Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Br J Cancer ; 123(3): 495, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32393850

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
BMC Cancer ; 20(1): 294, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264844

RESUMO

BACKGROUND: Polymorphisms in MTHFR gene influence risk and overall survival of patients with brain tumor. Global genomic DNA (gDNA) methylation profile from tumor tissues is replicated in peripheral leukocytes. This study aimed to draw a correlation between rs1801133 MTHFR variants, gDNA methylation and overall survival of patients with recurrent glioblastoma (rGBM) under perillyl alcohol (POH) treatment. METHODS: gDNA from whole blood was extracted using a commercially available kit (Axygen) and quantified by spectrophotometry. Global gDNA methylation was determined by ELISA and rs1801133 polymorphism by PCR-RFLP. Statistical analysis of gDNA methylation profile and rs1801133 variants included Mann-Whitney, Kruskal-Wallis, Spearman point-biserial correlation tests (SPSS and Graphpad Prism packages; significant results for effect size higher than 0.4). Prognostic value of gDNA methylation and rs1801133 variants considered survival profiles at 25 weeks of POH treatment, having the date of protocol adhesion as starting count and death as the final event. RESULTS: Most rGBM patients showed global gDNA hypomethylation (median = 31.7%) and a significant, moderate and negative correlation between TT genotype and gDNA hypomethylation (median = 13.35%; rho = - 0.520; p = 0.003) compared to CC variant (median = 32.10%), which was not observed for CT variant (median = 33.34%; rho = - 0.289; p = 0.06). gDNA hypermethylated phenotype (median = 131.90%) exhibited significant, moderate and negative correlations between TT genotype (median = 112.02%) and gDNA hypermethylation levels when compared to CC (median = 132.45%; rho = - 0,450; p = 0.04) or CT (median = 137.80%; rho = - 0.518; p = 0.023) variants. TT variant of rs1801133 significantly decreased gDNA methylation levels for both patient groups, when compared to CC (d values: hypomethylated = 1.189; hypermethylated = 0.979) or CT (d values: hypomethylated = 0.597; hypermethylated = 1.167) variants. Positive prognostic for rGBM patients may be assigned to gDNA hypermethylation for survivors above 25 weeks of treatment (median = 88 weeks); and TT variant of rs1801133 regardless POH treatment length. CONCLUSION: rGBM patients under POH-based therapy harboring hypermethylated phenotype and TT variant for rs1801133 had longer survival. Intranasal POH therapy mitigates detrimental effects of gDNA hypomethylation and improved survival of patients with rGBM harboring TT mutant variant for MTHFR rs1801133 polymorphism. TRIAL REGISTRATION: CONEP -9681- 25,000.009267 / 2004. Registered 12th July, 2004.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Metilação de DNA , Glioblastoma/tratamento farmacológico , Leucócitos/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Monoterpenos/uso terapêutico , Recidiva Local de Neoplasia , Administração Intranasal , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Monoterpenos/administração & dosagem , Polimorfismo de Nucleotídeo Único , Adulto Jovem
3.
Br J Cancer ; 120(1): 88-96, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30377341

RESUMO

BACKGROUND: Pancreatic cancer (PC) hijacks innate cellular processes to promote cancer growth. We hypothesized that PC exploits PD-1/PD-L1 not only to avoid immune responses, but to directly enhance growth. We also hypothesized that immune checkpoint inhibitors (ICIs) have direct cytotoxicity in PC. We sought to elucidate therapeutic targeting of PD-1/PD-L1. METHODS: PD-1 was assessed in PC cells, patient-derived organoids (PDOs), and clinical tissues. Then, PC cells were exposed to PD-L1 to evaluate proliferation. To test PD-1/PD-L1 signaling, cells were exposed to PD-L1 and MAPK was examined. Radio-immunoconjugates with anti-PD-1 drugs were developed to test uptake in patient-derived tumor xenografts (PDTXs). Next, PD-1 function was assessed by xenografting PD-1-knockdown cells. Finally, PC models were exposed to ICIs. RESULTS: PD-1 expression was demonstrated in PCs. PD-L1 exposure increased proliferation and activated MAPK. Imaging PDTXs revealed uptake of radio-immunoconjugates. PD-1 knockdown in vivo revealed 67% smaller volumes than controls. Finally, ICI treatment of both PDOs/PDTXs demonstrated cytotoxicity and anti-MEK1/2 combined with anti-PD-1 drugs produced highest cytotoxicity in PDOs/PDTXs. CONCLUSIONS: Our data reveal PCs innately express PD-1 and activate druggable oncogenic pathways supporting PDAC growth. Strategies directly targeting PC with novel ICI regimens may work with adaptive immune responses for optimal cytotoxicity.


