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Sample records for block schistosoma japonicum

  1. Taxonomy Icon Data: Schistosoma japonicum [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available .png Schistosoma_japonicum_NL.png Schistosoma_japonicum_S.png Schistosoma_japonicum_NS.png http://biosciencedbc.jp/taxonomy..._icon/icon.cgi?i=Schistosoma+japonicum&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=S...chistosoma+japonicum&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schist...osoma+japonicum&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Schistosoma+japonicum&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=132 ...

  2. A novel coagulation inhibitor from Schistosoma japonicum.

    Science.gov (United States)

    Ranasinghe, Shiwanthi L; Fischer, Katja; Gobert, Geoffrey N; McManus, Donald P

    2015-12-01

    Little is known about the molecular mechanisms whereby the human blood fluke Schistosoma japonicum is able to survive in the host venous blood system. Protease inhibitors are likely released by the parasite enabling it to avoid attack by host proteolytic enzymes and coagulation factors. Interrogation of the S. japonicum genomic sequence identified a gene, SjKI-1, homologous to that encoding a single domain Kunitz protein (Sjp_0020270) which we expressed in recombinant form in Escherichia coli and purified. SjKI-1 is highly transcribed in adult worms and eggs but its expression was very low in cercariae and schistosomula. In situ immunolocalization with anti-SjKI-1 rabbit antibodies showed the protein was present in eggs trapped in the infected mouse intestinal wall. In functional assays, SjKI-1 inhibited trypsin in the picomolar range and chymotrypsin, neutrophil elastase, FXa and plasma kallikrein in the nanomolar range. Furthermore, SjKI-1, at a concentration of 7·5 µ m, prolonged 2-fold activated partial thromboplastin time of human blood coagulation. We also demonstrate that SjKI-1 has the ability to bind Ca(++). We present, therefore, characterization of the first Kunitz protein from S. japonicum which we show has an anti-coagulant properties. In addition, its inhibition of neutrophil elastase indicates SjKI-1 have an anti-inflammatory role. Having anti-thrombotic properties, SjKI-1 may point the way towards novel treatment for hemostatic disorders. PMID:26463744

  3. Transmission dynamics of Schistosoma japonicum in the lakes and marshlands of China.

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    Darren J Gray

    Full Text Available BACKGROUND: Schistosoma japonicum is a major public health concern in China, with over one million people infected and another 40 million living in areas at risk of infection. Unlike the disease caused by S. mansoni and S. haematobium, schistosomiasis japonica is a zoonosis, involving a number of different mammalian species as reservoir hosts. As a result of a number of published reports from China, it has long been considered that bovines, particularly water buffaloes, play a major role in human S. japonicum transmission there, and a drug-based intervention study (1998-2003 around the Poyang Lake in Jiangxi Province provided proof of concept that water buffaloes are, indeed, major reservoirs of human infection in this setting. METHODS AND FINDINGS: In this study we incorporated recently obtained epidemiological information to model the steady-state S. japonicum transmission as well as the impact of the removal of S. japonicum transmission attributable to water buffaloes on human infection rates across six different endemic scenarios within three villages in the Dongting (Hunan and Poyang (Jiangxi lakes of southern China. Similar results were obtained for all scenarios. Steady-state S. japonicum infection rates remained constant and human prevalence and incidence were predicted to fall considerably over time. The model showed that the contribution of S. japonicum water buffalo transmission to human infection ranged from 39.1% to 99.1% and predicted that the removal of water buffalo transmission would reduce parasite reproductive rates below 1. This indicates that without the contribution of water buffaloes, S. japonicum transmission is interrupted and unsustainable. These scenarios are generalizable to other endemic villages in the lake and marshland areas of China where a similar cycle of snail infection and infection/reinfection of humans and bovines occurs. CONCLUSIONS: Along with previous epidemiological data, our findings strongly support

  4. Synthesis and SAR Studies of Praziquantel Derivatives with Activity against Schistosoma japonicum

    OpenAIRE

    Chuan-Xin Yu; Bainian Feng; Wen-Hua Fan; Gu-Ping Wang; Xu-Ren Yin; Xia Chen; Li-Jun Song; Wen-Long Wang

    2013-01-01

    The synthesis and structure-activity relationship (SAR) studies of praziquantel derivatives with activity against adult Schistosoma japonicum are described. Several of them showed better worm killing activity than praziquantel and could serve as leads for further optimization.

  5. A REVIEW OF SCHISTOSOMIASIS IN INDONESIA WITH REFERENCE TO SCHISTOSOMA JAPONICUM

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    Lim Boo Liat

    2012-09-01

    Full Text Available Tinjauan tentang Schistosoma di Indonesia ini mencakup Schistosoma japonicum, S. incognitum, S. spindale dan Trichohilharzia brevis. Tinjauan dibuat atas dasar laporan-laporan penelitian yang telah diterbitkan. Di dalamnya dapat dijumpai uraian singkat tentang S. spinale dan T. brevis. Dari banyak publikasi tentang S. japonicum dan S. incoganitum dapat disajikan uraian tentang peranan kedua parasit tersebut sebagai penyebab penyakit baik manusia maupun hewan.

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

    DEFF Research Database (Denmark)

    Techau, Michala E.; Johansen, Maria V.; Aasted, Bent; Lind, Peter; Ornbjerg, Niel; Oswald, Isabelle P.

    2007-01-01

    The pig is a natural host for Schistosoma japonicum and a useful animal model of human infection. The aim of the present study was to assess the differences between the cytokine profiles in prenatally or postnatally S. japonicum exposed pigs. Seven prenatally exposed pigs, 7 postnatally exposed p...

  7. Cloning and characterisation of Schistosoma japonicum insulin receptors.

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    Hong You

    Full Text Available BACKGROUND: Schistosomes depend for growth and development on host hormonal signals, which may include the insulin signalling pathway. We cloned and assessed the function of two insulin receptors from Schistosoma japonicum in order to shed light on their role in schistosome biology. METHODOLOGY/PRINCIPAL FINDINGS: We isolated, from S. japonicum, insulin receptors 1 (SjIR-1 and 2 (SjIR-2 sharing close sequence identity to their S. mansoni homologues (SmIR-1 and SmIR-2. SjIR-1 is located on the tegument basal membrane and the internal epithelium of adult worms, whereas SjIR-2 is located in the parenchyma of males and the vitelline tissue of females. Phylogenetic analysis showed that SjIR-2 and SmIR-2 are close to Echinococcus multilocularis insulin receptor (EmIR, suggesting that SjIR-2, SmIR-2 and EmIR share similar roles in growth and development in the three taxa. Structure homology modelling recovered the conserved structure between the SjIRs and Homo sapiens IR (HIR implying a common predicted binding mechanism in the ligand domain and the same downstream signal transduction processing in the tyrosine kinase domain as in HIR. Two-hybrid analysis was used to confirm that the ligand domains of SjIR-1 and SjIR-2 contain the insulin binding site. Incubation of adult worms in vitro, both with a specific insulin receptor inhibitor and anti-SjIRs antibodies, resulted in a significant decrease in worm glucose levels, suggesting again the same function for SjIRs in regulating glucose uptake as described for mammalian cells. CONCLUSIONS: Adult worms of S. japonicum possess insulin receptors that can specifically bind to insulin, indicating that the parasite can utilize host insulin for development and growth by sharing the same pathway as mammalian cells in regulating glucose uptake. A complete understanding of the role of SjIRs in the biology of S. japonicum may result in their use as new targets for drug and vaccine development against

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

    International Nuclear Information System (INIS)

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

  9. Schistosoma japonicum-like ova in liver and rectal biopsies of three cases in Sabah, Malaysia.

    Science.gov (United States)

    Kan, S K; Kay, R W; Thomas, I

    1979-03-01

    Three cases of schistosomiasis in 2 Filipinos and one Chinese in Sabah are reported. Diagnosis was based on incidental histological findings of Schistosoma japonicum-like ova in the liver and rectal biopsies. As these 3 patients are immigrants to Sabah, it is assumed that they are imported cases, and that Sabah has been free of the disease from 1970 to 1977. PMID:573502

  10. Congenital infection of rabbits with Schistosoma japonicum and protective immunity of offspring

    Institute of Scientific and Technical Information of China (English)

    SHI You-en 石佑恩; Abdel-Moneim M Salim 沙里模; NING Chang-xiu 宁长修; GAN Yan 甘燕; ZHU Xiao-hua 朱晓华; PU Ling-yi 卜玲毅

    2004-01-01

    Background Recently congenital infection with Schistosoma japonicum (S. Japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schistosomiasis japonica and assessed the effect of a congenital S. Japonicum infection on the resistance of rabbit kittens to a postnatal challenge infection.Methods Sixteen pregnant New Zealand white rabbits were infected with a single dose of S. Japonicum cercariae. The exposed animals were divided into three groups according to the gestation age at the time of infection. Diagnosis of prenatally acquired S. Japonicum infection in the rabbit kittens was primarily based on serological tests in combination with parasitological and histopathological findings. Congenitally infected kittens were challenged percutaneously with 100 S. Japonicum cercariae to assess the effect of a congenital S. Japonicum infection on kitten resistance to a postnatal challenge infection.Conclusions This study demonstrates the possibility of congenital infection of S. Japonicum in rabbits and the resistance of congenitally infected kittens to a postnatal challenge infection. These results have important implications not only for epidemiological investigations, but also in designing government control programs for schistosomiasis.

  11. Comparison of worm development and host immune responses in natural hosts of schistosoma japonicum, yellow cattle and water buffalo

    OpenAIRE

    Yang Jianmei; Fu Zhiqiang; Feng Xingang; Shi Yaojun; Yuan Chunxiu; Liu Jinming; Hong Yang; Li Hao; Lu Ke; Lin Jiaojiao

    2012-01-01

    Abstract Background Yellow cattle and water buffalo are two of the most important natural hosts for Schistosoma japonicum in China. Previous observation has revealed that yellow cattle are more suited to the development of S. japonicum than water buffalo. Understanding more about the molecular mechanisms involved in worm development, as well as the pathological and immunological differences between yellow cattle and water buffalo post infection with S japonicum will provide useful information...

  12. Mice lack of LRG-47 display the attenuated outcome of infection with Schistosoma japonicum.

    Science.gov (United States)

    Gao, Yanan; Wu, Jingjiao; Zhang, Meijuan; Hou, Min; Ji, Minjun

    2016-03-01

    Interferon-inducible GTPase LRG-47 (also named immune-related GTPase M, Irgm1) is a member of the p47 GTPase family that has been shown to regulate host resistance to intracellular pathogens. Little knowledge has been known about the role of LRG-47 in host's responses to extracellular pathogens. To investigate possible roles of LRG-47 in the course of Schistosoma japonicum infection, LRG-47-deficient (LRG-47(-/-)) and wild-type (WT) mice were challenged with cercariae of S. japonicum, and the cellular and humoral responses in mice were analyzed. At the acute stage of S. japonicum infection, in contrast to WT mice, LRG-47(-/-) mice showed the significantly decreased egg burden, low schistosome-specific antibody response, and the decreased Th1 and increased Tc1 responses. Additionally, Schistosoma japonicum-specific egg antigen immunization also produced the similar humoral and cellular immune responses as S. japonicum infection. Taken together, these data suggested that the deficiency of LRG-47 might affect host's CD4(+) T cell immune response via the weakening of IFN-γ downstream signaling; however, the specific function of LRG-47 on dealing with extracellular worm needs to be further studied. PMID:26660918

  13. Quantitative Detection of Schistosoma japonicum Cercariae in Water by Real-Time PCR

    OpenAIRE

    Hung, Yuen Wai; Remais, Justin

    2008-01-01

    In China alone, an estimated 30 million people are at risk of schistosomiasis, caused by the Schistosoma japonicum parasite. Disease has re-emerged in several regions that had previously attained transmission control, reinforcing the need for active surveillance. The environmental stage of the parasite is known to exhibit high spatial and temporal variability, and current detection techniques rely on a sentinel mouse method which has serious limitations in obtaining data in both time and spac...

  14. The Schistosoma japonicum genome reveals features of host-parasite interplay

    OpenAIRE

    Zhou, Yan; Zheng, Huajun; Chen, Xiangyi; Zhang, Lei; WANG Kai; Guo, Jing; Huang, Zhen; Zhang, Bo; Huang, Wei; Jin, Ke; Tonghai, Dou; Hasegawa, Masami; Wang, Li; Zhang, Yuan; Zhou, Jie

    2009-01-01

    Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, a significant cause of morbidity in China and the Philippines. Here we present a draft genomic sequence for the worm, which is the first reported for any flatworm, indeed for the superphylum Lophotrochozoa. The genome provides a global insight into the molecular architecture and host interaction of this complex metazoan pathogen, revealing that it can exploit host nutrients, neuroendocrine hormones and signaling ...

  15. Transcriptome Bioinformatical Analysis of Vertebrate Stages of Schistosoma japonicum Reveals Alternative Splicing Events

    OpenAIRE

    Xinye Wang; Xindong Xu; Xingyu Lu; Yuanbin Zhang; Weiqing Pan

    2015-01-01

    Alternative splicing is a molecular process that contributes greatly to the diversification of proteome and to gene functions. Understanding the mechanisms of stage-specific alternative splicing can provide a better understanding of the development of eukaryotes and the functions of different genes. Schistosoma japonicum is an infectious blood-dwelling trematode with a complex lifecycle that causes the tropical disease schistosomiasis. In this study, we analyzed the transcriptome of Schistoso...

  16. The characteristics of NK cells in Schistosoma japonicum-infected mouse spleens.

    Science.gov (United States)

    Li, Lu; Cha, Hefei; Yu, Xiuxue; Xie, Hongyan; Wu, Changyou; Dong, Nuo; Huang, Jun

    2015-12-01

    Natural killer (NK) cells are classic innate immune cells that play roles in many types of infectious disease. Recently, some new characteristics of NK cells were discovered. In this study, C57BL/6 mice were infected with Schistosoma japonicum for 5-6 weeks and lymphocytes were isolated from the spleen to detect some of the NK cell characteristics by multiparametric flow cytometry. The results revealed that the S. japonicum infection induced a large amount of NK cells, although the percentage of NK cells was not increased significantly. At the same time, the results showed that infected mouse splenic NK cells expressed increased levels of CD25 and CD69 and produced more IL-2, IL-4, and IL-17 and less IFN-γ after stimulation with PMA and ionomycin. This meant that NK cells played a role in S. japonicum infection. Moreover, decreased NKG2A/C/E (CD94) expression levels were detected on the surface of NK cells from infected mouse spleens, which might serve as a NK cell activation mechanism. Additionally, high levels of IL-10, but not PD-1, were expressed on the infected mouse NK cells, which implied that functional exhaustion might exist in the splenic NK cells from S. japonicum-infected mice. Collectively, our results suggest that NK cells play important roles in the course of S. japonicum infection. PMID:26319521

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

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    Feng Liu

    2006-04-01

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

  18. INFEKSI Schistosoma japonicum PADA HOSPES RESERVOIR TIKUS DI DATARAN TINGGI NAPU, KABUPATEN POSO, SULAWESI TENGAH TAHUN 2012

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    Made Agus Nurjana

    2013-11-01

    Full Text Available Abstrak Tikus merupakan salah satu mamalia yang dapat menjadi sumber penularan di daerah endemis schistosomiasis. Telah dilakukan penangkapan tikus dengan perangkap di 22 daerah fokus keong yang tersebar di 6 desa di Dataran Tinggi Napu, Kabupaten Poso, Sulawesi Tengah untuk mengetahui tingkat infeksi Schistosoma japonicum pada tikus. Hasilnya menunjukkan bahwa tingkat infeksi pada tikus sebesar 22,7% (5/22, dimana tingkat infeksi pada Rattus norvegicus lebih tinggi dibandingkan dengan Rattus exulans. Uji statistik dengan Fisher exact menunjukkan bahwa ada hubungan antara spesies tikus dengan infeksi cacing Schistosoma japonicum (P = 0, 039. Pengendalian tikus sangat sulit dilakukan sehingga diperlukan kerja sama lintas sektor antara Kementerian Kesehatan, Pertanian, Kehutanan dan Taman Nasional Lore Lindu. Kata kunci: Schistosoma japonicum, tikus, Dataran Tinggi Napu Abstract Rat is one of the mammals that can be the source of transmission in endemic areas schistosomiasis. Rat collection was done by using trap in 22 foci that spread in 6 villages in Napu Highland, Poso District Central Sulawesi. This study was done to investigate the infection rate of Schistosoma japonicum in rats. The result showed that infection rate of Schistosoma japonicum in rats was 22.7% (5/22. The infection rate in Rattus norvergicus was higher then in Rattus exulans. Fisher exact test showed that there is a relationship between species of rats and  schistosomiasis infection (P=0.039. To control rat’s population is difficult, therefore to control the disease inter sectoral cooperation Ministry of Health, Agriculture, Foresty, and Lore Lindu National Park is needed. Key words: Schistosoma japonicum, rat, Napu Highland

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

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    Santana Clara

    2009-10-01

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

  20. Ultrastructural Observation and Gene Expression Profiling of Schistosoma japonicum Derived from Two Natural Reservoir Hosts, Water Buffalo and Yellow Cattle

    OpenAIRE

    Jianmei Yang; Xingang Feng; Zhiqiang Fu; Chunxiu Yuan; Yang Hong; Yaojun Shi; Min Zhang; Jinming Liu; Hao Li; Ke Lu; Jiaojiao Lin

    2012-01-01

    Water buffalo and yellow cattle are the two of the most important natural reservoir hosts for Schistosoma japonicum in endemic areas of China, although their susceptibility differs, with water buffalo being less conducive to the growth and development of S. japonicum. Results from the current study show that the general morphology and ultrastructure of adult schistosomes derived from the two hosts also differed. Using high-throughput microarray technology, we also compared the gene expression...

  1. SjTPdb: integrated transcriptome and proteome database and analysis platform for Schistosoma japonicum

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    Wang Zhi-Qin

    2008-06-01

    Full Text Available Abstract Background Schistosoma japonicum is one of the three major blood fluke species, the etiological agents of schistosomiasis which remains a serious public health problem with an estimated 200 million people infected in 76 countries. In recent years, enormous amounts of both transcriptomic and proteomic data of schistosomes have become available, providing information on gene expression profiles for developmental stages and tissues of S. japonicum. Here, we establish a public searchable database, termed SjTPdb, with integrated transcriptomic and proteomic data of S. japonicum, to enable more efficient access and utility of these data and to facilitate the study of schistosome biology, physiology and evolution. Description All the available ESTs, EST clusters, and the proteomic dataset of S. japonicum are deposited in SjTPdb. The core of the database is the 8,420 S. japonicum proteins translated from the EST clusters, which are well annotated for sequence similarity, structural features, functional ontology, genomic variations and expression patterns across developmental stages and tissues including the tegument and eggshell of this flatworm. The data can be queried by simple text search, BLAST search, search based on developmental stage of the life cycle, and an integrated search for more specific information. A PHP-based web interface allows users to browse and query SjTPdb, and moreover to switch to external databases by the following embedded links. Conclusion SjTPdb is the first schistosome database with detailed annotations for schistosome proteins. It is also the first integrated database of both transcriptome and proteome of S. japonicum, providing a comprehensive data resource and research platform to facilitate functional genomics of schistosome. SjTPdb is available from URL: http://function.chgc.sh.cn/sj-proteome/index.htm.

  2. Genome-wide identification of Schistosoma japonicum microRNAs using a deep-sequencing approach.

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    Jian Huang

    Full Text Available BACKGROUND: Human schistosomiasis is one of the most prevalent and serious parasitic diseases worldwide. Schistosoma japonicum is one of important pathogens of this disease. MicroRNAs (miRNAs are a large group of non-coding RNAs that play important roles in regulating gene expression and protein translation in animals. Genome-wide identification of miRNAs in a given organism is a critical step to facilitating our understanding of genome organization, genome biology, evolution, and posttranscriptional regulation. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced two small RNA libraries prepared from different stages of the life cycle of S. japonicum, immature schistosomula and mature pairing adults, through a deep DNA sequencing approach, which yielded approximately 12 million high-quality short sequence reads containing a total of approximately 2 million non-redundant tags. Based on a bioinformatics pipeline, we identified 176 new S. japonicum miRNAs, of which some exhibited a differential pattern of expression between the two stages. Although 21 S. japonicum miRNAs are orthologs of known miRNAs within the metazoans, some nucleotides at many positions of Schistosoma miRNAs, such as miR-8, let-7, miR-10, miR-31, miR-92, miR-124, and miR-125, are indeed significantly distinct from other bilaterian orthologs. In addition, both miR-71 and some miR-2 family members in tandem are found to be clustered in a reversal direction model on two genomic loci, and two pairs of novel S. japonicum miRNAs were derived from sense and antisense DNA strands at the same genomic loci. CONCLUSIONS/SIGNIFICANCE: The collection of S. japonicum miRNAs could be used as a new platform to study the genomic structure, gene regulation and networks, evolutionary processes, development, and host-parasite interactions. Some S. japonicum miRNAs and their clusters could represent the ancestral forms of the conserved orthologues and a model for the genesis of novel miRNAs.

  3. Screening and identification of DNA aptamers toward Schistosoma japonicum eggs via SELEX

    Science.gov (United States)

    Long, Yuqian; Qin, Zhiqiang; Duan, Minlan; Li, Shizhu; Wu, Xiaoqiu; Lin, Wei; Li, Jianglin; Zhao, Zilong; Liu, Jing; Xiong, Dehui; Huang, Yi; Hu, Xiaoxiao; Yang, Chao; Ye, Mao; Tan, Weihong

    2016-01-01

    Schistosomiasis is a major parasitic disease caused by blood flukes of the genus Schistosoma. Several million people all over the world are estimated to suffer from severe morbidity as a consequence of schistosomiasis. The worm’s eggs, which cause the symptoms of schistosomiasis, are generally used to diagnose the disease. In this study, we employed egg-based systematic evolution of ligands by exponential enrichment (egg-SELEX) and identified a panel of ssDNA aptamers specifically binding to eggs derived from S. japonicum. Among these, two aptamers LC6 and LC15 exhibited strong binding to and specific recognition of S. japonicum eggs, but not eggs from Fasciolopsis buski, Enterobius, Ascaris or Clonorchis sinensis. Furthermore, tissue imaging results revealed that LC15 could recognize S. japonicum eggs laid in liver tissues with a detection ratio of 80.5%. Collectively, therefore, we obtained useful aptamers specifically recognizing S. japonicum eggs, which will facilitate the development of an effective tool for both schistosomiasis diagnosis and drug delivery. PMID:27121794

  4. Screening and identification of DNA aptamers toward Schistosoma japonicum eggs via SELEX.

    Science.gov (United States)

    Long, Yuqian; Qin, Zhiqiang; Duan, Minlan; Li, Shizhu; Wu, Xiaoqiu; Lin, Wei; Li, Jianglin; Zhao, Zilong; Liu, Jing; Xiong, Dehui; Huang, Yi; Hu, Xiaoxiao; Yang, Chao; Ye, Mao; Tan, Weihong

    2016-01-01

    Schistosomiasis is a major parasitic disease caused by blood flukes of the genus Schistosoma. Several million people all over the world are estimated to suffer from severe morbidity as a consequence of schistosomiasis. The worm's eggs, which cause the symptoms of schistosomiasis, are generally used to diagnose the disease. In this study, we employed egg-based systematic evolution of ligands by exponential enrichment (egg-SELEX) and identified a panel of ssDNA aptamers specifically binding to eggs derived from S. japonicum. Among these, two aptamers LC6 and LC15 exhibited strong binding to and specific recognition of S. japonicum eggs, but not eggs from Fasciolopsis buski, Enterobius, Ascaris or Clonorchis sinensis. Furthermore, tissue imaging results revealed that LC15 could recognize S. japonicum eggs laid in liver tissues with a detection ratio of 80.5%. Collectively, therefore, we obtained useful aptamers specifically recognizing S. japonicum eggs, which will facilitate the development of an effective tool for both schistosomiasis diagnosis and drug delivery. PMID:27121794

  5. Schistosoma japonicum: An ultraviolet-attenuated cercarial vaccine applicable in the field for water buffaloes

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Y.E.; Jiang, C.F.; Han, J.J.; Li, Y.L.; Ruppel, A. (Tongii Medical Univ., Wuhan, Hubei Province (China))

    1990-07-01

    Water buffaloes were vaccinated three times with 10,000 Schistosoma japonicum cercariae irradiated with ultraviolet (uv) light at a dose of 400 microW x min/cm2. The irradiation was performed with cheap, simple, and portable equipment in a rural area of Hubei Province (People's Republic of China). A challenge infection of 1000 untreated cercariae was given to six vaccinated and six naive control buffaloes, while two vaccinated animals were not challenged. The experiment was terminated 6 weeks after the challenge. Control animals had lost body weight and harbored a mean of 110 worms and 37 eggs per gram of liver. The vaccinated animals gained weight after the challenge and developed 89% resistance to infection with S. japonicum. Since schistosomiasis japonica is nowadays transmitted in China predominantly by domestic livestock, a uv-attenuated cercarial vaccine for bovines may contribute to the control of this disease.

  6. Schistosoma japonicum: An ultraviolet-attenuated cercarial vaccine applicable in the field for water buffaloes

    International Nuclear Information System (INIS)

    Water buffaloes were vaccinated three times with 10,000 Schistosoma japonicum cercariae irradiated with ultraviolet (uv) light at a dose of 400 microW x min/cm2. The irradiation was performed with cheap, simple, and portable equipment in a rural area of Hubei Province (People's Republic of China). A challenge infection of 1000 untreated cercariae was given to six vaccinated and six naive control buffaloes, while two vaccinated animals were not challenged. The experiment was terminated 6 weeks after the challenge. Control animals had lost body weight and harbored a mean of 110 worms and 37 eggs per gram of liver. The vaccinated animals gained weight after the challenge and developed 89% resistance to infection with S. japonicum. Since schistosomiasis japonica is nowadays transmitted in China predominantly by domestic livestock, a uv-attenuated cercarial vaccine for bovines may contribute to the control of this disease

  7. Induction of species-specific immunity against Schistosoma japonicum by exposure of rats to ultra-violet attenuated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Moloney, N.A.; Webbe, G.; Hinchcliffe, P.

    1987-02-01

    Single percutaneous immunizations of Fischer rats with 1000 ultra-violet attenuated Schistosoma japonicum cercariae induced 52-88% resistance to challenge 4 weeks later. Increasing this to 3 immunizations induced 90% resistance to challenge, and this level of protection remained undiminished for up to 40 weeks after vaccination. Rats vaccinated with gamma-irradiated S. mansoni cercariae were resistant to challenge with S. mansoni but not S. japonicum. Similarly rats vaccinated with u.v.-attenuated S. japonicum cercariae were not resistant to heterologous challenge. Thus irradiated vaccines are species-specific in both permissive and non-permissive hosts.

  8. The induction of species-specific immunity against Schistosoma japonicum by exposure of rats to ultra-violet attenuated cercariae

    International Nuclear Information System (INIS)

    Single percutaneous immunizations of Fischer rats with 1000 ultra-violet attenuated Schistosoma japonicum cercariae induced 52-88% resistance to challenge 4 weeks later. Increasing this to 3 immunizations induced 90% resistance to challenge, and this level of protection remained undiminished for up to 40 weeks after vaccination. Rats vaccinated with gamma-irradiated S. mansoni cercariae were resistant to challenge with S. mansoni but not S. japonicum. Similarly rats vaccinated with u.v.-attenuated S. japonicum cercariae were not resistant to heterologous challenge. Thus irradiated vaccines are species-specific in both permissive and non-permissive hosts. (author)

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

    Science.gov (United States)

    Yu, Yan-Rong; Ni, Xian-Qiang; Huang, Jie; Zhu, Yong-Hong; Qi, Yong-Fen

    2016-04-01

    In schistosomiasis, egg-induced hepatic granuloma formation is a cytokine-mediated, predominantly CD4(+) Th2 immune response that can give rise to hepatic fibrosis. Hepatic fibrosis is the main cause of increased morbidity and mortality in humans with schistosome infection. Taurine has various physiological functions and hepatoprotective properties as well as anti-inflammatory and immunomodulatory activity. However, little is known about the role of taurine in schistosome egg-induced granuloma formation and fibrosis. We aimed to evaluate the therapeutic potential of taurine as preventative treatment for Schistosoma japonicum infection. Mice infected with S. japonicum cercariae were supplied with taurine drinking water (1% w/v) for 4 weeks starting at 4 weeks post-infection. Taurine supplementation significantly improved the liver pathologic findings, reduced the serum levels of aminotransferases and area of hepatic granuloma, and prevented fibrosis progression. In addition, taurine decreased the expression of the granulomatous and fibrogenic mediators transforming growth factor β1, tumor necrosis factor α, monocyte chemotactic protein 1α and macrophage inflammatory protein 1α as well as the endoplasmic reticulum stress marker glucose-regulated protein 78. Thus, taurine can significantly attenuate S. japonicum egg-induced hepatic granuloma and fibrosis, which may depend in part on the downregulation of some relevant cytokine/chemokines and reducing the endoplasmic reticulum stress response. PMID:27054062

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

    Directory of Open Access Journals (Sweden)

    Yan-Rong Yu

    2016-04-01

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

  11. High prevalence of Schistosoma japonicum and Fasciola gigantica in bovines from Northern Samar, the Philippines.

    Directory of Open Access Journals (Sweden)

    Catherine A Gordon

    2015-02-01

    Full Text Available The cause of zoonotic schistosomiasis in the Philippines is Schistosoma japonicum, which infects up to 46 mammalian hosts, including humans and bovines. In China, water buffaloes have been identified as major reservoir hosts for schistosomiasis japonica, contributing up to 75% of human transmission. In the Philippines, water buffaloes (carabao; Bubalus bubalis carabanesis have, historically, been considered unimportant reservoirs. We therefore revisited the possible role of bovines in schistosome transmission in the Philippines, using the recently described formalin-ethyl acetate sedimentation (FEA-SD technique and a qPCR assay to examine fecal samples from 153 bovines (both carabao and cattle from six barangays in Northern Samar. A high prevalence of S. japonicum was found using qPCR and FEA-SD in both cattle (87.50% and 77.08%, respectively and carabao (80.00% and 55.24%, respectively. The average daily egg output for each bovine was calculated at 195,000. High prevalence and infection intensity of F. gigantica was also found in the bovines by qPCR and FEA-SD (95.33% and 96.00%, respectively. The identification of bovines as major reservoir hosts for S. japonicum transmission suggests that bovine treatment and/or vaccination, as one becomes available, should be included in any future control program that aims to reduce the disease burden due to schistosomiasis in the Philippines.

  12. Effect of ozonide OZ418 against Schistosoma japonicum harbored in mice.

    Science.gov (United States)

    Xue, Jian; Wang, Xiaofang; Dong, Yuxiang; Vennerstrom, Jonathan L; Xiao, Shu-hua

    2014-09-01

    The in vitro and in vivo efficacies of ozonide carboxylic acid OZ418 against Schistosoma japonicum were investigated. For in vitro experiments, juvenile (14-day-old) and adult schistosomes were collected from mice infected with 80-100 S. japonicum cercariae for 14 and 35 days post-infection and the worms were maintained in Roswell Park Memorial Institute (RPMI) 1640 supplemented by 10% calf serum. Against 35-day-old adult S. japonicum, OZ418 resulted in weakened worm motor activity, injury to the worm body, emergence of vacuoles along the worm surface, and death. A similar outcome was seen in 14-day-old juvenile S. japonicum exposed to OZ418. Ineffective concentrations (1, 5, and 10 μg/mL) of OZ418 also interacted with hemin to significantly increase the killing effect against adult schistosomes. The LC50 value of OZ418 against juvenile (14-day-old) and adult schistosomes were identical--16.2 μg/mL, whereas the corresponding LC95 values were 30.7 and 22.7 μg/mL, respectively. Treatment of adult and juvenile (14-day-old) S. japonicum-infected mice with single 200-400-mg/kg oral doses of OZ418 produced total worm burden reductions of 68.5-84.1 and 37.5-50.9%, respectively. Further study showed that in mice infected with various stages of schistosomes and treated with a single oral OZ418 400 mg/kg, poor efficacy was seen in the 3-h-old juvenile worm group, while 14-day-old and 21-day-old juvenile worm groups exhibited less efficacy with total worm burden reductions of 42.6-52.4%. On the other hand, similar and higher total worm burden reductions (64.2-76.0%) were seen in the 7-day-old juvenile worm group and 28-day-old as well as 35-day-old adult worm groups. Furthermore, the mean worm burden reductions of the 7-day-old juvenile worm group and 35-day-old adult worm group were statistically significantly higher than that of the 14-day-old or 21-day-old juvenile worm group (P < 0.01 or <0.05). These data suggest that OZ418 has promising efficacy against 7-day

  13. Immunization of pigs against infection with Schistosoma japonicum using ultraviolet-attenuated cercariae

    International Nuclear Information System (INIS)

    Since pigs are important in the zoonotic transmission of schistosomiasis japonica in China, a veterinary vaccine might contribute to the control of the disease in humans. Pigs were immunized with three doses each of 10 000 cercariae of Schistosoma japonicum attenuated with ultraviolet light (400 μWatt.min/cm2). The experiment was performed with portable irradiation equipment in a rural area of the Hubei Province (P.R. China). A challenge infection of 1000 untreated cercariae was given 2.5 or 6 months after the last immunization, and age-matched naive pigs were challenged as a control. Immunized pigs developed about 90% resistance against the challenge. The liver egg load of these animals was reduced by over 90%. Less than 0.01% of the immunizing cercariae developed to adult parasites and the vaccination had no apparent adverse influence on the pig's health. (Author)

  14. Immunization of pigs against infection with Schistosoma japonicum using ultraviolet-attenuated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Y.-E.; Jiang, C.-F.; Han, J.-J.; Li, Y.-L. (Tongji Medical Univ., Wuhan (China). Dept. of Parasitology); Ruppel, A. (Institute for Tropical Hygiene, Heidelberg (Germany))

    1993-06-01

    Since pigs are important in the zoonotic transmission of schistosomiasis japonica in China, a veterinary vaccine might contribute to the control of the disease in humans. Pigs were immunized with three doses each of 10 000 cercariae of Schistosoma japonicum attenuated with ultraviolet light (400 [mu]Watt.min/cm[sup 2]). The experiment was performed with portable irradiation equipment in a rural area of the Hubei Province (P.R. China). A challenge infection of 1000 untreated cercariae was given 2.5 or 6 months after the last immunization, and age-matched naive pigs were challenged as a control. Immunized pigs developed about 90% resistance against the challenge. The liver egg load of these animals was reduced by over 90%. Less than 0.01% of the immunizing cercariae developed to adult parasites and the vaccination had no apparent adverse influence on the pig's health. (Author).

  15. Screening and Primary Characterization of New Antigen Genes of Schistosoma Japonicum

    Institute of Scientific and Technical Information of China (English)

    王敏; 易新元; 李先平; 曾宪芳; 章洁

    2004-01-01

    To find Schistosoma japonicum(S.j) new antigen gene thus provide more useful vaccine candidates, the cDNA library of S. j adult worm was screened with sera of rabbits immtmized with the membrane antigens of Schistosoma japonicum hepato-portal schistosomula (SjHmAg). The positive clones were amplified by PCR and sequenced, then the sequences of clones were compared with all sequences in GenBank database using Blast process. The new clones were submitted to GenBank for accession numbers. Fifteen positive clones were obtained after three rounds of i mmunoscreening. The size of S. j cDNA fragments in positive clones ranged from 0.7 kb-3.0 kb after automatically excised with the helper phage. Sequence analysis revealed that partial sequence of clone M5 had significant homology with S.j mitochondria rnRNA, the other positive clones were new S.j genes. M2 clone sequence (GenBank accession number AF502579) was 730 bp long it had a 117 bp open reading frame (ORF). The sequence of M15 (GenBank accession number AF502582) has no transmembrane region and encodes 92 amino acids, and its protein contains a ferredoxins iron-sulfur binding region signature and two VWFC signal regions. The size of M1 ,M8, M9, M12( GenBank accession numbers: AF502578, AF502580, AF500622, AF502581 ) ranges from 402 bp to 766 bp. It concluded that the sera from rabbit immunized with SjHmAg could recognize S. j specific antigens molecules, and these antigens may induce the protective immunity against S.j infection.

  16. Spatial distribution of human Schistosoma japonicum infections in the Dongting Lake Region, China.

    Directory of Open Access Journals (Sweden)

    Giovanna Raso

    Full Text Available BACKGROUND: The aim of this study was to spatially model the effect of demographic, reservoir hosts and environmental factors on human Schistosoma japonicum infection prevalence in the Dongting Lake area of Hunan Province, China and to determine the potential of each indicator in targeting schistosomiasis control. METHODOLOGY/PRINCIPAL FINDINGS: Cross-sectional serological, coprological and demographic data were obtained from the 2004 nationwide periodic epidemiologic survey for Hunan Province. Environmental data were downloaded from the USGS EROS data centre. Bayesian geostatistical models were employed for spatial analysis of the infection prevalence among study participants. A total of 47,139 participants from 47 administrative villages were selected. Age, sex and occupation of residents and the presence of infected buffaloes and environmental factors, i.e. NDVI, distance to the lake and endemic type of setting, were significantly associated with S. japonicum infection prevalence. After taking into account spatial correlation, however, only demographic factors (age, sex and occupation and the presence of infected buffaloes remained significant indicators. CONCLUSIONS/SIGNIFICANCE: Long established demographic factors, as well presence of host reservoirs rather than environmental factors are driving human transmission. Findings of this work can be used for epidemiologic surveillance and for the future planning of interventions in the Dongting Lake area of Hunan Province.

  17. The induction of specific immunity against Schistosoma japonicum by exposure of mice to ultraviolet attenuated cercariae

    International Nuclear Information System (INIS)

    Mice can be partially protected against Schistosoma japonicum by prior exposure to ultraviolet (UV)-attenuated infections which fail to survive to the adult stage and produce no overt pathology in the host. Optimum resistance was induced by parasites exposed to 40 seconds of UV, significantly lower levels of resistance being stimulated by both shorter and longer exposures. No consistent relationship between the degree of resistance induced and the number of irradiated cercariae given could be demonstrated and equivocal results were obtained when comparing the efficacy of single and multiple vaccinations. Vaccinations with UV-attenuated cercariae given intraperitoneally (i.p.) were as efficacious as those given percutaneously but mice were as or more resistant to challenges given by the i.p. route, the possible reasons are discussed. There was no observed delay in the migration of the challenge, vaccinated mice being as resistant when perfused 6 or 3.5 weeks after challenge. Vaccination was species specific since mice exposed to either UV-attenuated S. japonicum cercariae or gamma-attenuated S. mansoni cercariae were resistant to homologous but not heterologous challenge. (author)

  18. Induction of specific immunity against Schistosoma japonicum by exposure of mice to ultraviolet attenuated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Moloney, N.A.; Bickle, Q.D.; Webbe, G. (London School of Hygiene and Tropical Medicine, St. Albans (UK). Winches Farm Field Station)

    1985-01-01

    Mice can be partially protected against Schistosoma japonicum by prior exposure to ultraviolet (UV)-attenuated infections which fail to survive to the adult stage and produce no overt pathology in the host. Optimum resistance was induced by parasites exposed to 40 seconds of UV, significantly lower levels of resistance being stimulated by both shorter and longer exposures. No consistent relationship between the degree of resistance induced and the number of irradiated cercariae given could be demonstrated and equivocal results were obtained when comparing the efficacy of single and multiple vaccinations. Vaccinations with UV-attenuated cercariae given intraperitoneally (i.p.) were as efficacious as those given percutaneously but mice were as or more resistant to challenges given by the i.p. route, the possible reasons are discussed. There was no observed delay in the migration of the challenge, vaccinated mice being as resistant when perfused 6 or 3.5 weeks after challenge. Vaccination was species specific since mice exposed to either UV-attenuated S. japonicum cercariae or gamma-attenuated S. mansoni cercariae were resistant to homologous but not heterologous challenge.

  19. The temperature--dependent expression of GST of Schistosoma japonicum (Philippine strain).

    Science.gov (United States)

    Cai, Z H; Song, G C; Xu, Y X; Liu, S X

    1993-03-01

    Obtained from pSj5, the cDNA gene encoding GST antigen of Schistosoma japonicum (Philippine strain) was ligated with efficient temperature-dependent PBV220 vector which was constructed in CAPM, and then introduced into host bacterium-DH5 alpha (E. coli) by transformation. Transformants were selected by ampicillin and recombinant clones were identified by restriction mapping. The result showed that recombinant clone 43 was the one carrying recombinant plasmid PBV 220 with the correct insertion of the gene fragment. The GST expression ability of clone 43 was investigated by GST enzymic activity assay and SDS-PAGE. A relatively high level of GST enzymic activity was expressed by this clone under the temperature-dependent condition, that is, cultured at 30 degrees C and expressed at 42 degrees C. A more strongly stained 26 kDa protein band was identified by SDS-PAGE. The result indicated that GST of S. japonicum (Philippine strain) could be expressed not only by IPTG induction, but also by the temperature-dependent method. PMID:8362308

  20. A strategy for emergency treatment of Schistosoma japonicum-infested water

    Directory of Open Access Journals (Sweden)

    Li Hong-Jun

    2011-11-01

    Full Text Available Abstract Background Schistosomiasis japonica, caused by contact with Schistosoma japonicum cercaria-infested water when washing, bathing or production, remains a major public-health concern in China. The purpose of the present study was to investigate the effect of a suspension concentrate of niclosamide (SCN on killing cercaria of S. japonicum that float on the water surface, and its toxicity to fish, so as to establish an emergency-treatment intervention for rapidly killing cercaria and eliminating water infectivity. Results At 30 min after spraying 100 mg/L SCN, with niclosamide dosages of 0.01, 0.02, 0.03, 0.04 g/m2, the water infectivity reduced significantly and no infectivity was found at 60 min after spraying SCN. The surface of static water was sprayed with 100 mg/L SCN, the peak concentration was found at 0 min, and the solution diffused to site with a water depth of 10 cm after 10 min. 30 min later, SCN diffused to the whole water body, and distributed evenly. After spraying 100 mg/L SCN onto the surface of the water with a volume of(3.14 × 202×50cm3, with niclosamide dosages of 0.02 g/m2, 96 h later, no death of zebra fish was observed. Conclusions By spraying 100 mg/L SCN, with a niclosamide dosage of 0.02 g/m2 onto the surface of S. japonicum-infested water, infectivity of the water can be eliminated after 30-60 min, and there is no evident toxicity to fish. This cercaria-killing method, as an emergency-treatment intervention for infested water, can be applied in those forecasting and early warning systems for schistosomiasis.

  1. Screening diagnostic candidates for schistosomiasis from tegument proteins of adult Schistosoma japonicum using an immunoproteomic approach.

    Directory of Open Access Journals (Sweden)

    Min Zhang

    2015-02-01

    Full Text Available Schistosomiasis is one of the world's most prevalent zoonotic diseases and a serious worldwide public health problem. Since the tegument (TG of Schistosoma japonicum is in direct contact with the host and induces a host immune response against infection, the identification of immune response target molecules in the schistosome TG is crucial for screening diagnostic antigens for this disease.In this study, an immunoproteomics approach used TG proteins as screening antigens to identify potential diagnostic molecules of S. japonicum. Ten spots corresponding to six proteins were identified that immunoreacted with sera from S. japonicum-infected rabbits but not sera from uninfected rabbits and their specific IgG antibody levels declined quickly after praziquantel treatment. Recombinant phosphoglycerate mutase (PGM and UV excision repair protein RAD23 homolog B (RAD23 proteins were expressed and their diagnostic potential for schistosomiasis was evaluated and compared with schistosome soluble egg antigen (SEA using ELISA. The results showed high sensitivity and specificity and low crossreactivity when rSjPGM-ELISA and rSjRAD23-ELISA were used to detect water buffalo schistosomiasis. Moreover, antibodies to rSjPGM and rSjRAD23 might be short-lived since they declined quickly after chemotherapy.Therefore, the two schistosome TG proteins SjPGM and SjRAD23 were identified as potential diagnostic markers for the disease. The two recombinant proteins might have the potential to evaluate the effectiveness of drug treatments and for distinguishing between current and past infection.

  2. Origin of a novel protein-coding gene family with similar signal sequence in Schistosoma japonicum

    Directory of Open Access Journals (Sweden)

    Mbanefo Evaristus

    2012-06-01

    Full Text Available Abstract Background Evolution of novel protein-coding genes is the bedrock of adaptive evolution. Recently, we identified six protein-coding genes with similar signal sequence from Schistosoma japonicum egg stage mRNA using signal sequence trap (SST. To find the mechanism underlying the origination of these genes with similar core promoter regions and signal sequence, we adopted an integrated approach utilizing whole genome, transcriptome and proteome database BLAST queries, other bioinformatics tools, and molecular analyses. Results Our data, in combination with database analyses showed evidences of expression of these genes both at the mRNA and protein levels exclusively in all developmental stages of S. japonicum. The signal sequence motif was identified in 27 distinct S. japonicum UniGene entries with multiple mRNA transcripts, and in 34 genome contigs distributed within 18 scaffolds with evidence of genome-wide dispersion. No homolog of these genes or similar domain was found in deposited data from any other organism. We observed preponderance of flanking repetitive elements (REs, albeit partial copies, especially of the RTE-like and Perere class at either side of the duplication source locus. The role of REs as major mediators of DNA-level recombination leading to dispersive duplication is discussed with evidence from our analyses. We also identified a stepwise pathway towards functional selection in evolving genes by alternative splicing. Equally, the possible transcription models of some protein-coding representatives of the duplicons are presented with evidence of expression in vitro. Conclusion Our findings contribute to the accumulating evidence of the role of REs in the generation of evolutionary novelties in organisms’ genomes.

  3. Spatial risk profiling of Schistosoma japonicum in Eryuan county, Yunnan province, China

    Directory of Open Access Journals (Sweden)

    Peter Steinmann

    2007-11-01

    Full Text Available Bayesian spatial risk profiling holds promise to enhance our understanding of the epidemiology of parasitic diseases, and to target interventions in a cost-effective manner. Here, we present findings from a study using Bayesian variogram models to map and predict the seroprevalence of Schistosoma japonicum in Eryuan county, Yunnan province, China, including risk factor analysis. Questionnaire and serological data were obtained through a cross-sectional survey carried out in 35 randomly selected villages with 3,220 people enrolled. Remotely-sensed environmental data were derived from publicly available databases. Bivariate and non-spatial Bayesian multiple logistic regression models were used to identify associations between the local seroprevalence and demographic (i.e. age and sex, environmental (i.e. location of village, altitude, slope, land surface temperature and normalized difference vegetation index and socio-economic factors. In the spatially-explicit Bayesian model, S. japonicum seroprevalence was significantly associated with sex, age and the location of the village. Males, those aged below 10 years and inhabitants of villages situated on steep slopes (inclination ≥20° or on less precipitous slopes of >5° above 2,150 m were at lower risk of seroconversion than their respective counterparts. Our final prediction model revealed an elevated risk for seroconversion in the plains of the eastern parts of Eryuan county. In conclusion, the prediction map can be utilized for spatial targeting of schistosomiasis control interventions in Eryuan county. Moreover, S. japonicum seroprevalence studies might offer a convenient means to assess the infection pressure experienced by local communities, and to improve risk profiling in areas where the prevalence and infection intensities have come down following repeated rounds of praziquantel administration.

  4. ANALISIS GEN PENYANDI Schistosoma japonicum Gluthation s Transferase (SJ26GST) DI DATARAN TINGGI LINDU, SULAWESI TENGAH INDONESIA

    OpenAIRE

    Anis Nurwidayati; Triwibowo A. Garjito; Phetisya Pamela Frederika Sumolang; Risti Risti

    2015-01-01

    AbstractSchistosomiasis is only found at Napu and Lindu highland, Central Sulawesi in Indonesia. Schistosomiasis still as a public health problem, with its prevalence increase every year. The large scale by mass drug treatment using praziquantel has done to reduce the prevalence since 1980. To look for the possibility evidence of the development of resistance in S. japonicumto praziquantel in endemic areas by analysis of Schistosoma japonicumGluthation S Transferase (Sj26gst) Coding Gene. Mol...

  5. Immune Events Associated with High Level Protection against Schistosoma japonicum Infection in Pigs Immunized with UV-Attenuated Cercariae

    OpenAIRE

    Tian, Fang; Lin, Dandan; Wu, Jingjiao; Gao, Yanan; Zhang, Donghui; Ji, Minjun; Wu, Guanling

    2010-01-01

    Background The vaccination of radiation-attenuated Schistosoma japonicum cercariae can induce effective protection in artiodactyl, but the immune events related to protective immunity are not fully understood. To provide a paradigm for a human recombinant antigen vaccine, we have undertaken a vaccination and challenge experiment in pigs, which was recognized as an appropriate animal model in this type of study because of their similarity to human in immunology, and investigated the relative i...

  6. Global Expression Analysis Revealed Novel Gender-Specific Gene Expression Features in the Blood Fluke Parasite Schistosoma japonicum

    OpenAIRE

    Xianyu Piao; Pengfei Cai; Shuai Liu; Nan Hou; Lili Hao; Fan Yang; Heng Wang; Jianwei Wang; Qi Jin; Qijun Chen

    2011-01-01

    BACKGROUND: Schistosoma japonicum is one of the remarkable Platyhelminths that are endemic in China and Southeast Asian countries. The parasite is dioecious and can reside inside the host for many years. Rapid reproduction by producing large number of eggs and count-react host anti-parasite responses are the strategies that benefit long term survival of the parasite. Praziquantel is currently the only drug that is effective against the worms. Development of novel antiparasite reagents and imm...

  7. The effect of colostrum on pigs pre-natally or post-natally exposed to Schistosoma japonicum

    DEFF Research Database (Denmark)

    Techau, M.E.; Johansen, M.V.; Lind, Peter; Ornbjerg, N.

    2004-01-01

    Pre-natal infection of Schistosoma japonicum in pigs may prove to be a useful model in shedding light on human pre-natal schistosomiasis. This study describes the effects of immune colostrum on worm burdens, tissue egg counts, liver pathology and crude worm or egg antigen-specific IgG and Ig......A responses, in groups of pigs pre-natally, pre-natally + post-natally or post-natally exposed to S. japonicum. Results suggest that pre-natal exposure and immune colostrum did not affect the establishment of a post-natal challenge infection. However, immune colostrum seemed to increase the levels of septal...... fibrosis in pre-natally exposed pigs. These findings indicate that further investigations will prove valuable, elucidating the influence of the parasitological and immunological status of the sow, on pre-natally exposed pigs, and on the ability of these pigs to develop resistance against S. japonicum later...

  8. The effect of colostrum on pigs pre-natally or post-natally exposed to Schistosoma japonicum

    DEFF Research Database (Denmark)

    Techau, M.E.; Johansen, M.V.; Lind, Peter;

    2004-01-01

    fibrosis in pre-natally exposed pigs. These findings indicate that further investigations will prove valuable, elucidating the influence of the parasitological and immunological status of the sow, on pre-natally exposed pigs, and on the ability of these pigs to develop resistance against S. japonicum later......Pre-natal infection of Schistosoma japonicum in pigs may prove to be a useful model in shedding light on human pre-natal schistosomiasis. This study describes the effects of immune colostrum on worm burdens, tissue egg counts, liver pathology and crude worm or egg antigen-specific IgG and Ig......A responses, in groups of pigs pre-natally, pre-natally + post-natally or post-natally exposed to S. japonicum. Results suggest that pre-natal exposure and immune colostrum did not affect the establishment of a post-natal challenge infection. However, immune colostrum seemed to increase the levels of septal...

