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Sample records for anti-schistosoma mansoni human

  1. A new rapid diagnostic test for detection of anti-Schistosoma mansoni and anti-Schistosoma haematobium antibodies

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    Coulibaly Jean T

    2013-01-01

    Full Text Available Abstract Background Parasitological methods are widely used for the diagnosis of schistosomiasis. However, they are insensitive, particularly in areas of low endemicity, and labour-intensive. Immunoassays based on detection of anti-schistosome antibodies have the merit of high sensitivity and recently a rapid diagnostic test (RDT, incorporating Schistosoma mansoni cercarial transformation fluid (SmCTF for detection of anti-schistosome antibodies in blood has been developed. Here, we assessed the diagnostic performance of the SmCTF-RDT for S. mansoni and S. haematobium infections by comparing it with microscopy for egg detection. Methods A cross-sectional survey was carried out in Azaguié, south Côte d’Ivoire. 118 pre-school-aged children submitted two stool and two urine samples, which were subjected to the Kato-Katz and urine filtration methods for the detection of S. mansoni and S. haematobium eggs, respectively. Urine was also subjected to a commercially available cassette test for S. mansoni, which detects circulating cathodic antigen. A finger-prick blood sample was used for the SmCTF-RDT for detection of anti-S. mansoni and anti-S. haematobium antibodies. Results The prevalence of both anti-S. mansoni and anti-S. haematobium antibodies was more than three times higher than the prevalence of infection estimated by egg detection under a microscope. Using quadruplicate Kato-Katz as the reference standard for the diagnosis of S. mansoni infection, the sensitivity, negative predictive value (NPV, and positive predictive value (PPV of the SmCTF-RDT was 75.0%, 84.2% and 22.5%, respectively. When two urine filtrations were considered as the reference standard for the diagnosis of S. haematobium infection, the sensitivity, NPV and PPV of SmCTF-RDT was 66.7%, 94.9% and 5.1%, respectively. The specificity of SmCTF-RDT, when using egg-detection as the reference standard, was estimated to be 34.4%. This low specificity may be a reflection of the

  2. Evaluation of anti-Schistosoma mansoni igG antibodies in patients with chronic schistosomiasis mansoni before and after specific treatment Avaliação da presença de anticorpos IgG anti-Schistosoma mansoni no soro de pacientes com esquistossomose mansônica crônica, antes e após tratamento específico

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    Célia Maria V. VENDRAME

    2001-06-01

    Full Text Available The circumoval precipitin test (COPT, enzyme-linked immunosorbent assay (ELISA and the immunoblotting anti-adult worm antigen (AWA and soluble egg antigen (SEA tests were applied to 17 chronically schistosome-infected patients for the detection of anti-Schistosoma mansoni antibodies before and on four occasions after oxamniquine administration over a period of six months. Compared to a control group, schistosomiasis patients showed high levels of IgG antibodies in AWA and SEA-ELISA. A decrease in IgG levels was observed six months after treatment, although negative reactions were not obtained. Significant decreases in IgG1, IgG3 and, mainly, IgG4, but not anti-SEA IgG2 levels were observed six months after treatment, again without negativity. Analysis of anti-AWA IgG antibodies by immunoblotting before treatment showed a 31 kDa strand in 14 patients (82% which disappeared in three cases up to six months after treatment; furthermore, anti-SEA IgG antibodies showed the same band in nine patients (53% before treatment, which disappeared in only four cases up to six months after treatment.Em 17 pacientes com infecção crônica por Schistosoma mansoni utilizaram-se os testes de reação periovular, imunoenzimático (ELISA e imunoblotting, empregando-se antígenos obtidos a partir de vermes adultos (AWA ou de ovos de S. mansoni (SEA, para detecção de anticorpos anti-S. mansoni, antes e em quatro ocasiões após tratamento com oxamniquine. Quando cotejados a grupo controle os pacientes esquistossomóticos revelaram altos níveis séricos de anticorpos IgG nos testes ELISA (anti-AWA e anti-SEA, não se observando, porém, negativação até seis meses após tratamento específico. Encontrou-se, entretanto, decréscimo significativo, sem negativação, dos níveis de IgG1, IgG3 e, principalmente, IgG4, quando se utilizou antígeno solúvel obtido a partir de ovos de S. mansoni (SEA, seis meses após administração de oxamniquine. O mesmo não foi

  3. Metabonomic investigation of human Schistosoma mansoni infection

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    Balog, Crina I.A.; Meissner, Axel; Göraler, Sibel;

    2011-01-01

    involving a well-characterized cohort of 447 individuals from a rural area in Uganda near Lake Victoria with a high prevalence of Schistosoma mansoni, a species predominantly occurring in Africa including Madagascar and parts of South America. Cohort samples were collected from individuals at five time...... in their urinary profiles. The potential molecular markers of S. mansoni infection were found to be primarily linked to changes in gut microflora, energy metabolism and liver function. These findings are in agreement with data from earlier studies on S. mansoni infection in experimental animals and thus provide...

  4. Osteopontin Is Upregulated in Human and Murine Acute Schistosomiasis Mansoni

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    Pereira, Thiago Almeida; Syn, Wing-Kin; Amâncio, Frederico Figueiredo; Cunha, Pedro Henrique Diniz; Caporali, Julia Fonseca Morais; Trindade, Guilherme Vaz de Melo; Santos, Elisângela Trindade; Souza, Márcia Maria; Andrade, Zilton Araújo; Witek, Rafal P; Secor, William Evan; Pereira, Fausto Edmundo Lima; Lambertucci, José Roberto; Diehl, Anna Mae

    2016-01-01

    Background Symptomatic acute schistosomiasis mansoni is a systemic hypersensitivity reaction against the migrating schistosomula and mature eggs after a primary infection. The mechanisms involved in the pathogenesis of acute schistosomiasis are not fully elucidated. Osteopontin has been implicated in granulomatous reactions and in acute hepatic injury. Our aims were to evaluate if osteopontin plays a role in acute Schistosoma mansoni infection in both human and experimentally infected mice and if circulating OPN levels could be a novel biomarker of this infection. Methodology/Principal Findings Serum/plasma osteopontin levels were measured by ELISA in patients with acute (n = 28), hepatointestinal (n = 26), hepatosplenic (n = 39) schistosomiasis and in uninfected controls (n = 21). Liver osteopontin was assessed by immunohistochemistry in needle biopsies of 5 patients. Sera and hepatic osteopontin were quantified in the murine model of schistosomiasis mansoni during acute (7 and 8 weeks post infection, n = 10) and chronic (30 weeks post infection, n = 8) phase. Circulating osteopontin levels are increased in patients with acute schistosomiasis (p = 0.0001). The highest levels of OPN were observed during the peak of clinical symptoms (7–11 weeks post infection), returning to baseline level once the granulomas were modulated (>12 weeks post infection). The plasma levels in acute schistosomiasis were even higher than in hepatosplenic patients. The murine model mirrored the human disease. Macrophages were the major source of OPN in human and murine acute schistosomiasis, while the ductular reaction maintains OPN production in hepatosplenic disease. Soluble egg antigens from S. mansoni induced OPN expression in primary human kupffer cells. Conclusions/Significance S. mansoni egg antigens induce the production of OPN by macrophages in the necrotic-exudative granulomas characteristic of acute schistosomiasis mansoni. Circulating OPN levels are upregulated in human and

  5. Whole genome resequencing of the human parasite Schistosoma mansoni reveals population history and effects of selection

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    Crellen, Thomas; Allan, Fiona; David, Sophia; Durrant, Caroline; Huckvale, Thomas; Holroyd, Nancy; Emery, Aidan M.; Rollinson, David; Aanensen, David M.; Berriman, Matthew; Webster, Joanne P.; Cotton, James A.

    2016-01-01

    Schistosoma mansoni is a parasitic fluke that infects millions of people in the developing world. This study presents the first application of population genomics to S. mansoni based on high-coverage resequencing data from 10 global isolates and an isolate of the closely-related Schistosoma rodhaini, which infects rodents. Using population genetic tests, we document genes under directional and balancing selection in S. mansoni that may facilitate adaptation to the human host. Coalescence modeling reveals the speciation of S. mansoni and S. rodhaini as 107.5–147.6KYA, a period which overlaps with the earliest archaeological evidence for fishing in Africa. Our results indicate that S. mansoni originated in East Africa and experienced a decline in effective population size 20–90KYA, before dispersing across the continent during the Holocene. In addition, we find strong evidence that S. mansoni migrated to the New World with the 16–19th Century Atlantic Slave Trade. PMID:26879532

  6. Isoforms of Hsp70-binding human LDL in adult Schistosoma mansoni worms.

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    Pereira, Adriana S A; Cavalcanti, Marília G S; Zingali, Russolina B; Lima-Filho, José L; Chaves, Maria E C

    2015-03-01

    Schistosoma mansoni is one of the most common parasites infecting humans. They are well adapted to the host, and this parasite's longevity is a consequence of effective escape from the host immune system. In the blood circulation, lipoproteins not only help to conceal the worm from attack by host antibodies but also act as a source of lipids for S. mansoni. Previous SEM studies showed that the low-density lipoprotein (LDL) particles present on the surface of adult S. mansoni worms decreased in size when the incubation time increased. In this study, immunocytochemical and proteomic analyses were used to locate and identify S. mansoni binding proteins to human plasma LDL. Ultrathin sections of adult worms were cut transversely from the anterior, medial and posterior regions of the parasite. Immunocytochemical experiments revealed particles of gold in the tegument, muscle region and spine in male worms and around vitelline cells in females. Immunoblotting and 2D-electrophoresis using incubations with human serum, anti-LDL antibodies and anti-chicken IgG peroxidase conjugate were performed to identify LDL-binding proteins in S. mansoni. Analysis of the binding proteins using LC-MS identified two isoforms of the Hsp70 chaperone in S. mansoni. Hsp70 is involved in the interaction with apoB in the cytoplasm and its transport to the endoplasmic reticulum. However, further studies are needed to clarify the functional role of Hsp70 in S. mansoni, mainly related to the interaction with human LDL.

  7. Human schistosomiasis mansoni: studies on in vitro granuloma modulation

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    Juçara C. Parra

    1992-01-01

    Full Text Available Infection with Schistosoma mansoni induces humoral and T cell mediated responses and leads to delayed hipersensitivity that results in granulomatous inflamatory disease around the parasite eggs. Regulation of these responses resulting in a reduction in this anti-egg inflamatory disease is appsrently determined by idiotypic repertoires of the patient, associated with genetic background and multiple external factors. We have previously reported on idiotype/anti-idiotype-receptor transactions in clinical human schistosomiasis. These findings support a hypothesis that anti-SEA cross-reactive idiotypes develop in some patients during the course of a chronic infection and participate in regulation of anti-SEA cellular immune responses. We repport here on experiments wich extend those observations to the regulation of granulomatous hypersensitivity measured by an in vitro granuloma model. T cells from chronic intestinal schistosomiasis patients were stimulated in vitro with anti-SEA idiotypes and assayed in an autologous in vitro granuloma assay for modulation of granuloma formation. These anti-SEA idiotype reactive T cells were capable of regulating autologous in vitro granuloma formation. This regulatory activity, initiated with stimulatory anti-SEA idiotypic antibodies, was antigenically specific and was dependent on the present of intact (F(ab'2 immunoglobulin molecules. The ability to elicit this regulatory activity appears to be dose dependent and is more easily demonstrated in chronically infected intestinal patients or SEA sensitized individuals. These data support the hypothesis that anti-SEA cross reactive idiotypes are important in regulating granulomatous hypersensitivy in chronic intestinal schistosomiasis patients and these cross-reactive idiotypes appear to play a major role in cell-cell interactions which result in the regulation of anti-SEA cellular immune responses.

  8. Antibody response to Salmonella typhi lw human Schistosomiasis mansoni

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    Maria Imaculada Muniz-Junqueira

    1996-10-01

    Full Text Available Antibody response to Salmonella typhi O and H antigens was evaluated in 24 individuals with either hepatointestinal or hepatosplenic schistosomiasis mansoni before and after typhoid vaccination, and compared with that of non-infected controls. Before vaccination, Schistosoma-infected patients showed a higher frequency of positive antibody to O antigen and the same frequency to H antigen when compared with that of healthy individuals. However, those with hepatosplenic schistosomiasis showed higher titres of antibody to H antigen than those with hepatointestinal disease or healthy individuals. Infected subjects, particularly those with hepatointestinal disease, showed a decreased response after typhoid vaccine. Tins diminished ability to mount an immune response towards typhoid antigens dining schistosomiasis may interfere ivith the clearance of the bacteria from blood stream and, therefore, play a role in the prolonged survival of salmonella as obsewed in some patients with chronic salmonellosis associated with schistosomiasis.

  9. Antibody response to Salmonella typhi lw human Schistosomiasis mansoni

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    Maria Imaculada Muniz-Junqueira

    1996-10-01

    Full Text Available Antibody response to Salmonella typhi O and H antigens was evaluated in 24 individuals with either hepatointestinal or hepatosplenic schistosomiasis mansoni before and after typhoid vaccination, and compared with that of non-infected controls. Before vaccination, Schistosoma-infected patients showed a higher frequency of positive antibody to O antigen and the same frequency to H antigen when compared with that of healthy individuals. However, those with hepatosplenic schistosomiasis showed higher titres of antibody to H antigen than those with hepatointestinal disease or healthy individuals. Infected subjects, particularly those with hepatointestinal disease, showed a decreased response after typhoid vaccine. Tins diminished ability to mount an immune response towards typhoid antigens dining schistosomiasis may interfere ivith the clearance of the bacteria from blood stream and, therefore, play a role in the prolonged survival of salmonella as obsewed in some patients with chronic salmonellosis associated with schistosomiasis.A resposta de anticorpos para os antígenos O e H da Salmonella typhi foi avaliada em 24 indivíduos com esquistossomose hepatointestinal ou hepatoesplênica antes e apôs vacinação antitifoídica, e comparada com a resposta de indivíduos controles normais. Antes da vacinação, pacientes esquistossomóticos mostraram uma maior frequência de anticoipos positivos para o antígeno O e a mesma frequência de anticoipos positivos para o antígeno H quando comparada com aquela de indivíduos controles normais. Porém, aqueles com esquistossomose hepatoesplênica mostraram títulos maiores de anticoipos para o antígeno H do que aqueles com a forma hepatointestinal da doença ou os indivíduos controles normais. Pacientes esquistossomóticos, particularmente aqueles com a forma hepatointestinal, mostraram uma menor resposta após a vacinação antitifoídica. Esta menor capacidade para apresentar uma resposta imune para ant

  10. Schistosoma mansoni

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    Friis, Henrik; Byskov, Jens

    1987-01-01

    Recent surveys in Ngamiland, Botswana, indicate increasing prevalence of Schistosoma mansoni infections. With the introduction of a schistosomiasis control programme, 354 of 373 schoolchildren were examined quantitatively for eggs of S. mansoni, and 317 were examined clinically for hepato...

  11. Cytokine profile associated with chronic and acute human schistosomiasis mansoni

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    Clarice Neuenschwander Lins de Morais

    2008-09-01

    Full Text Available The production and regulation of interleukin (IL IL-13, IL-4 and interferon-gamma (IFN-³ was evaluated in 43 schistosomiasis patients with different clinical forms. Whole-blood cultures cytokine production in response to soluble egg antigen (SEA, soluble worm adult preparation (SWAP, mitogens, neutralizing antibodies or recombinant IL-13 were measured by ELISA. After SWAP stimulation, chronic patients, particularly hepatointestinals, produced higher levels of IL-4 in comparison with acute patients, suggesting the presence of a type 2 cytokine profile in these patients. Following SEA and SWAP stimulation, hepatosplenic (HS patients showed increased levels of IFN-³ when compared with acute patients, indicating that HS disease in humans is associated with a type 1 cytokine response. The mechanisms of immune regulation are apparently different between the clinical stages of the disease, some of which are antigen-specific.

  12. An In-Depth Analysis of a Piece of Shit: Distribution of Schistosoma mansoni and Hookworm Eggs in Human Stool

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    Stefanie J Krauth; Coulibaly, Jean T.; Stefanie Knopp; Mahamadou Traoré; Eliézer K. N'Goran; Jürg Utzinger

    2012-01-01

    BACKGROUND: An accurate diagnosis of helminth infection is important to improve patient management. However, there is considerable intra- and inter-specimen variation of helminth egg counts in human feces. Homogenization of stool samples has been suggested to improve diagnostic accuracy, but there are no detailed investigations. Rapid disintegration of hookworm eggs constitutes another problem in epidemiological surveys. We studied the spatial distribution of Schistosoma mansoni and hookworm ...

  13. An in-depth analysis of a piece of shit: distribution of Schistosoma mansoni and hookworm eggs in human stool.

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    Stefanie J Krauth

    Full Text Available BACKGROUND: An accurate diagnosis of helminth infection is important to improve patient management. However, there is considerable intra- and inter-specimen variation of helminth egg counts in human feces. Homogenization of stool samples has been suggested to improve diagnostic accuracy, but there are no detailed investigations. Rapid disintegration of hookworm eggs constitutes another problem in epidemiological surveys. We studied the spatial distribution of Schistosoma mansoni and hookworm eggs in stool samples, the effect of homogenization, and determined egg counts over time in stool samples stored under different conditions. METHODOLOGY: Whole-stool samples were collected from 222 individuals in a rural part of south Côte d'Ivoire. Samples were cut into four pieces and helminth egg locations from the front to the back and from the center to the surface were analyzed. Some samples were homogenized and fecal egg counts (FECs compared before and after homogenization. The effect of stool storing methods on FECs was investigated over time, comparing stool storage on ice, covering stool samples with a water-soaked tissue, or keeping stool samples in the shade. PRINCIPAL FINDINGS: We found no clear spatial pattern of S. mansoni and hookworm eggs in fecal samples. Homogenization decreased S. mansoni FECs (p = 0.026, while no effect was observed for hookworm and other soil-transmitted helminths. Hookworm FECs decreased over time. Storing stool samples on ice or covered with a moist tissue slowed down hookworm egg decay (p<0.005. CONCLUSIONS/SIGNIFICANCE: Our findings have important implications for helminth diagnosis at the individual patient level and for epidemiological surveys, anthelmintic drug efficacy studies and monitoring of control programs. Specifically, homogenization of fecal samples is recommended for an accurate detection of S. mansoni eggs, while keeping collected stool samples cool and moist delayed the disintegration of

  14. Prophylactic effect of artemether on human schistosomiasis mansoni among Egyptian children: A randomized controlled trial.

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    Elmorshedy, Hala; Tanner, Marcel; Bergquist, Robert N; Sharaf, Soraya; Barakat, Rashida

    2016-06-01

    A double-blind, randomized controlled trial was conducted in an endemic focus for Schistosoma mansoni in Kafr El-Sheikh Governorate, Northern Nile Delta, Egypt, to evaluate the prophylactic effect of artemether (ART) given in conjunction with praziquantel (PZQ). The study encompassed 913 primary school children randomly assigned to two treatment groups PZQ/ART and PZQ/ART-placebo. At baseline, both groups received 40 mg/kg body weight of PZQ twice four weeks apart, after which one group received 6 mg/kg body weight of ART every 3 weeks in 5 cycles during the transmission season and the other group received ART-placebo. At the end of the study, prevalence of infection among the PZQ/ART was approximately half that of the PZQ/ART-placebo group, i.e. 6.7% versus 11.6%, and incidence of new infections for the PZQ/ART was 2.7% versus 6.5% for the PZQ/ART-placebo. In conclusion, PZQ/ART combined therapy might be considered as an adjunct measure against human schistosomiasis, by specifically reducing transmission and therefore contribute to disease elimination. PMID:26921676

  15. A salting out and resin procedure for extracting Schistosoma mansoni DNA from human urine samples

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    Rodrigues Nilton B

    2010-04-01

    Full Text Available Abstract Background In this paper a simple and cheap salting out and resin (InstaGene matrix® resin - BioRad DNA extraction method from urine for PCR assays is introduced. The DNA of the fluke Schistosoma mansoni was chosen as the target since schistosomiasis lacks a suitable diagnostic tool which is sensitive enough to detect low worm burden. It is well known that the PCR technique provides high sensitivity and specificity in detecting parasite DNA. Therefore it is of paramount importance to take advantage of its excellent performance by providing a simple to handle and reliable DNA extraction procedure, which permits the diagnosis of the disease in easily obtainable urine samples. Findings The description of the extraction procedure is given. This extraction procedure was tested for reproducibility and efficiency in artificially contaminated human urine samples. The reproducibility reached 100%, showing positive results in 5 assay repetitions of 5 tested samples each containing 20 ng DNA/5 ml. The efficiency of the extraction procedure was also evaluated in a serial dilution of the original 20 ng DNA/5 ml sample. Detectable DNA was extracted when it was at a concentration of 1.28 pg DNA/mL, revealing the high efficiency of this procedure. Conclusions This methodology represents a promising tool for schistosomiasis diagnosis utilizing a bio-molecular technique in urine samples which is now ready to be tested under field conditions and may be applicable to the diagnosis of other parasitic diseases.

  16. Polymyxin B as inhibitor of LPS contamination of Schistosoma mansoni recombinant proteins in human cytokine analysis

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    Pacífico Lucila G

    2007-01-01

    Full Text Available Abstract Background Recombinant proteins expressed in Escherichia coli vectors are generally contaminated with endotoxin. In this study, we evaluated the ability of Polymyxin B to neutralize the effect of LPS present as contaminant on Schistosoma mansoni recombinant proteins produced in E. coli in inducing TNF-α and IL-10. Peripheral blood mononuclear cells from individuals chronically infected with S. mansoni were stimulated in vitro with recombinant Sm22.6, Sm14 and P24 antigens (10 μg/mL in the presence of Polymyxin B (10 μg/mL. Results The levels of cytokines were measured using ELISA. There was greater than 90 % reduction (p S. mansoni recombinant proteins in the presence of Polymyxin B, a reduction in the levels of TNF-α and IL-10 was also observed. However, the percentage of reduction was lower when compared to the cultures stimulated with LPS, probably because these proteins are able to induce the production of these cytokines by themselves. Conclusion This study showed that Polymyxin B was able to neutralize the effect of endotoxin, as contaminant in S. mansoni recombinant antigens produced in E. coli, in inducing TNF-α and IL-10 production.

  17. Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal.

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    Frederik Van den Broeck

    2015-08-01

    Full Text Available Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the '80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history.Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1 and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i many genetically different haplotypes at the non-recombining mitochondrial marker and (ii one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic.Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease.

  18. Use of a new glass microfibre histamine release method to study the modulation of the host response in human schistosomiasis mansoni. Individuals with different degrees of exposure to the disease show differing antibody biological function

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    Satti, M.Z.; Ebbesen, F.; Vennervald, B.;

    1996-01-01

    A new glass microfibre histamine release method was used to study the modulation of the host response in human schistosomiasis mansoni to improve our understanding of the role of basophils in the development of immunity in schistosomiasis mansoni. The histamine release from umbilical cord blood b...... basophils sensitized with sera from Sudanese individuals infected with Schistosoma mansoni was measured. Schistosomiasis sera (n=113) were able to passively sensitize basophils and induce a positive histamine release in response to whole worm homogenate (WWH)(chi(2)=40.5, P......A new glass microfibre histamine release method was used to study the modulation of the host response in human schistosomiasis mansoni to improve our understanding of the role of basophils in the development of immunity in schistosomiasis mansoni. The histamine release from umbilical cord blood...

  19. 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.; Diepen, A. van; 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 o

  20. Immunopathology of human schistosomiasis mansoni: II. NK activity and stimulation by specific antigen

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    L. K. Benarroch

    1988-12-01

    Full Text Available Sixteen S. mansoni infected and untreated patients (5 with recent infection and 11 with chronic disease were evaluated for their in vitro natural killer (NK activity against the NK sensitive target K562 cell line. NK levels in 9 out of 11 patients (82% with chronic disease were significantly lower (mean = 15 ± 6%,compared with patients recently infected (mean = 41 ± 9% p < 0.001 and with the control group (mean = 38 ± 13% p < 0.001. However, both patients and controls NK activity was stimulated by soluble adult worm antigens (SAWA, indicating that NK function even in the chronic stage of the infection is able to respond to the parasite antigens. These results suggest the possibility of NK cell participation as effector mechanism against S. mansoni.

  1. Bronchial Sparganosis mansoni accompanied by abnormal hyperplasia diagnosed by bronchoscopy

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    BAI Jing; HE Zhi-yi; LIU Guang-nan; ZHANG Jian-quan; DENG Jing-min; LI Mei-hua; ZHONG Xiao-ning

    2012-01-01

    Pulmonary sparganosis mansoni is rare in humans and bronchial sparganosis mansoni has not been reported.We reported a patient with a soft-tissue mass in the right hilum area on a chest computed tomography (CT) scan that was suspected of being lung cancer.Bronchoscopy identified sparganum larvae.Bronchial sparganosis mansoni accompanied by abnormal hyperplasia was diagnosed by histopathology.We introduced our experience and reviewed the clinical characteristics of three pulmonary sparganosis mansoni cases and three pleural cavity sparganosis mansoni cases that have been reoorted.

  2. 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.

  3. Optimal sample storage and extraction procotols for reliable multilocus genotyping of the human parasite Schistosoma mansoni.

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    Van den Broeck, F; Geldof, S; Polman, K; Volckaert, F A M; Huyse, T

    2011-08-01

    Genotyping individual larval stages and eggs of natural parasite populations is complicated by the difficulty of obtaining reliable genotypes from low quantity DNA template. A suitable storage and extraction protocol, together with a thorough quantification of genotyping errors are therefore crucial for molecular epidemiological studies. Here we test the robustness, handling time, ease of use, cost effectiveness and success rate of various fixation (Whatman FTA(®) Classic and Elute Cards, 70% EtOH and RNAlater(®)) and subsequent DNA extraction methods (commercial kits and proteinase K protocol). None of these methods require a cooling chain and are therefore suitable for field collection. Based on a multiplex microsatellite PCR with nine loci the success and reliability of each technique is evaluated by the proportion of samples with at least eight scored loci and the proportion of genotyping errors. If only the former is taken into account, FTA(®) Elute is recommended (83% success; 44% genotyping error; 0.2 €/sample; 1h 20 m handling time). However, when also considering the genotyping errors, handling time and ease of use, we opt for 70% EtOH with the 96-well plate technology followed by a simple proteinase K extraction (73% success; 0% genotyping error; 0.2 €/sample; 15m handling time). For eggs we suggest (1) to pool all eggs per person in 1.5 ml tubes filled with 70% EtOH for transport and (2) to identify each egg to species level prior to genotyping. To this end we extended the Rapid diagnostic PCR developed by Webster et al. (2010) with a S. mansoni-specific primer to discriminate between S. mansoni, S. haematobium and S. bovis in a single PCR reaction. The success rate of genotyping eggs was 75% (0% genotyping error). This is the first study to incorporate genotyping errors through re-amplification for the evaluation of schistosome sampling protocols and the identification of error-prone loci.

  4. Small gene family encoding an eggshell (chorion) protein of the human parasite Schistosoma mansoni

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    Bobek, L.A.; Rekosh, D.M.; Lo Verde, P.T.

    1988-08-01

    The authors isolated six independent genomic clones encoding schistosome chorion or eggshell proteins from a Schistosoma mansoni genomic library. A linkage map of five of the clones spanning 35 kilobase pairs (kbp) of the S. mansoni genome was constructed. The region contained two eggshell protein genes closely linked, separated by 7.5 kbp of intergenic DNA. The two genes of the cluster were arranged in the same orientation, that is, they were transcribed from the same strand. The sixth clone probably represents a third copy of the eggshell gene that is not contained within the 35-kbp region. The 5- end of the mRNA transcribed from these genes was defined by primer extension directly off the RNA. The ATCAT cap site sequence was homologous to a silkmoth chorion PuTCATT cap site sequence, where Pu indicates any purine. DNA sequence analysis showed that there were no introns in these genes. The DNA sequences of the three genes were very homologous to each other and to a cDNA clone, pSMf61-46, differing only in three or four nucleotices. A multiple TATA box was located at positions -23 to -31, and a CAAAT sequence was located at -52 upstream of the eggshell transcription unit. Comparison of sequences in regions further upstream with silkmoth and Drosophila sequences revealed very short elements that were shared. One such element, TCACGT, recently shown to be an essential cis-regulatory element for silkmoth chorion gene promoter function, was found at a similar position in all three organisms.

  5. Human Schistosomiasis mansoni associated with hepatocellular carcinoma in Egypt: current perspective.

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    El-Tonsy, Manar Mahmoud; Hussein, Hesham Mohammed; Helal, Thanaa El-Sayed; Tawfik, Rania Ayman; Koriem, Khalid Mohamed; Hussein, Hend Mohamed

    2016-09-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. It was reported to account for about 4.7 % of chronic liver disease in Egyptian patients. The present study aimed at studying the different factors that may be implicated in the relationship of schistosomiasis mansoni with HCC in Egypt. A total of 75 Egyptian patients with primary liver tumours (HCC) were enrolled in this study. They were subjected to full history taking and indirect hemagglutination assay (IHA) for the diagnosis of schistosomiasis. According to the results, the patients were categorized into two groups: Group I: 29 patients with negative IHA for schistosomiasis and hepatitis C virus (HCV) positive with no history or laboratory evidence of previous or current Schistosoma mansoni infection. Group II: 46 patients with positive IHA for schistosomiasis and HCV positive. The significant higher proportion of HCC patients in the present study had concomitant HCV and schistosomiasis (61.3 %) compared to HCC patients with HCV alone (38.7 %) suggesting that the co-infection had increased the incidence of HCC among these patients. Analysis of the age distribution among HCC patients revealed that patients in Group II were younger in age at time of diagnosis of HCC with mean age 57.1 years, as compared to patients in Group I with mean age 64.3 years with a highly significant statistical difference between the 2 groups. HCC in Group II was more common in rural residents while it was more common in urban areas in Group I with a significant statistical difference between the 2 groups. Analysis of the sex distribution among the studied groups showed that HCC was more common in males than females in both groups. As regards the aggression of HCC, it was more commonly multifocal and larger in size in patients with concomitant infection than in patients with HCV alone. PMID:27605822

  6. 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

  7. Human IgG1 Responses to Surface Localised Schistosoma mansoni Ly6 Family Members Drop following Praziquantel Treatment.

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    Iain W Chalmers

    Full Text Available The heptalaminate-covered, syncytial tegument is an important anatomical adaptation that enables schistosome parasites to maintain long-term, intravascular residence in definitive hosts. Investigation of the proteins present in this surface layer and the immune responses elicited by them during infection is crucial to our understanding of host/parasite interactions. Recent studies have revealed a number of novel tegumental surface proteins including three (SmCD59a, SmCD59b and Sm29 containing uPAR/Ly6 domains (renamed SmLy6A SmLy6B and SmLy6D in this study. While vaccination with SmLy6A (SmCD59a and SmLy6D (Sm29 induces protective immunity in experimental models, human immunoglobulin responses to representative SmLy6 family members have yet to be thoroughly explored.Using a PSI-BLAST-based search, we present a comprehensive reanalysis of the Schistosoma mansoni Ly6 family (SmLy6A-K. Our examination extends the number of members to eleven (including three novel proteins and provides strong evidence that the previously identified vaccine candidate Sm29 (renamed SmLy6D is a unique double uPAR/Ly6 domain-containing representative. Presence of canonical cysteine residues, signal peptides and GPI-anchor sites strongly suggest that all SmLy6 proteins are cell surface-bound. To provide evidence that SmLy6 members are immunogenic in human populations, we report IgG1 (as well as IgG4 and IgE responses against two surface-bound representatives (SmLy6A and SmLy6B within a cohort of S. mansoni-infected Ugandan males before and after praziquantel treatment. While pre-treatment IgG1 prevalence for SmLy6A and SmLy6B differs amongst the studied population (7.4% and 25.3% of the cohort, respectively, these values are both higher than IgG1 prevalence (2.7% for a sub-surface tegumental antigen, SmTAL1. Further, post-treatment IgG1 levels against surface-associated SmLy6A and SmLy6B significantly drop (p = 0.020 and p < 0.001, respectively when compared to rising Ig

  8. Monoclonal antibody-based dipstick assay: a reliable field applicable technique for diagnosis of Schistosoma mansoni infection using human serum and urine samples.

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    Demerdash, Zeinab; Mohamed, Salwa; Hendawy, Mohamed; Rabia, Ibrahim; Attia, Mohy; Shaker, Zeinab; Diab, Tarek M

    2013-02-01

    A field applicable diagnostic technique, the dipstick assay, was evaluated for its sensitivity and specificity in diagnosing human Schistosoma mansoni infection. A monoclonal antibody (mAb) against S. mansoni adult worm tegumental antigen (AWTA) was employed in dipstick and sandwich ELISA for detection of circulating schistosome antigen (CSA) in both serum and urine samples. Based on clinical and parasitological examinations, 60 S. mansoni-infected patients, 30 patients infected with parasites other than schistosomiasis, and 30 uninfected healthy individuals were selected. The sensitivity and specificity of dipstick assay in urine samples were 86.7% and 90.0%, respectively, compared to 90.0% sensitivity and 91.7% specificity of sandwich ELISA. In serum samples, the sensitivity and specificity were 88.3% and 91.7% for dipstick assay vs. 91.7% and 95.0% for sandwich ELISA, respectively. The diagnostic efficacy of dipstick assay in urine and serum samples was 88.3% and 90.0%, while it was 90.8% and 93.3% for sandwich ELISA, respectively. The diagnostic indices of dipstick assay and ELISA either in serum or in urine were statistically comparable (P>0.05). In conclusion, the dipstick assay offers an alternative simple, rapid, non-invasive technique in detecting CSA or complement to stool examinations especially in field studies. PMID:23467705

  9. The Schistosoma mansoni tegumental-allergen-like (TAL protein family: influence of developmental expression on human IgE responses.

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    Colin M Fitzsimmons

    Full Text Available BACKGROUND: A human IgE response to Sm22.6 (a dominant IgE target in Schistosoma mansoni is associated with the development of partial immunity. Located inside the tegument, the molecule belongs to a family of proteins from parasitic platyhelminths, the Tegument-Allergen-Like proteins (TALs. In addition to containing dynein-light-chain domains, these TALs also contain EF-hand domains similar to those found in numerous EF-hand allergens. METHODOLOGY/PRINCIPAL FINDINGS: S. mansoni genome searches revealed 13 members (SmTAL1-13 within the species. Recent microarray data demonstrated they have a wide range of life-cycle transcriptional profiles. We expressed SmTAL1 (Sm22.6, SmTAL2, 3, 4, 5 and 13 as recombinant proteins and measured IgE and IgG4 in 200 infected males (7-60 years from a schistosomiasis endemic region in Uganda. For SmTAL1 and 3 (transcribed in schistosomula through adult-worms and adult-worms, respectively and SmTAL5 (transcribed in cercariae through adult-worms, detectable IgE responses were rare in 7-9 year olds, but increased with age. At all ages, IgE to SmTAL2 (expressed constitutively, was rare while anti-SmTAL2 IgG4 was common. Levels of IgE and IgG4 to SmTAL4 and 13 (transcribed predominantly in the cercariae/skin stage were all low. CONCLUSIONS: We have not measured SmTAL protein abundance or exposure in live parasites, but the antibody data suggests to us that, in endemic areas, there is priming and boosting of IgE to adult-worm SmTALs by occasional death of long-lived worms, desensitization to egg SmTALs through continuous exposure to dying eggs and low immunogenicity of larval SmTALs due to immunosuppression in the skin by the parasite. Of these, it is the gradual increase in IgE to the worm antigens that parallels age-dependent immunity seen in endemic areas.

  10. Cercarial Chaetotaxy and Sex Differentiation of Schistosoma mansoni Deriving from Humans and Nectomys squamipes (Muridae: Sigmondontinae in Brazil

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    Nilcéa Freire

    2002-01-01

    Full Text Available A comparative study was made between sympatric isolates of Schistosoma mansoni: one from a wild rodent (R Nectomys squamipes and another one from humans (H isolated from a low endemic schistosomiasis transmission area in Brazil. Our purpose was to detect differences between them concerning chaetotaxy (number and pattern of distribution of the argentophilic papillae of the cercariae by means of silver impregnation. No significant difference (x > 0.05 between isolates was noted. Nevertheless, a significant difference (x < 0.05 was observed in the cercarial index (ratio of the distance between the first and the second preacetabular papillae and the distance between the first and the second dorsal preacetabular papillae of male and female cercariae in both isolates. Males presented a greater cercarial index than females. By means of multivariate analysis, male cercariae were distinguished from female cercariae through the following characteristics: average number of dorsal papillae on the right quadrant, average number of ventral middle papillae on the right quadrant (H isolate and average number of dorsal middle papillae on the left quadrant (R isolate. The results suggest that R and H isolates belong to the same population that could complete its life cycle in rodent-snail-rodent fashion.

  11. Characteristics of the human host have little influence on which local Schistosoma mansoni populations are acquired.

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    Lúcio M Barbosa

    Full Text Available BACKGROUND: Brazil remains the country in the Americas with the highest prevalence of schistosomiasis. A combination of control efforts and development, however, has sharply reduced its intensity and distribution. The acquisition of specific schistosome populations may be dependent on host characteristics such as sex, age, geography, work, habits and culture. How these and other host characteristics align with parasite subpopulations may guide approaches to improve control. METHODOLOGY: A cohort of more than 90% of the residents in two rural communities in Brazil participated in an epidemiologic survey of demographic, socio-economic and behavioral characteristics. The variables sex, age, intensity of infection, socio-economic index, % lifetime spent on site, previous infection, and trips outside the district were used to group parasites infecting individuals. Schistosoma mansoni infection status was determined by examination of stools submitted on 3 different days. The aggregate of eggs collected from the whole stool was used to determine degree of population differentiation from allele frequencies for 15 microsatellites. CONCLUSIONS/SIGNIFICANCE: Infection prevalence was 41% for these communities, and the epidemiologic characteristics were similar to many of the endemic areas of Brazil and the world. Parasite population structuring was observed between the two communities (Jost's D 0.046, CI95% 0.042-0.051, although separated by only 8 km and connected by a highway. No structuring was observed when infected individuals were stratified by host's biologic, demographic or epidemiologic characteristics. Those most heavily infected best reflected the communities' overall parasite diversity. The lack of differentiation within villages suggests that individuals are likely to get infected at the same sites or that the same parasite multilocus genotypes can be found at most sites. The geographic structuring between villages and the lack of structuring

  12. Diagnostic accuracy and applicability of a PCR system for the detection of Schistosoma mansoni DNA in human urine samples from an endemic area.

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    Martin Johannes Enk

    Full Text Available Schistosomiasis caused by Schistosoma mansoni, one of the most neglected human parasitoses in Latin America and Africa, is routinely confirmed by microscopic visualization of eggs in stool. The main limitation of this diagnostic approach is its lack of sensitivity in detecting individual low worm burdens and consequently data on infection rates in low transmission settings are little reliable. According to the scientific literature, PCR assays are characterized by high sensitivity and specificity in detecting parasite DNA in biological samples. A simple and cost effective extraction method for DNA of Schistosoma mansoni from urine samples in combination with a conventional PCR assay was developed and applied in an endemic area. This urine based PCR system was tested for diagnostic accuracy among a population of a small village in an endemic area, comparing it to a reference test composed of three different parasitological techniques. The diagnostic parameters revealed a sensitivity of 100%, a specificity of 91.20%, positive and negative predictive values of 86.25% and 100%, respectively, and a test accuracy of 94.33%. Further statistical analysis showed a k index of 0.8806, indicating an excellent agreement between the reference test and the PCR system. Data obtained from the mouse model indicate the infection can be detected one week after cercariae penetration, opening a new perspective for early detection and patient management during this stage of the disease. The data indicate that this innovative PCR system provides a simple to handle and robust diagnostic tool for the detection of S. mansoni DNA from urine samples and a promising approach to overcome the diagnostic obstacles in low transmission settings. Furthermore the principals of this molecular technique, based on the examination of human urine samples may be useful for the diagnosis of other neglected tropical diseases that can be detected by trans-renal DNA.

  13. Genome-wide identification of novel microRNAs and their target genes in the human parasite Schistosoma mansoni.

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    de Souza Gomes, Matheus; Muniyappa, Mohan Kumar; Carvalho, Sávio Gonçalves; Guerra-Sá, Renata; Spillane, Charles

    2011-08-01

    Mature microRNAs (miRNAs) are small, non-coding regulatory RNAs which can elicit post-transcriptional repression of mRNA levels of target genes. Here, we report the identification of 67 mature and 42 precursor miRNAs in the Schistosoma mansoni parasite. The evolutionarily conserved S. mansoni miRNAs consisted of 26 precursor miRNAs and 35 mature miRNAs, while we identified 16 precursor miRNAs and 32 mature miRNAs that displayed no conservation. These S. mansoni miRNAs are located on seven autosomal chromosomes and a sex (W) chromosome. miRNA expansion through gene duplication was suggested for at least two miRNA families miR-71 and mir-2. miRNA target finding analysis identified 389 predicted mRNA targets for the identified miRNAs and suggests that the sma-mir-71 may be involved in female sexual maturation. Given the important roles of miRNAs in animals, the identification and characterization of miRNAs in S. mansoni will facilitate novel approaches towards prevention and treatment of Schistosomiasis.

  14. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil

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    Delmany Moitinho Barboza

    2012-09-01

    Full Text Available The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  15. Diagnostic significance of Schistosoma mansoni proteins Sm31 and Sm32 in human schistosomiasis in an endemic area in Egypt.

    Science.gov (United States)

    El-Sayed, L H; Ghoneim, H; Demian, S R; El-Sayed, M H; Tawfik, N M; Sakr, I; Abou-Basha, L M; Renganathan, E; Klinkert, M Q; Abou-Rawash, N

    1998-09-01

    We performed a series of ELISAs to evaluate the diagnostic significance of two Schistosoma mansoni proteins, Sm31 (cysteine proteinase, cathepsin B) and Sm32 (asparaginyl endopeptidase). Our study populations were chosen from two villages in an endemic area close to Alexandria. Using fusion proteins MS2-Sm31 and MS2-Sm32 as antigens, 70% and 78.9%, respectively, of patient sera from 134 parasitologically confirmed cases reacted positively. The percentage of seropositivity increased to 84.5% when parasite-derived proteins Sm31 and Sm32 were used. The serum levels of antibodies to these two proteins in recombinant or native forms do not correlate with intensity of infection and hence are detected even when egg counts are low, which makes proteins Sm31 and Sm32 useful antigens in the identification of S. mansoni infected cases, particularly in endemic areas in Egypt. PMID:9754667

  16. Ectopic Schistosoma mansoni Eggs Inside a Lipoma.

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    Sabino, Kelly Renata; Nunes, Maurício Buzelin; Petroianu, Andy

    2016-01-01

    Ectopic schistosomiasis is uncommon and tends to occur when the parasite's eggs or adult forms are located far from their normal site. This report presents the first described case of ectopic Schistosoma mansoni eggs inside a subcutaneous lipoma far from the tissues of this worm's life cycle and with no connection to either portal veins or any other vascular system. These eggs were found inside giant cells surrounded by inflammatory cells. In conclusion, in humans, ectopic S. mansoni eggs can be found far from the tissues of the described life cycle of this worm, with no connection to portal veins or other blood vessels used for their migration. PMID:26598562

  17. Comparative evaluation of Schistosoma mansoni, Schistosoma intercalatum, and Schistosoma haematobium alkaline phosphatase antigenicity by the alkaline phosphatase immunoassay (APIA).

    Science.gov (United States)

    Cesari, I M; Ballén, D E; Mendoza, L; Ferrer, A; Pointier, J-P; Kombila, M; Richard-Lenoble, D; Théron, A

    2014-04-01

    To know if alkaline phosphatase (AP) from schistosomes other than Schistosoma mansoni can be used as diagnostic marker for schistosomiasis in alkaline phosphatase immunocapture assay (APIA), we comparatively tested n-butanol extracts of adult worm membranes from a Venezuelan (JL) strain of S. mansoni (Ven/AWBE/Sm); a Cameroonian (EDEN) strain of Schistosoma intercalatum (Cam/AWBE/Si) and a Yemeni strain of Schistosoma haematobium (Yem/AWBE/Sh). APIA was evaluated with sera of patients from Venezuela, Senegal, and Gabon infected with S. mansoni, from Gabon infected with S. intercalatum or S. haematobium, from Chine infected with Schistosoma japonicum and from Cambodian patients infected with Schistosoma mekongi. Results indicate that 92.5% (37/40) of Venezuela sera, 75% (15/20) of Senegal sera, 39.5% (17/43) of S. haematobium sera, and 19.2% (5/26) S. intercalatum sera were APIA-positive with the Ven/AWBE/Sm preparation. APIA with the Cam/AWBE/Si preparation showed that 53.8% of S. intercalatum-positive sera had anti-AP antibodies, and 51.2% S. haematobium-positive sera cross-immunocapturing the S. intercalatum AP. APIA performed with Yem/AWBE/Sh showed that 55.8% S. haematobium sera were positive. Only two out of nine S. japonicum sera were APIA-positive with the Ven/AWBE/Sm and Cam/AWBE/Si, and no reaction was observed with Cambodian S. mekongi-positive sera. AP activity was shown to be present in all the schistosome species/strains studied. The use of APIA as a tool to explore the APs antigenicity and the presence of Schistosoma sp. infections through the detection of anti-Schistosoma sp. AP antibodies in a host, allowed us to demonstrate the antigenicity of APs of S. mansoni, S. intercalatum, and S. haematobium.

  18. New insights into the reaction of Schistosoma mansoni cercaria to the human complement system.

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    Da'dara, Akram A; Krautz-Peterson, Greice

    2014-10-01

    Schistosomes are parasitic worms that have a complex life cycle. The larval stage cercaria, infectious to mammals, is described as highly susceptible to the complement system, largely due to the glycocalyx that covers the cercarial membrane. In an attempt to have a more complete understanding of cercaria reaction to the complement system, three different approaches were used. Live cercariae exposed to normal human serum (NHS) as source of complement factors were assessed for (i) membrane attack complex (MAC) deposition on the parasite surface, (ii) cercaria survival rate by Hoechst staining of parasite DNA, and (iii) transformation into schistosomula by detection of the glucose transporter protein 4 (SGTP4), a marker for new tegument formation. We found that 82-95% of cercariae directly exposed to NHS for 18 h were viable and retained their ability to shed the glycocalyx, suggesting minimal tegument damage. In contrast, inhibition of glycocalyx shedding using eserine caused significant MAC binding and parasite death. Culturing complement-exposed cercariae to measure long-term survival showed that more parasites died over time, reaching a survival rate of 18-31% by day 6 in culture. The reason for this slow death is unknown, but the surviving parasites were able to form a new tegument as shown by detection of SGTP4 on the parasite surface. Furthermore, we found that complement activation significantly damaged the acetabular gland ducts and lysed secretory vesicles released by transforming cercariae. These findings should contribute for future in vivo studies of the effects of the complement system in skin migrating cercariae.

  19. Schistosoma mansoni Soluble Egg Antigens Induce Expression of the Negative Regulators SOCS1 and SHP1 in Human Dendritic Cells via Interaction with the Mannose Receptor.

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    Elsenoor J Klaver

    Full Text Available Schistosomiasis is a common debilitating human parasitic disease in (subtropical areas, however, schistosome infections can also protect against a variety of inflammatory diseases. This has raised broad interest in the mechanisms by which Schistosoma modulate the immune system into an anti-inflammatory and regulatory state. Human dendritic cells (DCs show many phenotypic changes upon contact with Schistosoma mansoni soluble egg antigens (SEA. We here show that oxidation of SEA glycans, but not heat-denaturation, abrogates the capacity of SEA to suppress both LPS-induced cytokine secretion and DC proliferation, indicating an important role of SEA glycans in these processes. Remarkably, interaction of SEA glycans with DCs results in a strongly increased expression of Suppressor Of Cytokine Signalling1 (SOCS1 and SH2-containing protein tyrosine Phosphatase-1 (SHP1, important negative regulators of TLR4 signalling. In addition, SEA induces the secretion of transforming growth factor β (TGF-β, and the surface expression of the costimulatory molecules Programmed Death Ligand-1 (PD-L1 and OX40 ligand (OX40L, which are known phenotypic markers for the capacity of DCs to polarize naïve T cells into Th2/Treg cell subsets. Inhibition of mannose receptor (MR-mediated internalization of SEA into DCs by blocking with allyl α-D-mannoside or anti-MR antibodies, significantly reduced SOCS1 and SHP1 expression. In conclusion, we demonstrate that SEA glycans are essential for induction of enhanced SOCS1 and SHP1 levels in DCs via the MR. Our data provide novel mechanistic evidence for the potential of S. mansoni SEA glycans to modulate human DCs, which may contribute to the capacity of SEA to down-regulate inflammatory responses.

  20. Schistosoma mansoni Soluble Egg Antigens Induce Expression of the Negative Regulators SOCS1 and SHP1 in Human Dendritic Cells via Interaction with the Mannose Receptor.

    Science.gov (United States)

    Klaver, Elsenoor J; Kuijk, Loes M; Lindhorst, Thisbe K; Cummings, Richard D; van Die, Irma

    2015-01-01

    Schistosomiasis is a common debilitating human parasitic disease in (sub)tropical areas, however, schistosome infections can also protect against a variety of inflammatory diseases. This has raised broad interest in the mechanisms by which Schistosoma modulate the immune system into an anti-inflammatory and regulatory state. Human dendritic cells (DCs) show many phenotypic changes upon contact with Schistosoma mansoni soluble egg antigens (SEA). We here show that oxidation of SEA glycans, but not heat-denaturation, abrogates the capacity of SEA to suppress both LPS-induced cytokine secretion and DC proliferation, indicating an important role of SEA glycans in these processes. Remarkably, interaction of SEA glycans with DCs results in a strongly increased expression of Suppressor Of Cytokine Signalling1 (SOCS1) and SH2-containing protein tyrosine Phosphatase-1 (SHP1), important negative regulators of TLR4 signalling. In addition, SEA induces the secretion of transforming growth factor β (TGF-β), and the surface expression of the costimulatory molecules Programmed Death Ligand-1 (PD-L1) and OX40 ligand (OX40L), which are known phenotypic markers for the capacity of DCs to polarize naïve T cells into Th2/Treg cell subsets. Inhibition of mannose receptor (MR)-mediated internalization of SEA into DCs by blocking with allyl α-D-mannoside or anti-MR antibodies, significantly reduced SOCS1 and SHP1 expression. In conclusion, we demonstrate that SEA glycans are essential for induction of enhanced SOCS1 and SHP1 levels in DCs via the MR. Our data provide novel mechanistic evidence for the potential of S. mansoni SEA glycans to modulate human DCs, which may contribute to the capacity of SEA to down-regulate inflammatory responses. PMID:25897665

  1. Trace elements in the human scalp hair and finger nails as affected by infection with Schistosoma mansoni

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    El-Khatib, A.M. (Alexandria Univ. (Egypt). Dept. of Physics); Bahnassy, A.A. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Faculty of Medicine); Denton, M. (California Univ., Berkeley, CA (United States). Dept. of Nuclear Engineering)

    1995-01-01

    The concentration of 13 elements has been determined in finger nail and scalp hair of 4 groups representing normal and infected Schistosoma mansoni subjects. Samples were irradiated by thermal neutrons from a Triga Mark III Reactor, for 10 min. Measurements were made using a HPGe detector coupled with ADC and PDP 11/34 data processing equipment. The results showed significant increases of Al, Cl, I and Br in both finger nails and scalp hair of bilharzial patients above those of normal subjects while Mg, Ca, V, Mn, Cu, Sr, K, S and Na showed significant decreases. Most of the elements showed a higher concentration in finger nails than in hair. (author).

  2. Further evaluation of an updated PCR assay for the detection of Schistosoma mansoni DNA in human stool samples

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    Luciana I Gomes

    2009-12-01

    Full Text Available A previously reported sensitive PCR assay for the detection of Schistosoma mansoni DNA was updated and evaluated. Changes in the DNA extraction method, including the use of a worldwide available commercial kit and the inclusion of additional quality control measures, increased the robustness of the test, as confirmed by the analysis of 67 faecal samples from an endemic area in Brazil. The PCR assay is at hand as a proven, reliable diagnostic test for the control of schistosomiasis in specific settings.

  3. Analysis of complex patterns of human exposure and immunity to Schistosomiasis mansoni: the influence of age, sex, ethnicity and IgE.

    Directory of Open Access Journals (Sweden)

    Angela Pinot de Moira

    Full Text Available BACKGROUND: Numerous factors may influence Schistosoma infection intensity and prevalence within endemic communities, including exposure-related factors such as local environment and behaviour, and factors relating to susceptibility to infection such as immunology and genetics. While animal studies performed in the laboratory can be tightly controlled, human populations are highly heterogeneous, varying according to demographic characteristics, genetic background and exposure to infection. The heterogeneous nature of human water contact behaviour in particular makes it difficult to distinguish between a lack of cercarial exposure and reduced susceptibility to infection as the cause for low levels of infection in the field. METHODS AND PRINCIPAL FINDINGS: In this study we investigate risk factors for Schistosoma mansoni infection in a rural Ugandan fishing community receiving treatment as part of a multi-disciplinary longitudinal reinfection study. More specifically, we examine the influence that age, sex and ethnic background have on susceptibility to reinfection after anti-helminth drug treatment, but use individual estimates of cercarial exposure and multivariable methods in an attempt to remove noise created by environmental and behavioural heterogeneities. We then investigate whether schistosome-specific IgE immune responses could account for any remaining variations in susceptibility to reinfection. Our findings suggest that observed ethnic- and sex-related variations in S. mansoni reinfection were due to variations in cercarial exposure, as opposed to biological differences in susceptibility to infection. Age-related differences in reinfection were not explained by exposure, however, and appeared linked to the balance of IgE and IgG(4 to the tegumental antigen SmTAL1 (formerly Sm22.6, which itself was significantly related to resistance to reinfection. CONCLUSIONS: This study highlights the benefit of taking a multidisciplinary approach in

  4. Acute human schistosomiasis mansoni

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    Ana Rabello

    1995-04-01

    Full Text Available The acute schistosomiasis is the toxemic disease that follow the Schistosoma cercariae active penetration trough screen in the immunologicaly naive vertebrate host. The clinical picture starts two to eight weeks after the first contact with the contaminated water. Susceptible patients present a syndrome comprising fever, diarrhea, toxemia and hepatosplenomegaly. Diagnosis is based on epidemiological and clinical features, presence of Schistosoma eggs in the feces, enlargement of abdominal lymph nodes by ultrasonography and by detection of high antibodies levels against the antigen keyhole limpet haemocyanin. Different rates of cure have been observed with specific medication and for the most severe clinical presentations the use of steroids reduces the systemic and allergic manifestations.

  5. 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

    OpenAIRE

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

    2013-01-01

    Background 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...

  6. Schistosoma mansoni PIII antigen modulates in vitro granuloma formation by regulating CD28, CTLA-4, and CD86 expression in humans.

    Science.gov (United States)

    Zouain, C S; Falcão, P L; Goes, T S; Leite, M F; Goes, A M

    2004-02-15

    We investigated the in vitro responses of peripheral blood mononuclear cells (PBMC) from intestinal chronic schistosomiasis patients to PIII, a multivalent antigen prepared from Schistosoma mansoni adult worm. PIII decreased cellular proliferation and granulomatous reaction. Moreover, induced the reduction of IFN-gamma levels and increased IL-10 production. To better understand the mechanism through which the observed suppression occurs, the present study focused on the phenotypic pattern displayed by PBMC treated with PIII in an in vitro granuloma assay. Expression of the surface markers CD28, CTLA-4 and CD86 by lymphocytes and monocytes were analyzed by flow cytometry. Our results demonstrated a significant decrease of CD28+CD4+ and CD28+CD8+ T-cell percentage stimulated by PIII compared to its non-infected counterparts. This suppressive effect was related to a significant increase in the percentage of T-cells expressing CTLA-4. PIII also promoted a significant increase in the percentage of cells expressing CD86. Indeed, our results demonstrated that PIII was capable of modulating in vitro granuloma reaction, and this event was related to the balance of IL-10, IFN-gamma and CD28, CTLA-4, CD86 bringing new insight to the immunoregulation of granulomatous hypersensitivity in human schistosomiasis. PMID:15019278

  7. Avaliação terapêutica do praziquantel (Embay 8440) na infecção humana pelo S. mansoni Therapeutical investigation of praziquantel in human infection due to Schistosoma mansoni

    OpenAIRE

    Silvino Alves de Carvalho; Vicente Amato Neto; José Murilo Robilotta Zeitune; Moisés Goldbaum; Euclides Ayres de Castilho; Rose Mary Grossman

    1984-01-01

    Foram tratados com praziquantel, dose oral única de 40 ou 50 mg/kg, 200 indivíduos portadores de esquistossomose mansoni, matriculados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As idades dos pacientes variavam de seis a 63 anos, sendo que 33 (16,5%) eram menores de 15 anos. Os principais efeitos colaterais consistiram em tontura 27,5%; sonolência 21,0%; eólica 17,5%; náusea 16,0%; diarréia 9,0%; cefaléia 7,...

  8. Structural bioinformatics study of PNP from Schistosoma mansoni

    International Nuclear Information System (INIS)

    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

  9. Avaliação terapêutica do praziquantel (Embay 8440 na infecção humana pelo S. mansoni Therapeutical investigation of praziquantel in human infection due to Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Silvino Alves de Carvalho

    1984-02-01

    Full Text Available Foram tratados com praziquantel, dose oral única de 40 ou 50 mg/kg, 200 indivíduos portadores de esquistossomose mansoni, matriculados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As idades dos pacientes variavam de seis a 63 anos, sendo que 33 (16,5% eram menores de 15 anos. Os principais efeitos colaterais consistiram em tontura 27,5%; sonolência 21,0%; eólica 17,5%; náusea 16,0%; diarréia 9,0%; cefaléia 7,5%; vômito 4,0%; febre 2,0%; disenteria 1,0%; tremor 1,0%; exantema 1,0% e urticaria 0,5%. A toxicidade do medicamento foi investigada mediante a realização, pré e pós-tratamento, de exames hematimétricos, bem como de função renal (uréia e creatinina, hepática (enzimas de liberação hépato-canalicular e bilirrubinas, cardíaca (ECG e neuropsiquiátrica (EEG. Não foram encontradas nesses controles alterações relevantes que repercutissem clinicamente. O controle de cura verificou-se em 115 indivíduos, através de oito coproscopias, no período de seis meses, subseqüente ao tratamento, utilizando-se duas técnicas (HOFFMAN e KATO/KATZ para cada amostra de fezes. Dos 82 indivíduos que tiveram as oito coproscopias negativadas, 62 realizaram biópsia retal. Essa mostrou-se positiva em duas oportunidades, indicando um percentual de 3,2% de achados falsos negativos com relação às coproscopias. Os índices de cura variaram de 65,2%, nos pacientes menores de 15 anos, a 75% nos acima dessa idade. Para todas as faixas etárias a eficácia foi de 71,3%. Os resultados obtidos demonstram ter o praziquantel, nas doses empregadas, relativa eficácia no tratamento da esquistossomose mansoni, bem como ser determinante de baixos efeitos tóxico-colaterais.Two hundred patients with schistosomiasis mansoni, registered in the Infectious and Parasitic Disease Ward, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, were

  10. Human lipoprotein binding to schistosomula of schistosoma mansoni. Displacement by polyanions, parasite antigen masking, and persistence in young larvae.

    OpenAIRE

    Chiang, C. P.; Caulfield, J. P.

    1989-01-01

    It was previously shown by the authors that the binding of human low-density lipoprotein (LDL) to the surface of schistosomula inhibits the binding of human anti-schistosomal antibodies and is inhibited by suramin. Here, three questions were considered. 1) Are LDLs bound to schistosomula displaced from the membrane by polyanions? 2) Does bound LDL mask or hide antigens recognized by human anti-schistosomal antibodies? 3) Is LDL, binding capability present when the larvae enter the blood strea...

  11. Schistosoma mansoni egg glycoproteins : glycan structures and host immune responses

    NARCIS (Netherlands)

    Meevissen, Moniek Hubertina Joanna

    2012-01-01

    Schistosomes are parasitic helminths that cause chronic infections in over 200 million people in tropical and sub-tropical areas around the world. Glycoproteins from the eggs of the parasite Schistosoma mansoni induce various immune responses in the human host, including T-cell modulation and granul

  12. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs.

    Science.gov (United States)

    Smit, Cornelis H; van Diepen, Angela; Nguyen, D Linh; Wuhrer, Manfred; Hoffmann, Karl F; Deelder, André M; Hokke, Cornelis H

    2015-07-01

    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 of glycans and antigenic glycan-motifs during a range of critical stages of the complex schistosome lifecycle. We performed a longitudinal profiling study covering schistosome glycosylation throughout worm- and egg-development using a mass spectrometry-based glycomics approach. Our study revealed that during worm development N-glycans with Galβ1-4(Fucα1-3)GlcNAc (LeX) and core-xylose motifs were rapidly lost after cercariae to schistosomula transformation, whereas GalNAcβ1-4GlcNAc (LDN)-motifs gradually became abundant and predominated in adult worms. LeX-motifs were present on glycolipids up to 2 weeks of schistosomula development, whereas glycolipids with mono- and multifucosylated LDN-motifs remained present up to the adult worm stage. In contrast, expression of complex O-glycans diminished to undetectable levels within days after transformation. During egg development, a rich diversity of N-glycans with fucosylated motifs was expressed, but with α3-core fucose and a high degree of multifucosylated antennae only in mature eggs and miracidia. N-glycan antennae were exclusively LDN-based in miracidia. O-glycans in the mature eggs were also diverse and contained LeX- and multifucosylated LDN, but none of these were associated with miracidia in which we detected only the Galβ1-3(Galβ1-6)GalNAc core glycan. Immature eggs also exhibited short O-glycan core structures only, suggesting that complex fucosylated O-glycans of schistosome eggs are derived primarily from glycoproteins produced by the subshell envelope in the developed egg. Lipid glycans with multifucosylated GlcNAc repeats were present throughout egg development, but with the longer highly fucosylated

  13. Estudo da infecção esquistossomótica produzida pelas linhagens humana e silvestre do Vale do Rio Paraíba do Sul, SP (Brasil, em camundongos isogênicos Some results of schistosomiasis mansoni in inbred mice infected with human and wild rodent strains from the Paraiba do Sul River Valley, S. Paulo, Brazil

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    Othon de Carvalho Bastos

    1979-12-01

    Full Text Available Foi estudada a influência da isogenicidade de camundongos de laboratório na capacidade de penetração de cercárias de Schistosoma mansoni de linhagem humana do Vale do Rio Paraíba do Sul, SP. Foram estudados, comparativamente, aspectos da biologia e da patogenia das linhagens humana e silvestre do S. mansoni do Vale do Rio Paraíba do Sul, SP (Brasil em camundongos isogênicos. Foi vantajoso o uso de camundongos isogênicos devido a maior homogeneidade dos resultados e a maior penetração de cercárias pelo tegumento da cauda dos roedores.The behavior of a human S. mansoni strain was studied in infected, outbred mice. A comparative study was carried out to evaluate the effects of the infection in inbred mice, employing human and wild rodent strains of S. mansoni. The use of inbred mice was advantageous in that it allowed greater uniformity in the results as well as greater penetration of surrounding areas through the caudal tegmentum.

  14. Susceptibility of Argentinean Biomphalaria tenagophila and Biomphalaria straminea to infection by Schistosoma mansoni and the possibility of geographic expansion of mansoni schistosomiasis

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    Luciana Franceschi Simoes

    2013-10-01

    Full Text Available Introduction Human migration and the presence of natural vectors (mollusks of Schistosoma mansoni are the primary causes of the expansion of mansoni schistosomiasis into southern areas of South America. Water conditions are favorable for the expansion of this disease because of the extensive hydrographic network, which includes the basins of the Paraná and Uruguay rivers and favors mollusk reproduction. These rivers also aid agriculture and tourism in the area. Despite these favorable conditions, natural infection by S. mansoni has not yet been reported in Argentina, Uruguay, or Paraguay. Methods Two species of planorbid from Argentina, Biomphalaria straminea and B. tenagophila, were exposed to the miracidia of five Brazilian strains of S. mansoni. Results Biomphalaria tenagophila (Atalaya, Buenos Aires province was infected with the SJS strain (infection rate 3.3%, confirming the experimental susceptibility of this Argentinian species. Biomphalaria straminea (Rio Santa Lucía, Corrientes province was susceptible to two Brazilian strains: SJS (infection rate 6.7% and Sergipe (infection rate 6.7%. Conclusions These results demonstrate that species from Argentina have the potential to be natural hosts of S. mansoni and that the appearance of foci of mansoni schistosomiasis in Argentina is possible.

  15. Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

    OpenAIRE

    Xiao Shuhua; Shen Binggui; Utzinger Jürg; Chollet Jacques; Tanner Marcel

    2002-01-01

    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 wit...

  16. The dendritic cell-specific C-type lectin DC-SIGN is a receptor for Schistosoma mansoni egg antigens and recognizes the glycan antigen Lewis x.

    NARCIS (Netherlands)

    Die, van I.M.; Vliet, van SJ; Nyame, AK; Cummings, RD; Bank, CM; Appelmelk, B.J.; Geijtenbeek, T.B.H.; Kooijk, van Y.

    2003-01-01

    Schistosoma mansoni soluble egg antigens (SEAs) are crucially involved in modulating the host immune response to infection by S. mansoni. We report that human dendritic cells bind SEAs through the C-type lectin dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN). Monoclonal antibodies agai

  17. Schistosoma mansoni; relationship between membrane turnover rates and susceptibility to immune damage. Part of a coordinated programme on preparation of irradiated vaccines against some human diseases

    International Nuclear Information System (INIS)

    It is known that the schistosomulum of Schistosoma mansoni become refractory to damage by antibody and complement in vitro in the presence of serum, or Concanavalin A (Con A), or after contact with host tissues, presumably due to intrinsic changes in the surface membrane. This project studied the effect of dialysed fetal calf serum (DFCS) and Con A on the synthesis and turnover of individual proteins in the surface membrane using the incorporation of 14C- and 3H-labelled Arginine and the separation of the membrane proteins in SDS-PAGE. The results indicate that during the period in which schistosomules become resistant to immune attack, no qualitative alterations in electrophoretic patterns of surface proteins were observed. There was, however, a marked heterogeneity in synthesis and degradation among constituent proteins. In addition, Con A which had been shown to be effective in stimulating loss of susceptibility to immune attack, caused a slight decrease in the synthesis and turnover rate of high molecular weight proteins, whilst DFCS increased synthesis and turnover of low molecular weight proteins. This suggests that at least two processes occur in the membrane which may be related to the development of protection against immune attack. Serum might stimulate the loss of crucial antigens by accelerating their turnover making antibody attachment difficult, and Con A could be stabilizing the membrane by crosslinking large macromolecules. It is possible that in vivo both mechanisms occur to make the schistosomule surface refractory to damage

  18. 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.

  19. Investigation of the proteolytic functions of an expanded cercarial elastase gene family in Schistosoma mansoni.

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    Jessica R Ingram

    Full Text Available BACKGROUND: Cercarial elastase is the major invasive larval protease in Schistosoma mansoni, a parasitic blood fluke, and is essential for host skin invasion. Genome sequence analysis reveals a greatly expanded family of cercarial elastase gene isoforms in Schistosoma mansoni. This expansion appears to be unique to S. mansoni, and it is unknown whether gene duplication has led to divergent protease function. METHODS: Profiling of transcript and protein expression patterns reveals that cercarial elastase isoforms are similarly expressed throughout the S. mansoni life cycle. Computational modeling predicts key differences in the substrate-binding pockets of various cercarial elastase isoforms, suggesting a diversification of substrate preferences compared with the ancestral gene of the family. In addition, active site labeling of SmCE reveals that it is activated prior to exit of the parasite from its intermediate snail host. CONCLUSIONS: The expansion of the cercarial gene family in S. mansoni is likely to be an example of gene dosage. In addition to its critical role in human skin penetration, data presented here suggests a novel role for the protease in egress from the intermediate snail host. This study demonstrates how enzyme activity-based analysis complements genomic and proteomic studies, and is key in elucidating proteolytic function.

  20. Use of geospatial modeling to predict Schistosoma mansoni prevalence in Nyanza Province, Kenya.

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    Dana M Woodhall

    Full Text Available BACKGROUND: Schistosomiasis, a parasitic disease that affects over 200 million people, can lead to significant morbidity and mortality; distribution of single dose preventative chemotherapy significantly reduces disease burden. Implementation of control programs is dictated by disease prevalence rates, which are determined by costly and labor intensive screening of stool samples. Because ecological and human factors are known to contribute to the focal distribution of schistosomiasis, we sought to determine if specific environmental and geographic factors could be used to accurately predict Schistosoma mansoni prevalence in Nyanza Province, Kenya. METHODOLOGY/PRINCIPAL FINDINGS: A spatial mixed model was fit to assess associations with S. mansoni prevalence in schools. Data on S. mansoni prevalence and GPS location of the school were obtained from 457 primary schools. Environmental and geographic data layers were obtained from publicly available sources. Spatial models were constructed using ArcGIS 10 and R 2.13.0. Lower S.mansoni prevalence was associated with further distance (km to Lake Victoria, higher day land surface temperature (LST, and higher monthly rainfall totals. Altitude, night LST, human influence index, normalized difference vegetation index, soil pH, soil texture, soil bulk density, soil water capacity, population, and land use variables were not significantly associated with S. mansoni prevalence. CONCLUSIONS: Our model suggests that there are specific environmental and geographic factors that influence S. mansoni prevalence rates in Nyanza Province, Kenya. Validation and use of schistosomiasis prevalence maps will allow control programs to plan and prioritize efficient control campaigns to decrease schistosomiasis burden.

  1. Infecção natural de roedores silvestres pelo Schistosoma mansoni Natural infection of sylvatic rodents by Schistosoma mansoni

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    Tânia Maria Correa Silva

    1989-06-01

    . Miracidia isolated from the eggs recovered from Nectomys readly infected laboratory-raised Bahia strain of Biophalaria glabrata. Cercariae then obtained infected Swiss mice in a similar way as the human strains of S. mansoni kept in laboratory. Also, Swiss mice left in contact with water collections in Planalto were easily infected, which proved the transmissibility potential of the area. In conclusion: sylvatic rodents in the area of Planalto tolerate well S. mansoni infection, eliminate viable eggs in the stools, are usually infected with a strain probably of human origin and therefore may play a role in maintaining parasite cycle in the area.

  2. Protein kinase A signalling in Schistosoma mansoni cercariae and schistosomules.

    Science.gov (United States)

    Hirst, Natasha L; Lawton, Scott P; Walker, Anthony J

    2016-06-01

    Cyclic AMP (cAMP)-dependent protein kinase/protein kinase A regulates multiple processes in eukaryotes by phosphorylating diverse cellular substrates, including metabolic and signalling enzymes, ion channels and transcription factors. Here we provide insight into protein kinase A signalling in cercariae and 24h in vitro cultured somules of the blood parasite, Schistosoma mansoni, which causes human intestinal schistosomiasis. Functional mapping of activated protein kinase A using anti-phospho protein kinase A antibodies and confocal laser scanning microscopy revealed activated protein kinase A in the central and peripheral nervous system, oral-tip sensory papillae, oesophagus and excretory system of intact cercariae. Cultured 24h somules, which biologically represent the skin-resident stage of the parasite, exhibited similar activation patterns in oesophageal and nerve tissues but also displayed striking activation at the tegument and activation in a region resembling the germinal 'stem' cell cluster. The adenylyl cyclase activator, forskolin, stimulated somule protein kinase A activation and produced a hyperkinesia phenotype. The biogenic amines, serotonin and dopamine known to be present in skin also induced protein kinase A activation in somules, whereas neuropeptide Y or [Leu(31),Pro(34)]-neuropeptide Y attenuated protein kinase A activation. However, neuropeptide Y did not block the forskolin-induced somule hyperkinesia. Bioinformatic investigation of potential protein associations revealed 193 medium confidence and 59 high confidence protein kinase A interacting partners in S. mansoni, many of which possess putative protein kinase A phosphorylation sites. These data provide valuable insight into the intricacies of protein kinase A signalling in S. mansoni and a framework for further physiological investigations into the roles of protein kinase A in schistosomes, particularly in the context of interactions between the parasite and the host. PMID:26777870

  3. A loop-mediated isothermal amplification (LAMP assay for early detection of Schistosoma mansoni in stool samples: a diagnostic approach in a murine model.

