The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform
D L Lee - One of the best experts on this subject based on the ideXlab platform.
-
the serum immune response of young lambs to a primary infection with nematodirus Battus
Parasitology, 1996Co-Authors: M D Winter, C Wright, D Wakelin, D L LeeAbstract:Young lambs (6-8 weeks of age) were infected with 50000 infective stage larvae of the trichostrongyle nematode Nematodirus Battus. Initial mean adult worm burdens of 23884 +/- 1678 (S.E.M.) at day 14 post-infection (p.i.) were reduced significantly (P < 0.01) to a mean burden of 5383 +/- 1397 by day 21 p.i. Blood samples were taken and serum analysed using ELISA and Western blotting techniques for IgG antibodies specific for N. Battus. Pre-infection serum from young naive animals showed IgG recognition of adult and larval N. Battus whole worm homogenate. Recognition of adult antigens became reduced during the first 14 days after infection, followed by a subsequent increase beginning between days 14 and 18 p.i. and peaking at day 28 p.i. IgM recognition of N. Battus antigens showed a single response peak, starting between days 14 and 18 p.i., without the pre-infection elevated titre as observed with IgG. These results show that young lambs can mount a significant serum response to a primary infection with N. Battus during rejection of adult worms and that lambs receive from their dams IgG antibodies that are capable of recognizing adult and larval N. Battus during the first few weeks of life.
-
vasoactive intestinal polypeptide like and peptide histidine isoleucine like proteins excreted secreted by nippostrongylus brasiliensis nematodirus Battus and ascaridia galli
Parasitology, 1996Co-Authors: N Foster, D L LeeAbstract:Vasoactive intestinal polypeptide (VIP)-like protein was detected by dot blot analysis in the excretions/secretions (E/S) of Nematodirus Battus and Ascaridia galli and was confirmed in the E/S of Nippostrongylus brasiliensis. ELISA analysis showed that N. brasiliensis E/S contained the highest proportion of VIP-like protein (28.04 pmoles/mg of total E/S protein) and A. galli E/S contained the lowest (10.89 pmoles/mg of total E/S protein). Peptide histidine isoleucine (PHI)-like protein was detected by dot blot analysis in the E/S products of N. brasiliensis, N. Battus and A. galli. ELISA analysis suggested that A. galli E/S contained the highest proportion of PHI (20.77 nmoles/mg of total E/S protein) and N. Battus E/S contained the lowest (0.67 nmoles/mg of total E/S protein). The possible significance of VIP-like and PHI-like substances in the E/S of gastrointestinal nematodes is discussed.
-
Vasoactive intestinal polypeptide-like and peptide histidine isoleucine-like proteins excreted/secreted by Nippostrongylus brasiliensis, Nematodirus Battus and Ascaridia galli.
Parasitology, 1996Co-Authors: N Foster, D L LeeAbstract:Vasoactive intestinal polypeptide (VIP)-like protein was detected by dot blot analysis in the excretions/secretions (E/S) of Nematodirus Battus and Ascaridia galli and was confirmed in the E/S of Nippostrongylus brasiliensis. ELISA analysis showed that N. brasiliensis E/S contained the highest proportion of VIP-like protein (28.04 pmoles/mg of total E/S protein) and A. galli E/S contained the lowest (10.89 pmoles/mg of total E/S protein). Peptide histidine isoleucine (PHI)-like protein was detected by dot blot analysis in the E/S products of N. brasiliensis, N. Battus and A. galli. ELISA analysis suggested that A. galli E/S contained the highest proportion of PHI (20.77 nmoles/mg of total E/S protein) and N. Battus E/S contained the lowest (0.67 nmoles/mg of total E/S protein). The possible significance of VIP-like and PHI-like substances in the E/S of gastrointestinal nematodes is discussed.
Robin B. Gasser - One of the best experts on this subject based on the ideXlab platform.