  9. The inhibitory effect against collagen-induced arthritis by Schistosoma japonicum infection is infection stage-dependent

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    Chi FengLi

    2010-06-01

    Full Text Available Abstract Background A long-term existing schistosome infection can aid in maintaining immuno-homeostasis, thus providing protection against various types of autoimmune diseases to the infected host. Such benefits have often been associated with acute or egg stage infection and with the egg-induced Th2 response. However, since schistosome infection undergoes different stages, each associated with a specific induction of Th responses, the requirements for the ability of the different stages of schistosome infection to protect against autoimmune disease has not been elucidated. The present study was designed to study whether different stages of schistosome infection offer unique protection in collagen-induced arthritis and its mechanisms. Results Arthritis susceptible strain DBA/1 male mice were infected with Schistosoma japonicum for either 2 weeks resulting in early stage infection or for 7 weeks resulting in acute or egg stage infection. Following Schistosoma japonicum infection, collagen II was administered to induce collagen-induced arthritis, an animal model for human rheumatoid arthritis. Infection by Schistosoma japonicum significantly reduced the severity and the incidence of experimental autoimmune collagen-induced arthritis. However, this beneficial effect can only be provided by a pre-established acute stage of infection but not by a pre-established early stage of the infection. The protection against collagen-induced arthritis correlated with reduced levels of anti-collagen II IgG, especially the subclass of IgG2a. Moreover, in protected mice increased levels of IL-4 were present at the time of collagen II injection together with sustained higher IL-4 levels during the course of arthritis development. In contrast, in unprotected mice minimal levels of IL-4 were present at the initial stage of collagen II challenge together with lack of IL-4 induction following Schistosoma japonicum infection. Conclusion The protective effect against

  10. 东方田鼠抗日本血吸虫病机制研究%Study on the Mechanism of Microtus fortis Against Schistosoma Japonicum

    Institute of Scientific and Technical Information of China (English)

    刘金明; 刘瑞三; 林矫矫; 傅志强; 李浩; 魏梅雄; 孙军; 张亮; 何艳燕; 蒋守富

    2003-01-01

    This paper was about the study on the mechanism of Microtus fortis against Schistosoma japonicum. Firstly,we confirmed that Microtus fortis came from epidemic region (Dongting Lake beaches) and non-epidemic region (Qingtong Gorge in Ningxia province) were both resistant to Schistosoma japonicum infection after re-infection tests for several times. It seemed that their resistant ability was inheritable rather than acquired. Secondly, it was demonstrated by in vivo check-up and in vitro killing assay that there were some native antibodies of IgG3 subclass specifically to the schistosomula and adult worm of Schistosoma japonicum in Microtus fortis, which probably played an important role in resisting Schistosoma japonicum associated with complement. It was shown that macrophages and eosinophils in abdominal cavity of Microtus fortis had native ability of adhering to the schistosomula of Schistosoma japonicum. Then, the adult worm cDNA library of Schistosoma japonicum was screened with sera from Microtus fortis. Five positive clones were obtained, four of which were identified as new genes. Full-length cDNA of the two new genes were isolated by RACE. DNA vaccine was constructed with one named EST-mfs-3. After the Kunming mice immunized with this vaccine, the worm reduction rate and the egg reduction rate were 28.4% and 21.73% compared with that in control group respectively. This kind of DNA-based EST-mfs-3 vaccine was highly expressed in E. coli and induecd strong immune response in challenged group.Finally, two groups of cDNA probes prepared from liver and lung of Microtusfortis with or without Schistosoma japonicum infection were hybridized to the eDNA chip prepared from rat respectively. 156 and 332 genes revealed differential expression in infectious group compared with normal group. In conclusion, there would be many factors contribute to the mechanism of Microtusfortis against Schistosoma japonicum. We should stress the essentials and make further research on

  11. Intake of Erythrocytes Required for Reproductive Development of Female Schistosoma japonicum.

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    Jipeng Wang

    Full Text Available The reproductive development and maturation of female schistosomes are crucial since their released eggs are responsible for the host immunopathology and transmission of schistosomiasis. However, little is known about the nutrients required by female Schistosoma japonicum during its sexual maturation. We evaluated the promoting effect of several nutrients (calf serum, red blood cells (RBCs, ATP and hypoxanthine on the reproductive development of pre-adult females at 18 days post infection (dpi from mixed infections and at 50 dpi from unisexual infections of laboratory mice in basic medium RPMI-1640. We found RBCs, rather than other nutrients, promoted the female sexual maturation and egg production with significant morphological changes. In 27% of females (18 dpi from mixed infections that paired with males in vitro on day 14, vitelline glands could be positively stained by Fast Blue B; and in 35% of females (50 dpi from unisexual infections on day 21, mature vitelline cells were observed. Infertile eggs were detected among both groups. To analyze which component of mouse RBCs possesses the stimulating effect, RBCs were fractionated and included in media. However, the RBC fractions failed to stimulate development of the female reproductive organs. In addition, bovine hemoglobin hydrolysate, digested by neutral protease, was found to exhibit the promoting activity instead of untreated bovine hemoglobin. The other protein hydrolysate, lactalbumin hydrolysate, exhibited a similar effect with bovine hemoglobin hydrolysate. Using quantitative RT-PCR, we found the expression levels of four reproduction-related genes were significantly stimulated by RBCs. These data indicate that RBCs provide essential nutrients for the sexual maturation of female S. japonicum and that the protein component of RBCs appeared to constitute the key nutrient. These findings would improve laboratory culture of pre-adult schistosomes to adult worms in medium with well

  12. Identification and characterization of microRNAs and endogenous siRNAs in Schistosoma japonicum

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    Wang Heng

    2010-01-01

    Full Text Available Abstract Background Small endogenous non-coding RNAs (sncRNAs such as small interfering RNA (siRNA, microRNA and other small RNA transcripts are derived from distinct loci in the genome and play critical roles in RNA-mediated gene silencing mechanisms in plants and metazoa. They are approximately 22 nucleotides long; regulate mRNA stability through perfect or imperfect match to the targets. The biological activities of sncRNAs have been related to many biological events, from resistance to microbe infections to cellular differentiation. The development of the zoonotic parasite Schistosoma japonicum parasite includes multiple steps of morphological alterations and biological differentiations, which provide a unique model for studies on the functions of small RNAs. Characterization of the genome-wide transcription of the sncRNAs will be a major step in understanding of the parasite biology. The objective of this study is to investigate the transcriptional profile and potential function of the small non-coding RNAs in the development of S. japanicum. Results The endogenous siRNAs were found mainly derived from transposable elements (TE or transposons and the natural antisense transcripts (NAT. In contrast to other organisms, the TE-derived siRNAs in S. japonicum were more predominant than other sncRNAs including microRNAs (miRNAs. Further, there were distinct length and 3'end variations in the sncRNAs, which were associated with the developmental differentiation of the parasite. Among the identified miRNA transcripts, there were 38 unique to S. japonicum and 16 that belonged to 13 miRNA families are common to other metazoan lineages. These miRNAs were either ubiquitously expressed, or they exhibited specific expression patterns related to the developmental stages or sex. Genes that encoded miRNAs are mainly located in clusters within the genome of S. japonicum. However, genes within one cluster could be differentially transcribed, which suggested

  13. A Microtus fortis protein, serum albumin, is a novel inhibitor of Schistosoma japonicum schistosomula

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    Rong Li

    2013-11-01

    Full Text Available Schistosomiasis is an endemic parasite disease and praziquantel is the only drug currently in use to control this disease. Experimental and epidemiological evidence strongly suggests that Microtus fortis ( Mf is a naturally resistant vertebrate host of Schistosoma japonicum . In the present study, we found that Mf serum albumin ( Mf -albumin and the conditioned medium of pcDNA3.1- Mf -albumin caused 46.2% and 38.7% schistosomula death rates in 96 h, respectively, which were significantly higher than that of the negative control (p < 0.05. We also found that mice injected with Mf -albumin had a 43.5% reduction in worm burden and a 48.1% reduction in liver eggs per gram (p < 0.05 in comparison to the control animals. To characterise the mechanisms involved in clearance, schistosomula were incubated with fluorescein isothiocyanate-labelled Mf -albumin and fluorescent enrichment effects were found in the gut lumen of schistosomula after 48 h of incubation. Next, digestive tract excretions from schistosomula were collected and the sensitivity of Mf -albumin to digestive tract excretions was evaluated. The results indicated that schistosomula digestive tract excretions showed indigestibility of Mf -albumin. The death of schistosomula could be partially attributed to the lack of digestion of Mf -albumin by digestive tract excretions during the development of the schistosomula stage. Therefore, these data indicate the potential of Mf -albumin as one of the major selective forces for schistosomiasis.

  14. Chronic Schistosoma japonicum infection reduces immune response to vaccine against hepatitis B in mice.

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    Lin Chen

    Full Text Available BACKGROUND: Hepatitis B and schistosomiasis are most prevalent in Africa and Asia, and co-infections of both are frequent in these areas. The immunomodulation reported to be induced by schistosome infections might restrict immune control of hepatitis B virus (HBV leading to more severe viral infection. Vaccination is the most effective measure to control and prevent HBV infection, but there is evidence for a reduced immune response to the vaccine in patients with chronic schistosomiasis japonica. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate in a mouse model that a chronic Schistosoma japonicum infection can inhibit the immune response to hepatitis B vaccine (HBV vaccine and lead to lower production of anti-HBs antibodies, interferon-γ (IFN-γ and interleukin-2 (IL-2. After deworming with Praziquantel (PZQ, the level of anti-HBs antibodies gradually increased and the Th2-biased profile slowly tapered. At 16 weeks after deworming, the levels of anti-HBs antibodies and Th1/Th2 cytokines returned to the normal levels. CONCLUSIONS/SIGNIFICANCE: The results suggest that the preexisting Th2-dominated immune profile in the host infected with the parasite may down-regulate levels of anti-HBs antibodies and Th1 cytokines. To improve the efficacy of HBV vaccination in schistosome infected humans it may be valuable to treat them with praziquantel (PZQ some time prior to HBV vaccination.

  15. Helminth Protein Vaccine Induced Follicular T Helper Cell for Enhancement of Humoral Immunity against Schistosoma japonicum

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    Jingyao Zhang

    2013-01-01

    Full Text Available Protein vaccines combined with adjuvants have been widely used to induce immune responses, especially the humoral immune response, against molecular targets including parasites. Follicular T helper (Tfh cells are the specialized providers of B-cell help, however, the induction of Tfh cells in protein vaccination has been rarely studied. Here, we report that the Schistosoma japonicum recombinant protein (SjGST-32 combined with tacrolimus (FK506 augmented the induction of Tfh cells, which expressed the canonical markers CXCR5, BCL6, and IL-21, and enhanced the humoral immune responses in BALB/c mice. Furthermore, the expression of IL-21R on germinal center (GC B cells and memory B cells increased in immunized mice, which indicated that IL-21 from the induced Tfh cells interacted with IL-21R for activation of B cells and maintenance of long-lived humoral immunity. Our results suggest that helminth protein vaccine combined with FK506 induces Tfh cell for stimulating humoral immune responses and inducing long-lived humoral immunity.

  16. The Differential Expression of Immune Genes between Water Buffalo and Yellow Cattle Determines Species-Specific Susceptibility to Schistosoma japonicum Infection

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    Jianmei Yang; Zhiqiang Fu; Yang Hong; Haiwei Wu; Yamei Jin; Chuangang Zhu; Hao Li; Ke Lu; Yaojun Shi; Chunxiu Yuan; Guofeng Cheng; Xingang Feng; Jinming Liu; Jiaojiao Lin

    2015-01-01

    Water buffalo are less susceptible to Schistosoma japonicum infection than yellow cattle. The factors that affect such differences in susceptibility remain unknown. A Bos taurus genome-wide gene chip was used to analyze gene expression profiles in the peripheral blood of water buffalo and yellow cattle pre- and post-infection with S. japonicum. This study showed that most of the identified differentially expressed genes (DEGs) between water buffalo and yellow cattle pre- and post-infection we...

  17. Construction of a recombinant plasmid pGEX-Sj26GST of Schistosoma japonicum and expression in Escherichia coli BL21( DE3)

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    张丽

    2014-01-01

    Objective To construct and express a recombinant plasmid pGEX-Sj26GST of Schistosoma japonicum(Sj)in Escherichia coli(E.coli)BL21(DE3).Methods Total RNA was extracted from Sj adult worms by RNeasy Mini kit,26 kilodalton glutathione-S-transferases of Schistosoma japonicum(Sj26GST)antigen gene was amplified by real-time PCR(RT-PCR)from the total RNA,then cloned into a prokaryotic expression plasmid pGEX-1λT and transformed into E.coli BL21(DE3)to construct pGEX-Sj26GST;BL21(pGEX-

  18. The Sensitivity of Schistosoma japonicum to Praziquantel: A Field Evaluation in Areas with Low Endemicity of China

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    Wang, Wei; Dai, Jian-Rong; LI, HONG-JUN; Shen, Xue-Hui; Liang, You-Sheng

    2012-01-01

    The purpose of the current study was to investigate the susceptibility of Schistosoma japonicum to praziquantel in low endemic foci of China. During the non-transmission period of schistosomiasis, a total of 43 of 1,242 subjects were identified as being infected with the parasite using parasitological stool examinations in two low-endemicity areas of China, with a prevalence rate of 3.46%. All stool-egg-positive subjects were treated with praziquantel in a single oral dose of 40 mg/kg or 30 m...

  19. ANALISIS GEN PENYANDI Schistosoma japonicum Gluthation s Transferase (SJ26GST DI DATARAN TINGGI LINDU, SULAWESI TENGAH INDONESIA

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    Anis Nurwidayati

    2015-01-01

    Full Text Available AbstractSchistosomiasis is only found at Napu and Lindu highland, Central Sulawesi in Indonesia. Schistosomiasis still as a public health problem, with its prevalence increase every year. The large scale by mass drug treatment using praziquantel has done to reduce the prevalence since 1980. To look for the possibility evidence of the development of resistance in S. japonicumto praziquantel in endemic areas by analysis of Schistosoma japonicumGluthation S Transferase (Sj26gst Coding Gene. Moleculer laboratory study was conducted to analyse the sequences of S. japonicumgluthation s transferase gene (Sj26GST. DNA was extracted from adult S. japonicumusing isopropanol. Sj26GST gene was amplified used gradient PCR. The PCR result then run with electrophoresis and viewed using gel-doc. The Sj26GST band was cut and purified using Gene Aid Purification kitand amplified by PCR cycle sequencing, and the product was sequenced using Abi PRISM 310 Genetic analyser. The gene sequences of Sj26GST analysis showed that the homology was very high between isolate from Indonesia and several isolates from China that known still susceptible to praziquantel.. The results indicate that there was no evidence for reduced susceptibility of S. japonicum to praziquantel despite its extensive use in the endemic areas of Napu and Lindu for more than 20 years.Keywords : Drug Resistance, Praziquantel, Schistosoma Japonicum, SchistosomiasisAbstrak Schistosomiasis di Indonesia ditemukan di Dataran Tinggi Lindu, Napu, dan Bada Sulawesi Tengah. Schistosomiasis masih menjadi masalah kesehatan dengan angka kasus yang berfluktuasi setiap tahun. Obat praziquantel telah digunakan secara massal sejak tahun 1980an, sehingga perlu dilakukan analisis kerentanan cacing Schistosoma japonicumterhadap praziquantel. Penelitian ini  bertujuan  untuk  mengidentifikasi  kerentanan  cacing S. japonicum terhadap praziquantel di Dataran Tinggi Lindu, dengan analisis secara molekuler gen penyandi

  20. Cloning and expression in Escherichia coli of a new gene of Schistosoma japonicum encoding casein kinase Ⅱ beta subunit

    Institute of Scientific and Technical Information of China (English)

    彭寨玉; 余新炳; 吴忠道; 徐劲; 吴德; 李孜

    2004-01-01

    Background Nowadays it is now a focus topic in schistosomiasis research to find ideal vaccine candidates and new drug targets for developing anti-schistosomiasis vaccine. We cloned a new gene, casein kinase Ⅱ beta subunit, of Schistosoma japonicum (S. japonicum) and express it in Escherichia coli (E.coli).Methods The ESTs obtained in our laboratory were analyzed by homologous searching, and a new gene was recognized. The full-length cDNA of the new gene was obtained by joining the 3'RACE PCR fragment and the EST clone. To express the new gene, the cDNA was cloned into pGEX-4T-1 vector and then transformed into E.coli JM109. The recombinant protein was analyzed by SDS-PAGE and Western-blot. Results A 908 bp cDNA was isolated from S. japonicum and identified to be casein kinase Ⅱ beta subunit gene by sequence analysis. The open reading frame of the gene encodes a protein of 217 amino acids exhibiting 75.8%, 75.8%, 73.9%, 68.2%, 51.6% identity to the amino acids sequence of the corresponding genes of Homo sapiens (H. sapiens), Xenopus laevi (X. laevi), Drosophila melanogaster (D. melanogaster), Caenorhabditis elegan (C. elegan), and Schizosaccharomyces pombe (S. promber) respectively. The predicted molecular weight of the protein was 24.921 kDa. The new cDNA sequence had been submitted to GenBank, and its accession number is AY241391. This cDNA was subcloned into the pGEX-4T-1 vector and expressed in E.coli JM109.The recombinant protein could be recognized by the S. japonicum infected rabbit serum. Conclusion The full-length cDNA sequences encoding S. japonicum casein kinase Ⅱ beta subunit were firstly sequenced, cloned, and expressed in E.coli.

  1. 2-Cys peroxiredoxins from Schistosoma japonicum: the expression profile and localization in the life cycle.

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    Kumagai, Takashi; Osada, Yoshio; Kanazawa, Tamotsu

    2006-10-01

    Peroxiredoxin (Prx) is known to be an antioxidant protein that protects the organisms against various oxidative stresses and functions as a signal transductor. Here, we determined the full-length cDNA sequences of three types of Prx from an Asian blood fluke, Schistosoma japonicum: Prx-1, Prx-2 and Prx-3. According to the deduced amino acid sequences, only Prx-3 had a mitochondria-targeting sequence. Using RT-PCR, it was shown that these Prx genes were constitutively expressed in the eggs, cercariae and adult worms of the schistosome. Western blot analysis using antisera specific for each Prx revealed that all the three Prx proteins existed in these developmental stages. By immunolocalization analysis, Prx-1 existed on the surface of a miracidium and in the space between a miracidium and an eggshell. Furthermore, Prx-1 was deposited in the host tissues around the eggs. In adult worms, Prx-1 was not only expressed in the tegument, but also contained in their excretory/secretory products. The surface of the 7 day-schistosomula was stained with anti-Prx-1 antiserum. On the other hand, Prx-2 only existed inside the miracidia in eggs. In addition, Prx-2 was mainly detected in the sub-tegumental tissues, parenchyma, vitelline gland and gut epithelium of the adult worms, but was not detected in the tegument of adults and schistosomula. Taken together with previous reports by other investigators, these data suggest that Prx-1 acts to protect the parasite against the ROS produced by host immune cells, and that Prx-2 plays important roles in intracellular redox signaling and/or in the reduction of ROS generated through the hemoglobinolytic process in the digestive tract. PMID:16806527

  2. Effectiveness of synthetic trioxolane OZ78 against Schistosoma japonicum in mice and rabbits.

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    Xiao, Shu-Hua; Xue, Jian; Mei, Jing-Yan; Jiao, Pei-Ying

    2012-06-01

    Antischistosomal activities of a synthetic peroxide OZ78 (an ozonide carboxylic acid) against Schistosoma japonicum have been studied in mice and rabbits. Among 132 mice used, 30 of them were infected with 80-100 S. japonicum cercariae for collection of juvenile and adult schistosomes applied in in vitro tests. The remaining 102 mice were infected with 40 schistosome cercariae used for experimental treatment. Other 13 rabbits infected each with 200 schistosome cercariae were treated orally with OZ78 42 days post-infection. Most treated mice and rabbits were sacrificed 4 weeks post-treatment to collect residual schistosomes for evaluation of the drug efficacy. OZ78 and its sodium salt (OZ78-Na salt) 10-60 μg/mL alone exhibited no in vitro effect against day 14, day 21 schistosomula, and day 35 adult schistosomes. But OZ78 and OZ78-Na salt 10 and 20 μg/mL together with hemin 80 μg/mL showed decrease in worm motor activity and severe damage to the worm tegument and intestine, and all worms died within 3 days post-incubation. After infected mice were treated orally with OZ78 at a single dose of 400 mg/kg for 1 day, 34.9% of the worms shifted to the liver. Three and 7 days post-treatment, 100% of the worms were recovered from the liver. Fourteen days post-treatment, 92.3% of the worms still remained in the liver and 7.7% of the worms returned back to the mesenteric veins. Male and female worms shifted to the liver revealed in apparent shrinkage, degeneration of worm body, depigmentation in gut, and disappearance of ova in the uterus of some female worms. Meanwhile, dead worm and dead worm fragments were found in the liver tissues. In mice infected with various stages of schistosomes and treated orally with single OZ78 400 mg/kg, moderate or potential effect of the drug against day 0 (3-h-old worm), day 7, day 14, and day 21 juvenile worms and day 28, day 35 as well as day 42 adult worms were observed, the differences of total or female worm burdens between each

  3. Effect of photoperiod change on chronobiology of cercarial emergence of Schistosoma japonicum derived from hilly and marshy regions of China.

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    Wang, Su-Rong; Zhu, Yuan-Jian; Ge, Qing-Peng; Yang, Meng-Jia; Huang, Ji-Lei; Huang, Wen-Qiao; Zhuge, Hong-Xiang; Lu, Da-Bing

    2015-12-01

    The chronobiology of cercarial emergence appeared to be a genetically controlled behavior, adapted to definitive host species, for schistosome. However, a few physiological and ecological factors, for example the change of photoperiod, were reported to affect the rhythmic emergence of cercariae. Therefore, the effect of photoperiod change on cercarial emergence of two Schistosoma japonicum isolates, the hilly and the marshland, was investigated. Four shedding experiments each under a different photoperiod were conducted. Under a natural photoperiod, two distinct shedding modes, one from the hilly region and one from the marshland, were observed. Under a reversed photoperiod, the regular pattern (i.e. under a natural photoperiod) of S. japonicum cercarial emergence was reversed for the marshland isolate and disappeared for the hilly isolate. With an input of a 2 h darkness from 7am to 9am, the cercarial emergence peak were delayed for the two isolates; whereas with an input of a 2 h darkness from 5pm to 7pm, neither effect on the cercarial emergence rhythm was observed. The total cercariae emerged for both parasite isolates varied with a different photoperiod. The results indicate that the change of photoperiod could affect the chronobiology of S japonicum cercarial emergence. PMID:26484419

  4. Adenovirus-mediated over-expression of Septin4 ameliorates hepatic fibrosis in mouse livers infected with Schistosoma japonicum.

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    He, Xue; Bao, Jing; Chen, Jinling; Sun, Xiaolei; Wang, Jianxin; Zhu, Dandan; Song, Ke; Peng, Wenxia; Xu, Tianhua; Duan, Yinong

    2015-12-01

    Septin4 (Sept4) belongs to Septin family and may be involved in apoptosis, vesicle trafficking and other cell processes. In this study, we attempted to investigate the effect of Sept4 in hepatic fibrosis induced by Schistosoma japonicum. ICR mice infected with S. japonicum for 12weeks were treated with PBS, Ad-ctr and Ad-Sept4, respectively. All mice were killed at 2weeks after injection, and the changes in the fibrotic livers were detected via H&E staining, Sirius red staining, qRT-PCR, western blot and TUNEL analysis. In addition, pcDNA3.1-Sept4 plasmid was transfected into LX-2 cells to observe the effect of Sept4 on apoptosis of HSCs in vitro. Ad-Sept4 could ameliorate liver fibrosis, as detected by H&E staining and Sirius red staining. The number of TUNEL-positive cells was increased in the Ad-Sept4 treated group. The expression of Sept4 and cleaved-caspase-3 were all augmented, while the expression of α-SMA, Col1α1 and IL-13 were reduced in the Ad-Sept4 treated group, compared with that expressed in the Ad-ctr group. Over-expression of Sept4 in LX-2 cells could promote apoptosis of LX-2 cells in vitro. In conclusion, Ad-Sept4 can attenuate the development of liver fibrosis induced by S. japonicum through apoptosis. PMID:26190030

  5. Genetic variation between Schistosoma japonicum lineages from lake and mountainous regions in China revealed by resequencing whole genomes.

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    Yin, Mingbo; Liu, Xiao; Xu, Bin; Huang, Jian; Zheng, Qi; Yang, Zhong; Feng, Zheng; Han, Ze-Guang; Hu, Wei

    2016-09-01

    Schistosoma infection is a major cause of morbidity and mortality worldwide. Schistosomiasis japonica is endemic in mainland China along the Yangtze River, typically distributed in two geographical categories of lake and mountainous regions. Study on schistosome genetic diversity is of interest in respect of understanding parasite biology and transmission, and formulating control strategy. Certain genetic variations may be associated with adaptations to different ecological habitats. The aim of this study is to gain insight into Schistosoma japonicum genetic variation, evolutionary origin and associated causes of different geographic lineages through examining homozygous Single Nucleotide Polymorphisms (SNPs) based on resequenced genome data. We collected S. japonicum samples from four sites, three in the lake regions (LR) of mid-east (Guichi and Tonglin in Anhui province, Laogang in Hunan province) and one in mountainous region (MR) (Xichang in Sichuan province) of south-west of China, resequenced their genomes using Next Generation Sequencing (NGS) technology, and made use of the available database of S. japonicum draft genomic sequence as a reference in genome mapping. A total of 14,575 SNPs from 2059 genes were identified in the four lineages. Phylogenetic analysis confirmed significant genetic variation exhibited between the different geographical lineages, and further revealed that the MR Xichang lineage is phylogenetically closer to LR Guich lineage than to other two LR lineages, and the MR lineage might be evolved from LR lineages. More than two thirds of detected SNPs were nonsynonymous; functional annotation of the SNP-containing genes showed that they are involved mainly in biological processes such as signaling and response to stimuli. Notably, unique nonsynonymous SNP variations were detected in 66 genes of MR lineage, inferring possible genetic adaption to mountainous ecological condition. PMID:27207135

  6. Global expression analysis revealed novel gender-specific gene expression features in the blood fluke parasite Schistosoma japonicum.

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    Xianyu Piao

    Full Text Available BACKGROUND: Schistosoma japonicum is one of the remarkable Platyhelminths that are endemic in China and Southeast Asian countries. The parasite is dioecious and can reside inside the host for many years. Rapid reproduction by producing large number of eggs and count-react host anti-parasite responses are the strategies that benefit long term survival of the parasite. Praziquantel is currently the only drug that is effective against the worms. Development of novel antiparasite reagents and immune-prevention measures rely on the deciphering of parasite biology. The decoding of the genomic sequence of the parasite has made it possible to dissect the functions of genes that govern the development of the parasite. In this study, the polyadenylated transcripts from male and female S. japonicum were isolated for deep sequencing and the sequences were systematically analysed. RESULTS: First, the number of genes actively expressed in the two sexes of S. japonicum was similar, but around 50% of genes were biased to either male or female in expression. Secondly, it was, at the first time, found that more than 50% of the coding region of the genome was transcribed from both strands. Among them, 65% of the genes had sense and their cognate antisense transcripts co-expressed, whereas 35% had inverse relationship between sense and antisense transcript abundance. Further, based on gene ontological analysis, more than 2,000 genes were functionally categorized and biological pathways that are differentially functional in male or female parasites were elucidated. CONCLUSIONS: Male and female schistosomal parasites differ in gene expression patterns, many metabolic and biological pathways have been identified in this study and genes differentially expressed in gender specific manner were presented. Importantly, more than 50% of the coding regions of the S. japonicum genome transcribed from both strands, antisense RNA-mediated gene regulation might play a critical

  7. Comparative Analysis of 18S and 28S rDNA Sequences of Schistosoma japonicum from Mainland China, the Philippines and Japan

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    G.H. Zhao

    2011-01-01

    Full Text Available In the present study, a portion of the 18S and 28S ribosomal DNA (rDNA sequences of 35 Schistosoma japonicum isolates representing three geographical strains from mainland China, the Philippines and Japan were amplified and compared and phylogenetic relationships were also reconstructed by Unweighted Pair-Group Method with Arithmetic averages (UPGMA using combined 18S and 28S rDNA sequences as well as the corresponding sequences of other species belonging to the Schistosoma genus available in the public database. The results indicated that the partial 18S and 28S rDNA sequences of all S. japonicum isolates were 745 and 618 bp, respectively and displayed low genetic variation among S. japonicum strains and isolates. Phylogenetic analysis revealed that the combined 18S and 28S rDNA sequences were not able to distinguish S. japonicum isolates from three geographical origins but provided an effective molecular marker for the inter-species phylogenetic analysis and differential identification of different Schistosoma species.

  8. Ultrastructural observation and gene expression profiling of Schistosoma japonicum derived from two natural reservoir hosts, water buffalo and yellow cattle.

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    Jianmei Yang

    Full Text Available Water buffalo and yellow cattle are the two of the most important natural reservoir hosts for Schistosoma japonicum in endemic areas of China, although their susceptibility differs, with water buffalo being less conducive to the growth and development of S. japonicum. Results from the current study show that the general morphology and ultrastructure of adult schistosomes derived from the two hosts also differed. Using high-throughput microarray technology, we also compared the gene expression profiles of adult schistosomes derived from the two hosts. We identified genes that were differentially expressed in worms from the two natural hosts. Further analysis revealed that genes associated with protein kinase and phosphatase, the stimulus response, and lipid and nucleotide metabolism were overexpressed, whereas genes associated with reproduction, anatomical structure morphogenesis and multifunctional motif were underexpressed in schistosomes from water buffalo. These differentially expressed genes were mainly involved in nucleotide, energy, lipid metabolism, energy metabolism, transcription, transport and signaling pathway. This suggests that they are key molecules affecting the survival and development of schistosomes in different natural host species. The results of this study add to current understanding of the interplay between parasites and their natural hosts, and provide valuable information for the screening of vaccine candidates or new drug targets against schistosomiasis in the natural reservoir hosts in endemic areas.

  9. Correlative and dynamic imaging of the hatching biology of Schistosoma japonicum from eggs prepared by high pressure freezing.

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    Malcolm K Jones

    Full Text Available BACKGROUND: Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with freshwater, but the mechanisms of activation and hatching are poorly understood. In view of the lack of knowledge of the behaviour of egg hatching in schistosomes, we undertook a detailed dynamic and correlative study of the hatching biology of Schistosoma japonicum. METHODOLOGY/PRINCIPAL FINDINGS: Hatching eggs of S. japonicum were studied using correlative light and electron microscopy (EM. The hatching behaviour was recorded by video microscopy. EM preparative methods incorporating high pressure freezing and cryo-substitution were used to investigate ultrastructural features of the miracidium and extra-embryonic envelopes in pre-activated and activated eggs, and immediately after eggshell rupture. Lectin cytochemistry was performed on egg tissues to investigate subcellular location of specific carbohydrate groups. CONCLUSIONS/SIGNIFICANCE: The hatching of S. japonicum eggs is a striking phenomenon, whereby the larva is liberated explosively while still encapsulated within its sub-shell envelopes. The major alterations that occur in the egg during activation are scission of the outer envelope-eggshell boundary, autolysis of the cellular inner envelope, and likely hydration of abundant complex and simple polysaccharides in the lacunal space between the miracidial larva and surrounding envelopes. These observations on hatching provide insight into the dynamic activity of the eggs and the biology of schistosomes within the host.

  10. Molecular characterization of thyroid hormone receptor beta from Schistosoma japonicum and assessment of its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice

    OpenAIRE

    Qiu Chunhui; Liu Shengfa; Hong Yang; Fu Zhiqiang; Wei Meimei; Ai Dezhou; Lin Jiaojiao

    2012-01-01

    Abstract Background Thyroid hormones (TH) modulate growth, development and differentiation and metabolic processes by interacting with thyroid hormone receptors (THRs). The purpose of this study was to identify a novel thyroid hormone receptor beta encoding gene of Schistosoma japonicum (SjTHRβ) and to investigate its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice. Methods The full-length cDNA sequence of SjTHRβ, its gene organization, and its transcript level...

  11. Multiple vaccinations with UV- attenuated cercariae in pig enhance protective immunity against Schistosoma japonicum infection as compared to single vaccination

    OpenAIRE

    Zhang Donghui; Wu Jingjiao; Gao Yanan; Wu Haiwei; Tian Fang; Lin Dandan; Ji Minjun; McManus Donald P; Driguez Patrick; Wu Guanling

    2011-01-01

    Abstract Background Schistosomiasis japonica is a major public health problem in the endemic areas of China, the Philippines, and Indonesia. To date, a vaccine has not been developed against this disease but immunization with UV-attenuated cercariae can induce a high level of protective immunity in Landrace/Yorkshire/Duroc crossbred pigs. To compare the efficacy of a single vaccination and multiple vaccinations with UV-attenuated Schistosoma japonicum cercariae, two groups of pigs received ei...

  12. Synthesis, Bioactivity Evaluation, and Toxicity Assessment of Novel Salicylanilide Ester Derivatives as Cercaricides against Schistosoma japonicum and Molluscicides against Oncomelania hupensis

    Science.gov (United States)

    Wang, Weisi; Qin, Zhiqiang; Zhu, Dan; Wei, Yufen; Li, Shizhu

    2015-01-01

    A series of novel salicylanilide ester derivatives were synthesized, characterized, and evaluated for cercaricidal potential against Schistosoma japonicum and molluscicidal potential against Oncomelania hupensis. Four derivatives exhibited remarkable cercaricidal activity superior to that of niclosamide. Among them, the most active compound, 4-chloro-2-((2-methoxy-4-nitrophenyl)carbamoyl)phenyl 4-methoxybenzoate (compound 4c), showed a marked minimum effective cercaricidal concentration as low as 0.43 μM and significant molluscicidal activity, with a 50% lethal concentration (LC50) of 0.206 g/m2. Particularly, compound 4c displayed 88-fold decreased fish toxicity on Danio rerio and 44-fold reduced cytotoxicity on human kidney HEK293 cells in comparison with the toxicity of niclosamide. The results indicated that 4c could serve as a promising drug candidate, with environmental safety properties, against Schistosoma japonicum at transmission stages. The preliminary molecular mechanism of target compounds in Schistosoma japonicum cercariae was also investigated. Salicylanilide ester derivatives exhibited an inhibitory effect on nitric oxide synthase (NOS) but no effect on lactate dehydrogenase (LDH) and acetylcholinesterase (AChE), and a strong and significant correlation between NOS inhibitory efficacy and cercaricidal activity was observed. In addition, 4c could downregulate the expression of NOS in a dose-dependent manner. These results suggested that NOS was probably one of the drug targets of salicylanilide esters. PMID:26503661

  13. Synthesis, Bioactivity Evaluation, and Toxicity Assessment of Novel Salicylanilide Ester Derivatives as Cercaricides against Schistosoma japonicum and Molluscicides against Oncomelania hupensis.

    Science.gov (United States)

    Wang, Weisi; Qin, Zhiqiang; Zhu, Dan; Wei, Yufen; Li, Shizhu; Duan, Liping

    2016-01-01

    A series of novel salicylanilide ester derivatives were synthesized, characterized, and evaluated for cercaricidal potential against Schistosoma japonicum and molluscicidal potential against Oncomelania hupensis. Four derivatives exhibited remarkable cercaricidal activity superior to that of niclosamide. Among them, the most active compound, 4-chloro-2-((2-methoxy-4-nitrophenyl)carbamoyl)phenyl 4-methoxybenzoate (compound 4c), showed a marked minimum effective cercaricidal concentration as low as 0.43 μM and significant molluscicidal activity, with a 50% lethal concentration (LC50) of 0.206 g/m(2). Particularly, compound 4c displayed 88-fold decreased fish toxicity on Danio rerio and 44-fold reduced cytotoxicity on human kidney HEK293 cells in comparison with the toxicity of niclosamide. The results indicated that 4c could serve as a promising drug candidate, with environmental safety properties, against Schistosoma japonicum at transmission stages. The preliminary molecular mechanism of target compounds in Schistosoma japonicum cercariae was also investigated. Salicylanilide ester derivatives exhibited an inhibitory effect on nitric oxide synthase (NOS) but no effect on lactate dehydrogenase (LDH) and acetylcholinesterase (AChE), and a strong and significant correlation between NOS inhibitory efficacy and cercaricidal activity was observed. In addition, 4c could downregulate the expression of NOS in a dose-dependent manner. These results suggested that NOS was probably one of the drug targets of salicylanilide esters. PMID:26503661

  14. Field Detection of Schistosoma japonicum Cercariae in Environmental Water Samples by Quantitative PCR ▿ †

    OpenAIRE

    Worrell, Caitlin; Xiao, Ning; Vidal, Jorge E.; Chen, Lin; Zhong, Bo; Remais, Justin

    2011-01-01

    A species-specific quantitative PCR (qPCR) assay was combined with two novel water-sampling methods and compared with the mouse bioassay for the quantitative detection of S. japonicum in surface waters. The novel methods were capable of capturing cercariae and, with subsequent analysis through qPCR, detecting the presence of a minimum of 1 cercaria.

  15. Utilization of ELISA using thioredoxin peroxidase-1 and tandem repeat proteins for diagnosis of Schistosoma japonicum infection among water buffaloes.

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    Jose Ma M Angeles

    Full Text Available BACKGROUND: The presence of animal reservoirs in Schistosoma japonicum infection has been a major obstacle in the control of schistosomiasis. Previous studies have proven that the inclusion of control measures on animal reservoir hosts for schistosomiasis contributed to the decrease of human cases. Animal surveillance should therefore be included to strengthen and improve the capabilities of current serological tests. METHODOLOGY/PRINCIPAL FINDINGS: Thioredoxin peroxidase-1 (SjTPx-1 and four tandem repeat proteins (Sj1TR, Sj2TR, Sj4TR, Sj7TR were initially evaluated against human sera. The previous test showed high sensitivity and specificity for antibody detection against SjTPx-1 and Sj7TR. In this study, the immunodiagnostic potential of these recombinant proteins was evaluated using enzyme-linked immunoassay on 50 water buffalo serum samples collected in Cagayan, the Philippines as compared with the soluble egg antigen (SEA. For specificity, 3 goat serum samples positive with Fasciola hepatica were used and among the antigens used, only SEA showed cross-reaction. Stool PCR targeting the S. japonicum 82 bp mitochondrial NAD 1 gene was done to confirm the true positives and served as the standard test. Twenty three samples were positive for stool PCR. SjTPx-1 and Sj1TR gave the highest sensitivity among the recombinant proteins tested for water buffalo samples with 82.61% and 78.26% respectively which were higher than that of SEA (69.57%. CONCLUSIONS/SIGNIFICANCE: These results prove that SjTPx-1 works both for humans and water buffaloes making it a good candidate antigen for zoonotic diagnosis. Sj1TR showed good results for water buffaloes and therefore can also be used as a possible candidate for detecting animal schistosome infection.

  16. Proteomic Analysis on Cercariae and Schistosomula in Reference to Potential Proteases Involved in Host Invasion of Schistosoma japonicum Larvae.

    Science.gov (United States)

    Liu, Mu; Ju, Chuan; Du, Xiao-Feng; Shen, Hai-Mo; Wang, Ji-Peng; Li, Jian; Zhang, Xu-Min; Feng, Zheng; Hu, Wei

    2015-11-01

    Schistosomiasis is a parasitic zoonosis posing great threat to human health. The infection is acquired by larval cercariae penetrating host skin and transforming into juveniles, schistosomula. Proteolytic enzymes secreted from the cercarial acetabular glands are known to aid to the skin penetration, but molecular mechanisms remain largely unclear. To profile the protein composition and identify potential invasive proteases, we developed a new method for simulating cercarial transformation and collecting schistosomula, and for the first time, we compared the proteomes of Schistosoma japonicum cercariae and schistosomula by using in-gel shotgun proteomic analysis. Totally, 1972 proteins were identified in association with ten main biological processes based on Gene Ontology analysis; 46 proteases were detected in cercariae, and among them, 25 proteases disappeared after penetrated. Notably, leishmanolysins and serine and cysteine proteases were found abundant but differentially expressed. Recombinant serine protease SjCE2b and cysteine protease SjCB2 were produced and used for validation of native proteins. Immunofluorescence and Western blotting assays detected SjCE2b and SjCB2 in cercariae but not in schistosomula, suggesting the two enzymes might be consumed upon skin migration. Our data comprehensively chart the proteomic changes during cercarial invasion, revealing the potential proteases involved, providing a platform for the development of molecular anti-infection strategy. PMID:26370134

  17. Immunoglobulins and complement in the skin of Rhesus monkeys immunized with X-irradiated cercariae of Schistosoma japonicum

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    Li-Hsue, S.Y.; Hsue, H.F.; Hanson, H.O.

    1981-01-01

    Skin sections of Rhesus monkeys immunized with X-irradiated Schistosoma japonicum cercariae were stained by an unlabeled antibody enzyme method for the detection of IgG, IgM, IgA, IgE, and C3. While all of them could be found in the skin lesions, their distribution patterns varied with time and reactions. In whealing reaginic reactions, IgE appeared prominent, having an affinity to the mast cells. In Arthus-like reactions, IgG was predominant. IgG complexes were found on the schistosomula, on the walls of blood vessels, and in granulocytes near the schistosomula. In the late stage of Arthus-like reactions and in delayed hypersensitive reactions, IgA was predominant in granulocytes, mononuclear cells, and macrophages. Characteristics of each immunoglobulin pattern seemed to reflect its function in the effector mechanism. It may be speculated that these immunoglobulins and C3, together with effector cells, synergistically and sequentially destroy schistosomula in the skin.

  18. Immunoglobulins and complement in the skin of Rhesus monkeys immunized with X-irradiated cercariae of Schistosoma japonicum

    International Nuclear Information System (INIS)

    Skin sections of Rhesus monkeys immunized with X-irradiated Schistosoma japonicum cercariae were stained by an unlabeled antibody enzyme method for the detection of IgG, IgM, IgA, IgE, and C3. While all of them could be found in the skin lesions, their distribution patterns varied with time and reactions. In whealing reaginic reactions, IgE appeared prominent, having an affinity to the mast cells. In Arthus-like reactions, IgG was predominant. IgG complexes were found on the schistosomula, on the walls of blood vessels, and in granulocytes near the schistosomula. In the late stage of Arthus-like reactions and in delayed hypersensitive reactions, IgA was predominant in granulocytes, mononuclear cells, and macrophages. Characteristics of each immunoglobulin pattern seemed to reflect its function in the effector mechanism. It may be speculated that these immunoglobulins and C3, together with effector cells, synergistically and sequentially destroy schistosomula in the skin. (orig.)

  19. 3-oxoacyl-ACP reductase from Schistosoma japonicum: integrated in silico-in vitro strategy for discovering antischistosomal lead compounds.

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    Jian Liu

    Full Text Available BACKGROUND: Schistosomiasis is a disease caused by parasitic worms and more than 200 million people are infected worldwide. The emergence of resistance to the most commonly used drug, praziquantel (PZQ, makes the development of novel drugs an urgent task. 3-oxoacyl-ACP reductase (OAR, a key enzyme involved in the fatty acid synthesis pathway, has been identified as a potential drug target against many pathogenic organisms. However, no research on Schistosoma japonicum OAR (SjOAR has been reported. The characterization of the SjOAR protein will provide new strategies for screening antischistosomal drugs that target SjOAR. METHODOLOGY/PRINCIPAL FINDINGS: After cloning the SjOAR gene, recombinant SjOAR protein was purified and assayed for enzymatic activity. The tertiary structure of SjOAR was obtained by homology modeling and 27 inhibitor candidates were identified from 14,400 compounds through molecular docking based on the structure. All of these compounds were confirmed to be able to bind to the SjOAR protein by BIAcore analysis. Two compounds exhibited strong antischistosomal activity and inhibitory effects on the enzymatic activity of SjOAR. In contrast, these two compounds showed relatively low toxicity towards host cells. CONCLUSIONS/SIGNIFICANCE: The work presented here shows the feasibility of isolation of new antischistosomal compounds using a combination of virtual screening and experimental validation. Based on this strategy, we successfully identified 2 compounds that target SjOAR with strong antischistosomal activity but relatively low cytotoxicity to host cells.

  20. The Differential Expression of Immune Genes between Water Buffalo and Yellow Cattle Determines Species-Specific Susceptibility to Schistosoma japonicum Infection.

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    Jianmei Yang

    Full Text Available Water buffalo are less susceptible to Schistosoma japonicum infection than yellow cattle. The factors that affect such differences in susceptibility remain unknown. A Bos taurus genome-wide gene chip was used to analyze gene expression profiles in the peripheral blood of water buffalo and yellow cattle pre- and post-infection with S. japonicum. This study showed that most of the identified differentially expressed genes (DEGs between water buffalo and yellow cattle pre- and post-infection were involved in immune-related processes, and the expression level of immune genes was lower in water buffalo. The unique DEGs (390 in yellow cattle were mainly associated with inflammation pathways, while the unique DEGs (2,114 in water buffalo were mainly associated with immune-related factors. The 83 common DEGs may be the essential response genes during S. japonicum infection, the highest two gene ontology (GO functions were associated with the regulation of fibrinolysis. The pathway enrichment analysis showed that the DEGs constituted similar immune-related pathways pre- and post-infection between the two hosts. This first analysis of the transcriptional profiles of natural hosts has enabled us to gain new insights into the mechanisms that govern their susceptibility or resistance to S. japonicum infections.

  1. A Bayesian-based approach for spatio-temporal modeling of county level prevalence of Schistosoma japonicum infection in Jiangsu province, China.

    Science.gov (United States)

    Yang, Guo-Jing; Vounatsou, Penelope; Zhou, Xiao-Nong; Tanner, Marcel; Utzinger, Jürg

    2005-02-01

    Spatio-temporal variations of Schistosoma japonicum infection risk in Jiangsu province, China, were examined and the relationships between key climatic factors and infection prevalence at the county level were determined. The parasitological data were collected annually by means of cross-sectional surveys carried out in 47 counties from 1990 to 1998. Climatic factors, namely land surface temperature (LST) and normalized difference vegetation index (NDVI), were obtained from remote sensing satellite sensors. Bayesian spatio-temporal models were employed to analyze the data. The best fitting model showed that spatial autocorrelation in Jiangsu province decreased dramatically from 1990 to 1992 and increased gradually thereafter. A likely explanation of this finding arises from the large-scale administration of praziquantel for morbidity control of schistosomiasis. Our analysis suggested a negative association between NDVI and risk of S. japonicum infection. On the other hand, an increase in LST contributed to a significant increase in S. japonicum infection prevalence. We conclude that combining geographic information system, remote sensing and Bayesian-based statistical approaches facilitate integrated risk modeling of S. japonicum, which in turn is of relevance for allocation of scarce resources for control of schistosomiasis japonica in Jiangsu province and elsewhere in China, where the disease remains of public health and economic significance. PMID:15710436

  2. Cloning, expression and protective immunity evaluation of the full-length cDNA encoding succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum

    Institute of Scientific and Technical Information of China (English)

    YU JunLong; WANG ShiPing; LI WenKai; DAI Gan; XU ShaoRui; HE Zhuo; PENG XianChu; ZHOU SongHua; LIU XueQin

    2007-01-01

    1071-bp fragment was obtained from the Schistosoma japonicum (Chinese strain) adult cDNA library after the 3' and 5' ends of the incomplete expression sequence tag (EST) of succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum (SjSDISP) were amplified by the anchored PCR with 2pairs of primers designed according to the EST of SjSDISP and the sequence of multiclone sites of the library vector. Sequence analysis indicated that the fragment was a full-length cDNA with a complete open reading frame (ORF), encoding 278 amino acid residues. The fragment was cloned into prokaryotic expression vector pQE30, and subsequently sequenced and expressed in Escherichia coll.SDS-PAGE and Western-blot analyses showed that the recombinant protein was about 32 kD and could be recognized by the polyclonal antisera from rabbits immunized with Schistosoma japonicum adult worm antigen. Compared with the FCA controls, mice vaccinated with rSjSDISP (test) or rSjGST (positive control) all revealed high levels of specific antibody and significant reduction in worm burden, liver eggs per gram (LEPG), fecal eggs per gram (FEPG) and intrauterine eggs. These results suggest that SjSDISP may be a novel and partially protective vaccine candidate against schistosomiasis. In contrast to the worm burden reduction rate, the higher degree of egg reduction rate in the test group also suggested that SjSDISP vaccine may primarily play a role in anti-embryonation or anti-fecundity immunity.

  3. Combined IL-12 Plasmid and Recombinant SjGST Enhance the Protective and Anti-pathology Effect of SjGST DNA Vaccine Against Schistosoma japonicum.

    OpenAIRE

    Po-Ching Cheng; Ching-Nan Lin; Shih-Yi Peng; Tsung-Fu Kang; Kin-Mu Lee

    2016-01-01

    Schistosomiasis is listed as one of most important tropical diseases and more than 200 million people are estimated to be infected. Development of a vaccine is thought to be the most effective way to control this disease. Recombinant 26-kDa glutathione S-transferase (rSjGST) has previously been reported to achieve a worm reduction rate of 42–44%. To improve the efficiency of the vaccine against Schistosoma japonicum, we immunized mice with a combination of pcDNA vector-encoded 26-kDa SjGST (p...