Assuntos
Antígeno B7-H1/imunologia , Imunoterapia , Neoplasias Pancreáticas/tratamento farmacológico , Receptor de Morte Celular Programada 1/imunologia , Animais , Antígeno B7-H1/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Organoides/efeitos dos fármacos , Organoides/imunologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Cultura Primária de Células , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Surg Oncol ; 116(1): 7-15, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28605029

RESUMO

The tumor microenvironment in pancreatic cancer is a complex balance of pro- and anti-tumor components. The dense desmoplasia consists of immune cells, extracellular matrix, growth factors, cytokines, and cancer associated fibroblasts (CAF) or pancreatic stellate cells (PSC). There are a multitude of targets including hyaluronan, angiogenesis, focal adhesion kinase (FAK), connective tissue growth factor (CTGF), CD40, chemokine (C-X-C motif) receptor 4 (CXCR-4), immunotherapy, and Vitamin D. The developing clinical therapeutics will be reviewed.


Assuntos
Neoplasias Pancreáticas/patologia , Microambiente Tumoral , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Inibidores da Angiogênese/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Fibroblastos Associados a Câncer/patologia , Carcinogênese , Transformação Celular Neoplásica , Ensaios Clínicos como Assunto , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Proteínas Hedgehog/antagonistas & inibidores , Humanos , Ácido Hialurônico/metabolismo , Imunoterapia , Macrófagos/patologia , Células Mieloides/patologia , Neutrófilos/patologia , Osteonectina/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Células Estreladas do Pâncreas/patologia , Vitamina D/farmacologia
5.
Biochem Biophys Res Commun ; 457(3): 404-11, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25582774

RESUMO

Estrogen (E2) supports breast cancer cell growth but suppresses invasiveness and both actions are antagonized by anti-estrogens. As a consequence, anti-estrogen treatment may increase the invasive potential of estrogen receptor (ER)+ tumor cell sub-populations that are endocrine resistant due to HER2 amplification. Either transactivation or transrepression by E2/ER could lead to both up- and down-regulation of many genes. Inhibition of the transactivation function of ER is adequate to inhibit E2-dependent growth. However, the impact of inhibiting E2-dependent transactivation vs. transrepression by ER on regulation of invasiveness by E2 is less clear. Here we dissect the roles of ER-mediated transactivation and transrepression in the regulation of invasiveness of ER+/HER2+ breast cancer cells by E2. Knocking down the general ER co-activators CBP and p300 prevented activation by E2 of its classical target genes but did not interfere with the ability of E2 to repress its direct target genes known to support invasiveness and tumor progression; there was also no effect on invasiveness or the ability of E2 to regulate invasiveness. On the other hand, overexpression of a co-repressor binding site mutant of ER (L372R) prevented E2-dependent transrepression but not transactivation. The mutant ER abrogated the ability of E2 to suppress invasiveness. E2 can partially down-regulate HER2 but knocking down HER2 below E2-regulated levels did not affect invasiveness or the ability of E2 to regulate invasiveness, although it did inhibit growth. Therefore, in ER+/HER2+ cells, the E2-dependent transrepression by ER rather than its transactivation function is critical for regulation of invasiveness and this is independent of HER2 regulation by E2. The findings suggest that selective inhibitors of transactivation by ER may be more beneficial in reducing tumor progression than conventional anti-estrogens that also antagonize E2-dependent transrepression.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Estradiol/metabolismo , Estradiol/farmacologia , Moduladores de Receptor Estrogênico/farmacologia , Feminino , Expressão Gênica , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/fisiopatologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/metabolismo , Ativação Transcricional
6.
Proteomics ; 14(7-8): 904-12, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24678036