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    Pedro Fernández-Soto

    2014-09-01

    Full Text Available Human schistosomiasis, mainly due to Schistosoma mansoni species, is one of the most prevalent parasitic diseases worldwide. To overcome the drawbacks of classical parasitological and serological methods in detecting S. mansoni infections, especially in acute stage of the disease, development of cost-effective, simple and rapid molecular methods is still needed for the diagnosis of schistosomiasis. A promising approach is the loop-mediated isothermal amplification (LAMP technology. Compared to PCR-based assays, LAMP has the advantages of reaction simplicity, rapidity, specificity, cost-effectiveness and higher amplification efficiency. Additionally, as results can be inspected by the naked eye, the technique has great potential for use in low-income countries.A sequence corresponding to a mitochondrial S. mansoni minisatellite DNA region was selected as a target for designing a LAMP-based method to detect S. mansoni DNA in stool samples. We used a S. mansoni murine model to obtain well defined stool and sera samples from infected mice with S. mansoni cercariae. Samples were taken weekly from week 0 to 8 post-infection and the Kato-Katz and ELISA techniques were used for monitoring the infection. Primer set designed were tested using a commercial reaction mixture for LAMP assay and an in house mixture to compare results. Specificity of LAMP was tested using 16 DNA samples from different parasites, including several Schistosoma species, and no cross-reactions were found. The detection limit of our LAMP assay (SmMIT-LAMP was 1 fg of S. mansoni DNA. When testing stool samples from infected mice the SmMIT-LAMP detected S. mansoni DNA as soon as 1 week post-infection.We have developed, for the first time, a cost-effective, easy to perform, specific and sensitive LAMP assay for early detection of S. mansoni in stool samples. The method is potentially and readily adaptable for field diagnosis and disease surveillance in schistosomiasis-endemic areas.

  4. 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.

  5. 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.

  6. Fase aguda da esquistossomose mansoni

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    Edward Tonelli

    1972-10-01

    Full Text Available O A. faz um estudo panorâmico sobre a fase aguda da esquistossomose mansoni, abordando o quadro clínico e seu diagnóstico, os exames subsidiários, o diagnóstico diferencial, a terapêutica e os aspectos evolutivos. As manifestações clinicas dos períodos de incubação, de estado e de supressão são abordados. O diagnóstico da fase aguda é baseado em dado epidemiológico, 110 exame fisico e em exames subsidiários. O dado epidemiológico. em geral, é positivo, com menção a banho infectante, comumente 30 a 40 dias antes do início do quadro clínico e ao exame físico, encontramos hipertermia (38 - 4G°C, prostração, micropoliadenia hepatomegalia dolorosa em 95%, dos casos e esplenomegalia em 70% dos casos. Os exames prioritários para o diagnóstico são o exame parasiiológico de fezes seriado, que é positivo para ovos viáveis de S. mansoni e o leucograma seriado, que, geralmente, acusa leucocitose com eosinofilia. Em caso de dúvida ou para complementação diagnostica, podemos recorrer à endoscovia retal, ao oograma e á biópsia hepática. A endoscopia acusa, comumente, mucosa hiperêmica, edemaciada, friável, granulosa, com pontos hemorrágicos e o exame colhido por punção biópsia revela, entre outros achados, granulomas na fase necrótica-exsudativa. O diagnóstico diferencial deve ser feito com as seguintes entidades clínicas: gastroenterites. febre tifóide, disenteria bacilar, amebíase aguda, salmonelose septicêrnica prolongada, devendo, ainda, figurar a tuberculose miliar, abdome agudo, a G.N.D.A., a mononucleose infecciosa, a leptospirose, a hepatite e as poaneurites. A terapeutica é baseada nos cuidados gerais, na córticoterapia e na terapêutica específica. Observamos regressão dramática do quadro toxinfeccioso. nas primeiras 24 a 48 horas com a córticoterapia (prednisona que tem duração aproximada de 7 a 10 dias. A terapêutica específica (derivado nitrotiazolico = ambilhar e derivado hidroximet

  7. Formol-ether concentration method in the diagnosis of active schistosoma mansoni in patients with detectable IHA

    Directory of Open Access Journals (Sweden)

    Al Mofarreh Mohammad

    2000-01-01

    Full Text Available Schistosomiasis is a world wide human infection. In Saudi Arabia there are multiple endemic foci. Various methods have been used to diagnose Schistosoma mansoni. We studied 1410 patients coming from S. mansoni endemic areas with detectable antibodies by indirect hemagglutination (IHA. Stool specimens were tested for S. mansoni ova by direct smear and formol-ether concentration (FEC methods. The objective of the study was to identify patients with active schistosomiasis using FEC method and a single direct smear. Twenty percent of IHA positive patients had active infection detected by FEC, while a single direct stool smear diagnosed only 2.4% (P< 0.0001. The percentage of positive FEC was significantly increasing in linear trend with IHA level. This trend wasn′t observed with direct smear examination. The current data suggest that FEC is helpful to diagnose active schistosomiasis, therefore it is recommended in IRA positive individuals.

  8. Schistosoma mansoni cercariae exploit an elastohydrodynamic coupling to swim efficiently

    CERN Document Server

    Krishnamurthy, Deepak; Bhargava, Arjun; Prakash, Manu

    2016-01-01

    The motility of many parasites is critical for the infection process of their host, as exemplified by the transmission cycle of the blood fluke Schistosoma mansoni. In their human infectious stage, immature, submillimetre-scale forms of the parasite known as cercariae swim in freshwater and infect humans by penetrating through the skin. This infection causes Schistosomiasis, a parasitic disease that is comparable to malaria in its global socio-economic impact. Given that cercariae do not feed and hence have a finite lifetime of around 12 hours, efficient motility is crucial for the parasite's survival and transmission of Schistosomiasis. However, a first-principles understanding of how cercariae swim is lacking. Via a combined experimental, theoretical and robotics based approach, we demonstrate that cercariae propel themselves against gravity by exploiting a unique elastohydrodynamic coupling. We show that cercariae beat their tail in a periodic fashion while maintaining a fixed flexibility near their poster...

  9. Pseudoneoplastic lesion of the breast caused by Schistosoma mansoni Pseudoneoplasma da mama causado pelo Schistosoma mansoni

    OpenAIRE

    Carlos Anselmo Lima; Aécio Costa Cavalcanti; Márcia Maria Macêdo Lima; Nestor Piva

    2004-01-01

    A case of a pseudoneoplastic lesion of the breast clinically and sonographically suggestive of a fibroadenoma is reported. Excisional biopsy revealed the nodule was an inflammatory process consequent to infection by Schistosoma mansoni.Relata-se um caso de uma lesão pseudoneoplásica da mama clinicamente e ultrasonograficamente sugestiva de um fibroadenoma. A biópsia excisional revelou que o nódulo tratava-se de um processo inflamatório conseqüente à infecção pelo Schistosoma mansoni.

  10. Pseudoneoplastic lesion of the breast caused by Schistosoma mansoni Pseudoneoplasma da mama causado pelo Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Carlos Anselmo Lima

    2004-02-01

    Full Text Available A case of a pseudoneoplastic lesion of the breast clinically and sonographically suggestive of a fibroadenoma is reported. Excisional biopsy revealed the nodule was an inflammatory process consequent to infection by Schistosoma mansoni.Relata-se um caso de uma lesão pseudoneoplásica da mama clinicamente e ultrasonograficamente sugestiva de um fibroadenoma. A biópsia excisional revelou que o nódulo tratava-se de um processo inflamatório conseqüente à infecção pelo Schistosoma mansoni.

  11. Discriminating acute from chronic human schistosomiasis mansoni.

    Science.gov (United States)

    Beck, Lílian; Van-Lüme, Daniele S M; Souza, Joelma R; Domingues, Ana L C; Favre, Tereza; Abath, Frederico G C; Montenegro, Silvia M L

    2008-01-01

    Specific immunoglobulin (IgA, IgG and IgM) responses to different antigen targets (soluble eggs antigen--SEA, soluble worm adult protein--SWAP and keyhole limpet hole--KLH) were measured by enzyme linked immunosorbent assay (ELISA) in patients with acute and chronic schistosomiasis, as well as patients without schistosomiasis. SEA IgA and KLH IgM presented high discriminatory powers to distinguish acute from chronic schistosomiasis, with calculated areas under the curve (AUCs) of 0.88 and 0.82, respectively, obtained from receiver operating characteristic (ROC) curve. On the other hand, these tests, particularly SEA IgA were not useful to distinguish schistosomiasis (including the acute and chronic forms) from individuals without this disease, but infected with other intestinal parasites (Ascaris lumbricoides, Trichuris trichiura and hookworm). By contrast, SWAP IgG and SEA IgG were able to discriminate schistosomiasis patients from healthy individuals and patients infected with other parasites (AUCs of 0.96 and 0.85, respectively). Thus, it is possible to use a combination of serological tests, such as SEA IgA and SWAP IgG, to simultaneously establish the diagnosis of schistosomiasis and discriminate the acute from the chronic forms of the disease.

  12. Characterization of the phytochelatin synthase of Schistosoma mansoni.

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    Debalina Ray

    2011-05-01

    Full Text Available Treatment for schistosomiasis, which is responsible for more than 280,000 deaths annually, depends exclusively on the use of praziquantel. Millions of people are treated annually with praziquantel and drug resistant parasites are likely to evolve. In order to identify novel drug targets the Schistosoma mansoni sequence databases were queried for proteins involved in glutathione metabolism. One potential target identified was phytochelatin synthase (PCS. Phytochelatins are oligopeptides synthesized enzymatically from glutathione by PCS that sequester toxic heavy metals in many organisms. However, humans do not have a PCS gene and do not synthesize phytochelatins. In this study we have characterized the PCS of S. mansoni (SmPCS. The conserved catalytic triad of cysteine-histidine-aspartate found in PCS proteins and cysteine proteases is also found in SmPCS, as are several cysteine residues thought to be involved in heavy metal binding and enzyme activation. The SmPCS open reading frame is considerably extended at both the N- and C-termini compared to PCS from other organisms. Multiple PCS transcripts are produced from the single encoded gene by alternative splicing, resulting in both mitochondrial and cytoplasmic protein variants. Expression of SmPCS in yeast increased cadmium tolerance from less than 50 µM to more than 1,000 µM. We confirmed the function of SmPCS by identifying PCs in yeast cell extracts using HPLC-mass spectrometry. SmPCS was found to be expressed in all mammalian stages of worm development investigated. Increases in SmPCS expression were seen in ex vivo worms cultured in the presence of iron, copper, cadmium, or zinc. Collectively, these results indicate that SmPCS plays an important role in schistosome response to heavy metals and that PCS is a potential drug target for schistosomiasis treatment. This is the first characterization of a PCS from a parasitic organism.

  13. Schistosoma mansoni Infection in Ugandan Men Is Associated with Increased Abundance and Function of HIV Target Cells in Blood, but Not the Foreskin: A Cross-sectional Study.

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    Jessica L Prodger

    Full Text Available Schistosoma mansoni infection has been associated with an increased HIV prevalence in humans and SHIV incidence in primate models. We hypothesized that immune activation from this gastrointestinal mucosa infection would increase highly HIV-susceptible CD4 T cell subsets in the blood and the foreskin through common mucosal homing.Foreskin tissue and blood were obtained from 34 HIV- and malaria-uninfected Ugandan men who volunteered for elective circumcision, 12 of whom were definitively positive for S. mansoni eggs in stool and 12 definitively negative for both S. mansoni eggs and worm antigen. Tissue and blood T cell subsets were characterized by flow cytometry and immunohistochemistry (IHC. Th17 and Th1 cells from both the blood and foreskin expressed higher levels of CCR5 and were more activated than other CD4 T cell subsets. S. mansoni-infected men had a higher frequency of systemic Th1 cells (22.9 vs. 16.5% of blood CD4 T cells, p<0.05, Th17 cells (2.3 vs. 1.5%, p<0.05, and Th22 cells (0.5 vs. 0.3%, p<0.01 than uninfected men. Additionally, Th17 cells in the blood of S. mansoni-infected men demonstrated enhanced function (28.1 vs. 16.3% producing multiple cytokines, p = 0.046. However, these immune alterations were not observed in foreskin tissue.S. mansoni infection was associated with an increased frequency of highly HIV-susceptible Th1, Th17 and Th22 cell subsets in the blood, but these T cell immune differences did not extend to the foreskin. S. mansoni induced changes in T cell immunology mediated through the common mucosal immune system are not likely to increase HIV susceptibility in the foreskin.

  14. Towards an Understanding of the Function of the Phytochelatin Synthase of Schistosoma mansoni

    Science.gov (United States)

    Rigouin, Coraline; Nylin, Elyse; Cogswell, Alexis A.; Schaumlöffel, Dirk; Dobritzsch, Dirk; Williams, David L.

    2013-01-01

    Phytochelatin synthase (PCS) is a protease-like enzyme that catalyzes the production of metal chelating peptides, the phytochelatins, from glutathione (GSH). In plants, algae, and fungi phytochelatin production is important for metal tolerance and detoxification. PCS proteins also function in xenobiotic metabolism by processing GSH S-conjugates. The aim of the present study is to elucidate the role of PCS in the parasitic worm Schistosoma mansoni. Recombinant S. mansoni PCS proteins expressed in bacteria could both synthesize phytochelatins and hydrolyze various GSH S-conjugates. We found that both the N-truncated protein and the N- and C-terminal truncated form of the enzyme (corresponding to only the catalytic domain) work through a thiol-dependant and, notably, metal-independent mechanism for both transpeptidase (phytochelatin synthesis) and peptidase (hydrolysis of GSH S-conjugates) activities. PCS transcript abundance was increased by metals and xenobiotics in cultured adult worms. In addition, these treatments were found to increase transcript abundance of other enzymes involved in GSH metabolism. Highest levels of PCS transcripts were identified in the esophageal gland of adult worms. Taken together, these results suggest that S. mansoni PCS participates in both metal homoeostasis and xenobiotic metabolism rather than metal detoxification as previously suggested and that the enzyme may be part of a global stress response in the worm. Because humans do not have PCS, this enzyme is of particular interest as a drug target for schistosomiasis. PMID:23383357

  15. Towards an understanding of the function of the phytochelatin synthase of Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Coraline Rigouin

    Full Text Available Phytochelatin synthase (PCS is a protease-like enzyme that catalyzes the production of metal chelating peptides, the phytochelatins, from glutathione (GSH. In plants, algae, and fungi phytochelatin production is important for metal tolerance and detoxification. PCS proteins also function in xenobiotic metabolism by processing GSH S-conjugates. The aim of the present study is to elucidate the role of PCS in the parasitic worm Schistosoma mansoni. Recombinant S. mansoni PCS proteins expressed in bacteria could both synthesize phytochelatins and hydrolyze various GSH S-conjugates. We found that both the N-truncated protein and the N- and C-terminal truncated form of the enzyme (corresponding to only the catalytic domain work through a thiol-dependant and, notably, metal-independent mechanism for both transpeptidase (phytochelatin synthesis and peptidase (hydrolysis of GSH S-conjugates activities. PCS transcript abundance was increased by metals and xenobiotics in cultured adult worms. In addition, these treatments were found to increase transcript abundance of other enzymes involved in GSH metabolism. Highest levels of PCS transcripts were identified in the esophageal gland of adult worms. Taken together, these results suggest that S. mansoni PCS participates in both metal homoeostasis and xenobiotic metabolism rather than metal detoxification as previously suggested and that the enzyme may be part of a global stress response in the worm. Because humans do not have PCS, this enzyme is of particular interest as a drug target for schistosomiasis.

  16. Towards an understanding of the function of the phytochelatin synthase of Schistosoma mansoni.

    Science.gov (United States)

    Rigouin, Coraline; Nylin, Elyse; Cogswell, Alexis A; Schaumlöffel, Dirk; Dobritzsch, Dirk; Williams, David L

    2013-01-01

    Phytochelatin synthase (PCS) is a protease-like enzyme that catalyzes the production of metal chelating peptides, the phytochelatins, from glutathione (GSH). In plants, algae, and fungi phytochelatin production is important for metal tolerance and detoxification. PCS proteins also function in xenobiotic metabolism by processing GSH S-conjugates. The aim of the present study is to elucidate the role of PCS in the parasitic worm Schistosoma mansoni. Recombinant S. mansoni PCS proteins expressed in bacteria could both synthesize phytochelatins and hydrolyze various GSH S-conjugates. We found that both the N-truncated protein and the N- and C-terminal truncated form of the enzyme (corresponding to only the catalytic domain) work through a thiol-dependant and, notably, metal-independent mechanism for both transpeptidase (phytochelatin synthesis) and peptidase (hydrolysis of GSH S-conjugates) activities. PCS transcript abundance was increased by metals and xenobiotics in cultured adult worms. In addition, these treatments were found to increase transcript abundance of other enzymes involved in GSH metabolism. Highest levels of PCS transcripts were identified in the esophageal gland of adult worms. Taken together, these results suggest that S. mansoni PCS participates in both metal homoeostasis and xenobiotic metabolism rather than metal detoxification as previously suggested and that the enzyme may be part of a global stress response in the worm. Because humans do not have PCS, this enzyme is of particular interest as a drug target for schistosomiasis.

  17. Phytol, a diterpene alcohol from chlorophyll, as a drug against neglected tropical disease Schistosomiasis mansoni.

    Directory of Open Access Journals (Sweden)

    Josué de Moraes

    Full Text Available BACKGROUND: Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. METHODS AND FINDINGS: In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL. Additionally, phytol at sublethal doses (25 µg/mL reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6% and the frequency of immature eggs (oogram pattern was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. CONCLUSIONS: The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy.

  18. Phytol, a Diterpene Alcohol from Chlorophyll, as a Drug against Neglected Tropical Disease Schistosomiasis Mansoni

    Science.gov (United States)

    de Moraes, Josué; de Oliveira, Rosimeire N.; Costa, Jéssica P.; Junior, Antonio L. G.; de Sousa, Damião P.; Freitas, Rivelilson M.; Allegretti, Silmara M.; Pinto, Pedro L. S.

    2014-01-01

    Background Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. Methods and findings In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL). Additionally, phytol at sublethal doses (25 µg/mL) reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg) administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6%) and the frequency of immature eggs (oogram pattern) was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. Conclusions The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy. PMID:24392173

  19. Intermediate hosts of schistosoma mansoni in Brazil

    OpenAIRE

    Omar dos Santos Carvalho

    1992-01-01

    The Brazilian planorbidical chart is slowly but progressively been increased by new data. Distribution of vector species of Schistosoma mansoni, according to Paraense, 1986, may be thus resumed: Biomphalaria glabrata - delimited by paralells 13 and 21-S and meridians 39 and 45-W, area of greater dominance (Southerst Bahia, oriental half of Minas Gerais and Espírito Santo). It is observed along the coast line of the state of Sergipe, Alagoas, Pernambuco, Paraíba and Rio Grande do Norte. Starti...

  20. Biological implications of the phenotypic plasticity in the Schistosoma mansoni - Nectomys squamipes model Implicações biológicas da plasticidade fenotípica no modelo Schistosoma mansoni - Nectomys squamipes

    Directory of Open Access Journals (Sweden)

    Elaine Machado Martinez

    2008-08-01

    Full Text Available The water-rat Nectomys squamipes is mostly important non-human host in schistosomiasis mansoni transmission in Brazil, due to its susceptibility, high abundance and water-contact pattern. During experimental infection of N. squamipes with Schistosoma mansoni, adult worms show phenotypic plasticity. This finding led us to investigate whether biological behavior is also affected. This was assessed comparing the biological characteristics of four S. mansoni strains: BE (State of Belém do Pará, CE (State of Pernambuco, CMO (State of Rio Grande do Norte and SJ (State of São Paulo using laboratory-bred N. squamipes. The infection was monitored by determination of the pre-patent period, fecal egg output, egg viability, intestinal egg count and, infectivity rate. No biological modification was observed in these parameters. Overall results highlight that N. squamipes was susceptible to several S. mansoni strains, suggesting that it might contribute to the maintenance of schistosomiasis mansoni in Brazil.O rato d´água Nectomys squamipes é importante transmissor não-humano da esquistossomose. Durante a infecção experimental em N. squamipes, os vermes adultos apresentam plasticidade fenotípica. Esses achados levaram-nos a investigar se os aspectos biológicos também são afetados. Foram comparadas as características biológicas de quatro cepas de S. mansoni: BE (Estado de Belém do Pará, CM (Estado de Pernambuco, CMO (Estado do Rio Grande do Norte e SJ (Estado de São Paulo, utilizando como modelo experimental N. squamipes criados e mantidos em laboratório. A infecção foi monitorada para a determinação do período pré-patente, eliminação de ovos nas fezes, viabilidade dos ovos, contagem de ovos retidos no intestino e infectividade. Nenhuma modificação biológica foi observada nesses parâmetros. Os resultados sugerem que o N. squamipes é susceptível a várias cepas de S. mansoni, contribuindo para a manutenção da esquistossomose

  1. Activity of epiisopiloturine against Schistosoma mansoni.

    Science.gov (United States)

    Veras, L M; Guimaraes, M A; Campelo, Y D; Vieira, M M; Nascimento, C; Lima, D F; Vasconcelos, L; Nakano, E; Kuckelhaus, S S; Batista, M C; Leite, J R; Moraes, J

    2012-01-01

    Schistosomiasis, caused by blood flukes of the genus Schistosoma, still imposes a considerable public health burden on large parts of the world. The control of this disease depends almost exclusively on the drug praziquantel, and there are no alternative drugs in sight. Natural compounds have recently attracted significant attention due to their relevance to parasitic infection and potential development into new therapeutic agents. Epiisopiloturine is an imidazole alkaloid isolated from the leaves of Pilocarpus microphyllus (Rutaceae), a native plant from Brazil. Here, we report the in vitro effect of this drug on the survival time of Schistosoma mansoni of different ages, such as 3 h old and 1, 3, 5, and 7 days old schistosomula, 49-day-old adults, and on egg output by adult worms. Epiisopiloturine at a concentration of 300 μg/mL caused the death of all schistosomula within 120 h. Extensive tegumental alterations and death were observed when adult schistosomes had been exposed to 150 μg/mL of the epiisopiloturine. At the highest sub-lethal dose of alkaloid (100 μg/mL), a 100% reduction in egg laying of paired adult worms was observed. Additionally, epiisopiloturine showed selective antischistosomal activity and exhibited no cytotoxicity to mammalian cells. This report provides the first evidence that epiisopiloturine is able to kill S. mansoni of different ages and inhibit worm egg laying. PMID:22420337

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Pseudoneoplastic lesion of the breast caused by Schistosoma mansoni

    OpenAIRE

    Lima Carlos Anselmo; Cavalcanti Aécio Costa; Lima Márcia Maria Macêdo; Piva Nestor

    2004-01-01

    A case of a pseudoneoplastic lesion of the breast clinically and sonographically suggestive of a fibroadenoma is reported. Excisional biopsy revealed the nodule was an inflammatory process consequent to infection by Schistosoma mansoni.

  4. Schistosoma mansoni heat shock protein 70 elicits an early humoral immune response in S. mansoni infected baboons

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    Herminia Y Kanamura

    2002-07-01

    Full Text Available A study was undertaken to search for DNA recombinant Schistosoma mansoni proteins responsible for eliciting an antibody response from the host at a very early phase after infection. A S. mansoni adult worm cDNA expression library was screened using pooled sera from baboons with four weeks of infection. Based on their specific reactivity with the S. mansoni infected sera and no reactivity when tested against the pre-infection sera from the same baboons, four clones were selected for further studies. Sequence analysis revealed that they were homologous to the S. mansoni heat shock protein 70 (hsp70. The insert sizes of the four selected clones varied from 1150 to 2006 bp. The preliminary characterization for antibody reactivity against a panel of baboon sera showed that the longest clone was the most reactive, eight out of eight acute and three out of four chronic sera reacting positively to this clone. The shortest clone was the least reactive. Our results suggest that the S. mansoni hsp70 elicits an early and strong antibody response in baboons and that antibodies to this protein can be detected in chronically infected animals. Therefore S. mansoni hsp70 may be a valid target for immunodiagnosis. However further studies are needed to identify the portion of the hsp70 that best fits the requirements for a valuable diagnostic antigen.

  5. Molecular aspects of Schistosoma mansoni female maturation

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    Ana Lúcia Moraes Giannini

    1995-04-01

    Full Text Available Incubation of total protein extracts of Schistosoma mansoni with 3H 17-beta-estradiol and 20-hydroxyecdysone, revealed steroid binding proteins in both, male and female worms. The interaction of nuclear proteins with restriction fragments of the gender and stage-specific gene F-10 was investigated using the "Band-Shift" technique. Distinct male and female nuclear proteins bound to the fragments of this gene. Among the nuclear proteins, only those rich in cysteine residues bound to DNA. In vitro incubation of live worms with the estrogen antagonist Tamoxifen, altered the pattern of the DNA binding proteins, producing in females, a band profile similar to that obtained with male worm protein extracts. When Tamoxifen was injected into schistosome infected mice, the eggs produced by females presented an abnormal morphology, compatible with non-viable eggs. These results suggest that the regulation of transcription of the F-10 gene might involve steroid receptors.

  6. Intermediate hosts of schistosoma mansoni in Brazil

    Directory of Open Access Journals (Sweden)

    Omar dos Santos Carvalho

    1992-01-01

    Full Text Available The Brazilian planorbidical chart is slowly but progressively been increased by new data. Distribution of vector species of Schistosoma mansoni, according to Paraense, 1986, may be thus resumed: Biomphalaria glabrata - delimited by paralells 13 and 21-S and meridians 39 and 45-W, area of greater dominance (Southerst Bahia, oriental half of Minas Gerais and Espírito Santo. It is observed along the coast line of the state of Sergipe, Alagoas, Pernambuco, Paraíba and Rio Grande do Norte. Starting from there, it is found towards the southwest, in the direction to the Sao Francisco River and South-Center of Minas Gerais. Isolated population may be observed in other states. Its presence is probably, associated to the transmission of schistosomiasis in all areas where it occurs. B. tenagophila - extends it self through a wide strip of coast-line the South of Bahia (17-45"S, 39-15'W, RS(33-41'S, 53-27'W. In Sao Paulo and Rio Grande do Sul states it is found further inland. It is important in schistosomiasis transmission in the Paraíba valley (SP. Isolated populations are observed in the Federal District and Minas Gerais state. B. straminea - better adapter species to climatic variation, having a more dense ditribution in the northeast (41-Wand 110-S, south of Bahia and northeast of Minas Gerais (150 and 180-S, 400 and 440-W It is less susceptible than B. glabrata, being however the most important responsible for the transmission of S. mansoni in the northeast, chiefly in the northeastern dry area, where it is almost the only transmissive species.

  7. Structural studies of Schistosoma mansoni adenylate kinases

    Energy Technology Data Exchange (ETDEWEB)

    Marques, I.A. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil); Pereira, H.M.; Garrat, R.C. [Universidade de Sao Paulo (USP-SC), Sao Carlos, SP (Brazil)

    2012-07-01

    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)

  8. SmTRC1, a novel Schistosoma mansoni DNA transposon, discloses new families of animal and fungi transposons belonging to the CACTA superfamily

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    Verjovski-Almeida Sergio

    2006-11-01

    Full Text Available Abstract Background The CACTA (also called En/Spm superfamily of DNA-only transposons contain the core sequence CACTA in their Terminal Inverted Repeats (TIRs and so far have only been described in plants. Large transcriptome and genome sequence data have recently become publicly available for Schistosoma mansoni, a digenetic blood fluke that is a major causative agent of schistosomiasis in humans, and have provided a comprehensive repository for the discovery of novel genes and repetitive elements. Despite the extensive description of retroelements in S. mansoni, just a single DNA-only transposon belonging to the Merlin family has so far been reported in this organism. Results We describe a novel S. mansoni transposon named SmTRC1, for S. mansoni Transposon Related to CACTA 1, an element that shares several characteristics with plant CACTA transposons. Southern blotting indicates approximately 30–300 copies of SmTRC1 in the S. mansoni genome. Using genomic PCR followed by cloning and sequencing, we amplified and characterized a full-length and a truncated copy of this element. RT-PCR using S. mansoni mRNA followed by cloning and sequencing revealed several alternatively spliced transcripts of this transposon, resulting in distinct ORFs coding for different proteins. Interestingly, a survey of complete genomes from animals and fungi revealed several other novel TRC elements, indicating new families of DNA transposons belonging to the CACTA superfamily that have not previously been reported in these kingdoms. The first three bases in the S. mansoni TIR are CCC and they are identical to those in the TIRs of the insects Aedes aegypti and Tribolium castaneum, suggesting that animal TRCs may display a CCC core sequence. Conclusion The DNA-only transposable element SmTRC1 from S. mansoni exhibits various characteristics, such as generation of multiple alternatively-spliced transcripts, the presence of terminal inverted repeats at the extremities of

  9. Synergy of Omeprazole and Praziquantel In Vitro Treatment against Schistosoma mansoni Adult Worms

    Science.gov (United States)

    Anderson, Leticia; Venancio, Thiago M.; Nakaya, Helder I.; Miyasato, Patrícia A.; Rofatto, Henrique K.; Zerlotini, Adhemar; Nakano, Eliana; Oliveira, Guilherme; Verjovski-Almeida, Sergio

    2015-01-01

    Background Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel (PZQ), and the selection of resistant worms under repeated treatment is a concern. Therefore, there is a pressing need to understand the molecular effects of PZQ on schistosomes and to investigate alternative or synergistic drugs against schistosomiasis. Methodology We used a custom-designed Schistosoma mansoni expression microarray to explore the effects of sublethal doses of PZQ on large-scale gene expression of adult paired males and females and unpaired mature females. We also assessed the efficacy of PZQ, omeprazole (OMP) or their combination against S. mansoni adult worms with a survival in vitro assay. Principal Findings We identified sets of genes that were affected by PZQ in paired and unpaired mature females, however with opposite gene expression patterns (up-regulated in paired and down-regulated in unpaired mature females), indicating that PZQ effects are heavily influenced by the mating status. We also identified genes that were similarly affected by PZQ in males and females. Functional analyses of gene interaction networks were performed with parasite genes that were differentially expressed upon PZQ treatment, searching for proteins encoded by these genes whose human homologs are targets of different drugs used for other diseases. Based on these results, OMP, a widely prescribed proton pump inhibitor known to target the ATP1A2 gene product, was chosen and tested. Sublethal doses of PZQ combined with OMP significantly increased worm mortality in vitro when compared with PZQ or OMP alone, thus evidencing a synergistic effect. Conclusions Functional analysis of gene interaction networks is an important approach that can point to possible novel synergistic drug candidates. We demonstrated the potential of this strategy by showing that PZQ in combination with OMP displayed increased efficiency against S. mansoni adult worms in vitro when compared with

  10. Experimental evidence and ecological perspectives for the adaptation of Schistosoma mansoni Sambon, 1907 (Digenea: Schistosomatidae to a wild host, the water-rat, Nectomys squamipes Brants, 1827 (Rodentia: Sigmodontinae

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    Paulo Sérgio D'Andrea

    2002-10-01

    Full Text Available Due to the semi aquatic habits and the overlap of the geographical distribution of the water-rat, Nectomys spp., with schistosomiasis endemic areas, these wild rodents are very likely to acquire Schistosoma mansoni infection in their daily activities. The role of the water-rat in the S. mansoni cycle would be substantiated if one could prove that these rodents acquire the parasite during their own activity time, a completely independent time schedule of human activities. To pursue this goal, we performed two field experiments in the municipality of Sumidouro, State of Rio de Janeiro, Brazil, a schistosomiasis endemic area where N. squamipes is found naturally infected. One experiment was devised as a series of observations of activity time of the water-rat. The other experiment was a test of the occurrence of late transmission of S. mansoni to the water-rat. The daily activity pattern showed that the water-rat is active chiefly just after sunset. At both diurnal and late exposition essays the water-rat sentinels got infected by S. mansoni. These findings clarify ecological and behavioral components necessary to the adaptation of S. mansoni to the water-rat as a non human definitive host and the existence of a transmission cycle involving this animals as a reservoir.

  11. Protein kinase C and extracellular signal-regulated kinase regulate movement, attachment, pairing and egg release in Schistosoma mansoni.

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    Margarida Ressurreição

    2014-06-01

    Full Text Available Protein kinases C (PKCs and extracellular signal-regulated kinases (ERKs are evolutionary conserved cell signalling enzymes that coordinate cell function. Here we have employed biochemical approaches using 'smart' antibodies and functional screening to unravel the importance of these enzymes to Schistosoma mansoni physiology. Various PKC and ERK isotypes were detected, and were differentially phosphorylated (activated throughout the various S. mansoni life stages, suggesting isotype-specific roles and differences in signalling complexity during parasite development. Functional kinase mapping in adult worms revealed that activated PKC and ERK were particularly associated with the adult male tegument, musculature and oesophagus and occasionally with the oesophageal gland; other structures possessing detectable activated PKC and/or ERK included the Mehlis' gland, ootype, lumen of the vitellaria, seminal receptacle and excretory ducts. Pharmacological modulation of PKC and ERK activity in adult worms using GF109203X, U0126, or PMA, resulted in significant physiological disturbance commensurate with these proteins occupying a central position in signalling pathways associated with schistosome muscular activity, neuromuscular coordination, reproductive function, attachment and pairing. Increased activation of ERK and PKC was also detected in worms following praziquantel treatment, with increased signalling associated with the tegument and excretory system and activated ERK localizing to previously unseen structures, including the cephalic ganglia. These findings support roles for PKC and ERK in S. mansoni homeostasis, and identify these kinase groups as potential targets for chemotherapeutic treatments against human schistosomiasis, a neglected tropical disease of enormous public health significance.

  12. 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.

  13. Infecção natural de roedores silvestres pelo Schistosoma mansoni Natural infection of sylvatic rodents by Schistosoma mansoni

    OpenAIRE

    Tânia Maria Correa Silva; Zilton A. Andrade

    1989-01-01

    No município baiano de Planalto, 47% dos roedores silvestres capturados (Nectomys) estavam infectados pelo Schistosoma mansoni, enquanto a prevalência desta infecção na população humana da área era de 3,26%. Os roedores habitam zonas peridomiciliares, têm hábitos aquáticos e eliminam ovos viáveis do S. mansoni. Albergam número variável de vermes e formam granulomas periovulares pequenos, principalmente no fígado e intestinos, sem fibrose hepática importante ou sinais de hipertensão porta. A d...

  14. 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.

  15. In vitro and in vivo studies of the effect of artemether on Schistosoma mansoni.

    OpenAIRE

    Xiao, S H; Catto, B A

    1989-01-01

    To determine whether artemether, a derivative of the antimalarial agent qinghaosu, is therapeutically active against Schistosoma mansoni, we determined the in vitro, in vivo, and histopathologic effects of the drug on S. mansoni worms. In vitro, toxic effects of artemether on S. mansoni were not seen at concentrations of less than 100 micrograms/ml. However, in vivo, 30 and 50% reductions in the lengths of male and female worms, respectively, were observed 14 days after treatment. By 56 days ...

  16. Schistosoma mansoni proteins attenuate gastrointestinal motility disturbances during experimental colitis in mice

    Institute of Scientific and Technical Information of China (English)

    Nathalie; E; Ruyssers; Benedicte; Y; De; Winter; Joris; G; De; Man; Natacha; D; Ruyssers; Ann; J; Van; Gils; Alex; Loukas; Mark; S; Pearson; Joel; V; Weinstock; Paul; A; Pelckmans; Tom; G; Moreels

    2010-01-01

    AIM:To investigate the therapeutic effect of Schistosoma mansoni(S.mansoni) soluble worm proteins on gastrointestinal motility disturbances during experimental colitis in mice. METHODS:Colitis was induced by intrarectal injection of trinitrobenzene sulphate(TNBS) and 6 h later,mice were treated ip with S.mansoni proteins.Experiments were performed 5 d after TNBS injection.Inflammationwas quantified using validated inflammation parameters. Gastric emptying and geometric center were measured to assess in vivo...

  17. Effect of maternal Schistosoma mansoni infection and praziquantel treatment during pregnancy on Schistosoma mansoni infection and immune responsiveness among offspring at age five years.

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    Robert Tweyongyere

    Full Text Available Offspring of Schistosoma mansoni-infected women in schistosomiasis-endemic areas may be sensitised in-utero. This may influence their immune responsiveness to schistosome infection and schistosomiasis-associated morbidity. Effects of praziquantel treatment of S. mansoni during pregnancy on risk of S. mansoni infection among offspring, and on their immune responsiveness when they become exposed to S. mansoni, are unknown. Here we examined effects of praziquantel treatment of S. mansoni during pregnancy on prevalence of S. mansoni and immune responsiveness among offspring at age five years.In a trial in Uganda (ISRCTN32849447, http://www.controlled-trials.com/ISRCTN32849447/elliott, offspring of women treated with praziquantel or placebo during pregnancy were examined for S. mansoni infection and for cytokine and antibody responses to SWA and SEA, as well as for T cell expression of FoxP3, at age five years.Of the 1343 children examined, 32 (2.4% had S. mansoni infection at age five years based on a single stool sample. Infection prevalence did not differ between children of treated or untreated mothers. Cytokine (IFNγ, IL-5, IL-10 and IL-13 and antibody (IgG1, Ig4 and IgE responses to SWA and SEA, and FoxP3 expression, were higher among infected than uninfected children. Praziquantel treatment of S. mansoni during pregnancy had no effect on immune responses, with the exception of IL-10 responses to SWA, which was higher in offspring of women that received praziquantel during pregnancy than those who did not.We found no evidence that maternal S. mansoni infection and its treatment during pregnancy influence prevalence and intensity of S. mansoni infection or effector immune response to S. mansoni infection among offspring at age five years, but the observed effects on IL-10 responses to SWA suggest that maternal S. mansoni and its treatment during pregnancy may affect immunoregulatory responsiveness in childhood schistosomiasis. This might have

  18. Dot-dye-immunoassay for the diagnosis of schistosomiasis mansoni

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    Ana Lúcia Teles Rabello

    1992-06-01

    Full Text Available A new serological assay dot-dye-immunoassay (dot-DIA was evaluated for the diagnosis of schistosomiasis mansoni. This method consist of four steps: (a biding of antigens to a nitrocellulose membrane (NC; (b blocking of free sites of the NC; (c incubation in specific primary antibody; (d detection of primary antibody reactivity by color development using second antibody coupled to textile dyes. Sera from 82 individuals, 61 with Schistosoma mansoni eggs in the stool and 21 stool negative were tested by ELISA, dot-ELISA, and dotDIA. A high level of agreement between the methods tested was observed for all sera tested: ELISA x dot-ELISA: 95.1%, ELISA x dot-DIA: 92.7% and dot-ELISA x dot-DIA: 97.6%. In this study, dot-DIA proved to be a feasible, sensitive, rapid and practical test for the diagnosis of shcistosomiasis.

  19. Forma aguda ou toxêmica da esquistossomose mansoni Acute or toxemic form of mansoni's schistosomiasis

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    Jayme Neves

    1992-01-01

    Full Text Available The acute toxemic form of schistosomiasis mansoni is studied under anatomic and clinical point of view, according to classification made by Neves, Raso and Bagliolo in 1975. The first phase is characterized by the following facts: cutaneous (immediate and late manifestations; high fever or in progressive elevation; intense diaphoresis abdominal disconfort; intense acquous diarrhea; dehidratation; loss of weight, dry cough; painful hepatosplenomegaly; discreet lymphademegaly, progressive increase of blood leucocytes and eosinophisles; radiological pulmonary alterations; absence of alterations in serum protein and hepatic functional tests; the hepatic function byopsy shows focus of acute hepatitis. The second stage or properly named toxemic period was clinically characterized by the neat aggravation of the previously observed phenomena. At last, the evolutive course of the disease has implication derived not only of the worm's presence, but from the intense dissemination of eggs in the tissue. In the pre-laying phase one studied the forms of cercarian dermatitis, prodromic and innapparent. In the post laying phase, the properly named acute toxemic form, with its types: pseudocholeraic, pseudotyphous, pseudodysenteric-bacillary, pseudonophritic, pseudoenterovirotic, the reactivated, the ischemic enterocolitis and others; whenever possible clinical and anatomic correlation will be made.

  20. A potential vector of Schistosoma mansoni in Uruguay Um vetor potencial do Schistosoma mansoni no Uruguai

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    W. Lobato Paraense

    1989-09-01

    Full Text Available Susceptibily experiments were carried out with a Biomphalaria straminea-like planorbid snail (Biomphalaria aff. straminea, species inquirenda from Espinillar, near Salto (Uruguay, in the area of the Salto Grande reservoir, exposed individually to 5 miracidia of Schistosoma mansoni (SJ2 and BH2 strains. Of 130 snails exposed to the SJ2 strain, originally infective to Biomphalaria tenagophila, 30 became infected (23%. The prepatent (precercaria period ranged from 35 to 65 days. The cercarial output was irregular, following no definite pattern, varying from 138 to 76,075 per snail (daily average 4.3 to 447.5 and ending up with death. Three specimens that died, without having shed cercarie, on days 69 (2 and 80 after exposure to miracidia, had developing secondary sporocysts in their tissues, justifying the prospect of a longer precercarial period in these cases. In a control group of 120 B. teangophila, exposed to the SJ2 strain, 40 became infected, showing an infection rate (33.3% not significantly different from that of the Espinillar snail (X [raised to the power of] 2 = 3.26. No cercarie were produced by any of the Espinilar snails exposed to miracidia of the BH2 strain, originally infective to Biomphalaria glabrata. Four specimens showed each a primary sporocyst in one tentacle, which disappeared between 15 and 25 days post-exposure, and two others died with immature, very slender sporocysts in their tissues on days 36 and 54. In a control group of 100 B. glabrata exposed to BH2 miracidia, 94 shed cercariae (94% and 6 remained negative. Calculation of Frandsen's (1979a, b TCP/100 index shows that "Espinillar Biomphalaria-SJ2 S. mansoni" is a vector-parasite "compatible" combination. Seeing that tenagophila-borne schistosomiasis is prevalent in Rio de Janeiro and São Paulo states and has recently spread sothwards to Santa Catarina state, and the range of B. tenagophila overlaps taht of the Espinillar Biomphalaria, the possibility of

  1. Preliminary analysis of miRNA pathway in Schistosoma mansoni.

    Science.gov (United States)

    Gomes, Matheus S; Cabral, Fernanda J; Jannotti-Passos, Liana K; Carvalho, Omar; Rodrigues, Vanderlei; Baba, Elio H; Sá, Renata G

    2009-03-01

    RNA silencing refers to a series of nuclear and cytoplasmatic processes involved in the post-transcriptional regulation of gene expression or post-transcriptional gene silencing (PTGS), either by sequence-specific mRNA degradation or by translational arrest. The best characterized small RNAs are microRNAs (miRNAs), which predominantly perform gene silencing through post-transcriptional mechanisms. In this work we used bioinformatic approaches to identify the parasitic trematode Schistosoma mansoni sequences that are similar to enzymes involved in the post-transcriptional gene silencing mediated by miRNA pathway. We used amino acid sequences of well-known proteins involved in the miRNA pathway against S. mansoni genome and transcriptome databases identifying a total of 13 putative proteins in the parasite. In addition, the transcript levels of SmDicer1 and SmAgo2/3/4 were identified by qRT-PCR using cercariae, adult worms, eggs and in vitro cultivated schistosomula. Our results showed that the SmDicer1 and SmAgo2/3/4 are differentially expressed during schistosomula development, suggesting that the miRNA pathway is regulated at the transcript level and therefore may control gene expression during the life cycle of S. mansoni.

  2. Germline transgenesis and insertional mutagenesis in Schistosoma mansoni mediated by murine leukemia virus.

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    Gabriel Rinaldi

    Full Text Available Functional studies will facilitate characterization of role and essentiality of newly available genome sequences of the human schistosomes, Schistosoma mansoni, S. japonicum and S. haematobium. To develop transgenesis as a functional approach for these pathogens, we previously demonstrated that pseudotyped murine leukemia virus (MLV can transduce schistosomes leading to chromosomal integration of reporter transgenes and short hairpin RNA cassettes. Here we investigated vertical transmission of transgenes through the developmental cycle of S. mansoni after introducing transgenes into eggs. Although MLV infection of schistosome eggs from mouse livers was efficient in terms of snail infectivity, >10-fold higher transgene copy numbers were detected in cercariae derived from in vitro laid eggs (IVLE. After infecting snails with miracidia from eggs transduced by MLV, sequencing of genomic DNA from cercariae released from the snails also revealed the presence of transgenes, demonstrating that transgenes had been transmitted through the asexual developmental cycle, and thereby confirming germline transgenesis. High-throughput sequencing of genomic DNA from schistosome populations exposed to MLV mapped widespread and random insertion of transgenes throughout the genome, along each of the autosomes and sex chromosomes, validating the utility of this approach for insertional mutagenesis. In addition, the germline-transmitted transgene encoding neomycin phosphotransferase rescued cultured schistosomules from toxicity of the antibiotic G418, and PCR analysis of eggs resulting from sexual reproduction of the transgenic worms in mice confirmed that retroviral transgenes were transmitted to the next (F1 generation. These findings provide the first description of wide-scale, random insertional mutagenesis of chromosomes and of germline transmission of a transgene in schistosomes. Transgenic lines of schistosomes expressing antibiotic resistance could advance

  3. Binding of von Willebrand factor and plasma proteins to the eggshell of Schistosoma mansoni

    NARCIS (Netherlands)

    Dewalick, Saskia; Hensbergen, Paul J; Bexkens, Michiel L; Grosserichter-Wagener, Christina; Hokke, Cornelis H; Deelder, André M; de Groot, Philip G; Tielens, Aloysius G M; van Hellemond, Jaap J

    2014-01-01

    Schistosoma mansoni eggs have to cross the endothelium and intestinal wall to leave the host and continue the life cycle. Mechanisms involved in this essential step are largely unknown. Here we describe direct binding to the S. mansoni eggshell of von Willebrand factor and other plasma proteins invo

  4. 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...... infection and disease using urine samples from a large cohort from an area endemic for S. mansoni....

  5. A patologia da esquistossomose mansoni no coelho Pathology of Manson's shistosomiasis in rabits

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    Zilton A. Andrade

    1988-09-01

    liver had a focal distribution and therefore didi not appear to cause portal hypertension and had no resemblance to the human pathology seen in cases of hepatosplenic schistosomiasis. Pathology of schistosomiasis in rabbits has peculiar aspects, which are worthwhile studying, since the model can be interest for investigations, especially concerning the immunology and immunopathology of schistosomiasis mansoni.

  6. Cloning and Molecular Characterization of the Schistosoma mansoni Genes RbAp48 and Histone H4

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    Patrícia P Souza

    2002-10-01

    Full Text Available The human nuclear protein RbAp48 is a member of the tryptophan/aspartate (WD repeat family, which binds to the retinoblastoma (Rb protein. It also corresponds to the smallest subunit of the chromatin assembly factor and is able to bind to the helix 1 of histone H4, taking it to the DNA in replication. A cDNA homologous to the human gene RbAp48 was isolated from a Schistosoma mansoni adult worm library and named SmRbAp48. The full length sequence of SmRbAp48 cDNA is 1036 bp long, encoding a protein of 308 amino acids. The transcript of SmRbAp48 was detected in egg, cercariae and schistosomulum stages. The protein shows 84% similarity with the human RbAp48, possessing four WD repeats on its C-terminus. A hypothetical tridimensional structure for the SmRbAp48 C-terminal domain was constructed by computational molecular modeling using the b-subunit of the G protein as a model. To further verify a possible interaction between SmRbAp48 and S. mansoni histone H4, the histone H4 gene was amplified from adult worm genomic DNA using degenerated primers. The gene fragment of SmH4 is 294 bp long, encoding a protein of 98 amino acids which is 100% identical to histone H4 from Drosophila melanogaster.

  7. Impact of Schistosoma mansoni on malaria transmission in Sub-Saharan Africa.

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    Martial L Ndeffo Mbah

    2014-10-01

    Full Text Available Sub-Saharan Africa harbors the majority of the global burden of malaria and schistosomiasis infections. The co-endemicity of these two tropical diseases has prompted investigation into the mechanisms of coinfection, particularly the competing immunological responses associated with each disease. Epidemiological studies have shown that infection with Schistosoma mansoni is associated with a greater malaria incidence among school-age children.We developed a co-epidemic model of malaria and S. mansoni transmission dynamics which takes into account key epidemiological interaction between the two diseases in terms of elevated malaria incidence among individuals with S. mansoni high egg output. The model was parameterized for S. mansoni high-risk endemic communities, using epidemiological and clinical data of the interaction between S. mansoni and malaria among children in sub-Saharan Africa. We evaluated the potential impact of the S. mansoni-malaria interaction and mass treatment of schistosomiasis on malaria prevalence in co-endemic communities.Our results suggest that in the absence of mass drug administration of praziquantel, the interaction between S. mansoni and malaria may reduce the effectiveness of malaria treatment for curtailing malaria transmission, in S. mansoni high-risk endemic communities. However, when malaria treatment is used in combination with praziquantel, mass praziquantel administration may increase the effectiveness of malaria control intervention strategy for reducing malaria prevalence in malaria- S. mansoni co-endemic communities.Schistosomiasis treatment and control programmes in regions where S. mansoni and malaria are highly prevalent may have indirect benefits on reducing malaria transmission as a result of disease interactions. In particular, mass praziquantel administration may not only have the direct benefit of reducing schistosomiasis infection, it may also reduce malaria transmission and disease burden.

  8. In vitro and in vivo activities of arachidonic acid against Schistosoma mansoni and Schistosoma haematobium.

    Science.gov (United States)

    El Ridi, Rashika; Aboueldahab, Marwa; Tallima, Hatem; Salah, Mohamed; Mahana, Noha; Fawzi, Samia; Mohamed, Shadia H; Fahmy, Omar M

    2010-08-01

    The development of arachidonic acid (ARA) for treatment of schistosomiasis is an entirely novel approach based on a breakthrough discovery in schistosome biology revealing that activation of parasite tegument-bound neutral sphingomyelinase (nSMase) by unsaturated fatty acids, such as ARA, induces exposure of parasite surface membrane antigens to antibody binding and eventual attrition of developing schistosomula and adult worms. Here, we demonstrate that 5 mM ARA leads to irreversible killing of ex vivo 1-, 3-, 4-, 5-, and 6-week-old Schistosoma mansoni and 9-, 10-, and 12-week-old Schistosoma haematobium worms within 3 to 4 h, depending on the parasite age, even when the worms were maintained in up to 50% fetal calf serum. ARA-mediated worm attrition was prevented by nSMase inhibitors, such as CaCl(2) and GW4869. Scanning and transmission electron microscopy revealed that ARA-mediated worm killing was associated with spine destruction, membrane blebbing, and disorganization of the apical membrane structure. ARA-mediated S. mansoni and S. haematobium worm attrition was reproduced in vivo in a series of 6 independent experiments using BALB/c or C57BL/6 mice, indicating that ARA in a pure form (Sigma) or included in infant formula (Nestle) consistently led to 40 to 80% decrease in the total worm burden. Arachidonic acid is already marketed for human use in the United States and Canada for proper development of newborns and muscle growth of athletes; thus, ARA has potential as a safe and cost-effective addition to antischistosomal therapy. PMID:20479203

  9. The Schistosoma mansoni Cytochrome P450 (CYP3050A1 Is Essential for Worm Survival and Egg Development.

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    Peter D Ziniel

    2015-12-01

    Full Text Available Schistosomiasis affects millions of people in developing countries and is responsible for more than 200,000 deaths annually. Because of toxicity and limited spectrum of activity of alternatives, there is effectively only one drug, praziquantel, available for its treatment. Recent data suggest that drug resistance could soon be a problem. There is therefore the need to identify new drug targets and develop drugs for the treatment of schistosomiasis. Analysis of the Schistosoma mansoni genome sequence for proteins involved in detoxification processes found that it encodes a single cytochrome P450 (CYP450 gene. Here we report that the 1452 bp open reading frame has a characteristic heme-binding region in its catalytic domain with a conserved heme ligating cysteine, a hydrophobic leader sequence present as the membrane interacting region, and overall structural conservation. The highest sequence identity to human CYP450s is 22%. Double stranded RNA (dsRNA silencing of S. mansoni (SmCYP450 in schistosomula results in worm death. Treating larval or adult worms with antifungal azole CYP450 inhibitors results in worm death at low micromolar concentrations. In addition, combinations of SmCYP450-specific dsRNA and miconazole show additive schistosomicidal effects supporting the hypothesis that SmCYP450 is the target of miconazole. Treatment of developing S. mansoni eggs with miconazole results in a dose dependent arrest in embryonic development. Our results indicate that SmCYP450 is essential for worm survival and egg development and validates it as a novel drug target. Preliminary structure-activity relationship suggests that the 1-(2,4-dichlorophenyl-2-(1H-imidazol-1-ylethan-1-ol moiety of miconazole is necessary for activity and that miconazole activity and selectivity could be improved by rational drug design.

  10. Magnetic resonance imaging of cerebellar Schistosomiasis mansoni; Ressonancia magnetica na esquistossomose mansoni cerebelar

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Bruno Perocco; Costa Junior, Leodante Batista da [Hospital da Baleia, Belo Horizonte, MG (BRazil). Servico de Neurocirurgia; Lambertucci, Jose Roberto [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina. Servico de Doencas Infecciosas e Parasitarias

    2003-10-01

    A 15-year-old boy was admitted to hospital with a history of headache, dizziness, vomiting and double vision that started two weeks before. His parents denied any previous disease. During clinical examination he presented diplopia on lateral gaze to the left and horizontal nystagmus. No major neurological dysfunction was detected. He was well built, mentally responsive and perceptive. Laboratory findings revealed a leukocyte count of 10,000/mL, a normal red blood cell count and no eosinophilia. The magnetic resonance images (MRI) of the brain showed a left cerebellar lesion with mass effect compressing the surrounding tissues. Contrast-enhanced images showed a mass like structure and punctate nodules (Figures A and B: axial and coronal contrast-enhanced T1-weighted MR images showed the nodular - yellow arrows - enhancement pattern of a left cerebellar intraxial lesion). The lesion extended to the vermis and brachium pons and compressed the medulla. There was no hydrocephalus. He was taken to the operating room with the presumptive diagnosis of a neuroglial tumor, and submitted to a lateral suboccipital craniectomy. A brown, brittle tumoral mass without a clearly defined margin with the cerebellar tissue was removed. Microscopic examination revealed schistosomal granulomas in the productive phase in the cerebellum (Figure C). After surgery, treatment with praziquantel (50 mg/kg/dia, single dose) and prednisone (1 mg/kg/day) was offered and the patient improved quickly. Thirty days later he was seen again at the outpatient clinic: he was asymptomatic and with no neurological impairment. This is the eighth case of cerebellar involvement in schistosomiasis mansoni and the second report of a tumoral form of cerebellar schistosomiasis documented by magnetic resonance images. (author)

  11. Compounds Derived from the Bhutanese Daisy, Ajania nubigena, Demonstrate Dual Anthelmintic Activity against Schistosoma mansoni and Trichuris muris

    Science.gov (United States)

    Pearson, Mark S.; Giacomin, Paul R.; Becker, Luke; Sotillo, Javier; Pickering, Darren

    2016-01-01

    Background Whipworms and blood flukes combined infect almost one billion people in developing countries. Only a handful of anthelmintic drugs are currently available to treat these infections effectively; there is therefore an urgent need for new generations of anthelmintic compounds. Medicinal plants have presented as a viable source of new parasiticides. Ajania nubigena, the Bhutanese daisy, has been used in Bhutanese traditional medicine for treating various diseases and our previous studies revealed that small molecules from this plant have antimalarial properties. Encouraged by these findings, we screened four major compounds isolated from A. nubigena for their anthelmintic properties. Methodology/Principal Findings Here we studied four major compounds derived from A. nubigena for their anthelmintic properties against the nematode whipworm Trichuris muris and the platyhelminth blood fluke Schistosoma mansoni using the xWORM assay technique. Of four compounds tested, two compounds—luteolin (3) and (3R,6R)-linalool oxide acetate (1)—showed dual anthelmintic activity against S. mansoni (IC50 range = 5.8–36.9 μg/mL) and T. muris (IC50 range = 9.7–20.4 μg/mL). Using scanning electron microscopy, we determined luteolin as the most efficacious compound against both parasites and additionally was found effective against the schistosomula, the infective stage of S. mansoni (IC50 = 13.3 μg/mL). Luteolin induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. Our in vivo assessment of luteolin (3) against T. muris infection at a single oral dosing of 100 mg/kg, despite being significantly (27.6%) better than the untreated control group, was markedly weaker than mebendazole (93.1%) in reducing the worm burden in mice. Conclusions/Significance Among the four compounds tested, luteolin demonstrated the best broad-spectrum activity against two different helminths—T. muris and S. mansoni—and was

  12. Association of oxamniquine praziquantel and clonazepam in experimental Schistosomiasis mansoni

    OpenAIRE

    Neusa Araujo; Ana Carolina Alves Mattos; Paulo Marcos Zech Coelho; Naftale Katz

    2008-01-01

    The antischistosomal activity of clonazepam, when administered alone or in association with oxamniquine and praziquantel, was experimentally evaluated in mice infected with Schistosoma mansoni. The animals were treated 45 days post-infection with a single dose, by oral route, according to three treatment schedules: clonazepam 25 mg/kg and sacrificed 15 min, 1h or 4 h after treatment; clonazepam 1.0, 2.5 or 10.0 mg/kg and sacrificed 15 days post-treatment or with the dose of 10 mg/kg in associ...

  13. Bioactivity of miltefosine against aquatic stages of Schistosoma mansoni, Schistosoma haematobium and their snail hosts, supported by scanning electron microscopy

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    El Bardicy Samia

    2011-05-01

    Full Text Available Abstract Background Miltefosine, which is the first oral drug licensed for the treatment of leishmaniasis, was recently reported to be a promising lead compound for the synthesis of novel antischistosomal derivatives with potent activity in vivo against different developmental stages of Schistosoma mansoni. In this paper an in vitro study was carried out to investigate whether it has a biocidal activity against the aquatic stages of Schistosoma mansoni and its snail intermediate host, Biomphalaria alexandrina , thus being also a molluscicide. Additionally, to see whether miltefosine can have a broad spectrum antischistosomal activity, a similar in vitro study was carried out on the adult stage of Schistosoma haematobium, the second major human species, its larval stages and snail intermediate host, Bulinus truncutes. This was checked by scanning electron microscopy. Results Miltefosine proved to have in vitro ovicidal, schistolarvicidal and lethal activity on adult worms of both Schistosoma species and has considerable molluscicidal activity on their snail hosts. Scanning electron microscopy revealed several morphological changes on the different stages of the parasite and on the soft body of the snail, which further strengthens the current evidence of miltefosine's activity. This is the first report of mollusicidal activity of miltefosine and its in vitro schistosomicidal activity against S.haematobium. Conclusions This study highlights miltefosine not only as a potential promising lead compound for the synthesis of novel broad spectrum schistosomicidal derivatives, but also for molluscicidals.

  14. Importância epidemiológica de alguns animais silvestres na esquistossomose mansônica Epidemiologic importance of some wild rodents in the schistosomiasis mansoni

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    Urara Kawazoe

    1983-10-01

    ência da contaminação humana, na natureza. Porém, é possível que, futuramente, H. b. leucogaster na presença de B. glabrata, possa servir de reservatório da esquistossomose, na natureza, quando encontrados em abundância e desde que adaptados com cepas adequadas do parasita.The importance of some wild rodents as possible reservoir hosts of S. mansoni related to the epidemiologic chain of this parasite and some biological aspects of these rodents were studied in semi-natural habitats. The experiment was performed in an enclosed area of about 1,000 m² situated in Taubaté, State of S. Paulo, one of the endemic area of human schistosomiasis, during a period of three years and six months (from August 1973 to December 1976. Wild rodents of the following species were used as definitive hosts: Holochilus brasiliensis leucogaster, Zygodontomys lasiurus, Oryzomys nigripes eliurus and Cavia aperea aperea. Biomphalaria tenagophila and B. glabrata were used as intermediate hosts. From August 1973 to January 1976 it was not possible to find any B. tenagophila eliminating S. mansoni cercariae nor any rodents infected with the same parasite. In August, 1975, egg patches of B. glabrata snails were accidentaly introduced into the area and in 1976 some adult snails were eliminating S. mansoni cercariae. In that same year, two Holochilus that were born in the area were discharging S. mansoni eggs in their feces. Some biological data were collected from 41 H. b. leucogaster of which 28 individuals were introduced into and 14 were born in the area. The majority of body weights of rodents born in the area and captured for the first time was between 20 and 50 grams. In this group of 41 rodents observed, body weight continued to increase throughout the life span of each individual sampled. Z. lasiurus and C. a. aperea did not show any infection with S. mansoni and they did not leave any progeny in the area. O. n. eliurus reproduced in the area and remaining there for about 100 days did

  15. Schistosoma mansoni and Host-Parasite Interactions

    NARCIS (Netherlands)

    S.M-C.A. de Walick (Saskia)

    2015-01-01

    markdownabstract__Abstract__ Blood-dwelling parasitic trematodes (flatworms) of the genus Schistosoma cause the disease schistosomiasis or Bilharzia. There are 5 different Schistosoma species that infect humans and many other infecting different mammals. Over 200 million people worldwide are infect

  16. Conservation and developmental expression of ubiquitin isopeptidases in Schistosoma mansoni

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    Roberta Verciano Pereira

    2014-02-01

    Full Text Available Several genes related to the ubiquitin (Ub-proteasome pathway, including those coding for proteasome subunits and conjugation enzymes, are differentially expressed during the Schistosoma mansoni life cycle. Although deubiquitinating enzymes have been reported to be negative regulators of protein ubiquitination and shown to play an important role in Ub-dependent processes, little is known about their role in S. mansoni . In this study, we analysed the Ub carboxyl-terminal hydrolase (UCHs proteins found in the database of the parasite’s genome. An in silico ana- lysis (GeneDB and MEROPS identified three different UCH family members in the genome, Sm UCH-L3, Sm UCH-L5 and Sm BAP-1 and a phylogenetic analysis confirmed the evolutionary conservation of the proteins. We performed quantitative reverse transcription-polymerase chain reaction and observed a differential expression profile for all of the investigated transcripts between the cercariae and adult worm stages. These results were corroborated by low rates of Z-Arg-Leu-Arg-Gly-Gly-AMC hydrolysis in a crude extract obtained from cercariae in parallel with high Ub conjugate levels in the same extracts. We suggest that the accumulation of ubiquitinated proteins in the cercaria and early schistosomulum stages is related to a decrease in 26S proteasome activity. Taken together, our data suggest that UCH family members contribute to regulating the activity of the Ub-proteasome system during the life cycle of this parasite.

  17. Compatibility of Schistosoma mansoni Cameroon and Biomphalaria pfeifferi Senegal.

    Science.gov (United States)

    Southgate, V R; Tchuenté, L A; Théron, A; Jourdane, J; Ly, A; Moncrieff, C B; Gryseels, B

    2000-11-01

    The vectorial capacity of Biomphalaria pfeifferi from Ndiangue, Senegal, was investigated with an allopatric isolate of Schistosoma mansoni from Nkolbisson, Cameroon. The snail infection rate after exposure to a single miracidium per snail (MD1) was 56. 3 %, and 91.6%, for snails exposed to 5 miracidia per snail (MD5). The minimum pre-patent period was 21 days. The mean total cercarial production for the MDI group was 18,511 cercariae per snail, and 9757 cercariae for the MD5 group. The maximum production of cercariae for 1 day was 4892 observed in a snail from the MDI group at day 43 post-infection. The mean longevity of snails was higher in group MD1 (88 days p.i.) than in group MD5 (65 days p.i.). The chronobiological emergence pattern revealed a circadian rhythm with one shedding peak at mid-day. Comparisons are made with the vectorial capacity of the sympatric combination of B. pfeifferi Senegal/S. mansoni Senegal.

  18. 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.

  19. Two Isoforms of a Divalent Metal Transporter (DMT1) in Schistosoma mansoni Suggest a Surface-associated Pathway for Iron Absorption in Schistosomes*

    OpenAIRE

    Smyth, Danielle J.; Glanfield, Amber; McManus, Donald P; Hacker, Elke; Blair, David; Anderson, Greg J.; Jones, Malcolm K.

    2005-01-01

    We describe two homologues of the mammalian divalent metal transporter (DMT1) for Schistosoma mansoni, a pathogenic intravascular parasite of humans. Schistosomes have a high nutritional and metabolic demand for iron. Nucleotide sequences of the parasite homologues, designated SmDMT1A and -B, are identical in all but the 5′-regions. The predicted amino acid sequences share at least 60% identity with DMT1 (=Nramp2) of humans, mice, and rats, and at least 55% identity with Nramp1 from mice, hum...

  20. An Isochore-Like Structure in the Genome of the Flatworm Schistosoma mansoni.

    Science.gov (United States)

    Lamolle, Guillermo; Protasio, Anna V; Iriarte, Andrés; Jara, Eugenio; Simón, Diego; Musto, Héctor

    2016-01-01

    Eukaryotic genomes are compositionally heterogeneous, that is, composed by regions that differ in guanine-cytosine (GC) content (isochores). The most well documented case is that of vertebrates (mainly mammals) although it has been also noted among unicellular eukaryotes and invertebrates. In the human genome, regarded as a typical mammal, this heterogeneity is associated with several features. Specifically, genes located in GC-richest regions are the GC3-richest, display CpG islands and have shorter introns. Furthermore, these genes are more heavily expressed and tend to be located at the extremes of the chromosomes. Although the compositional heterogeneity seems to be widespread among eukaryotes, the associated properties noted in the human genome and other mammals have not been investigated in depth in other taxa Here we provide evidence that the genome of the parasitic flatworm Schistosoma mansoni is compositionally heterogeneous and exhibits an isochore-like structure, displaying some features associated, until now, only with the human and other vertebrate genomes, with the exception of gene concentration. PMID:27435793

  1. Schistosoma mansoni antigens alter the cytokine response in vitro during cutaneous leishmaniasis

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    Aline Michelle Barbosa Bafica

    2011-11-01

    Full Text Available Schistosoma mansoni infection or associated products are able to down-modulate the type 1 CD4+ T cell inflammatory response characteristic of autoimmune diseases. In this study, we evaluated how S. mansoni antigens altered the immune response that was induced by the soluble Leishmania antigen (SLA from cutaneous leishmaniasis (CL patients. Cytokines were measured from the supernatants of peripheral blood mononuclear cell cultures stimulated with SLA. This was performed using the sandwich enzyme linked immunosorbent assay technique in the presence or absence of S. mansoni recombinant antigens Sm29, SmTSP-2 and PIII. The addition of S. mansoni antigens to the cultures resulted in the reduction of interferon gamma (IFN-γ levels in 37-50% of patients. Although to a lesser extent, the antigens were also able to decrease the production of tumour necrosis factor-alpha (TNF-α. We compared patients that either had or did not have reduction in IFN-γ and TNF-α production in cultures stimulated with SLA in the presence of S. mansoni antigens. We found that there was no significant difference in the levels of interleukin (IL-10 and IL-5 in response to S. mansoni antigens between the groups. The antigens used in this study down-modulated the in vitro proinflammatory response induced by SLA in a group of CL patients through a currently undefined mechanism.

  2. Mechanisms of evasion of Schistosoma mansoni schistosomula to the lethal activity of complement

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    F. Juarez Ramalho-Pinto

    1992-01-01

    Full Text Available Schistosomula of Schistosoma mansoni became resistant to antibody-dependent complement damage in vitro after pre-incubation with normal human erythrocytes (NHuE whatever the ABO or Rh blood group. Resistant parasites were shown to acquire host decay accelerating factor (DAF , a 70 kDa glycoprotein attached to the membrane of NHue by a GPI anchor. IgG2a mAb anti-human DAF (IA10 immunoprecipitated a 70 kDa molecule from 125I-labeled schistosomula pre-incubated with NHuE and inhibited their resistance to complement-dependent killing in vtro. Incubationof schistosomula with erytrocytes from patients with paroxsimal nocturnal hemoglobinuria (PNHE or SRBC, wich are DAF-deficient, did not protect the parasites from complement lesion. Supernatant of 100,000 x g collected from NHuE incubated for 24 h in defined medium was shown to contain a soluble form of DAF and to protect schistosomula from complement killing. Schistosomula treated with trypsin before incubation with NHuE ghosts did not become resistant to complement damage. On the other hand, pre-treatment with chymotrypsin did not interfere with the acquisition of resistance by the schistosomula. These results indicate that, in vitro, NHuE DAF can be transferred to schistosomula in a soluble form and that the binding of this molecule to the parasite surface is dependent upon trypsin-sensitive chymotrypsin-insensitive polipeptide(s present on the surface of the worm.

  3. Acute schistosomiasis mansoni: revisited and reconsidered

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    José Roberto Lambertucci

    2010-07-01

    Full Text Available Acute schistosomiasis is a systemic hypersensitivity reaction against the migrating schistosomula and eggs. A variety of clinical manifestations appear during the migration of schistosomes in humans: cercarial dermatitis, fever, pneumonia, diarrhoea, hepatomegaly, splenomegaly, skin lesions, liver abscesses, brain tumours and myeloradiculopathy. Hypereosinophilia is common and aids diagnosis. The disease has been overlooked, misdiagnosed, underestimated and underreported in endemic areas, but risk groups are well known, including military recruits, some religious congregations, rural tourists and people practicing recreational water sports. Serology may help in diagnosis, but the finding of necrotic-exudative granulomata in a liver biopsy specimen is pathognomonic. Differentials include malaria, tuberculosis, typhoid fever, kala-azar, prolonged Salmonella bacteraemia, lymphoma, toxocariasis, liver abscesses and fever of undetermined origin. For symptomatic hospitalised patients, treatment with steroids and schistosomicides is recommended. Treatment is curative in those timely diagnosed.

  4. Immunization against Egyptian Schistosoma mansoni infection by multivalent DNA vaccine

    Institute of Scientific and Technical Information of China (English)

    Mahmoud H Romeih; Hanem M Hassan; Tarek S Abou Shousha; Mohamed A Saber

    2008-01-01

    The development of multivalent vaccines consisting of several antigens is a novel approach to creating broad-range protection against different parasite strains and parasite life cycle stages. We have previously confirmed that the schistosome Sm21.7 and SmFimbrin (SmFim) proteins could induce protection in mice. Therefore, this study aimed to construct the multivalent DNA vaccine Sm21.7-SmFim/pBudCE4.1 and evaluate its immune efficacy. The open reading frames of two Schistosoma mansoni genes, Sm21.7 and SmFim, were inserted into the eukaryotic expression plasmid pBudCE4.1 designed for the independent expression of two genes in mammalian cells. To evaluate the in vitro expression of the multivalent Sm21.7-SmFim/pBudCE4.1 DNA vaccine and its immunological effect in mice, the recombinant plasmid Sm21.7-SmFim/pBudCE4.1 was used to transfect 293T cells, and the expression of mRNA and proteins was examined using reverse transcription-polymerase chain reaction and Western blot analysis. Then the ability of Sm21.7.SmFim/pBudCE4.1 to protect against S. mansoni challenge infections was analyzed according to worm burden and egg reduction rates after vaccination of mice. Vaccinated mice showed a significant level of protection (56%), and a decrease in the number and size, and change in the cellular profile, of granulomas. Egg reduction in liver and intestine was 41.53% and 55.63%,respectively, as determined relative to mice that received the empty vector only. In addition to reductions in worm viability,worm fecundity and egg hatching ability were observed following challenge infection in the immunized group.Results showed that Sm21.7-SmFim/pBudCE4.1 could express Sm 21.7 and SmFim mRN A and proteins. Enzyme-linked immunosorbent assay and Western blot analysis indicated that immunized mice generated specific immunoglobulin G against Sm21.7-SmFim/pBudCE4.1. These results suggest that vaccination with multivalent S. mansoni DNA vaccine (SmFim-Sm21.7/pBudCE4.1) not only induces a

  5. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

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    Omar dos Santos Carvalho

    1976-10-01

    ções ditas semi-naturais. Os primeiros estudos, entretanto, de Antunes, Milward de Andrade, Katz & Coelho4,,em 1971 e de Antunes5, em 1971 foram feitos utilizando-se o Nectomys s. squamipes.Close to the Pampulha Lake, Belo Horizonte, MG (Brazil, there were collected (july/72 -November/73 28 specimens of Holochilus brasiliensis, 11 of them (39.3% eliminating S. mansoni viable eggs in their faeces. Miracidia from the strain above ("H" could infected Biomphalaria glabrata, the cercariae shed later being also able to infect albino mice, from whose faeces 35,3% of adult worms were recovered in the end of the experiment. S. mansoni cercariae from human strain ("LE" infected 7 H. brasiliensis laboratory specimens, and 30,5% of adult worms could be recovered in the end of 60 days. Anatomopathological studies of H. brasiliensis demonstrated generalized infection, granulomes being detected in the esophagus, stomach, intestines (small and large, tiver, spleen, pancreas and abdominal lymphnodes. Fibrous thickenning of the portal vein intima, granulomes in portal spaces an incipient fibrosis of portal and interlobular spaces were the lesion triggered by the presence of S. mansoni eggs in the liver. In semi-natural surroundings (Fig. 1, the life cycle of S. mansoni could be completed, with no human interference, by using B. glabrata experimentally infected with trematodes from "LE" strain, laboratory-bred H. brasiliensis and B. glabrata specimens from hat seminatural surroundings. It was observed that both strains ("H" and "LE" displayed similar behaviour, no morphological differences having been detected between their eggs and adult worms. Field and laboratory studies demonstrated Holochilus brasiliensis to be a satisfactory intermediate host of S. mansoni. It is than possible that, under certains ecological conditions, the cricetids under study may eventually be integrated in the trematode natural cycle, independently from or parallely the presence of man. It must finally be pointed out

  6. The effect of Zymomonas mobilis culture on experimental Schistosoma mansoni infection O efeito da cultura de Zymomonas mobilis na infecção experimental por Schistosoma mansoni

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    Juliana de Fátima Macedo Santos

    2004-12-01

    Full Text Available C57Bl/10 male mice infected with Schistosoma mansoni were distributed into mixed, prophylactic and curative groups. A culture of Zymomonas mobilis was orally administered to mice. A 61% protection from the infection was observed in the curative group (p Camundongos C57Bl/10 do sexo masculino, infectados com Schistosoma mansoni foram distribuídos nos grupos misto, profilático e curativo. Cultura de Zymomonas mobilis foi administrada oralmente aos camundongos. Uma proteção de 61% foi observada no grupo curativo (p<0,05. Os estudos histopatológicos dos fígados e intestinos mostraram resultados similares.