  4. Co-ordinated gene expression in the liver and spleen during Schistosoma japonicum infection regulates cell migration.

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    Melissa L Burke

    Full Text Available Determining the molecular events induced in the spleen during schistosome infection is an essential step in better understanding the immunopathogenesis of schistosomiasis and the mechanisms by which schistosomes modulate the host immune response. The present study defines the transcriptional and cellular events occurring in the murine spleen during the progression of Schistosoma japonicum infection. Additionally, we compared and contrasted these results with those we have previously reported for the liver. Microarray analysis combined with flow cytometry and histochemistry demonstrated that transcriptional changes occurring in the spleen were closely related to changes in cellular composition. Additionally, the presence of alternatively activated macrophages, as indicated by up-regulation of Chi3l3 and Chi3l4 and expansion of F4/80(+ macrophages, together with enhanced expression of the immunoregulatory genes ANXA1 and CAMP suggests the spleen may be an important site for the control of S. japonicum-induced immune responses. The most striking difference between the transcriptional profiles of the infected liver and spleen was the contrasting expression of chemokines and cell adhesion molecules. Lymphocyte chemokines, including the homeostatic chemokines CXCL13, CCL19 and CCL21, were significantly down-regulated in the spleen but up-regulated in the liver. Eosinophil (CCL11, CCL24, neutrophil (CXCL1 and monocyte (CXCL14, CCL12 chemokines and the cell adhesion molecules VCAM1, NCAM1, PECAM1 were up-regulated in the liver but unchanged in the spleen. Chemokines up-regulated in both organs were expressed at significantly higher levels in the liver. Co-ordinated expression of these genes probably contributes to the development of a chemotactic signalling gradient that promotes recruitment of effector cells to the liver, thereby facilitating the development of hepatic granulomas and fibrosis. Together these data provide, for the first time, a

  5. Novel T-cell epitopes on Schistosoma japonicum SjP40 protein and their preventive effect on allergic asthma in mice.

    Science.gov (United States)

    Ren, Jiling; Hu, Lizhi; Yang, Jing; Yang, Liang; Gao, Fei; Lu, Ping; Fan, Mengyu; Zhu, Yunjuan; Liu, Junyan; Chen, Lingling; Gupta, Shimpy; Yang, Xi; Liu, Peimei

    2016-05-01

    Allergic asthma is a chronic inflammatory disease mediated by Th2 cell immune responses. Currently, immunotherapies based on immune deviation are attractive, preventive, and therapeutic strategies for asthma. Many studies have shown that intracellular bacterial infections such as mycobacteria and their components can suppress asthmatic reactions by enhancing Th1 responses, while helminth infections and their proteins can inhibit allergic asthma via immune regulation. However, some helminth proteins such as SmP40, the major egg antigen of Schistosoma mansoni, are found as Th1 type antigens. Using a panel of overlapping peptides, we identified T-cell epitopes on SjP40 protein of Schistosoma japonicum, which can induce Th1 cytokine and inhibit the production of Th2 cytokines and airway inflammation in a mouse model of allergic asthma. These results reveal a novel form of immune protective mechanism, which may play an important role in the modulating effect of helminth infection on allergic asthmatic reactions. PMID:26840774

  6. Using the local immune response from the natural buffalo host to generate an antibody fragment library that binds the early larval stages of Schistosoma japonicum.

    Science.gov (United States)

    Hosking, Christopher G; Driguez, Patrick; McWilliam, Hamish E G; Ilag, Leodevico L; Gladman, Simon; Li, Yuesheng; Piedrafita, David; McManus, Donald P; Meeusen, Els N T; de Veer, Michael J

    2015-09-01

    Antibodies isolated from the local draining inguinal lymph node of field exposed-water buffaloes following challenge with Schistosoma japonicum cercariae showed high reactivity towards S. japonicum antigen preparations and bound specifically to formaldehyde-fixed S. japonicum schistosomules. Using this specific local immune response we produced a series of single-chain antibody Fv domain libraries from the same lymph nodes. Removal of phage that cross reacted with epitopes on adult parasites yielded a single-chain antibody Fv domain-phage library that specifically bound to whole formaldehyde-fixed and live S. japonicum schistosomules. DNA sequencing indicated clear enrichment of the single-chain antibody Fv domain library for buffalo B-cell complementarity determining regions post-selection for schistosomule binding. This study also revealed that long heavy chain complementarity determining regions appear to be an important factor when selecting for antibody binding fragments against schistosomule proteins. The selected single-chain antibody Fv domain-phage were used to probe a schistosome-specific protein microarray, which resulted in the recognition of many proteins expressed across all schistosome life-cycle stages. Following absorption to adult worms, the single-chain antibody Fv domain-phage library showed significantly reduced binding to most proteins, whilst two proteins (NCBI GenBank accession numbers AY915878 and AY815196) showed increased binding. We have thus developed a unique set of host derived single-chain antibody Fv domains comprising buffalo B-cell variable regions that specifically bind to early S. japonicum life-stages. PMID:26116907

  7. Gene Gun Bombardment with DNA-Coated Golden Particles Enhanced the Protective Effect of a DNA Vaccine Based on Thioredoxin Glutathione Reductase of Schistosoma japonicum

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    Yan Cao

    2013-01-01

    Full Text Available Schistosomiasis, caused by infection with Schistosoma species, remains an important parasitic zoonosis. Thioredoxin glutathione reductase of Schistosoma japonicum (SjTGR plays an important role in the development of the parasite and for its survival. Here we present a recombinant plasmid DNA vaccine, pVAX1/SjTGR, to estimate its protection against S. japonicum in BALB/c mice. The DNA vaccine administrated by particle bombardment induced higher protection than by intramuscular injection. All animals vaccinated with pVAX1/SjTGR developed significant specific anti-SjTGR antibodies than control groups. Moreover, animals immunized by gene gun exhibited a splenocyte proliferative response, with an increase in IFN-γ and IL-4. The recombinant plasmid administrated by gene gun achieved a medium protective efficacy of 27.83–38.83% ( of worm reduction and 40.38–44.51% ( of liver egg count reduction. It suggests that different modes of administering a DNA vaccine can influence the protective efficacy induced by the vaccine. Interestingly, from the enzymatic activity results, we found that worms obtained from pVAX1/SjTGR-vaccinated animals expressed lower enzymatic activity than the control group and the antibodies weakened the enzymatic activity of SjTGR in vitro, too. It implies that the high-level antibodies may contribute to the protective effects.

  8. The development and prospect of the vaccine against Schistosoma japonicum%日本血吸虫疫苗的研究进展与展望

    Institute of Scientific and Technical Information of China (English)

    景英霞; 邵筱

    2010-01-01

    The study on vaccine against Schistosoma has been included into the program of the treat-ment and prevention on the major diseases of WHO and our country with a great progress. The history of the study on vaccines against Schistosoma has passed from dead vaccine, attenuated vaccine, sub-unit vaccine,gene engineered vaccine, nucleic acid vaccine to muhivalent affiliate vaccine. Recently, the research progress on immunologic mechanism of Schiswsoma and the genome of Schistosoma has played a very important role in the research and development of vaccine against Schistosoma. This article reviewed the development of vaccine against Schistosoma japonicum in recent 10 years.%血吸虫疫苗的研究已经纳入了WHO和我国主要疾病防治规划,并且取得了很大的进展.血吸虫疫苗的研究历史经历了从死疫苗、致弱活疫苗、亚单仲疫苗、基因工程疫苗、核酸疫苗到多价联合疫苗等的探索过程.近年来开展的血吸虫免疫机制和血吸虫基因组的研究对血吸虫疫苗的研制起到了积极的推动作用.该文主要对日本血吸虫疫苗近十年的研究进展作一综述.

  9. Schistosoma japonicum:construction of phage display antibody library and its application in the immunodiagnosis of infection

    Institute of Scientific and Technical Information of China (English)

    陈代雄; 何蔼; 詹希美; 俞慕华; 雷智刚; 孟锦绣; 李卓雅; 梁瑜; 张瑞琳

    2004-01-01

    Background A monoclonal antibody would be an effective tool for the detection of circulating antigens in the serum of patients with schistosomiasis, but the traditional way of producing monoclonal antibodies is not cost-effective. The objective of this study was to find a new method for the large-scale production of monoclonal antibodies against Schistosoma japonicum (Sj).Methods A phage display antibody library for Sj was constructed. To obtain a single-chain variable fragment antibody (scFv) against Sj, the library was screened with metabolic antigens from adult Sj worms (Sj-MAg) using enzyme-linked immunosorbent assay. The soluble scFvs selected were used to detect Sj antigens in the serum of acute and chronic schistosomiasis patients.Results Six positive clones with good reactivity to Sj-MAg were obtained from the phage display antibody library of about 1.07×106 individual clones. Only two of these six clones bound specifically to Sj-MAg and were chosen for further analysis. Specific soluble anti-Sj-MAg scFvs were produced by inducing the 2 clones with isopropyl-D-thiogalactopyranoside. The characteristics of the scFvs were then determined. The results of Western blot showed that these scFvs could bind to Sj-MAg specifically and had a molecular weight of about 31 kD. When testing serum from schistosomiasis patients with one of the two specific scFvs, its sensitivity was found to be 60% and 37% in acute and chronic patients, respectively, with a specificity of 90%. When the two specific scFvs were combined, their sensitivity was found to be 75% and 57% in acute and chronic patients, respectively, with a specificity of 85%.Conclusions The results indicate that the scFvs are potentially useful for the diagnosis of schistosomiasis. The library construction also provides a useful tool for the further screening of other antibodies for both diagnostic and immunotherapeutic applications and for epitope analysis and vaccine design.

  10. Vaccination of Goats with 31 kDa and 32 kDa Schistosoma japonicum Antigens by DNA Priming and Protein Boosting

    Institute of Scientific and Technical Information of China (English)

    Lianfei Tang; Zhijun Zhou; Yuxiao Chen; Yonghui Luo; Linqian Wang; Liyu Chen; Fushen Huang; Xianfang Zeng; Xinyuan Yi

    2007-01-01

    Two Schistosoma japonicum vaccine candidate antigens Sj 31 and Sj 32, which have shown particular promise to induce protective immunity in mice, were used to immunize goats by using a DNA priming-protein boosting strategy in present work. DNA vaccine formulations of the two antigens (VRSj31 and VRSj32) were produced and injected intramuscularly twice at a 2-week interval and then recombinant proteins (rSj31 and rSj32) together with Freund Complete Adjuvant (FCA) were used to boost the goats. The experiment was repeated in different batche cercariae. A strong anamnestic antibody response was induced after boost. A significant reduction of liver egg counts and miracidial hatching was showed in both experiments. Significant protections against challenge infection were elicited with 31.6% of percentage reduction for worm recovery in the second experiment and 20.9% in the first experiment, respectively.

  11. Optimisation of a droplet digital PCR assay for the diagnosis of Schistosoma japonicum infection: A duplex approach with DNA binding dye chemistry.

    Science.gov (United States)

    Weerakoon, Kosala G; Gordon, Catherine A; Gobert, Geoffrey N; Cai, Pengfei; McManus, Donald P

    2016-06-01

    Schistosomiasis is a chronically debilitating helminth infection with a significant socio-economic and public health impact. Accurate diagnostics play a pivotal role in achieving current schistosomiasis control and elimination goals. However, many of the current diagnostic procedures, which rely on detection of schistosome eggs, have major limitations including lack of accuracy and the inability to detect pre-patent infections. DNA-based detection methods provide a viable alternative to the current tests commonly used for schistosomiasis diagnosis. Here we describe the optimisation of a novel droplet digital PCR (ddPCR) duplex assay for the diagnosis of Schistosoma japonicum infection which provides improved detection sensitivity and specificity. The assay involves the amplification of two specific and abundant target gene sequences in S. japonicum; a retrotransposon (SjR2) and a portion of a mitochondrial gene (nad1). The assay detected target sequences in different sources of schistosome DNA isolated from adult worms, schistosomules and eggs, and exhibits a high level of specificity, thereby representing an ideal tool for the detection of low levels of parasite DNA in different clinical samples including parasite cell free DNA in the host circulation and other bodily fluids. Moreover, being quantitative, the assay can be used to determine parasite infection intensity and, could provide an important tool for the detection of low intensity infections in low prevalence schistosomiasis-endemic areas. PMID:27021661

  12. Gene Transcription Profile in Mice Vaccinated with Ultraviolet-attenuated Cercariae of Schistosoma japonicum Reveals Molecules Contributing to Elevated IFN-γLevels

    Institute of Scientific and Technical Information of China (English)

    Xiang ZHU; Feng LIU; Chuan SU; Guan-Ling WU; Zhao-Song ZHANG; Min-Jun JI; Hai-Wei WU; Yong WANG; Xiao-Ping CAI; Lei ZHANG; Shu-Ying HU; Lin-Lin FU

    2005-01-01

    Vaccination with ultraviolet-attenuated cercariae of Schistosoma japonicum induced protective immunity against challenge infection in experimental animal models. Our preliminary study on the transcription levels of IFN-γ and IL-4 in splenic CD4+ T cells revealed that attenuated cercariae elicited predominantly a Thl response in mice at the early stage, whereas normal cercariae stimulated primarily Th2dependent responses. Further analysis on the gene profile of the skin-draining lymph nodes demonstrated that the levels of IFN-γ were significantly higher in vaccinated mice than those in infected mice at day 4, 7 and 14 post-vaccination or post-infection. However, for IL-12 and IL-4, the potent inducers of Th l and Th2 responses, respectively, as well as IL-10, there were no differences over the course of the experiment between the infected and vaccinated mice. To explore the underlying factors that may potentially contribute to elevated IFN-γ in vaccinated mice, the mRNA profiles of the skin-draining lymph nodes at day 4 postexposure were compared using oligonucleotide microarrays. Within the 847 probe sets with increased signal values, we focused on chemokines, cytokines and relevant receptors, which were validated by semi-quantitative RT-PCR. A comprehensive understanding of the immune mechanisms of attenuated cercariae-induced protection may contribute to developing efficient vaccination strategies against S. japonicum, especially during the early stage of infection.

  13. Oral delivery of the Sj23LHD-GST antigen by Salmonella typhimurium type III secretion system protects against Schistosoma japonicum infection in mice.

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    Guo Chen

    2011-09-01

    Full Text Available BACKGROUND: Schistosomiasis japonica is a zoonotic parasitic disease and oral vaccine delivery system would be benefit for prevention of this disease. Although attenuated salmonella has been used as an antigen expression vector for oral vaccine development, the membrane-bound vacuoles in which bacteria reside hinders the presentation of expressed heterologous antigens to the major histocompatibility complex (MHC molecules. The present work used an attenuated Salmonella typhimurium strain VNP20009 to secretory expression of Sj23LHDGST bivalent antigen from Schistosoma japonicum and tested the protective efficacy against S. japonicum infection in orally immunized mice. METHODOLOGY/PRINCIPAL FINDINGS: Promoters (nirB or pagC were used to express the antigen (Sj23LHDGST and the Salmonella type III or α-hemolysin secretion system was employed to secrete it. The immunoblotting analysis and fluorescent microscopy revealed that the antigen was effectively expressed and delivered to the cytosol of macrophages in vitro. Among recombinant vaccine strains, an engineered VNP20009 which expressed the antigen by nirB promoter and secreted it through type III secretion system (nirB-sopE(1-104-Sj23LHD-GST efficiently protected against S. japonicum infection in a mouse model. This strain elicited a predominantly IgG(2a antibody response and a markedly increase in the production of IL-12 and IFN-γ. The flow cytometric analysis demonstrated that this strain caused T cell activation as evidenced by significantly increased expression of CD44 and CD69. CONCLUSION/SIGNIFICANCE: Oral delivery of antigen by nirB-driven Salmonella typhimurium type III secretion system is a novel, safe, inexpensive, efficient and convenient approach for schistosome vaccine development.

  14. Schistosoma japonicum-infected hamsters (Mesocricetus auratus) used as a model in experimental chemotherapy with praziquantel, artemether, and OZ compounds.

    Science.gov (United States)

    Xiao, Shu-hua; Mei, Jing-yan; Jiao, Pei-ying

    2011-02-01

    The purpose of the study is to better understand the antischistosomal properties of artemether, praziquantel, and ozonide (OZ) compounds (synthetic trioxolanes, secondary ozonides) in hamster (Mesocricetus auratus) model. A total of 230 male hamsters infected each with 100 Schistosoma japonicum cercariae were used in the study. Groups of five to ten hamsters were treated orally with artemether, praziquantel, and OZ78 or OZ277 7-35 days post-infection at single doses of 50, 100, 150, or 200 mg/kg. Untreated but infected hamsters in each batch of test served as the control. All treated hamsters were sacrificed 4 weeks post-treatment for collection of residual worms using perfusion technique. Nonparametric method (Mann-Whitney test) was used to analyze the data. In groups of five hamsters treated with artemether 7, 14, 21, 28, and 35 days post-infection at single doses of 150 and 200 mg/kg, the difference of mean worm burden between each treated group and control group was statistically significant (P0.05). Further test with various single doses of 50-200 mg/kg confirmed the similar susceptibility of 7-day-old juvenile and 35-day-old adult schistosomes to artemether. After administration of praziquantel 100 mg/kg to groups of five hamsters 7, 21, and 35 days post-infection, higher worm burden reduction of 95.5% was seen in the group with 35-day-old adult schistosomes while in the groups with 7- and 21-day-old juvenile schistosomes, poor efficacy was seen with mean worm burden reductions of 36.6% and 35.6%. In the same batch of hamster treated with praziquantel 200 mg/kg, the moderate effect of the drug against 7- and 21-day-old worms was seen, but their mean worm burden was significantly higher than that of the group with adult schistosomes. In comparison of artemether and praziquantel against various stages of schistosomes, the results further demonstrated that artemether possessed similar effect against juvenile and adult schistosomes in hamsters, while praziquantel

  15. Combined IL-12 Plasmid and Recombinant SjGST Enhance the Protective and Anti-pathology Effect of SjGST DNA Vaccine Against Schistosoma japonicum.

    Science.gov (United States)

    Cheng, Po-Ching; Lin, Ching-Nan; Peng, Shih-Yi; Kang, Tsung-Fu; Lee, Kin-Mu

    2016-02-01

    Schistosomiasis is listed as one of most important tropical diseases and more than 200 million people are estimated to be infected. Development of a vaccine is thought to be the most effective way to control this disease. Recombinant 26-kDa glutathione S-transferase (rSjGST) has previously been reported to achieve a worm reduction rate of 42-44%. To improve the efficiency of the vaccine against Schistosoma japonicum, we immunized mice with a combination of pcDNA vector-encoded 26-kDa SjGST (pcDNA/SjGST), IL-12 expressing-plasmid (pIL-12), and rSjGST. Co-vaccination with pcDNA/SjGST, pIL-12, and rSjGST led to a reduction in worm burden, hepatic egg burden, and the size of liver tissue granulomas than that in the untreated infection controls. In addition, we detected high levels of specific IgG, IgG1, and IgG2a against the rSjGST antigen in infected mice vaccinated with this combination of pcDNA/SjGST, pIL-12, and rSjGST. Moreover, high expression levels of Th2 cytokines, including IL-4 and IL-10, were also detected in this group, without diminished levels of IL-12, INF-γ, and TNF-α cytokines that are related to parasite killing. In conclusion, we have developed a new vaccination regimen against S. japonicum infection and shown that co-immunization with pcDNA/SjGST vaccine, pIL-12, and rSjGST has significant anti-parasite, anti-hepatic egg and anti-pathology effects in mice. The efficacy of this vaccination method should be further validated in large animals such as water buffalo. This method may help to reduce the transmission of zoonotic schistosomiasis japonica. PMID:26891172

  16. Activation-Induced T Helper Cell Death Contributes to Th1/Th2 Polarization following Murine Schistosoma japonicum Infection

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    Xinyu Xu

    2010-01-01

    Full Text Available In chronic infectious diseases, such as schistosomiasis, pathogen growth and immunopathology are affected by the induction of a proper balanced Th1/Th2 response to the pathogen and by antigen-triggered activation-induced T cell death. Here, by using S. japonicum infection or schistosome antigens-immunized mouse model, or antigens in vitro stimulation, we report that during the early stage of S. japonicum infection, nonegg antigens trigger Th2 cell apoptosis via the granzyme B signal pathway, contributing to Th1 polarization, which is thought to be associated with worm clearance and severe schistosomiasis. Meanwhile, after the adult worms lay their eggs, the egg antigens trigger Th1 cell apoptosis via the caspase pathway, contributing to Th2 polarization, which is associated with mild pathology and enhanced survival of both worms and their hosts. Thus, our study suggests that S. japonicum antigen-induced Th1 and Th2 cell apoptosis involves the Th1/Th2 shift and favorites both hosts and parasites.

  17. Schistosoma japonicum risk in Jiangsu province, People’s Republic of China: identification of a spatio-temporal risk pattern along the Yangtze River

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    Kun Yang

    2013-11-01

    Full Text Available The risk for Schistosoma japonicum infection in Jiangsu province, People’s Republic of China, was investigated by a mouse bioassay. Various investigations were conducted in the period 2009-2011 with the presentation here representing the summary of the results from 45-50 sites in the marshlands along the Yangtze River’s course through the province. Indices representing three aspects of the infection were collected to assess risk: (i the proportion of sentinel points where at least one mouse infection was recorded; (ii the proportion of infected mice at each of these sites; and (iii the average worm burdens. Directional distribution analysis and scan statistics were used to explore the spatio-temporal risk pattern. The spatial distribution was oriented along the Yangtze River and the directional distributions for the proportion of infected mice and mean worm burdens were similar for the positive sentinel sites. Four statistically significant clusters were detected in 2009, but only one in 2010 and 2011, respectively. Temporal windows for infection risk were seen in June and September. The study illustrates the utility of spatio-temporal analysis in assessing the risk for schistosomiasis. This approach should be useful with respect to surveillance and response that can be expected to be increasingly applied when moving from morbidity control to transmission control.

  18. In vitro effect of the lethal antibody on schistosomula in sera of rhesus monkeys immunized with highly x-irradiated cercariae. [Schistosoma mansoni, S. japonicum

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    Li Hs' u, S.Y.; Hs' u, H.F.; Isacson, P.; Kremenak, B.W.; Cheng, H.F.

    1976-12-01

    The in vitro effect of the lethal antibody on schistosomula in sera of rhesus monkeys immunized with highly x-irradiated cercariae of Schistosoma mansoni or S. japonicum was studied. In all 6 experimental monkeys, 4 unchallenged and 2 challenged, the effects of lethal antibody on schistosomula were demonstrated. The sera of the challenged monkeys had no stronger lethal effect than those of the unchallenged monkeys. This shows that the lethal antibody can be produced by the antigenic stimulation of schistosomula alone. The mortality rates of schistosomula in immune sera were already high at day 1, increased to a certain extent from day 1 to day 4, but showed no significant further increase in days 5 and 6. Two kinds of immunological reactions were observed: perischistosomular precipitate (PSP) and perischistosomular envelope (PSE). Schistosomula surrounded with PSP were usually dying or dead and those enclosed in PSE were usually alive and motile. Thus PSP may be related with the lethal antibody and PSE with a kind of enhancing antibody. Schistosomula with PSP showed a positive fluorescent reaction when stained with fluorescein-labeled rabbit anti-rhesus IgG. Scanning electron micrographs of schistosomula with PSP showed a highly degenerated tegument. These facts indicate that the antibody in PSP contains a fraction of IgG which acts on the tegument of schistosomula.

  19. Mini-review: the ultrasonographical and serological chanbges and their improvement after praziquantel treatment Schistosoma japonicum infected patients in Leyete, Philippines

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    Manami Tanaka

    1992-01-01

    Full Text Available We have identified the specific ultrasonographical (US changes in Schistosoma japonicum infected patients with the serological changes in general liver function markers. The US examination with the following haematological and biochemical serum analysis was performed on 102 patients in Shistosomiasis Hospital, Leyte, Philippines. The US liver images were classified into 4 patterns according to the development of periportal fibrosis and the patterns of echogenic bands. Among various haematological and biochemical serum parameters of liver damage. The serum levels of total bile acid (TBA and procollagen-III-peptide (P-III-P correlated well with the development of hepatic fibrosis and the portal hypertension. These patients were subsequently treated with praziquantel (3 x 20 mg/kg, and improvement of the thickening of the portal vein wall and the dintensity of the echogenic band formation was detected 6 months after treatment. The significant US changes could not be detected in the patients with severe hepatic fibrosis caused in the long term infection. The results revealed that the US examination with the serum TBa level would provider a sensitive tool monitor the severity of the infection and also the improvement occured shortly after praziquantel treatment.

  20. Generation of a Novel Bacteriophage Library Displaying scFv Antibody Fragments from the Natural Buffalo Host to Identify Antigens from Adult Schistosoma japonicum for Diagnostic Development.

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    Christopher G Hosking

    2015-12-01

    Full Text Available The development of effective diagnostic tools will be essential in the continuing fight to reduce schistosome infection; however, the diagnostic tests available to date are generally laborious and difficult to implement in current parasite control strategies. We generated a series of single-chain antibody Fv domain (scFv phage display libraries from the portal lymph node of field exposed water buffaloes, Bubalus bubalis, 11-12 days post challenge with Schistosoma japonicum cercariae. The selected scFv-phages showed clear enrichment towards adult schistosomes and excretory-secretory (ES proteins by immunofluorescence, ELISA and western blot analysis. The enriched libraries were used to probe a schistosome specific protein microarray resulting in the recognition of a number of proteins, five of which were specific to schistosomes, with RNA expression predominantly in the adult life-stage based on interrogation of schistosome expressed sequence tags (EST. As the libraries were enriched by panning against ES products, these antigens may be excreted or secreted into the host vasculature and hence may make good targets for a diagnostic assay. Further selection of the scFv library against infected mouse sera identified five soluble scFv clones that could selectively recognise soluble whole adult preparations (SWAP relative to an irrelevant protein control (ovalbumin. Furthermore, two of the identified scFv clones also selectively recognised SWAP proteins when spiked into naïve mouse sera. These host B-cell derived scFvs that specifically bind to schistosome protein preparations will be valuable reagents for further development of a cost effective point-of-care diagnostic test.

  1. Generation of a Novel Bacteriophage Library Displaying scFv Antibody Fragments from the Natural Buffalo Host to Identify Antigens from Adult Schistosoma japonicum for Diagnostic Development.

    Science.gov (United States)

    Hosking, Christopher G; McWilliam, Hamish E G; Driguez, Patrick; Piedrafita, David; Li, Yuesheng; McManus, Donald P; Ilag, Leodevico L; Meeusen, Els N T; Veer, Michael J de

    2015-12-01

    The development of effective diagnostic tools will be essential in the continuing fight to reduce schistosome infection; however, the diagnostic tests available to date are generally laborious and difficult to implement in current parasite control strategies. We generated a series of single-chain antibody Fv domain (scFv) phage display libraries from the portal lymph node of field exposed water buffaloes, Bubalus bubalis, 11-12 days post challenge with Schistosoma japonicum cercariae. The selected scFv-phages showed clear enrichment towards adult schistosomes and excretory-secretory (ES) proteins by immunofluorescence, ELISA and western blot analysis. The enriched libraries were used to probe a schistosome specific protein microarray resulting in the recognition of a number of proteins, five of which were specific to schistosomes, with RNA expression predominantly in the adult life-stage based on interrogation of schistosome expressed sequence tags (EST). As the libraries were enriched by panning against ES products, these antigens may be excreted or secreted into the host vasculature and hence may make good targets for a diagnostic assay. Further selection of the scFv library against infected mouse sera identified five soluble scFv clones that could selectively recognise soluble whole adult preparations (SWAP) relative to an irrelevant protein control (ovalbumin). Furthermore, two of the identified scFv clones also selectively recognised SWAP proteins when spiked into naïve mouse sera. These host B-cell derived scFvs that specifically bind to schistosome protein preparations will be valuable reagents for further development of a cost effective point-of-care diagnostic test. PMID:26684756

  2. 1991~2010年江苏省世业镇牛血吸虫感染情况调查%SURVEY ON BOVINE SCHISTOSOMA JAPONICUM INFECTION IN SHIYE TOWN OF JIANGSU PROVINCE FROM 1991 TO 2010

    Institute of Scientific and Technical Information of China (English)

    任雪枫; 高升; 包新奇; 李玉玲; 石锦良; 祝培波; 杨伟华

    2011-01-01

    本文报告了江苏省镇江市丹徒区世业镇1991~2010年牛血吸虫感染情况。世业镇牛血吸虫感染率在不断反复中逐渐降低,到2006年下降至0。在1994~1998年和2002~2005年出现不同程度的反弹,经分析与江水水位变化有密切的关系。观测结果说明江苏省取得了显著血防效果,但血吸虫病防控仍是一项长期任务。%The article reported bovine Schistosoma japonicum infection in Shiye town of Jiangsu Province from 1991 to 2010.The infection rate decreased progressively from 43.36% in 1991 to 0% in 2006.There were two rebounds of infection rate 1994-1998 and 2002-2005,which was largely related to the change of the water level of Changkiang river.The observed results showed that Jiangsu Province had made an outstanding progress in the control of schistosomaiasis,but it had been a long-term task to prevent Schistosoma japonicum infection.

  3. Comparative Study on the Immunogenicity between Recombinant MS-Sj26GST Vaccine and Recombinant BCG-Sj26GST Vaccine in Schistosoma japonicum

    Institute of Scientific and Technical Information of China (English)

    戴五星; 高红; 黄海浪; 袁野; 胡佳杰; 皇甫永穆

    2003-01-01

    The BALB/c mice were immunized with rMS-Sj26GST and rBCG-Sj26GST vaccine inSchistosoma japonicum by subcutaneous injection. After they were immunized for 8 weeks, the eye-balls were removed to get blood and macrophages of abdominal cavity and spleen cells were harves-ted. The lymphocytic stimulating index (SI) was used to measure the cellular proliferating abilityand NO release was used to measure the phagocytic activity of the macrophages. By using ELISAkit, the levels of interleukin-2 (IL-2) and interferon-γ(IFN-γ) in serum and the splenic lymphocyt-ic cultured supernatant were detected. The results showed that after the mice were immunized with106 CFU of rMS-Sj26GST and rBCG-Sj26GST vaccine separately by subcutaneous injection, prolif-erating ability of splenic lymphocytes in the mice showed no difference (P>0.05), but both weresignificantly increased as compared with that in the control group(P<0.05); The contents of NOin the intraperitoneal macrophages of rMS-Sj26GST vaccine group were significantly lower than inthe control group (P<0. 001) and rBCG-Sj26GST vaccine group (P<0. 01); The levels of serumIL-2 in the rMS-Sj26GST vaccine group were significantly increased as compared with that in thecontrol group (P<0. 001), vector group (P<0.01) and rBCG-Sj26GST vaccine group (P<0.05);The contents of serum IFN-γ in the rMS-Sj26GST vaccine group were significantly increased ascompared with that in the control group (P<0.01) and rBCG-Sj26GST vaccine group (P<0.05).The contents of IFN-γ in the cultured supernatant were significantly lower than those of rBCG-Sj26GST vaccine group (P<0. 001), but were significantly increased as compared with that in thecontrol group (P<0.01). It was indicated that both vaccines could enhance the immune response ofthe mice, but rMS-Sj26GST vaccine had stronger immunogenicity than rBCG-Sj26GST vaccine.

  4. Reduction of Total Antioxidant Capacity in Artemether-treated Female Schistosoma japonicum%蒿甲醚诱导日本血吸虫雌虫总抗氧化能力下降

    Institute of Scientific and Technical Information of China (English)

    翟自立; 梅静艳; 焦佩英; 肖树华

    2002-01-01

    目的观察蒿甲醚对日本血吸虫成虫总抗氧化能力的影响.方法体外将血吸虫在含蒿甲醚和氯化血红素的培养液内培养24 h后,或体内感染小鼠经蒿甲醚300 mg/kg治疗6~24 h后,测定虫体的总抗氧化能力.结果体外50μmol/L的蒿甲醚与氯化血红素伍用引起雌虫总抗氧化能力明显下降.体内蒿甲醚作用血吸虫6 h,即见雌虫的总抗氧化能力明显下降.体内、体外试验中,蒿甲醚对雄虫的总抗氧化能力均无影响.结论蒿甲醚诱导雌虫总抗氧化能力下降.%Objective To study the effect of artemether (Art) on total antioxidant capacity (T-AOC) in adult Schistosoma japonicum. Methods In vitro, the T-AOC was determined in five-week old worms incubated without or with Art and/or hemin for 24 h, and the worms were continuously incubated for 96 h, then worm survival was assessed. In vivo, T-AOC was determined in worms freshly recovered from mice 6 - 24 h after treatment with Art 300 mg/kg. Results Throughout 96 h incubation no worms were killed by 50 μmol/L Art or 50 μmol/L hemin alone, but approximatdy 80% of them were killed by Art plus hemin. Addition of reduced glutathione and vitamin E could significantly block the cidal action of the combined treatment. No effect on T-AOC was seen in the worms exposed to Art or heroin alone for 24 h, but the combined treatment led to a pronounced T-AOC reduction in female worms in vitro. Such a drug effect on female worms was demonstrated in vivo. After female worms were exposed to Art for 6 - 24 h in vivo, their T-AOC was significantly reduced by 40% - 64%. However, no drug effect on male worms' T-AOC was observed in vivo and in vitro exposed to Art plus hemin. Conclusion Art-induced T-AOC reduction in female worms may sensitize them to lethal damages of endogenous and exogenous oxygen radicals.

  5. Microarray Analysis of Gene Expression Profiles of Schistosoma japonicum Derived from Less-Susceptible Host Water Buffalo and Susceptible Host Goat

    OpenAIRE

    Jianmei Yang; Yang Hong; Chunxiu Yuan; Zhiqiang Fu; Yaojun Shi; Min Zhang; Liuhong Shen; Yanhui Han; Chuangang Zhu; Hao Li; Ke Lu; Jinming Liu; Xingang Feng; Jiaojiao Lin

    2013-01-01

    BACKGROUND: Water buffalo and goats are natural hosts for S. japonicum in endemic areas of China. The susceptibility of these two hosts to schistosome infection is different, as water buffalo are less conducive to S. japonicum growth and development. To identify genes that may affect schistosome development and survival, we compared gene expression profiles of schistosomes derived from these two natural hosts using high-throughput microarray technology. RESULTS: The worm recovery rate was low...

  6. 水牛和猪感染日本血吸虫后的自愈现象及其机制%The self-cure phenomenon in buffalo and pig infected with Schistosoma japonicum and its mechanism

    Institute of Scientific and Technical Information of China (English)

    吕美云; 李宜锋; 林丹丹

    2010-01-01

    动物感染血吸虫后的自愈现象是指动物在感染血吸虫一段时间后虫负荷数急剧下降、虫体自然清除的现象.水牛和猪作为主要的血吸虫病传染源,在血吸虫病流行传播中起到重要作用.已有研究表明,水牛和猪感染日本血吸虫后有自愈现象,阐明其发生机制对于防治血吸虫病和研制血吸虫疫苗均有重要意义.该文主要围绕水牛、猪感染日本血吸虫后产生的与自愈有关的实验和现场研究作一综述,并对其发生的机制进行探讨.%Self-cure refers to the phenomenon that the number of worms declines sharply and parasites are cleared up naturally after animals infected with Schistosoma japonicum for some time. Buffaloes and pigs play an important role in schistosomiasis transmission as the main sources of infection. Some studies have shown that self-cure occurs in water buffaloes and pigs infected with S. japonicum. It has great significance to clarify the mechanisms behind the phenomenon of self-cure for prevention and control of schistosomiasis and development of anti-schistosomiasis vaccine. This paper summarized the experimental research and field epidemiologi-cal studies around self-cure in water buffaloes and pigs infected with 5. japonicum and discussed the mechanisms of self-cure.

  7. Molecular characterization of thyroid hormone receptor beta from Schistosoma japonicum and assessment of its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Qiu Chunhui

    2012-08-01

    Full Text Available Abstract Background Thyroid hormones (TH modulate growth, development and differentiation and metabolic processes by interacting with thyroid hormone receptors (THRs. The purpose of this study was to identify a novel thyroid hormone receptor beta encoding gene of Schistosoma japonicum (SjTHRβ and to investigate its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice. Methods The full-length cDNA sequence of SjTHRβ, its gene organization, and its transcript levels were characterized, and the phylogenetic relationship between THR, RAR and RXR from other organisms were analysis, the ability of this protein binding to a conserved DNA core motif, and its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice were evaluated. Results The SjTHRβ cDNA was cloned, verified by 5’ and 3’ Rapid Amplification of cDNA Ends and shown to be polyadenylated at the 3’end, suggesting the transcript is full-length. SjTHRβ is homologous to THRs from other species and has a predicted conservative DNA binding domain and ligand binding domain that normally characterizes these receptors. A comparative quantitative PCR analysis showed that SjTHRβ was the highest expressed in 21d worms and the lowest in 7 d and 13 d schistosomula. The cDNA corresponding to DNA binding domain (SjTHRβ-DBD and ligand binding domain (SjTHRβ-LBD were cloned and subsequently expressed in E coli. The expressed proteins were used to immunize mice and generate specific serum against recombinant SjTHRβ (rSjTHRβ. Western blotting revealed that anti-rSjTHRβ-LBD serum recognized two protein bands in extracts from 21 d worm with molecular sizes of approximately 95 kDa and 72 kDa. Electrophoretic mobility shift assay (EMSA analysis showed that rSjTHRβ-DBD could bind to a conserved DNA core motif. Immunization of BALB/c mice with rSjTHRβ-LBD could induce partial protective efficacy(27.52% worm reduction and 29.50% liver eggs

  8. Phenotype of dendritic cell loaded with antigens from Schistosoma japonicum%日本血吸虫抗原负载树突状细胞的表型研究

    Institute of Scientific and Technical Information of China (English)

    李小红; 曹建平; 汤林华; 周何军

    2010-01-01

    Objective To investigate the phenotype of dendritic cell( DC) loaded with GST and SEA from Schistosoma japonicum. Methods Bone marrow cells were cultured in the presence of IL-4 and GM-CSF to induce dendritic cells(DCs). These DCs were stimulated by purified GST and SEA antigen from Schistosoma japonicum, respectively. FITC labeled anti-GST monoclonal antibody was used to detect the loading of antigen. After that, the expression of CD40, CD80, CD86 and CD11c on the membrane of DC were analyzed by fluorescence activated cell sorting(FACS). Results The loading of antigen was confirmed by the detection of GST on the cells. GST was successfully loaded on DCs. The positive rates of CD40, CD80 and CD86 in the groups stimulated with GST or SEA were not raised significantly, comparing to the PBS control. Conclusion DC loaded with GST and SEA antigen from Schistosoma japonicum exhibited an immature phenotype.%目的 研究负载日本血吸虫谷胱甘肽S-转移酶(glutathione S-transferase,GST)和可溶性虫卵抗原(soluble egg antigen,SEA)的树突状细胞的表型. 方法 骨髓来源的细胞经白介素-4(interleukin-4,IL-4)、粒细胞-巨噬细胞集落刺激因子(granulocyte-macrophage colony stimulating factor,GM-CSF)诱导培养,获得树突状细胞,体外经GSI、SEA抗原刺激.用异硫氰酸荧光素(fluorescein isothiocyanate,FITC)标记的抗GST单克隆抗体染色法检测GST的负载情况.流式细胞仪检测血吸虫抗原负载后树突状细胞表面CD40、CD80、CD86、CD11c分子的表达情况,并与脂多糖(lipopolysaccharide,LPS)、PBS刺激组作比较. 结果 GST负载后在荧光显微镜下可观察到抗GST的特异荧光,表明抗原已被细胞摄取.与LPS相比较,GST、SEA抗原负载后,树突状细胞表面分子CD40、CD86上调不显著,而更类似于PBS刺激组. 结论 日本血吸虫抗原负载后,树突状细胞的表型类似于未成熟表型.

  9. Microarray analysis of gene expression profiles of Schistosoma japonicum derived from less-susceptible host water buffalo and susceptible host goat.

    Directory of Open Access Journals (Sweden)

    Jianmei Yang

    Full Text Available BACKGROUND: Water buffalo and goats are natural hosts for S. japonicum in endemic areas of China. The susceptibility of these two hosts to schistosome infection is different, as water buffalo are less conducive to S. japonicum growth and development. To identify genes that may affect schistosome development and survival, we compared gene expression profiles of schistosomes derived from these two natural hosts using high-throughput microarray technology. RESULTS: The worm recovery rate was lower and the length and width of worms from water buffalo were smaller compared to those from goats following S. japonicum infection for 7 weeks. Besides obvious morphological difference between the schistosomes derived from the two hosts, differences were also observed by scanning and transmission electron microscopy. Microarray analysis showed differentially expressed gene patterns for parasites from the two hosts, which revealed that genes related to lipid and nucleotide metabolism, as well as protein folding, sorting, and degradation were upregulated, while others associated with signal transduction, endocrine function, development, immune function, endocytosis, and amino acid/carbohydrate/glycan metabolism were downregulated in schistosomes from water buffalo. KEGG pathway analysis deduced that the differentially expressed genes mainly involved lipid metabolism, the MAPK and ErbB signaling pathways, progesterone-mediated oocyte maturation, dorso-ventral axis formation, reproduction, and endocytosis, etc. CONCLUSION: The microarray gene analysis in schistosomes derived from water buffalo and goats provide a useful platform to disclose differences determining S. japonicum host compatibility to better understand the interplay between natural hosts and parasites, and identify schistosome target genes associated with susceptibility to screen vaccine candidates.

  10. 日本血吸虫反式剪接前导RNA的鉴定%Identification and Characterization of an mRNA Trans-splicing Leader in Schistosoma Japonicum

    Institute of Scientific and Technical Information of China (English)

    李锐; 贺亮; 郝力力

    2012-01-01

    RNA trans-splicing occurs in a wide range of eukaryotes, from protozoa to chordates. To investigate the SL RNA-mediated trans-splicing in the zoonotic trematode Schistosoma japonicum, a spliced-leader (SL) RNA was cloned in adults using race. The 36-nucleotide SL in S. Japonicum was derived from a 90-nucleotide nonpolyadenylylated RNA transcript encoded by 55 copies of SL genes dispersed in the genome confirmed by blot and real time PCR. Differential transcription patterns of the SL gene in the parasite developmental stages were observed using real time PCR. Predominant expression of SL RNA was found in the two developmental stages, egg and cercariae. Expression of SL RNA transcripts in female was the least. No significant expression difference between male and schistosomulum (3 d and 14 d) was observed. In summary, trans-splicing of spliced leader might acted as an important mechanism of post-transcriptional gene regulation in S. Japonicum.%RNA反式剪接现象广泛存在于真核生物中,包括单细胞原虫以及低等脊索动物.为鉴定日本血吸虫中是否存在SL RNA介导的反式剪接,运用Race方法从成虫中克隆出了1个90 nt的SL RNA基因,36 nt的RNA前导序列正是来源于此90 nt的无PolyA结构的SL RNA,并通过Northern进一步证实了该基因的存在.同时采用荧光定量和Southern对其拷贝数、基因组上的分布方式以及虫体不同阶段的表达量进行了鉴定,发现SL RNA具有55个拷贝并在基因组上呈散在分布;在虫卵和尾蚴时期SL RNA基因的转录丰度最高,雌虫阶段最低,雄虫、3天童虫以及14天童虫阶段无明显差别.结果表明,SL RNA介导的反式剪接可能是日本血吸虫基因转录后重要的调控机制之一.

  11. Fluorescent quantitative real-time PCR for quantitative detection of Schistosoma japonicum cercariae in water%荧光实时定量PCR定量水体中日本血吸虫尾蚴方法的建立

    Institute of Scientific and Technical Information of China (English)

    王本敬; 王文波; 周霞; 陈艳勤; 张静; 刘晨晨; 梁幼生; 诸葛洪祥

    2011-01-01

    目的 建立快速、高效、特异的定量水体中尾蚴的数量和检测水体中日本血吸虫尾蚴残余基因组DNA的方法,来评估水体受日本血吸虫尾蚴污染的程度.方法 根据日本血吸虫基因组DNA中的3个多拷贝序列Sjrh1.0(序列号:U92488.1)、18S小亚基单位核楷体核酸基因(18SrRNA)序列(序列号:AY157226.1)和逆转录转座子SjR2的G55A序列(G55A)(序列号:AF412221.1),设计常规PCR引物和实时定量PCR引物,选取较好的靶序列建立SYBR GreenI实时定量PCR方法,绘制尾蚴数的对数与Ct值的标准曲线,并对疫水中日本血吸虫尾蚴残余的基因组DNA进行检测.结果 尾蚴数的对数与Ct值的标准曲线有良好的线性关系,相关系数r2为0.918 6,重复性良好.结论 本方法特异性高,灵敏,可定量水体中尾蚴数,对疫水检测有一定的预警作用.%The objective was to establish a rapid, sensitive and specific method to detect the number of cercariea in water and evaluate level of water stained by Schistosoma japonicum cercariea. Convenience PCR primer sequences were designed tar-geting pSjrH1.0(U92488. 1), Sjl8SrRNA( AY157226. 1) and the clone G55A of the highly repetitive retrotransposon SjR2 (AF412221. 1) in S. japonicum genome, and sequence the PCR product. Based on conserved sequence of pSjrHl. 0, Sjl8SrRNA and clone G55A of highly repetitive retrotransposon SjR2 (G55A), design primers and the quantitative real-time PCR essays were established, by which, the amplifying products were 150 to 170 bp. The sequence in S. japonicum genome and the best annealing temperature were selected by comparing their threshold cycle (Ct value). Then the quantitative real-time PCR essays were established under the better annealing temperature, generate standard curve between the logarithms of gradi-ent diluted DNA templates and Ct value. Five DNA samples extracted from 1, 5, 10, 20 and 80 cercariae were used as quanti-tative template to generate standard curve

  12. 日本血吸虫原肌球蛋白cDNA的克隆及其在大肠杆菌中表达%Cloning of cDNA encoding Schistosoma japonicum tropomyosin and its expression in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    曹建平; 刘述先; 宋光承; 徐馀信

    2002-01-01

    Objective To perform cloning of the gene encod ing Chinese Schistosoma japonicum tropomyosin (SjcTM) and its expression in Escherichia coli.Methods SjcTM cDNA fragment, except for 14 amino acids at the amino terminus, was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) with total RNA extracted from adult worms of S. Japonicum . The RT-PCR product was cloned into T vector and sequenced. The SjcTM cDNA, derived from the constructed TA clone pGEM-SjcTM, was then subcloned into the expressing vector pBV220. After characterization by agarose gel electrophoresis, endonucleases digestion and PCR, the resultant recombinant plasmid was used for expression under the temperature-dependent condition. Results The RT-PCR product, cloned into a Tvector, was sequenced and shown to be 96.5% identical at the nuclei acid level and 98.1 % identical in deduced amino acid sequence to that of S. Mansoni tropomyosi n. The target DNA fragment was then subcloned into a prokaryotic vector pBV220 . Induced expression in E. Coli DH5α cells resulted in a constant level of recombinant protein production. The results of SDS-PAGE and Western blot rev ealed that the molecular weight of non-fusion recombinant protein (rSjcTM) was approximately 32 kDa and could be recognized specifically by a polyclonal antise rum specific for native S. Japonicum tropomyosin (SjcTM). Conclusion The engineering of the cDNA encodingS. Japonicum tropomyosin and its bacterial expression was successfully made.%目的克隆日本血吸虫原肌球蛋白编码基因,并在大肠杆菌中表达.方法抽提日本血吸虫(大陆株)成虫总RNA,经逆转录-聚合酶链反应(RT-PCR)获得编码日本血吸虫原肌球蛋白的cDNA片段,该片段与全序列比较,缺氨基端14个氨基酸.该PCR产物克隆入T 载体并对插入片段进行序列测定后,亚克隆入表达载体pbV220,经琼脂糖凝胶电泳、限制性酶切反应和PCR鉴定后,选择克隆用于温控表达.结果 RT-PCR产物

  13. Characterization of a gene family encoding SEA (sea-urchin sperm protein, enterokinase and agrin-domain proteins with lectin-like and heme-binding properties from Schistosoma japonicum.

    Directory of Open Access Journals (Sweden)

    Evaristus Chibunna Mbanefo

    Full Text Available BACKGROUND: We previously identified a novel gene family dispersed in the genome of Schistosoma japonicum by retrotransposon-mediated gene duplication mechanism. Although many transcripts were identified, no homolog was readily identifiable from sequence information. METHODOLOGY/PRINCIPAL FINDINGS: Here, we utilized structural homology modeling and biochemical methods to identify remote homologs, and characterized the gene products as SEA (sea-urchin sperm protein, enterokinase and agrin-domain containing proteins. A common extracellular domain in this family was structurally similar to SEA-domain. SEA-domain is primarily a structural domain, known to assist or regulate binding to glycans. Recombinant proteins from three members of this gene family specifically interacted with glycosaminoglycans with high affinity, with potential implication in ligand acquisition and immune evasion. Similar approach was used to identify a heme-binding site on the SEA-domain. The heme-binding mode showed heme molecule inserted into a hydrophobic pocket, with heme iron putatively coordinated to two histidine axial ligands. Heme-binding properties were confirmed using biochemical assays and UV-visible absorption spectroscopy, which showed high affinity heme-binding (K D = 1.605×10(-6 M and cognate spectroscopic attributes of hexa-coordinated heme iron. The native proteins were oligomers, antigenic, and are localized on adult worm teguments and gastrodermis; major host-parasite interfaces and site for heme detoxification and acquisition. CONCLUSIONS: The results suggest potential role, at least in the nucleation step of heme crystallization (hemozoin formation, and as receptors for heme uptake. Survival strategies exploited by parasites, including heme homeostasis mechanism in hemoparasites, are paramount for successful parasitism. Thus, assessing prospects for application in disease intervention is warranted.

  14. Ageing Down-modulates the Immune Responses to Schistosoma japonicum Infection in Mice%衰老下调小鼠对日本血吸虫感染的免疫应答

    Institute of Scientific and Technical Information of China (English)

    杨云帆; 李雍龙; 孙谦; 苏斌涛; 林琳; 李曼君; 陈琳; 徐宏; 雷家慧; 刘文琪

    2011-01-01

    目的 研究衰老对小鼠感染日本血吸虫后免疫应答的影响.方法 幼龄(2月龄)和老龄(18月龄)雌性BALB/c小鼠各8只,每鼠感染日本血吸虫尾蚴(40±1)条.感染后6周剖杀小鼠,经门静脉灌注收集成虫,计数虫荷;KOH消化法收集肝脏中的虫卵,并计数.制作肝脏连续病理切片,测量两组小鼠肝脏增生期平均单卵肉芽肿的大小,计算单卵肉芽肿体积.常规法制备脾淋巴细胞悬液进行T淋巴细胞增殖实验,计算刺激指数(SI).ELISA法检测脾淋巴细胞中γ干扰素(IFN-γ)和白细胞介素4(IL-4)的表达水平.结果 幼龄组小鼠体内的虫荷和每克肝组织虫卵数分别为26.00±2.42和(2.08±0.87)×104,老龄组虫荷和每克肝脏虫卵数分别为19.75±1.95和(1.59±1.05)×104,两组间的差异有统计学意义(P<0.05).幼龄组肝脏单卵肉芽肿平均体积[(47.02±24.13)×10-3 mm3]明显大于老龄组[(30.13±10.97)×10-3 mm3](P<0.05).T淋巴细胞增殖实验结果 显示,老龄组脾淋巴细胞对ConA的增殖反应(SI:1.08±0.12)低于幼龄组(SI:1.31±0.14),其脾细胞培养上清中IFN-γ和IL-4的含量[(24.05±6.24)、(4.15±0.68) pg/ml]也明显低于幼龄组[(34.25±8.69)、(7.25±0.83) pg/ml] (P<0.05).结论 衰老引起小鼠对日本血吸虫感染的免疫应答下降,从而减轻了日本血吸虫感染引起的免疫病理损害.%Objective To investigate the effect of ageing on the immune responses against Schistosoma japonicum infection in mice. Methods Female BALB/c mice were divided into young group (2 months) and old group (18 months),each composed of 8 mice. Each mouse was percutaneously infected with 40±1 S. japonicum cercanae. At 6 weeks post-infection,the mice were sacrificed, and the spleens were removed and single-cell suspensions of splenocytes were prepared. Worms were perfused from hepatic portal system and counted. The number of eggs in the liver was determined after KOH digestion. Mean single-egg granulomas

  15. Effect of calcium cyanamid synthetic drug on Schistosoma japonicum egg morphology%氰氨化钙合成药物对血吸虫虫卵形态学影响

    Institute of Scientific and Technical Information of China (English)

    周义生; 彭国华; 胡主花; 冯小武; 朱蓉; 魏望远; 郭家钢

    2015-01-01

    目的:观察虫卵经氰氨化钙合成药物作用后的形态改变,为进一步研究氰氨化钙合成药物杀灭血吸虫虫卵作用机理提供依据。方法向含有血吸虫虫卵的阳性牛粪中加入氰氨化钙合成药物并搅拌,模拟野粪自然形态堆放于洲滩上;同时设空白对照。于1、2、3、7d后分别取样,收集血吸虫虫卵,于显微镜下观察虫卵形态。结果虫卵经氰氨化钙合成药物作用后,颜色逐步加深,毛蚴萎缩,卵壳变厚,3d后胚膜不完整,7d后毛蚴严重变形;对照组毛蚴未见明显萎缩。结论氰氨化钙合成药物对虫卵胚膜及毛蚴有损伤作用,且随时间延长而损伤加重。%Objective To study the morphological change of Schistosoma japonicum eggs processed by calcium cyanamide synthetic drug,so as to provide the basis for further study of the mechanism that calcium cyanamide synthetic drug to schisto⁃some eggs. Methods The calcium cyanamide synthetic drug was added to the cattle feces containing schistosome eggs and mixed up,and then the cattle feces was stacked as original shape on the marshland. Blank controls were set at the same time. The cattle feces samples were collected and the schistosome eggs were observed under a microscope on the 1st,2nd,3rd,7th day after the experiment. Results By the effect of calcium cyanamide synthetic drug,the color of eggs was deepening gradual⁃ly,the miracidia were atrophied,and the shells of eggs were thickened. The embryonic membrane of miracidia was no longer completed 3 days later,and the miracidia were deformed severely 7 days later. The atrophy of miracidia was not obvious in the blank controls. Conclusion The schistosome miracidia and embryonic membrane can be damaged by the calcium cyanamide synthetic drug,and worse damaged with time extending.

