Prevalence, risk factors and spatial analysis of liver fluke infections in Danish cattle herds

DEFF Research Database (Denmark)

Olsen, Abbey; Frankena, Klaas; Bødker, Rene

2015-01-01

Background: Fasciola hepatica, a trematode parasite (liver fluke), infects a wide range of host species causing fasciolosis. The disease is prevalent world-wide and causes considerable economic losses to the livestock industry. Fasciolosis is regarded as an emerging food-borne zoonosis. To promote...... awareness among farmers and to implement strategies to control the infection, this study examined the prevalence, spatial distribution and risk factors for Fasciola hepatica infection in Danish cattle herds. Methods: A retrospective population based study was performed using meat inspection data...... of approximately 1.5 million cattle slaughtered in the period 2011 to 2013. Annual cumulative prevalence of recorded liver fluke findings was calculated for each year. Global and local spatial cluster analysis was used to identify and map spatial patterns of Fasciola hepatica positive and negative herds to explore...

Approaches to genotyping individual miracidia of Schistosoma japonicum

OpenAIRE

Xiao, Ning; Remais, Justin V.; Brindley, Paul J.; Qiu, Dong-chuan; Carlton, Elizabeth J.; Li, Rong-zhi; Lei, Yang; Blair, David

2013-01-01

Molecular genetic tools are needed to address questions as to the source and dynamics of transmission of the human blood fluke Schistosoma japonicum in regions where human infections have re-emerged, and to characterize infrapopulations in individual hosts. The life-stage that interests us as a target for collecting genotypic data is the miracidium, a very small larval stage that consequently yields very little DNA for analysis. Here, we report the successful development of a multiplex format...

Presence and species identity of rumen flukes in cattle and sheep in the Netherlands.

Science.gov (United States)

Ploeger, H W; Ankum, L; Moll, L; van Doorn, D C K; Mitchell, G; Skuce, P J; Zadoks, R N; Holzhauer, M

2017-08-30

The purpose of the study was to gain knowledge about the prevalence and identity of rumen flukes (RF) in cattle and sheep in the Netherlands. Routine faecal examinations of diagnostic submissions between May 2009 and September 2014 showed a mean annual herd or flock RF prevalence of 15.8% for cattle and 8.0% for sheep. Prevalence in cattle was higher after 2012 than before, which may reflect a change in detection method as well as an increase in true prevalence. During November and December 2014, an abattoir survey was conducted to allow for scoring of rumen fluke burden and to obtain specimens for molecular species characterization. Over 8 visits to 5 abattoirs in areas deemed to pose a high risk for trematode infection, 116 cows and 41 sheep from 27 herds and 10 flocks were examined. Prevalence of RF was higher in beef cattle than in dairy cattle and higher in cattle than in sheep. Median fluke burden was >100 specimens per animal for most positive animals. Using a semi-quantitative RF density score as a gold standard, sensitivity and specificity of a modified quantitative Dorsman egg counting method were estimated at 82.6% and 83.3%, respectively. Of 14 collected adult rumen flukes, twelve (8 bovine and 4 ovine specimens) were identified as Calicophoron daubneyi. The other two, of bovine origin, were identified as Paramphistomum leydeni, which was unexpected as in other European countries all recently collected rumen flukes in both cattle and sheep were identified as C. daubneyi. The findings implicate that multiple rumen fluke species, intermediate host species and transmission cycles may play a role in rumen fluke infections in the Netherlands. Copyright © 2017. Published by Elsevier B.V.

Poultry as reservoir hosts for fishborne zoonotic trematodes in Vietnamese fish farms.

Science.gov (United States)

Anh, Nguyen Thi Lan; Madsen, Henry; Dalsgaard, Anders; Phuong, Nguyen Thi; Thanh, Dao Thi Ha; Murrell, K Darwin

2010-05-11

Fishborne zoonotic trematodes (FZT) are widespread in Vietnam and Southeast Asia. It is now recognized that the risk of being infected from eating raw fish dishes applies not only to humans, but also to domestic animals (e.g., cats, dogs, and pigs) and fish-eating birds. The role of ducks and chicken, commonly raised on fish farms, as reservoir hosts, however, has not been adequately investigated. To study this question, chickens and ducks from integrated poultry-fish farms in Nghia Lac and Nghia Phu communes, Nam Dinh province, Vietnam were surveyed for FZT infections. A total of 50 ducks and 50 chickens from each commune were examined. Results revealed that 12% of chickens and 30% of ducks were infected with various species of trematodes, including two zoonotic species, Centrocestus formosanus and Echinostoma cinetorchis. Both occurred in chickens whereas only E. cinetorchis was found in ducks. Prevalence of these zoonotic species was 12% and 7% in ducks and chickens, respectively. Among other trematodes, Hypoderaeum conoideum, also a zoonotic fluke, was the most prevalent (20-30%). The feeding of snails and fish remains to poultry, either intentionally or by discharge of waste from the slaughter of ducks and chickens into the ponds, was identified as risk factors for trematode infection. The FZT species and low prevalence found in poultry in these communes indicate their role as reservoir hosts is minor. (c) 2010 Elsevier B.V. All rights reserved.

Eye trematode infection in small passerines in Peru caused by Philophthalmus lucipetus, an agent with a zoonotic potential spread by an invasive freshwater snail

Czech Academy of Sciences Publication Activity Database

Literák, I.; Heneberg, P.; Sitko, J.; Wetzel, E. J.; Callirgos, J. M. C.; Čapek, Miroslav; Basto, D. V.; Papoušek, I.

2013-01-01

Roč. 62, č. 4 (2013), s. 390-396 ISSN 1383-5769 R&D Projects: GA AV ČR IAA601690901; GA MŠk LC06073 Institutional support: RVO:68081766 Keywords : Birds * Caenogastropoda * Digenea * DNA analysis * Echinostomida * Eye trematode * Fluke Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.111, year: 2013

Cloning the genes and DNA binding properties of high mobility group B1 (HMGB1) proteins from the human blood flukes Schistosoma mansoni and Schistosoma japonicum

Czech Academy of Sciences Publication Activity Database

De Oliveira, F.M.B.; Da Silva, I.C.dA.; Rumjanek, F.D.; Dias-Neto, E.; Guimaraes, P.E.M.; Verjovski-Almeida, S.; Štros, Michal; Fantappié, M.R.

2006-01-01

Roč. 377, - (2006), s. 33-45 ISSN 0378-1119 R&D Projects: GA ČR(CZ) GA204/05/2031 Institutional research plan: CEZ:AV0Z50040507 Keywords : HMGB1 * Schistosoma mansoni * Schistosoma japonicum Subject RIV: BO - Biophysics Impact factor: 2.721, year: 2006

Gene discovery for the carcinogenic human liver fluke, Opisthorchis viverrini

Directory of Open Access Journals (Sweden)

Gasser Robin B

2007-06-01

Full Text Available Abstract Background Cholangiocarcinoma (CCA – cancer of the bile ducts – is associated with chronic infection with the liver fluke, Opisthorchis viverrini. Despite being the only eukaryote that is designated as a 'class I carcinogen' by the International Agency for Research on Cancer, little is known about its genome. Results Approximately 5,000 randomly selected cDNAs from the adult stage of O. viverrini were characterized and accounted for 1,932 contigs, representing ~14% of the entire transcriptome, and, presently, the largest sequence dataset for any species of liver fluke. Twenty percent of contigs were assigned GO classifications. Abundantly represented protein families included those involved in physiological functions that are essential to parasitism, such as anaerobic respiration, reproduction, detoxification, surface maintenance and feeding. GO assignments were well conserved in relation to other parasitic flukes, however, some categories were over-represented in O. viverrini, such as structural and motor proteins. An assessment of evolutionary relationships showed that O. viverrini was more similar to other parasitic (Clonorchis sinensis and Schistosoma japonicum than to free-living (Schmidtea mediterranea flatworms, and 105 sequences had close homologues in both parasitic species but not in S. mediterranea. A total of 164 O. viverrini contigs contained ORFs with signal sequences, many of which were platyhelminth-specific. Examples of convergent evolution between host and parasite secreted/membrane proteins were identified as were homologues of vaccine antigens from other helminths. Finally, ORFs representing secreted proteins with known roles in tumorigenesis were identified, and these might play roles in the pathogenesis of O. viverrini-induced CCA. Conclusion This gene discovery effort for O. viverrini should expedite molecular studies of cholangiocarcinogenesis and accelerate research focused on developing new interventions

Use of ionizing radiation in the development of vaccines against Fasciola gigantica and Schistosoma bovis in Sudanese cattle, sheep and goats

International Nuclear Information System (INIS)

Haroun, E.M.; Yagi, A.I.; Younis, S.A.; El Sanhouri, A.A.; Gadir, H.A.; Gameel, A.A.; Bushara, H.O.

1988-01-01

A primary infection with Fasciola gigantica, which had been eliminated by anthelmintic treatment after eight weeks, stimulated partial resistance to homologous challenge in calves and goats. Similar sensitization with F. gigantica or Schistosoma bovis also stimulated significant resistance to heterologous challenge in calves. The level of resistance was indicated by reduced fluke recoveries from sensitized animals compared with controls, by lower values of the enzymes sorbitol dehydrogenase and glutamate dehydrogenase, indicating less hepatic damage, and by lower blood indices, indicating more severe anaemia. Infection of calves with metacercariae of F. gigantica irradiated at 30 Gy or 200 Gy resulted in mean fluke recoveries of 75 and 41 respectively, whereas 332 flukes were recovered from controls infected with non-irradiated metacercariae. The flukes recovered from animals infected with irradiated metacercariae were stunted and resided in the small bile ductules. Sensitization for eight weeks with metacercariae of F. gigantica irradiated at 30 Gy resulted in significant resistance in calves, sheep and goats to homologous challenge. Significant resistance was also stimulated in calves by sensitization for eight weeks with metacercariae of F. gigantica irradiated at 200 Gy. However, sensitization for four weeks with F. gigantica irradiated at 30 Gy failed to stimulate significant resistance in calves to homologous challenge, but similar sensitization, twice at an interval of four weeks, resulted in an average reduction of 62% in fluke recovery from calves with homologous challenge. This reduction was, however, statistically insignificant. Moreover, sensitization for eight weeks with cercariae of Schistosoma bovis irradiated at 30 Gy did not stimulate heterologous resistance in calves or goats to F. gigantica. A similar result was also obtained after sensitization of calves for 36 weeks with cercariae of S. bovis irradiated at 30 Gy before challenge with F

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia.

Science.gov (United States)

Sissay, Menkir M; Uggla, Arvid; Waller, Peter J

2007-10-01

A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger Oesopha-gostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the

Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum.

Directory of Open Access Journals (Sweden)

Pengfei Cai

2016-04-01

Full Text Available Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes of the genus Schistosoma. Schistosomes are sexually dimorphic and exhibit dramatic morphological changes during a complex lifecycle which requires subtle gene regulatory mechanisms to fulfil these complex biological processes. In the current study, a 41,982 features custom DNA microarray, which represents the most comprehensive probe coverage for any schistosome transcriptome study, was designed based on public domain and local databases to explore differential gene expression in S. japonicum. We found that approximately 1/10 of the total annotated genes in the S. japonicum genome are differentially expressed between adult males and females. In general, genes associated with the cytoskeleton, and motor and neuronal activities were readily expressed in male adult worms, whereas genes involved in amino acid metabolism, nucleotide biosynthesis, gluconeogenesis, glycosylation, cell cycle processes, DNA synthesis and genome fidelity and stability were enriched in females. Further, miRNAs target sites within these gene sets were predicted, which provides a scenario whereby the miRNAs potentially regulate these sex-biased expressed genes. The study significantly expands the expressional and regulatory characteristics of gender-biased expressed genes in schistosomes with high accuracy. The data provide a better appreciation of the biological and physiological features of male and female schistosome parasites, which may lead to novel vaccine targets and the development of new therapeutic interventions.

Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum.

Science.gov (United States)

Cai, Pengfei; Liu, Shuai; Piao, Xianyu; Hou, Nan; Gobert, Geoffrey N; McManus, Donald P; Chen, Qijun

2016-04-01

Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomes are sexually dimorphic and exhibit dramatic morphological changes during a complex lifecycle which requires subtle gene regulatory mechanisms to fulfil these complex biological processes. In the current study, a 41,982 features custom DNA microarray, which represents the most comprehensive probe coverage for any schistosome transcriptome study, was designed based on public domain and local databases to explore differential gene expression in S. japonicum. We found that approximately 1/10 of the total annotated genes in the S. japonicum genome are differentially expressed between adult males and females. In general, genes associated with the cytoskeleton, and motor and neuronal activities were readily expressed in male adult worms, whereas genes involved in amino acid metabolism, nucleotide biosynthesis, gluconeogenesis, glycosylation, cell cycle processes, DNA synthesis and genome fidelity and stability were enriched in females. Further, miRNAs target sites within these gene sets were predicted, which provides a scenario whereby the miRNAs potentially regulate these sex-biased expressed genes. The study significantly expands the expressional and regulatory characteristics of gender-biased expressed genes in schistosomes with high accuracy. The data provide a better appreciation of the biological and physiological features of male and female schistosome parasites, which may lead to novel vaccine targets and the development of new therapeutic interventions.

Mucocutaneous manifestations of helminth infections: Trematodes and cestodes.

Science.gov (United States)

Lupi, Omar; Downing, Christopher; Lee, Michael; Bravo, Francisco; Giglio, Patricia; Woc-Colburn, Laila; Tyring, Stephen K

2015-12-01

In the 21st century, despite increased international travel for vacation, work, and medical missions and immigration into the United States, there is little published in the dermatology literature regarding the cutaneous manifestations of helminth infections. It has been estimated that 20% to 70% of international travelers suffer from some travel-related health problem. Approximately 17% of travelers seek medical care because of cutaneous disorders, many related to infectious etiologies. This review will focus on cutaneous diseases caused by helminth infections. Part I of the review focused on nematode infections; part II will focus on trematode and cestode infections. Nematodes are roundworms that cause diseases with cutaneous manifestations, such as cutaneous larval migrans, onchocerciasis, filariasis, gnathostomiasis, loiasis, dracunculiasis, strongyloidiasis, ascariasis, streptocerciasis, dirofilariasis, and trichinosis. Tremadotes, also known as flukes, cause schistosomiasis, paragonimiasis, and fascioliasis. Cestodes (tapeworms) are flat, hermaphroditic parasites that cause diseases such as sparganosis, cysticercosis, and echinococcus. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Trypsin- and Chymotrypsin-Like Serine Proteases in Schistosoma mansoni - 'The Undiscovered Country'

Czech Academy of Sciences Publication Activity Database

Horn, Martin; Fajtová, Pavla; Arreola, L. R.; Ulrychová, Lenka; Bartošová-Sojková, Pavla; Franta, Zdeněk; Protasio, A. V.; Opavský, David; Vondrášek, Jiří; McKerrow, J. H.; Mareš, Michael; Caffrey, C. R.; Dvořák, Jan

2014-01-01

Roč. 8, č. 3 (2014), e2766/1-e2766/13 ISSN 1935-2735 R&D Projects: GA ČR(CZ) GAP302/11/1481; GA MŠk(CZ) ME10011 EU Projects: European Commission(XE) 248642 - SCHISTOSOMA PROTEASE Institutional support: RVO:61388963 ; RVO:68378050 ; RVO:60077344 Keywords : schistosomiasis * blood fluke * serine protease Subject RIV: CE - Biochemistry; EB - Genetics ; Molecular Biology (UMG-J); FN - Epidemiology, Contagious Diseases ; Clinical Immunology (BC-A) Impact factor: 4.446, year: 2014 http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0002766

Schistosome and liver fluke derived catechol-estrogens and helminth associated cancers

Directory of Open Access Journals (Sweden)

José M Correia da Costa

2014-12-01

Full Text Available Infection with helminth parasites remains a persistent public health problem in developing countries. Three of these pathogens, the liver flukes Clonorchis sinensis, Opisthorchis viverrini and the blood fluke Schistosoma haematobium, are of particular concern due to their classification as Group 1 carcinogens: infection with these worms is carcinogenic. Using liquid chromatography-mass spectrometry (LC-MS/MS approaches, we identified steroid hormone like (e.g. oxysterol-like, catechol estrogen quinone-like, etc. metabolites and related DNA-adducts, apparently of parasite origin, in developmental stages including eggs of S. haematobium, in urine of people with urogenital schistosomiasis, and in the adult stage of Opisthorchis viverrini. Since these kinds of sterol derivatives are metabolized to active quinones that can modify DNA, which in other contexts can lead to breast and other cancers, helminth parasite associated sterols might induce tumor-like phenotypes in the target cells susceptible to helminth parasite associated cancers, i.e. urothelial cells of the bladder in the case of urogenital schistosomiasis and the bile duct epithelia or cholangiocytes, in the case of O. viverrini and C. sinensis. Indeed we postulate that helminth induced cancers originate from parasite estrogen-host epithelial/urothelial cell chromosomal DNA adducts, and here we review recent findings that support this conjecture.

Biodiversity of flukes

Directory of Open Access Journals (Sweden)

Dreyfuss G.

2008-09-01

Full Text Available As many others parasites, speciation of flukes depends on the genetic characteristics and on ploidia. Ploidia of flukes can be different in a same species. In Asia, diploid, triploid and hybrid (2n/3n populations are encountered. The comparison of morphological parameters between diploid and triploid flukes showed that they were morphologically different. Nevertheless, a genetic relationship between parthenogenetic organisms would exist regardless of their ploidia. In the Fasciola genus, the main consequence of the high level of diversity is the frequent probability of development of resistance to anthelmintics and fast adaptation to climatic changes. In the Paragonimus genus, diversity can enhance different forms of pathogenicity, can also be related to the species of intermediate hosts, and to the definitive host. The strain of flukes plays a part in the visceral localization of P. westermani adults.

Liver Flukes: the Malady Neglected

Energy Technology Data Exchange (ETDEWEB)

Lim, Jae Hoon [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2011-06-15

Liver fluke disease is a chronic parasitic inflammatory disease of the bile ducts. Infection occurs through ingestion of fluke-infested, fresh-water raw fish. The most well-known species that cause human infection are Clonorchis sinensis, Opisthorchis viverrini and Opisthorchis felineus. Adult flukes settle in the small intrahepatic bile ducts and then they live there for 20-30 years. The long-lived flukes cause long-lasting chronic inflammation of the bile ducts and this produces epithelial hyperplasia, periductal fibrosis and bile duct dilatation. The vast majority of patients are asymptomatic, but the patients with heavy infection suffer from lassitude and nonspecific abdominal complaints. The complications are stone formation, recurrent pyogenic cholangitis and cholangiocarcinoma. Approximately 35 million people are infected with liver flukes throughout the world and the exceptionally high incidence of cholangiocarcinoma in some endemic areas is closely related with a high prevalence of liver fluke infection. Considering the impact of this food-borne malady on public health and the severe possible clinical consequences, liver fluke infection should not be forgotten or neglected.

Liver Flukes: the Malady Neglected

International Nuclear Information System (INIS)

Lim, Jae Hoon

2011-01-01

Liver fluke disease is a chronic parasitic inflammatory disease of the bile ducts. Infection occurs through ingestion of fluke-infested, fresh-water raw fish. The most well-known species that cause human infection are Clonorchis sinensis, Opisthorchis viverrini and Opisthorchis felineus. Adult flukes settle in the small intrahepatic bile ducts and then they live there for 20-30 years. The long-lived flukes cause long-lasting chronic inflammation of the bile ducts and this produces epithelial hyperplasia, periductal fibrosis and bile duct dilatation. The vast majority of patients are asymptomatic, but the patients with heavy infection suffer from lassitude and nonspecific abdominal complaints. The complications are stone formation, recurrent pyogenic cholangitis and cholangiocarcinoma. Approximately 35 million people are infected with liver flukes throughout the world and the exceptionally high incidence of cholangiocarcinoma in some endemic areas is closely related with a high prevalence of liver fluke infection. Considering the impact of this food-borne malady on public health and the severe possible clinical consequences, liver fluke infection should not be forgotten or neglected.

Endogenous growth factor stimulation of hemocyte proliferation induces resistance to Schistosoma mansoni challenge in the snail host.

Science.gov (United States)

Pila, Emmanuel A; Gordy, Michelle A; Phillips, Valerie K; Kabore, Alethe L; Rudko, Sydney P; Hanington, Patrick C

2016-05-10

Digenean trematodes are a large, complex group of parasitic flatworms that infect an incredible diversity of organisms, including humans. Larval development of most digeneans takes place within a snail (Gastropoda). Compatibility between snails and digeneans is often very specific, such that suitable snail hosts define the geographical ranges of diseases caused by these worms. The immune cells (hemocytes) of a snail are sentinels that act as a crucial barrier to infection by larval digeneans. Hemocytes coordinate a robust and specific immunological response, participating directly in parasite killing by encapsulating and clearing the infection. Hemocyte proliferation and differentiation are influenced by unknown digenean-specific exogenous factors. However, we know nothing about the endogenous control of hemocyte development in any gastropod model. Here, we identify and functionally characterize a progranulin [Biomphalaria glabrata granulin (BgGRN)] from the snail B. glabrata, a natural host for the human blood fluke Schistosoma mansoni Granulins are growth factors that drive proliferation of immune cells in organisms, spanning the animal kingdom. We demonstrate that BgGRN induces proliferation of B. glabrata hemocytes, and specifically drives the production of an adherent hemocyte subset that participates centrally in the anti-digenean defense response. Additionally, we demonstrate that susceptible B. glabrata snails can be made resistant to infection with S. mansoni by first inducing hemocyte proliferation with BgGRN. This marks the functional characterization of an endogenous growth factor of a gastropod mollusc, and provides direct evidence of gain of resistance in a snail-digenean infection model using a defined factor to induce snail resistance to infection.

Renal trematode infection due to Paratanaisia bragai in zoo housed Columbiformes and a red bird-of-paradise (Paradisaea rubra).

Science.gov (United States)

Unwin, Steve; Chantrey, Julian; Chatterton, James; Aldhoun, Jitka A; Littlewood, D Timothy J

2013-12-01

Trematode infections affect a diverse range of avian species and the organs that are parasitised are also very varied. The family Eucotylidae contains seven genera of renal flukes that parasitise various birds. In birds, mild to severe lesions have been reported for species of the genus Paratanaisia, which was originally described from columbiform and galliform specimens collected in South America and has been identified in a number of wild avian species. This paper investigates eight cases of renal trematode infection at Chester Zoo in the UK due to Paratanaisia bragai in five previously unreported species: red bird-of-paradise, Socorro dove, Mindanao bleeding heart dove, laughing dove and emerald dove. Pathological changes, which varied between species, are discussed. A known intermediate snail host Allopeas clavulinum was present in the enclosures but there was no direct evidence of trematode infection. The size of the snails, possible low prevalence and the difficulty of visualising sporocysts contributed to this. Thus the development and application of further molecular diagnostic markers that can be applied to snail tissues is warranted. Parasite identification was confirmed utilizing DNA amplification from formalin-fixed paraffin-embedded tissues using PCR and trematode specific primers. Sequencing full ssrDNA and D1-D3 lsrDNA confirmed the identity in all cases as P. bragai. However, the short 310 bp fragment used provides insufficient variation or sequence length for wider application. The epidemiology, pathology and consequences for the management of these endangered species are discussed. Preliminary work on developing an effective ante mortem diagnostic PCR test kit is also highlighted.

Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China.

Science.gov (United States)

Li, Kang; Clausen, Jesper Hedegaard; Murrell, K Darwin; Liu, Liping; Dalsgaard, Anders

2013-11-15

Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1.5%) of trematode infections (Heterophyidae and Echinostomatidae). Integrated systems using animal manure and latrine wastes as fertilizer did not show a higher prevalence of FZT. Because it was not clear whether the low risk of infection was attributable to existing effective pond management practices or a low risk of spillover of FZT from area sylvatic reservoir hosts, a survey of local wild-caught fish was conducted. Five species of FZT were discovered from a total of 271 wild-caught fish and a mean infection density of 4.0 metacercariae/100g; FZT discovered included intestinal flukes (Haplorchis spp., Procerovum varium, and Metagonimus spp.) and metacercariae tentatively identified as Clonorchis sinenesis. The common occurrence of FZT in wild-caught fish suggests that the presence of FZT in local wild animal reservoirs is substantial, and that although the current aquaculture management systems for tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level. Copyright © 2013 Elsevier B.V. All rights reserved.

Renal trematode infection due to Paratanaisia bragai in zoo housed Columbiformes and a red bird-of-paradise (Paradisaea rubra)☆

Science.gov (United States)

Unwin, Steve; Chantrey, Julian; Chatterton, James; Aldhoun, Jitka A.; Littlewood, D. Timothy J.

2012-01-01

Trematode infections affect a diverse range of avian species and the organs that are parasitised are also very varied. The family Eucotylidae contains seven genera of renal flukes that parasitise various birds. In birds, mild to severe lesions have been reported for species of the genus Paratanaisia, which was originally described from columbiform and galliform specimens collected in South America and has been identified in a number of wild avian species. This paper investigates eight cases of renal trematode infection at Chester Zoo in the UK due to Paratanaisia bragai in five previously unreported species: red bird-of-paradise, Socorro dove, Mindanao bleeding heart dove, laughing dove and emerald dove. Pathological changes, which varied between species, are discussed. A known intermediate snail host Allopeas clavulinum was present in the enclosures but there was no direct evidence of trematode infection. The size of the snails, possible low prevalence and the difficulty of visualising sporocysts contributed to this. Thus the development and application of further molecular diagnostic markers that can be applied to snail tissues is warranted. Parasite identification was confirmed utilizing DNA amplification from formalin-fixed paraffin-embedded tissues using PCR and trematode specific primers. Sequencing full ssrDNA and D1-D3 lsrDNA confirmed the identity in all cases as P. bragai. However, the short 310 bp fragment used provides insufficient variation or sequence length for wider application. The epidemiology, pathology and consequences for the management of these endangered species are discussed. Preliminary work on developing an effective ante mortem diagnostic PCR test kit is also highlighted. PMID:24533313

A Portrait of the Transcriptome of the Neglected Trematode, Fasciola gigantica—Biological and Biotechnological Implications

Science.gov (United States)

Young, Neil D.; Jex, Aaron R.; Cantacessi, Cinzia; Hall, Ross S.; Campbell, Bronwyn E.; Spithill, Terence W.; Tangkawattana, Sirikachorn; Tangkawattana, Prasarn; Laha, Thewarach; Gasser, Robin B.

2011-01-01

Fasciola gigantica (Digenea) is an important foodborne trematode that causes liver fluke disease (fascioliasis) in mammals, including ungulates and humans, mainly in tropical climatic zones of the world. Despite its socioeconomic impact, almost nothing is known about the molecular biology of this parasite, its interplay with its hosts, and the pathogenesis of fascioliasis. Modern genomic technologies now provide unique opportunities to rapidly tackle these exciting areas. The present study reports the first transcriptome representing the adult stage of F. gigantica (of bovid origin), defined using a massively parallel sequencing-coupled bioinformatic approach. From >20 million raw sequence reads, >30,000 contiguous sequences were assembled, of which most were novel. Relative levels of transcription were determined for individual molecules, which were also characterized (at the inferred amino acid level) based on homology, gene ontology, and/or pathway mapping. Comparisons of the transcriptome of F. gigantica with those of other trematodes, including F. hepatica, revealed similarities in transcription for molecules inferred to have key roles in parasite-host interactions. Overall, the present dataset should provide a solid foundation for future fundamental genomic, proteomic, and metabolomic explorations of F. gigantica, as well as a basis for applied outcomes such as the development of novel methods of intervention against this neglected parasite. PMID:21408104

A portrait of the transcriptome of the neglected trematode, Fasciola gigantica--biological and biotechnological implications.

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Neil D Young

Full Text Available Fasciola gigantica (Digenea is an important foodborne trematode that causes liver fluke disease (fascioliasis in mammals, including ungulates and humans, mainly in tropical climatic zones of the world. Despite its socioeconomic impact, almost nothing is known about the molecular biology of this parasite, its interplay with its hosts, and the pathogenesis of fascioliasis. Modern genomic technologies now provide unique opportunities to rapidly tackle these exciting areas. The present study reports the first transcriptome representing the adult stage of F. gigantica (of bovid origin, defined using a massively parallel sequencing-coupled bioinformatic approach. From >20 million raw sequence reads, >30,000 contiguous sequences were assembled, of which most were novel. Relative levels of transcription were determined for individual molecules, which were also characterized (at the inferred amino acid level based on homology, gene ontology, and/or pathway mapping. Comparisons of the transcriptome of F. gigantica with those of other trematodes, including F. hepatica, revealed similarities in transcription for molecules inferred to have key roles in parasite-host interactions. Overall, the present dataset should provide a solid foundation for future fundamental genomic, proteomic, and metabolomic explorations of F. gigantica, as well as a basis for applied outcomes such as the development of novel methods of intervention against this neglected parasite.

Disseminated peritoneal Schistosoma japonicum: a case report and review of the pathological manifestations of the helminth

International Nuclear Information System (INIS)

AlWaheeb, Salah; AlMurshed, Maryam; Dashti, Fareed; Hira Parsotam R; AlSarrafd, Lamia

2007-01-01

Schistosomiasis (also known as bilharzia, bilharziasis, bilharziosis or snail fever) is a human disease syndrome caused by infection from one of several species of parasitic trematodes of the genus Schistosoma. The three main species infecting humans are S haematobium, S japonicum, and S mansoni. S japonicum is most common in the far east, mostly in China and the Philippines. We present an unusual case of S japonicum in a 32-year-old Filipino woman who had schistosomal ova studding the peritoneal cavity and forming a mass in the right iliac fossa. (author)

Range size patterns in European freshwater trematodes

DEFF Research Database (Denmark)

Thieltges, David; Hof, Christian; Borregaard, Michael Krabbe

2011-01-01

biogeographical regions in Europe from the Limnofauna Europaea and used multiple regression analyses to test for correlations between the diversity of definitive (vertebrates) or first intermediate (gastropods) hosts and that of trematodes, and for latitudinal gradients in trematode diversity. In particular, we...... faunas. Results Latitude or first intermediate host richness had no effect on trematode richness, but definitive host richness was a strong predictor of trematode richness, among both allogenic and autogenic parasites. We found that beta diversity of trematode faunas within latitudinal bands decreased...... to the north, with similar values for allogenic and autogenic trematodes. Finally, we observed an increasing proportion of autogenic species toward the north of Europe. Main conclusions The richness of definitive hosts appears to be the driver of trematode diversity at a continental scale. The latitudinal...

Structural Basis for Inhibition of Cathepsin B Drug Target from the Human Blood Fluke, Schistosoma mansoni

Czech Academy of Sciences Publication Activity Database

Jílková, Adéla; Řezáčová, Pavlína; Lepšík, Martin; Horn, Martin; Váchová, Jana; Fanfrlík, Jindřich; Brynda, Jiří; McKerrow, J. H.; Caffrey, C. R.; Mareš, Michael

2011-01-01

Roč. 286, č. 41 (2011), s. 35770-35881 ISSN 0021-9258 R&D Projects: GA ČR GA203/09/1585; GA ČR GAP208/11/0295; GA MŠk OC09007 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50520514 Keywords : cathepsin B * schistosoma * crystal structure Subject RIV: CC - Organic Chemistry Impact factor: 4.773, year: 2011

Functional Analysis of the Unique Cytochrome P450 of the Liver Fluke Opisthorchis felineus.

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Mariya Y Pakharukova

2015-12-01

Full Text Available The basic metabolic cytochrome P450 (CYP system is essential for biotransformation of sterols and xenobiotics including drugs, for synthesis and degradation of signaling molecules in all living organisms. Most eukaryotes including free-living flatworms have numerous paralogues of the CYP gene encoding heme monooxygenases with specific substrate range. Notably, by contrast, the parasitic flatworms have only one CYP gene. The role of this enzyme in the physiology and biochemistry of helminths is not known. The flukes and tapeworms are the etiologic agents of major neglected tropical diseases of humanity. Three helminth infections (Opisthorchis viverrini, Clonorchis sinensis and Schistosoma haematobium are considered by the International Agency for Research on Cancer (IARC as definite causes of cancer. We focused our research on the human liver fluke Opisthorchis felineus, an emerging source of biliary tract disease including bile duct cancer in Russia and central Europe. The aims of this study were (i to determine the significance of the CYP activity for the morphology and survival of the liver fluke, (ii to assess CYP ability to metabolize xenobiotics, and (iii to localize the CYP activity in O. felineus tissues. We observed high constitutive expression of CYP mRNA (Real-time PCR in O. felineus. This enzyme metabolized xenobiotics selective for mammalian CYP2E1, CYP2B, CYP3A, but not CYP1A, as determined by liquid chromatography and imaging analyses. Tissue localization studies revealed the CYP activity in excretory channels, while suppression of CYP mRNA by RNA interference was accompanied by morphological changes of the excretory system and increased mortality rates of the worms. These results suggest that the CYP function is linked to worm metabolism and detoxification. The findings also suggest that the CYP enzyme is involved in vitally important processes in the organism of parasites and is a potential drug target.

Experimental Evaluation of the Pathogenicity of Different Strains of Schistosoma mansoni

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Antônio Aurélio Euzébio

2012-01-01

Full Text Available The pathogenesis of three different Schistosoma mansoni strains from the Brazilian states of Minas Gerais (BH strain and São Paulo (SJ and SD strains was evaluated in experimentally infected mice. Observations of the most severe clinical cases among local patients treated (SD strain in the city of Campinas (São Paulo, Brazil formed the basis of this study. Mice were used as definitive hosts and were infected with cercariae from Biomphalaria tenagophila (SJ and SD strains and Biomphalaria glabrata (BH strains. The parameters analyzed were as follows: number of S. mansoni eggs in mice feces; number of granulomas per tissue area in liver, spleen, lungs, pancreas, and ascending colon; measurements of hepatic and intestinal granulomas; number of adult worms; and measurements of trematode eggs. The comparison among the three strains indicated that the SD strain, isolated in Campinas, presented a higher worm recovery relative to the number of penetrating cercariae. In addition, when compared to the SJ and BH strains, the SD strain demonstrated similar pathogenicity to the BH strain, with a greater quantity of granulomas in the viscera, as well as larger granulomas and eggs. Furthermore, a greater quantity of trematode eggs was also shed in the feces.

Molecular changes in Opisthorchis viverrini (Southeast Asian liver fluke during the transition from the juvenile to the adult stage.

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Aaron R Jex

Full Text Available BACKGROUND: The Southeast Asian liver fluke (Opisthorchis viverrini chronically infects and affects tens of millions of people in regions of Asia, leading to chronic illness and, importantly, inducing malignant cancer (= cholangiocarcinoma. In spite of this, little is known, at the molecular level, about the parasite itself, its interplay with its hosts or the mechanisms of disease and/or carcinogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Here, we generated extensive RNA-Seq data (Illumina representing adult and juvenile stages of O. viverrini, and combined these sequences with previously published transcriptomic data (454 technology for this species, yielding a combined assembly of significantly increased quality and allowing quantitative assessment of transcription in the juvenile and adult stage. CONCLUSIONS: This enhanced assembly reveals that, despite the substantial biological similarities between the human liver flukes, O. viverinni and Clonorchis sinensis, there are previously unrecognized differences in major aspects of their molecular biology. Most notable are differences among the C13 and cathepsin L-like cysteine peptidases, which play key roles in tissue migration, immune evasion and feeding, and, thus, represent potential drug and/or vaccine targets. Furthermore, these data indicate that major lineages of cysteine peptidases of socioeconomically important trematodes have evolved through a process of gene loss rather than independent radiation, contrasting previous proposals.

Susceptibility of Biomphalaria tenagophila and Biomphalaria straminea to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

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JANNOTTI-PASSOS Liana Konovaloff

2000-01-01

Full Text Available In order to determine Schistosoma mansoni infection rates in Biomphalaria tenagophila and B. straminea, low stringency polymerase chain reaction (LS-PCR technique was used as a complementary method to light exposure technique. LS-PCR has already been standardized in our laboratory to detect the trematode DNA in B. glabrata. Higher S. mansoni infection rates were detected using conventional method and LS-PCR. The parasite DNA profile was detected in both species after 7-day exposure to miracidia, using LS-PCR. This technique enables early detection of schistosomiasis transmission focuses, in endemic areas, before the beginning of cercariae shedding.

Prevalence of liver flukes infections and hydatidosis in slaughtered sheep and goats in Nishapour, Khorasan Razavi, Iran

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Majid Aminzare

2018-02-01

Full Text Available Background: Food-borne trematode infections and hydatidosis are endemic diseases caused by helminths in Iran that are responsible for great economic loss and getting public health at risk. Aim: Aim of this study was to determine the prevalence of fasciolosis, dicrocoeliasis, and hydatidosis infections in slaughtered sheep and goats in Nishapour, Khorasan Razavi province of Iran. Materials and Methods: A survey was implemented on 130,107 sheep and goats slaughtered at an abattoir in Nishapour (Neyshbur city, north central Khorasan Razavi Province, Iran, to determine the prevalence of fascioliasis, dicrocoeliosis and presence of hydatidosis. Results: During a 1-year period of study, among 130,107 of sheep and goats slaughtered at Nishapour abattoir, 1064 and 7124 livers were condemned totally and partially, respectively. A total of 255 (0.19%, 181 (0.12 %, and 7751 (5.95% of livers were condemned due to cysts of Echinococcus granulosus, flukes of Fasciola spp., and Dicrocoelium dendriticum, respectively. Totally, 1932 (1.48% lungs were condemned due to hydatidosis. The significant seasonal pattern was seen for fasciolosis, dicrocoeliosis, and hydatidosis, statistically (p<0.01. Conclusion: According to this study, it seems that Neyshabour is considered as an endemic region for Fasciola spp. and D. dendriticum infections and D. dendriticum is the most widespread liver fluke found in sheep and goats.

Surface topography of two trematodes parasites infecting grey heron Ardea cinerea Jouyi (Aves, Ciconiiformes) in Qena, Egypt.

Science.gov (United States)

Ammar, Khalaf Nour Abd El-Wahed

2015-04-01

Apharyngostrigea ardeolina and Echinoparyphium recurvatum are two important digenean parasites that were recovered from small intestine of grey heron with an infection rate (16.2%) and (8.8%) respectively. The surface topography of two species was redescribed by both light and scanning electron microscopy. Using SEM studies showed that the body surface of two trematodes were covered by contact receptors, several types of sensory tegumental papillae which may have useful function in orientation and feeding through increasing the surface area of absorption, could also play a role in sensation or in selection of the materials for ingestion by the fluke. The head collar of E. recurvatum is reniform in shape, bearing uninterrupted double row of 41 collar finger-like spines, a total including 4 end group ones on both ventral corners., tegumental spines were tongue-shaped without a terminal tip.

Effect of schistosoma infection on malaria immune response: A systematic review.

Science.gov (United States)

Yesuf, Elias Ali; Dejene, Tariku

2011-01-01

Background Worldwide an estimated 225 million cases and about 800, 000 deaths due to malaria were documented in 2009. Malaria vaccines have been developed as a malaria control strategy. Immune response to these vaccines might be affected by the blood fluke schistosoma which is often co-endemic with malaria in Sub-Saharan Africa where most of phase II and Phase III malaria vaccine trials were conducted.Objectives To systematically search, appraise and synthesize the best available evidence on the effect of schistosoma infection on the immune response to malaria antigens and provide direction to future malaria vaccination trials.Types of participants The review considered studies with above 5 year old individuals as participants.Phenomenon of interest The phenomenon of interest was the presence of schistosoma infectionTypes of outcomes Blood serum levels of Th1 and Th2 specific to Merozoite Surface Proteins 1, 2, and 3 of malaria were considered as primary outcomes. While blood serum levels of IgG1, IgG2, IgG3, IFN-γ, IL-10 and TGF-β directed against Merozoite Surface Proteins were considered as secondary outcomes.Types of studies Studies with any quantitative study designs were considered for inclusion.Search Strategy Any quantitative English language articles published between 1994 and April 2011 were sought using a comprehensive search strategy.Assessment of methodological quality It was done using Joanna Briggs Institutes' Meta Analysis of Statistical Assessment and Review Instrument critical appraisal tools.Data extraction Data extraction was carried out using the Joanna Briggs Institute Meta Analysis of Statistical Assessment and Review Instrument data extraction tool.Data synthesis Meta- analysis was conducted using random effects model with an inverse variance method with RevMan5 software. Heterogeneity between the studies was assessed using ξ test at a p-value of SMD (95% CI), 0.15 (-2.00, 2.31), p=0.89.Similarly a small and statistically not significant

Molecular phylogenetic identification of Fasciola flukes in Nepal.

Science.gov (United States)

Shoriki, Takuya; Ichikawa-Seki, Madoka; Devkota, Bhuminand; Rana, Hari B; Devkota, Shiva P; Humagain, Sudeep K; Itagaki, Tadashi

2014-12-01

Eighty-one Fasciola flukes collected from 8 districts in Nepal were analyzed for their species identification on the basis of their spermatogenic status and nuclear ribosomal internal transcribed spacer 1 (ITS1) and for their phylogenetic relation with Fasciola flukes from other Asian countries on the basis of the mitochondrial NADH dehydrogenase subunit 1 (nad1) gene. Sixty-one flukes (75.3%) were aspermic Fasciola sp., and 20 flukes (24.7%) were identified as Fasciola gigantica. All of the aspermic flukes displayed the Fh/Fg type in ITS1, which was predominant in aspermic Fasciola sp. from China, and most (60 flukes) displayed the Fsp-ND1-N1 haplotype in the nad1, which had an identical nucleotide sequence to the major haplotype (Fg-C2) of the aspermic flukes from China. These results suggest that aspermic Fasciola sp. was introduced into Nepal from China. Furthermore, the results of the diversity indices, neutrality indices, and median-joining network analysis with reference haplotypes from Asian countries suggest that aspermic Fasciola sp. rapidly expanded its distribution. In contrasts, F. gigantica displayed 10 nad1 haplotypes, which showed higher population diversity indices than the haplotypes of aspermic flukes, indicating that the F. gigantica population was clearly distributed in Nepal earlier than the aspermic Fasciola population. Although the F. gigantica haplotypes from Nepal formed a star-like phylogeny consisting of a main founder haplotype (Fg-ND1-N1), together with some F. gigantica haplotypes from Myanmar and Thailand, the Nepal population differed genetically from F. gigantica populations of neighboring countries as each country had distinct founder haplotype(s). Copyright © 2014 Elsevier Inc. All rights reserved.

An Atlas for Schistosoma mansoni Organs and Life-Cycle Stages Using Cell Type-Specific Markers and Confocal Microscopy

Science.gov (United States)

Cogswell, Alexis; Williams, David L.; Newmark, Phillip A.

2011-01-01

Schistosomiasis (bilharzia) is a tropical disease caused by trematode parasites (Schistosoma) that affects hundreds of millions of people in the developing world. Currently only a single drug (praziquantel) is available to treat this disease, highlighting the importance of developing new techniques to study Schistosoma. While molecular advances, including RNA interference and the availability of complete genome sequences for two Schistosoma species, will help to revolutionize studies of these animals, an array of tools for visualizing the consequences of experimental perturbations on tissue integrity and development needs to be made widely available. To this end, we screened a battery of commercially available stains, antibodies and fluorescently labeled lectins, many of which have not been described previously for analyzing schistosomes, for their ability to label various cell and tissue types in the cercarial stage of S. mansoni. This analysis uncovered more than 20 new markers that label most cercarial tissues, including the tegument, the musculature, the protonephridia, the secretory system and the nervous system. Using these markers we present a high-resolution visual depiction of cercarial anatomy. Examining the effectiveness of a subset of these markers in S. mansoni adults and miracidia, we demonstrate the value of these tools for labeling tissues in a variety of life-cycle stages. The methodologies described here will facilitate functional analyses aimed at understanding fundamental biological processes in these parasites. PMID:21408085

Unusual thiol-based redox metabolism of parasitic flukes.

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Tripathi, Timir; Suttiprapa, Sutas; Sripa, Banchob

2017-08-01

Parasitic flukes are exposed to free radicals and, to a greater extent, reactive oxygen species (ROS) during their life cycle. Despite being relentlessly exposed to ROS released by activated immune cells, these parasites can survive for many years in the host. Cellular thiol-based redox metabolism plays a crucial role in parasite survival within their hosts. Evidence shows that oxidative stress and redox homeostasis maintenance are important clinical and pathobiochemical as well as effective therapeutic principles in various diseases. The characterization of redox and antioxidant enzymes is likely to yield good target candidates for novel drugs and vaccines. The absence of active catalase in fluke parasites offers great potential for the development of chemotherapeutic agents that act by perturbing the redox equilibrium of the cell. One of the redox-sensitive enzymes, thioredoxin glutathione reductase (TGR), has been accepted as a drug target against blood fluke infections, and related clinical trials are in progress. TGR is the sole enzyme responsible for Trx and GSH reduction in parasitic flukes. The availability of helminth genomes has accelerated the research on redox metabolism of flukes; however, significant achievements have yet to be attained. The present review summarizes current knowledge on the redox and antioxidant system of the parasitic flukes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genomes and geography: genomic insights into the evolution and phylogeography of the genus Schistosoma

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Ironside Joe E

2011-07-01

Full Text Available Abstract Blood flukes within the genus Schistosoma still remain a major cause of disease in the tropics and subtropics and the study of their evolution has been an area of major debate and research. With the advent of modern molecular and genomic approaches deeper insights have been attained not only into the divergence and speciation of these worms, but also into the historic movement of these parasites from Asia into Africa, via migration and dispersal of definitive and snail intermediate hosts. This movement was subsequently followed by a radiation of Schistosoma species giving rise to the S. mansoni and S. haematobium groups, as well as the S. indicum group that reinvaded Asia. Each of these major evolutionary events has been marked by distinct changes in genomic structure evident in differences in mitochondrial gene order and nuclear chromosomal architecture between the species associated with Asia and Africa. Data from DNA sequencing, comparative molecular genomics and karyotyping are indicative of major constitutional genomic events which would have become fixed in the ancestral populations of these worms. Here we examine how modern genomic techniques may give a more in depth understanding of the evolution of schistosomes and highlight the complexity of speciation and divergence in this group.

Secreted serine protease SmSP2 of the blood fluke Schistosoma mansoni: Biochemical characterization, localization and host protein processing

Czech Academy of Sciences Publication Activity Database

Leontovyč, Adrian; Ulrychová, Lenka; O'Donoghue, A.J.; Marešová, Lucie; Vondrášek, Jiří; Caffrey, C. R.; Mareš, Michael; Horn, Martin; Dvořák, Jan

2017-01-01

Roč. 15, č. 1 (2017), s. 18 ISSN 2336-7202. [Mezioborové setkání mladých biologů, biochemiků a chemiků /17./. 30.05.2017-01.06.2017, Milovy] R&D Projects: GA MŠk LD15101; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : Schistosoma mansoni * SmSP2 Subject RIV: CE - Biochemistry

Heterophysiasis, an intestinal fluke infection of man and vertebrates transmitted by euryhaline gastropods and fish

Science.gov (United States)

Taraschewski, H.

1984-03-01

Heterophyes heterophyes, agent of human heterophyiasis in the Near East, is transmitted in marine lagoons and saline inland waters, where the euryhaline intermediate hosts are abundant. In Egypt, mullets, the predominant second intermediate hosts, are customarily consumed raw; thus man becomes infected easily. Symptoms of human infections are usually considered mild. Mullets do not seem to be affected by the metacercariae encysted in the muscles, whereas the growth of the snail host Pirenella conica was found to be enhanced due to the infestation by the trematodes. In laboratory experiments, the flukes were found to be well developed in dogs, foxes and cats, but failed to reach sexual maturity in several other potentially piscivorous mammals and birds. In nature, dogs probably serve as the major reservoir hosts. Heterophyiasis is most prevalent in the Nile Delta, a huge brackish water area which is densely populated by humans and, consequently, also by dogs and cats. In the Far East, besides Heterophyes nocens, several other heterophysids with marine or fresh-water life-cycles are known to infect humans.

IMPORTANT: Fluke is recalling Digital Clamp Meters

CERN Multimedia

2013-01-01

Fluke is voluntarily recalling four models of Digital Clamp Meters: Fluke 373, 374, 375 and 376. If you own one of these clamp meters, please stop using it and send it back to Fluke for repair even if you have not experienced problems.   Description of the problem: "The printed circuit assembly may not be properly fastened to the test lead input jack. This may result in inaccurate voltage readings, including a low or no-voltage reading on a circuit energised with a hazardous voltage, presenting a shock, electrocution or thermal burn hazard." To determine if your clamp meter is affected by this recall notice, and for more information, click here.

Schistosome syntenin partially protects vaccinated mice against Schistosoma mansoni infection.

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Barbara C Figueiredo

2014-08-01

Full Text Available Schistosomiasis is a neglected tropical disease caused by several species of trematode of the genus Schistosoma. The disease affects more than 200 million people in the world and causes up to 280,000 deaths per year, besides having high morbidity due to chronic illness that damages internal organs. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control disease is a combination of drug treatment and immunization with an anti-schistosome vaccine. Among the most promising molecules as vaccine candidates are the proteins present in the tegument and digestive tract of the parasite.In this study, we describe for the first time Schistosoma mansoni syntenin (SmSynt and we evaluate its potential as a recombinant vaccine. We demonstrate by real-time PCR that syntenin is mainly expressed in intravascular life stages (schistosomula and adult worms of the parasite life cycle and, by confocal microscopy, we localize it in digestive epithelia in adult worms and schistosomula. Administration of siRNAs targeting SmSynt leads to the knock-down of syntenin gene and protein levels, but this has no demonstrable impact on parasite morphology or viability, suggesting that high SmSynt gene expression is not essential for the parasites in vitro. Mice immunization with rSmSynt, formulated with Freund's adjuvant, induces a Th1-type response, as suggested by the production of IFN-γ and TNF-α by rSmSynt-stimulated cultured splenocytes. The protective effect conferred by vaccination with rSmSynt was demonstrated by 30-37% reduction of worm burden, 38-43% reduction in the number, and 35-37% reduction in the area, of liver granulomas.Our report is the first characterization of syntenin in Schistosoma mansoni and our data suggest that this protein is a potential candidate for the development of a multi-antigen vaccine to control schistosomiasis.

Homology-based annotation of non-coding RNAs in the genomes of Schistosoma mansoni and Schistosoma japonicum

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Santana Clara

2009-10-01

Full Text Available Abstract Background Schistosomes are trematode parasites of the phylum Platyhelminthes. They are considered the most important of the human helminth parasites in terms of morbidity and mortality. Draft genome sequences are now available for Schistosoma mansoni and Schistosoma japonicum. Non-coding RNA (ncRNA plays a crucial role in gene expression regulation, cellular function and defense, homeostasis, and pathogenesis. The genome-wide annotation of ncRNAs is a non-trivial task unless well-annotated genomes of closely related species are already available. Results A homology search for structured ncRNA in the genome of S. mansoni resulted in 23 types of ncRNAs with conserved primary and secondary structure. Among these, we identified rRNA, snRNA, SL RNA, SRP, tRNAs and RNase P, and also possibly MRP and 7SK RNAs. In addition, we confirmed five miRNAs that have recently been reported in S. japonicum and found two additional homologs of known miRNAs. The tRNA complement of S. mansoni is comparable to that of the free-living planarian Schmidtea mediterranea, although for some amino acids differences of more than a factor of two are observed: Leu, Ser, and His are overrepresented, while Cys, Meth, and Ile are underrepresented in S. mansoni. On the other hand, the number of tRNAs in the genome of S. japonicum is reduced by more than a factor of four. Both schistosomes have a complete set of minor spliceosomal snRNAs. Several ncRNAs that are expected to exist in the S. mansoni genome were not found, among them the telomerase RNA, vault RNAs, and Y RNAs. Conclusion The ncRNA sequences and structures presented here represent the most complete dataset of ncRNA from any lophotrochozoan reported so far. This data set provides an important reference for further analysis of the genomes of schistosomes and indeed eukaryotic genomes at large.

Genomes of Fasciola hepatica from the Americas Reveal Colonization with Neorickettsia Endobacteria Related to the Agents of Potomac Horse and Human Sennetsu Fevers

Science.gov (United States)

McNulty, Samantha N.; Rosa, Bruce A.; Fontenla, Santiago; Choi, Young-Jun; Hallsworth-Pepin, Kymberlie; Kammili, Lakshmi; Latham, Patricia S.; Dell’Oca, Nicolas; Dominguez, Fernanda; Carmona, Carlos; Fischer, Peter U.; Mitreva, Makedonka

2017-01-01

Food borne trematodes (FBTs) are an assemblage of platyhelminth parasites transmitted through the food chain, four of which are recognized as neglected tropical diseases (NTDs). Fascioliasis stands out among the other NTDs due to its broad and significant impact on both human and animal health, as Fasciola sp., are also considered major pathogens of domesticated ruminants. Here we present a reference genome sequence of the common liver fluke, Fasciola hepatica isolated from sheep, complementing previously reported isolate from cattle. A total of 14,642 genes were predicted from the 1.14 GB genome of the liver fluke. Comparative genomics indicated that F. hepatica Oregon and related food-borne trematodes are metabolically less constrained than schistosomes and cestodes, taking advantage of the richer millieux offered by the hepatobiliary organs. Protease families differentially expanded between diverse trematodes may facilitate migration and survival within the heterogeneous environments and niches within the mammalian host. Surprisingly, the sequencing of Oregon and Uruguay F. hepatica isolates led to the first discovery of an endobacteria in this species. Two contigs from the F. hepatica Oregon assembly were joined to complete the 859,205 bp genome of a novel Neorickettsia endobacterium (nFh) closely related to the etiological agents of human Sennetsu and Potomac horse fevers. Immunohistochemical studies targeting a Neorickettsia surface protein found nFh in specific organs and tissues of the adult trematode including the female reproductive tract, eggs, the Mehlis’ gland, seminal vesicle, and oral suckers, suggesting putative routes for fluke-to-fluke and fluke-to-host transmission. The genomes of F. hepatica and nFh will serve as a resource for further exploration of the biology of F. hepatica, and specifically its newly discovered trans-kingdom interaction with nFh and the impact of both species on disease in ruminants and humans. PMID:28060841

Genomes of Fasciola hepatica from the Americas Reveal Colonization with Neorickettsia Endobacteria Related to the Agents of Potomac Horse and Human Sennetsu Fevers.

Science.gov (United States)

McNulty, Samantha N; Tort, Jose F; Rinaldi, Gabriel; Fischer, Kerstin; Rosa, Bruce A; Smircich, Pablo; Fontenla, Santiago; Choi, Young-Jun; Tyagi, Rahul; Hallsworth-Pepin, Kymberlie; Mann, Victoria H; Kammili, Lakshmi; Latham, Patricia S; Dell'Oca, Nicolas; Dominguez, Fernanda; Carmona, Carlos; Fischer, Peter U; Brindley, Paul J; Mitreva, Makedonka

2017-01-01

Food borne trematodes (FBTs) are an assemblage of platyhelminth parasites transmitted through the food chain, four of which are recognized as neglected tropical diseases (NTDs). Fascioliasis stands out among the other NTDs due to its broad and significant impact on both human and animal health, as Fasciola sp., are also considered major pathogens of domesticated ruminants. Here we present a reference genome sequence of the common liver fluke, Fasciola hepatica isolated from sheep, complementing previously reported isolate from cattle. A total of 14,642 genes were predicted from the 1.14 GB genome of the liver fluke. Comparative genomics indicated that F. hepatica Oregon and related food-borne trematodes are metabolically less constrained than schistosomes and cestodes, taking advantage of the richer millieux offered by the hepatobiliary organs. Protease families differentially expanded between diverse trematodes may facilitate migration and survival within the heterogeneous environments and niches within the mammalian host. Surprisingly, the sequencing of Oregon and Uruguay F. hepatica isolates led to the first discovery of an endobacteria in this species. Two contigs from the F. hepatica Oregon assembly were joined to complete the 859,205 bp genome of a novel Neorickettsia endobacterium (nFh) closely related to the etiological agents of human Sennetsu and Potomac horse fevers. Immunohistochemical studies targeting a Neorickettsia surface protein found nFh in specific organs and tissues of the adult trematode including the female reproductive tract, eggs, the Mehlis' gland, seminal vesicle, and oral suckers, suggesting putative routes for fluke-to-fluke and fluke-to-host transmission. The genomes of F. hepatica and nFh will serve as a resource for further exploration of the biology of F. hepatica, and specifically its newly discovered trans-kingdom interaction with nFh and the impact of both species on disease in ruminants and humans.

Genomes of Fasciola hepatica from the Americas Reveal Colonization with Neorickettsia Endobacteria Related to the Agents of Potomac Horse and Human Sennetsu Fevers.

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Samantha N McNulty

2017-01-01

Full Text Available Food borne trematodes (FBTs are an assemblage of platyhelminth parasites transmitted through the food chain, four of which are recognized as neglected tropical diseases (NTDs. Fascioliasis stands out among the other NTDs due to its broad and significant impact on both human and animal health, as Fasciola sp., are also considered major pathogens of domesticated ruminants. Here we present a reference genome sequence of the common liver fluke, Fasciola hepatica isolated from sheep, complementing previously reported isolate from cattle. A total of 14,642 genes were predicted from the 1.14 GB genome of the liver fluke. Comparative genomics indicated that F. hepatica Oregon and related food-borne trematodes are metabolically less constrained than schistosomes and cestodes, taking advantage of the richer millieux offered by the hepatobiliary organs. Protease families differentially expanded between diverse trematodes may facilitate migration and survival within the heterogeneous environments and niches within the mammalian host. Surprisingly, the sequencing of Oregon and Uruguay F. hepatica isolates led to the first discovery of an endobacteria in this species. Two contigs from the F. hepatica Oregon assembly were joined to complete the 859,205 bp genome of a novel Neorickettsia endobacterium (nFh closely related to the etiological agents of human Sennetsu and Potomac horse fevers. Immunohistochemical studies targeting a Neorickettsia surface protein found nFh in specific organs and tissues of the adult trematode including the female reproductive tract, eggs, the Mehlis' gland, seminal vesicle, and oral suckers, suggesting putative routes for fluke-to-fluke and fluke-to-host transmission. The genomes of F. hepatica and nFh will serve as a resource for further exploration of the biology of F. hepatica, and specifically its newly discovered trans-kingdom interaction with nFh and the impact of both species on disease in ruminants and humans.

Global status of fish-borne zoonotic trematodiasis in humans

DEFF Research Database (Denmark)

Hung, Nguyen Manh; Madsen, Henry; Fried, Bernard

2013-01-01

) are listed. Some trematodes, which are highly pathogenic for humans such as Clonorchis sinensis, Opisthorchis viverrini, O. felineus are discussed in detail, i.e. infection status in humans in endemic areas, clinical aspects, symptoms and pathology of disease caused by these flukes. Other liver fluke species...

The small RNA complement of adult Schistosoma haematobium.

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Andreas J Stroehlein

2018-05-01

Full Text Available Blood flukes of the genus Schistosoma cause schistosomiasis-a neglected tropical disease (NTD that affects more than 200 million people worldwide. Studies of schistosome genomes have improved our understanding of the molecular biology of flatworms, but most of them have focused largely on protein-coding genes. Small non-coding RNAs (sncRNAs have been explored in selected schistosome species and are suggested to play essential roles in the post-transcriptional regulation of genes, and in modulating flatworm-host interactions. However, genome-wide small RNA data are currently lacking for key schistosomes including Schistosoma haematobium-the causative agent of urogenital schistosomiasis of humans.MicroRNAs (miRNAs and other sncRNAs of male and female adults of S. haematobium and small RNA transcription levels were explored by deep sequencing, genome mapping and detailed bioinformatic analyses.In total, 89 transcribed miRNAs were identified in S. haematobium-a similar complement to those reported for the congeners S. mansoni and S. japonicum. Of these miRNAs, 34 were novel, with no homologs in other schistosomes. Most miRNAs (n = 64 exhibited sex-biased transcription, suggestive of roles in sexual differentiation, pairing of adult worms and reproductive processes. Of the sncRNAs that were not miRNAs, some related to the spliceosome (n = 21, biogenesis of other RNAs (n = 3 or ribozyme functions (n = 16, whereas most others (n = 3798 were novel ('orphans' with unknown functions.This study provides the first genome-wide sncRNA resource for S. haematobium, extending earlier studies of schistosomes. The present work should facilitate the future curation and experimental validation of sncRNA functions in schistosomes to enhance our understanding of post-transcriptional gene regulation and of the roles that sncRNAs play in schistosome reproduction, development and parasite-host cross-talk.

The small RNA complement of adult Schistosoma haematobium.

Science.gov (United States)

Stroehlein, Andreas J; Young, Neil D; Korhonen, Pasi K; Hall, Ross S; Jex, Aaron R; Webster, Bonnie L; Rollinson, David; Brindley, Paul J; Gasser, Robin B

2018-05-01

Blood flukes of the genus Schistosoma cause schistosomiasis-a neglected tropical disease (NTD) that affects more than 200 million people worldwide. Studies of schistosome genomes have improved our understanding of the molecular biology of flatworms, but most of them have focused largely on protein-coding genes. Small non-coding RNAs (sncRNAs) have been explored in selected schistosome species and are suggested to play essential roles in the post-transcriptional regulation of genes, and in modulating flatworm-host interactions. However, genome-wide small RNA data are currently lacking for key schistosomes including Schistosoma haematobium-the causative agent of urogenital schistosomiasis of humans. MicroRNAs (miRNAs) and other sncRNAs of male and female adults of S. haematobium and small RNA transcription levels were explored by deep sequencing, genome mapping and detailed bioinformatic analyses. In total, 89 transcribed miRNAs were identified in S. haematobium-a similar complement to those reported for the congeners S. mansoni and S. japonicum. Of these miRNAs, 34 were novel, with no homologs in other schistosomes. Most miRNAs (n = 64) exhibited sex-biased transcription, suggestive of roles in sexual differentiation, pairing of adult worms and reproductive processes. Of the sncRNAs that were not miRNAs, some related to the spliceosome (n = 21), biogenesis of other RNAs (n = 3) or ribozyme functions (n = 16), whereas most others (n = 3798) were novel ('orphans') with unknown functions. This study provides the first genome-wide sncRNA resource for S. haematobium, extending earlier studies of schistosomes. The present work should facilitate the future curation and experimental validation of sncRNA functions in schistosomes to enhance our understanding of post-transcriptional gene regulation and of the roles that sncRNAs play in schistosome reproduction, development and parasite-host cross-talk.

Fascioliasis: An Ongoing Zoonotic Trematode Infection

OpenAIRE

Nyindo, Mramba; Lukambagire, Abdul-Hamid

2015-01-01

Zoonotic trematode infections are an area of the neglected tropical diseases that have become of major interest to global and public health due to their associated morbidity. Human fascioliasis is a trematode zoonosis of interest in public health. It affects approximately 50 million people worldwide and over 180 million are at risk of infection in both developed and underdeveloped countries. The one health paradigm is an area that seeks to address the problem of zoonotic infections through a ...

Taxonomy Icon Data: Schistosoma japonicum [Taxonomy Icon

Lifescience Database Archive (English)

Full Text Available Schistosoma japonicum Schistosoma japonicum Platyhelminthes Schistosoma_japonicum_L.png Schistoso...ma_japonicum_NL.png Schistosoma_japonicum_S.png Schistosoma_japonicum_NS.png http://bioscience...dbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonicum&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistoso...ma+japonicum&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistoso...ma+japonicum&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonicum&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=132 ...

Agrochemicals increase trematode infections in a declining amphibian species.

Science.gov (United States)

Rohr, Jason R; Schotthoefer, Anna M; Raffel, Thomas R; Carrick, Hunter J; Halstead, Neal; Hoverman, Jason T; Johnson, Catherine M; Johnson, Lucinda B; Lieske, Camilla; Piwoni, Marvin D; Schoff, Patrick K; Beasley, Val R

2008-10-30

Global amphibian declines have often been attributed to disease, but ignorance of the relative importance and mode of action of potential drivers of infection has made it difficult to develop effective remediation. In a field study, here we show that the widely used herbicide, atrazine, was the best predictor (out of more than 240 plausible candidates) of the abundance of larval trematodes (parasitic flatworms) in the declining northern leopard frog Rana pipiens. The effects of atrazine were consistent across trematode taxa. The combination of atrazine and phosphate--principal agrochemicals in global corn and sorghum production--accounted for 74% of the variation in the abundance of these often debilitating larval trematodes (atrazine alone accounted for 51%). Analysis of field data supported a causal mechanism whereby both agrochemicals increase exposure and susceptibility to larval trematodes by augmenting snail intermediate hosts and suppressing amphibian immunity. A mesocosm experiment demonstrated that, relative to control tanks, atrazine tanks had immunosuppressed tadpoles, had significantly more attached algae and snails, and had tadpoles with elevated trematode loads, further supporting a causal relationship between atrazine and elevated trematode infections in amphibians. These results raise concerns about the role of atrazine and phosphate in amphibian declines, and illustrate the value of quantifying the relative importance of several possible drivers of disease risk while determining the mechanisms by which they facilitate disease emergence.

Helminths of Wild Predatory Mammals (Mammalia, Carnivora of Ukraine. Trematodes

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Korol E. N.

2016-08-01

Full Text Available The paper summarises information on 11 species of trematodes parasitic in 9 species of wild carnivorans of Ukraine. The largest number of trematode species (9 was found in the red fox (Vulpes vulpes. Alaria alata (Diplostomidae appeared to be the most common trematode parasite in the studied group; it was found in 4 host species from 9 administrative regions and Crimea.

Farm-level risk factors for fish-borne zoonotic trematode infection in integrated small-scale fish farms in northern Vietnam.

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Van Thi Phan

Full Text Available BACKGROUND: Northern Vietnam is an endemic region for fish-borne zoonotic trematodes (FZT, including liver and intestinal flukes. Humans acquire the FZT infection by eating raw or inadequately cooked fish. The production of FZT-free fish in aquaculture is a key component in establishing a sustainable program to prevent and control the FZT transmission to humans. Interventions in aquaculture should be based on knowledge of the main risk factors associated with FZT transmission. METHODOLOGY/PRINCIPAL FINDINGS: A longitudinal study was carried out from June 2006 to May 2007 in Nam Dinh province, Red River Delta to investigate the development and risk factors of FZT infections in freshwater cultured fish. A total of 3820 fish were sampled six times at two-month intervals from 96 fish farms. Logistic analysis with repeated measurements was used to evaluate potential risk factors based on information collected through questionnaire interviews with 61 fish farm owners. The results showed that the FZT infections significantly increased from first sampling in June to July 2006 (65% to sixth sampling in April to May, 2007 (76%. The liver fluke, Clonorchis sinensis and different zoonotic intestinal flukes including Haplochis pumilio, H. taichui, H. yokogawai, Centrocestus formosanus and Procerovum varium were found in sampled fish. Duration of fish cultured (sampling times, mebendazole drug self-medication of household members, presence of snails in the pond, and feeding fish with green vegetation collected outside fish farms all had a significant effect on the development of FZT prevalence in the fish. CONCLUSIONS/SIGNIFICANCE: The FZT prevalence in fish increased by 11 percentage points during a one-year culture period and the risk factors for the development of infection were identified. Results also highlight that the young fish are already highly infected when stocked into the grow-out systems. This knowledge should be incorporated into control

Three-dimensional structure of a schistosome serpin revealing an unusual configuration of the helical subdomain

Energy Technology Data Exchange (ETDEWEB)

Granzin, Joachim [Institute of Complex Systems, ICS-6: Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich (Germany); Huang, Ying; Topbas, Celalettin [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Huang, Wenying [Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Wu, Zhiping [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Misra, Saurav [Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Hazen, Stanley L. [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Blanton, Ronald E. [Department of Infectious Diseases, Case Western Reserve University, Cleveland, OH 44190 (United States); Lee, Xavier [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Weiergräber, Oliver H., E-mail: o.h.weiergraeber@fz-juelich.de [Institute of Complex Systems, ICS-6: Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich (Germany)

2012-06-01

The crystal structure of ShSPI, a serpin from the blood fluke S. haematobium, reveals some peculiar features of the helical subdomain which have not been observed previously in the serpin superfamily. Parasitic organisms are constantly challenged by the defence mechanisms of their respective hosts, which often depend on serine protease activities. Consequently, protease inhibitors such as those belonging to the serpin superfamily have emerged as protective elements that support the survival of the parasites. This report describes the crystal structure of ShSPI, a serpin from the trematode Schistosoma haematobium. The protein is exposed on the surface of invading cercaria as well as of adult worms, suggesting its involvement in the parasite–host interaction. While generally conforming to the well established serpin fold, the structure reveals several distinctive features, mostly concerning the helical subdomain of the protein. It is proposed that these peculiarities are related to the unique biological properties of a small serpin subfamily which is conserved among pathogenic schistosomes.

Random and systematic sampling error when hooking fish to monitor skin fluke (Benedenia seriolae) and gill fluke (Zeuxapta seriolae) burden in Australian farmed yellowtail kingfish (Seriola lalandi).

Science.gov (United States)

Fensham, J R; Bubner, E; D'Antignana, T; Landos, M; Caraguel, C G B

2018-05-01

The Australian farmed yellowtail kingfish (Seriola lalandi, YTK) industry monitor skin fluke (Benedenia seriolae) and gill fluke (Zeuxapta seriolae) burden by pooling the fluke count of 10 hooked YTK. The random and systematic error of this sampling strategy was evaluated to assess potential impact on treatment decisions. Fluke abundance (fluke count per fish) in a study cage (estimated 30,502 fish) was assessed five times using the current sampling protocol and its repeatability was estimated the repeatability coefficient (CR) and the coefficient of variation (CV). Individual body weight, fork length, fluke abundance, prevalence, intensity (fluke count per infested fish) and density (fluke count per Kg of fish) were compared between 100 hooked and 100 seined YTK (assumed representative of the entire population) to estimate potential selection bias. Depending on the fluke species and age category, CR (expected difference in parasite count between 2 sampling iterations) ranged from 0.78 to 114 flukes per fish. Capturing YTK by hooking increased the selection of fish of a weight and length in the lowest 5th percentile of the cage (RR = 5.75, 95% CI: 2.06-16.03, P-value = 0.0001). These lower end YTK had on average an extra 31 juveniles and 6 adults Z. seriolae per Kg of fish and an extra 3 juvenile and 0.4 adult B. seriolae per Kg of fish, compared to the rest of the cage population (P-value sampling towards the smallest and most heavily infested fish in the population, resulting in poor repeatability (more variability amongst sampled fish) and an overestimation of parasite burden in the population. In this particular commercial situation these finding supported that health management program, where the finding of an underestimation of parasite burden could provide a production impact on the study population. In instances where fish populations and parasite burdens are more homogenous, sampling error may be less severe. Sampling error when capturing fish

The Schistosoma Granuloma: Friend or Foe?

Science.gov (United States)

Hams, Emily; Aviello, Gabriella; Fallon, Padraic G.

2013-01-01

Infection of man with Schistosoma species of trematode parasite causes marked chronic morbidity. Individuals that become infected with Schistosomes may develop a spectrum of pathology ranging from mild cercarial dermatitis to severe tissue inflammation, in particular within the liver and intestines, which can lead to life threatening hepatosplenomegaly. It is well established that the etiopathology during schistosomiasis is primarily due to an excessive or unregulated inflammatory response to the parasite, in particular to eggs that become trapped in various tissue. The eggs forms the foci of a classical type 2 granulomatous inflammation, characterized by an eosinophil-rich, CD4+ T helper (Th) 2 cell dominated infiltrate with additional infiltration of alternatively activated macrophages (M2). Indeed the sequela of the type 2 perioval granuloma is marked fibroblast infiltration and development of fibrosis. Paradoxically, while the granuloma is the cause of pathology it also can afford some protection, whereby the granuloma minimizes collateral tissue damage in the liver and intestines. Furthermore, the parasite is exquisitely reliant on the host to mount a granulomatous reaction to the eggs as this inflammatory response facilitates the successful excretion of the eggs from the host. In this focused review we will address the conundrum of the S. mansoni granuloma acting as both friend and foe in inflammation during infection. PMID:23596444

Proteomic analysis of human skin treated with larval schistosome peptidases reveals distinct invasion strategies among species of blood flukes.

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Jessica Ingram

2011-09-01

Full Text Available Skin invasion is the initial step in infection of the human host by schistosome blood flukes. Schistosome larvae have the remarkable ability to overcome the physical and biochemical barriers present in skin in the absence of any mechanical trauma. While a serine peptidase with activity against insoluble elastin appears to be essential for this process in one species of schistosomes, Schistosoma mansoni, it is unknown whether other schistosome species use the same peptidase to facilitate entry into their hosts.Recent genome sequencing projects, together with a number of biochemical studies, identified alternative peptidases that Schistosoma japonicum or Trichobilharzia regenti could use to facilitate migration through skin. In this study, we used comparative proteomic analysis of human skin treated with purified cercarial elastase, the known invasive peptidase of S. mansoni, or S. mansoni cathespin B2, a close homolog of the putative invasive peptidase of S. japonicum, to identify substrates of either peptidase. Select skin proteins were then confirmed as substrates by in vitro digestion assays.This study demonstrates that an S. mansoni ortholog of the candidate invasive peptidase of S. japonicum and T. regenti, cathepsin B2, is capable of efficiently cleaving many of the same host skin substrates as the invasive serine peptidase of S. mansoni, cercarial elastase. At the same time, identification of unique substrates and the broader species specificity of cathepsin B2 suggest that the cercarial elastase gene family amplified as an adaptation of schistosomes to human hosts.