  7. [Schistosoma mansoni in the context of the Brazilian health policy].

    Science.gov (United States)

    Tibiriçá, Sandra Helena Cerrato; Guimarães, Frederico Baêta; Teixeira, Maria Teresa Bustamente

    2011-01-01

    There are many factors involved in the determination of the emergence and reemergence of infectious diseases. In the case of Schistosomiasis biological factors are highlighted as related to the habitat, to the microorganisms and hosts adaptations and mutations, to the immunologic reply of the host and to the bio-ecology adaptations of intermediate hosts. These are added to the not less important factors related to the management politics, occupation of the environment and allocation of financial resources. Brazil congregates, today, an important echo-epidemiologic conditions for the reemergence of Schistosomiasis. The expansion of its borders reaches the urban and agricultural environments, destined to work or leisure, also damaging income sectors as the ecotourism. The advances in the researches concerning the intermediate and definitive hosts of the Schistosoma mansoni, to change them into public benefits, need the public sustainability, compromised, interdisciplinary, and strengthened in the government's different spheres. The organized civil society has fundamental paper in the control of the government actions.

  8. Hypertensive portal colopathy in schistosomiasis mansoni: proposal for a classification

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    Maria Angelina C Miranda

    2004-08-01

    Full Text Available Portal hypertension is a frequent complication of chronic liver disease, detected not only in schistosomiasis, but also in cirrhosis of any etiology. Vascular alterations in the colonic mucosa are a potential source for acute or chronic bleeding and have been observed in patients with portal hypertension. The purpose of this prospective study was to describe and propose a classification for the vascular alterations of portal hypertension in the colonic mucosa among patients with hepatosplenic schistosomiasis mansoni. One or more alterations of portal colopathy were observed in all patients and they were classified according to their intensity, obeying the classification proposed by the authors. Portal colopathy is an important finding in hepatosplenic schistosomiasis and might be the cause of lower gastrointestinal bleeding in patients with severe portal hypertension.

  9. Splenectomy Improves Hemostatic and Liver Functions in Hepatosplenic Schistosomiasis Mansoni.

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    Luiz Arthur Calheiros Leite

    Full Text Available Schistosomiasis mansoni is a chronic liver disease, in which some patients (5-10% progress to the most severe form, hepatosplenic schistosomiasis. This form is associated with portal hypertension and splenomegaly, and often episodes of gastrointestinal bleeding, even with liver function preserved. Splenectomy is a validated procedure to reduce portal hypertension following digestive bleeding. Here, we evaluate beneficial effects of splenectomy on blood coagulation factors and liver function tests in hepatosplenic schistosomiasis mansoni compared to non-operated patients.Forty-five patients who had undergone splenectomy surgery were assessed by laboratory analyses and ultrasound examination and compared to a non-operated group (n = 55. Blood samples were obtained for liver function tests, platelet count and prothrombin time. Coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa, plasminogen activator inhibitor-1 were measured by routine photometric, chromogenic or enzyme-linked immunosorbent assays, while hyperfibrinolysis was defined by plasminogen activator inhibitor-1 levels. Both groups had similar age, gender and pattern of periportal fibrosis. Splenectomized patients showed significant reductions in portal vein diameter, alkaline phosphatase and bilirubin levels compared to non-operated patients, while for coagulation factors there were significant improvement in prothrombin, partial thromboplastin times and higher levels of factor VII, VIII, IX, X, protein C and plasminogen activator inhibitor-1.This study shows that the decrease of flow pressure in portal circulation after splenectomy restores the capacity of hepatocyte synthesis, especially on the factor VII and protein C levels, and these findings suggest that portal hypertension in patients with hepatosplenic schistosomiasis influences liver functioning and the blood coagulation status.

  10. Association of oxamniquine praziquantel and clonazepam in experimental Schistosomiasis mansoni

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    Neusa Araujo

    2008-12-01

    Full Text Available The antischistosomal activity of clonazepam, when administered alone or in association with oxamniquine and praziquantel, was experimentally evaluated in mice infected with Schistosoma mansoni. The animals were treated 45 days post-infection with a single dose, by oral route, according to three treatment schedules: clonazepam 25 mg/kg and sacrificed 15 min, 1h or 4 h after treatment; clonazepam 1.0, 2.5 or 10.0 mg/kg and sacrificed 15 days post-treatment or with the dose of 10 mg/kg in association with oxamniquine 50 mg/kg or praziquantel 200 mg/kg, single dose, orally, every schedule with a control group. The efficacy of the drugs in vivo was assessed by means of worm counts and their distribution in mesentery and liver, mortality and oogram changes. In the chemotherapeutic schedules used, clonazepam did not present antischistosomal activity and the result of the association of this drug with oxamniquine or praziquantel was not significantly different from the one obtained when these two last drugs were administered alone. In the in vitro experiments, the worms exposed to 0.6 mg/mL clonazepam remained motionless throughout the 8-day-period of observation, without egg-laying, whereas the worms of the control group showed normal movements, egg-laying and hatching of miracidia on the last day of observation. The results obtained in the present study confirm the action of clonazepam on S. mansoni adult worm, in vitro, causing total paralysis of males and females. However, no additive or synergistic effects were observed when clonazepam were used in association with oxamniquine or praziquantel.

  11. Influence of Schistosoma mansoni and Hookworm Infection Intensities on Anaemia in Ugandan Villages.

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    Goylette F Chami

    Full Text Available The association of anaemia with intestinal schistosomiasis and hookworm infections are poorly explored in populations that are not limited to children or pregnant women.We sampled 1,832 individuals aged 5-90 years from 30 communities in Mayuge District, Uganda. Demographic, village, and parasitological data were collected. Infection risk factors were compared in ordinal logistic regressions. Anaemia and infection intensities were analyzed in multilevel models, and population attributable fractions were estimated.Household and village-level predictors of Schistosoma mansoni and hookworm were opposite in direction or significant for single infections. S. mansoni was found primarily in children, whereas hookworm was prevalent amongst the elderly. Anaemia was more prevalent in individuals with S. mansoni and increased by 2.86 fold (p-value<0.001 with heavy S. mansoni infection intensity. Individuals with heavy hookworm were 1.65 times (p-value = 0.008 more likely to have anaemia than uninfected participants. Amongst individuals with heavy S. mansoni infection intensity, 32.0% (p-value<0.001 of anaemia could be attributed to S. mansoni. For people with heavy hookworm infections, 23.7% (p-value = 0.002 of anaemia could be attributed to hookworm. A greater fraction of anaemia (24.9%, p-value = 0.002 was attributable to heavy hookworm infections in adults (excluding pregnant women as opposed to heavy hookworm infections in school-aged children and pregnant women (20.2%, p-value = 0.001.Community-based surveys captured anaemia in children and adults affected by S. mansoni and hookworm infections. For areas endemic with schistosomiasis or hookworm infections, WHO guidelines should include adults for treatment in helminth control programmes.

  12. Vaccination with antioxidant enzymes confers protective immunity against challenge infection with Schistosoma mansoni

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    Philip T LoVerde

    2004-08-01

    Full Text Available Schistosoma mansoni, an intravascular parasite, lives in a hostile environment in close contact with host humoral and cellular cytotoxic factors. To establish itself in the host, the parasite has evolved a number of immune evasion mechanisms, such as antioxidant enzymes. Our laboratory has demonstrated that the expression of antioxidant enzymes is developmentally regulated, with the highest levels present in the adult worm, the stage least susceptible to immune elimination, and the lowest levels in the larval stages, the most susceptible to immune elimination. Vaccination of mice with naked DNA constructs containing Cu/Zn cytosolic superoxide dismutase (CT-SOD, signal-peptide containing SOD or glutathione peroxidase (GPX showed significant levels of protection compared to a control group. We have further shown that vaccination with SmCT-SOD but not SmGPX results in elimination of adult worms. Anti-oxidant enzyme vaccine candidates offer an advance over existing vaccine strategies that all seem to target the larval developmental stages in that they target adult worms and thus may have therapeutic as well as prophylactic value. To eliminate the potential for cross-reactivity of SmCT-SOD with human superoxide dismutase, we identified parasite-specific epitope-containing peptides. Our results serve as a basis for developing a subunit vaccine against schistosomiasis.

  13. Schistosoma mansoni: vaccination of mice with 10-krad-irradiated, cryopreserved schistosomules

    International Nuclear Information System (INIS)

    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

  14. A bacterial artificial chromosome library for Biomphalaria glabrata, intermediate snail host of Schistosoma mansoni

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    Coen M Adema

    2006-10-01

    Full Text Available To provide a novel resource for analysis of the genome of Biomphalaria glabrata, members of the international Biomphalaria glabrata Genome Initiative (biology.unm.edu/biomphalaria-genome.html, working with the Arizona Genomics Institute (AGI and supported by the National Human Genome Research Institute (NHGRI, produced a high quality bacterial artificial chromosome (BAC library. The BB02 strain B. glabrata, a field isolate (Belo Horizonte, Minas Gerais, Brasil that is susceptible to several strains of Schistosoma mansoni, was selfed for two generations to reduce haplotype diversity in the offspring. High molecular weight DNA was isolated from ovotestes of 40 snails, partially digested with HindIII, and ligated into pAGIBAC1 vector. The resulting B. glabrata BAC library (BG_BBa consists of 61824 clones (136.3 kb average insert size and provides 9.05 × coverage of the 931 Mb genome. Probing with single/low copy number genes from B. glabrata and fingerprinting of selected BAC clones indicated that the BAC library sufficiently represents the gene complement. BAC end sequence data (514 reads, 299860 nt indicated that the genome of B. glabrata contains ~ 63% AT, and disclosed several novel genes, transposable elements, and groups of high frequency sequence elements. This BG_BBa BAC library, available from AGI at cost to the research community, gains in relevance because BB02 strain B. glabrata is targeted whole genome sequencing by NHGRI.

  15. Changes on Schistosoma mansoni (Digenea: Schistosomatidae worm load in Nectomys squamipes (Rodentia: Sigmodontinae concurrently infected with Echinostoma paraensei (Digenea: Echinostomatidae

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    Arnaldo Maldonado Júnior

    2001-09-01

    Full Text Available The water rat, Nectomys squamipes, closely involved in schistosomiasis transmission in Brazil, has been found naturally infected simultaneously by Schistosoma mansoni and Echinostoma paraensei. Laboratory experiments were conducted to verify parasitic interaction in concurrent infection. It was replicated four times with a total of 42 water rats and essayed two times with 90 mice pre-infected with E. paraensei. Rodents were divided into three groups in each replication. A wild strain recently isolated from Sumidouro, RJ, and a laboratory strain of S. mansoni from Belo Horizonte (BH was used. Rats infected with E. paraensei were challenged 4 weeks later with S. mansoni and mice 2 or 6 weeks after the infection with S. mansoni. Necropsy took place 8 weeks following S. mansoni infection. The N. squamipes treatment groups challenged with S. mansoni RJ strain showed a significant decrease (80 and 65% in the S. mansoni parasite load when compared with their respective control groups. There was a significant change or no change in the hosts challenged with the BH strain. The persistence time of E. paraensei within host was extended in relation to control groups, with a consequent enhancement of the number of recovered worm. An E. paraensei strain-specific influence on S. mansoni parasitism is reported. This paper presents some experimental data about this interaction in N. squamipes and Mus musculus.

  16. Epigenetic modulation, stress and plasticity in susceptibility of the snail host, Biomphalaria glabrata, to Schistosoma mansoni infection.

    Science.gov (United States)

    Knight, Matty; Ittiprasert, Wannaporn; Arican-Goktas, Halime D; Bridger, Joanna M

    2016-06-01

    Blood flukes are the causative agent of schistosomiasis - a major neglected tropical disease that remains endemic in numerous countries of the tropics and sub-tropics. During the past decade, a concerted effort has been made to control the spread of schistosomiasis, using a drug intervention program aimed at curtailing transmission. These efforts notwithstanding, schistosomiasis has re-emerged in southern Europe, raising concerns that global warming could contribute to the spread of this disease to higher latitude countries where transmission presently does not take place. Vaccines against schistosomiasis are not currently available and reducing transmission by drug intervention programs alone does not prevent reinfection in treated populations. These challenges have spurred awareness that new interventions to control schistosomiasis are needed, especially since the World Health Organization hopes to eradicate the disease by 2025. For one of the major species of human schistosomes, Schistosoma mansoni, the causative agent of hepatointestinal schistosomiasis in Africa and the Western Hemisphere, freshwater snails of the genus Biomphalaria serve as the obligate intermediate host of this parasite. To determine mechanisms that underlie parasitism by S. mansoni of Biomphalaria glabrata, which might be manipulated to block the development of intramolluscan larval stages of the parasite, we focused effort on the impact of schistosome infection on the epigenome of the snail. Results to date reveal a complex relationship, manifested by the ability of the schistosome to manipulate the snail genome, including the expression of specific genes. Notably, the parasite subverts the stress response of the host to ensure productive parasitism. Indeed, in isolates of B. glabrata native to central and South America, susceptible to infection with S. mansoni, the heat shock protein 70 (Bg-HSP70) gene of this snail is rapidly relocated in the nucleus and transcribed to express HSP70

  17. The diterpenoid 7-keto-sempervirol, derived from Lycium chinense, displays anthelmintic activity against both Schistosoma mansoni and Fasciola hepatica.

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    Jennifer Edwards

    2015-03-01

    Full Text Available BACKGROUND: Two platyhelminths of biomedical and commercial significance are Schistosoma mansoni (blood fluke and Fasciola hepatica (liver fluke. These related trematodes are responsible for the chronic neglected tropical diseases schistosomiasis and fascioliasis, respectively. As no vaccine is currently available for anti-flukicidal immunoprophylaxis, current treatment is mediated by mono-chemical chemotherapy in the form of mass drug administration (MDA (praziquantel for schistosomiasis or drenching (triclabendazole for fascioliasis programmes. This overreliance on single chemotherapeutic classes has dramatically limited the number of novel chemical entities entering anthelmintic drug discovery pipelines, raising significant concerns for the future of sustainable blood and liver fluke control. METHODOLOGY/ PRINCIPLE FINDINGS: Here we demonstrate that 7-keto-sempervirol, a diterpenoid isolated from Lycium chinense, has dual anthelmintic activity against related S. mansoni and F. hepatica trematodes. Using a microtiter plate-based helminth fluorescent bioassay (HFB, this activity is specific (Therapeutic index = 4.2, when compared to HepG2 cell lines and moderately potent (LD50 = 19.1 μM against S. mansoni schistosomula cultured in vitro. This anti-schistosomula effect translates into activity against both adult male and female schistosomes cultured in vitro where 7-keto-sempervirol negatively affects motility/behaviour, surface architecture (inducing tegumental holes, tubercle swelling and spine loss/shortening, oviposition rates and egg morphology. As assessed by the HFB and microscopic phenotypic scoring matrices, 7-keto-sempervirol also effectively kills in vitro cultured F. hepatica newly excysted juveniles (NEJs, LD50 = 17.7 μM. Scanning electron microscopy (SEM evaluation of adult F. hepatica liver flukes co-cultured in vitro with 7-keto-sempervirol additionally demonstrates phenotypic abnormalities including breaches in tegumental

  18. Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on intensity of infection and antibody responses to schistosome antigens

    DEFF Research Database (Denmark)

    Tweyongyere, Robert; Mawa, Patrice A.; Emojong, Nicholas O.;

    2009-01-01

    Schistosoma mansoni during pregnancy, compared with treatment after delivery. Methods A nested cohort of 387 Schistosoma mansoni infected women was recruited within a larger trial of de-worming during pregnancy. Women were randomised to receive praziquantel or placebo during pregnancy. All women were treated...... after delivery. Infection intensity after treatment was assessed by a single Kato-Katz examination of stool samples with duplicate slides and categorised as undetected, light (1-99 eggs per gram (epg)), moderate (100-399 epg) or heavy (=400 epg). Antibodies against S. mansoni worm and egg antigens were...... infection (median (IQR) epg: 749 (521, 1169)) with S. mansoni. At six weeks after praziquantel treatment during pregnancy S. mansoni infection was not detectable in 81.9% of the women and prevalence and intensity had decreased to 11.8% light, 4.7% moderate and 1.6% heavy a similar reduction when compared...

  19. Therapy with bone marrow cells reduces liver alterations in mice chronically infected by Schistosoma mansoni

    Institute of Scientific and Technical Information of China (English)

    Sheilla Andrade Oliveira; Bruno Solano Freitas Souza; Cada Adriana Guimar(a)es-Ferreira; Elton Sá Barreto; Siane Campos Souza; Luiz Antonio Rodrigues Freitas; Ricardo Ribeiro-dos-Santos; Milena Botelho Pereira Soares

    2008-01-01

    AIM: To investigate the potential of bone marrow mononuclear cells (BM-MCs) in the regeneration of hepatic lesions induced by Schistosoma mansoni (S.mansoni) chronic infection.METHODS: Female mice chronically infected with S.mansoni were treated with BM-MCs obtained from male green fluorescent protein (GFP) transgenic mice by intravenous or intralobular injections. Control mice received injections of saline in similar conditions. Enzyme-linked immunosorbent assay (ELISA) assay for transforming growth factor-beta (TGF-β), polymerase chain reaction (PCR) for GFP DNA, immunofluorescence and morphometric studies were performed.RESULTS: Transplanted GFP+ cells migrated to granuloma areas and reduced the percentage of liver fibrosis. The presence of donor-derived cells was confirmed by Fluorescence in situ hybridization (FISH) analysis for detection of cells bearing Y chromosome and by PCR analysis for detection of GFP DNA. The levels of TGF-β, a cytokine associated with fibrosis deposition, in liver fragments of mice submitted to therapy were reduced. The number of oval cells in liver sections of S.rnansoni-infected mice increased 3-4 fold after transplantation. A partial recovery in albumin expression, which is decreased upon infection with S.mansoni, was found in livers of infected mice after cellular therapy.CONCLUSION: In conclusion, transplanted BMCs migrate to and reduce the damage of chronic fibrotic liver lesions caused by S.mansoni.

  20. Novel Non-Peptide Inhibitors against SmCL1 of Schistosoma mansoni: In Silico Elucidation, Implications and Evaluation via Knowledge Based Drug Discovery.

    Science.gov (United States)

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

    2015-01-01

    Schistosomiasis is a major endemic disease known for excessive mortality and morbidity in developing countries. Because praziquantel is the only drug available for its treatment, the risk of drug resistance emphasizes the need to discover new drugs for this disease. Cathepsin SmCL1 is the critical target for drug design due to its essential role in the digestion of host proteins for growth and development of Schistosoma mansoni. Inhibiting the function of SmCL1 could control the wide spread of infections caused by S. mansoni in humans. With this objective, a homology modeling approach was used to obtain theoretical three-dimensional (3D) structure of SmCL1. In order to find the potential inhibitors of SmCL1, a plethora of in silico techniques were employed to screen non-peptide inhibitors against SmCL1 via structure-based drug discovery protocol. Receiver operating characteristic (ROC) curve analysis and molecular dynamics (MD) simulation were performed on the results of docked protein-ligand complexes to identify top ranking molecules against the modelled 3D structure of SmCL1. MD simulation results suggest the phytochemical Simalikalactone-D as a potential lead against SmCL1, whose pharmacophore model may be useful for future screening of potential drug molecules. To conclude, this is the first report to discuss the virtual screening of non-peptide inhibitors against SmCL1 of S. mansoni, with significant therapeutic potential. Results presented herein provide a valuable contribution to identify the significant leads and further derivatize them to suitable drug candidates for antischistosomal therapy.

  1. 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.

  2. The impact of zinc supplementation on Schistosoma mansoni reinfection rate and intensities

    DEFF Research Database (Denmark)

    Friis, Henrik; Ndhlovu, P; Mduluza, T;

    1997-01-01

    OBJECTIVES: To assess the effect of zinc supplementation on susceptibility to S. mansoni reinfections among schoolchildren. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING AND SUBJECTS: 313 rural Zimbabwean schoolchildren (144 boys and 169 girls), 11-17 y). INTERVENTIONS......: Supplementation with zinc (30 or 50 mg) or placebo on schooldays for 12 months. Due to drought, a food programme was in operation during the last eight months of the study. OUTCOME MEASURES: S. mansoni and S. haematobium reinfection rates and intensities. RESULTS: There was no difference in reinfection rates...... rates or intensities were seen. CONCLUSIONS: Zinc supplementation reduced the intensity of S. mansoni reinfections. Although the intensities of reinfection were very low, the finding probably reflects a biological effect of zinc that could be of public health importance in settings with higher...

  3. 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

    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...... elemental iron twice-weekly for 12 months had significantly lower reinfection rates of A. lumbricoides (16.7% vs 31.9%, P = 0.046), T. trichiura (6.9% vs 20.6%, P = 0.03) and S. mansoni (38.3% vs 61.8%, P = 0.008) compared to adults given placebo. In contrast, adults allocated to iron had a significantly...... 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...

  4. Compatibility of Ugandan Schistosoma mansoni isolates with Biomphalaria snail species from Lake Albert and Lake Victoria

    DEFF Research Database (Denmark)

    Adriko, Moses; Standley, Claire J.; Tinkitina, Benjamin;

    2013-01-01

    In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non......-sympatric S. mansoni isolates. After a prepatent period of 20 days, a daily 10-hourly snail shedding for cercariae was done to determine the infection rate, cercarial production per hour and survival period of infected snails. The study suggests that when parasite strains from a different geographical origin...... is used for infection, survival of infected snails increase, leading to an increased transmission potential. Although earlier literature had indicated that the Lake Victoria Biomphalaria sudanica is refractory to S. mansoni, we showed that all Ugandan Biomphalaria spp., including B. sudanica from all...

  5. The genome of the blood fluke Schistosoma mansoni

    Science.gov (United States)

    Berriman, Matthew; Haas, Brian J.; LoVerde, Philip T.; Wilson, R. Alan; Dillon, Gary P.; Cerqueira, Gustavo C.; Mashiyama, Susan T.; Al-Lazikani, Bissan; Andrade, Luiza F.; Ashton, Peter D.; Aslett, Martin A.; Bartholomeu, Daniella C.; Blandin, Gaelle; Caffrey, Conor R.; Coghlan, Avril; Coulson, Richard; Day, Tim A.; Delcher, Art; DeMarco, Ricardo; Djikeng, Appoliniare; Eyre, Tina; Gamble, John A.; Ghedin, Elodie; Gu, Yong; Hertz-Fowler, Christiane; Hirai, Hirohisha; Hirai, Yuriko; Houston, Robin; Ivens, Alasdair; Johnston, David A.; Lacerda, Daniela; Macedo, Camila D.; McVeigh, Paul; Ning, Zemin; Oliveira, Guilherme; Overington, John P.; Parkhill, Julian; Pertea, Mihaela; Pierce, Raymond J.; Protasio, Anna V.; Quail, Michael A.; Rajandream, Marie-Adèle; Rogers, Jane; Sajid, Mohammed; Salzberg, Steven L.; Stanke, Mario; Tivey, Adrian R.; White, Owen; Williams, David L.; Wortman, Jennifer; Wu, Wenjie; Zamanian, Mostafa; Zerlotini, Adhemar; Fraser-Liggett, Claire M.; Barrell, Barclay G.; El-Sayed, Najib M.

    2009-01-01

    Schistosoma mansoni is responsible for the neglected tropical disease schistosomiasis that affects 210 million people in 76 countries. We report here analysis of the 363 megabase nuclear genome of the blood fluke. It encodes at least 11,809 genes, with an unusual intron size distribution, and novel families of micro-exon genes that undergo frequent alternate splicing. As the first sequenced flatworm, and a representative of the lophotrochozoa, it offers insights into early events in the evolution of the animals, including the development of a body pattern with bilateral symmetry, and the development of tissues into organs. Our analysis has been informed by the need to find new drug targets. The deficits in lipid metabolism that make schistosomes dependent on the host are revealed, while the identification of membrane receptors, ion channels and more than 300 proteases, provide new insights into the biology of the life cycle and novel targets. Bioinformatics approaches have identified metabolic chokepoints while a chemogenomic screen has pinpointed schistosome proteins for which existing drugs may be active. The information generated provides an invaluable resource for the research community to develop much needed new control tools for the treatment and eradication of this important and neglected disease. PMID:19606141

  6. Activity of the artemether in experimental schistosomiasis mansoni

    Directory of Open Access Journals (Sweden)

    Neusa Araújo

    1991-01-01

    Full Text Available The action of the ether artemisinin (artemether on Shistosoma mansoni in mice and the hansters experimentally infected with the LE strain was studied. In mice, the drugs showed high schistosomicidal activity using a single intramuscular dose of 100 mg/Kg/day. By the oral route, this dose showed a low activity. Mice treated with a single intramuscular dose of 200 mg/Kg/day, and examined 15 days after treatment, presented 100% alteration of the oogram; when examined 45 days after treatment, the oogram was normal. With doses of 100 mg/Kg/day, i.m., during 3 or 5 consecutive days, the death rate of mice was very high. Morphologic analysis of the worms collected by perfusion of mice treated with a single dose of 100 mg/Kg/day, i.m., detected a marked decrease in the length of male and female forms, degenerative alterations in the parenchyma and in the reproductive system of the females, with reduction of vitellinic material and in ovary volume; the intestinal contents presented a marked despigmentation. In the male worms signifcant alteration was not apparent by optical microscopy.

  7. The changing pattern of pathology due to Schistosoma mansoni infection

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    Zilton A. Andrade

    1985-09-01

    Full Text Available A survey of the autopsy data on hepatosplenic schistosomiasis during periods, before and after the advent of new chemotherapeutic drugs, revealed that: a the pathological presentation was the same for the two periods; b the number of cases in the last five years is progressively decreasing; c hepatosplenic disease due to schistosomiasis is becoming rare in young people. These data represent a change in the pattern of pathology in schistosomiasis, probably related to new chemotherapy.Uma revisão dos dados de necrópsias realizadas em portadores da forma hépato-esplênica da esquistossomose, feita em dois períodos, antes e após a introdução das novas e efetivas drogas contra o S. mansoni, revelou que: a as lesões encontradas foram qualitativamente as mesmas nos dois períodos; b a percentagem dos casos hépato-esplênicos mostra decréscimo progressivo nos últimos cinco anos do estudo; c os casos de esquistossomose hépato-esplênica estão se tornando raros em jovens. Tais elementos constituem uma mudança no padrão de apresentação da doença, possivelmente relacionada com a introdução da nova quimioterapia curativa.

  8. Stability of Schistosoma mansoni progeny to antischistosomal drugs

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    Luiz Candido de Souza Dias

    1985-08-01

    Full Text Available The susceptibility of the MAP Brazilian strain (F1 to F5 progenies of S. mansoni to four antischistosomal drugs has been reported in a previous study. In the present investigation, progeny F14 of the same strain, was tested for stability to the same 4 drugs. A new medication, Oltipraz (35,972 RP, was added to the study. Five groups of 12 mice infected with cercariae by tail immersion were treated with hycanthone, oxamniquine, niridazole, praziquantel and Oltipraz. An untreated group was used as control. Schistosomal activity was assessed by the localization of worms in the portal vein system, by oogram changes, and percentage of parasite reduction. The stability of the susceptibility of progeny F14 did not change in relation to generations F1 to F5; the progeny was resistant to hycanthone and oxamniquine; but sensitive to niridazole, praziquantel and Oltipraz. We emphasize the importance of the phenomenon of resistance of the worm in view of the fact that oxamniquine has been widely used in Brazilian areas where mansonic schistosomiasis is endemic.

  9. UVB-induced immune suppression and infection with Schistosoma mansoni

    Energy Technology Data Exchange (ETDEWEB)

    Noonan, F.P.; Lewis, F.A. [George Washington Univ., Washington, DC (United States). School of Medicine]|[Biomedical Research Inst., Rockville, MD (United States)

    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{sup 2}. Worm and egg burdens, liver granuloma diameters and liver fibrosis showed minimal changes (< 20%) compared with parameters in unirradiated animals. Ultraviolet irradiation (a total of 55 kJ/m{sup 2} administered in six treatments) did not impair the resistance to rechallenge conferred by vaccination with {sup 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).

  10. Schistosomiasis mansoni in low transmission areas: abdominal ultrasound

    Directory of Open Access Journals (Sweden)

    R Ruiz

    2002-10-01

    Full Text Available In endemic areas with low prevalence and low intensity of infection, the diagnosis of hepatic pathology due to the Schistosoma mansoni infection is very difficult. In order to establish the hepatic morbidity, a double-blind study was achieved in Venezuelan endemic areas, with one group of patients with schistosomiasis and the other one of non-infected people, that were evaluated clinically and by abdominal ultrasound using the Cairo classification. Schistosomiasis diagnosis was established based on parasitologic and serological tests. The increase of the hepatic size at midclavicular and midsternal lines (in hepatometry and the hard liver consistency were the clinical parameters able to differentiate infected persons from non infected ones, as well as the presence of left lobe hepatomegaly detected by abdominal ultrasound. The periportal thickening, especially the mild form, was frequent in all age groups in both infected and uninfected patients. There was not correlation between the intensity of infection and ultrasound under the current circumstances. Our data suggest that in Venezuela, a low endemic area of transmission of schistosomiasis, the hepatic morbidity is mild and uncommon. The Cairo classification seems to overestimate the prevalence of periportal pathology. The specificity of the method must be improved, especially for the recognition of precocious pathology. Other causes of hepatopathies must be investigated.

  11. Magnetic resonance imaging and ultrasound in hepatosplenic schistosomiasis mansoni Ressonância magnética e ultrassonografia na esquistossomose mansoni hepatoesplênica

    OpenAIRE

    José Roberto Lambertucci; Luciana Cristina dos Santos Silva; Luciene Mota Andrade; Leonardo Campos de Queiroz; Rogério Augusto Pinto-Silva

    2004-01-01

    We report the findings of abdominal ultrasound and magnetic resonance imaging observed in a patient with advanced schistosomiasis mansoni. A 25-year-old man with hepatosplenic schistosomiasis and variceal bleeding confirmed by upper endoscopy was submitted to abdominal ultrasound and magnetic resonance imaging. During surgery for portal hypertension, a liver biopsy was taken and the diagnosis of Symmers' fibrosis was confirmed. magnetic resonance imaging scans gave more precise information ab...

  12. The prolonged use of niclosamide as a molluscicide for the control of Schistosoma mansoni Uso prolongado da niclosamida como moluscicida para o controle do Schistosoma mansoni

    OpenAIRE

    Pedro Coura-Filho; Nelymar Martinelli Mendes; Cecilia Pereira de Souza; José Pedro Pereira

    1992-01-01

    Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG). All the residents of the area were submitted to an annual fecal examination (Kato/Katz) and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks ...

  13. Congenital and nursing effects on the evolution of Schistosoma mansoni infection in mice

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    J. A. Lenzi

    1987-01-01

    Full Text Available Modification of the immune response to schistosomal infection in children or offspring born to mother R infected with Schistosoma mansoni has been demonstrated in human and in experimental schistosomiasis. One of the hypothesis to explain this fact could be the transfer of circulating antigens and antibodies from mother to foetus through the placenta or from mother to child by milk. The results of this spontaneous transference are controversial in the literature. In an attempt to investigate these questions, we studied one hundred and twenty offspring (Swiss mice, sixty born to infected-mothers (group A and sixty born to non-infected mothers (group B. These were percutaneously infected with 50 cercariae/mouse, and divided in six sub-groups (20 mice/sub-group, according to the following schedule: after birth (sub-groups A.I and B.I, 10 days old (sub-groups A.II and B.II and 21 days old (sub-groups A.III and B.III. After the exposure period, the young mice returned to their own mothers for nursing. Six weeks later, the mice were killed. We obtained the following results: 1 There is transference of antibody to cercariae (CAP, adult worms (SWAP and egg antigens (SEA from the infected mothers to the offspring, probably through placenta and milk; 2 Offspring born to infected mothers exhibit much less coagulative hepatic necrosis and show a lower number of eggs in the small intestine and a less intense and predominant exsudative stage of the hepatic granulomas when compared with the exsudative-productive stage of the control groups. The findings suggest that congenital and nursing factors can interfere on the development of the schistosomiasis infection, causing an hyporesponse to the eggs.

  14. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice

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    Rafaella Fortini Queiroz Grenfell

    2012-08-01

    Full Text Available INTRODUCTION: The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. METHODS: Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA assays were compared with the number of worms counted and the IgG titers at different times of infection. RESULTS: Data showed that ELISA using adult worm antigens (ELISA-SWAP presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62. In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively, whereas ELISA using egg antigens (ELISA-SEA detected samples after 140 days (p=0.03. CONCLUSIONS: These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  15. BLOCKADE OF PGE2, PGD2 RECEPTORS CONFERS PROTECTION AGAINST PREPATENT SCHISTOSOMIASIS MANSONI IN MICE.

    Science.gov (United States)

    Abdel-Ghany, Rasha; Rabia, Ibrahim; El-Ahwany, Eman; Saber, Sameh; Gamal, Rasha; Nagy, Faten; Mahmoud, Olaa; Hamad, Rabab Salem; Barakat, Walled

    2015-12-01

    Schistosomiasis is a chronic disease with considerable social impact. Despite the availability of affordable chemotherapy, drug treatment has not significantly reduced the overall number of disease cases. Among other mechanisms, the parasite produces PGE2 and PGD2 to evade host immune defenses. To investigate the role of PGE2 and PGD2 in schistosomiasis, we evaluated the effects of L-161,982, Ah6809 (PGE2 receptor antagonists alone of combined with each other) and MK-0524 (PGD2 receptor antagonist) during prepatent Schistosoma mansoni infection. Drugs were administered intraperitoneally an hour before and 24 hours after infection of C57BL/6 mice with 100 Schistosoma mansoni cercariae. L-161,982, Ah6809, their combination and MK-0524 caused partial protection against pre-patent S. mansoni infection which was mediated by biasing the immune response towards Th1 phenotype. These results showed that blockade of PGE2 and PGD2 receptors confers partial protection against pre-patent S. mansoni infection in mice and that they may be useful as adjunctive therapy to current anti-schistosomal drugs or vaccines. PMID:26939228

  16. Immunoproteomic Analysis of the Excretory-Secretory Proteins from Spirometra mansoni Sparganum

    Science.gov (United States)

    HU, Dan Dan; CUI, Jing; WANG, Li; LIU, Li Na; WEI, Tong; WANG, Zhong Quan

    2013-01-01

    Background Sparganosis is caused by the invasion of Spirometra sparganum into various tissues/organs. Subcutaneous sparganosis can be diagnosed by biopsy, while visceral/cerebral sparganosis is not easy to be diagnosed. The diagnosis depends largely on the detection of specific anti-sparganum antibodies. The specificity of the ELISA could be increased by using S. mansoni sparganum excretory–secretory (ES) antigens, but it also had the cross-reactions with sera of patients with cysticercosis or paragonimiasis. The aim of this study was to identify early specific diagnostic antigens in S. mansoni sparganum ES proteins. Methods The sparganum ES proteins were analyzed by two-dimensional electrophoresis (2-DE) and Western blot probed with early sera from infected mice at 14 days post-infection. The immunoreactive protein spots were characterized by MALDI-TOF/ TOF-MS. Results A total of approximately 149 proteins spots were detected with isoelectric point (pI) varying from 3 to 7.5 and molecular weight from 20 to 115 kDa and seven protein spots with molecular weight of 23-31 kDa were recognized by the infection sera. Three of seven spots were successfully identified and characterized as the same S. mansoni protein (cysteine protease), and the proteins of other 4 spots were not included in the databases. Conclusion The cysteine protease from S. mansoni ES proteins recognized by early infection sera might be the early diagnostic antigens for sparganosis. PMID:24454434

  17. The effect of praziquantel against Schistosoma mansoni-infections in Botswana

    DEFF Research Database (Denmark)

    Friis, H; Byskov, Jens

    1989-01-01

    Chemotherapy of all infected individuals, using praziquantel 40 mg/kg in a single dose, was the initial component of the recently introduced control programme against Schistosoma mansoni-infections in Ngamiland, Botswana. To evaluate the effect of praziquantel in Ngamiland, 81 children were...

  18. Experimental evaluation of Candonocypris novaezelandiae (Crustacea: Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

    Science.gov (United States)

    Yousif, Fouad; Hafez, Sherif; El Bardicy, Samia; Tadros, Menerva; Taleb, Hoda Abu

    2013-01-01

    Objective To test Candonocypris novaezelandiae (Baird) (C. novaezelandiae), sub-class Ostracoda, obtained from the Nile, Egypt for its predatory activity on snail, Biomphalaria alexandrina (B. alexandrina), intermediate host of Schistosoma mansoni (S. mansoni) and on the free-living larval stages of this parasite (miracidia and cercariae). Methods The predatory activity of C. novaezelandiae was determined on B. alexandrina snail (several densities of eggs, newly hatched and juveniles). This activity was also determined on S. mansoni miracidia and cercariae using different volumes of water and different numbers of larvae. C. novaezelandiae was also tested for its effect on infection of snails and on the cercarial production. Results C. novaezelandiae was found to feed on the eggs, newly hatched and juvenile snails, but with significant reduction in the consumption in the presence of other diet like the blue green algae (Nostoc muscorum). This ostracod also showed considerable predatory activity on the free-living larval stages of S. mansoni which was affected by certain environmental factors such as volume of water, density of C. novaezelandiae and number of larvae of the parasite. Conclusions The presence of this ostracod in the aquatic habitat led to significant reduction of snail population, infection rate of snails with schistosme miracidia as well as of cercarial production from the infected snails. This may suggest that introducing C. novaezelandiae into the habitat at schistosome risky sites could suppress the transmission of the disease. PMID:23620849

  19. Effect of bee venom or proplis on molecular and parasitological aspects of Schistosoma mansoni infected mice.

    Science.gov (United States)

    Mohamed, Azza H; Hassab El-Nabi, Sobhy E; Bayomi, Asmaa E; Abdelaal, Ahmed A

    2016-06-01

    The present study was performed to elucidate the efficacy of Apis mellifera L bee venom (BV) or proplis (200 mg/kg orally for three consecutive days) on Schistosoma mansoni infected mice. The results recorded reduction in the total worm burden, numbers of immature eggs and the ova count in hepatic tissue in BV (sting or injection) or proplis treated groups as compared to the infected group. Histological examination illustrated a significant increase (P ≤ 0.05) in the diameter of hepatic granuloma in BV treated groups (272.78 and 266.9, respectively) and a significant decrease in proplis treated mice (229.35) compared with the infected group (260.67). Electrophoretic pattern of RNA showed a decrease in mean of maximal optical density in liver and intestine of S. mansoni infected mice treated with bee venom (sting or injection) as compared with infected group. Flow cytometry analyses of RNA or apoptotic percentage of worms recovered from BV sting (19 and 49 % respectively); BV injected (20.5 and 51.17 %, respectively) and proplis (35 and 23.93 %, respectively) groups were compared with S. mansoni infected group (37.87 and 39.21 %, respectively). It can be concluded that administration of bee venom or proplis are effective in case of S. mansoni infection. Although bee venom cause increase of granuloma diameter and this might be due to venom concentration and further studies are required to avoid such harmful effect. PMID:27413311

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

    NARCIS (Netherlands)

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

    1987-01-01

    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

  1. Hybridism between Biomphalaria cousini and Biomphalaria amazonica and its susceptibility to Schistosoma mansoni

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    Tatiana Maria Teodoro

    2011-11-01

    Full Text Available Molecular techniques can aid in the classification of Biomphalaria species because morphological differentiation between these species is difficult. Previous studies using phylogeny, morphological and molecular taxonomy showed that some populations studied were Biomphalaria cousini instead of Biomphalaria amazonica. Three different molecular profiles were observed that enabled the separation of B. amazonica from B. cousini. The third profile showed an association between the two and suggested the possibility of hybrids between them. Therefore, the aim of this work was to investigate the hybridism between B. cousini and B. amazonica and to verify if the hybrids are susceptible to Schistosoma mansoni. Crosses using the albinism factor as a genetic marker were performed, with pigmented B. cousini and albino B. amazonica snails identified by polymerase chain reaction-restriction fragment length polymorphism. This procedure was conducted using B. cousini and B. amazonica of the type locality accordingly to Paraense, 1966. In addition, susceptibility studies were performed using snails obtained from the crosses (hybrids and three S. mansoni strains (LE, SJ, AL. The crosses between B. amazonica and B. cousini confirmed the occurrence of hybrids. Moreover, hybrids can be considered potential hosts of S. mansoni because they are susceptible to LE, SJ and AL strains (4.4%, 5.6% and 2.2%, respectively. These results indicate that there is a risk of introducing schistosomiasis mansoni into new areas.

  2. C-type lectin interactions with Schistosoma mansoni SEA : Molecular basis and function

    NARCIS (Netherlands)

    Liempt, van P.A.G.

    2007-01-01

    Outline of this thesis The studies described in this thesis have been performed to gain more insight in the recognition of Schistosoma mansoni glycans by C-type lectins and the consequences for dendritic cell mediated immune responses. As a first approach to understand the molecular interactions o

  3. Experimental evaluation of Candonocypris novaezelandiae (Crustacea:Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

    Institute of Scientific and Technical Information of China (English)

    Fouad Yousif; Sherif Hafez; Samia El Bardicy; Menerva Tadros; Hoda Abu Taleb

    2013-01-01

    Objective: To test Candonocypris novaezelandiae (Baird) (C. novaezelandiae), sub-class Ostracoda, obtained from the Nile, Egypt for its predatory activity on snail, Biomphalariaalexandrina (B. alexandrina), intermediate host of Schistosoma mansoni (S. mansoni) and on the free-living larval stages of this parasite (miracidia and cercariae). Methods:The predatory activity of C. novaezelandiae was determined on B. alexandrina snail (several densities of eggs, newly hatched and juveniles). This activity was also determined on S. mansoni miracidia and cercariae using different volumes of water and different numbers of larvae. C. novaezelandiae was also tested for its effect on infection of snails and on the cercarial production. Results: C. novaezelandiae was found to feed on the eggs, newly hatched and juvenile snails, but with significant reduction in the consumption in the presence of other diet like the blue green algae (Nostoc muscorum). This ostracod also showed considerable predatory activity on the free-living larval stages of S. mansoni which was affected by certain environmental factors such as volume of water, density of C. novaezelandiae and number of larvae of the parasite.Conclusions:The presence of this ostracod in the aquatic habitat led to significant reduction of snail population, infection rate of snails with schistosme miracidia as well as of cercarial production from the infected snails. This may suggest that introducing C. novaezelandiae into the habitat at schistosome risky sites could suppress the transmission of the disease.

  4. Genetic knockdown and pharmacological inhibition of parasite multidrug resistance transporters disrupts egg production in Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Ravi S Kasinathan

    2011-12-01

    Full Text Available P-glycoprotein (Pgp and multidrug resistance-associated proteins (MRPs are ATP-dependent transporters involved in efflux of toxins and xenobiotics from cells. When overexpressed, these transporters can mediate multidrug resistance (MDR in mammalian cells, and changes in Pgp expression and sequence are associated with drug resistance in helminths. In addition to the role they play in drug efflux, MDR transporters are essential components of normal cellular physiology, and targeting them may prove a useful strategy for development of new therapeutics or of compounds that enhance the efficacy of current anthelmintics. We previously showed that expression of Schistosoma mansoni MDR transporters increases in response to praziquantel (PZQ, the current drug of choice against schistosomiasis, and that reduced PZQ sensitivity correlates with higher levels of these parasite transporters. We have also shown that PZQ inhibits transport by SMDR2, a Pgp orthologue from S. mansoni, and that PZQ is a likely substrate of SMDR2. Here, we examine the physiological roles of SMDR2 and SmMRP1 (the S. mansoni orthologue of MRP1 in S. mansoni adults, using RNAi to knock down expression, and pharmacological agents to inhibit transporter function. We find that both types of treatments disrupt parasite egg deposition by worms in culture. Furthermore, administration of different MDR inhibitors to S. mansoni-infected mice results in a reduction in egg burden in host liver. These schistosome MDR transporters therefore appear to play essential roles in parasite egg production, and can be targeted genetically and pharmacologically. Since eggs are responsible for the major pathophysiological consequences of schistosomiasis, and since they are also the agents for transmission of the disease, these results suggest a potential strategy for reducing disease pathology and spread.

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

    Directory of Open Access Journals (Sweden)

    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

  6. Aspectos imunológicos do sistema enzimático fenoloxidase de Schistosoma mansoni Immunological aspects of the phenol oxidase enzymatic system of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    João Tadeu Ribeiro-Paes

    1994-10-01

    Full Text Available O sistema enzimático fenoloxidase (EC 1.10.3.1, EC 1.10.3.2 está amplamente distribuido entre os seres vivos, tendo sido descrito em diferentes espécies do reino animal e vegetal. Apesar de desempenhar um papel fundamental na formação da cápsula ou parede dos ovos de trematódeos, o sistema enzimático fenoloxidase (PO tem sido pouco estudado nesses organismos. No presente trabalho são apresentados os resultados iniciais de imunizações de coelhos contra PO de fêmeas adultas de S. mansoni e tirosinase de cogumelo (Sigma. As análises imunológicas, realizadas através de imunodifusão dupla (teste de Ouchterlony e imunoeletroforese, revelaram identidade imunitária parcial entre a PO de machos e fêmeas. Não se observou reação cruzada entre os antissoros de coelhos imunizados contra PO e aqueles com tirosinase, indicando que, embora os sítios catalíticos de ambas as enzimas devam ser semelhantes, já que atuam sobre os mesmos substratos, os determinantes antigênicos devem ser diferentes. Os resultados descritos no presente trabalho representam um primeiro passo no sentido da purificação das isoenzimas da fenoloxidase e sua posterior utilização ao estudo dos mecanismos moleculares envolvidos na esclerotização da parede dos ovos de S. mansoni.The phenol oxidase enzymatic system (EC 1.10.3.1, EC 1.10.3.2 is widespread in different species of the animal and vegetal kingdom. Despite its importance in the eggshell formation of the trematodes phenol oxidase (PO has been little studied in these organisms, mainly in S. mansoni. This report presents the initial results concerning the immunization of rabbits with PO of S. mansoni and mushroom tyrosinase. The immunological analysis done by means of double immu-nodifusion (Ouchterlony and immunoelectrophoresis techniques revealed some immunological identity between the PO of males and females. It was not seen cross reaction between the antisera against PO and tyrosinase, what suggests

  7. Esquistossomose mansônica em vesícula seminal Schistosomiasis mansoni in the seminal vesicle

    Directory of Open Access Journals (Sweden)

    Eduardo José Andrade Lopes

    2007-06-01

    Full Text Available Em regiões endêmicas, a esquistossomose mansônica é responsável por uma alta taxa de morbimortalidade por doenças associadas à infestação do sistema hepático. O acometimento genital pela schistosomiasis mansoni é raro. Nós relatamos o primeiro caso de esquistossomose mansônica em vesícula seminal diagnosticado, incidentalmente, pelo exame histopatológico da próstata e vesículas seminais removidos cirurgicamente.In endemic regions, Mansoni schistosomiasis is responsible for high morbidity-mortality rates due to diseases associated with infestation of the hepatic system. Genital involvement caused by Mansoni schistosomiasis is rare. We report the first case of Mansoni schistosomiasis in the seminal vesicle, which was diagnosed incidentally by means of histopathological study of the prostate and seminal vesicles after surgical removal.

  8. Changes in IgE- and Antigen-dependent histamine-release in peripheral blood of Schistosoma mansoni-infected Ugandan fishermen after treatment with praziquantel

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    Kazibwe Francis

    2004-04-01

    Full Text Available Abstract Background Parasite-specific IgE levels correlate with human resistance to reinfection with Schistosoma spp. after chemotherapy. Although the role of eosinophils in schistosomiasis has been the focus of a great deal of important research, the involvement of other Fcε receptor-bearing cells, such as mast cells and basophils, has not been investigated in relation to human immunity to schistosomes. Chemotherapy with praziquantel (PZQ kills schistosomes living in an in vivo blood environment rich in IgE, eosinophils and basophils. This releases parasite Ags that have the potential to cross-link cell-bound IgE. However, systemic hypersensitivity reactions are not induced by treatment. Here, we describe the effects of schistosomiasis, and its treatment, on human basophil function by following changes in total cellular histamine and in vitro histamine-release induced by schistosome Ags or anti-IgE, in blood samples from infected Ugandan fishermen, who are continuously exposed to S. mansoni infection, before and 1-day and 21-days after PZQ treatment. Results There was a significant increase in the total cellular histamine in blood samples at 1-day post-treatment, followed by a very significant further increase by 21-days post-treatment. In vitro histamine-release induced by S. mansoni egg (SEA or worm (SWA Ags or anti-IgE antibody, was significantly reduced 1-day post-treatment. The degree of this reduction correlated with pre-treatment infection intensity. Twenty-1-days post-treatment, SEA-induced histamine-release was still significantly lower than at pretreatment. Histamine-release was not correlated to plasma concentrations of total or parasite-specific IgE, nor to specific IgG4 plasma concentrations. Conclusion The biology of human blood basophils is modulated by S. mansoni infection and praziquantel treatment. Infection intensity-dependent suppression of basophil histamine-release, histamine-dependent resistance to infection, and

  9. Soil-Transmitted Helminths and Schistosoma mansoni Infections in Ethiopian Orthodox Church Students around Lake Tana, Northwest Ethiopia

    Science.gov (United States)

    Afework Bitew, Aschalew; Abera, Bayeh; Seyoum, Walle; Endale, Befekadu; Kiber, Tibebu; Goshu, Girma; Admass, Addiss

    2016-01-01

    Background Soil-transmitted helminths (STH) and Schistosoma mansoni infections are the major neglected tropical diseases that result in serious consequences on health, education and nutrition in children in developing countries. The Ethiopian Orthodox church students, who are called Yekolotemari in Amharic, live in areas with poor sanitation and hygiene. Moreover, they are not included in the national STH control programs. Thus, STH and S. mansoni infections prevalence is unknown. Methods A cross-sectional study was conducted on 384 students in June 2014 to determine STH and S. mansoni infections prevalence. Moreover, the knowledge of students about STH and S. mansoni was assessed. Data on knowledge and clinical symptoms were collected using structured questionnaires via face to face interview. Stool specimens were examined by formol-ether concentration method. Results The overall prevalence of intestinal helminths infections was 85.9% (95% confidence interval (CI): 82.1–89%). STHs infections prevalence was 65.6% (95% CI: 60.7–70.2%). The prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura were 31.8% (95% CI: 27.3–36.6%), 29.4% (25–31%) and 3.1% (1.8–5.4%), respectively. On the other hand, S. mansoni prevalence was 14.3% (95% CI: 11.1–18.1%). Majority of students infected with S. mansoni had bloody stool with crud odds-ratio of 2.9 (95% CI: 1.5–5.5). Knowledge assessment showed that 50 (13%) and 18 (4.9%) of the respondents knew about transmission of STH and S. mansoni, respectively. Conclusions The prevalence of STH and S. mansoni infections were high thus de-worming program should include the students of Ethiopian Orthodox churches. Furthermore, provision and use of sanitary facilities, health education for students to create awareness of parasitic infections and improved personal hygiene should be in place. PMID:27203749

  10. Assessment of Vaccination with Schistosomules Attenuated by Using Different Doses of γ-Radiation on Experimental Schistosomiasis Mansoni

    International Nuclear Information System (INIS)

    Schistosomiasis is a major public health problem that affects mainly developing countries. There are 200 million people worldwide infected with schistosomes resulting in more than 250,000 deaths per year (Pacifico et al., 2006). Approximately 85% of the 200 million people infected with schistosomiasis inhabit sub-Saharan Africa (Mungadi and Malami, 2007). It is one of the most important human diseases causing damage for economy and man power in the area where it prevails (Pyrrho et al., 2004). In Egypt, it is one of the major public health problems (El-Khoby et al., 2000). In 1998 El-Khoby et al., reported that at mid 1996 about six million Egyptians infected with a prevalence rate of 11.9% and 5.5% for Schistosoma mansoni and Schistosoma haematobium respectively. It was estimated by the ministry of health in 2002 to be below 5% although some independent researchers were still insisting prevalence was higher in hot villages (Hanna et al., 2005). In human, the nature of the disease is largely immunological and only indirectly due to the parasitic worm itself. The pathological lesions emanate from inflammatory reactions to the large number of parasite eggs which are retained in host tissues rather than excreted with the faeces or urine to infect the snail (Yang, 2008). Its pathology is to create a granulomatous reaction towards the egg that failed to be excreted by the host. The resulting fibrosis can cause hepatomegally in the liver (Moawad, 2003)

  11. Accuracy of urine circulating cathodic antigen (CCA test for Schistosoma mansoni diagnosis in different settings of Cote d'Ivoire.

    Directory of Open Access Journals (Sweden)

    Jean T Coulibaly

    2011-11-01

    Full Text Available BACKGROUND: Promising results have been reported for a urine circulating cathodic antigen (CCA test for the diagnosis of Schistosoma mansoni. We assessed the accuracy of a commercially available CCA cassette test (designated CCA-A and an experimental formulation (CCA-B for S. mansoni diagnosis. METHODOLOGY: We conducted a cross-sectional survey in three settings of Côte d'Ivoire: settings A and B are endemic for S. mansoni, whereas S. haematobium co-exists in setting C. Overall, 446 children, aged 8-12 years, submitted multiple stool and urine samples. For S. mansoni diagnosis, stool samples were examined with triplicate Kato-Katz, whereas urine samples were tested with CCA-A. The first stool and urine samples were additionally subjected to an ether-concentration technique and CCA-B, respectively. Urine samples were examined for S. haematobium using a filtration method, and for microhematuria using Hemastix dipsticks. PRINCIPAL FINDINGS: Considering nine Kato-Katz as diagnostic 'gold' standard, the prevalence of S. mansoni in setting A, B and C was 32.9%, 53.1% and 91.8%, respectively. The sensitivity of triplicate Kato-Katz from the first stool and a single CCA-A test was 47.9% and 56.3% (setting A, 73.9% and 69.6% (setting B, and 94.2% and 89.6% (setting C. The respective sensitivity of a single CCA-B was 10.4%, 29.9% and 75.0%. The ether-concentration technique showed a low sensitivity for S. mansoni diagnosis (8.3-41.0%. The specificity of CCA-A was moderate (76.9-84.2%; CCA-B was high (96.7-100%. The likelihood of a CCA-A color reaction increased with higher S. mansoni fecal egg counts (odds ratio: 1.07, p<0.001. A concurrent S. haematobium infection or the presence of microhematuria did not influence the CCA-A test results for S. mansoni diagnosis. CONCLUSION/SIGNIFICANCE: CCA-A showed similar sensitivity than triplicate Kato-Katz for S. mansoni diagnosis with no cross-reactivity to S. haematobium and microhematuria. The low sensitivity

  12. Esquistossomose mansoni em duas mesorregiões do Estado de Alagoas Schistosomiasis mansoni in two mesoregions of the State of Alagoas

    Directory of Open Access Journals (Sweden)

    Janira Lúcia Assumpção Couto

    2005-08-01

    Full Text Available No Brasil, índices elevados da esquistossomose mansônica correspondem, na grande maioria dos casos, à presença da espécie Biomphalaria glabrata, principal transmissora do Schistosoma mansoni, nas localidades endêmicas. Foi realizado estudo em 40 municípios endêmicos do Estado de Alagoas, com o objetivo de verificar a existência da espécie e sua importância na manutenção da esquistossomose nesse Estado. Desses municípios, 28 são pertencentes à mesorregião do leste Alagoano e 12 à mesorregião do Agreste Alagoano. Os moluscos procederam de diversos tipos de criadouros: riachos, córregos, valas, açudes, brejos e poços. As coletas foram realizadas no período de fevereiro de 1996 a dezembro de 1998. Para a identificação de Biomphalaria glabrata, foi efetuado o exame anatômico das partes moles, após remoção das conchas. A detecção de cercárias do Schistosoma mansoni foi realizada através da técnica de esmagamento, calculando-se o percentual de infecção. Em 32 (80% dos municípios estudados foi encontrada Biomphalaria glabrata, seis deles apresentando moluscos infectados com cercárias do parasita. Penedo apresentou a maior (6,6% taxa de infecção, seguindo-se Ibateguara (5,6%. Taxas menores foram observadas em Chã Preta (2,7%, em Murici (2,5%, Porto Real do Colégio (0,1% e Igreja Nova (0,1%. O inquérito copro-parasitológico efetuado pela Fundação Nacional de Saúde em 1997, 1998/1999 e 2000, confirmou a importância da endemia nessas regiões do Estado.In Brazil, high levels of schistosomiasis mansoni are linked to the presence of the species Biomphalaria glabrata, considered to be the main host of Schistosoma mansoni in endemic areas. This work conducted a survey of 40 endemic municipalities in the State of Alagoas, aiming at identifying this species and its important role in the maintenance of schistosomiasis. Among the municipalities surveyed, 28 lie in the mesoregion of the Leste Alagoano and 12, in the

  13. Comportamento da cepa LE de Schistosoma mansoni, após passagem em hospedeiro humano infectado acidentalmente

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    Neusa Araújo

    1986-12-01

    Full Text Available Uma auxiliar de laboratório infectou-se acidentalmente, com cercárias de Schistosoma mansoni, cepa LE, mantida rotineiramente em nossos laboratórios. Decorridos 5 meses, o exame parasitológico de fezes revelou 108 ovos/g . A pacientefoi tratada com oxamniquine, porém a infecção continuou ativa (6 ovos/g. Foi então obtido o isolado SSF mantido no modelo Biomphalaria glabrata - camundongo albino. Os resultados obtidos no estudo comparativo, entre o isolado SSF e a cepa LE, que lhe deu origem, mostraram que a duração do período pré-patente e o índice de infectividade em camundongos, bem como a resposta aos agentes esquistossomicidas (hycanthone, oxamniquine epraziquantel não apresentaram diferenças estatisticamente significativas. Por outro lado, o número de miracídios obtidos dos intestinos e fígados dos camundongos infectados foi o dobro com a cepa LE, quando comparados com aquele do isolado SSF. Também a variação do peso dos animais foi bastante diferente. Concluiu-se que apenas uma passagem pelo hospedeiro humano não mudou substancialmente as características da cepa estudada.A laboratory technician was accidentally infected with the LE strain of Schistosoma mansoni cercariae maintained in our laboratories. After 5 months infection parasitological examination revealed 108 eggs/g faeces. Althrough treated with oxamniquine, the infection still persisted (6 eggs/g of faeces. An isolate (SSF was obtained from that person and maintained in Biomphalaria glabrata - Swiss mouse by alternate passage. The experimental comparative results between the newly obtained SSF isolate and the original LE strain showed that the differences in pre-patent period, the mice infectivity level and the schistosomicidal response to hycanthone, oxamniquine and praziquantel was not statistically significant. On the other hand the number of miracidia recovered from intestines and livers of equally infected mice was twice as miich in the LE strain than

  14. 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.

  15. Immunostimulatory effects of extract of Pulicaria crispa before and after Schistosoma mansoni infection.

    Science.gov (United States)

    Maghraby, Amany S; Shalaby, Nagwa; Abd-Alla, Howida I; Ahmed, Samia A; Khaled, Hussein M; Bahgat, Mahmoud M

    2010-01-01

    The immunostimulatory effects of methanolic extract from Pulicaria crispa were investigated in mice before and after infection with Schistosoma mansoni. Mice were subjected for daily intra-peritoneal injection by the extract (33 ng/mouse) for 10 successive days followed by infecting every mouse with 100 S. mansoni cercariae. Treatment with the extract induced significant increase (p < 0.05) in sera-IL-2 before and after infection. Upon using soluble worm antigen preparation or cancer bladder homogenates as antigens in ELISA, the detected levels of IgG were significantly (p < 0.05) higher in sera from treated-infected mice than untreated P. crispa infected mice. Using crude Escherichia coli lysate as an antigen in ELISA, it was detected a significant (p < 0.05) increase in IgG levels in sera from the extract-treated mice before and after infection.

  16. Dyarrheal Syndrome in a Patient Co-Infected with Leishmania infantum and Schistosoma mansoni

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    Gláucia Fernandes Cota

    2012-01-01

    Full Text Available This case report describes an atypical clinical presentation of visceral leishmaniasis affecting the digestive tract and causing malabsorption syndrome in a patient without recognized immunosuppressive condition. After appropriate treatment for the classical visceral form of the disease, diarrhea persisted as the main symptom and massive infection by Leishmania was detected by histopathology analysis of the duodenal mucosa. Schistosoma mansoni coinfection was also confirmed and treated without impact on diarrhea. New course of amphotericin B finally led to complete improvement of diarrhea. Atypical visceral leishmaniasis involving the gastrointestinal tract is well recognized in HIV coinfection but very rare in immunocompetent patients. The factors determining the control or evolution of the Leishmania infection have not been completely identified. This case stresses the importance of atypical symptoms and the unusual location of visceral leishmaniasis, not only in immunodepressed patients, and raises the possible influence of chronic infection by S. mansoni reducing the immune response to Leishmania.

  17. The growth and development of Schistosoma mansoni in mice exposed to sublethal doses of radiation

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    Aitken, R.; Wilson, R.A. (Univ. of York, Heslington (England))

    1989-12-01

    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.

  18. Application of synthetic peptides in development of a serologic method for laboratory diagnosis of schistosomiasis mansoni

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    Edward José de Oliveira

    2006-10-01

    Full Text Available The immunoreactivity of seven peptides synthesized from Schistosoma mansoni proteins, was evaluated by dot-blot and ELISA assays using two different sensitization methodologies. The best results were obtained on wells of the Costar 3590 microplates coated with peptides P1, P2, P3, P6, and P7 using conventional methodology. The signals increased considerably (p < 0.0003 on wells sensitized with P1 to P6 using alternative methodology. In contrast, the well coated with peptide P7 presented lower signal when compared with conventional methodology (p = 0.0019. These results, establish the basis for the application of synthetic peptides for laboratory diagnosis of schistosomiasis mansoni.

  19. Radicular dysfunction preponderance at early phase clinical evaluation in myelitis by Schistosoma mansoni

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    Claudio Henrique Fernandes Vidal

    2011-04-01

    Full Text Available In neuroschistosomiasis, the spinal cord is the most common place of the disease. In high prevalent areas for schistosomiasis mansoni, the clinical alertness is important for an early diagnostic, in order to decrease the final neurological damage. This study provides some useful neurologic information about a series of patients with schistosomal myelitis. METHOD: The sample consisted of 13 schistosomiasis mansoni carriers examined at the moment of the diagnosis of myelitis. RESULTS: The classical triad (lumbago, weakness at the lower limbs and urinary dysfunctions was documented in 11 (86.61% patients. The distribution of the clinical forms was: myeloradicular in six patients (46.15%, radicular in four (30.76% and myelitic in three (23.07%. CONCLUSION: The radicular dysfunction and their clinical associated forms were the most prominent pattern during the early phase of this disease.

  20. Sobre o método de Kato no diagnóstico da esquistossomose mansoni

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    Aparecida Marly P. Dantas

    1973-06-01

    Full Text Available Os autores fazem um estudo comparativo entre os métodos de sedimentação, MIF-C e Kato em relação à eficiência para diagnosticar ovos de helmintos, em especial os de Schistosoma mansoni. Discutem as possibilidades e limitações dos métodos assinalados e concluem pela maior eficiência do método de sedimentação.A comparative study of Kato, Hoffman - Pons - Jansr and MIF-C techniques for the diagnosis of helmintic eggs, especially S. mansoni is concerned. The authors conclude that the Hoffman - Pons - Janer is still the most adequate

  1. 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.

  2. Impact of experimental duel infections with Schistosoma mansoni and Echinoccocus granulosus on hepatic histopathology.

    Science.gov (United States)

    Elwakil, Hala S; Ali, Nehad M; Talaat, Roba M; Osman, Wesam M

    2007-12-01

    Experimental duel infection with S. mansoni and E. granulosus was induced in mice to determine their effect on serum nitric oxide (NO) level and accordingly on the sequences of histopathological lesions affecting the liver. The results showed that serum NO level was significantly increased (pduel infection with the two parasites affected serum NO level and hepatic histopathology, by ameliorative or deteriorative effects, according to duration of infection with either. PMID:18431992

  3. Immunoproteomic Analysis of the Excretory-Secretory Proteins from Spirometra Mansoni Sparganum

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    Zhong Quan Wang

    2013-09-01

    Full Text Available Background: Sparganosis is caused by the invasion of Spirometra sparganum into various tissues/organs. Subcutaneous sparganosis can be diagnosed by biopsy, while visceral/cerebral sparganosis is not easy to be diagnosed. The diagnosis de­pends largely on the detection of specific anti-sparganum antibodies. The specific­ity of the ELISA could be increased by using S. mansoni sparganum excretory–secre­tory (ES antigens, but it also had the cross-reactions with sera of patients with cysticercosis or paragonimiasis. The aim of this study was to identify early specific diagnostic antigens in S. mansoni sparganum ES proteins.Methods: The sparganum ES proteins were analyzed by two-dimensional electrophore­sis (2-DE and Western blot probed with early sera from infected mice at 14 days post-infection. The immunoreactive protein spots were characterized by MALDI-TOF/ TOF-MS.Results: A total of approximately 149 proteins spots were detected with isoelectric point (pI varying from 3 to 7.5 and molecular weight from 20 to 115 kDa and seven protein spots with molecular weight of 23-31 kDa were recognized by the infection sera. Three of seven spots were successfully identified and characterized as the same S. mansoni protein (cysteine protease, and the proteins of other 4 spots were not included in the databases.Conclusion: The cysteine protease from S. mansoni ES proteins recognized by early infection sera might be the early diagnostic antigens for sparganosis.

  4. [Developmental bilharziasis caused by Schistosoma mansoni discovered 37 years after infestation].

    Science.gov (United States)

    Chabasse, D; Bertrand, G; Leroux, J P; Gauthey, N; Hocquet, P

    1985-01-01

    The authors report a case of Mansoni Schistosomiasis whose course in always running thirty-seven years after the first and alone infestation in a fifty-six old man who come back from Madagascar in February 1948 and lives in France since this period eggs of schistosomiasis were living in a biopsy of rectal and sigmoid mucosea. Problem of adult worms longevity and clinical importance of such prolonged inapparent schistosomiasis are discussed. PMID:3936631

  5. In vitro and in vivo effects of hesperidin treatment on adult worms of Schistosoma mansoni.

    Science.gov (United States)

    Allam, G; Abuelsaad, A S A

    2014-09-01

    Hesperidin has been reported to exert a wide range of pharmacological effects, including antifungal, antiviral, antioxidant, anti-inflammatory and anticarcinogenic activities. Herein, the schistosomicidal activity of this compound was evaluated in vitro and in vivo. Using an in vitro assay, a concentration of 200 μg/ml of hesperidin resulted in the mortality of 100% adult worms of Schistosoma (S.) mansoni within 72 h and a partial tegumental alteration in 10% of worms. However, after 144 h incubation, 50 and 100 μg/ml concentrations showed 0% and 10% mortality in adult worms, respectively, without any changes to the tegument. Sublethal doses did not influence egg output nor the development of eggs deposited by pairs of adult worms. In an in vivo study, mice infected with S. mansoni and treated with 600 mg hesperidin/kg body weight showed a respective reduction of 50, 45.2, 50 and 47.5% of males, females, worm pairs and total worm burden. In addition, a respective reduction, based on the number of eggs/g tissue, of 41.5, 63.7 and 58.6% was observed in the liver, intestine and liver/intestinal tissue combined. Furthermore, S. mansoni-specific IgG level significantly increased with hesperidin treatment, whereas IgA and IgE levels were not significantly changed. IgM levels decreased in response to cercarial antigen preparation but were not altered in response to soluble worm or soluble egg antigen. As in hesperidin-treated mice, praziquantel-treated mice showed a similar pattern of specific antibody response to S. mansoni antigens. The present study represents the first report on the effects of the schistosomicidal activity of hesperidin.

  6. Parasitological characteristics of Schistosoma mansoni infection in swiss mice with underlying malnutrition

    OpenAIRE

    Simões Carla; Neves Renata Heisler; Barros Lucas de Andrade; Brito Patrícia Dias; Cravo Cristiane Oliveira; Moura Egberto Gaspar de; Machado-Silva José Roberto

    2002-01-01

    The effects of a protein-restricted diet (8% protein, 81% carbohydrate and 11% lipids) on Schistosoma mansoni infectivity, fecal egg excretion and intestinal egg distribution in Swiss (SW) mice were studied. Pregnant mice received a deficient diet from the middle of gestation until delivery. Seven-days-old mice were exposed to 50 cercariae (BH strain, Brazil). Offspring mice had a free access to the deficient diet since lactation until adulthood. The controls were fed with a commercial mice d...

  7. Schistosoma mansoni-Mediated Suppression of Allergic Airway Inflammation Requires Patency and Foxp3+ Treg Cells

    OpenAIRE

    Layland, Laura E.; Kathrin Straubinger; Manuel Ritter; Eva Loffredo-Verde; Holger Garn; Tim Sparwasser; Clarissa Prazeres da Costa

    2013-01-01

    The continual rise of asthma in industrialised countries stands in strong contrast to the situation in developing lands. According to the modified Hygiene Hypothesis, helminths play a major role in suppressing bystander immune responses to allergens, and both epidemiological and experimental studies suggest that the tropical parasitic trematode Schistosoma mansoni elicits such effects. The focus of this study was to investigate which developmental stages of schistosome infection confer suppre...

  8. Schistosoma mansoni: Tyrosinkinase-Signalwege in den Reproduktionsorganen und Aktin-Promotoranalysen im Transgenmodell

    OpenAIRE

    Beckmann, Svenja

    2008-01-01

    Der humanpathogene Parasit Schistosoma mansoni zeigt ein im Tierreich nahezu einmaliges biologisches Phänomen - die vom Männchen beeinflusste Maturation des Weibchens. Während der Paarung werden Signalkaskaden im Weibchen initiiert, die Proliferations- und Differenzierungsprozesse in den Reproduktionsorganen steuern. Um die zugrunde liegenden molekularen Prozesse besser zu verstehen, wurden in unserer Arbeitsgruppe Gene kloniert und charakterisiert, die für Signalmoleküle kodieren. Darunter ...

  9. Schistosoma mansoni and Biomphalaria snails in Lake Victoria: distribution, genetics and ecological dynamics

    OpenAIRE

    Standley, Claire J

    2011-01-01

    Intestinal schistosomiasis, caused by the trematode parasite Schistosoma mansoni, is a disease of major public health importance in the Lake Victoria region. Accurate information pertaining to the disease's distribution can greatly assist in the maintenance and realignment of existing control strategies. Rapid mapping of disease prevalence is reliant on diagnostic technologies; in the case of intestinal schistosomiasis, traditional stool-based methods are beginning to be complimented with new...

  10. Proteomic identification of IPSE/alpha-1 as a major hepatotoxin secreted by Schistosoma mansoni eggs.

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    Maha-Hamadien Abdulla

    2011-10-01

    Full Text Available BACKGROUND: Eggs deposited in the liver of the mammalian host by the blood fluke parasite, Schistosoma mansoni, normally drive a T-helper-2 (Th2-mediated granulomatous response in immune-competent mice. By contrast, in mice deprived of T-cells and incapable of producing granulomata, egg-secreted proteins (ESP induce acute hepatic injury and death. Previous work has shown that one such ESP, the T2 ribonuclease known as omega-1, is hepatotoxic in vivo in that specific antisera to omega-1 prevent hepatocyte damage. METHODOLOGY/PRINCIPAL FINDINGS: Using an in vitro culture system employing mouse primary hepatocytes and alanine transaminase (ALT activity as a marker of heptocyte injury, we demonstrated that S. mansoni eggs, egg-secreted proteins (ESP, soluble-egg antigen (SEA, and omega-1 are directly hepatotoxic and in a dose-dependent manner. Depletion of omega-1 using a monoclonal antibody abolished the toxicity of pure omega-1 and diminished the toxicity in ESP and SEA by 47 and 33%, respectively. Anion exchange chromatography of ESP yielded one predominant hepatotoxic fraction. Proteomics of that fraction identified the presence of IPSE/alpha-1 (IL-4 inducing principle from S. mansoni eggs, a known activator of basophils and inducer of Th2-type responses. Pure recombinant IPSE/alpha-1 also displayed a dose-dependent hepatotoxicity in vitro. Monoclonal antibody depletion of IPSE/alpha-1 abolished the latter's toxicity and diminished the total toxicity of ESP and SEA by 32 and 35%, respectively. Combined depletion of omega-1 and IPSE/alpha-1 diminished hepatotoxicity of ESP and SEA by 60 and 58% respectively. CONCLUSIONS: We identified IPSE/alpha-1 as a novel hepatotoxin and conclude that both IPSE/alpha-1 and omega-1 account for the majority of the hepatotoxicity secreted by S. mansoni eggs.