  16. Myeloradiculitis: a rare event in schistosoma infection.

    Science.gov (United States)

    Wichmann, D; Hofmann, C; Sudeck, H; Burchard, G-D; Moser, A

    2006-12-01

    Schistosomiasis a parasitic disease caused by trematodes is widely distributed in (sub-)tropical countries. Depending on the species the infection manifests clinically as gastrointestinal (preferentially Schistosoma mansoni and S. japonicum) or urinary (preferentially S. haematobium) disorders. Here we present an uncommon case of myeloradiculitis leading to bladder palsy and sensory loss at the lower limbs. PMID:17180592

  17. 日本血吸虫感染不同相容性动物宿主的比较研究%Comparative study on Schistosoma japonicum infection in different permissive animal hosts

    Institute of Scientific and Technical Information of China (English)

    杨健美; 林矫矫; 苑纯秀; 冯新港; 傅志强; 石耀军; 刘金明; 洪炀; 李浩; 陆珂

    2012-01-01

    The aim was to understand the difference for worm development , worm morphology and host's histopatholo-gy in Schistosoma j aponicum (S. j aponicum) infected animal hosts , including natural hosts and experimental animal hosts . We artificially infected six animal hosts (yellow cattle , water buffalo , goat, New Zealand rabbit , BALB/c mice , and Wistar rat) with the same source of S . japonicum cercariae . The parasites were perfused through the hepatic portal vein on day 49 after infection. The male and female worms were detached manually and counted , and the length and width of the worms were measured . The results showed that the worm recoveries in permissive hosts were higher than that in non permissive hosts , and the length of the worms from permissive hosts were greater than those from non permissive hosts . Parasites in all the hosts could develop into maturation and cause liver damage in their hosts except for Wistar rat . The livers from permissive hosts were fulfilled with white egg nodules , and composed of egg- granulomas ; while the livers from water buffalo were red but with few egg nodules ; the livers from Wistar rat had no damage at all . The histologies! sections from livers of infected natural hosts showed that in yellow cattle and goat , hepatocytes displayed mild swelling , and a large number of inflammatory cells were seen to be in -filtrating and aggregating , including eosinophils and lymphocytes , and typical striped eosinophilic deposits were observed . Compared with yellow cattle and goat , the structural integrity of the hepatic lobules in infected buffalo was intacted in the liv -ers . There was actinomorphous distribution of hepatic cord centered on central veins , polygonal hepatocytes without edema and inflammatory cell infiltration , leaving only scattered neutrophils and monocytes . This study provides reference data for labora- tory and field studies in understanding the differences of S. j aponicum infection in different

  18. 3种保虫宿主日本血吸虫特征性差异表达基因的筛选与验证%Screening and verification on characteristic differentially expressed genes of Schistosoma japonicum from three reservoir hosts

    Institute of Scientific and Technical Information of China (English)

    杨健美; 林矫矫; 石耀军; 冯新港; 傅志强; 苑纯秀; 刘金明; 洪炀; 李浩; 陆珂

    2012-01-01

    Objective To get the characteristic differentially expressed genes of Schistosoma japonicum from three important reservoir hosts: yellow cattle, water buffalo and goat, so as to find the genetic markers to identify the various sources of the parasite reservoir hosts. Methods The 49 d worms were collected from artificially infected animals, and the total RNA(s) of worms were extracted and reverse-transcripted to cDNA, and then hybridized with custom-built microarray to screen characteristic differentially expressed genes of every hosl, and the microarray results were validated by the real-time PCR method. Results From results of microarray, we got 3 characteristic differentially expressed genes of S. japonicum from yellow cattle, 4 from water buffalo and 7 from goat. We verified schistosome samples from three reservoir hosts in another experiment, the results showed that 2 in yellow cattle, 3 in water buffalo, and 5 in goat were verified to be consistent with microarray results. Conclusions The ten characteristic differentially expressed genes of S. japonicum from three reservoir hosts screened by microarray might be used as genetic markers to identify the various sources of reservoir hosts for S. japonicum.%目的 筛选日本血吸虫3种重要保虫宿主来源虫体的特征性差异表达基因,寻找可以用于鉴别这3种宿主来源虫体的遗传标记.方法 日本血吸虫尾蚴人工感染黄牛、水牛和山羊,收集感染后49 d成虫,分别抽提RNA,逆转录成cDNA,体外转录为cRNA并进行片段化;采用定制的血吸虫芯片分别进行杂交,筛选每种宿主来源虫体的特征性差异表达基因.采用实时定量PCR法对所筛选差异表达基因的表达水平做进一步测定,验证芯片数据的结果,并对这些特征性差异表达基因进行验证.结果 通过芯片杂交,分析筛选获得实验黄牛组来源虫体特征性差异表达基因3个,水牛组来源虫体4个,山羊组来源虫体7个.其中黄牛组2

  19. Histological observations on the distribution of three types of haemo-lymphocytes in Oncomelania hupensis (Gastropoda: Pomatiopsidae) infected with Schistosoma japonicum%感染日本血吸虫的湖北钉螺三种血淋巴细胞分布的组织学观察

    Institute of Scientific and Technical Information of China (English)

    Theerakamol Pengsakul; Yassir A Suleiman

    2013-01-01

    中,我们对于阴性湖北钉螺( O.hupensis)和感染日本血吸虫(Schistosoma japonicum)的阳性湖北钉螺(O.hupensis)的血淋巴细胞进行了定性和定量的比较研究.方法 分别在培养后3、5、7、12、16、20、25、30、35、40、45、50、55、60、65、70、75、80、85和90 d对其进行连续组织切片和H & E染色观察.结果 发现血淋巴细胞具有一个圆形的核,在其被染成深蓝色的细胞质中有一些密集的颗粒状物质.根据细胞核的体积,血淋巴细胞可以分为大、中和小3种类型,其直径分别为8.1~8.6 μm (大),5.5~6.0 μm (中),4.2~4.7 μm (小).通过对湖北钉螺(O.hupensis)的足部、围心腔、胃肠道、消化腺以及生殖腺5个器官部位的血淋巴细胞计数观察发现感染日本血吸虫(S.japonicum)后的湖北钉螺(O.hupensis),这几处的血淋巴细胞数量都有所增加.湖北钉螺的血淋巴细胞在围心腔处最多,而在足部区域最少.这3种类型的血淋巴细胞在钉螺所有部位都有所增加,且中型血淋巴细胞最多,大型和小型血淋巴细胞较少.结论 本次研究中所得到的数据在湖北钉螺(O.hupensis)对于日本血吸虫(S.japonicum)的内在防御机制以及更有效的控制血吸虫病的深入研究中具有相当的意义.日本血吸虫;湖北钉螺;血淋巴细胞;分布

  20. 3种青蒿素衍生物对日本血吸虫吡喹酮抗性株童虫的体内作用效果观察%In-vivo efficacy of three artesiminin derivatives against schistosomulum of praziquantel-resistant Schistosoma japonicum

    Institute of Scientific and Technical Information of China (English)

    卢萍; 汪伟; 曲国立; 戴建荣; 梁幼生

    2014-01-01

    目的:观察3种青蒿素衍生物双氢青蒿素、青蒿琥酯和蒿甲醚对日本血吸虫吡喹酮抗性株童虫的体内作用效果。方法以经11轮亚治疗剂量吡喹酮筛选的日本血吸虫为吡喹酮抗性株,以未暴露于吡喹酮的日本血吸虫作为吡喹酮敏感株,收集2虫株尾蚴感染小鼠,以300 mg/kg双氢青蒿素、青蒿琥酯和蒿甲醚对感染后7~8 d童虫分别进行2次灌服用药(总剂量600 mg/kg),所有小鼠于感染后45 d解剖,收集小鼠体内成虫并计数,计算减虫率和减雌率。结果300 mg/kg双氢青蒿素、蒿甲醚和青蒿琥酯2日疗法(总剂量600 mg/kg)对日本血吸虫吡喹酮敏感株7~8 d童虫的减虫率为69.8%~71.0%,减雌率为75.4%~79.8%;对日本血吸虫吡喹酮抗性株7~8 d童虫的减虫率为64.6%~66.1%,减雌率为69.3%~71.1%,差异均无统计学意义(均P>0.05)。结论日本血吸虫吡喹酮抗性株对青蒿素类衍生物双氢青蒿素、青蒿琥酯和蒿甲醚依然敏感,青蒿素衍生物与吡喹酮在日本血吸虫中不存在交叉抗药性。%Objective To evaluate the in-vivo efficacy of three artemisinin derivatives artemether, artesunate and dihydroartemisinin against schistosomulum of praziquantel-resistant Schistosoma japonicum,. Methods The S. japonicum subjected to subcurative dose of praziquantel for 11 rounds was served as a praziquantel-resistant strain, while the field-derived strain without exposure to praziquantel was served as a praziquantel-susceptible strain. The mice infected with the two strains of cercaria were treated with artemether, artesunate and dihydroartemisinin at a single dose of 300 mg/kg by gavage in days 7 and 8 post-infection, respectively. All mice were dissected 45 days post-infection, and the adult worms were collected to estimate worm and female worm burden reductions caused by drug treatment. Results Administration of artemether, artesunate and dihydroartemisinin at a single

  1. Scanning electron microscope observation on tegumental damage of 21-d-old Schistosoma japonicum induced by praziquantel%吡喹酮对21-d日本血吸虫童虫皮层损害的扫描电镜观察

    Institute of Scientific and Technical Information of China (English)

    肖树华; 沈炳贵

    1995-01-01

    AIM: To study the effect of praziquantel (Pra) on the tegument of 21-d-old schistosomula, mice infected with Schistosoma japonicum cercariae for 21 d were treated ig with Pra at a single dose. METHOD: Groups of mice were killed at different intervals within 48 h, and the worms were collected by perfusion for scanning electron microscopic observation. RESULTS: When the dose used was moderate swelling, fusion or even erosion and collapsed of the tegumental ridges, which was characterized by swelling of the discoid sensory structures. At higher dose of 500 mg were seen, but more extensive and serious.d, severe swelling, erosion and peeling of the tegument accompanied by the attachment of the host leukocytes on the damaged surface were seen. CONCLUSION: Pra exhibited a direct killing effect on 21-d-old schistosomula.%目的:观察吡喹酮对21-d童虫皮层的作用.方法:小鼠于感染日本血吸虫尾蚴达21 d时,ig1剂吡喹酮,并在治疗后1-48 h的不同时间内剖杀取虫,作扫描电镜观察.结果:吡喹酮的剂量为300 mg·kg-1时,宿主体内的21-d童虫示有轻度或中度的皮层褶嵴肿胀、融合、糜烂或破溃,且以盘状感觉器的肿胀为特征.用吡喹酮的较高剂量500 mg·kg-1治疗,虫的体表亦有相似的变化,但较广泛和严重.若每dig吡喹酮500 mg·kg-1,连给3 d,则虫的皮层严重肿、糜烂和剥落,并伴有宿主的白细胞附着.结论:结果表明,吡喹酮对21-d童虫有直接杀死作用.

  2. 蒿甲醚或吡喹酮早期治疗感染血吸虫尾蚴兔和犬的肝脏显微镜检查%Microscopic observations on livers of rabbits and dogs infected with Schistosoma japonicum cercariae and early treatment with artemether or praziquantel

    Institute of Scientific and Technical Information of China (English)

    肖树华; 杨元清; 张超威; 尤纪青

    1996-01-01

    To study the histopathological change of the liver of the hosts treated with artemether (Art) or praziquantel (Pra) in early stage after infection with Schistosoma japonicum cercariae. METHODS:Dogs infected once with schistosome cercariae were by the repeated dosing once every 1 or 2 wk for 2 -4 times. In rabbits, infected with 48 - 52 schistosome cercariae once every other day for 5 times,infection, followed by the repeated dosing every 1 or 2 wk for 2 - 3 times. RESULTS: After above mentioned dogs or rabbits were treated ig with Art,ArtC or Pra, the female worm reduction rates were 92.1% - 100 %. Histopathological examination showed that the reduction rates of total granuloma in the liver sections of the dogs and rabbits were 70.9 % - 97.3 % and 76.5 % - 97.4 %, respectively. Meantime, the structure of the hepatic lobules was normal with normal arrangement of the liver bundle. CoNCLusIoNS: Early treatment with Art or Pra exhibited a promising effect of protection of the liver of the dogs and rabbits infected with schistosome cercariae.%观察感染血吸虫尾蚴后早期用蒿甲醚(Art)或吡喹酮(Pra)治疗,对宿主肝组织的影响.方法:犬感染198-202条尾蚴后d 7ig Art 10 mg·kg-1,Art胶囊(ArtC)15 mg·kg-1或感染后d 21ig Pra 30-40 mg·kg-1,1-2 wk重复给药1次,共2-4次;兔每隔日感染48-52条尾蚴,共5次,并于第1次感染后d 7或d 21 ig 上述剂量的Art和Pra,停药后4-5 wk剖杀取肝作切片观察.结果:犬与兔经Art或Pra早期治疗后,减♀虫率达92.1%-100%,肝切片中的总虫卵肉芽肿数分别减少70.9%-97.3%和76.5%-97.4%,肝叶结构和肝索排列正常.结论:2种药物早期治疗对宿主肝脏有保护作用.

  3. Protective effect of SjC23-Hsp70 DNA vaccine and interleukin-12 on Schistosoma japonicum infection in water buffalos%日本血吸虫SjC23-Hsp70 DNA疫苗与IL-12对水牛保护性作用的研究

    Institute of Scientific and Technical Information of China (English)

    胡平成; 夏大; 崔虹艳; 张苹芳; 何永康; 喻鑫玲; 孙振球

    2012-01-01

    目的:研究日本血吸虫中国大陆株23 kD膜蛋白-热休克蛋白(SjC23-Hsp70)DNA疫苗联合佐剂白细胞介素12(IL-12)质粒DNA对水牛的免疫保护作用.方法:将血吸虫病非流行区8~10月龄健康水牛45头随机分为A组(SjC23-Hsp70+IL-12)、B组(SjC23+IL- 12)和C组(pVAX+IL-12),每组15头.每头牛经肩部肌注免疫3次,每次间隔28 d.末次免疫后28 d,每头牛感染日本血吸虫尾蚴1000条.解剖前2天及当天分别收集粪便1次,用定量法检测虫卵和毛蚴数.攻击感染后56天解剖所有水牛,经胸主动脉灌冲法收集成虫,计数成虫数,检测每克肝组织虫卵数.结果:A,B组与C组相比,分别获得45.70%和26.61%的减雌率,44.51%和25.84%的减虫率,41.10%和31.63%的减粪卵率,48.11%和38.07%的减毛蚴率及43.39%和31.95%的减肝卵率.A组的5个率均比B组高(P<0.05).结论:用SjC23-Hsp70 DNA疫苗和IL-12联合免疫水牛可获得明显的免疫保护作用.%Objective: To determine the immune-protective effect of Japan Schistosoma (Chinese mainland strain) 23 kD membrane protein-heat shock protein (SjC23-Hsp70) DNA vaccine plus adjuvant-induced interleukin-12 (IL-12) plasmid DNA on Schistosoma japonicum infection in water buffalos. Methods: Forty-five health water buffalos (8-10 months old) in non-endemic area of schistosomiasis were randomly assigned into group A (SjC23-Hsp70+IL-12, 300 μg), group B (SjC23+IL-12, 300 μg) and group C (pVAX+IL-12, 300 μg), 15 in each group. Each buffalo was immuned by shoulder intramuscular injection for 3 times, at an interval of 28 days. Twenty-eight days after the last immunization, each buffalo was infected with 1000 Japan cercariae of Schistosoma. Fecal examinations were conducted 2 days and 1 day before the perfusion, and on the day of perfusion. The number of hatching miracidia and eggs per gram feces was recorded. Fifty-six days after the infection, the buffalos were sacrificed and perfused via the descending

  4. Tryptophan auxotrophs of Rhizobium japonicum.

    OpenAIRE

    Wells, S E; Kuykendall, L D

    1983-01-01

    Eleven tryptophan-requiring mutants of Rhizobium japonicum I-110 ARS were isolated after nitrous acid mutagenesis and fell into five groups based on characterization by supplementation with intermediates and enzyme assays.

  5. A study of the effects of Schistosoma japonicum soluble egg antigen on CD4+CD25+regulatory T cells in patients with asthma%CD4+CD25+调节性T细胞在血吸虫可溶性虫卵抗原影响哮喘中的作用研究

    Institute of Scientific and Technical Information of China (English)

    朱云娟; 刘佩梅; 杨秀珍; 刘霞; 吴增强; 纪伟华; 安桂珍; 沈悦云; 刘金霞; 李健

    2011-01-01

    Objective To study the relationship between Schistosoma japonicum soluble egg antigen (SEA) and asthma and the effects of SEA on CD4+ CD25+ regulatory T cells (CD4+ CD25+ Treg) and expression of the Foxp3 gene. Methods BALB/C mice were each injected with 50 μg SEA peritoneally and through the foot pad once a week for 4 weeks. In the control group, all injections were with normal saline. Then asthma was induced with ovalbumin (OVA) in all mice. After mice were sacrificed, the lungs were subjected to pathologic examination; the bronchoalveolar lavage fluid (BALF) was collected and different cells were classified and counted after smearing and staining. Spleen cells were separated and the percentage of CD4+ CD25+ Treg out of total CD4+ T cells was determined using flow cytometry. Total spleen RNA was prepared and synthesized into cDNA through reverse transcription; cDNA was subjected to PCR amplification to determine the level of Foxp3 mRNA expression. Results Mild pulmonary inflammation was observed in the SEA immunization group, whereas severe inflammation was observed in the control group. Staining of the BALF revealed that the SEA immunization group had a much lower BALF cell density than did the control group. In the SEA immunization group, the percentage of eosinophils out of total cells was(2. 22± 1. 52)% while it was (19. 93±4. 08)% in the control group. The difference between the 2 groups was statistically significant (P<0. 05). Flow cytometry revealed that the percentage of CD4+ CD25+ Treg out of total CD4+ T cells was (32. 24±2. 19) % in the SEA immunization group while it was (27. 41±2. 87) % in the control group. The difference between the 2 groups was statistically significant (P<0. 05). The level of Foxp3 mRNA expression was higher than that in the control group as well. Conclusion SEA inhibits the development of asthma to some extent and it seems influence immune regulation through its effect on CD4+CD25+Treg.%目的 研究血吸虫可溶性虫

  6. Physicochemical consequences of the perdeuteriation of glutathione S-transferase from S. japonicum

    OpenAIRE

    Brockwell, David; Yu, Lu; Cooper, Serena; Mccleland, Steven; Cooper, Alan; Attwood, David; Gaskell, Simon J.; Barber, Jill

    2001-01-01

    Glutathione S-transferase (GST) from Schistosoma japonicum has been prepared in both normal protiated (pGST) and fully deuteriated (dGST) form by recombinant DNA technology. Electrospray mass spectrometry showed that the level of deuteriation in dGST was 96% and was homogeneous across the sample. This result is attributed to the use of a deuterium-tolerant host Escherichia coli strain in the preparation of the protein. 10 heteroatom-bound deuteriums (in addition to the carbon-bound deuteriums...

  7. Ultrasonic and x-ray tomographic findings of Schistosomiasis Japonicum

    International Nuclear Information System (INIS)

    In the present study, attempts were made to classify the ultrasonic patterns of the liver infected with Schistosoma Japonicum. The calcification and fibrosis of the liver were evaluated by comparative investigation with an ultrasonogram and computed tomography (CT). Schistosomiasis Japonica was examined in 23 patients who were more than 45 years of age. It was diagnosed by liver needle biopsy, an intracutaneous test, or autopsy. The cases with a fish scale and network pattern had attenuation of the liver on ultrasonography and were unspecific on CT. Histological findings demonstrated moderate liver fibrosis. The cases with a sieve pattern had attenuation on ultrasonography, and the CT disclosed a retractive liver and the CT number of that liver was increased. Histological findings demonstrated a severe fibrotic liver. The cases with a mottled pattern had increased reflective spotty echo with an acoustic shadow, and the CT disclosed calcification. The histological findings demonstrated a marked calcification of the eggs. The cases with a mixed pattern, which consisted of mottled and sieve based on fish scale and network, had no retraction with less increase in the CT number. These results suggest that the peculiar reflective echo pattern of Schistosomiasis Japonica was due to not only calcification but also fibrosis of the liver. (author)

  8. Prenylated benzophenones from Triadenum japonicum.

    Science.gov (United States)

    Oya, Atsushi; Tanaka, Naonobu; Kusama, Taishi; Kim, Sang-Yong; Hayashi, Shigeki; Kojoma, Mareshige; Hishida, Atsuyuki; Kawahara, Nobuo; Sakai, Kanae; Gonoi, Tohru; Kobayashi, Jun'ichi

    2015-02-27

    Six new prenylated benzophenones, (-)-nemorosonol (1) and trijapins A-E (2-6), were isolated from the aerial parts of Triadenum japonicum. (-)-Nemorosonol (1) and trijapins A-C (2-4) have a common tricyclo[4.3.1.0(3,7)]decane skeleton, while 1 is an enantiomer of (+)-nemorosonol previously isolated from Clusia nemorosa. The absolute configuration of (-)-nemorosonol (1) was assigned by ECD spectroscopy. Trijapins A-C (2-4) are analogues of 1 possessing an additional tetrahydrofuran ring. Trijapins D (5) and E (6) are prenylated benzophenones with a 1,2-dioxane moiety and a hydroperoxy group, respectively. (-)-Nemorosonol (1) exhibited antimicrobial activity against Escherichia coli (MIC, 8 μg/mL), Staphylococcus aureus (MIC, 16 μg/mL), Bacillus subtilis (MIC, 16 μg/mL), Micrococcus luteus (MIC, 32 μg/mL), Aspergillus niger (IC50, 16 μg/mL), Trichophyton mentagrophytes (IC50, 8 μg/mL), and Candida albicans (IC50, 32 μg/mL), while trijapin D (5) showed antimicrobial activity against C. albicans (IC50, 8 μg/mL). PMID:25602977

  9. Development and evaluation of a sensitive PCR-ELISA system for detection of schistosoma infection in feces.

    Directory of Open Access Journals (Sweden)

    Luciana Inácia Gomes

    Full Text Available BACKGROUND: A PCR-enzyme-linked immunosorbent assay (PCR-ELISA was developed to overcome the need for sensitive techniques for the efficient diagnosis of Schistosoma infection in endemic settings with low parasitic burden. METHODOLOGY/PRINCIPAL FINDINGS: This system amplifies a 121-base pair tandem repeat DNA sequence, immobilizes the resultant 5' biotinylated product on streptavidin-coated strip-well microplates and uses anti-fluorescein antibodies conjugated to horseradish peroxidase to detect the hybridized fluorescein-labeled oligonucleotide probe. The detection limit of the Schistosoma PCR-ELISA system was determined to be 1.3 fg of S. mansoni genomic DNA (less than the amount found in a single cell and estimated to be 0.15 S. mansoni eggs per gram of feces (fractions of an egg. The system showed good precision and genus specificity since the DNA target was found in seven Schistosoma DNA samples: S. mansoni, S. haematobium, S. bovis, S. intercalatum, S. japonicum, S. magrebowiei and S. rhodaini. By evaluating 206 patients living in an endemic area in Brazil, the prevalence of S. mansoni infection was determined to be 18% by examining 12 Kato-Katz slides (41.7 mg/smear, 500 mg total of a single fecal sample from each person, while the Schistosoma PCR-ELISA identified a 30% rate of infection using 500-mg of the same fecal sample. When considering the Kato-Katz method as the reference test, artificial sensitivity and specificity rates of the PCR-ELISA system were 97.4% and 85.1%, respectively. The potential for estimating parasitic load by DNA detection in feces was assessed by comparing absorbance values and eggs per gram of feces, with a Spearman correlation coefficient of 0.700 (P<0.0001. CONCLUSIONS/SIGNIFICANCE: This study reports the development and field evaluation of a sensitive Schistosoma PCR-ELISA, a system that may serve as an alternative for diagnosing Schistosoma infection.

  10. Pemberian Ekstrak Ganggang Cokelat dan Bradyrhizobium Japonicum untuk Meningkatkan Hara Nitrogen dan Produksi Tanaman Kedelai (Glycine max (L.) Merr.)

    OpenAIRE

    Indriyati, Ryrien

    2015-01-01

    This research aimed to determine the effect of brown seaweed extract and Bradyrhizobium japonicum and their interaction to increase N availability and Soybean Production. This research was conducted in the green house and Soil Biology laboratory of Fakultas Pertanian USU in Juny-October 2014, used Randomized Block Design (RBD) factorial consisting of 2 factors and 3 replications. The first factor was brown seaweed extract concentration consisting of 4 treatments (0, 10, 20 and 30 %/polybag) a...

  11. Establishment of Experimental Model of Hepatic Schistosoma Japonicum Egg Granulomas in Mice

    Institute of Scientific and Technical Information of China (English)

    冯振卿; 李玉华; 仇镇宁; 薛婉芬; 管晓虹

    1998-01-01

    IntroductionSchistosomaegggranulomasaretheprinci-palpathologicbasisofschistosomiasis.Toes-tablishanappropriateexperimentalmod...

  12. Resistance to niclosamide in Oncomelania hupensis, the intermediate host of Schistosoma japonicum: should we be worried?

    Science.gov (United States)

    Dai, Jian-Rong; Li, You-Zi; Wang, Wei; Xing, Yun-Tian; Qu, Guo-Li; Liang, You-Sheng

    2015-02-01

    As the currently only available molluscicide, niclosamide has been widely used for snail control for over 2 decades in China. There is therefore a concern about the emergence of niclosamide-resistant snail populations following repeated, extensive use of the chemical. The purpose of this study was to investigate the likelihood of niclosamide resistance in Oncomelania hupensis in China. Active adult O. hupensis snails derived from 20 counties of 10 schistosomiasis-endemic provinces of China, of 10 snails in each drug concentration, were immersed in solutions of 1, 0.5, 0.25, 0.125, 0.063, 0.032, 0.016 and 0.008 mg L-1 of a 50% wettable powder of niclosamide ethanolamine salt (WPN) for 24 and 48 h at 25 °C, and the median lethal concentration (LC50) was estimated. Then, the 24- and 48-h WPN LC50 values were compared with those determined in the same sampling sites in 2002. The results indicated that the 24- and 48-h WPN LC50 values for O. hupensis were not significantly different from those determined in 2002 (P = 0.202 and 0.796, respectively). It is concluded that the current sensitivity of O. hupensis to niclosamide has not changed after more than 2 decades of repeated, extensive application in the main endemic foci of China, and there is no evidence of resistance to niclosamide detected in O. hupensis. PMID:25003984

  13. Effect of artmether, hemin and Fe3+ on recombinant lactate dehydrogenase from Schistosoma japonicum

    Institute of Scientific and Technical Information of China (English)

    Gang Lu; Xuchu Hu; Can Huang; Yajun Lu; Lixian Wu; Lihua Li; Jing Xu; Xinbing Yu

    2010-01-01

    Objective: To explore antischitosome effects of artemether, hemin and Fe3+ on SjLDH. Methods:Enzyme activity of rSjLDH was assayed in the standard reaction system by adding different concentration of reagents (0.00-0.10 mM artemether, 0.00-0.02 mM hemin, 0.00-0.50 mM Fe3+). Same solvents of the each reagent were used as control. Results: There was no enzyme activity inhibition observed at 0.10 mM artemther; obivious inhibition for lactate oxidation reaction and pyruvate reduction reaction were detected at 0.002 mM and 0.004 mM of hemin, respectively;comparing with that of the control (P<0.05). The relative enzymatic activity inhibitions for pyruvate reduction reaction and lactate oxidation reaction at 0.02 mM hemin were 93.48% and 100.00%, respectively, comparing with that of the control (P<0.01); both pyruvate reduction and lactate oxidation reaction were inhibited completely at 0.50 mM Fe3+, comparing with that of the control (P<0.01). Conclusions: The results implied that SjLDH was not the direct molecular target of artemether. Hemin and Fe3+ are inhibitors of SjLDH.

  14. New Insight into the Antifibrotic Effects of Praziquantel on Mice in Infection with Schistosoma japonicum

    OpenAIRE

    Liang, Yue-jin; Luo, Jie; Yuan, Quan; Zheng, Dan; Liu, Ya-Ping; Shi, Lei; Zhou, Ying; Chen, Ai-Ling; Ren, Yong-Ya; Sun, Ke-Yi; Sun, Yan; Wang, Yong; Zhang, Zhao-Song

    2011-01-01

    Background Schistosomiasis is a parasitic disease infecting more than 200 million people in the world. Although chemotherapy targeting on killing schistosomes is one of the main strategies in the disease control, there are few effective ways of dealing with liver fibrosis caused by the parasite infection in the chronic and advanced stages of schistosomiasis. For this reason, new strategies and prospective drugs, which exert antifibrotic effects, are urgently required. Methods and Findings The...

  15. Molluscan response to parasite: Biomphalaria and Schistosoma mansoni interaction

    Directory of Open Access Journals (Sweden)

    D Negrão-Corrêa

    2007-11-01

    Full Text Available Digenetic trematodes use molluscs, almost always a Gastropoda, in their evolutive cycle, as intermediary hosts. The genus Schistosoma, with three main species that infect humans - S. mansoni, S. japonicum, and S. haematobium – shows a prevalence of 200 million patients in various countries worldwide, and 600 million people are still at risk of infection. S. mansoni is the most prevalent species, and Biomphalaria snails are its intermediary hosts. Although the campaigns of schistosomiasis control based on chemotherapy have reduced the morbidity and prevalence of this disease, transmission continues in almost all the areas submitted to intervention. One of the factors that has influence on the susceptibility of Biomphalaria to S. mansoni infection is ability of the host internal defense system (IDS to recognize and destroy the parasite. In Biomphalaria, the IDS is composed of cellular elements named hemocytes that act jointly with soluble components present in hemolymph, which could affect directly the larvae, or act in the recognition of the parasite, and activation of hemocytes. The susceptibility level of the mollusc has been attributed to the hemocyte capacity of involving and destroying the parasite, and this will be the centre of interest of this review.The study of S. mansoni and Biomphalaria interaction in resistant snail strains is important not only due to the academic-scientific value of this fascinating research area, but also to the potentially possible alternatives for the control of this endemia.

  16. Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

    Directory of Open Access Journals (Sweden)

    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.

  17. Ultrastructural and biochemical detection of biotin and biotinylated polypeptides in Schistosoma mansoni

    OpenAIRE

    1997-01-01

    Biotinylation is proposed for the identification of surface proteins in Schistosoma mansoni using the streptavidin-HRP conjugate for the detection of labeled polypeptides. However, control samples also showed several endogenous biotinylated polypeptides. In an attempt to determine the possibility of nonspecific binding between the streptavidin-HRP conjugate and polypeptides from S. mansoni, the conjugate was blocked with biotinamidecaproate-N-hydroxysuccinimide ester (BcapNHS) before biotin-s...

  18. Imatinib activity on Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Naftale Katz

    2013-11-01

    Full Text Available Imatinib, a drug used for treatment of human chronic myeloid leukaemia, due to its activity against protein kinases, has been also evaluated in vitro against Schistosoma mansoni showing high schistosomicidal activity. In the present experiments imatinib activity in vitro was confirmed at the doses of 25 µM, 50 µM and 100 µM. The first drug activity observed with the lower dose was interruption of egg-laying and with the higher dosages was the death of the worms. In mice infected with S. mansoni no activity was found even with 1,000 mg/kg/day, 500 mg/kg/day, single oral dose or when administered for three consecutive days. This is another example of the difference of results related to in vitro and in vivo trials using S. mansoni worms.

  19. 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

  20. Protein phosphorylation in Bradyrhizobium japonicum bacteroids and cultures.

    OpenAIRE

    Karr, D B; Emerich, D W

    1989-01-01

    Protein phosphorylation was demonstrated in Bradyrhizobium japonicum bacteroids in vivo and in cultures in vivo and in vitro. Comparison of in vivo-labeled phosphoproteins of bacteroids and of cultured cells showed differences in both the pattern and intensity of labeling. In cultured cells, comparison of the labeling patterns and intensities of in vivo- and in vitro-labeled phosphoproteins showed a number of similarities; however, several phosphoproteins were found only after one of the two ...

  1. Detection of Extracellular Enzyme Activities in Ganoderma neo-japonicum

    OpenAIRE

    Jo, Woo-Sik; Park, Ha-Na; Cho, Doo-Hyun; Yoo, Young-Bok; Park, Seung-Chun

    2011-01-01

    The ability of Ganoderma to produce extracellular enzymes, including β-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. β-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for β-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neo-japonic...

  2. Cerebral Schistosomiasis Caused by Schistosoma mansoni: a Case Report with Clinical Analysis

    Directory of Open Access Journals (Sweden)

    M Li

    2009-05-01

    Full Text Available "nCentral nervous system involvement arising from schistosomiasis is uncommon. It may be produced most fre­quently by Schistosoma japonicum infection, but reports of S. mansoni presenting as an intracerebral mass lesion are particularly rare. The authors describe the case of a 35-year-old woman with a 3-month history of partial epilep­tic seizures and head­aches. She immigrated to Egypt 4 years ago and had worked in Iraq for 2 years after the immigration. The patient's gen­eral physical and neurological examinations were unremarkable. Magnetic resonance (MR imaging revealed an enhanc­ing lesion with surrounding edema and mild mass effect in the left frontal lobe. A stereotactic brain biopsy demonstrated intraparenchymal granulomas surrounding S. mansoni eggs. S. mansoni was identified by stool examination. Prednisone (1 mg/kg per day for 1 week, with gradual with­drawal during the following 3 weeks and praziquantel (2 doses at 20 mg/kg per day therapy was initiated. The patient's symptoms resolved following medical treatment and the follow-up MR imaging yielded normal findings. This case is the rare imported case of cerebral schistosomiasis in China and the neuroschistosomiasis should be considered as the patient lived in a region in which this disease is endemic.

  3. Correlative and Dynamic Imaging of the Hatching Biology of Schistosoma japonicum from Eggs Prepared by High Pressure Freezing

    OpenAIRE

    Jones, Malcolm K.; Bong, Sze How; Green, Kathryn M.; Holmes, Philadelphia; Duke, Mary; Loukas, Alex; McManus, Donald P.

    2008-01-01

    Background Schistosome eggs must traverse tissues of the intestine or bladder to escape the human host and further the life cycle. Escape from host tissues is facilitated by secretion of immuno-reactive molecules by eggs and the formation of an intense strong granulomatous response by the host which acts to exclude the egg into gut or bladder lumens. Schistosome eggs hatch on contact with freshwater, but the mechanisms of activation and hatching are poorly understood. In view of the lack of k...

  4. Formation and Controlled Drug Release Using a Three-Component Supramolecular Hydrogel for Anti-Schistosoma Japonicum Cercariae

    OpenAIRE

    Yibao Li; Lei Zhu; Yulan Fan; Yayun Li; Linxiu Cheng; Wei Liu; Xun Li; Xiaolin Fan

    2016-01-01

    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 dem...

  5. Molecular characterization and ligand binding specificity of the PDZ domain-containing protein GIPC3 from Schistosoma japonicum

    OpenAIRE

    Mu Yi; Huang Haiming; Liu Shuai; Cai Pengfei; Gao Youhe

    2012-01-01

    Abstract Background Schistosomiasis is a serious global health problem that afflicts more than 230 million people in 77 countries. Long-term mass treatments with the only available drug, praziquantel, have caused growing concerns about drug resistance. PSD-95/Dlg/ZO-1 (PDZ) domain-containing proteins are recognized as potential targets for the next generation of drug development. However, the PDZ domain-containing protein family in parasites has largely been unexplored. Methods We present the...

  6. Gene : CBRC-ETEL-01-1376 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available 61 protein [Schistosoma japonicum] 2e-10 33% MPSRAKAQAYALAFPLPPCTMVFPPLPCTVVFLPLPCTMVFPPLPCTQRSLLSHAQWCSLFSHAQRCSLPLPCTMVFLPLPCT...MVVLSSSPXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXSPMHNSVALLSHVQWCSLLSPCTMIFLPLPCTMVFPPLPCTSLVCHAQWCSFLCLAQWCFLPLPCT...MVFPPLLFTMVFPPPLPCTTVFPPLPCTMVFPPLPCTMVFPPLPCTMVFPPLPCTMVFPRLPCTMVFPLLPCTMVFPPPLSCTMVFLPLPCTTVFPPLPYTIWYLGTQIILR ...

  7. [The interaction of Bradyrhizobium japonicum with clay minerals].

    Science.gov (United States)

    Kurdish, I K; Drobit'ko, A V; Shevchenko, T V; Mar'iushkin, V F

    2000-01-01

    It is shown that such clay minerals as palygorskite and montmorillonite stimulate growth activity of Bradyrhizobium japonicum. The bacteria come into contact with the above minerals. Granulated preparations of rhizobia have been developed on the basis of the results obtained. These preparations are characterized by the high yield of viable cells and a possibility of long-term storage. The use of montmorillonite in production of granulated preparations provides the higher yield of viable bacteria in the preparations and stability of their composition under long-term storage. PMID:10872286

  8. Role of Bradyrhizobium japonicum and Trichoderma spp. in the control of root rot disease of soybean

    Directory of Open Access Journals (Sweden)

    Syed Ehteshamul-Haque

    2014-08-01

    Full Text Available Seed treatment of soybean with Bndyrhizobium japonicum, Trichoderma harzianum, T. viride, T. hamatum, T. koningii and T. pseudokoningii significantly controlled the infection of 30-day-old seedlingsby Maerophomina phaseolina, Rhizoctonia solani and Fusarium spp. In 60-day-old plants Trichoderma spp.. and B. japonicum inhibited the grouth of R. solani and Fusarium spp., whereas the use of B. japonicum (TAL-102 with T. harzianum. T. viride, T. koningii and T. pseudokoningii controlled the infection by M. phaseolina. Greater grain yield was recorded when B. japonium (TAI-102 was used with T. hamatum.

  9. The cercarial glycocalyx of Schistosoma mansoni

    OpenAIRE

    1985-01-01

    Cercariae, the freshwater stage of Schistosoma mansoni infectious to man, are covered by a single unit membrane and an immunogenic glycocalyx. When cercariae penetrate the host skin, they transform to schistosomula by shedding tails, secreting mucous and enzymes, and forming microvilli over their surface. Here the loss of the glycocalyx from cercariae transforming in vitro was studied morphologically and biochemically. By scanning electron microscopy, the glycocalyx was a dense mesh composed ...

  10. 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.

  11. 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.

  12. Soybean Lectin Enhances Biofilm Formation by Bradyrhizobium japonicum in the Absence of Plants

    Directory of Open Access Journals (Sweden)

    Julieta Pérez-Giménez

    2009-01-01

    Full Text Available Soybean lectin (SBL purified from soybean seeds by affinity chromatography strongly bound to Bradyrhizobium japonicum USDA 110 cell surface. This lectin enhanced biofilm formation by B. japonicum in a concentration-dependent manner. Presence of galactose during biofilm formation had different effects in the presence or absence of SBL. Biofilms were completely inhibited in the presence of both SBL and galactose, while in the absence of SBL, galactose was less inhibitory. SBL was very stable, since its agglutinating activity of B. japonicum cells as well as of human group A+ erythrocytes was resistant to preincubation for one week at 60°C. Hence, we propose that plant remnants might constitute a source of this lectin, which might remain active in soil and thus favor B. japonicum biofilm formation in the interval between soybean crop seasons.

  13. [Grey correlation and cluster analysis on relationship between Cercidiphyllum japonicum community and its environment].

    Science.gov (United States)

    Pan, K; Liu, Z

    2001-04-01

    The relationship between 10 years old C. japonicum plantation forest community and its environmental conditions was studied by grey correlation method and cluster analysis. The results showed that there existed closer relations among soil organic matter, available Ca, Fe, Mg and N. Except for N and Mn, all soil available elements tested had no direct impact on the absorption and accumulation of corresponding elements by the community. The tree species in different habitats was found to absorb soil elements selectively to some extent. The factors affecting the basal diameter, DBH, height and biomass of C. japonicum could be lined as soil chemical characteristics > soil physical properties > climate factors, in which, available P had little impact on the growth of C. japonicum. It is suggested that C. japonicum could be restored in the area with higher air moisture and with fertile porous soil between elevation of 2200-2700 m. PMID:11757353

  14. Nitrogen fixing capacity of some soybean cultivars inoculated with different Rhizobium japonicum strains

    International Nuclear Information System (INIS)

    The nitrogen-fixing efficiency of different Rhizobium japonicum strains was tested. The strains were inoculated into three soybean cultivars and grain yield, total nitrogen content and nitrogen-fixing capacity were determined. 4 refs, 1 tab

  15. Resistance against Schistosoma mansoni induced by highly irradiated infections: studies on species specificity of immunization and attempts to transfer resistance

    Energy Technology Data Exchange (ETDEWEB)

    Bickle, Q.D.; Andrews, B.J.; Doenhoff, M.J.; Ford, M.J.; Taylor, M.G. (London School of Hygiene and Tropical Medicine, St. Albans (UK). Winches Farm Field Station)

    1985-01-01

    Significant levels of resistance against Schistosoma mansoni challenge were developed by mice exposed to highly irradiated (20 krad.) cercariae of the homologous species (53-67%), whereas vaccination with S. bovis, S. haematobium or S. japonicum failed to confer significant levels of resistance (-5-12%), thus confirming the specificity of the immunizing procedure. Attempts to transfer resistance to naive recipients by injection of serum and of spleen or lymph node cells from donor mice vaccinated with highly irradiated cercariae were largely unsuccessful. However, significant levels of resistance could be transferred to mice by injection of serum from rabbits exposed to irradiated cercariae. Comparable levels of resistance were conferred by injection of serum at the time of challenge (34-69%) or 5-6 days later (31-56%). In contrast, sera from rabbits injected with soluble egg antigen or homogenized cercariae failed to confer protection upon recipient mice. Sera from vaccinated mice, vaccinated rabbits and antigen-injected rabbits all caused cell adherence to skin-transformed schistosomula but neither the level of adherence nor the serum titre correlated with the ability to confer protection to mice.

  16. Resistance against Schistosoma mansoni induced by highly irradiated infections: studies on species specificity of immunization and attempts to transfer resistance

    International Nuclear Information System (INIS)

    Significant levels of resistance against Schistosoma mansoni challenge were developed by mice exposed to highly irradiated (20 krad.) cercariae of the homologous species (53-67%), whereas vaccination with S. bovis, S. haematobium or S. japonicum failed to confer significant levels of resistance (-5-12%), thus confirming the specificity of the immunizing procedure. Attempts to transfer resistance to naive recipients by injection of serum and of spleen or lymph node cells from donor mice vaccinated with highly irradiated cercariae were largely unsuccessful. However, significant levels of resistance could be transferred to mice by injection of serum from rabbits exposed to irradiated cercariae. Comparable levels of resistance were conferred by injection of serum at the time of challenge (34-69%) or 5-6 days later (31-56%). In contrast, sera from rabbits injected with soluble egg antigen or homogenized cercariae failed to confer protection upon recipient mice. Sera from vaccinated mice, vaccinated rabbits and antigen-injected rabbits all caused cell adherence to skin-transformed schistosomula but neither the level of adherence nor the serum titre correlated with the ability to confer protection to mice. (author)

  17. Erythronium japonicum attenuates histopathological lung abnormalities in a mouse model of ovalbumin-induced asthma.

    Science.gov (United States)

    Seo, Ji-Hye; Bang, Mi-Ae; Kim, Gyeyeop; Cho, Seung Sik; Park, Dae-Hun

    2016-05-01

    Asthma is a chronic lung condition that can induce mucus hypersecretion and pulmonary obstruction and may even cause death, particularly in children and older individuals. Erythronium japonicum (E. japonicum) is a traditional herb used in Korea and East Asian countries that has been found to exert free radical scavenging activity and anti-proliferative effects in human colorectal carcinoma cells. In the present study, we evaluated the anti-asthmatic effects of an extract of E. japonicum in a mouse model of ovalbumin (OVA)‑induced asthma. Female BALB/c mice were sensitized with an intraperitoneal injection of OVA and aluminum hydroxide hydrate on days 1 and 8 and then received the following treatments on days 21 to 25: i) control (no treatment), ii) sterilized tap water (given orally), iii) 1 mg/kg/day dexamethasone (administered orally), iv) 60 mg/kg/day E. japonicum extract, and v) 600 mg/kg/day E. japonicum extract. On the same days, all the mice except those in the control group were challenged 1 h later with nebulized 5% OVA for 30 min. We found that treatment with E. japonicum extract suppressed the OVA-induced increase in the number of white blood cells and decreased the IgE level in the bronchoalveolar lavage fluid samples obtained from the mice. Histopathological analysis of the lung tissues revealed that E. japonicum attenuated the asthma-related morphological changes in the mouse lung tissue, including the increased secretion of mucus in the bronchioles, eosinophil infiltration around the bronchioles and vessels, and goblet cell and epithelial cell hyperplasia. Immunohistochemical analysis revealed that treatment with E. japonicum extract suppressed the OVA-induced proliferation of T helper cells (CD4+) and B cells (CD19+) in the mouse lung tissue. Furthermore, treatment with E. japonicum extract modulated the expression of both T helper 2 cell-related factors [GATA binding protein 3 (GATA-3), tumor necrosis factor

  18. Schistosoma mansoni: cercarial responses to irradiance changes

    Energy Technology Data Exchange (ETDEWEB)

    Saladin, K.S.

    1982-02-01

    Cercariae of Schistosoma mansoni alternate between active swimming and passive drifting. They began swimming in response to either an increase or decrease in irradiance experienced during the passive phase. The number of cercariae reacting to a shadow was proportional to the magnitude of the stimulus. The shadow response may be mediated by the cercaria's ciliary receptors. About half as many cercariae reacted to an irradiance increase as to an equivalent decrease. This report is the first quantitative study of photosensory stimulus-response relationships in schistosome cercariae.

  19. Ectopic Schistosoma mansoni Eggs Inside a Lipoma.

    Science.gov (United States)

    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

  20. 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...

  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. Modeling and analysis of Schistosoma Argonaute protein molecular spatial conformation

    Directory of Open Access Journals (Sweden)

    Jianhua Zhang

    2011-08-01

    Conclusions: The information relationship between the structure and function of the Argonaute protein can be initially established with bioinformatics tools and the internet server, and this provides the theoretical basis for further clarifying the function of Schistosoma Argonaute protein.

  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. Differences in crystallization of two LinB variants from Sphingobium japonicum UT26

    International Nuclear Information System (INIS)

    To study enzyme functionality, two haloalkane dehalogenase variants LinB32 and LinB70 carrying single-point and double-point mutations were constructed and crystallized in different crystallization conditions. Both LinB variants and their complexes with halogenated substrates diffracted to resolutions ranging from 1.6 to 2.8 Å. Haloalkane dehalogenases are microbial enzymes that convert a broad range of halogenated aliphatic compounds to their corresponding alcohols by the hydrolytic mechanism. These enzymes play an important role in the biodegradation of various environmental pollutants. Haloalkane dehalogenase LinB isolated from a soil bacterium Sphingobium japonicum UT26 has a relatively broad substrate specificity and can be applied in bioremediation and biosensing of environmental pollutants. The LinB variants presented here, LinB32 and LinB70, were constructed with the goal of studying the effect of mutations on enzyme functionality. In the case of LinB32 (L117W), the introduced mutation leads to blocking of the main tunnel connecting the deeply buried active site with the surrounding solvent. The other variant, LinB70 (L44I, H107Q), has the second halide-binding site in a position analogous to that in the related haloalkane dehalogenase DbeA from Bradyrhizobium elkanii USDA94. Both LinB variants were successfully crystallized and full data sets were collected for native enzymes as well as their complexes with the substrates 1,2-dibromoethane (LinB32) and 1-bromobutane (LinB70) to resolutions ranging from 1.6 to 2.8 Å. The two mutants crystallize differently from each other, which suggests that the mutations, although deep inside the molecule, can still affect the protein crystallizability

  5. Osmotic stress tolerance, PGP traits and RAPD analysis of Bradyrhizobium japonicum strains

    Directory of Open Access Journals (Sweden)

    Marinković Jelena

    2013-01-01

    Full Text Available The osmotic stress tolerance of B. japonicum strains assessed according to their persistence in PEG solution. The lowest tolerance to osmotic stress was observed in strain 511 (43.3%, and the highest tolerance was observed for strain D216 (3.3% growth reduction in presence of PEG. PGP traits of B. japonicum strains were tested. None of five B. japonicum strains produced siderophore, strains 511 and 518 had the urease ability, and only B. japonicum 518 strain showed the ability to solubilize insoluble tricalcium phosphate. RAPD analysis, using AP10, BC318, AF14 and SPH1 primers, indicated genetic differences between Bradyrhizobium strains. The first group (strains 3, 6 and 518 showed more than 80% similarity. Strains 511 and D216 formed separate clusters. Difference between strains D216 and the other strains were more than 60%, with maximum value of 72% in comparison with strain 511. Plant-growth promoting (PGP traits, osmotic stress tolerance and RAPD analysis highlighted strain D216 as useful for further investigation of B. japonicum impact on drought reduction in symbiosis with soybean. [Projekat Ministarstva nauke Republike Srbije, br. TR 31022 i br. TR 31072

  6. Protein phosphorylation in Bradyrhizobium japonicum bacteroids and cultures

    International Nuclear Information System (INIS)

    Protein phosphorylation was demonstrated in Bradyrhizobium japonicum bacteroids in vivo and in cultures in vivo and in vitro. Comparison of in vivo-labeled phosphoproteins of bacteroids and of cultured cells showed differences in both the pattern and intensity of labeling. In cultured cells, comparison of the labeling patterns and intensities of in vivo- and in vitro-labeled phosphoproteins showed a number of similarities; however, several phosphoproteins were found only after one of the two labeling conditions. The labeling intensity was time dependent in both in vivo and in vitro assays and was dependent on the presence of magnesium in in vitro assays. Differences in the rates of phosphorylation and dephosphorylation were noted for a number of proteins. The level of incorporation of 32P into protein was only 2% or less of the total phosphate accumulated during the in vivo labeling period. Several isolation and sample preparation procedures resulted in differences in labeling patterns. Phosphatase inhibitors and several potential metabolic effectors had negligible effects on the phosphorylation pattern. There were no significant changes in the phosphorylation patterns of cells cultured on mannitol, acetate, and succinate, although the intensity of the labeling did vary with the carbon source

  7. Studies on mutation and repair in Rhizobium japonicum

    International Nuclear Information System (INIS)

    In the presence of NTG, Rhizobium japonicum loses viability very rapidly. 50% survival is achieved within 4 mins using 50 μgm/ml. When a constant time of 30 min is maintained then a concentration of 18 μgm/ml gives 50% survival. The low doses of NTG did not yield any auxotrophs. The antibiotics like penicillion, ampicillin and streptopenicillin were used as agents for enrichment of mutants, ampicillin was quite effective. A fairly efficient mechanism for repair from U.V. damage appears to exist. A greater part of this repair is due to the prevalence of dark repair mechanism. Mutants with increased sensitivity to U.V. repair failed to transform normally suggesting that the two processes of U.V. repair and genetic recombination may be related. The levels of deoxyribonucleases increased at the competent state. The activity at pH 7.5 and 8.4 but not at 5.5 was greater towards irradiated DNA, a prerequisite for any enzyme involved in U.V. repair. (author)

  8. Morphogenesis of Pistillate Flowers of Cercidiphyllum japonicum (Cercidiphyllaceae)

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ling Yan; Yi Ren; Xian-Hua Tian; Xiao-Hui Zhang

    2007-01-01

    Floral morphogenesis and the development of Cercidiphyllumjaponicum Sieb. et Zucc. were observed by scanning electron microscopy (SEM). The results showed that the pistillate inflorescences were congested spikes with the flowers arranged opposite. Great differences between the so-called "bract" and the vegetative leaf were observed both in morphogenesis and morphology. In morphogenesis, the "bract" primordium is crescent-shaped, truncated at the apex and not conduplicate,has no stipule primordium at the base but does have some inconspicuous teeth in the margin that are not glandular. The leaf primordium is triangular, cycloidal at the apex, conduplicate, has two stipule primordia at the base, has one gland-tooth at the apex occurring at first and some gland-teeth in the margin that occur later. In morphology, the "bract" is also different to the vegetative leaf in some characteristics that were also illustrated in the present paper. Based on the hypothesis that the bract is more similar to the vegetative leaf than the tepal, we considered that the so-called "bract" of C. japonicum might be the tepal of the pistillate flower in morphological nature. Therefore, each pistillate flower contains a tepal and a carpel.We did not find any trace of other floral organs in the morphogenesis of the pistillate flower. Therefore we considered that the unicarpellate status of extant Cercidiphyllum might be to highly reduce and advance characteristics that make the extant Cercidiphyllum isolated from both fossil Cercidiphyllum-like plants and its extant affinities.