RESUMO

The main goal of this work is to evaluate some differential protein species in transgenic (T) and nontransgenic (NT) Arabidopsis thaliana plants after their cultivation in the presence or absence of sodium selenite. The transgenic line was obtained through insertion of CaMV 35S controlling nptII gene. Comparative proteomics through 2D-DIGE is carried out in four different groups (NT × T; NT × Se-NT (where Se is selenium); Se-NT × Se-T, and T × Se-T). Although no differential proteins are achieved in the T × Se-T group, for the others, 68 differential proteins (by applying a regulation factor ≥1.5) are achieved, and 27 of them accurately characterized by ESI-MS/MS. These proteins are classified into metabolism, energy, signal transduction, disease/defense categories, and some of them are involved in the glycolysis pathway-Photosystems I and II and ROS combat. Additionally, laser ablation imaging is used for evaluating the Se and sulfur distribution in leaves of different groups, corroborating some results obtained and related to proteins involved in the glycolysis pathway. From these results, it is possible to conclude that the genetic modification also confers to the plant resistance to oxidative stress.


Assuntos
Arabidopsis/genética , Folhas de Planta/genética , Proteômica , Selenito de Sódio/administração & dosagem , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Eletroforese em Gel Bidimensional/métodos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lasers , Imagem Molecular/métodos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/biossíntese , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
7.
BMC Plant Biol ; 14: 301, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25407319

RESUMO

BACKGROUND: Eucalyptus species are the most widely planted hardwood species in the world and are renowned for their rapid growth and adaptability. In Brazil, one of the most widely grown Eucalyptus cultivars is the fast-growing Eucalyptus urophylla x Eucalyptus grandis hybrid. In a previous study, we described a chemical characterization of these hybrids when subjected to flavonoid supplementation on 2 distinct timetables, and our results revealed marked differences between the wood composition of the treated and untreated trees. RESULTS: In this work, we report the transcriptional responses occurring in these trees that may be related to the observed chemical differences. Gene expression was analysed through mRNA-sequencing, and notably, compared to control trees, the treated trees display differential down-regulation of cell wall formation pathways such as phenylpropanoid metabolism as well as differential expression of genes involved in sucrose, starch and minor CHO metabolism and genes that play a role in several stress and environmental responses. We also performed enzymatic hydrolysis of wood samples from the different treatments, and the results indicated higher sugar contents and glucose yields in the flavonoid-treated plants. CONCLUSIONS: Our results further illustrate the potential use of flavonoids as a nutritional complement for modifying Eucalyptus wood, since, supplementation with flavonoids alters its chemical composition, gene expression and increases saccharification probably as part of a stress response.


Assuntos
Eucalyptus/efeitos dos fármacos , Flavonoides/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Parede Celular/química , Parede Celular/metabolismo , Regulação para Baixo , Eucalyptus/química , Eucalyptus/genética , Eucalyptus/metabolismo , Lignina/química , Lignina/metabolismo , Árvores , Madeira/química , Madeira/efeitos dos fármacos , Madeira/genética , Madeira/metabolismo
8.
BMC Plant Biol ; 14: 256, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25260963

RESUMO

BACKGROUND: Nitrogen (N) is a main nutrient required for tree growth and biomass accumulation. In this study, we analyzed the effects of contrasting nitrogen fertilization treatments on the phenotypes of fast growing Eucalyptus hybrids (E. urophylla x E. grandis) with a special focus on xylem secondary cell walls and global gene expression patterns. RESULTS: Histological observations of the xylem secondary cell walls further confirmed by chemical analyses showed that lignin was reduced by luxuriant fertilization, whereas a consistent lignin deposition was observed in trees grown in N-limiting conditions. Also, the syringyl/guaiacyl (S/G) ratio was significantly lower in luxuriant nitrogen samples. Deep sequencing RNAseq analyses allowed us to identify a high number of differentially expressed genes (1,469) between contrasting N treatments. This number is dramatically higher than those obtained in similar studies performed in poplar but using microarrays. Remarkably, all the genes involved the general phenylpropanoid metabolism and lignin pathway were found to be down-regulated in response to high N availability. These findings further confirmed by RT-qPCR are in agreement with the reduced amount of lignin in xylem secondary cell walls of these plants. CONCLUSIONS: This work enabled us to identify, at the whole genome level, xylem genes differentially regulated by N availability, some of which are involved in the environmental control of xylogenesis. It further illustrates that N fertilization can be used to alter the quantity and quality of lignocellulosic biomass in Eucalyptus, offering exciting prospects for the pulp and paper industry and for the use of short coppices plantations to produce second generation biofuels.


