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91.
Heterogeneity in environmental conditions helps to maintain genetic and phenotypic
diversity in ecosystems. As such, it may explain why the capacity of animals to mount
immune responses is highly variable. The quality of habitat patches, in terms of
resources, parasitism, predation and habitat fragmentation may, for example, trigger
trade-offs ultimately affecting the investment of individuals in various immunological
pathways. We described spatial immunoheterogeneity in bank vole populations with respect
to landscape features and co-infection. We focused on the consequences of this
heterogeneity for the risk of Puumala hantavirus (PUUV) infection. We assessed the
expression of the Tnf-α and Mx2 genes and demonstrated a negative
correlation between PUUV load and the expression of these immune genes in bank voles.
Habitat heterogeneity was partly associated with differences in the expression of these
genes. Levels of Mx2 were lower in large forests than in fragmented forests,
possibly due to differences in parasite communities. We previously highlighted the
positive association between infection with Heligmosomum mixtum and infection
with PUUV. We found that Tnf-α was more strongly expressed in voles
infected with PUUV than in uninfected voles or in voles co-infected with the
nematode H. mixtum and PUUV. H. mixtum may limit the capacity of the
vole to develop proinflammatory responses. This effect may increase the risk of PUUV
infection and replication in host cells. Overall, our results suggest that close
interactions between landscape features, co-infection and immune gene expression may shape
PUUV epidemiology. 相似文献
92.
93.
W. C. McGrew C. E. G. Tutin D. A. Collins S. K. File 《American journal of primatology》1989,17(2):147-155
Experimental and clinical parasitology need natural baselines or “controls”. We present normative data intestinal parasite loads in two genera of African primates. Wild Pan troglodytes and Papio spp. were studied at two sites: Gombe in Tanzania (P. anubis) and Mt. Assirik in Senegal (P. papio). Presence or absence of parasites, especially nematodes, was recorded from fecal specimens. Gombe's primates were more often infected than were Mt. Assirik's. At Gombe, but not at Mt. Assirik, chimpanzees seemed to have a higher incidence of infection than baboons. Comparison of three baboon troops yielded apparent differences in prevalence of infection. No differences in infection were found between the wet and dry seasons in Mt. Assirik's chimpanzees. 相似文献
94.
In this preliminary survey, coprologic examination of six different captive snake species housed in three different herpetariums of Kerala state was conducted from July 2005 to January 2006, to study the prevalence of endoparasites. Of the 25 snakes examined, 22 (88%) were found infected. On the basis of morphology and morphometry, Capillaria spp. (72%), strongyle (28%), spirurid (20%), Strongyloides/Rhabdias spp. (16%), ascarid (12%), pseudophyllidean tapeworm (8%), acanthocephalan (4%) and pentastomid (12%) ova were identified. The occurrence of ova of Hymenolepis spp. as pseudoparasite was also noticed. Zoo Biol 28:253–258, 2009. © 2009 Wiley-Liss, Inc. 相似文献
95.
Xiaofeng Du Donald P. McManus Juliet D. French Malcolm K. Jones Hong You 《BioEssays : news and reviews in molecular, cellular and developmental biology》2021,43(1)
Recent reports of CRISPR/Cas9 genome editing in parasitic helminths open up new avenues for research on these dangerous pathogens. However, the complex morphology and life cycles inherent to these parasites present obstacles for the efficient application of CRISPR/Cas9‐targeted mutagenesis. This is especially true with the trematode flukes where only modest levels of gene mutation efficiency have been achieved. Current major challenges in the application of CRISPR/Cas9 for study of parasitic worms thus lie in enhancing gene mutation efficiency and overcoming issues involved in host passage so that mutated parasites survive. Strategies developed for CRISPR/Cas9 studies on Caenorhabditis elegans, protozoa and mammalian cells, including novel delivery methods, the choice of selectable markers, and refining mutation precision represent novel tactics whereby these impediments can be overcome. Furthermore, employing CRISPR/Cas9‐mediated gene drive to interfere with vector transmission represents a novel approach for the control of parasitic worms that is worthy of further exploration. 相似文献
96.
Eun-Hee Shin Jae-Hwan Park Sang-Mee Guk Jae-Lip Kim Jong-Yil Chai 《The Korean journal of parasitology》2009,47(2):189-191
Four feral cats and a raccoon dog purchased from a local collector on Aphaedo Island, Shinan-gun, where human Gymnophalloides seoi infections are known to be prevalent, were examined for their intestinal helminth parasites. From 2 of 4 cats, a total of 310 adult G. seoi specimens were recovered. Other helminths detected in cats included Heterophyes nocens (1,527 specimens), Pygidiopsis summa (131), Stictodora fuscata (4), Acanthotrema felis (2), Spirometra erinacei (15), toxocarids (4), and a hookworm (1). A raccoon dog was found to be infected with a species of echinostome (55), hookworms (7), toxocarids (3), P. summa (3), and S. erinacei (1). No G. seoi was found in the raccoon dog. The results indicate that feral cats and raccoon dogs on Aphaedo are natural definitive hosts for intestinal trematodes and cestodes, including G. seoi, H. nocens, and S. erinacei. It has been first confirmed that cats, a mammalian species other than humans, play the role of a natural definitive host for G. seoi on Aphaedo Island. 相似文献
97.
98.
Murray D. Dailey Richard V. Santangelo William G. Gilmartin 《Marine Mammal Science》1988,4(2):125-131
In conjunction with an Hawaiian monk seal, Monachus schauinslandi , breeding enhancement program, fecal samples were examined for the presence of helminth parasite products (eggs, larvae, and proglottids). Eighty-two samples were examined from four island groups in the northwestern Hawaiian Islands: 38 from Kure Atoll, 32 from French Frigate Shoals, 11 from Laysan Island, and one from Lisianski Island. Identified helminth products include those of Diphyllobothrium sp., D. cameroni, Contracaecum turgidum, Anisakis sp., Corynosoma rauschi , and Trematoda. In addition, eggs from Halarachne laysanae (Atari) were found in 3 samples. Eggs of C. turgidum were present in the highest percentage (>64%) of samples from all locations. Eggs of Anisakis sp. and Trematoda are reported from this host for the first time. 相似文献
99.
100.
Patrik G. Flammer Adrian L. Smith 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2020,375(1812)
Enteric helminths are common parasites in many parts of the world and in the past were much more widespread both geographically and socially. Many enteric helminths are relatively long-lived in the human host, often benign or of low pathogenicity while producing large numbers of environmentally resistant eggs voided in the faeces or found associated with individual remains (skeletons and mummies). The combination of helminth characters offers opportunities to the field of historical pathogen research that are quite different to that of some of the more intensively studied high impact pathogens. Historically, a wealth of studies has employed microscopic techniques to diagnose infection using the morphology of the helminth eggs. More recently, various ancient DNA (aDNA) approaches have been applied in the archaeoparasitological context and these are revolutionizing the field, allowing much more specific diagnosis as well as interrogating the epidemiology of helminths. These advances have enhanced the potential for the field to provide unique information on past populations including using diseases to consider many aspects of life (e.g. sanitation, hygiene, diet, culinary practices and other aspects of society). Here, we consider the impact of helminth archaeoparasitology and more specifically the impact and potential for application of aDNA technologies as a part of the archaeologists'' toolkit.This article is part of the theme issue ‘Insights into health and disease from ancient biomolecules’. 相似文献