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

    OpenAIRE

    Hany Sady; Al-Mekhlafi, Hesham M; Romano Ngui; Atroosh, Wahib M.; Al-Delaimy, Ahmed K.; Nasr, Nabil A.; Salwa Dawaki; Abdulsalam, Awatif M; Init Ithoi; Yvonne A. L. Lim; Kek Heng Chua; Johari Surin

    2015-01-01

    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-tim...

  10. Chemical composition and antimicrobial activity of essential oil isolated from the cultured mycelia of Ganoderma japonicum

    Institute of Scientific and Technical Information of China (English)

    Dandan Liu; Zheng Hu; Zhigang Liu; Bo Yang; Wenjuan Tu; Liang Li

    2009-01-01

    Objective:To explore a new natural antibiotic. Methods:The chemical composition of the essential oil from Ganoderma japonicum (G. japonicum) mycelia was analyzed by gas chromatography-mass spectrometry(GC-MS). The antimicrobial activity of the oil was evaluated against eighteen microorganisms, including bacteria, mildew and yeast by using a disc diffusion method. Furthermore, the minimum inhibitory concentrations(MIC) and the minimum bactericidal concentrations(MBC) of the essential oil against twelve clinical pathogens were determined. Results:The main components of the oil were nerolidol, decadienal, linaiool and benzyl alcohol. The antimicrobial results indicated that the oil inhibited all the tested bacterium, especially Methicillin-resistant Staphylococcus aureus (MRSA) in which the antibacterial activity exhibited a MBC of 1.03 mg/ml. Conclusion: The essential oil of G.japonicum mycelium has significant inhibitory activity. It is a potential medicinal resource that can be used as a natural antibiotic.

  11. Isolation and characterization of novel microsatellite loci for the endangered orchid Cypripedium japonicum (Orchidaceae)1

    Science.gov (United States)

    Yamashita, Yumi; Izuno, Ayako; Isagi, Yuji; Kurosawa, Takahide; Kaneko, Shingo

    2016-01-01

    Premise of the study: Twenty-six microsatellite markers were developed for the endangered orchid Cypripedium japonicum (Orchidaceae) to estimate the clonal diversity and genetic structure of the remaining populations in Japan. Methods and Results: Microsatellite loci of C. japonicum were isolated using Ion Personal Genome Machine (PGM) sequencing. The primer sets were tested on 55 ramets sampled from two populations in Japan. Sixteen loci showed polymorphism in at least one population, with two to five alleles per locus. Observed and expected heterozygosities for the two populations ranged from 0.00 to 0.92 and 0.00 to 0.71, respectively. Conclusions: The microsatellite markers developed here provide a useful tool to analyze clonal structure and sexual regeneration status and will help to manage the remaining genetic variation within C. japonicum. PMID:26949576

  12. Rhizobium japonicum mutants induced by gamma rays and some chemical mutagens

    International Nuclear Information System (INIS)

    Numerous symbiotic mutants of R.japonicum were isolated after UV irradiation or nitrosoguanidine mutagensis. Cultures of R.japonicum GM 377 were irradiated with 0, 25, 50, 75, 100, 150, 175, 200, 250 and 300 krad of gamma-rays. As for chemical mutagensis, cultures were treated with Sodium azide and colchicin at concentration of 1x10-6, 1x10-5, 5x10-5, 1x10-4, 5x10-4, 1x10-3 and 5x10-3 mol. Results revealed that gentamicin at concentration of 24.0 Mg/ml was able to kill all the populations of R.japonicum. Therefore, this concentration was used for mutants selection. However, numerous mutants at different freguencies were identified. The highest percentage of mutant was obtained with Sodium azide at 1x10-4 mol

  13. Molecular aspects of Schistosoma mansoni female maturation

    Directory of Open Access Journals (Sweden)

    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.

  14. 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

  15. Lethal and sublethal effects of thiamethoxam on the whitefly predator Serangium japonicum (Coleoptera: Coccinellidae) through different exposure routes.

    Science.gov (United States)

    Yao, Feng-Luan; Zheng, Yu; Zhao, Jian-Wei; Desneux, Nicolas; He, Yu-Xian; Weng, Qi-Yong

    2015-06-01

    Given expectations for a booming usage of thiamethoxam and increasing availability of the promising biological agent Serangium japonicum for the control of Bemisia tabaci in China, an evaluation of their compatibility is crucial for integrated pest management (IPM). This study examined the lethal and sublethal effects of thiamethoxam on S. japonicum through three exposure routes. An acute toxicity bioassay showed that LC50 values of thiamethoxam for S. japonicum through residue contact, egg-dip, and systemic treatment were 6.65, 4.37, and 2.43 mg AI L(-1), respectively. The prey consumption of S. japonicum given different densities of B. tabaci eggs under control, discontinuous, egg-dip and systemic exposure scenarios showed a good fit to a Type II functional response. Predation of S. japonicum was most affected under systemic exposure, followed by egg-dip, and discontinuous, which was only slightly affected. In all cases tested, however, predators recovered their predation capacity rapidly, either after 24h of exposure or 24h after the end of exposure. Thiamethoxam was highly toxic to S. japonicum regardless of exposure routes. Sublethal effects of thiamethoxam applied systemically or foliar both impaired the biological control of S. japonicum on B. tabaci. Therefore, thiamethoxam should be used with caution in IPM of B. tabaci. PMID:25655818

  16. Plant recognition of Bradyrhizobium japonicum nod factors. Final report, September 15, 1992--March 14, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Stacey, G.

    1998-01-01

    This grant had three objectives: (1) isolate and identify the unique nod factor metabolites made by different wild-type B. japonicum strains; (2) investigate the biological activity of these unique nod factors, especially as it relates to host range; and (3) initiate studies to define the mechanism of plant recognition of the nod factors. This report summarizes the results of this research.

  17. In Rhizobium japonicum the nitrogenase genes nifH and nifDK are separated.

    OpenAIRE

    Kaluza, K.; Fuhrmann, M.; Hahn, M.; Regensburger, B; Hennecke, H

    1983-01-01

    In contrast to Klebsiella pneumoniae or fast-growing Rhizobium species, such as R. meliloti, where the nitrogenase structural genes are clustered in one operon (nifHDK), in slow-growing Rhizobium japonicum 110, nifH and nifDK are on separate operons.

  18. Expression of symbiotic genes of Rhizobium japonicum USDA 191 in other rhizobia.

    OpenAIRE

    Appelbaum, E R; McLoughlin, T J; O'Connell, M.; Chartrain, N

    1985-01-01

    A 200-megadalton plasmid was mobilized from Rhizobium japonicum USDA 191 to other Rhizobium strains either that cannot nodulate soybeans or that form Fix- nodules on certain cultivars. The symbiotic properties of the transconjugants indicate that both soybean specificity for nodulation and cultivar specificity for nitrogen fixation are plasmid encoded.

  19. Proteomic Analysis of the Schistosoma mansoni Miracidium.

    Science.gov (United States)

    Wang, Tianfang; Zhao, Min; Rotgans, Bronwyn A; Strong, April; Liang, Di; Ni, Guoying; Limpanont, Yanin; Ramasoota, Pongrama; McManus, Donald P; Cummins, Scott F

    2016-01-01

    Despite extensive control efforts, schistosomiasis continues to be a major public health problem in developing nations in the tropics and sub-tropics. The miracidium, along with the cercaria, both of which are water-borne and free-living, are the only two stages in the life-cycle of Schistosoma mansoni which are involved in host invasion. Miracidia penetrate intermediate host snails and develop into sporocysts, which lead to cercariae that can infect humans. Infection of the snail host by the miracidium represents an ideal point at which to interrupt the parasite's life-cycle. This research focuses on an analysis of the miracidium proteome, including those proteins that are secreted. We have identified a repertoire of proteins in the S. mansoni miracidium at 2 hours post-hatch, including proteases, venom allergen-like proteins, receptors and HSP70, which might play roles in snail-parasite interplay. Proteins involved in energy production and conservation were prevalent, as were proteins predicted to be associated with defence. This study also provides a strong foundation for further understanding the roles that neurohormones play in host-seeking by schistosomes, with the potential for development of novel anthelmintics that interfere with its various life-cycle stages. PMID:26799066

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    BACKGROUND: In an effort to enhance accuracy of diagnosis of Schistosoma haematobium, this study explores day-to-day variability and diagnostic performance of real-time PCR for detection and quantification of Schistosoma DNA compared to other diagnostic tools in an endemic area before and after...... tool for detection of S. haematobium infections, with less day-to-day variation and higher sensitivity compared to microscopy. The superior performance of PCR before, and two and 18 months post-treatment provides a compelling argument for PCR as an accurate and reproducible tool for monitoring...

  1. 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)

  2. 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.

  3. Quantitative assessment of eosinophiluria in Schistosoma haematobium infections

    DEFF Research Database (Denmark)

    Reimert, C M; Mshinda, H M; Hatz, C F; Kombe, Y; Nkulila, T; Poulsen, Lars K.; Christensen, N O; Vennervald, B J

    2000-01-01

    Eosinophiluria, as quantified by measuring eosinophil cationic protein (ECP) in urinary extracts, microhematuria, egg excretion, and ultrasound-detectable bladder pathology were recorded in Schistosoma haematobium-infected Tanzanian school children at a baseline survey and during an 18-month post...

  4. Heart Block

    Science.gov (United States)

    ... the signal causes the heart to contract and pump blood. Heart block occurs if the electrical signal is ... degree heart block limits the heart's ability to pump blood to the rest of the body. This type ...

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Rhizobitoxine inhibition of hydrogenase synthesis in free-living Bradyrhizobium japonicum

    International Nuclear Information System (INIS)

    Rhizobitoxine produced by Bradyrhizobium species strongly prevented derepression of hydrogenase expression in free-living Bradyrhizobium japonicum, although the toxin had no effect on the activity of cells which had already synthesized hydrogenase protein. Dihydrorhizobitoxine, a structural analog of rhizobitoxine, proved to be a less potent inhibitor of hydrogenase derepression. Rhizobitoxine did not cause cell death at a concentration sufficient to eliminate hydrogenase expression. The large subunit of hydrogenase was not detectable with antibody after derepression in the presence of rhizobitoxine. The general pattern of proteins synthesized from 14C-labeled amino acids during derepression was not significantly different in the presence or absence of rhizobitoxine. These results indicated that rhizobitoxine inhibited hydrogenase synthesis in free-living B. japonicum. Cystathionine and methionine strongly prevented the inhibition of hydrogenase derepression by rhizobitoxine, suggesting that the inhibition involves the level of sulfur-containing amino acids in the cell

  7. Population Blocks.

    Science.gov (United States)

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  8. Characterization of a Bradyrhizobium japonicum ferrochelatase mutant and isolation of the hemH gene.

    OpenAIRE

    Frustaci, J M; O'Brian, M R

    1992-01-01

    A Tn5-induced mutant of Bradyrhizobium japonicum, strain LORBF1, was isolated on the basis of the formation of fluorescent colonies, and stable derivatives were constructed in backgrounds of strains LO and I110. The stable mutant strains LOek4 and I110ek4 were strictly dependent upon the addition of exogenous hemin for growth in liquid culture and formed fluorescent colonies. The fluorescent compound was identified as protoporphyrin IX, the immediate precursor of protoheme. Cell extracts of s...

  9. Aislamiento y caracterizaci??n de cepas de bradyrhizobium japonicum deficientes en el metabolismo del nitrato

    OpenAIRE

    Fern??ndez L??pez, Manuel

    1992-01-01

    Las membranas de bradyrhizobium japonicum pj17 cultivadas o incubadas microaerobicamente con nitrato expresan 2 isoenzimas nitrato reductasa (nr) cuyos tama??os moleculares son 160 kda y 200 kda. el isoenzima de 160 kda se expresa en respuesta a la microaerobiosis por si sola, mientras que la expresi??n del isoenzima de 200 kda requiere la presencia simultanea de condiciones microaerobicas y nitrato. Estos 2 isoenzimas son necesarios para la utilizaci??n microaerobica del nitrato ya que la au...

  10. Genome analysis of Bradyrhizobium japonicum serocluster 123 field isolates by using field inversion gel electrophoresis.

    OpenAIRE

    Sobral, B W; Sadowsky, M. J.; Atherly, A G

    1990-01-01

    The genomes of 11 Bradyrhizobium japonicum serocluster 123 field isolates were analyzed by using field inversion gel electrophoresis. Genomic fingerprints produced by digestion of intact genomic DNA in agarose plugs with the rare-cutting restriction enzymes AseI, DraI, SpeI, and XbaI showed that the isolates were genetically diverse. Few (30 to 50%) isolates exhibited the same fingerprint as the USDA serogroup strain with which they are antigenically related. Southern hybridization with a nif...

  11. Flavonol tetraglycosides and other constituents from leaves of Styphnolobium japonicum (Leguminosae) and related taxa.

    Science.gov (United States)

    Kite, Geoffrey C; Stoneham, Charlotte A; Veitch, Nigel C

    2007-05-01

    Two flavonol tetraglycosides comprising a trisaccharide at C-3 and a monosaccharide at C-7 were isolated from the leaves of Styphnolobium japonicum (L.) Schott and characterised as the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-glucopyranoside-7-O-alpha-rhamnopyranosides of quercetin and kaempferol. The 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-galactopyranoside-7-O-alpha-rhamnopyranoside of kaempferol, the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-glucopyranosides of kaempferol and quercetin and the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-galactopyranoside of kaempferol were also obtained from this species for the first time. Some or all of these flavonol tetra- and triglycosides were detected in 17 of 18 specimens of S. japonicum examined from living and herbarium material, although the most abundant flavonoid in the leaves was generally quercetin 3-O-alpha-rhamnopyranosyl(1-->6)-beta-glucopyranoside (rutin). The triglycosides, but not the tetraglycosides, were detected in herbarium specimens of Styphnolobium burseroides M. Sousa, Rudd & Medrano and Styphnolobium monteviridis M. Sousa & Rudd, but specimens of Styphnolobium affine (Torrey & A. Gray) Walp. contained a different profile of flavonol glycosides. The flavonol tetra- and triglycosides of S. japonicum were also present in leaves of Cladrastis kentukea (Dum. Cours.) Rudd, a representative of a genus placed close to Styphnolobium in current molecular phylogenies. An additional constituent obtained from leaves of Styphnolobium japonicum was identified as the maltol derivative, 3-hydroxy-2-methyl-4H-pyran-4-one 3-O-(4'-O-p-coumaroyl-6'-O-(3-hydroxy-3-methylglutaroyl))-beta-glucopyranoside. PMID:17462679

  12. Formation of Novel Polysaccharides by Bradyrhizobium japonicum Bacteroids in Soybean Nodules

    OpenAIRE

    Streeter, John G.; Salminen, Seppo O.; Whitmoyer, Robert E.; Carlson, Russell W

    1992-01-01

    Certain strains of Bradyrhizobium japonicum form a previously unknown polysaccharide in the root nodules of soybean plants (Glycine max (L.) Merr.). The polysaccharide accumulates inside of the symbiosome membrane—the plant-derived membrane enclosing the bacteroids. In older nodules (60 days after planting), the polysaccharide occupies most of the symbiosome volume and symbiosomes become enlarged so that there is little host cytoplasm in infected cells. The two different groups of B. japonicu...

  13. Functional diversity of Cercidiphyllum japonicum, communities in the Shennongjia Reserve, central China

    Institute of Scientific and Technical Information of China (English)

    Jintun Zhang; Bin Zhang; Zhiying Qian

    2015-01-01

    Functional diversity is significant to ecological processes of plant communities. We analyzed the variation of functional diversity of endangered species, Cercidi-phyllum japonicum, communities along an elevational gradient in the Shennongjia Reserve, central China. Sixty plots of 10 × 20 m from 1,350 to 2,050 m were set up and species composition, traits and environmental variables were measured and recorded. These data were analyzed using five functional diversity indices, functional attribute diversity, modified functional attribute diversity, plot based functional diversity, community based functional diversity and Rao’s functional diversity indices (Rao’s index), Functional diversities of C. japonicum communities were rich and varied greatly. Functional diversity declined non-linearly with increasing elevation. Functional diversity was significantly correlated with species richness and hetero-geneity. Elevation was a key environmental variable influencing functional diversity and species diversity. The five functional diversity indices were all effective for measuring functional diversity of communities. Functional diversity can be used as an indicator of conservation effi-ciency of endangered species such as C. japonicum.

  14. Role of nickel in membrane-bound hydrogenase and nickel metabolism in Rhizobium japonicum

    International Nuclear Information System (INIS)

    The membrane-bound hydrogenase of Rhizobium japonicum requires nickel for activity. Radioactive 63Ni co-migrates with hydrogenase activity in native gel systems and co-elutes with purified hydrogenase form an affinity matrix column. A simplified scheme for the purification of hydrogenase has been developed and constitutes the first report of the aerobic purification of this enzyme from R. japonicum. The aerobic purification utilizes the general affinity matrix. Reactive Red 120-agarose and results in higher specific activity and yield of enzyme than previously reported. The stability of aerobically purified hydrogenase to oxygen is substantially greater than that reported for anaerobically isolated enzyme. Reduction of the aerobically purified enzyme in the presence of oxygen, however, results in the rapid loss of activity. R. japonicum cells accumulate nickel during heterotrophic growth and as non-growing cells. The hydrogenase constitutive mutant SR470 accumulates substantially greater amounts of nickel under both conditions. Kinetic studies indicate that the nickel uptake system in the hydrogenase constitutive mutant SR470 is upregulated relative to SRwt cells. The uptake system is specific for nickel, although a 10-fold excess (relative to nickel) of copper or zinc inhibits nickel uptake. The nickel uptake system appears to require energy. Under nickel-free conditions hydrogenase protein is not synthesized as determined by cross-reactivity with antibodies directed against hydrogenase, indicating that nickel regulates the formation of the enzyme as well as being a constituent of the active protein

  15. In vivo activity of aryl ozonides against Schistosoma species.

    Science.gov (United States)

    Keiser, Jennifer; Ingram, Katrin; Vargas, Mireille; Chollet, Jacques; Wang, Xiaofang; Dong, Yuxiang; Vennerstrom, Jonathan L

    2012-02-01

    We evaluated the in vivo antischistosomal activities of 11 structurally diverse synthetic peroxides. Of all compounds tested, ozonide (1,2,4-trioxolane) OZ418 had the highest activity against adult Schistosoma mansoni, with total and female worm burden reductions of 80 and 90% (P < 0.05), respectively. Furthermore, treatment of S. haematobium-infected mice with OZ418 reduced the total worm burden by 86%. In conclusion, OZ418 is a promising antischistosomal lead compound. PMID:22106214

  16. In Vivo Activity of Aryl Ozonides against Schistosoma Species

    OpenAIRE

    Keiser, Jennifer; Ingram, Katrin; Vargas, Mireille; Chollet, Jacques; Wang, Xiaofang; Dong, Yuxiang; Vennerstrom, Jonathan L.

    2012-01-01

    We evaluated the in vivo antischistosomal activities of 11 structurally diverse synthetic peroxides. Of all compounds tested, ozonide (1,2,4-trioxolane) OZ418 had the highest activity against adult Schistosoma mansoni, with total and female worm burden reductions of 80 and 90% (P < 0.05), respectively. Furthermore, treatment of S. haematobium-infected mice with OZ418 reduced the total worm burden by 86%. In conclusion, OZ418 is a promising antischistosomal lead compound.

  17. Inhibition of surface membrane maturation in schistosomula of Schistosoma mansoni.

    OpenAIRE

    Wiest, P M; Tartakoff, A M; Aikawa, M.; Mahmoud, A. A.

    1988-01-01

    The surface membrane of the multicellular parasite Schistosoma mansoni is radically reorganized during the transformation of cercariae into schistosomula. The current study investigates factors involved in maturation of the surface from a trilaminate to a multilaminate membrane. When maturation was induced in the presence of puromycin (900 microM), the acquisition of a multilaminate surface and stainability with fluorescein-conjugated Con A were similar to that of control parasites. Similarly...

  18. Murine immunization by cesium-137 irradiation attenuated Schistosoma mansoni cercariae

    International Nuclear Information System (INIS)

    Cesium-137, becoming a more readily available ionizing gamma radiation source for laboratory use, was shown to effectively attenuate Schistosoma mansoni cercariae for vaccine production. In parallel comparison studies with the murine model, cesium-137 attenuated cercariae consistently afforded better protection than did the cobalt-60 prepared vaccine. Dose-response data indicated that the optimal total irradiation with cesium-137 was between 45 and 50 Krad

  19. Murine immunization by cesium-137 irradiation attenuated Schistosoma mansoni cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Stek, M. Jr.; Minard, P.; Cruess, D.F.

    1984-06-01

    Cesium-137, becoming a more readily available ionizing gamma radiation source for laboratory use, was shown to effectively attenuate Schistosoma mansoni cercariae for vaccine production. In parallel comparison studies with the murine model, cesium-137 attenuated cercariae consistently afforded better protection than did the cobalt-60 prepared vaccine. Dose-response data indicated that the optimal total irradiation with cesium-137 was between 45 and 50 Krad.

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

    OpenAIRE

    Krishnamurthy, Deepak; Katsikis, Georgios; 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...

  1. Cercarial glycocalyx of Schistosoma mansoni activates human complement.

    OpenAIRE

    Samuelson, J C; Caulfield, J. P.

    1986-01-01

    Human complement activation by cercariae and schistosomula of the human parasite Schistosoma mansoni was studied in vitro. Cercariae are composed of tails which are shed after infection of the host and bodies which transform into the larvae or schistosomula after infection. After incubation in fresh normal human serum (NHS), cercarial tails bound more anti-C3 antibodies than did cercarial bodies (CB), and the tails were rapidly lysed, while the attached CB remained intact. Complement activati...

  2. 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...

  3. Schistosoma mansoni: a rare cause of tubal infection

    OpenAIRE

    CA Faria; JCJ Conceição; TF Valadares; Rodrigues, B; L Carneiro

    2010-01-01

    S. haematobium is an important cause of urinary schistosomiasis, and symptomatic female genital infection is a common gynecological finding in areas where S. haematobium is prevalent. On the other hand, genital manifestations of intestinal schistosomas as S. mansoni are not frequent or are misdiagnosed. A case of a 40-year-old woman with abnormal uterine bleeding and asymptomatic tubal infection by S. mansoni identified in histological examination is presented.

  4. Pedigree analysis of Czech Holstein calves with schistosoma reflexum

    OpenAIRE

    Citek Jindrich

    2012-01-01

    Abstract Background Schistosoma reflexum (SR) is congenital syndrome briefly characterized by visceral eventration, severe dorsoflexion and ankylosis of the spine and arthrogryposis. A genetic etiology has been proposed, but conclusive evidence has not yet been provided. Methods Pedigree analysis was carried out in 29 cases of SR in Czech Holsteins and Holstein crosses. Genetic relationship was evaluated and inbreeding coefficients calculated. Pedigrees of 15 Czech Holsteins fathering non-SR ...

  5. The hmuQ and hmuD Genes from Bradyrhizobium japonicum Encode Heme-Degrading Enzymes

    OpenAIRE

    Puri, Sumant; O'Brian, Mark R.

    2006-01-01

    Utilization of heme by bacteria as a nutritional iron source involves the transport of exogenous heme, followed by cleavage of the heme macrocycle to release iron. Bradyrhizobium japonicum can use heme as an iron source, but no heme-degrading oxygenase has been described. Here, bioinformatics analyses of the B. japonicum genome identified two paralogous genes renamed hmuQ (bll7075) and hmuD (bll7423) that encode proteins with weak similarity to the heme-degrading monooxygenase IsdG from Staph...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  7. Oxygen-dependent catabolism of indole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Egebo, L A; Nielsen, S V; Jochimsen, B U

    1991-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity catalyzing the degradation of IAA and 5-hydroxy-indole-3-acetic acid. The activity requires...... oxygen-consuming opening of the indole ring analogous to the one catalyzed by tryptophan 2,3-dioxygenase. The pattern of metabolite usage by known tryptophan-auxotrophic mutants and studies of metabolites by high-performance liquid chromatography indicate that anthranilic acid is a terminal degradation...

  8. 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...

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

    Science.gov (United States)

    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. PMID:15652331

  10. T cell derived cytokines in lung-phase immunity to Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    R. A. Wilson

    1992-01-01

    Full Text Available In C57Bl/6 strain mice vaccinated with radiation-attenuated cercariae of Schistosoma mansoni immune elimination of challenge parasites occurs in the lungs. Leococytes were recovered from the lungs of such mice by bronchoalveolar lavage and cultured in vitro with larval antigen; the profile of cytokines released was then analyzed. From 14 days after vaccination, BAL cultures contained infiltrating lymphocytes wich produced abundant quantitties of IFN-g and IL-3. Challenge of vaccinated mice resulted in a second influx of IFN-g nd IL-3- producing cells, earlier than after vaccination or in the appropriate contropls. Ablation studies revealed that CD4+ T cells were the source of IFN-g. The timing of cytokine production after vaccination, and challenge was coincident with the phases of macrophage activation previously reported. At no time could lymphocytes in BAL cultures to stimulated to proliferate with either larval Ag or mitogen, in contrast to splenocytes from the same mice. Furthermore, T cell growth factor activity was not detected in BAL cultures stimulated with Ag. We suggest that the lymphocytes recruited to the lungs are memory/effector cells, When Ag. released challenge schistosomula is presented to these cells, they respond by secreting cytokines wich mediate the formation of cellular aggregates around the parasites, blocking their onward migration.

  11. Ultrastructural and biochemical detection of biotin and biotinylated polypeptides in Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Santos P.R.P.

    1997-01-01

    Full Text Available Biotinylation is proposed for the identification of surface proteins in Schistosoma mansoni using the streptavidin-HRP conjugate for the detection of labeled polypeptides. However, control samples also showed several endogenous biotinylated polypeptides. In an attempt to determine the possibility of nonspecific binding between the streptavidin-HRP conjugate and polypeptides from S. mansoni, the conjugate was blocked with biotinamidecaproate-N-hydroxysuccinimide ester (BcapNHS before biotin-streptavidin blotting. No bands were detected on the nitrocellulose sheet, demonstrating the specific recognition of biotin by the streptavidin present in the conjugate. Whole cercariae and cercarial bodies and tails showed several endogenous biotinylated polypeptides. The biotin concentration was 13 µg/190,000 cercariae. Adult worms presented less endogenous biotinylated polypeptides than cercariae. These results may be due to changes in the environment from aerobic to anaerobic conditions when cercarial bodies (schistosomula are transformed into adult worms and a decrease in CO2 production may occur. Cercariae, cercarial bodies and adult male worms were examined by transmission electron microscopy employing an avidin-colloidal gold conjugate for the detection of endogenous biotin. Gold particles were distributed mainly on the muscle fibers, but dispersed granules were observed in the tegument, mitochondria and cytosol. The discovery of endogenous biotin in S. mansoni should be investigated in order to clarify the function of this vitamin in the parasite

  12. Complete Genome Sequence of the Soybean Symbiont Bradyrhizobium japonicum Strain USDA6T

    Directory of Open Access Journals (Sweden)

    Nobukazu Uchiike

    2011-10-01

    Full Text Available The complete nucleotide sequence of the genome of the soybean symbiont Bradyrhizobium japonicum strain USDA6T was determined. The genome of USDA6T is a single circular chromosome of 9,207,384 bp. The genome size is similar to that of the genome of another soybean symbiont, B. japonicum USDA110 (9,105,828 bp. Comparison of the whole-genome sequences of USDA6T and USDA110 showed colinearity of major regions in the two genomes, although a large inversion exists between them. A significantly high level of sequence conservation was detected in three regions on each genome. The gene constitution and nucleotide sequence features in these three regions indicate that they may have been derived from a symbiosis island. An ancestral, large symbiosis island, approximately 860 kb in total size, appears to have been split into these three regions by unknown large-scale genome rearrangements. The two integration events responsible for this appear to have taken place independently, but through comparable mechanisms, in both genomes.

  13. Mitigation of nitrous oxide emissions from soils by Bradyrhizobium japonicum inoculation

    Science.gov (United States)

    Itakura, Manabu; Uchida, Yoshitaka; Akiyama, Hiroko; Hoshino, Yuko Takada; Shimomura, Yumi; Morimoto, Sho; Tago, Kanako; Wang, Yong; Hayakawa, Chihiro; Uetake, Yusuke; Sánchez, Cristina; Eda, Shima; Hayatsu, Masahito; Minamisawa, Kiwamu

    2013-03-01

    Nitrous oxide (N2O) is a greenhouse gas that is also capable of destroying the ozone layer. Agricultural soil is the largest source of N2O (ref. ). Soybean is a globally important leguminous crop, and hosts symbiotic nitrogen-fixing soil bacteria (rhizobia) that can also produce N2O (ref. ). In agricultural soil, N2O is emitted from fertilizer and soil nitrogen. In soybean ecosystems, N2O is also emitted from the degradation of the root nodules. Organic nitrogen inside the nodules is mineralized to NH4+, followed by nitrification and denitrification that produce N2O. N2O is then emitted into the atmosphere or is further reduced to N2 by N2O reductase (N2OR), which is encoded by the nosZ gene. Pure culture and vermiculite pot experiments showed lower N2O emission by nosZ+ strains and nosZ++ strains (mutants with increased N2OR activity) of Bradyrhizobium japonicum than by nosZ- strains. A pot experiment using soil confirmed these results. Although enhancing N2OR activity has been suggested as a N2O mitigation option, this has never been tested in the field. Here, we show that post-harvest N2O emission from soybean ecosystems due to degradation of nodules can be mitigated by inoculation of nosZ+ and non-genetically modified organism nosZ++ strains of B. japonicum at a field scale.

  14. Molecular identification and genetic variation of varieties of Styphnolobium japonicum (Fabaceae) using SRAP markers.

    Science.gov (United States)

    Sun, R X; Zhang, C H; Zheng, Y Q; Zong, Y C; Yu, X D; Huang, P

    2016-01-01

    Thirty-four Styphnolobium japonicum varieties were analyzed using sequence-related amplified polymorphism (SRAP) markers, to investigate genetic variation and test the effectiveness of SRAP markers in DNA fingerprint establishment. Twelve primer pairs were selected from 120 primer combinations for their reproducibility and high polymorphism. We found a total of 430 amplified fragments, of which 415 fragments were considered polymorphic with an average of 34.58 polymorphic fragments for each primer combination. The percentage of polymorphic fragments was 96.60%, and four primer pairs showed 100% polymorphism. Moreover, simple matched coefficients ranged between 0.68 and 0.89, with an average of 0.785, indicating that the genetic variation among varieties was relatively low. This could be because of the narrow genetic basis of the selected breeding material. Based on the similarity coefficient value of 0.76, the varieties were divided into four major groups. In addition, abundant and clear SRAP fingerprints were obtained and could be used to establish DNA fingerprints. In the DNA fingerprints, each variety had its unique pattern that could be easily distinguished from others. The results demonstrated that 34 varieties of S. japonicum had a relatively narrow genetic variation. Hence, a broadening of the genetic basis of breeding material is necessary. We conclude that establishment of DNA fingerprint is feasible by means of SRAP markers. PMID:27173318

  15. Schistosoma spindale infection in a captive jackal (Canis aureus).

    Science.gov (United States)

    Vimalraj, P G; Latchumikanthan, A

    2015-03-01

    This report is based on the findings from a captive jackal (Canis aureus) housed in Amirthi Zoological Park, Javadu Hills, Vellore. The animal was reported to be dull, depressed and also had diarrhea. Fecal samples were collected in 10 % formalin and subjected to direct and sedimentation method of faecal examination and was examined for endoparasitic infection. Surprisingly, fecal examination revealed two spindle shaped eggs having terminal spine with a size of 250μ by 60μ. The eggs were identified as belonging to Schistosoma spindale and as per the standard keys (Soulsby 1982). PMID:25698875

  16. Compatibility of Schistosoma mansoni Cameroon and Biomphalaria pfeifferi Senegal

    OpenAIRE

    Southgate, V. R.; Tchuem Tchuenté, L. A.; Théron, A.; JOURDANE, J; Ly, A.; Moncrieff, C. B.; B. Gryseels

    2000-01-01

    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 maxim...

  17. Ghost Block

    OpenAIRE

    Webb, Neil

    2011-01-01

    Filmed on the English south coast 'Ghost Block' depicts the uncanny and eerie atmosphere at the site of a WW2 coastal defence line. The concrete cubes were used as an anti-invasion blockade against potential landing forces. This protection line now slowly decaying and becoming enmeshed into the environment still acts as a defence to repel unwanted visitors. The area is a natural reserve to nesting birds that often lay eggs directly onto the beach surface. The blocks act as a final barrier ...

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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...

  20. Epidural block

    Science.gov (United States)

    ... Drugs & Supplements Videos & Tools Español You Are Here: Home ... It numbs or causes a loss of feeling in the lower half your body. This lessens the pain of contractions during childbirth. An epidural block may also be used to ...

  1. THE SUSCEPTIBILITY OF RECENT ISOLATES OF Schistosoma mansoni TO PRAZIQUANTEL

    Science.gov (United States)

    MENDONÇA, Adriana Maria B.; FEITOSA, Ana Paula S.; VERAS, Dyana L.; MATOS-ROCHA, Thiago J.; CAVALCANTI, Marília G. dos Santos; BARBOSA, Constança Clara G. S.; BRAYNER, Fábio A.; ALVES, Luiz C.

    2016-01-01

    Introduction: Schistosomiasis is a chronic disease caused by trematode flatworms of the genus Schistosoma and its control is dependent on a single drug, praziquantel (PZQ), but concerns over PZQ resistance have renewed interest in evaluating the in vitro susceptibility of recent isolates of Schistosoma mansoni to PZQ in comparison with well-established strains in the laboratory. Material and methods: The in vitro activity of PZQ (6.5-0.003 µg/mL) was evaluated in terms of mortality, reduced motor activity and ultrastructural alterations against S. mansoni. Results: After 3 h of incubation, PZQ, at 6.5 µg/mL, caused 100% mortality of all adult worms in the three types of recent isolates, while PZQ was inactive at concentrations of 0.08-0.003 µg/mL after 3 h of incubation. The results show that the SLM and Sotave isolates basically presented the same pattern of susceptibility, differing only in the concentration of 6.5 µg/mL, where deaths occurred from the range of 1.5 h in Sotave and just in the 3 h range of SLM. Additionally, this article presents ultrastructural evidence of rapid severe PZQ-induced surface membrane damage in S. mansoni after treatment with the drug, such as disintegration, sloughing, and erosion of the surface. Conclusion: According to these results, PZQ is very effective to induce tegument destruction of recent isolates of S. mansoni. PMID:26910445

  2. Gynecological Manifestations, Histopathological Findings, and Schistosoma-Specific Polymerase Chain Reaction Results Among Women With Schistosoma haematobium Infection: A Cross-sectional Study in Madagascar

    Science.gov (United States)

    Randrianasolo, Bodo Sahondra; Jourdan, Peter Mark; Ravoniarimbinina, Pascaline; Ramarokoto, Charles Emile; Rakotomanana, Fanjasoa; Ravaoalimalala, Vololomboahangy Elisabeth; Gundersen, Svein Gunnar; Feldmeier, Hermann; Vennervald, Birgitte Jyding; van Lieshout, Lisette; Roald, Borghild; Leutscher, Peter; Kjetland, Eyrun Floerecke

    2015-01-01

    Background. The pathophysiology of female genital schistosomiasis (FGS) is only partially understood. This study aims to describe the histopathological findings, polymerase chain reaction (PCR) results, and gynecological manifestations of FGS in women with different intensities of Schistosoma haematobium infection. Methods. Women aged 15–35 years living in an S. haematobium-endemic area in Madagascar underwent pelvic and colposcopic examinations. Small biopsy specimens were obtained from lesions and examined histopathologically. Schistosoma PCR was done on urine, biopsy, cervicovaginal lavage, and genital mucosal surface specimens. Results. Sandy patches and rubbery papules were found in 41 of 118 women (35%). Rubbery papules reflected an intense cellular immune reaction dominated by eosinophils, epithelial erosion, and viable ova. There was a significant decrease in the prevalence of rubbery papules with age, even after adjustment for urinary ova excretion. The sandy patches with grains showed moderate cellular immune reaction and ova (viable and/or calcified). They were most prevalent in cases with low-intensity urinary S. haematobium infection. Forty-two percent of women with Schistosoma-negative urine specimens had at least 1 genital specimen test positive for Schistosoma by PCR. Conclusions. The results indicate a diversity of lesions caused by S. haematobium and a dynamic evolution of the genital lesions. Schistosoma PCR may give an indication of the diagnosis. PMID:25725656

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

    Czech Academy of Sciences Publication Activity Database

    Fajtová, P.; Štefanić, S.; Hradilek, M.; Dvořák, Jan; Vondrášek, J.; Jílková, A.; Ulrychová, L.; McKerrow, J.H.; Caffrey, C.R.; Mareš, M.; Horn, M.

    2015-01-01

    Roč. 9, č. 6 (2015), e0003827. ISSN 1935-2735 Institutional support: RVO:60077344 Keywords : Schistosoma mansoni * schistosomiasis * prolyl oligopeptidase * blood fluke Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.446, year: 2014

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

    KAUST Repository

    Lepore, Rosalba

    2011-11-28

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

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

    OpenAIRE

    Fausto Edmundo Lima Pereira; Pedro Raso; Paulo Marcos Zech Coelho

    1986-01-01

    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 short...

  6. Analysis of regulatory protease sequences identified through bioinformatic data mining of the Schistosoma mansoni genome

    OpenAIRE

    Minchella Dennis J; Mayfield Chris; Bos David H

    2009-01-01

    Abstract Background New chemotherapeutic agents against Schistosoma mansoni, an etiological agent of human schistosomiasis, are a priority due to the emerging drug resistance and the inability of current drug treatments to prevent reinfection. Proteases have been under scrutiny as targets of immunological or chemotherapeutic anti-Schistosoma agents because of their vital role in many stages of the parasitic life cycle. Function has been established for only a handful of identified S. mansoni ...

  7. Lactate as a Novel Quantitative Measure of Viability in Schistosoma mansoni Drug Sensitivity Assays

    OpenAIRE

    Howe, Stephanie; Zöphel, Dorina; Subbaraman, Harini; Unger, Clemens; Held, Jana; Engleitner, Thomas; Hoffmann, Wolfgang H.; Kreidenweiss, Andrea

    2014-01-01

    Whole-organism compound sensitivity assays are a valuable strategy in infectious diseases to identify active molecules. In schistosomiasis drug discovery, larval-stage Schistosoma allows the use of a certain degree of automation in the screening of compounds. Unfortunately, the throughput is limited, as drug activity is determined by manual assessment of Schistosoma viability by microscopy. To develop a simple and quantifiable surrogate marker for viability, we targeted glucose metabolism, wh...

  8. Molecular confirmation of Schistosoma and family relationship in two ancient Egyptian mummies

    OpenAIRE

    Matheson, C. D.; David, R; Spigelman, M.; Donoghue, H. D.

    2014-01-01

    Egg morphology and immunocytochemistry have identified schistosomiasis in ancient Egypt. Our study aimedbto detect and characterize schistosomal DNA in mummified human tissue. Liver samples from the mummy Nekht-Ankh (c. 3900 BP) and intestinal samples from Khnum-Nakht, possibly his brother, were analyzed using PCR primers suitable for fragmented ancient DNA, specific for either Schistosoma mansoni or Schistosoma haematobium. Mitochondrial primers examined any relationship between the supposed...

  9. EFFECT OF FERULIC ACID ON CHEMOTAXIS AND NODULATION OF Bradyrhizobium japonicum

    OpenAIRE

    María C. Nápoles; A. Gutiérrez; E. Bordallo; Hernández, R.

    2001-01-01

    En este trabajo se estudió el efecto de tres concentraciones de ácido ferúlico sobre la quimiotaxis y la nodulación de B. japonicum ICA 8001. También se evaluó el efecto de este ácido hidroxicinámico obtenido a partir de vainillina, así como su capacidad de inducción sobre los genes de nodulación mediante la detección de factores Nod sintetizados. Se obtuvo una actividad quimiotáctica positiva pero no fuerte y solamente 10 mM como componente del medio de cultivo mostró una influencia positiva...

  10. Inhibition of hydrogenase synthesis by DNA gyrase inhibitors in Bradyrhizobium japonicum

    International Nuclear Information System (INIS)

    Derepression of an uptake hydrogenase in Bradyrhizobium japonicum is dependent on a microaerophilic environment. Addition of DNA gyrase inhibitors during derepression of hydrogenase specifically prevented expression of the hydrogenase enzyme. Antibodies to individual hydrogenase subunits failed to detect the protein after derepression in the presence of inhibitors, although there was no general inhibition of protein synthesis. The general pattern of proteins synthesized from 14C-labeled amino acids during derepression was no significantly different whether proteins were labeled in the presence or in the absence of gyrase inhibitors. In contrast, if transcription or translation was inhibited by addition of inhibitors of those functions, virtually no proteins were labeled during derepression. This indicated that most of the 14C-labeled proteins were synthesized de novo during derepression, synthesis of most proteins was unaffected by gyrase inhibitors, and the dependence of hydrogenase synthesis on gyrase activity was a specific one

  11. Quantitative Phosphoproteomic Analysis of Soybean Root Hairs Inoculated with Bradyrhizobium japonicum

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Tran H.; Brechenmacher, Laurent; Aldrich, Joshua T.; Clauss, Therese RW; Gritsenko, Marina A.; Hixson, Kim K.; Libault, Marc; Tanaka, Kiwamu; Yang, Feng; Yao, Qiuming; Pasa-Tolic, Ljiljana; Xu, Dong; Nguyen, Henry T.; Stacey, Gary

    2012-11-11

    Root hairs are single hair-forming cells on roots that function to increase root surface area, enhancing water and nutrient uptake. In leguminous plants, root hairs also play a critical role as the site of infection by symbiotic nitrogen fixing rhizobia, leading to the formation of a novel organ, the nodule. The initial steps in the rhizobia-root hair infection process are known to involve specific receptor kinases and subsequent kinase cascades. Here, we characterize the phosphoproteome of the root hairs and the corresponding stripped roots (i.e., roots from which root hairs were removed) during rhizobial colonization and infection to gain insight into the molecular mechanism of root hair cell biology. We chose soybean (Glycine max L.), one of the most important crop plants in the legume family, for this study because of its larger root size, which permits isolation of sufficient root hair material for phosphoproteomic analysis. Phosphopeptides derived from root hairs and stripped roots, mock inoculated or inoculated with the soybean-specific rhizobium Bradyrhizobium japonicum, were labeled with the isobaric tag 8-plex ITRAQ, enriched using Ni-NTA magnetic beads and subjected to nRPLC-MS/MS analysis using HCD and decision tree guided CID/ETD strategy. A total of 1,625 unique phosphopeptides, spanning 1,659 non-redundant phosphorylation sites, were detected from 1,126 soybean phosphoproteins. Among them, 273 phosphopeptides corresponding to 240 phosphoproteins were found to be significantly regulated (>1.5 fold abundance change) in response to inoculation with B. japonicum. The data reveal unique features of the soybean root hair phosphoproteome, including root hair and stripped root-specific phosphorylation suggesting a complex network of kinase-substrate and phosphatase-substrate interactions in response to rhizobial inoculation.

  12. An integrated biochemical system for nitrate assimilation and nitric oxide detoxification in Bradyrhizobium japonicum.

    Science.gov (United States)

    Cabrera, Juan J; Salas, Ana; Torres, María J; Bedmar, Eulogio J; Richardson, David J; Gates, Andrew J; Delgado, María J

    2016-02-01

    Rhizobia are recognized to establish N2-fixing symbiotic interactions with legume plants. Bradyrhizobium japonicum, the symbiont of soybeans, can denitrify and grow under free-living conditions with nitrate (NO3 (-)) or nitrite (NO2 (-)) as sole nitrogen source. Unlike related bacteria that assimilate NO3 (-), genes encoding the assimilatory NO3 (-) reductase (nasC) and NO2 (-) reductase (nirA) in B. japonicum are located at distinct chromosomal loci. The nasC gene is located with genes encoding an ABC-type NO3 (-) transporter, a major facilitator family NO3 (-)/NO2 (-) transporter (NarK), flavoprotein (Flp) and single-domain haemoglobin (termed Bjgb). However, nirA clusters with genes for a NO3 (-)/NO2 (-)-responsive regulator (NasS-NasT). In the present study, we demonstrate NasC and NirA are both key for NO3 (-) assimilation and that growth with NO3 (-), but not NO2 (-) requires flp, implying Flp may function as electron donor to NasC. In addition, bjgb and flp encode a nitric oxide (NO) detoxification system that functions to mitigate cytotoxic NO formed as a by-product of NO3 (-) assimilation. Additional experiments reveal NasT is required for NO3 (-)-responsive expression of the narK-bjgb-flp-nasC transcriptional unit and the nirA gene and that NasS is also involved in the regulatory control of this novel bipartite assimilatory NO3 (-)/NO2 (-) reductase pathway. PMID:26564204

  13. Condiloma acuminado anal com ovos de Schistosoma mansoni em paciente HIV-positivo Condilomata acuminata with Schistosoma eggs in HIV-positive patient

    Directory of Open Access Journals (Sweden)

    Fabiana Pirani Carneiro

    2007-06-01

    Full Text Available Condiloma acuminado e ovos de Schistosoma são freqüentemente encontrados na região anal, mas não há nenhum caso descrito de associação dessas doenças nessa região. No colo uterino a associação de infecção por HPV (vírus do papiloma humano e ovos de Schistosoma em paciente HIV (vírus da imunodeficiência humana-positivo já foi relatada e há evidências de que essa associação possa alterar a história natural dessas doenças. Assim como no colo uterino, é possível que essa interação também ocorra na região anal. Nosso objetivo, portanto, é relatar um caso de condiloma anal em paciente HIV-positivo, que foi submetido a ressecção cirúrgica e que apresentou no exame histopatológico numerosos ovos de Schistosoma mansoni.Condilomata acuminata and Schistosoma eggs are frequently found in the anal region, but there is no report about the association of these diseases in this region. The association of HPV infection and Schistosoma eggs in an HIV-positive patient was found in uterine cervix and there is evidence suggesting that this association can alters the natural history of these diseases. Like in the cervix, it is possible that this interaction also occurs in the anal region. So, we report a case of anal Condilomata acuminata, in an HIV-positive patient, that was ressected and contained on histopathologic examination, multiple Schistosoma eggs.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Immunization of mice with cobalt-60 irradiated Schistosoma mansoni cercariae

    International Nuclear Information System (INIS)

    Parameters of immunization of mice with 60Co-irradiated Schistosoma mansoni cercariae are described and related to protection against subsequent challenge infection. Such immunization was found to be dependent on dose of irradiation, number of immunizing cercariae, and number and time course of infections. Low levels of resistance were obtained with low irradiation doses, in contrast to previous studies in mice. In general, resistance increased with increasing irradiation doses, up to approximately 48 to 56 Kr. Maximal resistance (70 to 80%) was induced by a single exposure to 250 to 500 cercariae, irradiated at a dose rate of 2 Kr/minute to a total dose of 56 Kr, administered percutaneously 4 to 6 wk prior to challenge. Challenge could be delayed for at least 15 wk after immunization without a decrease in resistance. The resistance obtained was not attributable to a delayed migration of challenge worms

  16. Immunization of mice with cobalt-60 irradiated Schistosoma mansoni cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Minard, P.; Dean, D.A.; Jacobson, R.H.; Vannier, W.E.; Murrell, K.D.

    1978-01-01

    Parameters of immunization of mice with /sup 60/Co-irradiated Schistosoma mansoni cercariae are described and related to protection against subsequent challenge infection. Such immunization was found to be dependent on dose of irradiation, number of immunizing cercariae, and number and time course of infections. Low levels of resistance were obtained with low irradiation doses, in contrast to previous studies in mice. In general, resistance increased with increasing irradiation doses, up to approximately 48 to 56 Kr. Maximal resistance (70 to 80%) was induced by a single exposure to 250 to 500 cercariae, irradiated at a dose rate of 2 Kr/minute to a total dose of 56 Kr, administered percutaneously 4 to 6 wk prior to challenge. Challenge could be delayed for at least 15 wk after immunization without a decrease in resistance. The resistance obtained was not attributable to a delayed migration of challenge worms.

