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Kaethe Willms - One of the best experts on this subject based on the ideXlab platform.
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The key steroidogenic enzyme 3β-hydroxysteroid dehydrogenase in Taenia solium and Taenia crassiceps (WFU)
Parasitology Research, 2008Co-Authors: Ana María Fernández Presas, Kaethe Willms, Ricardo A. Valdez, Marta C. RomanoAbstract:Larval and adult stages of Taenia solium and Taenia crassiceps WFU strain were analyzed by histochemical and biochemical methods to determine the existence of steroid pathways. The presence of the key enzyme 3β-hydroxisteroid-dehydrogenase (3β-HSD) was examined in frozen sections of cysticerci obtained from mice and segments of Tapeworms obtained from the intestine of hamsters. 3β-HSD activity was detected by nitroblue-tetrazolium products after incubation with dehydroepiandrosterone, androstendiol, or pregnenolone. Tapeworm tissues exhibited 3β-HSD activity in the subtegumentary areas of the neck and immature proglottids following incubation with androstendiol, as well as surrounding the testes in mature proglottids. T. solium cysticerci exhibited 3β-HSD activity in the subtegumentary tissues. The synthesis of steroid hormones involving the activity of 3β-HSD was studied in cysticerci or Tapeworms incubated in the presence of tritiated steroid precursors. The culture media were analyzed by thin layer chromatography and showed synthesis of androstendiol, testosterone, and 17β-estradiol by cysticerci, androstendiol, and 17β-estradiol by Tapeworms. The results strongly suggest the activity of 3β-HSD in taeniid parasites that have at least a part of the enzymatic chain required for androgen and estrogen synthesis and that the enzymes are present in the larval stage and from the early strobilar stages to the mature proglottids.
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Morphology and biochemistry of the pork Tapeworm, Taenia solium.
Current Topics in Medicinal Chemistry, 2008Co-Authors: Kaethe WillmsAbstract:: This chapter describes the life cycle, general morphology and ultrastructure of the larval and adult stages of Taenia solium, a parasitic flatworm of humans found in underdeveloped countries. Experimental results describing the role of proteins and glycoproteins in the host-parasite relationship, as well as the various strategies the larval stage has developed to evade the host immune responses are analyzed. Characteristics of the Tapeworm attachment site in the hamster intestine and the host inflammatory reaction are reviewed. The general morphology and ultrastructure of the experimental Tapeworm is described, with emphasis on muscle fiber distribution, the abundance of cytoplasmic glycogen and its association with gap junctions, the development of testis, structure of mature spermatids and vas efferens. Recent descriptions of T. solium actin, myosin and calreticulin components, metabolic steroid pathways, apoptosis and glucose uptake of Tapeworms in the hamster model are reviewed.
Hector H Garcia - One of the best experts on this subject based on the ideXlab platform.
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genetic variability of taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers
PLOS Neglected Tropical Diseases, 2017Co-Authors: Monica Pajuelo, Hector H Garcia, Cesar M Gavidia, Maria Eguiluz, Elisa Roncal, Stefany Quinonesgarcia, Steven J Clipman, Juan Calcina, Patricia Sheen, Robert H GilmanAbstract:The adult Taenia solium, the pork Tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult Tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different Tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3%) out of 39 cysts originated from one Tapeworm, and 27 (100%) out of 27 cysts from the other had exactly the same genotype as the parental Tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult Tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental Tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified Tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared parental genotype.
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diphyllobothrium pacificum infection is seldom associated with megaloblastic anemia
American Journal of Tropical Medicine and Hygiene, 2012Co-Authors: Juan A Jimenez, Ricardo Gamboa, Silvia Rodriguez, Lourdes Rodriguez, Hector H GarciaAbstract:Twenty cases of Dyphillobothrium pacificum (fish Tapeworm) infections were prospectively studied to determine whether this Tapeworm is associated with megaloblastic anemia, as commonly reported for D. latum infections. The most frequent symptoms were fatigue and mild abdominal pain, which were identified in approximately 66.6% of the 18 patients interviewed. Fourteen patients received treatment with niclosamide and all were cured. The other six patients spontaneously eliminated the Tapeworms. One patient, who also had chronic diabetes and gastric atrophy, had low vitamin B12 levels and megaloblastic anemia. In all other patients, including three other patients with anemia, baseline vitamin B12 levels were in the reference range and did not significantly change when re-assessed three months later. Unlike D. latum, infection with D. pacificum is seldom associated with megaloblastic anemia or vitamin B12 deficit.