-
Differences in the second internal transcribed spacer of four species of Nematodirus (Nematoda: Molineidae)☆
International Journal for Parasitology, 1998Co-Authors: Lisa A. Newton, Neil B Chilton, Ian Beveridge, Robin B. GasserAbstract:Abstract Genetic differences among Nematodirus spathiger, Nematodirus filicollis, Nematodirus helvetianus and Nematodirus Battus in the nucleotide sequence of the second internal transcribed spacer (ITS-2) of ribosomal DNA ranged from 3.9 to 24.7%. Pairwise comparisons of their ITS-2 sequences indicated that the most genetically similar species were N. spathiger and N. helvetianus. N. Battus was the most genetically distinct species, with differences ranging from 22.8 to 24.7% with respect to the other three species. Some of the nucleotide differences among species provided different endonuclease restriction sites that could be used in restriction fragment length polymorphism studies. The ITS-2 sequence data may prove useful in studies of the systematics of molineid nematodes.
-
differences in the second internal transcribed spacer of four species of nematodirus nematoda molineidae
International Journal for Parasitology, 1998Co-Authors: Lisa A. Newton, Neil B Chilton, Ian Beveridge, Robin B. GasserAbstract:Genetic differences among Nematodirus spathiger, Nematodirus filicollis, Nematodirus helvetianus and Nematodirus Battus in the nucleotide sequence of the second internal transcribed spacer (ITS-2) of ribosomal DNA ranged from 3.9 to 24.7%. Pairwise comparisons of their ITS-2 sequences indicated that the most genetically similar species were N. spathiger and N. helvetianus. N. Battus was the most genetically distinct species, with differences ranging from 22.8 to 24.7% with respect to the other three species. Some of the nucleotide differences among species provided different endonuclease restriction sites that could be used in restriction fragment length polymorphism studies. The ITS-2 sequence data may prove useful in studies of the systematics of molineid nematodes.
N Foster - One of the best experts on this subject based on the ideXlab platform.
-
vasoactive intestinal polypeptide like and peptide histidine isoleucine like proteins excreted secreted by nippostrongylus brasiliensis nematodirus Battus and ascaridia galli
Parasitology, 1996Co-Authors: N Foster, D L LeeAbstract:Vasoactive intestinal polypeptide (VIP)-like protein was detected by dot blot analysis in the excretions/secretions (E/S) of Nematodirus Battus and Ascaridia galli and was confirmed in the E/S of Nippostrongylus brasiliensis. ELISA analysis showed that N. brasiliensis E/S contained the highest proportion of VIP-like protein (28.04 pmoles/mg of total E/S protein) and A. galli E/S contained the lowest (10.89 pmoles/mg of total E/S protein). Peptide histidine isoleucine (PHI)-like protein was detected by dot blot analysis in the E/S products of N. brasiliensis, N. Battus and A. galli. ELISA analysis suggested that A. galli E/S contained the highest proportion of PHI (20.77 nmoles/mg of total E/S protein) and N. Battus E/S contained the lowest (0.67 nmoles/mg of total E/S protein). The possible significance of VIP-like and PHI-like substances in the E/S of gastrointestinal nematodes is discussed.
-
Vasoactive intestinal polypeptide-like and peptide histidine isoleucine-like proteins excreted/secreted by Nippostrongylus brasiliensis, Nematodirus Battus and Ascaridia galli.
Parasitology, 1996Co-Authors: N Foster, D L LeeAbstract:Vasoactive intestinal polypeptide (VIP)-like protein was detected by dot blot analysis in the excretions/secretions (E/S) of Nematodirus Battus and Ascaridia galli and was confirmed in the E/S of Nippostrongylus brasiliensis. ELISA analysis showed that N. brasiliensis E/S contained the highest proportion of VIP-like protein (28.04 pmoles/mg of total E/S protein) and A. galli E/S contained the lowest (10.89 pmoles/mg of total E/S protein). Peptide histidine isoleucine (PHI)-like protein was detected by dot blot analysis in the E/S products of N. brasiliensis, N. Battus and A. galli. ELISA analysis suggested that A. galli E/S contained the highest proportion of PHI (20.77 nmoles/mg of total E/S protein) and N. Battus E/S contained the lowest (0.67 nmoles/mg of total E/S protein). The possible significance of VIP-like and PHI-like substances in the E/S of gastrointestinal nematodes is discussed.