  17. Estudios inmunologicos en hamsters (Cricetus auratus infectados con Schistosoma mansoni

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    Eduardo Monge

    1986-08-01

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

  18. Structural bioinformatics study of PNP from Schistosoma mansoni.

    Science.gov (United States)

    da Silveira, Nelson José Freitas; Uchôa, Hugo Brandão; Canduri, Fernanda; Pereira, José Henrique; Camera, João Carlos; Basso, Luiz Augusto; Palma, Mário Sergio; Santos, Diógenes Santiago; de Azevedo, Walter Filgueira

    2004-09-10

    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. PMID:15313179

  19. 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...

  20. 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

  1. Blocked strainers

    International Nuclear Information System (INIS)

    Thermal insulation was the cause of the blockages that shut down five BWRs in Sweden. The main culprit was mineral wool installed when the plants started up. Physical degradation of the wool over the lifetime of the plant meant it could easily be washed out of place during a loss of coolant accident and could quickly block strainers in the emergency core cooling systems. The five BWRs are almost all back on line, equipped with larger strainers and faster backwashing capability. But the incident prompted more detailed investigation into how materials in the containment would behave during an accident. One material that caused particular concern is Caposil, a material often used to insulate the reactor vessel. Composed of natural calcium, aluminium silicates and cellulose fibres, in the event of a LOCA Caposil becomes particularly hazardous. Under high pressure, or when brought into contact with high pressure water and steam, Caposil fragments into 1 cm clumps, free fibres, and ''fines''. It is these fines which cause major problems and can block a strainer extremely quickly. The successful testing of a high performance water filter which can handle Caposil is described. (4 figures) (Author)

  2. 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

  3. The effect-enhancing and toxicity-reducing activity of Hypericum japonicum Thunb. extract in murine liver cancer chemotherapy

    OpenAIRE

    ZHANG, HONG-BO; Lu, Ping; CAO, WEN-BO; Zhang, Zhen-Hua; MENG, XIANG-LEI

    2012-01-01

    Chinese herbs are potential sources of antitumor drugs with immunoregulatory activity and few adverse effects. In the present study, we investigated whether the Hypericum japonicum Thunb. (HJT) extract enhanced the efficacy of 5-fluorouracil (5-FU) treatment in murine liver tumor xenografts and reduced toxicity of chemotherapy in hepatoma H22-bearing mice. Tumor weight and inhibition rate, thymus and spleen indices, as well as white blood cell (WBC) count were calculated. The phagocytic funct...

  4. Practical application of methanol-mediated mutualistic symbiosis between Methylobacterium species and a roof greening moss, Racomitrium japonicum.

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    Akio Tani

    Full Text Available Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production.

  5. Inoculation with Bradyrhizobium japonicum enhances the organic and fatty acids content of soybean (Glycine max (L.) Merrill) seeds.

    Science.gov (United States)

    Silva, Luís R; Pereira, Maria J; Azevedo, Jessica; Mulas, Rebeca; Velazquez, Encarna; González-Andrés, Fernando; Valentão, Patrícia; Andrade, Paula B

    2013-12-15

    Soybean (Glycine max (L.) Merrill) is one of the most important food crops for human and animal consumption, providing oil and protein at relatively low cost. The least expensive source of nitrogen for soybean is the biological fixation of atmospheric nitrogen by the symbiotic association with soil bacteria, belonging mainly to the genus Bradyrhizobium. This study was conducted to assess the effect of the inoculation of G. max with Bradyrhizobium japonicum on the metabolite profile and antioxidant potential of its seeds. Phenolic compounds, sterols, triterpenes, organic acids, fatty acids and volatiles profiles were characterised by different chromatographic techniques. The antioxidant activity was evaluated against DPPH, superoxide and nitric oxide radicals. Inoculation with B. japonicum induced changes in the profiles of primary and secondary metabolites of G. max seeds, without affecting their antioxidant capacity. The increase of organic and fatty acids and volatiles suggest a positive effect of the inoculation process. These findings indicate that the inoculation with nodulating B. japonicum is a beneficial agricultural practice, increasing the content of bioactive metabolites in G. max seeds owing to the establishment of symbiosis between plant and microorganism, with direct effects on seed quality. PMID:23993531

  6. Local Auxin Biosynthesis Mediated by a YUCCA Flavin Monooxygenase Regulates Haustorium Development in the Parasitic Plant Phtheirospermum japonicum.

    Science.gov (United States)

    Ishida, Juliane K; Wakatake, Takanori; Yoshida, Satoko; Takebayashi, Yumiko; Kasahara, Hiroyuki; Wafula, Eric; dePamphilis, Claude W; Namba, Shigetou; Shirasu, Ken

    2016-08-01

    Parasitic plants in the Orobanchaceae cause serious agricultural problems worldwide. Parasitic plants develop a multicellular infectious organ called a haustorium after recognition of host-released signals. To understand the molecular events associated with host signal perception and haustorium development, we identified differentially regulated genes expressed during early haustorium development in the facultative parasite Phtheirospermum japonicum using a de novo assembled transcriptome and a customized microarray. Among the genes that were upregulated during early haustorium development, we identified YUC3, which encodes a functional YUCCA (YUC) flavin monooxygenase involved in auxin biosynthesis. YUC3 was specifically expressed in the epidermal cells around the host contact site at an early time point in haustorium formation. The spatio-temporal expression patterns of YUC3 coincided with those of the auxin response marker DR5, suggesting generation of auxin response maxima at the haustorium apex. Roots transformed with YUC3 knockdown constructs formed haustoria less frequently than nontransgenic roots. Moreover, ectopic expression of YUC3 at the root epidermal cells induced the formation of haustorium-like structures in transgenic P. japonicum roots. Our results suggest that expression of the auxin biosynthesis gene YUC3 at the epidermal cells near the contact site plays a pivotal role in haustorium formation in the root parasitic plant P. japonicum. PMID:27385817

  7. Local Auxin Biosynthesis Mediated by a YUCCA Flavin Monooxygenase Regulates Haustorium Development in the Parasitic Plant Phtheirospermum japonicum[OPEN

    Science.gov (United States)

    Takebayashi, Yumiko; Kasahara, Hiroyuki; Wafula, Eric; dePamphilis, Claude W.; Namba, Shigetou

    2016-01-01

    Parasitic plants in the Orobanchaceae cause serious agricultural problems worldwide. Parasitic plants develop a multicellular infectious organ called a haustorium after recognition of host-released signals. To understand the molecular events associated with host signal perception and haustorium development, we identified differentially regulated genes expressed during early haustorium development in the facultative parasite Phtheirospermum japonicum using a de novo assembled transcriptome and a customized microarray. Among the genes that were upregulated during early haustorium development, we identified YUC3, which encodes a functional YUCCA (YUC) flavin monooxygenase involved in auxin biosynthesis. YUC3 was specifically expressed in the epidermal cells around the host contact site at an early time point in haustorium formation. The spatio-temporal expression patterns of YUC3 coincided with those of the auxin response marker DR5, suggesting generation of auxin response maxima at the haustorium apex. Roots transformed with YUC3 knockdown constructs formed haustoria less frequently than nontransgenic roots. Moreover, ectopic expression of YUC3 at the root epidermal cells induced the formation of haustorium-like structures in transgenic P. japonicum roots. Our results suggest that expression of the auxin biosynthesis gene YUC3 at the epidermal cells near the contact site plays a pivotal role in haustorium formation in the root parasitic plant P. japonicum. PMID:27385817

  8. Testicular schistosomiasis mimicking tumour

    Directory of Open Access Journals (Sweden)

    Nicola Mortati Neto

    2004-12-01

    Full Text Available Schistosomiasis or bilharziasis is a disease caused by Schistosoma. When infecting men the most common parasites are Schistosoma mansoni, Schistosoma japonicum and Schistosoma haematobium. The Schistosoma mansoni is the only endemic parasite in Brazil. We present a case of testicular schistosomiasis simulating malignancy. The case was treated successfully by excisional biopsy and praziquantel therapy. A review of the literature is discussed.

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

    Science.gov (United States)

    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

  10. EFFECT OF FERULIC ACID ON CHEMOTAXIS AND NODULATION OF Bradyrhizobium japonicum

    Directory of Open Access Journals (Sweden)

    María C. Nápoles

    2001-01-01

    Full Text Available En este trabajo se estudió el efecto de tres concentraciones de ácido ferúlico sobre la quimiotaxis y la nodulación de B. japonicum ICA 8001. También se evaluó el efecto de este ácido hidroxicinámico obtenido a partir de vainillina, así como su capacidad de inducción sobre los genes de nodulación mediante la detección de factores Nod sintetizados. Se obtuvo una actividad quimiotáctica positiva pero no fuerte y solamente 10 mM como componente del medio de cultivo mostró una influencia positiva sobre la nodulación. El ácido ferúlico sintetizado a partir de vainillina incrementó todos los parámetros de la nodulación. La actividad nod inductora de este ácido se evidenció con la producción de cuatro estructuras de lipoquitinoligosacáridos.

  11. Conservation Genetics of an Endangered Lady’s Slipper Orchid: Cypripedium japonicum in China

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    Xin Qian

    2014-06-01

    Full Text Available Knowledge about the population genetic variation of the endangered orchid, Cypripedium japonicum, is conducive to the development of conservation strategies. Here, we examined the levels and partitioning of inter-simple sequence repeat (ISSR diversity (109 loci in five populations of this orchid to gain insight into its genetic variation and population structure in Eastern and Central China. It harbored considerably lower levels of genetic diversity both at the population (percentage of polymorphic loci (PPL = 11.19%, Nei’s gene diversity (H = 0.0416 and Shannon’s information index (I = 0.0613 and species level (PPL = 38.53%, H = 0.1273 and I = 0.1928 and a significantly higher degree of differentiation among populations (the proportion of the total variance among populations (Φpt = 0.698 than those typical of ISSR-based studies in other orchid species. Furthermore, the Nei’s genetic distances between populations were independent of the corresponding geographical distances. Two main clusters are shown in an arithmetic average (UPGMA dendrogram, which is in agreement with the results of principal coordinate analysis (PCoA analysis and the STRUCTURE program. In addition, individuals within a population were more similar to each other than to those in other populations. Based on the genetic data and our field survey, the development of conservation management for this threatened orchid should include habitat protection, artificial gene flow and ex situ measures.

  12. Role of Bradyrhizobium japonicum induced by genistein on soybean stressed by water deficit

    Energy Technology Data Exchange (ETDEWEB)

    Napoles, M. C.; Guevara, E.; Montero, F.; Roosi, A.; Ferreira, A.

    2009-07-01

    Abstract The soybean (Glycine max (L.) Merr.) is a crop mainly grown under rain fed conditions although irrigation is increasingly being used. Water deficiency is the main factor limiting seed production. The symbiosis process is also negatively affected by water stress. The isoflavone genistein have been recognized as a powerful inducer of Nod factors production by Bradyrhizobium and its addition to inocula has been shown to increase nodule number and promote soybean nitrogen (N) fixation at low temperatures. This study looks for answers about the possible role of genistein in countering the stress on nodulation produced by water deficit in soybeans. Bradyrhizobium japonicum SEMIA 5079 was grown in culture media induced or not induced with genistein. Inocula were applied to plants growing at different moisture levels. The effect of the treatments on nodulation and N content was evaluated. An improved response to drought stress was observed when the bacteria were grown in presence of genistein as a Nod factors inducer. Nodulation values under moisture stress differed from 8.9 nodules plant{sup -}1 with genistein at 10 {mu}M to 1.8 nodules plant{sup -}1 when no inducer was used. Genistein reduced the negative effect on nodulation caused by water deficiency. (Author) 43 refs.

  13. Mutualistic co-evolution of type III effector genes in Sinorhizobium fredii and Bradyrhizobium japonicum.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Kimbrel

    2013-02-01

    Full Text Available Two diametric paradigms have been proposed to model the molecular co-evolution of microbial mutualists and their eukaryotic hosts. In one, mutualist and host exhibit an antagonistic arms race and each partner evolves rapidly to maximize their own fitness from the interaction at potential expense of the other. In the opposing model, conflicts between mutualist and host are largely resolved and the interaction is characterized by evolutionary stasis. We tested these opposing frameworks in two lineages of mutualistic rhizobia, Sinorhizobium fredii and Bradyrhizobium japonicum. To examine genes demonstrably important for host-interactions we coupled the mining of genome sequences to a comprehensive functional screen for type III effector genes, which are necessary for many Gram-negative pathogens to infect their hosts. We demonstrate that the rhizobial type III effector genes exhibit a surprisingly high degree of conservation in content and sequence that is in contrast to those of a well characterized plant pathogenic species. This type III effector gene conservation is particularly striking in the context of the relatively high genome-wide diversity of rhizobia. The evolution of rhizobial type III effectors is inconsistent with the molecular arms race paradigm. Instead, our results reveal that these loci are relatively static in rhizobial lineages and suggest that fitness conflicts between rhizobia mutualists and their host plants have been largely resolved.

  14. Molluscicidal Activity of Nerium indicum Mill, Pterocarya stenoptera DC, and Rumex japonicum Houtt on Oncomelania hupensis

    Institute of Scientific and Technical Information of China (English)

    HONG WANG; WEI-MIN CAI; WAN-XIAN WANG; JIAN-MIN YANG

    2006-01-01

    To evaluate the molluscicidal activities of three Chinese plants N. Indicum Mill, P. Stenoptera DC, and R.japonicum Houtt, and to clarify the molluscicidal mechanism. Methods N-butanol extracts and water extracts of the three plants were obtained. The reactions of EST isozyme, glycogen and total protein of snails to the plant extracts were studied.Results EST electrophoresis showed that EST was an important antidotal enzyme system and reacted strongly to environment.EST changed greatly during the whole exposure period so that it could be viewed as a pathological index of toxicity. Extracts decreased the glycogen content of the snails'soft tissues greatly, and also the protein content. Conclusion All extracts show strong molluscicidal activity. The LD50 value of the water extract of N. Indicum Mill is as low as 13.2 mg/L. EST can be viewed as a pathological index of toxicity. The energy metabolism abnormity is the key reason for the molluscicidal activities. The biochemical mechanism needs further research.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Early Detection of Schistosoma Egg-Induced Pulmonary Granulomas in a Returning Traveler.

    Science.gov (United States)

    Coron, Noémie; Le Govic, Yohann; Kettani, Sami; Pihet, Marc; Hemery, Sandrine; de Gentile, Ludovic; Chabasse, Dominique

    2016-03-01

    We report the case of a French traveler who developed acute pulmonary schistosomiasis 2 months after visiting Benin. He presented with a 1-month history of fever, cough, and thoracic pain. Initial investigations revealed hypereosinophilia and multiple nodular lesions on chest computed tomography scan. Lung biopsies were performed 2 months later because of migrating chest infiltrates and increasing eosinophilia. Histological examination showed schistosomal egg-induced pulmonary granulomas with ova exhibiting a prominent terminal spine, resembling Schistosoma haematobium. However, egg shells were Ziehl-Neelsen positive, raising the possibility of a Schistosoma intercalatum or a Schistosoma guineensis infection. Moreover, involvement of highly infectious hybrid species cannot be excluded considering the atypical early pulmonary oviposition. This case is remarkable because of the rarity of pulmonary schistosomiasis, its peculiar clinical presentation and difficulties in making species identification. It also emphasizes the need to consider schistosomiasis diagnosis in all potentially exposed travelers with compatible symptoms. PMID:26787142

  17. Pedigree analysis of Czech Holstein calves with schistosoma reflexum

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    Citek Jindrich

    2012-04-01

    Full Text Available Abstract Background Schistosoma reflexum (SR is congenital syndrome briefly characterized by visceral eventration, severe dorsoflexion and ankylosis of the spine and arthrogryposis. A genetic etiology has been proposed, but conclusive evidence has not yet been provided. Methods Pedigree analysis was carried out in 29 cases of SR in Czech Holsteins and Holstein crosses. Genetic relationship was evaluated and inbreeding coefficients calculated. Pedigrees of 15 Czech Holsteins fathering non-SR affected calves were used for comparison. Results Twenty-one cases occurred in one pedigree founded by three sires while three SR calves occurred in another pedigree with a common grandfather. The sex ratio between affected males and females was 11:6. Affected calves shared common ancestors different from those shared by the unaffected calves. The inbreeding coefficient in the SR affected calves was not increased compared to unaffected calves. Conclusions The findings are consistent with SR being inherited autosomal recessively. Further studies are however needed to confirm this and therefore a breeding trial is recommended where a suspected heterozygous sire is mated to closely related females.

  18. Serological screening of the Schistosoma mansoni adult worm proteome.

    Directory of Open Access Journals (Sweden)

    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. Effect of immunization on migration of Schistosoma mansoni through lungs

    Energy Technology Data Exchange (ETDEWEB)

    Minard, P.; Dean, D.A.; Vannier, W.E.; Murrell, K.D.

    1978-01-01

    Schistosoma mansoni schistosomula migrate through the lungs of infected mice; peak recovery occurs 6 days following infection. When cercariae were irradiated at /sup 60/Co doses of 24 to 64 Kr, the number of schistosomula recovered from lungs 6 days after infection decreased in a dose-dependent fashion. The pattern of lung migration of schistosomes irradiated at 56 Kr prior to infection was similar to that of nonirradiated schistosomes, but greatly reduced numbers were recovered. When mice were immunized by a single infection with 56 Kr attenuated cercariae 6 wk prior to challenge, the pattern of challenge migration through the lungs was altered. The number of schistosomes recovered increased rapidly between 2 and 6 days post-infection, and showed a plateau between 8 and 10 days with peak recovery occurring 10 days post-infection. This peak recovery was reduced in comparison to that of non-immunized mice, but did not account for all of the reduction observed at the adult worm stage.

  20. 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).

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

    International Nuclear Information System (INIS)

    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/m2. Worm and egg burdens, liver granuloma diameters and liver fibrosis showed minimal changes (2 administered in six treatments) did not impair the resistance to rechallenge conferred by vaccination with 60Co-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)

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Activity of praziquantel on in vitro transformed Schistosoma mansoni sporocysts

    Directory of Open Access Journals (Sweden)

    ACA Mattos

    2006-10-01

    Full Text Available Praziquantel (PZQ is effective against all the evolutive phases of Schistosoma mansoni. Infected Biomphalaria glabrata snails have their cercarial shedding interrupted when exposed to PZQ. Using primary in vitro transformed sporocysts, labeled with the probe Hoechst 33258 (indicator of membrane integrity, and lectin of Glycine max (specific for carbohydrate of N-acetylgalactosamine membrane, we evaluated the presence of lysosomes at this evolutive phase of S. mansoni, as well as the influence of PZQ on these acidic organelles and on the tegument of the sporocyst. Although the sporocyst remained alive, it was observed that there was a marked contraction of its musculature, and there occurred a change in the parasite's structure. Also, the acidic vesicles found in the sporocysts showed a larger delimited area after contact of the parasites with PZQ. Damages to the tegument was also observed, as show a well-marked labeling either with Hoechst 33258 or with lectin of Glycine max after contact of sporocysts with the drug. These results could partially explain the interruption/reduction mechanism of cercarial shedding in snails exposed to PZQ.

  4. Identification of Schistosoma mansoni candidate antigens for diagnosis of schistosomiasis

    Directory of Open Access Journals (Sweden)

    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.

  5. Ultra–Low-Cost Urine Filtration for Schistosoma haematobium Diagnosis: A Proof-of-Concept Study

    Science.gov (United States)

    Ephraim, Richard K. D.; Duah, Evans; Andrews, Jason R.; Bogoch, Isaac I.

    2014-01-01

    Simple, efficient, and cost-effective strategies are needed for urine sample preparation in the field diagnosis of infection with Schistosoma haematobium. In this proof-of-concept study, we evaluated inexpensive and widely available paper products (paper towels, school workbook paper, and newspaper) to gravity-filter urine containing 60 eggs/mL of Schistosoma haematobium. Eggs were reliably visualized by light microscopy by using single-ply paper towels as urine filters. This filtration method has broad applicability in clinical and public health settings in resource-constrained environments. PMID:24980496

  6. Ultra-low-cost urine filtration for Schistosoma haematobium diagnosis: a proof-of-concept study.

    Science.gov (United States)

    Ephraim, Richard K D; Duah, Evans; Andrews, Jason R; Bogoch, Isaac I

    2014-09-01

    Simple, efficient, and cost-effective strategies are needed for urine sample preparation in the field diagnosis of infection with Schistosoma haematobium. In this proof-of-concept study, we evaluated inexpensive and widely available paper products (paper towels, school workbook paper, and newspaper) to gravity-filter urine containing 60 eggs/mL of Schistosoma haematobium. Eggs were reliably visualized by light microscopy by using single-ply paper towels as urine filters. This filtration method has broad applicability in clinical and public health settings in resource-constrained environments. PMID:24980496

  7. 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...

  8. Sequences and characterization of hupU and hupV genes of Bradyrhizobium japonicum encoding a possible nickel-sensing complex involved in hydrogenase expression.

    OpenAIRE

    Black, L K; Fu, C.; Maier, R J

    1994-01-01

    A 2.7-kb DNA fragment of Bradyrhizobium japonicum previously shown to be involved in hydrogenase expression has been sequenced. The area is located just upstream of the hupSLCDF operon and was found to contain two open reading frames, designated hupU and hupV; these encode proteins of 35.4 and 51.8 kDa, respectively. These proteins are homologous to Rhodobacter capsulatus HupU, a possible repressor of hydrogenase expression in that organism. B. japonicum HupU is 54% identical to the N terminu...

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

    Directory of Open Access Journals (Sweden)

    Mutapi Francisca

    2002-01-01

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

  10. Genes for a microaerobically induced oxidase complex in Bradyrhizobium japonicum are essential for a nitrogen-fixing endosymbiosis.

    OpenAIRE

    Preisig, O; Anthamatten, D; Hennecke, H

    1993-01-01

    We report the discovery of a Bradyrhizobium japonicum gene cluster (fixNOQP) in which mutations resulted in defective soybean root-nodule bacteroid development and symbiotic nitrogen fixation. The predicted, DNA-derived protein sequences suggested that FixN is a heme b and copper-binding oxidase subunit, FixO a monoheme cytochrome c, FixQ a polypeptide of 54 amino acids, and FixP a diheme cytochrome c and that they are all membrane-bound. The isolation and analysis of membrane proteins from B...

  11. Polysaccharide-based bioflocculant template of a diazotrophic Bradyrhizobium japonicum 36 for controlled assembly of AgCl nanoparticles.

    Science.gov (United States)

    Rasulov, Bakhtiyor A; Pattaeva, Mohichehra A; Yili, Abulimiti; Aisa, Haji Akber

    2016-08-01

    A simple and green method was developed for the biosynthesis of silver chloride nanoparticles, free from silver nanoparticles, using polysaccharide-based bioflocculant of a diazotrophic rhizobacteria Bradyrhizobium japonicum 36 strain. The synthesized silver chloride nanoparticles were characterized by UV-vis, XRD, FT-IR and TEM. The concentration-dependent and controllable method for silver chloride nanoparticles was developed. The biosynthesized silver chloride nanoparticles exhibited strong antimicrobial activity towards pathogenic microorganisms such as Escherichia coli, Staphylococcus aureus and Candida albicans. The synthesized silver chloride nanoparticles can be exploited as a promising new biocide bionanocomposite against pathogenic microorganisms. PMID:27039118

  12. Ultrasound guided supraclavicular block.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2013-09-01

    Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.

  13. 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 ...

  14. Effect of Maternal Schistosoma mansoni Infection and Praziquantel Treatment During Pregnancy on Schistosoma mansoni Infection and Immune Responsiveness among Offspring at Age Five Years.

    OpenAIRE

    Tweyongyere, R; Naniima, P; Mawa, PA; Jones, FM; Webb, EL; Cose, S; Dunne, DW; Elliott, AM

    2013-01-01

    INTRODUCTION 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. ma...

  15. Lethal effect of oxamniquine and praziquantel on mice experimentally infected with Schistosoma mansoni Efeito letal de oxamniquina e praziquantel em camundongos experimentalmente infectados com Schistosoma mansoni

    OpenAIRE

    Sonia Maria A.F. Tonelli; Eugênio M. A. Goulart; Edward Tonelli; Paulo Marcos Zech Coelho

    1995-01-01

    Lethality caused by administration of oxamniquine and praziquantel to mice infected with Schistosoma mansoni, and their respective controls (uninfected), has been studied. As the results indicate, the infected animals clearly showed higher mortality rates when praziquantel was used. Surprisingly, it may be noted that exactly the contrary occurs in relation to the use of oxamniquine, inasmuch as marked higher mortality rates were seen in the control animals (uninfected). These observations lea...

  16. Studies concerning the photoreceptor pigments of stentor coeruleus and blepharisma japonicum

    International Nuclear Information System (INIS)

    In the presence of 1,8-bis-(dimethylamino)-naphthalene, solutions of 3-O-benzyl hypericin and 3,4-di-O-benzyl hypericin in aromatic solvents like benzene or toluene have shown to be photoreactive, whereas in the dark no reactions occurred. 3-O-benzyl hypericin was found to enter a photorearrangement reaction leading to a product species, whose structural details could be elicited by UV/VIS, NMR, and mass spectroscopy together with spectrophotometric titrations. Investigation results led to a 11-phenyl-11H-benz{4,10}anthra{2,1,9,8-nopqa}pleiadene skeleton forming the backbone of the photoproduct. This fundamental system is the more of interest since it highly resembles the parent compound of the blepharismins, the photoreceptor pigments of Blepharisma japonicum. In analogy to blepharismin C, which can be converted photochemically into oxyblepharismin C and further on into stentorin by treatment with acid, the photoproduct could be transformed into hypericin upon irradiation and additional acidic work up. As the photoproduct incorporates several equilibrium systems, computer aided calculations were executed to achieve an idea about the relative stability of the photoproduct's various isomeric forms. The described photoreaction represents a possible route for the total synthesis of blepharismins and oxyblepharismins. Furthermore, it could shed some light on the biogenesis of these photosensing pigments. Irradiation of 3,4-di-O-benzyl hypericin in benzene solution together with a large excess of 1,8-bis-(dimethylamino)-naphthalene produced a species exhibiting a tremendous absorption band in the near IR. By means of EPR spectroscopy it could be stated that this primary photoproduct was of radical nature. The product was examined by means of UV/VIS, NMR, IR and mass spectroscopy. (author)

  17. Comparison of nitrogen fixation in some Bradyrhizobium Japonicum strains using the N-15 isotopic method

    International Nuclear Information System (INIS)

    Several studies have demonstrated the significant contribution of atmospheric N fixation to soybean nutrition and growth. The variability in N fixing is due to the several factors including rhizobial strain. Hence, this study was conducted to compare some commercial Bradyrhizobium japonicum strains for the amount and proportion of N fixation in soybean (Cv. Williams) which is most commonly cultivated in Iran. Initially, strains were tested for purity, infectiveness and symbiotic effectiveness using Leonard jars and three of the more efficient strains Helinitro, Rhizoking and Gold Coat were selected. A pot experiment (four replicated) was carried out with RCBD on soil without indigenous rhizobia having 530-ppm total nitrogen under greenhouse condition. Treatments included three inoculum of selected strains (separately) and a set of non inoculated blank. For estimating BNF by A-value method, two solutions of N-15 enriched ammonium sulfate, containing 9.616 and 2.086% n-15 atom excess, were applied in amount of 20 and 100 kg N/ha at stage V2 in inoculated pots and stages V2, R2 and R5 to reference pots. During the 4 months of growth, plants were irrigated with distilled water to maintain 80% FC. Plants were harvested at stage R6. The results showed that the effects of rhizobial strains were significantly different. Gold Coat and Rhizoking strains had higher significant results compared with Helinitro. The percentages of fixed nitrogen in plants inoculated with these strains were 92.3, 90.7 and 84.7%, respectively. On the basis of these results, it may be necessary to pre-select more compatible rhizobial strain for supplying the N-requirements of soybean. (Author)

  18. Course of Schistosoma mansoni infection in thymectomized rats. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Cioli, D.; Dennert, G.

    1976-07-01

    Inbred rats were thymectomized, irradiated, and reconstituted with T cell-free bone marrow cells. Thymectomized-reconstituted (B rats) and control rats were infected with Schistosoma mansoni cercariae and the number of worms recovered was determined at various times after infection. The extent of immunosuppression was assessed by two criteria: response to an injection of sheep erythrocytes; response to schistosome antigens. Humoral responses to worm antigens were completely suppressed in almost all instances and anti-sheep erythrocytes responses showed a more variable but always very definite depression in B rats. The number of worms in B rats was about 4 times higher than in control animals at 5 weeks and about 3 times higher at 6 weeks. In a different experiment, rats were perfused at 4, 6, and 9 weeks after infection and the number of worms was found to be consistently higher in B rats, by a factor of about 2 at 4 weeks to a factor of about 4 or 6 at subsequent times. Although B rats had more worms than controls even at 9 weeks, a slow drop in their worm burden was noticeable with time in both experiments. Moreover, the size of worms in B rats was smaller than in controls and even 9-week-old worms failed to develop to normal size and appearance and could not be shown to produce fertile eggs. These experiments show a definite involvement of the immune system in the ''self-cure'' phenomenon, but may at the same time suggest that other non-immune mechanisms are involved in determining the pattern of S. mansoni infection in the rat.

  19. Course of Schistosoma mansoni infection in thymectomized rats

    International Nuclear Information System (INIS)

    Inbred rats were thymectomized, irradiated, and reconstituted with T cell-free bone marrow cells. Thymectomized-reconstituted (B rats) and control rats were infected with Schistosoma mansoni cercariae and the number of worms recovered was determined at various times after infection. The extent of immunosuppression was assessed by two criteria: response to an injection of sheep erythrocytes; response to schistosome antigens. Humoral responses to worm antigens were completely suppressed in almost all instances and anti-sheep erythrocytes responses showed a more variable but always very definite depression in B rats. The number of worms in B rats was about 4 times higher than in control animals at 5 weeks and about 3 times higher at 6 weeks. In a different experiment, rats were perfused at 4, 6, and 9 weeks after infection and the number of worms was found to be consistently higher in B rats, by a factor of about 2 at 4 weeks to a factor of about 4 or 6 at subsequent times. Although B rats had more worms than controls even at 9 weeks, a slow drop in their worm burden was noticeable with time in both experiments. Moreover, the size of worms in B rats was smaller than in controls and even 9-week-old worms failed to develop to normal size and appearance and could not be shown to produce fertile eggs. These experiments show a definite involvement of the immune system in the ''self-cure'' phenomenon, but may at the same time suggest that other non-immune mechanisms are involved in determining the pattern of S. mansoni infection in the rat

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

    Czech Academy of Sciences Publication Activity Database

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

    2015-01-01

    Roč. 16, NOV 19 2015 (2015), s. 980. ISSN 1471-2164 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Schistosoma mansoni * glucose transporters * transcriptional regulation * phylogen * biophysics Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.986, year: 2014

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

    International Nuclear Information System (INIS)

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

  2. 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...

  3. Evaluation of the molluscicidal and Schistosoma mansoni cercariae activity of Croton floribundus extracts and kaurenoic acid

    OpenAIRE

    Janaina M. Medina; Juliana L. B. Peixoto; Silva, Adriano A.; Shirani K. Haraguchi; Dina L. M. Falavigna; Maria L. M. Zamuner; Maria H. Sarragiotto; Vidotti, Gentil J.

    2009-01-01

    Lethality of the extracts of Croton floribundus (Euphorbiaceae), a medicinal plant from south Brazil, and of the kaurenoic acid, an isolated compound, and two of its derivatives against adult Biomphalaria glabrata snails, Schistosoma mansoni cercariae and Artemia salina Leach. brine shrimp larvae are reported. Both extracts and the isolated compound showed significant molluscicidal and cercaricidal activities and reduced toxicity in brine shrimp assays.

  4. Techniques for locating isotopically labelled schistosomula of Schistosoma mansoni in host tissued for ultrastructural investigations

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, J.E.; Wilson, R.A.

    1986-03-01

    The use of /sup 75/Selenomethionine labelled cercariae of Schistosoma mansoni for ultrastructural localization of resin-embedded tissue were successful. The autoradiographic technique was more sensitive and schistosomula were readily located in pulmonary tissue up to 24 days post infection.

  5. Immunization of baboons with Schistosoma mansoni cercariae attenuated by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Stek, M. Jr.; Minard, P.; Dean, D.A.; Hall, J.E.

    1981-06-26

    Studies on the efficacy of a vaccine against schistosomiasis in young baboons (Papio anubis) disclosed that immunization with Schistosoma mansoni cercariae attenuated by gamma irradiation induced significant protection against subsequent infection with normal, viable S. mansoni cercariae. Such immunization resulted in reduced worm burdens (70%) and egg excretion rates (82%). These results support immunization as a potential method for schistosomiasis control.

  6. Immunization of Baboons with Schistosoma mansoni Cercariae attenuated by gamma irradiation

    International Nuclear Information System (INIS)

    Studies on the efficacy of a vaccine against schistosomiasis in young baboons (Papio anubis) disclosed that immunization with Schistosoma mansoni cercariae attenuated by gamma irradiation induced significant protection against subsequent infection with normal, viable S. mansoni cercariae. Such immunization resulted in reduced worm burdens (70 percent) and egg excretion rates (82 percent). These results support immunization as a potential method for schistosomiasis control

  7. Immunization of baboons with Schistosoma mansoni cercariae attenuated by gamma irradiation

    International Nuclear Information System (INIS)

    Studies on the efficacy of a vaccine against schistosomiasis in young baboons (Papio anubis) disclosed that immunization with Schistosoma mansoni cercariae attenuated by gamma irradiation induced significant protection against subsequent infection with normal, viable S. mansoni cercariae. Such immunization resulted in reduced worm burdens (70%) and egg excretion rates (82%). These results support immunization as a potential method for schistosomiasis control

  8. Immunization of Baboons with Schistosoma mansoni Cercariae attenuated by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Stek, M.; Minard, P.; Dean, D.A.; Hall, J.E.

    1981-06-01

    Studies on the efficacy of a vaccine against schistosomiasis in young baboons (Papio anubis) disclosed that immunization with Schistosoma mansoni cercariae attenuated by gamma irradiation induced significant protection against subsequent infection with normal, viable S. mansoni cercariae. Such immunization resulted in reduced worm burdens (70 percent) and egg excretion rates (82 percent). These results support immunization as a potential method for schistosomiasis control.

  9. Techniques for locating isotopically labelled schistosomula of Schistosoma mansoni in host tissued for ultrastructural investigations

    International Nuclear Information System (INIS)

    The use of 75Selenomethionine labelled cercariae of Schistosoma mansoni for ultrastructural localization of resin-embedded tissue were successful. The autoradiographic technique was more sensitive and schistosomula were readily located in pulmonary tissue up to 24 days post infection. (author)

  10. Identification of G protein-coupled receptors in Schistosoma haematobium and S. mansoni by comparative genomics

    OpenAIRE

    Campos, Tulio D L; Young, Neil D.; Korhonen, Pasi K.; Hall, Ross S.; Mangiola, Stefano; Lonie, Andrew; Gasser, Robin B

    2014-01-01

    Background Schistosomiasis is a parasitic disease affecting ~200 million people worldwide. Schistosoma haematobium and S. mansoni are two relatively closely related schistosomes (blood flukes), and the causative agents of urogenital and hepatointestinal schistosomiasis, respectively. The availability of genomic, transcriptomic and proteomic data sets for these two schistosomes now provides unprecedented opportunities to explore their biology, host interactions and schistosomiasis at the molec...

  11. 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...

  12. Activation route of the Schistosoma mansoni cathepsin B1 drug target

    Czech Academy of Sciences Publication Activity Database

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

    2015-01-01

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

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

    DEFF Research Database (Denmark)

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

    2005-01-01

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

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  15. Myeloradicular Form of Neuroschistosomiasis in a Six-Year-Old Boy Infected With Schistosoma mansoni.

    Science.gov (United States)

    Salgado, João Victor; Salgado, Izabel Athayde da Silva Cruz; Braga Júnior, Leônidas Lopes; Serra, Silane Calland Marques; Barros, Verbena Maria de Carvalho; Silva, Maria José Alves; Monteiro-Neto, Valério

    2015-12-01

    Neuroschistosomiasis is a severe disease caused by the presence of Schistosoma eggs and/or adult worms in the central nervous system. Schistosomal transverse myelitis represents a rare clinical form with nonspecific clinical findings, and it is thus underdiagnosed, especially in children. In this report, we describe a 6-year-old patient with the myeloradicular form of neuroschistosomiasis. PMID:26780026

  16. Impact of natural and anthropogenic factors on the trophic interactions of molluscivores and Schistosoma host snails

    NARCIS (Netherlands)

    Monde, C.

    2016-01-01

    Summary With a global disease burden of 240 million infected people, of which 90% live in sub-Saharan Africa, schistosomiasis is one of the most prevalent Neglected Tropical Diseases affecting people in the tropical and sub-tropical regions of the world. Schistosoma parasites are th

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

    Directory of Open Access Journals (Sweden)

    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

  18. Cloning, Sequencing and Characterization of 3-Hydroxybuty- rate Dehydrogenase Encoding Gene (bdh A) in Bradyrhizobium japonicum USDA110 Strain

    Institute of Scientific and Technical Information of China (English)

    DAI Mei-xue; WU Bo; BAI Xue-liang; ZHANG Cheng-gang; MA Qing-sheng; Charles Trevor C

    2002-01-01

    The current study describes the molecular characterization of a clone which can restore the ability of bdhA mutant strains NGRPA2 and Rm11107 to utilize 3-hydroxybutyrate as a sole carbon source (Hbu+). This clone was screened out by complementation experiment from Bradyrhizobium japonicum USDA110 genomic library, and the presence of bdhA gene in the clone was verified by Bdh assay and Southern blot analysis. Furthermore, the entire sequence of bdhA gene was sequenced and the sequence was deposited in GenBank database under the accession number AY077581. bdhA gene comprises 789 base pairs and encodes Bdh with 262 amino acid of MW 27.59 kDa. Interposon ΩKm was inserted into the bdh A ORF at EcoR I site and the bdhA mutant was constructed in B .japonicum by homologous recombination. Plant assay result did not show obvious effects of mutation of bdhA gene on nodulation and nitrogen-fixation.

  19. An L-glucitol oxidizing dehydrogenase from Bradyrhizobium japonicum USDA 110 for production of D-sorbose with enzymatic or electrochemical cofactor regeneration

    DEFF Research Database (Denmark)

    Gauer, Sabrina; Wang, Zhijie; Otten, Harm; Etienne, Mathieu; Bjerrum, Morten Jannik; Lo Leggio, Leila; Walcarius, Alain; Giffhorn, Friedrich; Kohring, Gert-Wieland

    2014-01-01

    A gene in Bradyrhizobium japonicum USDA 110, annotated as a ribitol dehydrogenase (RDH), had 87 % sequence identity (97 % positives) to the N-terminal 31 amino acids of an L-glucitol dehydrogenase from Stenotrophomonas maltophilia DSMZ 14322. The 729-bp long RDH gene coded for a protein consisting...

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

    Directory of Open Access Journals (Sweden)

    Tânia Maria Correa Silva

    1989-06-01

    Full Text Available 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 deposição maior de ovos se faz a nível do intestino, sobretudo do jejuno, com passagem de grande número de ovos para as fezes. Miracídios isolados a partir dos ovos retirados dos roedores infectaram normalmente a Biomphalaria glabrata, com eliminação de cercárias, com as quais se provocou infecção no camundongo branco, em tudo semelhante aquelas causadas por outras cepas de origem humana. Também camundongos que foram deixados em contacto com as águas infestadas pelos roedores silvestres se infectaram facilmente, atestando o alto grau de transmissibilidade da área. Conclui-se que os roedores silvestres de planalto toleram bem a infecção esquistossomótica natural, são bons eliminadores de ovos viáveis do S. mansoni, estão infectados por uma cepa semelhante a que infecta o homem e podem ter um papel na manutenção do ciclo vital do S. mansoni na área estudada.In Planalto, a small locality in the interior of the Bahia state, Brazil, 47% of sylvatic rodents were found to be naturally infected with Schistosoma mansoni, whereas the prevalence of the infection in the inhabitants of the area was 3.26%. The rodents (Nectomys live near the houses, in contact with water passing viable schistosome eggs in the stools. Worm burden is variable amongst such rodents. Periovular granulomas are small, especially in liver and intestines, and hepatic fibrosis is mild or absent, with no morphological evidence of portal hypertension being noted

  1. Relationship of Impairment of Schistosome 28-Kilodalton Glutathione S-Transferase (GST) Activity to Expression of Immunity to Schistosoma mattheei in Calves Vaccinated with Recombinant Schistosoma bovis 28-Kilodalton GST

    OpenAIRE

    Grzych, Jean-Marie; De Bont, Jan; Liu, Jinli; Neyrinck, Jean-Loup; Fontaine, Josette; Vercruysse, Jozef; Capron, André

    1998-01-01

    Sera from calves vaccinated with the recombinant Schistosoma bovis-derived 28-kDa glutathione S-transferase (28GST) and subsequently naturally or experimentally exposed to Schistosoma mattheei were studied for their content of specific immunoglobulin G (IgG) and IgA antibodies to recombinant S. bovis 28GST as well as for their capacity to inhibit the enzymatic activity of the antigen. The results were analyzed in regard to the presence (natural infection) or absence (experimental infection) o...

  2. Block clustering with collapsed latent block models

    OpenAIRE

    Wyse, Jason; Friel, Nial

    2010-01-01

    We introduce a Bayesian extension of the latent block model for model-based block clustering of data matrices. Our approach considers a block model where block parameters may be integrated out. The result is a posterior defined over the number of clusters in rows and columns and cluster memberships. The number of row and column clusters need not be known in advance as these are sampled along with cluster memberhips using Markov chain Monte Carlo. This differs from existing work on latent bloc...

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Incomplete block designs

    CERN Document Server

    Dey, Aloke

    2010-01-01

    This book presents a systematic, rigorous and comprehensive account of the theory and applications of incomplete block designs. All major aspects of incomplete block designs are considered by consolidating vast amounts of material from the literature - the classical incomplete block designs, like the balanced incomplete block (BIB) and partially balanced incomplete block (PBIB) designs. Other developments like efficiency-balanced designs, nested designs, robust designs, C-designs and alpha designs are also discussed, along with more recent developments in incomplete block designs for special t

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

    Directory of Open Access Journals (Sweden)

    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

  6. Postural heart block.

    OpenAIRE

    Seda, P E; McAnulty, J H; Anderson, C J

    1980-01-01

    A patient presented with orthostatic dizziness and syncope caused by postural heart block. When the patient was supine, atrioventricular conduction was normal and he was asymptomatic; when he was standing he developed second degree type II block and symptoms. The left bundle-branch block on his electrocardiogram and intracardiac electrophysiological study findings suggest that this heart block occurred distal to the His bundle. Orthostatic symptoms are usually presumed to be secondary to an i...

  7. Polimorfismo de tallas en las cercarias de una cepa venezolana de Schistosoma mansoni Polymorphism of size in the cercariae of one venezuelan strain of Schistosoma mansoni

    OpenAIRE

    Luz A. Pino; Liboria Matinella; Gustavo Morales

    1999-01-01

    Mediante la impregnación con nitrato de plata, de un lote de 47 cercarias de la cepa C5 de Schistosoma mansoni (Venezuela), se evidenció un polimorfismo de tallas. El morfo estaría conformado por las cercarias mas grandes (entre 152,9 y 218µm), este grupo siempre presente en la población de cercarias en menor porcentaje (29,8%). El grupo constituido por las cercarias de talla normal, menores de 152,8µm es dominante en la población de cercarias (70,2%). La comparación entre el largo de ambos l...

  8. Catabolism of indole-3-acetic acid and 4- and 5-chloroindole-3-acetic acid in Bradyrhizobium japonicum

    DEFF Research Database (Denmark)

    Jensen, J B; Egsgaard, H; Van Onckelen, H;

    1995-01-01

    Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid...... chromatography and conventional mass spectrometry (MS) methods, including MS-mass spectroscopy, UV spectroscopy, and high-performance liquid chromatography-MS. The identified products indicate a novel metabolic pathway in which IAA is metabolized via dioxindole-3-acetic acid, dioxindole, isatin, and 2......-aminophenyl glyoxylic acid (isatinic acid) to anthranilic acid, which is further metabolized. Degradation of 4-Cl-IAA apparently stops at the 4-Cl-dioxindole step in contrast to 5-Cl-IAA which is metabolized to 5-Cl-anthranilic acid. Udgivelsesdato: 1995-Oct...

  9. Homology modeling and docking studies of BjGL, a novel (+) gamma-lactamase from Bradyrhizobium japonicum.

    Science.gov (United States)

    Song, Dawei; Zhu, Shaozhou; Li, Xingzhou; Zheng, Guojun

    2014-02-01

    (+) Gamma-lactamases are enantioselective hydrolysis enzymes that can be used to produce optically pure (-) gamma-lactam, an important pharmaceutical intermediate for the anti-AIDS drug Abacavir. In this study, homology modeling and molecular dynamic simulation studies of a 3D homology model of BjGL, a novel (+) gamma-lactamase from Bradyrhizobium japonicum, were constructed and refined. The specific substrate (+) gamma-lactam and its enantiomer (-) gamma-lactam which can not be hydrolyzed was docked into the active site respectively, and the catalytic triad and other crucial residues that participate in the formation of the hydrophobic binding pocket, hydrogen bonds, and the oxyanion hole were identified. Furthermore, possible reasons for the high diastereoselectivity of BjGL binding with the substrate are proposed. PMID:24215997

  10. Influence of nitrogen and Bradyrhizobium japonicum on the growth of late maturing soybean by using 15N method

    International Nuclear Information System (INIS)

    The successful of symbiosis between soybean and rhizobia is only possible under favorable soil condition. Only then biological N2 fixation may occur. The objective of this study was to determine the effect of N-fertilizer and Bradyrhizobium japonicum on the growth and yield of late maturing soybean by using 15N. The experiment was conducted at the Department of Agronomy at Bogor in an Inceptisol from Darmaga. Due to high level of Mn-exchangeable resulted from gamma radiation to sterilize the soil, nodulation failed totality. Soybean plant showed chlorosis and Mn toxicity symptoms. Soybean were only affected by N-fertilizer levels. 90 kg ha-1, which at this rate gave the highest shoot and root weights, but tended to lower in total N of plant than 0,45 kg and 135 kg N/ha, respectively. The higher nitrogen fertilizer dose , the higher uptake nitrogen derived from fertilizer. Seed were not formed. (author)

  11. Fluorescence studies with malate dehydrogenase from rhizobium japonicum 3I1B-143 bacteroids: a two-tryptophan containing protein

    Science.gov (United States)

    Ghiron, Camillo A.; Eftink, Maurice R.; Waters, James K.; Emerich, David W.

    1990-05-01

    A number of fluorescence studies, both of trp residues and bound NADH, have been reported for porcine MDH. The large number of trp residues (6) complicates the interpretation of some studies. To circumvent this we have performed studies with a two tryptophan (per subunit) MDH from Rhizobium japonicum 311B-143 bacteroids. We have performed phase/modulation fluorescence lifetime measurements, as a function of temperature and added quencher KI, in order to resolved the 1.3 ns (blue) and 6.6 ns (red) contributions from the two classes of trp residues. Anisotropy decay studies have also been performed. The binding of NADH dynamically quenches the fluorescence of both tip residues, but, unlike mammalian cytoplasmic and mitochondrial MDH, there is not a large enhancement in fluorescence of bound NADH upon forming a ternary complex with either tartronic acid or D-malonate.

  12. High Throughput Screening Identifies Novel Lead Compounds with Activity against Larval, Juvenile and Adult Schistosoma mansoni.

    Science.gov (United States)

    Mansour, Nuha R; Paveley, Ross; Gardner, J Mark F; Bell, Andrew S; Parkinson, Tanya; Bickle, Quentin

    2016-04-01

    An estimated 600 million people are affected by the helminth disease schistosomiasis caused by parasites of the genus Schistosoma. There is currently only one drug recommended for treating schistosomiasis, praziquantel (PZQ), which is effective against adult worms but not against the juvenile stage. In an attempt to identify improved drugs for treating the disease, we have carried out high throughput screening of a number of small molecule libraries with the aim of identifying lead compounds with balanced activity against all life stages of Schistosoma. A total of almost 300,000 compounds were screened using a high throughput assay based on motility of worm larvae and image analysis of assay plates. Hits were screened against juvenile and adult worms to identify broadly active compounds and against a mammalian cell line to assess cytotoxicity. A number of compounds were identified as promising leads for further chemical optimization. PMID:27128493

  13. Evaluation of symbiotic performance of some mutant lines of soybean inoculated with two bradyrhizobium japonicum strains using 15N technique

    International Nuclear Information System (INIS)

    A pot experiment was conducted to study the symbiotic performance of two soybean varieties and some of their mutants (that were obtained as a result of a previous mutation breeding program) with two bradyrhizobium japonicum strains (RG and FA3) using 15N isotopic dilution method. Random amplified polymorphic DNA technique (RAPD) was used to study the genetic relationships among the soybean genotypes and to make sure that the two rhizobial strains are different. The 25 random primers used discriminated the different soybean genotypes and the dendrogram resultants from shared polymorphic fragments put each variety and its mutants in two separate clusters asserting that the mutants and their mother lines are different. Both strains of B. japonicum were able to form effective nodules on all soybean plants. However, number of nodules, dry matter yield and N-uptake from the available sources by soybeans were affected by both plant genotype and rhizobial strains. N2-fixation was affected to a large extent by different strain and plant genotype combinations. Percentage of fixed N2 (N dfa) ranged between 35 and 49%; whereas, the actual amounts of fixed N2 were between 105 and 210 mg N/pot. Amounts of N2-fixed by FA3 strain were higher than of RG in both soybean varieties, whereas, the latter strain showed higher performance in the mutant lines. The results showed that total plant N estimation may not be a sufficient indicator for high N2-fixation. the results also showed that it is very important to determine both the amount of nitrogen derived from N2-fixation and N derived from soil for evaluating the symbiotic performance ability. Moreover, the performance of symbiotic N2-fixation in soybean was shown to depend on both plant genotype and rhizobial strain and the amount of N2-fixation can be increased by combining the best plant genotypes and the most adapted strain. (author)

  14. Identification and functional characterization of soybean root hair microRNAs expressed in response to Bradyrhizobium japonicum infection.

