Search results for " Immunology"
showing 10 items of 1841 documents
Fishing pressure impacts the abundance gradient of European lobsters across the borders of a newly established marine protected area
2019
Marine protected areas (MPAs) are considered viable fisheries management tools due to their potential benefits of adult spillover and recruitment subsidy to nearby fisheries. However, before–after control–impact studies that explore the biological and fishery effects of MPAs to surrounding fisheries are scarce. We present results from a fine-scale spatial gradient study conducted before and after the implementation of a 5 km 2 lobster MPA in southern Norway. A significant nonlinear response in lobster abundance, estimated as catch-per-unit-effort (CPUE) from experimental fishing, was detected within 2 years of protection. After 4 years, CPUE values inside the MPA had increased by a magnitu…
De novo biosynthesis of simple aromatic compounds by an arthropod ( Archegozetes longisetosus )
2020
The ability to synthesize simple aromatic compounds is well known from bacteria, fungi and plants, which all share an exclusive biosynthetic route—the shikimic acid pathway. Some of these organisms further evolved the polyketide pathway to form core benzenoids via a head-to-tail condensation of polyketide precursors. Arthropods supposedly lack the ability to synthesize aromatics and instead rely on aromatic amino acids acquired from food, or from symbiotic microorganisms. The few studies purportedly showing de novo biosynthesis via the polyketide synthase (PKS) pathway failed to exclude endosymbiotic bacteria, so their results are inconclusive. We investigated the biosynthesis of aromatic …
Plant guttation provides nutrient-rich food for insects
2020
Plant guttation is a fluid from xylem and phloem sap secreted at the margins of leaves from many plant species. All previous studies have considered guttation as a water source for insects. Here, we hypothesized that plant guttation serves as a reliable and nutrient-rich food source for insects with effects on their communities. Using highbush blueberries as a study system, we demonstrate that guttation droplets contain carbohydrates and proteins. Insects from three feeding lifestyles, a herbivore, a parasitic wasp and a predator, increased their longevity and fecundity when fed on these guttation droplets compared to those fed on control water. Our results also show that guttation droplets…
Critical appraisal of tubular putative eumetazoans from the Ediacaran Weng'an Doushantuo biota
2015
Molecular clock analyses estimate that crown-group animals began diversifying hundreds of millions of years before the start of the Cambrian period. However, the fossil record has not yielded unequivocal evidence for animals during this interval. Some of the most promising candidates for Precambrian animals occur in the Weng'an biota of South China, including a suite of tubular fossils assigned to Sinocyclocyclicus, Ramitubus, Crassitubus and Quadratitubus, that have been interpreted as soft-bodied eumetazoans comparable to tabulate corals. Here, we present new insights into the anatomy, original composition and phylogenetic affinities of these taxa based on data from synchrotron radiation …
Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before - after control-impact study
2013
Published version of an article from the journal: Proceedings of the Royal Society B-Biological Sciences. Alsop available from the Royal Society: http://dx.doi.org/10.1098/rspb.2012.2679 Open Access Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before-after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and parti…
The usefulness of a mathematical model of exposure for environmental risk assessment
2011
We respond to the Comment of Lang et al . [[1][1]] regarding our mathematical model [[2][2]] of exposure of non-target Lepidoptera to Bt -maize pollen expressing Cry1Ab within Europe. Lang et al . remark on the degree to which the model was subject to uncertainty. Perry et al . [[2][2]] did indeed
A mathematical model of exposure of nontarget Lepidoptera to Bt-maize pollen expressing Cry1Ab within Europe
2010
Genetically modified (GM) maize MON810 expresses a Cry1Ab insecticidal protein, derived from Bacillus thuringiensis ( Bt ), toxic to lepidopteran target pests such as Ostrinia nubilalis . An environmental risk to non-target Lepidoptera from this GM crop is exposure to harmful amounts of Bt -containing pollen deposited on host plants in or near MON810 fields. An 11-parameter mathematical model analysed exposure of larvae of three non-target species: the butterflies Inachis io (L.), Vanessa atalanta (L.) and moth Plutella xylostella (L.), in 11 representative maize cultivation regions in four European countries. A mortality–dose relationship was integrated with a dose–distance relationship t…
Anthropoid versus strepsirhine status of the African Eocene primates Algeripithecus and Azibius: craniodental evidence.
2009
Recent fossil discoveries have demonstrated that Africa and Asia were epicentres for the origin and/or early diversification of the major living primate lineages, including both anthropoids (monkeys, apes and humans) and crown strepsirhine primates (lemurs, lorises and galagos). Competing hypotheses favouring either an African or Asian origin for anthropoids rank among the most hotly contested issues in paleoprimatology. The Afrocentric model for anthropoid origins rests heavily on the >45 Myr old fossil Algeripithecus minutus from Algeria, which is widely acknowledged to be one of the oldest known anthropoids. However, the phylogenetic position of Algeripithecus with respect to other p…
Gamma interferon blocks gammaherpesvirus reactivation from latency in a cell type-specific manner
2007
Gammaherpesviruses are important pathogens whose lifelong survival in the host depends critically on their capacity to establish and reactivate from latency, processes regulated by both viral genes and the host immune response. Previous work has demonstrated that gamma interferon (IFN-gamma) is a key regulator of chronic infection with murine gammaherpesvirus 68 (gammaHV68), a virus that establishes latent infection in B lymphocytes, macrophages, and dendritic cells. In mice deficient in IFN-gamma or the IFN-gamma receptor, gammaHV68 gene expression is altered during chronic infection, and peritoneal cells explanted from these mice reactivate more efficiently ex vivo than cells derived from…
Cellular mechanisms of IL-17-induced blood-brain barrier disruption.
2009
Recently T-helper 17 (Th17) cells were demonstrated to disrupt the blood-brain barrier (BBB) by the action of IL-17A. The aim of the present study was to examine the mechanisms that underlie IL-17A-induced BBB breakdown. Barrier integrity was analyzed in the murine brain endothelial cell line bEnd.3 by measuring the electrical resistance values using electrical call impedance sensing technology. Furthermore, in-cell Western blots, fluorescence imaging, and monocyte adhesion and transendothelial migration assays were performed. Experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6 mice. IL-17A induced NADPH oxidase- or xanthine oxidase-dependent reactive oxygen species (ROS)…