  11. Proteomic analysis of Schistosoma mansoni proteins released during in vitro miracidium-to-sporocyst transformation

    OpenAIRE

    Wu, Xiao-Jun; Sabat, Greg; Brown, James F.; Zhang, Mengzi; Taft, Andrew; Peterson, Nathan; Harms, Amy; YOSHINO, TIMOTHY P.

    2008-01-01

    Free-living miracidia of Schistosoma mansoni, upon penetration of the their snail intermediate host, undergo dramatic morphological and physiological changes as they transform to the parasitic sporocyst stage. During this transformation process, developing larvae release a diverse array of proteins, herein referred to as larval transformation proteins (LTPs), some of which are postulated to serve a parasite protective function. In the present study, nanoLC-tandem MS analysis was performed on ...

  12. Experimental evaluation of Candonocypris novaezelandiae(Crustacea:Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission

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    Fouad; Yousif; Sherif; Hafez; Samia; El; Bardicy; Menerva; Tadros; Hoda; Abu; Taleb

    2013-01-01

    Objective:To test Candonocypris novaezelandiae(Baird)(C.novaezelandiae),sub-class Ostracoda,obtained from the Nile,Egypt for its predatory activity on snail,Biomphalaria alexandrina(B.alexandrina),intermediate host of Schistosoma mansoni(S.mansoni)and on the free-living larval stages of this parasite(miracidia and cercariae).Methods:The predatory activity of C.novaezelandiae was determined on B.alexandrina snail(several densities of eggs,newly hatched and juveniles).This activity was also determined on S.mansoni miracidia and cercariae using different volumes of water and different numbers of larvae.C.novaezelandiae was also tested for its effect on infection of snails and on the cercarial production.Results:C.novaezelandiae was found to feed on the eggs,newly hatched and juvenile snails,but with significant reduction in the consumption in the presence of other diet like the blue green algae(Nostoc muscorum).This ostracod also showed considerable predatory activity on the free-living larval stages of S.mansoni which was affected by certain environmental factors such as volume of water,density of C.novaezelandiae and number of larvae of the parasite.Conclusions:The presence of this ostracod in the aquatic habitat led to significant reduction of snail population,infection rate of snails with schistosme miracidia as well as of cercarial production from the infected snails.This may suggest that introducing C.novaezelandiae into the habitat at schistosome riskv sites could suppress the transmission of the disease.

  13. Bayesian geostatistical prediction of the intensity of infection with Schistosoma mansoni in East Africa

    OpenAIRE

    Archie C.A. Clements; MOYEED, RANA; Brooker, Simon

    2006-01-01

    A Bayesian geostatistical model was developed to predict the intensity of infection with Schistosoma mansoni in East Africa. Epidemiological data from purposively-designed and standardized surveys were available for 31,458 schoolchildren (90% aged between 6-16 years) from 459 locations across the region and used in combination with remote sensing environmental data to identify factors associated with spatial variation in infection patterns. The geostatistical model explicitly takes into accou...

  14. 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.

  15. Reductions in genetic diversity of Schistosoma mansoni populations under chemotherapeutic pressure: the effect of sampling approach and parasite population definition.

    Science.gov (United States)

    French, Michael D; Churcher, Thomas S; Basáñez, María-Gloria; Norton, Alice J; Lwambo, Nicholas J S; Webster, Joanne P

    2013-11-01

    Detecting potential changes in genetic diversity in schistosome populations following chemotherapy with praziquantel (PZQ) is crucial if we are to fully understand the impact of such chemotherapy with respect to the potential emergence of resistance and/or other evolutionary outcomes of interventions. Doing so by implementing effective, and cost-efficient sampling protocols will help to optimise time and financial resources, particularly relevant to a disease such as schistosomiasis currently reliant on a single available drug. Here we explore the effect on measures of parasite genetic diversity of applying various field sampling approaches, both in terms of the number of (human) hosts sampled and the number of transmission stages (miracidia) sampled per host for a Schistosoma mansoni population in Tanzania pre- and post-treatment with PZQ. In addition, we explore population structuring within and between hosts by comparing the estimates of genetic diversity obtained assuming a 'component population' approach with those using an 'infrapopulation' approach. We found that increasing the number of hosts sampled, rather than the number of miracidia per host, gives more robust estimates of genetic diversity. We also found statistically significant population structuring (using Wright's F-statistics) and significant differences in the measures of genetic diversity depending on the parasite population definition. The relative advantages, disadvantages and, hence, subsequent reliability of these metrics for parasites with complex life-cycles are discussed, both for the specific epidemiological and ecological scenario under study here and for their future application to other areas and schistosome species.

  16. 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.

  17. 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.

  18. Activation-induced apoptosis in peripheral blood mononuclear cells during hepatosplenic Schistosoma mansoni infections.

    Science.gov (United States)

    Ghoneim, H M; Demian, S R; Heshmat, M G; Ismail, N S; El-Sayed, Laila H

    2008-01-01

    It is well established that programmed cell death (apoptosis) is an important regulator of host responses during infection with a variety of intra- and extra-cellular pathogens. The present work aimed at assessment of in vitro spontaneous and phytohemagglutinin (PHA)-induced apoptosis in mononuclear cells isolated from patients with hepatosplenic form of S. mansoni infections. Cell death data were correlated to the degree of lymphoproliferative responses to PHA as well as to the serum anti-schistosomal antibody titers. A markedly significant increase in PHA-induced apoptosis in lymphocytes isolated from S. mansoni-infected patients was seen when compared to the corresponding healthy controls. However, a slight difference was recorded between the two studied groups regarding the spontaneous apoptosis. This was accompanied with a significant impairment of in vitro PHA-induced lymphoproliferation of T cells from S. mansoni patients. Data of the present study supports the hypothesis that activation-induced cell death (AICD) is a potentially contributing factor in T helper (Th) cell regulation during chronic stages of schistosomiasis, which represents a critically determinant factor in the host-parasite interaction and might influence the destiny of parasitic infections either towards establishment of chronic infection or towards host death. PMID:20306689

  19. Envolvimento renal na associação salmonella-Schistosoma mansoni

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    José Roberto Lambertucci

    1987-06-01

    Full Text Available Vinte pacientes com a associação Salmonella-S. mansoni (Grupo 1 e 20 com esquistossomose mansoni hepatesplênica (Grupo 2 foram selecionados para o estudo. Submeteram-se os pacientes dos Grupos le 2 a exame clínico minucioso e a uma série de exames complementares, com destaque para as provas de função renal. Em 10 pacientes do Grupo 1 e 20 do Grupo 2, realizou-se, ainda, estudo histológico do rim à microscopia óptica, de fluorescência e eletrônica. As alterações renais foram mais freqüentes nos pacientes do Grupo 1. Após o tratamento dos pacientes do Grupo 1, com antibióticos e/ou esquistossomicidas, observou-se regressão das alterações renais sob o ponto de vista clínico, laboratorial e imunopatológico. Os autores concluem pela existência de duas nefropatias distintas: a nefropatia esquistossomótica e a encontrada em pacientes com a associação Salmonella-S. mansoni.

  20. 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

  1. 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.

  2. Efficacy of oxamniquine, praziquantel and a combination of both drugs in schistosomiasis mansoni in Brazil

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    K. Zwingenberger

    1987-10-01

    Full Text Available A randomized clinical trial was carried out to compare the efficacy of a low-dosage combination of oxamniquine (7.5 mg/kg plus praziquantel (20 mg/kg against either agent, oxamniquine (15 mg/kg or praziquantel (40 mg/kg alone, in the treatment of schistosomiasis mansoni in the Brazilian north-east. The drugs were randomly administered per os to 91 patients. Six and twelve months after treatment 89% of those admitted to the trial were reexamined by Kato-Katz method (ten slides and MIF technique (one gram of stool The achieved cure rates, as defined by absence of S. mansoni eggs in the faeces of individual patients at all points during the parasitological follow-up, were 81.8%, 81.2% and 67.6% for praziquantel, oxamniquine and the combination respectively. The reduction of eggs excretion in non cured patients six months after therapy ranged from 93.8-96.8% with praziquantel, 32.5-97% with oxamniquine and 76.9-99.5% with the combination. It is concluded that, at the used dosages, the three therapeutical regimens give similar and satisfactory results in the treatment of uncomplicated S. mansoni infection in Brazil.

  3. Activation-induced apoptosis in peripheral blood mononuclear cells during hepatosplenic Schistosoma mansoni infections.

    Science.gov (United States)

    Ghoneim, H M; Demian, S R; Heshmat, M G; Ismail, N S; El-Sayed, Laila H

    2008-01-01

    It is well established that programmed cell death (apoptosis) is an important regulator of host responses during infection with a variety of intra- and extra-cellular pathogens. The present work aimed at assessment of in vitro spontaneous and phytohemagglutinin (PHA)-induced apoptosis in mononuclear cells isolated from patients with hepatosplenic form of S. mansoni infections. Cell death data were correlated to the degree of lymphoproliferative responses to PHA as well as to the serum anti-schistosomal antibody titers. A markedly significant increase in PHA-induced apoptosis in lymphocytes isolated from S. mansoni-infected patients was seen when compared to the corresponding healthy controls. However, a slight difference was recorded between the two studied groups regarding the spontaneous apoptosis. This was accompanied with a significant impairment of in vitro PHA-induced lymphoproliferation of T cells from S. mansoni patients. Data of the present study supports the hypothesis that activation-induced cell death (AICD) is a potentially contributing factor in T helper (Th) cell regulation during chronic stages of schistosomiasis, which represents a critically determinant factor in the host-parasite interaction and might influence the destiny of parasitic infections either towards establishment of chronic infection or towards host death.

  4. Bioinformatic analysis for structure and function of TCTP from Spirometra mansoni

    Institute of Scientific and Technical Information of China (English)

    Ya-Jun Lu; Gang Lu; Da-Zhong Shi; Li-Hua Li; Sai-Feng Zhong

    2013-01-01

    Objective:To predict structure and function of translationally controlled tumor protein (TCTP) from Spirometra mansoni by bioinformatics technology, and to provide a theoretical basis for further study. Methods: Open reading frame (ORF) of EST sequence from Spirometra mansoni was obtained by ORF finder and was translated into amino acid residue by DNAclub. The structure domain was analyzed by Blast. By the method of online analysis tools: Protparam, InterProScan, protscale, SignalP-3.0, PSORTⅡ, BepiPred, TMHMM, VectorNTI Suite 9 packages and Phyre2, the structure and function of the protein were predicted and analyzed. Results:The results showed that the EST sequence was Sm TCTP with 173 amino acid residues, theoretical molecular weight was 19 872.0 Da. The protein has the closest evolutionary status with Clonorchis sinensis, Schistosoma mansoni, and Schistosoma japonicum. Then it had no signal peptide site and transmembrane domain. Secondary structure of TCTP contained twoα-helices and eightβ-strands. Conclusions:Sm TCTP was a variety of biological functions of protein that may be used as a vaccine candidate molecule and drug target.

  5. RE-EVALUATION OF SCHISTOSOMIASIS MANSONI IN MINAS GERAIS, BRAZIL. III. "NOROESTE DE MINAS" MESOREGION

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    CARVALHO Omar S.

    1998-01-01

    Full Text Available This study was conducted to assess the presence of schistosomiasis mansoni in the "Noroeste de Minas" mesoregion, an area considered non-endemic. A malacologic survey and parasitologic stool examinations were undertaken in 13 municipalities of the mesoregion. A sample of 3,283 primary school students was submitted to fecal examination by the Kato-Katz method. A total of 3,627 planorbids was collected and examined. The molluscs were identified as Biomphalaria straminea in seven municipalities (Unaí, Bonfinópolis de Minas, Paracatu, João Pinheiro, Vazante, Lagamar and Lagoa Grande and as Biomphalaria peregrina in one (Presidente Olegário. All planorbids were negative for Schistosoma mansoni. Four students were diagnosed with schistosomiasis in the municipalities of Buritis, Formoso, Paracatu and Unaí, but none of these cases was considered autochthonous. The data obtained indicate that the "Noroeste de Minas" mesoregion continues to be non-endemic for schistosomiasis mansoni, although the presence of intermediate hosts associated with parasitized individuals emphasizes the need for epidemiological surveillance of schistosomiasis in this mesoregion.

  6. Atypical properties of a conventional calcium channel β subunit from the platyhelminth Schistosoma mansoni

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    Schneider Toni

    2008-03-01

    Full Text Available Abstract Background The function of voltage-gated calcium (Cav channels greatly depends on coupling to cytoplasmic accessory β subunits, which not only promote surface expression, but also modulate gating and kinetic properties of the α1 subunit. Schistosomes, parasitic platyhelminths that cause schistosomiasis, express two β subunit subtypes: a structurally conventional β subunit and a variant β subunit with unusual functional properties. We have previously characterized the functional properties of the variant Cavβ subunit. Here, we focus on the modulatory phenotype of the conventional Cavβ subunit (SmCavβ using the human Cav2.3 channel as the substrate for SmCavβ and the whole-cell patch-clamp technique. Results The conventional Schistosoma mansoni Cavβ subunit markedly increases Cav2.3 currents, slows macroscopic inactivation and shifts steady state inactivation in the hyperpolarizing direction. However, currents produced by Cav2.3 in the presence of SmCavβ run-down to approximately 75% of their initial amplitudes within two minutes of establishing the whole-cell configuration. This suppressive effect was independent of Ca2+, but dependent on intracellular Mg2+-ATP. Additional experiments revealed that SmCavβ lends the Cav2.3/SmCavβ complex sensitivity to Na+ ions. A mutant version of the Cavβ subunit lacking the first forty-six amino acids, including a string of twenty-two acidic residues, no longer conferred sensitivity to intracellular Mg2+-ATP and Na+ ions, while continuing to show wild type modulation of current amplitude and inactivation of Cav2.3. Conclusion The data presented in this article provide insights into novel mechanisms employed by platyhelminth Cavβ subunits to modulate voltage-gated Ca2+ currents that indicate interactions between the Ca2+ channel complex and chelated forms of ATP as well as Na+ ions. These results have potentially important implications for understanding previously unknown mechanisms by

  7. Quantitative high-throughput screen identifies inhibitors of the Schistosoma mansoni redox cascade.

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    Anton Simeonov

    Full Text Available Schistosomiasis is a tropical disease associated with high morbidity and mortality, currently affecting over 200 million people worldwide. Praziquantel is the only drug used to treat the disease, and with its increased use the probability of developing drug resistance has grown significantly. The Schistosoma parasites can survive for up to decades in the human host due in part to a unique set of antioxidant enzymes that continuously degrade the reactive oxygen species produced by the host's innate immune response. Two principal components of this defense system have been recently identified in S. mansoni as thioredoxin/glutathione reductase (TGR and peroxiredoxin (Prx and as such these enzymes present attractive new targets for anti-schistosomiasis drug development. Inhibition of TGR/Prx activity was screened in a dual-enzyme format with reducing equivalents being transferred from NADPH to glutathione via a TGR-catalyzed reaction and then to hydrogen peroxide via a Prx-catalyzed step. A fully automated quantitative high-throughput (qHTS experiment was performed against a collection of 71,028 compounds tested as 7- to 15-point concentration series at 5 microL reaction volume in 1536-well plate format. In order to generate a robust data set and to minimize the effect of compound autofluorescence, apparent reaction rates derived from a kinetic read were utilized instead of end-point measurements. Actives identified from the screen, along with previously untested analogues, were subjected to confirmatory experiments using the screening assay and subsequently against the individual targets in secondary assays. Several novel active series were identified which inhibited TGR at a range of potencies, with IC(50s ranging from micromolar to the assay response limit ( approximately 25 nM. This is, to our knowledge, the first report of a large-scale HTS to identify lead compounds for a helminthic disease, and provides a paradigm that can be used to jump

  8. Imatinib treatment causes substantial transcriptional changes in adult Schistosoma mansoni in vitro exhibiting pleiotropic effects.

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    Christin Buro

    2014-06-01

    Full Text Available BACKGROUND: Schistosome parasites cause schistosomiasis, one of the most important infectious diseases worldwide. For decades Praziquantel (PZQ is the only drug widely used for controlling schistosomiasis. The absence of a vaccine and fear of PZQ resistance have motivated the search for alternatives. Studies on protein kinases (PKs demonstrated their importance for diverse physiological processes in schistosomes. Among others two Abl tyrosine kinases, SmAbl1 and SmAbl2, were identified in Schistosoma mansoni and shown to be transcribed in the gonads and the gastrodermis. SmAbl1 activity was blocked by Imatinib, a known Abl-TK inhibitor used in human cancer therapy (Gleevec/Glivec. Imatinib exhibited dramatic effects on the morphology and physiology of adult schistosomes in vitro causing the death of the parasites. METHODOLOGY/PRINCIPAL FINDINGS: Here we show modeling data supporting the targeting of SmAbl1/2 by Imatinib. A biochemical assay confirmed that SmAbl2 activity is also inhibited by Imatinib. Microarray analyses and qRT-PCR experiments were done to unravel transcriptional processes influenced by Imatinib in adult schistosomes in vitro demonstrating a wide influence on worm physiology. Surface-, muscle-, gut and gonad-associated processes were affected as evidenced by the differential transcription of e.g. the gynecophoral canal protein gene GCP, paramyosin, titin, hemoglobinase, and cathepsins. Furthermore, transcript levels of VAL-7 and egg formation-associated genes such as tyrosinase 1, p14, and fs800-like were affected as well as those of signaling genes including a ribosomal protein S6 kinase and a glutamate receptor. Finally, a comparative in silico analysis of the obtained microarray data sets and previous data analyzing the effect of a TGFβR1 inhibitor on transcription provided first evidence for an association of TGFβ and Abl kinase signaling. Among others GCP and egg formation-associated genes were identified as common

  9. Schistosoma mansoni infection prevalence and associated risk factors among schoolchildren in Demba Girara, Damot Woide District of Wolaita Zone, Southern Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Bereket Alemayehu; Zewdneh Tomass

    2015-01-01

    Objective:To establish the prevalence and associated risk factors of Schistosoma mansoni (S. mansoni) infection among schoolchildren at a village in Wolaita Zone, Sothern Ethiopia. Methods:A cross-sectional study was carried out among primary schoolchildren. A total of 384 randomly selected study subjects provided stool samples for parasitological examination by Kato-Katz and Formalin-Ether concentration techniques. Secondary parasitological data were obtained from Health Center Laboratory to see the previous history of S. mansoni infection in the area. Statistical analysis was performed using SPSS software version 16. Results:From the total children examined, 85.4%were found positive for at least one helminth infection. S. mansoni infection (81.3%) was the most prevalent and the prevalence of STH was 32%. Moderate and heavy infection intensities were only observed in S. mansoni infections. The overall heavy intensity of infection was 56.4%. Contact to Bisare stream was the most important factor for S. mansoni infection (OR 3.9) followed by herding cattle near the stream (OR 2.527). Males were twice more likely to get the infection than females (OR 1.923). Analysis of secondary parasitological data showed that S. mansoni infection was a leading helminthic infection over the past years. Conclusions:The present study found a higher intensity and prevalence of S. mansoni infection in a rural village of Wolaita Zone. Therefore, appropriate integrated control and prevention measures need to be implemented in the study area.

  10. Long-term effect of mass chemotherapy, transmission and risk factors for Schistosoma mansoni infection in very low endemic communities of Venezuela

    NARCIS (Netherlands)

    Hofstede, Stefanie N.; Tami, Adriana; van Liere, Genevieve A. F. S.; Ballen, Diana; Incani, Renzo N.

    2014-01-01

    The prevalence of Schistosoma mansoni infection in Venezuela has changed from high to low due mostly to successful control activities, including mass chemotherapy and molluscicide applications. This study examined the impact of mass chemotherapy on S. mansoni transmission and risk factors for infect

  11. Magnetic resonance imaging and ultrasound in hepatosplenic schistosomiasis mansoni Ressonância magnética e ultrassonografia na esquistossomose mansoni hepatoesplênica

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    José Roberto Lambertucci

    2004-08-01

    Full Text Available We report the findings of abdominal ultrasound and magnetic resonance imaging observed in a patient with advanced schistosomiasis mansoni. A 25-year-old man with hepatosplenic schistosomiasis and variceal bleeding confirmed by upper endoscopy was submitted to abdominal ultrasound and magnetic resonance imaging. During surgery for portal hypertension, a liver biopsy was taken and the diagnosis of Symmers' fibrosis was confirmed. magnetic resonance imaging scans gave more precise information about the gallbladder, periportal thickening and abdominal venous system than did the ultrasound.Relatamos os achados ultrassonográficos e à ressonância magnética intra-abdominais observados em um paciente com esquistossomose mansoni grave. Um homem de 25 anos de idade com esquistossomose hepatoesplênica e sangramento digestivo de varizes esofagianas, com diagnóstico confirmado pela endoscopia, foi submetido à ultrasonografia abdominal e ressonância magnética. Durante a cirurgia de hipertensão porta, um fragmento de fígado foi obtido e o exame histológico confirmou o diagnóstico de fibrose de Symmers. A ressonância magnética forneceu informações mais precisas sobre a vesícula biliar, espessamento periportal e sistema venoso abdominal do que a ultrassonografia.

  12. ULTRASTRUCTURAL CHANGES IN Schistosoma mansoni MALE WORMS AFTER in vitro INCUBATION WITH THE ESSENTIAL OIL OF Mentha x villosa Huds

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    Thiago José MATOS-ROCHA

    2016-01-01

    Full Text Available Introduction: The essential oil Mentha x villosa (MVEO has a wide range of actions, including antibacterial, antifungal, antiprotozoal and schistosomicidal actions. The present study aimed to investigate the ultrastructural changes of MVEO on the tegument of adult Schistosoma mansoni. Materials and Methods: Different concentrations of MVEO were tested on S. mansoni adult worms in vitro. Ultrastructural changes on the tegument of these adult worms were evaluated using scanning electron microscopy (SEM and transmission electron microscopy (TEM. Results: The MVEO caused the death of all worms at 500 μg mL-1 after 24 h. After 24h of 500 μg mL-1 MVEO treatment, bubble lesions were observed over the entire body of worms and they presented loss of tubercles in some regions of the ventral portion. In the evaluation by TEM, S. mansoni adult worms treated with MVEO, 500 μg mL-1, presented changes in the tegument and vacuoles in the syncytial matrix region. Glycogen granules close to the muscle fibers were visible. Conclusion: The ability of MVEO to cause extensive ultrastructural damage to S. mansoni adult worms correlates with its schistosomicidal effects and confirms earlier findings with S. mansoni.

  13. The Schistosoma mansoni phylome: using evolutionary genomics to gain insight into a parasite’s biology

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    Silva Larissa

    2012-11-01

    Full Text Available Abstract Background Schistosoma mansoni is one of the causative agents of schistosomiasis, a neglected tropical disease that affects about 237 million people worldwide. Despite recent efforts, we still lack a general understanding of the relevant host-parasite interactions, and the possible treatments are limited by the emergence of resistant strains and the absence of a vaccine. The S. mansoni genome was completely sequenced and still under continuous annotation. Nevertheless, more than 45% of the encoded proteins remain without experimental characterization or even functional prediction. To improve our knowledge regarding the biology of this parasite, we conducted a proteome-wide evolutionary analysis to provide a broad view of the S. mansoni’s proteome evolution and to improve its functional annotation. Results Using a phylogenomic approach, we reconstructed the S. mansoni phylome, which comprises the evolutionary histories of all parasite proteins and their homologs across 12 other organisms. The analysis of a total of 7,964 phylogenies allowed a deeper understanding of genomic complexity and evolutionary adaptations to a parasitic lifestyle. In particular, the identification of lineage-specific gene duplications pointed to the diversification of several protein families that are relevant for host-parasite interaction, including proteases, tetraspanins, fucosyltransferases, venom allergen-like proteins, and tegumental-allergen-like proteins. In addition to the evolutionary knowledge, the phylome data enabled us to automatically re-annotate 3,451 proteins through a phylogenetic-based approach rather than solely sequence similarity searches. To allow further exploitation of this valuable data, all information has been made available at PhylomeDB (http://www.phylomedb.org. Conclusions In this study, we used an evolutionary approach to assess S. mansoni parasite biology, improve genome/proteome functional annotation, and provide insights into

  14. Morbidade da esquistossomose mansoni no Brasil: III Estudo evolutivo em uma área endêmica no período de dez anos Morbidity of schistosomiasis mansoni in Brazil. III.Evolutive study in an endemic area in a period of 10 years

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    José Rodrigues Coura

    1984-12-01

    conta própria.Four cross sectional studies on morbidity of schistosomiasis mansoni were carried out respectively in 1973, 1974, 1979 and 1983 in the Village of Capitão Andrade, District of Itanhomi, State of Minas Gerais, Brazil, through clinical and fecal examination of the population. In addition a comparison was made of the dinamic and infection rate of the snails and the man-water contact between 1973-1974. The present study compares the prevalence of the human infection by S. mansoni and the evolutive pattern of the disease in the area from 1973 to 1983. besides 190 persons infected with S. mansoni and 134 non-infected, were followed-up during this period. The infection rate was 60.8% among 1,234 persons examined in 1973,, decreasing to 36.2% of the 1,269 examined in 1983. However, the intense migration of the population in the area and the specific treatment of 7% of person by their own decision may be partially responsible for this reduction. Although there was a decrease of more than 50% in the mean egg output of S. mansoni, there was no change in the morbility of the disease and in the proportion of the different clinical forms. The incidence of S. mansoni infection among 134 persons followed-up during the ten years was 40.3% (annual average of 4%, with 61.9% in males. The incidence of the clinical forms was 51.8% for type I (intestinal form, 38.9% for type II (hepatointestinal and 9.3% for type III (hepatoesplenic. The clinical evolutive pattern of 190 patients followed-up during the mentioned period showed that 75.3% had no change, 12.1% deteriored and 12,6% improved. two thirds of those which improved (8.4% had receveid specific treatment.

  15. Genetic epidemiology of human schistosomiasis in Brazil.

    Science.gov (United States)

    Bethony, Jeffrey M; Quinnell, Rupert J

    2008-01-01

    Human schistosomiasis presents the classic, complex disease phenotype, with marked variation in the intensity of infection, the immune response to infection, and the development of schistosome-related pathology. Determining the role of host genetics in schistosomiasis is complicated by the numerous parasite and environmental factors involved in transmission. However, as a result of the increased availability of sequence data, novel statistical methods, and new methods of study design, the last decade has seen significant advances in identifying the role of host genetics in schistosome infection around the world. Many of these advances have taken place in Brazil. Epidemiological studies in Brazil have shown that the intensity of infection (worm burden) is a heritable phenotype (41%). Human genome scans have identified a locus responsible for controlling Schistosoma mansoni infection intensity on chromosome 5q31-q33. There is also evidence for genetic control of pathology due to S. mansoni, with linkage reported to a region containing the gene for the interferon-gamma receptor 1 subunit. Numerous association studies have also provided evidence for major histocompatibility complex control of pathology in schistosomiasis. Recent candidate gene studies suggest a role of other immune response genes in controlling helminth infection and pathology. We chronicle the many advances made in understanding the role of host genetics in S. mansoni infection that have taken place in Brazil by phenotype studied: infection intensity, immune response, and disease development. Results from Brazilian studies are compared with studies of S. mansoni and other schistosome species elsewhere in the world. PMID:18207118

  16. Systematic Review and Meta-analysis of the Impact of Chemical-Based Mollusciciding for Control of Schistosoma mansoni and S. haematobium Transmission.

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    Charles H King

    2015-12-01

    Full Text Available Programs for schistosomiasis control are advancing worldwide, with many benefits noted in terms of disease reduction. Yet risk of reinfection and recurrent disease remain, even in areas with high treatment coverage. In the search for means to better prevent new Schistosoma infections, attention has returned to an older strategy for transmission control, i.e., chemical mollusciciding, to suppress intermediate host snail species responsible for S. mansoni and S. haematobium transmission. The objective of this systematic review and meta-analysis was to summarize prior experience in molluscicide-based control of Bulinus and Biomphalaria spp. snails, and estimate its impact on local human Schistosoma infection.The review was registered at inception with PROSPERO (CRD42013006869. Studies were identified by online database searches and hand searches of private archives. Eligible studies included published or unpublished mollusciciding field trials performed before January 2014 involving host snails for S. mansoni or S. haematobium, with a primary focus on the use of niclosamide. Among 63 included papers, there was large variability in terms of molluscicide dosing, and treatment intervals varied from 3-52 weeks depending on location, water source, and type of application. Among 35 studies reporting on prevalence, random effects meta-analysis indicated that, on average, odds of infection were reduced 77% (OR 0.23, CI95% 0.17, 0.31 during the course of mollusciciding, with increased impact if combined with drug therapy, and progressively greater impact over time. In 17 studies reporting local incidence, risk of new infection was reduced 64% (RR 0.36 CI95% 0.25, 0.5, but additional drug treatment did not appear to influence incidence effects.While there are hurdles to implementing molluscicide control, its impact on local transmission is typically strong, albeit incomplete. Based on past experience, regular focal mollusciciding is likely to contribute

  17. Structure-Bioactivity Relationship for Benzimidazole Thiophene Inhibitors of Polo-Like Kinase 1 (PLK1, a Potential Drug Target in Schistosoma mansoni.

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    Thavy Long

    2016-01-01

    Full Text Available Schistosoma flatworm parasites cause schistosomiasis, a chronic and debilitating disease of poverty in developing countries. Praziquantel is employed for treatment and disease control. However, its efficacy spectrum is incomplete (less active or inactive against immature stages of the parasite and there is a concern of drug resistance. Thus, there is a need to identify new drugs and drug targets.We show that RNA interference (RNAi of the Schistosoma mansoni ortholog of human polo-like kinase (huPLK1 elicits a deleterious phenotypic alteration in post-infective larvae (schistosomula or somules. Phenotypic screening and analysis of schistosomula and adult S. mansoni with small molecule inhibitors of huPLK1 identified a number of potent anti-schistosomals. Among these was a GlaxoSmithKline (GSK benzimidazole thiophene inhibitor that has completed Phase I clinical trials for treatment of solid tumor malignancies. We then obtained GSKs Published Kinase Inhibitor Sets (PKIS 1 and 2, and phenotypically screened an expanded series of 38 benzimidazole thiophene PLK1 inhibitors. Computational analysis of controls and PLK1 inhibitor-treated populations of somules demonstrated a distinctive phenotype distribution. Using principal component analysis (PCA, the phenotypes exhibited by these populations were mapped, visualized and analyzed through projection to a low-dimensional space. The phenotype distribution was found to have a distinct shape and topology, which could be elicited using cluster analysis. A structure-activity relationship (SAR was identified for the benzimidazole thiophenes that held for both somules and adult parasites. The most potent inhibitors produced marked phenotypic alterations at 1-2 μM within 1 h. Among these were compounds previously characterized as potent inhibitors of huPLK1 in cell assays.The reverse genetic and chemical SAR data support a continued investigation of SmPLK1 as a possible drug target and/or the prosecution of

  18. Transmission of Schistosoma mansoni under experimental conditions using the bovine - Biomphalaria glabrata - bovine model Transmissão do Schistosoma mansoni em condições experimentais, usando o modelo bovino - Biomphalaria glabrata - bovino

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    Celina M. Modena

    1993-02-01

    Full Text Available Three calves experimentally infected with Schistosoma mansoni, and passing viable eggs in feces, as well as 5 normal calves (coming from a non-endemic area for schistosomiasis kept as controls, were maintained in an enclosure (850 m² in area. In this enclosure, a tank with water received 500 laboratory reared Biomphalaria glabrata. All the control calves were infected for a period ranging from 79 to 202 days after the beginning of the experiment, and afterwards presented viable S. mansoni eggs in feces. The mean worm recovery was 555. The snail population increased throughout the experimental period, showing a high number of B. glabrata infected with S. mansoni (42% on average. According to the present study, bovine has been suggested as having potentially a role in the maintenance of the life cycle of S. mansoniTrês bezerros, experimentalmente infectados com Schistosoma mansoni e passando ovos viáveis nas fezes, bem como 5 bezerros normais, oriundos de área não endêmica para esquistossomose e usados como controles, foram mantidos em uma área fechada de 850 m². Nesta área, foram colocados em um tanque com água 500 caramujos Biomphalaria glabrata criados em laboratório. Todos os bezerros controles foram infectados por um período de 79 a 202 dias após o começo do experimento e, mais tarde, apresentaram ovos viáveis de S. mansoni nas fezes. A recuperação média de vermes foi de 538. A população de moluscos aumentou durante o período experimental, mostrando um número significativo de B. glabrata infectados com S. mansoni (42% em média. De acordo com o resultado do presente trabalho, que foi conduzido em condições experimentais, foi sugerido que bovinos tem, potencialmente, um papel na manutenção do ciclo vital do S. mansoni

  19. Effect of skin colour and selected physical characteristics on Schistosoma mansoni dependent morbidity Efeito da cor da pele e certas características físicas na morbidade dependente de Schistosoma mansoni

    OpenAIRE

    C. B. Cançado; J. O. A. Firmo; Fernandes, S C; Rocha, R. S.; M. F. F. Lima e Costa

    1995-01-01

    The effect of the colour group on the morbidity due to Schistosoma mansoni was examined in two endemic areas situated in the State of Minas Gerais, Brazil. Of the 2773 eligible inhabitants, 1971 (71.1%) participated in the study: 545 (27.6%) were classified as white, 719 (36.5%) as intermediate and 707 (35.9%) as black. For each colour group, signs and symptoms of individuals who eliminated S.mansoni eggs (cases) were compared to those who did not present eggs in the faeces (controls). The od...

  20. Bayesian risk maps for Schistosoma mansoni and hookworm mono-infections in a setting where both parasites co-exist

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    Giovanna Raso

    2007-11-01

    Full Text Available There is growing interest in the use of Bayesian geostatistical models for predicting the spatial distribution of parasitic infections, including hookworm, Schistosoma mansoni and co-infections with both parasites. The aim of this study was to predict the spatial distribution of mono-infections with either hookworm or S. mansoni in a setting where both parasites co-exist. School-based cross-sectional parasitological and questionnaire surveys were carried out in 57 rural schools in the Man region, western Côte d’Ivoire. A single stool specimen was obtained from each schoolchild attending grades 3-5. Stool specimens were processed by the Kato-Katz technique and an ether concentration method and examined for the presence of hookworm and S. mansoni eggs. The combined results from the two diagnostic approaches were considered for the infection status of each child. Demographic data (i.e. age and sex were obtained from readily available school registries. Each child’s socio-economic status was estimated, using the questionnaire data following a household-based asset approach. Environmental data were extracted from satellite imagery. The different data sources were incorporated into a geographical information system. Finally, a Bayesian spatial multinomial regression model was constructed and the spatial patterns of S. mansoni and hookworm mono-infections were investigated using Bayesian kriging. Our approach facilitated the production of smooth risk maps for hookworm and S. mansoni mono-infections that can be utilized for targeting control interventions. We argue that in settings where S. mansoni and hookworm co-exist and control efforts are under way, there is a need for both mono- and co-infection risk maps to enhance the cost-effectiveness of control programmes.

  1. Green tea (Camellia sinesis) ameliorates female Schistosoma mansoni-induced changes in the liver of Balb/C mice.

    Science.gov (United States)

    Bin Dajem, Saad M; Shati, Ali A; Adly, Mohamed A; Ahmed, Osama M; Ibrahim, Essam H; Mostafa, Osama M S

    2011-10-01

    This study was designed to assess the effect of green tea, an aqueous extract of Camellia sinensis, on the oxidative stress, antioxidant defense system and liver pathology of Schistosoma mansoni-infected mice. Green tea at concentration of 3% (w/v) was given orally to treated mice as sole source of drinking water from the end of the 4th week to the end of 10th week post-infection; untreated mice were allowed to drink normal water. The data of the studied S. mansoni-infected mice exhibited a suppression of hepatic total antioxidant capacity, superoxide dismutase (SOD), catalase (CAT) activity and glutathione content. The liver lipid peroxidation was deleteriously elevated in S. mansoni-infected mice. The hepatic total protein content, AST and ALT activities were profoundly decreased in the S. mansoni-infected mice. Most hepatocytes were damaged and showed abnormal microscopic appearance with aggressive necrosis. Both total protein and glycogen levels have been greatly reduced as indicated by histochemical examination. The treatment of S. mansoni-infected mice with green tea succeeded to suppress oxidative stress by decreasing the lipid peroxides but failed to significantly enhance the antioxidant defense system and deteriorated changes owing to liver damage and necrosis. In consistence with biochemical data, histopathological and histochemical data indicated that treatment of S. mansoni-infected mice with green tea could ameliorate hepatocytes thus reduce cellular necrosis and partially restore both total protein and glycogen levels. Thus, the study concluded that the green tea suppresses the oxidative stress through its constituent with free radicals scavenging properties rather than through the endogenous antioxidant defense system.

  2. 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.

  3. 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.

  4. 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

  5. Sintomatologia intestinal na fase crônica da esquistossomose mansoni

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    Eleonora L. Peixinho

    1986-03-01

    Full Text Available Com o objetivo de investigar os sintomas intestinais na fase crônica da esquistossomose mansoni, estudamos 102 indivíduos na faixa etária de nove a dezenove anos, dos 144previamente selecionados entre os moradores autóctones dos distritos de Lagoa Redonda e Menezes, portadores de Schistosoma mansoni. Todos foram submetidos a uma anamnese segmentar com a finalidade de detectara presença de cinco sintomas intestinais: dor abdominal, diarréia, muco e rajas de sangue nas fezes e enterorragia. Metade dos pacientes foi medicada com mebendazole e posteriormente com oxamniquine, constituindo-se no grupo caso, enquanto a outra metade, tratada apenas com mebendazole, constituiu-se no grupo controle. Os resultados mostram que a esquistossomose é provavelmente a responsável pelas queixas de muco e/ou rajas de sangue nas fezes, ocorrendo uma redução dessas queixas, estatisticamente significante, após a terapêutica específica.A total of 102 autochthonous patients from the districts of Lagoa Redonda and Menezes (Sapeaçu, Bahia, with ages rangingfrom nine to 19years, were evaluated for intestinal symptoms related to the chronic phase of Schistosomiasis mansoni, with emphasis on the following complaints: abdominal pain, diarrhea, mucus and blood in the stools. One half of the sample (case group was treated with mebendazole followed by oxamniquine; the otherhalf (control group received only mebendazole. The results showed that schistosomiasis is probably responsible for the appearance of mucus and/or blood in the stools, since a statistically significant reduction of such manifestations was achieved with specific treatment.

  6. Molecular approach for detecting early prepatent Schistosoma mansoni infection in Biomphalaria alexandrina snail host.

    Science.gov (United States)

    Farghaly, Adel; Saleh, Ayman A; Mahdy, Soad; Abd El-Khalik, Dalia; Abd El-Aal, Naglaa F; Abdel-Rahman, Sara A; Salama, Marwa A

    2016-09-01

    The present study aimed to evaluate a polymerase chain reaction (PCR) assay used for detection of Schistosoma mansoni infection in Biomphalaria alexandrina snails in early prepatent period and to compare between it and the ordinary detection methods (shedding and crushing). Biomphalaria alexandrina snails are best known for their role as intermediate hosts of S. mansoni. DNA was extracted from infected snails in addition to non-infected "negative control" (to optimized the efficiency of PCR reaction) and subjected to PCR using primers specific to a partial sequence of S. mansoni fructose-1,6-bus phosphate aldolase (SMALDO). SMALDO gene was detected in the infected laboratory snails with 70, 85, and 100 % positivity at the 1st, 3rd, and 7th day of infection, respectively. In contrast, the ordinary method was not sensitive enough in detection of early prepatent infection even after 7 days of infection which showed only 25 % positivity. By comparing the sensitivity of the three methods, it was found that the average sensitivity of shedding method compared to PCR was 23.8 % and the average sensitivity of crushing method compared to PCR was 46.4 % while the sensitivity of PCR was 100 %. We conclude that PCR is superior to the conventional methods and can detect positive cases that were negative when examined by shedding or crushing methods. This can help in detection of the areas and times of high transmission which in turn will be very beneficial in planning of the exact timing of the proper control strategy.

  7. Diagnostic and prognostic value of cell free circulating Schistosoma mansoni DNA: an experimental study.

    Science.gov (United States)

    Eraky, Maysa Ahmad; Aly, Nagwa Shaban Mohamed

    2016-09-01

    Searching for a more sensitive and accurate marker for schistosomiasis diagnosis and treatment follow up is a potential necessity. Hereby, we evaluated usefulness of circulating free DNA as a marker for schistosomiasis diagnosis, assessing drug efficacy and monitoring the control interventions impact using SYBR green real-time PCR. A batch of mice were infected by 90 ± 10 Schistosoma mansoni cercariae. Starting from the 2nd day post infection (p.i.), groups of 2 or 3 mice were sacrificed every 3 days until 30 days p.i. The remaining animals were treated by a single dose of 400 mg/kg mefloquine and sacrificed in group at 5, 10, 21 days post treatment (35, 40, 51 days p.i.). Using SYBR green real time qPCR, pooled sera DNA were extracted and amplified. The results showed that, circulating free S. mansoni DNA was detected from the 2nd day post infection (p.i.) onwards with gradual decrease in the cycle threshold value Ct which indicates the gradual elevation of the DNA level (Log quantity was 2.6-3.1 IU/ml), As the infection progressed, DNA quantity was increased(Log quantity was 6.29 IU/ml). Initial increase of circulating free DNA was observed 10 days post treatment (40 days p.i.) (Log quantity was 7.38 IU/ml). That was followed by a progressive decrease in DNA level by the end of 21st day, post treatment (51 p.i.) (Log quantity 4.35 IU/ml). In conclusion, circulating free S. mansoni DNA is a reliable marker in the diagnosis of schistosomiasis and for assessing drug efficacy and monitoring the impact of control interventions. PMID:27605830

  8. Soil transmitted helminths and schistosoma mansoni infections among school children in zarima town, northwest Ethiopia

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    Birhan Wubet

    2011-07-01

    Full Text Available Abstract Background In Ethiopia, because of low quality drinking water supply and latrine coverage, helminths infections are the second most predominant causes of outpatient morbidity. Indeed, there is a scarcity of information on the prevalence of soil transmitted helminths and Schistosomiasis in Ethiopia, special in study area. Therefore, the aim of this study was to determine the prevalence and associated risk factors of soil transmitted helminths and intestinal Schistosomiasis. Methods Cross-sectional study was conducted among 319 school children of Zarima town from April 1 to May 25, 2009. A pre-tested structured questionnaire was used to collect socio-demographic data and possible risk factors exposure. Early morning stool samples were collected and a Kato Katz semi concentration technique was used to examine and count parasitic load by compound light microscope. Data entry and analysis was done using SPSS-15 version and p-value Results Out of 319 study subjects, 263 (82.4% of the study participants infected with one or more parasites. From soil transmitted helminths, Ascaris lumbricoides was the predominant isolate (22% followed by Hookworms (19% and Trichuris trichiura (2.5%. Schistosoma mansoni was also isolated in 37.9% of the study participants. Hookworm and S. mansoni infections showed statistically significant associations with shoe wearing and swimming habit of school children, respectively. Conclusion Prevalence of soil transmitted helminths (STH and S.mansoni was high and the diseases were still major health problem in the study area which alerts public health intervention as soon as possible.

  9. Potency of Allium sativum and Allium cepa Oils against Schistosoma mansoni Infection in Mice

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    Nadia S. Metwally

    2006-06-01

    Full Text Available Introduction: It has been reported that garlic (Allium sativum and onion (Allium cepa are used all over the world in different diseases, such as infections, injuries, gastrointestinal dysfunctions and cardiovascular diseases. Therefore, our aim in this work was to study the ability of garlic and onion oils to offset the infectivity as well as the metabolic disturbances induced by Schistosoma mansoni parasitism. Methods: The two current drugs were given in a dosage of 5ml / kg body weight/ day. Three aspects of drug action were investigated, the effect on S. mansoni infection, the effect on liver functions, and on liver metabolism. The parasitological investigation included worm burden and ova count. Results: Serum biochemical analysis of infected mice revealed a significant increase in the levels of aspartate aminotransferase (AST, alanine aminotransferase (ALT , ­ glutamyltransferase (GGT , alkaline phosphatase ( ALP, acid phosphatase (AP, while a decrease in glucose, total lipids total cholesterol, high - and low- density lipoproteins cholesterol (HDL and LDL, triglycerides, total proteins and albumin was observed. Liver tissue analysis of infected animals showed a marked increase in L- hydroxyproline (HP concentration and xanthine oxidase (XO activity accompanied with a reduction in total adenosinetriphosphatase (ATPase and phosphofructokinase (PFK enzymatic activities. Treatment with either garlic or onion oils greatly normalized liver function enzymes and variably improved the other parameters with a noticeable reduction in worm burden and ova count. Conclusions: It could be concluded that garlic or onion may play a role against the metabolic disturbances caused by S. mansoni infection, owing to an effect which may be induced by improving the immunological host system and their antioxidant activities

  10. Developmental expression analysis and immunolocalization of a biogenic amine receptor in Schistosoma mansoni

    Science.gov (United States)

    El-Shehabi, Fouad; Vermeire, Jon J.; Yoshino, Timothy P.; Ribeiro, Paula

    2013-01-01

    A Schistosoma mansoni G-protein coupled receptor (SmGPCR) was previously cloned and shown to be activated by the biogenic amine, histamine. Here we report a first investigation of the receptor’s subunit organization, tissue distribution and expression levels in different stages of the parasite. A polyclonal antibody was produced in rabbits against the recombinant third intracellular loop (il3) of SmGPCR. Western blot studies of the native receptor and recombinant protein expressed in HEK293 cells showed that SmGPCR exists both as a monomer (65 kDa) and an apparent dimer of ≈130 kDa These species were verified by immunoprecipitation of SmGPCR from S. mansoni extracts, using antibody that was covalently attached to agarose beads. Further investigation determined that the SmGPCR dimer was resistant to treatment with various detergents, 4 M urea and 0.1 M DTT but could be made to dissociate at acidic pH, suggesting the dimer is non-covalent in nature. Confocal immunofluorescence studies revealed significant SmGPCR immunoreactivity in sporocysts, schistosomula and adult worms but not miracidia. SmGPCR was found to be most widely expressed in the schistosomula, particularly the tegument, the subtegumental musculature and the acetabulum. In the adult stage we detected SmGPCR immunofluorescence mainly in the tubercles of male worms and, to a lesser extent, the body wall musculature. Localization in sporocysts was mainly confined to the tegument and cells within parenchymal matrices. A realtime quantitative reverse-transcription PCR analysis revealed that SmGPCR is upregulated at the mRNA level in the parasitic stages compared to the free-living miracidium and cercariae, and it is particularly elevated during early sporocyst and schistosomula development. The results identify SmGPCR as an important parasite receptor with potential functions in muscle and the tegument of S. mansoni. PMID:19545530

  11. Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study.

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    Maha M Eissa

    Full Text Available Miltefosine (MFS is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD. This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%, good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs

  12. Molecular approach for detecting early prepatent Schistosoma mansoni infection in Biomphalaria alexandrina snail host.

    Science.gov (United States)

    Farghaly, Adel; Saleh, Ayman A; Mahdy, Soad; Abd El-Khalik, Dalia; Abd El-Aal, Naglaa F; Abdel-Rahman, Sara A; Salama, Marwa A

    2016-09-01

    The present study aimed to evaluate a polymerase chain reaction (PCR) assay used for detection of Schistosoma mansoni infection in Biomphalaria alexandrina snails in early prepatent period and to compare between it and the ordinary detection methods (shedding and crushing). Biomphalaria alexandrina snails are best known for their role as intermediate hosts of S. mansoni. DNA was extracted from infected snails in addition to non-infected "negative control" (to optimized the efficiency of PCR reaction) and subjected to PCR using primers specific to a partial sequence of S. mansoni fructose-1,6-bus phosphate aldolase (SMALDO). SMALDO gene was detected in the infected laboratory snails with 70, 85, and 100 % positivity at the 1st, 3rd, and 7th day of infection, respectively. In contrast, the ordinary method was not sensitive enough in detection of early prepatent infection even after 7 days of infection which showed only 25 % positivity. By comparing the sensitivity of the three methods, it was found that the average sensitivity of shedding method compared to PCR was 23.8 % and the average sensitivity of crushing method compared to PCR was 46.4 % while the sensitivity of PCR was 100 %. We conclude that PCR is superior to the conventional methods and can detect positive cases that were negative when examined by shedding or crushing methods. This can help in detection of the areas and times of high transmission which in turn will be very beneficial in planning of the exact timing of the proper control strategy. PMID:27605788

  13. The Role of Efflux Pumps in Schistosoma mansoni Praziquantel Resistant Phenotype

    Science.gov (United States)

    Armada, Ana; Belo, Silvana; Carrilho, Emanuel; Viveiros, Miguel; Afonso, Ana

    2015-01-01

    Background Schistosomiasis is a neglected disease caused by a trematode of the genus Schistosoma that is second only to malaria in public health significance in Africa, South America, and Asia. Praziquantel (PZQ) is the drug of choice to treat this disease due to its high cure rates and no significant side effects. However, in the last years increasingly cases of tolerance to PZQ have been reported, which has caused growing concerns regarding the emergency of resistance to this drug. Methodology/Principal Findings Here we describe the selection of a parasitic strain that has a stable resistance phenotype to PZQ. It has been reported that drug resistance in helminths might involve efflux pumps such as members of ATP-binding cassette transport proteins, including P-glycoprotein and multidrug resistance-associated protein families. Here we evaluate the role of efflux pumps in Schistosoma mansoni resistance to PZQ, by comparing the efflux pumps activity in susceptible and resistant strains. The evaluation of the efflux activity was performed by an ethidium bromide accumulation assay in presence and absence of Verapamil. The role of efflux pumps in resistance to PZQ was further investigated comparing the response of susceptible and resistant parasites in the absence and presence of different doses of Verapamil, in an ex vivo assay, and these results were further reinforced through the comparison of the expression levels of SmMDR2 RNA by RT-PCR. Conclusions/Significance This work strongly suggests the involvement of Pgp-like transporters SMDR2 in Praziquantel drug resistance in S. mansoni. Low doses of Verapamil successfully reverted drug resistance. Our results might give an indication that a combination therapy with PZQ and natural or synthetic Pgp modulators can be an effective strategy for the treatment of confirmed cases of resistance to PZQ in S. mansoni. PMID:26445012

  14. Thyroid hormone receptor orthologues from invertebrate species with emphasis on Schistosoma mansoni

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    Niles Edward G

    2007-08-01

    Full Text Available Abstract Background: Thyroid hormone receptors (TRs function as molecular switches in response to thyroid hormone to regulate gene transcription. TRs were previously believed to be present only in chordates. Results: We isolated two TR genes from the Schistosoma mansoni and identified TR orthologues from other invertebrates: the platyhelminths, S. japonium and Schmidtea mediterranea, the mollusc, Lottia gigantean and the arthropod Daphnia pulex. Phylogenetic analysis of the DNA binding domain and/or ligand binding domain shows that invertebrate and vertebrate TRs cluster together, TRs from the vertebrates and from the jawless vertebrate (lamprey clustered within separate subgroups, Platyhelminth TRs cluster outside of the vertebrate TR subgroups and that the schistosome TRs and S. mediterranea TRs clustered within separate subgroups. Alignment of the C-terminus of the A/B domain revealed a conserved TR-specific motif, termed TR 'N-terminus signature sequence', with a consensus sequence of (G/PYIPSY(M/LXXXGPE(D/EX. Heterodimer formation between S. mansoni TRs and SmRXR1 suggests that the invertebrate TR protein gained the ability to form a heterodimer with RXR. ESMA analysis showed that SmTRα could bind to a conserved DNA core motif as a monomer or homodimer. Conclusion: Vertebrate TR genes originated from a common ancestor of the Bilateria. TR genes underwent duplication independently in the Protostomia and Deuterostomia. The duplication of TRs in deuterostomes occurred after the split of jawless and jawed vertebrates. In protostomes, TR genes underwent duplication in Platyhelminths, occurring independently in trematode and turbellarian lineages. Using S. mansoni TRs as an example, invertebrate TRs exhibited the ability to form a dimer with RXR prior to the emergence of the vertebrate TRs and were able to bind to vertebrate TR core DNA elements as a monomer or homodimer.

  15. Kinetika tvorbe protutijela u teladi imunizirane glutation-S transferazom metilja Schistosoma mansoni.

    OpenAIRE

    Aradaib, Imadeldin; Omer, Rihab; Majid, Ali

    2003-01-01

    Šestero teladi bilo je imunizirano antigenom pripravljenim od glutation-S-transferaze (GST) metilja Schistosoma mansoni, koji je bio proizveden u bakteriji E. coli (GST-coli) ili kvascu (GST-kvasac). Kontrolnih šestero teladi dobilo je ekstrakt bakterije E. coli ili kvasca. Dva pokusno invadirana teleta držana su kao izvor invazije te za dobivanje antiseruma za metilj Schistosoma bovis. Kinetika tvorbe protutijela u cijepljene teladi bila je praćena postupkom Western blot i imunoenzimnim test...

  16. Schistosoma mansoni in a low-prevalence area in Brazil: the importance of additional methods for the diagnosis of hard-to-detect individual carriers by low-cost immunological assays

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    Rafaella Fortini Queiroz Grenfell

    2013-05-01

    Full Text Available Schistosomiasis diagnosis is based on the detection of eggs in the faeces, which is laborious and lacks sensitivity, especially for patients with a low parasite burden. Immunological assays for specific antibody detection are available, but they usually demonstrate low sensitivity and/or specificity. In this study, two simple immunological assays were evaluated for the detection of soluble Schistosoma mansoni adult worm preparation (SWAP and egg-specific IgGs. These studies have not yet been evaluated for patients with low parasite burdens. Residents of an endemic area in Brazil donated sera and faecal samples for our study. The patients were initially diagnosed by a rigorous Kato-Katz analysis of 18 thick smears from four different stool samples. The ELISA-SWAP was successful for human diagnosis with 90% sensitivity and specificity, confirming the Kato-Katz diagnosis with nearly perfect agreement, as seen by the Kappa index (0.85. Although the ELISA-soluble S. mansoni egg antigen was 85% sensitive, it exhibited low specificity (80%; Kappa index: 0.75 and was more susceptible to cross-reactivity. We believe that immunological assays should be used in conjunction with Kato-Katz analysis as a supplementary tool for the diagnosis of schistosomiasis for patients with low infection burdens, which are usually hard to detect.

  17. Involvement of IL-18 in the expansion of unique hepatic T cells with unconventional cytokine profiles during Schistosoma mansoni infection.

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    Keishi Adachi

    Full Text Available Infection with schistosomes invokes severe fibrotic granulomatous responses in the liver of the host. Schistosoma mansoni infection induces dramatic fluctuations in Th1 or Th2 cytokine responses systemically; Th1 reactions are provoked in the early phase, whilst Th2 responses become dominant after oviposition begins. In the liver, various unique immune cells distinct from those of conventional immune competent organs or tissues exist, resulting in a unique immunological environment. Recently, we demonstrated that S. mansoni infection induces unique CD4+ T cell populations exhibiting unconventional cytokine profiles in the liver of mice during the period between Th1- and Th2-phases, which we term the transition phase. They produce both IFN-γ and IL-4 or both IFN-γ and IL-13 simultaneously. Moreover, T cells secreting triple cytokines IFN-γ, IL-13 and IL-4 were also induced. We term these cells Multiple Cytokine Producing Hepatic T cells (MCPHT cells. During the transition phase, when MCPHT cells increase, IL-18 secretion was up-regulated in the liver and sera. In S. mansoni-infected IL-18-deficient mice, expansion of MCPHT cells was curtailed. Thus our data suggest that IL-18 produced during S. mansoni infection play a role in the expansion of MCPHT cells.

  18. 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 b...

  19. Efficacy of low-dose myrrh protocols in the treatment of experimental schistosomiasis mansoni: hepatic improvement without parasitologic cure

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    Rashad Abdul-Ghani

    2010-11-01

    Full Text Available Rashad Abdul-Ghani1, Naguiba Loutfy2, Manal Sheta3, Azza Hassan21Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Yemen; 2Tropical Health Department, High Institute of Public Health, 3Department of Pathology, Medical Research Institute, Alexandria University, Alexandria, EgyptAbstract: There is a new trend of “back to nature” in searching for antischistosomal drugs, particularly after the concerns raised about the possible emergence of schistosome isolates resistant/tolerant to praziquantel as well as for their relative safety and fewer side effects. Many plant derivatives have been investigated for efficacy against the Egyptian strain of Schistosoma mansoni, but much attention has been paid to myrrh extract, which is a purified sap obtained from Commiphora molmol. This extract has been produced and marketed in Egypt as a pharmaceutical preparation, but with a great discrepancy in its antischistosomal activity in both experimental and clinical studies. Most previous experimental studies used myrrh in the dosing protocol of 500 mg/kg/day for five days. In the present study, we investigated the therapeutic efficacy of three low-dose myrrh protocols against experimental schistosomiasis mansoni. All these protocols showed no significant efficacy in reducing parasite burdens and tissue egg loads or in changing oogram patterns. Nevertheless, there was an amelioration of hepatic lesions, with reductions in mean counts of hepatic granulomas as well as marked healing of these granulomas.Keywords: Schistosoma mansoni, schistosomiasis mansoni, myrrh, Commiphora molmol, antischistosomal chemotherapy

  20. Digenetic larvae in Schistosome snails from El Fayoum, Egypt with detection of Schistosoma mansoni in the snail by PCR.

    Science.gov (United States)

    Aboelhadid, Shawky M; Thabet, Marwa; El-Basel, Dayhoum; Taha, Ragaa

    2016-09-01

    The present study aims to detect the digenetic larvae infections in Bulinus truncatus and Biomphalaria alexandrina snails and also PCR detection of Schistosoma mansoni infection. The snails were collected from different branches of Yousef canal and their derivatives in El Fayoum Governorate. The snails were investigated for infection through induction of cercarial shedding by exposure to light and crushing of the snails. The shed cercariae were S. mansoni, Pharyngeate longifurcate type I and Pharyngeate longifurcate type II from B. alexandrina, while that found in B. truncatus were Schitosoma haematobium and Xiphidiocercaria species cercariae. The seasonal prevalence of infection was discussed. Polymerase chain reaction was used for the detection of S. mansoni in the DNA from field collected infected and non infected snails. The results of PCR showed that the pool of B. alexandrina snails which shed S. mansoni cercariae in the laboratory, gave positive reaction in the samples. Pooled samples of field collected B. alexandrina that showed negative microscopic shedding of cercariae gave negative and positive PCR in a consecutive manner. Accordingly, a latent infection in the snail (negative microscopic) could be detected by using PCR. PMID:27605774

  1. A cyclohexanecarboxamide derivative with inhibitory effects on Schistosoma mansoni cercarial serine protease and penetration of mice skin by the parasite.

    Science.gov (United States)

    Bahgat, Mahmoud; Aboul-Enein, Mohamed N; El Azzouny, Aida A; Maghraby, Amany; Ruppel, Andreas; Soliman, Wael M

    2009-01-01

    A cyclohexanecarboxamide derivative, N-phenyl-N-[1-(piperidine-1-carbonyl)cyclohexyl] benzamide (MNRC-5), was evaluated for its inhibitory effects on Schistosoma mansoni cercarial serine protease activity and cercarial penetration. MNRC-5 exerted an inhibitory effect on S. mansoni cercarial serine protease at serial concentrations of the specific chromogenic substrate Boc-Val-Leu-Gly-Arg-PNA for such enzyme family and the inhibitory coefficient (Ki) value was deduced. Moreover, topical treatment of mice tails with the most potent inhibitory concentration of MNRC-5 formulated in jojoba oil successfully blocked cercarial penetration as demonstrated by a significant reduction (75%; p jojoba oil base containing no MNRC-5. In addition, the IgM and IgG reactivities to crude S. mansoni cercarial, worm and egg antigens were generally lower in sera from treated infected mice than untreated infected mice. In conclusion, we report on a new serine protease inhibitor capable for blocking penetration of host skin by S. mansoni cercariae as measured by lowering worm burden and decrease in the levels of both IgM and IgG towards different bilharzial antigens upon topical treatment.

  2. Prevalence of Schistosoma mansoni Infection in Four Health Areas of Kisantu Health Zone, Democratic Republic of the Congo.

    Science.gov (United States)

    Khonde Kumbu, R; Mbanzulu Makola, K; Bin, Lu

    2016-01-01

    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 education and promote behavioral changes in children towards schistosomiasis. PMID:27579346

  3. Surface expression patterns of defined glycan antigens change during Schistosoma mansoni cercarial transformation and development of schistosomula

    NARCIS (Netherlands)

    Smit, C.H.; Homann, A.; Hensbergen, V.P. van; Schramm, G.; Haas, H. de; Diepen, A. van; Hokke, C.H.

    2015-01-01

    During the complex lifecycle of Schistosoma mansoni, a large variety of glycans is expressed. To many of these glycans, antibodies are induced by the infected host and some might be targets for vaccines or diagnostic tests. Spatial changes in glycan expression during schistosome development are larg

  4. Risk factors and spatial distribution of Schistosoma mansoni infection among primary school children in Mbita District, Western Kenya.

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    Sachiyo Nagi

    2014-07-01

    Full Text Available An increasing risk of Schistosoma mansoni infection has been observed around Lake Victoria, western Kenya since the 1970s. Understanding local transmission dynamics of schistosomiasis is crucial in curtailing increased risk of infection.We carried out a cross sectional study on a population of 310 children from eight primary schools. Overall, a total of 238 (76.8% children were infected with S. mansoni, while seven (2.3% had S. haematobium. The prevalence of hookworm, Trichuris trichiura and Ascaris lumbricoides were 6.1%, 5.2% and 2.3%, respectively. Plasmodium falciparum was the only malaria parasite detected (12.0%. High local population density within a 1 km radius around houses was identified as a major independent risk factor of S. mansoni infection. A spatial cluster of high infection risk was detected around the Mbita causeway following adjustment for population density and other potential risk factors.Population density was shown to be a major factor fuelling schistosome infection while individual socio-economic factors appeared not to affect the infection risk. The high-risk cluster around the Mbita causeway may be explained by the construction of an artificial pathway that may cause increased numbers of S. mansoni host snails through obstruction of the waterway. This construction may have, therefore, a significant negative impact on the health of the local population, especially school-aged children who frequently come in contact with lake water.

  5. Evaluation of circulating cathodic antigen (CCA urine-tests for diagnosis of Schistosoma mansoni infection in Cameroon.

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    Louis-Albert Tchuem Tchuenté

    Full Text Available BACKGROUND: The Kato-Katz is the most common diagnostic method for Schistosoma mansoni infection. However, the day-to-day variability in host egg-excretion and its low detection sensitivity are major limits for its use in low transmission zones and after widespread chemotherapy. We evaluated the accuracy of circulating cathodic antigen (CCA urine-assay as a diagnostic tool of S. mansoni. In comparison, a low sensitive CCA test (CCA-L was assessed. METHODOLOGY: THE STUDY WAS CONDUCTED IN THREE SETTINGS: two foci with single S. mansoni infections (settings A and B, and one mixed S. mansoni - S. haematobium focus (setting C. Stool and urine samples were collected from school-children on three consecutive days. Triplicate Kato-Katz readings were performed per stool sample. Each urine sample was tested with one CCA and only the first urine sample was subjected to CCA-L. Urine samples were also examined for S. haematobium eggs using the filtration method and for microhaematuria using urine reagent strips. Overall, 625 children provided three stool and three urine samples. PRINCIPAL FINDINGS: Considering nine Kato-Katz thick smears as 'reference' diagnostic test, the prevalence of S. mansoni was 36.2%, 71.8% and 64.0% in settings A, B and C, respectively. The prevalence of S. haematobium in setting C was 12.0%. The sensitivities of single Kato-Katz, CCA and CCA-L from the first stool or urine samples were 58%, 82% and 46% in setting A, 56.8%, 82.4% and 68.8% in setting B, and 49.0%, 87.7% and 55.5% in setting C. The respective specificities were 100%, 64.7% and 100%; 100%, 62.3% and 91.3%; and 100%, 42.5% and 92.0%. Mixed infection with S. haematobium did not influence the CCA test results for S. mansoni diagnosis. CONCLUSIONS/SIGNIFICANCE: Urine CCA revealed higher sensitivity than CCA-L and triplicate Kato-Katz, and produced similar prevalence as nine Kato-Katz. It seems an attractive method for S. mansoni diagnosis.

  6. Two sequential PCR amplifications for detection of Schistosoma mansoni in stool samples with low parasite load

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    Maria Cristina Carvalho do Espírito-Santo

    2012-10-01

    Full Text Available Schistosomiasis constitutes a major public health problem, with an estimated 200 million individuals infected worldwide and 700 million people living in risk areas. In Brazil there are areas of high, medium and low endemicity. Studies have shown that in endemic areas with a low prevalence of Schistosoma infection the sensitivity of parasitological methods is clearly reduced. Consequently diagnosis is often impeded due to the presence of false-negative results. The aim of this study is to present the PCR reamplification (Re-PCR protocol for the detection of Schistosoma mansoni in samples with low parasite load (with less than 100 eggs per gram (epg of feces. Three methods were used for the lysis of the envelopes of the S. mansoni eggs and two techniques of DNA extraction were carried out. Extracted DNA was quantified, and the results suggested that the extraction technique, which mixed glass beads with a guanidine isothiocyanate/phenol/chloroform (GT solution, produced good results. PCR reamplification was conducted and detection sensitivity was found to be five eggs per 500 mg of artificially marked feces. The results achieved using these methods suggest that they are potentially viable for the detection of Schistosoma infection with low parasite load.

  7. Extra-cellular matrix changes in Schistosoma mansoni-infected Biomphalaria glabrata

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    Borges Claudia Maria da Cunha

    2003-01-01

    Full Text Available Reactivity of snails against parasites exhibits a primitive focal reaction, with encapsulation, phagocytosis and destruction of parasite larvae by macrophage-like cells - the hemocytes. This reaction mimics granulomatous inflammation seen in higher animals. However, different from the latter, little is known about the participation of extra-cellular matrix in such snail defense reactions. Normal and Schistosoma mansoni-infected Biomphalaria glabrata of different strains were submitted to cytological, histological, ultrastructural and biochemical methods in order to investigate the behavior of extra-cellular tissues at the site of anti-parasite reactions. In spite of the presence of two cell-types in peripheral hemolymph, only one cell-type was present at the sites of tissue reactions. Although pre-existent collagen and elastic fibers and microfibrils sometimes appeared slightly compressed around focal reactions, no evidences of duplication, synthesis or deposition of connective-tissue extra-cellular components were observed within or around the zones of reactive cell accumulations. Thus, tissue reactions against S. mansoni in the snail B. glabrata appeared exclusively dependent on one specific population of hemocytes.

  8. Vaccination with Enzymatically Cleaved GPI-Anchored Proteins from Schistosoma mansoni Induces Protection against Challenge Infection

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    Vicente P. Martins

    2012-01-01

    Full Text Available The flatworm Schistosoma mansoni is a blood fluke parasite that causes schistosomiasis, a debilitating disease that occurs throughout the developing world. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control schistosomiasis is through immunization with an antischistosomiasis vaccine combined with drug treatment. In the search for potential vaccine candidates, numerous tegument antigens have been assessed. As the major interface between parasite and mammalian host, the tegument plays crucial roles in the establishment and further course of schistosomiasis. Herein, we evaluated the potential of a GPI fraction, containing representative molecules located on the outer surface of adult worms, as vaccine candidate. Immunization of mice with GPI-anchored proteins induced a mixed Th1/Th2 type of immune response with production of IFN-γ and TNF-α, and low levels of IL-5 into the supernatant of splenocyte cultures. The protection engendered by this vaccination protocol was confirmed by 42% reduction in worm burden, 45% reduction in eggs per gram of hepatic tissue, 29% reduction in the number of granulomas per area, and 53% reduction in the granuloma fibrosis. Taken together, the data herein support the potential of surface-exposed GPI-anchored antigens from the S. mansoni tegument as vaccine candidate.

  9. 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. PMID:18383803

  10. Schistosomiasis mansoni in Bananal (State of São Paulo, Brazil: II. Intermediate hosts

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    Horacio Manuel Santana Teles

    2002-10-01

    Full Text Available We conducted monthly snail captures in Bananal, State of São Paulo, Brazil, between March 1998 and February 2001, to identify Schistosoma mansoni vectors, estimate seasonal population changes, and delimit foci. We also evaluated the impact of improvements in city water supply and basic sanitation facilities. We identified 28,651 vector specimens, 28,438 as Biomphalaria tenagophila, 49 of them (0.2% infected with S. mansoni, and 213 as B. straminea, none of the latter infected. Vectors predominated in water bodies having some vegetation along their banks. Neither population density nor local vegetation could be linked to vector infection. We found the first infected snails in 1998 (from March to May. Further captures of infected snails ocurred, without exception, from July to December, when rainfall was least. Irrespective of season, overall temperature ranged from 16.5ºC to 21ºC; pH values, from 6.0 to 6.8. Neither factor was associated with snail population density. Frequent contact of people with the river result from wading across it, extracting sand from its bottom, fishing, washing animals, etc. Despite a marked reduction in contamination, cercaria shedding persists. Whatever the location along its urban course, contact with river Bananal, particularly of the unprotected skin, entails risks of infection.

  11. A Multiplex-PCR approach to identification of the Brazilian intermediate hosts of Schistosoma mansoni

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    Vidigal THDA

    2002-01-01

    Full Text Available Due to difficulties concerning morphological identification of planorbid snails of the genus Biomphalaria, and given a high variation of characters and in the organs with muscular tissue, we designed specific polymerase chain reaction (PCR primers for Brazilian snail hosts of Schistosoma mansoni from available sequences of internal transcribed spacer 2 (ITS2 of the ribosomal RNA gene. From the previous sequencing of the ITS2 region, one primer was designed to anchor in the 5.8S conserved region and three other species-specific primers in the 28S region, flanking the ITS2 region. These four primers were simultaneously used in the same reaction (Multiplex-PCR, under high stringency conditions. Amplification of the ITS2 region of Biomphalaria snails produced distinct profiles (between 280 and 350 bp for B. glabrata, B. tenagophila and B. straminea. The present study demonstrates that Multiplex-PCR of ITS2-DNAr showed to be a promising auxiliary tool for the morphological identification of Biomphalaria snails, the intermediate hosts of S. mansoni.

  12. Morphometric study of Schistosoma mansoni adult worms recovered from undernourished infected mice

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    Oliveira Sheilla A

    2003-01-01

    Full Text Available Some unfavourable effects of malnutrition of the host on Schistosoma mansoni worm biology and structure have been reported based upon brigthfield microscopy. This paper aims to study by morphometric techniques, some morphological parameters in male and female adult worms recovered from undernourished albino mice in comparison with parasites recovered from well-fed infected mice. Undernourished animals were fed a multideficient and essentially low protein diet (RBD diet and compared to well-fed control mice fed with the commercial diet NUVILAB. Seventy-five days post-infection with 80 cercarie (BL strain animals were sacrificed. All adult worms were fixed in 10% formalin and stained with carmine chloride. One hundred male and 60 female specimens from each group (undernourished and control were examined using an image system analysis Leica Quantimet 500C and the Sigma Scan Measurement System. The following morphometrical parameters were studied: body length and width, oral and ventral suckers, number and area of testicular lobes, length and width of ovary and uterine egg. For statistical analysis, the Student's t test for unpaired samples was applied. Significant differences (p < 0.05 were detected in body length and width, in parameters of suckers, uterine egg width, ovary length and area of testicular lobes, with lower values for specimens from undernourished mice. The nutritional status of the host has negative influence on S. mansoni adult worms, probably through unavailability of essential nutrients to the parasites.

  13. Schistosomicidal Activity of the Essential Oil of Ageratum conyzoides L. (Asteraceae against Adult Schistosoma mansoni Worms

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    Wilson R. Cunha

    2011-01-01

    Full Text Available The in vitro schistosomicidal effects of the essential oil of Ageratum conyzoides L. (Ac-EO against adult worms of Schistosoma mansoni is reported in this paper. Concerning this activity, Ac-EO was considered to be active, but less effective than the positive control (praziquantel, PZQ in terms of separation of coupled pairs, mortality, decrease in motor activity, and tegumental alterations. However, Ac-EO caused an interesting dose-dependent reduction in the number of eggs of S. mansoni. Precocene I (74.30% and (E-caryophyllene (14.23% were identified as the two major constituents of Ac-EO. These compounds were tested individually and were found to be much less effective than Ac-EO and PZQ. A mixture of the two major compounds in a ratio similar to that found in the Ac-EO was also less effective than Ac-EO, thus revealing that there are no synergistic effects between these components. These results suggest that the essential oil of A. conyzoides is very promising for the development of new schistosomicidal agents.