Assuntos
Parede Celular/metabolismo , Eucalyptus/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lignina/metabolismo , Nitrogênio/farmacologia , Xilema/efeitos dos fármacos , Eucalyptus/genética , Eucalyptus/metabolismo , Fertilizantes , Fenótipo , Árvores , Madeira/efeitos dos fármacos , Madeira/metabolismo , Xilema/genética , Xilema/metabolismo
9.
PLoS One ; 19(5): e0300310, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776274

RESUMO

Gravity is one of the most constant environmental factors across Earth's evolution and all organisms are adapted to it. Consequently, spatial exploration has captured the interest in studying the biological changes that physiological alterations are caused by gravity. In the last two decades, epigenetics has explained how environmental cues can alter gene functions in organisms. Although many studies addressed gravity, the underlying biological and molecular mechanisms that occur in altered gravity for those epigenetics-related mechanisms, are mostly inexistent. The present study addressed the effects of hypergravity on development, behavior, gene expression, and most importantly, on the epigenetic changes in a worldwide animal model, the zebrafish (Danio rerio). To perform hypergravity experiments, a custom-centrifuge simulating the large diameter centrifuge (100 rpm ~ 3 g) was designed and zebrafish embryos were exposed during 5 days post fertilization (dpf). Results showed a significant decrease in survival at 2 dpf but no significance in the hatching rate. Physiological and morphological alterations including fish position, movement frequency, and swimming behavior showed significant changes due to hypergravity. Epigenetic studies showed significant hypermethylation of the genome of the zebrafish larvae subjected to 5 days of hypergravity. Downregulation of the gene expression of three epigenetic-related genes (dnmt1, dnmt3, and tet1), although not significant, was further observed. Taken altogether, gravity alterations affected biological responses including epigenetics in fish, providing a valuable roadmap of the putative hazards of living beyond Earth.


Assuntos
Epigênese Genética , Hipergravidade , Peixe-Zebra , Animais , Peixe-Zebra/genética , Metilação de DNA , Larva/genética , Larva/crescimento & desenvolvimento , Embrião não Mamífero/metabolismo
10.
Biotechniques ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602382

RESUMO

Molecular techniques have revolutionized tuberculosis (TB) diagnosis by offering a faster and more sensitive approach, detecting Mycobacterium tuberculosis (Mtb) DNA directly from samples. Single-tube nested PCR (STNPCR) combines two PCR reactions with separate oligonucleotide sets in a single tube. Moreover, colorimetric methods in PCR products have been studied for pathogen detection. Thus, this study aimed to establish a novel system based on colorimetric STNPCR for Mtb detection using microtiter plates with IS6110-amplified fragments. The results showed a general colorimetric STNPCR detection limit of 1 pg/µl. Its general sensitivity and specificity were 76.62 and 60.53%, respectively, with kappa index agreement of 0.166.