Molecular phylogenetic analysis of Fasciola flukes from eastern India.

Science.gov (United States)

Hayashi, Kei; Ichikawa-Seki, Madoka; Mohanta, Uday Kumar; Singh, T Shantikumar; Shoriki, Takuya; Sugiyama, Hiromu; Itagaki, Tadashi

2015-10-01

Fasciola flukes from eastern India were characterized on the basis of spermatogenesis status and nuclear ITS1. Both Fasciola gigantica and aspermic Fasciola flukes were detected in Imphal, Kohima, and Gantoku districts. The sequences of mitochondrial nad1 were analyzed to infer their phylogenetical relationship with neighboring countries. The haplotypes of aspermic Fasciola flukes were identical or showed a single nucleotide substitution compared to those from populations in the neighboring countries, corroborating the previous reports that categorized them in the same lineage. However, the prevalence of aspermic Fasciola flukes in eastern India was lower than those in the neighboring countries, suggesting that they have not dispersed throughout eastern India. In contrast, F. gigantica was predominant and well diversified, and the species was thought to be distributed in the area for a longer time than the aspermic Fasciola flukes. Fasciola gigantica populations from eastern India were categorized into two distinct haplogroups A and B. The level of their genetic diversity suggests that populations belonging to haplogroup A have dispersed from the west side of the Indian subcontinent to eastern India with the artificial movement of domestic cattle, Bos indicus, whereas populations belonging to haplogroup B might have spread from Myanmar to eastern India with domestic buffaloes, Bubalus bubalis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Anti-Inflammatory Properties of Menthol and Menthone in Schistosoma mansoni Infection

Science.gov (United States)

Zaia, Mauricio G.; Cagnazzo, Túlio di Orlando; Feitosa, Karina A.; Soares, Edson G.; Faccioli, Lúcia H.; Allegretti, Silmara M.; Afonso, Ana; Anibal, Fernanda de Freitas

2016-01-01

Schistosomiasis is a parasitic disease caused by several species of trematode worms and it is believed that more than 261 million people are affected worldwide. New drug development has become essential because there is a risk of the parasite becoming resistant to Praziquantel, the only drug available for this infection. This study evaluated parasitological, immunological and histological parameters in mice infected with Schistosoma mansoni and treated with an herbal commercial medicine. This drug consists of menthol (30–55%) and menthone (14–32%). A 60 day treatment regimen with the herbal medicine decreased the number of S. mansoni eggs in the feces, liver, and intestine and reduced the number of hepatic granulomas. We observed a reduction of 84% in blood eosinophilia and a decrease in the IL-4 and IL-10 blood levels after treatment. Therefore, we propose that schistosomiasis treatment with this herbal medicine for 60 days has an immunomodulatory and anti-inflammatory action in this animal model for schistosomiasis thus contributing to the decrease in physio pathological effects caused by S. mansoni infection. PMID:27378927

The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements

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Morales Maria E

2005-02-01

Full Text Available Abstract Background Of the major families of long terminal repeat (LTR retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT, RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs

[Trematodes (Trematoda) of bats (Chiroptera) from the Middle Volga Region].

Science.gov (United States)

Kirillov, A A; Kirillova, N Iu; Vekhnik, V P

2012-01-01

The data on species diversity of trematodes from bats collected in the Middle Volga Region are summarized. According to original and literary data, 20 trematode species were recorded in bats of the region examined. Plagiorchis elegans, Lecithodendrium skrjabini, L. rysavyi, Prosthodendrium hurkovaae, and Pycnoporus megacotyle are specified for the bat fauna of Russia for the first time. For 11 species of parasites, new hosts are recorded. The analysis of bat helminthes demonstrated that the fauna of trematodes of the northern bat (12 species of trematodes), of the pond, and of the Brandt's bats is the most diverse, constituting more than 10 parasite species per bat species. The largest number of final hosts in the Middle Volga Region is characteristic of Plagiorchis koreanus and Prosthodendrium chilostomum; the latter species were revealed in 8 and 7 bat species, respectively. Trematodes of bats possess a high degree of host specificity. 17 species parasitize exclusively in bats out of 20 parasite species registered for the order Chiroptera. Only 3 species (Plagiorchis elegans, P. vespertilionis, and Prosthodendrium chilostomum) show wide degree of specificity, being found in other animals. Taxonomic position, the circle of hosts, collecting sites, and brief data in biology and geographical distribution for each helminth species are specified. Morphological descriptions and original figures for all the trematode species revealed in bats of the Middle Volga Region are given.

Host diversity and latitude drive the trematode diversity patterns in the European freshwater fauna

DEFF Research Database (Denmark)

Thieltges, David W.; Hof, Christian; Dehling, D. Matthias

2011-01-01

biogeographical regions in Europe from the Limnofauna Europaea and used multiple regression analyses to test for correlations between the diversity of definitive (vertebrates) or first intermediate (gastropods) hosts and that of trematodes, and for latitudinal gradients in trematode diversity. In particular, we...... faunas. Results Latitude or first intermediate host richness had no effect on trematode richness, but definitive host richness was a strong predictor of trematode richness, among both allogenic and autogenic parasites. We found that beta diversity of trematode faunas within latitudinal bands decreased...... to the north, with similar values for allogenic and autogenic trematodes. Finally, we observed an increasing proportion of autogenic species toward the north of Europe. Main conclusions The richness of definitive hosts appears to be the driver of trematode diversity at a continental scale. The latitudinal...

Digenetic trematodes in South American sea lions from southern Brazilian waters.

Science.gov (United States)

Pereira, E M; Müller, G; Secchi, E; Pereira, J; Valente, A L S

2013-10-01

The aim of this work was to perform a systematic study to detect and quantify the digenetic trematode infections in South American sea lions from the southern Brazilian coast. Twenty-four South American sea lions, Otaria flavescens (Carnivora: Otaridae), were found dead along the coast of Rio Grande do Sul State, Brazil, between June 2010 and September of 2011. Two trematode species were found in the intestines of O. flavescens, i.e., Stephanoprora uruguayense (Digenea: Echinostomatidae) and Ascocotyle (Phagicola) longa (Digenea: Heterophyidae). Ascocotyle (P.) longa reached a prevalence of 33.3% and mean intensity of 248,500, whereas S. uruguayense showed a prevalence of 4.2% and mean intensity of 202. The 2 trematode species infecting sea lions were likely transmitted by feeding on mullets, Mugil platanus, that commonly harbor heterophyid metacercariae. The present work is the first report of digenetic trematodes infecting O. flavescens in Brazil. The high prevalence and mean intensity values of the 2 trematode species infecting sea lions in the present study suggest caution in human consumption of mullets and other fish, which can be infected with the metacercariae of these trematodes known to have zoonotic potential.

Prevalence of trematode infection in cattle and common flukecides ...

African Journals Online (AJOL)

Furthermore, the study has shown that Albendazole, combination of Levamisole and Oxyclozanide (Nilzan plus®) and Nitroxynil (Trodax®) were the main anthelmintics used for treatment and control of trematode infections in cattle in the District. The present study has clearly shown that trematode infections were present in ...

Approaches to genotyping individual miracidia of Schistosoma japonicum.

Science.gov (United States)

Xiao, Ning; Remais, Justin V; Brindley, Paul J; Qiu, Dong-Chuan; Carlton, Elizabeth J; Li, Rong-Zhi; Lei, Yang; Blair, David

2013-12-01

Molecular genetic tools are needed to address questions as to the source and dynamics of transmission of the human blood fluke Schistosoma japonicum in regions where human infections have reemerged, and to characterize infrapopulations in individual hosts. The life stage that interests us as a target for collecting genotypic data is the miracidium, a very small larval stage that consequently yields very little DNA for analysis. Here, we report the successful development of a multiplex format permitting genotyping of 17 microsatellite loci in four sequential multiplex reactions using a single miracidium held on a Whatman Classic FTA indicating card. This approach was successful after short storage periods, but after long storage (>4 years), considerable difficulty was encountered in multiplex genotyping, necessitating the use of whole genome amplification (WGA) methods. WGA applied to cards stored for long periods of time resulted in sufficient DNA for accurate and repeatable genotyping. Trials and tests of these methods, as well as application to some field-collected samples, are reported, along with the discussion of the potential insights to be gained from such techniques. These include recognition of sibships among miracidia from a single host, and inference of the minimum number of worm pairs that might be present in a host.

Fascioliasis: An Ongoing Zoonotic Trematode Infection.

Science.gov (United States)

Nyindo, Mramba; Lukambagire, Abdul-Hamid

2015-01-01

Zoonotic trematode infections are an area of the neglected tropical diseases that have become of major interest to global and public health due to their associated morbidity. Human fascioliasis is a trematode zoonosis of interest in public health. It affects approximately 50 million people worldwide and over 180 million are at risk of infection in both developed and underdeveloped countries. The one health paradigm is an area that seeks to address the problem of zoonotic infections through a comprehensive and sustainable approach. This review attempts to address the major challenges in managing human and animal fascioliasis with valuable insights gained from the one health paradigm to global health and multidisciplinary integration.

MOLECULAR MECHANISMS THAT LEAD TO CHOLANGIOCARCINOMA, DURING CHRONIC INFECTION OF LIVER FLUKES

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A. O. Bogdanov

2015-01-01

Full Text Available Cholangiocarcinoma is a malignant tumor, characterized by poor prognosis and a low five-year survival rate. There is a clear correlation between the incidence of opisthorchiasis and high incidence of cholangiocarcinoma in South-East Asia. Liver flukes Clonorchis sinensis and Opisthorchis viverrini are I class carcinogens. There are some endemic regions of opisthorchiasis In the Russian Federation. The most important factor that leads to carcinogenesis during liver fluke infection is chronic inflammation. This review article focuses on the communication of chronic inflammation caused by invasion of liver flukes and cholangiocarcinoma. This paper summarizes the current knowledge about the risk factors for cholangiocarcinoma, as well as knowledge about the molecular aspects of the induction of carcinogenesis by liver flukes.

Fascioliasis: An Ongoing Zoonotic Trematode Infection

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Nyindo, Mramba; Lukambagire, Abdul-Hamid

2015-01-01

Zoonotic trematode infections are an area of the neglected tropical diseases that have become of major interest to global and public health due to their associated morbidity. Human fascioliasis is a trematode zoonosis of interest in public health. It affects approximately 50 million people worldwide and over 180 million are at risk of infection in both developed and underdeveloped countries. The one health paradigm is an area that seeks to address the problem of zoonotic infections through a comprehensive and sustainable approach. This review attempts to address the major challenges in managing human and animal fascioliasis with valuable insights gained from the one health paradigm to global health and multidisciplinary integration. PMID:26417603

Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake

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Soldánová, Miroslava; Georgieva, Simona; Roháčováa, Jana; Knudsen, Rune; Kuhn, Jesper A.; Henriksen, Eirik H.; Siwertsson, Anna; Shaw, Jenny C.; Kuris, Armand M.; Amundsen, Per-Arne; Scholz, Tomáš; Lafferty, Kevin D.; Kostadinova, Aneta

2017-01-01

To identify trematode diversity and life-cycles in the sub-Arctic Lake Takvatn, Norway, we characterised 120 trematode isolates from mollusc first intermediate hosts, metacercariae from second intermediate host fishes and invertebrates, and adults from fish and invertebrate definitive hosts, using molecular techniques. Phylogenies based on nuclear and/or mtDNA revealed high species richness (24 species or species-level genetic lineages), and uncovered trematode diversity (16 putative new species) from five families typical in lake ecosystems (Allocreadiidae, Diplostomidae, Plagiorchiidae, Schistosomatidae and Strigeidae). Sampling potential invertebrate hosts allowed matching of sequence data for different stages, thus achieving molecular elucidation of trematode life-cycles and exploration of host-parasite interactions. Phylogenetic analyses also helped identify three major mollusc intermediate hosts (Radix balthica, Pisidium casertanum and Sphaerium sp.) in the lake. Our findings increase the known trematode diversity at the sub-Arctic Lake Takvatn, showing that digenean diversity is high in this otherwise depauperate sub-Arctic freshwater ecosystem, and indicating that sub-Arctic and Arctic ecosystems may be characterised by unique trematode assemblages.

Comparative Transcriptomic Exploration Reveals Unique Molecular Adaptations of Neuropathogenic Trichobilharzia to Invade and Parasitize Its Avian Definitive Host.

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Roman Leontovyč

2016-02-01

Full Text Available To date, most molecular investigations of schistosomatids have focused principally on blood flukes (schistosomes of humans. Despite the clinical importance of cercarial dermatitis in humans caused by Trichobilharzia regenti and the serious neuropathologic disease that this parasite causes in its permissive avian hosts and accidental mammalian hosts, almost nothing is known about the molecular aspects of how this fluke invades its hosts, migrates in host tissues and how it interacts with its hosts' immune system. Here, we explored selected aspects using a transcriptomic-bioinformatic approach. To do this, we sequenced, assembled and annotated the transcriptome representing two consecutive life stages (cercariae and schistosomula of T. regenti involved in the first phases of infection of the avian host. We identified key biological and metabolic pathways specific to each of these two developmental stages and also undertook comparative analyses using data available for taxonomically related blood flukes of the genus Schistosoma. Detailed comparative analyses revealed the unique involvement of carbohydrate metabolism, translation and amino acid metabolism, and calcium in T. regenti cercariae during their invasion and in growth and development, as well as the roles of cell adhesion molecules, microaerobic metabolism (citrate cycle and oxidative phosphorylation, peptidases (cathepsins and other histolytic and lysozomal proteins in schistosomula during their particular migration in neural tissues of the avian host. In conclusion, the present transcriptomic exploration provides new and significant insights into the molecular biology of T. regenti, which should underpin future genomic and proteomic investigations of T. regenti and, importantly, provides a useful starting point for a range of comparative studies of schistosomatids and other trematodes.

Molecular analysis of aspermic Fasciola flukes from Korea on the basis of the nuclear ITS1 region and mitochondrial DNA markers and comparison with Japanese aspermic Fasciola flukes.

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Ichikawa, Madoka; Itagaki, Tadashi

2012-07-01

It has been speculated that populations of aspermic Fasciola flukes in Korea and Japan have a close phylogenetic relationship. To evaluate this, we analyzed 33 Korean aspermic Fasciola flukes on the basis of nuclear ribosomal internal transcribed spacer 1 (ITS1) and mitochondrial NADH dehydrogenase subunit 1 (nad1) and cytochrome c oxidase 1 (cox1) sequences. Fh, Fg, and Fh/Fg types were detected in the ITS1 region and displayed the fragment patterns of F. hepatica, F. gigantica, and both species, respectively by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Additionally, three concatenated haplotypes of nad1 and cox1(nad1/cox1) were detected, and 2 of these, Kor1/Kor1 (Fsp1/Fsp1) haplotype and Kor2a/Kor2 (Fsp2/Fsp2) haplotype, were shared by Korean and Japanese aspermic flukes. The Fst value (0.019), calculated using the concatenated sequences, indicated that Korean and Japanese aspermic Fasciola populations were genetically undifferentiated. Interestingly, a combination of the Fh/Fg type and Kor1/Kor1 haplotype was found at the highest frequency in Korean aspermic flukes, whereas the Fg type and Fsp2/Fsp2 haplotype combination was found at a conspicuously high frequency in Japanese aspermic flukes. This indicates that a founder effect caused by the introduction of infected hosts may have played a key role in the introduction of aspermic Fasciola flukes from Korea into Japan.

Molecular characterization of Fasciola flukes obtained from wild sika deer and domestic cattle in Hokkaido, Japan.

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Ichikawa-Seki, Madoka; Shiroma, Tomoko; Kariya, Tatsuya; Nakao, Ryo; Ohari, Yuma; Hayashi, Kei; Fukumoto, Shinya

2017-10-01

The number of wild sika deer (Cervus nippon yesoensis) continues to increase in Hokkaido Prefecture, Japan. The major concern for the livestock industry is the transmission of pathogens between sika deer and cattle. Fasciolosis is an important disease that can occur in both animals. The aim of this study was to examine the possible mutual transmission of this disease in Hokkaido Prefecture. A total of 105 Fasciola flukes were obtained from sika deer and 96 from domestic cattle. The Fasciola flukes in Japan are reported to possess no mature sperm. However, in this study, 14 flukes from sika deer and eight flukes from cattle contained mature sperm in their seminal vesicles. All the Fasciola flukes from the two host animals had Fh/Fg type in nuclear phosphoenolpyruvate carboxykinase (pepck) gene, with a mixed fragment pattern derived from F. hepatica and F. gigantica, which are considered to be hybrid Fasciola flukes. However, almost all the flukes had Fsp1 haplotype in NADH dehydrogenase subunit 1 (nad1) gene, indicating that their maternal lineage was F. hepatica. A new haplotype, Fsp3, was detected in one fluke obtained from cattle and differed in one nucleotide from Fsp1. Therefore, the Fasciola flukes detected in both host species had almost identical molecular characteristics. These findings suggest the mutual transmission of Fasciola flukes between sika deer and domestic cattle in Hokkaido. Copyright © 2017. Published by Elsevier B.V.

ECTOPARASITIC TREMATODES ON Scardinius erythrophthalmus FROM THE LOWER FLOW OF THE SAVA RIVER

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Zlatko Nedić

2014-12-01

Full Text Available The research on ectoparasitic trematodes on Scardinius erythrophthalmus from the lower flow of the Sava River showed three species of trematodes, which parasitized on the fish gills and fish skin. During the study period, we sampled 120 individuals of Scardinius erythrophthalmus. In total, 85 individuals or more than 70% showed the presence of one of the three types of ectoparasitic trematodes. Determination of the trematodes was done to the species level for one species (Posthodiplosomum cuticola and to the genus level for two of them (Dactylogyrus and Gyrodactylus. Key words: Sava River, lower flow, Orašje, ectoparasitictrematodes

Landscape of the spliced leader trans-splicing mechanism in Schistosoma mansoni.

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Boroni, Mariana; Sammeth, Michael; Gava, Sandra Grossi; Jorge, Natasha Andressa Nogueira; Macedo, Andréa Mara; Machado, Carlos Renato; Mourão, Marina Moraes; Franco, Glória Regina

2018-03-01

Spliced leader dependent trans-splicing (SLTS) has been described as an important RNA regulatory process that occurs in different organisms, including the trematode Schistosoma mansoni. We identified more than seven thousand putative SLTS sites in the parasite, comprising genes with a wide spectrum of functional classes, which underlines the SLTS as a ubiquitous mechanism in the parasite. Also, SLTS gene expression levels span several orders of magnitude, showing that SLTS frequency is not determined by the expression level of the target gene, but by the presence of particular gene features facilitating or hindering the trans-splicing mechanism. Our in-depth investigation of SLTS events demonstrates widespread alternative trans-splicing (ATS) acceptor sites occurring in different regions along the entire gene body, highlighting another important role of SLTS generating alternative RNA isoforms in the parasite, besides the polycistron resolution. Particularly for introns where SLTS directly competes for the same acceptor substrate with cis-splicing, we identified for the first time additional and important features that might determine the type of splicing. Our study substantially extends the current knowledge of RNA processing by SLTS in S. mansoni, and provide basis for future studies on the trans-splicing mechanism in other eukaryotes.

Simulating the Risk of Liver Fluke Infection using a Mechanistic Hydro-epidemiological Model

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Beltrame, Ludovica; Dunne, Toby; Rose, Hannah; Walker, Josephine; Morgan, Eric; Vickerman, Peter; Wagener, Thorsten

2016-04-01

Liver Fluke (Fasciola hepatica) is a common parasite found in livestock and responsible for considerable economic losses throughout the world. Risk of infection is strongly influenced by climatic and hydrological conditions, which characterise the host environment for parasite development and transmission. Despite on-going control efforts, increases in fluke outbreaks have been reported in recent years in the UK, and have been often attributed to climate change. Currently used fluke risk models are based on empirical relationships derived between historical climate and incidence data. However, hydro-climate conditions are becoming increasingly non-stationary due to climate change and direct anthropogenic impacts such as land use change, making empirical models unsuitable for simulating future risk. In this study we introduce a mechanistic hydro-epidemiological model for Liver Fluke, which explicitly simulates habitat suitability for disease development in space and time, representing the parasite life cycle in connection with key environmental conditions. The model is used to assess patterns of Liver Fluke risk for two catchments in the UK under current and potential future climate conditions. Comparisons are made with a widely used empirical model employing different datasets, including data from regional veterinary laboratories. Results suggest that mechanistic models can achieve adequate predictive ability and support adaptive fluke control strategies under climate change scenarios.

Effect of the Filamentous Fungus Mucor circinelloides On The Development of Eggs of the Rumen Fluke Calicophoron daubneyi (Paramphistomidae).

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Arroyo, Fabián; Hernández, José A; Cazapal-Monteiro, Cristiana F; Pedreira, José; Sanchís, Jaime; Romasanta, Ángel; Sánchez-Andrade, Rita; Paz-Silva, Adolfo; Arias, María S

2017-06-01

Ruminants infected by Paramphistomidae flukes shed eggs in the feces, which pass through different stages in the environment until the infective stages (metacercariae) are reached. The activity of the soil fungus Mucor circinelloides on the development of eggs of the rumen fluke Calicophoron daubneyi was presently tested with 3 probes, i.e., in petri plates, feces, and an aqueous environment (tubes). The effect of the fungus was assessed by recording the numbers of undeveloped, nonviable, and embryonated eggs. Nonviable eggs were considered when vacuolization occurred, the inner structures were not clearly observed, the eggshell was broken, or the embryo inside was destroyed. By considering the ability of hyphae of M. circinelloides to develop in the presence of C. daubneyi eggs, attach to their surface, and penetrate and destroy the inner embryo, this ovicidal effect was classified as type 3. After a period of 50 days, the percentage of undeveloped eggs in the feces of infected cattle was 40%; furthermore, 27% of the eggs were nonviable, and 33% were embryonated (1 miracidium inside). The addition of 4 doses of M. circinelloides spores directly onto the feces resulted in 9-31% undeveloped eggs, 38-60% nonviable eggs, and 9-21% embryonated eggs, and no statistical significances were obtained among the different doses. Placing the eggs of C. daubneyi into an aqueous solution containing 10 7 spores of M. circinelloides/ml for 29 days resulted in 43% undeveloped eggs, 40% nonviable eggs, and 17% embryonated eggs, whereas in the controls, the percentages were 48%, 12%, and 40%, respectively. These data demonstrate the usefulness of the spores of the fungus M. circinelloides in limiting the development of the eggs of the trematode C. daubneyi.

Knowledge, attitude and practice related to liver fluke infection in northeast Thailand

Institute of Scientific and Technical Information of China (English)

Natthawut Kaewpitoon; Soraya J Kaewpitoon; Prasit Pengsaa; Chutigan Pilasri

2007-01-01

AIM:To investigate the knowledge,attitude and practice (KAP) in prevention and control of liver fluke infection in northeast Thailand.METHODS:A descriptive KAP survey pertaining to liver fluke infection was carried out in June 2005 to October 2006 using structured questionnaires. Data were collected by questionnaires consisting of general parameters,knowledge,attitude,practice,and a history of participation in the prevention and control of liver fluke infection.RESULTS:A total of 1077 persons who were interviewed and completed the questionnaires were enrolled in the study. The majority were females (69.5%) and many of them were 15-20 years of age (37.26%). The questionnaires revealed that information resources on Uver fluke infection included local public health volunteers (31.37%),public health officers (18.72%),televisions (14.38%),local heads of sub-districts (12.31%),doctors and nurses (9.18%),newspaper (5.72),internets (5.37%),and others (12.95%). Fifty-five point eleven percent of the population had a good level of liver fluke knowledge concerning the mode of disease transmission and 79.72% of the population had a good level of prevention and control knowledge with regards to defecation and consumption. The attitude and practice in liver fluke prevention and control were also at a good level with a positive awareness,participation,and satisfaction of 72.1% and 60.83% of the persons studied. However,good health behavior was found in 39.26% and 41.42% of the persons studied who had unhygienic defecation and ate raw cyprinoid's fish. Theresult also showed that 41.25% of the persons studied previously joined prevention and control campaigns.CONCLUSION:The persons studied have a high level of liver fluke knowledge and positive attitude. However,improvement is required regarding personal hygiene specifically with hygienic defecation and consumption of undercooked fish.

Trematode diversity in freshwater fishes of the Globe II: 'New World'.

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Choudhury, Anindo; Aguirre-Macedo, M Leopoldina; Curran, Stephen S; de Núñez, Margarita Ostrowski; Overstreet, Robin M; de León, Gerardo Pérez-Ponce; Santos, Cláudia Portes

2016-03-01

We provide a summary overview of the diversity of trematode parasites in freshwater fishes of the 'New World', i.e. the Americas, with emphasis on adult forms. The trematode fauna of three regions, South America, Middle America, and USA and Canada (North America north of Mexico), are considered separately. In total, 462 trematode species have been reported as adults from the Americas. The proportion of host species examined for parasites varies widely across the Americas, from a high of 45% in the Mexican region of Middle America to less than 5% in South America. North and South America share no adult species, and one exclusively freshwater genus, Creptotrema Travassos, Artigas & Pereira, 1928 in the Allocreadiidae Looss, 1902 is the most widely distributed. Metacercariae of strigeiforms maturing in fish-eating birds (e.g. species of the Diplostomidae Poirier, 1886) are common and widely distributed. The review also highlights the paucity of known life-cycles. The foreseeable future of diversity studies belongs to integrative approaches and the application of molecular ecological methods. While opportunistic sampling will remain important in describing and cataloguing the trematode fauna, a better understanding of trematode diversity and biology will also depend on strategic sampling throughout the Americas.

Cross-sectional study of Fasciola gigantica and other trematode infections of cattle in Edu Local Government Area, Kwara State, north-central Nigeria.

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Elelu, Nusirat; Ambali, Abdulganiyu; Coles, Gerald C; Eisler, Mark C

2016-08-26

Trematode infections of livestock are of global veterinary and public health importance causing serious economic losses. Majority of data on burden of trematode infections in Nigeria are based on abattoir surveys and there are very few data on herd level risk factors. The present study investigated the prevalence of, and herd level risk factors for, fasciolosis and other trematode infections in cattle in Edu Local Government Area (LGA). A cross-sectional survey used two-stage study design to investigate cattle belonging to 65 households. Two questionnaires were administered for household-level and individual cattle-level data. Faecal and blood samples were obtained from the cattle. Logistic regression analyses were performed to determine risk factors for infections. Of 686 faecal samples analysed, 74.9 %, 16.1 %, 7.3 % and 1.2 % were positive for infections with Fasciola gigantica, paramphistomes, Dicrocoelium hospes and Schistosoma bovis respectively. Fasciola gigantica had higher prevalence in adult cattle (77.3 %) than weaners (62.5 %). Majority of co-infections was a combination of F. gigantica with paramphistomes 84/130 (64.6 %). Most (58.9 %) of the cattle belonged to FAMACHA© score 2. The mean packed cell volume (PCV) was 34.4 %. The sensitivity and specificity of FAMACHA© for anaemia (PCV < 24 %) were 18.2 and 96.9 %, respectively. Positive correlation was obtained between faecal egg counts for F. gigantica and paramphistomes (R = 0.15, P = 0.0001). Adult cattle were more likely to be infected with F. gigantica (odds ratio, OR: 1.94; Confidence Interval, CI: 1.19-3.16) than weaners. Cattle belonging to household heads aged between 40-59 years were more likely infected with paramphistomes (OR: 1.95; CI: 1.02-3.74) than those belonging to other age groups. Cattles from herds with size ≥ 100 were more likely infected with D. hospes than those from smaller herds (OR: 6.98; CI: 2.94-16.6). This study revealed high prevalence of

The Fluke Security Project

Science.gov (United States)

2000-04-01

be an extension of Utah’s nascent Quarks system, oriented to closely coupled cluster environments. However, the grant did not actually begin until... Intel x86, implemented ten virtual machine monitors and servers, including a virtual memory manager, a checkpointer, a process manager, a file server...Fluke, we developed a novel hierarchical processor scheduling frame- work called CPU inheritance scheduling [5]. This is a framework for scheduling

The draft genome of the carcinogenic human liver fluke Clonorchis sinensis

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2011-01-01

Background Clonorchis sinensis is a carcinogenic human liver fluke that is widespread in Asian countries. Increasing infection rates of this neglected tropical disease are leading to negative economic and public health consequences in affected regions. Experimental and epidemiological studies have shown a strong association between the incidence of cholangiocarcinoma and the infection rate of C. sinensis. To aid research into this organism, we have sequenced its genome. Results We combined de novo sequencing with computational techniques to provide new information about the biology of this liver fluke. The assembled genome has a total size of 516 Mb with a scaffold N50 length of 42 kb. Approximately 16,000 reliable protein-coding gene models were predicted. Genes for the complete pathways for glycolysis, the Krebs cycle and fatty acid metabolism were found, but key genes involved in fatty acid biosynthesis are missing from the genome, reflecting the parasitic lifestyle of a liver fluke that receives lipids from the bile of its host. We also identified pathogenic molecules that may contribute to liver fluke-induced hepatobiliary diseases. Large proteins such as multifunctional secreted proteases and tegumental proteins were identified as potential targets for the development of drugs and vaccines. Conclusions This study provides valuable genomic information about the human liver fluke C. sinensis and adds to our knowledge on the biology of the parasite. The draft genome will serve as a platform to develop new strategies for parasite control. PMID:22023798

In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import.

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Peterson, Nathan A; Anderson, Tavis K; Wu, Xiao-Jun; Yoshino, Timothy P

2013-07-09

Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous localization of highly

Host density increases parasite recruitment but decreases host risk in a snail-trematode system.

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Buck, J C; Hechinger, R F; Wood, A C; Stewart, T E; Kuris, A M; Lafferty, K D

2017-08-01

Most species aggregate in local patches. High host density in patches increases contact rate between hosts and parasites, increasing parasite transmission success. At the same time, for environmentally transmitted parasites, high host density can decrease infection risk to individual hosts, because infective stages are divided among all hosts in a patch, leading to safety in numbers. We tested these predictions using the California horn snail, Cerithideopsis californica (=Cerithidea californica), which is the first intermediate host for at least 19 digenean trematode species in California estuaries. Snails become infected by ingesting trematode eggs or through penetration by free-swimming miracidia that hatch from trematode eggs deposited with final-host (bird or mammal) feces. This complex life cycle decouples infective-stage production from transmission, raising the possibility of an inverse relationship between host density and infection risk at local scales. In a field survey, higher snail density was associated with increased trematode (infected snail) density, but decreased trematode prevalence, consistent with either safety in numbers, parasitic castration, or both. To determine the extent to which safety in numbers drove the negative snail-density-trematode-prevalence association, we manipulated uninfected snail density in 83 cages at eight sites within Carpinteria Salt Marsh (California, USA). At each site, we quantified snail density and used data on final-host (bird and raccoon) distributions to control for between-site variation in infective-stage supply. After three months, overall trematode infections per cage increased with snail biomass density. For egg-transmitted trematodes, per-snail infection risk decreased with snail biomass density in the cage and surrounding area, whereas per-snail infection risk did not decrease for miracidium-transmitted trematodes. Furthermore, both trematode recruitment and infection risk increased with infective

Pharmacological and morphological characteristics of the muscular system of the giant liver fluke (Fascioloides magna - Bassi 1875).

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Trailović, Saša M; Marinković, Darko; Trailović, Jelena Nedeljković; Milovanović, Mirjana; Marjanović, Djordje S; Aničić, Milan R

2015-12-01

Motility is required for feeding, reproduction and maintenance of the fluke in the host's liver. According to that, the neuromuscular system can be an attractive drugable target for chemotherapy. Musculature of the Fascioloides magna is organized into three layers, an outer circular layer, beneath this layer the longitudinal layer, and third, the oblique, or diagonal layer underlies the longitudinal layer. In our study, the administration of atropine or caffeine did not cause classic muscle contractions of F. magna muscle strips. However, the Electrical Field Stimulation (EFS) induced stable and repeatable contractions, which enabled us to examine their sensitivity to the various substances. Acetylcholine (ACh) (300 μM and 1 mM), caused only a slight relaxation, without affecting the amplitude of spontaneous contractions or the amplitude of contractions induced by EFS. Contrary to that, atropine (100 μM) caused a significant increase in the basal tone and an increase of EFS-induced contractions. If acetylcholine is an inhibitory neurotransmitter in trematodes, the described effects of atropine are achieved by the blockade of inhibitory neurotransmission. On the other hand, with respect to the process of excitation-contraction coupling, the plant alkaloid ryanodine (30 μM) significantly reduced the basal tone, as well as EFS-induced contractions of F. magna muscle strips. Ryanodine inhibited the potentiating effect of atropine on the basal tone and contractions caused by EFS, which indicates that the contractile effect of atropine is dependent on Ca(++) release from intracellular stores. Caffeine (500 μM) caused relaxation of fluke muscle strips and at the same time significantly enhanced the EFS-induced contractions. Both effects of caffeine can be explained by entry of extracellular Ca(++) into muscle cells. The muscle contractility of F. magna depends both on the entry of extracellular calcium, and calcium release from intracellular stores, which are

Relationships between nutrient enrichment, pleurocerid snail density and trematode infection rate in streams

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Ciparis, Serena; Iwanowicz, Deborah D.; Voshell, J. Reese

2013-01-01

Summary 1. Nutrient enrichment is a widespread environmental problem in freshwater ecosystems. Eutrophic conditions caused by nutrient enrichment may result in a higher prevalence of infection by trematode parasites in host populations, due to greater resource availability for the molluscan first intermediate hosts. 2. This study examined relationships among land use, environmental variables indicating eutrophication, population density of the pleurocerid snail, Leptoxis carinata, and trematode infections. Fifteen study sites were located in streams within the Shenandoah River catchment (Virginia, U.S.A.), where widespread nutrient enrichment has occurred. 3. Snail population density had a weak positive relationship with stream water nutrient concentration. Snail population density also increased as human activities within stream catchments increased, but density did not continue to increase in catchments where anthropogenic disturbance was greatest. 4. Cercariae from five families of trematodes were identified in L. carinata, and infection rate was generally low (<10%). Neither total infection rate nor the infection rate of individual trematode types showed a positive relationship with snail population density, nutrients or land use. 5. There were statistically significant but weak relationships between the prevalence of infection by two trematode families and physical and biological variables. The prevalence of Notocotylidae was positively related to water depth, which may be related to habitat use by definitive hosts. Prevalence of Opecoelidae had a negative relationship with orthophosphate concentration and a polynomial relationship with chlorophyll a concentration. Transmission of Opecoelid trematodes between hosts may be inhibited by eutrophic conditions. 6. Leptoxis carinata appears to be a useful species for monitoring the biological effects of eutrophication and investigating trematode transmission dynamics in lotic systems.

A systematically improved high quality genome and transcriptome of the human blood fluke Schistosoma mansoni.

Directory of Open Access Journals (Sweden)

Anna V Protasio

2012-01-01

Full Text Available Schistosomiasis is one of the most prevalent parasitic diseases, affecting millions of people in developing countries. Amongst the human-infective species, Schistosoma mansoni is also the most commonly used in the laboratory and here we present the systematic improvement of its draft genome. We used Sanger capillary and deep-coverage Illumina sequencing from clonal worms to upgrade the highly fragmented draft 380 Mb genome to one with only 885 scaffolds and more than 81% of the bases organised into chromosomes. We have also used transcriptome sequencing (RNA-seq from four time points in the parasite's life cycle to refine gene predictions and profile their expression. More than 45% of predicted genes have been extensively modified and the total number has been reduced from 11,807 to 10,852. Using the new version of the genome, we identified trans-splicing events occurring in at least 11% of genes and identified clear cases where it is used to resolve polycistronic transcripts. We have produced a high-resolution map of temporal changes in expression for 9,535 genes, covering an unprecedented dynamic range for this organism. All of these data have been consolidated into a searchable format within the GeneDB (www.genedb.org and SchistoDB (www.schistodb.net databases. With further transcriptional profiling and genome sequencing increasingly accessible, the upgraded genome will form a fundamental dataset to underpin further advances in schistosome research.

On the presence and immunoregulatory functions of extracellular microRNAs in the trematode Fasciola hepatica.

Science.gov (United States)

Fromm, B; Ovchinnikov, V; Høye, E; Bernal, D; Hackenberg, M; Marcilla, A

2017-02-01

Liver flukes represent a paraphyletic group of endoparasitic flatworms that significantly affect man either indirectly due to economic damage on livestock or directly as pathogens. A range of studies have focussed on how these macroscopic organisms can evade the immune system and live inside a hostile environment such as the mammalian liver and bile ducts. Recently, microRNAs, a class of short noncoding gene regulators, have been proposed as likely candidates to play roles in this scenario. MicroRNAs (miRNAs) are key players in development and pathogenicity and are highly conserved between metazoans: identical miRNAs can be found in flatworms and mammalians. Interestingly, miRNAs are enriched in extracellular vesicles (EVs) which are secreted by most cells. EVs constitute an important mode of parasite/host interaction, and recent data illustrate that miRNAs play a vital part. We have demonstrated the presence of miRNAs in the EVs of the trematode species Dicrocoelium dendriticum and Fasciola hepatica (Fhe) and identified potential immune-regulatory miRNAs with targets in the host. After our initial identification of miRNAs expressed by F. hepatica, an assembled genome and additional miRNA data became available. This has enabled us to update the known complement of miRNAs in EVs and speculate on potential immune-regulatory functions that we review here. © 2016 John Wiley & Sons Ltd.

Description of spermatogenesis and sperm ultrastructure of Acanthostomum (Atrophocaecum aswaninesis Wannas, 1977 (Digenea, Acanthostomatidae, a parasite of Bagrus bayad in Egypt

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A.A. Taeleb

2013-03-01

The spermiogenesis process and spermatozoon organization of A. (A. aswaninesis match the general pattern found in the digenea, but certain peculiarities are characteristic and differentiate the sperm of this fluke from that of other digenetic trematodes.

A case of a facultative life-cycle diversification in the fluke Pleurogenoides sp. (Lecithodendriidae, Plagiorchiida).

Science.gov (United States)

Hassl, Andreas R

2010-10-01

Numerous specimens of the native, intestinal digenean fluke Pleurogenoides sp. (Lecithodendriidae, Plagiorchiida), a genus known for the simultaneous co-existence of genuine adults and progenetic, adult-like metacercaria, were found by chance parasitizing in the oesophagus of a recently imported, tropical Bristly Bush Viper (Atheris hispida). The snake had before been force-fed with native water frogs, the assumed definitive host of these flukes. Hence water frogs act as the second intermediate host or as a paratenic host for Pleurogenoides flukes, as they must house progenetic fluke larvae, which develop to genuine adults when transmitted to an appropriate consecutive host, the ancestral definitive host, a reptile. The European Pleurogenoides fluke species seem to display a facultative life-cycle diversification, they can adjust their life-history strategy according to their immediate transmission opportunities. This phenotypic plasticity allows the parasite to respond quickly to any changes in the abundance of a host; usually this biological oddity results in a life-cycle truncation by the elimination of the definitive host.

Potential role of hares in the spread of liver fluke in the Netherlands

NARCIS (Netherlands)

Walker, S.M.; Johnston, C.; Hoey, E.M.; Fairweather, I.; Borgsteede, F.H.M.; Gaasenbeek, C.P.H.; Prodohl, P.A.; Trudgett, A.

2011-01-01

Hares (Lepus europeanus) sharing pasture with cattle from six locations in the Netherlands were examined for the presence of liver fluke (Fasciola hepatica) and shown to have prevalences of infection ranging from 0 to 41%. The mitochondrial haplotypes of liver flukes present in the hare populations

The role of evolutionary biology in research and control of liver flukes in Southeast Asia.

Science.gov (United States)

Echaubard, Pierre; Sripa, Banchob; Mallory, Frank F; Wilcox, Bruce A

2016-09-01

Stimulated largely by the availability of new technology, biomedical research at the molecular-level and chemical-based control approaches arguably dominate the field of infectious diseases. Along with this, the proximate view of disease etiology predominates to the exclusion of the ultimate, evolutionary biology-based, causation perspective. Yet, historically and up to today, research in evolutionary biology has provided much of the foundation for understanding the mechanisms underlying disease transmission dynamics, virulence, and the design of effective integrated control strategies. Here we review the state of knowledge regarding the biology of Asian liver Fluke-host relationship, parasitology, phylodynamics, drug-based interventions and liver Fluke-related cancer etiology from an evolutionary biology perspective. We consider how evolutionary principles, mechanisms and research methods could help refine our understanding of clinical disease associated with infection by Liver Flukes as well as their transmission dynamics. We identify a series of questions for an evolutionary biology research agenda for the liver Fluke that should contribute to an increased understanding of liver Fluke-associated diseases. Finally, we describe an integrative evolutionary medicine approach to liver Fluke prevention and control highlighting the need to better contextualize interventions within a broader human health and sustainable development framework. Copyright © 2016 Elsevier B.V. All rights reserved.

Glucose Uptake in the Human Pathogen Schistosoma mansoni Is Regulated Through Akt/Protein Kinase B Signaling.

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McKenzie, Maxine; Kirk, Ruth S; Walker, Anthony J

2018-06-05

In Schistosoma mansoni, the facilitated glucose transporter SGTP4, which is expressed uniquely in the apical surface tegumental membranes of the parasite, imports glucose from host blood to support its growth, development, and reproduction. However, the molecular mechanisms that underpin glucose uptake in this blood fluke are not understood. In this study we employed techniques including Western blotting, immunolocalization, confocal laser scanning microscopy, pharmacological assays, and RNA interference to functionally characterize and map activated Akt in S mansoni. We find that Akt, which could be activated by host insulin and l-arginine, was active in the tegument layer of both schistosomules and adult worms. Blockade of Akt attenuated the expression and evolution of SGTP4 at the surface of the host-invading larval parasite life-stage, and suppressed SGTP4 expression at the tegument in adults; concomitant glucose uptake by the parasite was also attenuated in both scenarios. These findings shed light on crucial mechanistic signaling processes that underpin the energetics of glucose uptake in schistosomes, which may open up novel avenues for antischistosome drug development.

Conflict of interest between a nematode and a trematode in an amphipod host: Test of the "sabotage" hypothesis

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Thomas, Frédéric; Fauchier, Jerome; Lafferty, Kevin D.

2002-01-01

Microphallus papillorobustus is a manipulative trematode that induces strong behavioural alterations in the gamaridean amphipod Gammarus insensibilis, making the amphipod more vulnerable to predation by aquatic birds (definitive hosts). Conversely, the sympatric nematodeGammarinema gammari uses Gammarus insensibilis as a habitat and a source of nutrition. We investigated the conflict of interest between these two parasite species by studying the consequences of mixed infection on amphipod behaviour associated with the trematode. In the field, some amphipods infected by the trematode did not display the altered behaviour. These normal amphipods also had more nematodes, suggesting that the nematode overpowered the manipulation of the trematode, a strategy that would prolong the nematode's life. We hypothesize that sabotage of the trematode by the nematode would be an adaptive strategy for the nematode consistent with recent speculation about co-operation and conflict in manipulative parasites. A behavioural test conducted in the laboratory from naturally infected amphipods yielded the same result. However, exposing amphipods to nematodes did not negate or decrease the manipulation exerted by the trematode. Similarly, experimental elimination of nematodes from amphipods did not permit trematodes to manipulate behaviour. These experimental data do not support the hypothesis that the negative association between nematodes and manipulation by the trematode is a result of the "sabotage" hypothesis.

Studies on Urinary Schistosomiasis in Selected Villages around ...

African Journals Online (AJOL)

1Department of Biological Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria. 2Department of ... caused by blood flukes of the genus Schistosoma and ..... Teaching/5480/samplesize.htm ... Evaluation of three diagnostic techniques.

Invasion of Flukes of the Echinostomatidae Family in Racing Pigeon ( Columba livia var. domestica) Lofts.

Science.gov (United States)

Ledwoń, Aleksandra; Dolka, Beata; Piasecki, Tomasz; Dolka, Izabella; Szeleszczuk, Piotr

2016-06-01

Over 4 years, only two known cases of fluke invasions were diagnosed in racing pigeons ( Columba livia ) originating from different regions of Poland. In both cases, the invasion was characterized by a very high mortality (approximately 70%), and the source of the infestation was snails of the Lymnaeidae family eaten by pigeons. Fluke invasions in pigeons are extremely rare and to date have not been described in Poland. Therefore, the occurrence of the symptoms of hemorrhagic diarrhea and sudden deaths of either adult pigeons or nestlings were suspected to be associated with poisoning. Autopsy revealed an invasion of flukes causing hemorrhagic enteritis. Renal failure and spleen atrophy were also found in the birds. Using molecular biology techniques, infestation with the fluke Echinostoma revolutum was determined in the second case.

Reducing liver fluke transmission in northeastern Thailand | IDRC ...

International Development Research Centre (IDRC) Digital Library (Canada)

2016-04-29

Apr 29, 2016 ... ... leaders, local health officials, school teachers—were agents of change. ... visited 186 households and organized liver fluke campaigns in local schools, ... The Lawa Model has since gained national and international ...

Application of tracer techniques to the study of trematode infections: Pathological and epidemiological aspects

International Nuclear Information System (INIS)

Nansen, P.

1976-01-01

Liver fluke and blood fluke infections cause heavy losses in animal production. The infections are characterized by a concomitant anaemia and dysproteinaemia. A review is made of radioisotopic tracer studies which have contributed to an understanding of the dynamic processes underlying the blood changes. Such studies have provided important information about the activity of the parasites, for example, how they cause disease and how they influence animal production. Radioisotopic techniques have also been utilized in the study of free-living fluke larvae. A brief outline of principles and fields if investigations within this area is given. (author)

Production of marine trematode cercariae: a potentially overlooked path of energy flow in benthic systems

DEFF Research Database (Denmark)

Thieltges, David W.; de Montaudouin, Xavier; Fredensborg, Brian

2008-01-01

Parasites, in particular trematodes, are unseen but ubiquitous components of marine intertidal ecosystems. Although parasites are known to affect population dynamics and food web structure, their potential function as an unrecognized path of energy flow in these ecosystems is yet to be quantified...... in different marine benthic systems. Across 18 trematode species, cercarial output (no. cercariae shed snail-1 d-1) ranged over 4 orders of magnitude and was positively correlated with snail host species size. While cercarial output did not correlate with latitude, it did correlate negatively with the size...... reported for free-living invertebrates inhabiting benthic ecosystems. These estimates would be much higher if they included all trematode species in an ecosystem, and not just single-species values. Overall, results suggest that trematode cercariae represent potentially important paths of energy flow...

Egg-specific expression of protein with DNA methyltransferase activity in the biocarcinogenic liver fluke Clonorchis sinensis.

Science.gov (United States)

Kim, Seon-Hee; Cho, Hye-Jeong; Sohn, Woon-Mok; Ahn, Chun-Seob; Kong, Yoon; Yang, Hyun-Jong; Bae, Young-An

2015-08-01

Despite recent reports regarding the biology of cytosine methylation in Schistosoma mansoni, the impact of the regulatory machinery remains unclear in diverse platyhelminthes. This ambiguity is reinforced by discoveries of DNA methyltransferase 2 (DNMT2)-only organisms and the substrate specificity of DNMT2 preferential to RNA molecules. Here, we characterized a novel DNA methyltransferase, named CsDNMT2, in a liver fluke Clonorchis sinensis. The protein exhibited structural properties conserved in other members of the DNMT2 family. The native and recombinant CsDNMT2 exhibited considerable enzymatic activity on DNA. The spatiotemporal expression of CsDNMT2 mirrored that of 5-methylcytosine (5 mC), both of which were elevated in the C. sinensis eggs. However, CsDNMT2 and 5 mC were marginally detected in other histological regions of C. sinensis adults including ovaries and seminal receptacle. The methylation site seemed not related to genomic loci occupied by progenies of an active long-terminal-repeat retrotransposon. Taken together, our data strongly suggest that C. sinensis has preserved the functional DNA methylation machinery and that DNMT2 acts as a genuine alternative to DNMT1/DNMT3 to methylate DNA in the DNMT2-only organism. The epigenetic regulation would target functional genes primarily involved in the formation and/or maturation of eggs, rather than retrotransposons.

Effect of wide spectrum anti-helminthic drugs upon Schistosoma mansoni experimentally infected mice

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PANCERA Christiane Finardi

1997-01-01

Full Text Available Mebendazole, albendazole, levamisole and thiabendazole are well known as active drugs against several nematode species, and against cestodes as well, when the first two drugs are considered. None of the drugs have proven activity, however, against trematodes. We tested the effect of these drugs on the fecal shedding of schistosome eggs and the recovering of adult schistosomes, after portal perfusion in Schistosoma mansoni experimentally infected mice. Balb/c mice infected with 80 S. mansoni cercariae were divided into three groups, each in turn subdivided into four other groups, for each tested drug. The first group was treated with each one of the studied drugs 25 days after S. mansoni infection; the second group was submitted to treatment with each one of the drugs 60 days after infection. Finally, the third group, considered as control, received no treatment. No effect upon fecal shedding of S. mansoni eggs and recovering of schistosomes after portal perfusion was observed when mice were treated with either mebendazole or albendazole. Mice treated with either levamisole or thiabendazole, on the other hand, showed a significant reduction in the recovering of adult schistosomes after portal perfusion, mainly when both drugs were given during the schistosomula evolution period, i.e., 25 days after cercariae penetration, probably due to unspecific immunomodulation

A Histopathology Study of Caspian Seal (Pusa caspica (Phocidae, Mammalia Liver Infected with Trematode, Pseudamphistomum truncatum (Rudolphi, 1819 (Opisthorchidae, Trematoda.

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Richard Heckmann

2014-06-01

Full Text Available Main objective of this study was to investigate the invasive activity of the liver fluke, Pseudamphistomom truncatum against the Caspian seal (Pusa caspica and was exemplified at the gross, light microscopy (LM and electron microscopy (EM levels.The study was done on a freshly dead Caspian Seal in the southern coast of Caspian Sea. The checked Caspian seal probably being died of canine distemper virus and was found host to numerous parasites of four helminth species.P. truncatum caused edematous foci on the surface of the liver with prominent fluid accumulation. Sections of the liver viewed with LM had multiple necrotic areas with extensive hemorrhaging and disorganized hepatic lobules. Granulocytes and invasion of connective tissue were prominent. Whole worms were visible with invasive pathways through the host tissue. Damage to both hepatic ducts and blood vessels were prominent. At the EM level, organelles within the impacted hepatocytes were disorganized as exemplified by the cristae of the mitochondria and the endoplasmic reticulum. Parasite eggs were scattered throughout the tissue.It was shown that this trematode can be very pathogenic to Caspian Seal and as this only mammal of Caspian Sea is an endangered species; this needs more investigation toward control or possible treatment of this helminth.

Prevalence of cattle flukes infection at Andassa Livestock Research Center in north-west of Ethiopia

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Asressa Yeneneh

2012-06-01

Full Text Available A cross sectional study was carried out from October 2010 to March 2011 at Andassa Livestock Research Center, North-West Ethiopia. The objective was to determine the prevalence of cattle flukes infection. Faecal samples were collected from a total of 384 cattle, cross breed (n= 39 and Fogera breed (n=345 of all age groups and sex. Sedimentation technique was employed for the recovery of fluke eggs from freshly collected fecal sample. The results indicated that the overall prevalence of bovine flukes infection was 60.42%. In this study, the highest prevalence was recorded from Paramphistomosis (45.83% followed by Fasciolosis (23.96%, and Schistosomosis (9.89%. The prevalence of flukes infection was higher in age group 1- 2 years old. There was significant difference in case of Paramphistomosis among age groups. No significant association was found between crossed breeds and sex groups for fluke’s infection. The prevalence of Paramphistomosis was high in cross breed (58.97% than Fogera breed (44.35%. However, in both cases, there was no significant difference. The result of the present study revealed that the prevalence of major bovine fluke infection in the study area was relatively low and is the definite proof of active infection.

Trace Fossil Evidence of Trematode-Bivalve Parasite-Host Interactions in Deep Time.

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Huntley, John Warren; De Baets, Kenneth

2015-01-01

Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, almost nothing is known about its history in deep time. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. These malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this review, we present the various malformations induced by trematodes in bivalves, evaluate their distribution through deep time in the phylogenetic and ecological contexts of their bivalve hosts and explore how various taphonomic processes have likely biased our understanding of trematodes in deep time. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behaviour making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony and suggest a practical methodology for testing such hypotheses in deep time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Liver fluke (Fasciola hepatica) infection in cattle in Northern Ireland: a large-scale epidemiological investigation utilising surveillance data.

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Byrne, Andrew W; McBride, Stewart; Lahuerta-Marin, Angela; Guelbenzu, Maria; McNair, Jim; Skuce, Robin A; McDowell, Stanley W J

2016-04-14

Liver fluke (Fasciola hepatica) is a widespread parasite of ruminants which can have significant economic impact on cattle production. Fluke infection status at the animal-level is captured during meat inspection of all animals processed for human consumption within Northern Ireland. These national datasets have not been analysed to assess their utility in uncovering patterns in fluke infection at animal- and herd-levels in Northern Ireland. We utilised a dataset of 1.2 million animal records from ~18,000 herds across 3 years (2011-2013) to assess animal- and herd-level apparent prevalence and risk-factors associated with fluke infection. Animal-level apparent prevalence was measured as the proportion of animals exhibiting evidence of fluke infection at slaughter; between herd-level infection prevalence was measured by binary categorisation of herds (infected or not). "Within herd" infection prevalence was measured using the proportion of animals within a herd that showed evidence of fluke infection per year (ranging from 0-100%). "Within herd" infection prevalence at the herd level was investigated using multivariable modelling. At the animal level, the proportion of animals slaughtered that exhibited evidence of infection was 21-25% amongst years. Across herds, the proportion of herds with at least one infected animal, varied between 61 and 65%. However, there was a significant sampling effect at the herd-level; all herds where at least 105 animals slaughtered over the study period exhibited evidence of fluke infection (100%). There was significant variation in terms of within-herd infection prevalence. Risk factors included herd type, long-term weather variation, geographic location (region) and the abattoir. Liver fluke apparent prevalence was high at the herd-level across years. However, there was lower prevalence at the animal level, which may indicate significant variation in the exposure to fluke infection within herds. The proportion infected within

Trematode infection among freshwater gastropods in Tessaout ...

African Journals Online (AJOL)

In the summer of 1994 and the spring of 1995, a snail survey aimed at determining relationships between the distribution of molluscan fauna, various environmental factors and trematode infection was carried out in the Tessaout Amont irrigation system, Morocco. The molluscan fauna consisted of nine species belonging to ...

Transcriptome analysis of Schistosoma mansoni larval development using serial analysis of gene expression (SAGE).

Science.gov (United States)

Taft, A S; Vermeire, J J; Bernier, J; Birkeland, S R; Cipriano, M J; Papa, A R; McArthur, A G; Yoshino, T P

2009-04-01

Infection of the snail, Biomphalaria glabrata, by the free-swimming miracidial stage of the human blood fluke, Schistosoma mansoni, and its subsequent development to the parasitic sporocyst stage is critical to establishment of viable infections and continued human transmission. We performed a genome-wide expression analysis of the S. mansoni miracidia and developing sporocyst using Long Serial Analysis of Gene Expression (LongSAGE). Five cDNA libraries were constructed from miracidia and in vitro cultured 6- and 20-day-old sporocysts maintained in sporocyst medium (SM) or in SM conditioned by previous cultivation with cells of the B. glabrata embryonic (Bge) cell line. We generated 21 440 SAGE tags and mapped 13 381 to the S. mansoni gene predictions (v4.0e) either by estimating theoretical 3' UTR lengths or using existing 3' EST sequence data. Overall, 432 transcripts were found to be differentially expressed amongst all 5 libraries. In total, 172 tags were differentially expressed between miracidia and 6-day conditioned sporocysts and 152 were differentially expressed between miracidia and 6-day unconditioned sporocysts. In addition, 53 and 45 tags, respectively, were differentially expressed in 6-day and 20-day cultured sporocysts, due to the effects of exposure to Bge cell-conditioned medium.

Trematodes of fishes of the Indo-west Pacific: told and untold richness.

Science.gov (United States)

Cribb, Thomas H; Bray, Rodney A; Diaz, Pablo E; Huston, Daniel C; Kudlai, Olena; Martin, Storm B; Yong, Russell Q-Y; Cutmore, Scott C

2016-03-01

The Indo-west Pacific is a marine bioregion stretching from the east coast of Africa to Hawaii, French Polynesia and Easter Island. An assessment of the literature from the region found reports of 2,582 trematode species infecting 1,485 fish species. Reports are concentrated in larger fishes, undoubtedly reflecting the tendency for larger hosts to be infected by more species of parasites as well as a collecting bias. Many hundreds of fish species, including many from families known to be rich in trematodes, have yet to be reported as hosts. Despite some areas (the Great Barrier Reef, Hawaii and the waters off China, India and Japan) receiving sustained attention, none can be considered to be comprehensively known. Several regions, most importantly in East Africa, French Polynesia and the Coral Triangle, are especially poorly known. The fauna of the Indo-west Pacific has been reported so unevenly that we consider it impossible to predict the true trematode richness for the region. We conclude that the greatest gap in our understanding is of the geographical distribution of species in the Indo-west Pacific. This is highlighted by the fact that 87% of trematodes in the region have been reported no more than five times. The reliable recognition of species is a major problem in this field; molecular approaches offer prospects for resolution of species identification but have been little adopted to date.

DISCRIMINATION 28S RIBOSOMAL GENE OF TREMATODE CERCARIAE IN SNAILS FROM CHIANG MAI PROVINCE, THAILAND.

Science.gov (United States)

Wongsawad, Chalobol; Wongsawad, Pheravut; Sukontason, Kom; Phalee, Anawat; Noikong-Phalee, Waraporn; Chai, Jong Yil

2016-03-01

Trematode cercariae are commonly found in many freshwater gastropods. These cercariae can serve to identify the occurrence of such trematodes as Centrocestus formosanus, Haplorchis taichui, Haplorchoides sp, and Stellantchasmus falcatus, which are important parasites in Chiang Mai Province, Thailand. As the species of these cercariae cannot be identified accurately based on morphology, this study employed sequencing of a fragment of 28S ribosomal DNA and phylogenetic analysis to identify the trematode cercariae found in freshwater gastropods in Chiang Mai Province. Eight types of trematode cercariae were identified, namely, distome cercaria (grouped with Philophthalmus spp clade), echinostome cercaria (grouped with Echinostoma spp clade), furcocercous cercaria (grouped with Posthodiplostomum sp/Alaria taxideae/Hysteromorpha triloba clade), monostome cercaria (grouped with Catatropis indicus clade), parapleurolophocercous cercaria (grouped with Haplorchoides sp clade), pleurolophocercous cercaria (grouped with Centrocestusformosanus clade), transversotrema cercaria (grouped with Transversotrema spp clade), and xiphidiocercaria (grouped with Prosthodendrium spp clade). These results provide important information that can be used for identifying these parasites in epidemiological surveys.

Hybrid origin of Asian aspermic Fasciola flukes is confirmed by analyzing two single-copy genes, pepck and pold

Science.gov (United States)

HAYASHI, Kei; ICHIKAWA-SEKI, Madoka; MOHANTA, Uday Kumar; SHORIKI, Takuya; CHAICHANASAK, Pannigan; ITAGAKI, Tadashi

2017-01-01

Nuclear gene markers, phosphoenolpyruvate carboxykinase (pepck) and DNA polymerase delta (pold), have been developed for precise discrimination of Fasciola flukes instead of internal transcribed spacer 1. In this study, these two genes of 730 Fasciola flukes from eight Asian countries were analyzed. The results were compared with their mitochondrial NADH dehydrogenase subunit 1 (nad1) lineages for obtaining a definitive evidence of the hybrid origin of aspermic Fasciola flukes. All the flukes categorized into the aspermic nad1 lineages possessed both the fragment patterns of F. hepatica and F. gigantica (mixed types) in pepck and/or pold. These findings provide clear evidence for the hybrid origin of aspermic Fasciola lineages and suggest that “aspermic Fasciola flukes” should hereafter be called “hybrid Fasciola flukes”. PMID:29187710

Development of functional genomic tools in trematodes: RNA interference and luciferase reporter gene activity in Fasciola hepatica.

Directory of Open Access Journals (Sweden)

Gabriel Rinaldi

2008-07-01

Full Text Available The growing availability of sequence information from diverse parasites through genomic and transcriptomic projects offer new opportunities for the identification of key mediators in the parasite-host interaction. Functional genomics approaches and methods for the manipulation of genes are essential tools for deciphering the roles of genes and to identify new intervention targets in parasites. Exciting advances in functional genomics for parasitic helminths are starting to occur, with transgene expression and RNA interference (RNAi reported in several species of nematodes, but the area is still in its infancy in flatworms, with reports in just three species. While advancing in model organisms, there is a need to rapidly extend these technologies to other parasites responsible for several chronic diseases of humans and cattle. In order to extend these approaches to less well studied parasitic worms, we developed a test method for the presence of a viable RNAi pathway by silencing the exogenous reporter gene, firefly luciferase (fLUC. We established the method in the human blood fluke Schistosoma mansoni and then confirmed its utility in the liver fluke Fasciola hepatica. We transformed newly excysted juveniles of F. hepatica by electroporation with mRNA of fLUC and three hours later were able to detect luciferase enzyme activity, concentrated mainly in the digestive ceca. Subsequently, we tested the presence of an active RNAi pathway in F. hepatica by knocking down the exogenous luciferase activity by introduction into the transformed parasites of double-stranded RNA (dsRNA specific for fLUC. In addition, we tested the RNAi pathway targeting an endogenous F. hepatica gene encoding leucine aminopeptidase (FhLAP, and observed a significant reduction in specific mRNA levels. In summary, these studies demonstrated the utility of RNAi targeting reporter fLUC as a reporter gene assay to establish the presence of an intact RNAi pathway in helminth

Histochemical Study of the Progenetic Trematode Alloglossidium renale

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Craig A. Schimmer

2014-01-01

Full Text Available A histochemical study of the progenetic trematode Alloglossidium renale has demonstrated the absence of any secreted material between the adult worm and the host (freshwater shrimp antennal gland tubules. Host tissue is affected only by the compression, abrasion, and ingestion by the parasite, and host tubule cells near the worm have the same staining patterns as those distant from the parasite. The trematode sometimes dies within the host, leaving a necrotic mass whose histochemical staining differs significantly from the living organism. In the necrotic mass, the only recognizable features were the ova and the vitellarium, which atrophied and resulted in tyrosine-positive staining within the mass. A melanin reaction was not observed in the host using a specialized ferro-ferricyanide stain. The only apparent host response to infection was a layer of damaged squamous host cells adhering to the necrotic worm. The results confirm benign host-parasite effects and a highly evolved relationship between the host and parasite, perhaps bordering on commensalism.

Elucidating the transcriptome of Fasciola hepatica - a key to fundamental and biotechnological discoveries for a neglected parasite.

Science.gov (United States)

Young, Neil D; Hall, Ross S; Jex, Aaron R; Cantacessi, Cinzia; Gasser, Robin B

2010-01-01

Liver flukes of animals are parasitic flatworms (Platyhelminthes: Digenea) of major socioeconomic importance in many countries. Key representatives, such as Fasciola hepatica and F. gigantica, cause "liver fluke disease" (= fascioliasis), which is of major animal health significance worldwide. In particular, F. hepatica is a leading cause of production losses to the livestock (mainly sheep and cattle) and meat industries due to clinical disease, reduced weight gain and milk production, and deaths. This parasite is also a major food-borne pathogen of humans throughout parts of the Middle East, Asia and South America. Currently, there is a significant focus on the development of new approaches for the prevention and control of fascioliasis in livestock. Recent technological advances in genomics and bioinformatics provide unique opportunities for the identification and prevalidation of drug targets and vaccines through a better understanding of the biology of F. hepatica and related species as well as their relationship with their hosts at the molecular level. Surprisingly, despite the widespread socioeconomic impact of fascioliasis, genomic datasets for F. hepatica are scant, limiting the molecular biological research of this parasite. The present article explores specifically the transcriptome of the adult stage of F. hepatica using an integrated genomic-bioinformatic platform. The analysis of the current data reveals numerous molecules of biological relevance, some of which are inferred to be involved in key biological processes or pathways that could serve as targets for new trematocidal drugs or vaccines. Improved insights into the transcriptome of F. hepatica should pave the way for future, comparative analysis of the transcriptomes of other developmental stages of this and related parasites, such as F. gigantica, cancer-causing flatworms (Clonorchis sinensis and Opisthorchis viverrini) and blood flukes (Schistosoma mansoni and S. japonicum). Prediction of the

Reproductive system abnormalities in Schistosoma mansoni adult worms isolated from Nectomys squamipes (Muridae: Sigmodontinae: brightfield and confocal laser scanning microscopy analysis

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Neves Renata Heisler

2003-01-01

Full Text Available Schistosoma mansoni adult worms with genital anomalies isolated from Nectomys squamipes (Muridae: Sigmodontinae were studied by confocal laser scanning microscopy under the reflected mode. One male without testicular lobes (testicular agenesia/anorchism and two females, one with an atrophied ovary and another with 17 uterine eggs, were identified. The absence of testicular lobes occurred in a worm presenting otherwise normal male adult characteristics: tegument, tubercles and a gynaecophoric canal with spines. In both female specimens the digestive tube showed a vacuolated appearance, and the specimen with supernumerary uterine eggs exhibited a developing miracidium and an egg with a formed shell. The area of the ventral sucker was similar in both specimens however the tegument thickness, ovary and vitelline glands of the specimen with the atrophied ovary were smaller than those of the one with supernumerary eggs. These reported anomalies in the reproductive system call attention to the need to improve our understanding of genetic regulation and the possible role of environmental influences upon trematode development.

Diagnostic performance of Schistosoma real-time PCR in urine samples from Kenyan children infected with Schistosoma haematobium

DEFF Research Database (Denmark)

Vinkeles Melchers, Natalie V. S.; van Dam, Govert J.; Shaproski, David

2014-01-01

treatment. METHODOLOGY: Previously collected urine samples (N = 390) from 114 preselected proven parasitological and/or clinical S. haematobium positive Kenyan schoolchildren were analyzed by a Schistosoma internal transcribed spacer-based real-time PCR after 14 years of storage. Pre-treatment day......, respectively. Based on the 'gold standard', PCR showed high sensitivity (>92%) as compared to >31% sensitivity for microscopy, both pre- and post-treatment. CONCLUSIONS/SIGNIFICANCE: Detection and quantification of Schistosoma DNA in urine by real-time PCR was shown to be a powerful and specific diagnostic...

C:\\BACKUP 21.01.2015\\All 5d1a\\BAJOPAS\\Bajopas 8(1)

African Journals Online (AJOL)

User

2015-01-21

Jan 21, 2015 ... organism (the host) and from which it gains it food supply and other means of lively hood Henderson,. (1990), reported that most parasites of intestinal worms are classified as cestodes (Tape worms),. Trematode (flukes) nematodes (round worms) and protozoans. It has been discovered that parasites of ...

Determinants of Schistosoma mansoni in Sanja health center, north West Ethiopia.

Science.gov (United States)

Andargie, Asrat Atsedeweyn; Abera, Agmas Sisay

2018-05-11

In developing countries, Schistosoma mansoni is one of the chronic but neglected tropical diseases. In sub-Saharan Africa, the disease affects over 250 million people with nearly 800 million are at risk. In Ethiopia, Schistosoma mansoni is one of the most prevalent parasitic diseases. The aim of this study was to determine the prevalence and identify the determinant factors of Schistosoma mansoni, in terms of some socio-demographic variables and risk factors. A cross-sectional parasitological survey was conducted at Sanja health center, northwest Ethiopia from June 1 to June 30, 2015. A total of 228 study participants were included in the study. The participants were selected using systematic random sampling technique. Stool specimens were collected and examined using Kato-Katz methods. Structural questionnaires were used to collect data on socio-demographic variables and risk factors by face to face interviews. The major risk factors and demographic determinants of the infection status of Schistosoma mansoni were identified by using descriptive and ordinal logistic regression techniques. The overall prevalence of Schistosoma mansoni was 16.67% (95%CI: 11.83-21.51%). Covariates such as no habit of swimming in rivers has lower risk (AOR = 0.022: 95%CI: 0.011-0.764), no frequency of swimming in rivers (AOR = 0.022: 95%CI: 0.0024-0.207), and 1 to 2 frequency of swimming (OR = 0.302: 95%CI: 0.097-0.941), washing clothes in rivers (AOR = 0.194: 95%CI: 0.046-0.0.811) and bathing in the river (AOR = 0.09: 95%CI: 0.010-0.815) were the most important determinant factors (P-value < 0.5) of Schistosoma mansoni in Sanja health center. In this study, the prevalence of Schistosoma mansoni was found to be high. Swimming habits, frequency of swimming, washing clothes, and bathing in rivers were found to be significant predictors of Schistosoma mansoni. Provisions of a safe water supply in the area and health education about the transmission of the Schistosoma

Detection of major climatic and environmental predictors of liver fluke exposure risk in Ireland using spatial cluster analysis.

Science.gov (United States)

Selemetas, Nikolaos; de Waal, Theo

2015-04-30

Fasciolosis caused by Fasciola hepatica (liver fluke) can cause significant economic and production losses in dairy cow farms. The aim of the current study was to identify important weather and environmental predictors of the exposure risk to liver fluke by detecting clusters of fasciolosis in Ireland. During autumn 2012, bulk-tank milk samples from 4365 dairy farms were collected throughout Ireland. Using an in-house antibody-detection ELISA, the analysis of BTM samples showed that 83% (n=3602) of dairy farms had been exposed to liver fluke. The Getis-Ord Gi* statistic identified 74 high-risk and 130 low-risk significant (Pclimatic variables (monthly and seasonal mean rainfall and temperatures, total wet days and rain days) and environmental datasets (soil types, enhanced vegetation index and normalised difference vegetation index) were used to investigate dissimilarities in the exposure to liver fluke between clusters. Rainfall, total wet days and rain days, and soil type were the significant classes of climatic and environmental variables explaining the differences between significant clusters. A discriminant function analysis was used to predict the exposure risk to liver fluke using 80% of data for modelling and the remaining subset of 20% for post hoc model validation. The most significant predictors of the model risk function were total rainfall in August and September and total wet days. The risk model presented 100% sensitivity and 91% specificity and an accuracy of 95% correctly classified cases. A risk map of exposure to liver fluke was constructed with higher probability of exposure in western and north-western regions. The results of this study identified differences between clusters of fasciolosis in Ireland regarding climatic and environmental variables and detected significant predictors of the exposure risk to liver fluke. Copyright © 2015 Elsevier B.V. All rights reserved.

Whole genome analysis of a schistosomiasis-transmitting freshwater snail

NARCIS (Netherlands)

Adema, Coen M; Hillier, LaDeana W; Jones, Catherine S; Loker, Eric S; Knight, Matty; Minx, Patrick; Oliveira, Guilherme; Raghavan, Nithya; Shedlock, Andrew; do Amaral, Laurence Rodrigues; Arican-Goktas, Halime D; Assis, Juliana G; Baba, Elio Hideo; Baron, Olga L; Bayne, Christopher J; Bickham-Wright, Utibe; Biggar, Kyle K; Blouin, Michael; Bonning, Bryony C; Botka, Chris; Bridger, Joanna M; Buckley, Katherine M; Buddenborg, Sarah K; Lima Caldeira, Roberta; Carleton, Julia; Carvalho, Omar S; Castillo, Maria G; Chalmers, Iain W; Christensens, Mikkel; Clifton, Sandra; Cosseau, Celine; Coustau, Christine; Cripps, Richard M; Cuesta-Astroz, Yesid; Cummins, Scott F; di Stephano, Leon; Dinguirard, Nathalie; Duval, David; Emrich, Scott; Feschotte, Cédric; Feyereisen, Rene; FitzGerald, Peter; Fronick, Catrina; Fulton, Lucinda; Galinier, Richard; Gava, Sandra G; Geusz, Michael; Geyer, Kathrin K; Giraldo-Calderón, Gloria I; de Souza Gomes, Matheus; Gordy, Michelle A; Gourbal, Benjamin; Grunau, Christoph; Hanington, Patrick C; Hoffmann, Karl F; Hughes, Daniel; Humphries, Judith; Jackson, Daniel J; Jannotti-Passos, Liana K; de Jesus Jeremias, Wander; Jobling, Susan; Kamel, Bishoy; Kapusta, Aurélie; Kaur, Satwant; Koene, Joris M; Kohn, Andrea B; Lawson, Dan; Lawton, Scott P; Liang, D.C.; Limpanont, Yanin; Liu, Sijun; Lockyer, Anne E; Lovato, TyAnna L; Ludolf, Fernanda; Magrini, Vince; McManus, Donald P; Medina, Monica; Misra, Milind; Mitta, Guillaume; Mkoji, Gerald M; Montague, Michael J; Montelongo, Cesar; Moroz, Leonid L; Munoz-Torres, Monica C; Niazi, Umar; Noble, Leslie R; Oliveira, Francislon S; Pais, Fabiano S; Papenfuss, Anthony T; Peace, Rob; Pena, Janeth J; Pila, Emmanuel A; Quelais, Titouan; Raney, Brian J; Rast, Jonathan P; Rollinson, David; Rosse, Izinara C; Rotgans, Bronwyn; Routledge, Edwin J; Ryan, Kathryn M; Scholte, Larissa L S; Storey, Kenneth B; Swain, Martin; Tennessen, Jacob A; Tomlinson, Chad; Trujillo, Damian L; Volpi, Emanuela V; Walker, Anthony J; Wang, Tianfang; Wannaporn, Ittiprasert; Warren, Wesley C; Wu, Xiao-Jun; Yoshino, Timothy P; Yusuf, Mohammed; Zhang, Si-Ming; Zhao, Min; Wilson, Richard K

2017-01-01

Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of

New location for Bulinus truncatus (Audouin, 1827 (Gastropoda: Planorbidae intermediate host of Schistosoma haematobium and its distribution in the Iberian Peninsula

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Dana, Elías D.