  14. Structural parameters, molecular properties, and biological evaluation of some terpenes targeting Schistosoma mansoni parasite.

    Science.gov (United States)

    Mafud, Ana C; Silva, Marcos P N; Monteiro, Daniela C; Oliveira, Maria F; Resende, João G; Coelho, Mayara L; de Sousa, Damião P; Mendonça, Ronaldo Z; Pinto, Pedro L S; Freitas, Rivelilson M; Mascarenhas, Yvonne P; de Moraes, Josué

    2016-01-25

    The use of natural products has a long tradition in medicine, and they have proven to be an important source of lead compounds in the development of new drugs. Among the natural compounds, terpenoids present broad-spectrum activity against infective agents such as viruses, bacteria, fungi, protozoan and helminth parasites. In this study, we report a biological screening of 38 chemically characterized terpenes from different classes, which have a hydroxyl group connected by hydrophobic chain or an acceptor site, against the blood fluke Schistosoma mansoni, the parasite responsible for schistosomiasis mansoni. In vitro bioassays revealed that 3,7-dimethyl-1-octanol (dihydrocitronellol) (10) was the most active terpene (IC50 values of 13-52 μM) and, thus, we investigated its antischistosomal activity in greater detail. Confocal laser scanning microscopy revealed that compound 10 induced severe tegumental damage in adult schistosomes and a correlation between viability and tegumental changes was observed. Furthermore, we compared all the inactive compounds with dihydrocitronellol structurally by using shape and charge modeling. Lipophilicity (miLogP) and other molecular properties (e.g. molecular polar surface area, molecular electrostatic potential) were also calculated. From the 38 terpenes studied, compound 10 is the one with the greatest flexibility, with a sufficient apolar region by which it may interact in a hydrophobic active site. In conclusion, the integration of biological and chemical analysis indicates the potential of the terpene dihydrocitronellol as an antiparasitic agent. PMID:26697994

  15. Schistosoma mansoni: parasitology and immunology of baboons vaccinated with irradiated cryopreserved schistosomula

    International Nuclear Information System (INIS)

    Young baboons (Papio cynocephalus) were vaccinated with γ-irradiated (500 Gy) cryopreserved Puerto Rican strain schistosomula of S. mansoni. Protection against heterologous, normal Kenyan Strain S. mansoni challenge infection was erratic and partial; and two putative correlates of immunity, reduced worm fecundity and change in worm location (anterior shift) were not observed. However, immunization of baboons with this vaccine resulted in a stimulated immune system. Both cellular and humoral anamnesis were demonstrable in vaccinated-challenged baboons. Schistosome infection-associated IgM hypergammaglobulinemia was also greatly reduced in vaccinated-challenged baboons. However IgG antibodies to adult, egg, and cercarial antigens were increased after challenge infection in preimmunized baboons. Vaccination appears to have resulted in a redirection of the immune system into anti-parasite channels, but this more specific immune response was insufficient to confer good protection against challenge infection in this experiment. The dampening effect of the vaccine on the hypergammaglobulinemia of schistosomiasis is another candidate for a possible ''anti-pathogenesis'' effect of irradiated schistosome larval vaccines. (author)

  16. Differential gene expression in haemocytes of the snail Biomphalaria glabrata: effects of Schistosoma mansoni infection.

    Science.gov (United States)

    Miller, A N; Raghavan, N; FitzGerald, P C; Lewis, F A; Knight, M

    2001-05-15

    Parasite encapsulation and destruction in Biomphalaria glabrata has been shown to involve the cellular component of the snail's internal defence system, the haemocytes. To identify genes involved in the immunobiology of these cells, we used the method of differential display reverse transcriptase polymerase chain reaction (DDRT-PCR) to investigate differential gene regulation in haemocytes isolated from Schistosoma mansoni exposed and unexposed snails. RNA isolated from circulating haemocytes from resistant snails (BS-90 stock), previously exposed to S. mansoni, was analysed using 12 different arbitrary primers in conjunction with an anchored Oligo d(T(11)CG) primer. Transcription profiles between haemocytes of parasite exposed and unexposed snails were compared and a total of 87 differentially regulated bands were identified and isolated. Of these, 65 bands were cloned and used as probes in Southern blots to show the presence of corresponding sequences in the snail genome. RT-PCR was performed to verify the regulation of these transcripts. DNA sequence analysis showed that the majority of the cloned sequences were novel, although a few showed a high degree of sequence similarity to other sequences in the DNA and protein databases. One of these included a differentially expressed transcript that showed a significant degree of sequence identity to E. coli transposase Tn5, an enzyme whose activity is normally associated with generating mobility and instability in the genome. PMID:11336750

  17. Schistosoma mansoni: parasitology and immunology of baboons vaccinated with irradiated cryopreserved schistosomula

    Energy Technology Data Exchange (ETDEWEB)

    Damian, R.T.; Powell, M.R.; Roberts, M.L. (Georgia Univ., Athens (USA). Dept. of Zoology); Clark, J.D. (Georgia Univ., Athens (USA). Lab. Animal Medicine); Stirewalt, M.A.; Lewis, F.A. (Biomedical Research Inst., Rockville, MD (USA))

    1985-06-01

    Young baboons (Papio cynocephalus) were vaccinated with ..gamma..-irradiated (500 Gy) cryopreserved Puerto Rican strain schistosomula of S. mansoni. Protection against heterologous, normal Kenyan Strain S. mansoni challenge infection was erratic and partial; and two putative correlates of immunity, reduced worm fecundity and change in worm location (anterior shift) were not observed. However, immunization of baboons with this vaccine resulted in a stimulated immune system. Both cellular and humoral anamnesis were demonstrable in vaccinated-challenged baboons. Schistosome infection-associated IgM hypergammaglobulinemia was also greatly reduced in vaccinated-challenged baboons. However IgG antibodies to adult, egg, and cercarial antigens were increased after challenge infection in preimmunized baboons. Vaccination appears to have resulted in a redirection of the immune system into anti-parasite channels, but this more specific immune response was insufficient to confer good protection against challenge infection in this experiment. The dampening effect of the vaccine on the hypergammaglobulinemia of schistosomiasis is another candidate for a possible ''anti-pathogenesis'' effect of irradiated schistosome larval vaccines.

  18. Schistosoma mansoni α1,3-fucosyltransferase-F generates the Lewis X antigen.

    Science.gov (United States)

    Mickum, Megan L; Rojsajjakul, Teerapat; Yu, Ying; Cummings, Richard D

    2016-03-01

    Genetic evidence suggests that the Schistosoma mansoni genome contains six genes that encode α1,3-fucosyltransferases (smFuTs). To date, the activities and specificities of these putative fucosyltransferases are unknown. As Schistosoma express a variety of fucosylated glycans, including the Lewis X antigen Galβ1-4(Fucα1-3)GlcNAcβ-R, it is likely that this family of genes encode enzymes that are partly responsible for the generation of those structures. Here, we report the molecular cloning of fucosyltransferase-F (smFuT-F) from S. mansoni, as a soluble, green fluorescent protein fusion protein and its acceptor specificity. The gene smFuT-F was expressed in HEK freestyle cells, purified by affinity chromatography, and analyzed toward a broad panel of glycan acceptors. The enzyme product of smFuT-F effectively utilizes a type II chain acceptor Galβ1-4GlcNAc-R, but notably not the LDN sequence GalNAcβ1-4GlcNAc-R, to generate Lewis X type-glycans, and smFuT-F transcripts are present in all intramammalian life stages. PMID:26582608

  19. Efficacy of Citrus reticulata and Mirazid in treatment of Schistosoma mansoni

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    Manal A Hamed

    2005-11-01

    Full Text Available This work has been carried out to investigate the effect of Schistosoma mansoni infection on mice livers after treatment with the ethanolic extract of Citrus reticulata root or the oleo-resin extract from Myrrh of Commiphora molmol tree (Mirazid, as a new antishistosomal drug. Marker enzymes for different cell organelles were measured; succinate dehydrogenase (SDH; lactate dehydrogenase (LDH and its isoenzymes; glucose-6-phosphatase (G-6-Pase; acid phosphatase (AP and 5'- nucleotidase. Liver function enzymes; aspartate aminotransferase (AST; alanine aminotransferase (ALT, and alkaline phosphatase (ALP were also estimated. Parasitological studies through ova count and worm burden will also be taken into consideration. The results showed a marked reduction in SDH, LDH, AST, and ALT enzyme activities and a significant increase in G-6-Pase, AP, 5'- nucleotidase, and ALP after S. mansoni infection. A noticeable alteration in LDH subunits were also noticed. Treatment with C. reticulata or Mirazid improved all the previous enzyme activities with a noticeable reduction in ova count and worm burden.

  20. Radiation-resistant acquired immunity of vaccinated mice to Schistosoma mansoni

    Energy Technology Data Exchange (ETDEWEB)

    Aitken, R.; Coulson, P.S.; Dixon, B.; Wilson, R.A.

    1987-11-01

    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.

  1. Antigenic community between Schistosoma mansoni and Biomphalaria glabrata: on the search of candidate antigens for vaccines

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    N Chacón

    2002-10-01

    Full Text Available We have previously confirmed the presence of common antigens between Schistosoma mansoni and its vector, Biomphalaria glabrata. Cross-reactive antigens may be important as possible candidates for vaccine and diagnosis of schistosomiasis. Sera from outbred mice immunized with a soluble Biomphalaria glabrata antigen (SBgA of non-infected B. glabrata snails recognized molecules of SBgA itself and S. mansoni AWA by Western blot. Recognition of several molecules of the SBgA were inhibited by pre-incubation with AWA (16, 30, 36, 60 and 155 kDa. The only specific molecule of AWA, inhibited by SBgA, was a 120 kDa protein. In order to determine which epitopes of SBgA were glycoproteins, the antigen was treated with sodium metaperiodate and compared with non-treated antigen. Molecules of 140, 60 and 24 kDa in the SBgA appear to be glycoproteins. Possible protective effects of the SBgA were evaluated immunizing outbred mice in two different experiments using Freund's Adjuvant. In the first one (12 mice/group, we obtained a significant level of protection (46% in the total worm load, with a high variability in worm recovery. In the second experiment (22 mice/group, no significant protection was observed, neither in worm load nor in egg production per female. Our results suggest that SBgA constitutes a rich source of candidate antigens for diagnosis and prophylactic studies.

  2. Schistosoma mansoni: respuesta celular hepática de ratones Balb/c infectados unisexualmente

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    Wolfan Araque

    2006-12-01

    Full Text Available The granulomatous response in animals infected with Schistosoma mansoni is attributed to the host reaction against the eggs, although the role of the adult worm is still controversial. The hepatic inflammatory response was studied in BALB/c mice unisexually (UNI infected with cercariae of S. mansoni by histopatology, immunofluorescence, immunohistochemistry and immunoelectronmicroscopy. The size of inflammatory infiltrate in liver of UNI infected mice, mean ± SD (33,9 ± 18, 86 µm2, the cells present included macrophages, lymphocytes, plasmocytes and few eosinophils. CD4+ and CD8+ cells in UNI infected mice were observed ( 2 to 4 cells/µm2 close to the worms and two patterns, either diffuse or in clusters in distant zones, in UNI and bisexual infections (BIS. The activated macrophages were observed close to worms and to schistosomal pigment. The results suggest that the adult worm is capable of inducing hepatic inflammatory response without granuloma formation, which elicit a significant in vivo macrophage and lymphocyte infiltrate, with probable implications in the pathogenesis of the murine schistosomiasis

  3. Miltefosine lipid nanocapsules: Intersection of drug repurposing and nanotechnology for single dose oral treatment of pre-patent schistosomiasis mansoni.

    Science.gov (United States)

    El-Moslemany, Riham M; Eissa, Maha M; Ramadan, Alyaa A; El-Khordagui, Labiba K; El-Azzouni, Mervat Z

    2016-07-01

    A dual drug repurposing/nanotechnological approach was used to develop an alternative oral treatment for schistosomiasis mansoni using miltefosine (MFS), an anticancer alkylphosphocholine, and lipid nanocapsules (LNCs) as oral nanovectors. We demonstrated earlier that MFS possesses significant activity against different developmental stages of Schistosoma mansoni in the mouse model using 5 successive 20mg/kg/day oral doses. Moreover, an effective single dose (20mg/kg) oral treatment against the adult stage of S. mansoni in mice was developed using LNCs, particularly modified with CTAB, a positive charge imparting agent (MFS-LNC-CTAB(+)), or oleic acid as membrane permeabilizer (MFS-LNC-OA). Efficacy enhancement involved, at least in part, targeting of the worm tegument with MFS-LNCs as a new therapeutic entity. As the tegument surface charge and composition may differ in pre-patent stages of the parasite, it was of importance in the present study to assess the efficacy of a single oral dose of the two MFS-LNC formulations against invasive and immature stages for potential advantage relative to praziquantel. Results indicated potent schistosomicidal effects against both invasive and immature stages of S. mansoni in infected mice, efficacy being both formulation and developmental stage dependent. This was indicated by the significant reduction in the total worm burden of the invasive stage by 91.6% and 76.8% and the immature stage by 82.7% and 96.7% for MFS-LNC-CTAB+ and MFS-LNC-OA, respectively. Histopathological findings indicated amelioration of hepatic pathology with regression of the granulomatous inflammatory reaction and reduction in granulomas number and size, verifying marked improvement in architecture of hepatic lobules. From a clinical perspective, MFS-LNCs offer potential as an alternative single oral dose nanomedicine with a wide therapeutic profile for the mass chemotherapy of schistosomiasis mansoni. PMID:27039667

  4. Long term study on the effect of mollusciciding with niclosamide in stream habitats on the transmission of schistosomiasis mansoni after community-based chemotherapy in Makueni District, Kenya

    DEFF Research Database (Denmark)

    Kariuki, Henry C.; Madsen, Henry; Ouma, John H.;

    2013-01-01

    BACKGROUND: Schistosoma mansoni infection is a persistent public health problem in many Kenyan communities. Although praziquantel is available, re-infection after chemotherapy treatment is inevitable, especially among children. Chemotherapy followed by intermittent mollusciciding of habitats...

  5. Bioactivity of miltefosine against aquatic stages of Schistosoma mansoni, Schistosoma haematobium and their snail hosts, supported by scanning electron microscopy

    OpenAIRE

    El Bardicy Samia; Eissa Maha M; Tadros Menerva

    2011-01-01

    Abstract Background Miltefosine, which is the first oral drug licensed for the treatment of leishmaniasis, was recently reported to be a promising lead compound for the synthesis of novel antischistosomal derivatives with potent activity in vivo against different developmental stages of Schistosoma mansoni. In this paper an in vitro study was carried out to investigate whether it has a biocidal activity against the aquatic stages of Schistosoma mansoni and its snail intermediate host, Biompha...

  6. A very high infection intensity of Schistosoma mansoni in a Ugandan Lake Victoria Fishing Community is required for association with highly prevalent organ related morbidity.

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    Edridah M Tukahebwa

    Full Text Available BACKGROUND: In schistosomiasis control programmes using mass chemotherapy, epidemiological and morbidity aspects of the disease need to be studied so as to monitor the impact of treatment, and make recommendations accordingly. These aspects were examined in the community of Musoli village along Lake Victoria in Mayuge district, highly endemic for Schistosoma mansoni infection. METHODOLOGY AND PRINCIPAL FINDINGS: A cross sectional descriptive study was undertaken in a randomly selected sample of 217 females and 229 males, with a mean age of 26 years (SD ± 16, range 7-76 years. The prevalence of S. mansoni was 88.6% (95% CI: 85.6-91.5. The geometric mean intensity (GMI of S. mansoni was 236.2 (95% CI: 198.5-460.9 eggs per gram (epg faeces. Males had significantly higher GMI (370.2 epg than females (132.6 epg and age was also significantly associated with intensity of infection. Levels of water contact activities significantly influenced intensity of infection and the highest intensity of infection was found among people involved in fishing. However, organomegaly was not significantly associated with S. mansoni except for very heavy infection (>2000 epg. Liver image patterns C and D indicative of fibrosis were found in only 2.2% and 0.2%, respectively. S. mansoni intensity of infection was associated with portal vein dilation and abnormal spleen length. Anaemia was observed in 36.4% of the participants but it was not associated with S. mansoni infection intensity. Considering growth in children as one of the morbidity indicators of schistosomiasis, intensity of S. mansoni was significantly associated with stunting. CONCLUSION: Although organ-related morbidity, with the exception of periportal fibrosis, and S. mansoni infections were highly prevalent, the two were only associated for individuals with very high infection intensities. These results contrast starkly with reports from Ugandan Lake Albert fishing communities in which periportal fibrosis

  7. Strukturelle Charakterisierung hämolymphproteingebundener N-Glykane und immunhistochemische Lokalisierung antigener Strukturen von Biomphalaria glabrata, die mit Glykokonjugaten des Humanparasiten Schistosoma mansoni kreuzreagieren

    OpenAIRE

    Lehr, Tobias

    2007-01-01

    In der vorliegenden Arbeit wurden N-Glykane der Zwischenwirtsschnecke Biomphala¬ria glabrata, die mit Glykokonjugaten des Humanparasiten Schistosoma mansoni serolo¬gisch kreuzreagieren, strukturell charakterisiert. Dazu waren die N-Glykane aus Hämolymphproteinen nicht-infizierter Schnecken nach proteolytischem Verdau enzyma¬tisch freigesetzt, durch Immunaffinitätschromatographie unter Verwendung von immobilisierten Antikörpern gegen lösliche Eiantigene von S. mansoni (anti-SEA) angereichert, ...

  8. Schistosoma mansoni Antigens Modulate Experimental Allergic Asthma in a Murine Model: a Major Role for CD4+ CD25+ Foxp3+ T Cells Independent of Interleukin-10▿

    OpenAIRE

    Pacífico, Lucila G. G.; Marinho, Fábio A. V.; Fonseca, Cristina T; Michele M Barsante; Pinho, Vanessa; Sales-Junior, Policarpo A.; Luciana S Cardoso; Araújo, Maria Ilma; Carvalho, Edgar M; Cassali, Geovanni D; Teixeira, Mauro M; Oliveira, Sergio C.

    2008-01-01

    In areas where schistosomiasis is endemic, a negative correlation is observed between atopy and helminth infection, associated with a low prevalence of asthma. We investigated whether Schistosoma mansoni infection or injection of parasite eggs can modulate airway allergic inflammation in mice, examining the mechanisms of such regulation. We infected BALB/c mice with 30 S. mansoni cercariae or intraperitoneally injected 2,500 schistosome eggs, and experimental asthma was induced by ovalbumin (...

  9. A esquistossomose mansoni no contexto da política de saúde brasileira Schistosoma mansoni in the context of the Brazilian health policy

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    Sandra Helena Cerrato Tibiriçá

    2011-01-01

    Full Text Available São muitos os fatores envolvidos na determinação da emergência e reemergência de doenças infecciosas. No caso da esquistossomose destacam-se os fatores biológicos como os relacionados ao habitat, às mutações e adaptações de microrganismos e hospedeiros, à resposta imunológica do hospedeiro e às adaptações bioecológicas de hospedeiros intermediários. Somam-se a esses, os não menos importantes fatores relacionados à gestão política, ocupação do ambiente e alocação de recursos financeiros. O Brasil reúne, hoje, importantes condições ecoepidemiológicas para a reemergência da esquistossomose e aumento da prevalência de algumas formas graves como mielorradiculopatia esquistossomótica, principalmente em áreas de baixa endemicidade. A expansão de suas fronteiras atinge os meios urbanos e rurais, destinados ao trabalho ou ao lazer, com comprometimento inclusive de setores de renda como o ecoturismo. Os avanços nas pesquisas acerca dos hospedeiros intermediário e definitivo do Schistosoma mansoni, para se transformarem em benefícios públicos, necessitam da sustentabilidade gerencial pública comprometida, interdisciplinar, fortalecida nas diferentes esferas de governo, vinculada ás sociedades civis tecnicamente capacitadas ao gerenciamento e comprometidas com as necessidades de saúde da população.There are many factors involved in the determination of the emergence and reemergence of infectious diseases. In the case of Schistosomiasis biological factors are highlighted as related to the habitat, to the microorganisms and hosts adaptations and mutations, to the immunologic reply of the host and to the bio-ecology adaptations of intermediate hosts. These are added to the not less important factors related to the management politics, occupation of the environment and allocation of financial resources. Brazil congregates, today, an important echo-epidemiologic conditions for the reemergence of Schistosomiasis. The

  10. "In vivo" leukocyte chemotaxis in experimental mice Schistosoma mansoni infection Quimiotaxia de leucócitos "in vivo" na infecção experimental por Schistosoma mansoni

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    Kirte Maria Teixeira

    1994-06-01

    Full Text Available The "in vivo" chemotaxis was studied in C57B1/10 mice 10, 30, 50 and 60 days after a Schistosoma mansoni infection in comparison to a control group (uninfected mice. Staphylococcal protein A was injected into a connective tissue air pouch of control and experimental mice and the leukocyte chemotaxis was counted. A decrease in polymorphonuclear (PMN leukocyte response was found in infected mice in comparison to the control group (pA quimiotaxia de leucócitos "in vivo" foi avaliada em camundongos da linhagem C57B1/10 e estudada 10, 30, 50 e 60 dias após a infecção por Schistosoma mansoni. A proteína A foi utilizada como quimiotático e injetada no tecido conjuntivo no dorso dos camundongos dos grupos experimentais e controle. Nos grupos experimentais foi observado uma diminuição na resposta dos leucócitos polimorfonucleares (PMN em comparação com o grupo controle (p<0.05. Os camundongos estudados 10 dias após a infecção, mostraram uma diminuição na resposta quimiotática de leucócitos PMN, comparando com o grupo controle (p<0.05 e este dado tornou-se mais evidente nos grupos experimentais estudados 30 e 50 dias após a infecção. Apesar da resposta quimiotática dos leucócitos PMN nos camundongos estudados 60 dias após a infecção aumentarem em comparação aos animais analisados 50 dias após a infecção, este aumento foi bem menor em relação ao grupo controle. A resposta quimiotática dos mononucleares não apresentou diferença significativa entre camundongos experimentais e controles

  11. 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

  12. Association of Schistosoma mansoni-specific IgG and IgE antibody production and clinical schistosomiasis status in a rural area of Minas Gerais, Brazil.

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    Deborah Negrão-Corrêa

    Full Text Available BACKGROUND: Studies in murine models and human populations have indicated that the collagen-rich granulomatous response against parasite eggs trapped in the liver is associated with the development of severe hepatosplenic schistosomiasis, characterized by periportal fibrosis and portal hypertension. The role of the humoral response in parasite susceptibility has been well established, but its participation in disease severity remains poorly understood. In this work, we evaluated the relationship between parasite-reactive IgE and IgG levels and schistosomiasis morbidity in infected patients with similar parasite burdens. METHODOLOGY/PRINCIPAL FINDINGS: Ninety-seven Schistosoma mansoni-infected individuals were subjected to clinical examination and abdominal ultrasound analysis. IgG reactivity and IgE concentration against Schistosoma mansoni soluble egg antigens (SEA and adult worm antigen preparation (SWAP were evaluated by ELISA assay. Multivariable linear regression models were used to evaluate the relationship between parasite-reactive antibodies and the co-variables investigated. The study population showed low parasite burden (median 30 eggs/g feces, constant re-infection, and signs of fibrosis was detected in more than 30% of individuals. Most infected individuals showed IgG reactivity, and the median concentrations of IgE anti-SEA and anti-SWAP antibodies were 1,870 and 1,375 ng/mL, respectively. There was no association between parasite burden and antibody response or any parameter of disease severity. However, IgG anti-SWAP level was positively associated with morbidity parameters, such as spleen size and thickness of portal vein at the entrance and secondary branch. In contrast, the data also revealed independent inverse correlations between concentration of parasite-reactive IgE and gallbladder wall thickness, a marker of fibrosis in schistosomiasis. CONCLUSIONS/SIGNIFICANCE: The data indicate that IgG anti-SWAP is positively

  13. 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.

  14. Schistosoma mansoni Tegument (Smteg) Induces IL-10 and Modulates Experimental Airway Inflammation

    Science.gov (United States)

    2016-01-01

    Background Previous studies have demonstrated that S. mansoni infection and inoculation of the parasite eggs and antigens are able to modulate airways inflammation induced by OVA in mice. This modulation was associated to an enhanced production of interleukin-10 and to an increased number of regulatory T cells. The S. mansoni schistosomulum is the first stage to come into contact with the host immune system and its tegument represents the host-parasite interface. The schistosomula tegument (Smteg) has never been studied in the context of modulation of inflammatory disorders, although immune evasion mechanisms take place in this phase of infection to guarantee the persistence of the parasite in the host. Methodology and Principal Findings The aim of this study was to evaluate the Smteg ability to modulate inflammation in an experimental airway inflammation model induced by OVA and to characterize the immune factors involved in this modulation. To achieve the objective, BALB/c mice were sensitized with ovalbumin (OVA) and then challenged with OVA aerosol after Smteg intraperitoneal inoculation. Protein extravasation and inflammatory cells were assessed in bronchoalveolar lavage and IgE levels were measured in serum. Additionally, lungs were excised for histopathological analyses, cytokine measurement and characterization of the cell populations. Inoculation with Smteg led to a reduction in the protein levels in bronchoalveolar lavage (BAL) and eosinophils in both BAL and lung tissue. In the lung tissue there was a reduction in inflammatory cells and collagen deposition as well as in IL-5, IL-13, IL-25 and CCL11 levels. Additionally, a decrease in specific anti-OVA IgE levels was observed. The reduction observed in these inflammatory parameters was associated with increased levels of IL-10 in lung tissues. Furthermore, Smteg/asthma mice showed high percentage of CD11b+F4/80+IL-10+ and CD11c+CD11b+IL-10+ cells in lungs. Conclusion Taken together, these findings

  15. Venus kinase receptors control reproduction in the platyhelminth parasite Schistosoma mansoni.

    Science.gov (United States)

    Vanderstraete, Mathieu; Gouignard, Nadège; Cailliau, Katia; Morel, Marion; Hahnel, Steffen; Leutner, Silke; Beckmann, Svenja; Grevelding, Christoph G; Dissous, Colette

    2014-05-01

    The Venus kinase receptor (VKR) is a single transmembrane molecule composed of an intracellular tyrosine kinase domain close to that of insulin receptor and an extracellular Venus Flytrap (VFT) structure similar to the ligand binding domain of many class C G protein coupled receptors. This receptor tyrosine kinase (RTK) was first discovered in the platyhelminth parasite Schistosoma mansoni, then in a large variety of invertebrates. A single vkr gene is found in most genomes, except in S. mansoni in which two genes Smvkr1 and Smvkr2 exist. VKRs form a unique family of RTKs present only in invertebrates and their biological functions are still to be discovered. In this work, we show that SmVKRs are expressed in the reproductive organs of S. mansoni, particularly in the ovaries of female worms. By transcriptional analyses evidence was obtained that both SmVKRs fulfill different roles during oocyte maturation. Suppression of Smvkr expression by RNA interference induced spectacular morphological changes in female worms with a strong disorganization of the ovary, which was dominated by the presence of primary oocytes, and a defect of egg formation. Following expression in Xenopus oocytes, SmVKR1 and SmVKR2 receptors were shown to be activated by distinct ligands which are L-Arginine and calcium ions, respectively. Signalling analysis in Xenopus oocytes revealed the capacity of SmVKRs to activate the PI3K/Akt/p70S6K and Erk MAPK pathways involved in cellular growth and proliferation. Additionally, SmVKR1 induced phosphorylation of JNK (c-Jun N-terminal kinase). Activation of JNK by SmVKR1 was supported by the results of yeast two-hybrid experiments identifying several components of the JNK pathway as specific interacting partners of SmVKR1. In conclusion, these results demonstrate the functions of SmVKR in gametogenesis, and particularly in oogenesis and egg formation. By eliciting signalling pathways potentially involved in oocyte proliferation, growth and migration

  16. Venus kinase receptors control reproduction in the platyhelminth parasite Schistosoma mansoni.

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    Mathieu Vanderstraete

    2014-05-01

    Full Text Available The Venus kinase receptor (VKR is a single transmembrane molecule composed of an intracellular tyrosine kinase domain close to that of insulin receptor and an extracellular Venus Flytrap (VFT structure similar to the ligand binding domain of many class C G protein coupled receptors. This receptor tyrosine kinase (RTK was first discovered in the platyhelminth parasite Schistosoma mansoni, then in a large variety of invertebrates. A single vkr gene is found in most genomes, except in S. mansoni in which two genes Smvkr1 and Smvkr2 exist. VKRs form a unique family of RTKs present only in invertebrates and their biological functions are still to be discovered. In this work, we show that SmVKRs are expressed in the reproductive organs of S. mansoni, particularly in the ovaries of female worms. By transcriptional analyses evidence was obtained that both SmVKRs fulfill different roles during oocyte maturation. Suppression of Smvkr expression by RNA interference induced spectacular morphological changes in female worms with a strong disorganization of the ovary, which was dominated by the presence of primary oocytes, and a defect of egg formation. Following expression in Xenopus oocytes, SmVKR1 and SmVKR2 receptors were shown to be activated by distinct ligands which are L-Arginine and calcium ions, respectively. Signalling analysis in Xenopus oocytes revealed the capacity of SmVKRs to activate the PI3K/Akt/p70S6K and Erk MAPK pathways involved in cellular growth and proliferation. Additionally, SmVKR1 induced phosphorylation of JNK (c-Jun N-terminal kinase. Activation of JNK by SmVKR1 was supported by the results of yeast two-hybrid experiments identifying several components of the JNK pathway as specific interacting partners of SmVKR1. In conclusion, these results demonstrate the functions of SmVKR in gametogenesis, and particularly in oogenesis and egg formation. By eliciting signalling pathways potentially involved in oocyte proliferation, growth

  17. Liver and serum soluble protein changes and pathomorphology in undernourished mice with acute Schistosomiasis mansoni

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    Eridan M. Coutinho

    1991-12-01

    Full Text Available Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group. Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.No presente estudo os pesos corporal, hepático e esplénico; a morfologia patológica do fígado, baço e intestinos; e as modificações das proteínas solúveis hepáticas e séricas, foram os parâmetros investigados em camundongos albinos Suíços desnutridos e infectados com S. mansoni. Os animais desnutridos não infectados apresentaram relações fígado/peso corporal e baço! peso corporal com valores menores do que os animais controles (grupo caseina a 22,60%. Camundongos infectados mostraram esses índices mais elevados, independentemente do tipo de dieta. O subgrupo de camundongos desnutridos infectados apresentou, no fígado, reação periovular exsudativa persistente. O conteúdo de proteínas solúveis no fígado e no soro também mostrou-se reduzido nos camundongos infectados desnutridos. Diferença significativa foi detectada quanto às gamaglobulinas, comparando-se animais infectados com não infectados alimentados com a dieta controle II, valores mais altos ocorrendo no grupo dos

  18. Verificação de antagonismo entre larvas de Schistosoma mansoni e larvas de outros Digenea em Biomphalaria tenagophila, molusco planobídeo de criadouro natural situado na região de Campinas, SP, Brasil Verification of the antagonism between larvae of Schistosoma mansoni and those of other Digenea in Biomphalaria tenagophila, a planorbid molusc from a natural breeding ground in the region of Campinas, SP, Brazil

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    Soely Maria Pissini Machado

    1988-12-01

    Full Text Available Foi observado o comportamento de larvas de S. mansoni em moluscos prévia e naturalmente infectados por larvas de outros Digenea. Foi verificado que as larvas de S. mansoni não se desenvolveram nos moluscos previamente infectados com purcocercárias longifurcadas com ocelos ou com furcocercárias longifurcadas sem ocelos. Observou-se resistência parcial ao desenvolvimento de S. mansoni nos moluscos previamente infectados por equinostomocercárias ou por distomocercárias com acúleo. A ausência de reação amebocitária em torno dos esporocistos de S. mansoni nos moluscos infectados por outros digenéticos parece indicar a não participação dos amebócitos na resistência oferecida ao desenvolvimento das larvas de S. mansoni.The objective of the present work is to study the development of S. mansoni larvae in snails found naturally infected by other digenetic trematode larvae. It was found that S. mansoni larvae did not develop in snails previoulsy infected by furcicercariae either with or without ocelli. Partial resistance to the development of S. mansoni was observed in snails previously infected by cercariae of Echinostomatidae or by cercariae with aculeus of Distomata. Absence of amoebocitary reaction around the S. mansoni sporocysts in snails previously infected by other digenetic trematodes indicates that amoebocytes did not play any role in the resistance mechanism.

  19. 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.

  20. Garlic attenuates histological and histochemical alterations in livers of Schistosoma mansoni infected mice.

    Science.gov (United States)

    Mahmoud, Y I; Riad, N H; Taha, H

    2016-08-01

    Interest in screening for new anti-schistosomal agents is growing because of increased concerns about resistance to and safety of praziquantel. We investigated the anti-schistosomal action of prophylactic and therapeutic doses of garlic on the histological and histochemical alterations caused by Schistosoma mansoni infection. Livers of infected mice were characterized by granulomas, periportal inflammation and fibrosis, hepatocyte vacuolation, fatty degeneration and necrosis, and hypertrophy and pigmentation of Kupffer cells. Significant depletion of carbohydrates and increased lipid vacuoles also were observed. All garlic regimens caused suppression of granuloma formation and amelioration of histological and histochemical changes; the continuous treatment protocol produced the best results. Garlic appears to be a safe and economical anti-schistosomal adjuvant for attenuating the pathogenicity of schistosomiasis. PMID:27045197

  1. Purification and characterization of an elastinolytic proteinase secreted by cercariae of Schistosoma mansoni.

    Science.gov (United States)

    McKerrow, J H; Pino-Heiss, S; Lindquist, R; Werb, Z

    1985-03-25

    An elastinolytic proteinase secreted by tissue-invasive larvae of Schistosoma mansoni has been purified to homogeneity. Size-exclusion chromatography and chromatofocusing were used to purify the enzyme 18-fold from crude larval secretions. The native enzyme has a molecular weight of 30,000, a pI of 8, a pH optimum of 9, and a calcium dependence of 2 mM. A second Mr 17,000 form of the enzyme was present in crude secretions and appears to be an autoproteolysis product. The enzyme is a serine proteinase that preferentially binds tetrapeptide inhibitors or substrates with an aromatic or hydrophobic residue at the P-1 site. In addition to being active against elastin, the enzyme degrades Azocoll, gelatin, laminin, fibronectin, keratin, and type IV collagen.

  2. Specific immunoglobulin measurements related to exposure and resistance to Schistosoma mansoni infection in Sudanese canal cleaners

    DEFF Research Database (Denmark)

    Satti, M.Z.; Lind, Peter; Vennervald, B.J.;

    1996-01-01

    The present work comprises a longitudinal study of Schistosoma mansoni infection in occupationally hyper-exposed canal cleaners in the Sudan and the influence of chemotherapy on humoral immune parameters. The study groups included chronically infected canal cleaners (n = 19), newly recruited canal...... cleaners (n = 17), normally exposed adults (n = 31), school children (n = 46) and Sudanese negative controls (n = 48). Previous studies of the same canal cleaners have demonstrated that chronically infected canal cleaners were more resistant to reinfection than newly recruited canal cleaners. ELISA...... was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection...

  3. Effect of artemether on cytokine profile and egg induced pathology in murine schistosomiasis mansoni

    Directory of Open Access Journals (Sweden)

    Neveen A. Madbouly

    2015-11-01

    Full Text Available Artemether (ART, the methylated derivative of artemisinin, is an efficacious antimalarial drug that also displays antischistosomal properties. This study was designed to evaluate the immunomodulatory action of a single intramuscular dose (50 mg/kg body weight of ART in comparison with PZQ treatment (42 days PI. ART administration was 7, 14, 21 and 45 days PI. ART effect was studied parasitologically, histopathologically and immunologically. It was found that maximum effect was reached when ART treatment interfered with 14 or 21 days old schistosomula. ART treatment 14 or 21 days PI was associated with shift from Th2 to Th1 predominancy (decrease in IL-4 and upgrading of serum IFN-γ levels. In conclusion, ART is a promising drug in control of schistosomiasis mansoni due to its reductive effect on worm burden and its role in improvement of hepatic granulomatous lesions.

  4. Effects of non-specific immunopotentiators in experimental Schistosoma mansoni infection. II. Corynebacterium parvum.

    Science.gov (United States)

    Teixeira, K M; Coutinho, E M; Abath, F G; Montenegro, S M

    1996-01-01

    The effects of Corynebacterium parvum on host protection, tissue reaction and "in vivo" chemotaxis in Schistosoma mansoni infected mice were studied. The C. parvum was given intraperitoneally using a dose of 0.7 mg, twice a week (for 4 weeks), thirty days before (prophylactic treatment) or after infection (curative treatment). The host protection was evaluated through the recovery of adult worms by liver perfusion and was lower in the prophylactic group as compared to the control group (p = 0.018), resulting in 44% protection. The "in vivo" leukocyte response in both prophylactic and curative groups was higher as compared to the infected/non treated group (p = 0.009 and p = 0.003, respectively). Tissue reactions were described in the experimental and control groups, but there were not remarkable differences among them. The possible biological implications and relevance of the findings for the defensive response of the host and control of schistosomiasis are discussed. PMID:9293078

  5. Surgical indication in Schistosomiasis mansoni portal hypertension: follow-up from 1985 to 2001

    Directory of Open Access Journals (Sweden)

    Maria José Conceição

    2002-10-01

    Full Text Available The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3% male (14-53 years old were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9% of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life.

  6. 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

    Directory of Open Access Journals (Sweden)

    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.

  7. Evaluation of urine CCA assays for detection of Schistosoma mansoni infection in Western Kenya.

    Directory of Open Access Journals (Sweden)

    Hillary L Shane

    Full Text Available Although accurate assessment of the prevalence of Schistosoma mansoni is important for the design and evaluation of control programs, the most widely used tools for diagnosis are limited by suboptimal sensitivity, slow turn-around-time, or inability to distinguish current from former infections. Recently, two tests that detect circulating cathodic antigen (CCA in urine of patients with schistosomiasis became commercially available. As part of a larger study on schistosomiasis prevalence in young children, we evaluated the performance and diagnostic accuracy of these tests--the carbon test strip designed for use in the laboratory and the cassette format test intended for field use. In comparison to 6 Kato-Katz exams, the carbon and cassette CCA tests had sensitivities of 88.4% and 94.2% and specificities of 70.9% and 59.4%, respectively. However, because of the known limitations of the Kato-Katz assay, we also utilized latent class analysis (LCA incorporating the CCA, Kato-Katz, and schistosome-specific antibody results to determine their sensitivities and specificities. The laboratory-based CCA test had a sensitivity of 91.7% and a specificity of 89.4% by LCA while the cassette test had a sensitivity of 96.3% and a specificity of 74.7%. The intensity of the reaction in both urine CCA tests reflected stool egg burden and their performance was not affected by the presence of soil transmitted helminth infections. Our results suggest that urine-based assays for CCA may be valuable in screening for S. mansoni infections.

  8. Experiences with the control of schistosomiasis mansoni in two foci in Central Africa

    Directory of Open Access Journals (Sweden)

    B. Gryseels

    1992-01-01

    Full Text Available Experiences with population-based chemotherapy and other methods for the control of schistosomiasis mansoni in two subsaharan foci are described. In the forest area of Maniema (Zaire, intense transmission of Schistosoma mansoni, high prevalences and intensities of infection, and important morbidity have been documental. Taking into account the limited financial means and the poor logistic conditions, the control strategy has been based mainly on targeted chemotherapy of heavily infected people (>600 epg. After ten years of intervention, prevalences and intensities have hardly been affected, but the initial severe hepatosplenic morbidity has almost disappeared. In Burundi, a national research and control programme has been initiated in 1982. Prevalences, intensities and morbidity were moderate, transmission was focal and erratic in time and space. A more structural control strategy was developed, based on screening and selective therapy, health education, sanitation and domestic water supply. Prevalences and intensities have been considerably reduced, though the results show focal and unpredicatable variations. Transmission and reinfection were not signifcantly affected by chemotherapy alone, and eventual outcome of repeated selective treatment appears to be limited by the sensitivity of the screening method. Intestinal morbidity was strongly reduced by community-based selective treatment, but hepatosplenic enlargement was hardly affected; this is possibly due to the confounding impact of increasing malaria morbidity. The experiences show the importance of local structures and conditions for the development of an adapted control strategy. It is further concluded that population-based chemotherapy is a highly valid tool for the rapid control of morbidity, but should in most operational conditions not be considered as a tool for transmission control. Integration of planning, execution and surveillance in regular health services...

  9. Cytokine patterns in experimental schistosomiasis mansoni infected mice treated with silymarin.

    Science.gov (United States)

    El-Sayed, Nagwa Mostafa; Fathy, Ghada Mahmoud; Abdel-Rahman, Sara Abdel-Rahman; El-Shafei, Mahmoud Abdel-Atei

    2016-09-01

    The purpose of this study was to determine cytokine patterns in experimental schistosomiasis mansoni infected mice treated with silymarin. The study was conducted upon 100 mice that were divided into five groups; 20 each: uninfected control group, Schistosoma mansoni infected untreated mice (infected control), infected mice treated with praziquantel (PZQ), infected mice treated with silymarin and infected mice treated with both praziquantel and silymarin. 10 mice from each group were sacrificed at 10th and 18th weeks post infection respectively. Histopathological investigations were performed. Liver sections were stained with hematoxylin-eosin and Masson's trichrome stain to evaluate changes of granuloma sizes and numbers. Serum levels of the cytokines (TNF-α, IFN-γ, IL-4 and TGF-β1) were assessed in the sera of all groups by immunoassay. The measured levels of cytokines (IFN-γ, IL-4, TNF-α, TGF-β1) were found to be significantly increased in infected mice compared to normal control. At the same time, treated groups with silymarin alone or combined with PZQ showed significant decrease in IL-4, TNF-α and TGF-β1 levels compared to infected control. On the other hand, there was a significant increase in IFN-γ level observed in all treated groups compared to infected control. In addition, the histopathological examination of the liver in the group treated with PZQ showed a reduction in the number of livers eggs granuloma at all periods of sacrification compared with the infected untreated group. However, there was more decrease in granulomas diameter in both silymarin treated group or combined with PZQ at all periods of sacrification when compared to infected untreated group. In conclusion; treatment with silymarin combined with PZQ in murine schistosomiasis could reduce hepatic fibrosis by their action on the production of pro-inflammatory cytokines. PMID:27605811

  10. Effects of non-specific immunopotentiators in experimental Schistosoma mansoni infection: II. Corynebacterium parvum Efeitos de imunopotenciadores não específicos na infecção experimental pelo Schistosoma mansoni: II. Corynebacterium parvum

    OpenAIRE

    Kirte M Teixeira; Eridan M. Coutinho; Frederico G.C. Abath; Montenegro, Silvia M. L.

    1996-01-01

    The effects of Corynebacterium parvum on host protection, tissue reaction and "in vivo" chemotaxis in Schistosoma mansoni infected mice were studied. The C. parvum was given intraperitoneally using a dose of 0.7 mg, twice a week (for 4 weeks), thirty days before (prophylactic treatment) or after infection (curative treatment). The host protection was evaluated through the recovery of adult worms by liver perfusion and was lower in the prophylactic group as compared to the control group (p = 0...

  11. Diagnosing schistosomiasis by detection of cell-free parasite DNA in human plasma.

    Directory of Open Access Journals (Sweden)

    Dominic Wichmann

    Full Text Available INTRODUCTION: Schistosomiasis (bilharzia, one of the most relevant parasitoses of humans, is confirmed by microscopic detection of eggs in stool, urine, or organ biopsies. The sensitivity of these procedures is variable due to fluctuation of egg shedding. Serological tests on the other hand do not distinguish between active and past disease. In patients with acute disease (Katayama syndrome, both serology and direct detection may produce false negative results. To overcome these obstacles, we developed a novel diagnostic strategy, following the rationale that Schistosoma DNA may be liberated as a result of parasite turnover and reach the blood. Cell-free parasite DNA (CFPD was detected in plasma by PCR. METHODOLOGY/PRINCIPAL FINDINGS: Real-time PCR with internal control was developed and optimized for detection of CFPD in human plasma. Distribution was studied in a mouse model for Schistosoma replication and elimination, as well as in human patients seen before and after treatment. CFPD was detectable in mouse plasma, and its concentration correlated with the course of anti-Schistosoma treatment. Humans with chronic disease and eggs in stool or urine (n = 14 showed a 100% rate of CFPD detection. CFPD was also detected in all (n = 8 patients with Katayama syndrome. Patients in whom no viable eggs could be detected and who had been treated for schistomiasis in the past (n = 30 showed lower detection rates (33.3% and significantly lower CFPD concentrations. The duration from treatment to total elimination of CFPD from plasma was projected to exceed one year. CONCLUSIONS/SIGNIFICANCE: PCR for detection of CFPD in human plasma may provide a new laboratory tool for diagnosing schistosomiasis in all phases of clinical disease, including the capacity to rule out Katayama syndrome and active disease. Further studies are needed to confirm the clinical usefulness of CFPD quantification in therapy monitoring.

  12. Detection of Schistosoma mansoni Antibodies in a Low-Endemicity Area Using Indirect Immunofluorescence and Circumoval Precipitin Test

    Science.gov (United States)

    Carvalho do Espírito-Santo, Maria Cristina; Pinto, Pedro Luiz; Gargioni, Cybele; Viviana Alvarado-Mora, Monica; Pagliusi Castilho, Vera Lúcia; Pinho, João Ranato Rebello; de Albuquerque Luna, Expedito José; Borges Gryschek, Ronaldo Cesar

    2014-01-01

    Parasitological diagnostic methods for schistosomiasis lack sensitivity, especially in regions of low endemicity. The objective of this study was to determine the prevalence of Schistosoma mansoni infections by antibody detection using the indirect immunofluorescence assay (IFA-IgM) and circumoval precipitin test (COPT). Serum samples of 572 individuals were randomly selected. The IFA-IgM and COPT were used to detect anti-S. mansoni antibodies. Of the patients studied, 15.9% (N = 91) were IFA-IgM positive and 5.1% (N = 29) had COPT reactions (P < 0.001 by McNemar's test). Immunodiagnostic techniques showed higher infection prevalence than had been previously estimated. This study suggests that combined use of these diagnostic tools could be useful for the diagnosis of schistosomiasis in epidemiological studies in areas of low endemicity. PMID:24639303

  13. 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

    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...... temperatures of 26-36 degrees C, and night temperatures of 15-20 degrees C were used as criteria for the prediction model. Using the same approach with host snail data indicated that most of Uganda is suitable "B. pfeifferi"/B. sudanica habitat, except for possibly the north-eastern region of the country...... climate data on precipitation, as the best ecological determinants of the S. mansoni-"B. pfeifferi"/B. sudanica system. Satellite composite models and logistic regression analysis, suggest low night time temperature as one of the significant factors inhibiting S. mansoni transmission in the south...

  14. The role of antibody affinity and titre in immunity to Schistosoma mansoni following vaccination with highly irradiated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Vignali, D.A.A.; Devey, M.E.; Bickle, Q.D.; Taylor, M.G. (London School of Hygiene and Tropical Medicine (UK))

    1990-02-01

    Sera from rabbits and rats vaccinated with highly irradiated cercariae of Schistosoma mansoni (VRabS, VRatS) were found to be of substantially higher affinity than sera from CBA mice vaccinated four times (4 x CVMS), single sex sera (SSS) or chronic infection sera (CIS). In contrast, immunoprecipitation studies demonstrated that sera from vaccinated LA mice (LVMS) recognized {sup 125}I-labelled schistosomular surface antigens more intensely than sera from vaccinated HA mice (HVMS). However, peritoneal macrophages from HA and LA mice in the presence of HVMS, LVMS or 4 x CVMS, and naive macrophages activated in vitro with interferon-gamma (IFN-{gamma})/lipopolysaccharide (LPS) mediated comparable levels of schistosomula killing in vitro. The experiments described here provide evidence that the titre of antibody rather than its affinity may be a more critical factor in the development of optimal immunity to S. mansoni. (author).

  15. Carbohydrate metabolism alterations in Biomphalaria glabrata infected with Schistosoma mansoni and exposed to Euphorbia splendens var. hislopii latex

    OpenAIRE

    Clélia Christina Mello-Silva; Mônica Magno Vilar; Maurício Carvalho Vasconcellos; Jairo Pinheiro; Maria de Lurdes de A Rodrigues

    2010-01-01

    This paper evaluates the alterations in the glycogen content of tissues (digestive gland and cephalopedal mass) and glucose in the haemolymph of Biomphalaria glabrata BH strain infected with Schistosoma mansoni BH strain and exposed to the latex of Euphorbia splendens var. hislopii. A reduction in the glycogen deposits was observed in infected snails exposed and not exposed to latex. However, the exposure to latex caused a greater depletion of the glycogen levels in both sites analysed, espec...

  16. New insights into the molecular epidemiology and population genetics of Schistosoma mansoni in Ugandan pre-school children and mothers.

    Directory of Open Access Journals (Sweden)

    Martha Betson

    Full Text Available Significant numbers of pre-school children are infected with Schistosoma mansoni in sub-Saharan Africa and are likely to play a role in parasite transmission. However, they are currently excluded from control programmes. Molecular phylogenetic studies have provided insights into the evolutionary origins and transmission dynamics of S. mansoni, but there has been no research into schistosome molecular epidemiology in pre-school children. Here, we investigated the genetic diversity and population structure of S. mansoni in pre-school children and mothers living in lakeshore communities in Uganda and monitored for changes over time after praziquantel treatment. Parasites were sampled from children (<6 years and mothers enrolled in the longitudinal Schistosomiasis Mothers and Infants Study at baseline and at 6-, 12- and 18-month follow-up surveys. 1347 parasites from 35 mothers and 45 children were genotyped by direct sequencing of the cytochrome c oxidase (cox1 gene. The cox1 region was highly diverse with over 230 unique sequences identified. Parasite populations were genetically differentiated between lakes and non-synonymous mutations were more diverse at Lake Victoria than Lake Albert. Surprisingly, parasite populations sampled from children showed a similar genetic diversity to those sampled from mothers, pointing towards a non-linear relationship between duration of exposure and accumulation of parasite diversity. The genetic diversity six months after praziquantel treatment was similar to pre-treatment diversity. Our results confirm the substantial genetic diversity of S. mansoni in East Africa and provide significant insights into transmission dynamics within young children and mothers, important information for schistosomiasis control programmes.

  17. Structural changes in the jejunal mucosa of mice infected with Schistosoma mansoni, fed low or high protein diets

    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...

  18. LmSmdB: an integrated database for metabolic and gene regulatory network in Leishmania major and Schistosoma mansoni

    OpenAIRE

    Priyanka Patel; Vineetha Mandlik; Shailza Singh

    2015-01-01

    A database that integrates all the information required for biological processing is essential to be stored in one platform. We have attempted to create one such integrated database that can be a one stop shop for the essential features required to fetch valuable result. LmSmdB (L. major and S. mansoni database) is an integrated database that accounts for the biological networks and regulatory pathways computationally determined by integrating the knowledge of the genome sequences of the ment...

  19. Activity of Artemether and Mefloquine against Juvenile and Adult Schistosoma mansoni in Athymic and Immunocompetent NMRI Mice

    OpenAIRE

    Keiser, Jennifer; Vargas, Mireille; Doenhoff, Michael J.

    2010-01-01

    Immune effector mechanisms can enhance the activity of antischistosomal drugs. We examined the in vivo effect of single oral doses of the antimalarials artemether (400 mg/kg) and mefloquine (200 mg/kg), recently described to have promising antischistosomal properties, against juvenile and adult Schistosoma mansoni in T cell-deficient and in comparably infected age- and sex-matched immunologically intact control mice. Artemether and mefloquine are equally effective in athymic and immunocompete...

  20. Low transformation growth factor-β1 production and collagen synthesis correlate with the lack of hepatic periportal fibrosis development in undernourished mice infected with Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Andreia Ferreira Barros

    2014-04-01

    Full Text Available Undernourished mice infected (UI submitted to low and long-lasting infections by Schistosoma mansoni are unable to develop the hepatic periportal fibrosis that is equivalent to Symmers’ fibrosis in humans. In this report, the effects of the host’s nutritional status on parasite (worm load, egg viability and maturation and host (growth curves, biology, collagen synthesis and characteristics of the immunological response were studied and these are considered as interdependent factors influencing the amount and distribution of fibrous tissue in hepatic periovular granulomas and portal spaces. The nutritional status of the host influenced the low body weight and low parasite burden detected in UI mice as well as the number, viability and maturation of released eggs. The reduced oviposition and increased number of degenerated or dead eggs were associated with low protein synthesis detected in deficient hosts, which likely induced the observed decrease in transformation growth factor (TGF-β1 and liver collagen. Despite the reduced number of mature eggs in UI mice, the activation of TGF-β1 and hepatic stellate cells occurred regardless of the unviability of most miracidia, due to stimulation by fibrogenic proteins and eggshell glycoproteins. However, changes in the repair mechanisms influenced by the nutritional status in deficient animals may account for the decreased liver collagen detected in the present study.

  1. Distribution and Schistosoma mansoni infection of Biomphalaria glabrata in different habitats in a rural area in the Jequitinhonha Valley, Minas Gerais, Brazil: environmental and epidemiological aspects

    Directory of Open Access Journals (Sweden)

    Helmut Kloos

    2004-11-01

    Full Text Available This paper examines the distribution and infection of Biomphalaria glabrata with Schistosoma mansoni in all aquatic snail habitats in a rural area in the state of Minas Gerais, Brazil, in relation to physico/biotic and behavioral factors. Snail and environmental surveys were carried out semi-annually between July 2001 and November 2002 at 106 sites. Collected snails were examined in the laboratory for infection. B. glabrata densities were highest in overflow ponds, irrigation ponds, springs, canals and wells, and lowest in fishponds and water tanks. Snail densities were higher during the hot, rainy season except for streams and canals and were statistically associated with the presence of fish, pollution, and vegetation density. Tilapia fish and an unidentified Diptera larva were found to be predators of B. glabrata but ducks were not. Twenty-four of the 25 infected snails were collected in 2001(1.4% infection rate and only one in 2002, after mass chemotherapy. The occurrence of B. glabrata in all 11 snail habitats both at and away from water contact sites studied indicates widespread risk of human infection in the study area. In spite of the strong association between B. glabrata and tilapia in fishponds we do not recommend its use in schistosomiasis control for ecological reasons and its relative inefficiency in streams and dams.

  2. Biomphalaria tenagophila potencial vector of Schistosoma mansoni in the Paraná River basin (Argentina and Paraguay).

    Science.gov (United States)

    Borda, C Edgardo; Rea, María Josefa F

    2007-05-01

    Susceptibility and compatibility experiments were carried out with 700 Biomphalaria tenagophila from the Paraná River basin exposed to infection with Schistosoma mansoni. Individual infection was performed with 10 miracidia of SJ2 strain from the Paraiba valley (Brazil) originally infective to B. tenagophila. These snails were laboratory-breed progeny of B. tenagophila collected from six localities of Argentina and one from Paraguay. From Argentina: Rincón de Vences (7%) and Posadas (11%) became infected with S. mansoni and the calculation of Frandsen's index (TCP/100) shows that they were Class II poorly compatible. Those snails from Goya (22%), Maloyas (5%), and Berón de Astrada (3%) were Class III compatible to the S. mansoni. None of the 100 snails exposed from Caá-Catí became infected (Class 0 incompatible). Tested samples from Paraguay (Encarnación) were infected (20%) and compatible (Class III). It was also studied the persistence of the infection in 244 snails of the first generation (F1) of those that were susceptible from three places. It was demonstrated an increment of the susceptibility in the F1 from Maloyas (chi2 = 27.22; p = 0.0001) and Posadas (chi2 = 4.24; p = 0.04). The results point out the possibility that schistosomiasis might be able to spread into the Paraná River basin where B. tenagophila exists.

  3. Studies on the effect of antioxidant Selenium-ACE after treatment with Praziquantel and Mirazid in Schistosoma mansoni infected mice

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    Muhammad Hamdy Emam*; Mona Abd El-Rahman **; Irene Sameh Gamil** and Marwa

    2009-12-01

    Full Text Available Background: This study deals with the evaluation of parasitological, histopathological and biochemical effect of Praziquantel (PZQ and Mirazid (MZ with or without Selenium-ACE (Se-ACE on male albino mice infected with S.mansoni and trying to evaluate the antioxidant effect of Se-ACE and its role in reducing the severity of the infection. Results: The obtained results indicated that treatment with PZQ produced more reduction in worm burden and ova count/gm liver than MZ compared to the infected control group. PZQ showed the highest reduction in liver granuloma number and diameter when compared to MZ group while both drugs showed a significant effect in restoration of the liver transaminases and protein fractions towards their normal levels indicating the safety of both drugs as anti S. mansoni chemotherapeutics, Se-ACE showed a high efficacy as a co-treatment, potentiating the effect of PZQ and MZ in reducing the worm burden, ova count/gm liver, number and diameter of liver granuloma and restoration of liver transaminases and protein fractions to their normal levels during treatment of S. mansoni infection. Conclusion: the rank order of potency in protection against liver cell damage was PZQ 500 mg/kg > MZ 600 mg/kg where Se-ACE showed a couraging criterion as a co- treatment potentiating the effect of the antischistosomal medications through its anti- oxidant activity.

  4. Use of Occult Blood Detection Cards for Real-Time PCR-Based Diagnosis of Schistosoma Mansoni Infection

    Science.gov (United States)

    Schunk, Mirjam; Kebede Mekonnen, Seleshi; Wondafrash, Beyene; Mengele, Carolin; Fleischmann, Erna; Herbinger, Karl-Heinz; Verweij, Jaco J.; Geldmacher, Christof; Bretzel, Gisela; Löscher, Thomas; Zeynudin, Ahmed

    2015-01-01

    Background In Schistosoma mansoni infection, diagnosis and control after treatment mainly rely on parasitological stool investigations which are laborious and have limited sensitivity. PCR methods have shown equal or superior sensitivity but preservation and storage methods limit their use in the field. Therefore, the use of occult blood detection cards (fecal cards) for easy sampling and storage of fecal samples for further PCR testing was evaluated in a pilot study. Methodology Stool specimens were collected in a highly endemic area for S. mansoni in Ethiopia and submitted in an investigator-blinded fashion to microscopic examination by Kato-Katz thick smear as well as to real-time PCR using either fresh frozen stool samples or stool smears on fecal cards which have been stored at ambient temperature for up to ten months. Principal Findings Out of 55 stool samples, 35 were positive by microscopy, 33 and 32 were positive by PCR of frozen samples and of fecal card samples, respectively. When microscopy was used as diagnostic “gold standard”, the sensitivity of PCR on fresh stool was 94.3% (95%-CI: 86.6; 100) and on fecal cards 91.4% (95%-CI: 82.2; 100). Conclusions The use of fecal cards proved to be a simple and useful method for stool collection and prolonged storage prior to PCR based diagnosis of S. mansoni infection. This technique may be a valuable approach for large scale surveillance and post treatment assessments PMID:26360049

  5. Use of Occult Blood Detection Cards for Real-Time PCR-Based Diagnosis of Schistosoma Mansoni Infection.

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    Mirjam Schunk

    Full Text Available In Schistosoma mansoni infection, diagnosis and control after treatment mainly rely on parasitological stool investigations which are laborious and have limited sensitivity. PCR methods have shown equal or superior sensitivity but preservation and storage methods limit their use in the field. Therefore, the use of occult blood detection cards (fecal cards for easy sampling and storage of fecal samples for further PCR testing was evaluated in a pilot study.Stool specimens were collected in a highly endemic area for S. mansoni in Ethiopia and submitted in an investigator-blinded fashion to microscopic examination by Kato-Katz thick smear as well as to real-time PCR using either fresh frozen stool samples or stool smears on fecal cards which have been stored at ambient temperature for up to ten months.Out of 55 stool samples, 35 were positive by microscopy, 33 and 32 were positive by PCR of frozen samples and of fecal card samples, respectively. When microscopy was used as diagnostic "gold standard", the sensitivity of PCR on fresh stool was 94.3% (95%-CI: 86.6; 100 and on fecal cards 91.4% (95%-CI: 82.2; 100.The use of fecal cards proved to be a simple and useful method for stool collection and prolonged storage prior to PCR based diagnosis of S. mansoni infection. This technique may be a valuable approach for large scale surveillance and post treatment assessments.

  6. Aspectos imunológicos e parasitológicos em Biomphalaria tenagophila infectadas por Schistosoma mansoni e outros Digenea

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    Balan Doralice de Souza Luro

    1993-01-01

    Full Text Available Estudou-se o comportamento de amebócitos de Biomphalaria tenagophila infectadas por Schistosoma mansoni, por outros Digenea e a resistência à superinfecção, presente em infecções mistas. Foi verificada a atividade fagocitária dos amebócitos, o número destas células circulantes, a reação amebocitária nos tecidos, o perfil eletroforético da hemolinfa, além da reação de imunodifusão. Concluiu-se que moluscos infectados por outros Digenea apresentam resistência à superinfecção por S. mansoni, sendo que os amebócitos parecem não ter participação direta na destruição dos esporocistos de S. mansoni nesta eventualidade. Nos moluscos infectados observou-se maior número de amebócitos circulantes e aumento de capacidade fagocitária destas células.

  7. Biomphalaria tenagophila potencial vector of Schistosoma mansoni in the Paraná River basin (Argentina and Paraguay

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    C Edgardo Borda

    2007-03-01

    Full Text Available Susceptibility and compatibility experiments were carried out with 700 Biomphalaria tenagophila from the Paraná River basin exposed to infection with Schistosoma mansoni. Individual infection was performed with 10 miracidia of SJ2 strain from the Paraiba valley (Brazil originally infective to B. tenagophila. These snails were laboratory-breed progeny of B. tenagophila collected from six localities of Argentina and one from Paraguay. From Argentina: Rincón de Vences (7% and Posadas (11% became infected with S. mansoni and the calculation of Frandsen's index (TCP/100 shows that they were Class II poorly compatible. Those snails from Goya (22%, Maloyas (5%, and Berón de Astrada (3% were Class III compatible to the S. mansoni. None of the 100 snails exposed from Caá-Catí became infected (Class 0 incompatible. Tested samples from Paraguay (Encarnación were infected (20% and compatible (Class III. It was also studied the persistence of the infection in 244 snails of the first generation (F1 of those that were susceptible from three places. It was demonstrated an increment of the susceptibility in the F1 from Maloyas (chi2 = 27.22; p = 0.0001 and Posadas (chi2 = 4.24; p = 0.04. The results point out the possibility that schistosomiasis might be able to spread into the Paraná River basin where B. tenagophila exists.

  8. Water-contact patterns and risk factors for Schistosoma mansoni infection in a rural village of Northeast Brazil

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    SILVA Antônio Augusto Moura da

    1997-01-01

    Full Text Available Schistosomiasis mansoni in the Serrano village, municipality of Cururupu, state of Maranhão, Brazil, is a widely spread disease. The PECE (Program for the Control of Schistosomiasis, undertaken since 1979 has reduced the prevalence of S. mansoni infection and the hepatosplenic form of the disease. Nevertheless piped water is available in 84% of the households, prevalence remains above 20%. In order to identify other risk factors responsible for the persistence of high prevalence levels, a cross-sectional survey was carried out in a systematic sample of 294 people of varying ages. Socioeconomic, environmental and demographic variables, and water contact patterns were investigated. Fecal samples were collected and analyzed by the Kato-Katz technique. Prevalence of S. mansoni infection was 24.1%, higher among males (35.5% and between 10-19 years of age (36.6%. The risk factors identified in the univariable analysis were water contacts for vegetable extraction (Risk Ratio - RR = 2.92, crossing streams (RR = 2.55, bathing (RR = 2.35, fishing (RR = 2.19, hunting (RR = 2.17, cattle breeding (RR = 2.04, manioc culture (RR = 1.90 and leisure (RR = 1.56. After controlling for confounding variables by proportional hazards model the risks remained higher for males, vegetable extraction, bathing in rivers and water contact in rivers or in periodically inundated parts of riverine woodland (swamplands

  9. Pulmonary leukocytic responses are linked to the acquired immunity of mice vaccinated with irradiated cercariae of Schistosoma mansoni

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    Aitken, R.; Coulson, P.S.; Wilson, R.A.

    1988-05-15

    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.

  10. Histological and histomorphometric evaluation of the retina of mice infected with Schistosoma mansoni in its hepatosplenic form Avaliação histológica e histomorfométrica da retina de camundongos infectados pelo Schistosoma mansoni na forma hepatoesplênica

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    Maria Cecília de Aguiar Remígio; Carlos Teixeira Brandt; Nicodemos Teles de Pontes Filho; Monica Camelo Pessoa de Azevedo Albuquerque

    2009-01-01

    PURPOSE: To evaluate retinal manifestations of Schistosomiasis mansoni in its hepatosplenic form in mice. METHODS: It was performed a study with two groups of mice; one of them was infected with 40 cercariae of Schistosoma mansoni. After 120 days of the infection, the eyes underwent a retinal microscopy study. The histology findings were reported. Histomorphometric analysis was also performed, including: thickness measurement of the retinal layer and the number of the ganglion layer cells. RE...

  11. The prolonged use of niclosamide as a molluscicide for the control of Schistosoma mansoni Uso prolongado da niclosamida como moluscicida para o controle do Schistosoma mansoni

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    Pedro Coura-Filho

    1992-10-01

    Full Text Available Applications of niclosamide at three-monthly intervals were undertaken for 14 years in foci of Biomphalaria glabrata in the water sources of Peri-Peri (Capim Branco, MG. All the residents of the area were submitted to an annual fecal examination (Kato/Katz and those individuals eliminating Schistosoma mansoni eggs were treated with oxamniquine. A malacological survey was undertaken at three-monthly intervals by means of ten scoops with a perforated ladle each ten metres along the two banks of the ditches and streams of the region. Where snails were found, molluscicide was applied by means of dripping or aspersion using a 3 ppm aqueous suspension of niclosamide. Initially, a mean of 14.3% of snails in the region were found to be eliminating cercariae. Following the first four applications of molluscicide, this was reduced to 0.0% and maintained at about 1.5% throughout the program. Thus, there was a continued possibility of schistosomiasis transmission in the area and it was observed that the population of snails reestablished itself within three months of molluscicide application. The results obtained in this study do not encourage the continual use of niclosamide as the only method of control of schistosomiasis.Aplicações trimestrais de niclosamida foram realizadas catorze anos em focos de Biomphalaria glabrata nas coleções hídricas de Peri-Peri, (Capim Branco, MG. Anualmente, os residentes da área eram submetidos a um exame coproscópio (Kato-Katz e os que eliminavam ovos de Schistosoma mansoni nas fezes eram tratados com oxarnniquine. O levantamento malacológico trimestral foi realizado através de dez conchadas a cada dez metros nas duas margens das valas e córregos da região. Onde eram encontrados caramujos aplicava-se o moluscicida pela técnica de gotejamento ou aspersão de suspensão aquosa da niclosamida a 3 ppm. O índice médio de caramujos eliminando cercarias na região era de 14,3%. Após as quatro primeiras aplica

  12. The formin-homology protein SmDia interacts with the Src kinase SmTK and the GTPase SmRho1 in the gonads of Schistosoma mansoni.

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    Thomas Quack

    Full Text Available BACKGROUND: Schistosomiasis (bilharzia is a parasitic disease of worldwide significance affecting human and animals. As schistosome eggs are responsible for pathogenesis, the understanding of processes controlling gonad development might open new perspectives for intervention. The Src-like tyrosine-kinase SmTK3 of Schistosoma mansoni is expressed in the gonads, and its pharmacological inhibition reduces mitogenic activity and egg production in paired females in vitro. Since Src kinases are important signal transduction proteins it is of interest to unravel the signaling cascades SmTK3 is involved in to understand its cellular role in the gonads. METHODOLOGY AND RESULTS: Towards this end we established and screened a yeast two-hybrid (Y2H cDNA library of adult S. mansoni with a bait construct encoding the SH3 (src homology domain and unique site of SmTK3. Among the binding partners found was a diaphanous homolog (SmDia, which was characterized further. SmDia is a single-copy gene transcribed throughout development with a bias towards male transcription. Its deduced amino acid sequence reveals all diaphanous-characteristic functional domains. Binding studies with truncated SmDia clones identified SmTK3 interaction sites demonstrating that maximal binding efficiency depends on the N-terminal part of the FH1 (formin homology domain and the inter-domain region of SmDia located upstream of FH1 in combination with the unique site and the SH3 domain of SmTK3, respectively. SmDia also directly interacted with the GTPase SmRho1 of S. mansoni. In situ hybridization experiments finally demonstrated that SmDia, SmRho1, and SmTK3 are transcribed in the gonads of both genders. CONCLUSION: These data provide first evidence for the existence of two cooperating pathways involving Rho and Src that bridge at SmDia probably organizing cytoskeletal events in the reproductive organs of a parasite, and beyond that in gonads of eukaryotes. Furthermore, the FH1 and inter

  13. Schistosomiasis mansoni of the bladder simulating bladder cancer: a case report Esquistossomose mansônica simulando câncer de bexiga: relato de caso

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    Mário Luis Casella

    2009-10-01

    Full Text Available The relationship between bladder tumors and Schistosoma haematobium is well known, but only sporadic cases of bladder infection due to Schistosoma mansoni have been reported. In this case, a 48-year-old woman with macroscopic hematuria, dysuria and a palpable abdominal mass was investigated. Ultrasound showed a large exophytic mass in the bladder. Transurethral resection of the bladder revealed viable eggs of Schistosoma mansoni. The patient was treated clinically with oxamniquine and surgery was performed to resect the large mass. This case shows that schistosomiasis Mansoni in the bladder can simulate bladder cancer.É bem conhecida a relação entre tumor vesical e Schistosoma haematobium, porém somente casos esporádicos de infecção vesical por Schistosoma mansoni foram relatados. Neste caso, uma mulher de 48 anos com hematúria macroscópica, disúria e massa abdominal palpável foi investigada, ultra-sonografia mostrou uma grande massa exofítica na bexiga. A ressecção transuretral de bexiga evidenciou ovos viáveis de Schistosoma mansoni. A paciente foi tratada clinicamente com oxaminiquine e uma cirurgia foi realizada para ressecar a grande massa. Este caso mostra que a esquistossomose mansônica vesical pode simular um câncer vesical.

  14. Co-infections with Plasmodium falciparum, Schistosoma mansoni and intestinal helminths among schoolchildren in endemic areas of northwestern Tanzania

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    Kweka Eliningaya J

    2010-05-01

    Full Text Available Abstract Background Malaria, schistosomiasis and intestinal helminth infections are causes of high morbidity in most tropical parts of the world. Even though these infections often co-exist, most studies focus on individual diseases. In the present study, we investigated the prevalence of Plasmodium falciparum-malaria, intestinal schistosomiasis, soil-transmitted helminth infections, and the respective co-infections, among schoolchildren in northwest Tanzania. Methods A cross sectional study was conducted among schoolchildren living in villages located close to the shores of Lake Victoria. The Kato Katz technique was employed to screen faecal samples for S. mansoni and soil-transmitted helminth eggs. Giemsa stained thick and thin blood smears were analysed for the presence of malaria parasites. Results Of the 400 children included in the study, 218 (54.5% were infected with a single parasite species, 116 (29% with two or more species, and 66 (16.5% had no infection. The prevalences of P. falciparum and S. mansoni were 13.5% (95% CI, 10.2-16.8, and 64.3% (95% CI, 59.6-68.9 respectively. Prevalence of hookworm infection was 38% (95% CI, 33.2-42.8. A. lumbricoides and T. trichiura were not detected. Of the children 26.5% (95% CI, 21.9-30.6 that harbored two parasite species, combination of S. mansoni and hookworm co-infections was the most common (69%. Prevalence of S. mansoni - P. falciparum co-infections was 22.6% (95%CI, 15.3-31.3 and that of hookworm - P. falciparum co-infections 5.7% (95%CI, 2.6-12.8. Prevalence of co-infection of P. falciparum, S. mansoni and hookworm was 2.8% (95%CI, 1.15-4.4. Conclusion Multiple parasitic infections are common among schoolchildren in rural northwest Tanzania. These findings can be used for the design and implementation of sound intervention strategies to mitigate morbidity and co-morbidity.

  15. Structural basis for the inhibition of histone deacetylase 8 (HDAC8, a key epigenetic player in the blood fluke Schistosoma mansoni.

