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71.
Three anthracene derivatives, auxenone, oncocalyxonol and auxemim, were isolated from Auxemma ontocalyx. The structures of these compounds as 1,4,8-trihydroxy-2-methoxy-5-methyl-9,10-anthraquinone, rel-9alpha,11alpha-epoxy-1,4,8alpha,11alpha-tetrahydroxy-2-methoxy-8a beta-methyl-5,6,7,8,8a,9, 10,10a beta-octahydro-10-anthracenone and rel-8alpha,11beta-epoxy-2,11-dimethoxy-8a beta-methyl-5,6,7,8,8a,9-hexahydro-1,4-anthracenedione were determined by analysis of spectral data (1D and 2D NMR, IR, HREIMS and UV). 相似文献
72.
Joana F. Marques Hong-Lei Wang Glenn P. Svensson Enric Frago Olle Anderbrant 《Evolutionary ecology》2014,28(5):829-848
The brown tail moth (BTM) Euproctis chrysorrhoea (Linnaeus 1758) (Lepidoptera: Erebidae) is a forest and ornamental pest in Europe and the United States. Its extreme polyphagy, and documented phenological shift associated with host use suggest the presence of distinct host-races. To test this hypothesis, we sampled BTM infesting different host species in several locations along its distribution, and used DNA sequence data (a total of 1,672 bp from cytochrome c oxidase subunit I, elongation factor 1-alpha, and wingless) to produce haplotype networks and reconstruct the phylogenetic relationships between individuals. Population genetic diversity indices pointed out a higher genetic diversity in Europe, particularly in the samples from southern Spain and southern England. Lower F ST values were found between geographically closer populations when compared to more distant ones, but analyses of molecular variance and Mantel tests failed to reveal geographically associated genetic differentiation. However, haplotype networks and phylogenetic reconstructions revealed a previously unknown genetic differentiation within the BTM, with one lineage circumscribed to southern Europe. Although BTM haplotypes did not cluster according to their host plant, host-associated haplotypes were observed within certain geographic regions. Hence, our data support the existence of host-races of BTM within southern Spain and southern England, where populations from different hosts occur in sympatry. 相似文献
73.
A. T. Souza E. Dias J. Campos J. C. Marques I. Martins 《Environmental Biology of Fishes》2014,97(6):701-715
The common goby, Pomatoschistus microps, is a relevant species from estuarine food webs, playing important roles as predator of polychaetes and crustaceans and as prey for larger fishes and crustaceans. The Minho estuary (NW Portugal) is a relatively well-preserved and productive system. To assess the population structure and production of P. microps in this estuary, monthly samples were undertaken in three different areas along an estuarine gradient in the lower estuary. The density of P. microps varied considerably among seasons and sampling stations, with higher densities occurring in summer and autumn. The lowest densities were found closer to the sea. In general, the density of females was higher than the density of males in all sampling stations, while juveniles were more abundant within a salt marsh area. Compared with other European estuaries, our data showed a remarkable higher density and production values of P. microps. This may be related to the high freshwater input and the low salinities found in this estuary. In addition, we hypothesize that the lower density of the sympatric species P. minutus and the high availability of bivalve shells observed in the Minho estuary may have also contributed to the present results, once P. minutus and P. microps often display a diet overlap and the bivalve shells are crucial for the common goby reproduction. 相似文献
74.
Six additional characters are proposed to distinguish the nymphs of the perlid genera from Southeastern Brazil, and a practical key is provided. 相似文献
75.
João Torres Joana Marques Paulo Alves Hermenegildo Costa João Honrado 《Ecological Research》2017,32(1):37-49
Local ecosystem resilience to fire disturbance can be influenced by multiple factors, from topography and climate, to fire history and pre-fire structure of biotic communities. Here we investigated the factors affecting post-fire recovery of scrub vegetation in areas under Mediterranean climate affected by frequent fires. We hypothesized that, under comparable climatic and topographic conditions, geological factors (with bedrock type as a proxy) would be at least as important as fire history in explaining patterns of post-fire recovery. We surveyed scrub vegetation in a mountain study area in Portugal, using a stratified random sampling scheme, with fire frequency, time since last fire, and bedrock type (granite vs. schist) as stratifying layers. Based on vegetation and plant community data from 40 plots, we analyzed total species richness and composition, and the relative abundance of functional groups defined on the basis of general (non fire-specific) life-history traits. We found that, at a local scale, lithology can override fire history in determining post-fire recovery. Vegetation plots on granite exhibited a considerable development of tall scrubs and higher values of total species richness. They also hosted higher numbers of animal-dispersed woody species, of trees and tall scrubs, of woody deciduous species, and of forest, edge and tall scrub species. Differences in the post-fire development of scrub vegetation and in the functional profile of plant communities highlight the need to consider local geological diversity when establishing priorities for post-fire active restoration under scenarios of limited resources. 相似文献
76.
The only known monocotylid genus to parasitise Neotropical freshwater stingrays (Potamotrygonidae) is Potamotrygonocotyle Mayes, Brooks & Thorson, 1981, a monotypic genus erected to accommodate P. tsalickisi Mayes, Brooks & Thorson, 1981. For more than 20 years, no other species has been recognised in this genus, but new efforts to survey the diversity of parasites inhabiting potamotrygonids have revealed the existence of new species and the need to redefine the genus. Here, the generic diagnosis of Potamotrygonocotyle is amended, P. tsalickisi is redescribed and four new species are recognised and described based on samples collected from the gills of freshwater potamotrygonids from the La Plata river basin: Potamotrygonocotyle chisholmae n. sp. and P. dromedarius n. sp. from Potamotrygon motoro; Potamotrygonocotyle eurypotamoxenus n. sp. from Potamotrygon cf. motoro (type-host), P. castexi, P. falkneri and P. histrix; and Potamotrygonocotyle uruguayensis n. sp. from Potamotrygon brachyura. Potamotrygonocotyle is characterised by species possessing: (1) slightly sinuous sclerotised ridges on all septa; (2) two pairs of the dorsal haptoral accessory structures associated with the four posterior peripheral loculi and with anterior dorsal haptoral accessory structure bilobate or semicircular; and (3) male copulatory organ without an accessory piece. 相似文献
77.
A. R. Marques G. W. Fernandes I. A. Reis R. M. Assunç;ão 《Plant biology (Stuttgart, Germany)》2002,4(1):94-103
Abstract: This study focuses on the sex ratio and spatial distribution of males and females in three populations of the endemic and restricted tropical dioecious shrub, Baccharis concinna (Asteraceae) in the mountainous region of Serra do Cipó, southeastern Brazil. The proportion of female plants in the population at lower elevation (1000 m a.s.l.) was significantly greater than of male plants. At this elevation of P/N and Ca/Al ratios in the soil were also greater indicating better nutritional status of the soils. The concentration of aluminium increased significantly with the elevation ( p < 0.001), perhaps rendering soils less conducive to female plants at higher elevations. Female plants are possibly adversely affected to a greater extent by soil quality than male plants. The spatial distribution of the populations within habitat was tested by the K(t) function, where the neighbourhood of a given individual was defined by a circle with a radius (t) up to 3 m. Despite the strong tendency for aggregation, the distribution of the sexes within habitats was random and the hypothesis was not supported. The independent distribution of the sexes within habitats may be explained by nutrient homogeneity of the soils, as well as by an absence of antagonism between the sexes. Nevertheless, we found a trend for males and females to be aggregated according to their gender. 相似文献
78.
Peraçoli MT Kurokawa CS Calvi SA Mendes RP Pereira PC Marques SA Soares AM 《Microbes and infection / Institut Pasteur》2003,5(5):413-418
Monocytes and macrophages can produce a large repertoire of cytokines and participate in the pathogenesis of granulomatous diseases. We investigated the production of pro- and anti-inflammatory cytokines by monocytes from patients with active paracoccidioidomycosis. Peripheral blood monocytes from 37 patients and 29 healthy controls were cultivated with or without 10 microg/ml of lipopolysaccharide (LPS) for 18 h at 37 degrees C, and the cytokine levels were determined in the culture supernatants by enzyme immunoassay. The results showed that the endogenous levels of tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-8, IL-10 and transforming growth factor beta detected in the supernatant of patient monocytes cultivated without stimulus were significantly higher than those produced by healthy controls. These data demonstrated that monocytes from patients with active paracoccidioidomycosis produce high levels of cytokines with both inflammatory and anti-inflammatory activities. However, patient monocytes produced significantly lower TNF-alpha and IL-6 levels in response to LPS when compared to normal subjects, suggesting an impairment in their capacity to produce these cytokines after LPS stimulation. Concentrations of IL-1beta, IL-8 and IL-10 in cultures stimulated with LPS were higher in patients than in controls. These results suggest that an imbalance in the production of pro- and anti-inflammatory cytokines might be associated with the pathogenesis of paracoccidioidomycosis. 相似文献
79.
Kubrusly RC Ventura AL de Melo Reis RA Serra GC Yamasaki EN Gardino PF de Mello MC de Mello FG 《Neurochemistry international》2007,50(1):211-218
Dopamine is the main catecholamine found in the chick retina whereas norepinephrine is only found in trace amounts. We compared the effectiveness of dopamine and norepinephrine in promoting cyclic AMP accumulation in retinas at embryonic day 13 (E13) and from post-hatched chicken (P15). Dopamine (EC(50)=10microM) and norepinephrine (EC(50)=30microM), but not the beta(1)-adrenergic agonist isoproterenol, stimulated over seven-fold the production of cyclic AMP in E13 retina. The cyclic AMP accumulation induced by both catecholamines in embryonic tissue was entirely blocked by 2microM SCH23390, a D(1) receptor antagonist, but not by alprenolol (beta-adrenoceptor antagonist). In P15 retinas, 100microM isoproterenol stimulated five-fold the accumulation of cAMP. This effect was blocked by propanolol (10microM), but not by 2microM SCH23390. Embryonic and adult retina display beta(1) adrenergic receptor mRNA as detected by RT-PCR, but the beta(1) adrenergic receptor protein was detected only in post-hatched tissue. We conclude that norepinephrine cross-reacts with D(1) dopaminergic receptor with affinity similar to that of dopamine in the embryonic retina. In the mature retina, however, D(1) receptors become restricted to activation by dopamine. Moreover, as opposed to the embryonic tissue, norepinephrine seems to stimulate cAMP accumulation via beta(1)-like adrenergic receptors in the mature tissue. 相似文献
80.
Daniel Ruivo Marques Paula Castilho Ana Allen Gomes Anabela Pereira 《Chronobiology international》2019,36(4):541-547
It is well established in the literature that morning-type individuals present better health indicators than evening-types. Mindfulness is considered an adaptive self-regulation skill associated with well-being and physical and mental health. However, there is scarce studies that relate chronotype and mindfulness. Thus, in this research, our aim was to study the relationship between chronotype and mindfulness-related variables. For this purpose, a sample composed of 483 participants from the community was recruited through an online survey and invited to fill out the Five Facet Mindfulness Questionnaire, the Self-Compassion Scale, and the Composite Morningness Scale. Regarding mindfulness measure, the results indicated that morning-types presented higher levels of “acting with awareness” than intermediate and evening-types. Additionally, as to self-compassion measure, morning-types presented higher levels of “mindfulness” and “overall self-compassion” than intermediate and evening-types. The remaining associations examined were not statistically significant. In sum, the morning-types showed higher scores in some of the mindfulness and self-compassion scales which seem to suggest that this morningness tendency may function as protective factor concerning eventual disorders´ development. Nonetheless, more systematic studies are needed to better understand this association and subsequently foster changes for psychological intervention. 相似文献