2015-12-01

Full Text Available This paper reports a new population of Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae found in the province of Almería (Southeast Spain. B. truncatus is an intermediate host of Schistosoma haematobium, the trematode which causes urinary schistosomiasis in humans. Individuals were identified to species level by double-nested PCR, resulting in 100% homology. This population is located under the driest climate conditions of the Iberian Peninsula. Data on the distribution of this species in the Iberian Peninsula was gathered and is provided in this paper. Improved knowledge of the distribution of Bulinus truncatus is key to assess the risk of new outbreaks of schistosomiasis in the Iberian Peninsula.En este trabajo se reporta una nueva población de Bulinus truncatus (Audouin, 1827 (Gastropoda, Planorbidae en la provincia de Almería (Sureste de España. Se trata de una especie que presenta considerable interés tanto zoológico como epidemiológico por su papel como hospedador intermediario de Schistosoma haematobium, responsable de la esquistosomiasis urogenital humana. Los ejemplares fueron determinados a nivel específico mediante PCR doble anidada, con un 100% de homología. Se trata de la población localizada más al Sureste y en condiciones de mayor aridez en la península Ibérica. Se recopilaron los datos de presencia publicados para conocer su distribución en la península. El conocimiento de la distribución de Bulinus truncatus es una pieza clave para evaluar el riesgo de nuevos focos de esquistosomiasis en la península Ibérica.

Trematode communities in snails can indicate impact and recovery from hurricanes in a tropical coastal lagoon.

Science.gov (United States)

Aguirre-Macedo, María Leopoldina; Vidal-Martínez, Victor M; Lafferty, Kevin D

2011-11-01

In September 2002, Hurricane Isidore devastated the Yucatán Peninsula, Mexico. To understand its effects on the parasites of aquatic organisms, we analyzed long-term monthly population data of the horn snail Cerithidea pliculosa and its trematode communities in Celestún, Yucatán, Mexico before and after the hurricane (February 2001 to December 2009). Five trematode species occurred in the snail population: Mesostephanus appendiculatoides, Euhaplorchis californiensis, two species of the genus Renicola and one Heterophyidae gen. sp. Because these parasites use snails as first intermediate hosts, fishes as second intermediate hosts and birds as final hosts, their presence in snails depends on food webs. No snails were present at the sampled sites for 6 months after the hurricane. After snails recolonised the site, no trematodes were found in snails until 14 months after the hurricane. It took several years for snail and trematode populations to recover. Our results suggest that the increase in the occurrence of hurricanes predicted due to climate change can impact upon parasites with complex life cycles. However, both the snail populations and their parasite communities eventually reached numbers of individuals and species similar to those before the hurricane. Thus, the trematode parasites of snails can be useful indicators of coastal lagoon ecosystem degradation and recovery. Copyright © 2011 Australian Society for Parasitology Inc. All rights reserved.

Fibrinogen and fibrin are novel substrates for Fasciola hepatica cathepsin L peptidases

NARCIS (Netherlands)

Mebius, Mirjam M.; Op Heij, Jody M J; Tielens, Aloysius G.M.; de Groot, Philip G; Urbanus, Rolf T; van Hellemond, Jaap J.

2018-01-01

Cathepsin peptidases form a major component of the secreted proteins of the blood-feeding trematodes Fasciola hepatica and Schistosoma mansoni. These peptidases fulfill many functions, from facilitating infection to feeding and immune evasion. In this study, we examined the Fasciola cathepsin L

Prevalence and Sequence-Based Identity of Rumen Fluke in Cattle and Deer in New Caledonia.

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Laura Cauquil

Full Text Available An abattoir survey was performed in the French Melanesian archipelago of New Caledonia to determine the prevalence of paramphistomes in cattle and deer and to generate material for molecular typing at species and subspecies level. Prevalence in adult cattle was high at animal level (70% of 387 adult cattle and batch level (81%. Prevalence was lower in calves at both levels (33% of 484 calves, 51% at batch level. Animals from 2 of 7 deer farms were positive for rumen fluke, with animal-level prevalence of 41.4% (29/70 and 47.1% (33/70, respectively. Using ITS-2 sequencing, 3 species of paramphistomes were identified, i.e. Calicophoron calicophorum, Fischoederius elongatus and Orthocoelium streptocoelium. All three species were detected in cattle as well as deer, suggesting the possibility of rumen fluke transmission between the two host species. Based on heterogeneity in ITS-2 sequences, the C. calicophorum population comprises two clades, both of which occur in cattle as well as deer. The results suggest two distinct routes of rumen fluke introduction into this area. This approach has wider applicability for investigations of the origin of rumen fluke infections and for the possibility of parasite transmission at the livestock-wildlife interface.

Trematodes in snails near raccoon latrines suggest a final host role for this mammal in California Salt Marshes

Science.gov (United States)

Lafferty, K.D.; Dunham, E.J.

2005-01-01

Of the 18 trematode species that use the horn snail, Cerithidea californica, as a first intermediate host, 6 have the potential to use raccoons as a final host. The presence of raccoon latrines in Carpinteria Salt Marsh, California, allowed us to investigate associations between raccoons and trematodes in snails. Two trematode species, Probolocoryphe uca and Stictodora hancocki, occurred at higher prevalences in snails near raccoon latrines than in snails away from latrines, suggesting that raccoons may serve as final hosts for these species. Fecal remains indicated that raccoons fed on shore crabs, the second intermediate host for P. uca, and fish, the second intermediate host for S. hancocki. The increase in raccoon populations in the suburban areas surrounding west coast salt marshes could increase their importance as final hosts for trematodes in this system. ?? American Society of Parasitologists 2005.

Whole genome analysis of a schistosomiasis-transmitting freshwater snail

DEFF Research Database (Denmark)

Adema, Coen M; Hillier, Ladeana W; Jones, Catherine S

2017-01-01

Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biompha...

CT manifestation of schistosoma haematobium cystitis

International Nuclear Information System (INIS)

Wang Yujun; Hu Lirong; Cheng Yougen; Mao Guoqun; Yang Guangzhao; Modya Camara; Mohamed Traore

2014-01-01

Objective: To analyze CT manifestation of Schistosoma haematobium cystitis. Methods: Retrospective analysis 32 patients, who were tested for Schistosoma haematobium cystitis using the urine filtration method. CT scan was performed for each patient with contrast enhancement. Results: The vast majority of urinary tract schistomiasis lesions were in the urinary bladder. Calcification of the bladder wall was observed in all patients and mild enhancement in non calcified zone was found after intravenous contrast. Except for 5 patients of bladder cancer, the rest were no abnormality in size of bladder when bladder was filling or emptying. Ureteral wall annular calcification could also be identified in 25 patients. Twenty two patients were companied with ureteric hydronephrosis. Seminal vesicle calcification was seen in 4 patients among 11 male patients, while both uterine and ovarian in female and prostate in men had non calcification. Serious illness can be combined with bladder cancer. In 5 patients of patients with bladder cancer, bladder showed irregular soft tissue mass which was enhanced moderately after post-contrast scan, with vesical calcification in mass medially. Conclusion: Bladder calcification is the most prominent CT feature of Schistosoma haematobium cystitis, which is useful in diagnosis the disease. (authors)

[Molecular genetic characterization of the Far Eastern trematode Skrjabino lecithum spasskii Belous, 1954 (Digenea: Haploporidae)), a parasite of mullets].

Science.gov (United States)

Atopkin, D M; Nikitenko, A Yu; Ngo, H D; Ha, N V; Tang, N V

2015-01-01

Intraspecific genetic differentiation of the trematode Skrjabinolecithum spasskii and its phylogenetic relationships with other species of the family Haploporidae were studied by comparing the nucleotide sequences of a part of the 28S rRNA gene and the ITS1-5.8S-ITS2 rDNA region. Trematodes were isolated from so-iuy mullet Liza haematocheila fishes collected in rivers of Primorye and flathead grey mullet Mugil cephalus fishes collected in water bodies of Vietnam (27 fishes in total). A phylogenetic analysis showed that S. spasskii is close to species of the genus Capitimitta of the subfamily Waretrematinae. By intraspecific variation of rDNA sequences, trematodes were divided into three groups with tree different genotypes, which had fixed nucleotide substitutions. Genotype I was found in trematodes from fishes collected in Primorye. Genotype II was detected in trematodes from M. cephalus fishes collected in the Tonkin Bay, Cat Ba Island, Vietnam. Genotype III was found in five trematodes from L. haematocheila collected in the Kievka River, Primorye. The genetic distances between genotypes I and III from Primorye were 0.4 and 0.65% by 28S and ITS rDNA sequences, respectively. The lowest genetic distances were observed between genotypes II (Vietnam) and III (Primorye), 0.1 and 0.33% by 28S and ITS rDNA sequences, respectively. Possible causes of genetic differentiation of S. spasskii from different geographic locations and different definitive host species are discussed.

Praziquantel treatment decreases Schistosoma mansoni genetic diversity in experimental infections.

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Regina Coeli

Full Text Available BACKGROUND: Schistosomiasis has a considerable impact on public health in many tropical and subtropical areas. In the new world, schistosomiasis is caused by the digenetic trematode Schistosoma mansoni. Chemotherapy is the main measure for controlling schistosomiasis, and the current drug of choice for treatment is praziquantel (PZQ. Although PZQ is efficient and safe, its repetitive large-scale use in endemic areas may lead to the selection of resistant strains. Isolates less susceptible to PZQ have been found in the field and selected for in the laboratory. The impact of selecting strains with a decreased susceptibility phenotype on disease dynamics and parasite population genetics is not fully understood. This study addresses the impact of PZQ pressure on the genetics of a laboratory population by analyzing frequency variations of polymorphic genetic markers. METHODOLOGY: Infected mice were treated with increasing PZQ doses until the highest dose of 3 × 300 mg/Kg was reached. The effect of PZQ treatment on the parasite population was assessed using five polymorphic microsatellite markers. Parasitological and genetic data were compared with those of the untreated control. After six parasite generations submitted to treatment, it was possible to obtain a S. mansoni population with decreased susceptibility to PZQ. In our experiments we also observed that female worms were more susceptible to PZQ than male worms. CONCLUSIONS: The selective pressure exerted by PZQ led to decreased genetic variability in S. mansoni and increased endogamy. The understanding of how S. mansoni populations respond to successive drug pressure has important implications on the appearance and maintenance of a PZQ resistance phenotype in endemic regions.

Effect of praziquantel on the differential expression of mouse hepatic genes and parasite ATP binding cassette transporter gene family members during Schistosoma mansoni infection.

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Melissa C Sanchez

2017-06-01

Full Text Available Schistosomiasis is a chronic parasitic disease caused by sexually dimorphic blood flukes of the genus Schistosoma. Praziquantel (PZQ is the only drug widely available to treat the disease but does not kill juvenile parasites. Here we report the use of next generation sequencing to study the transcriptional effect of PZQ on murine hepatic inflammatory, immune and fibrotic responses to Schistosoma mansoni worms and eggs. An initial T helper cell 1 (Th1 response is induced against schistosomes in mice treated with drug vehicle (Vh around the time egg laying begins, followed by a T helper cell 2 (Th2 response and the induction of genes whose action leads to granuloma formation and fibrosis. When PZQ is administered at this time, there is a significant reduction in egg burden yet the hepatic Th1, Th2 and fibrotic responses are still observed in the absence of granuloma formation suggesting some degree of gene regulation may be induced by antigens released from the dying adult worms. Quantitative real-time PCR was used to examine the relative expression of 16 juvenile and adult S. mansoni genes during infection and their response to Vh and PZQ treatment in vivo. While the response of stress genes in adult parasites suggests the worms were alive immediately following exposure to PZQ, they were unable to induce transcription of any of the 9 genes encoding ATP-binding cassette (ABC transporters tested. In contrast, juvenile schistosomes were able to significantly induce the activities of ABCB, C and G family members, underscoring the possibility that these efflux systems play a major role in drug resistance.

Prevalence, risk factors and spatial analysis of infections with liver flukes in Danish cattle herds

DEFF Research Database (Denmark)

Hisham Beshara Halasa, Tariq; Frankena, K.; Olsen, A.

Liver fluke infection, also known as fasciolosis, is a world-wide prevalent zoonotic parasitic disease infecting a wide range of host species and is caused by Fasciola hepatica. Despite of the substantial economic and animal welfare effects of the disease, knowledge on its prevalence and the fact......Liver fluke infection, also known as fasciolosis, is a world-wide prevalent zoonotic parasitic disease infecting a wide range of host species and is caused by Fasciola hepatica. Despite of the substantial economic and animal welfare effects of the disease, knowledge on its prevalence...

Development of a real time polymerase chain reaction for quantitation of Schistosoma mansoni DNA

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Ana Lisa do Vale Gomes

2006-10-01

Full Text Available This report describes the development of a SYBR Green I based real time polymerase chain reaction (PCR protocol for detection on the ABI Prism 7000 instrument. Primers targeting the gene encoding the SSU rRNA were designed to amplify with high specificity DNA from Schistosoma mansoni, in a real time quantitative PCR system. The limit of detection of parasite DNA for the system was 10 fg of purified genomic DNA, that means less than the equivalent to one parasite cell (genome ~580 fg DNA. The efficiency was 0.99 and the correlation coefficient (R² was 0.97. When different copy numbers of the target amplicon were used as standards, the assay could detect at least 10 copies of the specific target. The primers used were designed to amplify a 106 bp DNA fragment (Tm 83ºC. The assay was highly specific for S. mansoni, and did not recognize DNA from closely related non-schistosome trematodes. The real time PCR allowed for accurate quantification of S. mansoni DNA and no time-consuming post-PCR detection of amplification products by gel electrophoresis was required. The assay is potentially able to quantify S. mansoni DNA (and indirectly parasite burden in a number of samples, such as snail tissue, serum and feces from patients, and cercaria infested water. Thus, these PCR protocols have potential to be used as tools for monitoring of schistosome transmission and quantitative diagnosis of human infection.

In vitro uptake of 14C-praziquantel by cestodes, trematodes, and a nematode

International Nuclear Information System (INIS)

Andrews, P.; Thomas, H.; Weber, H.

1980-01-01

14 C-praziquantel was rapidly taken up by Schistosoma mansoni, Fasciola hepatica, Hymenolepis nana, and isolated strobilocerci of Taenia taeniaeformis. Schistosoma mansoni lost praziquantel rapidly to drug-free medium. Chromatography of extracts prepared after incubation of S. mansoni and H. nana yielded no indication that praziquantel was metabolized. Autoradiography revealed a uniform distribution of praziquantel throughout the tissues of S. mansoni and H. nana. Uptake was considerably slower in the nematode Heterakis spumosa and apparently via the oral route

Helminths and malignancy

DEFF Research Database (Denmark)

Vennervald, Birgitte J; Polman, K.

2009-01-01

-malignant change has taken place. Three helminth infections have been classified as definitely carcinogenic to humans (group 1 carcinogens), namely Schistosoma haematobium, which is associated with cancer of the urinary bladder and the food-borne liver flukes Clonorchis sinensis and Opisthorchis viverrini......It has been estimated that chronic infections with viruses, bacteria and parasites contribute to 17.8% of the global burden of cancer, although only a relatively small proportion of the infection-related cancers can be attributed to helminth infections. These are important because of the high...... coupled with health education, especially in relation to food-borne liver fluke infections....

A directed approach for the identification of transcripts harbouring the spliced leader sequence and the effect of trans-splicing knockdown in Schistosoma mansoni

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Marina de Moraes Mourao

2013-09-01

Full Text Available Schistosomiasis is a major neglected tropical disease caused by trematodes from the genus Schistosoma. Because schistosomes exhibit a complex life cycle and numerous mechanisms for regulating gene expression, it is believed that spliced leader (SL trans-splicing could play an important role in the biology of these parasites. The purpose of this study was to investigate the function of trans-splicing in Schistosoma mansoni through analysis of genes that may be regulated by this mechanism and via silencing SL-containing transcripts through RNA interference. Here, we report our analysis of SL transcript-enriched cDNA libraries from different S. mansoni life stages. Our results show that the trans-splicing mechanism is apparently not associated with specific genes, subcellular localisations or life stages. In cross-species comparisons, even though the sets of genes that are subject to SL trans-splicing regulation appear to differ between organisms, several commonly shared orthologues were observed. Knockdown of trans-spliced transcripts in sporocysts resulted in a systemic reduction of the expression levels of all tested trans-spliced transcripts; however, the only phenotypic effect observed was diminished larval size. Further studies involving the findings from this work will provide new insights into the role of trans-splicing in the biology of S. mansoni and other organisms. All Expressed Sequence Tags generated in this study were submitted to dbEST as five different libraries. The accessions for each library and for the individual sequences are as follows: (i adult worms of mixed sexes (LIBEST_027999: JZ139310 - JZ139779, (ii female adult worms (LIBEST_028000: JZ139780 - JZ140379, (iii male adult worms (LIBEST_028001: JZ140380 - JZ141002, (iv eggs (LIBEST_028002: JZ141003 - JZ141497 and (v schistosomula (LIBEST_028003: JZ141498 - JZ141974.

High reinfection rate after preventive chemotherapy for fishborne zoonotic trematodes in Vietnam

DEFF Research Database (Denmark)

Lier, Tore; Do, Dung Trung; Johansen, Maria Vang

2014-01-01

. The purpose of this study was to investigate the effectiveness of preventive chemotherapy to control FZT in an endemic area in Northern Vietnam. METHODOLOGY AND PRINCIPLE FINDINGS: We followed a cohort of 396 people who fulfilled the criteria for receiving preventive chemotherapy. Stool samples were examined....... CONCLUSIONS: The effectiveness of preventive chemotherapy as a main component in control of FZT is not well documented in most endemic areas. We found a high reinfection rate within the first year after preventive chemotherapy. Since these trematodes are zoonoses, preventive chemotherapy may not have......BACKGROUND: The World Health Organization aims for complete morbidity control of fishborne zoonotic trematodes (FZT) in endemic areas by 2020. The main intervention tool for achieving this goal is regular use of preventive chemotherapy by offering praziquantel to those at risk in endemic areas...

Effect of fish size on transmission of fish-borne trematodes (Heterophyidae) to common carps (Cyprinus carpio) and implications for intervention

NARCIS (Netherlands)

Boerlage, A.S.; Graat, E.A.M.; Verreth, J.A.J.; Jong, de M.C.M.

2011-01-01

Fish-borne trematodes are reported to affect the health of more than 40 million people worldwide. Few experimental studies are available on fish size dependent gain (attack rates of cercariae) or loss (mortality of metacercariae) of fish-borne trematodes. Aim was to quantify the relation between

Granulin Secreted by the Food-Borne Liver Fluke Opisthorchis viverrini Promotes Angiogenesis in Human Endothelial Cells

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Brandon Haugen

2018-02-01

Full Text Available The liver fluke Opisthorchis viverrini is a food-borne, zoonotic pathogen endemic to Thailand and adjacent countries in Southeast Asia. The adult developmental stage of the O. viverrini parasite excretes and secretes numerous proteins within the biliary tract including the gall bladder. Lesions caused by the feeding activities of the liver fluke represent wounds that undergo protracted cycles of healing and re-injury during chronic infection, which can last for decades. Components of the excretory/secretory (ES complement released by the worms capably drive proliferation of bile duct epithelial cells and are implicated in establishing the oncogenic milieu that leads to bile duct cancer, cholangiocarcinoma. An ES protein, the secreted granulin-like growth factor termed Ov-GRN-1, accelerates wound resolution in mice and in vitro. To investigate angiogenesis (blood vessel development that may contribute to wound healing promoted by liver fluke granulin and, by implication, to carcinogenesis during chronic opisthorchiasis, we employed an in vitro tubule formation assay (TFA where human umbilical vein endothelial cells were grown on gelled basement matrix. Ten and 40 nM Ov-GRN-1 significantly stimulated angiogenesis as monitored by cellular proliferation and by TFA in real time. This demonstration of potent angiogenic property of Ov-GRN-1 bolsters earlier reports on the therapeutic potential for chronic non-healing wounds of diabetics, tobacco users, and the elderly and, in addition, showcases another of the hallmark of cancer characteristic of this carcinogenic liver fluke.

Effects of dietary intake of garlic on intestinal trematodes.

Science.gov (United States)

Cortés, Alba; García-Ferrús, Miguel; Sotillo, Javier; Guillermo Esteban, J; Toledo, Rafael; Muñoz-Antolí, Carla

2017-08-01

The current strategy for the control of helminth infections relies on chemotherapy. However, resistance appearance is promoting the necessity of developing new drugs against trematodes. Herein, potential trematocidal effects of garlic (Allium sativum) are investigated in the context of intestinal foodborne trematodes, employing the Echinostoma caproni-mouse model. Daily administration of dietary doses of garlic was conducted in three groups of mice: (i) before infection (prophylaxis), (ii) after infection (therapeutic) and (iii) both, before and after infection (continuous). A fourth group of mice, not exposed to garlic, was used as control. No differences in worm recovery, fecundity and local cytokine expression profiles were found with respect to control infections. However, considerable alterations in tegument structure, including swelling, furrowing, vacuolization and changes in secretory bodies were detected in garlic-exposed parasites using scanning and transmission electron microscopy. Protein secretion was markedly reduced in response to garlic, whereas up-regulation of several proteins, such as major vault protein and tER-ATPase, was observed in treated worms. The results presented herein provide new insights in the anthelminthic activity of bioactive garlic compounds and the manner that parasites respond to toxins.

RNAi dynamics in Juvenile Fasciola spp. Liver flukes reveals the persistence of gene silencing in vitro.

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Paul McVeigh

2014-09-01

Full Text Available Fasciola spp. liver fluke cause pernicious disease in humans and animals. Whilst current control is unsustainable due to anthelmintic resistance, gene silencing (RNA interference, RNAi has the potential to contribute to functional validation of new therapeutic targets. The susceptibility of juvenile Fasciola hepatica to double stranded (dsRNA-induced RNAi has been reported. To exploit this we probe RNAi dynamics, penetrance and persistence with the aim of building a robust platform for reverse genetics in liver fluke. We describe development of standardised RNAi protocols for a commercially-available liver fluke strain (the US Pacific North West Wild Strain, validated via robust transcriptional silencing of seven virulence genes, with in-depth experimental optimisation of three: cathepsin L (FheCatL and B (FheCatB cysteine proteases, and a σ-class glutathione transferase (FheσGST.Robust transcriptional silencing of targets in both F. hepatica and Fasciola gigantica juveniles is achievable following exposure to long (200-320 nt dsRNAs or 27 nt short interfering (siRNAs. Although juveniles are highly RNAi-susceptible, they display slower transcript and protein knockdown dynamics than those reported previously. Knockdown was detectable following as little as 4h exposure to trigger (target-dependent and in all cases silencing persisted for ≥25 days following long dsRNA exposure. Combinatorial silencing of three targets by mixing multiple long dsRNAs was similarly efficient. Despite profound transcriptional suppression, we found a significant time-lag before the occurrence of protein suppression; FheσGST and FheCatL protein suppression were only detectable after 9 and 21 days, respectively.In spite of marked variation in knockdown dynamics, we find that a transient exposure to long dsRNA or siRNA triggers robust RNAi penetrance and persistence in liver fluke NEJs supporting the development of multiple-throughput phenotypic screens for control

Identification of the Schistosoma mansoni Molecular Target for the Antimalarial Drug Artemether

KAUST Repository

Lepore, Rosalba

2011-11-28

Plasmodium falciparum and Schistosoma mansonii are the parasites responsible for most of the malaria and schistosomiasis cases in the world. Notwithstanding their many differences, the two agents have striking similarities in that they both are blood feeders and are targets of an overlapping set of drugs, including the well-known artemether molecule. Here we explore the possibility of using the known information about the mode of action of artemether in Plasmodium to identify the molecular target of the drug in Schistosoma and provide evidence that artemether binds to SmSERCA, a putative Ca2+-ATPase of Schistosoma. We also predict the putative binding mode of the molecule for both its Plasmodium and Schistosoma targets. Our analysis of the mode of binding of artemether to Ca2+-ATPases also provides an explanation for the apparent paradox that, although the molecule has no side effect in humans, it has been shown to possess antitumoral activity. © 2011 American Chemical Society.

Identification and characterization of argonaute protein, Ago2 and its associated small RNAs in Schistosoma japonicum.

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Pengfei Cai

Full Text Available BACKGROUND: The complex life cycle of the genus Schistosoma drives the parasites to employ subtle developmentally dependent gene regulatory machineries. Small non-coding RNAs (sncRNAs are essential gene regulatory factors that, through their impact on mRNA and genome stability, control stage-specific gene expression. Abundant sncRNAs have been identified in this genus. However, their functionally associated partners, Argonaute family proteins, which are the key components of the RNA-induced silencing complex (RISC, have not yet been fully explored. METHODOLOGY/PRINCIPAL FINDINGS: Two monoclonal antibodies (mAbs specific to Schistosoma japonicum Argonaute protein Ago2 (SjAgo2, but not SjAgo1 and SjAgo3, were generated. Soluble adult worm antigen preparation (SWAP was subjected to immunoprecipitation with the mAbs and the captured SjAgo2 protein was subsequently confirmed by Western blot and mass spectrometry (MS analysis. The small RNA population associated with native SjAgo2 in adult parasites was extracted from the immunoprecipitated complex and subjected to library construction. High-through-put sequencing of these libraries yielded a total of ≈50 million high-quality reads. Classification of these small RNAs showed that endogenous siRNAs (endo-siRNAs generated from transposable elements (TEs, especially from the subclasses of LINE and LTR, were prominent. Further bioinformatics analysis revealed that siRNAs derived from ten types of well-defined retrotransposons were dramatically enriched in the SjAgo2-specific libraries compared to small RNA libraries constructed with total small RNAs from separated adult worms. These results suggest that a key function of SjAgo2 is to maintain genome stability through suppressing the activities of retrotransposons. CONCLUSIONS/SIGNIFICANCE: In this study, we identified and characterized one of the three S. japonicum Argonautes, SjAgo2, and its associated small RNAs were found to be predominantly derived

Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China

DEFF Research Database (Denmark)

Li, Kang; Clausen, Jesper Hedegaard; Murrell, Kenneth Darwin

2013-01-01

Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia...... aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1...... for tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level....

Larval trematode infections in freshwater gastropods from the Albufera Natural Park in Spain.

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Toledo, R; Muñoz-Antolí, C; Pérez, M; Esteban, J G

1998-03-01

Malacological samplings were made from January 1994 to December 1996 in the Albufera Natural Park (Valencia, Spain) to trace the dynamics of molluscan populations and the prevalence and intensity of infection by larval trematodes. A total of 10,533 freshwater gastropods belonging to seven species (Lymnaea auricularia, L. truncatula, L. palustris, L. peregra, Bithynia tentaculata, Physa acuta and Gyraulus chinensis) was examined, and 110 (1.04%) were found to harbour some of the nine distinguishable types of cercariae, namely four echinostome cercariae (Hypoderaeum conoideum, Echinoparyphium recurvatum, Euparyphium albuferensis, and Echinostoma sp.), four furcocercous cercariae, and one xiphidiocercous cercaria. This study shows that the composition of the snail and trematode communities may be determined by the particular environmental conditions present and the human intervention in the area.

Emergence of the Zoonotic Biliary Trematode Pseudamphistomum truncatum in Grey Seals (Halichoerus grypus) in the Baltic Sea

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Bergman, Anders; Bignert, Anders; Höglund, Johan; Lundström, Karl; Strömberg, Annika; Bäcklin, Britt-Marie

2016-01-01

The biliary trematode Pseudamphistomum truncatum parasitizes a wide range of fish-eating mammals, including humans. Here we report the emergence of this parasite in grey seals (Halichoerus grypus) in the Baltic Sea. One hundred eighty-three of 1 554 grey seals (11.9%) examined from 2002–2013 had detectable hepatobiliary trematode infection. Parasite identification was confirmed as P. truncatum by sequencing the ITS2 region of a pool of five to 10 trematodes from each of ten seals collected off the coast of seven different Swedish counties. The proportion of seals parasitized by P. truncatum increased significantly over time and with increasing age of seals. Males were 3.1 times more likely to be parasitized than females and animals killed in fishery interactions were less likely to be parasitized than animals found dead or hunted. There was no significant difference in parasitism of seals examined from the Gulf of Bothnia versus those examined from the Baltic Proper. Although the majority of infections were mild, P. truncatum can cause severe hepatobiliary disease and resulted in liver failure in at least one seal. Because cyprinid fish are the second intermediate host for opisthorchiid trematodes, diets of grey seals from the Baltic Sea were analysed regarding presence of cyprinids. The proportion of gastrointestinal tracts containing cyprinid remains was ten times higher in seals examined from 2008 to 2013 (12.2%) than those examined from 2002 to 2007 (1.2%) and coincided with a general increase of trematode parasitism in the host population. The emergence and relatively common occurrence of P. truncatum in grey seals signals the presence of this parasite in the Baltic Sea ecosystem and demonstrates how aquatic mammals can serve as excellent sentinels of marine ecosystem change. Investigation of drivers behind P. truncatum emergence and infection risk for other mammals, including humans, is highly warranted. PMID:27755567

Emergence of the Zoonotic Biliary Trematode Pseudamphistomum truncatum in Grey Seals (Halichoerus grypus in the Baltic Sea.

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Aleksija S Neimanis

Full Text Available The biliary trematode Pseudamphistomum truncatum parasitizes a wide range of fish-eating mammals, including humans. Here we report the emergence of this parasite in grey seals (Halichoerus grypus in the Baltic Sea. One hundred eighty-three of 1 554 grey seals (11.9% examined from 2002-2013 had detectable hepatobiliary trematode infection. Parasite identification was confirmed as P. truncatum by sequencing the ITS2 region of a pool of five to 10 trematodes from each of ten seals collected off the coast of seven different Swedish counties. The proportion of seals parasitized by P. truncatum increased significantly over time and with increasing age of seals. Males were 3.1 times more likely to be parasitized than females and animals killed in fishery interactions were less likely to be parasitized than animals found dead or hunted. There was no significant difference in parasitism of seals examined from the Gulf of Bothnia versus those examined from the Baltic Proper. Although the majority of infections were mild, P. truncatum can cause severe hepatobiliary disease and resulted in liver failure in at least one seal. Because cyprinid fish are the second intermediate host for opisthorchiid trematodes, diets of grey seals from the Baltic Sea were analysed regarding presence of cyprinids. The proportion of gastrointestinal tracts containing cyprinid remains was ten times higher in seals examined from 2008 to 2013 (12.2% than those examined from 2002 to 2007 (1.2% and coincided with a general increase of trematode parasitism in the host population. The emergence and relatively common occurrence of P. truncatum in grey seals signals the presence of this parasite in the Baltic Sea ecosystem and demonstrates how aquatic mammals can serve as excellent sentinels of marine ecosystem change. Investigation of drivers behind P. truncatum emergence and infection risk for other mammals, including humans, is highly warranted.

Ionotropic Receptors Identified within the Tentacle of the Freshwater Snail Biomphalaria glabrata, an Intermediate Host of Schistosoma mansoni.

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Di Liang

Full Text Available Biomphalaria glabrata (B. glabrata is an air-breathing aquatic mollusc found in freshwater habitats across the Western Hemisphere. It is most well-known for its recognized capacity to act as a major intermediate host for Schistosoma mansoni, the human blood fluke parasite. Ionotropic receptors (IRs, a variant family of the ionotropic glutamate receptors (iGluR, have an evolutionary ancient function in detecting odors to initiate chemosensory signaling. In this study, we applied an array of methods towards the goal of identifying IR-like family members in B. glabrata, ultimately revealing two types, the iGluR and IR. Sequence alignment showed that three ligand-binding residues are conserved in most Biomphalaria iGluR sequences, while the IRs did exhibit a variable pattern, lacking some or all known glutamate-interactingresidues, supporting their distinct classification from the iGluRs. We show that B. glabrata contains 7 putative IRs, some of which are expressed within its chemosensory organs. To further investigate a role for the more ancient IR25a type in chemoreception, we tested its spatial distribution pattern within the snail cephalic tentacle by in situ hybridization. The presence of IR25a within presumptive sensory neurons supports a role for this receptor in olfactory processing, contributing to our understanding of the molecular pathways that are involved in Biomphalaria olfactory processing.

Behavioural plasticity of social trematodes depends upon social context

OpenAIRE

Kamiya, T.; Poulin, R.

2013-01-01

Members of some social insects adjust their behaviours depending upon social context. Such plasticity allows colonies to sustain efficiency of the whole without the cost of additional production of individuals or delayed responses to perturbations. Using the recently discovered social clonal stage of trematode parasites, we investigated whether members of the reproductive caste adjust their defensive behaviour according to the local availability of non-reproductive defensive specialists, and ...

Anthelmintic Activity of Crude Extract and Essential Oil of Tanacetum vulgare (Asteraceae against Adult Worms of Schistosoma mansoni

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Loyana Silva Godinho

2014-01-01

Full Text Available Schistosomiasis, a parasitic disease caused by trematode flatworms of the genus Schistosoma, affects more than 200 million people worldwide, and its control is dependent on a single drug, praziquantel. Tanacetum vulgare (Asteraceae is used in folk medicine as a vermifuge. This study aimed to investigate the in vitro schistosomicidal activity of the crude extract (TV and the essential oil (TV-EO from the aerial parts of T. vulgare. TV-EO was obtained by hydrodistillation and analyzed by GC/MS, which allowed the identification of β-thujone (84.13% as the major constituent. TV and TV-EO, at 200 μg/mL, decreased motor activity and caused 100% mortality of all adult worms. At 100 and 50 μg/mL, only TV caused death of all adult worms, while TV-EO was inactive. TV (200 μg/mL was also able to reduce viability and decrease production of developed eggs. Confocal laser scanning microscopy showed morphological alterations in the tegument of the S. mansoni surface after incubation with TV (50 and 100 μg/mL. Quantitative analysis on the schistosomes tegument showed that TV caused changes in the numbers of tubercles of S. mansoni male worms in a dose-dependent manner. The findings suggest that T. vulgare is a potential source of schistosomicidal compounds.

Prevalence of Snail Vectors of Schistosomiasis in the Kpong Head ...

African Journals Online (AJOL)

Schistosomiasis, a parasitic disease caused by the blood fluke Schistosoma sp. became a serious public health problem in Ghana after the Volta River was dammed in Akosombo in 1964. The formation of the Kpong head pond, about 25 km below the Akosombo dam, as a result of a second dam built at Kpong became an ...

In vitro uptake of /sup 14/C-praziquantel by cestodes, trematodes, and a nematode

Energy Technology Data Exchange (ETDEWEB)

Andrews, P.; Thomas, H.; Weber, H.

1980-12-01

/sup 14/C-praziquantel was rapidly taken up by Schistosoma mansoni, Fasciola hepatica, Hymenolepis nana, and isolated strobilocerci of Taenia taeniaeformis. Schistosoma mansoni lost praziquantel rapidly to drug-free medium. Chromatography of extracts prepared after incubation of S. mansoni and H. nana yielded no indication that praziquantel was metabolized. Autoradiography revealed a uniform distribution of praziquantel throughout the tissues of S. mansoni and H. nana. Uptake was considerably slower in the nematode Heterakis spumosa and apparently via the oral route.

Reproduction and caste ratios under stress in trematode colonies with a division of labour.

Science.gov (United States)

Lloyd, Melanie M; Poulin, Robert

2013-06-01

Trematodes form clonal colonies in their first intermediate host. Individuals are, depending on species, rediae or sporocysts (which asexually reproduce) and cercariae (which develop within rediae or sporocysts and infect the next host). Some species use a division of labour within colonies, with 2 distinct redial morphs: small rediae (non-reproducing) and large rediae (individuals which produce cercariae). The theory of optimal caste ratio predicts that the ratio of caste members (small to large rediae) responds to environmental variability. This was tested in Philophthalmus sp. colonies exposed to host starvation and competition with the trematode, Maritrema novaezealandensis. Philophthalmus sp. infected snails, with and without M. novaezealandensis, were subjected to food treatments. Reproductive output, number of rediae, and the ratio of small to large rediae were compared among treatments. Philophthalmus sp. colonies responded to host starvation and competition; reproductive output was higher in well-fed snails of both infection types compared with snails in lower food treatments and well-fed, single infected snails compared with well-fed double infected snails. Furthermore, the caste ratio in Philophthalmus sp. colonies was altered in response to competition. This is the first study showing caste ratio responses to environmental pressures in trematodes with a division of labour.

Coinfection with a novel fibropapilloma-associated herpesvirus and a novel Spirorchis sp. in an eastern box turtle (Terrapene carolina) in Florida.

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Yonkers, Sara B; Schneider, Renata; Reavill, Drury R; Archer, Linda L; Childress, April L; Wellehan, James F X

2015-07-01

Herpesviruses are important pathogens of chelonians, and include Chelonid herpesvirus 5, which is associated with fibropapillomatosis in sea turtles. Spirorchid trematodes are blood flukes that reside within the cardiovascular system of marine turtles and may be associated with severe disease. An eastern box turtle (Terrapene carolina) at the South Florida Wildlife Care Center (Fort Lauderdale, Florida) was presented to the facility with papillomatous growths behind both rear legs. Surgical removal resulted in remission for 8 months; however, lesions recurred, prompting a second surgery and acyclovir therapy. Surgical biopsies revealed subacute superficial inflammation associated with the supporting stroma of the cutaneous papillomas and granulomas within the superficial dermis containing fragmented and collapsed brown trematode eggs surrounded by multinucleated giant cells and epithelioid macrophages. Pan-herpesviral and pan-trematode consensus polymerase chain reaction and sequencing were run on tissue samples. Comparative sequence analysis revealed a novel alphaherpesvirus and a novel trematode in the genus Spirorchis. The animal became anorexic and was euthanized due to poor quality of life. While we do not yet have a complete understanding of the effects of herpesvirus and trematode infections in eastern box turtles, the findings thus presented provide initial insights into the disease relationships among these chelonians. © 2015 The Author(s).

[Genomics and transcriptomics of the Chinese liver fluke Clonorchis sinensis (Opisthorchiidae, Trematoda)].

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Chelomina, G N

2017-01-01

The review summarizes the results of first genomic and transcriptomic investigations of the liver fluke Clonorchis sinensis (Opisthorchiidae, Trematoda). The studies mark the dawn of the genomic era for opisthorchiids, which cause severe hepatobiliary diseases in humans and animals. Their results aided in understanding the molecular mechanisms of adaptation to parasitism, parasite survival in mammalian biliary tracts, and genome dynamics in the individual development and the development of parasite-host relationships. Special attention is paid to the achievements in studying the codon usage bias and the roles of mobile genetic elements (MGEs) and small interfering RNAs (siRNAs). Interspecific comparisons at the genomic and transcriptomic levels revealed molecular differences, which may contribute to understanding the specialized niches and physiological needs of the respective species. The studies in C. sinensis provide a basis for further basic and applied research in liver flukes and, in particular, the development of efficient means to prevent, diagnose, and treat clonorchiasis.

Some studies on liver and rumen flukes of bovines in Sri Lanka

African Journals Online (AJOL)

nkpc001

Keywords: liver and rumen flukes, bovines, influence of climate, Sri Lanka. INTRODUCTION .... they were given two changes of absolute alcohol, each longing ..... inland and where fresh water ditches, streams and large water ... India. Res. ull. Panjab Univ., New series, 18: 369-337. sen J, Perry B. 1994. The epidemiology,.

High Prevalence of Human Liver Infection by Amphimerus spp. Flukes, Ecuador

OpenAIRE

Calvopiña, Manuel; Cevallos, William; Kumazawa, Hideo; Eisenberg, Joseph

2011-01-01

Amphimerus spp. flukes are known to infect mammals, but human infections have not been confirmed. Microscopy of fecal samples from 397 persons from Ecuador revealed Opisthorchiidae eggs in 71 (24%) persons. Light microscopy of adult worms and scanning electron microscopy of eggs were compatible with descriptions of Amphimerus spp. This pathogen was only observed in communities that consumed undercooked fish.

Application of radioisotope tracer techniques in studies on host-parasite relationships, with special reference to larval trematodes. A review

International Nuclear Information System (INIS)

Christensen, N.Oe.

1981-01-01

The application of radioisotope tracer techniques in studies on various host-parasite relationships between larval trematodes and their intermediate and definite hosts is reviewed. Such studies comprise, for example, the reproduction and nutrition of various developmental stages of trematodes in relation to host and environment. The preparation and application of radiolabelled larvae are also discussed with special emphasis on their use in studies on free-living ecology and migration in hosts. (author)

Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis

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Hany Sady

2015-07-01

Full Text Available The present study describes a real-time PCR approach with high resolution melting-curve (HRM assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1 gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01. In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays.

Gynecological manifestations, histopathological findings, and schistosoma-specific polymerase chain reaction results among women with Schistosoma haematobium infection

DEFF Research Database (Denmark)

Randrianasolo, Bodo Sahondra; Jourdan, Peter Mark; Ravoniarimbinina, Pascaline

2015-01-01

BACKGROUND: The pathophysiology of female genital schistosomiasis (FGS) is only partially understood. This study aims to describe the histopathological findings, polymerase chain reaction (PCR) results, and gynecological manifestations of FGS in women with different intensities of Schistosoma hae...

Identification of Fasciola flukes in Thailand based on their spermatogenesis and nuclear ribosomal DNA, and their intraspecific relationships based on mitochondrial DNA.

Science.gov (United States)

Chaichanasak, Pannigan; Ichikawa, Madoka; Sobhon, Prasert; Itagaki, Tadashi

2012-12-01

We analyzed 147 Fasciola flukes obtained from cattle in Thailand based on their spermatogenetic ability, and nuclear ribosomal internal transcribed spacer 1 (ITS1) and mitochondrial nicotiamide adenine dinucleotide dehydrogenase subunit 1 (ND1) genes as molecular markers. One hundred twenty-eight flukes, which had abundant sperm in their seminal vesicles (spermic) and showed the PCR-RFLP pattern of F. gigantica in the ITS1, were accurately identified as F. gigantica. The other 19 flukes that had no sperm in their seminal vesicles were aspermic Fasciola sp. with the RFLP patterns identical to that of F. gigantica. Twenty-nine ND1 haplotypes (Fg-ND1-Thai 2-30) were distinguished in the 128 F. gigantica flukes and were divided into haplotypes unique to Thailand and those common to other countries, suggesting the possibility that ancestral haplotypes were introduced into Thailand. Three haplotypes (Fg-ND1-Thai 7, 9 and 27) appeared to be the major haplotypes found in F. gigantica from Thailand. Only one haplotype (Fg-ND1-Thai 1) was found in the 19 aspermic Fasciola sp. flukes obtained from geographical regions, and the nucleotide sequence of Fg-ND1-Thai 1 was identical to that of the aspermic Fasciola sp. from Japan, Korea, China, Vietnam and Myanmar, suggesting that they were descendants with a common provenance and expanded to these countries in the relatively recent past. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Evolution of sarcoma 180 (ascitic tumor in mice infected with Schistosoma mansoni

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Fausto Edmundo Lima Pereira

1986-03-01

Full Text Available Mice infected with 60 cercariae of Schistosoma mansoni were more resistant to the sarcoma 180 ascites tumor. Tumor inoculation was performed 50 days after schistosoma infection and the animals were observed and weighed at 48 hours intervals for development and progression of malignancy. In infected mice the weight gain (ascites formation started later and was shorter than in uninfected Controls. Also, the number of tumor cells into the peritoneal cavity 72h after tumor implantation was shorter in infected group than incontrols. This in creased resistance against a transplantable tumor probably is related to the effect of endotoxin on tumoricidal activity of macrophages activated by the infection. The immunodepression induced by Schistosoma mansoni infection enhances the proliferation of endogenous bacteria increasing the amount of endotoxin absorbed from the gut.

A comparison of the efficacy of doramectin, closantel and levamisole in the treatment of the 'oriental eye fluke', Philophthalmus gralli, in commercially reared ostriches (Struthio camelus : short communication

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S. Mukaratirwa

2008-05-01

Full Text Available Commercially reared ostriches at Msengi farm situated in the Chinhoyi area of Mashonaland West province in Zimbabwe were found to be infected with the 'oriental eye fluke', Philopthalmus gralli, in 2001. This was the 1st record of the fluke in Zimbabwe. Trials were conducted to identify a suitable drug for the treatment of this fluke. A total of 12 ostriches confirmed to be infected with the fluke through clinical examination of the eyes and identification of the fluke were randomly divided into 3 equal groups, with each group receiving a different treatment protocol. The 3 drugs used were doramectin, levamisole and closantel. Each of the drugs was used in combination with chloramphenicol as an eye ointment. Levamisole was administered topically into the eye whereas doramectin and closantel were administered parenterally as an intramuscular injection. The results indicated a positive response in levamisole-treated birds but there were no noticeable responses to doramectin and closantel treatments.

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana.

Science.gov (United States)

Baines, Lydia; Morgan, Eric R; Ofthile, Mphoeng; Evans, Kate

2015-04-01

It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%), and nematode (77%) and trematode (24%) eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685) than in all-male groups (529, sd 468). Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1-15 months. Possible reasons for associations between other factors and infection levels are discussed.

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana

Directory of Open Access Journals (Sweden)

Lydia Baines

2015-04-01

Full Text Available It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%, and nematode (77% and trematode (24% eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685 than in all-male groups (529, sd 468. Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1–15 months. Possible reasons for associations between other factors and infection levels are discussed.

The role of host nutrition in the pathogensis of liver fluke anaemia

International Nuclear Information System (INIS)

Berry, C.I.; Dargie, J.D.

1976-01-01

Although it is widely accepted that the course of many helminth diseases of sheep is determined by two main variables, namely the level of infection and the host's nutritional status, the importance of the latter in the pathogenesis of ovine fascioliasis remains to be determined. The results of the experiment described here demonstrate that dietary quality has no significant effect upon fluke establishment but profoundly influences the severity of the disease as evidenced by the more rapid development of anaemia and by earlier mortalities among sheep restricted to a maintenance ration (containing about 6% crude protein) compared with similarly infected animals receiving a diet commensurate with growth (13% crude protein). Concurrent measurements of blood volume and of red cell turnover using radioisotopic methods revealed that in all animals the anaemia was caused by a combination of haemodilution, intra-hepatic and biliary haemorrhage, but that the earlier and more severe disturbances in protein-restricted sheep reflected the earlier development of these changes in association with a faster rate of fluke migration, and was ultimately complicated by impaired erythropoiesis arising from iron deficiency. (author)

Helminths and Cancers From the Evolutionary Perspective.

Science.gov (United States)

Scholte, Larissa L S; Pascoal-Xavier, Marcelo A; Nahum, Laila A

2018-01-01

Helminths include free-living and parasitic Platyhelminthes and Nematoda which infect millions of people worldwide. Some Platyhelminthes species of blood flukes ( Schistosoma haematobium, Schistosoma japonicum , and Schistosoma mansoni ) and liver flukes ( Clonorchis sinensis and Opisthorchis viverrini ) are known to be involved in human cancers. Other helminths are likely to be carcinogenic. Our main goals are to summarize the current knowledge of human cancers caused by Platyhelminthes, point out some helminth and human biomarkers identified so far, and highlight the potential contributions of phylogenetics and molecular evolution to cancer research. Human cancers caused by helminth infection include cholangiocarcinoma, colorectal hepatocellular carcinoma, squamous cell carcinoma, and urinary bladder cancer. Chronic inflammation is proposed as a common pathway for cancer initiation and development. Furthermore, different bacteria present in gastric, colorectal, and urogenital microbiomes might be responsible for enlarging inflammatory and fibrotic responses in cancers. Studies have suggested that different biomarkers are involved in helminth infection and human cancer development; although, the detailed mechanisms remain under debate. Different helminth proteins have been studied by different approaches. However, their evolutionary relationships remain unsolved. Here, we illustrate the strengths of homology identification and function prediction of uncharacterized proteins from genome sequencing projects based on an evolutionary framework. Together, these approaches may help identifying new biomarkers for disease diagnostics and intervention measures. This work has potential applications in the field of phylomedicine (evolutionary medicine) and may contribute to parasite and cancer research.

Helminths and Cancers From the Evolutionary Perspective

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Larissa L. S. Scholte

2018-04-01

Full Text Available Helminths include free-living and parasitic Platyhelminthes and Nematoda which infect millions of people worldwide. Some Platyhelminthes species of blood flukes (Schistosoma haematobium, Schistosoma japonicum, and Schistosoma mansoni and liver flukes (Clonorchis sinensis and Opisthorchis viverrini are known to be involved in human cancers. Other helminths are likely to be carcinogenic. Our main goals are to summarize the current knowledge of human cancers caused by Platyhelminthes, point out some helminth and human biomarkers identified so far, and highlight the potential contributions of phylogenetics and molecular evolution to cancer research. Human cancers caused by helminth infection include cholangiocarcinoma, colorectal hepatocellular carcinoma, squamous cell carcinoma, and urinary bladder cancer. Chronic inflammation is proposed as a common pathway for cancer initiation and development. Furthermore, different bacteria present in gastric, colorectal, and urogenital microbiomes might be responsible for enlarging inflammatory and fibrotic responses in cancers. Studies have suggested that different biomarkers are involved in helminth infection and human cancer development; although, the detailed mechanisms remain under debate. Different helminth proteins have been studied by different approaches. However, their evolutionary relationships remain unsolved. Here, we illustrate the strengths of homology identification and function prediction of uncharacterized proteins from genome sequencing projects based on an evolutionary framework. Together, these approaches may help identifying new biomarkers for disease diagnostics and intervention measures. This work has potential applications in the field of phylomedicine (evolutionary medicine and may contribute to parasite and cancer research.

Molecular evidence shows that the liver fluke Fasciola gigantica is the predominant Fasciola species in ruminants from Pakistan.

Science.gov (United States)

Chaudhry, U; van Paridon, B; Shabbir, M Z; Shafee, M; Ashraf, K; Yaqub, T; Gilleard, J

2016-03-01

Fascioliasis is an important disease affecting livestock, with great costs to producers worldwide. It has also become a serious issue for human populations in some endemic areas as an emerging zoonotic infection. There are two Fasciola species of liver fluke responsible for this disease, which occur worldwide, Fasciola hepatica and Fasciola gigantica. Identifying these two species on the basis of adult or egg morphology requires specialist knowledge due to the similarity of characters, and may misidentify putative intermediate or hybrid forms. In this study we sequenced the internal transcribed spacer 2 (ITS-2) rDNA of liver flukes collected from multiple species of hosts from seven localities in the Punjab and Baluchistan provinces of Pakistan, to determine the distribution of these two species. All 46 flukes processed in this study, collected from seven sites, showed the rDNA ITS-2 genotype corresponding to F. gigantica, contradicting previous reports, based on adult and egg morphology, that both species are present in Pakistan, with F. hepatica being the more common.

Elucidation of the first definitively identified life cycle for a marine turtle blood fluke (Trematoda: Spirorchiidae) enables informed control.

Science.gov (United States)

Cribb, Thomas H; Crespo-Picazo, Jose L; Cutmore, Scott C; Stacy, Brian A; Chapman, Phoebe A; García-Párraga, Daniel

2017-01-01

Blood flukes of the family Spirorchiidae are significant pathogens of both free-ranging and captive marine turtles. Despite a significant proportion of marine turtle mortality being attributable to spirorchiid infections, details of their life cycles remain almost entirely unknown. Here we report on the molecular elucidation of the complete life cycle of a marine spirorchiid, identified as Amphiorchis sp., infecting vermetid gastropods and captive hatched neonate Caretta caretta in the Oceanogràfic Aquarium, in Valencia, Spain. Specimens of a vermetid gastropod, Thylaeodus cf. rugulosus (Monterosato, 1878), collected from the aquarium filtration system housing diseased C. caretta, were infected with sporocysts and cercariae consistent with the family Spirorchiidae. We generated rDNA sequence data [internal transcribed spacer 2 (ITS2) and partial 28S rDNA] from infections from the vermetid which were identical to sequences generated from eggs from the serosa of the intestine of neonate C. caretta, and an adult spirorchiid from the liver of a C. caretta from Florida, USA. Given the reliability of these markers in the delineation of trematode species, we consider all three stages to represent the same species and tentatively identify it as a species of Amphiorchis Price, 1934. The source of infection at the Oceanogràfic Foundation Rehabilitation Centre, Valencia, Spain, is inferred to be an adult C. caretta from the western Mediterranean being rehabilitated in the same facility. Phylogenetic analysis suggests that this Amphiorchis sp. is closely related to other spirorchiids of marine turtles (species of Carettacola Manter & Larson, 1950, Hapalotrema Looss, 1899 and Learedius Price, 1934). We discuss implications of the present findings for the control of spirorchiidiasis in captivity, for the better understanding of epidemiology in wild individuals, and the elucidation of further life cycles. Copyright © 2016 Australian Society for Parasitology. Published by

Nuclear magnetic resonance (NMR): application to examine liver tissues during invasion of the Liver fluke in cattle

International Nuclear Information System (INIS)

Wranicz, M.; Podbielski, T.; Grabiec, S.

1989-01-01

The T 1 and T 2 relaxation times of protons of hydrogen in the liver parenchyma and biliary ducts in normal and parazitized by the Liver fluke cows were determined. A method of the NMR in which a lenght or relaxation time is an index was applied. The value of this index is characteristic for determined physiological and pathological states of cells and it reveals changes which developed in body cells. It was found that tissues of cows parazitized by the Liver fluke (parenchyma and biliary ducts) and healthy ones differ significantly by the lenght of relaxation times. Parazitized tissues show a longer relaxation time than tissues of normal cows. (author)

Schistosoma real-time PCR as diagnostic tool for international travellers and migrants.

Science.gov (United States)

Cnops, Lieselotte; Tannich, Egbert; Polman, Katja; Clerinx, Jan; Van Esbroeck, Marjan

2012-10-01

To evaluate the use of a genus-specific PCR that combines high sensitivity with the detection of different Schistosoma species for diagnosis in international travellers and migrants in comparison to standard microscopy. The genus-specific real-time PCR was developed to target the 28S ribosomal RNA gene of the major human Schistosoma species. It was validated for analytical specificity and reproducibility and demonstrated an analytical sensitivity of 0.2 eggs per gram of faeces. Its diagnostic performance was further evaluated on 152 faecal, 32 urine and 38 serum samples from patients presenting at the outpatient clinic of the Institute of Tropical Medicine in Antwerp (Belgium). We detected Schistosoma DNA in 76 faecal (50.0%) and five urine (15.6%) samples of which, respectively, nine and one were not detected by standard microscopy. Only two of the 38 serum samples of patients with confirmed schistosomiasis were positive with the presently developed PCR. Sequence analysis on positive faecal samples allowed identification of the Schistosoma species complex. The real-time PCR is highly sensitive and may offer added value in diagnosing imported schistosomiasis. The genus-specific PCR can detect all schistosome species that are infectious to humans and performs very well with faeces and urine, but not in serum. © 2012 Blackwell Publishing Ltd.

Rapid Detection and Differentiation of Clonorchis sinensis and Opisthorchis viverrini Using Real-Time PCR and High Resolution Melting Analysis

OpenAIRE

Cai, Xian-Quan; Yu, Hai-Qiong; Li, Rong; Yue, Qiao-Yun; Liu, Guo-Hua; Bai, Jian-Shan; Deng, Yan; Qiu, De-Yi; Zhu, Xing-Quan

2014-01-01

Clonorchis sinensis and Opisthorchis viverrini are both important fish-borne pathogens, causing serious public health problem in Asia. The present study developed an assay integrating real-time PCR and high resolution melting (HRM) analysis for the specific detection and rapid identification of C. sinensis and O. viverrini. Primers targeting COX1 gene were highly specific for these liver flukes, as evidenced by the negative amplification of closely related trematodes. Assays using genomic DNA...

Molecular identification of Clonorchis sinensis and discrimination with other opisthorchid liver fluke species using multiple Ligation-depended Probe Amplification (MLPA

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Liang Chi

2011-06-01

Full Text Available Abstract Background Infections with the opisthorchid liver flukes Clonorchis sinensis, Opisthorchis viverrini, and O. felineus cause severe health problems globally, particularly in Southeast Asia. Early identification of the infection is essential to provide timely and appropriate chemotherapy to patients. Results In this study we evaluate a PCR-based molecular identification method, Multiplex Ligation-dependent Probe Amplification (MLPA, which allows rapid and specific detection of single nucleotide acid differences between Clonorchis sinensis, Opisthorchis viverrini and O. felineus. Three probe pairs were derived from the Internally Transcribed Spacer 1 (ITS1 of three opisthorchid liver flukes using a systematic phylogenetic analysis. Specific loci were detected in all three species, yielding three amplicons with 198,172 and 152 bp, respectively, while no cross reactions were observed. A panel of 66 C. sinensis isolates was screened using MLPA. All species were positively identified, and no inhibition was observed. The detection limit was 103 copies of the ITS gene for the three liver flukes, or about 60 pg genomic DNA for Clonorchis sinensis. Amplification products can be detected by electrophoresis on agarose gel or in a capillary sequencer. In addition, genomic DNA of Clonorchis sinensis in fecal samples of infected rats was positively amplified by MLPA. Conclusion The flexibility and specificity make MLPA a potential tool for specific identification of infections by opisthorchid liver flukes in endemic areas.

case report endomyocardial fibrosis associated with schistosoma

African Journals Online (AJOL)

2014-12-01

Dec 1, 2014 ... stored in containers and subsequently used for bathing. Both patients were ... His urine was amber and of adequate vol- ume. He had been ... schistosome specific antibody test for Schistosoma haematobium ... health problem, with the highest prevalence seen in communities ... newer drug targets.13,14.

Gambaran Nilai Darah Pada Sapi Yang Terinfeksi Fascioliasis Yang Dipotong di Rumah Potong Hewan Kota Banda Aceh

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Winaruddin Winaruddin

2002-04-01

Full Text Available ABSTRACT.The main purpose of the research was to determain the blood value of fascioliasis on blood of the cattle slaughtered in abattoir. It has been examined fifty samples of fecal, bile fluids and blood of the cattle slaughtered at the Banda Aceh abattoir. The samples were examined for the values of hematocrit, erythrocyte and leucocyte differentiation and the presence of helminth eggs respectively. It was found that the egg count variet from 7.168 ± 0.225 trematode eggs in fecal samples and 14.554 ± 2.154 trematode eggs in bile duct repectively. The result of this study showed that, the prevalence rate of fascioliasis in cattle categorical a mild infestation was 44 %. Both in the length and width of body size of the flukes are affected by the life stage. The size of adult fluke was about 34.649 ± 8.992 mm x 12.030 ± 3.494 mm, while that of young fluke was 1.650 ± 0.240 mm x 1.487 ± 0.227 mm. the blood indices of affected cattle indicated significant (P < 0.05 decrease in hematocrit and erythrocyte count compared with those not affected by the disease. The mean count of hematocrit and erythrocyte 29.773%  ± 3.366% and 547.337 x 104  ± 13.599 in cattle infected and in cattle non infected was 32.357 ± 2.818 and 566.457 x 104  ± 12.886 respectively. The result of this study, also significant (P < 0.05 in increasing of the eosinophilia 16.22%  ± 4.03% compared with that non-affected ones (10.54 ± 4.56.

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa)

OpenAIRE

Benamrouz S.; Conseil V.; Creusy C.; Calderon E.; Dei-Cas E.; Certad G.

2012-01-01

The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozo...

Mutagenicity of nicotine in Schistosoma mansoni - infected mice ...

African Journals Online (AJOL)

Analysis of meiotic chromosomes showed significant elevation in the Schistosoma-infected mice. Administration of nicotine to infected mice substantially increased the percentages of micronucleated cells and total CAs. The percentage of chromosomal abnormalities in spermatocyte metaphase-I cells increased significantly ...

Development and validation of a quantitative, high-throughput, fluorescent-based bioassay to detect schistosoma viability.

Directory of Open Access Journals (Sweden)

Emily Peak

2010-07-01

Full Text Available Schistosomiasis, caused by infection with the blood fluke Schistosoma, is responsible for greater than 200,000 human deaths per annum. Objective high-throughput screens for detecting novel anti-schistosomal targets will drive 'genome to drug' lead translational science at an unprecedented rate. Current methods for detecting schistosome viability rely on qualitative microscopic criteria, which require an understanding of parasite morphology, and most importantly, must be subjectively interpreted. These limitations, in the current state of the art, have significantly impeded progress into whole schistosome screening for next generation chemotherapies.We present here a microtiter plate-based method for reproducibly detecting schistosomula viability that takes advantage of the differential uptake of fluorophores (propidium iodide and fluorescein diacetate by living organisms. We validate this high-throughput system in detecting schistosomula viability using auranofin (a known inhibitor of thioredoxin glutathione reductase, praziquantel and a range of small compounds with previously-described (gambogic acid, sodium salinomycin, ethinyl estradiol, fluoxetidine hydrochloride, miconazole nitrate, chlorpromazine hydrochloride, amphotericin b, niclosamide or suggested (bepridil, ciclopirox, rescinnamine, flucytosine, vinblastine and carbidopa anti-schistosomal activities. This developed method is sensitive (200 schistosomula/well can be assayed, relevant to industrial (384-well microtiter plate compatibility and academic (96-well microtiter plate compatibility settings, translatable to functional genomics screens and drug assays, does not require a priori knowledge of schistosome biology and is quantitative.The wide-scale application of this fluorescence-based bioassay will greatly accelerate the objective identification of novel therapeutic lead targets/compounds to combat schistosomiasis. Adapting this bioassay for use with other parasitic worm species

Solution Structure, Membrane Interactions, and Protein Binding Partners of the Tetraspanin Sm-TSP-2, a Vaccine Antigen from the Human Blood Fluke Schistosoma mansoni*

Science.gov (United States)

Jia, Xinying; Schulte, Leigh; Loukas, Alex; Pickering, Darren; Pearson, Mark; Mobli, Mehdi; Jones, Alun; Rosengren, Karl J.; Daly, Norelle L.; Gobert, Geoffrey N.; Jones, Malcolm K.; Craik, David J.; Mulvenna, Jason

2014-01-01

The tetraspanins (TSPs) are a family of integral membrane proteins that are ubiquitously expressed at the surface of eukaryotic cells. TSPs mediate a range of processes at the surface of the plasma membrane by providing a scaffold for the assembly of protein complexes known as tetraspanin-enriched microdomains (TEMs). We report here the structure of the surface-exposed EC2 domain from Sm-TSP-2, a TSP from Schistosoma mansoni and one of the better prospects for the development of a vaccine against schistosomiasis. This is the first solution structure of this domain, and our investigations of its interactions with lipid micelles provide a general model for interactions between TSPs, membranes, and other proteins. Using chemical cross-linking, eight potential protein constituents of Sm-TSP-2-mediated TEMs were also identified. These include proteins important for membrane maintenance and repair, providing further evidence for the functional role of Sm-TSP-2- and Sm-TSP-2-mediated TEMs. The identification of calpain, Sm29, and fructose-bisphosphate aldolase, themselves potential vaccine antigens, suggests that the Sm-TSP-2-mediated TEMs could be disrupted via multiple targets. The identification of further Sm-TSP-2-mediated TEM proteins increases the available candidates for multiplex vaccines and/or novel drugs targeting TEMs in the schistosome tegument. PMID:24429291

Solution structure, membrane interactions, and protein binding partners of the tetraspanin Sm-TSP-2, a vaccine antigen from the human blood fluke Schistosoma mansoni.

Science.gov (United States)

Jia, Xinying; Schulte, Leigh; Loukas, Alex; Pickering, Darren; Pearson, Mark; Mobli, Mehdi; Jones, Alun; Rosengren, Karl J; Daly, Norelle L; Gobert, Geoffrey N; Jones, Malcolm K; Craik, David J; Mulvenna, Jason

2014-03-07

The tetraspanins (TSPs) are a family of integral membrane proteins that are ubiquitously expressed at the surface of eukaryotic cells. TSPs mediate a range of processes at the surface of the plasma membrane by providing a scaffold for the assembly of protein complexes known as tetraspanin-enriched microdomains (TEMs). We report here the structure of the surface-exposed EC2 domain from Sm-TSP-2, a TSP from Schistosoma mansoni and one of the better prospects for the development of a vaccine against schistosomiasis. This is the first solution structure of this domain, and our investigations of its interactions with lipid micelles provide a general model for interactions between TSPs, membranes, and other proteins. Using chemical cross-linking, eight potential protein constituents of Sm-TSP-2-mediated TEMs were also identified. These include proteins important for membrane maintenance and repair, providing further evidence for the functional role of Sm-TSP-2- and Sm-TSP-2-mediated TEMs. The identification of calpain, Sm29, and fructose-bisphosphate aldolase, themselves potential vaccine antigens, suggests that the Sm-TSP-2-mediated TEMs could be disrupted via multiple targets. The identification of further Sm-TSP-2-mediated TEM proteins increases the available candidates for multiplex vaccines and/or novel drugs targeting TEMs in the schistosome tegument.

Assessing the Role of Climate Variability on Liver Fluke Risk in the UK Through Mechanistic Hydro-Epidemiological Modelling

Science.gov (United States)

Beltrame, L.; Dunne, T.; Rose, H.; Walker, J.; Morgan, E.; Vickerman, P.; Wagener, T.

2016-12-01

Liver fluke is a flatworm parasite infecting grazing animals worldwide. In the UK, it causes considerable production losses to cattle and sheep industries and costs farmers millions of pounds each year due to reduced growth rates and lower milk yields. Large part of the parasite life-cycle takes place outside of the host, with its survival and development strongly controlled by climatic and hydrologic conditions. Evidence of climate-driven changes in the distribution and seasonality of fluke disease already exists, as the infection is increasingly expanding to new areas and becoming a year-round problem. Therefore, it is crucial to assess current and potential future impacts of climate variability on the disease to guide interventions at the farm scale and mitigate risk. Climate-based fluke risk models have been available since the 1950s, however, they are based on empirical relationships derived between historical climate and incidence data, and thus are unlikely to be robust for simulating risk under changing conditions. Moreover, they are not dynamic, but estimate risk over large regions in the UK based on monthly average climate conditions, so they do not allow investigating the effects of climate variability for supporting farmers' decisions. In this study, we introduce a mechanistic model for fluke, which represents habitat suitability for disease development at 25m resolution with a daily time step, explicitly linking the parasite life-cycle to key hydro-climate conditions. The model is used on a case study in the UK and sensitivity analysis is performed to better understand the role of climate variability on the space-time dynamics of the disease, while explicitly accounting for uncertainties. Comparisons are presented with experts' knowledge and a widely used empirical model.

Red fluorescent protein responsible for pigmentation in trematode-infected Porites compressa tissues.

Science.gov (United States)

Palmer, Caroline V; Roth, Melissa S; Gates, Ruth D

2009-02-01

Reports of coral disease have increased dramatically over the last decade; however, the biological mechanisms that corals utilize to limit infection and resist disease remain poorly understood. Compromised coral tissues often display non-normal pigmentation that potentially represents an inflammation-like response, although these pigments remain uncharacterized. Using spectral emission analysis and cryo-histological and electrophoretic techniques, we investigated the pink pigmentation associated with trematodiasis, infection with Podocotyloides stenometre larval trematode, in Porites compressa. Spectral emission analysis reveals that macroscopic areas of pink pigmentation fluoresce under blue light excitation (450 nm) and produce a broad emission peak at 590 nm (+/-6) with a 60-nm full width at half maximum. Electrophoretic protein separation of pigmented tissue extract confirms the red fluorescence to be a protein rather than a low-molecular-weight compound. Histological sections demonstrate green fluorescence in healthy coral tissue and red fluorescence in the trematodiasis-compromised tissue. The red fluorescent protein (FP) is limited to the epidermis, is not associated with cells or granules, and appears unstructured. These data collectively suggest that the red FP is produced and localized in tissue infected by larval trematodes and plays a role in the immune response in corals.

The roles of water, sanitation and hygiene in reducing schistosomiasis: a review

OpenAIRE

Grimes, Jack ET; Croll, David; Harrison, Wendy E; Utzinger, J?rg; Freeman, Matthew C; Templeton, Michael R

2015-01-01

Schistosomiasis is a disease caused by infection with blood flukes of the genus Schistosoma. Transmission of, and exposure to, the parasite result from faecal or urinary contamination of freshwater containing intermediate host snails, and dermal contact with the same water. The World Health Assembly resolution 65.21 from May 2012 urges member states to eliminate schistosomiasis through preventive chemotherapy (i.e. periodic large-scale administration of the antischistosomal drug praziquantel ...

Evidence for high genetic diversity of NAD1 and COX1 mitochondrial haplotypes among triclabendazole resistant and susceptible populations and field isolates of Fasciola hepatica (liver fluke) in Australia.

Science.gov (United States)

Elliott, T; Muller, A; Brockwell, Y; Murphy, N; Grillo, V; Toet, H M; Anderson, G; Sangster, N; Spithill, T W

2014-02-24

In recent years, the global incidence of Fasciola hepatica (liver fluke) infections exhibiting resistance to triclabendazole (TCBZ) has increased, resulting in increased economic losses for livestock producers and threatening future control. The development of TCBZ resistance and the worldwide discovery of F. hepatica population diversity has emphasized the need to further understand the genetic structure of drug susceptible and resistant Fasciola populations within Australia. In this study, the genetic diversity of liver flukes was estimated by sequencing mitochondrial DNA (mtDNA) encoding the NAD1 (530 bp) and COX1 (420 bp) genes of 208 liver flukes (F. hepatica) collected from three populations: field isolates obtained from abattoirs from New South Wales (NSW) and Victoria (Vic); three TCBZ-resistant fluke populations from NSW and Victoria; and the well-established TCBZ-susceptible Sunny Corner laboratory isolate. Overall nucleotide diversity for all flukes analysed of 0.00516 and 0.00336 was estimated for the NAD1 and COX1 genes respectively. Eighteen distinct haplotypes were established for the NAD1 gene and six haplotypes for the COX1 gene, resulting in haplotype diversity levels of 0.832 and 0.482, respectively. One field isolate showed a similar low level of haplotype diversity as seen in the Sunny Corner laboratory isolate. Analysis of TCBZ-resistant infrapopulations from 3 individual cattle grazing one property revealed considerable sequence parasite diversity between cattle. Analysis of parasite TCBZ-resistant infrapopulations from sheep and cattle revealed haplotypes unique to each host, but no significant difference between parasite populations. Fst analysis of fluke populations revealed little differentiation between the resistant and field populations. This study has revealed a high level of diversity in field and drug resistant flukes in South-Eastern Australia. Copyright © 2013 Elsevier B.V. All rights reserved.

Chemometric and biological validation of a capillary electrophoresis metabolomic experiment of Schistosoma mansoni infection in mice.

Science.gov (United States)

Garcia-Perez, Isabel; Angulo, Santiago; Utzinger, Jürg; Holmes, Elaine; Legido-Quigley, Cristina; Barbas, Coral

2010-07-01

Metabonomic and metabolomic studies are increasingly utilized for biomarker identification in different fields, including biology of infection. The confluence of improved analytical platforms and the availability of powerful multivariate analysis software have rendered the multiparameter profiles generated by these omics platforms a user-friendly alternative to the established analysis methods where the quality and practice of a procedure is well defined. However, unlike traditional assays, validation methods for these new multivariate profiling tools have yet to be established. We propose a validation for models obtained by CE fingerprinting of urine from mice infected with the blood fluke Schistosoma mansoni. We have analysed urine samples from two sets of mice infected in an inter-laboratory experiment where different infection methods and animal husbandry procedures were employed in order to establish the core biological response to a S. mansoni infection. CE data were analysed using principal component analysis. Validation of the scores consisted of permutation scrambling (100 repetitions) and a manual validation method, using a third of the samples (not included in the model) as a test or prediction set. The validation yielded 100% specificity and 100% sensitivity, demonstrating the robustness of these models with respect to deciphering metabolic perturbations in the mouse due to a S. mansoni infection. A total of 20 metabolites across the two experiments were identified that significantly discriminated between S. mansoni-infected and noninfected control samples. Only one of these metabolites, allantoin, was identified as manifesting different behaviour in the two experiments. This study shows the reproducibility of CE-based metabolic profiling methods for disease characterization and screening and highlights the importance of much needed validation strategies in the emerging field of metabolomics.