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    Martin Marek

    Full Text Available The treatment of schistosomiasis, a disease caused by blood flukes parasites of the Schistosoma genus, depends on the intensive use of a single drug, praziquantel, which increases the likelihood of the development of drug-resistant parasite strains and renders the search for new drugs a strategic priority. Currently, inhibitors of human epigenetic enzymes are actively investigated as novel anti-cancer drugs and have the potential to be used as new anti-parasitic agents. Here, we report that Schistosoma mansoni histone deacetylase 8 (smHDAC8, the most expressed class I HDAC isotype in this organism, is a functional acetyl-L-lysine deacetylase that plays an important role in parasite infectivity. The crystal structure of smHDAC8 shows that this enzyme adopts a canonical α/β HDAC fold, with specific solvent exposed loops corresponding to insertions in the schistosome HDAC8 sequence. Importantly, structures of smHDAC8 in complex with generic HDAC inhibitors revealed specific structural changes in the smHDAC8 active site that cannot be accommodated by human HDACs. Using a structure-based approach, we identified several small-molecule inhibitors that build on these specificities. These molecules exhibit an inhibitory effect on smHDAC8 but show reduced affinity for human HDACs. Crucially, we show that a newly identified smHDAC8 inhibitor has the capacity to induce apoptosis and mortality in schistosomes. Taken together, our biological and structural findings define the framework for the rational design of small-molecule inhibitors specifically interfering with schistosome epigenetic mechanisms, and further support an anti-parasitic epigenome targeting strategy to treat neglected diseases caused by eukaryotic pathogens.

  16. Whole-organ isolation approach as a basis for tissue-specific analyses in Schistosoma mansoni.

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    Steffen Hahnel

    Full Text Available BACKGROUND: Schistosomiasis is one of the most important parasitic diseases worldwide, second only to malaria. Schistosomes exhibit an exceptional reproductive biology since the sexual maturation of the female, which includes the differentiation of the reproductive organs, is controlled by pairing. Pathogenicity originates from eggs, which cause severe inflammation in their hosts. Elucidation of processes contributing to female maturation is not only of interest to basic science but also considering novel concepts combating schistosomiasis. METHODOLOGY/PRINCIPAL FINDINGS: To get direct access to the reproductive organs, we established a novel protocol using a combined detergent/protease-treatment removing the tegument and the musculature of adult Schistosoma mansoni. All steps were monitored by scanning electron microscopy (SEM and bright-field microscopy (BF. We focused on the gonads of adult schistosomes and demonstrated that isolated and purified testes and ovaries can be used for morphological and structural studies as well as sources for RNA and protein of sufficient amounts for subsequent analyses such as RT-PCR and immunoblotting. To this end, first exemplary evidence was obtained for tissue-specific transcription within the gonads (axonemal dynein intermediate chain gene SmAxDynIC; aquaporin gene SmAQP as well as for post-transcriptional regulation (SmAQP. CONCLUSIONS/SIGNIFICANCE: The presented method provides a new way of getting access to tissue-specific material of S. mansoni. With regard to many still unanswered questions of schistosome biology, such as elucidating the molecular processes involved in schistosome reproduction, this protocol provides opportunities for, e.g., sub-transcriptomics and sub-proteomics at the organ level. This will promote the characterisation of gene-expression profiles, or more specifically to complete knowledge of signalling pathways contributing to differentiation processes, so discovering involved

  17. QUESTIONNAIRES IN THE SCREENING FOR Schistosoma mansoni INFECTION: A STUDY OF SOCIO DEMOGRAPHIC AND WATER CONTACT VARIABLES IN FOUR COMMUNITIES IN BRAZIL

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    Lima e Costa Maria Fernanda F.

    1998-01-01

    Full Text Available The use of questionnaires has been recommended for identifying, at a lower cost, individuals at risk for schistosomiasis. In this study, validity of information obtained by questionnaire in the screening for Schistosoma mansoni infection was assessed in four communities in the State of Minas Gerais, Brazil. Explanatory variables were water contact activities, sociodemographic characteristics and previous treatment for schistosomiasis. From 677, 1474, 766 and 3290 individuals eligible for stool examination in the communities, 89 to 97% participated in the study. The estimated probability of individuals to be infected, if they have all characteristics identified as independently associated with S.mansoni infection, varied from 15% in Canabrava, to 42% in Belo Horizonte, 48% in Comercinho and 80% in São José do Acácio. Our results do not support the hypothesis that a same questionnaire on risk factors could be used in screening for S.mansoni infection in different communities.

  18. Inhibition of Schistosoma mansoni ether-a-go-go related gene-encoded potassium channels leads to hypermotility and impaired egg production.

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    Parker-Manuel, S J; Hahnel, S; Grevelding, C G

    2015-11-01

    The purpose of this work was to investigate the effect of ether-a-go-go related gene (ERG) potassium channel inhibition on Schistosoma mansoni. Use of dofetilide to block the schistosome ERGs resulted in a striking 'corkscrew' effect. The worms were unable to control their motility; they were hypermotile. The treated worms produced abnormal eggs, some of which consisted of little more than a spine. One of the S. mansoni ERGs (SmERGs), Smp_161140, was chosen for further study by RNAi. The transcript was knocked down to 50% compared to the controls. These RNAi-treated worms demonstrated seizure-like movements. In S. mansoni, as in other organisms, ERG channels seem to play a role in regulating muscle excitability. This work shows that egg production can be greatly reduced by effectively targeting muscle coordination in these important parasites. PMID:26188142

  19. Serodiagnosis of Schistosoma mansoni infections in an endemic area of Burkina Faso: performance of several immunological tests with different parasite antigens.

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    Sorgho, Hermann; Bahgat, Mahmoud; Poda, Jean-Noel; Song, Wenjian; Kirsten, Christa; Doenhoff, Michael J; Zongo, Issaka; Ouédraogo, Jean-Bosco; Ruppel, Andreas

    2005-02-01

    The performance of indirect haemagglutination assays (IHA), enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescent antibody tests (IFAT) were compared with 450 sera from a Schistosoma mansoni-endemic area in Burkina Faso. All participants in this survey provided at least one sample each of stool, urine and serum. From those with an egg-negative Kato-Katz thick smear, a second stool sample was examined. IHA was based on either extracts of adult S. mansoni worms (SmIHA) or S. japonicum egg antigen (SjIHA). For ELISA, three antigen preparations were used, namely: (i) soluble S. mansoni adult worm antigens (SWAP); (ii) soluble S. mansoni egg antigens (SEA); and (iii) a cationic exchange fraction of S. mansoni eggs (CEF6). IFAT was performed with S. mansoni male worm sections. Among the egg-excretors, the sensitivity of ELISA was high and egg antigens performed slightly better (SEA, 96%; CEF6, 97%) than worm antigen (94%). Sensitivity of IHA was satisfactory with homologous (Sm, >85%), but not heterologous (Sj, 56%) parasite antigen. In IFAT, the parenchyma-associated fluorescence showed high sensitivity (95%), but gut-associated fluorescence, which is known to be a sensitive diagnostic marker for schistosome-infected European travelers, was observed only in 76% of a sub-sample of 100 of the endemic sera. Among sera from egg-negative individuals, many gave positive reactions in several or all of the tests employed. These reactions (formally "false positive") are considered to represent true infections, since chemotherapy had not yet been delivered to this population. For the purpose of further surveys in Burkina Faso or other resource-poor settings, we suggest IHA as an accurate diagnostic test and propose to further improve its performance by including egg rather than worm antigens.

  20. Nitric oxide production by Biomphalaria glabrata haemocytes: effects of Schistosoma mansoni ESPs and regulation through the extracellular signal-regulated kinase pathway

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    Kirk Ruth S

    2009-04-01

    Full Text Available Abstract Background Schistosoma mansoni uses Biomphalaria glabrata as an intermediate host during its complex life cycle. In the snail, the parasite initially transforms from a miracidium into a mother sporocyst and during this process excretory-secretory products (ESPs are released. Nitric oxide (NO and its reactive intermediates play an important role in host defence responses against pathogens. This study therefore aimed to determine the effects of S. mansoni ESPs on NO production in defence cells (haemocytes from schistosome-susceptible and schistosome-resistant B. glabrata strains. As S. mansoni ESPs have previously been shown to inhibit extracellular signal-regulated kinase (ERK phosphorylation (activation in haemocytes from susceptible, but not resistant, B. glabrata the regulation of NO output by ERK in these cells was also investigated. Results Haemocytes from resistant snails challenged with S. mansoni ESPs (20 μg/ml over 5 h displayed an increase in NO production that was 3.3 times greater than that observed for unchallenged haemocytes; lower concentrations of ESPs (0.1–10 μg/ml did not significantly increase NO output. In contrast, haemocytes from susceptible snails showed no significant change in NO output following challenge with ESPs at any concentration used (0.1–20 μg/ml. Western blotting revealed that U0126 (1 μM or 10 μM blocked the phosphorylation (activation status of ERK in haemocytes from both snail strains. Inhibition of ERK signalling by U0126 attenuated considerably intracellular NO production in haemocytes from both susceptible and resistant B. glabrata strains, identifying ERK as a key regulator of NO output in these cells. Conclusion S. mansoni ESPs differentially influence intracellular NO levels in susceptible and resistant B. glabrata haemocytes, possibly through modulation of the ERK signalling pathway. Such effects might facilitate survival of S. mansoni in its intermediate host.

  1. Production of Shistosoma mansoni cercariae by Biomphalaria glabrata from a focus in Belo Horizonte, Minas Gerais Produção de cercárias de Schistosoma mansoni por Biomphalaria glabrata de foco em Belo Horizonte, Minas Gerais

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    Cecília Pereira de Souza

    1994-12-01

    Full Text Available The snail density, levels of infection and the monthly production of Schistosoma mansoni cercariae by Biomphalaria glabrata were determined in a focus of Barreiro de Baixo (Belo Horizonte, MG, Brazil. During a period of 38 months (1984 to 1987 5,366 snails were collected of which 324 (6.03% were infected with S. mansoni. The total number of cercariae shed was 5,667,312. Each snail shed an average of 17,422 cercariae during the time that it was under study in the laboratory. The greatest longevity of infected snails was 218 days. Natural cure was observed in 42 (12.9% of the infected specimens about 130 days after collection. The average snail density in the focus during the period of study was 16.3 snails per scoop. The shedding of cercariae by snails collected from the field was compared with laboratory bred specimens infected in mass with the LE strain of S. mansoni from Belo Horizonte. The laboratory infected snails shed an average of 6,061 cercariae each, a value 2.8 times less than the field specimens due to a shorter life span. The prevalence of schistosomiasis in the focus was 14.3%.A densidade planorbídica, as taxas de infecção e a produção mensal de cercárias de Schistosoma mansoni por Biomphalaria glabrata, foram determinadas em foco do Barreiro de Baixo (Belo Horizonte MG, Brasil. Durante 38 meses, de 1984 a 1987, foram capturados 5.366 moluscos dentre os quais 324 (6,03% estavam infectados com o S. mansoni. O total de cercárias eliminadas foi de 5.667.312. Cada molusco eliminou em média 17.422 cercárias durante sua permanência no laboratório. A maior longevidade dos moluscos infectados foi de 218 dias. Foi observada a cura natural de 42 (12,9% dos exemplares infectados, após cerca de 130 dias de captura. A densidade planorbídica média, no foco durante esse período foi de 16,3 moluscos por conchada. A eliminação de cercárias pelos moluscos do campo foi comparada com a de exemplares criados no laboratório, infectados

  2. Resistance of Biomphalaria occidentalis from Varzea das Flores dam, Minas Gerais, to Schistosoma mansoni infection detected by low stringency polymerase chain reaction

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    Cecilia Pereira de Souza

    2001-04-01

    Full Text Available Biomphalaria occidentalis Paraense, 1981 from Varzea das Flores dam, MG, Brazil, was exposed to infection with Schistosoma mansoni. Individual infection was performed with 140 B. occidentalis and 100 B. glabrata snails using LE and SJ strains. Two groups of B. occidentalis were killed after seven day-miracidia exposure to detect S. mansoni DNA, through the low stringency polymerase chain reaction (LS-PCR, and were negative. The infection rates were 69.2% (LE strain and 96.7% (SJ strain for B. glabrata and 0% for B. occidentalis. LS-PCR enabled early resistance diagnosis.

  3. 曼氏血吸虫Sm28GST疫苗研究进展%Advances in the Research of Sm28GST Vaccine of Schistosoma mansoni

    Institute of Scientific and Technical Information of China (English)

    李文桂; 陈雅棠

    2009-01-01

    曼氏血吸虫病(Schistosomiasis mansoni)是由曼氏血吸虫(Schistosoma mansoni,sm)引起的一种严重危害人类健康的人兽共患寄生虫病,主要流行于非洲、拉丁美洲和亚洲的53个国家和地区.本文综述了Sm28GST蛋白分子、DNA疫苗、rSt疫苗以及rBCG疫苗等方面的研究进展.

  4. Accuracy of urine circulating cathodic antigen test for the diagnosis of Schistosoma mansoni in preschool-aged children before and after treatment.

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    Jean T Coulibaly

    Full Text Available BACKGROUND: The Kato-Katz technique is widely used for the diagnosis of Schistosoma mansoni, but shows low sensitivity in light-intensity infections. We assessed the accuracy of a commercially available point-of-care circulating cathodic antigen (POC-CCA cassette test for the diagnosis of S. mansoni in preschool-aged children before and after praziquantel administration. METHODOLOGY: A 3-week longitudinal survey with a treatment intervention was conducted in Azaguié, south Côte d'Ivoire. Overall, 242 preschoolers (age range: 2 months to 5.5 years submitted two stool and two urine samples before praziquantel administration, and 86 individuals were followed-up posttreatment. Stool samples were examined with duplicate Kato-Katz thick smears for S. mansoni. Urine samples were subjected to POC-CCA cassette test for S. mansoni, and a filtration method for S. haematobium diagnosis. PRINCIPAL FINDINGS: Before treatment, the prevalence of S. mansoni, as determined by quadruplicate Kato-Katz, single CCA considering 'trace' as negative (t-, and single CCA with 'trace' as positive (t+, was 23.1%, 34.3% and 64.5%, respectively. Using the combined results (i.e., four Kato-Katz and duplicate CCA(t- as diagnostic 'gold' standard, the sensitivity of a single Kato-Katz, a single CCA(t- or CCA(t+ was 28.3%, 69.7% and 89.1%, respectively. Three weeks posttreatment, the sensitivity of a single Kato-Katz, single CCA(t- and CCA(t+ was 4.0%, 80.0% and 84.0%, respectively. The intensity of the POC-CCA test band reaction was correlated with S. mansoni egg burden (odds ratio = 1.2, p = 0.04. CONCLUSIONS/SIGNIFICANCE: A single POC-CCA cassette test appears to be more sensitive than multiple Kato-Katz thick smears for the diagnosis of S. mansoni in preschool-aged children before and after praziquantel administration. The POC-CCA cassette test can be recommended for the rapid identification of S. mansoni infections before treatment. Additional studies are warranted

  5. Exposure to Hycanthone alters chromatin structure around specific gene functions and specific repeats in Schistosoma mansoni

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    David eRoquis

    2014-07-01

    Full Text Available Schistosoma mansoni is a parasitic plathyhelminth responsible for intestinal schistosomiasis (or bilharziasis, a disease affecting 67 million people worldwide and causing an important economic burden. The schistosomicides hycanthone, and its later proxy oxamniquine, were widely used for treatments in endemic areas during the 20th century. Recently, the mechanism of action, as well as the genetic origin of a stably and Mendelian inherited resistance for both drugs was elucidated in two strains. However, several observations suggested early on that alternative mechanisms might exist, by which resistance could be induced for these two drugs in sensitive lines of schistosomes. This induced resistance appeared rapidly, within the first generation, but was metastable (not stably inherited. Epigenetic inheritance could explain such a phenomenon and we therefore re-analyzed the historical data with our current knowledge of epigenetics. In addition, we performed new experiments such as ChIP-seq on hycanthone treated worms. We found distinct chromatin structure changes between sensitive worms and induced resistant worms from the same strain. No specific pathway was discovered, but genes in which chromatin structure modification were observed are mostly associated with transport and catabolism, which makes sense in the context of the elimination of the drug. Specific differences were observed in the repetitive compartment of the genome. We finally describe what types of experiments are needed to understand the complexity of heritability that can be based on genetic and/or epigenetic mechanisms for drug resistance in schistosomes.

  6. Comparison between morphological and staining characteristics of live and dead eggs of Schistosoma mansoni

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    AK Sarvel

    2006-10-01

    Full Text Available Schistosoma mansoni eggs are classified, according to morphological characteristics, as follows: viable mature and immature eggs; dead mature and immature eggs, shells and granulomas. The scope of this study was to compare the staining characteristics of different morphological types of eggs in the presence of fluorescent labels and vital dyes, aiming at differentiating live and dead eggs. The eggs were obtained from the intestines of infected mice, and put into saline 0.85%. The fluorescent labels were Hoechst 33258 and Acridine Orange + Ethidium Bromide and vital dyes (Trypan Blue 0.4% and Neutral Red 1%. When labelled with the probe Hoechst 33258, some immature eggs, morphologically considered viable, presented fluorescence (a staining characteristic detected only in dead eggs; mature eggs did not present fluorescence, and the other types of dead eggs, morphologically defined, showed fluorescence. As far as Acridine Orange + Ethidium Bromide are concerned, either the eggs considered to be live, or the dead ones, presented staining with green color, and only the hatched and motionless miracidium was stained with an orange color. Trypan Blue was not able to stain the eggs, considered to be dead but only dead miracidia which had emerged out of the shell. Neutral Red stained both live and dead eggs. Only the fluorescent Hoechst 33258 can be considered a useful tool for differentiation between dead and live eggs.

  7. The effects of gamma-irradiation on migration and survival of Schistosoma mansoni schistosomula in mice

    International Nuclear Information System (INIS)

    Infections with irradiated Schistosoma mansoni were established by intramuscular injection of mechanically transformed schistosomula. A dose of 2.3 krad. allowed persistence of a small proportion of worms to adulthood, and of these survivors the majority of the female worms were sexually sterile. However, a small proportion of 2.3 krad.-irradiated females and a larger proportion of similarly irradiated males were capable of pairing successfully with non-irradiated partners. Radiation in the range 2.3 to 10 krad. resulted in slightly reduced peak recoveries from the lungs while 20 krad. resulted in a much reduced and 40 krad. a virtual absence of survival to the lung stage. Increasing doses of radiation in the range 2.3 to 10 krad. resulted in successively fewer parasites reaching the liver. Thus, the major sites of the radiation-induced mortality appeared to be 2.3 krad., mainly in the liver; 4 krad., in the lungs and liver; 10 krad., mainly in the lungs; 20 krad., at the injection site and in the lungs and 40 krad., mainly at the injection site. These infections showed reduced survival following exposure to high doses of radiation compared with the infections, established as percutaneously applied cercariae, which have been reported elsewhere. (author)

  8. Schistosoma mansoni: cambios ultraestructurales durante la transformación del miracidio in vitro

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    Emilia E. Barrios

    2004-04-01

    Full Text Available Ultrastructural changes were assessed during in vitro transformation ofmiracidia (M of Schistosoma mansoni. Morphological characteristics werebased on viability (protonefrigial integrity and uptake of trypan blue dye, larvalsize and degree of differentiation into mother sporocysts (MS during incubationin RPMI-1640 by 30 min followed by 7 days in Hansen medium. Lightmicroscopy showed that M first step of transformation occurs within 30 min,with loss of movement and ciliary epidermal plates. Transformed MS areextended, with worm-like movement and active flame cells; viability was 76% at5 days and 50% at 11 days, and increased three-fold in length reaching 300 µmduring the first 16 days. Transmission Electron Microscopy at 24 h of culturerevealed significant structural changes in tegumental composition anddistribution; free polysomes and microvilli were found in the external layer ofthe tegument. At day 7 the external membrane of MS was thin and interiorgerminative bags were observed, with electron-dense proteic granules. Theprotonefrigial system remained intact at 24 h of culture, constituted by flamecells with 11 pairs of peripheral microtubules. It is concluded that miracidialtransformation in cell-free culture results in surface alteration, and involvesultrastructural changes

  9. Parasitological characteristics of Schistosoma mansoni infection in swiss mice with underlying malnutrition

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    Simões Carla

    2002-01-01

    Full Text Available The effects of a protein-restricted diet (8% protein, 81% carbohydrate and 11% lipids on Schistosoma mansoni infectivity, fecal egg excretion and intestinal egg distribution in Swiss (SW mice were studied. Pregnant mice received a deficient diet from the middle of gestation until delivery. Seven-days-old mice were exposed to 50 cercariae (BH strain, Brazil. Offspring mice had a free access to the deficient diet since lactation until adulthood. The controls were fed with a commercial mice diet. A parasitological examination was performed between six and eight weeks post-infection while both groups were necropsied one week later. Mice on the experimental diet showed a significant loss in body weight. There was no significant difference (p > 0.05 in pre-patent period, kinetics of egg excretion and worm recovery from mice on either diet. Significant differences (p < 0.05 were found concerning to the percentage of deposited eggs in the distal segment of the small intestine from hosts on the experimental diet.Our data suggest that experimental malnutrition induced for a long term has no detrimental effect on the acute schistosomiais infection in SW mice.

  10. 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.

  11. Antischistosomal activity of a calcium channel antagonist on schistosomula and adult Schistosoma mansoni worms

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    Vanessa Silva-Moraes

    2013-08-01

    Full Text Available Current schistosomiasis control strategies are largely based on chemotherapeutic agents and a limited number of drugs are available today. Praziquantel (PZQ is the only drug currently used in schistosomiasis control programs. Unfortunately, this drug shows poor efficacy in patients during the earliest infection phases. The effects of PZQ appear to operate on the voltage-operated Ca2+channels, which are located on the external Schistosoma mansoni membrane. Because some Ca2+channels have dihydropyridine drug class (a class that includes nifedipine sensitivity, an in vitro analysis using a calcium channel antagonist (clinically used for cardiovascular hypertension was performed to determine the antischistosomal effects of nifedipine on schistosomula and adult worm cultures. Nifedipine demonstrated antischistosomal activity against schistosomula and significantly reduced viability at all of the concentrations used alone or in combination with PZQ. In contrast, PZQ did not show significant efficacy when used alone. Adult worms were also affected by nifedipine after a 24 h incubation and exhibited impaired motility, several lesions on the tegument and intense contractility. These data support the idea of Ca2+channels subunits as drug targets and favour alternative therapeutic schemes when drug resistance has been reported. In this paper, strong arguments encouraging drug research are presented, with a focus on exploring schistosomal Ca2+channels.

  12. Simvastatin and artesunate impact the structural organization of adult Schistosoma mansoni in hypercholesterolemic mice.

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    Alencar, Alba Cristina Miranda de Barros; Santos, Thais da Silva; Neves, Renata Heisler; Lopes Torres, Eduardo José; Nogueira-Neto, José Firmino; Machado-Silva, José Roberto

    2016-08-01

    Experimental data have shown that simvastatin and artesunate possess activity against Schistosoma mansoni worms in mice fed standard chow. However, little is known regarding the roles of these drugs in mice fed high-fat chow. We have extended past studies by measuring the effects of these drugs on the structural organization of adult schistosomes in hypercholesterolemic mice. For this purpose, mice were gavaged with either simvastatin or artesunate at nine weeks post-infection and were euthanized by cervical dislocation at two weeks post-treatment. Adult worms were then collected and examined by conventional light microscopy, morphometry and confocal laser scanning microscopy. Plasma total cholesterol and worm reduction rates were significantly increased in mice fed high-fat chow compared with their respective control groups. Simvastatin and artesunate caused changes in the tegument, tubercles, and reproductive system (testicular lobes, vitelline glands and ovarian cells), particularly when administered to mice fed high-fat chow. In particular, the tegument and tubercles were significantly thinner in artesunate-treated worms in mice fed high-fat chow compared with mice fed standard chow. This study thus demonstrated that simvastatin and artesunate have several novel effects on the structural organization of adult worms. Together, these results show, for the first time, that simvastatin and artesunate display antischistosomal activity in hypercholesterolemic mice. PMID:27228897

  13. Anthelmintic Effects of Alkylated Diamines and Amino Alcohols against Schistosoma mansoni

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    Fábio de Souza Fernandes

    2013-01-01

    Full Text Available Polyamines are substances involved in many aspects of cell growth, division, and differentiation. Because of the metabolic differences between host cells and parasite cells, polyamine metabolism has been considered as a potential target for the chemotherapy of parasitic diseases. The aim of this work was to evaluate the schistosomicidal activity of different N-alkylated diamines (3a–3h, amino alcohols (4a–4d, and glycosylated amino alcohols (10a–10d. Compounds were prepared by synthetic methods and submitted to in vitro evaluation against adult worms of Schistosoma mansoni. At 100 μM, 3b, 3e, and 3h as well as 4a, 4b, 4d, 10a, 10b, and 10d resulted in 100% mortality of adult schistosomes. Compound 3d (12.5 to 100 μM caused the death of 100% of both male and female adult schistosomes, while 3f (12.5 to 100 μM resulted in 100% mortality of only male adult worms, whereas no mortality in female worms was observed. Compounds 3d and 3f were also able to reduce viability and decrease production of developed eggs in comparison with the negative control group. Diamines 3d and 3f may represent useful lead compounds for further optimization in order to develop new schistosomicidal agents.

  14. Indirect Effects of Oral Tolerance Inhibit Pulmonary Granulomas to Schistosoma mansoni Eggs

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    Geraldo Magela Azevedo

    2012-01-01

    Full Text Available Parenteral injection of tolerated proteins into orally tolerant mice inhibits the initiation of immunological responses to unrelated proteins and blocks severe chronic inflammatory reactions of immunological origin, such as autoimmune reactions. This inhibitory effect which we have called “indirect effects of oral tolerance” is also known as “bystander suppression.” Herein, we show that i.p. injection of OVA + Al(OH3 minutes before i.v. injection of Schistosoma mansoni eggs into OVA tolerant mice blocked the increase of pulmonary granulomas. In addition, the expression of ICAM-1 in lung parenchyma in areas outside the granulomas of OVA-orally tolerant mice was significantly reduced. However, at day 18 after granuloma induction there was no difference in immunofluorescency intensity to CD3, CD4, F4/80, andα-SMA per granuloma area of tolerant and control groups. Reduction of granulomas by reexposure to orally tolerated proteins was not correlated with a shift in Th-1/Th-2 cytokines in serum or lung tissue extract.

  15. Transcriptional profiling of the oesophageal gland region of male worms of Schistosoma mansoni.

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    Nawaratna, Sujeevi S K; Gobert, Geoffrey N; Willis, Charlene; Chuah, Candy; McManus, Donald P; Jones, Malcolm K

    2014-09-01

    The intestinal tract of schistosomes opens at the mouth and leads into the foregut or oesophageal region that is lined with syncytium continuous with the apical cytoplasm of the tegument. The oesophagus is surrounded by a specialised gland, the oesophageal gland. This gland releases materials into the lumen of the oesophagus and the region is thought to initiate the lysis of erythrocytes and neutralisation of immune effectors of the host. The oesophageal region is present in the early invasive schistosomulum, a stage potentially targetable by anti-schistosome vaccines. We used a 44k oligonucleotide microarray to identify highly up-regulated genes in microdissected frozen sections of the oesophageal gland of male worms of S. mansoni. We show that 122 genes were up-regulated 2-fold or higher in the oesophageal gland compared with a whole male worm tissue control. The enriched genes included several associated with lipid metabolism and transmembrane transport as well as some micro-exon genes. Since the oesophageal gland is important in the initiation of digestion and the fact that it develops early after invasion of the mammalian host, further study of selected highly up-regulated functionally important genes in this tissue may reveal new anti-schistosome intervention targets for schistosomiasis control. PMID:25149559

  16. 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.

  17. 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.

  18. Collagen arrangement in hepatic granuloma in mice infected with Schistosoma mansoni: dependence on fiber radiation centers

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    H.L. Lenzi

    1999-05-01

    Full Text Available The collagen structure of isolated and in situ liver granuloma from Swiss Webster mice infected with Schistosoma mansoni was sequentially and three-dimensionally analyzed during different times of infection (early acute, acute, transitional acute-chronic, and chronic phases by laser scanning confocal microscopy and electron scanning variable vacuum microscopy. The initial granuloma structure is characterized by vascular collagen residues and by anchorage points (or fiber radiation centers, from where collagenous fibers are angularly shed and self-assembled. During the exudative-productive stage, the self-assembly of these fibers minimizes energy and mass through continuous tension and focal compression. The curvature or angles between collagen fibers probably depends on the fibroblastic or myofibroblastic organization of stress fibers. Gradually, the loose unstable lattice of the exudative-productive stage transforms into a highly packed and stable architecture as a result of progressive compactness. The three-dimensional architecture of granulomas provides increased tissue integrity, efficient distribution of soluble compounds and a haptotactic background to the cells.

  19. [Bilharziasis caused by Schistosoma mansoni in a traveler returning from Guinea: failure of serodiagnostic testing].

    Science.gov (United States)

    Raccurt, C P; El Samad, Y; Chouaki, T; Borel, A; Agnamey, P; Totet, A; Schmit, J L

    2007-04-01

    The purpose of this report is to describe a case of febrile hypereosinophilic syndrome in a traveler three weeks after returning from a sightseeing trip to Guinea. Laboratory testing demonstrated an inflammatory response syndrome and hepatic cytolysis. Parasite serology led to suspicion of toxocariasis that was treated using albendazole. Follow-up tests at two months showed the presence of Schistosoma mansoni eggs in stools despite negative standard serodiagnostic testing (hemagglutination). Secondarily Western blot testing of serum samples at one, two and 14 months after returning from Guinea continued to show only protein bands specific to toxocariasis with no bands specific to bilhariziasis. These findings provide further evidence of the limitations of serological testing for detection of bilharziasis in travelers and the difficulty of diagnosis. Guinea is a high-risk tourist destination. Intestinal and urinary bilharziasis are endemic over three-fourths of country. Travelers planning even short stays in areas where bilharziasis is endemic should be advised on preventive measures. PMID:17691438

  20. Activity Profile of an FDA-Approved Compound Library against Schistosoma mansoni.

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    Gordana Panic

    Full Text Available As plans to expand mass drug treatment campaigns to fight schistosomiasis form, worries about reliance on praziquantel as the sole available treatment motivate the investigation for novel antischistosomal compounds. Drug repurposing might be an inexpensive and effective source of novel antischistosomal leads.1600 FDA approved compounds were first assayed against Schistosoma mansoni schistosomula at a concentration of 10 µM. Active compounds identified from this screen were advanced to the adult worm screen at 33.33 µM, followed by hit characterization. Leads with complementary pharmacokinetic and toxicity profiles were then selected for in vivo studies.The in vitro screen identified 121 and 36 compounds active against the schistosomula and adult stage, respectively. Further, in vitro characterization and comparison with already available pharmacokinetic and toxicity data identified 11 in vivo candidates. Doramectin (10 mg/kg and clofazimine (400 mg/kg were found to be active in vivo with worm burden reductions of 60.1% and 82.7%, respectively.The work presented here expands the knowledge of antischistosomal properties of already approved compounds and underscores variations observed between target-based and phenotypic approaches and among laboratories. The two in vivo-active drugs identified in this study, doramectin and clofazimine are widely available and present as novel drug classes as starting points for further investigation.

  1. Schistosoma mansoni polypeptides immunogenic in mice vaccinated with radiation-attenuated cercariae

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    Dalton, J.P.; Strand, M.

    1987-10-01

    We compared the humoral immune response of mice protected against Schistosoma mansoni by vaccination with radiation-attenuated cercariae to that of patently infected mice, and we identified antigens that elicit a greater, or unique, immune response in the vaccinated mice. These comparisons were based upon radioimmunoprecipitations and immunodepletion of (/sup 35/S)methionine-labeled schistosomular and adult worm polypeptides, followed by one- and two-dimensional polyacrylamide gel analyses. The humoral responses of patently infected mice and of mice vaccinated once were remarkably similar and were directed against schistosome glycoproteins ranging in molecular size from greater than 300 to less than 10 kDa. Exposing mice to a second vaccination resulted in a marked change in the immune response, to one predominantly directed toward high molecular size glycoproteins. Sequential immunodepletion techniques identified five schistosomular and seven adult worm antigens that showed a greater or unique immunogenicity in vaccinated mice as compared with patently infected mice. These adult worm antigens were purified by preparative sequential immunoaffinity chromatography and used to prepare a polyclonal antiserum, anti-irradiated vaccine. This antiserum bound to the surface of live newly transformed and lung-stage schistosomula, as assessed by immunofluorescence assays, and was reactive with a number of /sup 125/I-labeled schistosomular surface polypeptides, including a doublet of 150 kDa that was also recognized by sera of vaccinated mice but not by sera of patently infected mice.

  2. Immunity to Schistosoma mansoni in congenitally athymic, irradiated and mast cell-depleted rats

    Energy Technology Data Exchange (ETDEWEB)

    Ford, M.J.; Bickle, Q.D.; Taylor, M.G.

    1987-04-01

    Immunity to Schistosoma mansoni was investigated in congenitally athymic (Nu/Nu) rats, irradiated rats and in mast cell-depleted rats. Nu/Nu rats failed to develop significant resistance following vaccination with irradiated cercariae, although Nu/Nu recipients of serum from vaccinated Fischer rats (VRS) manifested resistance comparable to heterozygous controls, suggesting that T-cells were required in the induction of resistance but were not involved in the efferent arm of antibody-dependent elimination. Radiosensitive cells (including eosinophils, basophils, neutrophils, lymphocytes and mast cells) were apparently not essential for the antibody-dependent elimination of lung or post-lung stages since irradiated (700-750 rad.) recipients of VRS manifested comparable degrees of resistance to unirradiated controls in spite of a greater than 85% reduction in total blood leucocyte counts after irradiation. Depletion of 99% of tissue mast cells by treatment of rats with Compound 48/80 had no significant effect on the attrition of a challenge infection in rats rendered immune by vaccination with irradiated cercariae or by transfer of VRS. However, there was a significant increase in worm recovery in unimmunized and mast cell-depleted or irradiated rats, indicating that mast cells and perhaps other radio-isotope sensitive cells may be involved in innate resistance.

  3. Choline incorporation by Schistosoma mansoni: distribution of choline metabolites during development and after sexual differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Ancelin, M.L.; Torpier, G.; Vial, H.J.; Capron, A.

    1987-06-01

    Choline metabolism was investigated in Schistosoma mansoni during the main phases of its development, namely, schistosomula, 11- and 15-day-old worms, and adults. At the physiological choline concentration used in the assay (20 microM), betaine was, along with phosphatidylcholine, one of the most abundant choline metabolites, revealing considerable choline oxidation activity. Very little radioactivity was associated with CDP-choline, whereas a sustained incorporation into phosphocholine occurred. These results provide good evidence that CTP:phosphocholine cytidylyltransferase plays a regulatory role in the de novo pathway of phosphatidylcholine biosynthesis. During development, the incorporation of choline into its various metabolites was maximal in 11-day-old worms. At this stage, the oxidative pathway predominated over the Kennedy pathway, whereas at all other stages the de novo phosphatidylcholine biosynthesis was predominant. Furthermore, choline incorporation into betaine was much more important in the adult female worm than in the male, indicating a major difference in choline incorporation and distribution between the 2 sexes of the adult worms.

  4. THE SCHISTOSOMULA TEGUMENT ANTIGEN AS A POTENTIAL CANDIDATE FOR THE EARLY SEROLOGICAL DIAGNOSIS OF SCHISTOSOMIASIS MANSONI

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    Rafaella Grenfell

    2013-04-01

    Full Text Available If Schistosoma mansoni infection could be detected in its early stages, especially before the egg deposition in the host tissues, the development of severe pathologic lesions could be efficiently prevented. We therefore developed an indirect enzyme-linked immunosorbent assay based on the detection of specific IgG against schistosomula antigens (ELISA-SmTeg. The assay was applied in sera samples from non-infected and infected mice collected seven and 15 days post-infection. The results were compared to the number of adult worms obtained by perfusion of the murine hepatic system 50 days post-infection. The sensitivity and specificity of the ELISA-SmTeg were 100% (p = 0.0032 and 0.0048 respectively for seven and 15 days of infection with a cutoff value of 0.15 (p = 0.0002. Our findings show a novel low-cost serological assay using antigens which are easy to obtain, which was able to detect all the infected mice as early as seven days post-infection.

  5. Circulating Antigens Levels in Different Clinical Forms of the Schistosoma mansoni Infection

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    Yerkes Pereira e Silva

    1999-01-01

    Full Text Available With the aim to evaluate the circulating cathodic antigen (CCA levels in relation to the different clinical phases of Schistosoma sp. infection a sandwich ELISA using monoclonal antibody 5H11 was performed. The sera of three groups of 25 Brazilian patients with acute, intestinal and hepatosplenic forms of S. mansoni infection were tested and compared to a non-infected control group. Patients and control groups were matched for age and sex and the number of eggs per gram of feces was equally distributed among the three patient groups. Sensitivity of 100%, 72%, 52% of the assay was observed for the intestinal, hepatosplenic and acute toxemic groups respectively. The specificity was 100%. Intestinal and hepatosplenic groups presented CCA levels significantly higher in comparison to those observed for acute patients (F-ratio = 2,524; p = 0.000 and F-ratio = 6,314; p = 0.015 respectively. There was no significant difference of CCA serum levels between hepatosplenic and intestinal groups (F-ratio = 1,026; p = 0.316.

  6. Newly established monoclonal antibody diagnostic assays for Schistosoma mansoni direct detection in areas of low endemicity.

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    Rafaella Fortini Queiroz Grenfell

    Full Text Available BACKGROUND: Current available methods for diagnosis of schistosomiasis mansoni lack sufficient sensitivity, which results in underreporting of infectious in areas of low endemicity. METHODOLOGY/PRINCIPAL FINDINGS: We developed three novel diagnostic methodologies for the direct detection of schistosome infection in serum samples. These three new methods were evaluated with positive patients from a low endemicity area in southeast Brazil. The basis of the assay was the production of monoclonal antibodies against the protein backbone of heavily glycosylated Circulating Cathodic Antigen (CCA. The antibodies were also selected for having no specificity to repeating poly-Lewis x units. Assays based on the detection CCA-protein should not encounter a limitation in sensitivity due to a biological background of this particular epitope. Three diagnostic methodologies were developed and validated, (i Immunomagnetic Separation based on improved incubation steps of non-diluted serum, (ii Direct Enzyme-linked Immunosorbent Assay and (iii Fluorescent Microscopy Analysis as a qualitative assay. The two quantitative assays presented high sensitivity (94% and 92%, respectively and specificity (100%, equivalent to the analysis of 3 stool samples and 16 slides by Kato-Katz, showing promising results on the determination of cure. CONCLUSIONS/SIGNIFICANCE: The Immunomagnetic Separation technique showed excellent correlation with parasite burden by Cohen coefficient. The qualitative method detected 47 positive individuals out of 50 with the analysis of 3 slides. This easy-to-do method was capable of discriminating positive from negative cases, even for patients with low parasite burden.

  7. Factors Involved in Schistosoma mansoni Infection, in Rural Areas of Northeast Brazil

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    Coutinho Eridan M

    1997-01-01

    Full Text Available Two contiguous villages in Tracunhaém county (State of Pernambuco, endemic for schistosomiasis, were studied: Itapinassu (138 inhabitants and São Joaquim (91 inhabitants. Agriculture predominates in the former region while ceramics is the main activity in the latter. Although no statistical difference was found regarding prevalence, severe infection (>400 epg predominated in Itapinassu, probably related to the kind of occupation. No association was found between parasite burden and severity of disease, in spite of the high infection rates for Schistosoma mansoni in both communities (approx. 60%. Typical epidemiological features of schistosomiasis such as age-related prevalences and intensities of infection (high in children, low in adults were also mutual characteristics. Nutritional status determined through anthropometric evaluation was carried out by measuring specific anthropometric indicators. A deficit of energy intake, as well as vitamin A and riboflavin deficiencies were detected. The prevalence of moderate or severe undernutrition in patients under 18 years old was 21.9% in Itapinassu and 24.1% in São Joaquim. In this group an association was found between prevalence of schistosomiasis and chronic undernutrition. Similarly, for patients over 18 year old the prevalence of undernutrition was higher than 20%. However, in this case no association between nutritional status and either prevalence of schistosomiasis or parasite burden could be detected. The two communities had not been treated for eight years.

  8. Development of Schistosoma mansoni worms in mice analyzed by bright field and confocal microscopy

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    Carla de Lamare Biolchini

    2006-10-01

    Full Text Available The blood flukes of mammals (Digenea: Schistosomatidae are among trematodes unique whose adult worms have separeted sexes which are dissimilar in appearance. The developmental features, growth and organogenesis of Schistosoma mansoni were studied in Swiss Webster mice by a digital system for image analysis and confocal microscopy. Data so far obtained showed two phases with significative morphological changes at 3-4 weeks post-infection, and a gradual similar development onwards in the reproductive system and tegument. Our male-dependent phase demonstrated that mating occurs before sexual maturing. At week three, the majority of male worms (59% had formed the gynaecophoric canal although testicular lobes and tegumental tubercles were absent. By this time, 33% females had an incipient ovary (without cellular differentiation. At week four, 77.2% males presented testicular lobes with few germinative cells while 26% had developing tegumental tubercles. The immature ovary was observed in 69% females. Suckers followed different pattern of growth between male and females. The size of oral and ventral suckers from six-week-old male worms grew abruptly (3.0 fold more than that of three-week-old. In female worms, maximum growth was attained at week four, reducing in size thereafter. From sixth week onwards, all specimens showed the fully developed reproductive system. Probably, these features are morphological traits which schistosome has experienced from hermaphrodite to dioecy.

  9. Rapidly boosted Plasma IL-5 induced by treatment of human Schistosomiasis haematobium is dependent on antigen dose, IgE and eosinophils

    DEFF Research Database (Denmark)

    Wilson, Shona; Jones, Frances M.; Fofana, Hassan K. M.;

    2013-01-01

    IgE specific to worm antigen (SWA) and pre-treatment eosinophil number, are associated with human immunity to re-infection with schistosomes after chemotherapeutic treatment. Treatment significantly elevates circulating IL-5 24-hr post-treatment of Schistosoma mansoni. Here we investigate if praz...

  10. Atividade quimioprofilática de sabonetes contendo óleo essencial de frutos de Pterodon pubescens na esquistossomose mansoni Chemoprophylactic activity of soaps containing essential oil of Pterodon pubescens fruits in Schistosomiasis mansoni

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    D. Santos Filho

    1987-01-01

    Full Text Available It has been studied the chemoprophylactic action on experimental schistosomiasis of the essential oil from Pterodon pubescens "sucupira branca" as an additive through different formulations, in toilet soap. Immediately or 24 hours later, groups of mice were exposed by tail method to Schistosoma mansoni cercariae. After 45 days of the exposition, the protective action of these soaps were evaluated. The results showed different levels of protection, ranging from 29.0 to 100.0%. Further studies are on going with the most promising formulations.

  11. 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.

  12. Prevalência da infecção pelo Schistosoma mansoni em dois municípios do Estado de Alagoas Prevalence of Schistosoma mansoni infection in two municipalities of the State of Alagoas, Brazil

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    Danylo César Correia Palmeira

    2010-06-01

    Full Text Available INTRODUÇÃO: Estudos preliminares indicam uma provável expansão da esquistossomose em Alagoas. Este trabalho analisa a ocorrência do Schistosoma mansoni em escolares de dois municípios, localizados nas bacias hidrográficas dos rios Mundaú e Paraíba. MÉTODOS: O grupo de estudo foi constituído por 690 escolares da zona urbana, com idade entre sete e 15 anos. Foram aplicados interrogatórios socioeconômicos e foram usados exames parasitológicos para diagnostico da esquistossomose (métodos de Kato e de Lutz. Foram tratados os casos positivos e foram ministradas palestras para alunos e familiares sobre educação sanitária. RESULTADOS: A prevalência de Schistosoma mansoni foi de 24,9%. A associação entre esquistossomose e outras parasitoses foi significativa em relação à tricuríase (pINTRODUCTION: Preliminary studies indicate a probable schistosomiasis expansion in Alagoas. This work analyzes the occurrence of Schistosoma mansoni in students from two municipalities, located in the Mundaú and Paraíba rivers basins. METHODS: The study group consisted of 690 students in the urban area, aged between seven and 15 years. A standardized socio-economic questionnaire was filled out and parasitological tests were used to diagnosis schistosomiasis (Lutz and Kato methods. Positive cases were treated and students and their families were lectured about health education. RESULTS: The Schistosoma mansoni prevalence was 24.9%. The association between schistosomiasis and other parasitic diseases was significant in relation to trichuriasis (p <0.05. Only 50% of infected children lived in brick homes with sanitation and public water supply. Among them, 48.1% used to go usually to the water collections and 55.8% of them knew rivers snails. The concordance analysis between the Lutz and Kato methods showed disagreement in 54.2%, with greater sensitivity for the Lutz technique (76.4%. CONCLUSIONS: The indices obtained characterize the municipalities

  13. Evaluation of the CCA Immuno-Chromatographic Test to Diagnose Schistosoma mansoni in Minas Gerais State, Brazil.

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    Alda Maria Soares Silveira

    2016-01-01

    Full Text Available The Kato-Katz (KK stool smear is the standard test for the diagnosis of Schistosoma mansoni infection, but suffers from low sensitivity when infections intensities are moderate to low. Thus, misdiagnosed individuals remain untreated and contribute to the disease transmission, thereby forestalling public health efforts to move from a modality of disease control to one of elimination. As an alternative, the urine-based diagnosis of schistosomiasis mansoni via the circulating cathodic antigen immuno-chromatographic test (CCA-ICT has been extensively evaluated in Africa with the conclusion that it may replace the KK test in areas where prevalences are moderate or high.The objective was to measure the performance of the CCA-ICT in a sample study population composed of residents from non-endemic and endemic areas for schistosomiasis mansoni in two municipalities of Minas Gerais state, Brazil. Volunteers (130 were classified into three infection status groups based on duplicate Kato-Katz thick smears from one stool sample (2KK test: 41 negative individuals from non-endemic areas, 41 negative individuals from endemic areas and 48 infected individuals from endemic areas. Infection status was also determined by the CCA-ICT and infection exposure by antibody ELISA (enzyme-linked immunosorbent assay to S. mansoni soluble egg antigen (SEA and soluble (adult worm antigen preparation (SWAP. Sensitivity and specificity were influenced by whether the trace score visually adjudicated in the CCA-ICT was characterized as positive or negative for S. mansoni infection. An analysis of a two-graph receiver operating characteristic was performed to change the cutoff point. When the trace score was interpreted as a positive rather than as a negative result, the specificity decreased from 97.6% to 78.0% whereas sensitivity increased from 68.7% to 85.4%. A significantly positive correlation between the CCA-ICT scores and egg counts was identified (r = 0.6252, p = 0

  14. Melatonin and schistosomal antigens ameliorate the anti-oxidative and biochemical response to Schistosoma mansoni infection in hamster

    Institute of Scientific and Technical Information of China (English)

    Nahla S.El-SHENAWY; Maha F.M.SOLIMAN; Shimaa E.Abel-RAHMAN

    2009-01-01

    The present study was designed to investigate the potential protective effect of melatonin as an antioxidant separately or in combination with antigens (cercarial; CAP or soluble worm; SWAP) against Schistosoma mansoni infection in hamsters. Each hamster was sensitized with an initial immunization of 0.6 ml of the extracted antigen (30 μg protein/mL). After four days, a second injection of 0.4 mL was given (20 μg protein/mL). Then, each hamster was exposed to 260±20 S.mansoni cercariae followed with melatonin treatment (3.5 mg/kg) for thirty days from the 1st day of post infection. Levels of lipid peroxidation (LPO) products, catalase (CAT) activity, hepatic glutathione (GSH) and biochemical changes in the liver and kidneys functions were investigated. The results revealed a high significant increasing of LPO and decreasing of CAT and GSH in liver of infected hamsters. Biochemical observations showed severe damage in the liver enzyme activities and increasing cholesterol level in infected animals. Melatonin co-treatment with antigen to the infected-hamster attenuated the increase of LPO and restored the activity of CAT and levels of hepatic GSH. Also, the biochemical damages in the liver and kidneys functions were reduced. The present study suggests that melatonin may be useful in combating free radical-induced damage due to infection toxicity. The immunization with previous antigens resulted in a remarkable improvement on the liver enzyme activities, which were increased after infection. Thus, vaccination of hamsters with antigens (both CAP and SWAP) and melatonin treatment has more potent effect on the enhancement of antioxidant and biochemical of S.mansoni infected-hamster than each treatment separately. Immunization of the hamster with SWAP followed by melatonin was the best way among the other regime treatments to improve the biochemical and antioxidant parameters of the infected-hamsters[Current Zoology 55(2):165-172,2009].

  15. Carbohydrate metabolism alterations in Biomphalaria glabrata infected with Schistosoma mansoni and exposed to Euphorbia splendens var. hislopii latex

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    Clélia Christina Mello-Silva

    2010-07-01

    Full Text Available This paper evaluates the alterations in the glycogen content of tissues (digestive gland and cephalopedal mass and glucose in the haemolymph of Biomphalaria glabrata BH strain infected with Schistosoma mansoni BH strain and exposed to the latex of Euphorbia splendens var. hislopii. A reduction in the glycogen deposits was observed in infected snails exposed and not exposed to latex. However, the exposure to latex caused a greater depletion of the glycogen levels in both sites analysed, especially from the third week onward. The utilisation of latex as a molluscicide to control the population of infected B. glabrata selectively is proposed.

  16. Dot-ELISA for the detection of IgM and IgG antibodies to Schistosoma mansoni worm and egg antigens, associated with egg excretion by patients DOT-ELISA para a detecção de anticorpos IgG e IgM para antígenos de ovos e vermes de Schistosoma mansoni, em associação com excreção de ovos por pacientes

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    Pedro Luiz Silva Pinto

    1995-04-01

    Full Text Available Human schistosomiasis, caused by Schistosoma mansoni, is highly prevalent in Brazil and usually diagnosed by time consuming stool analysis. Serological tests are of limited use in this disease, mainly for epidemiological studies, showing no discrimination between previous contact with the parasite and active infections. In the present study, we standardized and compared a Dot-ELISA for IgM and IgG antibodies against S. mansoni antigens from eggs and worms with a routine IgG and IgM immunofluorescence assay using similar antigens, in the study of sera from 27 patients who had quantified egg stool excretion. The positivity obtained for IgG Dot-ELISA was 96.3% and 88.9% for IgM Dot-ELISA with worm antigen and 92.6% and 90.9% with egg antigen. The IFI presented similar positivities using worm antigen, 92.6% (IgG and 96.3% (IgM,and lower results with egg antigen, 77.8% (IgG and IgM. The patients studied were divided into two groups according to their egg excretion, with greater positivity of serological tests in higher egg excreters. When comparing the quantitative egg excretion and the serological titers of the patients, we detected a correlation only with IgM Dot-ELISA, with r=0.552 (p=0.0127. These data show that Dot-ELISA can be used for the detection of specific antibodies against S. mansoni in sera from suspected patients or in epidemiological studies and, with further purification of egg antigen and larger samples, IgM Dot-ELISA could be a possible tool for rough estimates of parasite burden in epidemiological studies.A esquistosomose humana, causada pelo Schistosoma mansoni, é altamente prevalente no Brasil e é usualmente diagnosticada através de exames de fezes, que são demorados. Os testes sorológicos nesta doença limitam-se aos estudos epidemiológicos, mostrando apenas o contato prévio com o parasita e não a infecção realmente ativa. Neste trabalho, nós padronizamos e comparamos um novo ensaio de Dot-ELISA, para detecção de

  17. HIV-1 vaccine-specific responses induced by Listeria vector vaccines are maintained in mice subsequently infected with a model helminth parasite, Schistosoma mansoni.

    Science.gov (United States)

    Shollenberger, Lisa M; Bui, Cac T; Paterson, Yvonne; Nyhoff, Lindsay; Harn, Donald A

    2013-11-19

    In areas co-endemic for helminth parasites and HIV/AIDS, infants are often administered vaccines prior to infection with immune modulatory helminth parasites. Systemic Th2 biasing and immune suppression caused by helminth infection reduces cell-mediated responses to vaccines such as tetanus toxoid and BCG. Therefore, we asked if infection with helminthes post-vaccination, alters already established vaccine induced immune responses. In our model, mice are vaccinated against HIV-1 Gag using a Listeria vaccine vector (Lm-Gag) in a prime-boost manner, then infected with the human helminth parasite Schistosoma mansoni. This allows us to determine if established vaccine responses are maintained or altered after helminth infection. Our second objective asked if helminth infection post-vaccination alters the recipient's ability to respond to a second boost. Here we compared responses between uninfected mice, schistosome infected mice, and infected mice that were given an anthelminthic, which occurred coincident with the boost or four weeks prior, as well as comparing to un-boosted mice. We report that HIV-1 vaccine-specific responses generated by Listeria vector HIV-1 vaccines are maintained following subsequent chronic schistosome infection, providing further evidence that Listeria vector vaccines induce potent vaccine-specific responses that can withstand helminth infection. We also were able to demonstrate that administration of a second Listeria boost, which markedly enhanced the immune response, was minimally impacted by schistosome infection, or anthelminthic therapy. Surprisingly, we also observed enhanced antibody responses to HIV Gag in vaccinated mice subsequently infected with schistosomes.

  18. 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.

  19. 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.

  20. Comparison of purified 12 kDa and recombinant 15 kDa Fasciola hepatica antigens related to a Schistosoma mansoni fatty acid binding protein

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    George V. Hillyer

    1995-04-01

    Full Text Available Vaccines in schistosomiasis using homologous antigens have been studied extensively in experimentally infected mammalian hosts. Vaccines using heterologous antigens have received comparatively less attention. This review summarizes recent work on a heterologous 12 kDa Fasciola hepatica antigenic polypeptide which cross reacts with Schistosoma mansoni. A cDNA has been cloned and sequenced, and the predicted amino acid sequence of the recombinant protein has been shown to have significant (44 identity with a 14 kDa S. mansoni fatty acid binding protein. Thus in the parasitic trematodes fatty acid binding proteins may be potential vaccine candidates. The F. hepatica recombinant protein has been overexpressed and purified and denoted rFh15. Preliminary rFh15 migrates more slowly (i.e. may be slightly larger than nFh12 on SDS-PAGE and has a predicted pI of 6.01 vs. observed pI of 5.45. Mice infected with F. hepatica develop antibodies to nFh12 by 2 weeks of infection vs. 6 weeks of infection to rFh15; on the other hand, mice with schistosomiasis mansoni develop antibodies to both nFh12 and rFh15 by 6 weeks of infection. Both the F. hepatica and S. mansoni cross-reactive antigens may be cross-protective antigens with the protection inducing capability against both species.

  1. Induction of protective immunity against Schistosoma mansoni infection by antigens purified from PIII, a fraction of adult worm, associated to the downregulation of granuloma formation

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    Gustavson Shauma

    1998-01-01

    Full Text Available This study was performed in order to define Schistosoma mansoni antigens able to function as modulator agents in BALB/c mice granulomatous hypersensitivity to parasite egg. The antigens P-24, P-35 and P-97 were purified by affinity chromatography from a fraction of S. mansoni adult worm antigenic preparation, denominated PIII, involved in the inhibition of granulomatous response to eggs. Immunization of mice with these antigens, in the presence of Corynebacterium parvum and Al(OH3 as adjuvant, induced a significant protection degree against challenge infection, as observed by the decrease on worm burden recovered from portal system. In vitro blastogenesis assays revealed that purified antigens were able to induce significant proliferation of spleen cells from S. mansoni-infected mice. This protection was correlated to significant decrease in granuloma size induced by PIII. From these results, we concluded that PIII preparation contains antigens capable of mediating protective anti-parasite immunity and down-regulating granulomatous hypersensitivity to S. mansoni eggs.

  2. Effects of Plagiorchis elegans (Digenea: Plagiorchiidae) infection of Biomphalaria glabrata (Pulmonata: Planorbidae) on a challenge infection with Schistosoma mansoni (Digenea: Schistosomatidae).

    Science.gov (United States)

    Zakikhani, M; Smith, J M; Rau, M E

    2003-02-01

    Prior exposure of Biomphalaria glabrata to the eggs of an incompatible digenean, Plagiorchis elegans, rendered this snail host less suitable to a compatible species, Schistosoma mansoni. Although P. elegans failed to develop patent infections in B. glabrata, it reduced the production of S. mansoni cercariae by 88%. Concomitantly, host attributes such as reproduction, growth, and survival were compromised. The effect of P. elegans infection was most severe among snails that, in addition, had developed patent schistosome infections. Although few S. mansoni cercariae were produced, egg production by B. glabrata was only 4% of control values. Furthermore, no doubly infected snails survived for more than 3 wk after patency, whereas controls experienced no mortality during the same time period. The above effects were attributable to the establishment and persistence of P. elegans sporocysts in the tissues of the incompatible snail host. Their indirect antagonistic interaction with thelarval stages of S. mansoni may be mediated, in part, through their long-term stimulation of the host's internal defense mechanisms. These findings are discussed with a view to use P. elegans and other plagiorchiid digeneans as agents in the biological control of snails and snail-borne diseases. PMID:12659305

  3. Schistosoma mansoni and Schistosoma haematobium infection and morbidity in a co-endemic focus : Integrated study of epidemiological, micro-geographical and immunological patterns

    NARCIS (Netherlands)

    Meurs, Lynn

    2014-01-01

    In Africa, polyparasitism is the rule rather than the exception. The aim of this thesis was to get a detailed insight into the micro-geographical distribution and patterns of S. mansoni and S. haematobium co-infections, and how this affects host morbidity. A community-wide study was carried out in a

  4. Single versus double dose praziquantel comparison on efficacy and Schistosoma mansoni re-infection in preschool-age children in Uganda

    DEFF Research Database (Denmark)

    Nalugwa, Allen; Nuwaha, Fred; Tukahebwa, Edridah Muheki;

    2015-01-01

    treatments was assessed and compared 1 month after the second treatment. Re-infection with S. mansoni was assessed in the same children 8 months following the second treatment. CRs were non-significantly higher in children treated with two 40 mg/kg PZQ doses (85.5%; 290/339) compared to a single dose (83...

  5. Efficiency of Immunization of Mice with Irradiated Antigen Against Schistosoma mansoni Infection in Comparison with Praziquantel

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    Mona A. El-Gawish, Manar N. Hafez, Fatma A. Eid* Maha G. Soliman*

    2006-12-01

    Full Text Available Introduction: The present study is an attempt to evaluate the protective effect of schistosomula antigen and the current antischistosomal drug praziquantel (PZQ as a reference drug on mice infected with S. mansoni. Material and Methods: Mice were vaccinated by irradiated or non-irradiated schistosomula antigen, both at a dose of 100 ug protein/mice once weekly for 3 weeks, before infection with alive cercariae and compared with the treatment with i.m. injection of praziquantel at a dose of 40 mg/kg b.wt. 4 times once weekly for 4 weeks after infection. The degree of resistance or protection induced by immunization and chemotherapy was assessed 45 days post­infection and evaluated by physiological, parasitological, immunological as well as histological parameters. Results: The results indicated that immunization with -irradiated antigen at 20 Krad or the treatment with PZQ resulted in significant reduction in ova count in liver and intestine tissues more than those vaccinated with non-irradiated antigen compared with infected group. Immunized group with irradiated antigen and the group treated with PZQ showed a significant decrease in liver enzymes activity (ALT, AST and -GT, while in immunized group with non-irradiated antigen, there was a significant increase in AST and -GT as compared to infected group. The level of alkaline phosphatase enzyme was significantly increased in all investigated groups compared to infected one. Treatment with PZQ or immunization with irradiated or non-irradiated schistosomula antigen induced amelioration in serum IL-10 and TNF-. Scanning electron microscope demonstrated normal mature worms in infected group after 45 days from infection. In contrast, many changes were detected in the rest groups as alterations in the tegument, implosion of tubercles which appeared pealed and sloughed off and most of the spines were detached and separated. Histological examination of liver sections of infected mice revealed lobular

  6. Decay of antibody isotypes against early developmental stages of Schistosoma mansoni after treatment of schistosomiasis patients

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    Herminia Yohko KANAMURA

    1997-09-01

    Full Text Available Antibodies to a number of parasite antigens are found in schistosomiasis patients, and antibodies to early developmental stages were demonstrated to be efficient immunologic markers for the diagnosis of schistosomiasis. In the present study, decay patterns of IgM and IgG antibodies against cercariae and schistosomula were investigated, in comparison to antibodies against worms and eggs in schistosomiasis patients after chemotherapy, for an investigation of seroepidemiologic aspects. Data obtained in the study of 359 serum samples from patients with Schistosoma mansoni infection, noninfected individuals, and patients followed-up for a period of 12 to 15 months after treatment provided the basis to postulate a general pattern for the kinetics of antibody decay. Before treatment, the antibody pattern was represented by a unimodal curve, which shifted to a bimodal curve after treatment, and ended with a unimodal curve similar to that for the noninfected group. Different types of antibodies were classified into four categories according to their decay features, and anti-schistosomulum IgM was classified into the moderate-decay caterogy, whereas other antibodies to early parasite stages were classified into the slow-decay category. The present methodology permits the identification of the most suitable antibodies to be detected in field control programs for schistosomiasis or other parasitosesEm pacientes com esquistossomose, são encontrados anticorpos contra grande número de antígenos parasitários, e aqueles contra formas evolutivas jovens do parasita demonstraram que eram eficientes marcadores imunológicos para o diagnóstico da esquistossomose. Padrões de queda de anticorpos IgM e IgG contra cercária e esquistossômulo foram aqui estudados, comparativamente aos dos anticorpos contra verme e ovo, em pacientes esquistossomóticos após quimioterapia, abordando aspectos soroepidemiológicos. Dados obtidos no estudo de 359 amostras de soros

  7. Suscetibilidade de biomphalaria glabrata, B. straminea e B. tenagophila a diferentes cepas de schistosoma mansoni

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    Luiz Candido de Souza Dias

    1987-08-01

    Full Text Available Em condições experimentais foi estudada a suscetibilidade de Biomphalaria glabrata, B. straminea e B. tenagophila a quatro linhagens humanas (MAP, PTH, UPH, e OuH e duas de roedores silvestres (PTR e VPR do Schistosoma mansoni. Grupos de 50 moluscos foram expostos individualmente a 10 miracídios e observados durante 70 dias. Avaliou-se a suscetibilidade dos moluscos ao parasito por meio da % de animais com esporocistos, % de moluscos que eliminavam cercárias e mortalidade conjunta dos animais expostos e infectados. Exemplares de B. glabrata mineira infectaram-se com cepa simpátrica (MAP e com 5 alopátricas do Estado de São Paulo (PTH, VPH, OuH, PTR e VPR. B. glabrata paulista mostrou altas taxas de infecção com as cepas MAP, VPR e OuH do trematódeo. Quatro % dos exemplares B. straminea de São Paulo eliminavam cercárias de cepas simpátricas; com cepa mineira apenas 4% apresentaram esporocistos na vigência de 20 miracídios por molusco; as menores taxas de mortalidade foram registradas com essa espécie de molusco, não sendo maior do que 20%. B. tenagophila paulista foi suscetível apenas às linhagens simpáticas sendo 6% a maior taxa de moluscos que eliminaram cercárias. Os resultados indicam que os movimentos populacionais humanos dentro do território paulista e para fora dele são importantes na disseminação da esquistossomose mansônica.

  8. Anthelmintic activity in vivo of epiisopiloturine against juvenile and adult worms of Schistosoma mansoni.

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    Maria A Guimarães

    2015-03-01

    Full Text Available Schistosomiasis is a serious disease currently estimated to affect more that 207 million people worldwide. Due to the intensive use of praziquantel, there is increasing concern about the development of drug-resistant strains. Therefore, it is necessary to search for and investigate new potential schistosomicidal compounds. This work reports the in vivo effect of the alkaloid epiisopiloturine (EPI against adults and juvenile worms of Schistosoma mansoni. EPI was first purified its thermal behavior and theoretical solubility parameters charaterised. In the experiment, mice were treated with EPI over the 21 days post-infection with the doses of 40 and 200 mg/kg, and 45 days post-infection with single doses of 40, 100 and 300 mg/kg. The treatment with EPI at 40 mg/kg was more effective in adult worms when compared with doses of 100 and 300 mg/kg. The treatment with 40 mg/kg in adult worms reduced parasite burden significantly, lead to reduction in hepatosplenomegaly, reduced the egg burden in faeces, and decreased granuloma diameter. Scanning electron microscopy revealed morphological changes to the parasite tegument after treatment, including the loss of important features. Additionally, the in vivo treatment against juvenile with 40 mg/kg showed a reduction of the total worm burden of 50.2%. Histopathological studies were performed on liver, spleen, lung, kidney and brain and EPI was shown to have a DL50 of 8000 mg/kg. Therefore EPI shows potential to be used in schistosomiasis treatment. This is the first time that schistosomicidal in vivo activity of EPI has been reported.

  9. Ligation of RNA Oligomers by the Schistosoma mansoni Hammerhead Ribozyme in Frozen Solution.

    Science.gov (United States)

    Lie, Lively; Biliya, Shweta; Vannberg, Fredrik; Wartell, Roger M

    2016-03-01

    The interstitial liquid phase within frozen aqueous solutions is an environment that minimizes RNA degradation and facilitates reactions that may have relevance to the RNA World hypothesis. Previous work has shown that frozen solutions support condensation of activated nucleotides into RNA oligomers, RNA ligation by the hairpin ribozyme, and RNA synthesis by a RNA polymerase ribozyme. In the current study, we examined the activity of a hammerhead ribozyme (HHR) in frozen solution. The Schistosoma mansoni hammerhead ribozyme, which predominantly cleaves RNA, can ligate its cleaved products (P1 and P2) with yields up to ~23 % in single turnover experiments at 25 °C in the presence of Mg(2+). Our studies show that this HHR ligates RNA oligomers in frozen solution in the absence of divalent cations. Citrate and other anions that exhibit strong ion-water affinity enhanced ligation. Yields up to 43 % were observed in one freeze-thaw cycle and a maximum of 60 % was obtained after several freeze-thaw cycles using wild-type P1 and P2. Truncated and mutated P1 substrates were ligated to P2 with yields of 14-24 % in one freeze-thaw cycle. A pool of P2 substrates with mixtures of all four bases at five positions were ligated with P1 in frozen solution. High-throughput sequencing indicated that 70 of the 1024 possible P2 sequences were represented in ligated products at 1000 or more read counts per million reads. The results indicate that the HHR can ligate a range of short RNA oligomers into an ensemble of diverse sequences in ice.

  10. Toxicity of cadmium to Schistosoma mansoni cercariae: effects on vitality and developmental ability in white mice

    Energy Technology Data Exchange (ETDEWEB)

    Holliman, R.B. (Virginia Polytechnic Inst. and State Univ., Blacksburg); Esham, L.P.

    1977-09-29

    Time-until-death studies were run on cercariae of Schistosoma mansoni in 8 concentrations of cadmium (from cadmium sulfate) ranging from 100 ppM to 0.0001 ppM. All concentrations used were found to be toxic, and at 10 ppM all cercariae were dead within 4 hours, which coincides with their period of maximum infectability following emergence from the snail host. At 2 ppM, all cercariae died within 8 hours, and at 1 ppM all died within 16 hours. In addition, groups of cercariae were exposed to cadmium concentrations of 10, 1, and 0.1 ppM for periods of 30, 20, and 10 minutes. Thereafter, cercariae from these groups were allowed to penetrate the tails of white mice or were injected subcutaneously into mice. After 8 weeks, these mice were autopsied and the adult worms collected by perfusion. Maturation of cercariae from both methods of invasion was seriously impaired. Statistical analysis using a 3 x 4 x 2 factoral design for analysis of variance showed both time of exposure and concentration of cadmium ion to be significant factors in determining number of worms developing at p = 0.01. A significant interaction between time of exposure and concentration was found to exist. The two methods of infection did not have a significant effect on the number of worms recovered. Therefore, it appears that those toxicant-exposed cercariae capable of maturing do not need assistance in transversing the skin barrier but can penetrate and migrate to reach the mesenteric venules for maturation.

  11. Antischistosomal activity of ginger (Zingiber officinale) against Schistosoma mansoni harbored in C57 mice.

    Science.gov (United States)

    Mostafa, Osama M S; Eid, Refaat A; Adly, Mohamed A

    2011-08-01

    The repeated chemotherapy of schistosomiasis has resulted in the emergence of drug-resistant schistosome strains. The development of such resistance has drawn the attention of many authors to alternative drugs. Many medicinal plants were studied to investigate their antischistosomal potency. The present work aimed to evaluate antischistosomal activity of crude aqueous extract of ginger against Schistosoma mansoni. Sixteen mice of C57 strain were exposed to 100 ± 10 cercariae per mouse by the tail immersion method; the mice were divided into two groups: untreated group and ginger-treated one. All mice were sacrificed at the end of 10th week post-infection. Worm recovery and egg counting in the hepatic tissues and faeces were determined. Surface topography of the recovered worms was studied by scanning electron microscopy. Histopathological examination of liver and intestine was done using routine histological procedures. The worm burden and the egg density in liver and faeces of mice treated with ginger were fewer than in non-treated ones. Scanning electron microscopical examination revealed that male worms recovered from mice treated with ginger lost their normal surface architecture, since its surface showed partial loss of tubercles' spines, extensive erosion in inter-tubercle tegumental regions and numerous small blebs around tubercles. Histopathological data indicated a reduction in the number and size of granulomatous inflammatory infiltrations in the liver and intestine of treated mice compared to non-treated mice. The results of the present work suggested that ginger has antischistosomal activities and provided a basis for subsequent experimental and clinical trials.

  12. Anthelmintic activity in vivo of epiisopiloturine against juvenile and adult worms of Schistosoma mansoni.

    Science.gov (United States)

    Guimarães, Maria A; de Oliveira, Rosimeire N; Véras, Leiz M C; Lima, David F; Campelo, Yuri D M; Campos, Stefano Augusto; Kuckelhaus, Selma A S; Pinto, Pedro L S; Eaton, Peter; Mafud, Ana C; Mascarenhas, Yvonne P; Allegretti, Silmara M; de Moraes, Josué; Lolić, Aleksandar; Verbić, Tatjana; Leite, José Roberto S A

    2015-03-01

    Schistosomiasis is a serious disease currently estimated to affect more that 207 million people worldwide. Due to the intensive use of praziquantel, there is increasing concern about the development of drug-resistant strains. Therefore, it is necessary to search for and investigate new potential schistosomicidal compounds. This work reports the in vivo effect of the alkaloid epiisopiloturine (EPI) against adults and juvenile worms of Schistosoma mansoni. EPI was first purified its thermal behavior and theoretical solubility parameters charaterised. In the experiment, mice were treated with EPI over the 21 days post-infection with the doses of 40 and 200 mg/kg, and 45 days post-infection with single doses of 40, 100 and 300 mg/kg. The treatment with EPI at 40 mg/kg was more effective in adult worms when compared with doses of 100 and 300 mg/kg. The treatment with 40 mg/kg in adult worms reduced parasite burden significantly, lead to reduction in hepatosplenomegaly, reduced the egg burden in faeces, and decreased granuloma diameter. Scanning electron microscopy revealed morphological changes to the parasite tegument after treatment, including the loss of important features. Additionally, the in vivo treatment against juvenile with 40 mg/kg showed a reduction of the total worm burden of 50.2%. Histopathological studies were performed on liver, spleen, lung, kidney and brain and EPI was shown to have a DL50 of 8000 mg/kg. Therefore EPI shows potential to be used in schistosomiasis treatment. This is the first time that schistosomicidal in vivo activity of EPI has been reported.

  13. Prolyl Oligopeptidase from the Blood Fluke Schistosoma mansoni: From Functional Analysis to Anti-schistosomal Inhibitors.

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    Pavla Fajtová

    Full Text Available Blood flukes of the genus Schistosoma cause schistosomiasis, a parasitic disease that infects over 240 million people worldwide, and for which there is a need to identify new targets for chemotherapeutic interventions. Our research is focused on Schistosoma mansoni prolyl oligopeptidase (SmPOP from the serine peptidase family S9, which has not been investigated in detail in trematodes.We demonstrate that SmPOP is expressed in adult worms and schistosomula in an enzymatically active form. By immunofluorescence microscopy, SmPOP is localized in the tegument and parenchyma of both developmental stages. Recombinant SmPOP was produced in Escherichia coli and its active site specificity investigated using synthetic substrate and inhibitor libraries, and by homology modeling. SmPOP is a true oligopeptidase that hydrolyzes peptide (but not protein substrates with a strict specificity for Pro at P1. The inhibition profile is analogous to those for mammalian POPs. Both the recombinant enzyme and live worms cleave host vasoregulatory, proline-containing hormones such as angiotensin I and bradykinin. Finally, we designed nanomolar inhibitors of SmPOP that induce deleterious phenotypes in cultured schistosomes.We provide the first localization and functional analysis of SmPOP together with chemical tools for measuring its activity. We briefly discuss the notion that SmPOP, operating at the host-parasite interface to cleave host bioactive peptides, may contribute to the survival of the parasite. If substantiated, SmPOP could be a new target for the development of anti-schistosomal drugs.

