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1.
J Chem Ecol ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270732

RESUMO

To what extent particular plant defences against herbivorous insects are constitutive or inducible will depend on the costs and benefits in their neighbourhood. Some defensive chemicals in leaves are thought to be costly and hard to produce rapidly, while others, including volatile organic compounds that attract natural enemies, might be cheaper and can be released rapidly. When surrounding tree species are more closely related, trees can face an increased abundance of both specialist herbivores and their parasitoids, potentially increasing the benefits of constitutive and inducible defences. To test if oaks (Quercus robur) respond more to herbivore attacks with volatile emission than with changes in leaf phenolic chemistry and carbon to nitrogen ratio (C: N), and whether oaks respond to the neighbouring tree species, we performed an experiment in a forest in Poland. Oak saplings were placed in neighbourhoods dominated by oak, beech, or pine trees, and half of them were treated with the phytohormone methyl jasmonate (elicitor of anti-herbivore responses). Oaks responded to the treatment by emitting a different volatile blend within 24 h, while leaf phenolic chemistry and C: N remained largely unaffected after 16 days and multiple treatments. Leaf phenolics were subtly affected by the neighbouring trees with elevated flavan-3-ols concentrations in pine-dominated plots. Our results suggest that these oaks rely on phenols as a constitutive defence and when attacked emit volatiles to attract natural enemies. Further studies might determine if the small effect of the neighbourhood on leaf phenolics is a response to different levels of shading, or if oaks use volatile cues to assess the composition of their neighbourhood.

2.
Eur J Haematol ; 100(5): 465-474, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29427355

RESUMO

OBJECTIVES: PALG CLL4 is the first, randomized, phase IIIb study with rituximab, cladribine, and cyclophosphamide (RCC) induction and subsequent maintenance with rituximab in previously untreated chronic lymphocytic leukemia (CLL) patients. METHODS: The induction treatment consisted of 6 RCC cycles regimen. Patients with complete response (CR) or partial response (PR) after an induction phase were randomized into a maintenance arm with rituximab or an observational arm. RESULTS: In the intention-to-treat population, 97 patients completed the induction phase with an overall response rate (ORR) of 73.2% (CR 22.7%, PR 50.5%). Subsequently, 66 patients were randomized into the rituximab maintenance arm (n = 33) or the observational arm (n = 33). CR rates were 57.1% in the maintenance group vs 50% in the observational group. PFS was significantly longer in the rituximab maintenance vs the observational arm (P = .028). The multivariate Cox model indicated that del17p (P = .006) and elevated beta-2-microglobulin (P = .015) significantly increased the hazard ratio (HR) of progression, whereas the presence of CD38 (P = .013) significantly decreased it; maintenance therapy with rituximab (P < .0001) significantly decreased the HR of disease progression. CONCLUSIONS: The study confirmed the high efficacy and acceptable safety profile of induction therapy with RCC and maintenance therapy with rituximab in previously untreated patients with CLL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores , Cladribina/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Humanos , Imunofenotipagem , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Quimioterapia de Manutenção , Masculino , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Indução de Remissão , Rituximab/administração & dosagem , Resultado do Tratamento
3.
Zootaxa ; 3779: 394-6, 2014 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-24871734

RESUMO

Ypsolopha lonicerella Stöckl, 1922 is shown to be a junior synonym of Y. leuconotella Snellen, 1884.


Assuntos
Lepidópteros/classificação , Estruturas Animais/anatomia & histologia , Animais , Feminino , Lepidópteros/anatomia & histologia , Masculino
4.
Insects ; 13(4)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35447809

RESUMO

Communities of herbivorous insects on individual host trees may be driven by processes ranging from ongoing development via recent microevolution to ancient phylogeny, but the relative importance of these processes and whether they operate via trophic interactions or herbivore movement remains unknown. We determined the leaf phenology, trunk diameter, genotype, and neighbourhood of sessile oak trees (Quercus petraea), and sampled their caterpillar communities. We found that leaf development across a time period of days related to free-living caterpillars, which disappeared with leaf age. Tree growth across decades is related to increased parasitism rate and diversity of herbivores. The microevolution of oak trees across millennia is related to the abundance of leaf-mining casebearers, which is higher on more homozygous oaks. However, oak genome size was not important for any guild. In contrast to most previous studies, the phylogenetic distance of oaks from their neighbours measured in millions of years was associated with higher abundances of entire caterpillar guilds. Furthermore, on trees surrounded by only distantly related tree species, parasitism tended to be lower. Lower parasitism, in turn, was associated with higher abundances of codominant caterpillar species. Neighbourhoods and traits of trees were also related to community composition and diversity, but not to the average wingspans or specialization of species, consistent with the assembly of herbivore communities being driven by leaf traits and parasitism pressure on trees rather than by insect movement among trees. However, movement in rarer species may be responsible for concentration effects in more phylogenetically distant neighbourhoods. Overall, we suggest that the assembly of insects on a tree is mostly driven by trophic interactions controlled by a mosaic of processes playing out over very different time scales. Comparisons with the literature further suggest that, for oak trees, the consequences of growing amongst distantly related tree species may depend on factors such as geographic region and tree age.

5.
Insects ; 10(7)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277503

RESUMO

Recently in Poland, cases of host expansion have frequently been observed in the typically monophagous bird-cherry ermine moth (Yponomeuta evonymella), which has moved from its native host plant, bird cherry (Prunus padus), to a new, widely distributed plant that is invasive in Europe, black cherry (P. serotina). We attempted to verify the reasons behind this host change in the context of the enemy-free space hypothesis by focusing on parasitoids attacking larval Y. evonymella on one of three host plant variants: The primary host, P. padus; initially P. padus and later P. serotina (P. padus/P. serotina); or the new host, P. serotina. This experiment investigated if changing the host plant could be beneficial to Y. evonymella in terms of escaping from harmful parasitoids and improving survival rate. We identified nine species of parasitoids that attack larval Y. evonymella, and we found that the number of parasitoid species showed a downward trend from the primary host plant to the P. padus/P. serotina combination to the new host plant alone. We observed a significant difference among variants in relation to the percentage of cocoons killed by specific parasitoids, but no effects of non-specific parasitoids or other factors. Total mortality did not significantly differ (ca. 37%) among larval rearing variants. Changing the host plant caused differences in the structure of the parasitoid complex of Y. evonymella but did not improve its survival rate. This study does not indicate that the host expansion of Y. evonymella is associated with the enemy-free space hypothesis; we therefore discuss alternative scenarios that may be more likely.

6.
Zootaxa ; 3956(3): 445-8, 2015 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-26248931

RESUMO

Eidophasia tauricella Staudinger, 1880 is redescribed with a photo of the type specimen. The female genitalia are described for the first time.


Assuntos
Mariposas/classificação , Animais , Feminino , Genitália Feminina/anatomia & histologia , Mariposas/anatomia & histologia , Turquia
7.
Zootaxa ; 3994(4): 585-92, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26250293

RESUMO

A new combination, Rhigognostis erysiphaea (Meyrick, 1938) is proposed. The species is re-described with a photo of the type specimen. The male and female genitalia are described and illustrated for the first time.


Assuntos
Lepidópteros/classificação , Animais , Feminino , Genitália Feminina/anatomia & histologia , Genitália Masculina/anatomia & histologia , Lepidópteros/anatomia & histologia , Masculino
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