Sódio , Synechococcus/enzimologia , Synechocystis/enzimologia
13.
Fish Shellfish Immunol ; 30(1): 109-17, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20920584

RESUMO

In order to protect DNA vaccine against degradation in alimentary tract of fish, poly(lactic-co-glycolic acid) (PLGA) nanoparticles encapsulating vaccine were prepared using W/O/W emulsification combined with spray drying technique in our laboratory. The characteristics of PLGA nanoparticles were described as follows: (1) shape, spherical; (2) size, <500 nm; (3) yield, ∼96.2%; loading percentage, ∼0.5%; encapsulation efficiency, ∼63.7%; supercoiled conformation percentage, ∼65%; (4) release dynamics, gradual release. In vitro transfection in SISK cells showed that PLGA nanoparticles could be utilized to transfect eukaryotes. After oral administration, FITC-labeled PLGA nanoparticles were detected in blood of fish, and RNA containing major capsid protein (MCP) gene information existed in various tissues of fish 10-90 days. In addition, the analysis of immune parameters in sera of treatment fish showed that: (1) infection rate of LCDV post-challenge, ∼16.7%; (2) prophenoloxidase, superoxide dismutase, respiratory burst, lysozyme and antibody levels, increased significantly (p<0.05); (3) activities of serum complement, changed a little (p>0.05). Pearson's correlation displayed that correlation of immune factors mentioned above (not including serum complement) were all positive for fish vaccinated. The data in this study suggested that PLGA nanoparticles were promising carriers for plasmid DNA vaccine and might be used to vaccinate fish by oral approach.


Assuntos
Doenças dos Peixes/prevenção & controle , Linguado , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Vacinas de DNA/imunologia , Vacinas Virais/imunologia , Animais , Bass , Linhagem Celular , Infecções por Vírus de DNA/prevenção & controle , Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/virologia , Iridoviridae/imunologia , Rim/citologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
14.
J Photochem Photobiol B ; 97(3): 152-60, 2009 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-19818642

RESUMO

Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina.


Assuntos
Aclimatação/efeitos da radiação , Antioxidantes/metabolismo , Clorófitas/efeitos da radiação , Raios Ultravioleta , Ácido Ascórbico/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Clorófitas/metabolismo , Clorófitas/ultraestrutura , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidase/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Vet Immunol Immunopathol ; 126(3-4): 220-9, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18722672

RESUMO

Oral DNA-based immunotherapy is a new treatment option for fish immunisation in intensive culture. However, because of the existence of the nucleases and severe gastrointestinal conditions, DNA-based vaccines can be hydrolyzed or denatured. In our laboratory, a plasmid DNA (pDNA) containing major capsid protein (MCP) gene of lymphocystis disease virus (LCDV) was prepared, and then pDNA was encapsulated in chitosan microspheres through an emulsion-based methodology. The yield, loading percent and encapsulation efficiency of microspheres were 93.6%, 0.3% and 94.5%, respectively. Scanning electron microscopy (SEM) showed that pDNA-loaded microspheres yielded a spherical shape with smooth surfaces. The disproportion of super-coiled to open circle and linear pDNA suggested that high transfection efficiencies of pDNA in microspheres were retained. The cumulative release of pDNA showed that chitosan microspheres were resistant to degradation in simulated gastrointestinal tract environment. The release profile at PBS buffer (pH 7.4) displayed that pDNA-loaded chitosan microspheres had a release up to 42 days after intestinal imbibition. RT-PCR showed that RNA containing information of MCP gene existed in various tissues 10-90 days post-vaccination. SDS-PAGE and immunofluorescent images indicated that pDNA expressed MCP in tissues of fish 10-90 days after oral administration. In addition, indirect ELISA displayed that the immune responses of sera were positive (O.D.> or =0.3) from week 1 to week 16 for fish vaccinated with microspheres, in comparison with fish vaccinated with naked pDNA. Data obtained suggested that chitosan microspheres were promising carriers for oral pDNA vaccine. Because this encapsulation technique was easy to operate and immunisation efficacy of microspheres loaded with pDNA was significant, it had potential to be used in drug delivery applications.