  14. Schistosoma mansoni-mediated suppression of allergic airway inflammation requires patency and Foxp3+ Treg cells.

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    Laura E Layland

    Full Text Available The continual rise of asthma in industrialised countries stands in strong contrast to the situation in developing lands. According to the modified Hygiene Hypothesis, helminths play a major role in suppressing bystander immune responses to allergens, and both epidemiological and experimental studies suggest that the tropical parasitic trematode Schistosoma mansoni elicits such effects. The focus of this study was to investigate which developmental stages of schistosome infection confer suppression of allergic airway inflammation (AAI using ovalbumin (OVA as a model allergen. Moreover, we assessed the functional role and localization of infection-induced CD4(+Foxp3(+ regulatory T cells (Treg in mediating such suppressive effects. Therefore, AAI was elicited using OVA/adjuvant sensitizations with subsequent OVA aerosolic challenge and was induced during various stages of infection, as well as after successful anti-helminthic treatment with praziquantel. The role of Treg was determined by specifically depleting Treg in a genetically modified mouse model (DEREG during schistosome infection. Alterations in AAI were determined by cell infiltration levels into the bronchial system, OVA-specific IgE and Th2 type responses, airway hyper-sensitivity and lung pathology. Our results demonstrate that schistosome infection leads to a suppression of OVA-induced AAI when mice are challenged during the patent phase of infection: production of eggs by fecund female worms. Moreover, this ameliorating effect does not persist after anti-helminthic treatment, and depletion of Treg reverts suppression, resulting in aggravated AAI responses. This is most likely due to a delayed reconstitution of Treg in infected-depleted animals which have strong ongoing immune responses. In summary, we conclude that schistosome-mediated suppression of AAI requires the presence of viable eggs and infection-driven Treg cells. These data provide evidence that helminth derived products

  15. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    Science.gov (United States)

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina. PMID:25867917

  16. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    Science.gov (United States)

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina.

  17. The use of microencapsulated hepatocytes transplantation reduces mortality and liver alterations in Schistosoma mansoni infected hamsters.

    Science.gov (United States)

    Sherif, Soad A; Moharib, Mona N; El-Lakkany, Naglaa M; Hammam, Olfat A; Salman, Fatma H; El-Naggar, Mohamed M

    2014-04-01

    Hepatocyte transplantation is an attractive therapeutic modality for liver disease as an alternative for orthotropic liver transplantation. The goal of this work was to study the adequacy of intrasplenic hepatocyte transplantation (HCTx) in fresh and microencapsulated forms, in a hamster model of liver fibrosis by Schistosoma mansoni infected hamsters were divided into 6 groups; untreated for 11 weeks (GI) and for 15 weeks (GII), treated with praziquantel (PZQ) 7 weeks PI, and killed 4 weeks (GIII) and 8 weeks (GIV) post-treatment. Treated with PZQ 7 weeks PI, and then treated orally with immunosuppressive drug "cyclosporine (4 weeks post PZQ treatment), 24 hr. before interasplenic injection with fresh hepatocytes (V). Treated with PZQ 7 weeks PI, and then injected interasplenically (4 weeks post-treatment) with microencapsulated hepatocytes (GVI). GI & GIII were killed 11 weeks PI for assessment the anti-schistosomal efficacy of PZQ. The other four groups were killed 15 weeks PI for investigation of liver and spleen histology, serum liver enzymes and hepatic oxidative markers before and after HCTx. Freshly isolated hepatocytes with a mean viability 92.97 +/- 1.2% were used for microencapsulation and transplantation. Histological study showed the presence of transplanted hepatocytes in spleen of recipient. PZQ accelerated healing of hepatic granulomatous lesions as evidenced parasitologically by the increase in the percentage of dead eggs and histologically showing more granuloma circumscription with more ova degeneration and less inflammatory cells. The 25-day survival rates in GII, GIV, GV& GVI were 5/15 (33.3%), 8/15 (53.3%), 10/15 (66.7%) and 9/15 (60%) respectively. In addition, there were significantly better outcomes in serum biochemical indexes such as ALT, AST, gamma-GT, ALP, and hepatic SOD and MDA in the fresh and microencapsulated groups than in PZQ-treated group, without great differences between the microencapsulated and the fresh transplanted groups

  18. Chronic hepatosplenic schistosomiasis mansoni: magnetic resonance imaging and magnetic resonance angiography findings

    Energy Technology Data Exchange (ETDEWEB)

    Bezerra, A.S.; D' Ippolito, G.; Caldana, R.P.; Cecin, A.O.; Ahmed, M.; Szejnfeld, J. [Dept. of Diagnostic Imaging, Federal Univ. of Sao Paulo, Sao Paulo (Brazil)

    2007-02-15

    Purpose: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. Material and Methods: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. Results: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. Conclusion: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways.

  19. Schistosomal myeloradiculopathy due to Schistosoma mansoni: Report on 17 cases from an endemic area

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    Badr Hatem

    2011-01-01

    Full Text Available Background: After malaria, schistosomiasis is the second most prevalent tropical disease. The prevalence of oviposition in CNS of infected persons varies from 0.3 to 30%. The conus medullaris is a primary site of schistosomiasis, either granulomatous or acute necrotizing myelitis. Objective: To report the clinical, radiological, and laboratory results of spinal cord schistosomiasis (SCS and to design proper therapeutic regimens. Materials and Methods: Seventeen patients (13 males and four females with SCS were enrolled between 1994 and 2009 at Mansoura University Hospitals. Their median age at diagnosis was 19 years (13-30 years. Independent neurological, radiological, and laboratory assessments were performed for both groups, excluding pathological confirmation that was done earlier in eight patients (Group 1. In the group 2 (nine patients, indirect hemagglutination (IHA test for bilharziasis in blood and cerebrospinal fluid (CSF was performed. Higher positive titer in CSF than serum indicated SCS plus induction of antibilharzial and corticosteroid protocols for 12 months with a three-year follow-up. Results: Rate of neurological symptoms of granulomatous intramedullary cord lesion was assessed independently in 16 cases and acute paraparesis in one case. All patients in group 2 had positive IHA against Schistosoma mansoni with median CSF and serum ranges 1/640 and 1/320, respectively. Seven patients (41.18% had complete recovery, eight patients (47.06% showed partial recovery, and no response was reported in two patients (11.76% (P = 0.005. There was no recorded mortality in the current registry. Conclusions: Rapid diagnosis of SCS with early medical therapies for 12 months is a crucial tool to complete recovery.

  20. Differences in Brazilian strains of Schistosoma mansoni evaluated by means of morphometric analysis of cercariae of both sexes

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    José Roberto Machado-Silva

    2000-12-01

    Full Text Available Morphometrics of Brazilian strains (BH, SJ and CMO of Schistosoma mansoni cercariae were obtained with a computerized image analyzer (IMAGE PRO PLUS, MEDIA CYBERNETICS, considering the following characters: body area, tail, furcae, oral and ventral suckers and distance between them. For statistical analysis, the variance test (one-way Anova was applied and significant differences of p< 0.05 were considered. All morphometric values in the BH strain were significantly higher (p< 0.05 than in the others. Lower values were obtained in females of SJ strain for all characters, excepting the body area. Only this character showed to be significantly different in males and females of the three strains. Specimens of both sexes in the BH and SJ strains showed significant differences regarding all characters. It was observed that this morphometric analysis permits the characterization of strains and also the sex identification in S. mansoni cercariae. Due to its feasibility, this method can be applied as a tool in laboratories devoid of more complex equipment.

  1. Confirmed local endemicity and putative high transmission of Schistosoma mansoni in the Sesse Islands, Lake Victoria, Uganda

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    Kabatereine Narcis B

    2011-03-01

    Full Text Available Abstract The Sesse Islands, in the Ugandan portion of Lake Victoria, have long been considered a low transmission zone for intestinal schistosomiasis. Based on observations of high prevalence of Schistosoma mansoni infection in the northern-most islands of this archipelago, a follow-up survey was conducted to ascertain whether transmission was endemic to this island group, combining parasitological and malacological surveys. Prevalence of intestinal schistosomiasis was again observed to be high, as was intensity of infections which, combined with low reported incidence of treatment, suggests that chemotherapy-based control initiatives are not being maximally effective in this region as high levels of population movement between islands and districts are confounding. The local disease transmission was confirmed by the observations of high abundance of Biomphalaria, as well as field-caught snails shedding S. mansoni cercariae. DNA sequencing of 12 cercariae revealed common mitochondrial cox1 haplotypes, as well as, novel ones, consistent with the high genetic diversity of this parasite in Lake Victoria. Intestinal schistosomiasis is firmly endemic in parts of the Sesse Islands and more broadly, this island group provides an insight into the future challenges to be faced by the Ugandan National Control Programme in regularly reaching these rather remote, inaccessible and largely itinerant communities.

  2. SmShb, the SH2-Containing Adaptor Protein B of Schistosoma mansoni Regulates Venus Kinase Receptor Signaling Pathways

    Science.gov (United States)

    Morel, Marion; Vanderstraete, Mathieu; Cailliau, Katia; Hahnel, Steffen; Grevelding, Christoph G.; Dissous, Colette

    2016-01-01

    Venus kinase receptors (VKRs) are invertebrate receptor tyrosine kinases (RTKs) formed by an extracellular Venus Fly Trap (VFT) ligand binding domain associated via a transmembrane domain with an intracellular tyrosine kinase (TK) domain. Schistosoma mansoni VKRs, SmVKR1 and SmVKR2, are both implicated in reproductive activities of the parasite. In this work, we show that the SH2 domain-containing protein SmShb is a partner of the phosphorylated form of SmVKR1. Expression of these proteins in Xenopus oocytes allowed us to demonstrate that the SH2 domain of SmShb interacts with the phosphotyrosine residue (pY979) located in the juxtamembrane region of SmVKR1. This interaction leads to phosphorylation of SmShb on tyrosines and promotes SmVKR1 signaling towards the JNK pathway. SmShb transcripts are expressed in all parasite stages and they were found in ovary and testes of adult worms, suggesting a possible colocalization of SmShb and SmVKR1 proteins. Silencing of SmShb in adult S. mansoni resulted in an accumulation of mature sperm in testes, indicating a possible role of SmShb in gametogenesis. PMID:27636711

  3. SmShb, the SH2-Containing Adaptor Protein B of Schistosoma mansoni Regulates Venus Kinase Receptor Signaling Pathways.

    Science.gov (United States)

    Morel, Marion; Vanderstraete, Mathieu; Cailliau, Katia; Hahnel, Steffen; Grevelding, Christoph G; Dissous, Colette

    2016-01-01

    Venus kinase receptors (VKRs) are invertebrate receptor tyrosine kinases (RTKs) formed by an extracellular Venus Fly Trap (VFT) ligand binding domain associated via a transmembrane domain with an intracellular tyrosine kinase (TK) domain. Schistosoma mansoni VKRs, SmVKR1 and SmVKR2, are both implicated in reproductive activities of the parasite. In this work, we show that the SH2 domain-containing protein SmShb is a partner of the phosphorylated form of SmVKR1. Expression of these proteins in Xenopus oocytes allowed us to demonstrate that the SH2 domain of SmShb interacts with the phosphotyrosine residue (pY979) located in the juxtamembrane region of SmVKR1. This interaction leads to phosphorylation of SmShb on tyrosines and promotes SmVKR1 signaling towards the JNK pathway. SmShb transcripts are expressed in all parasite stages and they were found in ovary and testes of adult worms, suggesting a possible colocalization of SmShb and SmVKR1 proteins. Silencing of SmShb in adult S. mansoni resulted in an accumulation of mature sperm in testes, indicating a possible role of SmShb in gametogenesis.

  4. Immunological system and Schistosoma mansoni: co-evolutionary immunobiology. What is the eosinophil role in parasite-host relationship?

    Directory of Open Access Journals (Sweden)

    Henrique L Lenzi

    1997-12-01

    Full Text Available Schistosomes, ancestors and recent species, have pervaded many hosts and several phylogenetic levels of immunity, causing an evolutionary pressure to eosinophil lineage expression and response. Schistosoma mansoni adult worms have capitalized on the apparent adversity of living within the mesenteric veins, using the dispersion of eggs and antigens to other tissues besides intestines to set a systemic activation of several haematopoietic lineages, specially eosinophils and monocytes/macrophages. This activation occurs in bone marrow, spleen, liver, lymph nodes, omental and mesenteric milky spots (activation of the old or primordial and recent or new lymphomyeloid tissue, increasing and making easy the migration of eosinophils, monocytes and other cells to the intestinal periovular granulomas. The exudative perigranulomatous stage of the periovular reaction, which present hystolitic characteristics, is then exploited by the parasites, to release the eggs into the intestinal lumen. The authors hypothesize here that eosinophils, which have a long phylogenic story, could participate in the parasite - host co-evolution, specially with S. mansoni, operating together with monocytes/ macrophages, upon parasite transmission.

  5. High prevalence of Schistosoma mansoni in six health areas of - Kasansa health zone, Democratic Republic of the Congo: short report.

    Science.gov (United States)

    Linsuke, Sylvie; Nundu, Sabin; Mupoyi, Sylvain; Mukele, Rodin; Mukunda, Faustin; Kabongo, Madeleine Mbuyi; Inocêncio da Luz, Raquel; Van Geertruyden, Jean-Pierre; Van Sprundel, Marc; Boelaert, Marleen; Polman, Katja; Lutumba, Pascal

    2014-12-01

    School-aged children suffer the most from schistosomiasis infection in sub Saharan Africa due to poverty and limited sanitary conditions. Mapping of disease burden is recommended and there is a need of updating prevalence data which is as old as 20 years in the Democratic Republic of Congo. An epidemiological and parasitological study was carried out in 2011 in the health zone of Kasansa. Six health areas (HA) were included in the study. In each health area, one primary school was selected. School-aged children were screened for S. mansoni infection using parallel Kato-Katz and direct microscopy techniques. A total of 335 school-aged children were screened. The average prevalence was 82.7% and ranged between 59.5-94.9%. Four of the six HAs had a prevalence level over 91%. Of all infected children, about half 112 (43.2%) had light parasite density. These results demonstrate that Schistosoma mansoni infection is a bigger problem than anticipated and there is an urgent need to implement effective control measures. PMID:25521351

  6. High prevalence of Schistosoma mansoni in six health areas of - Kasansa health zone, Democratic Republic of the Congo: short report.

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    Sylvie Linsuke

    2014-12-01

    Full Text Available School-aged children suffer the most from schistosomiasis infection in sub Saharan Africa due to poverty and limited sanitary conditions. Mapping of disease burden is recommended and there is a need of updating prevalence data which is as old as 20 years in the Democratic Republic of Congo. An epidemiological and parasitological study was carried out in 2011 in the health zone of Kasansa. Six health areas (HA were included in the study. In each health area, one primary school was selected. School-aged children were screened for S. mansoni infection using parallel Kato-Katz and direct microscopy techniques. A total of 335 school-aged children were screened. The average prevalence was 82.7% and ranged between 59.5-94.9%. Four of the six HAs had a prevalence level over 91%. Of all infected children, about half 112 (43.2% had light parasite density. These results demonstrate that Schistosoma mansoni infection is a bigger problem than anticipated and there is an urgent need to implement effective control measures.

  7. Calomys callosus: an alternative model to study fibrosis in Schistosomiasis mansoni: the pathology of the acute phase

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    J. A. Lenzi

    1995-04-01

    Full Text Available Twenty Calomys callosus, Rengger, 1830 (Rodentia-Cricetidae were studied in the early stage of the acute schistosomal mansoni infection (42nd day. The same number of Swiss Webster mice were used as a comparative standard. Liver and intestinal sections, fixed in formalin-Millonig and embedded in paraffin, were stained with hematoxilin and eosin, PAS-Alcian Blue, pH = 1.0 and 2.5, Lennert's Giemsa, Picrosirius plus polarization microscopy, Periodic acid methanamine silver, Gomori's silver reticulin and resorcin-fuchsin. Immunohistological study (indirect immunofluorescence and peroxidase labeled extravidin-biotin methods was done with antibodies specific to pro-collagen III, fibronectin, elastin, condroitin-sulfate, tenascin, alpha smooth muscle actin, vimentin and desmin. The hepatic granulomas were small, reaching only 27 of the volume of the hepatic Swiss Webster granuloma. They were composed mainly by large immature macrophages, often filled by schistosomal pigment, characterizing an exsudative-macrophage granuloma type. The granulomas were situated in the parenchyma and in the portal space. They were often intravascular, poor of extracellular matrix components, except fibronectin and presented, sometimes alpha smooth muscle actin and vimentin positive cells. The C. callosus intestinal granulomas were similar to Swiss Webster, showing predominance of macrophages. Therefore, the C. callosus acquire very well the Schistosoma mansoni infection, without developing strong hepatic acute granulomatous reaction, suggesting lack of histopathological signs of hypersensitivity.

  8. The use of protein hydrolysate improves the protein intestinal absorption in undernourished mice infected with Schistosoma mansoni

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    Coutinho Eridan M.

    2002-01-01

    Full Text Available Patients residing in endemic areas for schistosomiasis in Brazil are usually undernourished and when they develop the hepatosplenic clinical form of the disease should usually receive hospital care, many of them being in need of nutritional rehabilitation before specific treatment can be undertaken. In the mouse model, investigations carried out in our laboratory detected a reduced aminoacid uptake in undernourished animals which is aggravated by a superimposed infection with Schistosoma mansoni. However, in well-nourished infected mice no dysfunction occurs. In this study, we tried to improve the absorptive intestinal performance of undernourished mice infected with S. mansoni by feeding them with hydrolysed casein instead of whole casein. The values obtained for the coefficient of protein intestinal absorption (cpia among well-nourished mice were above 90% (either hydrolysed or whole protein. In undernourished infected mice, however, the cpia improved significantly after feeding them with hydrolysed casein, animals reaching values close to those obtained in well-nourished infected mice.

  9. New approaches with different types of circulating cathodic antigen for the diagnosis of patients with low Schistosoma mansoni load.

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    Rafaella Grenfell

    Full Text Available BACKGROUND: Schistosomiasis mansoni is a debilitating and sometimes fatal disease. Accurate diagnosis plays a key role in patient management and infection control. However, currently available parasitological methods are laborious and lack sensitivity. The selection of target antigen candidates has turned out to be a promising tool for the development of more sensitive diagnostic methods. In our previous investigations, the use of crude antigens led to false-positive results. Recently, focus has been given to highly purified Schistosoma mansoni antigens, especially to circulating antigens. METHOD: Thus, our main goal was to test different types of circulating cathodic antigen glycoprotein (CCA, as "crude antigen," the protein chain of recombinant CCA and two individual peptides. These schistosome proteins/peptides were tested in a new diagnostic method employing immunomagnetic separation based on the improvement of antigen-antibody binding. PRINCIPAL FINDINGS: Use of recombinant CCA as a diagnostic antigen allowed us to develop a diagnostic assay with high sensitivity and specificity with no false-negative results. Interestingly, the "crude antigen" worked as a good marker for control of cure after praziquantel treatment. CONCLUSIONS/SIGNIFICANCE: Our new diagnostic method was superior to enzyme-linked immunosorbent assay in diagnosing low endemicity patients.

  10. An atlas for Schistosoma mansoni organs and life-cycle stages using cell type-specific markers and confocal microscopy.

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    James J Collins

    Full Text Available 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.

  11. Serological speciation of human schistosome infections by ELISA with a panel of three antigens

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    Turner, P; Lalloo, K; Bligh, J; Armstrong, M; Whitty, C J M; Doenhoff, M J; Chiodini, P L

    2004-01-01

    Aims: To find out whether serology can reliably speciate human schistosomiasis using a simple enzyme linked immunosorbent assay (ELISA) technique. Methods: Stored sera from 66 patients with microscopically confirmed schistosomiasis were subjected to ELISA using a panel of three antigens, namely: unfractionated Schistosoma mansoni soluble egg antigen (SEA); CEF6, a cationic fraction of SEA; and crude S margrebowiei egg antigen, prepared from an animal schistosome closely related to S haematobium. Results: The optical densities (ODs) obtained using CEF6 as antigen were significantly higher in sera from S mansoni infected patients than in sera from S haematobium infected patients (median OD, 0.810 v 0.595). Using S margrebowiei egg antigen, the optical densities were significantly higher in S haematobium sera than in S mansoni sera (median OD, 0.794 v 0.544). There was no significant difference in optical densities between S mansoni and S haematobium sera using SEA (median OD, 0.725 v 0.737). The ratio of ODs (CEF6 to S margrebowiei egg antigen) was calculated: a ratio of >1 indicated S mansoni infection (sensitivity, 88%) and a ratio of <1 indicated S haematobium infection (sensitivity, 84%). The odds ratio for S haematobium having an OD ratio of <1 was 36.8 (95% confidence interval, 7.0 to 194). Conclusions: The identity of the infecting species of schistosome can be determined using the panel of antigens described. SEA should be used to screen serum samples, and the CEF6 : S margrebowiei egg antigen ELISA optical density ratio can be used where serological speciation is required. PMID:15509682

  12. Long-term effect of mass chemotherapy, transmission and risk factors for Schistosoma mansoni infection in very low endemic communities of Venezuela.

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    Hofstede, Stefanie N; Tami, Adriana; van Liere, Genevieve A F S; Ballén, Diana; Incani, Renzo N

    2014-12-01

    The prevalence of Schistosoma mansoni infection in Venezuela has changed from high to low due mostly to successful control activities, including mass chemotherapy and molluscicide applications. This study examined the impact of mass chemotherapy on S. mansoni transmission and risk factors for infection 12 years after administration of praziquantel in Venezuela. Two relatively isolated rural communities were studied, one with snail control (Manuare) and the second without (Los Naranjos). A cross-sectional survey of randomly selected households included 226 (Manuare) and 192 (Los Naranjos) consenting participants. S. mansoni prevalence was determined using a combination of coprological (Kato-Katz) and serological (circumoval precipitin test, alkaline phosphatase immunoassay and Western blot) tests. Data on epidemiological and socioeconomic risk factors were obtained through individual structured interviews. Univariate analysis and multivariate logistic regression models identified independent risk factors for infection. Water sites were examined for the presence of Biomphalaria glabrata snails. Only one participant was positive by coprology. The overall prevalences according to the combined tests were 32.7% in Manuare and 26.6% in Los Naranjos. Lower prevalences (12.7% in Manuare and 13.2% in Los Naranjos) were found in children 25 years), contact with specific water sites, and being a farmer/non-specialised worker. Mass treatment with praziquantel applied once to endemic communities led to an important and long-lasting sustained reduction of S. mansoni infections independent of the application of snail control. A degree of low active transmission of S. mansoni persisted in the treated areas which was associated with similar factors in both communities. PMID:25128702

  13. Use of humanised rat basophilic leukaemia cell line RS-ATL8 for the assessment of allergenicity of Schistosoma mansoni proteins.

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    Daniel Wan

    2014-09-01

    Full Text Available Parasite-specific IgE is thought to correlate with protection against Schistosoma mansoni infection or re-infection. Only a few molecular targets of the IgE response in S. mansoni infection have been characterised. A better insight into the basic mechanisms of anti-parasite immunity could be gained from a genome-wide characterisation of such S. mansoni allergens. This would have repercussions on our understanding of allergy and the development of safe and efficacious vaccinations against helminthic parasites.A complete medium- to high-throughput amenable workflow, including important quality controls, is described, which enables the rapid translation of S. mansoni proteins using wheat germ lysate and subsequent assessment of potential allergenicity with a humanised Rat Basophilic Leukemia (RBL reporter cell line. Cell-free translation is completed within 90 minutes, generating sufficient amounts of parasitic protein for rapid screening of allergenicity without any need for purification. Antigenic integrity is demonstrated using Western Blotting. After overnight incubation with infected individuals' serum, the RS-ATL8 reporter cell line is challenged with the complete wheat germ translation mixture and Luciferase activity measured, reporting cellular activation by the suspected allergen. The suitability of this system for characterization of novel S. mansoni allergens is demonstrated using well characterised plant and parasitic allergens such as Par j 2, SmTAL-1 and the IgE binding factor IPSE/alpha-1, expressed in wheat germ lysates and/or E. coli. SmTAL-1, but not SmTAL2 (used as a negative control, was able to activate the basophil reporter cell line.This method offers an accessible way for assessment of potential allergenicity of anti-helminthic vaccine candidates and is suitable for medium- to high-throughput studies using infected individual sera. It is also suitable for the study of the basis of allergenicity of helminthic proteins.

  14. Nitric oxide monocyte production levels in patients with the hepatosplenic form of Scistosoma mansoni infection who underwent splenectomy, ligature of the left gastric vein and auto implantation of spleen tissue in the major omentum

    OpenAIRE

    Brandt Carlos Teixeira; Leite Carlos Roberto Carvalho; Manhaes-de-Castro Francisco Machado; Macedo Érika Michelle Correia de; Silva Rebecca Peixoto Paes; Castro Célia Maria Machado Barbosa de

    2006-01-01

    PURPOSE: To measure the levels of NO production by monocytes in patients with the hepatosplenic form of schistosomiasis mansoni who underwent splenectomy, ligature of the left gastric vein and auto implantation of spleen tissue in the major omentum. METHODS: Four groups of volunteers were enrolled in the investigation: G1 - 12 patients with S. mansoni infection in its hepatosplenic form without any kind of treatment (SMH); G2 - 13 SMH patients who underwent medical treatment and portal hypert...

  15. Formation and Controlled Drug Release Using a Three-Component Supramolecular Hydrogel for Anti-Schistosoma Japonicum Cercariae

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    Yibao Li

    2016-03-01

    Full Text Available A novel three-component supramolecular hydrogel based on riboflavin, melamine and amino acid derivatives were constructed for controlled release of pesticides, Niclosamide derivatives. The formation of hydrogel may be attributed to self-assemble via hydrogen bonding and π–π interaction, which have been researched via scanning electron microscopy (SEM and Fourier transform infrared (FT-IR spectra. The rheological experiments showed that the hydrogel materials and drug-loaded hydrogel all demonstrated good mechanical strength and high stability. Further experimental results indicated that the drug-loaded hydrogels show large drug loadings, long-term release time and relatively higher efficiency to anti-cercariae in the water environment.

  16. Hemostatic dysfunction is increased in patients with hepatosplenic schistosomiasis mansoni and advanced periportal fibrosis.

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    Luiz Arthur Calheiros Leite

    Full Text Available BACKGROUND: Schistosomiasis mansoni is an endemic parasitic disease and a public health problem in Northeast Brazil. In some patients, hepatic abnormalities lead to periportal fibrosis and result in the most severe clinical form, hepatosplenic schistosomiasis. This study aimed to evaluate whether abnormal blood coagulation and liver function tests in patients with hepatosplenic schistosomiasis (n = 55 correlate with the severity of their periportal fibrosis. METHODOLOGY/PRINCIPAL FINDINGS: Blood samples were used for liver function tests, hemogram and prothrombin time (International Normalized Ratio, INR. The blood coagulation factors (II, VII, VIII, IX and X, protein C and antithrombin IIa (ATIIa, plasminogen activator inhibitor 1 (PAI-1 and D-dimer were measured by photometry or enzyme linked immunosorbent assay. Hyperfibrinolysis was defined on the basis of PAI-1 levels and a D-dimer concentration greater than a standard cut-off of 483 ng/mL. Standard liver function tests were all abnormal in the patient group compared to healthy controls (n = 29, including raised serum transaminases (p<0.001 and lower levels of albumin (p = 0.0156. Platelet counts were 50% lower in patients, while for coagulation factors there was a 40% increase in the INR (p<0.001 and reduced levels of Factor VII and protein C in patients compared to the controls (both p<0.001. Additionally, patients with more advanced fibrosis (n = 38 had lower levels of protein C compared to those with only central fibrosis (p = 0.0124. The concentration of plasma PAI-1 in patients was one-third that of the control group (p<0.001, and D-dimer levels 2.2 times higher (p<0.001 with 13 of the 55 patients having levels above the cut-off. CONCLUSION/SIGNIFICANCE: This study confirms that hemostatic abnormalities are associated with reduced liver function and increased liver fibrosis. Of note was the finding that a quarter of patients with hepatosplenic schistosomiasis and

  17. Specific Schistosoma mansoni rat T cell clones. I. Generation and functional analysis in vitro and in vivo.

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    Pestel, J; Dissous, C; Dessaint, J P; Louis, J; Engers, H; Capron, A

    1985-06-01

    In an attempt to determine the role of schistosome-specific T cells in the immune mechanisms developed during schistosomiasis, Schistosoma mansoni-specific T cells and clones were generated in vitro and some of their functions analyzed in vitro and in vivo in the fischer rat model. The data presented here can be summarized as follows: a) Lymph node cells (LNC) from rats primed with the excretory/secretory antigens-incubation products (IPSm) of adult worms proliferate in vitro only in response to the homologous schistosome antigens and not to unrelated antigens (Ag) such as ovalbumin (OVA) or Dipetalonema viteae and Fasciola hepatica parasite extracts. b) After in vitro restimulation of the primed LNC population with IPSm in the presence of antigen-presenting cells (APC) and maintenance in IL 2-containing medium, the frequency of IPSm-specific T cells is increased and the T cells can be restimulated only in the presence of APC possessing the same major histocompatibility complex (MHC) antigens. c) Following appropriate limiting dilution assays (LDA) (1 cell/well), 10 IPSm-specific T cell clones were obtained, and two of four maintained in culture were tested for their helper activity because they expressed only the W3/13+ W3/25+ surface phenotypes. d) The two highly proliferating IPSm-specific T cell clones (G5 and E23) exhibit an IPSm-dependent helper activity, as shown by the increase in IgG production by IPSm-primed B cells. e) IPSm-T cell clone (G5) as well as IPSm-T cell lines when injected in S. mansoni-infested rats can exert an in vivo helper activity, which is characterized by an accelerated production of IgG antibodies specific for the previously identified 30 to 40 kilodaltons (kd) schistosomula surface antigens (Ag). As recent studies have demonstrated that rat monoclonal antibodies recognize some incubation products of adult S. mansoni as well as one of the 30 to 40 kd schistosomula surface antigens, and taking into account the fact that the T cell

  18. Molecular Characterization of the Schistosoma mansoni Zinc Finger Protein SmZF1 as a Transcription Factor

    Science.gov (United States)

    D'Astolfo, Diego S.; Cardoso, Fernanda C.; Rajão, Matheus A.; Mourão, Marina M.; Gava, Elisandra; Oliveira, Sérgio C.; Macedo, Andréa M.; Machado, Carlos R.; Pena, Sérgio D. J.; Kitten, Gregory T.; Franco, Glória R.

    2009-01-01

    Background During its development, the parasite Schistosoma mansoni is exposed to different environments and undergoes many morphological and physiological transformations as a result of profound changes in gene expression. Characterization of proteins involved in the regulation of these processes is of importance for the understanding of schistosome biology. Proteins containing zinc finger motifs usually participate in regulatory processes and are considered the major class of transcription factors in eukaryotes. It has already been shown, by EMSA (Eletrophoretic Mobility Shift Assay), that SmZF1, a S. mansoni zinc finger (ZF) protein, specifically binds both DNA and RNA oligonucleotides. This suggests that this protein might act as a transcription factor in the parasite. Methodology/Principal Findings In this study we extended the characterization of SmZF1 by determining its subcellular localization and by verifying its ability to regulate gene transcription. We performed immunohistochemistry assays using adult male and female worms, cercariae and schistosomula to analyze the distribution pattern of SmZF1 and verified that the protein is mainly detected in the cells nuclei of all tested life cycle stages except for adult female worms. Also, SmZF1 was heterologously expressed in mammalian COS-7 cells to produce the recombinant protein YFP-SmZF1, which was mainly detected in the nucleus of the cells by confocal microscopy and Western blot assays. To evaluate the ability of this protein to regulate gene transcription, cells expressing YFP-SmZF1 were tested in a luciferase reporter system. In this system, the luciferase gene is downstream of a minimal promoter, upstream of which a DNA region containing four copies of the SmZF1 putative best binding site (D1-3DNA) was inserted. SmZF1 increased the reporter gene transcription by two fold (p≤0.003) only when its specific binding site was present. Conclusion Taken together, these results strongly support the hypothesis

  19. Functional expression and characterization of Schistosoma mansoni cathepsin B and its trans-activation by an endogenous asparaginyl endopeptidase.

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    Sajid, Mohammed; McKerrow, James H; Hansell, Elizabeth; Mathieu, Mary A; Lucas, Kimberley D; Hsieh, Ivy; Greenbaum, Doron; Bogyo, Matthew; Salter, Jason P; Lim, Kee C; Franklin, Christopher; Kim, Jea-Hyoun; Caffrey, Conor R

    2003-09-01

    Peptidases are essential for the establishment and survival of the medically important parasite, Schistosoma mansoni. This helminth expresses a number of gut-associated peptidases that degrade host blood proteins, including hemoglobin, as a means of nutrition. Using irreversible affinity probes, we demonstrate that S. mansoni cathepsin B-like endopeptidase 1 (SmCB1) is the most abundant papain family cysteine peptidase in both the parasite gut and somatic extracts. SmCB1 zymogen (SmCB1pm) was functionally expressed in Pichia pastoris (4-11mgl(-1)). Monospecific and immunoselected antibodies raised against SmCB1pm localized the enzyme exclusively to the gut lumen and surrounding gastrodermis of adult worms. Recombinant SmCB1pm was unable to catalyze its activation, even at low pH. However, recombinant S. mansoni asparaginyl endopeptidase (SmAE), another gut-associated cysteine peptidase, processed and activated SmCB1pm in trans. Consistent with the known specificity of AEs, processing occurred on the carboxyl side of an asparagine residue, two residues upstream of the start of the mature SmCB1 sequence. The remaining pro-region dipeptide was removed by rat cathepsin C (dipeptidyl-peptidase I)-an action conceivably performed by an endogenous cathepsin C in vivo. The activated recombinant SmCB1 is biochemically identical to the native enzyme with respect to dipeptidyl substrate kinetics and pH profiles. Also, the serum proteins, hemoglobin, serum albumin, IgG, and alpha-2 macroglobulin were efficiently degraded. Further, a novel application of an assay to measure the peptidyl carboxypeptidase activity of SmCB1 and other cathepsins B was developed using the synthetic substrate benzoyl-glycinyl-histidinyl-leucine (Bz-Gly-His-Leu). This study characterizes the major digestive cysteine peptidase in schistosomes and defines novel trans-processing events required to activate the SmCB1 zymogen in vitro which may facilitate the digestive process in vivo.

  20. Schistosoma mansoni Egg, Adult Male and Female Comparative Gene Expression Analysis and Identification of Novel Genes by RNA-Seq

    Science.gov (United States)

    Anderson, Letícia; Amaral, Murilo S.; Beckedorff, Felipe; Silva, Lucas F.; Dazzani, Bianca; Oliveira, Katia C.; Almeida, Giulliana T.; Gomes, Monete R.; Pires, David S.; Setubal, João C.; DeMarco, Ricardo; Verjovski-Almeida, Sergio

    2015-01-01

    Background Schistosomiasis is one of the most prevalent parasitic diseases worldwide and is a public health problem. Schistosoma mansoni is the most widespread species responsible for schistosomiasis in the Americas, Middle East and Africa. Adult female worms (mated to males) release eggs in the hepatic portal vasculature and are the principal cause of morbidity. Comparative separate transcriptomes of female and male adult worms were previously assessed with using microarrays and Serial Analysis of Gene Expression (SAGE), thus limiting the possibility of finding novel genes. Moreover, the egg transcriptome was analyzed only once with limited bacterially cloned cDNA libraries. Methodology/Principal findings To compare the gene expression of S. mansoni eggs, females, and males, we performed RNA-Seq on these three parasite forms using 454/Roche technology and reconstructed the transcriptome using Trinity de novo assembly. The resulting contigs were mapped to the genome and were cross-referenced with predicted Smp genes and H3K4me3 ChIP-Seq public data. For the first time, we obtained separate, unbiased gene expression profiles for S. mansoni eggs and female and male adult worms, identifying enriched biological processes and specific enriched functions for each of the three parasite forms. Transcripts with no match to predicted genes were analyzed for their protein-coding potential and the presence of an encoded conserved protein domain. A set of 232 novel protein-coding genes with putative functions related to reproduction, metabolism, and cell biogenesis was detected, which contributes to the understanding of parasite biology. Conclusions/Significance Large-scale RNA-Seq analysis using de novo assembly associated with genome-wide information for histone marks in the vicinity of gene models constitutes a new approach to transcriptome analysis that has not yet been explored in schistosomes. Importantly, all data have been consolidated into a UCSC Genome Browser search

  1. Effect of skin colour and selected physical characteristics on Schistosoma mansoni dependent morbidity Efeito da cor da pele e certas características físicas na morbidade dependente de Schistosoma mansoni

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    C. B. Cançado

    1995-12-01

    Full Text Available The effect of the colour group on the morbidity due to Schistosoma mansoni was examined in two endemic areas situated in the State of Minas Gerais, Brazil. Of the 2773 eligible inhabitants, 1971 (71.1% participated in the study: 545 (27.6% were classified as white, 719 (36.5% as intermediate and 707 (35.9% as black. For each colour group, signs and symptoms of individuals who eliminated S.mansoni eggs (cases were compared to those who did not present eggs in the faeces (controls. The odds ratios were adjusted by age, gender, previous treatment for schistosomiasis, endemic area and quality of the household. There was no evidence of a modifier effect of colour on diarrhea, bloody faeces or abdominal pain. A modifier effect of colour on hepatomegaly was evident among those heaviest infected (> 400 epg: the adjusted odds ratios for palpable liver at the middle clavicular and the middle sternal lines were smaller among blacks (5.4 and 6.5, respectively and higher among whites (10.6 and 12.9 and intermediates (10.4 and 10.1, respectively. These results point out the existence of some degree of protection against hepatomegaly among blacks heaviest infected in the studied areas.O efeito da cor na morbidade associada ao Schistosoma mansoni foi estudado em duas áreas endêmicas situadas no Estado de Minas Gerais, Brasil. Dos 2773 habitantes elegíveis, 1971 (71,1% participaram do estudo: 545 (27,6% foram classificados como brancos, 719 (36,5% como intermediários e 707 (35,9% como negros. Os sinais e sintomas dos indivíduos que eliminavam ovos de S. mansoni nas fezes (casos foram comparados aos daqueles que não apresentavam ovos do parasita neste exame (controles. As razões de chance foram ajustadas por idade, gênero, tratamento anterior para a esquistossomose, área endêmica e qualidade do domicílio. Não houve evidência de um efeito modificador da cor para a ocorrência de diarréia, sangue nas fezes ou dor abdominal. Um efeito modificador da

  2. Prevalence of intestinal parasitic infections among children under five years of age with emphasis on Schistosoma mansoni in Wonji Shoa Sugar Estate, Ethiopia.

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    Yirgalem G/hiwot

    Full Text Available Intestinal parasite infections are major public health problems of children in developing countries causing undernutrition, anemia, intestinal obstruction and mental and physical growth retardation. This study was conducted to assess the prevalence of intestinal helminthic infections among children under five years of age with emphasis on Schistosoma mansoni in Wonji Shoa Sugar Estate, Ethiopia. A cross-sectional parasitological survey was conducted in under-five children living in Wonji Shoa Sugar Estate Ethiopia, April, 2013. Stool samples were collected and examined for intestinal parasites using single Kato-Katz and single Sodium acetate-acetic acid-formalin (SAF solution concentration methods. Out of 374 children examined using single Kato-Katz and single SAF-concentration methods, 24.3% were infected with at least one intestinal parasite species. About 10.4%, 8.8%, 4.6%, 2.9%, 1.6% and 0.8% of the children were infected with Hymenolepis nana, Schistosoma mansoni, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworm, respectively. Prevalence of double, triple and quadruple intestinal helminthic infection was 6.4%, 0.54% and 1.1%, respectively. A significant increase in prevalence of S. mansoni (8.3% versus 3.2% and T. trichiura (2.7% versus 0.5% infection was observed when determined via the single Kato-Katz method compared to the prevalence of the parasites determined via the single SAF-concentration method. On the other hand, the single SAF-concentration method (9.1% revealed a significantly higher prevalence of H. nana infection than the single Kato-Katz (1.6% does. In conclusion, intestinal helminths infections particularly S. mansoni and H. nana were prevalent in under-five children of Wonji Shoa Sugar Estate. Including praziquantel treatment in the deworming program as per the World Health Organization guidelines would be vital to reduce the burden of these diseases in areas where S. mansoni and H. nana

  3. Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818 em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae

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    Omar dos Santos Carvalho

    1976-10-01

    Full Text Available Junto ao Lago da Pampulha, Belo Horizonte, MG, foram capturados (julho/72-novembro/73 28 exemplares de Holochilus brasiliensis, dos quais 11 (39,3% eliminavam nas fezes ovos viáveis de S. mansoni. Miracídios da cepa mencionada ("H" infectaram Biomphalaria glabrata e as cercárias obtidas também infectaram camundongos albinos, recuperando-se, ao final do experimento, 35,3% de vermes adultos. Por outro lado, cercárias de cepa humana ("LE" de S. mansoni infectaram sete exemplares de H. brasiliensis, nascidos em laboratório, recuperando-se no fim de 60 dias, 30,5% de vermes adultos. Estudos anatomapatológicos de H. brasiliensis demonstraram infecção generalizada, encontrando-se granuloma no esôfago, estômago, intestino (delgado e grosso, fígado, baço, pâncreas e linfonodos abdominais. Espessamentos fibrosos da íntima da veia porta, granulomas em espaços porta e fibrose incipiente dos espaços porta e interlobular foram lesões decorrentes da presença de ovos de S. mansoni encontrados no fígado. Em ambiente semi-natural, foi possível fechar o ciclo do S. mansoni sem direta participação humana, utilizando-se B. glabrata experimentalmente infectadas com trematódeos da cepa "LE", H. brasiliensis nascidos em laboratório e B. glabrata nascida no ambiente semi-natural estabelecido. Verificou-se que ambas as cepas ("H" e "LE" comportaram-se de maneira análoga, não sendo verificadas, também, diferenças morfológicas entre os ovos e vermes adultos de ambas. As observações, realizadas no campo e no laboratório demonstraram que o Holochilus brasiliensis é bom hospedeiro de Schistosoma mansoni. Assim, em determinadas áreas e sob certas condições ecológicas, o cricetídeo em questão poderá, efetivamente, integrar-se ao ciclo do trematódeo na natureza, independente ou paralelamente à presença do homem. Assinala-se, finalmente, que o presente trabalho relata o segundo fechamento do ciclo biológico de S. mansoni em condi

  4. Prevalência da esquistossomose mansoni e de parasitoses intestinais em escolares da área rural do Município de Jaboticatubas, MG, 1992-1993

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    Geraldo Cunha Cury

    1994-12-01

    Full Text Available Estagiários do Internato Rural da Faculdade de Medicina da UFMG realizaram levantamento da prevalência da esquistossomose mansoni e de parasitoses intestinais em 20 escolas da área rural do município de Jaboticatubas, MG. Foi feita avaliação sumária das condições de habitação e saneamento, e os escolares foram submetidos a exame clínico e parasitológico de fezes. Observou-se que 15,43% dos escolares apresentaram ovos de S. mansoni nas fezes, o que representou a parasitose de maior prevalência. Foram encontrados 13,76% de exames com a presença de G. lamblia; 12,89% de S. stercoralis; 11,13% de A. lumbricoides; 9,96% de ancilostomideos; 9,57% de E. histolytica, tendo os outros parasitas apresentado prevalências inferiores às citadas. Todas as crianças que apresentaram ovos de parasitas nas fezes foram tratadas. Os resultados encontrados mostram que a esquistossomose mansoni é um grave problema de saúde pública e que medidas na área do saneamento básico se fazem necessárias para controle da endemia.Students from a Rural Boarding house of UFMG School of Medicine performed a survey of prevalence of schistosomiasis mansoni and other intestinal parasites in 20 rural schools in Jaboticatubas, MG. An evaluation of house and sanitation conditions was made and stool parasitological examinations were realised in all school children. It was noticed that 15.43% of the children presented S. mansoni's ova in stool - that was the most prevalent parasite. From the examinations we verify 13.76% positive cases for G. lamblia; 12.89% for S. stercoralis; 11.13% for A. lumbricoides; 9.96% for hookworms; 9.57% for E. histolytica. The other parasites appeared with lower prevalence. All the children that presented parasite's ova in stool received treatment. The result that was found shows that schistosomiasis mansoni is a very serious problem of public health and basic sanitation actions are necessary to the endemic control.

  5. Biomphalaria straminea no Peru e sua suscetibilidade a cepas brasileiras de Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    C.A. Cuba Cuba

    1977-12-01

    Full Text Available Em Maio de 1973, um dos autores (C.A.C. coletou na localidade de Imacita, Província de Bagua, Departamento de Amazonas, vários espécimes de Biomphalaria straminea (Dunker, 1848, uma espécie que, até então, não havia sido assinalada no Peru. Descendentes destes indivíduos foram submetidos a provas de suscetibilidade às cepas BH e SJ de Schistosoma mansoni que, em condições naturais, evoluem em B. glabrata de Belo Horizonte e B. tenagophila de São José dos Campos, respectivamente. Oitenta espécimens foram expostos à cepa BH dos quais em 13 ou 16,2% a infecção evoluiu caracteristicamente até a formação de esporocistos secundários sem haver, contudo, eliminação de cercárias, mesmo no indivíduo que apresentou uma sobrevivência de 88 dias após a exposição. Não se verificou cura espontânea neste lote. Entre as 40 B. straminea expostas à cepa SJ 9 ou 22,5% infectaram-se, sendo que apenas duas eliminaram poucas cercárias aos 57 e 77 dias após a exposição, por dois dias consecutivos, tendo uma morrido e uma se curado espontaneamente. A cura espontânea do parasitismo foi notado em mais dois indivíduos, nos quais a infecção foi observada através da concha. Cortes histológicos seriados de 9 caramujos, expostos individualmente a 50 miracídios da cepa BH e fixados entre 6 e 120 horas após a exposição, mostraram esporocistos em desenvolvimento e esporocistos invadidos por amebócitos, sem formação de granulomas por parte do hospedeiro, fato assinalado em caramujos suscetíveis. A população estudada comportou-se experimentalmente de modo semelhante a outras populações de B. straminea testadas em laboratório, isto é, com baixa suscetibilidade, embora tal comportamento não afaste a possibilidade dela vir a manter o ciclo do parasita em sua área de distribuição.In May 1973 one of the Authors (C.A.C. collected specimens of Biomphalaria straminea (Dunker 1848 at imacita, Bagua Province, Amazonas, Pem. This

  6. Hycanthone e oxamniquine no tratamento de crianças portadoras de S. mansoni

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    Maria Zelia Rouquayrol

    1976-04-01

    Full Text Available Os autores apresentam resultado de tratamento com Hycanthone e com Oxamniquine efetuado em grupos de 36 crianças de 6 - 15 anos de idade, portadoras de S. mansoni, mais um grupo Controle (não portadores, de igual número perfazendp o total de 108 crianças. Os grupos eram homogêneos quanto à idade, peso, altura, condições clínicas (forma intestinal moderada e fatores sócio-econômico-sanitários. Eram todos residentes no perímetro irrigado da Curú-Recuperação, Pentecoste-Ceará, e filhos de funcionários do DNOCS. Foi efetuado tratamento com Hycanthone (2,3 m/kg a 2,7 mg/kg mais placebo de Oxamniquine (Grupo A, com Oxamniquine (11,4 mg/kg a 20 mg/kg mais placebo de Hycanthone (Grupo B e placebo dos dois medicamentos para o grupo Controle (Grupo C. Foram realizados exames de sangue (hemograma, transaminases e fosfatases alcalinas, sumário de urina e coproscopias (Hoffman, Kato qualitativo e quantitativo. Após tratamento todos os casos ficaram sob observação durante 72 horas e mais seguimento clínico e laboratorial durante 4 meses. Efetuados teste de t e de chi-quadrado todos os resultados são apresentados em tabelas e assim sumariados: 1 Hycanthone mostrou eficácia completa apresentando 100% como índice de cura. 2 Oxamniquine apresentou índice de cura de 80%, sendo que os 7 pacientes não curados tiveram significativa redução do número de ovos viáveis; destes, após o 29 tratamento, persistiram apenas 3 eliminando ovos viáveis. 3 Efeitos colaterais do tratamento com Hycanthone foram os seguintes: dor local, febre, náuseas, vômitos, cefaléia, tontura e sonolência. 4 Oxamniquine quase não afetou as crianças do ponto de vista de efeitos colaterais demonstráveis, tendo apresentado alguns casos com febre moderada e transitória e um caso com queixa de náusea. 5 Testes de função hepática revelaram alterações leves com aumento de TGO tanto no Grupo Hycanthone como no Grupo Oxamniquine (sem diferença estat

  7. High serum laminin and type IV collagen levels in schistosomiasis mansoni Elevação dos níveis séricos de laminina e colágeno tipo IV na esquistossomose mansoni

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    Rozangela Maria de Almeida Fernandes Wyszomirska

    2005-12-01

    Full Text Available BACKGROUND: Fibrosis is the process of excessive deposition of collagen and other extra cellular matrix components and large amounts of these components have been shown in periovular schistosomal granulomas, especially in the liver. Laminin and type IV collagen have been investigated in various hepatic disorders but their accuracy in fibrosis detection and in the evaluation of its progression in schistosomiasis have not been fully explained. AIM: To measure the serum levels of two markers of fibrosis, laminin and type IV collagen in schistosomiasis. PATIENTS AND METHODS: Sixty-four patients with different clinical forms of schistosomiasis mansoni: intestinal (group I, hepatointestinal (group II, compensated (group III and decompensated hepatosplenic (group IV and 18 healthy volunteers were included. RESULTS: Serum type IV collagen and laminin levels were significantly increased in patients compared to controls. At about clinical forms, serum type IV collagen was increased in groups II and IV, compared to controls and was significantly higher in group IV than in group I. Serum laminin was significantly increased in groups II, III and IV and was significantly higher in group IV than in group II. Serum type IV collagen was closely correlated with serum laminin in groups II and IV. CONCLUSIONS: Connective tissue marker levels did not correlate with periportal thickness. In schistosomiasis mansoni there is an increase of type IV collagen and laminin levels at the initial stage of the disease, as well as in advanced forms. We also suggest that these markers may be a useful predictor of disease progression.RACIONAL: A fibrose hepática é caracterizada por um aumento progressivo na quantidade do tecido conjuntivo hepático, que é formado pelo aumento na deposição de componentes da matriz extracelular, tendo sido encontrada grande quantidade desses componentes no fígado de pacientes com esquistossomose mansoni. A laminina e o colágeno tipo IV t

  8. Production of interferon-γ by natural killer cells and aging in chronic human schistosomiasis

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    E. Speziali

    2004-01-01

    Full Text Available BACKGROUNG: Aging is associated with several alterations in the phenotype, repertoire and activation status of lymphocytes as well as in the cytokine profile produced by these cells. As a lifelong condition, chronic parasitic diseases such as human schistosomiasis overlaps with the aging process and no systematic study has yet addressed the changes in immune response during infection with Schistosoma mansoni in older individuals.

  9. Evaluation of lung recovery assay for schistosomula in mice immunized with X-irradiated cercariae of Schistosoma mansoni

    International Nuclear Information System (INIS)

    The lung recovery assay for schistosomula has recently been used as a rapid method for measuring the state of immunity of a challenged animal. Its merit rests on the fact that the peak day of schistosomular recovery in the lungs of both normal and immune hosts falls on the same day and the degree of immunity can be measured by the percent of schistosomular recovery on this particular day. An evaluation of this method for mice immunized with highly X-irradiated cercariae of Schistosoma mansoni was made. The results indicate that in the immunized mice the peak day for the schistosomular recovery was delayed and the number of schistosomula recovered on the peak day was decreased. (orig./AJ) 891 AJ/orig.- 892 HIS

  10. Liver cirrhosis and splenomegaly associated with Schistosoma mansoni in a Sudanese woman in Malaysia:A case report

    Institute of Scientific and Technical Information of China (English)

    Yamuna Rajoo; Romano Ngui; Rohela Mahmud; Ng Rong Xiang; Sharifah FS Omar; G Kumar; Yvonne AL Lim; Arine Fadzlun Ahmad; Amirah Amir; Zurainee Mohamed Nor

    2015-01-01

    We report a case of a patient with Schistosoma mansoni infection who presented with liver cirrhosis and splenomegaly. She was diagnosed by a serological test and Kato-Katz thick smear stool examination. The patient was a 52-year-old woman from Sudan who came to Malaysia for a week to visit her sons. The patient lives in the middle of Rabak region, Sudan, a highly endemic area for schistosomiasis where her daily routine includes rearing of cows and farming. The site of toilet and sources of drinking water are canals and wells; both infested with snails. Patient had a long history of exposure and coming into contact with water from these canals and wells.

  11. LmSmdB: an integrated database for metabolic and gene regulatory network in Leishmania major and Schistosoma mansoni.

    Science.gov (United States)

    Patel, Priyanka; Mandlik, Vineetha; Singh, Shailza

    2016-03-01

    A database that integrates all the information required for biological processing is essential to be stored in one platform. We have attempted to create one such integrated database that can be a one stop shop for the essential features required to fetch valuable result. LmSmdB (L. major and S. mansoni database) is an integrated database that accounts for the biological networks and regulatory pathways computationally determined by integrating the knowledge of the genome sequences of the mentioned organisms. It is the first database of its kind that has together with the network designing showed the simulation pattern of the product. This database intends to create a comprehensive canopy for the regulation of lipid metabolism reaction in the parasite by integrating the transcription factors, regulatory genes and the protein products controlled by the transcription factors and hence operating the metabolism at genetic level.

  12. Differential anti-glycan antibody responses in Schistosoma mansoni-infected children and adults studied by shotgun glycan microarray.

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    Angela van Diepen

    Full Text Available BACKGROUND: Schistosomiasis (bilharzia is a chronic and potentially deadly parasitic disease that affects millions of people in (subtropical areas. An important partial immunity to Schistosoma infections does develop in disease endemic areas, but this takes many years of exposure and maturation of the immune system. Therefore, children are far more susceptible to re-infection after treatment than older children and adults. This age-dependent immunity or susceptibility to re-infection has been shown to be associated with specific antibody and T cell responses. Many antibodies generated during Schistosoma infection are directed against the numerous glycans expressed by Schistosoma. The nature of glycan epitopes recognized by antibodies in natural schistosomiasis infection serum is largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: The binding of serum antibodies to glycans can be analyzed efficiently and quantitatively using glycan microarray approaches. Very small amounts of a large number of glycans are presented on a solid surface allowing binding properties of various glycan binding proteins to be tested. We have generated a so-called shotgun glycan microarray containing natural N-glycan and lipid-glycan fractions derived from 4 different life stages of S. mansoni and applied this array to the analysis of IgG and IgM antibodies in sera from children and adults living in an endemic area. This resulted in the identification of differential glycan recognition profiles characteristic for the two different age groups, possibly reflecting differences in age or differences in length of exposure or infection. CONCLUSIONS/SIGNIFICANCE: Using the shotgun glycan microarray approach to study antibody response profiles against schistosome-derived glycan elements, we have defined groups of infected individuals as well as glycan element clusters to which antibody responses are directed in S. mansoni infections. These findings are significant for further

  13. 5-lipoxygenase pathway is essential for the control of granuloma extension induced by Schistosoma mansoni eggs in lung.

    Science.gov (United States)

    Toffoli da Silva, Gabriel; Espíndola, Milena Sobral; Fontanari, Caroline; Rosada, Rogerio Silva; Faccioli, Lúcia Helena; Ramos, Simone Gusmão; Rodrigues, Vanderlei; Frantz, Fabiani Gai

    2016-08-01

    According to WHO, it is estimated that approximately 2 billion people are infected with intestinal helminths worldwide and the number of people who are cured of these diseases is relatively low, resulting in a large percentage of chronically infected individuals. Schistosomiasis is one of the most important parasitic diseases present in developing countries configuring it as a serious public health problem, directly related to poverty and social disadvantage. Once the parasite infection is established, Schistosoma mansoni eggs fall into the bloodstream and are trapped in the liver microcirculation where a strong granulomatous response and fibrosis formation occurs. In the experimental model, granulomas develop in the mouse lung after intravenous injection of purified eggs. Here we aim to understand how leukotrienes are involved in the granuloma formation. Leukotrienes are lipid mediators derived from arachidonic acid metabolites via 5-lipoxygenase (5LO) enzyme. They are potent proinflammatory agents and induce recruitment, cell activation, regulation of microbicidal activity of polymorphonuclear and mononuclear cells. In this study, 5LO deficient mice (5LO(-/-)) were inoculated with S. mansoni eggs for evaluation of immunopathological parameters involved in the induction of type 2 granulomas. We showed that in the absence of leukotrienes, the size of granulomas were decreased comparing to the wild type mice and the inflammatory compromised areas had a lower extension. In 5LO(-/-) mice granulomas presented extensive areas of fibrosis, detected by α-SMA expression along the lesions, indicating remodeling in attempt to reestablish the normal tissue. Also, comparing to WT mice we detected decrease of IL-4 and IL-13 and increase of TGF-β in the lung of 5LO(-/-), but these mice failed to produce protective IFN-γ and IL-12. These results evidenced 5-Lipoxygenase as an important pathway during lung injury due to Schistosoma-eggs injection. PMID:27262746

  14. Indirect effects of oral tolerance to ovalbumin interfere with the immune responses triggered by Schistosoma mansoni eggs

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    Carvalho C.R.

    2002-01-01

    Full Text Available The objective of the present study was to investigate whether the injection of a tolerated protein (indirect effects affects the formation of granulomas around Schistosoma mansoni eggs trapped in the lungs after intravenous (iv injection into normal (noninfected C57BL/6 mice (6 animals per group. To induce oral tolerance to chicken egg ovalbumin a 1/5 dilution of egg white in water was offered ad libitum in a drinking bottle for 3 days. Control mice received water. After 7 days, control and experimental animals were injected iv with 2,000 S. mansoni eggs through a tail vein. In some mice of both groups the iv injection of eggs was immediately followed by intraperitoneal (ip immunization with 10 µg of dinitrophenylated conjugates of ovalbumin (DNP-Ova emulsified in complete Freund's adjuvant (CFA or only CFA; 18 days later, mice were bled and killed by ether inhalation. The lungs were fixed in formalin and embedded in paraffin. Serial sections of 5 µm were stained with Giemsa, Gomori's silver reticulin and Sirius red (pH 10.2. Granuloma diameters were measured in histological sections previously stained with Gomori's reticulin. Anti-DNP and anti-soluble egg antigen (SEA antibodies were analyzed by ELISA. In mice orally tolerant to ovalbumin the concomitant ip injection of DNP-Ova resulted in significantly lower anti-SEA antibodies (ELISA*: 1395 ± 352 in non-tolerant and 462 ± 146 in tolerant mice and affected granuloma formation around eggs, significantly decreasing granuloma size (area: 22,260 ± 2478 to 12,993 ± 3242 µm². Active mechanisms triggered by injection of tolerated antigen (ovalbumin reduce granuloma formation.

  15. Assessment of Schistosoma mansoni induced intestinal inflammation by means of eosinophil cationic protein, eosinophil protein X and myeloperoxidase before and after treatment with praziquantel

    DEFF Research Database (Denmark)

    Reimert, Claus Michael; Tukahebwa, Edridah M.; Kabatereine, Narcis B.;

    2008-01-01

    Western Uganda where Schistosoma mansoni is endemic. Samples were collected before treatment and 5, 15, 20 and 52 weeks after treatment with praziquantel. Significantly increased levels of faecal ECP and EPX were found in S. mansoni infected individuals (n=155) compared to the levels found in stools from...... found between faecal egg counts and faecal concentrations of ECP and EPX. Treatment with praziquantel induced a significant decline in both ECP and EPX, but only a non-significant reduction in faecal MPO. Following reinfection and despite of very low infection intensities, the protein levels increased...... significantly reaching the pre-treatment level (ECP and EPX) or levels significantly higher than the pre-treatment levels (MPO). This response pattern may imply a rebound effect during reinfection following treatment and resolution of immune regulatory immunosuppressive mechanisms in function during the chronic...

  16. Morbidade da esquistossomose mansoni no Brasil. I - Estudo de 4.652 casos observados no Rio de Janeiro de 1960 a 1979 Morbidity of schistosomiasis mansoni in Brazil. I - Study of 4652 cases observed in Rio de Janeiro from 1960 to 1979

    Directory of Open Access Journals (Sweden)

    J. Rodrigues Coura

    1982-03-01

    Full Text Available No período de vinte anos (1960-1979, os autores observaram na Clínica de Doenças Infecciosas e Parasitárias da Faculdade de Medicina da Universidade Federal do Rio de Janeiro, sediada no Pavilhão Carlos Chagas do Hospital São Francisco de Assis, 4.652 casos de esquistossomose mansoni procedentes de 18 Estados do Brasil. Entre os casos observados 87,18% eram da forma hepatointestinal e 12,82% da forma hepatoesplênica entre os quais 30 tinham a forma pulmonar associada. Adicionalmente 30 casos da forma aguda ou toxémica foram estudados no mesmo Serviço, em famílias residentes no Rio de Janeiro. Além da observação clínica e do estudo epidemiológico incluindo o perfil migratório de cada caso e da casuística como um todo, foram realizados exames complementares como hemograma, mielograma, dosagem de transaminases, provas de função hepática, eletroforese de proteínas séricas, biópsia hepática, radiografias de tórax e de esôfago, esplenoportografia, eletrocardiograma e estudos hemodinâmicos do sistema porta, do coração e da artéria pulmonar em grupos de pacientes selecionados.A study of 4.652 schistosomiasis mansoni patients from 18 different States in Brazil, indicates a general picture of the morbidity of this disease in the country. Patients migrants (4.652 from different States were studied in the Department of Tropical Medicine of Federal University of Rio de Janeiro, between 1960 and 1979, with the following parameters: selected by a positive stool examination (sedimentation technique, clinical and epidemiological evaluation to determine the clinical form, migration pattern, age, sex and race. A routine chest X ray, E. C. G., haematologic and biochemistry tests, were performed. In a selected group of hepatosplenic cases a liver, biopsy, splenoportography and a portal hemodynamic study were done. Although some regional, familial, racial and/or individual differences in morbidity have been observed, the intensity of the

  17. Systematic Review and Meta-analysis of the Impact of Chemical-Based Mollusciciding for Control of Schistosoma mansoni and S. haematobium Transmission

    OpenAIRE

    King, Charles H.; Laura J Sutherland; Bertsch, David

    2015-01-01

    Background Programs for schistosomiasis control are advancing worldwide, with many benefits noted in terms of disease reduction. Yet risk of reinfection and recurrent disease remain, even in areas with high treatment coverage. In the search for means to better prevent new Schistosoma infections, attention has returned to an older strategy for transmission control, i.e., chemical mollusciciding, to suppress intermediate host snail species responsible for S. mansoni and S. haematobium transmiss...

  18. Systematic Review and Meta-analysis of the Impact of Chemical-Based Mollusciciding for Control of Schistosoma mansoni and S. haematobium Transmission.

    OpenAIRE

    King, Charles H.; Laura J Sutherland; David Bertsch

    2015-01-01

    Programs for schistosomiasis control are advancing worldwide, with many benefits noted in terms of disease reduction. Yet risk of reinfection and recurrent disease remain, even in areas with high treatment coverage. In the search for means to better prevent new Schistosoma infections, attention has returned to an older strategy for transmission control, i.e., chemical mollusciciding, to suppress intermediate host snail species responsible for S. mansoni and S. haematobium transmission. The ob...

  19. Fecal occult blood and fecal calprotectin as point-of-care markers of intestinal morbidity in Ugandan children with Schistosoma mansoni infection.

    OpenAIRE

    Amaya L Bustinduy; SOUSA-FIGUEIREDO, JOSÉ C.; Moses Adriko; Martha Betson; Alan Fenwick; Narcis Kabatereine; J Russell Stothard

    2013-01-01

    BACKGROUND: Calprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB) is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ). METHODS: 216 children (ages 3-9 years old) from Buliisa District in Lake Albert, Ug...

  20. Suscetibilidade aos agentes quimioterápicos de isolados de Schistosoma mansoni oriundos de pacientes tratados com oxamniquine e praziquantel e não curados

    Directory of Open Access Journals (Sweden)

    Neusa Araújo

    1996-10-01

    Full Text Available Foram estudados dez isolados de Schistosoma mansoni provenientes de pacientes residentes em Itaquara, Bahia, Brasil, tratados com oxamniquine eposteriormente com praziquantel, e ainda assim não curados. Caramujos (Biomphalaria glabrataj foram expostos a miracídios provenientes das fezes dos pacientes. Cercãrías eliminadas por estes caramujos e por moluscos coletados no peridomicílio dos pacientes foram utilizadas para infecção experimental de camundongos albinos. Os animais infectados foram tratados em dose única, via oral, com oxamniquine (25, 50 e 100 mg/kg ou praziquantel (100, 200 e 400mg/kg. Foram realizados estudos de análise e comparação de DNA de cercãrías de S. mansoni eliminadas pelos caramujos e de vermes adultos recolhidos de camundongos infectados experimentalmente com os isolados dos 10 pacientes e ainda de cercãrías de S. mansoni eliminadas por moluscos naturalmente infectados coletados em Itaquara. A cepa LE (mantida rotineiramente no laboratório foi usada como padrão de comparação da resposta aos agentes esquistossomicidas administrados. As respostas terapêuticas foram significativamente diferentes entre alguns dos isolados embora não fosse possível caracterizar nenhum como resistente. A análise dos perfis de amplificação de DNA nas cercãrías e nos vermes adultos dos isolados de S. mansoni demonstrou baixo grau de variabilidade indicando que estes são geneticamente próximos e revelando a ausência de rearranjos globais dentro dos genomas.

  1. Variations in helminth faecal egg counts in Kato-Katz thick smears and their implications in assessing infection status with Schistosoma mansoni.

    Science.gov (United States)

    Berhe, Nega; Medhin, Girmay; Erko, Birhanu; Smith, Tara; Gedamu, Selamawitt; Bereded, Dereje; Moore, Rashida; Habte, Endashaw; Redda, Abraham; Gebre-Michael, Teshome; Gundersen, Svein Gunnar

    2004-01-01

    Examination of stool specimens by Kato-Katz (K-K) thick smears is the standard method recommended by the WHO for field diagnosis of intestinal schistosomiasis. However, there is increasing concern that this technique has low diagnostic sensitivity. In 326 study subjects, we compared the diagnostic yield of examining one, three or five Kato-Katz thick smears prepared from one stool specimen using 41.7 mg templates. In a subset of 169 subjects who had no demonstrable Schistosoma mansoni eggs in their first three Kato-Katz thick smears, we assessed the comparative advantage of examining an additional three Kato-Katz thick smears from another stool specimen, taken four weeks later, to that of cumulative yield obtained by examining all five Kato-Katz thick smears derived from the first stool specimen. For all helminth infections, single Kato-Katz thick smear-based prevalence estimates were significantly lower than those obtained from triplet or quintet Kato-Katz thick smears. Prevalence of S. mansoni infection based on single, triplet and quintet Kato-Katz thick smears from one stool specimen were 31.3%, 45.7% and 52.1%, respectively. Prevalence estimate of S. mansoni based on quintet Kato-Katz thick smears from the first day stool specimens was not different from cumulative estimate obtained with two triplet Kato-Katz thick smears from two stool specimens, 52.1% and 52.8%, respectively. In conclusion, either examination of quintet Kato-Katz thick smears from one stool specimen using 41.7 mg template or initial triplet Kato-Katz thick smears from one stool specimen, and if these are negative, followed by examination of additional triplet Kato-Katz thick smears from subsequent day stool specimen can adequately assess individuals for infection status with S. mansoni. PMID:15533288

  2. Bases génétiques du polymorphisme de compatibilité dans l'interaction Schistosoma mansoni / Biomphalaria glabrata

    OpenAIRE

    Roger, Emmanuel

    2008-01-01

    The co-evolutionary dynamics that exist in certain invertebrate host / parasite interactions sometimes lead to a compatibility polymorphism, of which the molecular bases are unknown. To identify key molecules involved in this phenomenon in the Schistosoma mansoni / Biomphalaria glabrata model, we developed a comparative proteomics approach for the larval stages that interact with the invertebrate host. The qualitative and quantitative comparison of the proteomes of compatible and incompatible...

  3. Sustaining control of schistosomiasis mansoni in moderate endemicity areas in western Côte d’Ivoire: a SCORE study protocol

    OpenAIRE

    Rufin K Assaré; Knopp, Stefanie; N'Guessan, Nicaise A.; Yapi, Ahoua; Yves-Nathan T. Tian-Bi; Patrick K. Yao; Coulibaly, Jean T.; Ouattara, Mamadou; Meïté, Aboulaye; FENWICK, ALAN; N'Goran, Eliézer K.; Utzinger, Jürg

    2014-01-01

    Background Schistosomiasis is a parasitic disease that occurs in the tropics and subtropics. The mainstay of control is preventive chemotherapy with praziquantel. In Africa, an estimated 230 million people require preventive chemotherapy. In western Côte d’Ivoire, infections with Schistosoma mansoni are widespread. To provide an evidence-base for programme decisions about preventive chemotherapy to sustain control of schistosomiasis, a 5-year multi-country study with different treatment arms ...

  4. Identification of schistosoma mansoni antigens recognised by spleen cells of C57B1/6 mice immunized with ultraviolet-irradiated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Osman, A.; El Ridi, R. (Cairo Univ. (Egypt)); Guirguis, N. (VACSERA, El Agouza Cairo (Egypt). Biomedical Research Dept.); Dean, D.A. (U.S. Naval Medical Research Unit No. 3, Cairo (Egypt))

    1994-11-01

    Spleen cells of C57B1/6 mice immunized twice with Schistosoma mansoni cercariae attenuated by ultraviolet irradiation proliferated and produced interleukin-(I1)-2 and/or I1-4 in response to both soluble schistosomular and adult worm antigens of 72-68, 60-62, 50, 45, 29.5 and 28 kDa. All of these bands, except the 45 kDa, were also recognized by serum antibodies in Western blotting. (author).

  5. Comparing diagnostic accuracy of Kato-Katz, Koga agar plate, ether-concentration, and FLOTAC for Schistosoma mansoni and soil-transmitted helminths.

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    Dominik Glinz

    Full Text Available BACKGROUND: Infections with schistosomes and soil-transmitted helminths exert a considerable yet underappreciated economic and public health burden on afflicted populations. Accurate diagnosis is crucial for patient management, drug efficacy evaluations, and monitoring of large-scale community-based control programs. METHODS/PRINCIPAL FINDINGS: The diagnostic accuracy of four copromicroscopic techniques (i.e., Kato-Katz, Koga agar plate, ether-concentration, and FLOTAC for the detection of Schistosoma mansoni and soil-transmitted helminth eggs was compared using stool samples from 112 school children in Côte d'Ivoire. Combined results of all four methods served as a diagnostic 'gold' standard and revealed prevalences of S. mansoni, hookworm, Trichuris trichiura, Strongyloides stercoralis and Ascaris lumbricoides of 83.0%, 55.4%, 40.2%, 33.9% and 28.6%, respectively. A single FLOTAC from stool samples preserved in sodium acetate-acetic acid-formalin for 30 or 83 days showed a higher sensitivity for S. mansoni diagnosis (91.4% than the ether-concentration method on stool samples preserved for 40 days (85.0% or triplicate Kato-Katz using fresh stool samples (77.4%. Moreover, a single FLOTAC detected hookworm, A. lumbricoides and T. trichiura infections with a higher sensitivity than any of the other methods used, but resulted in lower egg counts. The Koga agar plate method was the most accurate diagnostic assay for S. stercoralis. CONCLUSION/SIGNIFICANCE: We have shown that the FLOTAC method holds promise for the diagnosis of S. mansoni. Moreover, our study confirms that FLOTAC is a sensitive technique for detection of common soil-transmitted helminths. For the diagnosis of S. stercoralis, the Koga agar plate method remains the method of choice.

  6. 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.

