Skip to main content accessibility help we use cookies to distinguish you from other users and to provide you with a better experience on our websites. Onchocerca ochengi acquisition in zebu gudali cattle exposed to natural transmission. Onchocerciasis, or river blindness, is a parasitic disease that affects more than. Rna from the fluid of nodules of cattle infected with o. Auranofin, approved for use in rheumatoid arthritis, killed both brugia spp. It is the etiologic agent of human onchocerciasis and is transmitted by the bites of blackflies buffalo gnats of the. Lim 0 1 nonglak supakorndej 0 1 prasit supakorndej 0 1 alan r. Onchocerca volvulus is a filarial arthropodborne nematode roundworm that causes. Onchocerca ochengi microfilarial hamster model for onchocerciasis drug screens. Aug 14, 2017 onchocerciasis is one of the tropical neglected diseases ntds caused by the nematode onchocerca volvulus. The biology of onchocerca ochengi, a filarial nematode. However, its lack of an adaptive immune system clearly undermines the possible assisting role. The flies were maintained for 10 days with 15 % sucrose at 23 c with the mortality rate being recorded daily. Sig nificantly, simulium darnnosum, the vector of the important human parasite, o.
The role of wolbachia in the pathogenesis of river blindness murine model. Antionchocerca activity and phytochemical analysis of an. Sep 01, 2014 in vitro activity of cameroonian and ghanaian medicinal plants on parasitic onchocerca ochengi and free living caenorhabditis elegans nematodes. This is also supported by genetic data that place o. The three most active extracts on onchocerca ochengi females were also highly active on loa loa microfilariae, with ic50s of 35. Over 40 million people are infected in africa, central america, and south america. Jul 01, 2019 ochengi adult male worms in vitro from worm masses removed from infected cattle skin, b cluster of free o.
Further evidence of the crossreactivity of the binax now. Small rna libraries were prepared from total rna extracted from the nodule fluid of cattle infected with onchocerca ochengi as well as serum and plasma from humans infected with onchocerca volvulus in cameroon and ghana. The plant extract and all of the pure tested compounds were active against o. Loa loa and onchocerca ochengi mirnas detected in host. In its local use, the roots and rhizomes of the plant are chopped, dried, boiled in water and taken as a decoction. Onchocerca ochengi, a bovine parasite of zebu cattle in africa is the closest related species to o. Onchocerca ochengi and the free living nematode caenorhabditis elegans were used as the model nematode parasites. In order to assess the prevalence of the cattle filaria onchocerca ochengi in onchocerciasis vectors simulium damnosum s. Publications study of onchocerciasis programme onchocercoses. Characterization of a novel glycosylated glutathione.
Pdf onchocerca ochengi infections in cattle as a model for human. Pdf macrofilaricidal activity of tetracycline against. Stagespecific proteomes from onchocerca ochengi, sister. Successful vaccination against onchocerca ochengi infestation in cattle using live onchocerca volvulus infective larvae. Onchocerciasis is a devastating, vector borne, neglected tropical. Research article open access onchocerca ochengi activities of. Igg1 and lgg2 antibodies to ov10ov11 recombinant onchocerca antigens were invoked by nonvaccinatedchallenged animals but not by most 80% of. The activity was evaluated on the mfs and adult worms of onchocerca ochengi,the closest relative ofo. Characterization of the genomes of the parasite onchocerca volvulus, the causative agent. Dec 15, 2006 epidemiological evidence has led to the hypothesis that the concurrent and predominant transmission of onchocerca ochengi by simulium damnosum s.
The vaccinatedchallenged animals had 8387% less adult o. In both, humans and cattle, some individuals are nearly or completely free from. Onchocerca from wikipedia, the free encyclopedia onchocerca is a genus of parasitic roundworm. Blackwell publishing ltdoriginal articlevaccination. Phytochemical analysis and in vitro anthelmintic activity of. Pdf in vitro activity of cameroonian and ghanaian medicinal. Onchocerciasis, caused by the parasitic nematode, onchocerca volvulus afflicts some 37 million people worldwide, and is the second leading infectious cause of blindness globally. Animal models onchocerca ochengi and the development of chemotherapeutic and chemoprophylactic agents for onchocerciasis. Pool screen polymerase chain reaction for estimating. Onchocerca ochengi is a filaria genetically closely related to the human parasite onchocerca volvulus 29.
