RESUMO
Ameloblastic fibro-odontoma (AFO) is a mixed odontogenic tumor, which has an epithelial and mesenchymal component. It can be observed in imaging tests as a radiomixed lesion, with some authors claiming it represents only the predecessor of an odontoma. Epidemiologically, it appears between the second and third decade of life, predominantly in males and with a predilection for the posterior area of the mandible. This lesion presents a good prognosis and it responds well to enucleation by curettage with a low rate of recurrence. In the present article, two cases of ameloblastic fibro-odontoma in an unusual region of the maxilla are presented.
El Fibro-odontoma ameloblástico (FOA), es una lesión tumoral mixta de origen odontogénico, el cual tiene un componente epitelial y mesenquimático. En su imagenología se observa como una lesión radiomixta, debido a que algunos autores afirman que este no es más que el predecesor de un odontoma. Epidemiológicamente, se presenta entre la segunda y tercera década de la vida, preferencia por sexo masculino y predilección por el área posterior de la mandíbula. Es una lesión de buen pronóstico que responde bien a la enucleación por curetaje con baja tasa de recidiva. En el presente artículo, se presentan dos casos de fibro-odontoma ameloblástico en una región inusual de los maxilares.
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Anormalidades Dentárias/complicações , Neoplasias Maxilares/complicações , Odontoma/complicações , Radiografia Panorâmica , Mandíbula/diagnóstico por imagemRESUMO
Digitalis purpurea L. is one of the main economically viable sources of cardenolides (cardiac glycosides) for the pharmaceutical industry. Nevertheless, production of cardenolides in plants grown by traditional agriculture is not always an efficient process and can be affected by biotic and abiotic factors. This chapter provides two biotechnology strategies for biomass and cardenolide production in D. purpurea. Firstly, we report biomass production using a temporary immersion system (TIS), combined with cardenolide extraction and quantification. Secondly, an efficient protocol for genetic transformation via Agrobacterium tumefaciens is provided. These strategies can be used independently or combined in order to increase the content of cardiac glycosides in D. purpurea and to unravel biosynthetic pathways associated to cardiac glycoside production.
Assuntos
Biotecnologia/métodos , Cardenolídeos/metabolismo , Digitalis/metabolismo , Agrobacterium tumefaciens/genética , Biomassa , Vias Biossintéticas , Biotecnologia/instrumentação , Cardenolídeos/análise , Cardenolídeos/isolamento & purificação , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Digitalis/química , Digitalis/genética , Digitalis/microbiologia , Desenho de Equipamento , Transformação GenéticaRESUMO
Cymbopogon citratus (D.C.) Stapf. is a medicinal plant source of lemon grass oils with multiple uses in the pharmaceutical and food industry. Conventional propagation in semisolid culture medium has become a fast tool for mass propagation of lemon grass, but the production cost must be lower. A solution could be the application of in vitro propagation methods based on liquid culture advantages and automation. This chapter provides two efficient protocols for in vitro propagation via organogenesis and somatic embryogenesis of this medicinal plant. Firstly, we report the production of shoots using a temporary immersion system (TIS). Secondly, a protocol for somatic embryogenesis using semisolid culture for callus formation and multiplication, and liquid culture in a rotatory shaker and conventional bioreactors for the maintenance of embryogenic culture, is described. Well-developed plants can be achieved from both protocols. Here we provide a fast and efficient technology for mass propagation of this medicinal plant taking the advantage of liquid culture and automation.