Lisa A. Newton - One of the best experts on this subject based on the ideXlab platform.
-
Differences in the second internal transcribed spacer of four species of Nematodirus (Nematoda: Molineidae)☆
International Journal for Parasitology, 1998Co-Authors: Lisa A. Newton, Neil B Chilton, Ian Beveridge, Robin B. GasserAbstract:Abstract Genetic differences among Nematodirus spathiger, Nematodirus filicollis, Nematodirus helvetianus and Nematodirus Battus in the nucleotide sequence of the second internal transcribed spacer (ITS-2) of ribosomal DNA ranged from 3.9 to 24.7%. Pairwise comparisons of their ITS-2 sequences indicated that the most genetically similar species were N. spathiger and N. helvetianus. N. Battus was the most genetically distinct species, with differences ranging from 22.8 to 24.7% with respect to the other three species. Some of the nucleotide differences among species provided different endonuclease restriction sites that could be used in restriction fragment length polymorphism studies. The ITS-2 sequence data may prove useful in studies of the systematics of molineid nematodes.
-
differences in the second internal transcribed spacer of four species of nematodirus nematoda molineidae
International Journal for Parasitology, 1998Co-Authors: Lisa A. Newton, Neil B Chilton, Ian Beveridge, Robin B. GasserAbstract:Genetic differences among Nematodirus spathiger, Nematodirus filicollis, Nematodirus helvetianus and Nematodirus Battus in the nucleotide sequence of the second internal transcribed spacer (ITS-2) of ribosomal DNA ranged from 3.9 to 24.7%. Pairwise comparisons of their ITS-2 sequences indicated that the most genetically similar species were N. spathiger and N. helvetianus. N. Battus was the most genetically distinct species, with differences ranging from 22.8 to 24.7% with respect to the other three species. Some of the nucleotide differences among species provided different endonuclease restriction sites that could be used in restriction fragment length polymorphism studies. The ITS-2 sequence data may prove useful in studies of the systematics of molineid nematodes.
Kevin C Rowe - One of the best experts on this subject based on the ideXlab platform.
-
recent and rapid speciation with limited morphological disparity in the genus rattus
Systematic Biology, 2011Co-Authors: Kevin C Rowe, Ken Aplin, Peter R Baverstock, Craig MoritzAbstract:Recent and rapid radiations provide rich material to examine the factors that drive speciation. Most recent and rapid radiations that have been well-characterized involve species that exhibit overt ecomorphological differences associ- ated with clear partitioning of ecological niches in sympatry. The most diverse genus of rodents, Rattus (66 species), evolved fairly recently, but without overt ecomorphological divergence among species. We used multilocus molecular phylogenetic data and five fossil calibrations to estimate the tempo of diversification in Rattus, and their radiation on Australia and New Guinea (Sahul, 24 species). Based on our analyses, the genus Rattus originated at a date centered on the Pliocene-Pleistocene boundary (1.84-3.17 Ma) with a subsequent colonization of Sahul in the middle Pleistocene (0.85-1.28 Ma). Given these dates, the per lineage diversification rates in Rattus and Sahulian Rattus are among the highest reported for vertebrates (1.1-1.9 and 1.6-3.0 species per lineage per million years, respectively). Despite their rapid diversification, Rattus display little ecomorphological divergence among species and do not fit clearly into current models of adaptive radiations. Lin- eage through time plots and ancestral state reconstruction of ecological characters suggest that diversification of Sahulian Rattus was most rapid early on as they expanded into novel ecological conditions. However, rapid lineage accumulation occurred even when morphological disparity within lineages was low suggesting that future studies consider other pheno- types in the diversification of Rattus. (Adaptive radiation; Australia; chromosomal rearrangements; Molecular systematics; Murinae; New Guinea.)