11.
BMC Genomics ; 14: 201, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23521840

RESUMO

BACKGROUND: Eucalyptus is one of the most important sources of industrial cellulose. Three species of this botanical group are intensively used in breeding programs: E. globulus, E. grandis and E. urophylla. E. globulus is adapted to subtropical/temperate areas and is considered a source of high-quality cellulose; E. grandis grows rapidly and is adapted to tropical/subtropical climates; and E. urophylla, though less productive, is considered a source of genes related to robustness. Wood, or secondary xylem, results from cambium vascular differentiation and is mostly composed of cellulose, lignin and hemicelluloses. In this study, the xylem transcriptomes of the three Eucalyptus species were investigated in order to provide insights on the particularities presented by each of these species. RESULTS: Data analysis showed that (1) most Eucalyptus genes are expressed in xylem; (2) most genes expressed in species-specific way constitutes genes with unknown functions and are interesting targets for future studies; (3) relevant differences were observed in the phenylpropanoid pathway: E. grandis xylem presents higher expression of genes involved in lignin formation whereas E. urophylla seems to deviates the pathway towards flavonoid formation; (4) stress-related genes are considerably more expressed in E. urophylla, suggesting that these genes may contribute to its robustness. CONCLUSIONS: The comparison of these three transcriptomes indicates the molecular signatures underlying some of their distinct wood characteristics. This information may contribute to the understanding of xylogenesis, thus increasing the potential of genetic engineering approaches aiming at the improvement of Eucalyptus forest plantations productivity.


Assuntos
Eucalyptus/genética , Transcriptoma , Parede Celular/genética , Parede Celular/metabolismo , Mapeamento de Sequências Contíguas , Bases de Dados Factuais , Eucalyptus/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Xilema/genética , Xilema/metabolismo
12.
J Invertebr Pathol ; 112(1): 68-73, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23022573

RESUMO

Prior to 2004, Colombian shrimp farming benefited from a selection program in which Penaeus vannamei stocks were developed with resistance to Taura syndrome disease (TS). However since 2004, TS reappeared as a significant disease. In 2010, an apparently new strain of TSV (designated as CO 10) was collected in Colombia. Its genome was sequenced and compared with six other fully sequenced isolates. This analysis revealed that the TSV CO 10 is closely related to the isolates from Hawaii and Venezuela. Phylogenetic analysis based on capsid protein 2 (CP2) region from 59 TSV isolates shows that the recent Colombian isolates (2006-2010) form a new cluster and differ from the previous Colombia isolates (1994-1998) by 4% in nucleotide sequence. The virulence of this CO 10 isolate was similar to a Belize TSV determined through experimental infection in P. vannamei showing 100% mortalities and similar survival curves. By RT-qPCR for TSV, the viral loads were also close in the infected shrimp from both CO 10 and Belize at the order of 1×10(10) copies per µl RNA. To develop TSV-resistant lines, the candidate shrimp should be challenged with virus strains that have been isolated most recently from the regions where they will be cultured. This study suggests that the TSV present in Colombian shrimp farms during the last 5 years is a new TSV strain with high virulence.


Assuntos
Dicistroviridae/genética , Penaeidae/virologia , Animais , Aquicultura , Sequência de Bases , Colômbia , Dicistroviridae/patogenicidade , Dicistroviridae/fisiologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Virulência
13.
Dis Aquat Organ ; 106(1): 31-7, 2013 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-24062550

RESUMO

Aquaculture of cobia has gained popularity in the last decade, and this species is now farmed in several countries in Latin America and Asia. Despite recent improvement in production techniques that allowed the expansion of the industry, little is known about the diseases that affect cobia during the larviculture stage. In this article we investigated the cause of mass mortalities occurring 13-20 d post-hatching in 3 cycles of cobia larviculture. Wet mounts from diseased larvae gills revealed the presence of cyst-like basophilic inclusions. DNA from the cysts was extracted and PCR amplified using the 16S rRNA gene universal primers for prokaryotes. The amplified products were sequenced and analyzed using BLAST, finding a similarity of 99% with Endozoicomonas elysicola, a Gram-negative bacterium. Confirmation of E. elysicola was conducted by designing a specific probe for in situ hybridization. Specific primers were also designed for diagnostic purposes. This is the first report of epitheliocystis in cobia larvae and also the first report of E. elysicola as an epitheliocystis-causing agent.