Protection against Schistosoma mansoni infection using a Fasciola hepatica-derived fatty acid binding protein from different delivery systems.

Science.gov (United States)

Vicente, Belén; López-Abán, Julio; Rojas-Caraballo, Jose; del Olmo, Esther; Fernández-Soto, Pedro; Muro, Antonio

2016-04-18

Schistosomiasis is a water-borne disease afflicting over 261 million people in many areas of the developing countries with high morbidity and mortality. The control relies mainly on treatment with praziquantel. Fatty acid binding proteins (FABP) have demonstrated high levels of immune-protection against trematode infections. This study reports the immunoprotection induced by cross-reacting Fasciola hepatica FABP, native (nFh12) and recombinantly expressed using two different expression systems Escherichia coli (rFh15) and baculovirus (rFh15b) against Schistosoma mansoni infection. BALB/c mice were vaccinated with native nFh12 or recombinant rFh15 and rFh15 FABP from F. hepatica formulated in adjuvant adaptation (ADAD) system with natural or chemical synthesised immunomodulators (PAL and AA0029) and then challenged with 150 cercariae of S. mansoni. Parasite burden, hepatic lesions and antibody response were studied in vaccination trials. Furthermore differences between rFh15 and rFh15b immunological responses (cytokine production, splenocyte population and antibody levels) were studied. Vaccination with nFh12 induced significant reductions in worm burden (83%), eggs in tissues (82-92%) and hepatic lesions (85%) compared to infected controls using PAL. Vaccination with rFh15 showed lower total worm burden (56-64%), eggs in the liver (21-61%), eggs in the gut (30-77%) and hepatic damage (67-69%) using PAL and AA0029 as immunomodulators. In contrast, mice vaccinated with rFh15b showed only reductions in eggs trapped in the liver and intestine (53 and 60%, respectively), and hepatic lesions (45%). We observed a significant rise in TNFα, IL-6, IL-2, IL-4 and high antibody response (IgG, IgG1, IgG2a, IgM and IgE) in mice immunised with either rFh15 or rFh15b. Moreover, mice immunised with rFh15b showed an increase in IFNγ and a decrease in B220 cells compared to untreated mice, and less production of IgG1 and IgM than in mice immunised by rFh15. Higher level of

GIS-based spatial statistical analysis of risk areas for liver flukes in Surin Province of Thailand.

Science.gov (United States)

Rujirakul, Ratana; Ueng-arporn, Naporn; Kaewpitoon, Soraya; Loyd, Ryan J; Kaewthani, Sarochinee; Kaewpitoon, Natthawut

2015-01-01

It is urgently necessary to be aware of the distribution and risk areas of liver fluke, Opisthorchis viverrini, for proper allocation of prevention and control measures. This study aimed to investigate the human behavior, and environmental factors influencing the distribution in Surin Province of Thailand, and to build a model using stepwise multiple regression analysis with a geographic information system (GIS) on environment and climate data. The relationship between the human behavior, attitudes (R Square=0.878, and, Adjust R Square=0.849. By GIS analysis, we found Si Narong, Sangkha, Phanom Dong Rak, Mueang Surin, Non Narai, Samrong Thap, Chumphon Buri, and Rattanaburi to have the highest distributions in Surin province. In conclusion, the combination of GIS and statistical analysis can help simulate the spatial distribution and risk areas of liver fluke, and thus may be an important tool for future planning of prevention and control measures.

Zoonotic Trematode Metacercariae in Fish from Phnom Penh and Pursat, Cambodia

Science.gov (United States)

Chai, Jong-Yil; Na, Byoung-Kuk; Yong, Tai-Soon; Eom, Keeseon S.; Yoon, Cheong-Ha; Hoang, Eui-Hyug; Jeoung, Hoo-Gn; Socheat, Duong

2014-01-01

A survey was performed to investigate the infection status of freshwater fish with zoonotic trematode metacercariae in Phnom Penh and Pursat Province, Cambodia. All collected fish with ice were transferred to our laboratory and examined using the artificial digestion method. In fish from Phnom Penh, 2 kinds of metacercariae (Opisthorchis viverrini and Haplorchis yokogawai) were detected. O. viverrini metacercariae were positive in 37 (50.0%) of 74 fish in 11 species (average no. metacercariae/fish, 18.6). H. yokogawai metacercariae were detected in 23 (57.5%) of 40 fish in 5 species (average no. metacercariae/fish, 21.0). In fish from Pursat Province, 5 kinds of metacercariae (O. viverrini, H. yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum sp.) were detected; O. viverrini metacercariae (n=3) in 2 fish species (Henicorhynchus lineatus and Puntioplites falcifer), H. yokogawai metacercariae (n=51) in 1 species (P. falcifer), H. pumilio metacercariae (n=476) in 2 species (H. lineatus and Pristolepis fasciata), C. formosanus metacercariae (n=1) in 1 species (H. lineatus), and Procerovum sp. metacercariae (n=63) in 1 species (Anabas testudineus). From the above results, it has been confirmed that various freshwater fish play the role of a second intermediate host for zoonotic trematodes (O. viverrini, H. yokogawai, H. pumilio, C. formosanus, and Procerovum sp.) in Cambodia. PMID:24623879

Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake

Czech Academy of Sciences Publication Activity Database

Soldánová, Miroslava; Georgieva, Simona; Roháčová, Jana; Knudsen, R.; Kuhn, J. A.; Henriksen, E. H.; Siwertsson, A.; Shaw, J. C.; Kuris, A. M.; Amundsen, P.-A.; Scholz, Tomáš; Lafferty, K. D.; Kostadinova, Aneta

2017-01-01

Roč. 47, č. 6 (2017), s. 327-345 ISSN 0020-7519 R&D Projects: GA ČR GA15-14198S; GA ČR GAP505/10/1562 Institutional support: RVO:60077344 Keywords : Trematode diversity * intermediate hosts * phylogeny * mitochondrial DNA * nuclear DNA * Lake Takvatn * Norway * Sub-Arctic Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 3.730, year: 2016

Evaluation of Schistosoma mansoni morbidity one year after ...

African Journals Online (AJOL)

The design was a Prospective cohorts study; and the setting was a busy canoe landing sites along Albert Nile in Schistosoma (S) mansoni hyperendemic areas of Rhino Camp and Obongi fishing village were selected for the study. Previously in 2005, 1562 people including fishermen and women, school pupils, teachers, ...

The effects of farm management practices on liver fluke prevalence and the current internal parasite control measures employed on Irish dairy farms.

Science.gov (United States)

Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo

2015-01-30

Fasciolosis caused by Fasciola hepatica is responsible for major production losses in cattle farms. The objectives of this study were to assess the effect of farm management practices on liver fluke prevalence on Irish dairy farms and to document the current control measures against parasitic diseases. In total, 369 dairy farms throughout Ireland were sampled from October to December 2013, each providing a single bulk tank milk (BTM) sample for liver fluke antibody-detection ELISA testing and completing a questionnaire on their farm management. The analysis of samples showed that cows on 78% (n=288) of dairy farms had been exposed to liver fluke. There was a difference (P0.05) between positive and negative farms in (a) the grazing of dry cows together with replacement cows, (b) whether or not grazed grassland was mowed for conservation, (c) the type of drinking water provision system, (d) spreading of cattle manure on grassland or (e) for grazing season length (GSL; mean=262.5 days). Also, there were differences (Pmanagement practices between Irish farms with dairy herds exposed or not exposed to liver fluke and stressed the need of fine-scale mapping of the disease patterns even at farm level to increase the accuracy of risk models. Also, comprehensive advice and professional support services to farmers on appropriate farm management practices are very important for an effective anthelmintic control strategy. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of control strategies on the persistence of fish-borne zoonotic trematodes: A modelling approach

NARCIS (Netherlands)

Boerlage, A.S.; Graat, E.A.M.; Verreth, J.A.J.; Jong, de M.C.M.

2013-01-01

Fish-borne Zoonotic Trematodes (FZTs) are a risk to human health and need to be controlled. A mathematical model was developed to give insight into how and to what extent control strategies change the dynamics of FZTs on integrated agriculture–aquaculture farms. The reproduction ratio R evaluates

In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the fucosyltransferase multigene family.

Science.gov (United States)

Peterson, Nathan A; Anderson, Tavis K; Yoshino, Timothy P

2013-01-01

Fucosylated glycans of the parasitic flatworm Schistosoma mansoni play key roles in its development and immunobiology. In the present study we used a genome-wide homology-based bioinformatics approach to search for genes that contribute to fucosylated glycan expression in S. mansoni, specifically the α2-, α3-, and α6-fucosyltransferases (FucTs), which transfer L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. We identified and in silico characterized several novel schistosome FucT homologs, including six α3-FucTs and six α6-FucTs, as well as two protein O-FucTs that catalyze the unrelated transfer of L-fucose to serine and threonine residues of epidermal growth factor- and thrombospondin-type repeats. No α2-FucTs were observed. Primary sequence analyses identified key conserved FucT motifs as well as characteristic transmembrane domains, consistent with their putative roles as fucosyltransferases. Most genes exhibit alternative splicing, with multiple transcript variants generated. A phylogenetic analysis demonstrated that schistosome α3- and α6-FucTs form monophyletic clades within their respective gene families, suggesting multiple gene duplications following the separation of the schistosome lineage from the main evolutionary tree. Quantitative decreases in steady-state transcript levels of some FucTs during early larval development suggest a possible mechanism for differential expression of fucosylated glycans in schistosomes. This study systematically identifies the complete repertoire of FucT homologs in S. mansoni and provides fundamental information regarding their genomic organization, genetic variation, developmental expression, and evolutionary history.

Cross-sectional associations between intensity of animal and human infection with Schistosoma japonicum in Western Samar province, Philippines

DEFF Research Database (Denmark)

McGarvey, Stephen T.; Carabin, Hélène; Batalong, Ernesto Jr.

2006-01-01

To estimate the association between the intensity of animal infection with Schistosoma japonicum and human infection in Western Samar province, the Philippines......To estimate the association between the intensity of animal infection with Schistosoma japonicum and human infection in Western Samar province, the Philippines...

Morphological and Molecular Discrimination of Fasciola Species Isolated From Domestic Ruminants of Urmia City, Iran

Science.gov (United States)

YAKHCHALI, Mohammad; MALEKZADEH-VIAYEH, Reza; IMANI-BARAN, Abbas; MARDANI, Karim

2015-01-01

Background: The trematodes of the genus Fasciola (the liver flukes) are among the well-known instances of food-borne parasites worldwide. Differentiation of Fasciola species is important because of their different transmission and epidemiological characteristics. The current study was undertaken to discriminate Fasciola species in the domestic ruminants of Urmia city, Iran. Methods: Adult flukes were isolated from the naturally infected livers of the slaughtered water buffaloes and sheep. The flukes were initially identified based on morphological and morphometric parameters. A 618-bp-long fragment of the 28SrRNA gene of Fasciola was amplified by polymerase chain reaction (PCR). The amplified fragment was digested by DraII or AvaII enzymes for a restriction fragment length polymorphism (RFLP) analysis and sequenced for the phylogenetic tree construction. Results: Based on the morphometric examination, the flukes belonged to F. hepatica, F. gigantica and an intermediate Fasciola form. The PCR-RFLP analysis was able to differentiate F. hepatica from F. gigantica. While the phylogenetic reconstruction justified, to some extent, the morphological diagnosis, it failed to segregate F. hepatica from F. gigantica identified in this and the previous studies. Conclusion: To resolve fully the problem of taxonomy and evolution in Fasciola species, employing a broad range of molecular and morphological approaches is necessary. This is crucial for epidemiological surveys and successful clinical management of their infection. PMID:25904945

Morphological and molecular discrimination of fasciola species isolated from domestic ruminants of urmia city, iran.

Directory of Open Access Journals (Sweden)

Mohammad Yakhchali

2015-03-01

Full Text Available The trematodes of the genus Fasciola (the liver flukes are among the well-known instances of food-borne parasites worldwide. Differentiation of Fasciola species is important because of their different transmission and epidemiological characteristics. The current study was undertaken to discriminate Fasciola species in the domestic ruminants of Urmia city, Iran.Adult flukes were isolated from the naturally infected livers of the slaughtered water buffaloes and sheep. The flukes were initially identified based on morphological and morphometric parameters. A 618-bp-long fragment of the 28SrRNA gene of Fasciola was amplified by polymerase chain reaction (PCR. The amplified fragment was digested by DraII or AvaII enzymes for a restriction fragment length polymorphism (RFLP analysis and sequenced for the phylogenetic tree construction.Based on the morphometric examination, the flukes belonged to F. hepatica, F. gigantica and an intermediate Fasciola form. The PCR-RFLP analysis was able to differentiate F. hepatica from F. gigantica. While the phylogenetic reconstruction justified, to some extent, the morphological diagnosis, it failed to segregate F. hepatica from F. gigantica identified in this and the previous studies.To resolve fully the problem of taxonomy and evolution in Fasciola species, employing a broad range of molecular and morphological approaches is necessary. This is crucial for epidemiological surveys and successful clinical management of their infection.

Toward integrated opisthorchiasis control in northeast Thailand: the Lawa project.

Science.gov (United States)

Sripa, Banchob; Tangkawattana, Sirikachorn; Laha, Thewarach; Kaewkes, Sasithorn; Mallory, Frank F; Smith, John F; Wilcox, Bruce A

2015-01-01

Human liver fluke, Opisthorchis viverrini, a food-borne trematode is a significant public health problem in Southeast Asia, particularly in Thailand. Despite a long history of control programmes in Thailand and a nationwide reduction, O. viverrini infection prevalence remains high in the northeastern provinces. Therefore, a new strategy for controlling the liver fluke infection using the EcoHealth/One Health approach was introduced into the Lawa Lake area in Khon Kaen province where the liver fluke is endemic. A programme has been carried using anthelminthic treatment, novel intensive health education methods both in the communities and in schools, ecosystem monitoring and active community participation. As a result, the infection rate in the more than 10 villages surrounding the lake has declined to approximate one third of the average of 50% as estimated by a baseline survey. Strikingly, the Cyprinoid fish species in the lake, which are the intermediate host, now showed less than 1% prevalence compared to a maximum of 70% at baseline. This liver fluke control programme, named "Lawa model," is now recognised nationally and internationally, and being expanding to other parts of Thailand and neighbouring Mekong countries. Challenges to O. viverrini disease control, and lessons learned in developing an integrative control programme using a community-based, ecosystem approach, and scaling-up regionally based on Lawa as a model are described. Copyright © 2014 Elsevier B.V. All rights reserved.

Genetic Variation between Biomphalaria alexandrina Snails Susceptible and Resistant to Schistosoma mansoni Infection

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Suzanne M. F. El-Nassery

2013-01-01

Full Text Available Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

Rapid detection and differentiation of Clonorchis sinensis and Opisthorchis viverrini using real-time PCR and high resolution melting analysis.

Science.gov (United States)

Cai, Xian-Quan; Yu, Hai-Qiong; Li, Rong; Yue, Qiao-Yun; Liu, Guo-Hua; Bai, Jian-Shan; Deng, Yan; Qiu, De-Yi; Zhu, Xing-Quan

2014-01-01

Clonorchis sinensis and Opisthorchis viverrini are both important fish-borne pathogens, causing serious public health problem in Asia. The present study developed an assay integrating real-time PCR and high resolution melting (HRM) analysis for the specific detection and rapid identification of C. sinensis and O. viverrini. Primers targeting COX1 gene were highly specific for these liver flukes, as evidenced by the negative amplification of closely related trematodes. Assays using genomic DNA extracted from the two flukes yielded specific amplification and their identity was confirmed by sequencing, having the accuracy of 100% in reference to conventional methods. The assay was proved to be highly sensitive with a detection limit below 1 pg of purified genomic DNA, 5 EPG, or 1 metacercaria of C. sinensis. Moreover, C. sinensis and O. viverrini were able to be differentiated by their HRM profiles. The method can reduce labor of microscopic examination and the contamination of agarose electrophoresis. Moreover, it can differentiate these two flukes which are difficult to be distinguished using other methods. The established method provides an alternative tool for rapid, simple, and duplex detection of C. sinensis and O. viverrini.

Clonorchis sinensis and Clonorchiasis: The Relevance of Exploring Genetic Variation.

Science.gov (United States)

Wang, Daxi; Young, Neil D; Korhonen, Pasi K; Gasser, Robin B

2018-01-01

Parasitic trematodes (flukes) cause substantial mortality and morbidity in humans. The Chinese liver fluke, Clonorchis sinensis, is one of the most destructive parasitic worms in humans in China, Vietnam, Korea and the Russian Far East. Although C. sinensis infection can be controlled relatively well using anthelmintics, the worm is carcinogenic, inducing cholangiocarcinoma and causing major suffering in ~15 million people in Asia. This chapter provides an account of C. sinensis and clonorchiasis research-covering aspects of biology, epidemiology, pathogenesis and immunity, diagnosis, treatment and control, genetics and genomics. It also describes progress in the area of molecular biology (genetics, genomics, transcriptomics and proteomics) and highlights challenges associated with comparative genomics and population genetics. It then reviews recent advances in the sequencing and characterisation of the mitochondrial and nuclear genomes for a Korean isolate of C. sinensis and summarises salient comparative genomic work and the implications thereof. The chapter concludes by considering how advances in genomic and informatics will enable research on the genetics of C. sinensis and related parasites, as well as the discovery of new fluke-specific intervention targets. © 2018 Elsevier Ltd All rights reserved.

Rapid Detection and Differentiation of Clonorchis sinensis and Opisthorchis viverrini Using Real-Time PCR and High Resolution Melting Analysis

Directory of Open Access Journals (Sweden)

Xian-Quan Cai

2014-01-01

Full Text Available Clonorchis sinensis and Opisthorchis viverrini are both important fish-borne pathogens, causing serious public health problem in Asia. The present study developed an assay integrating real-time PCR and high resolution melting (HRM analysis for the specific detection and rapid identification of C. sinensis and O. viverrini. Primers targeting COX1 gene were highly specific for these liver flukes, as evidenced by the negative amplification of closely related trematodes. Assays using genomic DNA extracted from the two flukes yielded specific amplification and their identity was confirmed by sequencing, having the accuracy of 100% in reference to conventional methods. The assay was proved to be highly sensitive with a detection limit below 1 pg of purified genomic DNA, 5 EPG, or 1 metacercaria of C. sinensis. Moreover, C. sinensis and O. viverrini were able to be differentiated by their HRM profiles. The method can reduce labor of microscopic examination and the contamination of agarose electrophoresis. Moreover, it can differentiate these two flukes which are difficult to be distinguished using other methods. The established method provides an alternative tool for rapid, simple, and duplex detection of C. sinensis and O. viverrini.

Distribution of freshwater snails in family-based VAC ponds and associated waterbodies with special reference to intermediate hosts of fish-borne zoonotic trematodes in Nam Dinh Province, Vietnam.

Science.gov (United States)

Dung, Bui Thi; Madsen, Henry; The, Dang Tat

2010-10-01

Fish-borne zoonotic trematodes, such as Clonorchis sinensis, heterophyids and others, constitute a public health concern in parts of northern Vietnam and infections with these trematodes are often thought to be linked to fish culture. One common fish culture system is the integrated fish-livestock (VAC) ponds where individual households have 1 or more ponds. Fish fry, mainly of various carp species, produced in hatcheries, not necessarily local, are introduced into nursery ponds and after approximately 6 weeks, juvenile fishes are transferred to household ponds, referred to as grow-out ponds. Grow-out ponds are usually fertilized with organic debris, including animal excreta, to stimulate algal growth and subsequently fish growth. This paper describes the distribution of freshwater snails and occurrence of trematode infections in these in VAC ponds and associated habitats as part of a major study on risk factors of FZT infections in cultured fish in two communes, Nghia Lac and Nghia Phu, Nghia Hung District, Nam Dinh Province. The area is under intense rice cultivation with an extensive canal network supplying fields and also household VAC ponds. A total of 16 snail species was found and four were widely distributed i.e. Angulyagra polyzonata, Melanoides tuberculata, Bithynia fuchsiana and Pomacea insularum. Snail diversity and counts were higher in nursery ponds than in grow-out ponds. Species of the families Thiaridae and Viviparidae were more abundant than other species in VAC ponds while species of the Bithyniidae, Stenothyridae and Planorbidae dominated in rice fields and small canals. Trematode infections were found in eight snail species and among these M. tuberculata had the highest overall prevalence of infection (13.28%). No trematode infections were found in species of the Viviparidae and Ampullaridae except for metacercariae. Parapleurolophocercous and pleurolophocercous cercariae constituted the most common type of cercariae recovered, contributing 40

Private selective sweeps identified from next-generation pool-sequencing reveal convergent pathways under selection in two inbred Schistosoma mansoni strains.

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Julie A J Clément

Full Text Available BACKGROUND: The trematode flatworms of the genus Schistosoma, the causative agents of schistosomiasis, are among the most prevalent parasites in humans, affecting more than 200 million people worldwide. In this study, we focused on two well-characterized strains of S. mansoni, to explore signatures of selection. Both strains are highly inbred and exhibit differences in life history traits, in particular in their compatibility with the intermediate host Biomphalaria glabrata. METHODOLOGY/PRINCIPAL FINDINGS: We performed high throughput sequencing of DNA from pools of individuals of each strain using Illumina technology and identified single nucleotide polymorphisms (SNP and copy number variations (CNV. In total, 708,898 SNPs were identified and roughly 2,000 CNVs. The SNPs revealed low nucleotide diversity (π = 2 × 10(-4 within each strain and a high differentiation level (Fst = 0.73 between them. Based on a recently developed in-silico approach, we further detected 12 and 19 private (i.e. specific non-overlapping selective sweeps among the 121 and 151 sweeps found in total for each strain. CONCLUSIONS/SIGNIFICANCE: Functional annotation of transcripts lying in the private selective sweeps revealed specific selection for functions related to parasitic interaction (e.g. cell-cell adhesion or redox reactions. Despite high differentiation between strains, we identified evolutionary convergence of genes related to proteolysis, known as a key virulence factor and a potential target of drug and vaccine development. Our data show that pool-sequencing can be used for the detection of selective sweeps in parasite populations and enables one to identify biological functions under selection.

Habitat of in vivo transformation influences the levels of free radical scavengers in Clinostomum complanatum: implications for free radical scavenger based vaccines against trematode infections.

Science.gov (United States)

Zafar, Atif; Rizvi, Asim; Ahmad, Irshad; Ahmad, Masood

2014-01-01

Since free radical scavengers of parasite origin like glutathione-S-transferase and superoxide dismutase are being explored as prospective vaccine targets, availability of these molecules within the parasite infecting different hosts as well as different sites of infection is of considerable importance. Using Clinostomum complanatum, as a model helminth parasite, we analysed the effects of habitat of in vivo transformation on free radical scavengers of this trematode parasite. Using three different animal models for in vivo transformation and markedly different sites of infection, progenetic metacercaria of C. complanatum were transformed to adult ovigerous worms. Whole worm homogenates were used to estimate the levels of lipid peroxidation, a marker of oxidative stress and free radical scavengers. Site of in vivo transformation was found to drastically affect the levels of free radical scavengers in this model trematode parasite. It was observed that oxygen availability at the site of infection probably influences levels of free radical scavengers in trematode parasites. This is the first report showing that habitat of in vivo transformation affects levels of free radical scavengers in trematode parasites. Since free radical scavengers are prospective vaccine targets and parasite infection at ectopic sites is common, we propose that infections at different sites, may respond differently to free radical scavenger based vaccines.

Intermediate hosts of the trematode Collyriclum faba (Plagiochiida: Collyriclidae) identified by an integrated morphological and genetic approach

Czech Academy of Sciences Publication Activity Database

Heneberg, P.; Faltýnková, Anna; Bizos, J.; Mala, M.; Žiak, J.; Literák, I.

2015-01-01

Roč. 8, FEB 8 2015 (2015), s. 85 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : cercariae * DNA analysis * fluke * host -parasite interaction * Hydrobiidae * life cycle * Littorinimorpha Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.234, year: 2015

Concomitant prostatic schistosomiasis and sdenocarcinoma: case report and review

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Carlos Alberto Basílio-de-Oliveira

Full Text Available The term schistosomiasis encompasses a group of infectious disorders caused by five species of the genus Schistosoma, a blood trematode of outstanding importance in tropical areas. Some of these disorders have long been associated with malignant neoplasia, the most striking association being between disease caused by Schistosoma haematobium, the predominant etiological agent of urinary schistosomiasis, and squamous cell carcinoma of the bladder, a relatively uncommon vesical cancer in non-endemic areas. Four cases of simultaneous adenocarcinoma and schistosomiasis of the prostate have been previously reported (S. haematobium in three and S. mansoni in one. We report a fifth case of concomitant adenocarcinoma and schistosomiasis of the prostate in a 68-year-old Brazilian patient infected with S. mansoni. We also review the medical literature on the association between schistosomiasis and cancer.

Epidemiology of cercarial stage of trematodes in freshwater snails from Chiang Mai province, Thailand.

Science.gov (United States)

Chontananarth, Thapana; Wongsawad, Chalobol

2013-03-01

To investigate the epidemiological situation of cercarial trematodes infection in freshwater snails from different water resources in Chiang Mai province, Thailand. The snail specimens were collected from 13 districts of Chiang Mai province during April 2008 to February 2012. The prevalence of cercarial infection in snails was investigated using the crushing method. The drawing was done with the help of a camera lucida for the morphological study. A total of 2 479 snail individuals were collected and classified into 7 families, 11 genera, and 14 species, Among them, 8 snails species were found to be infected with an overall prevalence of 17.27% (428/2 479), which infected with nine groups of cercariae; gymnocephalous cercaria, strigea cercaria, megalurous cercaria, monostome cercaria, parapleurolophocercous cercaria (Haplorchis cercaria), pleurolophocercous cercaria, furcocercous cercaria (Transversotrema cercaria), xiphidiocercaria, and virgulate cercaria. The parapleurolophocercous cercaria was found to be the dominant type among the cercarial infection in the snails (64.25%). The various species of snails found in the research location act as the intermediate hosts for the high prevalence of parasitic infection of many species of mammals. This work will provide new information on both the distribution and first intermediate host of trematodes.

Developmental Transcriptomic Features of the Carcinogenic Liver Fluke, Clonorchis sinensis

Science.gov (United States)

Cho, Pyo Yun; Kim, Tae Im; Cho, Shin-Hyeong; Choi, Sang-Haeng; Park, Hong-Seog; Kim, Tong-Soo; Hong, Sung-Jong

2011-01-01

Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs). Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development, bile chemotaxis, and

Developmental transcriptomic features of the carcinogenic liver fluke, Clonorchis sinensis.

Directory of Open Access Journals (Sweden)

Won Gi Yoo

2011-06-01

Full Text Available Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs. Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development

A complete Holocene record of trematode-bivalve infection and implications for the response of parasitism to climate change.

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Huntley, John Warren; Fürsich, Franz T; Alberti, Matthias; Hethke, Manja; Liu, Chunlian

2014-12-23

Increasing global temperature and sea-level rise have led to concern about expansions in the distribution and prevalence of complex-lifecycle parasites (CLPs). Indeed, numerous environmental variables can influence the infectivity and reproductive output of many pathogens. Digenean trematodes are CLPs with intermediate invertebrate and definitive vertebrate hosts. Global warming and sea level rise may affect these hosts to varying degrees, and the effect of increasing temperature on parasite prevalence has proven to be nonlinear and difficult to predict. Projecting the response of parasites to anthropogenic climate change is vital for human health, and a longer term perspective (10(4) y) offered by the subfossil record is necessary to complement the experimental and historical approaches of shorter temporal duration (10(-1) to 10(3) y). We demonstrate, using a high-resolution 9,600-y record of trematode parasite traces in bivalve hosts from the Holocene Pearl River Delta, that prevalence was significantly higher during the earliest stages of sea level rise, significantly lower during the maximum transgression, and statistically indistinguishable in the other stages of sea-level rise and delta progradation. This stratigraphic paleobiological pattern represents the only long-term high-resolution record of pathogen response to global change, is consistent with fossil and recent data from other marine basins, and is instructive regarding the future of disease. We predict an increase in trematode prevalence concurrent with anthropogenic warming and marine transgression, with negative implications for estuarine macrobenthos, marine fisheries, and human health.

Developmental stages of fish blood flukes, Cardicola forsteri and Cardicola opisthorchis (Trematoda: Aporocotylidae), in their polychaete intermediate hosts collected at Pacific bluefin tuna culture sites in Japan.

Science.gov (United States)

Ogawa, Kazuo; Shirakashi, Sho; Tani, Kazuki; Shin, Sang Phil; Ishimaru, Katsuya; Honryo, Tomoki; Sugihara, Yukitaka; Uchida, Hiro'omi

2017-02-01

Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An optimised multi-host trematode life cycle: fishery discards enhance trophic parasite transmission to scavenging birds

Czech Academy of Sciences Publication Activity Database

Born-Torrijos, A.; Poulin, R.; Pérez-del-Olmo, A.; Culurgioni, J.; Raga, J. A.; Holzer, Astrid S.

2016-01-01

Roč. 46, č. 1 (2016), s. 745-753 ISSN 0020-7519 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Cardiocephaloides longicollis * fishery discards * human-induced impact * host specificity * Mediterranean * trematodes Subject RIV: EG - Zoology Impact factor: 3.730, year: 2016

The repertoire of G protein-coupled receptors in the human parasite Schistosoma mansoni and the model organism Schmidtea mediterranea

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Zamanian Mostafa

2011-12-01

Full Text Available Abstract Background G protein-coupled receptors (GPCRs constitute one of the largest groupings of eukaryotic proteins, and represent a particularly lucrative set of pharmaceutical targets. They play an important role in eukaryotic signal transduction and physiology, mediating cellular responses to a diverse range of extracellular stimuli. The phylum Platyhelminthes is of considerable medical and biological importance, housing major pathogens as well as established model organisms. The recent availability of genomic data for the human blood fluke Schistosoma mansoni and the model planarian Schmidtea mediterranea paves the way for the first comprehensive effort to identify and analyze GPCRs in this important phylum. Results Application of a novel transmembrane-oriented approach to receptor mining led to the discovery of 117 S. mansoni GPCRs, representing all of the major families; 105 Rhodopsin, 2 Glutamate, 3 Adhesion, 2 Secretin and 5 Frizzled. Similarly, 418 Rhodopsin, 9 Glutamate, 21 Adhesion, 1 Secretin and 11 Frizzled S. mediterranea receptors were identified. Among these, we report the identification of novel receptor groupings, including a large and highly-diverged Platyhelminth-specific Rhodopsin subfamily, a planarian-specific Adhesion-like family, and atypical Glutamate-like receptors. Phylogenetic analysis was carried out following extensive gene curation. Support vector machines (SVMs were trained and used for ligand-based classification of full-length Rhodopsin GPCRs, complementing phylogenetic and homology-based classification. Conclusions Genome-wide investigation of GPCRs in two platyhelminth genomes reveals an extensive and complex receptor signaling repertoire with many unique features. This work provides important sequence and functional leads for understanding basic flatworm receptor biology, and sheds light on a lucrative set of anthelmintic drug targets.

Schistosoma mansoni mucin gene (SmPoMuc expression: epigenetic control to shape adaptation to a new host.

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Cecile Perrin

Full Text Available The digenetic trematode Schistosoma mansoni is a human parasite that uses the mollusc Biomphalaria glabrata as intermediate host. Specific S. mansoni strains can infect efficiently only certain B. glabrata strains (compatible strain while others are incompatible. Strain-specific differences in transcription of a conserved family of polymorphic mucins (SmPoMucs in S. mansoni are the principle determinants for this compatibility. In the present study, we investigated the bases of the control of SmPoMuc expression that evolved to evade B. glabrata diversified antigen recognition molecules. We compared the DNA sequences and chromatin structure of SmPoMuc promoters of two S. mansoni strains that are either compatible (C or incompatible (IC with a reference snail host. We reveal that although sequence differences are observed between active promoter regions of SmPoMuc genes, the sequences of the promoters are not diverse and are conserved between IC and C strains, suggesting that genetics alone cannot explain the evolution of compatibility polymorphism. In contrast, promoters carry epigenetic marks that are significantly different between the C and IC strains. Moreover, we show that modifications of the structure of the chromatin of the parasite modify transcription of SmPoMuc in the IC strain compared to the C strain and correlate with the presence of additional combinations of SmPoMuc transcripts only observed in the IC phenotype. Our results indicate that transcription polymorphism of a gene family that is responsible for an important adaptive trait of the parasite is epigenetically encoded. These strain-specific epigenetic marks are heritable, but can change while the underlying genetic information remains stable. This suggests that epigenetic changes may be important for the early steps in the adaptation of pathogens to new hosts, and might be an initial step in adaptive evolution in general.

Variable infection of stream salamanders in the southern Appalachians by the trematode Metagonimoides oregonensis (family: Heterophyidae)

Science.gov (United States)

Jennie A. Wyderko; Ernest F. Benfield; John C. Maerz; Kristen C. Cecala; Lisa K. Belden

2015-01-01

Many factors contribute to parasites varying in host specificity and distribution among potential hosts. Metagonimoides oregonensis is a digenetic trematode that uses stream-dwelling plethodontid salamanders as second intermediate hosts in the Eastern US. We completed a field survey to identify which stream salamander species, at a regional level, are most...

Survey of gastrointestinal parasites, liver flukes and lungworm in feces from dairy cattle in the high tropics of Antioquia, Colombia

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Jenny J. Chaparro

2016-06-01

Full Text Available A cross sectional study was undertaken to determine the prevalence and intensity of parasitic infections in dairy cattle in the high tropics of Colombia. A total of 1003 rectal samples were collected from dairy cows at 29 farms between May and June 2014 to represent the number of farms, age groups, and size of the 65,000-cow population in the municipality of San Pedro de los Milagros. Coprological techniques were used to detect gastrointestinal nematodes, liver flukes, coccidian oocysts, and first larval stage counts of Dictyocaulus viviparus. In order of decreasing prevalence, the following parasites were detected: coccidial oocyst (36.7%; 95% CIs, 31.6–42.7, strongyle nematodes (31.6%, 27.8–35.4, liver flukes (30.9%, 21.5–37.5, cestodes (8.4%, 7.1–9.7, and D. viviparus (5.4%, 3.4–7.5. Co-infections by all possible combinations of the three most predominant groups occurred in 11 to 15% of the animals. There were significant differences in infection rates between age groups, with higher risk of liver fluke infection in animals older than 1 year of age (odds ratio (OR = 3.2, but lower presence for coccidia and strongyles (OR = 0.19 and 0.51, respectively. For Fasciola hepatica, within-herd prevalences of >25% in 16 farms and 94 of 281 (33.5% animals with >5 eggs per gram (epg indicate that significant production losses are likely occurring. The variation in the prevalence of gastrointestinal parasites and liver flukes, together with the level of infection among age groups, could be used in integrated management programs to establish selective anthelmintic treatments and select for heritable traits of host resistance. These results serve as a baseline for future studies to determine the success of control measures and should increase awareness that subclinical parasitism is widespread in the livestock sector.

The monomeric orphan nuclear receptor Schistosoma mansoni Ftz-F1 dimerizes specifically and functionally with the schistosome RXR homologue, SmRXR1

International Nuclear Information System (INIS)

Bertin, Benjamin; Caby, Stephanie; Oger, Frederik; Sasorith, Souphatta; Wurtz, Jean-Marie; Pierce, Raymond J.

2005-01-01

In an attempt to understand development and differentiation processes of the parasitic blood fluke Schistosoma mansoni, several members of the nuclear receptor superfamily were cloned, including SmFtz-F1 (S. mansoni Fushi Tarazu-factor 1). The Ftz-F1 nuclear receptor subfamily only contains orphan receptors that bind to their response element as monomers. Whereas SmFtz-F1 displays these basic functional properties, we have identified an original and specific interaction between SmFtz-F1 and the schistosome RXR homologue, SmRXR1. The mammalian two-hybrid assay showed that the D, E, and F domains of SmFtz-F1 were capable of interacting specifically with the E domain of SmRXR1 but not with that of mouse RXRα. Using three-dimensional LBD homology modelling and structure-guided mutagenesis, we were able to demonstrate the essential role of exposed residues located in the dimerization interfaces of both receptors in the maintenance of the interaction. Cotransfection experiments with constructions encoding full-length nuclear receptors show that SmRXR1 potentiates the transcriptional activity of SmFtz-F1 from various promoters. Nevertheless, the lack of identification of a dimeric response element for this SmFtz-F1/SmRXR1 heterodimer seems to indicate a 'tethering' mechanism. Thus, our results suggest for the first time that a member of the Ftz-F1 family could heterodimerize functionally with a homologue of the universal heterodimerization partner of nuclear receptors. This unique property confirms that SmFtz-F1 may be involved in the development and differentiation of schistosome-specific structures

Trematode maturation patterns in a migratory snail host: What happens during upshore residency in a Mediterranean lagoon?

Czech Academy of Sciences Publication Activity Database

Born-Torrijos, A.; Raga, J. A.; Holzer, Astrid S.

2016-01-01

Roč. 115, č. 2 (2016), s. 575-585 ISSN 0932-0113 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : larval maturation * snail migration * Trematodes * Cainocreadium labracis * Macvicaria obovata * Mediterranean lagoon Subject RIV: EG - Zoology Impact factor: 2.329, year: 2016

Evolution of sarcoma 180 (ascitic tumor in mice infected with Schistosoma mansoni

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Fausto Edmundo Lima Pereira

1986-03-01

Full Text Available Mice infected with 60 cercariae of Schistosoma mansoni were more resistant to the sarcoma 180 ascites tumor. Tumor inoculation was performed 50 days after schistosoma infection and the animals were observed and weighed at 48 hours intervals for development and progression of malignancy. In infected mice the weight gain (ascites formation started later and was shorter than in uninfected Controls. Also, the number of tumor cells into the peritoneal cavity 72h after tumor implantation was shorter in infected group than incontrols. This in creased resistance against a transplantable tumor probably is related to the effect of endotoxin on tumoricidal activity of macrophages activated by the infection. The immunodepression induced by Schistosoma mansoni infection enhances the proliferation of endogenous bacteria increasing the amount of endotoxin absorbed from the gut.Camundongos infectados com 60 cercárias de Schistosoma mansoni tomaram-se mais resistentes ao sarcoma 180 na forma de tumor ascítico. A inoculação das células tumorais foi feita no 50º dia de infecção e a evolução do tumor foi acompanhada através dapesagem dos animais com intervalos de 48 horas. Nos camundongos infectados o ganho de peso (formação da ascite começou mais tarde e foi menor do que nos controles não infectados. Também o número de células tumorais na cavidade peritoneal 72 horas após a implantação do tumor foi menor no grupo infectado. Este aumento de resistência a um tumor transplantávelpossivelmente está relacionado ao efeito de endotoxinas sobre a atividade tumoricida dos macrofagos ativados pela infecção. A imunossupressão induzida pela infecção favorece a proliferação de bactérias da flora endógena aumentando a quantidade de endotoxinas absorvidas pelo intestino.

Are sick individuals weak competitors? Competitive ability of snails parasitized by a gigantism-inducing trematode.

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Otto Seppälä

Full Text Available Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability. We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability.

Excretion/secretion products from Schistosoma mansoni adults, eggs and schistosomula have unique peptidase specificity profiles

Czech Academy of Sciences Publication Activity Database

Dvořák, Jan; Fajtová, P.; Ulrychová, L.; Leontovyc, A.; Rojo-Arreola, L.; Suzuki, B.M.; Horn, M.; Mareš, M.; Craik, C. S.; Caffrey, C. R.; O'Donoghue, A.J.

2016-01-01

Roč. 122, MAR (2016), s. 99-109 ISSN 0300-9084 Institutional support: RVO:60077344 Keywords : parasite * fluke * secretion * excretion * protease * inhibitor Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.112, year: 2016

Fishborne trematodes in cultured Nile tilapia (Oreochromis niloticus) and wild-caught fish from Thailand

DEFF Research Database (Denmark)

Wiriya, Benjamaporn; Clausen, Jesper Hedegaard; Inpankaew, Tawin

2013-01-01

Fish-borne zoonotic trematode (FZT) infections affect the health of more than 18 million people around the world, particularly in Asian countries. Nile tilapia (Oreochromis niloticus) is a white meat fish that has an increasing national and international market. The objective of this study was to...... for vigilance and good management practices by the aquaculture sector. Crown...

Effects of Mirazid Treatment and Vaccination with Irradiated Cercariae in Experimentally Schistosoma mansoni Infected Mice

International Nuclear Information System (INIS)

Fayad, M.E.; Moawad, M.A.; Abd El-Fattah, N.Se.

2006-01-01

Schistosomiasis Tops all the endemic parasitic diseases particularly in Egypt. This study was performed on 4 groups of mice, each group formed of 25 mice. Group 1 (control group) infected with Schistosoma mansoni cercariae, group 2 (vaccinated group) vaccinated with irradiated cercariae, group 3 (treated group) infected with living cercariae of Schistosoma mansoni, then treated with Mirazid in the day post infection and group 4 (vaccinated and treated group) vaccinated with irradiated cercariae of Schistosoma mansoni then challenged and treated with Mirazid in the day post infection. By comparing the results of group 4 (vaccinated and treated group) with respective control there was a highly significant difference in all parameters. The worm burden reduction was 100 % and the percentage reduction of the eggs in the liver was 96.6 % and in the intestine was 89.76 %. Also, there were marked reduction in the size and number of granulomas with preservation of the liver architecture and absence of areas of degeneration and necrosis. So, this study shown that resistance to schistosomiasis can be consistently induced in mice by combining drug therapy with vaccination

The schistosoma-specific antibody response after treatment in non-immune travellers

DEFF Research Database (Denmark)

Duus, Liv Marie; Christensen, Anders Vittrup; Navntoft, Dorte

2009-01-01

Egg detection is the gold standard in diagnosing and controlling treatment in schistosomiasis, but sensitivity is poor in lightly infected individuals, whereas Schistosoma-specific antibodies are more sensitive. The purpose of the study was to evaluate use of Gut Associated Antigen (GAA...

Rapid colonisation of Lymnaea stagnalis by larval trematodes in eutrophic ponds in central Europe

Czech Academy of Sciences Publication Activity Database

Soldánová, Miroslava; Kostadinova, Aneta

2011-01-01

Roč. 41, č. 9 (2011), 981-990 ISSN 0020-7519 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lymnaea stagnalis * Freshwater pulmonate snail * Larval trematodes * Colonisation and extinction * Competition-colonisation trade-off * Eutrophic ponds * Central Europe Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.393, year: 2011

Molecular identification of Clonorchis sinensis and discrimination with other opisthorchid liver fluke species using Multiple Ligation-dependent Probe Amplification (MLPA).

NARCIS (Netherlands)

Sun, J.; Xu, J.; Liang, P.; Mao, Q.; Huang, Y.; Lu, X.; Deng, C.; Liang, C.; de Hoog, G.S.; Yu, X.

2011-01-01

Background Infections with the opisthorchid liver flukes Clonorchis sinensis, Opisthorchis viverrini, and O. felineus cause severe health problems globally, particularly in Southeast Asia. Early identification of the infection is essential to provide timely and appropriate chemotherapy to patients.

Morfologia e desenvolvimento de Schistosoma mansoni Sambon, 1907 em infecções unissexuais experimentalmente produzidas no camundongo Morphology and development of Schistosoma mansoni Sambon, 1907 in unisexual infections produced experimentally in mice

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Eliana Maria Zanotti

1982-04-01

Full Text Available Estudou-se o desenvolvimento de Schistosoma mansoni em infecções unissexuais no camundongo. Os esquistossomos fêmeos apresentaram-se menos desenvolvidos do que os machos. Houve correlação entre o comprimento dos machos e o número de testículos. Verificou-se que o isolamento sexual é prejudicial aos dois sexos, principalmente à fêmea.The Schistosoma mansoni development in mice submitted to unisexual infections was studied. The single female worms developed less than the single males. There was correlation between the male's length and the number of his tests. It was verified that sexual isolation of the schistosomes is prejudicial to both sexes, mainly for the female.

In vitro antihelmintic effect of fifteen tropical plant extracts on excysted flukes of Fasciola hepatica

OpenAIRE

Alvarez-Mercado, Jos? Manuel; Ibarra-Velarde, Froyl?n; Alonso-D?az, Miguel ?ngel; Vera-Montenegro, Yolanda; Avila-Acevedo, Jos? Guillermo; Garc?a-Bores, Ana Mar?a

2015-01-01

Background Fasciolosis due to Fasciola hepatica is the most important hepatic disease in veterinary medicine. Its relevance is important because of the major economical losses to the cattle industry such as: reduction in milk, meat and wool production; miscarriages, anemia, liver condemnation and occasionally deaths, are estimated in billons of dollars. The emergence of fluke resistance due to over or under dosing of fasciolides as well as environmental damage produced by the chemicals elimin...

Pathological and molecular studies of the renal trematode Paratanaisia bragai in Indian peafowls (Pavo cristatus).

Science.gov (United States)

Asok Kumar, M; Kumar, Deepak; Palanivelu, Munuswamy; Annamalai, Latchumikanthan; Mathesh, Karikalan; Singh, Rajendra; Sharma, Anil Kumar; Dhama, Kuldeep

2018-03-26

Endoparasitic diseases are commonly encountered in free-ranging birds. Although not all endoparasites cause disease, persistent infection with large numbers of parasites almost always affects normal physiological functions, leading to deleterious effects on the host. This paper describes the anatomopathological alterations caused by the renal trematode Paratanaisia bragai in Indian peafowl (n = 3) and examines the phylogeny of these and related parasites. Peafowl from forests in and around the Bareilly region, Uttar Pradesh, India, were necropsied, and microscopic and molecular investigations were performed. The peafowl were confirmed to be infected with P. bragai. Significant gross pathological lesions suggested nephrosis, and microscopic findings indicated a mild-to-moderate degree of nephrosis caused by the parasites in the tissue. The parasites were identified as P. bragai by histomorphological analysis of adult and eggs in the ureters, and the identification was confirmed by PCR and phylogenetic analysis. Nucleotide sequencing of the PCR products from the renal trematodes recovered from Indian peafowl revealed a close association with P. bragai from Columbiformes in the United Kingdom and Spain. The pathology and molecular epidemiology of parasitic diseases affecting peafowl is not well understood in India. This is the first report from India and the second report worldwide to document P. bragai infection in peafowl.

State-space forecasting of Schistosoma haematobium time-series in Niono, Mali.

Science.gov (United States)

Medina, Daniel C; Findley, Sally E; Doumbia, Seydou

2008-08-13

Much of the developing world, particularly sub-Saharan Africa, exhibits high levels of morbidity and mortality associated with infectious diseases. The incidence of Schistosoma sp.-which are neglected tropical diseases exposing and infecting more than 500 and 200 million individuals in 77 countries, respectively-is rising because of 1) numerous irrigation and hydro-electric projects, 2) steady shifts from nomadic to sedentary existence, and 3) ineffective control programs. Notwithstanding the colossal scope of these parasitic infections, less than 0.5% of Schistosoma sp. investigations have attempted to predict their spatial and or temporal distributions. Undoubtedly, public health programs in developing countries could benefit from parsimonious forecasting and early warning systems to enhance management of these parasitic diseases. In this longitudinal retrospective (01/1996-06/2004) investigation, the Schistosoma haematobium time-series for the district of Niono, Mali, was fitted with general-purpose exponential smoothing methods to generate contemporaneous on-line forecasts. These methods, which are encapsulated within a state-space framework, accommodate seasonal and inter-annual time-series fluctuations. Mean absolute percentage error values were circa 25% for 1- to 5-month horizon forecasts. The exponential smoothing state-space framework employed herein produced reasonably accurate forecasts for this time-series, which reflects the incidence of S. haematobium-induced terminal hematuria. It obliquely captured prior non-linear interactions between disease dynamics and exogenous covariates (e.g., climate, irrigation, and public health interventions), thus obviating the need for more complex forecasting methods in the district of Niono, Mali. Therefore, this framework could assist with managing and assessing S. haematobium transmission and intervention impact, respectively, in this district and potentially elsewhere in the Sahel.

Polymorphic microsatellites in the human bloodfluke, Schistosoma japonicum, identified using a genomic resource

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Spear Robert

2011-02-01

Full Text Available Abstract Re-emergence of schistosomiasis in regions of China where control programs have ceased requires development of molecular-genetic tools to track gene flow and assess genetic diversity of Schistosoma populations. We identified many microsatellite loci in the draft genome of Schistosoma japonicum using defined search criteria and selected a subset for further analysis. From an initial panel of 50 loci, 20 new microsatellites were selected for eventual optimization and application to a panel of worms from endemic areas. All but one of the selected microsatellites contain simple tri-nucleotide repeats. Moderate to high levels of polymorphism were detected. Numbers of alleles ranged from 6 to 14 and observed heterozygosity was always >0.6. The loci reported here will facilitate high resolution population-genetic studies on schistosomes in re-emergent foci.

Phosphagen kinase in Schistosoma japonicum: characterization of its enzymatic properties and determination of its gene structure.

Science.gov (United States)

Tokuhiro, Shinji; Uda, Kouji; Yano, Hiroko; Nagataki, Mitsuru; Jarilla, Blanca R; Suzuki, Tomohiko; Agatsuma, Takeshi

2013-04-01

Phosphagen kinases (PKs) play a major role in the regulation of energy metabolism in animals. Creatine kinase (CK) is the sole PK in vertebrates, whereas several PKs are present in invertebrates. Here, we report the enzymatic properties and gene structure of PK in the trematode Schistosoma japonicum (Sj). SjPK has a unique contiguous dimeric structure comprising domain 1 (D1) and domain 2 (D2). The three states of the recombinant SjPK (D1, D2, and D1D2) show a specific activity for the substrate taurocyamine. The comparison of the two domains of SjPK revealed that D1 had a high turnover rate (kcat=52.91) and D2 exhibited a high affinity for taurocyamine (Km(Tauro) =0.53±0.06). The full-length protein exhibited higher affinity for taurocyamine (Km(Tauro) =0.47±0.03) than the truncated domains (D1=1.30±0.10, D2=0.53±0.06). D1D2 also exhibited higher catalytic efficiency (kcat/Km(Tauro) =82.98) than D1 (40.70) and D2 (29.04). These results demonstrated that both domains of SjTKD1D2 interacted efficiently and remained functional. The three-dimensional structure of SjPKD1 was constructed by the homology modeling based on the transition state analog complex state of Limulus AK. This protein model of SjPKD1 suggests that the overall structure is almost conserve between SjPKD1 and Limulus AK except for the flexible loops, that is, particularly guanidino-specificity (GS) region, which is associated with the recognition of the corresponding guanidino substrate. The constructed NJ tree and the comparison of exon/intron organization suggest that SjTK has evolved from an arginine kinase (AK) gene. SjTK has potential as a novel antihelminthic drug target as it is absent in mammals and its strong activity may imply a significant role for this protein in the energy metabolism of the parasite. Copyright © 2013 Elsevier B.V. All rights reserved.

Characterization of the cGMP-dependent protein kinase SmcGK1 of Schistosoma mansoni

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Silke Leutner

2011-06-01

Full Text Available Schistosomes are trematode parasites and of worldwide medical importance for humans and animals. Growth and development of these parasites require a specific host environment, but also permanent communication processes between the two genders. Accumulating molecular evidence indicates that the responsible interactions are mediated by signal transduction processes. Conserved signaling molecules were identified, and first approaches made for their characterization. However, no representative of the conserved family of cGMP-dependent protein kinases (cGKs has been described in this parasite yet. Within the Schistosoma mansoni genome data-set we identified cGK homologs, of which one was investigated in more detail in this study. We present the cloning of SmcGK1, whose sequence shows homology to cGKs of higher eukaryotes. SmcGK1 was found to be gender-independently transcribed in adult schistosomes. The occurrence of SmcGK1 sense and antisense transcripts suggests that the expression of this gene is controlled at the post-transcriptional level. In situ hybridization experiments demonstrated a gonad-preferential expression profile in both genders indicating a role of SmcGK1, at least during sexual development of schistosomes. Using a cGK-specific inhibitor to treat adult schistosomes in vitro finally resulted in a multifaceted phenotype including slow motion, oocyte congestion, and reduced egg production.Esquistossomos são parasitas trematodos de importância médica em todo o mundo para o homem e os animais. O crescimento e o desenvolvimento destes parasitas requerem um ambiente específico do hospedeiro, mas também um processo de comunicação permanente entre parasitas dos dois sexos. Evidência molecular tem se acumulado e indica que as interações são mediadas por processos de transdução de sinal. Moléculas sinalizadoras conservadas foram identificadas, e as primeiras abordagens têm sido feitas para sua caracterização. Contudo, não foi

Intestinal schistosomiasis among preschool children along the shores of Lake Victoria in Uganda

DEFF Research Database (Denmark)

Nalugwa, A.; Olsen, Annette; Tukahebwa, M. E.

2015-01-01

Schistosomiasis, a disease caused by Schistosoma trematode parasites, affects hundreds of millions of people and accounts for more than 40% of the global health burden due to neglected tropical diseases. In Uganda, intestinal schistosomiasis is endemic in 73 out of 112 districts and about 55......% of the population of 36 million individuals are at risk. There is scanty information on the status and burden of schistosomiasis in preschool children less than six years of age in Uganda. This study aimed to assess the status of Schistosoma mansoni infections in children aged 1-5 years in Uganda. S. mansoni...... prevalence and intensity of infection were examined in 3058 children from 5 districts along Lake Victoria shoreline, eastern Uganda. For each child one stool sample was collected on three consecutive days. The Kato-Katz technique was used to prepare stool smears on slides for microscopic examination. Short...

Clonorchis sinensis and Opisthorchis spp. in Vietnam: current status and prospects.

Science.gov (United States)

Doanh, Pham N; Nawa, Yukifumi

2016-01-01

Clonorchis sinensis and Opisthorchis viverrini are clinically important small liver flukes because of their known association with development of cholangiocarcinoma. In Vietnam, high prevalence of C. sinensis infection in humans was previously reported in northern provinces, and O. viverrini infection has been detected in several central provinces. However, diagnosis of C. sinensis and O. viverrini infections in the past was merely based on faecal egg examination. This method alone can lead to misidentification at the species level because of morphological similarity between the eggs of these liver flukes and minute intestinal trematodes of the family Heterophyidae. In fact, recent surveys in Vietnam revealed that infection with several minute intestinal flukes, such as Haplorchis pumilio and H. taichui, are much more common than infection with C. sinensis or O. viverrini, and they often co-infect humans. Thus, previously reported prevalence of small liver fluke infection in Vietnam was likely over-estimated due to mis identification of parasites in copro-parasitological examinations. In addition, there is some confusion about identification of cercariae, metacercariae and also adults of C. sinensis and O. viverrini in intermediate and definitive hosts. The aim of this review is, therefore, to draw realistic pictures of the past and present scientific reports on the epidemiology and biology of C. sinensis and Opisthorchis spp. infection in Vietnam. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Glycogen metabolism in Schistosoma mansoni worms after their isolation from the host

NARCIS (Netherlands)

Tiolens, A.G.M.; Bergh, S.G. van den

Adult Schistosoma mansoni worms rapidly degrade their endogenous glycogen stores immediately after isolation from the host. In NCTC 109 or in a diphasic culture medium the glycogen levels slowly recovered again after the initial decrease. The rapid degradation of glycogen could be prevented, even in

Activation route of the Schistosoma mansoni cathepsin B1 drug target

Czech Academy of Sciences Publication Activity Database

Jílková, Adéla; Horn, Martin; Řezáčová, Pavlína; Marešová, Lucie; Fajtová, Pavla; Brynda, Jiří; Vondrášek, Jiří; McKerrow, J. H.; Caffrey, C. R.; Mareš, Michael

2015-01-01

Roč. 22, č. 1 (2015), s. 39 ISSN 1211-5894. [Discussions in Structural Molecular Biology. Annual Meeting of the Czech Society for Structural Biology /13./. 19.03.2015-21.03.2015, Nové Hrady] Institutional support: RVO:61388963 ; RVO:68378050 Keywords : Schistosoma mansoni * cathepsin B1 * sulfated polysaccharides Subject RIV: CE - Biochemistry

Vaccination against schistosomiasis and fascioliasis with the new recombinant antigen Sm14: potential basis of a multi-valent anti-helminth vaccine?

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Miriam Tendler

1995-04-01

Full Text Available Molecular cloning of components of protective antigenic preparations have suggested that related parasite fatty acid binding proteins could form the basis of the well documented protective, immune cross reactivity between the parasitic trematode worms Fasciola hepatica and Schistosoma mansoni. We have now confirmed the cross protective potential of parasite fatty acid binding proteins and suggest that it may be possible to produce a single vaccine that would be effective against at least two parasites, F. hepatica and S. mansoni of veterinary and human importance respectively.

Effects of Endosulfan on Predator–Prey Interactions Between Catfish and Schistosoma Host Snails

NARCIS (Netherlands)

Monde, Concillia; Syampungani, Stephen; Brink, van den Paul J.

2016-01-01

The effect of the pesticide endosulfan on predator–prey interactions between catfish and Schistosoma host snails was assessed in static tank experiments. Hybrid catfish (Clarias gariepinus × C. ngamensis) and Bulinus globosus were subjected to various endosulfan concentrations including an

Effect of gamma-radiation on cercariae of Schistosoma incognitum and S. spindale

Energy Technology Data Exchange (ETDEWEB)

Bhaskara Rao, T; Rao, B V; Hafeez, Md [College of Veterinary Sciences, Tirupati (India). Dept. of Parasitology

1989-06-01

In the present study an attempt has been made to study the effect of gamma radiation on cercariae of Schistosoma incognitum and S. spindale in mice at different dose levels of radiation, so as to note differences in their developmental patterns, compared with non-irradiated controls. (author). 10 refs.

Excretion/secretion products from Schistosoma mansoni adults, eggs and schistosomula have unique peptidase specificity profiles

Czech Academy of Sciences Publication Activity Database

Dvořák, Jan; Fajtová, Pavla; Ulrychová, L.; Leontovyč, Adrian; Rojo-Arreola, L.; Suzuki, B.M.; Horn, Martin; Mareš, Michael; Craik, C. S.; Caffrey, C. R.; O'Donoghue, A.J.

2016-01-01

Roč. 122, Mar (2016), s. 99-109 ISSN 0300-9084 R&D Projects: GA ČR(CZ) GAP302/11/1481; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : parasite * fluke * secretion * excretion * protease * inhibitor Subject RIV: CE - Biochemistry Impact factor: 3.112, year: 2016

Relationship between snail population density and infection status of snails and fish with zoonotic trematodes in Vietnamese carp nurseries

DEFF Research Database (Denmark)

Clausen, Jesper Hedegaard; Madsen, Henry; Murrell, Kenneth Darwin

2012-01-01

ponds. Previous risk assessment on FZT transmission in the Red River Delta of Vietnam identified carp nursery ponds as major sites of transmission. In this study, we analyzed the association between snail population density and heterophyid trematode infection in snails with the rate of FZT transmission...... to juvenile fish raised in carp nurseries....

Fatal trematodiasis in research turtles.

Science.gov (United States)

Johnson, C A; Griffith, J W; Tenorio, P; Hytrek, S; Lang, C M

1998-08-01

During a 5-year period, 16 freshwater turtles (Trachemys scripta elegans and Chrysemys picta) that were purchased for research purposes died spontaneously. Clinical signs of disease included lethargy, constant swimming, swimming sideways, hemiplegia, and ulcerative lesions on the carapace. At necropsy, subcutaneous edema, hepatic necrosis, pancreatic necrosis, splenic necrosis, and intestinal parasites were identified. Histologically, trematode eggs were seen within the liver, brain, spleen, kidney, myocardium, lung, pancreas, testes, and bladder, and were associated with granulomatous reactions. The size and distribution of the eggs were consistent with Spirorchis sp. infection, although adults could not be found to confirm the species. Spirorchid flukes are 1 to 2 mm long and inhabit the heart and blood vessels where they produce eggs. Spirorchis parvus are capable of invading various tissues, including pancreas and the central nervous system. The pathogenicity of the flukes seems to be related to widespread deposition of the eggs, which may block small blood vessels within the intestines, causing necrosis and bacteremia. Antemortem diagnosis is made by direct examination of fecal smears for eggs. Postmortem diagnosis is accomplished by examination of tissues for adult parasites and microgranulomas associated with the fluke eggs. The parasite requires a snail intermediate host to complete its life cycle. Intramuscular or oral administration of praziquantel is reported to be an effective treatment.

Natural infection by Paramphistomoidea Stiles and Goldberger, 1910 trematodes in wild Marsh Deer (Blastocerus dichotomus Illiger, 1815) from Sérgio Mottas's hydroelectric power station flooding area.

Science.gov (United States)

do Nascimento, Cristiano G; do Nascimento, Adjair A; Mapeli, Elaine B; Tebaldi, José H; Duarte, José M B; Hoppe, Estevam G Lux

2006-01-01

Studies on helminthfauna of marsh deer Blastocerus dichotomus Illiger, 1815 are rare, although helminthic diseases are an important cause of mortality in these animals. Fifteen male and female adult marsh deer from Sergio Motta's hydroelectric power station flooding area at Paraná River which died during the capture and quarantine procedures, between 1998 and 1999, were necropsied. Three trematodes species, Paramphistomum cervi, Balanorchis anastrofus and Zygocotyle lunatum, all belonging to superfamily Paramphistomoidea, were identified. The obtained trematodes were identified, counted and their respectives descriptors of infection were determined. All necropsied animals were infected by helminths. Paramphistomum cervi was the most prevalent species, while Zygocotyle lunatum was found in only one animal.

Excretion/secretion products from Schistosoma mansoni adults, eggs and schistosomula have unique peptidase specificity profiles

Czech Academy of Sciences Publication Activity Database

Dvořák, Jan; Fajtová, P.; Ulrychová, Lenka; Leontovyc, A.; Rojo-Arreola, L.; Suzuki, B.M.; Horn, M.; Mareš, M.; Craik, C. S.; Caffrey, C. R.; O'Donoghue, A.J.

2016-01-01

Roč. 122, jaro (2016), s. 99-109 ISSN 0300-9084 R&D Projects: GA ČR(CZ) GAP302/11/1481; GA MŠk LO1302 Institutional support: RVO:68378050 Keywords : Parasite * Fluke * Secretion * Excretion * Protease * Inhibitor Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.112, year: 2016

Freshwater Aquaculture Nurseries and Infection of Fish with Zoonotic Trematodes, Vietnam

Science.gov (United States)

Ersbøll, Annette Kjær; Nguyen, Thanh Thi; Nguyen, Khue Viet; Nguyen, Ha Thi; Murrell, Darwin; Dalsgaard, Anders

2010-01-01

Residents of the Red River Delta region of northern Vietnam have a long tradition of eating raw fish. Fish-borne zoonotic trematodes (FZTs) are estimated to infect ≈1 million persons in Vietnam. It remains uncertain at what stages in the aquaculture production cycle fish become infected with FZTs. Newly hatched fish (fry) from 8 hatcheries and juveniles from 27 nurseries were therefore examined for FZT infection. No FZTs were found in fry from hatcheries. In nurseries, FZT prevalence in juveniles was 14.1%, 48.6%, and 57.8% after 1 week, 4 weeks, and when overwintered in ponds, respectively. FZT prevalence was higher in grass carp (paquaculture management practices, particularly in nurseries, to minimize the risk of distributing infected juveniles to grow-out ponds and, subsequently, to markets for human consumption. PMID:21122220

Genetic diversity of the Chinese liver fluke Clonorchis sinensis from Russia and Vietnam.

Science.gov (United States)

Chelomina, Galina N; Tatonova, Yulia V; Hung, Nguyen Manh; Ngo, Ha Duy

2014-10-01

Clonorchiasis is a parasitic disease of high public health importance in many countries in southeastern Asia and is caused by the Chinese liver fluke Clonorchis sinensis. However, the genetic structure and demographic history of its populations has not been sufficiently studied throughout the geographic range of the species and available data are based mainly on partial gene sequencing. In this study, we explored the genetic diversity of the complete 1560 bp cytochrome c oxidase subunit 1 (cox1) gene sequence for geographically isolated C. sinensis populations in Russia and Vietnam, to our knowledge for the first time. The results demonstrated low nucleotide and high haplotype differentiation within and between the two compared regions and a clear geographical vector for the distribution of genetic diversity patterns among the studied populations. These results suggest a deep local adaptation of the parasite to its environment including intermediate hosts and the existence of gene flow across the species' range. Additionally, we have predicted an amino acid substitution in the functional site of the COX1 protein among the Vietnamese populations, which were reported to be difficult to treat with praziquantel. The haplotype networks consisted of several region-specific phylogenetic lineages, the formation of which could have occurred during the most extensive penultimate glaciations in the Pleistocene Epoch. The patterns of genetic diversity and demographics are consistent with population growth of the liver fluke in the late Pleistocene following the Last Glacial Maximum, indicating the lack of a population bottleneck during the recent past in the species' history. The data obtained have important implications for understanding the phylogeography of C. sinensis, its host-parasite interactions, the ability of this parasite to evolve drug resistance, and the epidemiology of clonorchiasis under global climate change. Copyright © 2014 Australian Society for

A population growth trend analysis for Neotricula aperta, the snail intermediate host of Schistosoma mekongi, after construction of the Pak-Mun dam.

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Stephen W Attwood

2013-11-01

Full Text Available The Pak-Mun dam is a controversial hydro-power project on the Mun River in Northeast Thailand. The dam is sited in a habitat of the freshwater snail Neotricula aperta, which is the intermediate host for the parasitic blood-fluke Schistosoma mekongi causing Mekong schistosomiasis in humans in Cambodia and Laos. Few data are available which can be used to assess the effects of water resource development on N. aperta. The aim of this study was to obtain data and to analyze the possible impact of the dam on N. aperta population growth.Estimated population densities were recorded for an N. aperta population in the Mun River 27 km upstream of Pak-Mun, from 1990 to 2011. The Pak-Mul dam began to operate in 1994. Population growth was modeled using a linear mixed model expression of a modified Gompertz stochastic state-space exponential growth model. The N. aperta population was found to be quite stable, with the estimated growth parameter not significantly different from zero. Nevertheless, some marked changes in snail population density were observed which were coincident with changes in dam operation policy.The study found that there has been no marked increase in N. aperta population growth following operation of the Pak-Mun dam. The analysis did indicate a large and statistically significant increase in population density immediately after the dam came into operation; however, this increase was not persistent. The study has provided the first vital baseline data on N. aperta population behavior near to the Pak-Mun dam and suggests that the operation policy of the dam may have an impact on snail population density. Nevertheless, additional studies are required for other N. aperta populations in the Mun River and for an extended time series, to confirm or refine the findings of this work.

Organomegaly in Mali before and after praziquantel treatment. A possible association with Schistosoma haematobium

DEFF Research Database (Denmark)

Stecher, Chalotte Willemann; Madsen, Henry; Wilson, Shona

2017-01-01

Continuous exposure to schistosome-infested water results in acute and chronic morbidity in all ages. We analysed occurence of organomegaly via ultrasonography and investigated a possible additive effect of dual-dose drug administration in 401 Schistosoma haematobium infected individuals from...

Whole-genome in-silico subtractive hybridization (WISH - using massive sequencing for the identification of unique and repetitive sex-specific sequences: the example of Schistosoma mansoni

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Parrinello Hugues

2010-06-01

Full Text Available Abstract Background Emerging methods of massive sequencing that allow for rapid re-sequencing of entire genomes at comparably low cost are changing the way biological questions are addressed in many domains. Here we propose a novel method to compare two genomes (genome-to-genome comparison. We used this method to identify sex-specific sequences of the human blood fluke Schistosoma mansoni. Results Genomic DNA was extracted from male and female (heterogametic S. mansoni adults and sequenced with a Genome Analyzer (Illumina. Sequences are available at the NCBI sequence read archive http://www.ncbi.nlm.nih.gov/Traces/sra/ under study accession number SRA012151.6. Sequencing reads were aligned to the genome, and a pseudogenome composed of known repeats. Straightforward comparative bioinformatics analysis was performed to compare male and female schistosome genomes and identify female-specific sequences. We found that the S. mansoni female W chromosome contains only few specific unique sequences (950 Kb i.e. about 0.2% of the genome. The majority of W-specific sequences are repeats (10.5 Mb i.e. about 2.5% of the genome. Arbitrarily selected W-specific sequences were confirmed by PCR. Primers designed for unique and repetitive sequences allowed to reliably identify the sex of both larval and adult stages of the parasite. Conclusion Our genome-to-genome comparison method that we call "whole-genome in-silico subtractive hybridization" (WISH allows for rapid identification of sequences that are specific for a certain genotype (e.g. the heterogametic sex. It can in principle be used for the detection of any sequence differences between isolates (e.g. strains, pathovars or even closely related species.

Prevalence of infection and molecular confirmation by using ITS-2 region of Fasciola gigantica found in domestic cattle from Chiang Mai province, Thailand.

Science.gov (United States)

Phalee, Anawat; Wongsawad, Chalobol

2014-03-01

To investigate the infection of Fasciola gigantica (F. gigantica) in domestic cattle from Chiang Mai province and molecular confirmation using ITS-2 region. The liver and gall bladder of Bubalus bubalis (B. bubalis) and Bos taurus (B. taurus) from slaughterhouses were examined adult worms and prevalence investigation. The species confirmation with phylogenetic analysis using ITS-2 sequences was performed by maximum likelihood and UPGMA methods. The total prevalences of infection in B. bubalis and Bubalus taurus (B. taurus) were 67.27% and 52.94% respectively. The respective prevalence in both B. bubalis and B. taurus were acquired from Doi-Saket, Muang, and Sanpatong districts, with 81.25%, 62.50% and 60.00% for B. bubalis and 62.50%, 50.00% and 47.06% for Bos taurus respectively. The species confirmation of F. gigantica and some related species by basing on maximum likelihood and UPGMA methods used, 4 groups of trematodes were generated, first F. gigantica group including specimen of Chiang Mai, second 2 samples of F. hepatica, third group of 3 rumen flukes; Orthocoelium streptocoelium, F. elongatus and Paramphistomum epliclitum and fourth group of 3 minute intestinal flukes; Haplorchis taichui, Stellantchasmu falcatus, Haplorchoides sp. and liver fluke; Opisthorchis viverrini respectively. These results can be confirmed the Giant liver fluke which mainly caused fascioliasis in Chiang Mai was identified as F. gigantica and specimens were the same as those of F. gigantica recorded in other different countries. Nucleotide sequence of ITS-2 region has been proven as effective diagnostic tool for the identification of F. gigantica. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Blood flukes (Digenea: Aporocotylidae) of walking catfishes (Siluriformes: Clariidae): new genus and species from the Mekong River (Vietnam) with comments on related catfish aporocotylids.

Science.gov (United States)

Truong, Triet Nhat; Bullard, Stephen A

2013-07-01

Nomasanguinicola canthoensis gen. et sp. n. infects the branchial vessels of bighead catfish, Clarias macrocephalus Günther (Siluriformes: Clariidae), in the Mekong River near Can Tho, southern Vietnam. Nomasanguinicola differs from all other genera of fish blood flukes (Digenea: Aporocotylidae) by the combination of lacking body spines and by having an anterior sucker with two flanking columns of large denticles, an intestine comprising several short papilla-like caeca, an inverse U-shaped uterus, and an ootype located near the separate genital pores. The new species has an ootype that is posterior to the level of the female genital pore. That feature most easily differentiates it from the only other putative aporocotylid species having an anterior sucker with two flanking columns of large denticles, Plehniella dentata Paperna, 1964 and Sanguinicola clarias Imam, Marzouk, Hassan et Itman, 1984, which have an ootype that is lateral (P. dentata) or anterior (S. clarias) to the level of the female genital pore. These two species apparently lack extant type materials, infect North African catfish, Clarias gariepinus (Burchell), and herein are considered incertae sedis, but likely comprise species of Nomasanguinicola. An updated list of hosts, sites of infection and geographic localities for the six species and three genera of blood flukes that mature in catfishes is provided. The new species is the first fish blood fluke recorded from Vietnam and only the third reported from a walking catfish (Clariidae).

