Angela J Davies

..Finally, the haemogregarine species listed in the genus Desseria Siddall, 1995 were reassessed. Of the original list of 41 species, 30 were retained and 5 species added, including D. harriottae, so that the genus now contains 35 species...

..Finally, these appeared to be the first observations of Haemogregarina platessae, and possibly H. terraenovae, from the southern hemisphere...

..The presence of intraerythrocytic binary fission in its fish host means that H. bigemina is not a Desseria. Overall it most closely resembles Haemogregarina (sensu stricto) in its development, although the match is not exact...

..It was concluded that the identification of T. mukasai remains a problem, but at least 2 genotypic groups of trypanosomes occur in Okavango Delta fishes, and catfishes in this region appear to contain both types...

..To assist in this procedure and to clarify the internal anatomy of gnathiids, 3D visualisation of stacked, serial histological sections is being undertaken. Biological transmission experiments should follow these processes...

..It is concluded that the parasite is probably related to Haemohormidium spp. and H. scombri, but it also shares features with some Microsporida...

..Given that H(2)O(2) is an important anti-pathogen molecule, and that haemocytes play a crucial role in the elimination of invading organisms, PKC signalling in these cells is likely to be crucial to the molluscan innate defence response...

..stagnalis haemocytes. We propose a model in which integrin engagement mediates association of PKC with FAK/Src complexes to promote focal adhesion assembly during immune recognition by these cells...

..It is suspected that Z. arugamensis transmits the haemogregarine and trypanosomes simultaneously between fishes, a double event unreported previously from the marine environment...

..Taken together, these results demonstrate a role for integrins in L. stagnalis haemocyte adhesion and defence reactions and, for the first time, link integrin engagement to FAK activation in molluscs...

..Disruption of intracellular HSP70 protein expression in B. glabrata haemocytes by S. mansoni ESPs may be a strategy employed by the parasite to manipulate the immune response of the intermediate snail host...

..001). In contrast, the protein kinase A (PKA) inhibitor KT5720 was without effect. Therefore, PI3-K, but not PKA, appears to control phagocytosis by haemocytes in these gastropod molluscs...

..We therefore propose that the establishment of a compatible relationship between a schistosome and its snail host is at least in part due to down-regulation of cell signalling events in haemocytes...

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..To our knowledge, this is the first report that shows a role for these signalling proteins in the generation of NO in invertebrate defence cells...

..mansoni survival within susceptible B. glabrata...

..fragilis is the cosmopolitan haemogregarine, Haemogregarina bigemina. Nomenclatural correction synonymizing the 2 species is recommended...

..It is possible that Trypanosoma clariense Pienaar, 1962, described from Clarias gariepinus in South Africa, is also a junior synonym of T. mukasai...

..abstract:..

..These findings highlight the remarkable nature of brooding in P. formica and expand the paucity of knowledge of embryological development in gnathiids in general...

..These findings suggest a possible role for host insulin and/or trypanosomal insulin-like molecules in regulating parasite growth in vivo...

..Overall, this study has furthered knowledge of ERK signalling in molluscan immunity and has shown that the ERK pathway regulates the phagocytic activity of molluscan haemocytes...