15 research outputs found
MAP Kinase Phosphatase-2 Plays a Critical Role in Response to Infection by Leishmania mexicana
In this study we generated a novel dual specific phosphatase 4 (DUSP4) deletion mouse using a targeted deletion strategy in order to examine the role of MAP kinase phosphatase-2 (MKP-2) in immune responses. Lipopolysaccharide (LPS) induced a rapid, time and concentration-dependent increase in MKP-2 protein expression in bone marrow-derived macrophages from MKP-2+/+ but not from MKP-2−/− mice. LPS-induced JNK and p38 MAP kinase phosphorylation was significantly increased and prolonged in MKP-2−/− macrophages whilst ERK phosphorylation was unaffected. MKP-2 deletion also potentiated LPS-stimulated induction of the inflammatory cytokines, IL-6, IL-12p40, TNF-α, and also COX-2 derived PGE2 production. However surprisingly, in MKP-2−/− macrophages, there was a marked reduction in LPS or IFNγ-induced iNOS and nitric oxide release and enhanced basal expression of arginase-1, suggesting that MKP-2 may have an additional regulatory function significant in pathogen-mediated immunity. Indeed, following infection with the intracellular parasite Leishmania mexicana, MKP-2−/− mice displayed increased lesion size and parasite burden, and a significantly modified Th1/Th2 bias compared with wild-type counterparts. However, there was no intrinsic defect in MKP-2−/− T cell function as measured by anti-CD3 induced IFN-γ production. Rather, MKP-2−/− bone marrow-derived macrophages were found to be inherently more susceptible to infection with Leishmania mexicana, an effect reversed following treatment with the arginase inhibitor nor-NOHA. These findings show for the first time a role for MKP-2 in vivo and demonstrate that MKP-2 may be essential in orchestrating protection against intracellular infection at the level of the macrophage
Colonisation, Gene Frequencies and Enzyme Activity at GPI Locus of Balanus amphitrite (Cirripedia: Thoracica) in the Lagoon of Venice
AFLPs support deep relationships among darters (Percidae: Etheostomatinae) consistent with morphological hypotheses
Recent attention has focused on the efficacy of amplified fragment length polymorphisms (AFLPs) for resolving deep evolutionary relationships. Here we show that AFLPs provide resolution of deep relationships within the family Percidae that are more consistent with previous morphological hypotheses than are relationships proposed by previous molecular analyses. Despite in silico predictions, we were able to resolve relatively ancient divergences, estimated at >25 MA. We show that the most distantly related species share the fewest fragments, but suggest that large data sets and extensive taxon sampling are sufficient to overcome this obstacle of the AFLP technique for deep divergences. We compare genetic distances estimated from mitochondrial DNA with those from AFLPs and contrast traditional PAUP(*) Nei–Li AFLP genetic distances with a recently proposed method utilizing the Dice equation with constraining nucleotides
Environmental DNA assays for the sister taxa sauger (Sander canadensis) and walleye (Sander vitreus)
Social Behaviours and Networks of Vervet Monkeys Are Influenced by Gastrointestinal Parasites
A missense mutation in solute carrier family 12, member 1 (SLC12A1) causes hydrallantois in Japanese Black cattle
Are we paying too much attention to cardio-pulmonary nematodes and neglecting old-fashioned worms like <it>Trichuris vulpis</it>?
<p>Abstract</p> <p><it>Trichuris vulpis</it>, the dog whipworm, causes an intestinal parasitosis of relevance in current canine veterinary practice. Its occurrence is well-known in pets, kennelled dogs and stray animals, and its eggs contaminate the ground in urban areas all over the world. Moreover, <it>T. vulpis </it>has been occasionally incriminated, though not convincingly substantiated, as a cause of zoonosis. This nematode is erroneously considered an "old-fashioned" pathogen with a consequent lack of up- to- date knowledge on several aspects of the infection. These, in turn, are still controversial and need to be studied in greater depth. This article reviews current knowledge of <it>T. vulpis</it>, together with a discussion of critical points in epidemiology, zoonotic hazard, diagnosis and treatment of canine trichurosis.</p