Assuntos
Infecções Bacterianas/veterinária , Doenças dos Peixes/microbiologia , Gammaproteobacteria/isolamento & purificação , Perciformes , Animais , Infecções Bacterianas/microbiologia , Surtos de Doenças , Larva
14.
Rev Aquac ; 15(2): 491-535, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38504717

RESUMO

Disease and parasitism cause major welfare, environmental and economic concerns for global aquaculture. In this review, we examine the status and potential of technologies that exploit genetic variation in host resistance to tackle this problem. We argue that there is an urgent need to improve understanding of the genetic mechanisms involved, leading to the development of tools that can be applied to boost host resistance and reduce the disease burden. We draw on two pressing global disease problems as case studies-sea lice infestations in salmonids and white spot syndrome in shrimp. We review how the latest genetic technologies can be capitalised upon to determine the mechanisms underlying inter- and intra-species variation in pathogen/parasite resistance, and how the derived knowledge could be applied to boost disease resistance using selective breeding, gene editing and/or with targeted feed treatments and vaccines. Gene editing brings novel opportunities, but also implementation and dissemination challenges, and necessitates new protocols to integrate the technology into aquaculture breeding programmes. There is also an ongoing need to minimise risks of disease agents evolving to overcome genetic improvements to host resistance, and insights from epidemiological and evolutionary models of pathogen infestation in wild and cultured host populations are explored. Ethical issues around the different approaches for achieving genetic resistance are discussed. Application of genetic technologies and approaches has potential to improve fundamental knowledge of mechanisms affecting genetic resistance and provide effective pathways for implementation that could lead to more resistant aquaculture stocks, transforming global aquaculture.

15.
J Exp Bot ; 63(1): 503-15, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21963612

RESUMO

Glutaredoxins (GRXs) belong to the antioxidant and signalling network involved in the cellular response to oxidative stress in bacterial and eukaryotic cells. In spite of the high number of GRX genes in plant genomes, the biological functions and physiological roles of most of them remain unknown. Here the functional characterization of the Arabidopsis GRXS13 gene (At1g03850), that codes for two CC-type GRX isoforms, is reported. The transcript variant coding for the GRXS13.2 isoform is predominantly expressed under basal conditions and is the isoform that is induced by photooxidative stress. Transgenic lines where the GRXS13 gene has been knocked down show increased basal levels of superoxide radicals and reduced plant growth. These lines also display reduced tolerance to methyl viologen (MeV) and high light (HL) treatments, both conditions of photooxidative stress characterized by increased production of superoxide ions. Consistently, lines overexpressing the GRXS13.2 variant show reduced MeV- and HL-induced damage. Alterations in GRXS13 expression also affect superoxide levels and the ascorbate/dehydroascorbate ratio after HL-induced stress. These results indicate that GRXS13 gene expression is critical for limiting basal and photooxidative stress-induced reactive oxygen species (ROS) production. Together, these results place GRXS13.2 as a member of the ROS-scavenging/antioxidant network that shows a particularly low functional redundancy in the Arabidopsis GRX family.


Assuntos
Arabidopsis/fisiologia , Glutarredoxinas/fisiologia , Estresse Oxidativo , Fotoquímica , Arabidopsis/genética , Sequência de Bases , Primers do DNA , Plantas Geneticamente Modificadas
16.
J Insect Sci ; 12: 110, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23438175

RESUMO

The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and southern Chile. Aphids were genotyped by cross-species amplification of four microsatellite loci from other aphid species. In addition, the aphid borne virus Strawberry mild yellow edge virus was confirmed in F. chiloensis plants by double-antibody sandwich ELISA and RT-PCR. Genetic variability and structure of the aphid populations was assessed from the geo-referenced individuals through AMOVA and a Bayesian assignment test. The presence of C. fragaefolii, during the two-year study was detected in only four of the seven sites (Curepto, Contulmo, Chilián and Cucao). Genetic variation among these populations reached 19% of the total variance. When assigning the individuals to groups, these were separated in three genetic clusters geographically disjunct. Of the seven sampled sites, six were positive for the virus by RT-PCR, and five by double-antibody sandwich ELISA . The incidence of the virus ranged from 0-100%. Presence of the virus corresponded with the presence of the aphid in all but two sites (Chilian and Vilches). The greatest incidence of Strawberry mild yellow edge virus was related to the abundance of aphids. On the other hand, sequences of the coat protein gene of the different virus samples did not show correspondence with either the genetic groups of the aphids or the sampling sites. The genetic structure of aphids could suggest that dispersal is mainly through human activities, and the spread to natural areas has not yet occurred on a great scale.