Feeding behavior of black carp Mylopharyngodon piceus (Pisces: Cyprinidae) on fry of other fish species and trematode transmitting snail species

DEFF Research Database (Denmark)

Hung, Nguyen Manh; The, Dang Tat; Stauffer, Jay R.

2014-01-01

Fish raised in aquaculture ponds may get infected with fishborne zoonotic trematodes (FZT) during the nursing stage. Freshwater snails serve as intermediate hosts for FZT and we wanted to explore the possibility of controlling snails by stocking nursery ponds with a few juvenile specimens...

Detection of the circulating antigen 14-3-3 protein of Schistosoma japonicum by time-resolved fluoroimmunoassay in rabbits

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Wang Jie

2011-05-01

Full Text Available Abstract Background Schistosomiasis remains a major public health concern that afflicts millions of people worldwide. Low levels of Schistosoma infection require more sensitive diagnostic methods. In this study, a time-resolved fluoroimmunoassay (TRFIA was developed for detecting the signal transduction protein 14-3-3, a circulating antigen of Schistosoma japonicum. Results The detection limit of 14-3-3-TRFIA was 0.78 ng/ml, with a linear measurement range from 0.78 to 800 ng/ml. The average intra-assay and inter-assay variability of this TRFIA was 8.9% and 12.2% respectively, and the mean recovery rate ranged from 92.1% to 115.5%. Within the first 21 days post-infection in rabbits, the positive rates of the 14-3-3-TRFIA were distinctly higher compared to ELISA. All these findings illustrate that 14-3-3-TRFIA has a higher detection efficacy and is a good early diagnostic method for active Schistosoma infection. Conclusions A sandwich TRFIA for detecting the circulating antigen 14-3-3 of S. japonicum has been developed, and has demonstrated to be a good potential diagnostic method for schistosomiasis.

Molecular confirmation of trematodes in the snail intermediate hosts from Ratchaburi Province, Thailand

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Sothorn Anucherngchai

2017-05-01

Full Text Available Objective: To analyze the prevalence of trematode infections in the snails intermediate host Tarebia granifera and Melanoides tuberculata collected from Ratchaburi Province by a molecular approach in order to construct a dendrogram to identify species at the cercarial stage. Methods: Specimens were collected from nine districts located in Ratchaburi Province using the stratified sampling method. The samples were examined for cercarial infection using the crushing method. All specimens were amplified by region of internal transcribed spacer 2 (ITS2 based on the PCR technique, and the sequence data were aligned in order to construct the dendrogram by maximum likelihood with 10 000 bootstrap replicates. Results: Five cercarial types were observed comprising parapleurolophocercous cercaria, xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria. The overall prevalence of cercarial infection was found to be 7.92% (63 / 795. The parapleurolophocercous cercaria was found in the highest level of prevalence followed by xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria, respectively. The parapleurolophocercous cercaria samples were identified and separated into Haplorchis taichui and Haplorchis pumilio, while xiphidiocercaria were identified as Lecithodendriidae and megarulous cercaria were identified as Philophthalmus. The dendrogram separated the cercariae into five groups, which were comprised of parapleurolophocercous cercaria, xiphidiocercaria, megarulous cercaria, furcocercous cercaria and transversotrema cercaria using the sequence of Angiostrongylus cantonensis as an out-group. Conclusions: This is the first study to report on the prevalence of cercarial infection in Ratchaburi Province, Thailand. The high prevalence of cercariae was revealed by the infection in Tarebia granifera and Melanoides tuberculata. Thus, the sequence data of ITS2 can be used to investigate the

Parasites in a man-made landscape: contrasting patterns of trematode flow in a fishpond area in Central Europe

Czech Academy of Sciences Publication Activity Database

Soldánová, Miroslava; Faltýnková, Anna; Scholz, Tomáš; Kostadinova, Aneta

2011-01-01

Roč. 138, č. 6 (2011), 789-807 ISSN 0031-1820 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lymnaea stagnalis * trematode community structure * spatial variation * parasite flow * eutrophic fishponds Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.961, year: 2011

Cistitis por schistosoma haematobium, presentación de un caso

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Ramón Zaragoza Durañona

2014-08-01

Full Text Available No es frecuente en nuestro medio la infección por Schistosoma. haematobium, pero existen todos los elementos de la triada ecológica para su transmisión. Se presenta el caso de un paciente masculino, de raza mestiza, con 46 años de edad y procedencia rural, que refiere dolores lumbares al orinar, disuria, tenesmo vesical y polaquiuria durante el último año. Al examen físico se encontró el abdomen discretamente doloroso a la palpación superficial y profunda en hipogastrio y fosas lumbares. Se trató como una infección urinaria sin mejoría. Los complementarios arrojaron discreta eosinofilia y reflujo vesicoureteral grado IV en la uretrocistografía retrógrada y miccional. La cistoscopia videoasistida reportó, a nivel del trígono, la mucosa vesical enrojecida con estructuras en forma de granos de arroz de aspecto puntiforme; la biopsia informó huevos de esquistosomas y cambios metaplásicos en el epitelio vesical. Se trató con praziquantel y desaparecieron los síntomas. A los seis meses los complementarios resultaron normales y el paciente está asintomático. Se concluye en la importancia de considerar la infección por Schistosoma haematobium entre los diagnósticos de la infección urinaria refractaria al tratamiento

The feasibility of MS and advanced data processing for monitoring Schistosoma mansoni infection

DEFF Research Database (Denmark)

Balog, Crina I.A.; Alexandrov, Theodore; Derks, Rico J.

2010-01-01

Sensitive diagnosis, monitoring of disease progression and the evaluation of chemotherapeutic interventions are of prime importance for the improvement of control and prevention strategies for Schistosomiasis. The aim of the present study was to identify novel markers of Schistosoma mansoni...

Experimental infection with the small intestinal trematode, Haplorchis pumilio, in young dogs

DEFF Research Database (Denmark)

Nissen, Sofie; Nguyen, Lan Anh Thi; Dalsgaard, Anders

2013-01-01

included as uninfected controls. Faecal examination for eggs was performed twice weekly using a sieving and sedimentation technique. Body temperature and weight of the dogs were measured as was total white blood cells, blood eosinophils and packed cell volume. Subsets of dogs were examined post......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on the role of domestic animals in the transmission of FZT in Northern Vietnam found that dogs, mainly infected with Haplorchis pumilio, contributed widely to the transmission of FZT. On this background, we...... conducted an experimental infection with H. pumilio to elucidate population dynamics and host reactions in dogs. Eight household-reared dogs (3-6 months old), were each orally infected with 500 H. pumilio metacercariae obtained by artificial digestion of naturally infected fish. Another eight dogs were...

Molecular identification of Clonorchis sinensis and discrimination with other opisthorchid liver fluke species using Multiple Ligation-dependent Probe Amplification (MLPA).

OpenAIRE

Sun, J.; Xu, J.; Liang, P.; Mao, Q.; Huang, Y.; Lu, X.; Deng, C.; Liang, C.; de Hoog, G.S.; Yu, X.

2011-01-01

Background Infections with the opisthorchid liver flukes Clonorchis sinensis, Opisthorchis viverrini, and O. felineus cause severe health problems globally, particularly in Southeast Asia. Early identification of the infection is essential to provide timely and appropriate chemotherapy to patients. Results In this study we evaluate a PCR-based molecular identification method, Multiplex Ligation-dependent Probe Amplification (MLPA), which allows rapid and specific detection of single nucleotid...

Molecular Characterization of Fasciola Samples Using Sequences of Second Internal Transcribed Spacer-rDNA in Different Geographical Localities of Sistan and Balouchestan Province, Iran

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Mahsa Shahbakhsh

2016-02-01

Full Text Available Background: The Fasciola trematodes are the most common liver flukes, living in a range of animals with global distribution and resulting in profound economic loss and public health challenges. Previous studies have indicated that the sequences of the second internal transcribed spacer (ITS-2 of ribosomal DNA (rDNA provide reliable genetic markers for molecular systemic studies of Fasciola. Objectives: The objective of the present study was to characterize Fasciola samples from different geographical regions of Sistan and Balouchestan province using sequences of second internal transcribed spacer (ITS-2 of ribosomal DNA (rDNA. Materials and Methods: Twenty adult trematodes were collected from the livers of slaughtered infected cattle. Total genomic DNA was extracted and ITS-2 rDNA targets were amplified by polymerase chain reaction (PCR. All samples were sequenced and investigated using the ClustalW2 sequence alignment tool and MEGA software. The sequences of some Iranian and non-Iranian isolates were used for comparison, in order to evaluate the variation in sequence homology between geographically different trematode populations. Results: The results of comparing the ITS-2 sequences with the BLAST GenBank database showed one type of sequence for F. hepatica and three different types of sequences for F. gigantica in the specimens. Conclusions: The present study demonstrated that Fasciola samples from cattle in two geographical locations in Sistan and Balouchestan province represented no genetic diversity in F. hepatica and high genetic variation in F. gigantica.

Import of exotic and zoonotic trematodes (Heterophyidae: Centrocestus sp.) in Xiphophorus maculatus

DEFF Research Database (Denmark)

Mehrdana, Foojan; Jensen, Hannah M.; Kania, Per Walter

2014-01-01

metacercaria with an X-shaped excretory bladder. PCR amplification of a rDNA region (5.8S rRNA gene, ITS-2, 28S rRNA gene) and subsequent sequencing confirmed the diagnosis. Metacercariae were found in gill filaments adjacent to the cartilage associated with cartilage hypertrophy, epithelial and mucous cell...... hyperplasia, clubbing and lamellar fusion. Host cell encapsulation of cysts comprised several layers of leucocytes, chondroblast-like and fibroblast like cells. The observations raise concerns with regard to veterinary inspection and quarantine procedures. The zoonotic potential of these trematodes...

Genome-wide characterization of microsatelittes and marker development in the carcinogenic liver fluke Clonorchis sinensis

Science.gov (United States)

Nguyen, Thao T.B.; Arimatsu, Yuji; Hong, Sung-Jong; Brindley, Paul J.; Blair, David; Laha, Thewarach; Sripa, Banchob

2015-01-01

Clonorchis sinensis is an important carcinogenic human liver fluke endemic in East and Southeast Asia. There are several conventional molecular markers have been used for identification and genetic diversity, however, no information about microsatellites of this liver fluke published so far. We here report microsatellite characterization and marker development for genetic diversity study in C. sinensis using genome-wide bioinformatics approach. Based on our search criteria, a total of 256,990 microsatellites (≥ 12 base pairs) were identified from genome database of C. sinensis with hexa-nucleotide motif being the most abundant (51%) followed by penta-nucleotide (18.3%) and tri-nucleotide (12.7%). The tetra-nucleotide, di-nucleotide and mononucleotide motifs accounted for 9.75 %, 7.63% and 0.14%, respectively. The total length of all microsatellites accounts for 0. 72 % of 547 Mb of the whole genome size and the frequency of microsatellites were found to be one microsatellite in every 2.13 kb of DNA. For the di-, tri, and tetra-nucleotide, the repeat numbers redundant are six (28%), four (45%) and three (76%), respectively. The ATC repeat is the most abundant microsatellites followed by AT, AAT and AC, respectively. Within 40 microsatellite loci developed, 24 microsatellite markers showed potential to differentiate between C. sinensis and O. viverrini. Seven out of 24 loci showed heterozygous with observed heterozygosity ranged from 0.467 to 1. Four-primer sets could amplify both C. sinensis and O. viverrini DNA with different sizes. This study provides basic information of C. sinensis microsatellites and the genome-wide markers developed may be a useful tool for genetic study of C. sinensis. PMID:25782682

Genome-wide characterization of microsatellites and marker development in the carcinogenic liver fluke Clonorchis sinensis.

Science.gov (United States)

Nguyen, Thao T B; Arimatsu, Yuji; Hong, Sung-Jong; Brindley, Paul J; Blair, David; Laha, Thewarach; Sripa, Banchob

2015-06-01

Clonorchis sinensis is an important carcinogenic human liver fluke endemic in East and Southeast Asia. There are several conventional molecular markers that have been used for identification and genetic diversity; however, no information about microsatellites of this liver fluke is published so far. We here report microsatellite characterization and marker development for a genetic diversity study in C. sinensis, using a genome-wide bioinformatics approach. Based on our search criteria, a total of 256,990 microsatellites (≥12 base pairs) were identified from a genome database of C. sinensis, with hexanucleotide motif being the most abundant (51%) followed by pentanucleotide (18.3%) and trinucleotide (12.7%). The tetranucleotide, dinucleotide, and mononucleotide motifs accounted for 9.75, 7.63, and 0.14%, respectively. The total length of all microsatellites accounts for 0. 72% of 547 Mb of the whole genome size, and the frequency of microsatellites was found to be one microsatellite in every 2.13 kb of DNA. For the di-, tri-, and tetranucleotide, the repeat numbers redundant are six (28%), four (45%), and three (76%), respectively. The ATC repeat is the most abundant microsatellites followed by AT, AAT, and AC, respectively. Within 40 microsatellite loci developed, 24 microsatellite markers showed potential to differentiate between C. sinensis and Opisthorchis viverrini. Seven out of 24 loci showed to be heterozygous with observed heterozygosity that ranged from 0.467 to 1. Four primer sets could amplify both C. sinensis and O. viverrini DNA with different sizes. This study provides basic information of C. sinensis microsatellites, and the genome-wide markers developed may be a useful tool for the genetic study of C. sinensis.

A new PCR-based approach indicates the range of Clonorchis sinensis now extends to Central Thailand.

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Rebecca J Traub

Full Text Available Differentiation of the fish-borne trematodes belonging to the Opisthorchiidae, Heterophyidae and Lecithodendriidae is important from a clinical and epidemiological perspective, yet it is impossible to do using conventional coprological techniques, as the eggs are morphologically similar. Epidemiological investigation therefore currently relies on morphological examination of adult worms following expulsion chemotherapy. A PCR test capable of amplifying a segment of the internal transcribed spacer region of ribosomal DNA for the opisthorchiid and heterophyid flukes eggs taken directly from faeces was developed and evaluated in a rural community in central Thailand. The lowest quantity of DNA that could be amplified from individual adults of Opisthorchis viverrini, Clonorchis sinensis and Haplorchis taichui was estimated at 0.6 pg, 0.8 pg and 3 pg, respectively. The PCR was capable of detecting mixed infection with the aforementioned species of flukes under experimental conditions. A total of 11.6% of individuals in rural communities in Sanamchaikaet district, central Thailand, were positive for 'Opisthorchis-like' eggs in their faeces using conventional parasitological detection techniques. In comparison to microscopy, the PCR yielded a sensitivity and specificity of 71.0% and 76.7%, respectively. Analysis of the microscopy-positive PCR products revealed 64% and 23% of individuals to be infected with O. viverrini and C. sinensis, respectively. The remaining 13% (three individuals were identified as eggs of Didymozoidae, presumably being passed mechanically in the faeces following the ingestion of infected fishes. An immediate finding of this study is the identification and first report of a C. sinensis-endemic community in central Thailand. This extends the known range of this liver fluke in Southeast Asia. The PCR developed herein provides an important tool for the specific identification of liver and intestinal fluke species for future

Schistosoma mansoni infection along the coast of Lake Victoria in Mwanza region, Tanzania

DEFF Research Database (Denmark)

Olsen, Annette; Kinung'hi, Safari; Magnussen, Pascal

2015-01-01

Prevalence and intensity of Schistosoma mansoni infection according to age, sex, and occupation were investigated in 100 first-year students (aged 7-8 years), 100 schoolchildren (aged 9-12 years), and 50 adults (aged 20-55 years) from 149 villages. The schoolchildren provided three stool specimen...

Increased prevalence of leukocytes and elevated cytokine levels in semen from Schistosoma haematobium-infected individuals

DEFF Research Database (Denmark)

Leutscher, Peter D C; Pedersen, Mette; Raharisolo, Clairette

2005-01-01

In this study, we investigated the seminal inflammatory response to egg infestation of the urogenital organs in 240 semen-donating men aged 15-49 years living in a Schistosoma haematobium-endemic area of Madagascar. In 29 subjects (12%) with excretion of > or =5 ova/ejaculate, leukocytospermia (>10...

High burden of Schistosoma mansoni infection in school-aged children in Marolambo District, Madagascar.

Science.gov (United States)

Spencer, Stephen A; Penney, James M St John; Russell, Hannah J; Howe, Anthony P; Linder, Cortland; Rakotomampianina, Andriamahitsisambatra L D; Nandimbiniaina, Anjara M; Squire, S Bertel; Stothard, J Russell; Bustinduy, Amaya L; Rahetilahy, Alain M

2017-06-24

A school-based survey was undertaken to assess prevalence and infection intensity of schistosomiasis in school-aged children in the Marolambo District of Madagascar. School-aged children from six purposively selected schools were tested for Schistosoma haematobium by urine filtration and Schistosoma mansoni using circulating cathodic antigen (CCA) and Kato-Katz stool analysis. The investigators did not address soil-transmitted helminths (STH) in this study. Of 399 school-aged children screened, 93.7% were infected with S. mansoni based on CCA analysis. Kato-Katz analysis of stool revealed S. mansoni infection in 73.6% (215/ 292). Heavy infections (> 400 eggs per gram) were common (32.1%; 69/ 215), with a mean of 482 eggs per gram of stool. Moderate infection intensities were detected in 31.2% (67/ 215) and light infection intensities in 36.7% (79/ 215) of infected participants. No infection with S. haematobium was detected by urine filtration. Intestinal schistosomiasis appears a considerable public health issue in this remote area of Madagascar where there is a pressing need for mass drug administration.

Schistosoma mansoni infection in a fishermen community, the Lake Manzala region-Egypt

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Amira Taman

2014-12-01

Full Text Available Objective: To determine the prevalence of schistosomiasis in the fishermen community in Egypt. Methods: A cross-sectional survey for schistosomiasis mansoni was conducted among 150 fishermen and their families from January to November 2013. Faecal samples were examined by Kato Katz method and formalin-ether concentration technique. Malacological survey was conducted to identify infection of the snail intermediate host by larval stage of Schistosoma mansoni. Snails were collected and checked for shedding of cercariae after light exposure. Results: Overall prevalence of infection was 26.6% with an intensity of (42.7依7.2 ova/g of stool. Infection was common in male and significantly increased in the age of 20-40 years. Praziquanteltreated individuals had a high significant decrease in intensity (27.2依2.4 ova/g of stool than those with no treatment history. Biomphalaria alexandrina snail was infected with Schistosoma mansoni particularly in warm seasons and mice infection was established successfully from the shed cercariae, moreover adult worms were obtained via portal perfusion of the infected mice. Conclusions: Findings indicated the endemicity of schistosomiasis mansoni in Lake Manzala region, therefore, appropriate integrated control measures are needed among fishermen including health education, environmental sanitation, periodic screening and mass treatment with praziquantel.

Fast evolutionary rates associated with functional loss in class I glucose transporters of Schistosoma mansoni

Czech Academy of Sciences Publication Activity Database

Cabezas-Cruz, A.; Valdés, James J.; Lancelot, J.; Pierce, R.J.

2015-01-01

Roč. 16, NOV 19 2015 (2015), s. 980 ISSN 1471-2164 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Schistosoma mansoni * glucose transporters * transcriptional regulation * phylogen * biophysics Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.867, year: 2015

Schistosoma mansoni and HIV infection in a Ugandan population with high HIV and helminth prevalence.

Science.gov (United States)

Sanya, Richard E; Muhangi, Lawrence; Nampijja, Margaret; Nannozi, Victoria; Nakawungu, Prossy Kabuubi; Abayo, Elson; Webb, Emily L; Elliott, Alison M

2015-09-01

Recent reports suggest that Schistosoma infection may increase the risk of acquiring human immunodeficiency virus (HIV). We used data from a large cross-sectional study to investigate whether Schistosoma mansoni infection is associated with increased HIV prevalence. We conducted a household survey of residents in island fishing communities in Mukono district, Uganda, between October 2012 and July 2013. HIV status was assessed using rapid test kits. Kato-Katz (KK) stool tests and urine-circulating cathodic antigen (CCA) were used to test for Schistosoma infection. Multivariable logistic regression, allowing for the survey design, was used to investigate the association between S. mansoni infection and HIV infection. Data from 1412 participants aged 13 years and older were analysed (mean age 30.3 years, 45% female). The prevalence of HIV was 17.3%. Using the stool Kato-Katz technique on a single sample, S. mansoni infection was detected in 57.2% (719/1257) of participants; urine CCA was positive in 73.8% (478/650) of those tested. S. mansoni infection was not associated with HIV infection. [KK (aOR = 1.04; 95% CI: 0.74-1.47, P = 0.81), CCA (aOR = 1.53; 95% CI: 0.78-3.00, P = 0.19)]. The median S. mansoni egg count per gram was lower in the HIV-positive participants (P = 0.005). These results add to the evidence that S. mansoni has little effect on HIV transmission, but may influence egg excretion. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Immunolocalization of Schistosoma mansoni and Schistosoma haematobium antigens reacting with their Egyptian snail vectors.

Science.gov (United States)

El-Dafrawy, Shadia M; Mohamed, Amira H; Hammam, Olfat A; Rabia, Ibrahim

2007-12-01

The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails.

Projecting the long-term impact of school- or community-based mass-treatment interventions for control of Schistosoma infection.

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Xiaoxia Wang

Full Text Available Schistosomiasis remains a significant health burden in many areas of the world. Morbidity control, focused on limiting infection intensity through periodic delivery of anti-schistosomal medicines, is the thrust of current World Health Organization guidelines (2006 for reduction of Schistosoma-related disease. A new appreciation of the lifetime impact of repeated Schistosoma infection has directed attention toward strategies for greater suppression of parasite infection per se, with the goal of transmission interruption. Variations in drug schedules involving increased population coverage and/or treatment frequency are now undergoing field trials. However, their relative effectiveness in long-term infection suppression is presently unknown.Our study used available field data to calibrate advanced network models of village-level Schistosoma transmission to project outcomes of six different community- or school age-based programs, as compared to the impact of current 2006 W.H.O. recommended control strategies. We then scored the number of years each of 10 typical villages would remain below 10% infection prevalence (a practicable level associated with minimal prevalence of disease. All strategies that included four annual treatments effectively reduced community prevalence to less than 10%, while programs having yearly gaps ('holidays' failed to reach this objective in half of the communities. Effective post-program suppression of infection prevalence persisted in half of the 10 villages for 7-10 years, whereas in five high-risk villages, program effects on prevalence lasted zero to four years only.At typical levels of treatment adherence (60 to 70%, current WHO recommendations will likely not achieve effective suppression of Schistosoma prevalence unless implemented for ≥6 years. Following more aggressive 4 year annual intervention, some communities may be able to continue without further intervention for 8-10 years, while in higher

Structural bioinformatics study of PNP from Schistosoma mansoni

International Nuclear Information System (INIS)

Silveira, Nelson Jose Freitas da; Uchoa, Hugo Brandao; Canduri, Fernanda; Pereira, Jose Henrique; Camera, Joao Carlos; Basso, Luiz Augusto; Palma, Mario Sergio; Santos, Diogenes Santiago; Filgueira de Azevedo, Walter

2004-01-01

The parasite Schistosoma mansoni lacks the de novo pathway for purine biosynthesis and depends on salvage pathways for its purine requirements. Schistosomiasis is endemic in 76 countries and territories and amongst the parasitic diseases ranks second after malaria in terms of social and economic impact and public health importance. The PNP is an attractive target for drug design and it has been submitted to extensive structure-based design. The atomic coordinates of the complex of human PNP with inosine were used as template for starting the modeling of PNP from S. mansoni complexed with inosine. Here we describe the model for the complex SmPNP-inosine and correlate the structure with differences in the affinity for inosine presented by human and S. mansoni PNPs

Biolistic transformation of Schistosoma mansoni: Studies with modified reporter-gene constructs containing regulatory regions of protease genes

Czech Academy of Sciences Publication Activity Database

Dvořák, Jan; Beckmann, S.; Lim, K.-C.; Engel, J. C.; Grevelding, C. G.; McKerrow, J. H.; Caffrey, C. R.

2010-01-01

Roč. 170, č. 1 (2010), s. 37-40 ISSN 0166-6851 Institutional research plan: CEZ:AV0Z60220518 Keywords : Schistosoma * Protease * Transgene * Gene promoter * Biolistics * Electroporation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.875, year: 2010

About some trematodes parasites of Haemulon sciurus (Shaw, 1803

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A. Kohn

1982-06-01

Full Text Available From September, 1980 to August, 1981 forty specimens of Haemulon sciurus from "Praia da Ribeira, Ilha do Governador", Rio de Janeiro State, were examined for parasites. In this paper, parcial results concerning only the collected trematodes are reported: Diplomonorchis leiostomi Hopkins, 1941 (first record in Brazil and in a new host; Lasiotocus beauforti (Hopkins, 1941 Thomas, 1959 (new host record; Genolopa ampullacea Linton, 1910; Parahemiurus merus (Linton, 1910 Yamaguti, 1938 (new host record: Aponurus pyriformis (Linton, 1910 Overstreet, 1973 and Diplangus paxillus Linton, 1910. Figures, measurements and comments of each species are given.De setembro, 1980 a agosto, 1981 foram examinados 40 exemplares de Haemulon sciurus, provenientes da Praia da Ribeira, Ilha do Governador, Estado do Rio de Janeiro. Neste trabalho são apresentados os resultados parciais, correspondentes aos trematodeos, grupo que apresentou maior ocorrência de parasitismo. As especies estudadas foram: Diplomonorchis leiostomi Hopkins, 1941 (primeira ocorrencia no Brasil e em novo hospedeiro; Lasiotocus beauforti (Hopkins, 1941 Thomas, 1959 (em novo hospedeiro; Genolopa ampullacea Linton, 1910; Parahemiurus merus (Linton, 1910 Yamaguti, 1938 (em um novo hospedeiro; Aponurus pyriformis (Linton, 1910 Overstreet, 1973 e Diplangus paxillus Linton, 1910. São apresentadas figuras, medidas e comentários.

New data in France on the trematode Alaria alata (Goeze, 1792) obtained during Trichinella inspections

Science.gov (United States)

Portier, J.; Jouet, D.; Ferté, H.; Gibout, O.; Heckmann, A.; Boireau, P.; Vallée, I.

2011-01-01

The trematode Alaria alata is a cosmopolite parasite found in red foxes (Vulpes vulpes), the main definitive host in Europe. In contrast only few data are reported in wild boars (Sus scrofa), a paratenic host. The aim of this paper is to describe the importance and distribution of Alaria alata mesocercariae in wild boars, information is given by findings of these larvae during Trichinella mandatory meat inspection on wild boars’ carcasses aimed for human consumption. More than a hundred cases of mesocercariae positive animals are found every year in the East of France. First investigations on the parasite’s resistance to deep-freezing in meat are presented in this work. PMID:21894269

Frequency and mitotic heritability of epimutations in Schistosoma mansoni.

Science.gov (United States)

Roquis, David; Rognon, Anne; Chaparro, Cristian; Boissier, Jerome; Arancibia, Nathalie; Cosseau, Celine; Parrinello, Hugues; Grunau, Christoph

2016-04-01

Schistosoma mansoni is a parasitic platyhelminth responsible for intestinal bilharzia. It has a complex life cycle, infecting a freshwater snail of the Biomphalaria genus, and then a mammalian host. Schistosoma mansoni adapts rapidly to new (allopatric) strains of its intermediate host. To study the importance of epimutations in this process, we infected sympatric and allopatric mollusc strains with parasite clones. ChIP-Seq was carried out on four histone modifications (H3K4me3, H3K27me3, H3K27ac and H4K20me1) in parallel with genomewide DNA resequencing (i) on parasite larvae shed by the infected snails and (ii) on adult worms that had developed from the larvae. No change in single nucleotide polymorphisms and no mobilization of transposable elements were observed, but 58-105 copy number variations (CNVs) within the parasite clones in different molluscs were detected. We also observed that the allopatric environment induces three types of chromatin structure changes: (i) host-induced changes on larvae epigenomes in 51 regions of the genome that are independent of the parasites' genetic background, (ii) spontaneous changes (not related to experimental condition or genotype of the parasite) at 64 locations and (iii) 64 chromatin structure differences dependent on the parasite genotype. Up to 45% of the spontaneous, but none of the host-induced chromatin structure changes were transmitted to adults. In our model, the environment induces epigenetic changes at specific loci but only spontaneous epimutations are mitotically heritable and have therefore the potential to contribute to transgenerational inheritance. We also show that CNVs are the only source of genetic variation and occur at the same order of magnitude as epimutations. © 2016 John Wiley & Sons Ltd.

Consistent pattern of local adaptation during an experimental heat wave in a pipefish-trematode host-parasite system.

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Susanne H Landis

Full Text Available Extreme climate events such as heat waves are expected to increase in frequency under global change. As one indirect effect, they can alter magnitude and direction of species interactions, for example those between hosts and parasites. We simulated a summer heat wave to investigate how a changing environment affects the interaction between the broad-nosed pipefish (Syngnathus typhle as a host and its digenean trematode parasite (Cryptocotyle lingua. In a fully reciprocal laboratory infection experiment, pipefish from three different coastal locations were exposed to sympatric and allopatric trematode cercariae. In order to examine whether an extreme climatic event disrupts patterns of locally adapted host-parasite combinations we measured the parasite's transmission success as well as the host's adaptive and innate immune defence under control and heat wave conditions. Independent of temperature, sympatric cercariae were always more successful than allopatric ones, indicating that parasites are locally adapted to their hosts. Hosts suffered from heat stress as suggested by fewer cells of the adaptive immune system (lymphocytes compared to the same groups that were kept at 18°C. However, the proportion of the innate immune cells (monocytes was higher in the 18°C water. Contrary to our expectations, no interaction between host immune defence, parasite infectivity and temperature stress were found, nor did the pattern of local adaptation change due to increased water temperature. Thus, in this host-parasite interaction, the sympatric parasite keeps ahead of the coevolutionary dynamics across sites, even under increasing temperatures as expected under marine global warming.

Cyclophilin A enhances cell proliferation and tumor growth of liver fluke-associated cholangiocarcinoma

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Sawanyawisuth Kanlayanee

2011-08-01

Full Text Available Abstract Background Cyclophilin A (CypA expression is associated with malignant phenotypes in many cancers. However, the role and mechanisms of CypA in liver fluke-associated cholangiocarcinoma (CCA are not presently known. In this study, we investigated the expression of CypA in CCA tumor tissues and CCA cell lines as well as regulation mechanisms of CypA in tumor growth using CCA cell lines. Methods CypA expression was determined by real time RT-PCR, Western blot or immunohistochemistry. CypA silence or overexpression in CCA cells was achieved using gene delivery techniques. Cell proliferation was assessed using MTS assay or Ki-67 staining. The effect of silencing CypA on CCA tumor growth was determined in nude mice. The effect of CypA knockdown on ERK1/2 activation was assessed by Western blot. Results CypA was upregulated in 68% of CCA tumor tissues. Silencing CypA significantly suppressed cell proliferation in several CCA cell lines. Likewise, inhibition of CypA peptidyl-prolyl cis-trans isomerase (PPIase activity using cyclosporin A (CsA decreased cell proliferation. In contrast, overexpression of CypA resulted in 30% to 35% increases in proliferation of CCA cell lines. Interestingly, neither silence nor overexpression of CypA affected cell proliferation of a non-tumor human cholangiocyte cell line, MMNK1. Suppression of CypA expression attenuated ERK1/2 activity in CCA M139 cells by using both transient and stable knockdown methods. In the in vivo study, there was a 43% reduction in weight of tumors derived from CypA-silenced CCA cell lines compared with control vector CCA tumors in mice; these tumors with stable CypA silencing showed a reduced cell proliferation. Conclusions CypA is upregulated in majority of CCA patients' tissues and confers a significant growth advantage in CCA cells. Suppression of CypA expression decreases proliferation of CCA cell lines in vitro and reduces tumor growth in the nude mouse model. Inhibition of Cyp

Changes in the expression of Hepatic Cytochrome P450 Isoenzymes 2E1, 2B1/2, 4A, and 2C6 in mice infected with different levels of Schistosoma Mansoni Cercariae

International Nuclear Information System (INIS)

Sheweita, Salah A.

2005-01-01

Most xenobiotic agents are metabolized by cytochrome P450 system. In the present study, Western blotting was used to investigate the effect of different levels of Schistosoma Mansoni infection on the expression of somr cytochrome P450 isozymes (CYP 2E1, 2B1/2, 2C6, 4A) and to enzyme assay their related metabolic functions in mouse liver microsomes. Male mice were infected with 60, 120, 180, 300 and 600 Schistosoma Mansoni cercariae per mouse for 33 days and 60, 120, 180 and 300 cercariae/mouse with no change at the last level of Schistosoma Mansoni infection. Also the expression of CYP 4A was potentially induced at all levels of Schistosoma Mansoni infection. A significant induction of CYP 2B1/2 expression was observed at all levels of Schistosoma Mansoni infection with loss of signal at 180 cercariaea/mouse. In contrast, CYP 2C6 expression was induced at the first two levels and such expression was decreased at the last three levels. In addition, the infection of the mouse with 60, 120 and 180 cercariae/mouse decreased; [1] 7-methoxycoumarin O-demethylase activity by 36, 54 and 58% respectively; [2] 7-ethoxycoumarin O-deethylase activity by 33, 40 and 57% respectively; [3] coumarin hydroxlase activity by 33, 45 and 55% respectively. However, 300 and 600 cercariae/mouse induced: [1] 7-methoxycoumarin O-demethylase activity by 45 and 97% respectively: [2] 7-ethoxycoumarin O-deethylase activity by 26 and 90% respectively; [3] coumarin hydroxylase activity by 100 and 200% respectively. In addition, all levels of Schistosoma Mansoni infection decreased the sleeping time caused by hexobarital. It is concluded that different levels of Schistosoma Mansoni infection change the expression of different CYPisozymes and that these alterations could enhance the carcinogenicity of N-nitrosamines which is mainly dependent on CYP 2E1. The alterations in the expression of CYP 2E1, 4A and 2B1/2 isozymes as a result of Schistosoma Mansoni infection may change the therapeutic actions

Fine-scale mapping of vector habitats using very high resolution satellite imagery: a liver fluke case-study.

Science.gov (United States)

De Roeck, Els; Van Coillie, Frieke; De Wulf, Robert; Soenen, Karen; Charlier, Johannes; Vercruysse, Jozef; Hantson, Wouter; Ducheyne, Els; Hendrickx, Guy

2014-12-01

The visualization of vector occurrence in space and time is an important aspect of studying vector-borne diseases. Detailed maps of possible vector habitats provide valuable information for the prediction of infection risk zones but are currently lacking for most parts of the world. Nonetheless, monitoring vector habitats from the finest scales up to farm level is of key importance to refine currently existing broad-scale infection risk models. Using Fasciola hepatica, a parasite liver fluke, as a case in point, this study illustrates the potential of very high resolution (VHR) optical satellite imagery to efficiently and semi-automatically detect detailed vector habitats. A WorldView2 satellite image capable of transmitted by freshwater snails. The vector thrives in small water bodies (SWBs), such as ponds, ditches and other humid areas consisting of open water, aquatic vegetation and/or inundated grass. These water bodies can be as small as a few m2 and are most often not present on existing land cover maps because of their small size. We present a classification procedure based on object-based image analysis (OBIA) that proved valuable to detect SWBs at a fine scale in an operational and semi-automated way. The classification results were compared to field and other reference data such as existing broad-scale maps and expert knowledge. Overall, the SWB detection accuracy reached up to 87%. The resulting fine-scale SWB map can be used as input for spatial distribution modelling of the liver fluke snail vector to enable development of improved infection risk mapping and management advice adapted to specific, local farm situations.

Distribution and habitats of Lymnaea natalensis, snail intermediate host of the liver fluke Fasciola gigantica, in South Africa

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Editorial Office

2001-09-01

Full Text Available This paper focuses on the geographical distribution and the habitats of Lymnaea natalensis, the snail intermediate host of the liver fluke, Fasciola gigantica, as reflected by the collection sites of its 4 552 samples currently on record in the National Freshwater Snail Collection (NFSC of South Africa. Although this species was represented in a variety of waterbodies, the majority of samples(±70%came from rivers, brooks and dams and in 70.8% of the cases the water was described as permanent and in 71.8% as slow flowing or standing. The results of life-table studies conducted by various authors indicated that temperature should be a relatively unimportant factor in determining its geographical distribution, but that the availability of permanent water should be decisive for its presence in a given habitat. These results are in agreement with the finding that only 7.5% of the samples of this species in the NFSC were collected in habitats which were described as seasonal. Furthermore, it gives a logical explanation for the sporadic occurrence, or total absence of this species in the more arid regions of South Africa. Water impoundments and irrigation networks contribute to a large extent towards creating perennial habitats which would be suitable for L. natalensis. As intermediate host for one of the liver fluke species which already is an economic factor in South Africa, this certainly is an aspect which ought to be reckoned within the planning and construction of new irrigation schemes.

The Role of Spatial and Temporal Heterogeneity and Competition In Structuring Trematode Communities In the Great Pond Snail, Lymnaea stagnalis (L.)

Czech Academy of Sciences Publication Activity Database

Soldánová, Miroslava; Kuris, A. M.; Scholz, Tomáš; Lafferty, K. D.

2012-01-01

Roč. 98, č. 3 (2012), s. 460-471 ISSN 0022-3395 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : LARVAL TREMATODES * HELISOMA-ANCEPS * INTERSPECIFIC INTERACTIONS * DIPLOSTOMUM-SPATHACEUM * CENTRAL-EUROPE * ANTAGONISM * PARASITES * HOST * PATTERNS * DYNAMICS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.321, year: 2012

A comparative study of karyotypes and chromosomal location of rDNA genes in important liver flukes Fasciola hepatica and Fascioloides magna (Trematoda: Fasciolidae)

Czech Academy of Sciences Publication Activity Database

Reblánová, M.; Špakulová, M.; Orosová, Martina; Kraľová-Hromadová, I.; Bazsalovicsová, E.; Rajský, D.

2011-01-01

Roč. 109, č. 4 (2011), s. 2021-1028 ISSN 0932-0113 Institutional research plan: CEZ:AV0Z60220518 Keywords : SCHISTOSOMA-MANSONI * DIFFERENTIATION * FISH * ITS2 * HYBRIDIZATION * EPIDEMIOLOGY * LOCALIZATION * CYTOGENETICS * SHEEP Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.149, year: 2011

Lineage-specific expansion and loss of tyrosinase genes across platyhelminths and their induction profiles in the carcinogenic oriental liver fluke, Clonorchis sinensis.

Science.gov (United States)

Kim, Seon-Hee; Bae, Young-An

2017-09-01

Tyrosinase provides an essential activity during egg production in diverse platyhelminths by mediating sclerotization of eggshells. In this study, we investigated the genomic and evolutionary features of tyrosinases in parasitic platyhelminths whose genomic information is available. A pair of paralogous tyrosinases was detected in most trematodes, whereas they were lost in cyclophyllidean cestodes. A pseudophyllidean cestode displaying egg biology similar to that of trematodes possessed an orthologous gene. Interestingly, one of the paralogous tyrosinases appeared to have been multiplied into three copies in Clonorchis sinensis and Opisthorchis viverrini. In addition, a fifth tyrosinase gene that was minimally transcribed through all developmental stages was further detected in these opisthorchiid genomes. Phylogenetic analyses demonstrated that the tyrosinase gene has undergone duplication at least three times in platyhelminths. The additional opisthorchiid gene arose from the first duplication. A paralogous copy generated from these gene duplications, except for the last one, seemed to be lost in the major neodermatans lineages. In C. sinensis, tyrosinase gene expressions were initiated following sexual maturation and the levels were significantly enhanced by the presence of O2 and bile. Taken together, our data suggest that tyrosinase has evolved lineage-specifically across platyhelminths related to its copy number and induction mechanism.

Defense response of susceptible and resistant Biomphalaria alexandrina snails against Schistosoma mansoni infection

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Iman F. Abou-El-Naga

2012-09-01

Full Text Available In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. The fates of Schistosoma miracidia in the snails varies between different species of Biomphalaria. The internal defense system is one of the factors that influence the susceptibility pattern of the snails. The interaction between Biomphalaria snails and S. mansoni needs to be identified for each species, and even between the members of the same species with different degrees of susceptibility. In the present study, the first generation of susceptible and resistant parents of B. alexandrina was examined histologically at the 30th day post exposure. The study includes the characterization of the immune response, as expressed by tissue reactions, of susceptible and resistant B. alexandrina snails against S. mansoni. It was also designed to determine the impact of the resistance increase in parent snails, on the mechanisms of interaction of their offspring against infection. The results showed that the infection rate of the offspring from the susceptible parents was 92%. No susceptible offspring was produced from the resistant parents. When the parents were of equal number of susceptible and resistant snails, they gave an offspring with an infection rate of 20%. Susceptible snails that had susceptible parents showed a higher degree of susceptibility than those that had both susceptible and resistant parents. A common feature of the resistant snails was the absence of any viable parasites. The tissue reactions of the resistant snails having only resistant parents occurred at the site of miracidial penetration. In resistant snails for which susceptible ones were included in their parents, the reactions occurred in the deep tissues. These results characterized the immune response of B. alexandrina snails against Schistosoma infection which was found to occur by two different mechanisms. One type of defense occurs in highly resistant snails, and employs direct

Liver Fluke Infection and Fish Consumption in Khon Kaen, Thailand: A Case Study on Negotiating the Middle Ground between Western Science and Eastern Culture

Science.gov (United States)

Samiphak, Sara

This research investigates why typical strategies for promoting health, prolonging life, and preventing disease do not work in many communities. I use the liver fluke infection endemic in Khon Kaen, Thailand to explore the middle ground between Western science and Eastern culture. Prior work on the O.viverrini infection in Khon Kaen, Thailand has focused almost exclusively on developing effective medical treatment for the liver fluke infection. This dissertation employs a case study designed to explore the conditions that created and perpetuate the problem in the first place. In concrete terms, I analyze how the worldviews of local villagers shape their attitudes toward life (and death), which in turn determine if they engage in the high-risk behavior -- eating undercooked fish -- that makes them vulnerable to the infection. My research focuses on these people in-situ over a three-month period, and includes data from participant-observation, interviews, and video-recordings. This work seeks to illuminate how people's thinking and reasoning skills, and personal/cultural identities affect their abilities to learn and act on new health concepts. This potentially provides a window into future educational strategies in a complex world.

Granulocytes in Helminth Infection - Who is Calling the Shots?

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Makepeace, BL; Martin, C; Turner, JD; Specht, S

2012-01-01

Helminths are parasitic organisms that can be broadly described as “worms” due to their elongated body plan, but which otherwise differ in shape, development, migratory routes and the predilection site of the adults and larvae. They are divided into three major groups: trematodes (flukes), which are leaf-shaped, hermaphroditic (except for blood flukes) flatworms with oral and ventral suckers; cestodes (tapeworms), which are segmented, hermaphroditic flatworms that inhabit the intestinal lumen; and nematodes (roundworms), which are dioecious, cylindrical parasites that inhabit intestinal and peripheral tissue sites. Helminths exhibit a sublime co-evolution with the host´s immune system that has enabled them to successfully colonize almost all multicellular species present in every geographical environment, including over two billion humans. In the face of this challenge, the host immune system has evolved to strike a delicate balance between attempts to neutralize the infectious assault versus limitation of damage to host tissues. Among the most important cell types during helminthic invasion are granulocytes: eosinophils, neutrophils and basophils. Depending on the specific context, these leukocytes may have pivotal roles in host protection, immunopathology, or facilitation of helminth establishment. This review provides an overview of the function of granulocytes in helminthic infections. PMID:22360486

In vivo effect of single oral dose of artemether against early juvenile stages of Schistosoma mansoni Egyptian strain.

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El-Beshbishi, Samar N; Taman, Amira; El-Malky, Mohamed; Azab, Manar S; El-Hawary, Amira K; El-Tantawy, Dina A

2013-10-01

The current treatment and control of schistosomiasis, rely on a single drug, praziquantel, although, it has minor activity against juvenile stages of the parasite. Studies have shown that artemether (ART) exhibits effects against juveniles of Schistosoma mansoni Liberian and Puerto Rican strains, Schistosoma japonicum and Schistosoma haematobium. Aiming to assess the in vivo activity of single oral dose of ART against early juvenile stages of S. mansoni Egyptian strain, this study was established. Mice were treated with ART (400 mg/kg) at two time points evenly spaced over the period of larval development (7 and 21 days post-infection; pi), and a third treatment point (day 49 pi) was included to elucidate when susceptibility decreases. Administration of ART on day 7 pi reduced the total worm burden by 85.94%. The greatest reductions were seen when treatment was given on day 21 pi, with total and female worm burden reductions of 91.52% and 90.57%, respectively, and cessation of oviposition. Similar dose given on day 49 pi reduced total worm burden by 55.17% and female worm burden by 66.51%. Moreover, it induced significant reduction in the tissue egg load and significant alterations in the oogram pattern with decreased immature eggs and increased dead eggs. Antipathological activities were evident in significant reductions in granulomata count and diameter. In conclusion, ART exhibits major in vivo schistosomicidal effects against the early larval migratory stages of S. mansoni Egyptian strain, mainly the 21-day old schistosomula, hence preventing disease progression and morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.

Platynosomum fastosum-induced chronic intrahepatic cholangitis and Spirometra spp. infections in feral cats from Grand Cayman.

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Headley, S A; Gillen, M A; Sanches, A W D; Satti, M Z

2012-06-01

The occurrence of platynosomiasis and intestinal sparganosis is described in feral cats from Grand Cayman, Cayman Islands. Spirometra spp. was observed within the intestine of 18.18% (10/55) of cats; 1.18% (1/55) of cats demonstrated gross and histological manifestation of parasitism by Platynosomum fastosum, but 14.5% (8/55) of cats had the characteristic pathological manifestations of P. fastosum-induced intrahepatic cholangitis without the concomitant presence of the intraductal trematode. Combined parasitism (Spirometra spp. and P. fastosum) was observed in 9.09% (5/55) of feral cats. Significant pathological findings were only associated with the hepatic fluke, P. fastosum, and were grossly characterized by moderate hepatomegaly with enlarged and dilated bile ducts. Examples of cestodes with morphological features characteristic of Spirometra spp. were observed within the small intestine without any associated pathological lesion. The histopathological evaluation of liver fragments revealed chronic intrahepatic cholangitis with and without the associated intraductal trematode, and was characterized by marked periductal fibrosis, adenomatous proliferation of bile duct epithelium, dilation of intrahepatic bile ducts and portal accumulations of inflammatory cells. The occurrence of the cestode in feral cats coupled with factors that are unique to Grand Cayman makes this island the ideal location for sporadic cases of human sparganosis.

Repurposing drugs for the treatment and control of helminth infections

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Gordana Panic

2014-12-01

Full Text Available Helminth infections are responsible for a considerable public health burden, yet the current drug armamentarium is small. Given the high cost of drug discovery and development, the high failure rates and the long duration to develop novel treatments, drug repurposing circumvents these obstacles by finding new uses for compounds other than those they were initially intended to treat. In the present review, we summarize in vivo and clinical trial findings testing clinical candidates and marketed drugs against schistosomes, food-borne trematodes, soil-transmitted helminths, Strongyloides stercoralis, the major human filariases lymphatic filariasis and onchocerciasis, taeniasis, neurocysticercosis and echinococcosis. While expanding the applications of broad-spectrum or veterinary anthelmintics continues to fuel alternative treatment options, antimalarials, antibiotics, antiprotozoals and anticancer agents appear to be producing fruitful results as well. The trematodes and nematodes continue to be most investigated, while cestodal drug discovery will need to be accelerated. The most clinically advanced drug candidates include the artemisinins and mefloquine against schistosomiasis, tribendimidine against liver flukes, oxantel pamoate against trichuriasis, and doxycycline against filariasis. Preclinical studies indicate a handful of promising future candidates, and are beginning to elucidate the broad-spectrum activity of some currently used anthelmintics. Challenges and opportunities are further discussed.

Taurine drinking ameliorates hepatic granuloma and fibrosis in mice infected with Schistosoma japonicum

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Yan-Rong Yu

2016-04-01

Full Text Available In schistosomiasis, egg-induced hepatic granuloma formation is a cytokine-mediated, predominantly CD4+ Th2 immune response that can give rise to hepatic fibrosis. Hepatic fibrosis is the main cause of increased morbidity and mortality in humans with schistosome infection. Taurine has various physiological functions and hepatoprotective properties as well as anti-inflammatory and immunomodulatory activity. However, little is known about the role of taurine in schistosome egg-induced granuloma formation and fibrosis. We aimed to evaluate the therapeutic potential of taurine as preventative treatment for Schistosoma japonicum infection. Mice infected with S. japonicum cercariae were supplied with taurine drinking water (1% w/v for 4 weeks starting at 4 weeks post-infection. Taurine supplementation significantly improved the liver pathologic findings, reduced the serum levels of aminotransferases and area of hepatic granuloma, and prevented fibrosis progression. In addition, taurine decreased the expression of the granulomatous and fibrogenic mediators transforming growth factor β1, tumor necrosis factor α, monocyte chemotactic protein 1α and macrophage inflammatory protein 1α as well as the endoplasmic reticulum stress marker glucose-regulated protein 78. Thus, taurine can significantly attenuate S. japonicum egg-induced hepatic granuloma and fibrosis, which may depend in part on the downregulation of some relevant cytokine/chemokines and reducing the endoplasmic reticulum stress response. Keywords: Schistosomiasis, Schistosoma japonicum, Granuloma, Fibrosis, Taurine

Development of Schistosoma incognitum in mice upon intraperitoneal inoculation with irradiated schistosomula

International Nuclear Information System (INIS)

Bhilegaonkar, N.G.; Sahasrabudhe, V.K.

1987-01-01

As a prelude to the study of the immunizing potential of gamma-irradiated Schistosoma incognitum schistosomula, experiments were conducted to study the effect of different doses of gamma irradiation (1,3,5 and 10 kr) on the development and survival of S. incognitum in mice, and its attendant pathology. The present experiments suggested that 3 and 5 kr irradiation doses can be safely used for irradiating schistosomula for immunization experiments in mice as the worms will not mature and therefore no harm will be caused which is mainly due to the eggs. (author). 7 refs

Estudios inmunologicos en hamsters (Cricetus auratus infectados con Schistosoma mansoni

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Eduardo Monge

1986-08-01

Full Text Available Los resultados de este trabajo muestran que el hamster (Cricetus auratus puede ser utilizado como un modelo experimental para estudios inmunológicos en la infección por Schistosoma mansoni. Los datos obtenidos, relativos a inmunidad concomitante, producción de anticuerpo letal e inmunosupresión se asemejan a los conseguidos en otros modelos experimentales ya establecidos. Estas observaciones indican que el hámster, además de ser un hospedero satisfactorio para el mantenimiento del parásito en el laboratorio, puede ser considerado como un modelo experimental alterno cuyo crecimiento y mantenimiento son relativamente simples y además es un animal de fácil manejo.

An artemisinin derivative of praziquantel as an orally active antischistosomal agent.

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Lanlan Dong

Full Text Available Schistosomiasis is a major health problem in tropical and sub-tropical areas caused by species of trematode belonging to the genus Schistosoma. The treatment and control of this disease has been relying on the use of a single drug praziquantel. However, the drug resistance concern urged the development of new drugs against schistosoma. Here, we report our systematic biological evaluation of DW-3-15, a new lead compound developed based on our conjugation design rationale as an effective anti-schistosomal agent.The antischistosomal activity of DW-3-15 was systematically evaluated in S. japonicum infected mouse model for its stage-sensitivity and dose response. The results revealed that DW-3-15 exhibited 60-85% worm reduction rate against different development stage of worm. Scanning electron microscopy (SEM observation indicated that DW-3-15 may damage to the tegument of male schistosomes.Our results demonstrated that DW-3-15 showed potent anti-schistosomal activities in vivo. The results strongly support our conjugation design strategy of artemisinin analogs and further development of DW-3-15 as a new lead compound as anti-schistosomal agent.

Host ploidy, parasitism and immune defence in a coevolutionary snail-trematode system.

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Osnas, E E; Lively, C M

2006-01-01

We studied the role of host ploidy and parasite exposure on immune defence allocation in a snail-trematode system (Potamopyrgus antipodarum-Microphallus sp.). In the field, haemocyte (the defence cell) concentration was lowest in deep-water habitats where infection is relatively low and highest in shallow-water habitats where infection is common. Because the frequency of asexual triploid snails is positively correlated with depth, we also experimentally studied the role of ploidy by exposing both diploid sexual and triploid asexual snails to Microphallus eggs. We found that triploid snails had lower haemocyte concentrations than did diploids in both parasite-addition and parasite-free treatments. We also found that both triploids and diploids increased their numbers of large granular haemocytes at similar rates after parasite exposure. Because triploid P. antipodarum have been shown to be more resistant to allopatric parasites than diploids, the current results suggest that the increased resistance of triploids is because of intrinsic genetic properties rather than to greater allocation to defence cells. This finding is consistent with recent theory on the advantages of increased ploidy for hosts combating coevolving parasites.

Schistosoma mansoni infection suppresses the growth of Plasmodium yoelii parasites in the liver and reduces gametocyte infectivity to mosquitoes.

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Taeko Moriyasu

2018-01-01

Full Text Available Malaria and schistosomiasis are major parasitic diseases causing morbidity and mortality in the tropics. Epidemiological surveys have revealed coinfection rates of up to 30% among children in Sub-Saharan Africa. To investigate the impact of coinfection of these two parasites on disease epidemiology and pathology, we carried out coinfection studies using Plasmodium yoelii and Schistosoma mansoni in mice. Malaria parasite growth in the liver following sporozoite inoculation is significantly inhibited in mice infected with S. mansoni, so that when low numbers of sporozoites are inoculated, there is a large reduction in the percentage of mice that go on to develop blood stage malaria. Furthermore, gametocyte infectivity is much reduced in mice with S. mansoni infections. These results have profound implications for understanding the interactions between Plasmodium and Schistosoma species, and have implications for the control of malaria in schistosome endemic areas.

Oogram studies in mice infected with Schistosoma mansoni and treated with dexamethasone Oograma em camundongos infectados com Schistosoma mansoni e tratados com dexametasona

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Marco Victor Hermeto

1994-04-01

Full Text Available Mice infected with about 90 cercariae of Schistosoma mansoni (LE strain were treated during five consecutive days with dexamethasone (50 mg/Kg, subcutaneously, starting on the 42th day of infection. Groups of five mice were then daily sacrificed from the first day after onset of treatment until the first day after. The perfusion of the portal system was performed and a piece of the intestine was processed for qualitative and quantitative oograms. This treatment carries to larger numbers of eggs in the tissues of treated mice, when compared with untreated groups. No changes were observed in the kinetics of oviposition, as all stages of viable eggs were observed in the tissues of treated and control mice. These data reinforce the hypothesis of a partial blockade of the egg excretion in immunossupressed mice.Camundongos infectados com cerca de 90 cercárias da cepa LE de Schistosoma mansoni foram tratados durante 5 dias consecutivos com dexametasona (50mg/ Kg, subcutaneamente a partir do 42º dia de infecção. Grupos de cinco camundongos foram sacrificados diariamente após o primeiro dia do início do tratamento até o primeiro dia após o término. A perfusão do sistema porta foi feita e fragmentos do intestino foram processados para a realização de oogramas qualitativos e quantitativos. O tratamento leva a um maior número de ovos nos tecidos dos camundongos tratados, se comparado com os grupos não tratados. Nenhuma mudança foi observada na cinética de oviposição, e ovos viáveis em todos os estádios evolutivos foram observados nos tecidos de camundongos tratados e controles. Estes dados reforçam a hipótese de um bloqueio parcial na saída de ovos dos tecidos do intestino para o lúmem intestinal em camundongos imunossuprimidos.

SjCRT, a recombinant Schistosoma japonicum calreticulin, induces maturation of dendritic cells and a Th1-polarized immune response in mice

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Lizhen Ma

2017-11-01

Full Text Available Abstract Background It is well known that immunization of radiation-attenuated (RA schistosoma cercariae or schistosomula can induce high levels of protective immunity against schistosoma cercariae reinfection in many animals. Many studies have shown that the Th1 cellular immune response is crucial for the protective effect elicited by RA schistosomula. However, the molecular mechanism of this strong protective immunity remains unclear. Methods The expression profiles of Schistosoma japonicum calreticulin (SjCRT in RA and normal schistosoma-derived cells were investigated by flow cytometry. The effect of recombinant SjCRT (rSjCRT on mouse dendritic cells (DCs was determined by FACS, ELISA and RT-PCR analysis. We also analyzed the effects of SjCRT on the activation of spleen cells from mice immunized with rSjCRT by detecting lymphocyte proliferation and the cytokine profiles of splenocytes. Results We found that the expression level of SjCRT in the cells from RA larvae was significantly higher than that in cells from normal schistosomula at early stages of development (day 4. The results of effect of rSjCRT on mouse DCs showed that rSjCRT could induce phenotypic and functional maturation of DCs, and SjCRT bound to the surface of DCs through the CD91 receptor and could be engulfed by DCs. The results of activation of splenocytes from mice immunized with rSjCRT also demonstrate that rSjCRT can effectively stimulate the proliferative response of splenic lymphocytes, elicit splenocytes from immunized mice to secrete high levels of IFN-γ, TNF-α and IL-4, and activate CD4+ T cells to produce high levels of IFN-γ. Conclusion SjCRT is one of the immunostimulatory molecules released from RA schistosomula cells, might play a crucial role in conferring a Th1-polarized immune response induced by RA cercariae/schistosomula in mice, and is a candidate molecule responsible for the high levels of protective immunity induced by RA schistosomula.

Defense response of susceptible and resistant Biomphalaria alexandrina snails against Schistosoma mansoni infection

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Iman F. Abou-El-Naga

2012-09-01

Full Text Available In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. The fates of Schistosoma miracidia in the snails varies between different species of Biomphalaria. The internal defense system is one of the factors that influence the susceptibility pattern of the snails. The interaction between Biomphalaria snails and S. mansoni needs to be identified for each species, and even between the members of the same species with different degrees of susceptibility. In the present study, the first generation of susceptible and resistant parents of B. alexandrina was examined histologically at the 30th day post exposure. The study includes the characterization of the immune response, as expressed by tissue reactions, of susceptible and resistant B. alexandrina snails against S. mansoni. It was also designed to determine the impact of the resistance increase in parent snails, on the mechanisms of interaction of their offspring against infection. The results showed that the infection rate of the offspring from the susceptible parents was 92%. No susceptible offspring was produced from the resistant parents. When the parents were of equal number of susceptible and resistant snails, they gave an offspring with an infection rate of 20%. Susceptible snails that had susceptible parents showed a higher degree of susceptibility than those that had both susceptible and resistant parents. A common feature of the resistant snails was the absence of any viable parasites. The tissue reactions of the resistant snails having only resistant parents occurred at the site of miracidial penetration. In resistant snails for which susceptible ones were included in their parents, the reactions occurred in the deep tissues. These results characterized the immune response of B. alexandrina snails against Schistosoma infection which was found to occur by two different mechanisms. One type of defense occurs in highly resistant snails, and employs direct

Epidemiological studies of Schistosoma mattheei infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

DEFF Research Database (Denmark)

Pfukenyi, D.M.; Mukaratirwa, S.; Willingham, Arve Lee

2006-01-01

there were peaks between March / May and September / November. The mean num ber of snails collected was positively correlated with the water plants Nymphaea caerulea and Typha species. Overall, 2.5 % of B. globosus were shedding Schistosoma cercariae. In the highveld, 2.8 % of B. globosus were infected...

DNA barcoding of schistosome cercariae reveals a novel sub-lineage within Schistosoma rodhaini from Ngamba Island Chimpanzee Sanctuary, Lake Victoria.

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Standley, C J; Stothard, J R

2012-10-01

While Schistosoma rodhaini is typically considered a parasite of small mammals and is very scantly distributed in the Lake Victoria basin, it is known to hybridize with the more widespread Schistosoma mansoni, the causative agent of intestinal schistosomiasis. As part of broader parasitological and malacological surveys for S. mansoni across Lake Victoria, schistosome cercariae were harvested from a field-caught Biomphalaria choanomphala taken on Ngamba Island Chimpanzee Sanctuary, Uganda. Upon DNA barcoding, these cercariae were found to be a mixture of both S. rodhaini and S. mansoni, with further phylogenetic analysis revealing a hitherto unknown sub-lineage within S. rodhaini. Despite repeated sampling for eggs and miracidia from both chimpanzees and staff on Ngamba Island Sanctuary, detection of S. rodhaini within local definitive hosts awaits additional efforts, which should be mindful of a potential host role of spotted-necked otters.

Phylogenetic characterization of Clonorchis sinensis proteins homologous to the sigma-class glutathione transferase and their differential expression profiles.

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Bae, Young-An; Kim, Jeong-Geun; Kong, Yoon

2016-01-01

Glutathione transferase (GST) is one of the major antioxidant proteins with diverse supplemental activities including peroxidase, isomerase, and thiol transferase. GSTs are classified into multiple classes on the basis of their primary structures and substrate/inhibitor specificity. However, the evolutionary routes and physiological environments specific to each of the closely related bioactive enzymes remain elusive. The sigma-like GSTs exhibit amino acid conservation patterns similar to the prostaglandin D synthases (PGDSs). In this study, we analyzed the phylogenetic position of the GSTs of the biocarcinogenic liver fluke, Clonorchis sinensis. We also observed induction profile of the GSTs in association with the parasite's maturation and in response to exogenous oxidative stresses, with special attention to sigma-class GSTs and PGDSs. The C. sinensis genome encoded 12 GST protein species, which were separately assigned to cytosolic (two omega-, one zeta-, two mu-, and five sigma-class), mitochondrial (one kappa-class), and microsomal (one membrane-associated proteins in eicosanoid and glutathione metabolism-like protein) GST families. Multiple sigma GST (or PGDS) orthologs were also detected in Opisthorchis viverrini. Other trematode species possessed only a single sigma-like GST gene. A phylogenetic analysis demonstrated that one of the sigma GST lineages duplicated in the common ancestor of trematodes were specifically expanded in the opisthorchiids, but deleted in other trematodes. The induction profiles of these sigma GST genes along with the development and aging of C. sinensis, and against various exogenous chemical stimuli strongly suggest that the paralogous sigma GST genes might be undergone specialized evolution to cope with the diverse hostile biochemical environments within the mammalian hepatobiliary ductal system. Copyright © 2016 Elsevier B.V. All rights reserved.

Anemia and growth retardation associated with Schistosoma haematobium infection in Mali

DEFF Research Database (Denmark)

Stecher, Chalotte W; Sacko, Moussa; Madsen, Henry

2017-01-01

BackgroundThe aim of this cross-sectional study was to investigate a possible association of Schistosoma haematobium with child growth development and describe a plausible schistosomiasis-related anemia in children and adults in a highly schistosomiasis endemic area of Mali. MethodsUrine, feces...... associated with anemia; i.e., odds of having anemia in the highest and the next highest category was 3.25 (95% CL 1.61–6.55; p... factors. Anemia was most pronounced in the 2–5 year olds males (55.5%, n=98). P. falciparum infection was not significantly associated with anemia. Stunting (body mass index [BMI] for age z-score

Molecular and structural characteristics of multidrug resistance-associated protein 7 in Chinese liver fluke Clonorchis sinensis.

Science.gov (United States)

Dai, Fuhong; Yoo, Won Gi; Lee, Ji-Yun; Lu, Yanyan; Pak, Jhang Ho; Sohn, Woon-Mok; Hong, Sung-Jong

2017-03-01

Multidrug resistance-associated protein 7 (MRP7, ABCC10) is a C subfamily member of the ATP-binding cassette (ABC) superfamily. MRP7 is a lipophilic anion transporter that pumps endogenous and xenobiotic substrates from the cytoplasm to the extracellular milieu. Here, we cloned and characterized CsMRP7 as a novel ABC transporter from the Chinese liver fluke, Clonorchis sinensis. Full-length cDNA of CsMRP7 was 5174 nt, encoded 1636 amino acids (aa), and harbored a 147-bp 5'-untranslated region (5'-UTR) and 116-bp 3'-UTR. Phylogenetic analysis confirmed that CsMRP7 was closer to the ABCC subfamily than the ABCB subfamily. Tertiary structures of the N-terminal region (1-322 aa) and core region (323-1621 aa) of CsMRP7 were generated by homology modeling using glucagon receptor (PDB ID: 5ee7_A) and P-glycoprotein (PDB ID: 4f4c_A) as templates, respectively. CsMRP7 nucleotide-binding domain 2 (NBD2) was conserved more than NBD1, which was the sites of ATP binding and hydrolysis. Like typical long MRPs, CsMRP7 has an additional membrane-spanning domain 0 (MSD0) and cytoplasmic loop, along with a common structural fold consisting of MSD1-NBD1-MSD2-NBD2 as a single polypeptide assembly. MSD0, MSD1, and MSD2 consisted of TM1-7, TM8-13, and TM14-19, respectively. The CsMRP7 transcript was more abundant in the metacercariae than in the adult worms. Truncated NBD1 (39 kDa) and NBD2 (44 kDa) were produced in bacteria and mouse immune sera were raised. CsMRP7 was localized in the apical side of the intestinal epithelium, sperm in the testes and seminal receptacle, receptacle membrane, and mesenchymal tissue around intestine in the adult worm. These results provide molecular information and insights into structural and functional characteristics of CsMRP7 and homologs of flukes.

The mitochondrial genome of Paragonimus westermani (Kerbert, 1878, the Indian isolate of the lung fluke representative of the family Paragonimidae (Trematoda

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Devendra K. Biswal

2014-08-01

Full Text Available Among helminth parasites, Paragonimus (zoonotic lung fluke gains considerable importance from veterinary and medical points of view because of its diversified effect on its host. Nearly fifty species of Paragonimus have been described across the globe. It is estimated that more than 20 million people are infected worldwide and the best known species is Paragonimus westermani, whose type locality is probably India and which infects millions of people in Asia causing disease symptoms that mimic tuberculosis. Human infections occur through eating raw crustaceans containing metacercarie or ingestion of uncooked meat of paratenic hosts such as pigs. Though the fluke is known to parasitize a wide range of mammalian hosts representing as many as eleven families, the status of its prevalence, host range, pathogenic manifestations and its possible survivors in nature from where the human beings contract the infection is not well documented in India. We took advantage of the whole genome sequence data for P. westermani, generated by Next Generation Sequencing, and its comparison with the existing data for the P. westermani for comparative mt DNA phylogenomic analyses. Specific primers were designed for the 12 protein coding genes with the aid of existing P. westermani mtDNA as the reference. The Ion torrent next generation sequencing platform was harnessed to completely sequence the mitochondrial genome, and applied innovative approaches to bioinformatically assemble and annotate it. A strategic PCR primer design utilizing the whole genome sequence data from P. westermani enabled us to design specific primers capable of amplifying all regions of the mitochondrial genome from P. westermani. Assembly of NGS data from libraries enriched in mtDNA sequence by PCR gave rise to a total of 11 contigs spanning the entire 14.7 kb mt DNA sequence of P. westermani available at NCBI. We conducted gap-filling by traditional Sanger sequencing to fill in the gaps

Schistosoma haematobium infection and asymptomatic bacteriuria in young South African females

DEFF Research Database (Denmark)

Kildemoes, Anna M. O.; Kjetland, Eyrun Floerecke; Zulu, Siphosenkosi Gift

2015-01-01

Schistosoma haematobium eggs can induce lesions in the urinary and genital tract epithelia, as eggs pass through or get trapped in the tissue. Local inflammatory reactions induced by S. haematobium eggs might affect the ability of bacteria to establish mucosal super-infection foci. S. haematobium...... school students from a schistosomiasis endemic area in KwaZulu-Natal, South Africa. Furthermore, it was demonstrated that asymptomatic bacteriuria is not a bias for use of micro-haematuria as a proxy diagnostic measure for S. haematobium infection in this population....

The potential for using red claw crayfish and hybrid African catfish as biological control agents for Schistosoma host snails

NARCIS (Netherlands)

Monde, C.; Syampungani, S.; Rico, A.; Brink, van den P.J.

2017-01-01

The potential of red claw crayfish and hybrid African catfish (Clarias gariepinus and Clarias ngamensis) as predators for Schistosoma host snails was evaluated in 2014 by monitoring the consumption of snails by crayfish and catfish in experimental tanks over time under laboratory conditions. After

Two-year intervention trial to control of fish-borne zoonotic trematodes in giant gourami (Osphronemus goramy) and striped catfish (Pangasianodon hypophthalmus) in nursery ponds in the Mekong Delta, Vietnam

DEFF Research Database (Denmark)

Madsen, Henry; Thien, P. C.; Nga, H. T. N.

2015-01-01

Fish-borne zoonotic trematode parasites (FZT) pose a food safety and public health problem in Vietnam. The transmission cycle is complex as domestic animals, especially dogs, cats, fish-eating birds and pigs together with humans serve as reservoir hosts and contribute to FZT egg contamination of ...

New insights into the genetic diversity of Schistosoma mansoni and S. haematobiumin Yemen.

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Sady, Hany; Al-Mekhlafi, Hesham M; Webster, Bonnie L; Ngui, Romano; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Chua, Kek Heng; Lim, Yvonne A L; Surin, Johari

2015-10-20

Human schistosomiasis is a neglected tropical disease of great importance that remains highly prevalent in Yemen, especially amongst rural communities. In order to investigate the genetic diversity of human Schistosoma species, a DNA barcoding study was conducted on S. mansoni and S. haematobium in Yemen. A cross-sectional study was conducted to collect urine and faecal samples from 400 children from five provinces in Yemen. The samples were examined for the presence of Schistosoma eggs. A partial fragment of the schistosome cox1 mitochondrial gene was analysed from each individual sample to evaluate the genetic diversity of the S. mansoni and S. haematobium infections. The data was also analysed together with previous published cox1 data for S. mansoni and S. haematobium from Africa and the Indian Ocean Islands. Overall, 31.8 % of participants were found to be excreting schistosome eggs in either the urine or faeces (8.0 % S. mansoni and 22.5 % S. haematobium). Nineteen unique haplotypes of S. mansoni were detected and split into four lineages. Furthermore, nine unique haplotypes of S. haematobium were identified that could be split into two distinct groups. This study provides novel and interesting insights into the population diversity and structure of S. mansoni and S. haematobium in Yemen. The data adds to our understanding of the evolutionary history and phylogeography of these devastating parasites whilst the genetic information could support the control and monitoring of urogenital and intestinal schistosomiasis in these endemic areas.

Expanding the Therapeutic Spectrum of Artemisinin: Activity Against Infectious Diseases Beyond Malaria and Novel Pharmaceutical Developments

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Thomas Efferth

2016-08-01

Full Text Available The interest of Western medicine in Traditional Chinese Medicine (TCM as a source of drug leads/new drugs to treat diseases without available efficient therapies has been dramatically augmented in the last decades by the extensive work and the outstanding findings achieved within this kind of medicine. The practice of TCM over thousands of years has equipped scientists with substantial experience with hundreds of plants that led to the discovery of artemisinin (qinghaosu, which is extracted from the medicinal plant Artemisia annua L. (qinghao. The unexpected success of artemisinin in combating malaria has drawn strong attention from the scientific community towards TCM. Artemisinin was discovered by Youyou Tu in 1972. Since then, several novel pharmacological activities based on the well-known properties of the sesquiterpene lactone structure with the oxepane ring and an endoperoxide bridge have been unravelled. Beyond malaria, artemisinin and its derivatives (artemisinins exert profound activities towards other protozoans (Leishmania, Trypanosoma, amoebas, Neospora caninum, and Eimeria tenella, trematodes (Schistosoma, liver flukes, and viruses (human cytomegalovirus, hepatitis B and C viruses. Less clear is the effect against bacteria and fungi. Based on the promising results of artemisinin and the first generation derivatives (artesunate, artemether, arteether, novel drug development strategies have been pursued. These included the synthesis of acetal- and non-acetal-type artemisinin dimeric molecules as well as developing nanotechnological approaches, e.g. artemisinin-based liposomes, niosomes, micelles, solid lipid nanocarriers, nanostructured lipid carriers, nanoparticles, fullerenes and nanotubes. The current review presents an overview on different aspects of artemisinins, including sources, chemistry, biological/pharmacological properties, types of infectious pathogens that are susceptible to artemisinins in vitro and in vivo, in

Novel SINE families from salmons validate Parahucho (Salmonidae) as a distinct genus and give evidence that SINEs can incorporate LINE-related 3'-tails of other SINEs.

