Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Cladistics ; 38(5): 595-611, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35569142

RESUMO

We examined the impact of successive alignment quality-control steps on downstream phylogenomic analyses. We applied a recently published phylogenomics pipeline that was developed for the Angiosperms353 target-sequence-capture probe set to the flowering plant order Celastrales. Our final dataset consists of 158 species, including at least one exemplar from all 109 currently recognized Celastrales genera. We performed nine quality-control steps and compared the inferred resolution, branch support, and topological congruence of the inferred gene and species trees with those generated after each of the first six steps. We describe and justify each of our quality-control steps, including manual masking, in detail so that they may be readily applied to other lineages. We found that highly supported clades could generally be relied upon even if stringent orthology and alignment quality-control measures had not been applied. But separate instances were identified, for both concatenation and coalescence, wherein a clade was highly supported before manual masking but then subsequently contradicted. These results are generally reassuring for broad-scale analyses that use phylogenomics pipelines, but also indicate that we cannot rely exclusively on these analyses to conclude how challenging phylogenetic problems are best resolved.


Assuntos
Celastrales , Magnoliopsida , Magnoliopsida/genética , Filogenia
2.
Mol Phylogenet Evol ; 59(2): 320-30, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21338700

RESUMO

The phylogeny of Celastraceae subfamily Hippocrateoideae (∼ 100 species and 19 genera in the Old and New World tropics) was inferred using morphological characters together with plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) genes. The subfamily is easily recognized by the synapomorphies of transversely flattened, deeply lobed capsules and seeds with membranous basal wings or narrow stipes together with bisexual, 5-merous flowers that generally have an extrastaminal disk and three stamens. Hippocrateoideae, like Salacioideae, are inferred to have an Old World origin. The narrow stipes of Neotropical species that are water-dispersed are inferred to be derived within the subfamily from ancestral species with wind-dispersed winged seeds. Helictonema, a monotypic genus endemic to tropical Africa, has a small, white, spongy aril that is located at the base of the seed wing and appears to be unique within Hippocrateoideae. Our inference that Helictonema is sister to the remaining members of the subfamily, considered in the context of Sarawakodendron being sister to Salacioideae, suggests that small arils and capsular fruit were primitive within both subfamilies. The aril became dramatically enlarged within Salacioideae, in which the fruits are berries, and lost entirely within Hippocrateoideae, in which the fruits are transversely flattened capsules. All five Old World taxa of Prionostemma and all eight currently recognized species within Simirestis are transferred to Pristimera, one South African variety of Pristimera is raised to species level, and all three taxa in Pristimera subgenus Trochantha are transferred to the new genus Trochantha.


Assuntos
Celastraceae/anatomia & histologia , Celastraceae/genética , Filogenia , Sequência de Bases , Celastraceae/classificação , DNA Ribossômico/genética , Flores/anatomia & histologia , Genomas de Plastídeos/genética , Dados de Sequência Molecular , Sementes/citologia , Análise de Sequência de DNA
3.
Rev. bras. farmacogn ; 20(5): 742-750, Oct.-Nov. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-567430

RESUMO

Ethanol extracts of eighteen Bignoniaceae species have been evaluated by the MTT assay for cytotoxicity in Vero cells and for antiviral activity against Human herpes virus type 1, Vaccinia virus and murine Encephalomyocarditis virus. Among such species, seven are reported to be of traditional medicinal use No cytotoxicity was observed for most of the extracts up to the concentration of 500 μg/mL. Fourteen (50 percent) of the 28 extracts assayed have disclosed antiviral activity with EC50 values in the range of 4.6+0.3 to 377.2+17.7 μg/mL. Only two species, Arrabidaea samydoides and Callichlamys latifolia, have shown activity against all the three viruses. The extracts were chemically characterized by their TLC and HPLC-DAD profiles. Mangiferin is the major constituent of A. samydoides but the isolated compound has been less active than the crude extract. This is the first report on the antiviral evaluation of the eighteen Bignoniaceae species assayed.


Extratos etanólicos de dezoito espécies vegetais pertencentes à família Bignoniaceae, das quais sete são descritas como de uso medicinal, foram avaliados, pelo ensaio colorimétrico do MTT, para atividades citotóxica, em células Vero, e antiviral, frente aos vírus herpes simplex-tipo 1, vaccinia e encefalomiocardite murina. A maior parte dos extratos não apresentou citotoxicidade até a concentração de 500 μg/mL. Dos 28 extratos testados quatorze (50 por cento) apresentaram atividade antiviral com valores de CE50 na faixa de 4,6+03 a 377,2+17,7 μg/mL. Somente duas espécies, Arrabidaea samydoides e Callichlamys latifolia, foram ativas frente aos três vírus. Os extratos foram caracterizados pelos seus perfís cromatográficos em CCD e CLAE-FR. Análises por CLAE-FR mostraram que a mangiferina é o constituinte majoritário em A. samydoides mas a substância isolada foi menos ativa do que o extrato bruto. Esta é a primeira vez que se relata a atividade antiviral de extratos das dezoito espécies avaliadas.

4.
Fitoterapia ; 78(5): 353-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17513067

RESUMO

The potential antihypertensive activity of Brazilian plants was evaluated in vitro by its ability to inhibit the angiotensin-converting enzyme (ACE). Forty-four plants belonging to 30 families were investigated. Plants were selected based on their popular use as antihypertensive and/or diuretics. The following plants presented significant ACE inhibition rates: Calophyllum brasiliense, Combretum fruticosum, Leea rubra, Phoenix roebelinii and Terminalia catappa.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Brasil , Calophyllum , Combretum , Humanos , Medicina Tradicional , Componentes Aéreos da Planta , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta , Caules de Planta , Terminalia
5.
Biol Pharm Bull ; 29(11): 2307-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17077535

RESUMO

Ethanol extract from Arrabidaea triplinervia leaves showed in vitro activity (ED100 5.0 mg/ml) against trypomastigotes of Trypanosoma cruzi, the etiologic agent of Chagas; disease. Bioactivity-directed fractionation of this extract led to the isolation of ursolic and oleanolic acids as trypanocidal compounds besides pomolic acid (not tested) and alpinetine (inactive). A series of natural and synthetic derivatives of ursolic and oleanolic acids was simultaneously assayed for structure activity relationships (SAR) studies. Ursolic acid (ED100 0.4 mg/ml) was four times more active than oleanolic acid (ED100 1.6 mg/ml). The presence of free hydroxy and/or carboxy groups is necessary for the trypanocidal activity as could be deduced from the effect of the acetates, methyl ester, and aldehyde derivatives.


Assuntos
Bignoniaceae/química , Triterpenos/farmacologia , Tripanossomicidas/farmacologia , Animais , Doença de Chagas/sangue , Doença de Chagas/parasitologia , Doença de Chagas/prevenção & controle , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Espectrometria de Massas/métodos , Camundongos , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Testes de Sensibilidade Parasitária/métodos , Fitoterapia/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/crescimento & desenvolvimento , Ácido Ursólico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...