Assuntos
Afídeos/genética , Afídeos/virologia , Fragaria/virologia , Genes de Insetos , Doenças das Plantas/virologia , Potexvirus/genética , Análise de Variância , Animais , Afídeos/fisiologia , Teorema de Bayes , Chile , Ensaio de Imunoadsorção Enzimática , Feminino , Cadeia Alimentar , Fragaria/crescimento & desenvolvimento , Fluxo Gênico , Variação Genética , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Estações do Ano
17.
Plast Reconstr Surg Glob Open ; 10(2): e4137, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35233337

RESUMO

Biopolymer-induced human adjuvant disease (BHAD) is a chronic clinical condition that requires surgical intervention, regardless of the presence of symptoms, to minimize the risk of functional, aesthetic, and systemic sequelae and the development of conditions simulating autoimmune disease. We propose a classification for BHAD on the basis of course of the disease, which will make it possible to assess the damage and difficulty in patients, leading to a more appropriate therapeutic approach. METHODS: A protocol study was implemented. A casuistry of patients with a diagnosis of autoimmune/inflammatory syndrome induced by adjuvants was taken into account according to the Shoenfeld criteria. Qualitative variables were analyzed through frequencies and percentages, and quantitative variables were analyzed with measures of central tendency and dispersion. The diagnostic validity of the signs and symptoms was analyzed using some paraclinical tests. RESULTS: A total of 190 patients diagnosed with autoimmune/inflammatory syndrome induced by adjuvants with biopolymers in the buttocks and who underwent a surgical procedure by the open, masked technique between January 2017 and December 2020 were selected. Considering each sign and symptom, the location of the biopolymers in different planes, and pathophysiology of the clinical course of the disease, a classification was proposed that takes into account diagnostic imaging findings, local clinical signs, systemic symptoms, systemic clinical signs, and autoimmune markers. CONCLUSION: Some signs associated with biomarkers with sensitivity and specificity values can influence the pretest decision to request paraclinicals, improving the diagnostic probability and cost effectiveness in these patients.

18.
Access Microbiol ; 4(8): acmi000405, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36133177

RESUMO

Microbiome components and bacterial isolates related to healthy and epitheliocystis states in aquaculture cycles of cobia fish were studied. We detected well-defined 16S rRNA amplicon gene sequence variants showing differential abundance in healthy or diseased cycles. Isolation trials were performed, and experimental tests were used to determine probiotic potential of the bacterial strains obtained from water, tissues or live food used in this aquaculture model. The taxonomic affiliation of these strains was cross-compared against microbiome components, finding that some of them had close or identical affiliation to the abundant types found in healthy cycles. Strains belonging to the groups already identified as predominant by culture-independent means were screened as potential probiotics based on desirable activities such as antagonism and antibiosis against marine pathogenic bacteria, quorum quenching, bile acid resistance, antibiotic sensitivity and enzymatic activities for improved nutrient digestion. We have also found that in the tracking of microbiome composition across different developmental stages of cobia, healthy cycles exhibited a consistent high relative abundance of a Mesobacillus sp., while in the diseased cycle the emergence of a Vibrio sp. was observed. Our study suggests that epithelocystis in cobia is associated with a displacement of a symbiotic microbiome community linked to the increase frequency of Vibrio species.