Extracellular onchocercaderived small rnas in host. Onchocerca species have a wide geographical distribution, and the disease they produce, onchocerciasis, is generally seen in adult individuals because of its large prepatency period. The flies were maintained for 10 days with 15 % sucrose at 23. By microinjection of cryopreserved microfilariae mf into nulliparous flies, a comparison of the lengths of the infective larvae l 3 of onchocerca volvulus and o. Ndjonka d, ajoninaekoti l, djafsia b, luersen k, abladam e, liebau e. Onchocerca ochengi is the closest species to onchocerca volvulus, the human parasite, with which it shares the same vector and presents an identical pathological manifestation, such as nodule formation achukwi et al. The effect of three phenols ellagic, gentisic and gallic acids from the axlewood tree anogeissus leiocarpus on onchocerca ochengi and drugresistant strains of caenorhabditis elegans, a model organism for research on nematode parasites, is investigated. The ethanolic extract of anogeissus leiocarpus was assessed for the in vitro anthelmintic activity by using the cattle parasite nematode onchocerca ochengi as well as levamisole, ivermectin and albendazoleresistant mutant strains of the free living nematode caenorhabditis elegans, a model organis. In cameroon it serves as an animal model to study the vectorborne disease, transmitted by the same black fly. Research open access discrimination between onchocerca.
Population genetic studies in the parasitic nematode. Ongoing transmission of onchocerca volvulus after 25 years. Rascn 0 1 jr 0 1 nancy tricoche 0 1 moses samje 0 1 aaron bell 0 1 brian suzuki 0 1 k. Onchocerca ochengi transmission dynamics and the correlation of o. Alternative treatment strategies to accelerate the.
Antibiotic chemotherapy of onchocerciasis oxford academic. Aug 30, 2016 the methylene chloride extract of piper umbellatum leaves was the most active on adult male and female worms ic50s. Onchocerciasis or river blindness is a parasitic disease. Filaricidal activities on onchocerca ochengi and loa loa. Onchocerca infected cattle produce strong antibody. Pdf ventral skin biopsies from 204 gudali cattle of the vina division in the adamawa highlands revealed. Anogeissus leiocarpus extract on the parasite nematode onchocerca ochengi and on drug resistant strains of the free living nematode caenorhabditis elegans. Pdf bovine onchocercosis in north cameroon researchgate. Stagespecific proteomes from onchocerca ochengi, sister species of the human river. Onchocerca ochengi, a filarial parasite of cattle, is the closest relative of o. Since vaccine and safe macrofilaricidal treatment against onchocerciasis are still. Extracellular onchocerca derived small rnas in host nodules. The clinical signs of onchocerciasis in man vary from mild to hyperreactive forms. The genus onchocerca includes several species associated with ungulates as hosts, although some have been identified in canids, felids, and humans.
Development and validation of an onchocerca ochengi. Onchocerciasis and its control world health organization. Extracellular onchocerca derived small rnas in host. Here we identify extracellular, parasitederived small rnas associated with onchocerca species infecting cattle and humans. In vitro activity of cameroonian and ghanaian medicinal plants on parasitic onchocerca ochengi and free living caenorhabditis elegans nematodes september 2011 journal of helminthology 853. Genomics of loa loa, a wolbachiafree filarial parasite of humans. February repurposing auranofin as a lead candidate for treatment of lymphatic filariasis and onchocerciasis christina a. The genome of onchocerca volvulus, agent of river blindness. It is the secondmost common cause of blindness due to infection, after trachoma the parasite worm is spread by the bites of a black fly of the simulium type. In vitro anti onchocerca ochengi activities of extracts and chromatographic fractions of craterispermum laurinum and morinda lucida moses samje1,2, jonathan metuge2, james mbah3, brice nguesson3 and fidelis chongwa2 abstract background. Plant was extracted in ethanol or methanolmethylene chloride. Bidlow 0 1 sara lustigman 0 1 fidelis chongwa 0 1 david williams 0 1 alberto a. Onchocerca ochengi and the anthelmintic drug resistant strains of the free living nematode caenorhabditis elegans and to determine the phytochemical profiles of the extracts and fractions of the plants. Development and validation of an onchocerca ochengi adult.
The es products were generated from adult male and female worms in vitro and analyzed with poly. Macrofilaricidal activity of tetracycline against the filarial nematode onchocerca ochengi. Onchocerca ochengi, a bovine parasite of zebu cattle in africa is the. Saharan africa could lead to the protection of humans against onchocerciasis caused by onchocerca volvulus zooprophylaxis. In vitro antionchocerca ochengi activities of extracts and. Successful vaccination against onchocerca ochengi infestation in. Pdf repeated high doses of avermectins cause prolonged. Oct 10, 2016 background genetic surveillance of the human filarial parasite, onchocerca volvulus, from onchocerciasis endemic regions will ideally focus on genotyping individual infective larval stages collected from their intermediate host, simuliid blackflies. Onchocerca infected cattle produce strong antibody responses to. Molecular evidence of siisa form, a new genotype related to onchocerca ochengi in cattle from north cameroon albert eisenbarth, david ekale, julia hildebrandt, mbunkah daniel achukwi, adrian streit, alfons renz acta tropica 127 20 261265 reproductive biology of onchocerca ochengi, a nodule forming filarial nematode in zebu cattle. Onchocerca ochengi fidelis chongwa, melanie abongwa, moses n ngemenya, kennedy d nyongbela abstract background. Onchocerciasis caused by onchocerca volvulus is the worlds second leading infectious cause of blindness.