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swine cysticercosis hotspots surrounding taenia solium Tapeworm carriers
American Journal of Tropical Medicine and Hygiene, 2007Co-Authors: Andres G Lescano, Silvia Rodriguez, Hector H Garcia, Robert H Gilman, Victor C W Tsang, Claudia M Guezala, Cesar M Gavidia, Lawrence H MoultonAbstract:We estimated the Taenia solium swine cysticercosis risk gradient surrounding Tapeworm carriers in seven rural communities in Peru. At baseline, the prevalences of taeniasis by microscopy and swine cysticercosis by serology were 1.2% (11 of 898) and 30.8% (280 of 908), respectively. The four-month cumulative seroincidence was 9.8% (30 of 307). The unadjusted swine seroprevalence and seroincidence rates increased exponentially by 12.0% (95% confidence [CI] = 9.7-14.3%) and 32.8% (95% CI = 25.0-41.0%), respectively when distance to carriers decreased by half. Swine seroprevalence was 18.4% at > 500 meters from a carrier, 36.5% between 51 and 500 meters, and 68.9% within 50 meters (P < 0.001). Swine seroincidence also displayed a strong gradient near Tapeworm carriers (3.8%, 12.2%, and 44.0%; P < 0.001). Within 50 meters, swine seroprevalence appeared unaffected if the owners harbored Tapeworms, although pigs owned by a Tapeworm carrier had a four times higher seroincidence compared with other pigs (P = 0.005). In rural areas, swine cysticercosis occurs in high-risk hotspots around carriers where control interventions could be delivered.
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development of a serologic assay to detect taenia solium taeniasis
American Journal of Tropical Medicine and Hygiene, 1999Co-Authors: Patricia P Wilkins, Hector H Garcia, Armando E Gonzalez, Robert H Gilman, J C Allan, Manuela Verastegui, Mariela Acosta, Adam G Eason, Victor C W TsangAbstract:We developed a serologic assay to identify adult Taenia solium Tapeworm carriers using excretory/secretory (TSES) antigens collected from in vitro cultured T. solium Tapeworms. To identify taeniasis-specific antigens we used an immunoblot assay with serum samples from T. solium Tapeworm carriers and cysticercosis patients. Antigens were identified that reacted with antibodies present in serum samples from taeniasis cases and not with those from cysticercosis patients. Using serum samples collected from persons with confirmed T. solium Tapeworm infections, the test was determined to be 95% (69 of 73) sensitive. Serum samples (n = 193) from persons with other parasitic infections, including T. saginata Tapeworm infections, do not contain cross-reacting antibodies to TSES, indicating that the assay is 100% specific. These data suggest that the immunoblot assay using TSES antigens can be used to identify persons with current or recent T. solium Tapeworm infections and provides a new, important tool for epidemiologic purposes, including control and prevention strategies.
Eric P Hoberg - One of the best experts on this subject based on the ideXlab platform.
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definitive hosts of versteria Tapeworms cestoda taeniidae causing fatal infection in north america
Emerging Infectious Diseases, 2016Co-Authors: Roberta S Wallace, Annette Gendronfitzpatrick, Samuel D Sibley, Margot Stuchin, Michael Lauck, Antti Lavikainen, David H Oconnor, Minoru Nakao, Victoria L. Clyde, Eric P HobergAbstract:We previously reported fatal infection of a captive Bornean orangutan with metacestodes of a novel taeniid Tapeworm, Versteria sp. New data implicate mustelids as definitive hosts of these Tapeworms in North America. At least 2 parasite genetic lineages circulate in North America, representing separate introductions from Eurasia.
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genetics of the pig Tapeworm in madagascar reveal a history of human dispersal and colonization
PLOS ONE, 2014Co-Authors: Tetsuya Yanagida, Eric P Hoberg, Minoru Nakao, Yasuhito Sako, Jeanfrancois Carod, Akira ItoAbstract:An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig Tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the Tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single Tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation.