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Matveev, Vitaliy; Nishihara, Hidenori; Okada, Norihiro

2007-08-01

Short interspersed elements (SINEs) constitute a group of retroposons propagating in the genome via a mechanism of reverse transcription, in which they depend on the enzymatic machinery of long retroposons (LINEs). Over 70 SINE families have been described to date from the genomes of various eukaryotes. Here, we characterize two novel SINEs from salmons (Actinopterygii: Salmonoidei). The first family, termed SlmI, was shown to be widespread among all genera of the suborder. These SINEs have a tRNA(Leu)-related promoter region at their 5'-end, a unique central conserved domain with a subfamily-specific region, and an end with RSg-1-LINE-derived 3'-terminus preceding the A/T-rich tail. The same LINE-related segment is also shared by two other salmonid SINEs: HpaI and OS-SINE1. The structural peculiarities and overall sequence identity of the SlmI 3'-terminus suggest that it has been acquired from HpaI SINEs but not directly from the partner LINE. This region plays a crucial role in the process of retrotransposition of short interspersed elements, and the case of its SINE-to-SINE transmission is the first recorded to date. Possible scenarios and potential evolutionary implications of the observed interaction between short retroposons are discussed. Apart from the above, we found a copy of the SlmI SINE in the GenBank entry for the blood fluke, Schistosoma japonicum (Trematoda: Strigeiformes) -- a trematode causing one of the most important human helminth infections, with its genome known to host other groups of salmonoid retroposons. In the present article, we suggest our views with regard to possible ways in which such an intensive horizontal transfer of salmonoid retroposons to the schistosomal genome occurs. The second novel SINE family, termed SlmII, originates from one of the SlmI subfamilies, with which it shares the same tRNA-related region, central domain, and a part of RSg-1-derived segment, but has a different 3'-tail of unidentified origin. Its distribution

Larval trematodes (Digenea of the great pond snail, Lymnaea stagnalis (L., (Gastropoda, Pulmonata in Central Europe: a survey of species and key to their identification

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Faltýnková A.

2007-03-01

Full Text Available A survey of cercariae and metacercariae (Trematoda, Digenea from the great pond snail (Lymnaea stagnalis in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3% L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected, Plagiorchis elegans (141 (both family Plagiorchiidae and Echinoparyphium aconiatum (153 (Echinostomatidae; 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71 (Omphalometridae, E. aconiatum (66, Echinostoma sp. (59 and Moliniella anceps (48 (Echinostomatidae. In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided.

Comparative Evaluation of Anthelmintic Activity of Edible and Ornamental Pomegranate Ethanolic Extracts against Schistosoma mansoni

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Doaa A. Yones

2016-01-01

Full Text Available Due to the development of praziquantel (PZQ schistosomes resistant strains, the discovery of new antischistosomal agents is of high priority in research. This work reported the in vitro and in vivo effects of the edible and ornamental pomegranate extracts against Schistosoma mansoni. Leaves and stem bark ethanolic extracts of both dried pomegranates were prepared at 100, 300, and 500 μg/mL for in vitro and 600 and 800 mg/kg for in vivo. Adult worms Schistosoma mansoni in RPMI-1640 medium for in vitro and S. mansoni infected mice for in vivo tests were obtained from Theodor Bilharz Research Institute, Cairo, Egypt. In vitro activity was manifested by significant coupled worms separation, reduction of motor activity, lethality, and ultrastructural tegumental alterations in adult worms. In vivo activity was manifested revealed by significant reduction of hepatic granulomas number and diameter, decreased number of bilharzial eggs in liver tissues, lowered liver inflammatory infiltration, decreased hepatic fibrosis, and inducible nitric oxide synthase (iNOS expression. Ethanolic stem bark extract of edible pomegranate exhibited highest antischistosomal activities both in vitro and in vivo. Therefore, pomegranate showed a good potential to be used as a promising new candidate for the development of new schistosomicidal agents.

Angiogenesis in Schistosoma haematobium-associated urinary bladder cancer.

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Dematei, Anderson; Fernandes, Rúben; Soares, Raquel; Alves, Helena; Richter, Joachim; Botelho, Monica C

2017-12-01

Schistosoma haematobium, a parasitic flatworm that infects more than 100 million people, mostly in the developing world, is the causative agent of urogenital schistosomiasis, and is associated with a high incidence of squamous cell carcinoma (SCC) of the bladder. During infection, eggs are deposited in the bladder causing an intense inflammatory reaction. Angiogenesis is defined as the formation of new blood vessels from preexisting ones and is recognized as a key event in cell proliferation and carcinogenesis and spread of malignant lesions. A growing amount of evidence points to angiogenesis playing a key role in schistosomiasis-associated bladder cancer. Thus, identifying biomarkers of this process plays an important role in the study of cancer. Here, we review recent findings on the role of angiogenesis in bladder cancer and the growth factors that induce and assist in their development, particularly SCC of the bladder associated to urogenital schistosomiasis. © 2017 APMIS. Published by John Wiley & Sons Ltd.

Massa tumoral secundária a infecção por Schistosoma mansoni simulando neoplasia de pulmão: relato de caso Tumoral pulmonary mass secondary to Schistosoma mansoni infection resembling neoplasia: case report

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Cláudio Dornas de Oliveira

2009-12-01

Full Text Available Indivíduos infectados com Schistosoma mansoni na fase crônica da doença podem apresentar comprometimento pulmonar com sintomatologia e alterações radiológicas variáveis. Os pulmões podem ser acometidos pela migração anômala de ovos do sistema porta para o sistema arterial pulmonar (através de anastomoses porto-sistêmicas e menos comumente por migrações ectópicas de vermes adultos. Há casos com extenso comprometimento parenquimatoso e outros com predomínio de arterites, com hipertensão pulmonar e cor pulmonale. Paciente jovem, residente em área endêmica de esquistossomose, com massa pulmonar sugestiva de neoplasia foi submetida a toracotomia exploradora sem possibilidade de ressecção da massa. Exame histopatológico mostrou vários granulomas esquistossomóticos e hiperplasia do tecido conjuntivo, sem sinais de neoplasia. Evoluiu com insuficiência respiratória e instabilidade hemodinâmica no pós-operatório imediato. Recebeu tratamento específico (praziquantel associado a prednisona. A paciente cursou com infecção pulmonar e choque séptico. Recebeu antibioticoterapia, aminas vasoativas, suporte ventilatório e tratamento hemodiálitico sem melhora. Evoluiu para óbito 28 dias após cirurgia.Patients with chronic Schistosoma mansoni infection may feature a range of pulmonary symptoms and radiological findings. Eggs, and rarely adult worms, may passively enter the pulmonary circulation, usually via the portal system, where they may cause pulmonary inflammation, fibrosis, hypertension and cor pulmonale. A 25-year-old patient who lived in a schistosomiasis endemic area with a pulmonary mass suggestive of malignancy underwent exploratory thoracotomy. The mass was adherent, with no resection possibility. The lung-biopsy specimen evaluation showed several granulomas with Schistosoma mansoni eggs and hyperplasic connective tissue with no sign of malignancy. The patient had respiratory failure and hypotension immediately

Human Schistosoma haematobium antifecundity immunity is dependent on transmission intensity and associated with immunoglobulin G1 to worm-derived antigens

DEFF Research Database (Denmark)

Wilson, Shona; Jones, Frances M.; van Dam, Govert J.

2014-01-01

BACKGROUND: Immunity that reduces worm fecundity and, in turn, reduces morbidity is proposed for Schistosoma haematobium, a parasite of major public health importance. Mathematical models of epidemiological trends suggest that antifecundity immunity is dependent on antibody responses to adult......-worm-derived antigen. METHODS: For a Malian cohort (age, 5-29 years) residing in high-transmission fishing villages or a moderate-transmission village, worm fecundity was assessed using the ratio of urinary egg excretion to levels of circulating anodic antigen, a Schistosoma-specific antigen that is steadily secreted......, host age and transmission were negatively associated with worm fecundity. A significant interaction term between host age and transmission indicates that antifecundity immunity develops earlier in high-transmission areas. SWA immunoglobulin G1 (IgG1) levels explained the effect of transmission...

Vitamin E reduces hepatic fibrosis in mice with Schistosoma japonicum infection.

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Wang, Xuefeng; Zhang, Rongbo; Du, Jiuwei; Hu, Youying; Xu, Lifa; Lu, Jun; Ye, Song

2012-02-01

To investigate whether vitamin E protects against hepatic fibrosis in mice with Schistosoma japonicum infection, 24 pathogen-free Kunming mice were selected and randomly divided into four groups: control (uninfected, untreated), model (infected, untreated), low-dose intervention (infected, vitamin E-treated, 30 mg/g bodyweight/day) and high-dose intervention (infected, vitamin E-treated, 60 mg/g bodyweight/day). Mice were infected with Schistosoma japonicum by inoculating abdominal skin with snail hosts. The activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were detected in hepatic tissue by colorimetry. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type Ⅲ (PC-III) and type Ⅳ collagen (IV-C) were detected in the serum by radioimmunoassay. Finally, areas and numbers of granulomas were assessed through histopathology 42 days following treatment. The results revealed that mean areas of granulomas were smaller in the low- and high-dose intervention groups compared to those in the model group. Furthermore, the higher dose of vitamin E resulted in smaller granulomas than the low dose. The levels of LN, HA, PC-III and IV-C in the serum were lower following vitamin E treatment than in the model group. By contrast, activity of SOD, GPx and CAT in hepatic tissue was higher following vitamin E treatment compared to the model group. The activity of MDA was lower in hepatic tissue following vitamin E treatment compared to the model group, but was higher compared to controls. In general, the higher dose of vitamin E affected measurements to a greater extent than the lower dose. In conclusion, vitamin E treatment may reduce the growth of granulomas, slowing the process of hepatic fibrosis, and this effect may be the result of the altered activity of the oxidation-reduction enzyme system.

PCR-based detection of Schistosoma bovis in cattle in Maiduguri Metropolis and Jere Local Government Areas in Borno State, Nigeria

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Idris Umar Hambali

2016-06-01

Results: The overall prevalence of Schistosoma infection was 2% (n=200. Jere LGA had 3% (n=100 while MMC had 1% (n=100. There was no statistical significant association in prevalence rate in the two LGAs studied (P=0.621 (P>0.05. At the ward levels, Custom Area in Jere LGA had 15%, Jiddari ward in MMC had 5%, and the remaining ward levels had no cases. Of the 103 female and 97 male cattle screened, the prevalence in female was 1(0.97% and 3(3.09% in the male. Of the 177 serum samples from above 1year (adult examined, 4 (2.26% were positive and none in the young. There was no statistical significant association in prevalence rate among ward levels, sex groups and age groups in the study areas (P=0.621 (P>0.05, (P=0.356 (P>0.05 and (P=1.000 (P>0.05 respectively. Of the eight (8 breeds screened, Kuri had 2.7%, Sokoto Gudali (1.82%, Abore (2%, Red Bororo (2.63%, White Fulani, Porland, Mbala and Wafara recorded no cases. The difference in prevalence rates among the breeds based on the trend of occurrence of Schistosoma infection were not significantly associated statistically (P=1.000 (P>0.05. Conclusion: There is a prevalence of Schistosoma infection in cattle in the two LGAs of Borno state. It is recommended that a system be established to maintain preventive and control programs. [J Adv Vet Anim Res 2016; 3(2.000: 92-98

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa).

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Benamrouz, S; Conseil, V; Creusy, C; Calderon, E; Dei-Cas, E; Certad, G

2012-05-01

The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites) with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

Change in schistosome sex ratio under the influence of a biotic environmental-related factor.

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Moné, H

1997-04-01

Schistosoma mansoni is a dioecious trematode responsible for intestinal schistosomiasis in man. The sex ratio was determined for S. mansoni adults derived from cercariae obtained from infected Biomphalaria glabrata maintained in the presence of the nonvector molluse. Marisa cornuarietis. The presence of M. cornuarietis is responsible for enhanced growth of B. glabrata and for a change in the sex ratio of the schistosome, which becomes more male-biased as compared to control snails maintained in aquaria lacking M. cornuarietis. This is the first time the presence of another species in the environment has been shown to influence schistosome sex ratios. Two nonexclusive hypotheses are proposed to explain this variation in the sex ratio: sexual competition between male and female sporocysts; and sex reversal.

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa

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Benamrouz S.

2012-05-01

Full Text Available The International Agency for Research on Cancer (IARC identifies ten infectious agents (viruses, bacteria, parasites able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

Long-term frozen storage of urine samples: a trouble to get PCR results in Schistosoma spp. DNA detection?

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Fernández-Soto, Pedro; Velasco Tirado, Virginia; Carranza Rodríguez, Cristina; Pérez-Arellano, José Luis; Muro, Antonio

2013-01-01

Human schistosomiasis remains a serious worldwide public health problem. At present, a sensitive and specific assay for routine diagnosis of schistosome infection is not yet available. The potential for detecting schistosome-derived DNA by PCR-based methods in human clinical samples is currently being investigated as a diagnostic tool with potential application in routine schistosomiasis diagnosis. Collection of diagnostic samples such as stool or blood is usually difficult in some populations. However, urine is a biological sample that can be collected in a non-invasive method, easy to get from people of all ages and easy in management, but as a sample for PCR diagnosis is still not widely used. This could be due to the high variability in the reported efficiency of detection as a result of the high variation in urine samples' storage or conditions for handling and DNA preservation and extraction methods. We evaluate different commercial DNA extraction methods from a series of long-term frozen storage human urine samples from patients with parasitological confirmed schistosomiasis in order to assess the PCR effectiveness for Schistosoma spp. detection. Patients urine samples were frozen for 18 months up to 7 years until use. Results were compared with those obtained in PCR assays using fresh healthy human urine artificially contaminated with Schistosoma mansoni DNA and urine samples from mice experimentally infected with S. mansoni cercariae stored frozen for at least 12 months before use. PCR results in fresh human artificial urine samples using different DNA based extraction methods were much more effective than those obtained when long-term frozen human urine samples were used as the source of DNA template. Long-term frozen human urine samples are probably not a good source for DNA extraction for use as a template in PCR detection of Schistosoma spp., regardless of the DNA method of extraction used.

Micro-geographical heterogeneity in Schistosoma mansoni and S. haematobium infection and morbidity in a co-endemic community in northern Senegal.

NARCIS (Netherlands)

Meurs, L.; Mbow, M.; Boon, N.; Van den Broeck, F.; Vereecken, K.; Dieye, T.N.; Abatih, E.; Huyse, T.; Mboup, S.; Polman, K.

2013-01-01

Background:Schistosoma mansoni and S. haematobium are co-endemic in many areas in Africa. Yet, little is known about the micro-geographical distribution of these two infections or associated disease within such foci. Such knowledge could give important insights into the drivers of infection and

The effect of treatment on the age-antibody relationship in children infected with Schistosoma mansoni and Schistosoma haematobium

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Mutapi Francisca

2002-01-01

Full Text Available The effect of praziquantel treatment on the age-antibody relationship was studied in 174 children aged between 6 and 17 years from a schistosome endemic area in Zimbabwe. The children were co-infected with Schistosoma mansoni and S. haematobium with infection prevalences of 74% and 53% respectively. Antibody levels for the isotypes IgA, IgE, IgM, IgG1, IgG2, IgG3 and IgG4, directed against soluble egg antigen were measured using an indirect ELISA assay. Treatment resulted in a significant increase in levels of IgG2 and IgG3 while levels of IgA decreased significantly. In untreated children there were significant decreases in levels of IgG4. Treatment also resulted in significant alteration in the age-antibody profiles for the isotypes IgE, IgM, IgG1 and IgG2 in treated children but not in untreated children. The results are discussed in the context of factors believed to give rise to the age-antibody relationship; i.e. age-related exposure patterns, age-related development of acquired immunity, age-related hormonal changes and age-related changes in innate susceptibility to infection.

Paramphistomum cervi: surface topography of the tegument of adult fluke.

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Panyarachun, Busaba; Sobhon, Prasert; Tinikul, Yotsawan; Chotwiwatthanakun, Charoonroj; Anupunpisit, Vipavee; Anuracpreeda, Panat

2010-06-01

Adult Paramphistomum cervi or rumen fluke are pear-shaped, slightly concave ventrally and convex dorsally. The worm measures about 5-13 mm in length and 2-5 mm in width across the mid-section. As observed by scanning electron microscopy (SEM), the tegumental surface in all part of the body, appears highly corrugated with transverse folds alternating with grooves and is spineless. At high magnification, the surface of the fold is composed of microfolds or ridges separated by microgrooves or pits. Corrugations and invaginations of the ventral surface are also more extensive than on the dorsal surface of the body. Both anterior and posterior suckers have thick rims covered with transverse folds without spine. The genital pore is situated at the anterior third of the body. There are two types of sensory papillae on the surface: type 1 is bulbous in shape, measuring 10-15 microm in diameter at the base with nipple-like tips, and type 2 has a similar shape and size and also a short cilia on top. These sensory papillae usually occur in large clusters, each having between 5 and 20 units depending on the region of the body. Clusters of papillae on the ventral surface and around the anterior suckers tend to be more numerous and larger in size. The dorsal surface of the body has the least number of papillae. Copyright (c) 2009 Elsevier Inc. All rights reserved.

Trematode infection modulates cockles biochemical response to climate change.

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Magalhães, Luísa; de Montaudouin, Xavier; Figueira, Etelvina; Freitas, Rosa

2018-05-06

Resulting mainly from atmospheric carbon dioxide (CO 2 ) build-up, seawater temperature rise is among the most important climate change related factors affecting costal marine ecosystems. Global warming will have implications on the water cycle, increasing the risk of heavy rainfalls and consequent freshwater input into the oceans but also increasing the frequency of extreme drought periods with consequent salinity increase. For Europe, by the end of the century, projections describe an increase of CO 2 concentration up to 1120 ppm (corresponding to 0.5 pH unit decrease), an increase in the water temperature up to 4 °C and a higher frequency of heavy precipitation. These changes are likely to impact many biotic interactions, including host-parasite relationships which are particularly dependent on abiotic conditions. In the present study, we tested the hypothesis that the edible cockle, Cerastoderma edule, exposed to different salinity, temperature and pH levels as proxy for climate change, modify the infection success of the trematode parasite Himasthla elongata, with consequences to cockles biochemical performance. The results showed that the cercariae infection success increased with acidification but higher biochemical alterations were observed in infected cockles exposed to all abiotic experimental stressful conditions tested. The present study suggested that changes forecasted by many models may promote the proliferation of the parasites infective stages in many ecosystems leading to enhanced transmission, especially on temperate regions, that will influence the geographical distribution of some diseases and, probably, the survival capacity of infected bivalves. Copyright © 2018 Elsevier B.V. All rights reserved.

High prevalence of the liver fluke Amphimerus sp. in domestic cats and dogs in an area for human amphimeriasis in Ecuador.

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Manuel Calvopiña

2015-02-01

Full Text Available Amphimerus sp. is a liver fluke which recently has been shown to have a high prevalence of infection among an indigenous group, Chachi, who reside in a tropical rainforest in the northwestern region of Ecuador. Since it is unknown which animals can act as a reservoir and/or definitive hosts for Amphimerus sp. in this endemic area, a study was done to determine the prevalence of infection in domestic cats and dogs. This information is important to understand the epidemiology, life cycle and control of this parasite.In July 2012, three Chachi communities located on Rio Cayapas, province of Esmeraldas, were surveyed. A total of 89 of the 109 registered households participated in the study. Of the 27 cats and 43 dogs found residing in the communities, stool samples were collected from 14 cats and 31 dogs (total of 45 animals and examined microscopically for the presence of Amphimerus eggs. The prevalence of infection was 71.4% in cats and 38.7% in dogs, with similar rates of infection in all three communities. Significantly more cats were infected than dogs (p = 0.042.The data show a high rate of Amphimerus sp. infection in domestic cats and dogs residing in Chachi communities. It can be concluded that these animals act as definitive and reservoir hosts for this liver fluke and that amphimeriasis is a zoonotic disease. These findings provide important epidemiological data which will aid in the development and implementation of control strategies against the transmission of Amphimerus.

Schistosome circulating anodic antigen in serum of individuals infected with Schistosoma japonicum from the Philippines before and after chemotherapy with praziquantel

NARCIS (Netherlands)

van 't Wout, A. B.; de Jonge, N.; Tiu, W. U.; Garcia, E. E.; Mitchell, G. F.; Deelder, A. M.

1992-01-01

The presence of the schistosome circulating anodic antigen (CAA) in serum of patients infected with Schistosoma japonicum from The Philippines has been investigated using an enzyme-linked immunosorbent assay (ELISA). Serum samples were tested from 48 patients who excreted S. japonicum eggs, 9

Epidemiological studies of Schistosoma mattheei infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

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D.M. Pfukenyi

2006-09-01

Full Text Available During the period between January 1999 and December 2000, the distribution and seasonal patterns of Schistosoma mattheei infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe were determined through monthly coprological examination. Faecal samples of cattle were collected from 12 and nine dipping sites in the highveld and lowveld communal grazing areas, respectively. Patterns of distribution and seasonal fluctuations of the intermediate host-snail populations and the climatic factors influencing the distribution were also determined at monthly intervals from November 1998 to October 2000, a period of 24 months, in six dams and six streams in the highveld and nine dams in the lowveld communal grazing areas. Monthly, each site was sampled for relative snail density, the vegetation cover and type, and physical and chemical properties of the water. Mean monthly rainfall and temperature were recorded. Snails collected at the same time were individually examined for shedding of cercariae of S. mattheei and Schistosoma haematobium. A total of 16 264 (5 418 calves, 5 461 weaners and 5 385 adults faecal samples were collected during the entire period of study and 734 (4.5 % were positive for S. mattheei eggs. Significantly higher prevalences were found in the highveld compared to the lowveld (P < 0.001, calves compared to adult cattle (P < 0.01 and the wet season compared to the dry season (P < 0.01. Faecal egg output peaked from October/ November to March / April for both years of the study. Bulinus globosus, the snail intermediate host of S. mattheei was recorded from the study sites with the highveld having a significantly higher abundance of the snails than the lowveld (P < 0.01. Monthly densities of B. globosus did not show a clearcut pattern although there were peaks between March / May and September / November. The mean num ber of snails collected was positively correlated with the water plants Nymphaea caerulea and

Population dynamics of the minute intestinal trematode Haplorchis pumilio following experimental infection of young dogs

DEFF Research Database (Denmark)

Nissen, Sofie; Nguyen, Lan Anh; Thamsborg, Stig Milan

2011-01-01

technique, temperature and weight of the dogs were measured as was total white blood cells, eosinophils and microhaemotocrit values. Subsets of dogs were examined post-mortem for presence of adult FZT at three different time points post infection. Patent infections established in all eight infected dogs......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on domestic animal’s role in the transmission of FZT in Northern Vietnam found that the most prevalent FZT was Haplorchis pumilio. The importance of dogs, cats and pigs was assessed, and dogs were found...... to have the highest intensity of infection and contribute the most to the contamination of the environment with FZT eggs in the Nam Dinh province - a highly endemic area for FZTs. Given the free roaming and fish-eating behaviour of many dogs in rural Vietnam controlling the infection in dogs represents...

New perspectives on host-parasite interplay by comparative transcriptomic and proteomic analyses of Schistosoma japonicum.

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Feng Liu

2006-04-01

Full Text Available Schistosomiasis remains a serious public health problem with an estimated 200 million people infected in 76 countries. Here we isolated ~ 8,400 potential protein-encoding cDNA contigs from Schistosoma japonicum after sequencing circa 84,000 expressed sequence tags. In tandem, we undertook a high-throughput proteomics approach to characterize the protein expression profiles of a number of developmental stages (cercariae, hepatic schistosomula, female and male adults, eggs, and miracidia and tissues at the host-parasite interface (eggshell and tegument by interrogating the protein database deduced from the contigs. Comparative analysis of these transcriptomic and proteomic data, the latter including 3,260 proteins with putative identities, revealed differential expression of genes among the various developmental stages and sexes of S. japonicum and localization of putative secretory and membrane antigens, enzymes, and other gene products on the adult tegument and eggshell, many of which displayed genetic polymorphisms. Numerous S. japonicum genes exhibited high levels of identity with those of their mammalian hosts, whereas many others appeared to be conserved only across the genus Schistosoma or Phylum Platyhelminthes. These findings are expected to provide new insights into the pathophysiology of schistosomiasis and for the development of improved interventions for disease control and will facilitate a more fundamental understanding of schistosome biology, evolution, and the host-parasite interplay.

Cytokine mRNA profiles in pigs exposed prenatally and postnatally to Schistosoma japonicum

DEFF Research Database (Denmark)

Techau, Michala E.; Johansen, Maria V.; Aasted, Bent

2007-01-01

of septal fibrosis were significantly higher in the postnatal group compared to the prenatal group (P prenatally infected animals compared to the control...... group (P prenatal group showed higher levels of TGF-beta 1 in the liver compared with the postnatally infected group (P control group (P prenatally exposed pigs.......The pig is a natural host for Schistosoma japonicum and a useful animal model of human infection. The aim of the present study was to assess the differences between the cytokine profiles in prenatally or postnatally S. japonicum exposed pigs. Seven prenatally exposed pigs, 7 postnatally exposed...

Zoonotic helminths parasites in the digestive tract of feral dogs and cats in Guangxi, China.

Science.gov (United States)

Fang, Fang; Li, Jian; Huang, Tengfei; Guillot, Jacques; Huang, Weiyi

2015-08-16

In Guangxi, a province of southern China, an important number of dogs and cats roam freely in rural settings, and the presence of these animals in proximity of people may represent a risk of parasitic zoonoses. The objective of the present study was to investigate the presence and identify gastrointestinal helminths in feral carnivores in Guangxi province. Therefore, post mortem examination was performed in 40 dogs and in 39 cats. The Gastrointestinal helminths were found in all the necropsied dogs and in 37 out of 39 cats. Fifteen species were identified including 7 trematodes, 3 cestodes and 5 nematodes. Most of them may be responsible for zoonotic infections. Major zoonotic gastrointestinal helminths, including liver and intestinal flukes, Toxocara spp., and Ancylostoma spp., are present in feral dogs and cats in Guangxi, and may represent a significant risk for public health.

Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs

NARCIS (Netherlands)

Smit, C.H.; van Diepen, A.; Nguyen, D.L.; Wuhrer, M.; Hoffmann, K.F.; Deelder, A.M.; Hokke, C.H.

2015-01-01

Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles

Seasonal pattern of Fasciola hepatica antibodies in dairy herds in Northern Germany.

Science.gov (United States)

Kuerpick, Birte; Schnieder, Thomas; Strube, Christina

2012-09-01

Fasciolosis, caused by the liver fluke Fasciola hepatica, is one of the most important parasitoses in cattle farming worldwide. In dairy cows, the trematode leads to economic losses due to decreased milk yield, a negative impact on reproduction parameters, and liver condemnations. In the present study, the seasonal patterns of F. hepatica antibodies in bulk-tank milk from dairy herds located in East Frisia, a region of the federal state Lower Saxony in the north of Germany, were investigated. This region was chosen since it is known as a high risk area for fluke infections due to its coastal location at the North Sea with the consequence of rather moist pastures. Between 669 and 868 bulk-tank milk samples were collected in January, September and November 2008 and 2010, respectively, and analysed for antibodies against F. hepatica with an in-house ELISA based on excretory-secretory antigens of the liver fluke. The overall East Frisian prevalence was 49.1%, 57.1% and 53.9% in January, September and November 2008 and 45.1%, 49.5% and 48.4% in 2010. From a number of 606 farms, which were sampled in all six investigated months, 34.5% of the farms continued to remain positive, whereas 30.9% continued to remain negative. A percentage of 69.1% (419 farms) were positive on at least one sampling occasion during the study period. The distributions of optical density ratio (ODR) values were skewed to the left but showed a second, lower peak in a high ODR range. Statistical analysis revealed a significant difference concerning the prevalence increase from January to September 2008. Furthermore, the prevalence decrease from September as well as November 2008 to these months in 2010 was significantly different, what might result from a more frequent use of anthelminthics or different climatic conditions.

Schistosoma mansoni: effects of anesthetics and antimonial drugs on worm shift in the mouse

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José Renan da Cunha-Melo

1986-08-01

Full Text Available Mice experimentally infected with Schistosoma mansoni were injected with sodium thiopental or sodium antimonyl gluconate (Triostib R, or submitted to halothane inhalation, with or without a previous injection of thiopental. Data obtained showed that halothane and thiopental induce worm shift to the liver (99 and 76%, respectively. Sodium gluconate and antimonium (Triostib R shifted 52% of worms towards the liver. These results seem to indicate that the use of antimonium would be unnecessary, when surgical removal of schistosomules is carried out through the extracorporeal filtration technique, in patients with portal hypertension.

Prevalence and diversity of fish-borne zoonotic trematodes in tilapia (Oreochromis niloticus) culture in Guangdong, China

DEFF Research Database (Denmark)

Li, Kang; Murrell, Kenneth Darwin; Clausen, Jesper Hedegaard

The fishborne zoonotic trematode parasites (FZT) which cause liver and intestinal infections in humans are widespread in fish in Southeast Asia. Guangdong Province is the most important region for tilapia (Oreochromis niloticus) culture in China, but it is also an endemic region for FZT. To assess...... the potential for FZT transmission in an area with high density of tilapia farms, wild-caught fish from local rivers and canals were bought at local markets. The wild-caught fish species included Hemiculter leucisculus (145), Rhodeus sinensis Gunther (10), Rasborinus lineatus (96), Squaliobarbus curriculus (6......), and Carassius auratus (4).The FZT species recovered were mainly Haplorchis taichui, and H. pumilio along with some unknown species whose identifications are still being determined. Subsequently a cross-sectional survey for the prevalence and diversity of FZT in tilapia culture systems was conducted in Guangdong...

A review on the diagnosis infection in cattle of Schistosoma bovis: current status and future prospects Revisão sobre diagnóstico de infecção por Schistosoma bovis em bovinos: estado atual e perspectivas para o futuro

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Imadeldin Elamin Aradaib

1995-01-01

Full Text Available Bovine schistosomiasis, caused by Schistosoma bovis, is a serious veterinary problem in many parts of the worid. The current methods used for the diagnosis of the disease include clinical signs, pathological lesions, parasitological and serological techniques. As clinical signs and parasitological lesions caused by S. bovis are indistinguishable from those induced by other trematode parasites, confirmation of diagnosis by these methods is unreliable. Parasitological techniques used to demonstrate eggs of the parasite in fecal or tissue samples represent the most accurate method for detection of an active S. bovis infection. The tissue of choice for detection of S. bovis infection is the liver because of the visible macroscopic lesion that can be seen in that organ and the rapid detection of the parasite eggs under the microscope using crush smears. The serological techniques used for diagnosis of the disease do not necessarily identify an active infection. In addition, some of the positive reactions are non specific. However, serology is useful to identify previous infection in epidemiologic study. The ELISA has been recentiy validated for the diagnosis of bovine schistosomiasis and will probably replace the other serological tests. The immunoblotting technique has been proven satisfactory to detect antibodies to defined and recombinant schistosome antigen vaccines. Nucleic acid hybridization techniques have been described for the study of schistosome species-specific identification. However, these molecular techniques have not yet revolutionarized diagnosis of schistosomiasis. These techniques will probably serve as the basis for future diagnostic tests.Esquistossomose bovina, causada pelo parasita Schistosoma bovis, é um problema muito sério para a Veterinária em muitas partes do mundo. Os métodos atuais utilizados para o diagnóstico da doença incluem sinais clínicos, lesões patológicas, e técnicas de parasitologia e sorologia. Como

Influence of the nontarget mollusc Marisa cornuarietis on the hourly cercarial production of Schistosoma mansoni from Biomphalaria glabrata.

Science.gov (United States)

Ferrer, J R; Pointier, J P; Théron, A; Moné, H

1991-10-01

A comparative study of hourly cercarial productivities of Schistosoma mansoni from infected Biomphalaria glabrata was carried out in the presence of either healthy B. glabrata (control) or healthy Marisa cornuarietis (experimental). The results showed that, with M. cornuarietis, almost all the hourly cercarial productivities increased by a factor varying from 1.3 to 2.5 without modification of the shedding period.

The American mink (Neovison vison) is a competent host for native European parasites.

Science.gov (United States)

Martínez-Rondán, F J; Ruiz de Ybáñez, M R; Tizzani, P; López-Beceiro, A M; Fidalgo, L E; Martínez-Carrasco, C

2017-11-30

The American mink (Neovison vison) is a mustelid native to North America that was introduced in Europe and the former USSR for fur farming. Throughout the last century, accidental or deliberate escapes of mink from farms caused the establishment of stable feral populations. In fact, the American mink is considered an invasive alien species in 28 European countries. The present study evaluates the gastrointestinal and cardiopulmonary helminth fauna of the American mink in Galicia (NW Spain) to understand its role as a potential reservoir for parasites affecting other autochthonous mustelids. In the period 2008-2014, fifty American mink (35 males and 15 females) of different ages (22 immature and 28 adults) from the provinces of Lugo, Ourense and Pontevedra were captured and sacrificed. Eight parasite species were found (6 nematodes and 2 trematodes) with the following prevalences: Molineus patens (68%), Aonchotheca putorii (54%), Crenosoma melesi (10%), Aonchotheca annulosa (8%), Angiostrongylus daskalovi (6%), Aelurostrongylus spp. (2%), Troglotrema acutum (2%) and an unidentified trematode (2%). Eighty-two per cent of the mink harboured helminths, including 15 animals (30%) infected by only one parasite species, 19 (38%) by two species, 5 (10%) by three species and 2 mink (4%) by four species. All helminth species identified are native to European mustelids. Statistical models were used to evaluate if animal characteristics (age, sex and weight), date and capture area influenced the prevalence, intensity or parasite richness. Statistical differences were detected only in models for intensity of M. patens, A. putorii and C. melesi. This is the first report of Angiostrongylus daskalovi, a cardiopulmonary nematode, and A. annulosa, a gastrointestinal nematode specific of rodents, in American mink. Moreover, although the fluke T. acutum has already been cited in American mink, to our knowledge, the present study represents the first report of this trematode in the

P53 and cancer-associated sialylated glycans are surrogate markers of cancerization of the bladder associated with Schistosoma haematobium infection.

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Júlio Santos

2014-12-01

Full Text Available Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers.Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67>17%, cell-surface cancer-associated glycan sialyl-Tn (sTn and sialyl-Lewisa/x (sLea/sLex, involved in immune escape and metastasis. Bladder tumours of non-S. haematobium etiology and normal urothelium were used as controls. S. haematobium-associated benign/pre-malignant lesions present alterations in p53 and sLex that were also found in bladder tumors. Similar results were observed in non-S. haematobium associated tumours, irrespectively of their histological nature, denoting some common molecular pathways. In addition, most benign/pre-malignant lesions also expressed sLea. However, proliferative phenotypes were more prevalent in lesions adjacent to bladder tumors while sLea was characteristic of sole benign/pre-malignant lesions, suggesting it may be a biomarker of early carcionogenesis associated with the parasite. A correlation was observed between the frequency of the biomarkers in the tumor and adjacent mucosa, with the exception of Ki-67. Most S. haematobium eggs embedded in the urothelium were also positive for sLea and sLex. Reinforcing the pathologic nature of the studied biomarkers, none was observed in the healthy urothelium

Analysis of the primary structure and post-translational modifications of the Schistosoma mansoni antigen Smp28 by electrospray mass spectrometry

NARCIS (Netherlands)

Bouchon, B.; Jaquinod, M.; Klarskov, K.; Trottein, F.; Klein, Michele; Van Dorsselaer, A.; Bischoff, Rainer; Roitsch, C.

1994-01-01

The Schistosoma mansoni glutathione-S-transferase with an apparent molecular mass of 28 kDa, Smp28, has a blocked N-terminus which has been elucidated with the aid of the cDNA sequence combined with mass spectrometry and amino acid composition analysis of the N-terminal tryptic peptide. The blocked

Estudo quantitativo de metais presentes na hemolinfa de Biomphalaria glabrata (Gastropoda, infectadas e não infectadas com Schistosoma mansoni Quantitative study of metal present in the hemolymph of Biomphalaria glabrata (Gastropoda, infected and uninfected with Schistosoma mansoni

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Marco Antonio Vasconcelos Santos

2005-04-01

Full Text Available Inicialmente, desenvolveu-se um estudo para quantificar e comparar as concentrações de alguns metais presentes em duas amostras de hemolinfa do caramujo Biomphalaria glabrata (infectados e não-infectados com Schistosoma mansoni. A espectrometria de emissão óptica com fonte de plasma induzido (ICP-OES, foi utilizada para analisar os metais nas duas amostras. Os metais estudados foram: alumínio, cálcio, cádmio, cobalto, cromo, cobre, ferro, potássio, magnésio, manganês, chumbo e zinco. Os resultados mostram que, a princípio, os metais não são fatores determinantes no processo de defesa desses organismos contra este parasita, quando presente nos seus tecidos.We conducted a preliminary study to quantify and compare two concentrations of the same metals present in the hemolymph of snail Biomphalaria glabrata. In this context, we used Induction Coupled Plasma Optical Emission Spectroscopy technique (ICP-OES, to analyze the metals in the two samples (snails infected and not infected with Schistosoma mansoni. The metals studied were: aluminum, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, lead and zinc. Preliminary results showed that such metals are not involved in the defense of these organisms against the parasite, when present in their tissues.

Sonographic screening for urinary tract abnormalities in patients with Schistosoma haematobium infection: pitfalls in examining pregnant women.

OpenAIRE

Richter, J.; Wagatsuma, Y.; Aryeetey, M.; Feldmeier, H.

1996-01-01

In areas where Schistosoma haematobium is endemic, urinary schistosomiasis and pregnancy are frequently concomitant; however, both these conditions may produce similar urinary tract changes in ultrasound scans and hence their differential diagnosis may be difficult. In patients with urinary schistosomiasis, focal and/or diffuse urinary bladder wall changes are frequently detected ultrasonically. Dilatation of one or both ureters and progressive hydronephrosis may be observed in more severe ca...

Schistosoma mansoni: host cell adhesion to the different stages of the parasite, in vivo Schistosoma mansoni: adesão de células do hospedeiro aos diferentes estádios do parasito, in vivo

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Alan L. Melo

1992-06-01

Full Text Available The peritoneal cavity of laboratory mice was used to study the phenomenon of host cell adhesion to different evolutive stages of the Schistosoma mansoni (cercaria, adult worm, developing and mature eggs, miracidium, young and mature daughter sporocysts. Material recovered from the peritoneal cavity 30 and 180 min after the inoculation of each evolutive form was examined with the help of a stereomicroscope. The free swimming larvae (cercaria and miracidium, and the evolutive forms producing such larvae (mature egg and mature daughter sporocyst elicited the host cell adhesion phenomenon. In all forms but cercariae the adherent cells remained as so till 180 minutes after inoculationA cavidade peritoneal de camundongos foi utilizada para estudos de adesão celular a diferentes estádios evolutivos do Schistosoma mansoni (cercária, verme adulto, ovos imaturos e maduros, miracídio, esporocisto jovem e esporocisto maduro. O material recuperado da cavidade peritoneal 30 e 180 min após o inóculo, foi examinado com auxílio de estereomicroscópio. As formas livres (cercária e miracídio e as formas evolutivas que produzem tais larvas (ovo maduro e esporocisto maduro apresentam células do hospedeiro aderidas à superfície. Em todas as formas, exceto cercária, as células permanecem aderidas pelo menos até 180 min após o inóculo

Do parasitic trematode cercariae demonstrate a preference for susceptible host species?

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Brittany F Sears

Full Text Available Many parasites are motile and exhibit behavioural preferences for certain host species. Because hosts can vary in their susceptibility to infections, parasites might benefit from preferentially detecting and infecting the most susceptible host, but this mechanistic hypothesis for host-choice has rarely been tested. We evaluated whether cercariae (larval trematode parasites prefer the most susceptible host species by simultaneously presenting cercariae with four species of tadpole hosts. Cercariae consistently preferred hosts in the following order: Anaxyrus ( = Bufo terrestris (southern toad, Hyla squirella (squirrel tree frog, Lithobates ( = Rana sphenocephala (southern leopard frog, and Osteopilus septentrionalis (Cuban tree frog. These host species varied in susceptibility to cercariae in an order similar to their attractiveness with a correlation that approached significance. Host attractiveness to parasites also varied consistently and significantly among individuals within a host species. If heritable, this individual-level host variation would represent the raw material upon which selection could act, which could promote a Red Queen "arms race" between host cues and parasite detection of those cues. If, in general, motile parasites prefer to infect the most susceptible host species, this phenomenon could explain aggregated distributions of parasites among hosts and contribute to parasite transmission rates and the evolution of virulence. Parasite preferences for hosts belie the common assumption of disease models that parasites seek and infect hosts at random.

Analysis of recombinant Schistosoma mansoni antigen rSmp28 by on-line liquid chromatography-mass spectrometry combined with sodium dodecyl sulfate polyacrylamide gel electrophoresis

NARCIS (Netherlands)

Klarskov, K.; Roecklin, D.; Bouchon, B.; Sabatie, J.; Van Dorsselaer, A.; Bischoff, Rainer

1994-01-01

A recombinant Schistosoma mansoni antigen produced in Saccharomyces cerevisiae and purified by glutathione-Sepharose affinity chromatography was analyzed by tryptic peptide mapping using on-line reversed-phase high-performance liquid chromatography pneumatically assisted electrospray mass

Modelling climate change impact on the spatial distribution of fresh water snails hosting trematodes in Zimbabwe.

Science.gov (United States)

Pedersen, Ulrik B; Stendel, Martin; Midzi, Nicholas; Mduluza, Takafira; Soko, White; Stensgaard, Anna-Sofie; Vennervald, Birgitte J; Mukaratirwa, Samson; Kristensen, Thomas K

2014-12-12

Freshwater snails are intermediate hosts for a number of trematodes of which some are of medical and veterinary importance. The trematodes rely on specific species of snails to complete their life cycle; hence the ecology of the snails is a key element in transmission of the parasites. More than 200 million people are infected with schistosomes of which 95% live in sub-Saharan Africa and many more are living in areas where transmission is on-going. Human infection with the Fasciola parasite, usually considered more of veterinary concern, has recently been recognised as a human health problem. Many countries have implemented health programmes to reduce morbidity and prevalence of schistosomiasis, and control programmes to mitigate food-borne fascioliasis. As these programmes are resource demanding, baseline information on disease prevalence and distribution becomes of great importance. Such information can be made available and put into practice through maps depicting spatial distribution of the intermediate snail hosts. A biology driven model for the freshwater snails Bulinus globosus, Biomphalaria pfeifferi and Lymnaea natalensis was used to make predictions of snail habitat suitability by including potential underlying environmental and climatic drivers. The snail observation data originated from a nationwide survey in Zimbabwe and the prediction model was parameterised with a high resolution Regional Climate Model. Georeferenced prevalence data on urinary and intestinal schistosomiasis and fascioliasis was used to calibrate the snail habitat suitability predictions to produce binary maps of snail presence and absence. Predicted snail habitat suitability across Zimbabwe, as well as the spatial distribution of snails, is reported for three time slices representative for present (1980-1999) and future climate (2046-2065 and 2080-2099). It is shown from the current study that snail habitat suitability is highly variable in Zimbabwe, with distinct high- and low

Long-term frozen storage of urine samples: a trouble to get PCR results in Schistosoma spp. DNA detection?

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Pedro Fernández-Soto

Full Text Available BACKGROUND: Human schistosomiasis remains a serious worldwide public health problem. At present, a sensitive and specific assay for routine diagnosis of schistosome infection is not yet available. The potential for detecting schistosome-derived DNA by PCR-based methods in human clinical samples is currently being investigated as a diagnostic tool with potential application in routine schistosomiasis diagnosis. Collection of diagnostic samples such as stool or blood is usually difficult in some populations. However, urine is a biological sample that can be collected in a non-invasive method, easy to get from people of all ages and easy in management, but as a sample for PCR diagnosis is still not widely used. This could be due to the high variability in the reported efficiency of detection as a result of the high variation in urine samples' storage or conditions for handling and DNA preservation and extraction methods. METHODOLOGY/PRINCIPAL FINDINGS: We evaluate different commercial DNA extraction methods from a series of long-term frozen storage human urine samples from patients with parasitological confirmed schistosomiasis in order to assess the PCR effectiveness for Schistosoma spp. detection. Patients urine samples were frozen for 18 months up to 7 years until use. Results were compared with those obtained in PCR assays using fresh healthy human urine artificially contaminated with Schistosoma mansoni DNA and urine samples from mice experimentally infected with S. mansoni cercariae stored frozen for at least 12 months before use. PCR results in fresh human artificial urine samples using different DNA based extraction methods were much more effective than those obtained when long-term frozen human urine samples were used as the source of DNA template. CONCLUSIONS/SIGNIFICANCE: Long-term frozen human urine samples are probably not a good source for DNA extraction for use as a template in PCR detection of Schistosoma spp., regardless of the DNA

Development of a Schistosoma mansoni shotgun O-glycan microarray and application to the discovery of new antigenic schistosome glycan motifs.

Science.gov (United States)

van Diepen, Angela; van der Plas, Arend-Jan; Kozak, Radoslaw P; Royle, Louise; Dunne, David W; Hokke, Cornelis H

2015-06-01

Upon infection with Schistosoma, antibody responses are mounted that are largely directed against glycans. Over the last few years significant progress has been made in characterising the antigenic properties of N-glycans of Schistosoma mansoni. Despite also being abundantly expressed by schistosomes, much less is understood about O-glycans and antibody responses to these have not yet been systematically analysed. Antibody binding to schistosome glycans can be analysed efficiently and quantitatively using glycan microarrays, but O-glycan array construction and exploration is lagging behind because no universal O-glycanase is available, and release of O-glycans has been dependent on chemical methods. Recently, a modified hydrazinolysis method has been developed that allows the release of O-glycans with free reducing termini and limited degradation, and we applied this method to obtain O-glycans from different S. mansoni life stages. Two-dimensional HPLC separation of 2-aminobenzoic acid-labelled O-glycans generated 362 O-glycan-containing fractions that were printed on an epoxide-modified glass slide, thereby generating the first shotgun O-glycan microarray containing naturally occurring schistosome O-glycans. Monoclonal antibodies and mass spectrometry showed that the O-glycan microarray contains well-known antigenic glycan motifs as well as numerous other, potentially novel, antibody targets. Incubations of the microarrays with sera from Schistosoma-infected humans showed substantial antibody responses to O-glycans in addition to those observed to the previously investigated N- and glycosphingolipid glycans. This underlines the importance of the inclusion of these often schistosome-specific O-glycans in glycan antigen studies and indicates that O-glycans contain novel antigenic motifs that have potential for use in diagnostic methods and studies aiming at the discovery of vaccine targets. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights

Avaliação terapêutica do artesunato na infecção experimental pelo Schistosoma mansoni Therapeutical evaluation of the artesunate in experimental Schistosoma mansoni infection

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Neusa Araújo

1999-02-01

Full Text Available Camundongos infectados experimentalmente com Schistosoma mansoni foram tratados, em dose oral única, com artesunato (LACTAB®, 300 ou 500mg/kg ou durante cinco dias consecutivos. Os animais foram sacrificados 7, 30, 60 ou 90 dias após o tratamento. Diferenças estatisticamente significativas foram encontradas na distribuição e mortalidade dos vermes e na alteração do oograma nos grupos tratados quando comparados ao controle, em todos os esquemas testados quando os animais foram sacrificados 30 dias após o tratamento. A análise morfológica dos vermes mostrou alterações no aparelho reprodutor feminino com diminuição do volume ovariano, rarefação dos folículos vitelínicos, alterações estas mais acentuadas nas dosagens mais altas, justificando o encontro na alteração do oograma que chegou a 100%. Entretanto, quando os animais foram sacrificados 60 ou 90 dias após o tratamento, as diferenças e alterações foram menores, mostrando que os vermes sobreviventes se recuperaram e reiniciaram a postura.Mice experimentally infected with Schistosoma mansoni were treated orally with artesunate (Lactab® in a single dose of 300 or 500mg/kg or over a period of five consecutive days. The animals were sacrificed 7, 30, 60 or 90 days after treatment. Statistically significant differences were found in the distribution and mortality of the worms and in the alterations of the oogram in the treated group when compared to control in all of the tested schemes when the animals were sacrificed 30 days after treatment. Morphological analysis of female worms showed a reduction of ovarian volume and rarefaction of the vitelline follicles. These modifications were more marked after treatment with the higher dose, explaining the alteration of the oogram which reached 100%. However, when the animals were sacrificed 60 or 90 days after treatment, the differences and alterations were smaller, showing that the surviving worms recovered and restarted

Identification and characterization of novel microRNAs from Schistosoma japonicum.

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Xiangyang Xue

Full Text Available BACKGROUND: Schistosomiasis japonica remains a major public health problem in China. Its pathogen, Schistosoma japonicum has a complex life cycle and a unique repertoire of genes expressed at different life cycle stages. Exploring schistosome gene regulation will yield the best prospects for new drug targets and vaccine candidates. MicroRNAs (miRNAs are a highly conserved class of noncoding RNA that control many biological processes by sequence-specific inhibition of gene expression. Although a large number of miRNAs have been identified from plants to mammals, it remains no experimental proof whether schistosome exist miRNAs. METHODOLOGY AND RESULTS: We have identified novel miRNAs from Schistosoma japonicum by cloning and sequencing a small (18-26 nt RNA cDNA library from the adult worms. Five novel miRNAs were identified from 227 cloned RNA sequences and verified by Northern blot. Alignments of the miRNAs with corresponding family members indicated that four of them belong to a metazoan miRNA family: let-7, miR-71, bantam and miR-125. The fifth potentially new (non conserved miRNA appears to belong to a previously undescribed family in the genus Schistosome. The novel miRNAs were designated as sja-let-7, sja-miR-71, sja-bantam, sja-miR-125 and sja-miR-new1, respectively. Expression of sja-let-7, sja-miR-71 and sja-bantam were analyzed in six stages of the life cycle, i.e. egg, miracidium, sporocyst, cercaria, schistosomulum, and adult worm, by a modified stem-loop reverse transcribed polymerase chain reaction (RT-PCR method developed in our laboratory. The expression patterns of these miRNAs were highly stage-specific. In particular, sja-miR-71 and sja-bantam expression reach their peaks in the cercaria stage and then drop quickly to the nadirs in the schistosomulum stage, following penetration of cercaria into a mammalian host. CONCLUSIONS: Authentic miRNAs were identified for the first time in S. japonicum, including a new schistosome

Biology and Control of Snail Intermediate Host of Schistosoma japonicum in The People's Republic of China

DEFF Research Database (Denmark)

Li, Z.J.; Ge, J; Dai, J.R.

2016-01-01

Schistosomiasis caused by Schistosoma japonicum is a severe parasitic disease in The People's Republic of China and imposed considerable burden on human and domestic animal health and socioeconomic development. The significant achievement in schistosomiasis control has been made in last 60years. ....... Oncomelania hupensis as the only intermediate host of S. japonicum plays a key role in disease transmission. The habitat complexity of the snails challenges to effective control. In this review we share the experiences in control and research of O. hupensis....

Estudo morfológico do Schistosoma mansoni Sambon, 1907 encontrado na espécie humana

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M. R. Q. de Kastner

1975-10-01

Full Text Available O presente trabalho estuda; a morfologia do Schistosoma mansoni Sambon, 1907, obtido por filtração extra-corpórea de 5 (cinco pacientes do Hospital São Vicente de Paula em Minas Gerais. Foram elucidados detalhes morfológicos até então controvertidos na literatura, tendo sido, inclusive, correlacionados com os estudados pela microscopia eletrônica por outros autores. Não foram observadas diferenças morfológicas entre os vermes humanos e os descritos em animais de pequeno porte.

Cerebral vasculitis associated with Schistosoma mansoni infection

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Camuset Guillaume

2012-09-01

Full Text Available Abstract Background Cerebral involvement in schistosomiasis is not rare, but it is underdiagnosed because of the lack of clinical suspicion and the frequency of asymptomatic forms. Neurologic complications are generally supported by granuloma formation around ectopic eggs which have migrated to the brain. Moreover, vascular lesions and cerebral arteritis have been well documented in histopathological studies. Nevertheless, cerebral vasculitis in later stages of the Schistosoma mansoni infection have not yet been described in living subjects. Case presentation A 28-year-old french woman had a stroke linked with cerebral vasculitis, 6 monthes after returning from Burkina-Faso. At the same time, a S. mansoni disseminated infection was diagnosed. She suffered from a new stroke after undertaking praziquantel therapy, which lead us to associate the S. mansoni infection and cerebral vasculitis. Conclusion This is the first report of such association, since cerebral vasculitis has never been described in later stages of the S. mansoni infection. Although the causal link between the two pathologies could not be proved, we suggest that S. mansoni is able to cause severe vascular damage in cerebral vessels. Schistosomiasis must be investigated in the event of a brain infarct in young people, particularly in patients originating or returning from an endemic area.

Synthesis and conjugation of oligosaccharide fragments related to the immunologically reactive part of the circulating anodic antigen of the parasite Schistosoma mansoni

NARCIS (Netherlands)

Vliegenthart, J.F.G.; Vermeer, H.J.; Halkes, K.M.; Kuik, J.A. van; Kamerling, J.P.

2000-01-01

The immunoreactive part of the circulating anodic antigen (CAA) from the parasite Schistosoma mansoni is a threonine-linked polysaccharide consisting of ->6)-[beta-D-GlcpA-(1->3)]-beta-D-GalpNAc-(1-> repeating disaccharides. In the framework of an immunochemical project, as a follow-up of earlier

Mercury in parasitic nematodes and trematodes and their double-crested cormorant hosts: Bioaccumulation in the face of sequestration by nematodes

International Nuclear Information System (INIS)

Robinson, Stacey A.; Forbes, Mark R.; Hebert, Craig E.

2010-01-01

Endoparasites can alter their host's heavy metal concentrations by sequestering metals in their own tissues. Contracaecum spp. (a nematode), but not Drepanocephalus spathans (a trematode), were bioaccumulating mercury to concentrations 1.5 times above cormorant hosts. Nematodes did not have significantly greater stable nitrogen isotope values (δ 15 N) than their hosts, which is contradictory to prey-predator trophic enrichment studies, but is in agreement with other endoparasite-host relationships. However, Contracaecum spp. δ 13 C values were significantly greater than their hosts, which suggest that nematodes were consuming host tissues. Nematodes were accumulating and thus sequestering some of their cormorant hosts' body burden of methyl mercury; however, they were not dramatically reducing their hosts' accumulation of methyl mercury.

Application of Pineapple Juice in the Fish Digestion Process for Carcinogenic Liver Fluke Metacercaria Collection

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Sripan, Panupan; Aukkanimart, Ratchadawan; Boonmars, Thidarut; Pranee, Sriraj; Songsri, Jiraporn; Boueroy, Parichart; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara

2017-01-01

Pepsin is common digestive enzyme used for fish digestion in the laboratory to collect trematode metacercariae. In a field study, to survey the infected fish is needed a huge yield of pepsin and it is very expensive. Therefore, our purpose of this study was to investigate the candidate enzyme from pineapple juice which has a digestive enzyme called bromelain, a mixture of proteolytic enzymes, to digest fish in order to harvest metacercariae. Fish were divided into 2 groups: one group in which metacercariae were harvested using acid pepsin as a control and other groups in which the fish was digested using fresh pineapple juices. The results showed that pineapple juice is able to digest fish similarly to pepsin. The Pattavia pineapple juice had the highest number of metacercariae similar to the control. For Trat Si Thong pineapple juice, we found the number of metacercariae was less than control. This result suggests that the Pattavia pineapple juice was optimal juice for fish digestion to metacercaria collection and can be used instread of pepsin acid. PMID:28441786

Point-of-care mobile digital microscopy and deep learning for the detection of soil-transmitted helminths and Schistosoma haematobium.

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Holmström, Oscar; Linder, Nina; Ngasala, Billy; Mårtensson, Andreas; Linder, Ewert; Lundin, Mikael; Moilanen, Hannu; Suutala, Antti; Diwan, Vinod; Lundin, Johan

2017-06-01

Microscopy remains the gold standard in the diagnosis of neglected tropical diseases. As resource limited, rural areas often lack laboratory equipment and trained personnel, new diagnostic techniques are needed. Low-cost, point-of-care imaging devices show potential in the diagnosis of these diseases. Novel, digital image analysis algorithms can be utilized to automate sample analysis. Evaluation of the imaging performance of a miniature digital microscopy scanner for the diagnosis of soil-transmitted helminths and Schistosoma haematobium, and training of a deep learning-based image analysis algorithm for automated detection of soil-transmitted helminths in the captured images. A total of 13 iodine-stained stool samples containing Ascaris lumbricoides, Trichuris trichiura and hookworm eggs and 4 urine samples containing Schistosoma haematobium were digitized using a reference whole slide-scanner and the mobile microscopy scanner. Parasites in the images were identified by visual examination and by analysis with a deep learning-based image analysis algorithm in the stool samples. Results were compared between the digital and visual analysis of the images showing helminth eggs. Parasite identification by visual analysis of digital slides captured with the mobile microscope was feasible for all analyzed parasites. Although the spatial resolution of the reference slide-scanner is higher, the resolution of the mobile microscope is sufficient for reliable identification and classification of all parasites studied. Digital image analysis of stool sample images captured with the mobile microscope showed high sensitivity for detection of all helminths studied (range of sensitivity = 83.3-100%) in the test set (n = 217) of manually labeled helminth eggs. In this proof-of-concept study, the imaging performance of a mobile, digital microscope was sufficient for visual detection of soil-transmitted helminths and Schistosoma haematobium. Furthermore, we show that deep

Apoptosis Governs the Elimination of Schistosoma japonicum from the Non-Permissive Host Microtus fortis

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Peng, Jinbiao; Gobert, Geoffrey N.; Hong, Yang; Jiang, Weibin; Han, Hongxiao; McManus, Donald P.; Wang, Xinzhi; Liu, Jinming; Fu, Zhiqiang; Shi, Yaojun; Lin, Jiaojiao

2011-01-01

The reed vole, Microtus fortis, is the only known mammalian host in which schistosomes of Schistosoma japonicum are unable to mature and cause significant pathogenesis. However, little is known about how Schistosoma japonicum maturation (and, therefore, the development of schistosomiasis) is prevented in M. fortis. In the present study, the ultrastructure of 10 days post infection schistosomula from BALB/c mice and M. fortis were first compared using scanning electron microscopy and transmission electron microscopy. Electron microscopic investigations showed growth retardation and ultrastructural differences in the tegument and sub-tegumental tissues as well as in the parenchymal cells of schistosomula from M. fortis compared with those in BALB/c mice. Then, microarray analysis revealed significant differential expression between the schistosomula from the two rodents, with 3,293 down-regulated (by ≥2-fold) and 71 up-regulated (≥2 fold) genes in schistosomula from the former. The up-regulated genes included a proliferation-related gene encoding granulin (Grn) and tropomyosin. Genes that were down-regulated in schistosomula from M. fortis included apoptosis-inhibited genes encoding a baculoviral IAP repeat-containing protein (SjIAP) and cytokine-induced apoptosis inhibitor (SjCIAP), genes encoding molecules involved in insulin metabolism, long-chain fatty acid metabolism, signal transduction, the transforming growth factor (TGF) pathway, the Wnt pathway and in development. TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) and PI/Annexin V-FITC assays, caspase 3/7 activity analysis, and flow cytometry revealed that the percentages of early apoptotic and late apoptotic and/or necrotic cells, as well as the level of caspase activity, in schistosomula from M. fortis were all significantly higher than in those from BALB/c mice. PMID:21731652

Therapeutic effect of Arctium lappa in Schistosoma haematobium associated kidney disturbance: biochemical and molecular effects.

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Koriem, Khaled M M; Idris, Zulzamri H; Haron, Hasniza F; Omar, Nurulhuda A; Lazain, Halita S

2016-12-01

Schistosoma haematobium ( S. haematobium ) infection has been found to be strongly associated with bladder cancer, which necessitates for discover of a natural new therapeutic agent. The aim of this study was to evaluate the therapeutic effect of Arctium lappa seed extract in S. haematobium associated kidney disturbance. Forty male albino mice were used and divided into four equal groups; group 1 control includes non-infected healthy mice, groups 2, 3 and 4 subcutaneous infected with S. haematobium cercariae. Groups 3 co-treated daily with oral dose of A. lappa seed extract (300 mg/kg, bwt) for 15 days in the same time of S. haematobium infection. Groups 4 post-treated daily for 15 days with oral dose of A. lappa seed extract (300 mg/kg, bwt) after 15 days of S. haematobium infection. The results obtained revealed that S. haematobium significantly decreased kidney weight and serum sodium, potassium and chloride, but increased urinary volume, urinary excretion of sodium, potassium and chloride, serum urea, creatinine and uric acid. Schistosoma haematobium also significantly decreased kidney superoxide dismutase, glutathione peroxidase and reduced glutathione levels while increased kidney lipid peroxidation level. Co- and post-treatment with A. lappa seed extract restore all the above parameters to approach the normal values. These results were supported with histopathological examinations. In conclusion, A. lappa seed extract has therapeutic effect in kidney disturbance caused by S. haematobium where co-treatment of A. lappa seed extract was more effective than post-treatment of the extract.

Inheritance of Schistosoma mansoni infection incompatibility in Biomphalaria alexandrina snails

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Iman F Abou El Naga

2010-03-01

Full Text Available In this study, we looked at the inheritance of susceptibility and resistance to Schistosoma mansoni infection in the first generation of crossbred Biomphalaria alexandrina snails. Our ultimate goal is to use such information to develop a biological method of controlling schistosomiasis. We infected laboratory-bred snails with S. mansoni miracidia and examined cercarial shedding to determine susceptibility and resistance. Five parental groups were used: Group I contained 30 susceptible snails, Group II contained 30 resistant snails, Group III contained 15 susceptible and 15 resistant snails, Group IV contained 27 susceptible and three resistant snails and Group V contained three susceptible and 27 resistant snails. The percentage of resistant snails in the resulting progeny varied according to the ratio of susceptible and resistant parents per group; they are 7%, 100%, 68%, 45% and 97% from Groups I, II, III, IV and V, respectively. On increasing the percentage of resistant parent snails, the percentage of resistant progeny increased, while cercarial production in their susceptible progeny decreased.

Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds.

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Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

2015-09-01

The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (phepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Bulk milk-estimated seroprevalence of Fasciola hepatica in dairy herds and collecting of risk factor data in East Frisia, northern Germany.

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Kuerpick, Birte; Fiedor, Christiane; von Samson-Himmelstjerna, Georg; Schnieder, Thomas; Strube, Christina

2012-01-01

The liver fluke Fasciola (F) hepatica is one of the most important trematodes in cattle farming worldwide. Fasciolosis in dairy cows is leading to production losses due to decreased milk yield, liver condemnation and impaired reproduction. The treatment of dairy cows is unsatisfactory, because available drugs are either effective against adult flukes only or have long withdrawal times or in some countries may not be used at all. In the present study the prevalence of F. hepatica in dairy farms located in East Frisia, which is part of the federal state Lower Saxony, was investigated. East Frisia is considered a high risk area for Fasciola hepatica infections, because of its coastal location, high precipitation and moist pastures. About 750 bulk milk samples were collected in January and November 2006 and analysed for F. hepatica antibodies using the Pourquier ELISA. In addition, questionnaires, which were answered by 260 of the participating farmers, were evaluated to analyse management-related factors associated with fasciolosis. In January and November, 52.1% and 53.6% of the bulk milk samples, respectively, showed positive results. Thereby, 88.1% of the examined farms showed an unchanged infection status, whereas 6.2% of the farms became seropositive during the grazing season and 5.8% of the dairy herds turned seronegative. Statistical analysis revealed a significant negative association between average annual milk production and the frequency of infections with F. hepatica.

Studies on some fish parasites of public health importance in the southern area of Saudi Arabia

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Mokhtar Ibrahim Khalil

2014-12-01

Full Text Available The present study was the first attempt to survey the diversity of fish zoonotic parasites in the southern region of Saudi Arabia, particularly the Najran area, from October 2012 to October 2013. Approximately 163 fish representing seven species (two of freshwater fish and five of marine fish were examined for fish-borne trematode metacercariae using the compression technique, and for zoonotic nematode larvae. Adult flukes were obtained from cats experimentally infected with the metacercariae on day 25 post-infection The prevalence of each parasite species was recorded. The parasites found belonged to two taxa: Digenea (Heterophyes heterophyes and Haplorchis pumilio in muscle tissue; and nematodes (larvae of Capillaria sp. in the digestive tract. The morphological characteristics of the fish-borne trematode metacercariae and their experimentally obtained adults were described. This is the first report of these parasites in fish in Saudi Arabia. Moreover, Myripristis murdjan presented higher prevalence of Capillaria sp. infection (22.7%, while Haplorchis pumilio was the dominant metacercarial species (7.9%. Although the number of documented cases continues to increase, the overall risk of human infection is slight. The increasing exploitation of the marine environment by humans and the tendency to reduce cooking times when preparing seafood products both increase the chances of becoming infected with these parasites. Furthermore, our results indicate that certain fish production systems are at risk of presenting fish zoonotic parasites, and that control approaches will benefit from understanding these risk factors.

Studies on some fish parasites of public health importance in the southern area of Saudi Arabia.

Science.gov (United States)

Khalil, Mokhtar Ibrahim; El-Shahawy, Ismail Saad; Abdelkader, Hussein Saad

2014-01-01

The present study was the first attempt to survey the diversity of fish zoonotic parasites in the southern region of Saudi Arabia, particularly the Najran area, from October 2012 to October 2013. Approximately 163 fish representing seven species (two of freshwater fish and five of marine fish) were examined for fish-borne trematode metacercariae using the compression technique, and for zoonotic nematode larvae. Adult flukes were obtained from cats experimentally infected with the metacercariae on day 25 post-infection The prevalence of each parasite species was recorded. The parasites found belonged to two taxa: Digenea (Heterophyes heterophyes and Haplorchis pumilio) in muscle tissue; and nematodes (larvae of Capillaria sp.) in the digestive tract. The morphological characteristics of the fish-borne trematode metacercariae and their experimentally obtained adults were described. This is the first report of these parasites in fish in Saudi Arabia. Moreover, Myripristis murdjan presented higher prevalence of Capillaria sp. infection (22.7%), while Haplorchis pumilio was the dominant metacercarial species (7.9%). Although the number of documented cases continues to increase, the overall risk of human infection is slight. The increasing exploitation of the marine environment by humans and the tendency to reduce cooking times when preparing seafood products both increase the chances of becoming infected with these parasites. Furthermore, our results indicate that certain fish production systems are at risk of presenting fish zoonotic parasites, and that control approaches will benefit from understanding these risk factors.

The effect of colostrum on pigs pre-natally or post-natally exposed to Schistosoma japonicum

DEFF Research Database (Denmark)

Techau, M.E.; Johansen, M.V.; Lind, Peter

2004-01-01

Pre-natal infection of Schistosoma japonicum in pigs may prove to be a useful model in shedding light on human pre-natal schistosomiasis. This study describes the effects of immune colostrum on worm burdens, tissue egg counts, liver pathology and crude worm or egg antigen-specific IgG and Ig......A responses, in groups of pigs pre-natally, pre-natally + post-natally or post-natally exposed to S. japonicum. Results suggest that pre-natal exposure and immune colostrum did not affect the establishment of a post-natal challenge infection. However, immune colostrum seemed to increase the levels of septal...

Small-sized euryhaline fish as intermediate hosts of the digenetic trematode Cryptocotyle concavum

Science.gov (United States)

Zander, C. D.; Kollra, H.-G.; Antholz, B.; Meyer, W.; Westphal, D.

1984-03-01

Cercariae of the trematode Cryptocotyle concavum, which encyst in skin and/or kidney of sticklebacks and gobies, were studied in the Schlei Fjord (western Baltic Sea). Mean incidence of dermal cysts was 48 % in Gasterosteus aculeatus and 37 % in Pungitius pungitius. No cysts were found in the kidneys of sticklebacks. While 97 % of Pomatoschistus microps had encysted metacercariae in the kidneys, only 2 % had cysts in the skin. Pomatoschistus minutus, however, showed hardly any cyst infestation of either skin or kidney. In P. microps the intensity of infestation by metacercariae was frequently more than 50 cysts; in contrast, sticklebacks rarely exhibited more than 5 dermal cysts. Infested fish were larger than 10 mm in total length, the incidence rate increasing with growth. Parasitic infestation depends on ambient salinity: C. concavum was not found at salinities below 4 ‰. In contrast to the high incidence in fish, the first hosts — the snails Hydrobia stagnalis and H. neglecta — showed remarkably low infection rates (3 to 5 %). The findings reported are related to the distribution of C. concavum, the mode of life of infested fish, the feeding habits of the final hosts and the infestation of P. microps by other parasites. Evidently, P. microps represents an optimal second host for C. concavum.

Bulinus nyassanus is an intermediate host for Schistosoma haematobium in Lake Malawi

DEFF Research Database (Denmark)

Madsen, H.; Bloch, P.; Phiri, H.

2001-01-01

At Cape Maclear on the Nankumba Peninsula, close to the southern end of Lake Malawi, Schistosoma haematobium is highly prevalent in the local people and many tourists become infected with this parasite each year. A 'Bilharzia Control Programme' was initiated in this area in August 1998......, field-collected B. nyassanus. These are remarkable observations since, although there are very few reports of diploid members of this species group being experimentally infected with S. haematobium, B. nyassanus is a diploid member (2n = 36) of the truncatus/tropicus group. Bulinus nyassanus is probably......, schistosome-infected B. nyassanus were discovered in surveys to identify transmission sites on the peninsula. Experimental infections of wild-caught B. nyassanus with S. haematobium proved successful and S. haematobium eggs were found in hamsters experimentally exposed to cercariae retrieved from schistosome-infected...

Mercury in parasitic nematodes and trematodes and their double-crested cormorant hosts: Bioaccumulation in the face of sequestration by nematodes

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Robinson, Stacey A., E-mail: srobinsc@connect.carleton.ca [Department of Biology, Carleton University, 209 Nesbitt Bldg, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6 (Canada); Forbes, Mark R., E-mail: mforbes6@gmail.com [Department of Biology, Carleton University, 209 Nesbitt Bldg, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6 (Canada); Hebert, Craig E., E-mail: Craig.Hebert@ec.gc.ca [Environment Canada, National Wildlife Research Centre, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1A 0H3 (Canada)

2010-10-15

Endoparasites can alter their host's heavy metal concentrations by sequestering metals in their own tissues. Contracaecum spp. (a nematode), but not Drepanocephalus spathans (a trematode), were bioaccumulating mercury to concentrations 1.5 times above cormorant hosts. Nematodes did not have significantly greater stable nitrogen isotope values ({delta}{sup 15}N) than their hosts, which is contradictory to prey-predator trophic enrichment studies, but is in agreement with other endoparasite-host relationships. However, Contracaecum spp. {delta}{sup 13}C values were significantly greater than their hosts, which suggest that nematodes were consuming host tissues. Nematodes were accumulating and thus sequestering some of their cormorant hosts' body burden of methyl mercury; however, they were not dramatically reducing their hosts' accumulation of methyl mercury.

Micro-geographical heterogeneity in Schistosoma mansoni and S. haematobium infection and morbidity in a co-endemic community in northern Senegal.

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Lynn Meurs

Full Text Available BACKGROUND: Schistosoma mansoni and S. haematobium are co-endemic in many areas in Africa. Yet, little is known about the micro-geographical distribution of these two infections or associated disease within such foci. Such knowledge could give important insights into the drivers of infection and disease and as such better tailor schistosomiasis control and elimination efforts. METHODOLOGY: In a co-endemic farming community in northern Senegal (346 children (0-19 y and 253 adults (20-85 y; n = 599 in total, we studied the spatial distribution of S. mansoni and S. haematobium single and mixed infections (by microscopy, S. mansoni-specific hepatic fibrosis, S. haematobium-specific urinary tract morbidity (by ultrasound and water contact behavior (by questionnaire. The Kulldorff's scan statistic was used to detect spatial clusters of infection and morbidity, adjusted for the spatial distribution of gender and age. PRINCIPAL FINDINGS: Schistosoma mansoni and S. haematobium infection densities clustered in different sections of the community (p = 0.002 and p = 0.023, respectively, possibly related to heterogeneities in the use of different water contact sites. While the distribution of urinary tract morbidity was homogeneous, a strong geospatial cluster was found for severe hepatic fibrosis (p = 0.001. Particularly those people living adjacent to the most frequently used water contact site were more at risk for more advanced morbidity (RR = 6.3; p = 0.043. CONCLUSIONS/SIGNIFICANCE: Schistosoma infection and associated disease showed important micro-geographical heterogeneities with divergent patterns for S. mansoni and S. haematobium in this Senegalese community. Further in depth investigations are needed to confirm and explain our observations. The present study indicates that local geospatial patterns should be taken into account in both research and control of schistosomiasis. The observed extreme focality of schistosomiasis even at community level

Helminthic infections mimicking malignancy: a review of published case reports.