Two populations were observed between 2030 nt and 5070 nt figure 1, similar to the small rna profile previously observed for the in vitro secretion products of the gastrointestinal nematode h. Research article open access selective activity of. The biology of onchocerca ochengi, a filarial nematode from. Onchocerca ochengi is a common filarial parasite in african zebu cattle, which is nonpathogenic, in contrast to its closest known relative onchocerca volvulus, which causes onchocerciasis river blindness in humans. Immune recognition of excretory and secretory products of the.
In vitro activity of cameroonian and ghanaian medicinal plants on parasitic onchocerca ochengi and free living caenorhabditis elegans nematodes. Nov 01, 2014 a combination of deepsequencing and bioinformatics analysis enabled identification of twentytwo microrna candidates of potential nematode origin in plasma from loa loainfected baboons and a further ten from the plasma of an onchocerca ochengi infected cow. Onchocerca ochengi microfilarial hamster model for onchocerciasis drug screens glory enjong mbah, rene bilingwe ayiseh and fidelis chongwa abstract background. Furthermore, the development of resistance to ivermectin was observed. In recent years, onchocerca species infecting animals have been. Economic losses resulting from bovine onchocerciasis rarely have been.
Anthelmintic activity of phenolic acids from the axlewood tree anogeissus leiocarpus on the filarial nematode onchocerca ochengi and drugresistant strains of the free living nematode caenorhabditis elegans j helminthol. Successful vaccination against onchocerca ochengi infestation. Phytochemical composition and anthelmintic activities of. Onchocerca volvulus with implications for anti onchocerca drug. The current treatment of onchocerciasis relies on the use of ivermectin which is only microfilaricidal and for which resistant parasite strains of veterinary importance are increasingly being detected. Anogeissus leiocarpus extract on the parasite nematode. Dec 01, 2016 the onchocerca ochengi system has consistently shown that strong, albeit incomplete, natural immunity exists in cattle and that partial protection can be induced by both irradiated and recombinant vaccines. However, blackflies also transmit other onchocerca species, including the cattle parasite o. On the basis of both morphological and molecular criteria, o. Control strategies currently in use rely on mass administration of ivermectin, which has marked activity against microfilariae.
Glory enjong mbah, rene bilingwe ayiseh and fidelis chongwa. The present study was conducted to investigate macrofilaricidal properties of ficus sycomorusin vitro against the bovine filarial worm. However, other species of the genus onchocerca are all parasites of ungulates and we have developed the african bovine species, o. Clinical, eeg and imaging studies and 2 yr outcomes of oae. Pdf the bovine parasite onchocerca ochengi is a noduledwelling filarial nematode, closely related to o. Morphometric differentiation of onchocerca volvulus and o.
Phytochemical analysis and in vitro anthelmintic activity. Introduction the cattle filarial nematode onchocerca ochengi is a wellestablished model natural system for the study of human onchocerciasis, the causative agent of which is o. Nematocidal activity on onchocerca ochengi, toxicity and. The ethanolic extract of anogeissus leiocarpus was assessed for the in vitro anthelmintic activity by using the cattle parasite nematode onchocerca ochengi as well as levamisole, ivermectin and albendazoleresistant mutant strains of the free living nematode caenorhabditis elegans, a model organism for research on nematode parasites.
Symptoms include severe itching, bumps under the skin, and blindness. Trees the cattle parasite, onchocerca ochengi, is widely distributed in west africa. Pdf macrofilaricidal activity of tetracycline against the. Anthelmintic activity of phenolic acids from the axlewood. It contains one human parasite onchocerca volvulus which is responsible for the neglected disease onchocerciasis, also known as river blindness because the infected humans tend to live near rivers where host black flies live. Development and validation of an onchocerca ochengi microfilarial. Extracellular onchocercaderived small rnas in host nodules. Repurposing auranofin as a lead candidate for treatment of. Onchocerca ochengi definition of onchocerca ochengi by. Both systems are useful, but not exact, animal models. Although of limited veterinary significance, onchocerca ochengi has become famous as a natural model or analogue of human onchocerciasis river blindness, which is caused by onchocerca volvulus. While high lc50 were required for the effects of the compounds on c.
On the basis of both morphological cattle and molecular criteria, o. This study describes a versatile approach to discriminate between o. Stagespecific proteomes from onchocerca ochengi, sister species. The freeliving nematode caenorhabditis elegans remains the most. Subcutaneous immunisation with onchocerca volvulus antigens, which is a model for chronic infection, stimulates the.
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