Assuntos
Cymbopogon/crescimento & desenvolvimento , Técnicas de Embriogênese Somática de Plantas/métodos , Aclimatação , Reatores Biológicos , Cymbopogon/embriologia , Cymbopogon/fisiologia , Germinação , Organogênese Vegetal , Brotos de Planta/embriologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Plantas Medicinais/embriologia , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/fisiologia , Esterilização/métodosRESUMO
Brown rust caused by the fungus Puccinia melanocephala is a major disease of sugarcane (Saccharum spp.). A sugarcane mutant, obtained by chemical mutagenesis of the susceptible variety B4362, showed a post-haustorial hypersensitive response (HR)-mediated resistance to the pathogen and was used to identify genes differentially expressed in response to P. melanocephala via suppression subtractive hybridization (SSH). Tester cDNA was derived from the brown rust-resistant mutant after inoculation with P. melanocephala, while driver cDNAs were obtained from the non-inoculated resistant mutant and the inoculated susceptible donor variety B4362. Database comparisons of the sequences of the SSH recombinant clones revealed that, of a subset of 89 non-redundant sequences, 88% had similarity to known functional genes, while 12% were of unknown function. Thirteen genes were selected for transcript profiling in the resistant mutant and the susceptible donor variety. Genes involved in glycolysis and C4 carbon fixation were up-regulated in both interactions probably due to disturbance of sugarcane carbon metabolism by the pathogen. Genes related with the nascent polypeptide associated complex, post-translational proteome modulation and autophagy were transcribed at higher levels in the compatible interaction. Up-regulation of a putative L-isoaspartyl O-methyltransferase S-adenosylmethionine gene in the compatible interaction may point to fungal manipulation of the cytoplasmatic methionine cycle. Genes coding for a putative no apical meristem protein, S-adenosylmethionine decarboxylase, non-specific lipid transfer protein, and GDP-L-galactose phosphorylase involved in ascorbic acid biosynthesis were up-regulated in the incompatible interaction at the onset of haustorium formation, and may contribute to the HR-mediated defense response in the rust-resistant mutant.
Assuntos
Basidiomycota/patogenicidade , Resistência à Doença/genética , Doenças das Plantas/genética , Saccharum/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , Saccharum/microbiologia , TranscriptomaRESUMO
Mycosphaerella fijiensis, a hemibiotrophic fungus, is the causal agent of black leaf streak disease, the most serious foliar disease of bananas and plantains. To analyze the compatible interaction of M. fijiensis with Musa spp., a suppression subtractive hybridization (SSH) cDNA library was constructed to identify transcripts induced at late stages of infection in the host and the pathogen. In addition, a full-length cDNA library was created from the same mRNA starting material as the SSH library. The SSH procedure was effective in identifying specific genes predicted to be involved in plant-fungal interactions and new information was obtained mainly about genes and pathways activated in the plant. Several plant genes predicted to be involved in the synthesis of phenylpropanoids and detoxification compounds were identified, as well as pathogenesis-related proteins that could be involved in the plant response against M. fijiensis infection. At late stages of infection, jasmonic acid and ethylene signaling transduction pathways appear to be active, which corresponds with the necrotrophic life style of M. fijiensis. Quantitative PCR experiments revealed that antifungal genes encoding PR proteins and GDSL-like lipase are only transiently induced 30 days post inoculation (dpi), indicating that the fungus is probably actively repressing plant defense. The only fungal gene found was induced 37 dpi and encodes UDP-glucose pyrophosphorylase, an enzyme involved in the biosynthesis of trehalose. Trehalose biosynthesis was probably induced in response to prior activation of plant antifungal genes and may act as an osmoprotectant against membrane damage.
Assuntos
Ascomicetos/genética , Genes de Plantas/genética , Interações Hospedeiro-Patógeno/genética , Musa/genética , Doenças das Plantas/genética , UTP-Glucose-1-Fosfato Uridililtransferase/genética , Ascomicetos/patogenicidade , Ciclopentanos/metabolismo , Etilenos/metabolismo , Etiquetas de Sequências Expressas , Proteínas Fúngicas/genética , Biblioteca Gênica , Musa/microbiologia , Hibridização de Ácido Nucleico , Oxilipinas/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Proteínas de Plantas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Transdução de Sinais , Fatores de TempoRESUMO
Efficient RNA isolation is a prerequisite for gene expression studies and it has an increasingly important role in the study of plant-fungal pathogen interactions. However, RNA isolation is difficult in filamentous fungi. These organisms are notorious for their rigid cell walls and the presence of high levels of carbohydrates, excreted from the fungal cells during submerged growth, which interferes with the extraction procedures. Although many commercial kits are already available for RNA isolation, they do not provide, in most cases, enough amount of pure RNA to be used in upstream applications. In the present work, we propose an easy and efficient protocol for isolating total RNA from the filamentous fungus Mycosphaerella fijiensis, the most important foliar pathogen of Musa spp. varieties worldwide. In addition, we applied the proposed protocol to the isolation of total RNA from banana leaves infected with the pathogen. Our methodology was developed based on the SDS method with modifications including a carbohydrate precipitation step. The protocol resulted in high-quality total RNA, from fungal mycelium grown in PDB medium and infected banana leaves, suitable for further molecular studies. The proposed methodology is also applicable to the ascomycete fungus Passalora fulva (syn. Cladosporum fulvum).