  7. Hycanthone e oxamniquine no tratamento de crianças portadoras de S. mansoni

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    Maria Zelia Rouquayrol

    1976-04-01

    Full Text Available Os autores apresentam resultado de tratamento com Hycanthone e com Oxamniquine efetuado em grupos de 36 crianças de 6 - 15 anos de idade, portadoras de S. mansoni, mais um grupo Controle (não portadores, de igual número perfazendp o total de 108 crianças. Os grupos eram homogêneos quanto à idade, peso, altura, condições clínicas (forma intestinal moderada e fatores sócio-econômico-sanitários. Eram todos residentes no perímetro irrigado da Curú-Recuperação, Pentecoste-Ceará, e filhos de funcionários do DNOCS. Foi efetuado tratamento com Hycanthone (2,3 m/kg a 2,7 mg/kg mais placebo de Oxamniquine (Grupo A, com Oxamniquine (11,4 mg/kg a 20 mg/kg mais placebo de Hycanthone (Grupo B e placebo dos dois medicamentos para o grupo Controle (Grupo C. Foram realizados exames de sangue (hemograma, transaminases e fosfatases alcalinas, sumário de urina e coproscopias (Hoffman, Kato qualitativo e quantitativo. Após tratamento todos os casos ficaram sob observação durante 72 horas e mais seguimento clínico e laboratorial durante 4 meses. Efetuados teste de t e de chi-quadrado todos os resultados são apresentados em tabelas e assim sumariados: 1 Hycanthone mostrou eficácia completa apresentando 100% como índice de cura. 2 Oxamniquine apresentou índice de cura de 80%, sendo que os 7 pacientes não curados tiveram significativa redução do número de ovos viáveis; destes, após o 29 tratamento, persistiram apenas 3 eliminando ovos viáveis. 3 Efeitos colaterais do tratamento com Hycanthone foram os seguintes: dor local, febre, náuseas, vômitos, cefaléia, tontura e sonolência. 4 Oxamniquine quase não afetou as crianças do ponto de vista de efeitos colaterais demonstráveis, tendo apresentado alguns casos com febre moderada e transitória e um caso com queixa de náusea. 5 Testes de função hepática revelaram alterações leves com aumento de TGO tanto no Grupo Hycanthone como no Grupo Oxamniquine (sem diferença estat

  8. In vitro effects of amodiaquine on paired Schistosoma mansoni adult worms at concentrations of less than 5 µg/mL

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    Kentaro Kato

    2013-04-01

    Full Text Available In this study, the in vitro effects of amodiaquine (AQ monotherapy on the egg output of paired adult Schistosoma mansoni worms and their survival during in vitro culture were assessed. In addition, the gross morphological alterations of male and female worms caused by AQ were visually observed under a dissecting microscope. AQ significantly reduced the daily egg output of paired adult S. mansoni worms following incubation for 14 days at 1-5 µg/mL, but not at 0.5 µg/mL, compared with the control group. AQ also reduced the survival of male and female worms at concentrations of 2 and 5 µg/mL, respectively. Moreover, exposure to 5 µg/mL AQ caused severe swelling and/or localisation of black content in the body of all male and female worms within one or two days of incubation; subsequently, shrinkage in the male worms and elongation in the female worms were observed. The initial morphological alterations caused by AQ occurred along the intestinal tract of the male and female worms. To our knowledge, this is the first study to report not only the efficacy of AQ at concentrations lower than 5 µg/mL on paired adult S. mansoni worms, but also the effects of AQ on the intestinal tracts of worms in in vitro culture.

  9. Synthesis of a sugar-based thiosemicarbazone series and structure-activity relationship versus the parasite cysteine proteases rhodesain, cruzain, and Schistosoma mansoni cathepsin B1.

    Science.gov (United States)

    Fonseca, Nayara Cristina; da Cruz, Luana Faria; da Silva Villela, Filipe; do Nascimento Pereira, Glaécia Aparecida; de Siqueira-Neto, Jair Lage; Kellar, Danielle; Suzuki, Brian M; Ray, Debalina; de Souza, Thiago Belarmino; Alves, Ricardo José; Sales Júnior, Policarpo Ademar; Romanha, Alvaro José; Murta, Silvane Maria Fonseca; McKerrow, James H; Caffrey, Conor R; de Oliveira, Renata Barbosa; Ferreira, Rafaela Salgado

    2015-05-01

    The pressing need for better drugs against Chagas disease, African sleeping sickness, and schistosomiasis motivates the search for inhibitors of cruzain, rhodesain, and Schistosoma mansoni CB1 (SmCB1), the major cysteine proteases from Trypanosoma cruzi, Trypanosoma brucei, and S. mansoni, respectively. Thiosemicarbazones and heterocyclic analogues have been shown to be both antitrypanocidal and inhibitory against parasite cysteine proteases. A series of compounds was synthesized and evaluated against cruzain, rhodesain, and SmCB1 through biochemical assays to determine their potency and structure-activity relationships (SAR). This approach led to the discovery of 6 rhodesain, 4 cruzain, and 5 SmCB1 inhibitors with 50% inhibitory concentrations (IC50s) of ≤ 10 μM. Among the compounds tested, the thiosemicarbazone derivative of peracetylated galactoside (compound 4i) was discovered to be a potent rhodesain inhibitor (IC50 = 1.2 ± 1.0 μM). The impact of a range of modifications was determined; removal of thiosemicarbazone or its replacement by semicarbazone resulted in virtually inactive compounds, and modifications in the sugar also diminished potency. Compounds were also evaluated in vitro against the parasites T. cruzi, T. brucei, and S. mansoni, revealing active compounds among this series. PMID:25712353

  10. A Comparative Study of the Organic Acid Content of the Hemolymph of Schistosoma mansoni-Resistant and Susceptible Strains of Biomphalaria glabrata

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    José Clecildo Barreto Bezerra

    1997-05-01

    Full Text Available The freshwater snail Biomphalaria glabrata is an intermediate host of the trematode Schistosoma mansoni. However, some strains of B. glabrata are resistant to successful infection by S. mansoni larvae. The present work examines the profile of organic acids present in S. mansoni-resistant and -susceptible strains of B. glabrata, in order to determine whether the type of organic acid present is related to susceptibility. The organic acids were extracted from the hemolymph of two susceptible B. glabrata strains (PR, Puerto Rico and Ba, Jacobina-Bahia from Brazil, and from the resistant strains 13-16-R1 and 10R2, using solid phase extraction procedures followed by high performance liquid chromatography. The organic acids obtained were analyzed and identified by comparison with known standards. Pyruvate, lactate, succinate, malate, fumarate, acetate, propionate, ß-hydroxybutyrate and acetoacetate were detected in all hemolymph samples. Under standard conditions, the concentration of each of these substances varied among the strains tested and appeared to be specific for each strain. An interesting variation was the low concentration of pyruvate in the hemolymph of PR-snails. Only the concentration of fumarate was consistently different (p£ 0.05 between resistant and susceptible strains

  11. Immunological and parasitological parameters in Schistosoma mansoni-infected mice treated with crude extract from the leaves of Mentha x piperita L.

    Science.gov (United States)

    Dejani, Naiara N; Souza, Laís C; Oliveira, Sandra R P; Neris, Débora M; Rodolpho, Joice M A; Correia, Ricardo O; Rodrigues, Vanderlei; Sacramento, Luis V S; Faccioli, Lúcia H; Afonso, Ana; Anibal, Fernanda F

    2014-08-01

    Schistosomiasis is a chronic disease caused by an intravascular trematode of the genus Schistosoma. Praziquantel is the drug used for treatment of schistosomiasis; nevertheless failure of treatment has been reported. Consequently, the identification of new effective schistosomicidal compounds is essential to ensure the effective control of schistosomiasis in the future. In this work we investigated the immunomodulatory and antiparasitic effects of the crude leaves extract of Mentha x piperita L. (peppermint) on murine Schistosomiasis mansoni. Female Balb/c mice were infected each with 50 S. mansoni cercariae and divided into three experimental groups: (I) untreated; (II) treated daily with M. x piperita L. (100mg/kg) and III) treated on 1/42/43 days post-infection with Praziquantel (500mg/kg). Another group with uninfected and untreated mice was used as a control. Subsequently, seven weeks post-infection, S. mansoni eggs were counted in the feces, liver and intestine. Worms were recovered by perfusion of the hepatic portal system and counted. Sera levels of IL-10, IL-5, IL-13, IFN-γ, IgG1, IgE and IgG2a were assayed by ELISA. Animals treated with a daily dose of M. x piperita L. showed increased sera levels of IL-10, IFN-γ, IgG2a and IgE. Besides, M. x piperita L. treatment promoted reduction in parasite burden by 35.2% and significant decrease in egg counts in the feces and intestine.

  12. Synthesis of a Sugar-Based Thiosemicarbazone Series and Structure-Activity Relationship versus the Parasite Cysteine Proteases Rhodesain, Cruzain, and Schistosoma mansoni Cathepsin B1

    Science.gov (United States)

    Fonseca, Nayara Cristina; da Cruz, Luana Faria; da Silva Villela, Filipe; do Nascimento Pereira, Glaécia Aparecida; de Siqueira-Neto, Jair Lage; Kellar, Danielle; Suzuki, Brian M.; Ray, Debalina; de Souza, Thiago Belarmino; Alves, Ricardo José; Júnior, Policarpo Ademar Sales; Romanha, Alvaro José; Murta, Silvane Maria Fonseca; McKerrow, James H.; Caffrey, Conor R.; de Oliveira, Renata Barbosa

    2015-01-01

    The pressing need for better drugs against Chagas disease, African sleeping sickness, and schistosomiasis motivates the search for inhibitors of cruzain, rhodesain, and Schistosoma mansoni CB1 (SmCB1), the major cysteine proteases from Trypanosoma cruzi, Trypanosoma brucei, and S. mansoni, respectively. Thiosemicarbazones and heterocyclic analogues have been shown to be both antitrypanocidal and inhibitory against parasite cysteine proteases. A series of compounds was synthesized and evaluated against cruzain, rhodesain, and SmCB1 through biochemical assays to determine their potency and structure-activity relationships (SAR). This approach led to the discovery of 6 rhodesain, 4 cruzain, and 5 SmCB1 inhibitors with 50% inhibitory concentrations (IC50s) of ≤10 μM. Among the compounds tested, the thiosemicarbazone derivative of peracetylated galactoside (compound 4i) was discovered to be a potent rhodesain inhibitor (IC50 = 1.2 ± 1.0 μM). The impact of a range of modifications was determined; removal of thiosemicarbazone or its replacement by semicarbazone resulted in virtually inactive compounds, and modifications in the sugar also diminished potency. Compounds were also evaluated in vitro against the parasites T. cruzi, T. brucei, and S. mansoni, revealing active compounds among this series. PMID:25712353

  13. Predicting frequency distribution and influence of sociodemographic and behavioral risk factors of Schistosoma mansoni infection and analysis of co-infection with intestinal parasites

    Directory of Open Access Journals (Sweden)

    Carla V.V. Rollemberg

    2015-05-01

    Full Text Available Geospatial analysis was used to study the epidemiology of Schistosoma mansoni, intestinal parasites and co-infections in an area (Ilha das Flores in Sergipe, Brazil. We collected individually georeferenced sociodemographic, behavioral and parasitological data from 500 subjects, analyzed them by conventional statistics, and produced risk maps by Kernel estimation. The prevalence rates found were: S. mansoni (24.0%, Trichuris trichiura (54.8%, Ascaris lumbricoides (49.2%, Hookworm (17.6% and Entamoeba histolytica (7.0%. Only 59/500 (11.8% individuals did not present any of these infections, whereas 279/500 (55.8% were simultaneously infected by three or more parasites. We observed associations between S. mansoni infection and various variables such as male gender, being rice farmer or fisherman, low educational level, low income, water contact and drinking untreated water. The Kernel estimator indicated that high-risk areas coincide with the poorest regions of the villages as well as with the part of the villages without an adequate sewage system. We also noted associations between both A. lumbricoides and hookworm infections with low education and low income. A. lumbricoides infection and T. trichiura infection were both associated with drinking untreated water and residential open-air sewage. These findings call for an integrated approach to effectively control multiple parasitic infections.

  14. Immunization with PIII, a fraction of Schistosoma mansoni soluble adult worm antigenic preparation, affects nitric oxide production by murine spleen cells

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    Diana Magalhães de Oliveira

    1998-01-01

    Full Text Available Nitric oxide (NO is an important effector molecule involved in immune regulation and defense. NO produced by cytokine-activated macrophages was reported to be cytotoxic against the helminth Schistosoma mansoni. Identification and characterization of S. mansoni antigens that can provide protective immunity is crucial for understanding the complex immunoregulatory events that modulate the immune response in schistosomiasis. It is, then, essential to have available defined, purified parasite antigens. Previous work by our laboratory identified a fraction of S. mansoni soluble adult worm antigenic preparation (SWAP, named PIII, able to elicit significant in vitro cell proliferation and at the same time lower in vitro and in vivo granuloma formation when compared either to SEA (soluble egg antigen or to SWAP. In the present work we report the effect of different in vivo trials with mice on their spleen cells ability to produce NO. We demonstrate that PIII-immunization is able to significantly increase NO production by spleen cells after in vitro stimulation with LPS. These data suggest a possible role for NO on the protective immunity induced by PIII.

  15. The combination of three faecal parasitological methods to improve the diagnosis of schistosomiasis mansoni in a low endemic setting in the state of Ceará, Brazil

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    Marta Cristhiany Cunha Pinheiro

    2012-11-01

    Full Text Available Laboratory diagnosis of intestinal schistosomiasis mansoni can be accomplished through various methods of stool examination to detect parasites, ranging from the most classic tests (Kato-Katz to several methods that are still undergoing validation. This study was conducted to assess two new parasite identification methods for diagnosing schistosomiasis mansoni in residents of a low endemic area in the municipality of Maranguape, in the state of Ceará, Brazil using the Kato-Katz method as a reference and serology (enzyme-linked immunosorbent assay for the screening of patients. The Kato-Katz, the saline gradient method and the Helmintex® method parasite identification methods were employed only in subjects who exhibited positive serologic tests. The test results were then analysed and treatment of positive individuals was subsequently performed. After comparing the test results, we observed that the saline gradient method and the Helmintex® method were more effective in diagnosing schistosomiasis mansoni in the study area compared with the Kato-Katz method.

  16. Colonização de Pomacea haustrum (Reeve, 1856 em localidade com esquistossomose mansoni: Baldim, MG (Brasil. (Prosobranchia, Pilidae Colonization of Pomacea haustrum (Reeve, 1856 at localility with Schistosomiasis mansoni: Baldim, MG (Brazil

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    Roberto Milward-de-Andrade

    1979-06-01

    Full Text Available Na localidade de Baldim, MG, Brasil, foram introduzidos, em agosto de 1972, 5.421 exemplares de Pomacea haustrum (Prosobranchia, Pilidae em 5 córregos e 2 valas, nos quais predominavam Biomphalaria glabrata (Say, 1818 e, secundariamente, B. straminea (Dunker, 1848. Entre 1968 e 1971, os índices de infecção da espécie B. glabrata por Schistosoma mansoni oscilaram de 2,1% a 11,9%. Em nenhum momento foram capturados B. straminea liberando cercárias daquele trematódeo. Após a introdução do pilídeo, apenas uma única vez detectou-se 2 (0,8% B. glabrata positivas. Observou-se decréscimo populacional de planorbineos e aumento de densidade de pomácea até 20,0 e 121,6 exemplares/m² em córregos e valas, respectivamente. A estimativa da densidade de F. haustrum foi feita através do método dos "quadrats". Foram coletados, de junho de 1968 a julho de 1972, 65,2% (1.526 dos planorbíneos. Porém, após a introdução do predador-competidor, foram registrados os seguintes dados: 1976, 15% (352; em 1977, 16,1% (377 e, em 1978, apenas 3,7% (87 do total dos exemplares capturados. As pomáceas, transferidas do ambiente lenítico (Sete Lagoas, MG, adaptaram-se às coleções lóticas de Baldim e foram capazes de substituir as populações originais de B. glabrata em vários biótopos, ou tornaram-se, pelo menos, dominantes, sem danos visíveis para os novos ecossistemas. Acredita-se que em outras situações análogas, Pomacea haustrum (Reeve, 1956 - e, por extensão, P. lineata (Spix, 1827, P. canaliculata (Lamark, 1822 e outras do mesmo táxon - poderão ser utilizadas, com sucesso, no controle biológico dos hospedeiros intermediários de Schistosoma mansoni.In the region of Baldim, MG (Brazil - a well-known Schistosoma mansoni endemic area where transmission control had already been unsuccessfully attempted through molluscicide, sanitary education and clinical treatment - 5,421 specimens of Pomacea haustrum (Prosobranchia, Pilidae were

  17. Advancing a vaccine to prevent human schistosomiasis.

    Science.gov (United States)

    Merrifield, Maureen; Hotez, Peter J; Beaumier, Coreen M; Gillespie, Portia; Strych, Ulrich; Hayward, Tara; Bottazzi, Maria Elena

    2016-06-01

    Several candidate human schistosomiasis vaccines are in different stages of preclinical and clinical development. The major targets are Schistosoma haematobium (urogenitial schistosomiasis) and Schistosoma mansoni (intestinal schistosomiasis) that account for 99% of the world's 252 million cases, with 90% of these cases in Africa. Two recombinant S. mansoni vaccines - Sm-TSP-2 and Sm-14 are in Phase 1 trials, while Smp80 (calpain) is undergoing testing in non-human primates. Sh28GST, also known as Bilhvax is in advanced clinical development for S. haematobium infection. The possibility remains that some of these vaccines may cross-react to target both schistosome species. These vaccines were selected on the basis of their protective immunity in preclinical challenge models, through human immune-epidemiological studies or both. They are being advanced through a combination of academic research institutions, non-profit vaccine product development partnerships, biotechnology companies, and developing country vaccine manufacturers. In addition, new schistosome candidate vaccines are being identified through bioinformatics, OMICs approaches, and moderate throughput screening, although the full potential of reverse vaccinology for schistosomiasis has not yet been realized. The target product profiles of these vaccines vary but many focus on vaccinating children, in some cases following mass treatment with praziquantel, also known as vaccine-linked chemotherapy. Several regulatory pathways have been proposed, some of which rely on World Health Organization prequalification. PMID:27036511

  18. Fecal Occult Blood and Fecal Calprotectin as Point-of-Care Markers of Intestinal Morbidity in Ugandan Children with Schistosoma mansoni Infection

    Science.gov (United States)

    Bustinduy, Amaya L.; Sousa-Figueiredo, José C.; Adriko, Moses; Betson, Martha; Fenwick, Alan; Kabatereine, Narcis; Stothard, J. Russell

    2013-01-01

    Background Calprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB) is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ). Methods 216 children (ages 3–9 years old) from Buliisa District in Lake Albert, Uganda were examined and treated with PZQ at baseline in October 2012 with 211 of them re-examined 24 days later for S. mansoni and other soil transmitted helminths (STH). POC calprotectin and FOB assays were performed at both time points on a subset of children. Associations between the test results and infection were analysed by logistic regression. Results Fecal calprotectin concentrations of 150–300 µg/g were associated with S. mansoni egg patent infection both at baseline and follow up (OR: 12.5 P = 0.05; OR: 6.8 P = 0.02). FOB had a very strong association with baseline anemia (OR: 9.2 P = 0.03) and medium and high egg intensity schistosomiasis at follow up (OR: 6.6 P = 0.03; OR: 51.3 P = 0.003). Both tests were strongly associated with heavy intensity S. mansoni infections. There was a significant decrease in FOB and calprotectin test positivity after PZQ treatment in those children who had egg patent schistosomiasis at baseline. Conclusions Both FOB and calprotectin rapid assays were found to correlate positively and strongly with egg patent S. mansoni infection with a positive ameloriation response after PZQ treatment indicative of short term reversion of morbidity. Both tests were appropriate for use in the field with excellent operational performance and reliability. Due to its lower-cost which makes its scale-up of use affordable, FOB could be immediately adopted as a monitoring tool for PC campaigns for efficacy evaluation before and after

  19. Efficacy and safety of praziquantel in preschool-aged children in an area co-endemic for Schistosoma mansoni and S. haematobium.

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    Jean T Coulibaly

    Full Text Available BACKGROUND: In sub-Saharan Africa the recommended strategy to control schistosomiasis is preventive chemotherapy. Emphasis is placed on school-aged children, but in high endemicity areas, preschool-aged children are also at risk, and hence might need treatment with praziquantel. Since a pediatric formulation (e.g., syrup is not available outside of Egypt, crushed praziquantel tablets are used, but the efficacy and safety of this treatment regimen is insufficiently studied. METHODOLOGY: We assessed the efficacy and safety of crushed praziquantel tablets among preschool-aged children (<6 years in the Azaguié district, south Côte d'Ivoire, where Schistosoma mansoni and S. haematobium coexist. Using a cross-sectional design, children provided two stool and two urine samples before and 3 weeks after treatment. Crushed praziquantel tablets, mixed with water, were administered at a dose of 40 mg/kg. Adverse events were assessed and graded 4 and 24 hours posttreatment by interviewing mothers/guardians. PRINCIPAL FINDINGS: Overall, 160 preschool-aged children had at least one stool and one urine sample examined with duplicate Kato-Katz thick smears and a point-of-care circulating cathodic antigen (POC-CCA cassette for S. mansoni, and urine filtration for S. haematobium diagnosis before and 3 weeks after praziquantel administration. According to the Kato-Katz and urine filtration results, we found high efficacy against S. mansoni (cure rate (CR, 88.6%; egg reduction rate (ERR, 96.7% and S. haematobium (CR, 88.9%; ERR, 98.0%. POC-CCA revealed considerably lower efficacy against S. mansoni (CR, 53.8%. Treatment was generally well tolerated, but moderately severe adverse events (i.e., body and face inflammation, were observed in four Schistosoma egg-negative children. CONCLUSIONS/SIGNIFICANCE: Crushed praziquantel administered to preschool-aged children at a dose of 40 mg/kg is efficacious against S. mansoni and S. haematobium in a co-endemic setting of C

  20. Fecal occult blood and fecal calprotectin as point-of-care markers of intestinal morbidity in Ugandan children with Schistosoma mansoni infection.

    Directory of Open Access Journals (Sweden)

    Amaya L Bustinduy

    2013-11-01

    Full Text Available BACKGROUND: Calprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ. METHODS: 216 children (ages 3-9 years old from Buliisa District in Lake Albert, Uganda were examined and treated with PZQ at baseline in October 2012 with 211 of them re-examined 24 days later for S. mansoni and other soil transmitted helminths (STH. POC calprotectin and FOB assays were performed at both time points on a subset of children. Associations between the test results and infection were analysed by logistic regression. RESULTS: Fecal calprotectin concentrations of 150-300 µg/g were associated with S. mansoni egg patent infection both at baseline and follow up (OR: 12.5 P = 0.05; OR: 6.8 P = 0.02. FOB had a very strong association with baseline anemia (OR: 9.2 P = 0.03 and medium and high egg intensity schistosomiasis at follow up (OR: 6.6 P = 0.03; OR: 51.3 P = 0.003. Both tests were strongly associated with heavy intensity S. mansoni infections. There was a significant decrease in FOB and calprotectin test positivity after PZQ treatment in those children who had egg patent schistosomiasis at baseline. CONCLUSIONS: Both FOB and calprotectin rapid assays were found to correlate positively and strongly with egg patent S. mansoni infection with a positive ameloriation response after PZQ treatment indicative of short term reversion of morbidity. Both tests were appropriate for use in the field with excellent operational performance and reliability. Due to its lower-cost which makes its scale-up of use affordable, FOB could be immediately adopted as a monitoring tool for PC campaigns for efficacy evaluation before and after treatment.

  1. Sensitivity and specificity of multiple Kato-Katz thick smears and a circulating cathodic antigen test for Schistosoma mansoni diagnosis pre- and post-repeated-praziquantel treatment.

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    Poppy H L Lamberton

    2014-09-01

    Full Text Available Two Kato-Katz thick smears (Kato-Katzs from a single stool are currently recommended for diagnosing Schistosoma mansoni infections to map areas for intervention. This 'gold standard' has low sensitivity at low infection intensities. The urine point-of-care circulating cathodic antigen test (POC-CCA is potentially more sensitive but how accurately they detect S. mansoni after repeated praziquantel treatments, their suitability for measuring drug efficacy and their correlation with egg counts remain to be fully understood. We compared the accuracies of one to six Kato-Katzs and one POC-CCA for the diagnosis of S. mansoni in primary-school children who have received zero to ten praziquantel treatments. We determined the impact each diagnostic approach may have on monitoring and evaluation (M&E and drug-efficacy findings.In a high S. mansoni endemic area of Uganda, three days of consecutive stool samples were collected from primary school-aged children (six - 12 years at five time-points in year one: baseline, one-week-post-, four-weeks-post-, six-months-post-, and six-months-one-week-post-praziquantel and three time-points in years two and three: pre-, one-week-post- and four-weeks-post-praziquantel-treatment/retreatment (n = 1065. Two Kato-Katzs were performed on each stool. In parallel, one urine sample was collected and a single POC-CCA evaluated per child at each time-point in year one (n = 367. At baseline, diagnosis by two Kato-Katzs (sensitivity = 98.6% or one POC-CCA (sensitivity = 91.7%, specificity = 75.0% accurately predicted S. mansoni infections. However, one year later, a minimum of three Kato-Katzs, and two years later, five Kato-Katzs were required for accurate diagnosis (sensitivity >90% and drug-efficacy evaluation. The POC-CCA was as sensitive as six Kato-Katzs four-weeks-post and six-months-post-treatment, if trace readings were classified as positive.Six Kato-Katzs (two/stool from three stools and/or one POC-CCA are required

  2. Efficacy and side effects of praziquantel in the treatment of Schistosomiasis mansoni in schoolchildren in Shesha Kekele Elementary School, Wondo Genet, Southern Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Berhanu Erko; Abraham Degarege; Konjit Tadesse; Asnake Mathiwos; Mengistu Legesse

    2012-01-01

    Objective: To evaluate the efficacy and side effects of praziquantel (PZQ) in the treatment of schistosomiasis in Ethiopia. Methods: In a cross-sectional study, stool specimens were collected from randomly selected 299 school children in Shesha Kekele Elementary School, Wondo Genet, Southern Ethiopia, in April 2010. Stool specimens were examined using a single Kato-Katz thick smear for Schistosoma mansoni (S. mansoni) ova. Children who were found positive for S. mansoni were treated with a single oral dose of PZQ at 40 mg/kg bw and interviewed for treatment-related symptoms 24 hours after drug administration. Four weeks post-treatment, stool specimens were collected from the same children and examined following the same procedure as in the pre-treatment. Drug efficacy was determined based on cure and egg reduction rates. Results: Pre-treatment prevalence of S. mansoni infection was 74.9% with geometric mean egg count of 268. The evaluated generic PZQ produced an overall cure rate of 73.6% (P<0.000 1, OR: 8.33, CI: 5.3-13.1) and egg reduction rate of 68.2% (P=0.03, F=0.64). The cure rate showed significant association with age (χ²=11, P=0.004), the highest rate being observed in the 15-22 age group. 83% of S. mansoni infected children showed various treatment-related symptoms, the most frequent being headache, nausea, and abdominal pain. These symptoms were associated with age (P<0.001) and pre-treatment intensity of infection (P<0.05). Conclusions: The present observations revealed relatively lower cure and egg reduction rates of the PZQ evaluated as compared to previous reports for other PZQ brands in Ethiopia. Hence, in depth studies are recommended to clarify whether the present relatively lower cure rate is the actual cure rate of the praziquantel evaluated, treatment failure, or reduced susceptibility of the parasite. Treatment-related side effects observed were transient and tolerable.

  3. Atividade quimioprofilática na esquistossomose mansoni de sabonetes contendo óleo essencial de frutos de Pterodon pubescens Chemoprophylactic activity in schistosomiasis mansoni of soaps containing essential oil from the fruits of Pterodon pubescens

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    Naftale Katz

    1993-04-01

    Full Text Available Foi estudada a ação quimioprofilática na esquistossomose experimental do óleo essencial do fruto de Pterodon pubescens Benth (Leguminosae, incorporado a diferentes formulações de sabonete. As formulações foram usadas topicamente nas caudas de camundongos que, imediatamente, 24,72 ou 168 horas após, foram expostos a cercárias de Schistosoma mansoni, pelo método de imersão da cauda. A proteção foi avaliada 45 dias após a exposição, quando os camundongos foram sacrificados e os vermes recolhidos por perfusão. Os resultados mostraram níveis de proteção variando de 0,0 a 100% conforme a formulação usada. Foi também desenvolvida uma metodologia que possibilitou a avaliação do sabonete protetor quando camundongos foram expostos à infecção natural em córregos infestados com caramujos na periferia de Belo Horizonte, MG. Resultados promissores foram obtidos, uma vez que houve proteção de 57,5 e 31,1% quando os animais foram ensaboados 24 e 48 horas antes. Estudos preliminares de avaliação de irritação e toxicidade foram favoráveis e mostraram que esta nova arma profilática poderá auxiliar no controle da esquistossomose.The chemoprophylactic action of the essential oil of the fruit of Pterodon pubescens Benth (Leguminosae, incorpored in different soap formulations, was studied in experimental schistosomiasis. The formulations were used locally on the tails of mice which were exposed to Schistosoma mansoni cercariae immediately, 24, 72 or 168 hours later by the method of tail immersion. Protection was evaluated 45 days after exposure when the mice were sacrificed and the worms collected by perfusion. The results showed levels of protection varying from 0.0 to 100% depending on the formulation used. A methodology that allowed the evaluation of soap protection of mice exposed to natural infection in snail infested streams on the outskirts of Belo Horizonte, MG, was also developed. Promising results were obtained in that

  4. Effects of non-specific immunopotentiators in experimental Schistosoma mansoni infection: II. Corynebacterium parvum Efeitos de imunopotenciadores não específicos na infecção experimental pelo Schistosoma mansoni: II. Corynebacterium parvum

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    Kirte M Teixeira

    1996-10-01

    Full Text Available The effects of Corynebacterium parvum on host protection, tissue reaction and "in vivo" chemotaxis in Schistosoma mansoni infected mice were studied. The C. parvum was given intraperitoneally using a dose of 0.7 mg, twice a week (for 4 weeks, thirty days before (prophylactic treatment or after infection (curative treatment. The host protection was evaluated through the recovery of adult worms by liver perfusion and was lower in the prophylactic group as compared to the control group (p = 0.018, resulting in 44% protection. The "in vivo" leukocyte response in both prophylactic and curative groups was higher as compared to the infected/non treated group (p = 0.009 and p = 0.003, respectively. Tissue reactions were described in the experimental and control groups, but there were not remarkable differences among them. The possible biological implications and relevance of the findings for the defensive response of the host and control of schistosomiasis are discussed.Neste trabalho foram avaliados os efeitos do Corynebacterium parvum na proteção do hospedeiro, reação tecidual e quimiotaxia "in vivo" em camundongos infectados pelo S. mansoni. O C. parvum foi dado intraperitonealmente usando uma dose de 0,7 mg, duas vezes por semana (durante 04 semanas, 30 dias antes (tratamento profilático e 30 dias após a infecção (tratamento curativo. A proteção do hospedeiro foi avaliada através da contagem de vermes adultos obtidos através da perfusão hepática de camundongos infectados e esse número foi bem menor no grupo profilático comparado ao grupo controle (p = 0,018, obtendo-se 44% de proteção. A resposta quimiotática "in vivo", nos grupos curativo e profilático, foi maior do que no grupo infectado/não tratado (p = 0,009 e p = 0,003, respectivamente. As reações teciduais foram descritas em todos os grupos, embora não tenha ocorrido diferenças marcantes entre eles. As possíveis implicações biológicas e a relevância dos achados

  5. Eficiência do diagnóstico coproscópico de Schistosoma mansoni em fezes prensadas The efficiency of the examination of compressed fecal samples for Schistosoma mansoni eggs

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    Horacio Manuel Santana Teles

    2003-07-01

    Full Text Available A eficácia do controle da esquistossomose depende em grande parte da sensibilidade da coproscopia. Passamos a utilizar, além da técnica de Kato-Katz, a de prensagem de fezes entre lâmina e lamínula de polipropileno, segundo Ferreira. De 1.282 amostras fecais colhidas entre 1998 e 2000 no Bairro da Palha, Município de Bananal, São Paulo, Brasil, 105 (8,2% resultaram positivas. A primeira técnica revelou 90 (7% e a segunda, 88 (6,9% amostras positivas. Os resultados concordaram, segundo a estatística kappa. Valores baixos de percentagens de positivos e de opg (ovos por grama de fezes, em Bananal, demandaram aumento do volume de material a examinar. Além de permitir a observação da viabilidade dos ovos de Schistosoma mansoni, a segunda técnica dispensa o uso de glicerina, de placa medidora e de tamisação; esta última, responsável por ulterior perda de precisão nas determinações de opg.The control of schistosomiasis depends mostly upon the sensitivity of stool examinations. We used both the Kato-Katz technique and the compression of samples between the slide and a polypropylene cover glass, according to Ferreira. Out of 1,282 samples collected between 1998 and 2000 in the Palha District, Municipality of Bananal, São Paulo State, Brazil, 105 (8.2 % were positive. The first and second methods revealed 90 (7% and 88 (6.9 % positive cases, respectively. According to the kappa statistic, both methods were in agreement. In Bananal, the proportion of positive cases and egg per gram (epg values are low, which calls for the examination of larger than usual volumes of feces. The viability of Schistosoma mansoni eggs can also be checked when using the second method, which dispenses with glycerin solution, measuring plates and sieves. The latter cause a further loss of precision in epg determinations.

  6. Esquistossomose na área hiperendêmica de Taquarendi: I Infecção pelo Schistosoma mansoni e formas graves Schistosomiasis in hyperendemic area of Taquarendi: I- Schistosoma mansoni infection and severe clinical forms

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    José Carlos Bina

    2003-04-01

    Full Text Available A localidade de Taquarendi (Bahia está situada em zona de caatinga, porém com pequena faixa de terra irrigada, onde se encontram caramujos Biomphalaria glabrata. Dos 1.532 habitantes, 1.105 (72,1% submeteram-se ao exame clínico e, destes, 1.058 (95,7% fizeram exame parasitológico de fezes. A prevalência da esquistossomose foi de 73,1%, sendo que 16,2% destes eliminavam mais de 1.000 ovos por grama de fezes. O exame clínico mostrou que o lobo esquerdo do f��gado estava aumentado e/ou endurecido em 54% dos pacientes e o baço foi palpado em 21,8%. Foram classificados como hepatosplênicas 9,8% dos examinados e como portadores da forma hepatintestinal avançada 3,7%. Houve relação direta entre estas formas clínicas da doença e a intensidade da carga parasitária acima de 1.000 ovos de S. mansoni por grama de fezes.The study was carried out in Taquarendi (Bahia, a caatinga zone with a small irrigated strip of land, where Biomphalaria glabrata snails are found. From the 1,532 inhabitants, 1,105 (72.1% were submitted to clinical examination and 1058 out of them (95.7% made stool examinations. Prevalence of schistosomiasis was 73.1% and 16.2% of these patients eliminated more than 1,000 eggs per gram of stool. By clinical examination, the size and the consistency of the left liver lobe were increased in 54% of the individuals and the spleen was palpable in 21.8%. The diagnosis of hepatosplenomegaly and of the advanced hepatointestinal clinical form was made, respectively, in 9.8% and 3.7%. A direct relationship between such clinical forms of the disease and the worm load over 1.000 S. mansoni eggs/g of fezes was found.

  7. Seleção genética de Biomphalaria glabrata e Biomphalaria tenagophila visando a alteração da suscetibilidade e resistência ao Schistosoma mansoni Genetic selection of Biomphalaria glabrata and Biomphalaria tenagophila seeking the alteration of the susceptibility and resistance to the Schistosoma mansoni

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    Nádia Regina Borim Zuim

    2005-10-01

    Full Text Available Gerações de Biomphalaria glabrata e Biomphalaria tenagophila selecionadas geneticamente para resistência e suscetibilidade ao Schistosoma mansoni das linhagens BH e SJ foram utilizadas no estudo da adaptação do trematódeo ao hospedeiro intermediário. As gerações dos planorbídeos foram obtidas por autofecundação dos moluscos que se apresentaram suscetíveis ou resistentes após a exposição aos miracídios de Schistosoma mansoni. Para Biomphalaria glabrata foram obtidas as gerações: Parental, F1S (Suscetível, F1R (Resistente, F2S e F2R. Para a Biomphalaria tenagophila foram estudadas as gerações: Parental, F1S, F1R e F50S. A comparação das taxas de infecção apresentadas pelas diferentes gerações mostrou que, em ambas as espécies, o aumento da suscetibilidade foi mais facilmente obtido do que o aumento da resistência. A dificuldade em aumentar a resistência do molusco ao S. mansoni tem fortes implicações epidemiológicas.Generations of Biomphalaria glabrata and Biomphalaria tenagophila selected genetically for resistance and susceptibility to Schistosoma mansoni of strains BH and SJ were used in a study of the trematode adaptation to the intermediate host. Descendants of the planorbids were obtained by self-fertilization of the mollusks that became susceptible or resistant after exposure to the miracidia of Schistosoma mansoni. For Biomphalaria glabrata they were obtained from the following generations: Parental, F1S (Susceptible, F1R (Resistant, F2S and F2R. For Biomphalaria tenagophila the studied generations were: Parental, F1S, F1R and F50S. The comparison of the infection rates presented by the different generations showed that the increase in susceptibility was more easily obtained in both species. The difficulty in increasing the resistance of the mollusks to Schistosoma mansoni has important epidemiologic implications.

  8. Anthelmintic activity in vitro and in vivo of Baccharis trimera (Less) DC against immature and adult worms of Schistosoma mansoni.

    Science.gov (United States)

    de Oliveira, Rosimeire Nunes; Rehder, Vera Lúcia Garcia; Oliveira, Adriana Silva Santos; Jeraldo, Veronica de Lourdes Sierpe; Linhares, Arício Xavier; Allegretti, Silmara Marques

    2014-04-01

    Although its efficiency against all Schistosoma species, praziquantel (PZQ) shows low efficacy against schistosomula and juvenile stages. The potential for development of resistance to PZQ has justified the search for new alternative chemotherapies. In this scenario, studies to new formulations, more comprehensive and without adverse effects, are being conducted. One viable and promising treatment is the study of medicinal plants as a new approach to the experimental treatment for Schistosomiasis. Amongst all the variety of the medicinal species studied, we can highlight Baccharis trimera (Less) DC, known as "Carqueja-amarga". This paper not only describes the effect of crude dichloromethane extract (DE) and aqueous fraction (AF) obtained from B. trimera, in vitro but also is the first one that investigates the in vivo efficacy of B. trimera against schistosomula, juvenile and adult worms of Schistosoma mansoni BH strain. In the experiment, mice were treated with DE, AF and PZQ (40 and 200mg/kg) over the period of larval development (3 and 30 post-infection; pi), and adult worms (60days post-infection; pi). The in vitro results show that the DE and AF effects are dose-dependents, being the 130μg/mL the most effective one in a shorter period of incubation. The exposure of the in vitro samples over adult parasites were able to inhibit 100% of the oviposition in females. Likewise caused the mortality of the parasites with morphological alterations on the tegument, on the suckers, oral and acetabulum, in both males and females after 6-72h of exposure. Additionally, the in vivo treatments against juvenile and adult infection were more effective compared to the control group untreated. Administrations of AF and DE in day 30pi (juvenile worms) show female worm total burden reductions of 75% and 68% respectively. At the same period of infection reductions of respectively 98% and 97% egg/g in the faeces were seen. In relation to the different egg developmental stages

  9. Avaliação terapêutica do oltipraz na infecção humana pelo S. mansoni

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    Silvino Alves de Carvalho

    1986-08-01

    Full Text Available Foram tratados com oltipraz, dose oral única de 30 mg/kg de peso, 72 indivíduos com esquistossomose mansoni, matriculados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As idades dos pacientes variaram de 7 a 58 anos, sendo que 8 (11,1% eram menores de 15 anos. Os principais efeitos colaterais consistiram em tonturas 22,2%, sonolência 22,2%, náuseas 22,2%, cefaléia, 9,7%, astenia 9,7%, parestesia 8,3%, vômitos 8,3!%, cólicas 7,0?/o, diarréia 4,2%, escotomas 2,8%, sialosquese 2,8%, nódulos dolorosos em extremidades 2,8% e outras manifestações clínicas em menor freqüência. A toxicidade do medicamento foi avaliada mediante a realização pré e pós-tratamento, de exames hematimétricos, de função renal (uréia e creatinina, hepática (enzimas de liberação hepato-canalicular e. bilirrubinas, cardíaca (ECG e neuropsiquiátrica (EEG. Não foram encontrados nos controles laboratoriais alterações relevantes ou que determinasse alguma repercussão clínica. O controle de cura verificou-se em 49 indivíduos, através de 8 coproscopias (no período de 6 meses subseqüente ao tratamento utilizando-se duas técnicas (Hoffman e Kato/Katz para cada amostra de fezes. Dos 29 individuos que tiveram as 8 coproscopias negativas, 20 realizaram biopsia retal, mostrando-se positiva em uma oportunidade, indicando 5% de "falsos negativos" com relação às coproscopias. O índice de cura para todas as faixas etárias foi de 59,2%. Os resultados obtidos demonstraram ser o oltipraz de relativa eficácia e determinante de efeitos tdxicos-colaterais sistêmicos no tratamento da esquistossomose mansoni.

  10. Factors associated with schistosomiasis mansoni in a population from the municipality of Jaboticatubas, State of Minas Gerais, Brazil

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    Cristiano Lara Massara

    2004-08-01

    Full Text Available Jaboticatubas is a municipality in the metropolitan region of Belo Horizonte which has been a target of a wide media release as "the capital of schistosomiasis" since the 1960's. In order to give support to a work based on an integrated control, we sought to identify the disease determinants at the site. A transversal study was carried out aimed at identifying prevalence rates of the disease and factors associated with the infection in the district of São José de Almeida, and two close localities, Cipó Velho and São José da Serra, all of them located in the municipality of Jaboticatubas. A parasitological survey was performed, applying the Kato-Katz method with two slides per sample in 1186 schoolchildren which represents 77% of all registered pupils in four public schools in 2001. Among these schoolchildren a number of 101 (8.6% prooved positive for Schistosoma mansoni eggs in their stool samples. A total of 64 families, whose schoolchildren had shown to be positive for schistosomiasis, also undertook examinations. As negative control, a random sample was collected from the 206 families, whose children had proven negative for schistosomiasis. The prevalence among 270 families (1304 people was 12%. To assess those who continued to have contact with possibly contaminated water, 1061 (81.4% people of the 270 families were interviewed. A multivariate analysis identified the following factors associated with the infection: time of residence in the area (short period, garbage disposal (use of deserted areas, gender (male, age (from 10 to 29 years, and water contact (daily and weekly. Further analysis of these factors revealed a close correlation between water contact and the disease, with a positive significant frequency concerning almost all those items. Depending on gender and age significant variations of water contact patterns associated with leisure and professional activities were found. A malacological survey on water collections in the

  11. Estudos sôbre a doença de Manson-Pirajá: (Esquistosomose pelo "Schistosoma Mansoni"

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    Octavio de Magalhães

    1947-03-01

    Full Text Available Os autores estudaram a doença produzida pelo «Schistosoma Mansoni» em Minas Gerais, Brasil. Fizeram um resumo histórico dos próprios trabalhos, iniciados no ano de 1933 em Belo Horizonte. Em 1937 um dos autores já havia mesmo, sentido a gravidade do problema sanitário, chamando a atenção para o Govêrno de Minas Gerais. Publicam os estudos que fizeram, inclu¬sive de lagos artificial da Pampulha, Belo Horizonte, e o parecer para ali combater a verminose. Dão os aspectos clínicos da doença, chamando a atenção para alguns dos mais importantes, clínicos e cirúrgicos da verminose. Referem às dificuldades do diagnostico, terapêutica e profilaxia, expondo a distribuição geográfica em Minas Gerais e publicando um mapa baseado nos estudos próprios e de outros colegas, feitos em 88 cidades mineiras. A média geral que os autores apuraram nas cidades infestadas foi de 13,70% para o trematódeo. Propõem, como já fizeram em 1941, a criação de um Serviço de combate à Esquistosomose no Brasil.(AUThe authours have studied the disease caused by the Schistosoma Mansoni in Minas Gerais, Brasil. They have made an historical summary of their own work, begun in 1933 in Belo Horizonte. In 1937 one of the authors, seeing the gravity of the sanitary problem, brought it to the notice of the government of Minas Gerais. They publish the studies they made, including that of the artificial lake of Pampulha, Belo Horizonte and their plan for fighting the verminosis. They give the clinical aspects of the disease, calling attention to the most important, clinical and surgical, of the verminosis. They refer to the difficulties of the diagnosis, therapeutics and prophylaxis, showing the geographical distribution in Minas Gerais and publish a map, based on their own studies and those of other colleagues, made in 88 cities of Minas Gerais. The average that the authors found in the infested cities, was 13.70 % for the trematodo. They suggest, as they had

  12. Evaluation and optimization of the Circulating Cathodic Antigen (POC-CCA) cassette test for detecting Schistosoma mansoni infection by using image analysis in school children in Mwanza Region, Tanzania

    DEFF Research Database (Denmark)

    Partal, Miriam Casacuberta; Kinunghi, Safari; Vennervald, Birgitte J;

    2016-01-01

    There is a need for diagnostic techniques which are sensitive, specific, rapid and easy to perform at the point-of-care. The aim of this study was to evaluate the diagnostic performance of the Circulating Cathodic Antigen (POC-CCA) assay for Schistosoma mansoni in four schools along the coast...... from a urine collected in the morning and a urine taken at midday after drinking 0.5 L of water. The main study was conducted among 404 school children (aged 9-12 years) where stool and urine samples were collected for three consecutive days. For S. mansoni diagnosis, stool samples were examined...... for eggs with duplicate Kato-Katz smears, whereas urine samples were tested for presence of antigen by POC-CCA. The proportion of positive individuals for S. mansoni by one POC-CCA was higher compared to two Kato-Katz smears (66.1% vs. 28.7%; p

  13. Distribuição das lesões esquistossomóticas extra-hepáticas em camundongos infectados pelas linhagens BH e SJ do Schistosoma mansoni The distribution of extra-hepatic schistosomotic lesions in mice infected by BH and SJ strains of Schistosoma mansoni

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    Luiz A. Magalhães

    1979-12-01

    Full Text Available Foi estudada a distribuição dos granulomas esquistossomóticos no baço, pulmões, rins, coração e intestinos de camundongos parasitados pelas linhagens BH e SJ de S. mansoni. Verificou-se que a distribuição de granulomas produzidos pelos esquistossomos das duas linhagens é semelhante, sendo que a linhagem BH produziu número significativamente maior de lesões no baço e nos pulmões.The distribution of schisiosomotic granulomae in the spleen, lungs, kidneys, heart, and intestines of mice infected by BH and SJ strains of S. mansoni was studied. No great difference was found in the distribution of granulomae of the two strains; however, the number of lesions caused by the BH strain was greater in the spleen and the lungs.

  14. Estudo dos dados obtidos de uma população de Biomphalaria glabrata de Belo Horizonte infectada por schistosoma mansoni da mesma cidade, e de uma população de B. tenagophila de Campinas. infectada por S. mansoni de São José dos Campos

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    Luiz A. Magalhães

    1969-01-01

    Full Text Available O autor estuda os dados obtidos pela infecção de moluscos de Campinas e de Belo Horizonte por miracídios de S. mansoni. Chega à conclusão de que a população de Belo Horizonte mostrou-se mais susceptível à infecção pelo helminto do que a população de moluscos Campinas.

  15. Structural changes in the jejunal mucosa of mice infected with Schistosoma mansoni, fed low or high protein diets Alterações estruturais na mucosa jejunal de camundongos infectados com Schistosoma mansoni, alimentados com dietas hipo ou hiperprotéicas

    OpenAIRE

    Janira Lúcia Assumpção Couto; Haroldo da Silva Ferreira; Dinalva Bezerra da Rocha; Maria Eugênia Leite Duarte; Monica Lopes de Assunção; Eridan de Medeiros Coutinho

    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...

  16. Hepatic regeneration after partial hepatectomy in mice infected with Schistosoma mansoni, at the acute and chronic phases of the disease Regeneração hepática após hepatectomia parcial em camundongos infectados com Schistosoma mansoni, nas fases aguda e crônica da doença

    OpenAIRE

    Costa, G.(INFN Sezione di Milano, Milan, Italy); J.R. Cunha-Melo; AGUIAR B.G.; Gonçalves, S. C.; TOPPA N.H.; P. M. Z. Coelho

    1999-01-01

    Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65% hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intra...

  17. Biodistribution study of the anesthetic sodium phenobarbital labelled with technetium-99 in swiss mice infected with Schistosoma mansoni Sambon, 1907

    International Nuclear Information System (INIS)

    Technetium-99 m (99m Tc) is a radionuclide that has negligible environmental impact, is easily available, inexpensive and can be used as a radioactive tracer in biological experiences. In order to know the mode of action of sodium phenobarbital in moving adult Schistosoma mansoni worms from mesenteric veins to the liver, we labelled sodium phenobarbital (PBBT) with 99m Tc and a biodistribution study in infected and non-infected Swiss mice was performed. The PBBT was incubated with stannous chloride used as reducing agent and with 99m Tc, as sodium pertechnetate. The radioactivity labelling(%) was determined by paper ascending chromatography performed with acetone (solvent). The99m Tc-PBBT was administered by intraperitoneal route to Swiss mice infected eight weeks before. The animals were perfused after different periods of time (0,1,2,3,4 hr) when blood, spleen, liver, portal vein, mesenteric veins, stomach, kidneys and adult worms were isolated. The radioactivity present in these samples was counted in a well counter and the percentage was determined. THe radioactivity was mainly taken up by the blood, kidney, liver and spleen. No radioactivity was found on the adult worms. We concluded that the worm shift was due to an action on the host of the sodium phenobarbital. (author)

  18. Schistosoma mansoni: radiation dose and morphologic integrity of schistosomules as factors for an effective cryopreserved live vaccine

    International Nuclear Information System (INIS)

    The effectiveness of a cryopreserved, irradiated schistosomule vaccine against an homologous Schistosoma mansoni cercarial challenge was tested in C57B1/6 mice. Highly significant levels of protection developed consistently when mice were immunized with the vaccine irradiated at 10-20 Krad, i.e., doses below that considered optimal for irradiated cercariae (50 Krad). Cryopreserved schistosomules irradiated at 10 or 20 Krad induced greater levels of protection than did schistosomules irradiated at 2, 5, 30, or 50 Krad. Protective immunity developed as early as 3 weeks post-immunization. When immunizing inocula were injected at various times post-thaw, or when schistosomule subpopulations of normal-appearing, damaged or dead organisms were injected, those populations which had appeared to sustain the least degree of damage were those most capable of stimulating protective immunity. These findings highlight the hazards of extrapolating conditions considered standard for an irradiated cercarial vaccine to one in which cryopreservation, for storage of the schistosomules, is an added stress

  19. Schistogram changes after administration of antischistosomal drugs in mice at the early phase of Schistosoma mansoni infection

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    Andrea Cassia Simoes Vimieiro

    2013-11-01

    Full Text Available Mice infected with Schistosoma mansoni were treated with oxamniquine, praziquantel, artesunate at the pre-patent phase, aiming at observing schistogram alterations. Half of the animals were perfused five days post-treatment for counting and classification of immature worms, based on pre-established morphological criteria (schistogram; the remaining animals were evaluated 42 or 100 days after infection and perfusion of the portal-system was performed for collection and counting of adult worms and oogram. It was observed that oxamniquine and artesunate treatment administered at the pre-postural phase causes significant reduction in the number of immature and adult worms. However, there was little reduction with praziquantel when used at the dose of 400 mg/kg for treatments administered 14, 15, 21 or 23 days post-infection. Artesunate was responsible for significant alterations in development of young worms, as well as for a higher number of worms presenting intestinal damages. Immature adult worms were detected in mice treated with artesunate or oxamniquine at the pre-patent phase of infection and recovered by perfusion 100 days after infection. Schistogram proved to be a very useful tool for experimental evaluation of the activity of antischistosomal drugs and a good model to identify the most sensitive stages to drugs.

  20. Factors associated with Schistosoma mansoni infection 5 years after selective treatment in a low endemic area in Brazil.

    Science.gov (United States)

    Disch, Jolande; Katz, Naftale; Pereira e Silva, Yerkes; de Gouvêa Viana, Luciana; Andrade, Marcela Orsini; Rabello, Ana

    2002-02-01

    Five years after a single dose treatment, prevalence, intensity and morbidity of schistosomiasis mansoni were evaluated in Agua Branca, a low endemic community in the South East Brazil (cure rate 94%). At community level, prevalence showed a decrease from 38.9 to 24.5% and the intensity of infection dropped from 119.5 to 38.9 eggs per g of faeces (epg). However, after the exclusion of immigrants, newborn children and individuals that had left the area after the first evaluation, the prevalence among the treated and followed population was not significantly affected. Multivariate analysis showed that the 10-29 age group and water contact for agricultural purposes were independently associated with the presence of infection on post treatment evaluation [OR 3.9 and 5.09, respectively]. A previous treatment among subjects older than 15 years was inversely associated [OR 0.58]. The authors wish to draw attention to the fact that mobility may lead to a serious bias in evaluating the impact of the control programme. PMID:11801220

  1. Estudo imunológico da esquistossomose mansoni intestinal antes e após tratamento com aminonitrotiazol

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    Lucyr Jones Antunes

    1974-02-01

    Full Text Available Foram dosadas as imunoglobulinas e realizados testes cutâneos para se avaliar o sistema imunológico de pacientes portadores da forma intestinal da esquistossomose mansoni. Estes testes foram realizados antes do tratamento com aminonitrotiazol e após trinta, sessenta e noventa dias do tratamento. Antes do tratamento o nível de IgG (1893 ± 472 mg% apresentava-se elevado, mas os níveis de IgA (186 ± 74 mg% e de IgM (91 ± 26 mg% achavam-se normais. Decorridos trinta, sessenta e noventa dias do tratamento, o nível de IgG diminuiu, observando-se ligeira elevação de IgA bem como de IgM. Os pacientes, antes do tratamento, quando testados com schistosomina e anti IgE apresentaram áreas de 1,22 ± 0,36 cm² e 1,04 ± 0,25 cm², respectivamente. Noventa dias após o tratamento, as reações à schistosomina e ao soro anti IgE produziram reações com áreas ainda maiores. Os testes de hipersensibilidade retardada mostraram que 35% dos pacientes reagiram à schistosomina e 71% ao 2-4 dinitrofluorobenzeno.

  2. Comportamento da cepa LE de Schistosoma mansoni, após passagem em hospedeiro humano infectado acidentalmente

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    Neusa Araújo

    1986-12-01

    Full Text Available Uma auxiliar de laboratório infectou-se acidentalmente, com cercárias de Schistosoma mansoni, cepa LE, mantida rotineiramente em nossos laboratórios. Decorridos 5 meses, o exame parasitológico de fezes revelou 108 ovos/g . A pacientefoi tratada com oxamniquine, porém a infecção continuou ativa (6 ovos/g. Foi então obtido o isolado SSF mantido no modelo Biomphalaria glabrata - camundongo albino. Os resultados obtidos no estudo comparativo, entre o isolado SSF e a cepa LE, que lhe deu origem, mostraram que a duração do período pré-patente e o índice de infectividade em camundongos, bem como a resposta aos agentes esquistossomicidas (hycanthone, oxamniquine epraziquantel não apresentaram diferenças estatisticamente significativas. Por outro lado, o número de miracídios obtidos dos intestinos e fígados dos camundongos infectados foi o dobro com a cepa LE, quando comparados com aquele do isolado SSF. Também a variação do peso dos animais foi bastante diferente. Concluiu-se que apenas uma passagem pelo hospedeiro humano não mudou substancialmente as características da cepa estudada.

  3. Quantum mechanics-based scoring rationalizes the irreversible inactivation of parasitic Schistosoma mansoni cysteine peptidase by vinyl sulfone inhibitors.

    Science.gov (United States)

    Fanfrlík, Jindřich; Brahmkshatriya, Pathik S; Řezáč, Jan; Jílková, Adéla; Horn, Martin; Mareš, Michael; Hobza, Pavel; Lepšík, Martin

    2013-12-01

    The quantum mechanics (QM)-based scoring function that we previously developed for the description of noncovalent binding in protein-ligand complexes has been modified and extended to treat covalent binding of inhibitory ligands. The enhancements are (i) the description of the covalent bond breakage and formation using hybrid QM/semiempirical QM (QM/SQM) restrained optimizations and (ii) the addition of the new ΔG(cov)' term to the noncovalent score, describing the "free" energy difference between the covalent and noncovalent complexes. This enhanced QM-based scoring function is applied to a series of 20 vinyl sulfone-based inhibitory compounds inactivating the cysteine peptidase cathepsin B1 of the Schistosoma mansoni parasite (SmCB1). The available X-ray structure of the SmCB1 in complex with a potent vinyl sulfone inhibitor K11017 is used as a template to build the other covalently bound complexes and to model the derived noncovalent complexes. We present the correlation of the covalent score and its constituents with the experimental binding data. Four outliers are identified. They contain bulky R1' substituents structurally divergent from the template, which might induce larger protein rearrangements than could be accurately modeled. In summary, we propose a new computational approach and an optimal protocol for the rapid evaluation and prospective design of covalent inhibitors with a conserved binding mode. PMID:24195769

  4. Schistosoma mansoni: quantitative aspects of the fertility and survival of worms obtained from irradiated cercariae (3 Krad), in mice

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the fertility of female mice, as well as the survival of worms in their portal system, have been observed in four groups of outbred albino mice (Mus musculus), experimentally infected with ca 450 cercariae of Schistosoma mansoni (LE and SJ strains), by transcutaneous route. The cercariae used were a) non-irradiated (control groups), and b) irradiated with 3 Krad of gamma irradiation (Co-60). From the 33rd day on, some stability in the population of surviving worm could be observed. This population remained constant till the end of the observation period (90th day), notedly in relation to the LE strain . Thus, it was concluded that gamma irradiation (at the dose of 3 Krad) is able to hinder the worm egg production in 98.1% of the infected mice. Further, it was observed that the few detected eggs were dead. Females were found to be more resistant to irradiation. The irradiation effect on the mortality of male worms was statistically significant scarcely from the 61st day on. The long period of permanence of the sterile adult irradiated worms in the portal system of mice and their probable involvement in the development of immuno-protection (the so-called concomitant immunity, without the immuno-pathological involvements for the host) are here discussed. (author)

  5. Cloning of a cDNA encoding a surface antigen of Schistosoma mansoni schistosomula recognized by sera of vassinated mice

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, J.P.; Tom, T.D.; Strand, M.

    1987-06-01

    Spleen cells of mice vaccinated with radiation-attenuated Schistosoma mansoni cercariae were used to produce monoclonal antibodies directed against newly transformed schistosomular surface antigens. One of these monoclonal antibodies recognized a polypeptide of 18 kDa. Binding was measured by radioimmunoassay. This glycoprotein was purified by monoclonal antibody immunoaffinity chromatography and a polyclonal antiserum was prepared against it. Immunofluorescence assays showed that the polyclonal antiserum bound to the surface of newly transformed schistosomula and lung-stage organisms but not to the surface of liver-stage and adult worms. Using this polyclonal antiserum we isolated recombinant clones from an adult worm cDNA expression library constructed in lambdagt11. Clone 654.2 contained an insert of 0.52 kilobase and hybridized to a 1.2-kilobase mRNA species from adult worms. Most importantly, clone 654.2 produced a fusion protein of 125 kDa that was reactive with sera of vaccinated mice that are capable of transferring resistance. This result encourages future vaccination trials with the fusion protein.

  6. The magnitude and kinetics of delayed-type hypersensitivity responses in mice vaccinated with irradiated cercariae of Schistoma mansoni

    Energy Technology Data Exchange (ETDEWEB)

    Ratcliffe, E.C.; Wilson, R.A. (York Univ. (United Kingdom). Dept. of Biology)

    1991-08-01

    A footpad assay was used to measure the DTH of mice to soluble worm antigens (SWAP), and to living day 7 lung schistosomula, following vaccination and challenge infections with Schistosoma mansoni. DTH to SWAP was first observed on day 10, and reached its maximum on day 17 post-vaccination. Treatment of mice with anti-CD4 antibody on the 3 days prior to footpad challenge completely abrogated this response. Reactivity to living parasites was of a slower order than that to SWAP; it also peaked earlier, on day 10 post-vaccination. By day 35, responsiveness to both sets of antigens had declined almost to control levels. There was no correlation between the level of DTH to living schistosomula, at any time, and the degree of resistance subsequently developed. Percutaneous challenge of vaccinated mice was followed by a resurgence of reactivity to SWAP. This secondary response occurred more rapidly than the primary response, peaking on day 7 post-challenge, and was of a similar magnitude. We were unable to detect a similar recall of DTH to living schistosomula, possibly because the assay was insufficiently sensitive. We conclude that the intensity and kinetics of DTH responsiveness are crucial features of the irradiated vaccine model, and suggest that further investigation of cell-mediated immune reaction, particularly those occuring in the lungs, is vital to a better understanding of events underlying the development and expression of immunity. (author).

  7. Biodistribution study of the anesthetic sodium phenobarbital labelled with technetium-99 in swiss mice infected with Schistosoma mansoni Sambon, 1907

    Energy Technology Data Exchange (ETDEWEB)

    Simoes, Susana Balmant Emerique; Machado Silva, Jose Roberto [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Faculdade de Ciencias Medicas. Dept. de Patologia e Laboratorios; Gutfilen, Bianca; Oliveira, Marcia Betania; Bernardo Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria; Presgrave, Otavio Augusto Franca [Fundacao Inst. Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Inst. Nacional de de Controle de Qaulidade em Saude. Dept. de Farmacologia e Toxicologia

    1997-09-01

    Technetium-99 m ({sup 99m} Tc) is a radionuclide that has negligible environmental impact, is easily available, inexpensive and can be used as a radioactive tracer in biological experiences. In order to know the mode of action of sodium phenobarbital in moving adult Schistosoma mansoni worms from mesenteric veins to the liver, we labelled sodium phenobarbital (PBBT) with {sup 99m} Tc and a biodistribution study in infected and non-infected Swiss mice was performed. The PBBT was incubated with stannous chloride used as reducing agent and with {sup 99m} Tc, as sodium pertechnetate. The radioactivity labelling(%) was determined by paper ascending chromatography performed with acetone (solvent). The{sup 99m} Tc-PBBT was administered by intraperitoneal route to Swiss mice infected eight weeks before. The animals were perfused after different periods of time (0,1,2,3,4 hr) when blood, spleen, liver, portal vein, mesenteric veins, stomach, kidneys and adult worms were isolated. The radioactivity present in these samples was counted in a well counter and the percentage was determined. THe radioactivity was mainly taken up by the blood, kidney, liver and spleen. No radioactivity was found on the adult worms. We concluded that the worm shift was due to an action on the host of the sodium phenobarbital. (author) 24 refs., 3 tabs.

  8. Humoral and cellular immune responses induced in mice by purified iridoid mixture that inhibits penetration of Schistosoma mansoni cercariae upon topical treatment of mice tails.

    Science.gov (United States)

    Bahgat, Mahmoud; Shalaby, Nagwa M M; Ruppel, Andreas; Maghraby, Amany S

    2005-08-01

    When tested for possible blocking effect on the cercarial, serine proteinase, elastase (CE) activity, an iridoid mixture extracted from leaves of Citharexylum quadrangular abolished 31% of the enzyme activity at final concentration 15 microg. When formulated in jojoba oil and applied to mice tails followed by infection with Schistosoma mansoni cercariae, the iridoid mixture blocked cercarial penetration and caused significant reducetion (94%; P < 0.05) in worm burden in treated mice in comparison to controls. Also, immunomodulatory effects of iridoid mixture, iridoid-treated S. mansoni worm homogenate on mice were studied by measuring IgG and IgM levels against E. coli lysates (ECL), solube S. mansoni worm antigenic preparation (SWAP) and cancer bladder homogenates (CBH) as antigens by ELISA. Cellular immune responses were studied by calculating mean percent of CD4+, CD8(+)-T, B-mesenteric lymph node cells (MLNC) and CD4+, CD8(+)-T thymocytes by direct immunofluorescence staining in treated mice as compared to untreated homogenate given mice or untreated mice. Injecting mice with serial dilutions of iridoid mixture resulted in fluctuation, peaks and troughs, in both IgG and IgM responses against the above mentioned antigens. 1st and 2nd immunizations with iridoid mixture treated homogenate resulted in significantly elevated (P < 0.05). IgM and IgG levels against the 3 used antigens in comparison with sera from control mice. Immunized mice with homogenate treated with iridoid mixture showed a significant increase (P < 0.05) in CD4+T thymocytes, a non significant increase in CD8+T thymocytes, a significant increase (P < 0.05) in CD4+T lymphocytes (MLNC) and a non significant increase in CD8+ T- and B-lymphocytes (MLNC) compared with mice immunized with untreated homogenate or non-injected normal mice.

  9. In vitro evaluation of schistosomicidal activity of essential oil of Mentha x villosa and some of its chemical constituents in adult worms of Schistosoma mansoni.

    Science.gov (United States)

    Matos-Rocha, Thiago José; dos Santos Cavalcanti, Marília Gabriela; Barbosa-Filho, José Maria; Lúcio, Ana Silvia Suassuna Carneiro; Veras, Dyana Leal; Feitosa, Ana Paula Sampaio; de Siqueira Júnior, José Pinto; de Almeida, Reinaldo Nóbrega; Marques, Márcia Ortiz Mayo; Alves, Luiz Carlos; Brayner, Fábio André

    2013-09-01

    This study aimed to determine the composition of the essential oil of Mentha x villosa and to evaluate its biological effects in vitro on adult worms of S. mansoni. Rotundifolone (70.96 %), limonene (8.75 %), trans-caryophyllene (1.46 %), and β-pinene (0.81 %) were shown to be the major constituents of this oil. Adult worms of S. mansoni were incubated with different concentrations of the essential oil (1, 10, 100, 250, 500, and 1000 µg/mL) and of its constituents rotundifolone (0.7, 3.54, 7.09, 70.96, 177.4, 354.8, and 700.96 µg/mL), limonene (43.75 µg/mL), trans-caryophyllene (7.3 µg/mL), and β-pinene (4.03 µg/mL). No schistosomicidal activity was identified at the trans-caryophyllene and β-pinene concentrations studied. However, use of the essential oil (10 µg/mL), rotundifolone (7.09 µg/mL), and limonene (43.75 µg/mL) resulted in decreased worm motility continuing until 96 hours of observation. At higher concentrations (100 and 70.96 µg/mL, respectively), both the essential oil and rotundifolone caused mortality among adult worms of S. mansoni. The positive control praziquantel caused the death of all parasites after 24 h of evaluation. The results from this study suggest that the essential oil of Mentha x villosa presents schistosomicidal efficacy.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Artesunate Effect on Schistosome Thioredoxin Glutathione Reductase and Cytochrome c Peroxidase as New Molecular Targets in Schistosoma mansoni-infected Mice

    Institute of Scientific and Technical Information of China (English)

    Amany A.Abdin; Dalia S.Ashour; Zeinab S.Shoheib

    2013-01-01

    Objective To investigate the possible effect of artesunate (ART) on schistosome thioredoxin glutathione reductase (TGR) and cytochrome c peroxidase (CcP) in Schistosoma mansoni-infected mice. Methods A total of 200 laboratory bred male Swiss albino mice were divided into 4 groups (50 mice in each group). Group I:infected untreated group (Control group) received a vehicle of 1%sodium carbonyl methylcellulose (CMC-Na); Group II: infected then treated with artesunate; Group III: infected then treated with praziquantel, and group IV:infected then treated with artesunate then praziquantel. Adult S. mansoni worms were collected by Animal Perfusion Method, tissue egg counted, TGR, and CcP mRNA Expression were estimated of in S. mansoni adult worms by semi-quantitative rt-PCR. Results Semi-quantitative rt-PCR values revealed that treatment with artesunate caused significant decrease in expression of schistosome TGR and CcP in comparison to the untreated group. In contrast, the treatment with praziquantel did not cause significant change in expression of these genes. The results showed more reduction in total worm and female worm count in combined ART-PZQ treated group than in monotherapy treated groups by either ART or PZQ. Moreover, complete disappearance (100%) of tissue eggs was recorded in ART-PZQ treated group with a respective reduction rate of 95.9%and 68.4%in ART-and PZQ-treated groups. Conclusion The current study elucidated for the first time that anti-schistosomal mechanisms of artesunate is mediated via reduction in expression of schistosome TGR and CcP. Linking these findings, addition of artesunate to praziquantel could achieve complete cure outcome in treatment of schistosomiasis.

  12. Comparative efficacy of one versus two doses of praziquantel on cure rate of Schistosoma mansoni infection and re-infection in Mayuge District, Uganda

    DEFF Research Database (Denmark)

    Tukahebwa, Edridah M.; Vennervald, Birgitte J; Nuwaha, Fred;

    2013-01-01

    BACKGROUND: The current recommended control strategy for schistosomiasis is annual treatment using 40 mg/kg of praziquantel. However, praziquantel is only effective on adult worms and giving a second dose may increase its efficacy. We assessed the effect of one versus two doses of praziquantel on...... months after treatment. RESULTS: Those who received two doses were more likely to be cured (69.7%) compared to those who received a single dose (47.9%) (¿(2) = 18.5, p ... intensity. However, there is no added advantage on reduction of S. mansoni re-infection by administering two doses of praziquantel. CLINICAL TRIALS.GOV IDENTIFIER: NCT00215267....

  13. Multivariable Regression Analysis in Schistosoma mansoni-Infected Individuals in the Sudan Reveals Unique Immunoepidemiological Profiles in Uninfected, egg+ and Non-egg+ Infected Individuals.

    Directory of Open Access Journals (Sweden)

    Tayseer Elamin Mohamed Elfaki

    2016-05-01

    Full Text Available In the Sudan, Schistosoma mansoni infections are a major cause of morbidity in school-aged children and infection rates are associated with available clean water sources. During infection, immune responses pass through a Th1 followed by Th2 and Treg phases and patterns can relate to different stages of infection or immunity.This retrospective study evaluated immunoepidemiological aspects in 234 individuals (range 4-85 years old from Kassala and Khartoum states in 2011. Systemic immune profiles (cytokines and immunoglobulins and epidemiological parameters were surveyed in n = 110 persons presenting patent S. mansoni infections (egg+, n = 63 individuals positive for S. mansoni via PCR in sera but egg negative (SmPCR+ and n = 61 people who were infection-free (Sm uninf. Immunoepidemiological findings were further investigated using two binary multivariable regression analysis.Nearly all egg+ individuals had no access to latrines and over 90% obtained water via the canal stemming from the Atbara River. With regards to age, infection and an egg+ status was linked to young and adolescent groups. In terms of immunology, S. mansoni infection per se was strongly associated with increased SEA-specific IgG4 but not IgE levels. IL-6, IL-13 and IL-10 were significantly elevated in patently-infected individuals and positively correlated with egg load. In contrast, IL-2 and IL-1β were significantly lower in SmPCR+ individuals when compared to Sm uninf and egg+ groups which was further confirmed during multivariate regression analysis.Schistosomiasis remains an important public health problem in the Sudan with a high number of patent individuals. In addition, SmPCR diagnostics revealed another cohort of infected individuals with a unique immunological profile and provides an avenue for future studies on non-patent infection states. Future studies should investigate the downstream signalling pathways/mechanisms of IL-2 and IL-1β as potential diagnostic markers

  14. Biomphalaria glabrata transcriptome: cDNA microarray profiling identifies resistant- and susceptible-specific gene expression in haemocytes from snail strains exposed to Schistosoma mansoni

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    Rollinson David

    2008-12-01

    Full Text Available Abstract Background Biomphalaria glabrata is an intermediate snail host for Schistosoma mansoni, one of the important schistosomes infecting man. B. glabrata/S. mansoni provides a useful model system for investigating the intimate interactions between host and parasite. Examining differential gene expression between S. mansoni-exposed schistosome-resistant and susceptible snail lines will identify genes and pathways that may be involved in snail defences. Results We have developed a 2053 element cDNA microarray for B. glabrata containing clones from ORESTES (Open Reading frame ESTs libraries, suppression subtractive hybridization (SSH libraries and clones identified in previous expression studies. Snail haemocyte RNA, extracted from parasite-challenged resistant and susceptible snails, 2 to 24 h post-exposure to S. mansoni, was hybridized to the custom made cDNA microarray and 98 differentially expressed genes or gene clusters were identified, 94 resistant-associated and 4 susceptible-associated. Quantitative PCR analysis verified the cDNA microarray results for representative transcripts. Differentially expressed genes were annotated and clustered using gene ontology (GO terminology and Kyoto Encyclopaedia of Genes and Genomes (KEGG pathway analysis. 61% of the identified differentially expressed genes have no known function including the 4 susceptible strain-specific transcripts. Resistant strain-specific expression of genes implicated in innate immunity of invertebrates was identified, including hydrolytic enzymes such as cathepsin L, a cysteine proteinase involved in lysis of phagocytosed particles; metabolic enzymes such as ornithine decarboxylase, the rate-limiting enzyme in the production of polyamines, important in inflammation and infection processes, as well as scavenging damaging free radicals produced during production of reactive oxygen species; stress response genes such as HSP70; proteins involved in signalling, such as importin 7

  15. Micro-geographical variation in exposure to Schistosoma mansoni and malaria, and exacerbation of splenomegaly in Kenyan school-aged children

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    Kimani Gachuhi

    2004-05-01

    Full Text Available Abstract Background Schistosoma mansoni and Plasmodium falciparum are common infections of school aged childr