Assuntos
Quitosana/imunologia , Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/prevenção & controle , Linguado , Imunoterapia/veterinária , Iridoviridae/imunologia , Microesferas , Vacinas de DNA/imunologia , Animais , Proteínas do Capsídeo/genética , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/prevenção & controle , Eletroforese em Gel de Poliacrilamida/veterinária , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Imunofluorescência/veterinária , Imunoterapia/métodos , Microscopia Eletrônica de Varredura/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
16.
Int Immunopharmacol ; 8(6): 900-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18442796

RESUMO

Nucleic acid-based immunotherapy is a new treatment option for fish immunisation in intensive culture. However, DNA-based vaccines would be hydrolyzed or denaturized because of the existence of nucleases and severe gastrointestinal conditions. Poly(DL-lactide-co-glycolide) (PLGA) microcapsules, loaded with plasmid DNA (pDNA) against lymphocystis disease virus (LCDV), were prepared by modified water in oil in water (W/O/W) double emulsion method in our laboratory. Encapsulation efficiency, loading percent and diameter of microcapsules were 78-88%, 0.5-0.7% and less than 10 mum, respectively. In simulated gastric fluid (SGF), less than 10% of pDNA was released from microcapsules in 12 h, and about 6.5% of pDNA was released in 12 h in simulated intestinal fluid (SIF). The content of the supercoiled of pDNA in microcapsules and control was 80% and 89% respectively, which indicated that a little supercoiled pDNA degradation occurred during encapsulation. RT-PCR showed that lots of RNA containing information of MCP gene existed in all tissues of fish vaccinated with microcapsules 10-90 days after oral administration. SDS-PAGE and immunoblots, as well as immunofluorescence images, displayed that major capsid protein (MCP) of LCDV was expressed in tissues of fish vaccinated with pDNA-loaded microcapsules. In addition, indirect enzyme-linked immunosorbent assay (ELISA) showed that the immune responses of sera were positive (O.D> or =0.3) from week 1 to week 24 for fish vaccinated with microcapsules, in comparison with fish vaccinated with naked pDNA. Our results suggested that PLGA microcapsules were promising oral carriers for pDNA delivery. This encapsulation technique had potential for drug delivery applications due to its ease of operation and notable immunisation efficacy.


Assuntos
Proteínas do Capsídeo/imunologia , Infecções por Vírus de DNA/veterinária , Linguado/imunologia , Iridoviridae/imunologia , Vacinação/veterinária , Vacinas de DNA/administração & dosagem , Vacinas Virais/administração & dosagem , Administração Oral , Animais , Cápsulas , Infecções por Vírus de DNA/imunologia , Infecções por Vírus de DNA/prevenção & controle , Doenças dos Peixes/imunologia , Doenças dos Peixes/prevenção & controle , Iridoviridae/isolamento & purificação , Ácido Láctico , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vacinação/métodos , Vacinas de DNA/imunologia , Vacinas de DNA/metabolismo , Vacinas Virais/imunologia
17.
Fish Shellfish Immunol ; 24(5): 592-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18328731

RESUMO

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.


Assuntos
Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/imunologia , Linguado/imunologia , Linguado/virologia , Iridoviridae/imunologia , Microesferas , Plasmídeos/genética , Administração Oral , Alginatos , Animais , Formação de Anticorpos , Infecções por Vírus de DNA/imunologia , DNA Super-Helicoidal , Doenças dos Peixes/virologia , Ácido Glucurônico , Proteínas de Fluorescência Verde/metabolismo , Ácidos Hexurônicos , Iridoviridae/genética , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Infravermelho com Transformada de Fourier , Vacinas de DNA/imunologia , Vacinas Virais/imunologia
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