    Science.gov (United States)

    Yan, Zhe; Hossain, Md Shakhawat; Valdés-López, Oswaldo; Hoang, Nhung T; Zhai, Jixian; Wang, Jun; Libault, Marc; Brechenmacher, Laurent; Findley, Seth; Joshi, Trupti; Qiu, Lijuan; Sherrier, D Janine; Ji, Tieming; Meyers, Blake C; Xu, Dong; Stacey, Gary

    2016-01-01

    Three soybean [Glycine max (L) Merr.] small RNA libraries were generated and sequenced using the Illumina platform to examine the role of miRNAs during soybean nodulation. The small RNA libraries were derived from root hairs inoculated with Bradyrhizobium japonicum (In_RH) or mock-inoculated with water (Un_RH), as well as from the comparable inoculated stripped root samples (i.e. inoculated roots with the root hairs removed). Sequencing of these libraries identified a total of 114 miRNAs, including 22 novel miRNAs. A comparison of miRNA abundance among the 114 miRNAs identified 66 miRNAs that were differentially expressed between root hairs and stripped roots, and 48 miRNAs that were differentially regulated in infected root hairs in response to B. japonicum when compared to uninfected root hairs (P ≤ 0.05). A parallel analysis of RNA ends (PARE) library was constructed and sequenced to reveal a total of 405 soybean miRNA targets, with most predicted to encode transcription factors or proteins involved in protein modification, protein degradation and hormone pathways. The roles of gma-miR4416 and gma-miR2606b during nodulation were further analysed. Ectopic expression of these two miRNAs in soybean roots resulted in significant changes in nodule numbers. miRNA target information suggested that gma-miR2606b regulates a Mannosyl-oligosaccharide 1, 2-alpha-mannosidase gene, while gma-miR4416 regulates the expression of a rhizobium-induced peroxidase 1 (RIP1)-like peroxidase gene, GmRIP1, during nodulation. PMID:25973713

  15. STUDY ON PROTECTION AGAINST SCHISTOSOMA JAPONICUM INDUCED BYPASSIVELY TRANSFERED SERA FROM MICROTUS FOTIS IN THE MOUSE%东方田鼠血清被动转移抗日本血吸虫的保护力研究

    Institute of Scientific and Technical Information of China (English)

    蒋守富; 魏梅雄; 林矫矫; 潘彩娥; 李浩; 曹琳; 何艳燕; 傅志强

    2004-01-01

    目的探讨被动转移东方田鼠血清抗日本血吸虫感染力及其作用机理. 方法将东方田鼠血清通过尾静脉注射途径被动转移至小鼠,观察攻击感染日本血吸虫尾蚴后的减虫率、减卵率,并采用ELISA分别检测抗日本血吸虫童虫、成虫和虫卵的8种抗体. 结果与生理盐水对照组比较, 东方田鼠血清受体小鼠获得的减虫率为36.2%,减卵率为54.0%;血清IgE、IgM、IgG及其亚类抗体均有升高,其中抗童虫抗原的IgG1抗体水平增幅最大.各试验组小鼠血清抗体水平差异均无显著性(P>0.05). 结论东方田鼠抗日本血吸虫感染的天然抵抗力可通过血清被动转移至小鼠,使之获得部分抗血吸虫感染的保护力,该保护力可能是通过同时诱导受体小鼠Th1和Th2型免疫应答发挥作用的.

  16. EFFECT OF pH ON THE MUTAGENIC POTENCY OF ICR-170 IN THE REPRODUCTIVE GLANDS OF FEMALE SCHISTOSOMA JAPONICUM%PH对ICR-170诱变日本血吸虫雌虫生殖腺的影响

    Institute of Scientific and Technical Information of China (English)

    蒋守富; 潘彩娥; 陆钦淹

    2003-01-01

    目的探讨溶液pH对诱变剂ICR-170诱变日本血吸虫雌虫生殖腺的影响程度.方法用5种pH值(pH 7.2-8.0)的ICR-170溶液处理日本血吸虫尾蚴30 min或45 min后,经皮肤接种小鼠观察雌虫诱变率和成虫回收率.结果溶液pH值对ICR-170的诱变作用影响较大,诱变率随着溶液pH值的上升而下降.10μg/ml 45 min组和15μg/ml 30 min组在pH 7.2时的雌虫诱变率分别为pH 7.8时的13倍和6倍,当pH>7.4时,2种浓度的ICR-170引起的诱变率基本接近.溶液pH值对于成虫回收率的影响程度远低于对诱变率的影响程度.结论在诱变日本血吸虫雌虫生殖腺时,ICR-170具有较强的pH依赖型特性.

  17. Homology modeling and SAR analysis of Schistosoma japonicum cathepsin D (SjCD) with statin inhibitors identify a unique active site steric barrier with potential for the design of specific inhibitors

    Czech Academy of Sciences Publication Activity Database

    Caffrey, C. R.; Plachá, L.; Bařinka, Cyril; Hradilek, Martin; Dostál, Jiří; Sajid, M.; McKerrow, J. H.; Majer, P.; Konvalinka, Jan; Vondrášek, Jiří

    2005-01-01

    Roč. 386, č. 4 (2005), 339-349. ISSN 1431-6730 R&D Projects: GA MŠk(CZ) LC512; GA ČR(CZ) GP203/02/P095; GA AV ČR(CZ) IAA400550510 Grant ostatní: SFSF(US) AI 53247; NATO(XE) CLG 974914 Institutional research plan: CEZ:AV0Z4055905 Keywords : schistotoma * proteases of parasites * modelling Subject RIV: CE - Biochemistry Impact factor: 2.577, year: 2005

  18. Impact of natural and anthropogenic factors on the trophic interactions of molluscivores and Schistosoma host snails

    OpenAIRE

    Monde, C.

    2016-01-01

    Summary With a global disease burden of 240 million infected people, of which 90% live in sub-Saharan Africa, schistosomiasis is one of the most prevalent Neglected Tropical Diseases affecting people in the tropical and sub-tropical regions of the world. Schistosoma parasites are the causative agents of schistosomiasis. They complete their asexual life stages in susceptible aquatic snails while the sexual stages are completed in susceptible mammals including man. Control of this disease is ta...

  19. 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 ...

  20. Efficacy of niclosamide as a potential antipenetrant (TAP) against cercariae of Schistosoma mansoni monkeys

    OpenAIRE

    John I. Bruce; Robert Miller; Lawrence Lightner; Subbiah Yoganathan

    1992-01-01

    A 1% (W/V) formulation of Niclosamide (2', 5-Dichloro-4-nitrosalicylanilide) (TAP) was tested on Cebus apella monkeys as a topical prophylatic against schistosomiasis mansoni. Two experiments were conducted using the same formulation. In the first experiment, the TAP provided complete protection against schistosomiasis for 3 days. Of the 4 monkeys treated with TAP 7 days before exposure to Schistosoma mansoni cercariae, 2 were completely protected. The remaining 2 monkeys of the 7 day treatme...

  1. Genetic Population Structure of Cercariae from an Urban Foci of Schistosoma mansoni, Brazil

    OpenAIRE

    Souza, Samaly S.; Lúcio M Barbosa; Guimarães, Isabel C.; Blank, Walter A.; Reis, Renato Barbosa; Reis, Mitermayer G; Blanton, Ronald E.; Zilton A. Andrade

    2012-01-01

    Rapid urbanization in Brazil has meant that many persons from rural areas where Schistosoma mansoni is endemic have migrated to cities. Discovery of a focus of active transmission in the city of Salvador prompted a citywide survey for active and potential transmission sites. Cercariae shed from infected snails collected from four locations were used to determine how these samples were related and if they were representative of the parasite population infecting humans. Each cercarial collectio...

  2. Effects of exogenous glucose on survival and infectivity of Schistosoma mansoni cercariae

    OpenAIRE

    Fried, Bernard; Laterra, Robert; KIM, YONGHYUN

    2002-01-01

    The effects of exogenous glucose in artificial spring water (ASW) were studied on the survival and infectivity of Schistosoma mansoni cercariae. The mean percent survival of cercariae maintained in 1% glucose in ASW for 36 and 48hr was significantly greater than that of cercariae maintained identically in ASW. Cercariae maintained in ASW with or without glucose for 24hr, fixed in neutral buffered formalin, and stained in Oil Red O, showed an accumulation of neutral lipid in the tail. Cercaria...

  3. Immunization of mice with ultraviolet-irradiated Schistosoma mansoni cercariae: a re-evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Dean, D.A.; Murrell, K.D.; Xu, S.; Mangold, B.L.

    1983-07-01

    Mice immunized by percutaneous exposure to ultraviolet-irradiated Schistosoma mansoni cercariae developed levels of resistance to subsequent S. mansoni infection comparable to those induced by gamma-irradiated cercariae (50-70% reduction in adult worm burden). Cercariae treated with ultraviolet doses ranging from one to three times the minimum dose required to prevent long-term survival induced the highest levels of resistance.

  4. Sensory Protein Kinase Signaling in Schistosoma mansoni Cercariae: Host Location and Invasion

    OpenAIRE

    Ressurreição, Margarida; Kirk, Ruth S; Rollinson, David; Emery, Aidan M.; Page, Nigel M.; Walker, Anthony J.

    2015-01-01

    Schistosoma mansoni cercariae display specific behavioral responses to abiotic/biotic stimuli enabling them to locate and infect the definitive human host. Here we report the effect of such stimulants on signaling pathways of cercariae in relation to host finding and invasion. Cercariae exposed to various light/temperature regimens displayed modulated protein kinase C (PKC), extracellular signal–regulated kinase (ERK) and p38 mitogen-activated protein kinase (p38 MAPK) activities, with distin...

  5. Sequential histological changes in Biomphalaria glabrata during the course of Schistosoma mansoni infection

    OpenAIRE

    2001-01-01

    Biomphalaria glabrata, highly susceptible to Schistosoma mansoni, were seen to shed less and less cercariae along the time of infection. Histological examination kept a close correlation with this changing pattern of cercarial shedding, turning an initial picture of no-reaction (tolerance) gradually into one of hemocyte proliferation with formation of focal encapsulating lesions around disintegrating sporocysts and cercariae, a change that became disseminated toward the 142nd day post miracid...

  6. Immunization of mice with ultraviolet-irradiated Schistosoma mansoni cercariae: a re-evaluation

    International Nuclear Information System (INIS)

    Mice immunized by percutaneous exposure to ultraviolet-irradiated Schistosoma mansoni cercariae developed levels of resistance to subsequent S. mansoni infection comparable to those induced by gamma-irradiated cercariae (50-70% reduction in adult worm burden). Cercariae treated with ultraviolet doses ranging from one to three times the minimum dose required to prevent long-term survival induced the highest levels of resistance

  7. Two heat-induced proteins are associated with transformation of Schistosoma mansoni cercariae to schistosomula.

    OpenAIRE

    Blanton, R; Loula, E C; Parker, J.

    1987-01-01

    Infection with Schistosoma mansoni, a parasitic fluke, is acquired when cercariae found in freshwater bodies at ambient temperature penetrate human skin. In this study the response of S. mansoni cercariae to change in temperature from ambient to that of mammalian hosts was compared to the response of other stages that do not experience such dramatic temperature shifts. In cercariae, temperature increases from 23 degrees C to either 37 degrees C or 42 degrees C primarily induced the synthesis ...

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

    Czech Academy of Sciences Publication Activity Database

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

    2011-01-01

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

  9. Elimination of Schistosoma mansoni Adult Worms by Rhesus Macaques: Basis for a Therapeutic Vaccine?

    OpenAIRE

    Wilson, R. Alan; Langermans, Jan A. M.; van Dam, Govert J.; Vervenne, Richard A.; Hall, Stephanie L.; Borges, William C.; Dillon, Gary P.; Thomas, Alan W.; Patricia S Coulson

    2008-01-01

    Background Among animal models of schistosomiasis, the rhesus macaque is unique in that an infection establishes but egg excretion rapidly diminishes, potentially due to loss of adult worms from the portal system via shunts or death by immune attack. Principal Findings To investigate this, six rhesus macaques were exposed to Schistosoma mansoni cercariae and the infection monitored until portal perfusion at 18 weeks. Despite a wide variation in worm numbers recovered, fecal egg output and cir...

  10. 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...

  11. 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...

  12. 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 ...

  13. Mechanism of Anemia in Schistosoma mansoni–Infected School Children in Western Kenya

    OpenAIRE

    Butler, Sara E.; Muok, Erick M.; Montgomery, Susan P.; Odhiambo, Keziah; Mwinzi, Pauline M. N.; Secor, W. Evan; Karanja, Diana M. S.

    2012-01-01

    A better understanding of the mechanism of anemia associated with Schistosoma mansoni infection might provide useful information on how treatment programs are implemented to minimize schistosomiasis-associated morbidity and maximize treatment impact. We used a cross-sectional study with serum samples from 206 Kenyan school children to determine the mechanisms in S. mansoni-associated anemia. Serum ferritin and soluble transferrin receptor levels were measured by using an enzyme-linked immunos...

  14. 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 ...

  15. Diagnostic of Biomphalaria snails and Schistosoma mansoni: DNA obtained from traces of shell organic materials

    OpenAIRE

    Roberta L Caldeira; Liana K. Jannotti-Passos; Pollanah M Lira; Omar S Carvalho

    2004-01-01

    Freshwater snails belonging to the genus Biomphalaria act as intermediate hosts for the parasite trematode Schistosoma mansoni in Africa and in the neotropical region. Identification of such molluscs is carried out based on morphological characters and the presence of cercariae is verified through squeezing snails between two glass slides or by exposing them to artificial light. However, sometimes, the material collected includes molluscs with decomposed bodies or, yet, only empty shells, whi...

  16. Evidence against rapid emergence of praziquantel resistance in Schistosoma haematobium, Kenya.

    OpenAIRE

    Coles, G. C.; Liang, Y S; M. J. Doenhoff

    2000-01-01

    We examined the long-term efficacy of praziquantel against Schistosoma haematobium, the causative agent of urinary schistosomiasis, during a school-based treatment program in the Msambweni area of Coast Province, Kenya, where the disease is highly endemic. Our results, derived from treating 4,031 of 7,641 children from 1984 to 1993, indicate substantial year-to- year variation in drug efficacy. However, the pattern of this variation was not consistent with primary or progressive emergence of ...

  17. 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...

  18. Analysis of regulatory protease sequences identified through bioinformatic data mining of the Schistosoma mansoni genome

    Directory of Open Access Journals (Sweden)

    Minchella Dennis J

    2009-10-01

    Full Text Available Abstract Background New chemotherapeutic agents against Schistosoma mansoni, an etiological agent of human schistosomiasis, are a priority due to the emerging drug resistance and the inability of current drug treatments to prevent reinfection. Proteases have been under scrutiny as targets of immunological or chemotherapeutic anti-Schistosoma agents because of their vital role in many stages of the parasitic life cycle. Function has been established for only a handful of identified S. mansoni proteases, and the vast majority of these are the digestive proteases; very few of the conserved classes of regulatory proteases have been identified from Schistosoma species, despite their vital role in numerous cellular processes. To that end, we identified protease protein coding genes from the S. mansoni genome project and EST library. Results We identified 255 protease sequences from five catalytic classes using predicted proteins of the S. mansoni genome. The vast majority of these show significant similarity to proteins in KEGG and the Conserved Domain Database. Proteases include calpains, caspases, cytosolic and mitochondrial signal peptidases, proteases that interact with ubiquitin and ubiquitin-like molecules, and proteases that perform regulated intramembrane proteolysis. Comparative analysis of classes of important regulatory proteases find conserved active site domains, and where appropriate, signal peptides and transmembrane helices. Phylogenetic analysis provides support for inferring functional divergence among regulatory aspartic, cysteine, and serine proteases. Conclusion Numerous proteases are identified for the first time in S. mansoni. We characterized important regulatory proteases and focus analysis on these proteases to complement the growing knowledge base of digestive proteases. This work provides a foundation for expanding knowledge of proteases in Schistosoma species and examining their diverse function and potential as targets

  19. Increase of malaria attacks among children presenting concomitant infection by Schistosoma mansoni in Senegal

    OpenAIRE

    Diop Mamadou; Camara Pape; Akiana Jean; Mbaye Pape A; Le Hesran Jean-Yves; Sokhna Cheikh; Ly Abdoulaye; Druilhe Pierre

    2004-01-01

    Abstract Helminthic infections concomitant with malaria are common in inter-tropical areas. A recent study showed that mice co-infected with Schistosoma mansoni and Plasmodium chabaudi develop higher P. chabaudi parasitaemia and had a higher mortality rate. This important observation deserved to be further investigated among human populations. Malaria attacks were recorded in 512 children aged 6–15 years living in Richard Toll (Northern Senegal) among whom 336 were infected by S. mansoni, and...

  20. 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...

  1. Evaluation of portable microscopic devices for the diagnosis of Schistosoma and soil-transmitted helminth infection.

    Science.gov (United States)

    Bogoch, Isaac I; Coulibaly, Jean T; Andrews, Jason R; Speich, Benjamin; Keiser, Jennifer; Stothard, J Russell; N'goran, Eliézer K; Utzinger, Jürg

    2014-12-01

    The diagnosis of parasitic worm (helminth) infections requires specialized laboratory settings, but most affected individuals reside in locations without access to such facilities. We tested two portable microscopic devices for the diagnosis of helminth infections in a cross-sectional survey in rural Côte d'Ivoire. We examined 164 stool samples under a light microscope and then re-examined with a commercial portable light microscope and an experimental mobile phone microscope for the diagnosis of Schistosoma mansoni and soil-transmitted helminths. Additionally, 180 filtered urine samples were examined by standard microscopy and compared with the portable light microscope for detection of Schistosoma haematobium eggs. Conventional microscopy was considered the diagnostic reference standard. For S. mansoni, S. haematobium and Trichuris trichiura, the portable light microscope showed sensitivities of 84.8%, 78.6% and 81.5%, respectively, and specificities of 85.7%, 91.0% and 93.0%, respectively. For S. mansoni and T. trichiura, we found sensitivities for the mobile phone microscope of 68.2% and 30.8%, respectively, and specificities of 64.3% and 71.0%, respectively. We conclude that the portable light microscope has sufficient diagnostic yield for Schistosoma and T. trichiura infections, while the mobile phone microscope has only modest sensitivity in its current experimental set-up. Development of portable diagnostic technologies that can be used at point-of-sample collection will enhance diagnostic coverage in clinical and epidemiological settings. PMID:24776232

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

    International Nuclear Information System (INIS)

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

  3. [Pulmonary bilharziosis due to Schistosoma haematobium: pitfalls of species diagnosis. A case report from Libreville, Gabon].

    Science.gov (United States)

    N'Dong, F Ondo; Mbamendame, S; Assapi, M Ndong; Mbourou, J B; Roy, E; Kombila, M; Diané, C

    2005-01-01

    The purpose of this report is to describe a case of pulmonary schistosomiasis treated at la Fondation Jeanne Ebori in Libreville, Gabon. This case is exceptional due to the rarity of the disease and the schistosomiasis agent involved. The patient was a 47-year-old woman who presented with recurrent right-sided pneumonia 6 months after initial hospitalization and nonspecific antimicrobial therapy. Her general status was altered by hyperthermia, right chest pain, and repetitive bouts of hemoptysia. Because etiological diagnosis could not be achieved and clinical condition was deteriorating, the decision was taken to perform exploratory thoracotomy. Based on operative findings, medial and lower lobectomy was performed. Histological examination demonstrated granulomatous inflammatory lesions due to bilharziosis. Infection was attributed to Schistosoma haematobium that is the most common agent in pulmonary localizations. However Ziehl coloration raised the possibility of involvement of Schistosoma intercalatum that has never been observed in the lung and of a hybrid species. Natural hybridization between S. haematobium and S. intercalatum and the presence of active transmission of the Schistosoma hybrid has been suspected in Gabon. PMID:16038357

  4. Generalized Block Failure

    DEFF Research Database (Denmark)

    Jönsson, Jeppe

    2015-01-01

    shows that no readily available tests with a well-defined substantial eccentricity have been performed. This paper presents theoretical and experimental work leading towards generalized block failure capacity methods. Simple combination of normal force, shear force and moment stress distributions along......Block tearing is considered in several codes as a pure block tension or a pure block shear failure mechanism. However in many situations the load acts eccentrically and involves the transfer of a substantial moment in combination with the shear force and perhaps a normal force. A literature study...... yield lines around the block leads to simple interaction formulas similar to other interaction formulas in the codes....

  5. Blocked randomization with randomly selected block sizes.

    Science.gov (United States)

    Efird, Jimmy

    2011-01-01

    When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes. PMID:21318011

  6. Blocked Randomization with Randomly Selected Block Sizes

    Directory of Open Access Journals (Sweden)

    Jimmy Efird

    2010-12-01

    Full Text Available When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of individuals may be assigned to each arm of the study and thus decrease the power to detect statistically significant differences between groups. Block randomization is a commonly used technique in clinical trial design to reduce bias and achieve balance in the allocation of participants to treatment arms, especially when the sample size is small. This method increases the probability that each arm will contain an equal number of individuals by sequencing participant assignments by block. Yet still, the allocation process may be predictable, for example, when the investigator is not blind and the block size is fixed. This paper provides an overview of blocked randomization and illustrates how to avoid selection bias by using random block sizes.

  7. BLOCK H-MATRICES AND SPECTRUM OF BLOCK MATRICES

    Institute of Scientific and Technical Information of China (English)

    黄廷祝; 黎稳

    2002-01-01

    The block H-matrices are studied by the concept of G-functions, several concepts of block matrices are introduced. Equivalent characters of block H-matrices are obtained. Spectrum localizations claracterized by Gfunctions for block matrices are got.

  8. Endogenous lectins from cultured soybean cells: isolation of a protein immunologically cross-reactive with seed soybean agglutinin and analysis of its role in binding of Rhizobium japonicum

    OpenAIRE

    1986-01-01

    Incubation of Rhizobium japonicum with the cultured soybean cell line SB-1, originally derived from the roots of Glycine max, resulted in specific adhesion of the bacteria to the plant cells. This binding interaction appears to be mediated via carbohydrate recognition, since galactose can inhibit the heterotypic adhesion but glucose cannot. Affinity chromatography, on a Sepharose column derivatized with N- caproyl-galactosamine, of the supernatant fraction of a SB-1 cell suspension after enzy...

  9. Functional Bradyrhizobium japonicum NifA expression under a hybrid nptII-nifH promoter in E. coli and Acetobacter diazotrophicus SRT4.

    Science.gov (United States)

    Menéndez, C; Selman-Housein, G; Arrieta, J G; Coego, A; Hernández, L

    1998-01-01

    A hybrid promoter consisting of the in tandem fusion of the Tn5 nptII and the Klebsiella pneumoniae nifH promoters was constructed to study the functionality of the nif genes transcriptional activator NifA from Bradyrhizobium japonicum in two different host bacteria. beta-galactosidase experiments in E. coli revealed that the hybrid nptII-nifH promoter can behave as a constitutive or a NifA-inducible promoter depending on the aeration conditions. Expression of the B. japonicum NifA from the hybrid nptII-nifH promoter (plasmid pBPF204) induced "in trans" lacZ transcription from the Azotobacter chroococcum nifH promoter in E. coli and A. diazotrophicus cells grown at low pO2. Similarly, the plasmid pBPF204 increased nitrogenase activity in A. diazotrophicus cells grown under microaerobic conditions. Based on these results, we suggest that the B. japonicum NifA could function as an efficient O2-sensitive transcriptional activator of nif genes in genetically distant diazotrophic bacteria. PMID:10932742

  10. Lesson Thirteen Trifascicular Block

    Institute of Scientific and Technical Information of China (English)

    鲁端; 王劲

    2005-01-01

    @@ A complete trifascicular block would result in complete AV block. The idio ventricular rhythm has a slower rate and a wide QRS complex because the pacemaker is located at the peripheral part of the conduction system distal to the sites of the block1. Such a rhythm may be difficult to differentiate from bifascicular or bundle branch block combined with complete block at a higher level such as the AV node or His bundle2. Besides a slower ventricular rate, a change in the morphology of the QRS complex from a previous known bifascicular pattern would be strongly suggestive of a trifascicular origin of the complete AV block3. A His bundle recording is required for a definitive diagnosis, however.

  11. Block Advertisement Protocol

    OpenAIRE

    Nemirovsky, Danil

    2015-01-01

    Bitcoin, a decentralized cryptocurrency, has attracted a lot of attention from academia, financial service industry and enthusiasts. The trade-off between transaction confirmation throughput and centralization of hash power do not allow Bitcoin to perform at the same level as modern payment systems. Block Advertisement Protocol is proposed as a step to resolve this issue. The protocol allows block mining and block relaying to happen in parallel. The protocol dictates a miner to advertise the ...

  12. Dicty_cDB: SHD168 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001 1 CV682907 |CV682907.1 service...43_H06_sjs2-16-2B11-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001 1 CV682854 |CV682854.1 service

  13. Dicty_cDB: CHS126 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SJS Schistosoma japonicum cDNA, mRNA sequence. 56 8e-04 1 CV682907 |CV682907.1 service...43_H06_sjs2-16-2B11-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 8e-04 1 CV682854 |CV682854.1 service

  14. Block Scheduling Revisited.

    Science.gov (United States)

    Queen, J. Allen

    2000-01-01

    Successful block scheduling depends on provision of initial and ongoing instructional training. Teaching strategies should vary and include cooperative learning, the case method, the socratic seminar, synectics, concept attainment, the inquiry method, and simulations. Recommendations for maximizing block scheduling are outlined. (Contains 52…

  15. Cervical cytology as a diagnostic tool for female genital schistosomiasis: Correlation to cervical atypia and Schistosoma polymerase chain reaction

    Directory of Open Access Journals (Sweden)

    Pavitra Pillay

    2016-01-01

    Full Text Available Background: Female genital schistosomiasis (FGS is a tissue reaction to lodged ova of Schistosoma haematobium in the genital mucosa. Lesions can make the mucosa friable and prone to bleeding and discharge. Women with FGS may have an increased risk of HIV acquisition, and FGS may act as a cofactor in the development of cervical cancer. Objectives: To explore cytology as a method for diagnosing FGS and to discuss the diagnostic challenges in low-resource rural areas. The correlation between FGS and squamous cell atypia (SCA is also explored and discussed. Cytology results are compared to Schistosoma polymerase chain reaction (PCR in vaginal lavage and urine and in urine microscopy. Materials and Methods: In a clinical study, 394 women aged between 16 and 23 years from rural high schools in KwaZulu-Natal, South Africa, underwent structured interviews and the following laboratory tests: Cytology Papanicolaou (Pap smears for S. haematobium ova and cervical SCA, real-time PCR for Schistosoma-specific DNA in vaginal lavage and urine samples, and urine microscopy for the presence of S. haematobium ova. Results: In Pap smears, S. haematobium ova were detected in 8/394 (2.0%. SCA was found in 107/394 (27.1%, seven of these had high-grade squamous intraepithelial lesion (HSIL. Schistosoma specific DNA was detected in 38/394 (9.6% of vaginal lavages and in 91/394 (23.0% of urines. Ova were found microscopically in 78/394 (19.7% of urines. Conclusion: Schistosoma PCR on lavage was a better way to diagnose FGS compared to cytology. There was a significant association between S. haematobium ova in Pap smears and the other diagnostic methods. In low-resource Schistosoma-endemic areas, it is important that cytology screeners are aware of diagnostic challenges in the identification of schistosomiasis in addition to the cytological diagnosis of SCA. Importantly, in this study, three of eight urines were negative but showed Schistosoma ova in their Pap smear, and

  16. The impact of repeated treatment with praziquantel of schistosomiasis in children under six years of age living in an endemic area for Schistosoma haematobium infection

    Directory of Open Access Journals (Sweden)

    Mduluza T

    2001-01-01

    Full Text Available Praziquantel was given every eight weeks for two years to children aged under six years of age, living in a Schistosoma haematobium endemic area. Infection with S. haematobium and haematuria were examined in urine and antibody profiles (IgA, IgE, IgM, IgG1, IgG2, IgG3, and IgG4 against S. haematobium adult worm and egg antigens were determined from sera collected before each treatment. Chemotherapy reduced infection prevalence and mean intensity from 51.8% and 110 eggs per 10 ml urine, respectively, before starting re-treatment programme to very low levels thereafter. Praziquantel is not accumulated after periodic administration in children. Immunoglobulin levels change during the course of treatment with a shift towards 'protective' mechanisms. The significant changes noted in some individuals were the drop in 'blocking' IgG2 and IgG4 whereas the 'protecting' IgA and IgG1 levels increased. The antibody profiles in the rest of the children remained generally unchanged throughout the study and no haematuria was observed after the second treatment. The removal of worms before production of large number of eggs, prevented the children from developing morbidity.

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

    OpenAIRE

    Monde, Concillia; Syampungani, Stephen; Brink, van den, L.

    2016-01-01

    The effect of the pesticide endosulfan on predator–prey interactions between catfish and Schistosoma host snails was assessed in static tank experiments. Hybrid catfish (Clarias gariepinus × C. ngamensis) and Bulinus globosus were subjected to various endosulfan concentrations including an untreated control. The 48- and 96-h LC50 values for catfish were 1.0 and 50 values for snails were 1137 and 810 µg/L. To assess sublethal effects on the feeding of the catfish on B. globosus, endosulfan con...

  18. Sequential histological changes in Biomphalaria glabrata during the course of Schistosoma mansoni infection

    Directory of Open Access Journals (Sweden)

    Queli Teixeira Lemos

    2001-07-01

    Full Text Available Biomphalaria glabrata, highly susceptible to Schistosoma mansoni, were seen to shed less and less cercariae along the time of infection. Histological examination kept a close correlation with this changing pattern of cercarial shedding, turning an initial picture of no-reaction (tolerance gradually into one of hemocyte proliferation with formation of focal encapsulating lesions around disintegrating sporocysts and cercariae, a change that became disseminated toward the 142nd day post miracidial exposure. Findings were suggestive of a gradual installation of acquired immunity in snails infected with S. mansoni.

  19. Developmental regulation of protein kinase A expression and activity in Schistosoma mansoni

    OpenAIRE

    Swierczewski, Brett E.; Davies, Stephen J.

    2010-01-01

    c-AMP-dependent protein kinases (PKAs) are the main transducers of cAMP signaling in eukaryotic cells. Recently we reported the identification and characterization of a PKA catalytic subunit (SmPKA-C) in Schistosoma mansoni that is required for adult schistosome viability in vitro. To gain further insights into the role of SmPKA-C in biological processes during the schistosome life cycle, we undertook a quantitative analysis of SmPKA-C mRNA expression in different life cycle stages. Our data ...

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Labelling of Schistosoma mansoni cercariae with 99 m technetium: a preliminary communication

    International Nuclear Information System (INIS)

    The labelling of Schistosoma mansoni cercariae with technetium 99 m (99 m Tc) is performed. The effect of stannous chloride concentration in the labelling process, the stability of the labelling and the viability of the 99 m Tc labeled cercariae are studied. The incorporation of the radioactivity in the cercariae increases with an increase in the stannous chloride concentration reaching constant values threshold 13000 u M. The characteristic motion of the cercariae was only modify at the concentration of 130000 u M. (M.A.C.)

  2. Lichtphysiologische Untersuchungen an Cercarien von Schistosoma mansoni, eines Erregers menschlicher intestinaler Bilharziose

    OpenAIRE

    Kopf, Stefan

    2007-01-01

    In unserer Arbeit führten wir lichtreizphysiologische Untersuchungen an Cercarien von Schistosoma mansoni durch, der Erreger der intestinalen Bilharziose. Wir konnten nachweisen, daß Cercarien ihre höchste Aktivität bei 500 nm Lichtwellenlänge und 10000 Cd Lichtstärke haben. Ferner stellten wir fest, daß Dunkelreize die Passivphasen und die anschließende Aktivphase verkürzen, während Lichtreize die Passivphasen und die folgende Aktivphase verlängern. Eine Dunkelreizgabe in der Aktivphase verk...

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

    Czech Academy of Sciences Publication Activity Database

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

    2014-01-01

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

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

    OpenAIRE

    Ana Lisa do Vale Gomes; Fábio L Melo; Roberto P Werkhauser; Frederico GC Abath

    2006-01-01

    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). Th...

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

    Czech Academy of Sciences Publication Activity Database

    Fajtová, Pavla; Štefanic, S.; Hradilek, Martin; Dvořák, Jan; Vondrášek, Jiří; Jílková, Adéla; Ulrychová, Lenka; McKerrow, J. H.; Caffrey, C. R.; Mareš, Michael; Horn, Martin

    2015-01-01

    Roč. 9, č. 6 (2015), e0003827/1-e0003827/24. ISSN 1935-2735 R&D Projects: GA ČR(CZ) GAP302/11/1481; GA MŠk LO1302 Institutional support: RVO:61388963 ; RVO:68378050 Keywords : Schistosoma mansoni * schistosomiasis * prolyl oligopeptidase * blood fluke Subject RIV: CE - Biochemistry; EB - Genetics ; Molecular Biology (UMG-J) Impact factor: 4.446, year: 2014 http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0003827

  6. Predictability of blocking

    International Nuclear Information System (INIS)

    Tibaldi and Molteni (1990, hereafter referred to as TM) had previously investigated operational blocking predictability by the ECMWF model and the possible relationships between model systematic error and blocking in the winter season of the Northern Hemisphere, using seven years of ECMWF operational archives of analyses and day 1 to 10 forecasts. They showed that fewer blocking episodes than in the real atmosphere were generally simulated by the model, and that this deficiency increased with increasing forecast time. As a consequence of this, a major contribution to the systematic error in the winter season was shown to derive from the inability of the model to properly forecast blocking. In this study, the analysis performed in TM for the first seven winter seasons of the ECMWF operational model is extended to the subsequent five winters, during which model development, reflecting both resolution increases and parametrisation modifications, continued unabated. In addition the objective blocking index developed by TM has been applied to the observed data to study the natural low frequency variability of blocking. The ability to simulate blocking of some climate models has also been tested

  7. Block Cipher Analysis

    DEFF Research Database (Denmark)

    Miolane, Charlotte Vikkelsø

    ensurethat no attack violatesthe securitybounds specifiedbygeneric attack namely exhaustivekey search and table lookup attacks. This thesis contains a general introduction to cryptography with focus on block ciphers and important block cipher designs, in particular the Advanced Encryption Standard......(AES).Wedescribe the mostgeneraltypes ofblock cipher cryptanalysis but concentrate on the algebraic attacks. While the algebraic techniques have been successful oncertainstreamcipherstheirapplicationtoblock ciphershasnot shown any significant results so far. This thesis contributes to the field of algebraic attacks on...... algebraic results on small scale variants of AES. In the final part of the thesis we present a new block cipher proposal Present and examine its security against algebraic and differential cryptanalysis in particular....

  8. Effects of NaCl Stress on Chlorophyll Fluorescence Parameters in Cinnamomum japonicum var. chenii%NaCl胁迫对普陀樟叶绿素荧光参数的影响

    Institute of Scientific and Technical Information of China (English)

    李影丽; 汪奎宏; 杜国坚; 许利群; 杨华; 肖纪军

    2008-01-01

    [Objective] Study on the changes of chlorophyll fluorescence parameters in Cinnamomum japonicum var. chenii under NaCl stress. [Method] The seedling growth increment, chlorophyll content and chlorophyll fluorescence parameters in leaves of 1-year old Cinnamomum japonicum var. chenii were investigated in field experiment. [Result] Under NaCl stress, seedling growth increment reduced and the chlorophyll content decreased to a stable value; changes of Fv/Fm and Fv/Fo showed identical increasing trend and double peak type. With the aggravation of salt stress, most variations were ob- served in Fo, correlations among chlorophyll fluorescence parameters presented "rise-drop" trend (in the treatment of 7 g/L NaCl). [Condusion] Cinna-momum japonicum var. chenii is endowed with strong salt resistance and wide adaptability.

  9. Block copolymer battery separator

    Energy Technology Data Exchange (ETDEWEB)

    Wong, David; Balsara, Nitash Pervez

    2016-04-26

    The invention herein described is the use of a block copolymer/homopolymer blend for creating nanoporous materials for transport applications. Specifically, this is demonstrated by using the block copolymer poly(styrene-block-ethylene-block-styrene) (SES) and blending it with homopolymer polystyrene (PS). After blending the polymers, a film is cast, and the film is submerged in tetrahydrofuran, which removes the PS. This creates a nanoporous polymer film, whereby the holes are lined with PS. Control of morphology of the system is achieved by manipulating the amount of PS added and the relative size of the PS added. The porous nature of these films was demonstrated by measuring the ionic conductivity in a traditional battery electrolyte, 1M LiPF.sub.6 in EC/DEC (1:1 v/v) using AC impedance spectroscopy and comparing these results to commercially available battery separators.

  10. Blocking in Category Learning

    OpenAIRE

    Bott, Lewis; Hoffman, Aaron B.; Murphy, Gregory L.

    2007-01-01

    Many theories of category learning assume that learning is driven by a need to minimize classification error. When there is no classification error, therefore, learning of individual features should be negligible. We tested this hypothesis by conducting three category learning experiments adapted from an associative learning blocking paradigm. Contrary to an error-driven account of learning, participants learned a wide range of information when they learned about categories, and blocking effe...

  11. Concord Housing Blocks

    OpenAIRE

    Kumaraswamy, Mohan

    2002-01-01

    One element of the CIVCAL project Web-based resources containing images, tables, texts and associated data on the construction of Concord type Housing Blocks. A high rise public housing project using prefabriction and advanced formwork systems. Both Harmony and Concord Blocks are designed on the basis of standard modular flats which permit the use of factory produced components and a construction sequence which makes extensive use of advanced formwork systems.

  12. Efficient Block Truncation Coding

    Directory of Open Access Journals (Sweden)

    K.Somasundaram,

    2010-09-01

    Full Text Available Block Truncation Coding (BTC is one of the lossy image compression techniques. The computational complexity involved in this method is very simple. In the proposed method, the feature of inter-pixel correlation is exploited to further reduce the requirement of bits to store a block. The proposed method gives very good performance in terms of bit-rate and PSNR values when compared to the conventional BTC.

  13. 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 infec...

  14. Structural basis for inhibition of the cathepsin B drug target from the human blood fluke, Schistosoma mansoni

    Czech Academy of Sciences Publication Activity Database

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

    Hydra : -, 2012. s. 60-60. [Molecular and Cellular Biology of Helminth Parasites. International Conference /7./. 02.09.2012-07.09.2012, Hydra] R&D Projects: GA MŠk LH12023; GA ČR GA203/09/1585 Institutional support: RVO:61388963 Keywords : cathepsin B1 * Schistosoma * protease * structures Subject RIV: CE - Biochemistry

  15. Dynamics of Schistosoma haematobium egg output and associated infection parameters following treatment with praziquantel in school-aged children

    OpenAIRE

    Stete Katarina; Krauth Stefanie J; Coulibaly Jean T; Knopp Stefanie; Hattendorf Jan; Müller Ivan; Lohourignon Laurent K; Kern Winfried V; N’Goran Eliézer K; Utzinger Jürg

    2012-01-01

    Abstract Background Praziquantel is the drug of choice in preventive chemotherapy targeting schistosomiasis. Increasing large-scale administration of praziquantel requires monitoring of drug efficacy to detect early signs of development of resistance. Standard protocols for drug efficacy monitoring are necessary. Here, we determined the optimal time point for praziquantel efficacy assessment against Schistosoma haematobium and studied the dynamics of infection parameters following treatment. ...

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

    Czech Academy of Sciences Publication Activity Database

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

    2010-01-01

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

  17. Evaluation of the In Vivo Activity of Tribendimidine against Schistosoma mansoni, Fasciola hepatica, Clonorchis sinensis, and Opisthorchis viverrini▿

    OpenAIRE

    Keiser, Jennifer; Shu-Hua, Xiao; Chollet, Jacques; Tanner, Marcel; Utzinger, Jürg

    2006-01-01

    We examined the in vivo activity of tribendimidine against selected trematodes. A single 150-mg/kg dose of tribendimidine achieved a 99.1% reduction of Clonorchis sinensis in rats. A 400-mg/kg dose of tribendimidine reduced Opisthorchis viverrini in hamsters by 95.7%. High doses of tribendimidine showed no activity against Schistosoma mansoni and Fasciola hepatica.

  18. 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

  19. Optimización de inoculantes para la agricultura sustentable en soja: rol de los flagelos de Bradyrhizobium japonicum en la competición para la nodulación

    OpenAIRE

    Althabegoiti, María

    2010-01-01

    Objetivos de este trabajo de tesis Objetivo general: Generar nuevo conocimiento acerca de la movilidad de B. japonicum. A partir de ello procurar una mejora en la competición para la nodulación de las cepas de B. japonicum empleadas como inoculantes. Objetivos específicos: - Analizar el comportamiento de una cepa de mayor movilidad en la competición para la nodulación, seleccionada de forma natural (sin manipulación genética) y mediante una técnica reproducible. - Analizar la ...

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

    Directory of Open Access Journals (Sweden)

    Ironside Joe E

    2011-07-01

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

  1. Reduced protective effect of Plasmodium berghei immunization by concurrent Schistosoma mansoni infection

    Directory of Open Access Journals (Sweden)

    Ramon F Laranjeiras

    2008-11-01

    Full Text Available Studies on concomitant schistosomiasis and human and experimental malaria have shown a variation in the immunospecific response, as well as an increase in the severity of both parasitoses. In the present study, a murine co-infection model was used to determine the effects of a co-infection with Schistosoma mansoni and Plasmodium berghei on the protective immunity acquired by repeated malarial infections and subsequent curative treatment with chloroquine. Our results have demonstrated that, compared to an infection with P. berghei only, the co-infection increases the malarial parasitaemia and decreases the survival rate. Indeed, mice that were immunized by infection and treatment with drug displayed no mortality whereas co-infected mice showed a reduced protective efficacy of immunization against P. berghei (mortality > 60%. Interestingly, this high mortality rate was not associated with high levels of parasitaemia. Our findings support the idea of a suppressive effect of a Schistosoma co-infection on the anti-malarial protection by immunization. This result reveals a possible drawback of the development of anti-malarial vaccines, especially considering the wide endemic areas for both parasitoses.

  2. Rate of action of schistosomicides in mice infected with Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Naftale Katz

    1989-12-01

    Full Text Available Mice infected with adult Schistosoma mansoni were dosed with a single oral dose of 125 or 250 mg/kg oltipraz, 50 or 100 mg/kg oxamniquine, or 200 or 400 mg/kg praziquantel. The mortality rate of worms and oogram changes were determined between 1 and 16 weeks after dosing. The time required between dosing and postmortem to obtain maximum effectiveness was 1 week for praziquantel, 2 weeks for oxamniquine and 8 weeks for oltipraz. Changes in oograms persisted throughout most of the experiment, although relapse has been observed at the 4th week on.Camundongos infectados experimentalmente com Schistosoma mansoni foram tratados por via oral com dose única de 125 ou 250 mg/kg de oltipraz, 50 ou 100 mg/kg de oxamniquine, e 200 ou 400 mg/kg de praziquantel. O número de vermes e alteração do oograma foram determinados entre a 1ª e 16ª semanas após o tratamento. O tempo necessário para observar o máximo de atividade da droga foi de 1 semana para o praziquantel, 2 semanas para o oxamniquine e 8 semanas para o oltipraz. Alterações do oograma persistiram durante o período de observação, embora recidiva tenha sido detectada, já na 4ª semana, com as drogas utilizadas.

  3. Cloning of three ZIP/Nramp transporter genes from a Ni hyperaccumulator plant thlaspi japonicum and their Ni2+ transport abilities

    OpenAIRE

    Mizuno, Takahumi; Usui, Koji; Horie, Kenji; Nosaka, Shiro; Mizuno, Naoharu; Obata, Hitoshi

    2005-01-01

    Ni homeostasis is essential for plant cell activity, but the mechanisms of Ni-transport and delivery are unknown. To elucidate the role of ZIP and NRAMP metal-transporters for Ni2+-transport and homeostasis, we cloned their homologous genes from the Ni hyperaccumulator Thlaspi japonicum, and investigated their Ni-transporting abilities by expression in yeast. The deduced amino acid sequences of the two Zip transporter genes (TjZnt1, TjZnt2) and one Nramp transporter gene cloned had high homol...

  4. Impression block with orientator

    International Nuclear Information System (INIS)

    Tool review, namely the impression block, applied to check the shape and size of the top of fish as well as to determine the appropriate tool for fishing operation was realized. For multiple application and obtaining of the impress depth of 3 cm and more, the standard volumetric impression blocks with fix rods are used. However, the registered impress of fish is not oriented in space and the rods during fishing are in the extended position. This leads to rods deformation and sinking due to accidental impacts of impression block over the borehole irregularity and finally results in faulty detection of the top end of fishing object in hole. The impression blocks with copy rods and fixed magnetic needle allow estimating the object configuration and fix the position of magnetic needle determining the position of the top end of object in hole. However, the magnetic needle fixation is realized in staged and the rods are in extended position during fishing operations as well as it is in standard design. The most efficient tool is the impression block with copy rods which directs the examined object in the borehole during readings of magnetic needles data from azimuth plate and averaging of readings. This significantly increases the accuracy of fishing toll direction. The rods during fishing are located in the body and extended only when they reach the top of fishing object

  5. Uniaxial backfill block compaction

    International Nuclear Information System (INIS)

    The main parts of the project were: to make a literature survey of the previous uniaxial compaction experiments; do uniaxial compaction tests in laboratory scale; and do industrial scale production tests. Object of the project was to sort out the different factors affecting the quality assurance chain of the backfill block uniaxial production and solve a material sticking to mould problem which appeared during manufacturing the blocks of bentonite and cruched rock mixture. The effect of mineralogical and chemical composition on the long term functionality of the backfill was excluded from the project. However, the used smectite-rich clays have been tested for mineralogical consistency. These tests were done in B and Tech OY according their SOPs. The objective of the Laboratory scale tests was to find right material- and compaction parameters for the industrial scale tests. Direct comparison between the laboratory scale tests and industrial scale tests is not possible because the mould geometry and compaction speed has a big influence for the compaction process. For this reason the selected material parameters were also affected by the previous compaction experiments. The industrial scale tests were done in summer of 2010 in southern Sweden. Blocks were done with uniaxial compaction. A 40 tons of the mixture of bentonite and crushed rock blocks and almost 50 tons of Friedland-clay blocks were compacted. (orig.)

  6. Block diagonal and schur complement preconditioners for block-toeplitz systems with small size blocks

    OpenAIRE

    Ching, WK; Ng, MK; Wen, YW

    2007-01-01

    In this paper we consider the solution of Hermitian positive definite block-Toeplitz systems with small size blocks. We propose and study block diagonal and Schur complement preconditioners for such block-Toeplitz matrices. We show that for some block-Toeplitz matrices, the spectra of the preconditioned matrices are uniformly bounded except for a fixed number of outliers where this fixed number depends only on the size of the block. Hence, conjugate gradient type methods, when applied to solv...

  7. Nymble Blocking System

    Directory of Open Access Journals (Sweden)

    Anand Joshi

    2012-05-01

    Full Text Available In order to allow users to access Internet services privately, anonymizing networks like Tor uses a series of routers to hide the client’s IP address from the server. These networks, however, have been marred by users employing this anonymity for abusive purposes such as defacing popular web sites. Usually, web site administrators rely on IP-address blocking in order to disable access to misbehaving users, but it is impractical if the abuser routes through an anonymizing network. In order to avoid this, administrators bar all known exit nodes of the anonymizing network, thereby denying anonymous access to all the users(whether misbehaving or not. To solve this issue, we introduce Nymble, a system where servers blacklist misbehaving users, thereby blocking users without affecting their anonymity. Nymble is thus agnostic to varied definitions of misbehavior. Servers can block users for any reason, and the privacy of blacklisted users is not affected in any case.

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

    Directory of Open Access Journals (Sweden)

    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

  9. Bactericidal block copolymer micelles.

    Science.gov (United States)

    Vyhnalkova, Renata; Eisenberg, Adi; van de Ven, Theo

    2011-05-12

    Block copolymer micelles with bactericidal properties were designed to deactivate pathogens such as E. coli bacteria. The micelles of PS-b-PAA and PS-b-P4VP block copolymers were loaded with biocides TCMTB or TCN up to 20 or 30 wt.-%, depending on the type of antibacterial agent. Bacteria were exposed to loaded micelles and bacterial deactivation was evaluated. The micelles loaded with TCN are bactericidal; bacteria are killed in less than two minutes of exposure. The most likely interpretation of the data is that the biocide is transferred to the bacteria by repeated micelle/bacteria contacts, and not via the solution. PMID:21275041

  10. E-Block: A Tangible Programming Tool with Graphical Blocks

    OpenAIRE

    Danli Wang; Yang Zhang; Shengyong Chen

    2013-01-01

    This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks. With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer. The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transfer...

  11. Effects of Block Scheduling

    Directory of Open Access Journals (Sweden)

    William R. Veal

    1999-09-01

    Full Text Available This study examined the effects of a tri-schedule on the academic achievement of students in a high school. The tri-schedule consists of traditional, 4x4 block, and hybrid schedules running at the same time in the same high school. Effectiveness of the schedules was determined from the state mandated test of basic skills in reading, language, and mathematics. Students who were in a particular schedule their freshman year were tested at the beginning of their sophomore year. A statistical ANCOVA test was performed using the schedule types as independent variables and cognitive skill index and GPA as covariates. For reading and language, there was no statistically significant difference in test results. There was a statistical difference mathematics-computation. Block mathematics is an ideal format for obtaining more credits in mathematics, but the block format does little for mathematics achievement and conceptual understanding. The results have content specific implications for schools, administrations, and school boards who are considering block scheduling adoption.

  12. Spice Blocks Melanoma Growth

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Curcumin, the pungent yellow spice found in both turmeric and curry powders, blocks a key biological pathway needed for development of melanoma and other cancers, according to a study that appears in the journal Cancer. Researchers from The University of Texas M. D. Anderson Cancer Center demonstrate how curcumin stops laboratory strains of…

  13. Contaminated soil concrete blocks

    NARCIS (Netherlands)

    Korte, de A.C.J.; Brouwers, H.J.H.; Limbachiya, Mukesh C.; Kew, Hsein Y.

    2009-01-01

    According to Dutch law the contaminated soil needs to be remediated or immobilised. The main focus in this article is the design of concrete blocks, containing contaminated soil, that are suitable for large production, financial feasible and meets all technical and environmental requirements. In ord

  14. Effects of the Bradyrhizobium japonicum waaL (rfaL Gene on Hydrophobicity, Motility, Stress Tolerance, and Symbiotic Relationship with Soybeans

    Directory of Open Access Journals (Sweden)

    Jun-Gu Noh

    2015-07-01

    Full Text Available We cloned and sequenced the waaL (rfaL gene from Bradyrhizobium japonicum, which infects soybean and forms nitrogen-fixing nodules on soybean roots. waaL has been extensively studied in the lipopolysaccharide (LPS biosynthesis of enteric bacteria, but little is known about its function in (bradyrhizobial LPS architecture. To characterize its role as O-antigen ligase in the LPS biosynthesis pathway, we constructed a waaL knock-out mutant and its complemented strain named JS015 and CS015, respectively. LPS analysis showed that an LPS structure of JS015 is deficient in O-antigen as compared to that of the wild type and complemented strain CS015, suggesting that WaaL ligates the O-antigen to lipid A-core oligosaccharide to form a complete LPS. JS015 also revealed increased cell surface hydrophobicity, but it showed decreased motility in soft agar plates. In addition to the alteration in cell surface properties, disruption of the waaL gene caused increased sensitivity of JS015 to hydrogen peroxide, osmotic pressure, and novobiocin. Specifically, plant tests revealed that JS015 failed to nodulate the host plant soybean, indicating that the rhizobial waaL gene is responsible for the establishment of a symbiotic relationship between soybean and B. japonicum.

  15. Synthesis of silver nanoparticles on the basis of low and high molar mass exopolysaccharides of Bradyrhizobium japonicum 36 and its antimicrobial activity against some pathogens.

