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1.
Plant Biol (Stuttg) ; 23(6): 1037-1043, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34516716

RESUMO

Host plant selection by herbivores is driven by a complex array of cues, including leaf traits and previous leaf damage. Herbivore-associated cues to host selection at the plant and leaf scale aid understanding of mechanisms responsible for host preference that might translate into increased performance, as well as processes structuring herbivore populations mediated by interactions. We investigated how changes induced by a galling insect in the tropical fern Cyathea phalerata act as repellent or attractant cues for sawfly feeding and the effects of leaf size on herbivory levels. We recorded gall abundance, damage by chewers, leaf size, plant nutritional quality, phenolic concentration and leaf anatomical traits between galled and non-galled leaf samples. Galled samples contained less N, higher levels of phenolics and higher C/N ratio. However, leaf-chewing damage did not differ between galled and non-galled leaves. The gall structure was avoided by chewers, as it had high concentrations of phenolics, lignification and suberization. Larger leaves sustained higher gall abundance, but leaf size did not have a significant effect on chewer damage. A co-occurrence index calculated for both guilds indicated that galls and chewers exhibited a distribution that did not differ from random, reinforcing that the two guilds on C. phalerata do not show patterns of repulsion such as those maintained by interspecific competition. Sawflies dismissing chemical cues indicate that the increase in phenolics caused by galling insects does not generate increased protection of the galled pinnules. Our results highlight ferns as key resources for herbivores and as a potential plant group to study new research avenues on plant-insect interactions.


Assuntos
Gleiquênias , Animais , Herbivoria , Insetos , Fenótipo , Folhas de Planta
2.
J Food Sci Technol ; 56(6): 3164-3169, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31205372

RESUMO

This study analyzes the lipid composition and the oxidative stability of oils of Sapindaceae and Meliaceae seeds. The oil content ranged from 14.7% (Guarea guidonia) to 30.1% (Allophylus puberulus and Paullinia elegans). Ten fatty acids were identified in seed oils. Guarea guidonia seeds accumulated mainly oleic (44.9%) and linoleic (24.1%) acid, whereas the unusual gondoic and paullinic acids were identified in A. puberulus (15.8%; 8.9%) and P. elegans (14.4%; 44.2%), respectively. The oil of P. elegans had the highest oxidative stability (16.2 h.). Tocopherol predominated in A. puberulus (10.4 mg/100 g) and tocotrienol predominated in G. guidonea and P. elegans (2.6 mg/100 g). The vitamers α-tocopherol, γ-tocopherol, and γ-tocotrienol were found in the studied oils. ß-carotene was predominantly detected in the oil of A. puberulus seeds (22.4 µg/g). Guarea guidonia seed oil has a high potential in food due to richness in essential fatty acids. In turn, A. puberulus and P. elegans oils could be suggested for other industrial purposes (e.g., biodiesel, varnishes, paints, soaps, or oleochemicals) due to their content of long-chain fatty acids.

3.
Genet Mol Res ; 11(1): 556-71, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22535391

RESUMO

Olive trees have been grown since the beginning of civilization, and the consumption of olives and olive products is increasing worldwide, due to their health benefits and organoleptic qualities. To meet the growing market for olives, commercial cultivation of this species is expanding from traditional areas to new regions. Although the Brazilian olive industry has just begun to be established, breeding programs are already developing cultivars that are more adapted to local conditions. We used 12 microsatellite markers to evaluate 60 olive accessions, including several cultivars that were developed in Brazil. The analyses identified 72 distinct alleles; the largest number of alleles per locus were at the markers GAPU 101 and GAPU 71B, which contained 10 and 9 alleles, respectively. The largest allelic diversity and polymorphic information contents were also found at the GAPU 101 and GAPU 71B markers, with values of 0.8399/0.8203 and 0.8117/0.7863, respectively. Additionally, the 12 microsatellite markers generated a cumulative identity probability of 1.51 x 10(-10), indicating a high level of accuracy of accession identification. The set of markers that we used allowed the identification of 52 of the 60 olive genotypes, in addition to the recognition of several varietal synonyms. The components of a two-dimensional principal coordinate analysis explained 48.6% of the total genetic variation. The results obtained from the microsatellite markers showed a substantial degree of genetic diversity in the olive tree accessions used in Brazil.


Assuntos
Variação Genética , Repetições de Microssatélites , Olea/genética , Alelos , Brasil , Análise por Conglomerados , Genótipo , Olea/classificação , Filogenia
4.
Neotrop Entomol ; 40(5): 622-4, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22068952

RESUMO

The mite Oxycenus maxwelli (Keifer) (Eriophyidae) is reported for the first time in Brazil infesting olive trees, Olea europaea. Specimens were found on seedlings at Maria da Fé, state of Minas Gerais, in 2007. Although minor symptoms were not noticed, significant damage to plants were observed. There is no reliable evidence of when the mite could have been introduced. It is believed that the mite occurs since the first introductions of olive trees, around 1820, through vegetative propagating material, but the mite remained unnoticed due to the lack of studies with olive trees in Brazil.


