[investigations on the filariidae of the cervidae in southern germany. 1. development of the nodule, finding of the sexes and production of the microfilariae in onchocerca flexuosa (wedl, 1856), in the red deer (cervus elaphus) (author's transl)].the biology of o. flexuosa was studied during the examination of numerous subcutaneous nodules, which were taken from the hides of red deer of all age-classes. in fawns the development of the nodule is induced by the immature stages, probably by the females. at the same time a hematome is formed. males of different ages penetrate into the nodule where mature or immature females are present. later they mate and remain within the nodule until the microfilariae in the uteri of the females develop. ...19751145726
lymph nodes of red deer infected with subcutaneous filariae wehrdikmansia cervipedis (wehr et dikmans, 1935) and onchocerca flexuosa (wedl, 1856). 19705530018
neutrophil accumulation around onchocerca worms and chemotaxis of neutrophils are dependent on wolbachia endobacteria.unlike in many other helminth infections, neutrophilic granulocytes are major cellular components in the hosts immune response against filarial worms. the pathways that drive the immune response involving neutrophils are unclear. this study shows that wolbachia endobacteria (detectable by polyclonal antibodies against endobacterial heat shock protein 60 and catalase and by polymerase chain reaction being sensitive to doxycycline treatment) are direct and indirect sources of signals accounting fo ...200111377205
the filarial endosymbiont wolbachia sp. is absent from setaria equina.wolbachia sp. was first reported in filarial nematodes over 25 yr ago. today, much research is focused on the role of these bacteria in filarial worm biology. the filarial symbionts are closely related to arthropod symbionts, which are known to modify host reproduction and biology through various mechanisms. similarly, it has been suggested that wolbachia sp. is essential for long-term survival and reproduction of filariae. we report that wolbachia sp. 16s rdna was not found in the equine filari ...200212537121
evidence against wolbachia symbiosis in loa loa.background: the majority of filarial nematode species are host to wolbachia bacterial endosymbionts, although a few including acanthocheilonema viteae, onchocerca flexuosa and setaria equina have been shown to be free of infection. comparisons of species with and without symbionts can provide important information on the role of wolbachia symbiosis in the biology of the nematode hosts and the contribution of the bacteria to the development of disease. previous studies by electron microscopy and ...200312816546
the nematode parasite onchocerca volvulus generates the transforming growth factor-beta (tgf-beta).transforming growth factor-beta (tgf-beta) is a highly conserved cytokine that has a well-known regulatory role in immunity, but also in organ development of most animal species including helminths. homologous tgf-b genes and mrna have been detected in the filaria brugia malayi. the in situ protein expression is unknown for filariae. therefore, we examined several filariae for the expression and localization of latent (stable) tgf-beta in adult and larval stages. a specific goat anti-human laten ...200919452170
endosymbiont dna in endobacteria-free filarial nematodes indicates ancient horizontal genetic transfer.wolbachia are among the most abundant symbiotic microbes on earth; they are present in about 66% of all insect species, some spiders, mites and crustaceans, and most filarial nematode species. infected filarial nematodes, including many pathogens of medical and veterinary importance, depend on wolbachia for proper development and survival. the mechanisms behind this interdependence are not understood. interestingly, a minority of filarial species examined to date are naturally wolbachia-free.201020543958
first description of nodular onchocercosis (onchocerca jakutensis) in free-ranging italian red deer (cervus elaphus).onchocercosis is a vector-transmitted parasitic disease involving wild and domestic ungulates, humans, and dogs. red deer (cervus elaphus) host numerous onchocerca spp. which have precise anatomic sites in the host and two species, onchocerca flexuosa wedl, 1856 and onchocerca jakutensis guba-now, 1964, are found inside subcutaneous nodules. between september and november 2007, subcutaneous nodules were observed on both thighs in shot red deer of a tuscany population. we observed cystic structur ...201122102667
localization of wolbachia-like gene transcripts and peptides in adult onchocerca flexuosa worms indicates tissue specific expression.most filarial species in the genus onchocerca depend on wolbachia endobacteria to successfully carry out their life cycle. o. flexuosa is a wolbachia-free species, but its genome contains wolbachia-like sequences presumably obtained from wolbachia via horizontal gene transfer. proteogenomic studies have shown that many of these wolbachia-like sequences are expressed in adult worms.201323281896
transcriptomic and proteomic analyses of a wolbachia-free filarial parasite provide evidence of trans-kingdom horizontal gene transfer.most filarial parasites in the subfamilies onchocercinae and dirofilariinae depend on wolbachia endobacteria to successfully carry out their life cycle. recently published data indicate that the few wolbachia-free species in these subfamilies were infected in the distant past and have subsequently shed their endosymbionts. we used an integrated transcriptomic and proteomic analysis of onchocerca flexuosa to explore the molecular mechanisms that allow worms of this species to survive without a ba ...201223049857
comparing the mitochondrial genomes of wolbachia-dependent and independent filarial nematode species.many species of filarial nematodes depend on wolbachia endobacteria to carry out their life cycle. other species are naturally wolbachia-free. the biological mechanisms underpinning wolbachia-dependence and independence in filarial nematodes are not known. previous studies have indicated that wolbachia have an impact on mitochondrial gene expression, which may suggest a role in energy metabolism. if wolbachia can supplement host energy metabolism, reduced mitochondrial function in infected filar ...201222530989
levels of infection, pathology and nodule size of onchocerca flexuosa (nematoda: onchocercidae) in red deer (cervus elaphus) from northern spain.between 2005 and 2007, the presence of onchocerca flexuosa (wedl, 1856) was discovered and investigated in 110 red deer (cervus elaphus) shot in the riaño regional hunting reserve, in the province of león (north-western spain). nodules containing o. flexuosa were located in the dorsal region and flanks of the deer. these were collected and measured, and some adult parasites were extracted from the nodules and identified by morphology and by obtaining mitochondrial 12s rdna sequences, which were ...201524622346
first description of onchocerca jakutensis (nematoda: filarioidea) in red deer (cervus elaphus) in switzerland.twenty-seven species of the genus onchocerca (nematoda; filarioidea) can cause a vector-borne parasitic disease called onchocercosis. most onchocerca species infect wild and domestic ungulates or the dog, and one species causes river blindness in humans mainly in tropical africa. the european red deer (cervus e. elaphus) is host to four species, which are transmitted by blackflies (simuliids) or biting midges (ceratopogonids). two species, onchocerca flexuosa and onchocerca jakutensis, produce s ...201627617204
onchocercosis in red deer (cervus elaphus) from spain.onchocercosis, caused by onchocerca flexuosa, was observed in red deer (cervus elaphus) from spain for the first time. adult specimens of p. flexuosa were found in nodules in subcutaneous tissues in 42 of 125 (33%) red deer between october 1994 and september 1995; intensity of infection +/- sd was 3.93 +/- 5.26 nodules per infected host. a clear seasonal pattern in the distribution of nodules was observed, with higher values of prevalence and intensity in fall and winter in contrast to spring an ...200111695405
Displaying items 1 - 14 of 14