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Systematics of the Eucestoda: advances toward a new phylogenetic paradigm, and observations on the early diversification of Tapeworms and vertebrates
Systematic Parasitology, 1999Co-Authors: Eric P HobergAbstract:Evolutionary relationships of the Eucestoda have received intense but sporadic attention over the past century. Since 1996, the landscape has dramatically changed with respect to our knowledge of the phylogenetic relationships among the Tapeworms. The 2nd International Workshop for Tapeworm Systematics (IWTS) held in Lincoln, Nebraska in October of that year provided the catalyst for development of novel hypotheses for inter- and intra-ordinal phylogeny. The working-group structure of the 2nd IWTS and results of phylogenetic studies are briefly introduced in the present manuscript. Higher-level phylogenies derived from parsimony analysis of independent data bases representing comparative morphology or molecular sequences were largely congruent and supported monophyly for the Eucestoda. The Caryophyllidea are basal; difossate forms such as the Pseudophyllidea are primitive; tetrafossates including the Tetraphyllidea, Proteocephalidea, Nippotaeniidea, Tetrabothriidea and Cyclophyllidea are derived; and hypotheses differed in the placement of the Trypanorhyncha and the Diphyllidea. These studies may provide a foundation for resolution of inter- and intra-ordinal relationships for the Tapeworms. Additionally, the first comprehensive phylogenetic hypotheses for the Pseudophyllidea, Diphyllidea, Trypanorhyncha, the paraphyletic Tetraphyllidea + Lecanicephalidea, Proteocephalidea and Cyclophyllidea were developed during and subsequent to the 2nd IWTS. The stage is now set for continued and rapid advances in our understanding of the eucestodes. These studies have also served to re-emphasise the rich genealogical diversity of Tapeworms and the temporally deep history for their origin. A co-evolutionary history and radiation of eucestodes may involve deep co-speciation with vertebrate host taxa, accompanied by some level of colonisation and extinction, extending into the Palaeozoic, minimally 350-420 million years ago.
Galosi Livio - One of the best experts on this subject based on the ideXlab platform.
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Severe Tapeworm infestation and associated histopatological lesions in a Purple-throated Carib (Eulampis jugularis)
EAZWV ECZM LEIBNIZ-IZW, 2019Co-Authors: Rossi Giacomo, Turba, Maria Elena, Perrucci Stefania, Pesaro Stefano, Berardi Sara, Beraldo Paola, Biancani Barbara, Galosi LivioAbstract:The Purple-throated Carib (Eulampis jugularis) is an endemic hummingbird of the Lesser Antilles. Very few data are available on diseases of this bird. A wild-caught female Purple-throated Carib, kept in an Italian scientific center, was presented for necropsy after death. Although gross lesions were not observed, a large number of Tapeworms showing an unarmed scolex was evidenced in the small intestine. Histologically, this severe Tapeworm infestation was associated with severe mucosal hyperplasia, submucosal gland proliferation and severe lymphoid follicular hyperplasia, especially in the duodenum. Consequent to the strong thickening of the intestinal mucosa, areas of intestinal sub-obstruction, where the hyperplastic mucosa filled the entire duodenal cross-section, were evidenced. Based on parasite and egg morphology and PCR analysis, the isolated unarmed Tapeworm species was identified as belonging to the family Hymenolepididae. Although Tapeworm infestations have been reported in hummingbirds (Widmer et al., 2013), no data on prevalence of Hymenolepididae infestations in captive or free-ranging birds are available and no associated lesions have been described in previous studies. This report is the first description of pathological lesions and death associated with Tapeworm infection in an hummingbird
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Severe Tapeworm infestation associated with histopathological lesions in a purple-throated carib (Eulampis jugularis)
2019Co-Authors: Rossi Giacomo, Perrucci Stefania, Pesaro Stefano, Beraldo Paola, Me. Turba, Berardi S., Biancani B., Galosi LivioAbstract:The Purple-throated Carib (Eulampis jugularis) is an endemic hummingbird of the Lesser Antilles. Very few data are available on diseases of this bird. A wild-caught female Purple-throated Carib, kept in an Italian scientific center, was presented for necropsy after death. Although gross lesions were not observed, a large number of Tapeworms showing an unarmed scolex was evidenced in the small intestine. Histologically, this severe Tapeworm infestation was associated with severe mucosal hyperplasia, submucosal gland proliferation and severe lymphoid follicular hyperplasia, especially in the duodenum. Consequent to the strong thickening of the intestinal mucosa, areas of intestinal sub-obstruction, where the hyperplastic mucosa filled the entire duodenal cross-section, were evidenced. Based on parasite and egg morphology and PCR analysis, the isolated unarmed Tapeworm species was identified as belonging to the family Hymenolepididae. Although Tapeworm infestations have been reported in hummingbirds (Widmer et al., 2013), no data of prevalence of infestation in captive breed or wild birds are available and no associated lesions have been described in previous studies in this or in other species. This report is the first description of pathological lesions inducing death, caused by Tapeworms, in an Hummingbird
Robert H Gilman - One of the best experts on this subject based on the ideXlab platform.