Assuntos
Ácaros , Olea/parasitologia , Animais , Brasil
5.
J Chemother ; 18(5): 473-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17127222

RESUMO

A polymeric micro- and nanosphere formulation using poly (epsilon-caprolactone) (PCL) to entrap an antituberculosis drug, isoniazid (INH), was developed and characterized. The microspheres were prepared by a solvent evaporation method using ethyl acetate, PCL and INH as the organic phase and water and Tween 40 as the aqueous phase. The nanospheres were prepared by a spontaneous emulsification solvent diffusion method using 40% ethanol in acetone (v/v), PCL and INH as the organic phase and water and Tween 40 as the aqueous phase. After freeze-drying, these systems were characterized by scanning electron microscopy (SEM), particle size analysis, determination of entrapped INH content, in vitro INH release and brine shrimp toxicity bioassay.


Assuntos
Caproatos/farmacocinética , Composição de Medicamentos/métodos , Isoniazida/farmacocinética , Lactonas/farmacocinética , Microesferas , Nanotubos , Animais , Antibióticos Antituberculose/farmacocinética , Artemia/efeitos dos fármacos , Caproatos/química , Preparações de Ação Retardada/farmacocinética , Sistemas de Liberação de Medicamentos , Lactonas/química , Nanotubos/química , Tamanho da Partícula , Polímeros/química , Polímeros/farmacocinética , Testes de Toxicidade
6.
Braz J Med Biol Res ; 32(8): 961-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10454757

RESUMO

The short chain fatty acids (SCFA) are the best nutrients for the colonocytes. Glucose is poorly used as a fuel but may be transformed into SCFA by colonic bacteria. The aim of this study was to investigate the effect of SCFA or glucose on experimental colitis. Colitis was induced in 30 Wistar rats by colonic instillation of 4% acetic acid. Five days later they were randomized to receive twice a day colonic lavage containing saline (controls, N = 10), 10% hypertonic glucose (N = 10) or SCFA (N = 10) until day 8 when they were killed. At autopsy, the colon was removed and weighed and the mucosa was evaluated macro- and microscopically and stripped out for DNA assay. Data are reported as mean +/- SD or median [range] as appropriate. All animals lost weight but there was no difference between groups. Colon weight was significantly lower in the SCFA group (3.8 +/- 0.5 g) than in the control (5.3 +/- 2.1 g) and glucose (5.2 +/- 1.3 g) groups (P<0.05). Macroscopically, the severity of inflammation was less in SCFA (grade 2 [1-5]) than in control (grade 9 [4-10]) and glucose-treated (grade 9 [2-10]) animals (P<0.01). Microscopically, ulceration of the mucosa was more severe in the glucose and control groups than in the SCFA group. The DNA content of the mucosa of SCFA-treated animals (8.2 [5.0-20.2] mg/g of tissue) was higher than in glucose-treated (5.1 [4.2-8.5] mg/g of tissue; P<0.01) and control (6.2 [4.5-8.9] mg/g of tissue; P<0.05) animals. We conclude that SCFA may enhance mucosal re-epithelialization in experimental colitis, whereas hypertonic glucose is of no benefit.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Ácidos Graxos Voláteis/uso terapêutico , Mucosa Intestinal/efeitos dos fármacos , Ácido Acético , Animais , Colite Ulcerativa/induzido quimicamente , Epitélio/efeitos dos fármacos , Ácidos Graxos Voláteis/farmacologia , Solução Hipertônica de Glucose/uso terapêutico , Masculino , Ratos , Ratos Wistar , Estatísticas não Paramétricas
8.
G Ital Cardiol ; 13(10): 267-71, 1983 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-6667811

RESUMO

A case of interventricular septal rhabdomyoma in a one day-old newborn is presented. The newborn was moderately cyanosed. A 3/6 systolic murmur in basal area was present. An electrocardiogram showed the features of Wolff-Parkinson-White syndrome. A chest x-ray showed distinct cardiomegaly. M-Mode (MME) and Two-dimensional echocardiography (2DE) identified an interventricular septal mass within left ventricle and suggested the presence of left ventricular outflow obstruction. We emphasize the usefulness of MME and 2DE in accurately diagnosing intramural ventricular tumors in newborns.


Assuntos
Ecocardiografia , Neoplasias Cardíacas/diagnóstico , Septos Cardíacos , Doenças do Recém-Nascido , Rabdomioma/diagnóstico , Humanos , Recém-Nascido , Masculino
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