Science.gov (United States)

Pilsczek, Florian H

2010-08-04

Infectious diseases, including infections with helminths, can initially present similarly to malignancies. The goal of the article is to review reports of helminthic infections that are initially diagnosed as malignancy. The database PubMed was searched for English language references published as of July 2009. The following published case reports and case series, mainly from Asia and Africa, were identified: Nematodes: 8 publications (1 patient with Angiostrongylus cantonensis, 2 Stronglyloides stercoralis, 1 Toxocara species, 1 Dioctophyma renale, 1 Ascaris species, 1 Gnathostoma spinigerum, 1 Dirofilaria repens); Trematodes: 7 publications (46 patients with Schistosoma species, 2 Fasciola hepatica, 1 Paragonimus westermani); Cestodes: 6 publications (10 patients with Echinococcus species, 1 Sparganum mansoni). To avoid unnecessary investigations and treatment, physicians should be aware when diagnosing patients from Asia or Africa that a large number of helminthic infections can present similar to malignancies.

Protection of sheep against Schistosoma bovis using cryopreserved radiation-attenuated schistosomula

International Nuclear Information System (INIS)

James, E.R.; Dobinson, A.R.; Andrews, B.J.; Bickle, Q.D.; Taylor, M.G.; Ham, P.J.

1985-01-01

Three sheep were vaccinated with two doses of 3 krad-irradiated cryopreserved Schistosoma bovis schistosomula containing 20,000 and 17,000 organisms respectively, injected intramuscularly 23 days apart after storage in liquid nitrogen for between 9 and 46 days. A challenge of 5360 S. bovis cercariae was administered percutaneously approximately four weeks after the last vaccine dose to these animals and to three controls. Post-challenge the vaccinated animals gained significantly more weight (27% v. 9%), produced fewer eggs in their faeces, showed a smaller reduction in PCV values (-18% v. -27%) and were over-all in better condition than control animals. At perfusion 49.1% fewer adult worms were found in the vaccinated sheep than in controls. The tissue egg burdens were similar in both groups. Histopathologically both groups were similar except that fewer and smaller egg lesions were observed in the livers of vaccinated animals. (author)

Prevalence of Schistosoma mansoni Infection in Four Health Areas of Kisantu Health Zone, Democratic Republic of the Congo

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R. Khonde Kumbu

2016-01-01

Full Text Available Background. Schistosomiasis is a public health problem in Democratic Republic of the Congo but estimates of its prevalence vary widely. The aim of this study was to determine prevalence of Schistosoma mansoni infection and associated risk factors among children in 4 health areas of Kisantu health zone. Methods. A cross-sectional study was carried out in 4 health areas of Kisantu health zone. 388 children randomly selected were screened for S. mansoni using Kato Katz technique and the sociodemographic data was collected. Data were entered and encoded using software EpiData version 3.1. Analysis was performed using SPSS version 21 software. Results. The prevalence of S. mansoni was 26.5% (103; almost two-thirds (63 (61.2% had light infection intensity. A significant association was found between S. mansoni infection and age (p=0.005, educational level (p=0.001, and practices of swimming/bathing (p<0.001 and using water from river/lake/stream for domestic use (p<0.001. Kipasa health area had high prevalence of schistosomiasis (64.6% (64/99; 95% CI 54.4–74.0 compared to other health areas. Conclusion. Schistosoma mansoni infection still remains a public health problem in these areas. There is a need to promote health education and promote behavioral changes in children towards schistosomiasis.

In silico repositioning-chemogenomics strategy identifies new drugs with potential activity against multiple life stages of Schistosoma mansoni.

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Bruno J Neves

2015-01-01

Full Text Available Morbidity and mortality caused by schistosomiasis are serious public health problems in developing countries. Because praziquantel is the only drug in therapeutic use, the risk of drug resistance is a concern. In the search for new schistosomicidal drugs, we performed a target-based chemogenomics screen of a dataset of 2,114 proteins to identify drugs that are approved for clinical use in humans that may be active against multiple life stages of Schistosoma mansoni. Each of these proteins was treated as a potential drug target, and its amino acid sequence was used to interrogate three databases: Therapeutic Target Database (TTD, DrugBank and STITCH. Predicted drug-target interactions were refined using a combination of approaches, including pairwise alignment, conservation state of functional regions and chemical space analysis. To validate our strategy, several drugs previously shown to be active against Schistosoma species were correctly predicted, such as clonazepam, auranofin, nifedipine, and artesunate. We were also able to identify 115 drugs that have not yet been experimentally tested against schistosomes and that require further assessment. Some examples are aprindine, gentamicin, clotrimazole, tetrabenazine, griseofulvin, and cinnarizine. In conclusion, we have developed a systematic and focused computer-aided approach to propose approved drugs that may warrant testing and/or serve as lead compounds for the design of new drugs against schistosomes.

Aspectos ultraestruturais de hemócitos de Biomphalaria glabrata Say (1818 (Gastropoda: Planorbidae analisados sob microscopia eletrônica de transmissão Ultrastructural aspects of hemocytes from Biomphalaria glabrata Say (1818 (Gastropoda: Planorbidae analysed with transmission eletronic microscopy

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Marco Antonio Vasconcelos Santos

2009-09-01

Full Text Available Os hemócitos do caramujo Biomphalaria glabrata, um importante transmissor do trematódeo Schistosoma mansoni no Brasil, foram coletados de especimens na região Bragantina, localizada a oeste do estado do Pará. Os hemócitos foram examinados por meio de microscopia eletrônica de transmissão. As células foram fixadas pelo método de rotina com o uso do tampão PHEM (PIPES, HEPES, EGTA e Magnésio. Foram descritos os aspectos ultra-estruturais celulares como inclusões citoplasmáticas limitadas por membranas, mitocôndrias, retículos endoplasmáticos e outros. As observações mostram que esse tampão possui a propriedade de preservação do citoesqueleto celular, apresentando bons resultados na preservação das estruturas dos hemócitos e suas organelas.The blood cells of the pulmonate snail Biomphalaria glabrata from the region of Bragantina in the state of Pará, an important vector of the trematode Schistosoma mansoni in Brazil, were collected and fixed by routine method with PHEM buffer and examined with transmission electron microscopy. Ultrastructural cellular aspects like cytoplasmic inclusions, mitochondrion, vesicles and others organelles are described. The buffer used resulted in good preservations of the hemocytes and their organelles.

Schistosoma mansoni: assessment of effects of oleic acid, cercarial age and water temperature on parasite-host attraction.

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Lee, Vivien S T; Burgess, Jefferey L; Sterling, Charles R; Lutz, Eric A

2013-09-01

Although the lifecycle of Schistosoma spp. and pathophysiology of schistosomiasis have been established, the mechanism by which cercariae find their host is not well understood. Speculatively, host infection by random and accidental host contact is not as biologically plausible as a biochemical mechanism of mammalian attraction. A few studies have indicated that biochemical cues and temperature gradients may play a role in host identification, attraction and attachment triggers. This study aimed to elucidate these mechanisms more specifically through evaluation of biochemical, age and temperature influences leading to Schistosoma mansoni cercariae attraction and attachment behaviors. Oleic acid, a common unsaturated free fatty acid in the outer layer of human skin, was tested for cercariae attraction across biologically relevant concentrations. Influence of media type (beeswax, nail varnish and agar), age-dependent behavior variability and environmentally appropriate temperatures (22 and 30 °C) were also evaluated. Results indicated that oleic acid at concentrations of 0.3, 0.9 and 1.8 g/mL in beeswax significantly increased median attachment to media (median attachment of 7.50%, 4.20% and 3.71%, respectively, P0.05). Biochemical, age and environmental factors influencing cercarial host attraction and attachment behavior have been elucidated by this study. This information will inform further development of devices for environmental surveillance and potentially improve cercarial exposure prevention strategies. Copyright © 2013 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Effect of oxamniquine on cell adhesion to Schistosoma mansoni larvae in the peritoneal cavity of naive mice Efeito da oxamniquina sobre a adesão celular da larva do S. mansoni na cavidade peritoneal de camundongos

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Alan Lane de Melo

1993-06-01

Full Text Available The treatment of naive mice with high closes of oxamniquine, 1 hour before the intraperitoneal inoculation of Schistosoma mansoni cercariae, induces a delay in the transformation process resulting in a longer host cell adhesion.O tratamento de camundongos sem infecção prévia com altas doses de oxamniquina, 1 hora antes do inóculo intraperitoneal com cercárias de Schistosoma mansoni, induz a um atraso no processo de transformação, resultando conseqüentemente em larvas com adesão celular mais duradoura.

Immunization of pigs against infection with Schistosoma japonicum using ultraviolet-attenuated cercariae

International Nuclear Information System (INIS)

Shi, Y.-E.; Jiang, C.-F.; Han, J.-J.; Li, Y.-L.

1993-01-01

Since pigs are important in the zoonotic transmission of schistosomiasis japonica in China, a veterinary vaccine might contribute to the control of the disease in humans. Pigs were immunized with three doses each of 10 000 cercariae of Schistosoma japonicum attenuated with ultraviolet light (400 μWatt.min/cm 2 ). The experiment was performed with portable irradiation equipment in a rural area of the Hubei Province (P.R. China). A challenge infection of 1000 untreated cercariae was given 2.5 or 6 months after the last immunization, and age-matched naive pigs were challenged as a control. Immunized pigs developed about 90% resistance against the challenge. The liver egg load of these animals was reduced by over 90%. Less than 0.01% of the immunizing cercariae developed to adult parasites and the vaccination had no apparent adverse influence on the pig's health. (Author)

[Helminth burden of slaughter sheep in Upper Bavaria. 1: Species spectrum, infestation extent and infestation intensity].

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Rehbein, S; Kollmannsberger, M; Visser, M; Winter, R

1996-05-01

The helminth fauna of 136 slaughtered sheep (99 lambs or = 1 year) from Upper Bavaria, Germany, was examined. In all 2 species of trematodes, 3 species of cestodes and 24 species of nematodes were found. All the animals harboured gastrointestinal nematodes, 9 of them liver flukes, 33 Moniezia spp., 19 Cysticercus tenuicollis, and one sheep Setaria sp. Lungworms were not seen. The most prevalent species were Cooperia curticei (74.3%), Trichuris ovis (69.1%), Ostertagia circumcincta (68.4%), Oesophagostomum venulosum (63.2%) and Chabertia ovina (61.8%). The highest mean wormburden was seen in Cooperia curticei (12471) followed by Trichostrongylus axei (1856), Trichostrongylus colubriformis (1752), Nematodirus filicollis (1551) and Nematodirus battus (1238). In both lambs and older sheep the small intestine harboured the highest wormburden followed by abomasum and large intestine. The total nematode counts were much higher in lambs than in older sheep. The lambs harboured more intestinal nematodes than older sheep but fewer abomasal worms.

Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

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Shuhua Xiao

2002-07-01

Full Text Available Progress has been made over the last decade with the development and clinical use of artemether as an agent against major human schistosome parasites. The tegument has been identified as a key target of artemether, implying detailed studies on ultrastructural damage induced by this compound. We performed a temporal examination, employing a transmission electron microscope to assess the pattern and extent of ultrastructural alterations in adult Schistosoma mansoni harboured in mice treated with a single dose of 400 mg/kg artemether. Eight hours post-treatment, damage to the tegument and subtegumental structures was seen. Tegumental alterations reached a peak 3 days after treatment and were characterized by swelling, fusion of distal cytoplasma, focal lysis of the tegumental matrix and vacuolisation. Tubercles and sensory organelles frequently degenerated or collapsed. Typical features of subtegumental alterations, including muscle fibres, syncytium and parenchyma tissues, were focal or extensive lysis, vacuolisation and degeneration of mitochondria. Severe alterations were also observed in gut epithelial cells and vitelline cells of female worms. Our findings of artemether-induced ultrastructural alterations in adult S. mansoni confirm previous results obtained with juvenile S. mansoni and S. japonicum of different ages.

Studies on Antigenic Communities between the Yamanashi and Chinese Strains of Schistosoma japonicum Eggs and Oncomelania Snails by Immunoelectrophoresis

OpenAIRE

Iwanaga, Yuzuru; Tsuji, Moriyasu; Tanaka, Noriyasu

1988-01-01

Antigenic communities were studied with sera from rabbits immunized with the Yamanashi and Chinese strains of Schistosoma japonicum eggs, and the antigens of five subspecies of Oncomelania snails, by immunoelectrophoresis. With regard to antigenic communities defined by the Yamanashi strain of S. japonicum eggs and Oncomelania snails, the schistosome egg produced 5 to 6 bands with Oncomelania hupensis nosophora, 3 to 4 bands with O.h.hupensis, 3 bands with O.h.chiui, 2 bands with O.h.quad...

The temperature--dependent expression of GST of Schistosoma japonicum (Philippine strain).

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Cai, Z H; Song, G C; Xu, Y X; Liu, S X

1993-03-01

Obtained from pSj5, the cDNA gene encoding GST antigen of Schistosoma japonicum (Philippine strain) was ligated with efficient temperature-dependent PBV220 vector which was constructed in CAPM, and then introduced into host bacterium-DH5 alpha (E. coli) by transformation. Transformants were selected by ampicillin and recombinant clones were identified by restriction mapping. The result showed that recombinant clone 43 was the one carrying recombinant plasmid PBV 220 with the correct insertion of the gene fragment. The GST expression ability of clone 43 was investigated by GST enzymic activity assay and SDS-PAGE. A relatively high level of GST enzymic activity was expressed by this clone under the temperature-dependent condition, that is, cultured at 30 degrees C and expressed at 42 degrees C. A more strongly stained 26 kDa protein band was identified by SDS-PAGE. The result indicated that GST of S. japonicum (Philippine strain) could be expressed not only by IPTG induction, but also by the temperature-dependent method.

Field testing of Schistosoma japonicum DNA vaccines in cattle in China.

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Shi, Fuhui; Zhang, Yaobi; Lin, Jiaojiao; Zuo, Xin; Shen, Wei; Cai, Yiumin; Ye, Ping; Bickle, Quentin D; Taylor, Martin G

2002-11-01

Vaccines are needed to reduce the zoonotic reservoir of Schistosoma japonicum infection in bovines in China. We have developed two experimental DNA vaccines and have already shown these to be capable of inducing partial protection in water buffalo naturally exposed to the risk of S. japonicum infection in the field. We now report a similar field trial in cattle, the other major bovine reservoir host species in China. Groups of cattle were vaccinated with the VRSj28 vaccine or the VRSj23 vaccine, or, to test whether protection could be enhanced by combination vaccination, with both these DNA vaccines together. After vaccination, the cattle were exposed to natural infection in the field for a period of 54 days. Worm and egg counts carried out at the end of the experiment showed that each of the vaccine groups showed partial resistance, and that combined vaccination was not more effective than vaccination with the individual plasmids.

Comparative Analysis of Proteome-Wide Lysine Acetylation in Juvenile and Adult Schistosoma japonicum

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Qing Li

2017-11-01

Full Text Available Schistosomiasis is a devastating parasitic disease caused by tremotodes of the genus Schistosoma. Eggs produced by sexually mature schistosomes are the causative agents of for pathogenesis and transmission. Elucidating the molecular mechanism of schistosome development and sexual maturation would facilitate the prevention and control of schistosomiasis. Acetylation of lysine is a dynamic and reversible post-translational modification playing keys role in many biological processes including development in both eukaryotes and prokaryotes. To investigate the impacts of lysine acetylation on Schistosoma japonicum (S. japonicum development and sexual maturation, we used immunoaffinity-based acetyllysine peptide enrichment combined with mass spectrometry (MS, to perform the first comparative analysis of proteome-wide lysine acetylation in both female and male, juvenile (18 days post infection, 18 dpi and adult (28 dpi schistosome samples. In total, we identified 874 unique acetylated sites in 494 acetylated proteins. The four samples shared 47 acetylated sites and 46 proteins. More acetylated sites and proteins shared by both females and males were identified in 28 dpi adults (189 and 143, respectively than in 18 dpi schistosomula (76 and 59, respectively. More stage-unique acetylated sites and proteins were also identified in 28 dpi adults (494 and 210, respectively than in 18 dpi schistosomula (73 and 44, respectively. Functional annotation showed that in different developmental stages and genders, a number of proteins involving in muscle movement, glycometabolism, lipid metabolism, energy metabolism, environmental stress resistance, antioxidation, etc., displayed distinct acetylation profiles, which was in accordance with the changes of their biological functions during schistosome development, suggesting that lysine acetylation modification exerted important regulatory roles in schistosome development. Taken together, our data provided the first

Identification of Schistosoma mansoni candidate antigens for diagnosis of schistosomiasis

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Gardenia Braz Figueiredo Carvalho

2011-11-01

Full Text Available The development of a more sensitive diagnostic test for schistosomiasis is needed to overcome the limitations of the use of stool examination in low endemic areas. Using parasite antigens in enzyme linked immunosorbent assay is a promising strategy, however a more rational selection of parasite antigens is necessary. In this study we performed in silico analysis of the Schistosoma mansoni genome, using SchistoDB database and bioinformatic tools for screening immunogenic antigens. Based on evidence of expression in all parasite life stage within the definitive host, extracellular or plasmatic membrane localization, low similarity to human and other helminthic proteins and presence of predicted B cell epitopes, six candidates were selected: a glycosylphosphatidylinositol-anchored 200 kDa protein, two putative cytochrome oxidase subunits, two expressed proteins and one hypothetical protein. The recognition in unidimensional and bidimensional Western blot of protein with similar molecular weight and isoelectric point to the selected antigens by sera from S. mansoni infected mice indicate a good correlation between these two approaches in selecting immunogenic proteins.

Activity of praziquantel on in vitro transformed Schistosoma mansoni sporocysts

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ACA Mattos

2006-10-01

Full Text Available Praziquantel (PZQ is effective against all the evolutive phases of Schistosoma mansoni. Infected Biomphalaria glabrata snails have their cercarial shedding interrupted when exposed to PZQ. Using primary in vitro transformed sporocysts, labeled with the probe Hoechst 33258 (indicator of membrane integrity, and lectin of Glycine max (specific for carbohydrate of N-acetylgalactosamine membrane, we evaluated the presence of lysosomes at this evolutive phase of S. mansoni, as well as the influence of PZQ on these acidic organelles and on the tegument of the sporocyst. Although the sporocyst remained alive, it was observed that there was a marked contraction of its musculature, and there occurred a change in the parasite's structure. Also, the acidic vesicles found in the sporocysts showed a larger delimited area after contact of the parasites with PZQ. Damages to the tegument was also observed, as show a well-marked labeling either with Hoechst 33258 or with lectin of Glycine max after contact of sporocysts with the drug. These results could partially explain the interruption/reduction mechanism of cercarial shedding in snails exposed to PZQ.

Radiation-resistant acquired immunity of vaccinated mice to Schistosoma mansoni

International Nuclear Information System (INIS)

Aitken, R.; Coulson, P.S.; Dixon, B.; Wilson, R.A.

1987-01-01

Vaccination of mice with attenuated cercariae of Schistosoma mansoni induces specific acquired resistance to challenge infection. This resistance is immunologically-mediated, possibly via a delayed-type hypersensitivity. Studies of parasite migration have shown that the protective mechanism operates most effectively in the lungs of vaccinated mice. We have probed the mechanism by exposing mice to 500 rads of gamma radiation before challenge infection. Our results show that the effector mechanism operative against challenge larvae is resistant to radiation. In contrast, classical immune responses are markedly suppressed by the same treatment. While leukocyte populations in the blood fall dramatically after irradiation, numbers of cells recoverable by bronchoalveolar lavage are unaffected. We suggest that vaccination with attenuated cercariae establishes populations of sensitized cells in the lungs which trigger the mechanism of resistance when challenge schistosomula migrate through pulmonary capillary beds. Although the cells may be partially disabled by irradiation, they remain responsive to worm antigens and thereby capable of initiating the elimination mechanism. This hypothesis would explain the radiation resistance of vaccine-induced immunity to S. mansoni

Tegumental Ca-stimulated adenosine triphosphatase activity in adult Schistosoma mansoni worms Atividade da adenosina trifosfatase estimulada pelo Ca no tegumento de vermes adultos de Schistosoma mansoni

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Italo M. Cesari

1989-09-01

Full Text Available A Ca-stimulated ATPase activity (pH 9.5 associated with the tegumental membrane enriched (TME fraction of Schistosoma mansoni adults was partially inhibited by NAP-taurine or by increasing concentrations of chlorpromazine; endogenous calmodulin was found associated with the TME fraction. A similar activity (pH 8.6 was histochemically visualized whithin the tegument of fixed worms on the cytoplasmic leaflet of both the doubel surface membrane and the basement membrane; this reaction was inhibited by 1 µM chloropromazine and it was also observed on the inner side of double membrane vesicles present in the TME fraction. No ATPase activity could be seen at alkaline pH with added Mg or Na/K ions. Without ATP, the addition of external Ca to the fixed worms induced the appearance of lead precipitates on the tegumental discoid bodies; this reaction was inhibited by molybdate and not by chlorpromazine. The intrategumentary regulation of calcium by the systems described and the possible use of phenothiazines against schistosimes are discussed.A atividade ATPse (pH 9.5 estimulada por ions de Ca associados a uma fração enriquecida de membranas do tegumento (fração EMT de vermes adultos de Schistosoma mansoni, foi inibida pro NAP-taurina ou por concentrações crescentes de clorpromacina. Foi encontrada calmodulina enfogena associada principlamente a esta fração. Em vermes adultos fixados com glutaraldeido se detectou histoquimicamente uma atividade ATPase similar (pH 8.6 na face citoplasmática da dupla membrana de superfície e da membrana por 1 µM de clorpromacina e foi também observada na face interna de vesículas de dupla membrana presentes na fração EMT. Não se pôde detectar atividade ATpase em pH alcalino na presença de ions de Mg ou Na/K. A adição externa de Ca, sem ATP, aos vermes fixados induz ao aparecimento de precipitados nos corpos discóides do tegumento; esta reação foi inibida. Os resultados são discutidos em relação a

Parasite manipulation of brain monoamines in California killifish (Fundulus parvipinnis) by the trematode Euhaplorchis californiensis

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Shaw, J.C.; Korzan, W.J.; Carpenter, R.E.; Kuris, A.M.; Lafferty, K.D.; Summers, C.H.; Overli, O.

2009-01-01

California killifish (Fundulus parvipinnis) infected with the brain-encysting trematode Euhaplorchis californiensis display conspicuous swimming behaviours rendering them more susceptible to predation by avian final hosts. Heavily infected killifish grow and reproduce normally, despite having thousands of cysts inside their braincases. This suggests that E. californiensis affects only specific locomotory behaviours. We hypothesised that changes in the serotonin and dopamine metabolism, essential for controlling locomotion and arousal may underlie this behaviour modification. We employed micropunch dissection and HPLC to analyse monoamine and monoamine metabolite concentrations in the brain regions of uninfected and experimentally infected fish. The parasites exerted density-dependent changes in monoaminergic activity distinct from those exhibited by fish subjected to stress. Specifically, E. californiensis inhibited a normally occurring, stress-induced elevation of serotonergic metabolism in the raphae nuclei. This effect was particularly evident in the experimentally infected fish, whose low-density infections were concentrated on the brainstem. Furthermore, high E. californiensis density was associated with increased dopaminergic activity in the hypothalamus and decreased serotonergic activity in the hippocampus. In conclusion, the altered monoaminergic metabolism may explain behavioural differences leading to increased predation of the infected killifish by their final host predators. ?? 2008 The Royal Society.

Invasion biology meets parasitology: a case study of parasite spill-back with Egyptian Fasciola gigantica in the invasive snail Pseudosuccinea columella.

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Daniel S Grabner

Full Text Available The liver fluke Fasciola gigantica is a trematode parasite of ruminants and humans that occurs naturally in Africa and Asia. Cases of human fascioliasis, attributable at least in part to F. gigantica, are significantly increasing in the last decades. The introduced snail species Galba truncatula was already identified to be an important intermediate host for this parasite and the efficient invader Pseudosuccinea columella is another suspect in this case. Therefore, we investigated snails collected in irrigation canals in Fayoum governorate in Egypt for prevalence of trematodes with focus on P. columella and its role for the transmission of F. gigantica. Species were identified morphologically and by partial sequencing of the cytochrome oxidase subunit I gene (COI. Among all 689 snails found at the 21 sampling sites, P. columella was the most abundant snail with 296 individuals (42.96% and it was also the most dominant species at 10 sites. It was not found at 8 sites. Molecular detection by PCR and sequencing of the ITS1-5.8S-ITS2 region of the ribosomal DNA (rDNA revealed infections with F. gigantica (3.38%, Echinostoma caproni (2.36% and another echinostome (7.09% that could not be identified further according to its sequence. No dependency of snail size and trematode infection was found. Both high abundance of P. columella in the Fayoum irrigation system and common infection with F. gigantica might be a case of parasite spill-back (increased prevalence in local final hosts due to highly susceptible introduced intermediate host species from the introduced P. columella to the human population, explaining at least partly the observed increase of reported fascioliasis-cases in Egypt. Eichhornia crassipes, the invasive water hyacinth, which covers huge areas of the irrigation canals, offers safe refuges for the amphibious P. columella during molluscicide application. As a consequence, this snail dominates snail communities and efficiently transmits

Genetic diversity of Schistosoma haematobium parasite IS NOT associated with severity of disease in an endemic area in Sudan.

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Gasmelseed, Nagla; Karamino, Nhashal E; Abdelwahed, Mohammed O; Hamdoun, Anas O; Elmadani, Ahmed E

2014-08-27

Over 650 million people globally are at risk of schistosomiasis infection, while more than 200 million people are infected of which the higher disease rates occur in children. Eighty three students between 6-20 years (mean 12.45 ± 3.2) from Quran School for boys in Radwan village, Gezira state were recruited to investigate for the relationship between the genetic diversity of Schistosoma haematobium strains and the severity of the disease. Schistosoma haematobium infection was detected by filtration of urine. Ultrasonography was done on each study subject, while PCR technique was used for genotyping via random amplified polymorphic DNA (RAPD) with A01, A02, A12, Y20 and A13 primers. A01 primer gave three different genotypes (A01-1, A01-2 and A01-3). About 54.2% (45/83) were S. haematobium egg positive by urine filtration. On assessment of the upper and lower urinary tract by ultrasound technique, 61.4% (51/83) were positiveand73.3% (60/83) samples were PCR positive. No significant difference was found when comparing the three different genotypes with severity of the disease. This study concludes that no association was found between the different genotypes of S.haemtobium and the severity of the disease. Examination of more samples from different areas to identify any possible differences between the parasites genes and disease severity was recommended.

Hemiuroid trematode sporocysts are undetected by hemocytes of their intermediate host, the ark cockle Anadara trapezia: potential role of surface carbohydrates in successful parasitism.

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Kawasaki, Minami; Delamare-Deboutteville, Jerome; Dang, Cecile; Barnes, Andrew C

2013-12-01

In order to establish a successful relationship with their hosts, parasites must subvert or evade immune defences. Cockle Anadara trapezia and Sydney Rock oyster (SRO) Saccostrea glomerata live in the same location but only ark cockles are infected by sporocysts of hemiuroid trematode. This provides an opportunity to explore differing interactions between the parasite and the immune system of susceptible and refractive hosts. Rapid migration and encapsulation of sporocysts was observed by SRO hemocytes but not by cockle hemocytes. This migration/encapsulation was inhibited by N-acetylglucosamine or N-acetylgalactosamine but not by the other sugars, implicating specific surface carbohydrates in immune detection. Effector responses of hemocytes were investigated in vitro in terms of production of reactive oxygen production (ROS). Hemocytes of both species strongly reacted to Zymosan, but only SRO hemocytes responded to live sporocysts. Neither species' hemocytes produced ROS in the presence of dead/fixed sporocysts, and there was no suppression of Zymosan-induced respiratory burst by sporocysts. This suggests that immune escape is mediated by avoiding encapsulation, perhaps through molecular mimicry. Membrane-shaving with proteases indicated that sporocyst surface proteins are not a key factors in hemocytic detection. Surface carbohydrates of SRO and cockle hemocytes and of sporocysts were profiled with a panel of biotinylated lectins. This revealed substantial differences between cockle and SRO hemocytes, but greater similarity between cockle hemocytes and sporocysts. Results suggest that surface carbohydrates play an integral role in hemocyte immunorecognition and that surface carbohydrate molecular mimicry is a potential strategy for immune evasion in cockles by hemiuroid trematode sporocysts. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Identification of lead chemotherapeutic agents from medicinal plants against blood flukes and whipworms.

Science.gov (United States)

Wangchuk, Phurpa; Giacomin, Paul R; Pearson, Mark S; Smout, Michael J; Loukas, Alex

2016-08-30

Schistosomiasis and trichuriasis are two of the most common neglected tropical diseases (NTD) that affect almost a billion people worldwide. There is only a limited number of effective drugs to combat these NTD. Medicinal plants are a viable source of parasiticides. In this study, we have investigated six of the 19 phytochemicals isolated from two Bhutanese medicinal plants, Corydalis crispa and Pleurospermum amabile, for their anthelmintic properties. We used the xWORM technique and Scanning Electron Microscope-based imaging to determine the activity of the compounds. Of the six compounds tested, isomyristicin and bergapten showed significant anthelmintic activity against Schistosoma mansoni and Trichuris muris with bergapten being the most efficacious compound one against both parasites (S. mansoni IC50 = 8.6 μg/mL and T. muris IC50 = 10.6 μg/mL) and also against the schistosomulum stage of S. mansoni. These two compounds induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. The efficacy against multiple phylogenetically distinct parasites and different life stages, especially the schistosomulum where praziquantel is ineffective, makes isomyristicin and bergapten novel scaffolds for broad-spectrum anthelmintic drug development that could be used for the control of helminths infecting humans and animals.

Pulmonary leukocytic responses are linked to the acquired immunity of mice vaccinated with irradiated cercariae of Schistosoma mansoni

International Nuclear Information System (INIS)

Aitken, R.; Coulson, P.S.; Wilson, R.A.

1988-01-01

Pulmonary cellular responses in C57BL/6 mice exposed to Schistosoma mansoni have been investigated by sampling cells from the respiratory airways with bronchoalveolar lavage. Mice exposed to cercariae attenuated with 20 krad gamma-radiation developed stronger and more persistent pulmonary leukocytic responses than animals exposed to equal numbers of normal parasites. Although vaccination with irradiated cercariae also stimulated T cell responses of greater magnitude and duration than normal infection, the lymphocytic infiltrate elicited by each regimen did not differ substantially in its composition, 5 wk after exposure. Studies with cercariae attenuated by different treatments established that a link exists between the recruitment of leukocytes to the lungs of vaccinated mice and resistance to reinfection. There was a strong association between pulmonary leukocytic responses and the elimination of challenge infections by vaccinated mice. Animals exposed to irradiated cercariae of S. mansoni were resistant to homologous challenge infection but were not protected against Schistosoma margrebowiei. Homologous challenge of vaccinated mice stimulated anamnestic leukocytic and T lymphocytic responses in the lungs, 2 wk postinfection, but exposure of immunized animals to the heterologous species failed to trigger an expansion in these populations of cells. Our studies indicate that pulmonary leukocytes and T lymphocytes are intimately involved in the mechanism of vaccine-induced resistance to S. mansoni. It remains unclear whether these populations of cells initiate protective inflammatory reactions against challenge parasites in the lungs, or accumulate in response to the activation of the protective mechanism by other means

Differential pulmonic NK and NKT cell responses in Schistosoma japonicum-infected mice.

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Cha, Hefei; Qin, Wenjuan; Yang, Quan; Xie, Hongyan; Qu, Jiale; Wang, Mei; Chen, Daixiong; Wang, Fang; Dong, Nuo; Chen, Longhua; Huang, Jun

2017-02-01

Natural killer cells (NK cells) and natural killer T cells (NKT cells) play a role in anti-infection, anti-tumor, transplantation immunity, and autoimmune regulation. However, the role of NK and NKT cells during Schistosoma japonicum (S. japonicum) infection has not been widely reported, especially regarding lung infections. The aim of this study was to research the NK and NKT cell response to S. japonicum infection in the lungs of mice. Using immunofluorescent histological analysis, NK and NKT cells were found near pulmonary granulomas. Moreover, flow cytometry revealed that the percentage and number of pulmonic NK cells in S. japonicum-infected mice were significantly increased (P cell number of NKT cells were decreased compared to those of normal mice (P NKT cells was increased after infection (P NKT cells (P cells (P NKT cells significantly increased (P NKT cells (P NKT cell activation during S. japonicum infection.

Recombinant adenylate kinase 3 from liver fluke Clonorchis sinensis for histochemical analysis and serodiagnosis of clonorchiasis.

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Kwon, Soon Bin; Kim, Paul; Woo, Hae Sun; Kim, Tae Yun; Kim, Ju Yeong; Lee, Hye Min; Jang, Yun Soo; Kim, Eun-Min; Yong, Tai-Soon; Seong, Baik Lin

2018-03-27

Due to the lack of an effective prophylactic intervention and diagnosis, human liver fluke Clonorchis sinensis continues to afflict a large human population, causing a chronic inflammatory bile duct disease. With an aim to identify target antigens for sensitive serodiagnosis, adenylate kinase 3 of C. sinensis (CsAK3) was successfully expressed in soluble form in Escherichia coli by fusion to an RNA-interacting domain derived from human Lys-tRNA synthetase and purified by Ni2+-affinity chromatography. Anti-CsAK3 serum was raised by immunization of mice, and Western blotting confirmed that CsAK3 was expressed in adult-stage C. sinensis. Histochemical analysis showed that CsAK3 was localized to the subtegumental tissue of C. sinensis and was excreted into the bile duct of the host. When tested against sera from various parasite-infected patients by enzyme-linked immunosorbent assay, the recombinant CsAK3 elicited a specific response to C. sinensis-infected sera. The results suggest that CsAK3, either alone or in combination with other antigens, could be used for improving the clinical diagnosis of clonorchiasis.

Case–Control Study of Posttreatment Regression of Urinary Tract Morbidity among Adults in Schistosoma haematobium–Endemic Communities in Kwale County, Kenya

Science.gov (United States)

Magak, Philip; Chang-Cojulun, Alicia; Kadzo, Hilda; Ireri, Edmund; Muchiri, Eric; Kitron, Uriel; King, Charles H.

2015-01-01

Previous population-based studies have examined treatment impact on Schistosoma-associated urinary tract disease among children, but much less is known about longer-term treatment benefits for affected adult populations in areas where risk of recurrent infection is high. In communities in Msambweni, along the Kenya coast, we identified, using a portable ultrasound, 77 adults (aged 17–85) with moderate-to-severe obstructive uropathy or bladder disease due to Schistosoma haematobium. Treatment response was assessed by repeat ultrasound 1–2 years after praziquantel (PZQ) therapy and compared with interval changes among age- and sex-matched infected/treated control subjects who did not have urinary tract abnormalities at the time of initial examination. Of the 77 affected adults, 62 (81%) had improvement in bladder and/or kidney scores after treatment, 14 (18%) had no change, and one (1.3%) had progression of disease. Of the 77 controls, 75 (97%) remained disease free by ultrasound, while two (3%) had apparent progression with abnormal findings on follow-up examination. We conclude that PZQ therapy for S. haematobium is effective in significantly reducing urinary tract morbidity from urogenital schistosomiasis among adult age groups, and affected adults stand to benefit from inclusion in mass treatment campaigns. PMID:26013375

The presence of Fasciola hepatica (Liver-fluke in humans and cattle from a 4,500 Year old archaeological site in the Saale-Unstrut Valley, Germany

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Dittmar K

2003-01-01

Full Text Available During an excavation of a site of the corded ware culture in the Saale-Unstrut-Valley (ca. 3000 BC in Germany, a soil sample from the pelvis of a human skeleton was studied under palaeoparasitological aspects. Eggs of the trematode Fasciola hepatica and of the nematode genus Capillaria were found. This is the first case of a direct association of a F. hepatica-infestation to both a prehistoric human skeleton and domesticated animal remains. Sheep and cattle bones were present at the same site and F. hepatica eggs were found in bovine samples. This strongly points toward an existing infection cycle, involving humans as a final host.

Modeling the distribution of Schistosoma mansoni and host snails in Uganda using satellite sensor data and Geographical Information Systems

DEFF Research Database (Denmark)

Stensgaard, Anna-Sofie; Jørgensen, A; Kabatereine, N B

2005-01-01

The potential value of MODIS satellite sensor data on Normalized Difference Vegetation Index (NDVI) and land surface temperatures (LST) for describing the distribution of the Schistosoma mansoni-"Biomphalaria pfeifferi"/Biomphalaria sudanica parasite-snail system in inland Uganda, were tested...... by developing annual and seasonal composite models, and iteratively analysing for their relationship with parasite and snail distribution. The dry season composite model predicted an endemic area that produced the best fit with the distribution of schools with > or =5% prevalence. NDVI values of 151-174, day...

UVB-induced immune suppression and infection with Schistosoma mansoni

International Nuclear Information System (INIS)

Noonan, F.P.; Lewis, F.A.

1995-01-01

Irradiation with ultraviolet B (UVB, 290-320 nm) causes a systematic immunosuppression of cell-mediated immunity. The question of whether UV immunosuppression modulates the course of infectious diseases is important because UVB levels in sunlight are sufficient to predict significant UV-induced immunosuppression at most latitudes. We have investigated the effect of immunosuppressive doses of UVB on the disease caused by the helminth parasite Schistosoma mansoni. C57BL/6 mice were irradiated once or three times weekly over 60-80 days with UV from a bank of FS40 sunlamps. Each UV treatment consisted of an immunosuppressive UV dose, as determined by suppression of contact hypersensitivity to trinitrochlorobenzene, corresponding to about 15-30 min of noonday tropical sunlight exposure under ideal clear sky conditions. Cumulative UV doses were between 80 and 170 kJ/m 2 . Worm and egg burdens, liver granuloma diameters and liver fibrosis showed minimal changes ( 2 administered in six treatments) did not impair the resistance to rechallenge conferred by vaccination with 60 Co-irradiated cercariae. We have observed a dichotomy between UV immnosuppression and both disease and vaccination in this helminth infection, in contrast to the effects of UVB shown in other infectious diseases. (author)

Development of Schistosoma mansoni in Biomphalaria tenagophila, Biomphalaria straminea and Biomphalaria glabrata Desenvolvimento do Schistosoma mansoni em Biomphalaria tenagophila, Biomphalaria straminea e Biomphalaria glabrata

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Cecilia Pereira de Souza

1995-06-01

Full Text Available A comparative study of the development of Schistosoma mansoni during the intra-molluscan phase was made by means of histological sections of Biomphalaria tenagophila, B. straminea and B. glabrata from Brazil. Two hundred snails of each species were individually exposed to 50 miracidia of the S. mansoni, AL line. No larvae were observed in the snails fixed 72 h after exposure. In specimens shedding cercariae, 31 days after exposure tissue reactions encapsulating the larvae were seen in B. tenagophila and B. straminea, in the head-foot, mantle collar and renal ducts. No tissue reactions occurred in the digestive glands of these two species. In B. glabrata the presence of numerous sporocysts and cercariae without tissue reactions was observed in the digestive gland, and other organs. The levels of infection of the snails and the average numbers of cercariae shed per day were 32.6% and 79±90 respectively for B. tenagophila, 11.3% and 112±100 for B. straminea and 75.3% and 432±436 for B. glabrata. The lower levels of infection and average numbers of cercariae shed by B. tenagophila and B. straminea are thus related to their more potent internal defense systems.Foi feito estudo comparativo do desenvolvimento do Schistosoma mansoni na fase intra-molusco, através de cortes histológicos, em Biomphalaria tenagophila, B. straminea e B. glabrata. Duzentos moluscos de cada espécie foram expostos individualmente a 50 miracídios de S. mansoni da linhagem AL. Nenhuma larva foi observada nos exemplares fixados 72 horas após a exposição. Nos exemplares eliminando cercárías, 31 dias após a exposição, foram observadas reações teciduais de encapsulamento de larvas em B. tenagophila e B. straminea, na região cefalopodal, colar do manto e dutos renais. Nas glândulas digestivas das duas espécies não foram observadas reações. Em B. glabrata foi registrada a presença de numerosos esporocistos e cercárias sem reação tecidual na gl

Mapping the Pro-Peptide of the Schistosoma mansoni Cathepsin B1 Drug Target: Modulation of Inhibition by Heparin and Design of Mimetic Inhibitors

Czech Academy of Sciences Publication Activity Database

Horn, Martin; Jílková, Adéla; Vondrášek, Jiří; Marešová, Lucie; Caffrey, C. R.; Mareš, Michael

2011-01-01

Roč. 6, č. 6 (2011), s. 609-617 ISSN 1554-8929 R&D Projects: GA ČR GA203/09/1585; GA AV ČR KJB400550516; GA AV ČR IAA400550705 Grant - others:NATO(XE) NATO LST/CLG 980187 Institutional research plan: CEZ:AV0Z40550506 Keywords : Schistosoma mansoni * cathepsin B * propeptide Subject RIV: CE - Biochemistry Impact factor: 6.446, year: 2011

CK2 Phosphorylation of Schistosoma mansoni HMGB1 Protein Regulates Its Cellular Traffic and Secretion but Not Its DNA Transactions

OpenAIRE

de Abreu da Silva, Isabel Caetano; Carneiro, Vitor Coutinho; Maciel, Renata de Moraes; da Costa, Rodrigo Furtado Madeiro; Furtado, Daniel Rodrigues; de Oliveira, Francisco Meirelles Bastos; da Silva-Neto, Mário Alberto Cardoso; Rumjanek, Franklin David; Fantappié, Marcelo Rosado

2011-01-01

BACKGROUND: The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding t...

Worms at war: interspecific parasite competition and host resources alter trematode colony structure and fitness.

Science.gov (United States)

Mouritsen, Kim N; Andersen, Cecillie

2017-09-01

Parasites competing over limited host resources are faced with a tradeoff between reproductive success and host overexploitation jeopardizing survival. Surprisingly little is known about the outcome of such competitive scenarios, and we therefore aimed at elucidating interactions between the trematodes Himasthla elongata and Renicola roscovita coinfecting the periwinkle first intermediate host. The results show that the success of Himasthla colonies (rediae) in terms of cercarial emission is unaffected by Renicola competition (sporocysts), whereas deteriating host condition decreases fitness. Furthermore, double infection has no bearing on Himasthla's colony size but elevated the proportion of non-reproductive rediae that play a decisive role in colony defence. Opposite, the development of the Renicola colony (size/maturity), and in turn fitness, is markedly reduced in presence of Himasthla, whereas the nutritional state of the host appears less important. Hence, the intramolluscan competition between Himasthla and Renicola is asymmetrical, Himasthla being the superior competitor. Himasthla not only adjusts its virulence according to the hosts immediate nutritional state, it also nullifies the negative impact of a heterospecific competitor on own fitness. The latter is argued to follow in part from direct predation on the competitor, for which purpose more defensive non-reproductive rediae are strategically produced.

Beyond Parasitism: Hepatic Lesions in Stranded Harbor Porpoises (Phocoena phocoena) Without Trematode (Campula oblonga) Infections.

Science.gov (United States)

Hiemstra, S; Harkema, L; Wiersma, L C M; Keesler, R I

2015-11-01

The liver can be an indicator of the health of an individual or of a group, which can be especially important to identify agents that can cause disease in multiple species. To better characterize hepatic lesions in stranded harbor porpoises (Phocoena phocoena), we analyzed the livers from 39 porpoises that stranded along the Dutch coast between December 2008 and December 2012. The animals were selected because they had either gross or histologic liver lesions with minimal autolysis and no evidence of trematode (Campula oblonga) infection. The most common finding was a chronic hepatitis (22/39, 56.4%) that was often associated with significant disease reported in another organ system (18/22, 81.8%), of which 14 had chronic systemic disease. One case of chronic hepatitis was so severe as to mimic lymphoma, which could only be differentiated with immunohistochemistry. The other common lesions were lipidosis (11/39, 28.2%) and acute hepatitis (6/39, 15.4%), often in combination with mild chronic changes. Overall, although there were no consistent trends in etiology for the hepatic lesions, lipidosis was associated with starvation (8/11, 72.7%) and acute disease, and acute hepatitis was associated with bacterial infections and sepsis (6/6, 100%). © The Author(s) 2014.

An interesting finding in the uterine cervix: Schistosoma hematobium calcified eggs.

Science.gov (United States)

Toller, Alexia; Scopin, Ana Carolina; Apfel, Vanessa; Prigenzi, Karla Calaça Kabbach; Tso, Fernanda Kesselring; Focchi, Gustavo Rubino de Azevedo; Speck, Neila; Ribalta, Julisa

2015-01-01

Schistosoma hematobium infection is an endemic parasitic disease in Africa, which is frequently associated with urinary schistosomiasis. The parasite infection causes epithelial changes and disruption, facilitating the infection by the human papilloma virus and human immunodeficiency virus (HIV). The authors report the case of a 44-year-old African HIV-positive woman who presented an abnormal routine Pap smear. Colposcopy examination revealed dense acetowhite micropapillary epithelium covering the ectocervix, iodine-negative, an erosion area in endocervical canal, and atypical vessels. Histologic examination of the surgical specimens showed numerous calcified schistosome eggs (probably S. hematobium) and a high-grade cervical intraepithelial neoplasia. The relation between S. hematobium infection and bladder cancer is well known; however, this relationship with cervical cancer remains controversial. The symptoms of schistosomiasis of the female genital tract are rather non-specific, and are often misdiagnosed with other pelvic diseases. The familiarity of health professionals with schistosomiasis of the female genital tract is less than expected, even in endemic regions. Therefore, great awareness of this differential diagnosis in routine gynecological practice is of paramount importance.

Schistosoma mansoni: vaccination of mice with 10-krad-irradiated, cryopreserved schistosomules

International Nuclear Information System (INIS)

Lewis, F.A.; Stirewalt, M.A.; Leef, J.L.

1984-01-01

Protection against a Schistosoma mansoni cercarial challenge was evaluated in mice immunized with a vaccine composed of 10-krad-irradiated, cryopreserved schistosomules. The level of resistance induced in C57B1/6 or NMRI (CV) mice increased with the number of schistosomules injected. Up to 83% reduction in challenge worm burden was achieved when 5000 schistosomules were injected per mouse. Intramuscular injection of the vaccine was superior to subcutaneous. Multiple immunizations, up to 3 at 4-week intervals, did not increase the resistance induced by a single immunization. A high level of protection developed in as little as 2 weeks and was maintained through at least 12 weeks postimmunization. The vaccine irradiated with 10 krad from either a 60-cobalt or 137-cesium source induced equivalent levels of resistance, and no differences were found in the immunogenicity of vaccines comprised of organisms irradiated as cercariae or as 1- to 3-hr-old schistosomules. These findings are basic to the development of a cryopreserved, live vaccine against schistosomiasis of humans or domestic animals

Treatment of Schistosoma mansoni with miltefosine in vitro enhances serological recognition of defined worm surface antigens.

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Marwa H El-Faham

2017-08-01

Full Text Available Miltefosine, an anti-cancer drug that has been successfully repositioned for treatment of Leishmania infections, has recently also shown promising effects against Schistosoma spp targeting all life cycle stages of the parasite. The current study examined the effect of treating Schistosoma mansoni adult worms with miltefosine on exposure of worm surface antigens in vitro.In an indirect immunofluorescence assay, rabbit anti-S.mansoni adult worm homogenate and anti-S. mansoni infection antisera gave strong immunofluorescence of the S. mansoni adult worm surface after treatment with miltefosine, the latter antiserum having previously been shown to synergistically enhance the schistosomicidal activity of praziquantel. Rabbit antibodies that recognised surface antigens exposed on miltefosine-treated worms were recovered by elution off the worm surface in low pH buffer and were used in a western immunoblotting assay to identify antigenic targets in a homogenate extract of adult worms (SmWH. Four proteins reacting with the antibodies in immunoblots were purified and proteomic analysis (MS/MS combined with specific immunoblotting indicated they were the S. mansoni proteins: fructose-1,6 bisphosphate aldolase (SmFBPA, Sm22.6, alkaline phosphatase and malate dehydrogenase. These antibodies were also found to bind to the surface of 3-hour schistosomula and induce immune agglutination of the parasites, suggesting they may have a role in immune protection.This study reveals a novel mode of action of miltefosine as an anti-schistosome agent. The immune-dependent hypothesis we investigated has previously been lent credence with praziquantel (PZQ, whereby treatment unmasks parasite surface antigens not normally exposed to the host during infection. Antigens involved in this molecular mechanism could have potential as intervention targets and antibodies against these antigens may act to increase the drug's anti-parasite efficacy and be involved in the development

Immunization with tegument nucleotidases associated with a subcurative praziquantel treatment reduces worm burden following Schistosoma mansoni challenge

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Henrique K. Rofatto

2013-04-01

Full Text Available Schistosomiasis is a debilitating disease caused by flatworm parasites of the Schistosoma genus and remains a high public health impact disease around the world, although effective treatment with Praziquantel (PZQ has been available since the 1970s. Control of this disease would be greatly improved by the development of a vaccine, which could be combined with chemotherapy. The sequencing of the Schistosoma mansoni transcriptome and genome identified a range of potential vaccine antigens. Among these, three nucleotidases from the tegument of the parasite, presumably involved in purinergic signaling and nucleotide metabolism, were proposed as promising vaccine candidates: an alkaline phosphatase (SmAP, a phosphodiesterase (SmNPP-5 and a diphosphohydrolase (SmNTPDase. Herein, we evaluate the potential of these enzymes as vaccine antigens, with or without subcurative PZQ treatment. Immunization of mice with the recombinant proteins alone or in combination demonstrated that SmAP is the most immunogenic of the three. It induced the highest antibody levels, particularly IgG1, associated with an inflammatory cellular immune response characterized by high TNF-α and a Th17 response, with high IL-17 expression levels. Despite the specific immune response induced, immunization with the isolated or combined proteins did not reduce the worm burden of challenged mice. Nonetheless, immunization with SmAP alone or with the three proteins combined, together with subcurative PZQ chemotherapy was able to reduce the worm burden by around 40%. The immunogenicity and relative exposure of SmAP to the host immune system are discussed, as key factors involved in the apparently synergistic effect of SmAP immunization and subcurative PZQ treatment.

Alterações estruturais na mucosa jejunal de camundongos infectados com Schistosoma mansoni, alimentados com dietas hipo ou hiperprotéicas

OpenAIRE

Couto, Janira Lúcia Assumpção; Ferreira, Haroldo da Silva; Rocha, Dinalva Bezerra da; Duarte, Maria Eugênia Leite; Assunção, Monica Lopes; Coutinho, Eridan de Medeiros

2002-01-01

The effects of high and low-protein diets on the structure of the jejunal mucosa were studied in Schistosoma mansoni infected mice (morphology and histomorphometry). Weaning male albino mice were infected with 80 cercariae, fed with high (20%) or low-protein (5%) diets and compared to uninfected controls under the same conditions. Mice were sacrificed 12 weeks after infection. Animals submitted to a low-protein diet showed lower weight curves, mainly when infected. In the jejunal mucosa, fing...

Síntese e atividade biológica do derivado 6-formil-oxamniquina Synthesis and biological activity of 6-formyl-oxamniquine derivative

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Adélia Emília de Almeida

2008-12-01

Full Text Available A esquistossomose, uma importante doença no Brasil, é causada por trematódeo pertencente ao gênero Schistosoma, atingindo milhões de pessoas, numa das maiores regiões endêmicas dessa doença em todo globo. O principal objetivo desse trabalho foi sintetizar o derivado 6-formil-oxamniquina e avaliar sua atividade biológica. O derivado 6-formil- oxamniquina foi obtido por oxidação da oxamniquina com dióxido de manganês empregando diclorometano como solvente, à temperatura ambiente, por 24 horas. Sua obtenção foi confirmada por espectrometria na região de infravermelho e espectroscopia de RMN 13C e ¹H, apresentando atividade similar quando comparada à oxamniquina comercial (Mansil®.Schistosomiasis, an important disease in Brazil, is caused by a trematode of the genus Schistosoma, reaching millions of person in one of the most endemic region of this disease in the whole globe. The main goal of this work was to syntetize the 6-formyl-oxamniquine derivative and evaluate its biological activity. The 6-formyl-oxamniquine derivative was obtained by the oxidation of oxamniquine with MnO2, applying CH2Cl2 as solvent at room temperature for 24 hours. The obtaintion of 6-formyl-oxamniquine derivative compound was confirmed by IR spectroscopy and 13C NMR and ¹H NMR, presenting similar activity when compared to the commercial oxamniquine (Mansil®.

The induction of species-specific immunity against Schistosoma japonicum by exposure of rats to ultra-violet attenuated cercariae

International Nuclear Information System (INIS)

Moloney, N.A.; Webbe, G.; Hinchcliffe, P.

1987-01-01

Single percutaneous immunizations of Fischer rats with 1000 ultra-violet attenuated Schistosoma japonicum cercariae induced 52-88% resistance to challenge 4 weeks later. Increasing this to 3 immunizations induced 90% resistance to challenge, and this level of protection remained undiminished for up to 40 weeks after vaccination. Rats vaccinated with gamma-irradiated S. mansoni cercariae were resistant to challenge with S. mansoni but not S. japonicum. Similarly rats vaccinated with u.v.-attenuated S. japonicum cercariae were not resistant to heterologous challenge. Thus irradiated vaccines are species-specific in both permissive and non-permissive hosts. (author)

Attrition of schistosomes in an irradiation-attenuated cercarial immunization model of Schistosoma mansoni

International Nuclear Information System (INIS)

Stek, M. Jr.; Dean, D.A.; Clark, S.S.

1981-01-01

The attrition of Schistosoma mansoni challenge worms was studied in irradiation-attenuated cercaria-immunized mice as a function of site and time. The peak recovery of schistosomula from the lungs of immunized mice was delayed 2 days in comparison with non-immunized controls. The difference between the peak recoveries of control and immunized mice accounted for about half of the final attrition observed at the 7-week adult worm stge. Hepatic-mesenteric vein worm recoveries obtained 10 to 42 days after challenge were reduced in most cases at least as much as the 49-day counts. Somewhat higher reductions were observed at 14 to 28 days than at 49 days, confirming the evidence of delayed migration obtained at the lung phase. These findings, coupled with histologic observations, indicate that at least half of the worm elimination attributable to immunization occurs 8 or more days after the challenge infection

THE MEDICALLY IMPORTANT MOLLUSCS OF INDONESIA

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Machfudz Djajasasmita

2012-09-01

Full Text Available At present in Indonesia 32 species of non-marine molluscs which belong to IS families have been known to be potentially of medicalor veterinary importance, since they are suspected to be capable in transmitting human and animal diseases. The brackish water family Potamididae comprises of 1 species; whereas the freshwater snails are : Viviparidae (3 sp., Ampullariidae (3 sp., Bythiniidae (1 sp.. Pomatiopsidae (1 sp., Thiaridae (7 sp., Lymnaeidae(l sp. and Planorbidae (5 sp.; freshwater bivalve are: Corbiculidae (4 sp.; land snails are: Subulinidae (2 sp., Achatinidae (1 sp. and Bradybaenidae (1 sp.; land slug: Veronicelidae (2 sp. Philomycidae (1 sp. and Limacidae (1 sp.. All are common species which can be found in the vicinity of human habitation (ponds, rice-field, ditches, gardens etc. The parasitological studies on these molluscs are rather limited, only 9 species have been studied and confirmed to be the intermediate host of parasitic nematodes and nematodes; i.e. Oncomelania hupensis lindoensis, the intermediate host of the blood fluke Schistosoma japonica in Central Sulawesi: Pila suctata, Achatina fulica and Laevicaulis alte from several places in Sumatra, Java, Sulawesi and Flores have been found to be harbouring the larvae of the nematode Angiostrongylus cantonensis, the causative agent of eosinophilic meningoencephalitis; Bellamy a rudipelis, Gyraulus sarasinorum and Corbicula lindoensis were recorded as the intermediate host of the intestinal fluke Echinostoma lindoensis in Central Sulawesi; Lymnaea rubiginosa plays an important role in the life-cycle of the cattle liver fluke Fasciola gigantica and F.hepatica, which may reduce the national meat production; and Digoniostoma truncatum from Bali has been recorded naturally infected with radiae and cercariae of Paramphistoma sp., the causative agent of the fatal paramphistomiasis of cattle. Gyraulus convexiusculus is considered to be the most likely first intermediate host of

Aspects of the granulomatous reaction in the liver of mice infected and reinfected with two different geographical strains of Schistosoma mansoni

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Pedro Raso

1994-12-01

Full Text Available In this study, which was undertaken in relation to the histopathologic behavior of two different strains (LE-Belo Horizonte, MG and SJ - São José dos Campos, SP in infections and reinfections (homologous or heterologous with Schistosoma mansoni, the authors confirmed a more accentuated pathogenicity of the SJ strain. All the reinfections showed the presence of typical granulomas of the acute phase, when performed either with the same strain (homologous or with a different strain (heterologous of the parasite of the primo infection. The possible mechanisms responsible for reactivation of the immunopathologic response in reinfections are discussed.No presente estudo, verificou-se o comportamento histopatológico das infecções e reinfecções, homólogas ou heterólogas, das cepas LE (Belo Horizonte, MG e SJ (São José dos Campos, SP de Schistosoma mansoni. Confirmou-se uma maior patogenicidade da cepa SJ de S. mansoni. As reinfecções, independentemente de terem sido feitas com a mesma cepa (homóloga ou cepa diferente da primo infecção (heteróloga do parasito, mostraram a presença de granulomas típicos da fase aguda. São discutidos os possíveis mecanismos responsáveis pela reagudização da resposta imunopatológica nas reinfecções.

Studies on the physiology and endocrinology of reproduction of Helisoma duryi (Mollusca: Pulmonata)

Energy Technology Data Exchange (ETDEWEB)

Miksys, S.L.

1987-01-01

Helisoma duryi is a hermaphroditic, freshwater, pulmonate snail native to North America. It has been proposed as a biological control agent against snail intermediate hosts of Schistosoma sp., a parasitic trematode in man. Very little is known of the physiology and endocrinology of reproduction of H. duryi. This thesis investigates vitello-genesis, endocrine control of the synthesis of albumen, a nutrient-rich fluid catabolized by developing embryos, and the possible endocrine role of the gonad. Light and electron microscopy, chemical extraction, energy dispersive X-ray analysis, and radioimmunoassay are used to identify the yolk protein ferritin. It is proposed that ferritin synthesis, and its circulating levels, are regulated, probably indirectly, by a gonadal factor released into the blood. The rate of synthesis of albumen polysaccharides can be monitored in vitro by providing albumen gland explants with the precursor /sup 14/C-glucose and measuring /sup 14/C-polysaccharide produced. The basal synthetic activity of the gland reflects the reproductive activity of the snail.

Comparative Phylogenetic Studies on Schistosoma japonicum and Its Snail Intermediate Host Oncomelania hupensis: Origins, Dispersal and Coevolution.

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Stephen W Attwood

Full Text Available Schistosoma japonicum causes major public health problems in China and the Philippines; this parasite, which is transmitted by freshwater snails of the species Oncomelania hupensis, causes the disease intestinal schistosomiasis in humans and cattle. Researchers working on Schistosoma in Africa have described the relationship between the parasites and their snail intermediate hosts as coevolved or even as an evolutionary arms race. In the present study this hypothesis of coevolution is evaluated for S. japonicum and O. hupensis. The origins and radiation of the snails and the parasite across China, and the taxonomic validity of the sub-species of O. hupensis, are also assessed.The findings provide no evidence for coevolution between S. japonicum and O. hupensis, and the phylogeographical analysis suggests a heterochronous radiation of the parasites and snails in response to different palaeogeographical and climatic triggers. The results are consistent with a hypothesis of East to West colonisation of China by Oncomelania with a re-invasion of Japan by O. hupensis from China. The Taiwan population of S. japonicum appears to be recently established in comparison with mainland Chinese populations.The snail and parasite populations of the western mountain region of China (Yunnan and Sichuan appear to have been isolated from Southeast Asian populations since the Pleistocene; this has implications for road and rail links being constructed in the region, which will breach biogeographical barriers between China and Southeast Asia. The results also have implications for the spread of S. japonicum. In the absence of coevolution, the parasite may more readily colonise new snail populations to which it is not locally adapted, or even new intermediate host species; this can facilitate its dispersal into new areas. Additional work is required to assess further the risk of spread of S. japonicum.

Follicular helper T cells promote liver pathology in mice during Schistosoma japonicum infection.

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Xiaojun Chen

2014-05-01

Full Text Available Following Schistosoma japonicum (S. japonicum infection, granulomatous responses are induced by parasite eggs trapped in host organs, particular in the liver, during the acute stage of disease. While excessive liver granulomatous responses can lead to more severe fibrosis and circulatory impairment in chronically infected host. However, the exact mechanism of hepatic granuloma formation has remained obscure. In this study, we for the first time showed that follicular helper T (Tfh cells are recruited to the liver to upregulate hepatic granuloma formation and liver injury in S. japonicum-infected mice, and identified a novel function of macrophages in Tfh cell induction. In addition, our results showed that the generation of Tfh cells driven by macrophages is dependent on cell-cell contact and the level of inducible costimulator ligand (ICOSL on macrophages which is regulated by CD40-CD40L signaling. Our findings uncovered a previously unappreciated role for Tfh cells in liver pathology caused by S. japonicum infection in mice.

Human antibody responses to Schistosoma mansoni: does antigen directed, isotype restriction result in the production of blocking antibodies?

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David W. Dunne

1987-01-01

Full Text Available After treatment young Kenyan schoolchildren are highly susceptible to reinfection with Schistosoma mansoni. Older children and adults are resistant to reinfection. There is no evidence that this age related resistance is due to a slow development of protective immunological mechanisms, rather, it appears that young children are susceptible because of the presence of blocking antibodies which decline with age, thus allowing the expression of protective responses. Correlations between antibody responses to different stages of the parasite life-cycle suggest that, in young children, antigen directed, isotype restriction of the response against cross-reactive polysaccharide egg antigens results in an ineffectual, or even blocking antibody response to the schistosomulum.

Resistência de Biomphalaria peregrina de Santa Rita do Sapucaí, Minas Gerais, a infecção com três cepas de Schistosoma mansoni Resistance of Biomphalaria peregrina from Santa Rita do Sapucaí, State of Minas Gerais, Brazil, to infection with strain of Schistosoma mansoni

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Cecília Pereira de Souza

1988-12-01

Full Text Available Descendentes do planorbídeo Biomphalaria peregrina, coletados em Santa Rita do Sapucaí, Minas Gerais, Brasil, foram expostos a miracídios de três cepas de Schistosoma mansoni: "LE" de Belo Horizonte, MG; "SJ" de São José dos Campos, SP e "AL" do Estado de Alagoas. Dentre 300 exemplares expostos, nenhum se infectou com as três cepas do trematódeo. Por outro lado, 300 exemplares de B. glabrata, dos grupos de controle, apresentaram taxas de infecção de 61,1 a 95,3% com as três cepas do trematódeo. As taxas de mortalidade de B. peregrina e de B. glabrata foram de 20,0 e de 28,0%, respectivamente.The descendants of the planorbid snail Biomphalaria peregrina, collected in the region of Santa rita do Sapucaí, Minas Gerais, Brazil, were exposed to miracidia of three strains of Schistosoma mansoni: "LE" strain from Belo Horizonte, State of Minas Gerais; "SJ", strain from São José dos Campos, State of São Paulo and "AL" strain from State of Alagoas. Of 300 snails exposed to miracidia of the three strains, none was infected. On the other hand, 300 Biomphalaria glabrata of the control groups showed infection rates of 61.1 to 95.3% with three strains. The mortality rates of B. peregrina and B. glabrata were 20% and 28%, respectively.

Immunization of mice with gamma-irradiated intramuscularly injected schistosomula of Schistosoma mansoni

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Bickle, Q.D.; Taylor, M.G.; Doenhoff, M.J.; Nelson, G.S.

1979-01-01

The parameters involved in the induction of resistance against Schistosoma mansoni by injection of irradiated, artificially transformed schistosomula were studied in mice. Single intramuscular injections of 500 schistosomula exposed to radiation doses in the range 2.3 to 160 krad. resulted in significant protection ( in the range 20 to 50% as assessed by reduced worm burdens) against a challenge infection administered at intervals from 3 to 24 weeks post-vaccination. However, schistosomular irradiated with 20 krad. consistently resulted in better protection than those exposed to either higher or lower radiation doses despite the persistence of stunted adults from the infections irradiated with 2.3 krad. Vaccination with 40 krad. schistosomula resulted in significant protection in terms of reduced worm and tissue egg burdens and increased survival following lethal challenge. Varying the number of irradiated schistosomula, the frequency and route of their administration, the site of challenge and the strain of host all failed to enhance the level of resistance. However, percutaneously applied, irradiated cercariae were found to be more effective in stimulating resistance (60%) than intramuscularly injected, irradiated schistosomula (40%). (author)

Comparison of ELISA, radioimmunoassay and stool examination for Schistosoma mansoni infection

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Long, E G [Ministry of Health, St. Lucia (West Indies); McLaren, M M; Goddard, M J [London School of Hygiene and Tropical Medicine (UK); Bartholomew, R K; Goodgame, R [Rockefeller Foundation, New York (USA); Peters, P [Case Western Reserve Univ., Cleveland, OH (USA)

1981-01-01

A comparison was made of the sensitivity and specificity of four diagnostic tests for Schistosoma mansoni infection in a community of 516 untreated persons in St. Lucia, West Indies. Prevalence of infection as obtained by: (i) the Bell filtration technique was 44.4% (one filter) and 63.2% (three filters); (ii) the Kato thick smear, 60.2%; (iii) by radioimmunoassay (RIA), using /sup 125/I, 73.3%; and (iv) enzyme-immunoassay (ELISA) 70.9%. The age distribution of persons serologically positive but parasitologically negative showed these to be mostly children and persons 40 years old and over. By means of a statistical test due to Cochrane it was concluded that there was no evidence to indicate a difference between paired serological tests and paired parasitological tests in their diagnostic capability. There was a very significant difference between the Bell technique and the other three tests. The ELISA emerged as a less satisfactory test than the RIA or the Kato thick smear. The levels of sensitivity and specificity of each test were measured by Armitage's ''J'' index. The reliability of the Bell filtration technique was 64%, of the ELISA 68%, of the RIA 78% and of the Kato 85%.

Lot quality assurance sampling for screening communities hyperendemic for Schistosoma mansoni.

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Rabarijaona, L P; Boisier, P; Ravaoalimalala, V E; Jeanne, I; Roux, J F; Jutand, M A; Salamon, R

2003-04-01

Lot quality assurance sampling (LQAS) was evaluated for rapid low cost identification of communities where Schistosoma mansoni infection was hyperendemic in southern Madagascar. In the study area, S. mansoni infection shows very focused and heterogeneous distribution requiring multifariousness of local surveys. One sampling plan was tested in the field with schoolchildren and several others were simulated in the laboratory. Randomization and stool specimen collection were performed by voluntary teachers under direct supervision of the study staff and no significant problem occurred. As expected from Receiver Operating Characteristic (ROC) curves, all sampling plans allowed correct identification of hyperendemic communities and of most of the hypoendemic ones. Frequent misclassifications occurred for communities with intermediate prevalence and the cheapest plans had very low specificity. The study confirmed that LQAS would be a valuable tool for large scale screening in a country with scarce financial and staff resources. Involving teachers, appeared to be quite feasible and should not lower the reliability of surveys. We recommend that the national schistosomiasis control programme systematically uses LQAS for identification of communities, provided that sample sizes are adapted to the specific epidemiological patterns of S. mansoni infection in the main regions.

Structural studies of Schistosoma mansoni adenylate kinases

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Marques, I.A.; Pereira, H.M.; Garrat, R.C.

2012-01-01

Full text: Parasitic diseases are a major cause of death in developing countries, however receive little or no attention from pharmaceutical companies for the development of novel therapies. In this respect, the Center for Structural Molecular Biology (CBME) of the Institute of Physics of Sao Carlos (IFSC / USP) has developed expertise in all stages of the development of active compounds against target enzymes from parasitic diseases. The present work focuses on the adenylate kinase enzymes (ADK's) from Schistosoma mansoni. These enzymes are widely distributed and catalyze the reaction of phosphoryl exchange between nucleotides in the reaction 2ADP to ATP + AMP, which is critical for the cells life cycle. Due to the particular property of the reaction catalyzed, the ADK's are recognized as reporters of the cells energetic state, translating small changes in the balance between ATP and ADP into a large change in concentration of AMP. The genome of S. mansoni was recently sequenced by the Sanger Center in England. On performing searches for genes encoding adenylate kinases we found two such genes. The corresponding gene products were named ADK1 (197 residues) and ADK2 (239 residues), and the two sequences share only 28 percent identity. Both have been cloned into the pET-28a(+)vector, expressed in E. coli and purified. Preliminary tests of activity have been performed only for ADK1 showing it to be catalytically active. Crystallization trials were performed for both proteins and thus far, crystals of ADK1 have been obtained which diffract to 2.05 at the LNLS beamline MX2 and the structure solved by molecular replacement. Understanding, at the atomic level, the function of these enzymes may help in the development of specific inhibitors and may provide tools for developing diagnostic tests for schistosomiasis. (author)

[Preservation of live eggs of Schistosoma japonicum].

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Lan, Wei-ming; Xie, Shu-ying; Wang, Qin; Jiang, Wei-sheng; Hu, Ren-mei; Ge, Jun; Zeng, Xiao-jun

2015-10-01

To observe the preservation time and activity of miracidium hatching from schistosome eggs preserved in different solutions, so as to obtain the optimal preservation conditions and then provide quality control products for field application. The rectum stool of rabbits infected with Schistosoma japonicum was collected and the coarse fecal residue was removed with a series of sample sieves of 80, 100, 160 and 200 meshes respectively, and then the schistosome eggs were concentrated with the sample sieve of 260 meshes. The concentrated eggs were preserved in 0.9% sodium chloride solution, 1.2% sodium chloride solution, phosphate buffered saline solution (PBS, PH 7.2), 1.0% sucrose solution, and Mili-Q water, respectively, and then were conserved in a 4 °C refrigerator and 15 °C constant temperature incubator, respectively. The preserved eggs were hatched in different time (7-day interval) , the vitality and quantity of the miracidia were observed, and the hatching rates were calculated. Under the condition of 4 °C, the hatching rates of eggs dropped to 0 in 1.0% sucrose solution and 1.2% sodium chloride solution at the 49th and 126th day, respectively, and the hatching rates of eggs in the 0.9% sodium chloride solution and PBS solution dropped to 10% at the 112th day, and the activity of miracidium was weakened since 140th. In the Mili-Q water, the hatching rate dropped less than 10% at the 196th day and the activity of miracidia was weakened since the 280th day. Under the condition of 15 °C, the hatching rate of eggs in different solutions gradually dropped to 0 from the 49th day to 105th day. The eggs preserved in Mili-Q water at the temperature of 4 °C can be used as the positive reference for hatching tests within 196 days.

Prevalence of gastrointestinal helminths in Mithun in Arunachal Pradesh

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S. Biswas

2014-10-01

Full Text Available Aim: The objective of this study was to know the prevalence of gastrointestinal (GI parasites in Mithun in Arunachal Pradesh. Materials and Methods: Approximately, 10 g of feces was collected from recently voided feces in airtight fecal collection vials (HiMedia, India. Fecal samples were subjected to the direct method and centrifuge flotation method for finding out parasitic ova. The ova were identified on the basis of morphological characters described by Soulsby, 1982. Result: A total of 78 fecal samples were collected. Of 78, 44 (56.41% samples were found positive. Most of the positive fecal sample showed mixed infection of different helminths parasites egg. Fasciola spp. and Amphistome spp. were the two predominant parasites among the flukes. In nematodes infection, Toxocara vitulorum was the least prevalent GI nematodes. In the case of cestodes Moniezia expansa was little higher (14% in semi-intensive. Conclusion: The present study reveals that Mithun is infected by several GI parasites. Among trematodes, Fasciola, and Amphistomes are predominantly spp. whereas, Strongyle and Trichuris are more prevalent spp. among nematodes and Moniezia among cestodes parasites.

Diversity of human intestinal helminthiasis in Lao PDR.

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Sayasone, Somphou; Vonghajack, Youthanavane; Vanmany, Monely; Rasphone, Oroth; Tesana, Smarn; Utzinger, Jürg; Akkhavong, Kongsap; Odermatt, Peter

2009-03-01

Food-borne trematodiasis is an emerging public health problem, including in Lao PDR. We investigated the diversity of intestinal helminthes and polyparasitism in patients with hepatobiliary or intestinal symptoms in hospital and community-based surveys. Stool samples from 232 individuals aged >or=15 years were examined by the Kato-Katz method (three samples) and a formalin ethyl-acetate concentration technique (one sample). Opisthorchis viverrini and minute intestinal flukes (MIF) were common, with prevalences of 86.2% and 62.9%, respectively. Hookworm was the predominant soil-transmitted helminth (65.9%). The prevalences of Taenia spp., Strongyloides stercoralis and Trichuris trichiura were 22.8%, 10.3% and 8.6%, respectively. Additionally, 97 individuals were purged; O. viverrini and Haplorchis taichui were found in 95 and 76 participants, respectively. Other trematodes included Phaneropsolus bonnei (22.7%), Prosthodendrium molenkampi (14.4%), Haplorchis pumilio (5.2%), Haplorchis yokogawai (3.1%) and Echinochasmus japonicus (3.1%). Co-infection with O. viverrini and MIFs was rampant (81.4%). Polytrematode infection is highly prevalent in Lao PDR and hence requires urgent attention.