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genetic variability of taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers
PLOS Neglected Tropical Diseases, 2017Co-Authors: Monica Pajuelo, Hector H Garcia, Cesar M Gavidia, Maria Eguiluz, Elisa Roncal, Stefany Quinonesgarcia, Steven J Clipman, Juan Calcina, Patricia Sheen, Robert H GilmanAbstract:The adult Taenia solium, the pork Tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult Tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different Tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3%) out of 39 cysts originated from one Tapeworm, and 27 (100%) out of 27 cysts from the other had exactly the same genotype as the parental Tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult Tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental Tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified Tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared parental genotype.
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swine cysticercosis hotspots surrounding taenia solium Tapeworm carriers
American Journal of Tropical Medicine and Hygiene, 2007Co-Authors: Andres G Lescano, Silvia Rodriguez, Hector H Garcia, Robert H Gilman, Victor C W Tsang, Claudia M Guezala, Cesar M Gavidia, Lawrence H MoultonAbstract:We estimated the Taenia solium swine cysticercosis risk gradient surrounding Tapeworm carriers in seven rural communities in Peru. At baseline, the prevalences of taeniasis by microscopy and swine cysticercosis by serology were 1.2% (11 of 898) and 30.8% (280 of 908), respectively. The four-month cumulative seroincidence was 9.8% (30 of 307). The unadjusted swine seroprevalence and seroincidence rates increased exponentially by 12.0% (95% confidence [CI] = 9.7-14.3%) and 32.8% (95% CI = 25.0-41.0%), respectively when distance to carriers decreased by half. Swine seroprevalence was 18.4% at > 500 meters from a carrier, 36.5% between 51 and 500 meters, and 68.9% within 50 meters (P < 0.001). Swine seroincidence also displayed a strong gradient near Tapeworm carriers (3.8%, 12.2%, and 44.0%; P < 0.001). Within 50 meters, swine seroprevalence appeared unaffected if the owners harbored Tapeworms, although pigs owned by a Tapeworm carrier had a four times higher seroincidence compared with other pigs (P = 0.005). In rural areas, swine cysticercosis occurs in high-risk hotspots around carriers where control interventions could be delivered.
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development of a serologic assay to detect taenia solium taeniasis
American Journal of Tropical Medicine and Hygiene, 1999Co-Authors: Patricia P Wilkins, Hector H Garcia, Armando E Gonzalez, Robert H Gilman, J C Allan, Manuela Verastegui, Mariela Acosta, Adam G Eason, Victor C W TsangAbstract:We developed a serologic assay to identify adult Taenia solium Tapeworm carriers using excretory/secretory (TSES) antigens collected from in vitro cultured T. solium Tapeworms. To identify taeniasis-specific antigens we used an immunoblot assay with serum samples from T. solium Tapeworm carriers and cysticercosis patients. Antigens were identified that reacted with antibodies present in serum samples from taeniasis cases and not with those from cysticercosis patients. Using serum samples collected from persons with confirmed T. solium Tapeworm infections, the test was determined to be 95% (69 of 73) sensitive. Serum samples (n = 193) from persons with other parasitic infections, including T. saginata Tapeworm infections, do not contain cross-reacting antibodies to TSES, indicating that the assay is 100% specific. These data suggest that the immunoblot assay using TSES antigens can be used to identify persons with current or recent T. solium Tapeworm infections and provides a new, important tool for epidemiologic purposes, including control and prevention strategies.