19.
Breast Cancer Res ; 13(1): R18, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21299862

RESUMO

INTRODUCTION: Current hormonal adjuvant therapies for breast cancer including tamoxifen treatment and estrogen depletion are overall tumoristatic and are severely limited by the frequent recurrence of the tumors. Regardless of the resistance mechanism, development and progression of the resistant tumors requires the persistence of a basal level of cycling cells during the treatment for which the underlying causes are unclear. METHODS: In estrogen-sensitive breast cancer cells the effects of hormone depletion and treatment with estrogen, tamoxifen, all-trans retinoic acid (ATRA), fulvestrant, estrogen receptor α (ER) siRNA or retinoic acid receptor α (RARα) siRNA were studied by examining cell growth and cycling, apoptosis, various mRNA and protein expression levels, mRNA profiles and known chromatin associations of RAR. RARα subtype expression was also examined in breast cancer cell lines and tumors by competitive PCR. RESULTS: Basal proliferation persisted in estrogen-sensitive breast cancer cells grown in hormone depleted conditioned media without or with 4-hydroxytamoxifen (OH-Tam). Downregulating ER using either siRNA or fulvestrant inhibited basal proliferation by promoting cell cycle arrest, without enrichment for ErbB2/3+ overexpressing cells. The basal expression of RARα1, the only RARα isoform that was expressed in breast cancer cell lines and in most breast tumors, was supported by apo-ER but was unaffected by OH-Tam; RAR-ß and -γ were not regulated by apo-ER. Depleting basal RARα1 reproduced the antiproliferative effect of depleting ER whereas its restoration in the ER depleted cells partially rescued the basal cycling. The overlapping tamoxifen-insensitive gene regulation by apo-ER and apo-RARα1 comprised activation of mainly genes promoting cell cycle and mitosis and suppression of genes involved in growth inhibition; these target genes were generally insensitive to ATRA but were enriched in RAR binding sites in associated chromatin regions. CONCLUSIONS: In hormone-sensitive breast cancer, ER can support a basal fraction of S-phase cells (i) without obvious association with ErbB2/3 expression, (ii) by mechanisms unaffected by hormone depletion or OH-Tam and (iii) through maintenance of the basal expression of apo-RARα1 to regulate a set of ATRA-insensitive genes. Since isoform 1 of RARα is genetically redundant, its targeted inactivation or downregulation should be further investigated as a potential means of enhancing hormonal adjuvant therapy.


Assuntos
Apoproteínas/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Ciclo Celular , Receptores de Estrogênio/metabolismo , Receptores do Ácido Retinoico/metabolismo , Tamoxifeno/uso terapêutico , Sítios de Ligação/genética , Neoplasias da Mama/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/genética , Cromatina/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Isoformas de Proteínas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Receptor alfa de Ácido Retinoico , Tamoxifeno/farmacologia
20.
Plast Reconstr Surg Glob Open ; 9(9): e3796, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34667709

RESUMO

Biopolymers consist of non-biocompatible allogeneic materials. They have been associated with autoimmune inflammatory syndrome induced by adjuvants, as described by Yehuda Shoenfeld and Nancy Agmon-Levin. Therefore, this study aimed to evaluate the clinical and immunological characteristics of patients with autoimmune inflammatory syndrome induced by adjuvants treated at a plastic surgery clinic in Colombia. METHODS: This cross-sectional, descriptive observational study included 190 patients with biopolymers in the buttocks with no evidence of autoimmune disease who were diagnosed with autoimmune inflammatory syndrome induced by adjuvants and underwent treatment at a private plastic surgery clinic from 2017 to 2020. The clinical and paraclinical parameters were measured preoperatively, when the diagnosis of autoimmune inflammatory syndrome induced by adjuvants and the need for material removal were established, and postoperatively after 3 months. RESULTS: The most frequent symptoms were myalgia (92%), arthralgia (77.9%), asthenia (77.9%), adynamia (77.9%), and neurological symptoms (55.8%). Preoperatively, patients were positive for antinuclear antibody, lactate dehydrogenase, complement proteins C3 and C4, and lupus anticoagulant. However, after removal of the biopolymer, there was a decrease in positivity or conversion to a negative status of paraclinical tests. Moreover, there was an association between LDH positivity and disease severity (odds ratio: 4.1, 95% confidence interval: 1.94-8.92). CONCLUSIONS: The removal of biopolymers using an open surgical technique in symptomatic or asymptomatic patients is crucial for functional and reconstructive purposes and to improve the quality of life. Therefore, this condition should be known as "human adjuvant disease caused by biopolymers." Further, this condition mimics autoimmune diseases, with clinical and paraclinical manifestations that improve biopolymer removal.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA