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1.
Sci Rep ; 6: 19215, 2016 Jan 14.
Article in English | MEDLINE | ID: mdl-26765261

ABSTRACT

Caddisflies (Trichoptera) are small, cosmopolitan insects closely related to the Lepidoptera (moths and butterflies). Most caddisflies construct protective cases during their larval development. Although the earliest recognisable caddisflies date back to the early Mesozoic (Early and Middle Triassic), being particularly numerous and diverse during the Late Jurassic and Early Cretaceous, the first records of their larval case constructions are known exclusively from much younger, Early to Middle Jurassic non-marine deposits in the northern hemisphere. Here we present fossils from the Early Permian (Asselian-Sakmarian) marine deposits of Brazil which have strong morphological and compositional similarity to larval cases of caddisflies. If they are, which is very probable, these finds not only push back the fossil record of true caddisflies, but also indicate that their larvae constructed cases at the very beginning of their evolution in marine environments. Since modern caddisflies that construct larval cases in marine environments are only known from eastern Australia and New Zealand, we suggest that this marine ecology may have first evolved in western Gondwana during the Early Permian and later spread across southern Pangea.


Subject(s)
Environment , Fossils , Insecta , Paleontology , Animals , Brazil , Geography , Larva
2.
An. acad. bras. ciênc ; 83(3): 763-774, Sept. 2011. ilus
Article in English | LILACS | ID: lil-595535

ABSTRACT

In this paper we show the existence of new families of convex and concave spatial central configurations for the 5-body problem. The bodies studied here are arranged as follows: three bodies are at the vertices of an equilateral triangle T, and the other two bodies are on the line passing through the barycenter of T that is perpendicular to the plane that contains T.


Neste artigo estudamos a existência de novas famílias de configurações centrais espaciais dos tipos côncavas ou convexas para o problema de 5 corpos. Os corpos estudados aqui estão dispostos da seguinte maneira: três corpos estão sobre os vértices de um triângulo equilátero T e os outros dois corpos estão sobre a reta que passa pelo baricentro de T e é perpendicular ao plano que contém T.

3.
J Ethnopharmacol ; 95(1): 1-5, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15374599

ABSTRACT

One of the best-known multi-purpose medicinal plants in Southern Africa, Sutherlandia frutescens subsp. microphylla (family: Fabaceae/Leguminosa), is used for a wide range of conditions, including cancer, viral diseases and inflammatory conditions. Little scientific data has been documented on the mechanism by which Sutherlandia frutescens acts on the immune system. Phagocyte derived reactive oxygen species, such as hydrogen peroxide and superoxide radicals, are responsible for the pathogenesis of various inflammatory conditions. Anti-inflammatory properties of various medicinal-plant extracts have been explained, at least in part, by their antioxidant activities. We investigated the effects of a hot water extract of Sutherlandia frutescens on both luminol and lucigenin enhanced chemiluminescence of neutrophils stimulated with L-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) as well as its superoxide and hydrogen peroxide scavenging properties in a cell free system. The results indicate that Sutherlandia frutescens extract possesses superoxide as well as hydrogen peroxide scavenging activities at concentrations as low as 10 microg/ml, which could account for some of the anti-inflammatory properties that have been described.


Subject(s)
Antioxidants/pharmacology , Fabaceae , Antioxidants/isolation & purification , Dose-Response Relationship, Drug , Humans , Neutrophils/drug effects , Neutrophils/metabolism , Plant Extracts/isolation & purification , Plant Extracts/pharmacology
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