Risk factors for Clonorchis sinensis infection transmission in humans in northern Vietnam: A descriptive and social network analysis study.

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Vinh, Hoang Quang; Phimpraphai, Waraphon; Tangkawattana, Sirikachorn; Smith, John F; Kaewkes, Sasithorn; Dung, Do Trung; Duong, Tran Thanh; Sripa, Banchob

2017-04-01

Clonorchis sinensis is major fish-borne trematode, endemic in North Vietnam. Risk factors described so far include individual eating behaviors and environmental factors. Here, additional to conventional risk factors, we report on socially influenced liver fluke transmission in endemic communities. A cross-sectional study on risk factors and fish sharing networks was conducted in 4 villages of Gia Thinh Commune, Ninh Binh Province. A total of 510 residents in 272 households were recruited for risk factor analysis while 220 households, 28 fishermen and 10 fish-sellers were enrolled for social network study. Fecal examination for C. sinensis eggs was performed. Average C. sinensis infection rate at Gia Thinh commune was 16.5% (range 2% to 34.4%). Higher infection rates were significantly associated with males, lower educational levels, eating raw fish, and location of the villages. Social network analysis (SNA) showed a strong positive correlation between ego network size (number of households in fish sharing network) and quantity of raw fish consumed (r=0.603, Psinensis infection transmission in northern Vietnam. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

In Vitro Assay of Paecilomyces lilacinus Biocontrol Effects on Fasciola hepatica Eggs Illustrated in Scanning Electron Micrographs

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Faezeh NAJAFI

2017-02-01

Full Text Available Background: Fascioliasis is a zoonotic disease caused by the liver fluke Fasciola hepatica. Drug resistance, high costs of treatment and economic losses in meat production have emerged the need of alternative control measures into consideration. The aim of this study was to evaluate the in vitro ovicidal activity of Paecilomyces lilacinus fungus on F. hepatica eggs. Methods: P. lilacinus isolated from the soil of natural environment was challenged on F. hepatica eggs to observe the bio control effect of nematophagous fungi on trematode helminth eggs. The study was conducted in Tehran University of Medical Sciences, in 2015. Within 21 d of experiment, destructive effects exhibited on the eggshells were investigated using optical and Scanning Electron Microscopy. Results: The effective role of P. lilacinus on damaging the eggs of F. hepatica was noticed. Conclusion: This finding is promising for advantageous use of nematophagus fungi as a natural constituent in hyper endemic areas for certain helminthic infections like fascioliasis with diverse kinds of herbivores as egg passer hosts.

Fasciola hepatica demonstrates high levels of genetic diversity, a lack of population structure and high gene flow: possible implications for drug resistance.

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Beesley, Nicola J; Williams, Diana J L; Paterson, Steve; Hodgkinson, Jane

2017-01-01

Fasciola hepatica, the liver fluke, is a trematode parasite of considerable economic importance to the livestock industry and is a re-emerging zoonosis that poses a risk to human health in F. hepatica-endemic areas worldwide. Drug resistance is a substantial threat to the current and future control of F. hepatica, yet little is known about how the biology of the parasite influences the development and spread of resistance. Given that F. hepatica can self-fertilise and therefore inbreed, there is the potential for greater population differentiation and an increased likelihood of recessive alleles, such as drug resistance genes, coming together. This could be compounded by clonal expansion within the snail intermediate host and aggregation of parasites of the same genotype on pasture. Alternatively, widespread movement of animals that typically occurs in the UK could promote high levels of gene flow and prevent population differentiation. We identified clonal parasites with identical multilocus genotypes in 61% of hosts. Despite this, 84% of 1579 adult parasites had unique multilocus genotypes, which supports high levels of genotypic diversity within F. hepatica populations. Our analyses indicate a selfing rate no greater than 2%, suggesting that this diversity is in part due to the propensity for F. hepatica to cross-fertilise. Finally, although we identified high genetic diversity within a given host, there was little evidence for differentiation between populations from different hosts, indicating a single panmictic population. This implies that, once those emerge, anthelmintic resistance genes have the potential to spread rapidly through liver fluke populations. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Schistosoma mansoni: migration potential of normal and radiation attenuated parasites in naive guinea pigs

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Kamiya, H.; McLaren, D.J.

1987-01-01

Compressed tissue autoradiography using [75Se]selenomethionine labelled parasites has been used to investigate the migration potential of normal and radiation attenuated cercariae of Schistosoma mansoni in naive guinea pigs. By Day 14 after infection. 44% of normal parasites were detected as reduced silver foci in the liver; this value corresponded well with the number of liver parasites recovered by retrograde perfusion of the hepatic portal system on Day 42 (42% of the challenge). In contrast, cercariae subjected to 50 krad of gamma irradiation failed to migrate out of the skin. The migration capacity of 20 krad irradiated parasites was less severely affected in that about half of the challenge parasites reached the lungs, but virtually none moved to the liver. These data are discussed in relation to the kinetics of immunity induced in guinea pigs by infection or vaccination with normal or radiation attenuated parasites

Schistosoma japonicum: An ultraviolet-attenuated cercarial vaccine applicable in the field for water buffaloes

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Shi, Y.E.; Jiang, C.F.; Han, J.J.; Li, Y.L.; Ruppel, A.

1990-01-01

Water buffaloes were vaccinated three times with 10,000 Schistosoma japonicum cercariae irradiated with ultraviolet (uv) light at a dose of 400 microW x min/cm2. The irradiation was performed with cheap, simple, and portable equipment in a rural area of Hubei Province (People's Republic of China). A challenge infection of 1000 untreated cercariae was given to six vaccinated and six naive control buffaloes, while two vaccinated animals were not challenged. The experiment was terminated 6 weeks after the challenge. Control animals had lost body weight and harbored a mean of 110 worms and 37 eggs per gram of liver. The vaccinated animals gained weight after the challenge and developed 89% resistance to infection with S. japonicum. Since schistosomiasis japonica is nowadays transmitted in China predominantly by domestic livestock, a uv-attenuated cercarial vaccine for bovines may contribute to the control of this disease

Molecular and morphological characterization of the cercariae of Lecithodendrium linstowi (Dollfus, 1931), a trematode of bats, and incrimination of the first intermediate snail host, Radix balthica.

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Enabulele, Egie E; Lawton, Scott P; Walker, Anthony J; Kirk, Ruth S

2018-03-01

Lecithodendrium linstowi is one of the most prevalent and abundant trematodes of bats, but the larval stages and intermediate hosts have not been identified. We present the first molecular and morphological characterization of the cercariae of L. linstowi based on a phylogenetic analysis of partial fragments of LSU and ITS2 rDNA. The first intermediate host was incriminated as Radix balthica by DNA barcoding using cox1 and ITS2 sequences, although the snail morphologically resembled Radix peregra, emphasizing the requirement for molecular identification of lymnaeids as important intermediate hosts of medical and veterinary impact. The application of molecular data in this study has enabled linkage of life cycle stages and accurate incrimination of the first intermediate host.

Neurological and ocular fascioliasis in humans.

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Mas-Coma, Santiago; Agramunt, Verónica H; Valero, María Adela

2014-01-01

Fascioliasis is a food-borne parasitic disease caused by the trematode species Fasciola hepatica, distributed worldwide, and Fasciola gigantica, restricted to given regions of Africa and Asia. This disease in humans shows an increasing importance, which relies on its recent widespread emergence related to climate and global changes and also on its pathogenicity in the invasive, biliary, and advanced chronic phases in the human endemic areas, mainly of developing countries. In spite of the large neurological affection capacity of Fasciola, this important pathogenic aspect of the disease has been pronouncedly overlooked in the past decades and has not even appear within the numerous reviews on the parasitic diseases of the central nervous system. The aim of this wide retrospective review is an in-depth analysis of the characteristics of neurological and ocular fascioliasis caused by these two fasciolid species. The terms of neurofascioliasis and ophthalmofascioliasis are restricted to cases in which the direct affection of the central nervous system or the eye by a migrant ectopic fasciolid fluke is demonstrated by an aetiological diagnosis of recovered flukes after surgery or spontaneous moving-out of the fluke through the orbit. Cases in which the ectopic fluke is not recovered and the symptoms cannot be explained by an indirect affection at distance may also be included in these terms. Neurofascioliasis and ophthalmofascioliasis cases are reviewed and discussed. With regard to fascioliasis infection giving an indirect rise to neurological affection, the distribution and frequency of cases are analysed according to geography, sex, and age. Minor symptoms and major manifestations are discussed. Three main types of cases are distinguished depending on the characteristics of their manifestations: genuine neurological, meningeal, and psychiatric or neuropsychic. The impressive symptoms and signs appearing in each type of these cases are included. Brain examination

Efeito do praziquantel incorporado a lipossomas nos diferentes estágios de desenvolvimento dos ovos de Schistosoma mansoni

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T. F. FREZZA

2009-01-01

Full Text Available

A esquistossomose mansônica é causada pelo trematódeo digenético intravascular Schistosoma mansoni. Para o tratamento dessa enfermidade o praziquantel (PZQ e a oxamniquina (OXA são os fármacos escolhidos. No entanto, esses fármacos apresentam limitações quanto à ação e casos de resistência ou tolerância já foram relatados. Por esse motivo, são necessários os estudos de novas alternativas que visam melhorar os fármacos já existentes, como a incorporação desses em lipossomas. Este estudo verificou a ação do praziquantel incorporado a lipossomas (lip.PZQ sobre os ovos de S. mansoni, linhagem BH em camundongos Mus musculus (Swiss- SPF. Para tanto, foram testadas quatro doses de PZQ e lip.PZQ (47; 60; 250 e 300mg/kg sendo que parte dos camundongos foi tratada após 30 dias de infecção e outra após 45 dias. A análise do oograma mostrou que a dose lip.PZQ 300mg/kg administrada no 45º dia de infecção foi mais eficaz, pois reduziu a oviposição pelas fêmeas de S. mansoni. Palavras-chave: Schistosoma mansoni; praziquantel; lipossoma; oograma.

Serological screening of the Schistosoma mansoni adult worm proteome.

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Fernanda Ludolf

2014-03-01

Full Text Available BACKGROUND: New interventions tools are a priority for schistosomiasis control and elimination, as the disease is still highly prevalent. The identification of proteins associated with active infection and protective immune response may constitute the basis for the development of a successful vaccine and could also indicate new diagnostic candidates. In this context, post-genomic technologies have been progressing, resulting in a more rational discovery of new biomarkers of resistance and antigens for diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: Two-dimensional electrophoresed Schistosoma mansoni adult worm protein extracts were probed with pooled sera of infected and non-infected (naturally resistant individuals from a S. mansoni endemic area. A total of 47 different immunoreactive proteins were identified by mass spectrometry. Although the different pooled sera shared most of the immunoreactive protein spots, nine protein spots reacted exclusively with the serum pool of infected individuals, which correspond to annexin, major egg antigen, troponin T, filamin, disulphide-isomerase ER-60 precursor, actin and reticulocalbin. One protein spot, corresponding to eukaryotic translation elongation factor, reacted exclusively with the pooled sera of non-infected individuals living in the endemic area. Western blotting of two selected recombinant proteins, major egg antigen and hemoglobinase, showed a similar recognition pattern of that of the native protein. CONCLUDING/SIGNIFICANCE: Using a serological proteome analysis, a group of antigens related to the different infection status of the endemic area residents was identified and may be related to susceptibility or resistance to infection.

Evidentiation of Paramyosin (Sm-97 as a Modulating Antigen on Granulomatous Hypersensitivity to Schistosoma mansoni Eggs

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Hirsch Cristine

1997-01-01

Full Text Available A Schistosoma mansoni adult worm anionic fraction (PIII has previously been shown to protect mice against challenge infection and to reduce pulmonary and hepatic granulomatous hypersensitivity. Serum from PIII-immunized rabbit was used to screen a lgt11 cDNA library from S. mansoni adult worm in order to identify antigens capable of modulating granulomatous hypersensitivity. We obtained four clones with 400 (Sm-III.11, 900 (Sm-III.16, 1100 (Sm-III.10 and 1300 (Sm-III.12 bp of length. All clone-specific antibodies were able to recognize most of the PIII components. The sequence analysis showed that these clones presented high homology with S. mansoni paramyosin (Sm-97. These findings ascribe a new function to this antigen with an important role in modulation of granulomatous hypersensitivity to S. mansoni eggs

Host density and competency determine the effects of host diversity on trematode parasite infection.

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Jeremy M Wojdak

Full Text Available Variation in host species composition can dramatically alter parasite transmission in natural communities. Whether diverse host communities dilute or amplify parasite transmission is thought to depend critically on species traits, particularly on how hosts affect each other's densities, and their relative competency as hosts. Here we studied a community of potential hosts and/or decoys (i.e. non-competent hosts for two trematode parasite species, Echinostoma trivolvis and Ribeiroia ondatrae, which commonly infect wildlife across North America. We manipulated the density of a focal host (green frog tadpoles, Rana clamitans, in concert with manipulating the diversity of alternative species, to simulate communities where alternative species either (1 replace the focal host species so that the total number of individuals remains constant (substitution or (2 add to total host density (addition. For E. trivolvis, we found that total parasite transmission remained roughly equal (or perhaps decreased slightly when alternative species replaced focal host individuals, but parasite transmission was higher when alternative species were added to a community without replacing focal host individuals. Given the alternative species were roughly equal in competency, these results are consistent with current theory. Remarkably, both total tadpole and per-capita tadpole infection intensity by E. trivolvis increased with increasing intraspecific host density. For R. ondatrae, alternative species did not function as effective decoys or hosts for parasite infective stages, and the diversity and density treatments did not produce clear changes in parasite transmission, although high tank to tank variation in R. ondatrae infection could have obscured patterns.

Course of Schistosoma mansoni infection in thymectomized rats

International Nuclear Information System (INIS)

Cioli, D.; Dennert, G.

1976-01-01

Inbred rats were thymectomized, irradiated, and reconstituted with T cell-free bone marrow cells. Thymectomized-reconstituted (B rats) and control rats were infected with Schistosoma mansoni cercariae and the number of worms recovered was determined at various times after infection. The extent of immunosuppression was assessed by two criteria: response to an injection of sheep erythrocytes; response to schistosome antigens. Humoral responses to worm antigens were completely suppressed in almost all instances and anti-sheep erythrocytes responses showed a more variable but always very definite depression in B rats. The number of worms in B rats was about 4 times higher than in control animals at 5 weeks and about 3 times higher at 6 weeks. In a different experiment, rats were perfused at 4, 6, and 9 weeks after infection and the number of worms was found to be consistently higher in B rats, by a factor of about 2 at 4 weeks to a factor of about 4 or 6 at subsequent times. Although B rats had more worms than controls even at 9 weeks, a slow drop in their worm burden was noticeable with time in both experiments. Moreover, the size of worms in B rats was smaller than in controls and even 9-week-old worms failed to develop to normal size and appearance and could not be shown to produce fertile eggs. These experiments show a definite involvement of the immune system in the ''self-cure'' phenomenon, but may at the same time suggest that other non-immune mechanisms are involved in determining the pattern of S. mansoni infection in the rat

Behavior of Schistosoma mansoni-induced histopathological lesions in Biomphalaria glabrata submitted to ionizing radiation

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Azevedo Carine M.

2004-01-01

Full Text Available Present report demonstrates that repeated radiation of Schistosoma mansoni-infected Biomphalaria glabrata, totaling 15,000 rads, caused a sudden, albeit transient, suppression of cercarial shedding. Initially, sporocysts practically disappeared from the snail tissues. The more resistant developing cercariae presented nuclear clumping and vacuolation, before undergoing lysis. No host tissue reaction was evident at any time. Thirty-four days after the last irradiation, the snails resumed cercarial elimination. By that time numerous sporocysts and developing cercariae were detected, disseminated throughout snail tissues in a pattern similar to that of a highly malignant neoplasm, with no signs of host cellular reactions, which on the other hand were present in non-irradiated infected controls. The region of the ovo-testis was apparently destroyed after radiation, but returned to its normal appearance around 40 days after the last radiation. Ionizing radiation affected both host and parasite in S. mansoni-infected Biomphalaria glabrata, but the resulting impressive changes were soon reversed.

Cross-species prophylactic efficacy of Sm-p80-based vaccine and intracellular localization of Sm-p80/Sm-p80 ortholog proteins during development in Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium.

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Molehin, Adebayo J; Sennoune, Souad R; Zhang, Weidong; Rojo, Juan U; Siddiqui, Arif J; Herrera, Karlie A; Johnson, Laura; Sudduth, Justin; May, Jordan; Siddiqui, Afzal A

2017-11-01

Schistosomiasis remains a major global health problem. Despite large-scale schistosomiasis control efforts, clear limitations such as possible emergence of drug resistance and reinfection rates highlight the need for an effective schistosomiasis vaccine. Schistosoma mansoni large subunit of calpain (Sm-p80)-based vaccine formulations have shown remarkable efficacy in protecting against S. mansoni challenge infections in mice and baboons. In this study, we evaluated the cross-species protective efficacy of Sm-p80 vaccine against S. japonicum and S. haematobium challenge infections in rodent models. We also elucidated the expression of Sm-p80 and Sm-p80 ortholog proteins in different developmental stages of S. mansoni, S. haematobium, and S. japonicum. Immunization with Sm-p80 vaccine reduced worm burden by 46.75% against S. japonicum challenge infection in mice. DNA prime/protein boost (1 + 1 dose administered on a single day) resulted in 26.95% reduction in worm burden in S. haematobium-hamster infection/challenge model. A balanced Th1 (IFN-γ, TNF-α, IL-2, and IL-12) and Th2 (IL-4, IgG1) type of responses were observed following vaccination in both S. japonicum and S. haematobium challenge trials and these are associated with the prophylactic efficacy of Sm-p80 vaccine. Immunohistochemistry demonstrated that Sm-p80/Sm-p80 ortholog proteins are expressed in different life cycle stages of the three major human species of schistosomes studied. The data presented in this study reinforce the potential of Sm-p80-based vaccine for both hepatic/intestinal and urogenital schistosomiasis occurring in different geographical areas of the world. Differential expression of Sm-p80/Sm-p80 protein orthologs in different life cycle makes this vaccine potentially useful in targeting different levels of infection, disease, and transmission.

Host cell adhesion to Schistosoma mansoni larvae in the peritoneal cavity of naive mice: histological and scanning electron microscopic studies Adesão celular às larvas de Schistosoma mansoni na cavidade peritoneal de camundongos normais: estudos histológicos e microscopia eletrônica de varredura

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Alan Lane de Melo

1993-02-01

Full Text Available Cercariae of Schistosoma mansoni inoculated into the peritoneal cavity of naive mice induced host cell adhesion to their surface, but after 90 minutes the number of adherent cells sharply decreased. The cell detachment is progressive and simultaneous to the cercaria-schistosomule transformation. The histological study showed mainly neutrophils in close contact with the larvae. Mononuclear cells and some eosinophils were occasionally seen surrounding the adherent neutrophils. The scanning electron microscopy showed cells displaying twisted microvilli and several microplicae contacting or spreading over the larval surface, and larvae completely surrounded by clusters of cells. These results suggest that the neutrophils recognize molecules on the cercarial surface which induce their spreadingA inoculação de cercárias de Schistosoma mansoni na cavidade peritoneal de camundongos normais induz uma aderência de células do hospedeiro a essas larvas. Essa adesão decresce rapidamente quando a larva infectante transforma-se em esquistossômulo. O destacamento das células é progressivo e simultâneo à transformação. Os métodos histológicos e a microscopia eletrônica de varredura mostraram que o neutrófilo é a célula predominante em estreito contacto com a larva. Células mononucleadas e eosinófilos foram observados rodeando o parasito, usualmente sem estar em contacto direto com a larva. Os resultados indicam que neutrófilos podem reconhecer, na superfície larvária, moléculas que induzem sua adesão e espalhamento.

The Compatibility Between Biomphalaria glabrata Snails and Schistosoma mansoni: An Increasingly Complex Puzzle.

Science.gov (United States)

Mitta, G; Gourbal, B; Grunau, C; Knight, M; Bridger, J M; Théron, A

2017-01-01

This review reexamines the results obtained in recent decades regarding the compatibility polymorphism between the snail, Biomphalaria glabrata, and the pathogen, Schistosoma mansoni, which is one of the agents responsible for human schistosomiasis. Some results point to the snail's resistance as explaining the incompatibility, while others support a "matching hypothesis" between the snail's immune receptors and the schistosome's antigens. We propose here that the two hypotheses are not exclusive, and that the compatible/incompatible status of a particular host/parasite couple probably reflects the balance of multiple molecular determinants that support one hypothesis or the other. Because these genes are involved in a coevolutionary arms race, we also propose that the underlying mechanisms can vary. Finally, some recent results show that environmental factors could influence compatibility. Together, these results make the compatibility between B. glabrata and S. mansoni an increasingly complex puzzle. We need to develop more integrative approaches in order to find targets that could potentially be manipulated to control the transmission of schistosomiasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ultrasound monitoring of structural urinary tract disease in Schistosoma haematobium infection

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King Charles H

2002-01-01

Full Text Available A major advance in our understanding of the natural history of Schistosoma haematobium-related morbidity has come through the introduction of the portable ultrasound machines for non-invasive examination of the kidneys and bladder. With the use of generators or battery packs to supply power in non-clinical field settings, and with the use of instant photography or miniaturized thermal printers to record permanent images, it is possible to examine scores of individuals in endemic communities every day. Broad-based ultrasound screening has allowed better definition of age-specific disease risks in urinary schistosomiasis. Results indicate that urinary tract abnormalities are common (18% overall prevalence in S. haematobium transmission areas, with a 2-4% risk of either severe bladder abnormality or advanced ureteral obstruction. In longitudinal surveys, ultrasound studies have shown that praziquantel and metrifonate therapy are rapidly effective in reversing urinary tract abnormalities among children. The benefits of treating adults are less well known, but research in progress should help to define this issue. Similarly, the prognosis of specific ultrasound findings needs to be clarified, and the ease of sonographic examination will make such long-term follow-up studies feasible. In summary, the painless, quick, and reproducible ultrasound examination has become an essential tool in the study of urinary schistosomiasis.

Oral Vaccination Based on DNA-Chitosan Nanoparticles against Schistosoma mansoni Infection

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Carolina R. Oliveira

2012-01-01

Full Text Available The development of a vaccine would be essential for the control of schistosomiasis, which is recognized as the most important human helminth infection in terms of morbidity and mortality. A new approach of oral vaccination with DNA-chitosan nanoparticles appears interesting because of their great stability and the ease of target accessibility, besides chitosan immunostimulatory properties. Here we described that chitosan nanoparticles loaded with plasmid DNA encoding Rho1-GTPase protein of Schistosoma mansoni, prepared at different molar ratios of primary amines to DNA phosphate anion (N/P, were able to complex electrostatically with DNA and condense it into positively charged nanostructures. Nanoparticles were able to maintain zeta potential and size characteristics in media that simulate gastric (SGF and intestinal fluids (SIF. Further in vivo studies showed that oral immunization was not able to induce high levels of specific antibodies but induced high levels of the modulatory cytokine IL-10. This resulted in a significative reduce of liver pathology, although it could not protect mice of infection challenge with S. mansoni worms. Mice immunized only with chitosan nanoparticles presented 47% of protection against parasite infection, suggesting an important role of chitosan in inducing a protective immune response against schistosomiasis, which will be more explored in further studies.

The growth and development of Schistosoma mansoni in mice exposed to sublethal doses of radiation

International Nuclear Information System (INIS)

Aitken, R.; Wilson, R.A.

1989-01-01

The maturation of Schistosoma mansoni was studied in mice exposed to various sublethal doses of radiation. Although the treatment of mice with 500 rads of radiation prior to infection did not alter parasite maturation, doses in excess of 500 rads led to a reduction in worm burden. This could not be attributed to a delay in the arrival of parasites in the hepatic portal system. Worms developing in mice treated with 800 rads commenced egg-laying about 1 wk later than worms in intact mice, and the rate of egg deposition appeared to be lower in irradiated hosts. The data demonstrate that exposure of C57BL/6 mice to doses of radiation in excess of 500 rads impairs their ability to carry infections of S. mansoni. The findings do not support the hypothesis that primary worm burdens in the mouse are controlled by a host immune response

Role of berberine in ameliorating Schistosoma mansoni-induced hepatic injury in mice

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Mohamed A Dkhi

2014-01-01

Full Text Available BACKGROUND: Schistosomiasis is caused by helminth parasites of the genus Schistosoma. Berberine chloride (BER, an isoquinoline alkaloid, has been used in vivo for its antiparasitic, antioxidant and hepatoprotective properties. In this study, the protective effect of BER and praziquantel has been compared for the extent of schistosomiasis-induced oxidative stress in hepatic tissue of mice. RESULTS: S. mansoni was able to induce inflammation and injury to the liver, evidenced (i by an increase in inflammatory cellular infiltrations, dilated sinusoids and vacuolated hepatocytes, (ii by decreased levels of alanine and aspartate aminotransferases and increased levels of alkaline phosphatase, γ-glutamyl transferase in the liver homogenate, (iii by increased production of nitric oxide and thiobarbituric acid reactive substances, and (iv by lowered glutathione levels and decreased activities of catalase and superoxide dismutase, respectively. All these infection-induced parameters were significantly altered during BER treatment. In particular, berberine counteracted the S. mansoni-induced loss of glutathione and the activities of catalase and superoxide dismutase. CONCLUSION: Based on these results, it is concluded that berberine could ameliorate pre-existing liver damage and oxidative stress conditions due to schistosomiasis.

Gene Gun Bombardment with DNA-Coated Golden Particles Enhanced the Protective Effect of a DNA Vaccine Based on Thioredoxin Glutathione Reductase of Schistosoma japonicum

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Yan Cao

2013-01-01

Full Text Available Schistosomiasis, caused by infection with Schistosoma species, remains an important parasitic zoonosis. Thioredoxin glutathione reductase of Schistosoma japonicum (SjTGR plays an important role in the development of the parasite and for its survival. Here we present a recombinant plasmid DNA vaccine, pVAX1/SjTGR, to estimate its protection against S. japonicum in BALB/c mice. The DNA vaccine administrated by particle bombardment induced higher protection than by intramuscular injection. All animals vaccinated with pVAX1/SjTGR developed significant specific anti-SjTGR antibodies than control groups. Moreover, animals immunized by gene gun exhibited a splenocyte proliferative response, with an increase in IFN-γ and IL-4. The recombinant plasmid administrated by gene gun achieved a medium protective efficacy of 27.83–38.83% ( of worm reduction and 40.38–44.51% ( of liver egg count reduction. It suggests that different modes of administering a DNA vaccine can influence the protective efficacy induced by the vaccine. Interestingly, from the enzymatic activity results, we found that worms obtained from pVAX1/SjTGR-vaccinated animals expressed lower enzymatic activity than the control group and the antibodies weakened the enzymatic activity of SjTGR in vitro, too. It implies that the high-level antibodies may contribute to the protective effects.

Antischistosomal activity of acridanone- hydrazones in Cebus monkeys experimentally infected with the SJ strain of Schistosoma mansoni

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Paulo Marcos Zech Coelho

1995-09-01

Full Text Available In this study, four compounds were utilized at the dose of 12.5mg/kg body weight, p.o., to treat Cebus monkeys experimentally infected with about 200 cercariae of Schistosoma mansoni (SJ strain, via transcutaneous route. The oograms performed with rectal snips, as well as stool examinations carried out periodically, showed no viable eggs of the parasite, from day 29 to 226post-treatment. The perfusion undertaken after killing the animals showed absence of worms in the treated monkeys, whereas 83 worms were recovered from the control, thus corroborating the results obtained by means of oograms and coproscopy. These results confirm the efficacy of 9-acridanone- hydrazones previously tested against the LE strain of S. mansoni. The low curative dose and apparent absence of toxicity render these dmgs an important therapeutic reserve, taking into consideration the reports on the resistance of S. mansoni to the modern drugs oxamniquine and praziquantel.No presente trabalho, quatro compostos foram utilizados na dose de 12,5mg/kg de peso, por via oral, em macacos infectados transcutaneamente com cerca de 200 cercárias de Schistosoma mansoni. Os oogramas realizados com fragmentos de mucosa retal e os exames de fezes realizados, periodicamente, demonstraram a ausência de ovos viáveis do parasito a partir do 29- até o 226a dia pós-tratamento. A perfusão, apôs sacrifício dos animais tratados, não detectou vermes, enquanto que do macaco cotztrole 83 vermes foram recuperados, confirmando assim os resultados dos oogramas e da coproscopia. Estes resultados confirmam a eficácia das 9-acridanonas- hydrazonas já observada anteriormente contra a cepa LE de S. mansoni. A baixa dosagem curativa e aparente ausência de toxicidade colocam estas drogas como uma reserva terapêutica importante, tendo em vista o relato de resistência do S. mansoni às drogas modernas oxamniquína e praziquantel.

The impact of iron supplementation on reinfection with intestinal helminths and Schistosoma mansoni in western Kenya

DEFF Research Database (Denmark)

Olsen, Annette; Nawiri, J; Friis, Henrik

2001-01-01

immune function or to unfavourable host gut conditions caused by an increased oxidative stress. In each case, the lack of effect in children remains to be explained. In contrast, iron supplementation apparently was short-lived in favour of hookworm infection, an effect that needs further clarification......A randomized, placebo-controlled, double-blind trial was carried out in 1994-96 among 231 children and 181 adults in order to determine the effects of iron on reinfection rates and intensities of hookworm, Ascaris lumbricoides, Trichuris trichiura and Schistosoma mansoni. Adults given 60 mg...... reinfection rates or intensities in children. Multiple logistic regression analyses controlling for baseline infection status confirmed the effect in adults of iron on A. lumbricoides, T. trichiura and S. mansoni reinfection rates. The effect is suggested to be due to reduced risk behaviour, to improved...

Hallazgos laparoscópicos en la infección por Schistosoma mansori. Estudio en 209 pacientes

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Fabio Rivas Muñoz

1988-12-01

Full Text Available Se describen los hallazgos laparoscópicos en 209 pacientes parasitados de Schistosoma mansoni, estudiados en el lnstituto de Medicina Tropical "PEDRO KOURI" (IPK de La Habana (Cuba entre 1979 y 1988. El diagnóstico de la enfermedad se hizo mediante análisis coproparasitológico, utilizando la técnica de Knigth. La laparoscopía, realizada de conformidad con el paciente, antes de instaurar el tratamiento, mostró la presencia de GRANULOMAS sobre la superficie hepática y ESPLENOMEGALIA como los hallazgos más prominentes. No se tiene conocimiento de reportes similares con este tipo de estudios y se plantea la posibilidad de que la laparoscopía se constituya en una herramienta importante en la valoración del grado de compromiso hepatoesplénico sufrido por quienes padecen la enfermedad.

Suppression of basophil histamine release and other IgE-dependent responses in childhood Schistosoma mansoni/hookworm coinfection

DEFF Research Database (Denmark)

Pinot de Moira, Angela; Fitzsimmons, Colin M; Jones, Frances M

2014-01-01

(HR), plus helminth- and HDM-specific IgE and IgG4 responses were measured pre- and post-treatment. RESULTS: Nonspecific- and helminth-specific-HR, and associations between helminth-specific IgE and helminth-specific HR increased post-treatment. Hookworm infection appeared to modify the relationship...... between circulating levels of HDM-IgE and HR: a significant positive association was observed among children without detectable hookworm infection, but no association was observed among infected children. In addition, hookworm infection was associated with a significantly reduced risk of wheeze, and IgG4...... in Ugandan schoolchildren coinfected with Schistosoma mansoni and hookworm. METHODS: Skin prick test (SPT) sensitivity to house dust mite allergen (HDM) and current wheeze were assessed pre-anthelmintic treatment. Nonspecific (anti-IgE), helminth-specific, and HDM-allergen-specific basophil histamine release...

Health implications of chronic hepatosplenomegaly in Kenyan school-aged children chronically exposed to malarial infections and Schistosoma mansoni

DEFF Research Database (Denmark)

Wilson, Shona; Vennervald, Birgitte J; Kadzo, Hilda

2010-01-01

Hepatosplenomegaly among school-aged children in sub-Saharan Africa is highly prevalent. Two of the more common aetiological agents of hepatosplenomegaly, namely chronic exposure to malaria and Schistosoma mansoni infection, can result in similar clinical presentation, with the liver and spleen...... being chronically enlarged and of a firm consistency. Where co-endemic, the two parasites are thought to synergistically exacerbate hepatosplenomegaly. Here, two potential health consequences, i.e. dilation of the portal vein (indicative of increased portal pressure) and stunting of growth, were...... with hepatosplenomegaly. Children who presented with hepatosplenomegaly had the lowest height-for-age Z-scores. This study shows that hepatosplenomegaly associated with chronic exposure to malaria and schistosomiasis is not a benign symptom amongst school-aged children but has potential long-term health consequences....

Ocorrência de linhagens humana e silvestre de Schistosoma mansoni, na pré-amazônia: I - estudo em moluscos Occurrence of wild and human strains of Schistosoma mansoni in lower Amazonia: I - study in moluscs

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Othon de Carvalho Bastos

1982-10-01

Full Text Available Foram isoladas na região da Baixada Maranhense (Brasil, linhagens humana (H e silvestre(S de Schistosoma mansoni a partir de miracídios eclodidos de ovos encontrados em fezes de doentes humanos autóctones da Região e de fígados de roedores silvestres naturalmente infectados. Biomphalaria glabrata, descentes de caramujos coletados no campo, foram expostos, isoladamente, aos miracídios H e S, mantidos isolados em moluscário e observados durante 100 dias. Moluscos normais foram mantidos nas mesmas condições de ambiente em que foram submetidos os infectados e tomados como controle da experiência. Foram anotados os indices de infecção dos moluscos, as datas da eliminação de cercárias, quantidade de larvas eliminadas e mortalidade dos moluscos. Os dados sugeriram melhor adaptação do esquistossomo da linhagem H à B. glabrata. A linhagem S, por sua vez, foi três vezes mais virulenta do que a linhagem H. Estes dados foram comparados com os encontrados na literatura especializada e verificado diversidades nos comportamentos parasitológicos das linhagens em estudo, quando comparados com os encontrados nas linhagens H e S oriundas do Vale do Rio Paraíba do Sul, no Estado de São Paulo (Brasil.The wild (W and human (H strains of Schistosoma mansoni were isolated in the Lowland Region of the Maranhão State (Brazil. The snail progenies from Biomphalaria glabrata collected from that region were exposed to the W miracidia, obtained from livers of wild rodents, and H miracidia from eggs in human stools. A control gruop of normal snails was kept in the same conditions as the infected one. The date of the elimination of cercariae, the quantity of eliminated larvae, the infection index of the moluscs and the mortality rate of the snails were recorded. These data suggested better adaptation of the H strain to B. glabrata. The W strain presented three times more virulence to snails than the H strain. These results were compared with published

TIMPs of parasitic helminths - a large-scale analysis of high-throughput sequence datasets.

Science.gov (United States)

Cantacessi, Cinzia; Hofmann, Andreas; Pickering, Darren; Navarro, Severine; Mitreva, Makedonka; Loukas, Alex

2013-05-30

Tissue inhibitors of metalloproteases (TIMPs) are a multifunctional family of proteins that orchestrate extracellular matrix turnover, tissue remodelling and other cellular processes. In parasitic helminths, such as hookworms, TIMPs have been proposed to play key roles in the host-parasite interplay, including invasion of and establishment in the vertebrate animal hosts. Currently, knowledge of helminth TIMPs is limited to a small number of studies on canine hookworms, whereas no information is available on the occurrence of TIMPs in other parasitic helminths causing neglected diseases. In the present study, we conducted a large-scale investigation of TIMP proteins of a range of neglected human parasites including the hookworm Necator americanus, the roundworm Ascaris suum, the liver flukes Clonorchis sinensis and Opisthorchis viverrini, as well as the schistosome blood flukes. This entailed mining available transcriptomic and/or genomic sequence datasets for the presence of homologues of known TIMPs, predicting secondary structures of defined protein sequences, systematic phylogenetic analyses and assessment of differential expression of genes encoding putative TIMPs in the developmental stages of A. suum, N. americanus and Schistosoma haematobium which infect the mammalian hosts. A total of 15 protein sequences with high homology to known eukaryotic TIMPs were predicted from the complement of sequence data available for parasitic helminths and subjected to in-depth bioinformatic analyses. Supported by the availability of gene manipulation technologies such as RNA interference and/or transgenesis, this work provides a basis for future functional explorations of helminth TIMPs and, in particular, of their role/s in fundamental biological pathways linked to long-term establishment in the vertebrate hosts, with a view towards the development of novel approaches for the control of neglected helminthiases.

Characterization of a novel organic solute transporter homologue from Clonorchis sinensis.

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Yanyan Lu

2018-04-01

Full Text Available Clonorchis sinensis is a liver fluke that can dwell in the bile ducts of mammals. Bile acid transporters function to maintain the homeostasis of bile acids in C. sinensis, as they induce physiological changes or have harmful effects on C. sinensis survival. The organic solute transporter (OST transports mainly bile acid and belongs to the SLC51 subfamily of solute carrier transporters. OST plays a critical role in the recirculation of bile acids in higher animals. In this study, we cloned full-length cDNA of the 480-amino acid OST from C. sinensis (CsOST. Genomic analysis revealed 11 exons and nine introns. The CsOST protein had a 'Solute_trans_a' domain with 67% homology to Schistosoma japonicum OST. For further analysis, the CsOST protein sequence was split into the ordered domain (CsOST-N at the N-terminus and disordered domain (CsOST-C at the C-terminus. The tertiary structure of each domain was built using a threading-based method and determined by manual comparison. In a phylogenetic tree, the CsOST-N domain belonged to the OSTα and CsOST-C to the OSTβ clade. These two domains were more highly conserved with the OST α- and β-subunits at the structure level than at sequence level. These findings suggested that CsOST comprised the OST α- and β-subunits. CsOST was localized in the oral and ventral suckers and in the mesenchymal tissues abundant around the intestine, vitelline glands, uterus, and testes. This study provides fundamental data for the further understanding of homologues in other flukes.

Characterization of a novel organic solute transporter homologue from Clonorchis sinensis

Science.gov (United States)

Dai, Fuhong; Lee, Ji-Yun; Pak, Jhang Ho; Sohn, Woon-Mok

2018-01-01

Clonorchis sinensis is a liver fluke that can dwell in the bile ducts of mammals. Bile acid transporters function to maintain the homeostasis of bile acids in C. sinensis, as they induce physiological changes or have harmful effects on C. sinensis survival. The organic solute transporter (OST) transports mainly bile acid and belongs to the SLC51 subfamily of solute carrier transporters. OST plays a critical role in the recirculation of bile acids in higher animals. In this study, we cloned full-length cDNA of the 480-amino acid OST from C. sinensis (CsOST). Genomic analysis revealed 11 exons and nine introns. The CsOST protein had a ‘Solute_trans_a’ domain with 67% homology to Schistosoma japonicum OST. For further analysis, the CsOST protein sequence was split into the ordered domain (CsOST-N) at the N-terminus and disordered domain (CsOST-C) at the C-terminus. The tertiary structure of each domain was built using a threading-based method and determined by manual comparison. In a phylogenetic tree, the CsOST-N domain belonged to the OSTα and CsOST-C to the OSTβ clade. These two domains were more highly conserved with the OST α- and β-subunits at the structure level than at sequence level. These findings suggested that CsOST comprised the OST α- and β-subunits. CsOST was localized in the oral and ventral suckers and in the mesenchymal tissues abundant around the intestine, vitelline glands, uterus, and testes. This study provides fundamental data for the further understanding of homologues in other flukes. PMID:29702646

Schistosoma mansoni: aspectos quantitativos da evolução de cercarias irradiadas a nível da pele, pulmões e sistema porta, em camundongos Schistosoma mansoni: quantitative aspects of the evolution of gamma-irradiated cercariae at the skin, lungs, and portal system, in mice

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Gileno de Sá Cardoso

1989-10-01

Full Text Available Foi estudada a migração do Schistosoma mansoni (cepas LE e SJ em oito grupos de camundongos albinos (Mus musculus não isogênicos, infectados transcutaneamente com cerca de 450 cercarias não irradiadas (grupos controles e irradiadas com 3 Krad, 20 Krad e 40 Krad de radiação gama proveniente de cobalto-60, Na pele, observou-se uma diminuição progressiva das taxas de recuperação em função do tempo e, nos pulmões e sistema porta, verificou-se uma relação inversa significativa entre as taxas de recuperação total e as doses de irradiação. A dose de 20 Krad praticamente impede a migração dos parasites, de ambas as cepas, dos pulmões até o sistema porta, enquanto a de 40 Krad praticamente impede a migração dos mesmos da pele para os pulmões.The migration of Schistosoma mansoni (LE and SJ strains has been studied in eight groups of outbred Swiss albino mice (Mus musculus, which were previously infected with ca 450 cercariae, transcutaneously. The infection of mice was performed with non irradiated cercariae (control groups, or with gamma-irradiated cercariae, at the schedule of 3, 20 and 40 Krad. Regarding the skin, a progressive decrease was detected for the recovery rates, related to the time of infection. As far as the lungs and portal system are concerned, a significant inverse correlation was observed between the total recovery rate and the irradiation dosages. The dose of 20 Krad practically hinders the migration of the parasites (in both strains from the lungs to the portal system, whereas the dose of 40 Krad prevents the migration of most of the parasites from the skin to the lungs.

Estudo da potencialidade de populações de Biomphalaria straminea do Estado de Minas Gerais, como hospedeiras do Schistosoma mansoni Potentiality of the Biomphalaria straminea populations of the State of Minas Gerais, as hosts of Schistosoma mansoni

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Cecília Pereira de Souza

1983-09-01

Full Text Available Caramujos de Biomphalaria straminea, descendentes de exemplares coletados em nove municípios do Estado de Minas Gerais, foram infectados experimentalmente com três cepas de Schistosoma mansoni: "LE", procedente de Belo Horizonte (MG; "SJ", procedente de São José dos Campos (SP e "AL" procedente do Nordeste (AL. As taxas de infeção variaram de 0,0 a 24,0% com a cepa "LE"; de 0,0 a 16% com a cepa "SJ" e de 2,0 a 9,0% com a cepa "AL". Os índices de infecção experimental obtidos foram semelhantes aos registrados por outros autores, para B. straminea dessa região. Comparou-se o número de cercárias de cepa "LE", eliminadas por oito exemplares de B. straminea de Baldim e oito Biomphalaria glabrata do controle, após 30 minutos de exposição à luz. O número de cercárias eliminadas por B. straminea foi de 4.550, aproximadamente cinco vezes menor que o de B. glabrata, 22.679. Discute-se a potencialidade desses moluscos como hospedeiros do S. mansoni nessa região.The decendents of Biomphalaria straminea snails collected in nine regions from the State of Minas Gerais were experimentally infected with three strains of Schistosoma mansoni: "LE", from Belo Horizonte, Minas Gerais; "SJ", from São José dos Campos, State of São Paulo and "AL", from State of Alagoas. The infection rates obtained were of 0 to 24% (LE strain, 0 to 16% (SJ strain and 2 to 9% (AL strain. These infection rates were similar to those obtained by other authors for B. straminea from this region. Comparation were made between the numbers of cercariae (LE strain shed by eight specimens of B. straminea from Baldim and eight B. glabrata of the control group, after 30 minutes of exposure to light. B. straminea shed 4,550 cercariae, about five times less than B. glabrata (22,679. The authors discuss the potentiality of theses molluscs as hosts of S. mansoni in this region.

Effects of Snail Density on Growth, Reproduction and Survival of Biomphalaria alexandrina Exposed to Schistosoma mansoni

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T. D. Mangal

2010-01-01

Full Text Available The effects of snail density on Biomphalaria alexandrina parasitized with Schistosoma mansoni were investigated. Laboratory experiments were used to quantify the impact of high density on snail growth, fecundity, and survival. Density-dependent birth rates of snails were determined to inform mathematical models, which, until now, have assumed a linear relationship between density and fecundity. The experiments show that the rate of egg-laying followed a negative exponential distribution with increasing density and this was significantly affected by exposure to parasitic infection. High density also affected the weight of snails and survival to a greater degree than exposure to parasitic infection. Although snail growth rates were initially constrained by high density, they retained the potential for growth suggesting a reversible density-dependent mechanism. These experimental data can be used to parameterise models and confirm that snail populations are regulated by nonlinear density-dependent mechanisms.

Protection against heterologous infection by using cross antigenicity between schistosoma mansoni and fasciola hepatica

International Nuclear Information System (INIS)

Moawad, M.A.; Amin, M.M.

2004-01-01

Fasciola hepatica is the causative agent of fasciolosis in many areas in America, Europe, Africa, Asia and Australia. There is an urgent need for improved methods to control the parasite's transmission. The present study is parasitological, immunological (interleukine-1β and interleukine-6) and histopathological investigations on the immunizing effect of cross antigenicity between S. mansoni and F. hepatica against schistosomiasis and fasciolosis in mice. Parasitological study showed that vaccination with irradiated cercariae of S. mansoni or vaccination by F. hepatica whole worm extract (FhWWE) before challenged with encysted metacercariae of F. hepatica or cercariae of S. mansoni played a significant control on the parasitic infection manifested by a remarkable reduction in the means of worm count. Assessment of IL-1β and IL-6 in sera of the experimental groups showed that there are cross reactivity between fasciola / schistosoma and its relation to cross protection. Histopathological examination of vaccinated mice livers showed protection against parasite maturation and liver damage after challenged, as compared to mice infected only without vaccination

The extracellular release of Schistosoma mansoni HMGB1 nuclear protein is mediated by acetylation

International Nuclear Information System (INIS)

Coutinho Carneiro, Vitor; Moraes Maciel, Renata de; Caetano de Abreu da Silva, Isabel; Furtado Madeira da Costa, Rodrigo; Neto Paiva, Claudia; Torres Bozza, Marcelo; Rosado Fantappie, Marcelo

2009-01-01

Schistosoma mansoni HMGB1 (SmHMGB1) was revealed to be a substrate for the parasite histone acetyltransferases SmGCN5 and SmCBP1. We found that full-length SmHMGB1, as well as its HMG-box B (but not HMG-box A) were acetylated in vitro by SmGCN5 and SmCBP1. However, SmCBP1 was able to acetylate both substrates more efficiently than SmGCN5. Interestingly, the removal of the C-terminal acidic tail of SmHMGB1 (SmHMGB1ΔC) resulted in increased acetylation of the protein. We showed by mammalian cell transfection assays that SmHMGB1 and SmHMGB1ΔC were transported from the nucleus to the cytoplasm after sodium butyrate (NaB) treatment. Importantly, after NaB treatment, SmHMGB1 was also present outside the cell. Together, our data suggest that acetylation of SmHMGB1 plays a role in cellular trafficking, culminating with its secretion to the extracellular milieu. The possible role of SmHMGB1 acetylation in the pathogenesis of schistosomiasis is discussed.

The extracellular release of Schistosoma mansoni HMGB1 nuclear protein is mediated by acetylation

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Coutinho Carneiro, Vitor; Moraes Maciel, Renata de; Caetano de Abreu da Silva, Isabel; Furtado Madeira da Costa, Rodrigo [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Neto Paiva, Claudia; Torres Bozza, Marcelo [Departamento de Imunologia, Instituto de Microbiologia Professor Paulo de Goes, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil); Rosado Fantappie, Marcelo, E-mail: fantappie@bioqmed.ufrj.br [Instituto de Bioquimica Medica, Programa de Biotecnologia e Biologia Molecular, Universidade Federal do Rio de Janeiro, CCS, Ilha do Fundao, Rio de Janeiro 21941-590 (Brazil)

2009-12-25

Schistosoma mansoni HMGB1 (SmHMGB1) was revealed to be a substrate for the parasite histone acetyltransferases SmGCN5 and SmCBP1. We found that full-length SmHMGB1, as well as its HMG-box B (but not HMG-box A) were acetylated in vitro by SmGCN5 and SmCBP1. However, SmCBP1 was able to acetylate both substrates more efficiently than SmGCN5. Interestingly, the removal of the C-terminal acidic tail of SmHMGB1 (SmHMGB1{Delta}C) resulted in increased acetylation of the protein. We showed by mammalian cell transfection assays that SmHMGB1 and SmHMGB1{Delta}C were transported from the nucleus to the cytoplasm after sodium butyrate (NaB) treatment. Importantly, after NaB treatment, SmHMGB1 was also present outside the cell. Together, our data suggest that acetylation of SmHMGB1 plays a role in cellular trafficking, culminating with its secretion to the extracellular milieu. The possible role of SmHMGB1 acetylation in the pathogenesis of schistosomiasis is discussed.

La queratotaxia cercariana en la diferenciacion de sexos de schistosoma mansoni

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Luz Arelis Pino

1988-09-01

Full Text Available El número de papilas argirófilas superficiales y su modelo de disposición en el tegumento de las cercarias (quetotaxia de Schistosoma mansoni nos permitió diferenciar los sexos a nivel del mencionado estadío larvario, mediante los siguientes critérios: - Mayor homogeneidad en las cercarias machos, en cuanto al número total de papilas ventrales y dorsales a nivel de cuerpo y cola cercarianos (C.V. = 4,1%, que en las cercarias hembras (C. V. = 18,3% (P < 0,001. - Presencia en el 80% de las cercarias machos de cuatro papilas en los cuadrantes "C" ó "D" inferior-izquierdo e inferior-derecho, respectivamente ventrales, mientras que dicho caracter sólo está presente en el 40% de las cercarias hembras (P < 0,001. - Diferencia estadísticamente significativa (P < 0,001 entre el número total promedio de papilas corporales centrales de las cercarias hembras (X = 11,9 ± 0,2 y el de las cercarias machos (X = 11,1 ± 0,3. - Diferencia estadísticamente significativa (P < 0,05 para la mayor distancia promedio entre las papilas AIL y AIIL, de cada cercaria, en relación con el sexo (femenino = 25,5 µm ± 0,33; masculino = 27,3 µm ± 0,26.

The mitochondrial genome of Paramphistomum cervi (Digenea, the first representative for the family Paramphistomidae.

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Hong-Bin Yan

Full Text Available We determined the complete mitochondrial DNA (mtDNA sequence of a fluke, Paramphistomum cervi (Digenea: Paramphistomidae. This genome (14,014 bp is slightly larger than that of Clonorchis sinensis (13,875 bp, but smaller than those of other digenean species. The mt genome of P. cervi contains 12 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions (NCRs, a complement consistent with those of other digeneans. The arrangement of protein-coding and ribosomal RNA genes in the P. cervi mitochondrial genome is identical to that of other digeneans except for a group of Schistosoma species that exhibit a derived arrangement. The positions of some transfer RNA genes differ. Bayesian phylogenetic analyses, based on concatenated nucleotide sequences and amino-acid sequences of the 12 protein-coding genes, placed P. cervi within the Order Plagiorchiida, but relationships depicted within that order were not quite as expected from previous studies. The complete mtDNA sequence of P. cervi provides important genetic markers for diagnostics, ecological and evolutionary studies of digeneans.

Evaluation of Protection against Schistosoma mansoni Infection in Mice Vaccinated with Irradiated Cercariae

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Amin, M.M.

2009-01-01

The Present study was designed to evaluate the biological changes in mice vaccinated with irradiated Schistosoma mansoni cercariae (40 krad) in comparison with infected non-vaccinated group. The degree of resistance was assessed by parasitological, biochemical, immunological, histopathological as well as scanning electron microscopy studies. The results of the present study revealed a significant reduction in worm burden and ova count in both liver and intestine of the immunized group. In addition, a moderate amelioration was recorded in the liver functions; gamma glutamyltransferase (gamma-GT), alkaline phosphatase (ALP), alanine and aspartate transaminase (ALT and AST). Assessment of tissue nuclear factor-a (TNF-a) and Interleukin -10 (IL-IO) in sera of the experimental groups showed significant protection changes. Histopathological examination of vaccinated mice livers showed protection against parasite maturation and liver damage after challenged as compared to mice infected only without vaccination. Also, scanning electron microscopy of whole worm revealed severe degree of surface tegumental disruption and intensive stunted of the worms as well as loss of the dorsal tegumental spines, On the other hand, there were severe deformations in both the anterior and ventral suckers as a result of the immunization

Therapeutic Effects of Allium sativum and Allium cepa in Schistosoma mansoni experimental infection

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Mona Mohamed Mantawy

2011-06-01

Full Text Available The effects of both garlic (Allium sativum and onion (Allium cepa on some biochemical parameters in Schistosoma mansoni infected mice individually and mixed either with or without the currently used drug, praziquantel (PZQ were investigated. These involved some immunological parameters, namely IgM, IgG, interleukins 2 and 6 (IL-2 and 6 and tumor necrosis factor (TNF-α, some antioxidant enzymes [catalase, superoxide dismutase (SOD and glutathione peroxidase (GPX]. In addition, parasitological and histopathological investigations were performed. No changes were observed in the normal control mice treated with dry extract of onion or garlic, individually or mixed, with or without PZQ, compared to the normal healthy control group. Infection with S. mansoni showed an increase in IgG, IgM, IL-2, IL-6, TNF-α and catalase enzyme, accompanied with a decrease in GPX and SOD antioxidant enzyme activities. Remarkable amelioration was noticed in the levels of all the measured parameters in S. mansoni infected mice after administration of the studied extracts. Moreover a significant reduction in worm burden, hepatic and intestinal eggs and oogram count was noticed which was reflected in normalization of liver architecture.

Carcinogenesis associated with parasites other than Schistosoma, Opisthorchis and Clonorchis: A systematic review.

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Machicado, Claudia; Marcos, Luis A

2016-06-15

Only three helminths (Schistosoma haematobium, Opisthorchis viverrini and Clonorchis sinensis) are directly associated with carcinogenesis in humans whereas the role of other parasites in cancer remains unclear. This study aimed to perform a systematic review to identify recent insights in the role of other parasite infections in carcinogenesis. We conducted systematic searches of MEDLINE and EMBASE on July 2015. Our primary outcome was the association between parasitic infections and carcinogenesis. Out of 1,266 studies, 19 were selected for detailed evaluation (eight for helminths and 11 for protozoa). The mechanisms of helminth-induced cancer included chronic inflammation, sustained proliferation, modulation of the host immune system, reprogramming of glucose metabolism and redox signaling, induction of genomic instability and destabilization of suppressor tumor proteins, stimulation of angiogenesis, resisting cell death, and activation of invasion and metastasis. In addition to the current knowledge, the following parasites were found in cancers or tumors: Echinococcus, Strongyloides, Fasciola, Heterakis, Platynosomum and Trichuris. Additional parasites were found in this systematic review that could potentially be associated with cancers or tumors but further evidence is needed to elaborate a cause-effect relationship. © 2016 UICC.

Genetic variability and identification of the intermediate snail hosts of Schistosoma mansoni

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Teofânia HDA Vidigal

1998-01-01

Full Text Available Studies based on shell or reproductive organ morphology and genetic considerations suggest extensive intraspecific variation in Biomphalaria snails. The high variability at the morphological and genetic levels, as well as the small size of some specimens and similarities between species complicate the correct identification of these snails. Here we review our work using methods based on polymerase chain reaction (PCR amplification for analysis of genetic variation and identification of Biomphalaria snails from Brazil, Argentina, Uruguay and Paraguay. Arbitrarily primed-PCR revealed that the genome of B. glabrata exihibits a remarkable degree of intraespecific polymorphism. Low stringency-PCR using primers for 18S rRNA permited the identification of B. glabrata, B. tenagophila and B. occidentalis. The study of individuals obtained from geographically distinct populations exhibits significant intraspecific DNA polymorphism, however specimens from the same species, exhibit some species specific LSPs. We also showed that PCR-restriction fragment of length polymorphism of the internal transcribed spacer region of Biomphalaria rDNA, using DdeI permits the differentiation of the three intermediate hosts of Schistosoma mansoni. The molecular biological techniques used in our studies are very useful for the generation of new knowledge concerning the systematics and population genetics of Biomphalaria snails.

Studies on chemotherapy of parasitic helminths (VI) effects of various neuropharmacological agents on the motility of Dipylidium caninum.

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Terada, M; Ishii, A I; Kino, H; Sano, M

1982-06-01

Effects of various neuropharmacological agents on the motility of Dipylidium caninum was studied. 5-HT stimulated the motility of D. caninum, while other drugs such as GABA, adrenaline, phenylephrine, isoproterenol, dibenamine, and propranolol showed little effect. The stimulatory action of 5-HT was antagonized by tryptophol. Stibnal caused paralysis which was blocked by the pretreatment with 5-HT. Paralytic effects were caused by eserine, dichlorovos, ACh, carbachol and DMPP, but not by pilocarpine and McN-A-343. d-Tubocurarine, hexamethonium, and atropine all showed little effect on the motility and on the paralytic action of eserine. Though guanidine showed little effect, strychnine remarkably stimulated the motility. The action of strychnine was stimulated by 5-HT but partially inhibited by tryptophol. Morphine and picrate slightly stimulated the motility, but showed little influence on the paralytic action of eserine. These two agents stimulated the paralyzed preparation by tryptophol transiently and sustainedly, respectively. These results on the cholinergic and serotonergic drugs basically showed good agreement with those reported in trematodes such as Schistosoma mansoni and Fasciola hepatica.

Eye-flukes in fish, living in cooling water from nuclear power plants

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Hoeglund, J.; Thulin, J.

1988-01-01

We report here on the effects of raised water temperature on the prevalence, mean infrapopulation density and consequences of eye-flukes in fish. The study was mainly performed in the Biotest basin situated 120 km north of Stockholm, Sweden. This 1 km 2 basin is an enclosed brackish water (5 permillage) area receiving heated (about 8 degree C) cooling water (90 m 3 /s) from Forsmark nuclear power station. Both morphological and experimental studies of the parasite larvae of sampled fish indicate that we are dealing with four strains of Diplostomum, two of which occur in perch and the other two in roach. Since taxonomic revisions are under hand elsewhere we prefer to name these strains Diplostomum sp1-4. Metacercariae of D.sp 1 were found between the retina and sclera in the eye of perch while that of D.sp 4 were found in the eye-lens of roach in over 90 % of fish examined. Metacercariae of the other two D.-species and of Tylodelphys clavata and Cotylurus sp were found at lower frequencies. Cercariae of Diplostomum spp were found to develop from sporocysts in snails of the genus Lymnaea. The period of cercarial shedding starts about one month earlier and is also prolonged in the Biotest basin compared to the reference locality. The infection procedure, however, is the same in both areas. During experimental infections with cercariae on yearlings of bleak we found a distinct correlation between an increased fry mortality and an increased cercariae density, a connection which was strengthened at increased water temperature. Furthermore, the results indicate that the defence mechanisms of the fish respond slower towards infections with Diplostomum spp than that is known to be the case with bacterial infections. The speed with which the metacercariae accumulate in the eye of the fish is higher in the Biotest basin than in the reference locality. In spite of this, the mean infrapopulation density of metacercariae in older fish is not higher here than in the reference

Suscetibilidade de Biomphalaria tenagophila do Estado de São Paulo à infecção por linhagens de Schistosoma mansoni da Baixada Maranhense (Maranhão, Brasil Susceptibility of Biomphalaria tenagophila, from S. Paulo State, to infection by Schistosoma mansoni, from the State of Maranhão

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Othon de Carvalho Bastos

1984-10-01

Full Text Available Exemplares de Biomphalaria tenagophila, provenientes do Vale do Rio Paraíba do Sul (São Paulo, Brasil, foram expostos às linhagens humana (H e silvestre (S de Schistosoma mansoni, oriundos da Região da Baixada Maranhense, ao noroeste do Estado do Maranhão. As linhagens H e S apresentaram comportamento distinto quando colocadas à infectar os moluscos paulistas. As B. tenagophila infectadas com a linhagem S apresentaram índice de mortalidade inferior ao observado nas infectadas com a linhagem H. No molusco paulista a linhagem silvestre maranhense completou seu desenvolvimento, fato que não ocorreu com a linhagem humana. Estas observações foram comparadas com os resultados anteriormente obtidos, quando estudou-se o comportamento das linhagens H e S do Vale do Rio Paraíba do Sul no molusco simpátrico. Foi verificado que as linhagens maranhenses e paulistas quando comparadas apresentavam comportamento similar frente a B. tenogophila do Vale do Rio Paraíba do Sul, SP.Wild (W and human (H strains of Schistosoma mansoni were isolated in the lowland region of Maranhão State (northeastern Brazil. Snail progenies of Biomphalaria tenagophila collected from Paraiba do Sul River valley (Southeastern Brazil were exposed to W miracidia, obtained from livers of wild rodents,and to H miracidia, from eggs in human stools. The date of elimination of cercariae, the quantity of eliminated larvae, the infection index of the moluscs and the mortality rate of the snails were recorded. This data suggest better adaptation of the W strain than of the H strain to B. tenagophila. These results were compared with published data of H and W strains from the Paraiba do Sul River valley and similar parasitological behavior was found.

Clonorchis sinensis ova in bile juice cytology from a patient with severe hyperbilirubinemia and portal vein thrombosis.

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Fujiya, Keiichi; Ganno, Hideaki; Ando, Masayuki; Chong, Ja-Mun

2016-03-01

Infection with the trematode Clonorchis sinensis is the most common human fluke infection in East Asian populations. Although this infection is associated with obstructive jaundice or choledocholithiasis, portal vein thrombosis has not been reported. Here, we report the first case of a 60-year-old man who had both C. sinensis infection and portal vein thrombosis with severe hyperbilirubinemia (75.4 mg/dl). He initially presented with abdominal pain and jaundice. Computed tomography revealed gallstones, common bile duct calculus, and thrombus in the left main branch of the portal vein. A nasobiliary tube was inserted under endoscopic retrograde cholangiography. Cytology of the bile juice revealed many C. sinensis eggs. The abdominal pain and jaundice improved following choledocholithotomy and combination treatment with a chemotherapeutic agent and anti-coagulant. This case suggests that inflammation around the portal vein as a result of C. sinensis infection has the potential to evoke portal vein thrombosis. Such cases should be treated with both a chemotherapeutic agent and anti-coagulant therapy. In conclusion, the possibility of infection with C. sinensis should be considered in patients presenting with hyperbilirubinemia and portal vein thrombosis, particularly in East Asian populations. © 2015 Wiley Periodicals, Inc.

Estudo de uma cepa humana de Schistosoma mansoni resistente a agentes esquistossomicidas

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Naftale Katz

1973-12-01

Full Text Available Foi isolada uma cepa de Schistosoma mansoni proveniente de dois pacientes tratados com hycanthone, por duas vezes, na dose de 2,5mg/kg, i.m., em janeiro e em abril de 1970, e com niridazole (25mg/kg dia x 5 oral, em abril de 1971. O número de ovos por grama de fezes nestes pacientes antes do tratamento era de 2675 e 1025, respectivamente e, após o terceiro tratamento, em torno de 100 ovos/g. Miracídios obtidos das fezes destes pacientes, infectaram caramujos (Biomphalaria glabrata, que passaram a eliminar cercárias (cepa WW. Estas foram utilizadas para infecção experimental de camundongos albinos. Os animais infectados foram tratados com esquemas múltiplos de hycanthone, niridazole e oxamniquine. Estudos comparativos das cepas WW e LE (esta última mantida rotineiramente em nossos laboratórios mostraram diferenças acentuadas quando à sensibilidade aos esquistossomicidas usados. De fato, com hycanthone, na dose de 80mg/kg, i.m. houve 100% de alteração do oograma nos camundongos infectados com a cepa L.E. e de 0,0% nos infectados com a cepa WW. Com a oxamniquine e niridazole as diferenças foram menores, mas, ainda assim, suficientes para indicar maior resistência da cepa WW a estes esquistossomicidas. Esta é a primeira vez na literatura, que se demonstra resistência em cepas de S. mansoni provenientes de pacientes tratados.There has been isolated a Schistosoma mansoni strain from two patients submitted to two courses of treatment with hycanthone (2,5mg/kg, i.m., in January and April, 1970, and to one course with niridazole (25mg/kg/day x 5, per os, in April, 1971. Before treatment, the number of eggs in the faeces of those patients was, per gram, 2,675 and 1,025, respectively; after completion of treatment, such number had come down to around 100 eggs/gram. Miracidia hatched from the patients faeces could infect Biomphalaria glabrata snails, which elimmated cercariae (WW strain that were used for experimental infection of albino

Potencialidade de Biomphalaria tenagophila do lago Pampulha, Belo Horizonte, MG, como hospederia do Schistosoma mansoni Potentiality of Biomphalaria tenagophila from Pampulha lake, Belo Horizonte, Minas Gerais State, as a host of Schistosoma mansoni

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Cecília Pereira de Souza

1987-03-01

Full Text Available Caramujos Biomphalaria tenagophila descendentes de exemplares coletados no lago da Pampulha, Belo Horizonte, Minas Gerais, foram expostos a miracídios de quatro cepas de Schistosoma mansoni: LE e HK de origem local, Belo Horizonte, AL do Estado de Alagoas e SJ, de São José dos Campos, SP. As cepas LE, AL e SJ são mantidas em laboratório e HK foi obtida de fezes de paciente que reside próximo à Pampulha. As taxas de infecção experimental foram de 4% (LE, 6% (HK, 30% (SJ e 40% (AL. Esses indícios de infecção foram semelhantes aos obtidos por vários autores para populações de B. tenagophila de Minas Gerais. Caramujos infectados experimentalmente eliminaram número de cercárias comparável ao de B. glabrata do controle e de B. tenagophila capturada no lago, com infecção natural (cerca de 2.000 cercárias/molusco. Devido à alta densidade planorbídica atual em alguns pontos do lago, número de cercárias eliminadas por exemplares naturalmente infectados, afluxo de pessoas para pesca e lazer, contaminação das águas por dejetos humanos, os autores alertam para o risco de crescimento do foco de esquistossomose no local.Biomphalaria tenagophila snails, from a population originally obtained from "Pampulha" lake, Belo Horizonte, Minas Gerais State, Brazil, were exposed to miracidia from four strains of Schistosoma mansoni: "LE" and "HK" from Belo Horizonte, "AL" from alagoas and "SJ" from São José dos Campos, São Paulo. The "LE", "AL" and "SJ" strains are maintained in the laboratory and the "HK" strain was obtained from feces of a patient residing near to "Pampulha" lake. Infection rates were of 4% ("LE" strain, 6% ("HK" strain, 30% ("SJ" strain and 40% ("AL" strain. These infection rates were similar to those obtained by others authors for B. tenagophila from Minas Gerais. Experimentally infected snails when compared to B. glabrata of the control group and B. tenagophila naturally infected in "Pampulha" lake shed similar number

Evaluation of a Mobile Phone-Based Microscope for Screening of Schistosoma haematobium Infection in Rural Ghana.

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Bogoch, Isaac I; Koydemir, Hatice C; Tseng, Derek; Ephraim, Richard K D; Duah, Evans; Tee, Joseph; Andrews, Jason R; Ozcan, Aydogan

2017-06-01

AbstractSchistosomiasis affects over 170 million people in Africa. Here we compare a novel, low-cost mobile phone microscope to a conventional light microscope for the label-free diagnosis of Schistosoma haematobium infections in a rural Ghanaian school setting. We tested the performance of our handheld microscope using 60 slides that were randomly chosen from an ongoing epidemiologic study in school-aged children. The mobile phone microscope had a sensitivity of 72.1% (95% confidence interval [CI]: 56.1-84.2), specificity of 100% (95% CI: 75.9-100), positive predictive value of 100% (95% CI: 86.3-100), and a negative predictive value of 57.1% (95% CI: 37.4-75.0). With its modest sensitivity and high specificity, this handheld and cost-effective mobile phone-based microscope is a stepping-stone toward developing a powerful tool in clinical and public health settings where there is limited access to conventional laboratory diagnostic support.

Natural infection of trematodes in Lymnaea (Radix) auricularia rubiginosa in water reservoirs in Amphoe Muang, Khon Kaen Province.

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Charoenchai, A; Tesana, S; Pholpark, M

1997-01-01

Lymnaea (Radix) auricularia rubiginosa (Michelin, 1831) was surveyed in 54 reservoirs of 18 districts in Amphoe Muang, Khon Kaen Province during February to May 1994. Lymnaeid snails were found in the water of 20 reservoirs, of which 16 reservoirs contained clear water and 4 turbid water. Two of the four turbid water reservoirs received drainage water from Khon Kaen Town. Two thousand four hundred and eight L. auricularia rubiginosa were collected and examined by shedding and crushing. Trematode infection occurred in 163 (6.77%) of 2,408 L. auricularia rubiginosa and some snails were infected with more than one cercarial species. Ninety-nine snails (4.11%) were infected with echinostomes, while mixed infection of echinostomes with Fasciola gigantica and with schistosomes was found in 5 snails (0.21%) and 2 snails (0.08%), respectively. Only 1 snail (0.04%), 19 snails (0.79%) and 37 snails (1.54%) were infected with F. gigantica, schistosomes and unidentified species, respectively. The mean size of infected snails was 6.89 +/- 2.02 mm (6.20-22.36) while the mean of sampled snails was 13.46 +/- 3.64 mm (4.00-26.55). The water plants which were found in reservoirs and presented with snails, were creeping water primose (Jusstaea repens), water lily (Nymphaea sp), water hyacinths (Eichornia crassipes) and grass.

First report of neurotoxic effect of the cyanobacterium Cylindrospermopsis raciborskii on the motility of trematode metacercariae.

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Lopes, K C; Ferrão-Filho, A S; Santos, E G N; Santos, C P

2018-03-01

Cylindrospermopsis raciborskii (Woloszynska) is a photosynthetic cyanobacterium that can produce cytotoxic (cylindrospermopsin) and neurotoxic cyanotoxins (saxitoxins). In Brazil the strains of C. raciborskii are reported to produce only saxitoxins (STX) and their effect on fish parasites has not been tested to date. The fish Poecilia vivipara Bloch and Schneider is a common host for the trematode Pygidiopsis macrostomum Travassos off the coast of Rio de Janeiro, and this fish-parasite interaction is a model for behavioural and ecotoxicological studies. The aim of this work was to evaluate the motility of metacercariae of P. macrostomum from P. vivipara exposed to 40 mg l-1 and 400 mg l-1 of crude lyophilized extract of the cyanobacterium C. raciborskii (CYRF-01) for 48 h. The fish were separated into groups of ten individuals and, after exposure, five fish from each group were dissected for counting and checking the motility of metacercariae. The other five fish were dissected after 48 h in clean water. The detection and quantification of STX in the solutions of cyanobacteria, and the gills and guts of fish, were performed by an enzyme-linked immunosorbent assay. The crude extract of C. raciborskii caused temporary paralysis in metacercariae of P. macrostomum after exposure of fish to both concentrations, and the motility recovered after the fish were kept for 48 h in clean water. STX was detected in the guts and gills of all fish analysed, suggesting that this toxin is involved in the paralysis of metacercariae. This is the first report on the action of neurotoxins in metacercariae of fish.

Evaluating diagnostic indicators of urogenital Schistosoma haematobium infection in young women: A cross sectional study in rural South Africa.

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Hashini Nilushika Galappaththi-Arachchige

Full Text Available Urine microscopy is the standard diagnostic method for urogenital S. haematobium infection. However, this may lead to under-diagnosis of urogenital schistosomiasis, as the disease may present itself with genital symptoms in the absence of ova in the urine. Currently there is no single reliable and affordable diagnostic method to diagnose the full spectrum of urogenital S. haematobium infection. In this study we explore the classic indicators in the diagnosis of urogenital S. haematobium infection, with focus on young women.In a cross-sectional study of 1237 sexually active young women in rural South Africa, we assessed four diagnostic indicators of urogenital S. haematobium infection: microscopy of urine, polymerase chain reaction (PCR of cervicovaginal lavage (CVL, urogenital symptoms, and sandy patches detected clinically in combination with computerised image analysis of photocolposcopic images. We estimated the accuracy of these diagnostic indicators through the following analyses: 1 cross tabulation (assumed empirical gold standard of the tests against the combined findings of sandy patches and/or computerized image analysis and 2 a latent class model of the four indicators without assuming any gold standard.The empirical approach showed that urine microscopy had a sensitivity of 34.7% and specificity of 75.2% while the latent class analysis approach (LCA suggested a sensitivity of 81.0% and specificity of 85.6%. The empirical approach and LCA showed that Schistosoma PCR in CVL had low sensitivity (14.1% and 52.4%, respectively and high specificity (93.0% and 98.0, respectively. Using LCA, the presence of sandy patches showed a sensitivity of 81.6 and specificity of 42.4%. The empirical approach and LCA showed that urogenital symptoms had a high sensitivity (89.4% and 100.0%, respectively, whereas specificity was low (10.6% and 12.3%, respectively.All the diagnostic indicators used in the study had limited accuracy. Using urine microscopy