    Science.gov (United States)

    Rasulov, Bakhtiyor; Rustamova, Nigora; Yili, Abulimiti; Zhao, Hai-Qing; Aisa, Haji A

    2016-07-01

    Silver nanoparticles (SNPs) were synthesized on the basis of exopolysaccharides (low and high molar mass) of diazotrophic Bradyrhizobium japonicum 36 strain. The synthesis of SNPs was carried out by direct reduction of silver nitrate with ethanol-insoluble (high molar mass, HMW) and ethanol-soluble (low molar mass, LMW) fractions of exopolysaccharides (EPS), produced by diazotrophic strain B. japonicum 36. SNPs were characterized using UV-vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). SNPs synthesized on the basis of LMW EPS absorbed radiation in the visible regions of 420 nm, whereas SNPs based on the HMW EPS have a wavelength maximum at 450 nm because of the strong SPR transition. Moreover, the antibacterial and antifungal activities of the SNPs were examined in vitro against Escherichia coli, Staphylococcus aureus, and Candida albicans. SNPs synthesized on the basis of LMW EPS were active than those synthesized on the basis of HMW EPS. Besides, UV-visible spectroscopic evaluation confirmed that SNPs synthesized on the basis of LMW EPS were far more stable than those obtained on the basis of HMW EPS. PMID:26603749

  16. Effect of metal stress on photosynthetic pigments in the Cu-hyperaccumulating lichens Cladonia humilis and Stereocaulon japonicum growing in Cu-polluted sites in Japan.

    Science.gov (United States)

    Nakajima, Hiromitsu; Yamamoto, Yoshikazu; Yoshitani, Azusa; Itoh, Kiminori

    2013-11-01

    To understand the ecology and physiology of metal-accumulating lichens growing in Cu-polluted sites, we investigated lichens near temple and shrine buildings with Cu roofs in Japan and found that Stereocaulon japonicum Th. Fr. and Cladonia humilis (With.) J. R. Laundon grow in Cu-polluted sites. Metal concentrations in the lichen samples collected at some of these sites were determined by inductively coupled plasma mass spectroscopy (ICP-MS). UV-vis absorption spectra of pigments extracted from the lichen samples were measured, and the pigment concentrations were estimated from the spectral data using equations from the literature. Secondary metabolites extracted from the lichen samples were analyzed by high-performance liquid chromatography (HPLC) with a photodiode array detector. We found that S. japonicum and C. humilis are Cu-hyperaccumulating lichens. Differences in pigment concentrations and their absorption spectra were observed between the Cu-polluted and control samples of the 2 lichens. However, no correlation was found between Cu and pigment concentrations. We observed a positive correlation between Al and Fe concentrations and unexpectedly found high negative correlations between Al and pigment concentrations. This suggests that Al stress reduces pigment concentrations. The concentrations of secondary metabolites in C. humilis growing in the Cu-polluted sites agreed with those in C. humilis growing in the control sites. This indicates that the metabolite concentrations are independent of Cu stress. PMID:23953993

  17. Edit Distance with Block Deletions

    OpenAIRE

    Dana Shapira; Storer, James A.

    2011-01-01

    Several variants of the edit distance problem with block deletions are considered. Polynomial time optimal algorithms are presented for the edit distance with block deletions allowing character insertions and character moves, but without block moves. We show that the edit distance with block moves and block deletions is NP-complete (Nondeterministic Polynomial time problems in which any given solution to such problem can be verified in polynomial time, and any NP problem can be converted into...

  18. Fermion-Scalar Conformal Blocks

    CERN Document Server

    Iliesiu, Luca; Poland, David; Pufu, Silviu S; Simmons-Duffin, David; Yacoby, Ran

    2015-01-01

    We compute the conformal blocks associated with scalar-scalar-fermion-fermion 4-point functions in 3D CFTs. Together with the known scalar conformal blocks, our result completes the task of determining the so-called `seed blocks' in three dimensions. Conformal blocks associated with 4-point functions of operators with arbitrary spins can now be determined from these seed blocks by using known differential operators.

  19. Protection of sheep against Schistosoma bovis using cryopreserved radiation-attenuated schistosomula

    International Nuclear Information System (INIS)

    Three sheep were vaccinated with two doses of 3 krad-irradiated cryopreserved Schistosoma bovis schistosomula containing 20,000 and 17,000 organisms respectively, injected intramuscularly 23 days apart after storage in liquid nitrogen for between 9 and 46 days. A challenge of 5360 S. bovis cercariae was administered percutaneously approximately four weeks after the last vaccine dose to these animals and to three controls. Post-challenge the vaccinated animals gained significantly more weight (27% v. 9%), produced fewer eggs in their faeces, showed a smaller reduction in PCV values (-18% v. -27%) and were over-all in better condition than control animals. At perfusion 49.1% fewer adult worms were found in the vaccinated sheep than in controls. The tissue egg burdens were similar in both groups. Histopathologically both groups were similar except that fewer and smaller egg lesions were observed in the livers of vaccinated animals. (author)

  20. Schistosoma mansoni: migration potential of normal and radiation attenuated parasites in naive guinea pigs

    International Nuclear Information System (INIS)

    Compressed tissue autoradiography using [75Se]selenomethionine labelled parasites has been used to investigate the migration potential of normal and radiation attenuated cercariae of Schistosoma mansoni in naive guinea pigs. By Day 14 after infection. 44% of normal parasites were detected as reduced silver foci in the liver; this value corresponded well with the number of liver parasites recovered by retrograde perfusion of the hepatic portal system on Day 42 (42% of the challenge). In contrast, cercariae subjected to 50 krad of gamma irradiation failed to migrate out of the skin. The migration capacity of 20 krad irradiated parasites was less severely affected in that about half of the challenge parasites reached the lungs, but virtually none moved to the liver. These data are discussed in relation to the kinetics of immunity induced in guinea pigs by infection or vaccination with normal or radiation attenuated parasites

  1. Schistosoma mansoni: migration potential of normal and radiation attenuated parasites in naive guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, H.; McLaren, D.J.

    1987-02-01

    Compressed tissue autoradiography using (75Se)selenomethionine labelled parasites has been used to investigate the migration potential of normal and radiation attenuated cercariae of Schistosoma mansoni in naive guinea pigs. By Day 14 after infection. 44% of normal parasites were detected as reduced silver foci in the liver; this value corresponded well with the number of liver parasites recovered by retrograde perfusion of the hepatic portal system on Day 42 (42% of the challenge). In contrast, cercariae subjected to 50 krad of gamma irradiation failed to migrate out of the skin. The migration capacity of 20 krad irradiated parasites was less severely affected in that about half of the challenge parasites reached the lungs, but virtually none moved to the liver. These data are discussed in relation to the kinetics of immunity induced in guinea pigs by infection or vaccination with normal or radiation attenuated parasites.

  2. Schistosoma bovis, S. intercalatum and S. haematobium: methods for in vivo radiolabelling of cercariae with radioselenium

    International Nuclear Information System (INIS)

    Cercariae of Schistosoma bovis, S. intercalatum and S. haematobium were radiolabelled by individual exposure of their respective host snails to 75Se-methionine in 1 ml water for a period of 20 hours. Maximum cercaria-bound radioactivity was obtained four to seven days after labelling of snails, but detectable levels of radioactivity incorporation were obtained with all three species for a period of 32 days. The radiolabelling procedure did not interfere with the production of cercariae or with the biological characteristics of the labelled larvae. The described research opens the way for the application of various radioisotope tracer systems in studies on host-parasite relationships between cercariae and schistosomula of terminal-spined species of schistosomes and the final host. (author)

  3. Protection of sheep against Schistosoma bovis using cryopreserved radiation-attenuated schistosomula

    Energy Technology Data Exchange (ETDEWEB)

    James, E.R.; Dobinson, A.R.; Andrews, B.J.; Bickle, Q.D.; Taylor, M.G.; Ham, P.J. (London School of Hygiene and Tropical Medicine, St. Albans (UK). Winches Farm Field Station); Lucas, S.B. (University Coll. Hospital, London (UK))

    1985-03-01

    Three sheep were vaccinated with two doses of 3 krad-irradiated cryopreserved Schistosoma bovis schistosomula containing 20,000 and 17,000 organisms respectively, injected intramuscularly 23 days apart after storage in liquid nitrogen for between 9 and 46 days. A challenge of 5360 S. bovis cercariae was administered percutaneously approximately four weeks after the last vaccine dose to these animals and to three controls. Post-challenge the vaccinated animals gained significantly more weight (27% v. 9%), produced fewer eggs in their faeces, showed a smaller reduction in PCV values (-18% v. -27%) and were over-all in better condition than control animals. At perfusion 49.1% fewer adult worms were found in the vaccinated sheep than in controls. The tissue egg burdens were similar in both groups. Histopathologically both groups were similar except that fewer and smaller egg lesions were observed in the livers of vaccinated animals.

  4. Attrition of schistosomes in an irradiation-attenuated cercarial immunization model of Schistosoma mansoni

    International Nuclear Information System (INIS)

    The attrition of Schistosoma mansoni challenge worms was studied in irradiation-attenuated cercaria-immunized mice as a function of site and time. The peak recovery of schistosomula from the lungs of immunized mice was delayed 2 days in comparison with non-immunized controls. The difference between the peak recoveries of control and immunized mice accounted for about half of the final attrition observed at the 7-week adult worm stge. Hepatic-mesenteric vein worm recoveries obtained 10 to 42 days after challenge were reduced in most cases at least as much as the 49-day counts. Somewhat higher reductions were observed at 14 to 28 days than at 49 days, confirming the evidence of delayed migration obtained at the lung phase. These findings, coupled with histologic observations, indicate that at least half of the worm elimination attributable to immunization occurs 8 or more days after the challenge infection

  5. 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

  6. Detection of circulating polysaccharide antigen of Schistosoma mansoni in hamster sera by crossed immunoelectrophoresis

    Directory of Open Access Journals (Sweden)

    Margareth Fernandes

    1988-04-01

    Full Text Available Crossed immunoelectrophoresis (IEC was used for detection of free and complexed circulating polisaccharide anodic antigen (AgCA of Schistosoma mansoni in sera of infected hamsters. An attempt was also done to detect AgCA in human sera from patients infected with S. mansoni. The conditions for isolation and detection of complexed AgCA were established. The sensitivity of IEC was increased by incorporation of 2% polyethylene glicol (PEG to the agarose and by maintaining the system at 4°C during the electrophoretic run. Free AgCA was detected in 12 and the complexed in 30 of the 37 hamsters sera analysed. Correlation between AgCA (free and complexed and the parasite load was observed. AgCA was not detected, under the experimental conditions used, in human sera from 7 patients in the acute and 23 in the chronic phase of infection.

  7. Schistosomicidal evaluation of Zanthoxylum naranjillo and its isolated compounds against Schistosoma mansoni adult worms.

    Science.gov (United States)

    Braguine, Caio G; Costa, Eveline S; Magalhães, Lizandra G; Rodrigues, Vanderlei; da Silva Filho, Ademar A; Bastos, Jairo K; Silva, Márcio L A; Cunha, Wilson R; Januário, Ana H; Pauletti, Patrícia M

    2009-01-01

    Chemical investigation of the EtOAc fraction (EF) obtained from the ethanolic extract of Zanthoxylum naranjillo (Rutaceae) leaves (EE) by preparative HPLC resulted in the isolation of protocatechuic acid (1), gallic acid (2), p-hydroxybenzoic acid (3), and 5-O-caffeoylshikimic acid (4). This is the first time that the presence of compounds 1-4 in Z. naranjillo has been reported. Compounds 1-4, the EE, and EF were tested in vitro against Schistosoma mansoni adult worms. The results showed that the S. mansoni daily egg production decreased by 29.8%, 13.5%, 28.4%, 17.7%, 16.3%, and 6.4%, respectively. Compounds 1 and 3 were also able to separate adult worm pairs into male and female. This activity may be correlated with the reduction in egg production, since 1 and 3 showed better inhibitory properties compared with 2 and 4. PMID:20158148

  8. Characterization of the O- and N-linked oligosaccharides in glycoproteins synthesized by Schistosoma mansoni

    International Nuclear Information System (INIS)

    The structures of the O- and N-linked oligosaccharides in glycoproteins synthesized by larval and adult schistosomes of Schistosoma mansoni have been investigated. Mechanically transformed schistosomula or adult schistosomes were incubated in media containing either [3H]mannose, [3H]glucosamine or [3H]galactose for 48 and 24 hr, respectively, to radiolabel metabolically the oligosaccharide moieties of newly synthesized glycoproteins. Analyses of the radiolabeled glycoproteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE) and fluorography demonstrated that numerous glycoproteins from 48-hr old schistosomula and adult schistosomes were labeled by both the [3H]mannose and [3H]glucosamine precursors. The [3H]galactose precursor was incorporated into numerous glycoproteins in adult schistosomes; however, few, if any, glycoproteins in schistosomula were labeled by this radioactive sugar precursor

  9. [Myeloradiculitis due to Schistosoma haematobium: about an observation in Dakar (Senegal)].

    Science.gov (United States)

    Boubacar, S; Diagne, N S; Ben Adji, D W; Diop, A M; Seydi, M; Maiga, Y; Toure, K; Ndiaye, M; Diop, A G; Ndiaye, M M

    2016-05-01

    Nervous localisations of schistosomiasis are rare. We report the case of a 25 year-old Senegalese patient admitted for a progressive myeloradiculitis onset, over a one week period. The diagnosis of Schistosoma haematobium myeloradiculitis was made in front of a positive serum serology for S. haematobium, presence of S. haematobium eggs in urine, hyperproteinorachia, endemicity of S. haematobium in the region where the patient was originating and a past medical history of macroscopic hematuria in a context of river bathing. There was also no arguments for another cause to these neurological manifestations. Our patient was treated with praziquantel, prednisone and physiotherapy. Evolution was marked 6 weeks after the beginning of treatment by a significant improvement of motor deficit, enabling the patient to walk again. There was also a regression of genitosphincter dysfunction. Work-up for patients presenting with paraplegia in tropical countries, should also include search for S. heamatobium infection. PMID:26936766

  10. Structural basis for selective inhibition of purine nucleoside phosphorylase from Schistosoma mansoni: kinetic and structural studies.

    Science.gov (United States)

    Castilho, Marcelo S; Postigo, Matheus P; Pereira, Humberto M; Oliva, Glaucius; Andricopulo, Adriano D

    2010-02-15

    Selectivity plays a crucial role in the design of enzyme inhibitors as novel antiparasitic agents, particularly in cases where the target enzyme is also present in the human host. Purine nucleoside phosphorylase from Schistosoma mansoni (SmPNP) is an attractive target for the discovery of potential antischistosomal agents. In the present work, kinetic studies were carried out in order to determine the inhibitory potency, mode of action and enzyme selectivity of a series of inhibitors of SmPNP. In addition, crystallographic studies provided important structural insights for rational inhibitor design, revealing consistent structural differences in the binding mode of the inhibitors in the active sites of the SmPNP and human PNP (HsPNP) structures. The molecular information gathered in this work should be useful for future medicinal chemistry efforts in the design of new inhibitors of SmPNP having increased affinity and selectivity. PMID:20129792

  11. Crystallization and X-ray analysis of the Schistosoma mansoni guanidino kinase

    International Nuclear Information System (INIS)

    The X-ray structure of the guanidino kinase from S. mansoni has been determined at 2.8 Å resolution by the molecular-replacement method. The 716-amino-acid guanidino kinase from the parasitic flatworm Schistosoma mansoni results from the fusion of two guanidino kinase subunits. Crystals of this 80 kDa protein have been obtained in the monoclinic space group P21, with unit-cell parameters a = 52.7, b = 122.1, c = 63.2 Å, β = 108.5°. Synchrotron data were collected to 2.8 Å resolution on ESRF beamline ID29. The structure was solved by the molecular-replacement method, using the 357-amino-acid structure of the arginine kinase from Trypanosoma cruzi as the search model

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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. 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

  15. Identification of Candidate Serum Biomarkers for Schistosoma mansoni Infected Mice Using Multiple Proteomic Platforms

    Science.gov (United States)

    Kardoush, Manal I.

    2016-01-01

    Background Schistosomiasis is an important helminth infection of humans. There are few reliable diagnostic biomarkers for early infection, for recurrent infection or to document successful treatment. In this study, we compared serum protein profiles in uninfected and infected mice to identify disease stage-specific biomarkers. Methods Serum collected from CD1 mice infected with 50–200 Schistosoma mansoni cercariae were analyzed before infection and at 3, 6 and 12 weeks post-infection using three mass spectrometric (MS) platforms. Results Using SELDI-TOF MS, 66 discriminating m/z peaks were detected between S. mansoni infected mice and healthy controls. Used in various combinations, these peaks could 1) reliably diagnose early-stage disease, 2) distinguish between acute and chronic infection and 3) diagnose S. mansoni infection regardless the parasite burden. The most important contributors to these diagnostic algorithms were peaks at 3.7, 13 and 46 kDa. Employing sample fractionation and differential gel electrophoresis, we analyzed gel slices either by MALDI-TOF MS or Velos Orbitrap MS. The former yielded eight differentially-expressed host proteins in the serum at different disease stages including transferrin and alpha 1- antitrypsin. The latter suggested the presence of a surprising number of parasite-origin proteins in the serum during both the acute (n = 200) and chronic (n = 105) stages. The Orbitrap platform also identified many differentially-expressed host-origin serum proteins during the acute and chronic stages (296 and 220 respectively). The presence of one of the schistosome proteins, glutathione S transferase (GST: 25 KDa), was confirmed by Western Blot. This study provides proof-of-principle for an approach that can yield a large number of novel candidate biomarkers for Schistosoma infection. PMID:27138990

  16. NCCN Evidence Blocks.

    Science.gov (United States)

    Carlson, Robert W; Jonasch, Eric

    2016-05-01

    NCCN has developed a series of Evidence Blocks: graphics that provide ratings for each recommended treatment regimen in terms of efficacy, toxicity, quality and consistency of the supporting data, and affordability. The NCCN Evidence Blocks are currently available in 10 tumor types within the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines). At a glance, patients and providers can understand how a given treatment was assessed by the NCCN Guidelines Panel and get a sense of how a given treatment may match individual needs and preferences. Robert W. Carlson, MD, CEO of NCCN, described the reasoning behind this new feature and how the tool is used, and Eric Jonasch, MD, Professor of Genitourinary Medical Oncology at The University of Texas MD Anderson Cancer Center, and Vice Chair of the NCCN Kidney Cancer Panel, described its applicability in the management of metastatic renal cell carcinoma. PMID:27226499

  17. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse;

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included in...... men vs. 0.5%/2.3% in women, P <0.001). Significant predictors of newly acquired RBBB were male gender, increasing age, high systolic blood pressure, and presence of IRBBB, whereas predictors of newly acquired IRBBB were male gender, increasing age, and low BMI. Right bundle branch block was associated...... with significantly increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch...

  18. SNUPPS power block modelling

    International Nuclear Information System (INIS)

    A series of models is being built and used as tools in the design of the SNUPPS Standard Power Block. The modelling programme includes both preliminary and final design models, a construction sequence mode, and additional models used to study various features of the design. The design of a standard power block unit has necessitated design definition which is more detailed than that customarily used in the design of nuclear power stations. One innovation is the use of engineering models as a primary design tool in the layout of process piping, preparation of isometric drawings, design of small components which are customarily designed in the field during construction. Development of a standard construction sequence and construction work plan is another innovation. (author)

  19. SUPERFICIAL CERVICAL PLEXUS BLOCK

    Directory of Open Access Journals (Sweden)

    Komang Mega Puspadisari

    2014-01-01

    Full Text Available Superficial cervical plexus block is one of the regional anesthesia in  neck were limited to thesuperficial fascia. Anesthesia is used to relieve pain caused either during or after the surgery iscompleted. This technique can be done by landmark or with ultrasound guiding. The midpointof posterior border of the Sternocleidomastoid was identified and the prosedure done on thatplace or on the level of cartilage cricoid.

  20. Growth, Endlessness, Blocks

    OpenAIRE

    Nabata, Avery Misuzu

    2014-01-01

    Growth, Endlessness, Blocks is a sculptural installation comprised of a series of wood structures of various scales. Large sections of drywall function as extensions of the gallery walls. Each structure balances a number of different physical characteristics that are tied to the act of making. Balance and presence combine in a disconcerting way giving the viewer a sense of uneasiness and a moment finely tuned by the artist. The artist seeks to embody the role of the factory fabricator as a me...

  1. Migration and survival of gamma-irradiated Schistosoma mansoni larvae and the duration of host-parasite contact in relation to the induction of resistance in mice

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, B.L.; Dean, D.A.

    1984-01-01

    The migration in mice of 20-, 50-, and 90-krad /sup 60/Co-irradiated Schistosoma mansoni larvae, biosynthetically radioisotope labeled with /sup 75/Se-selenomethionine, was evaluated by autoradiography of compressed tissues and compared to the migration of non-irradiated 75 Se-labeled larvae. By day 8 over 90% of both non-irradiated and 20 krad-irradiated organisms were located in the lungs. In contrast to non-irradiated organisms, however, only a small proportion of 20-krad organisms migrated to the liver. The delay in migration between skin and lungs was more pronounced with 50-krad-irradiated schistosomula. No more than an occasional 50-krad-irradiated organism was ever detected in the liver. In three experiments, over 85% of the 90-krad-irradiated organisms were retained in the skin; in a fourth experiment about half of the 90-krad-irradiated organisms migrated as far as the lungs. Only an occasional 90-krad organism was ever detected in the liver. In three experiments, over 85% of the 90 Krad.-irradiated organisms were retained in the skin, in a fourth experiment about half of the 90 Krad.-irradiated organisms migrated as far as the lungs. Only an occasional 90 Krad. organism was ever detected in the liver. Removal of the skin exposure site within the first 4 days of immunization with either 50- or 90-krad-irradiated cercariae completely blocked the induction of resistance. Removal between the 4th and the 6th days gave variable results.

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Schistosoma mansoni venom allergen-like protein 4 (SmVAL4) is a novel lipid-binding SCP/TAPS protein that lacks the prototypical CAP motifs

    Energy Technology Data Exchange (ETDEWEB)

    Kelleher, Alan [Baylor College of Medicine, Houston, TX 77030 (United States); Darwiche, Rabih [University of Fribourg, Chemin du Musée 10, CH 1700 Fribourg (Switzerland); Rezende, Wanderson C. [Baylor College of Medicine, Houston, TX 77030 (United States); Farias, Leonardo P.; Leite, Luciana C. C. [Instituto Butantan, São Paulo, SP (Brazil); Schneiter, Roger [University of Fribourg, Chemin du Musée 10, CH 1700 Fribourg (Switzerland); Asojo, Oluwatoyin A., E-mail: asojo@bcm.edu [Baylor College of Medicine, Houston, TX 77030 (United States)

    2014-08-01

    The first structure of an S. mansoni venom allergen-like protein is presented. Schistosomiasis is a parasitic disease that affects over 200 million people. Vaccine candidates have been identified, including Schistosoma mansoni venom allergen-like proteins (SmVALs) from the SCP/TAPS (sperm-coating protein/Tpx/antigen 5/pathogenesis related-1/Sc7) superfamily. The first SmVAL structure, SmVAL4, was refined to a resolution limit of 2.16 Å. SmVAL4 has a unique structure that could not be predicted from homologous structures, with longer loops and an unusual C-terminal extension. SmVAL4 has the characteristic α/β-sandwich and central SCP/TAPS cavity. Furthermore, SmVAL4 has only one of the signature CAP cavity tetrad amino-acid residues and is missing the histidines that coordinate divalent cations such as Zn{sup 2+} in other SCP/TAPS proteins. SmVAL4 has a cavity between α-helices 1 and 4 that was observed to bind lipids in tablysin-15, suggesting the ability to bind lipids. Subsequently, SmVAL4 was shown to bind cholesterol in vitro. Additionally, SmVAL4 was shown to complement the in vivo sterol-export phenotype of yeast mutants lacking their endogenous CAP proteins. Expression of SmVAL4 in yeast cells lacking endogenous CAP function restores the block in sterol export. These studies suggest an evolutionarily conserved lipid-binding function shared by CAP proteins such as SmVAL4 and yeast CAP proteins such as Pry1.

  4. Schistosoma mansoni venom allergen-like protein 4 (SmVAL4) is a novel lipid-binding SCP/TAPS protein that lacks the prototypical CAP motifs

    International Nuclear Information System (INIS)

    The first structure of an S. mansoni venom allergen-like protein is presented. Schistosomiasis is a parasitic disease that affects over 200 million people. Vaccine candidates have been identified, including Schistosoma mansoni venom allergen-like proteins (SmVALs) from the SCP/TAPS (sperm-coating protein/Tpx/antigen 5/pathogenesis related-1/Sc7) superfamily. The first SmVAL structure, SmVAL4, was refined to a resolution limit of 2.16 Å. SmVAL4 has a unique structure that could not be predicted from homologous structures, with longer loops and an unusual C-terminal extension. SmVAL4 has the characteristic α/β-sandwich and central SCP/TAPS cavity. Furthermore, SmVAL4 has only one of the signature CAP cavity tetrad amino-acid residues and is missing the histidines that coordinate divalent cations such as Zn2+ in other SCP/TAPS proteins. SmVAL4 has a cavity between α-helices 1 and 4 that was observed to bind lipids in tablysin-15, suggesting the ability to bind lipids. Subsequently, SmVAL4 was shown to bind cholesterol in vitro. Additionally, SmVAL4 was shown to complement the in vivo sterol-export phenotype of yeast mutants lacking their endogenous CAP proteins. Expression of SmVAL4 in yeast cells lacking endogenous CAP function restores the block in sterol export. These studies suggest an evolutionarily conserved lipid-binding function shared by CAP proteins such as SmVAL4 and yeast CAP proteins such as Pry1

  5. E-Block: A Tangible Programming Tool with Graphical Blocks

    Directory of Open Access Journals (Sweden)

    Danli Wang

    2013-01-01

    Full Text Available This paper designs a tangible programming tool, E-Block, for children aged 5 to 9 to experience the preliminary understanding of programming by building blocks. With embedded artificial intelligence, the tool defines the programming blocks with the sensors as the input and enables children to write programs to complete the tasks in the computer. The symbol on the programming block's surface is used to help children understanding the function of each block. The sequence information is transferred to computer by microcomputers and then translated into semantic information. The system applies wireless and infrared technologies and provides user with feedbacks on both screen and programming blocks. Preliminary user studies using observation and user interview methods are shown for E-Block's prototype. The test results prove that E-Block is attractive to children and easy to learn and use. The project also highlights potential advantages of using single chip microcomputer (SCM technology to develop tangible programming tools for children.

  6. 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...

  7. Effect of Ketoconazole, a Cytochrome P450 Inhibitor, on the Efficacy of Quinine and Halofantrine against Schistosoma mansoni in Mice

    OpenAIRE

    Seif el-Din, Sayed Hassan; Sabra, Abdel-Nasser Abdel-Aal; Hammam, Olfat Ali; El-Lakkany, Naglaa Mohamed

    2013-01-01

    The fear that schistosomes will become resistant to praziquantel (PZQ) motivates the search for alternatives to treat schistosomiasis. The antimalarials quinine (QN) and halofantrine (HF) possess moderate antischistosomal properties. The major metabolic pathway of QN and HF is through cytochrome P450 (CYP) 3A4. Accordingly, this study investigates the effects of CYP3A4 inhibitor, ketoconazole (KTZ), on the antischistosomal potential of these quinolines against Schistosoma mansoni infection by...

  8. Acetylcholinesterase of Schistosoma mansoni--functional correlates. Contributed in honor of Professor Hans Neurath's 90th birthday.

    OpenAIRE

    Arnon, R; Silman, I.; Tarrab-Hazdai, R

    1999-01-01

    Acetylcholinesterase (AChE) is an enzyme broadly distributed in many species, including parasites. It occurs in multiple molecular forms that differ in their quaternary structure and mode of anchoring to the cell surface. This review summarizes biochemical and immunological investigations carried out in our laboratories on AChE of the helmint, Schistosoma mansoni. AChE appears in S. mansoni in two principal molecular forms, both globular, with sedimentation coefficients of approximately 6.5 a...

  9. Candidate vaccine antigens identified by antibodies from mice vaccinated with 15- or 50-kilorad-irradiated cercariae of Schistosoma mansoni.

    OpenAIRE

    Richter, D.; Harn, D A

    1993-01-01

    In murine schistosomiasis, the highest levels of resistance to cercarial challenge are obtained by vaccination with radiation-attenuated cercariae. To identify candidate vaccine antigens relevant to the vaccine model, we examined parasite antigens recognized by antibodies from mice vaccinated with irradiated cercariae of Schistosoma mansoni. To optimize recognition of a wide spectrum of antigens, several factors that influence the level of protection in this model were varied; specifically, w...

  10. Penetration of human skin by the cercariae of Schistosoma mansoni: an investigation of the effect of multiple cercarial applications.

    OpenAIRE

    Ingram, Rebecca; Bartlett, A; Brown, M. B.; C Marriott; Whitfield, P. J.

    2003-01-01

    It has previously been postulated that L-arginine emitted by penetrating Schistosoma mansoni cercariae serves as an intraspecific signal guiding other cercariae to the penetration site. It was suggested that penetrating in groups offers a selective advantage. If this hypothesis is correct and group penetration at one site on the host offers an advantage, it would follow that at such a site, successive groups of cercariae would be able to penetrate skin in either greater numbers or at a faster...

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

    OpenAIRE

    Machado-Silva José Roberto; Silva Cléber Hooper da; Pereira Mário José dos Santos; Oliveira Regina Maria Figueiredo de; Pinto Roberto Magalhães; Gomes Delir Corrêa

    2000-01-01

    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 i...

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

    OpenAIRE

    2002-01-01

    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. Nevertheles...

  13. 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...

  14. Schistosoma haematobium Infection and CD4+ T-Cell Levels: A Cross-Sectional Study of Young South African Women

    OpenAIRE

    Kleppa, Elisabeth; Klinge, Kari Furseth; Galappaththi-Arachchige, Hashini Nilushika; Holmen, Sigve; Lillebø, Kristine; Onsrud, Mathias; Gundersen, Svein Gunnar; Taylor, Myra; Ndhlovu, Patricia D; Kjetland, Eyrun Floerecke

    2015-01-01

    Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated...

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

    OpenAIRE

    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 ...

  16. Differential anti-glycan antibody responses in Schistosoma mansoni-infected children and adults studied by shotgun glycan microarray.

    Directory of Open Access Journals (Sweden)

    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

  17. 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...

  18. Oxamniquine cures Schistosoma mansoni infection in a focus in which cure rates with praziquantel are unusually low

    OpenAIRE

    Stelma, F.F.; Sall, S.; Daff, B.; Sow, S; Niang, M; Gryseels, B.

    1997-01-01

    An outbreak of Schistosoma mansoni in northern Senegal was observed in 1988, and chemotherapy with praziquantel in this recently established focus resulted in very low parasitologic cure rates. Among other explanations, the emergence of a praziquantel-tolerant parasite strain was feared. To study this hypothesis further, 138 persons with endemic S. mansoni infection were randomly allocated to treatment with either 20 mg/kg oxamniquine or 40 mg/kg praziquantel. Parasitologic cure rates at 6 we...

  19. Praziquantel, Mefloquine-Praziquantel, and Mefloquine-Artesunate-Praziquantel against Schistosoma haematobium: A Randomized, Exploratory, Open-Label Trial

    OpenAIRE

    Keiser, Jennifer; Silué, Kigbafori D; Adiossan, Lukas K.; N'Guessan, Nicaise A.; Monsan, N'Chou; Utzinger, Jürg; N'Goran, Eliézer K.

    2014-01-01

    Background Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel. Hence, there is a pressing need to develop additional therapeutics against schistosomiasis. The antimalarial drug mefloquine shows antischistosomal activity in animal models and clinical trials, which calls for further investigations. Methodology We comparatively assessed the efficacy and tolerability of the following treatments against Schistosoma haematobium in school-aged children in Côte d...

  20. Schistosoma mansoni Larvae Do Not Expand or Activate Foxp3+ Regulatory T Cells during Their Migratory Phase

    OpenAIRE

    Redpath, Stephen A.; van der Werf, Nienke; MacDonald, Andrew S; Maizels, Rick M.; Taylor, Matthew D.

    2015-01-01

    Foxp3+ regulatory T (Treg) cells play a key role in suppression of immune responses during parasitic helminth infection, both by controlling damaging immunopathology and by inhibiting protective immunity. During the patent phase of Schistosoma mansoni infection, Foxp3+ Treg cells are activated and suppress egg-elicited Th2 responses, but little is known of their induction and role during the early prepatent larval stage of infection. We quantified Foxp3+ Treg cell responses during the first 3...

  1. Differences in immunogenicity and vaccine potential of peptides from .I.Schistosoma mansoni./I. glyceraldehyde 3-phosphate dehydrogenase

    Czech Academy of Sciences Publication Activity Database

    Tallima, H.; Montash, M.; Vepřek, Pavel; Velek, Jiří; Ježek, Jan; El Ridi, R.

    2003-01-01

    Roč. 21, - (2003), s. 3290-3300. ISSN 0264-410X R&D Projects: GA ČR GA303/01/0690 Grant ostatní: ICGEB(IT) CRP/EGY98-03 Institutional research plan: CEZ:AV0Z4055905 Keywords : .I.Schistosoma mansoni./I. * glyceraldehyde 3-phosphate dehydrogenase * synthetic peptide vaccine Subject RIV: CC - Organic Chemistry Impact factor: 3.007, year: 2003

  2. Evaluating the potential impact of mass praziquantel administration for HIV prevention in schistosoma haematobium high-risk communities

    OpenAIRE

    Mbah, Martial L Ndeffo; Gilbert, Jennifer A.; Galvani, Alison P.

    2014-01-01

    Genital infection with Schistosoma haematobium is prevalent in sub-Saharan Africa. Epidemiological studies have observed that genital schistosomiasis is associated with an increased odd of HIV infection among women. We used mathematical modeling to explore the potential impact of mass preventive chemotherapy against schistosomiasis on HIV transmission in three sub-Saharan Africa countries: Angola, Kenya, and Zambia. We developed a model of female genital schistosomiasis (FGS) and HIV transmis...

  3. Sonographic screening for urinary tract abnormalities in patients with Schistosoma haematobium infection: pitfalls in examining pregnant women.

    OpenAIRE

    Richter, J; Wagatsuma, Y; Aryeetey, M.; Feldmeier, H.

    1996-01-01

    In areas where Schistosoma haematobium is endemic, urinary schistosomiasis and pregnancy are frequently concomitant; however, both these conditions may produce similar urinary tract changes in ultrasound scans and hence their differential diagnosis may be difficult. In patients with urinary schistosomiasis, focal and/or diffuse urinary bladder wall changes are frequently detected ultrasonically. Dilatation of one or both ureters and progressive hydronephrosis may be observed in more severe ca...

  4. 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

    Directory of Open Access Journals (Sweden)

    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

  5. Development of Schistosoma mansoni in Biomphalaria tenagophila, Biomphalaria straminea and Biomphalaria glabrata Desenvolvimento do Schistosoma mansoni em Biomphalaria tenagophila, Biomphalaria straminea e Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    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

  6. Demographic Data - MDC_Block

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — A polygon feature class of Miami-Dade Census 2000 Blocks. Census blocks are areas bounded on all sides by visible and/or invisible features shown on a map prepared...

  7. Ear - blocked at high altitudes

    Science.gov (United States)

    High altitudes and blocked ears; Flying and blocked ears; Eustachian tube dysfunction - high altitude ... you are going up or coming down from high altitudes. Chewing gum the entire time you are changing ...

  8. Respuesta diferencial de variedades de soya a la asociación simbiótica con cepas de Bradyrhizobium japonicum, en Oxisoles de la Orinoquia colombiana / Differental response of soybean varieties to the symbiotic association with Bradyrhizobium japonicum strains, in Oxisols of the Colombian Orinoquia

    OpenAIRE

    Valencia Ramírez, Rubén Alfredo

    2010-01-01

    El cultivo de la soya (Glycine max (L) Merril), en oxisoles de la Orinoquia colombiana presenta restricciones por la alta saturación de aluminio y en general, baja CIC y MO, que afectan la fijación biológica del N y el crecimiento normal de las plantas. La respuesta diferencial de variedades de soya a la inoculación con diferentes cepas de B. japonicum, se determinó mediante la evaluación de seis genotipos inoculados individualmente con las cepas ICA J-01, J-96, J-98, la mezcla de J-01 con J-...

  9. Schistosoma mansoni

    DEFF Research Database (Denmark)

    Friis, Henrik; Byskov, Jens

    1987-01-01

    splenomegaly. 80.5% of the children examined parasitologically were found infected. Among these the arithmetric mean egg output was 744.7 and the geometric mean 307.3 eggs per gram of faeces (epg), 46.0% were excreting more than 400 epg. 23 children were found to have an enlarged liver, whereas none was found...... with enlarged spleen. 21 of these had schistosomiasis. The prevalence of hepatomegaly was highest among those excreting above 1600 epg. Also the mean size of the enlarged livers increased with intensity of infection....

  10. Porous block nanofiber composite filters

    Energy Technology Data Exchange (ETDEWEB)

    Ginley, David S.; Curtis, Calvin J.; Miedaner, Alexander; Weiss, Alan J.; Paddock, Arnold

    2016-08-09

    Porous block nano-fiber composite (110), a filtration system (10) and methods of using the same are disclosed. An exemplary porous block nano-fiber composite (110) includes a porous block (100) having one or more pores (200). The porous block nano-fiber composite (110) also includes a plurality of inorganic nano-fibers (211) formed within at least one of the pores (200).

  11. Dicty_cDB: SHB650 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 CV682907 |CV682907.1 service43_H06_sjs2-16-2B11-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 9e-04... 1 CV682854 |CV682854.1 service30_G09_sjs2-14-10C09-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 9e-... CV688215 |CV688215.1 sjs2-16-2_G01_sjs2-16-2G01-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 9e-04

  12. Dicty_cDB: SHG508 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 1 CV682854 |CV682854.1 service30_G09_sjs2-14-10C09-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.... 1 CV682907 |CV682907.1 service43_H06_sjs2-16-2B11-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.00...1 CV688215 |CV688215.1 sjs2-16-2_G01_sjs2-16-2G01-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001

  13. Dicty_cDB: SHE841 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ice43_H06_sjs2-16-2B11-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001 1 CV682854 |CV682854.1 ser...V688215 |CV688215.1 sjs2-16-2_G01_sjs2-16-2G01-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001 1 CV682907 |CV682907.1 serv...vice30_G09_sjs2-14-10C09-T3 SJS Schistosoma japonicum cDNA, mRNA sequence. 56 0.001

  14. Dicty_cDB: SFA668 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SF (Link to library) SFA668 (Link to dictyBase) - - - Contig-U12091-1 SFA668P (Link to Original ... hmvnsmmvivisfyillkkvihlnmifisf*vlllpkmklalllik qln*mis *vvhqfnivnvnhmkvqafyhysqnisfyqvvlnqdlimlnqqninqdyyi ... N313917_1( FN313917 |pid:none) Schistosoma japonicum is olate Anhu... 167 6e-57 EU334660_1( EU334660 |pid: ... N317120_1( FN317120 |pid:none) Schistosoma japonicum is olate Anhu... 166 1e-55 FN316954_1( FN316954 |pid: ... none) Schistosoma japonicum is olate Anhu... 165 2e-55 AB071136_1( AB071136 |pid: ...

  15. A standard graphite block

    International Nuclear Information System (INIS)

    A graphite block was calibrated for the thermal neutron flux of the Ra-Be source using indium foils as detectors. Experimental values of the thermal neutron flux along the central vertical axis of the system were corrected for the self-shielding effect and depression of flux in the detector. The experimental values obtained were compared with the values calculated on the basis of solving the conservation neutron equation by the continuous slowing-down theory. In this theoretical calculation of the flux the Ra-Be source was divided into three resonance energy regions. The measurement of the thermal neutron diffusion length in the standard graphite block is described. The measurements were performed in the thermal neutron region of the system. The experimental results were interpreted by the diffusion theory for point thermal neutron source in the finite system. The thermal neutron diffusion length was calculated to be L= 50.9 ±3.1 cm for the following graphite characteristics: density = 1.7 g/cm3; boron content = 0.1 ppm; absorption cross section = 3.7 mb

  16. One-Block CYRCA: an automated procedure for identifying multiple-block alignments from single block queries

    OpenAIRE

    Frenkel-Morgenstern, Milana; Singer, Alice; Bronfeld, Hagit; Pietrokovski, Shmuel

    2005-01-01

    One-Block CYRCA is an automated procedure for identifying multiple-block alignments from single block queries (). It is based on the LAMA and CYRCA block-to-block alignment methods. The procedure identifies whether the query blocks can form new multiple-block alignments (block sets) with blocks from a database or join pre-existing database block sets. Using pre-computed LAMA block alignments and CYRCA sets from the Blocks database reduces the computation time. LAMA and CYRCA are highly sensit...

  17. RESISTANCE TO OXAMNIQUINE OF A Schistosoma mansoni STRAIN ISOLATED FROM PATIENT SUBMITTED TO REPEATED TREATMENTS

    Directory of Open Access Journals (Sweden)

    M.Z. COELHO

    1997-03-01

    Full Text Available A strain of Schistosoma mansoni (R1 was isolated from patient previously submitted to four treatments with oxamniquine, and to another one with praziquantel. The results obtained with chemotherapeutic test, by using oxamniquine in mice infected with the strains R1 and LE (standard, showed an evident resistance to the drug in worms of the strain R1. Thus, at the dose of 250 mg/kg oxamniquine, all mice (17 infected with the LE strain did not show surviving worms, whereas 12 out of 17 mice infected with the R1 strain presented surviving worms. At the dose of 200 mg/kg, the LE strain showed recovery rates of 1.06% and 20.58%, whereas the R1 strain presented 18.57% and 61.14%, for male and female worms, respectively. At the dose of 100 mg/kg, the recovery of male worms was 2.6% for the LE strain, and 29.9% for the R1 strain. At the same dose, the recovery of females did not show statistically significant differences between the two strains (LE = 76.38%, R1 = 79.12%. Praziquantel showed similar antischistosomal activity against both studied strains, when administered at the dose of 500 mg/kgResistência ao oxamniquine de uma cepa de Schistosoma mansoni isolada de paciente submetido a repetidos tratamentos Uma cepa de Schistosoma mansoni (R1 foi isolada de paciente previamente submetido a quatro tratamentos com oxamniquine e a um outro com praziquantel. Os resultados obtidos com o teste quimioterapêutico, usando oxamniquine em camundongos infectados com as cepas R1 e LE (padrão mostraram resistência evidente à droga em vermes de cepa R1. Assim, com a dose de 250 mg/kg de oxamniquine, todos os camundongos (17 dos 17 camundongos infectados com a cepa R1 apresentaram vermes sobreviventes. Com a dosagem de 200 mg/kg a cepa LE mostrou taxas de recuperação de 1,06 e 20,58% enquanto a cepa R1 apresentou 18,57 e 61,14% para os vermes machos e fêmeas, respectivamente. Com a dose de 100 mg/kg a recuperação de vermes machos foi de 2,6% para a Cepa LE e

  18. Effect of pH on tritium exchange and hydrogen production and uptake in free-living cells and in bacteroids of Bradyrhizobium japonicum

    International Nuclear Information System (INIS)

    Soybean nodule bacteroids and Bradyrhizobium japonicum free-living cells induced for H2-uptake hydrogenase, actively catalyze the evolution of H2 in a reaction highly dependent on the pH. The optimal pHs for the evolution and uptake reactions were 4.0 and 7.5-8.0, respectively. No differences were found between free-living cells and bacteroids with respect to hydrogen acceptor specificity, although absolute rates of H2 uptake were higher for free-living cells. Both types of cells were able to evolve hydrogen from reduced methyl viologen at low pH. These intact cells also catalyzed the exchange reaction between tritium and water in the absence of oxygen. The pH profile of the exchange activity showed two peaks at values near the optimal pHs for the evolution and uptake reactions

  19. Labeling of carbon pools in Bradyrhizobium japonicum and Rhizobium leguminosarum bv viciae bacteroids following incubation of intact nodules with 14CO2

    International Nuclear Information System (INIS)

    The aim of the work reported here was to ascertain that the patterns of labeling seen in isolated bacteroids also occurred in bacteroids in intact nodules and to observe early metabolic events following exposure of intact nodules to 14CO2. Intact nodules of soybean (Glycine max L. Merr. cv Ripley) inoculated with Bradyrhizobium japonicum USDA 110 and pea (Pisum sativum L. cv Progress 9) inoculated with Rhizobium leguminosarum by viciae isolate 128C53 were detached and immediately fed 14CO2 for 1 to 6 min. Bacteroids were purified from these nodules in 5 to 7 min after the feeding period. In the cytosol from both soybean and pea nodules, malate had the highest radioactivity, followed by citrate and aspartate. In peas, asparagine labeling equaled that of aspartate. In B. japonicum bacteroids, malate was the most rapidly labeled compound, and the rate of glutamate labeling was 67% of the rate of malate labeling. Aspartate and alanine were the next most rapidly labeled compounds. R. leguminosarum bacteroids had very low amounts of 14C and, after a 1-min feeding, malate contained 90% of the radioactivity in the organic acid fraction. Only a trace of activity was found in aspartate, whereas the rate of glutamate and alanine labeling approached that of malate after 6 min of feeding. Under the conditions studied, malate was the major form of labeled carbon supplied to both types of bacteroids. These results with intact nodules confirm our earlier results with isolated bacteroids, which showed that a significant proportion of provided labeled substrate, such as malate, is diverted to glutamate. This supports the conclusion that microaerobic conditions in nodules influence carbon metabolism in bacteroids. (author)

  20. Blocking the Hawking radiation

    DEFF Research Database (Denmark)

    Autzen, M.; Kouvaris, C.

    2014-01-01

    grows after its formation (and eventually destroys the star) instead of evaporating. The fate of the black hole is dictated by the two opposite mechanics, i.e., accretion of nuclear matter from the center of the star and Hawking radiation that tends to decrease the mass of the black hole. We study how......Some severe constraints on asymmetric dark matter are based on the scenario that certain types of weakly interacting massive particles can form mini-black holes inside neutron stars that can lead to their destruction. A crucial element for the realization of this scenario is that the black hole...... the assumptions for the accretion rate can in fact affect the critical mass beyond which a black hole always grows. We also study to what extent degenerate nuclear matter can impede Hawking radiation due to the fact that emitted particles can be Pauli blocked at the core of the star....

  1. Photovoltaic building blocks

    DEFF Research Database (Denmark)

    Hanberg, Peter Jesper; Jørgensen, Anders Michael

    2014-01-01

    efficiency of about 15% for commercial Silicon solar cells there is still much to gain. DTU Danchip provides research facilities, equipment and expertise for the building blocks that comprises fabricating the efficient solar cell. In order to get more of the sun light into the device we provide thin film...... coating tools to depositand develop anti-reflection filters by means of sputtering or e-beam evaporation. To reduce the area taken up by metallic contacts transparent conducting oxides like Aluminium doped ZincOxide (AZO) and Indium Tin Oxide (ITO) can be deposited. We also support research...... and development of new 2D materials like graphene that is a promising candidate for cheap highly transparent contacts. Another way to increase efficiency is to structure the active layers indevice so that more light is absorbed. This can be done in one of our advanced dry etching machines either mask-less to form...

  2. Block Voter Model

    CERN Document Server

    Sampaio, C I N

    2011-01-01

    We introduce and study the block voter model with noise on two-dimensional square lattices using Monte Carlo simulations and finite-size scaling techniques. The model is defined by an outflow dynamics where a central set of $N_{PCS}$ spins, here denoted by persuasive cluster spins (PCS), tries to influence the opinion of their neighbouring counterparts. We consider the collective behaviour of the entire system with varying PCS size. When $N_{PCS}>2$, the system exhibits an order-disorder phase transition at a critical noise parameter $q_{c}$ which is a monotonically increasing function of the size of the persuasive cluster. We conclude that how large the PCS is more power of persuasion it has. It also seems that the resulting critical behaviour is Ising-like independent of the range of the interactions.

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

    Directory of Open Access Journals (Sweden)

    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

  4. Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Schistosomiasis and pulmonary arterial hypertension

    OpenAIRE

    Ghazwan Butrous

    2014-01-01

    Schistosomiasis is caused by infection with the parasite Schistosoma, which is a flat-worm or fluke. The dominant species are Schistosoma mansoni, Schistosoma japonicum, and Schistosoma haematobium. Schistosomiasis is the third most common parasitic disease in the world after malaria and amoebiasis. It is endemic in more than 70 countries affecting about 200 million people worldwide, of whom 80% are in sub-Saharan Africa. There are pockets of infection in north-eastern Brazil, near the Yangtz...

  5. Why the radiation-attenuated cercarial immunization studies failed to guide the road for an effective schistosomiasis vaccine: A review

    OpenAIRE

    Rashika El Ridi; Hatem Tallima

    2014-01-01

    Schistosomiasis is a debilitating parasitic disease caused by platyhelminthes of the genus Schistosoma, notably Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum. Pioneer researchers used radiation-attenuated (RA) schistosome larvae to immunize laboratory rodent and non-human primate hosts. Significant and reproducible reduction in challenge worm burden varying from 30% to 90% was achieved, providing a sound proof that vaccination against this infection is feasible. Exte...

  6. The Block-block Bootstrap: Improved Asymptotic Refinements

    OpenAIRE

    Donald W.K. Andrews

    2002-01-01

    The asymptotic refinements attributable to the block bootstrap for time series are not as large as those of the nonparametric iid bootstrap or the parametric bootstrap. One reason is that the independence between the blocks in the block bootstrap sample does not mimic the dependence structure of the original sample. This is the join-point problem. In this paper, we propose a method of solving this problem. The idea is not to alter the block bootstrap. Instead, we alter the original sample sta...

  7. Convergence rates of empirical block length selectors for block bootstrap

    OpenAIRE

    Nordman, Daniel J.; Lahiri, Soumendra N.

    2014-01-01

    We investigate the accuracy of two general non-parametric methods for estimating optimal block lengths for block bootstraps with time series – the first proposed in the seminal paper of Hall, Horowitz and Jing (Biometrika 82 (1995) 561–574) and the second from Lahiri et al. (Stat. Methodol. 4 (2007) 292–321). The relative performances of these general methods have been unknown and, to provide a comparison, we focus on rates of convergence for these block length selectors for the moving block ...

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

    Directory of Open Access Journals (Sweden)

    Sheilla A Oliveira

    2003-07-01

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Genetic markers between Biomphalaria glabrata snails susceptible and resistant to Schistosoma mansoni infection

    Directory of Open Access Journals (Sweden)

    RGM Spada

    2002-10-01

    Full Text Available The analysis of the genetic variability related to susceptibility to Schistosoma mansoni infection in the vector of the genus Biomphalaria is important in terms of a better understanding of the epidemiology of schistosomiasis itself, the possible pathological implications of this interaction in vertebrate hosts, and the formulation of new strategies and approaches for disease control. In the present study, the genetic variability of B. glabrata strains found to be resistant or susceptible to S. mansoni infection was investigated using DNA amplification by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR. The amplification products were analyzed on 8% polyacrylamide gel and stained with silver. We selected 10 primers, since they have previously been useful to detect polymorphism among B. glabrata and/or B. tenagophila. The results showed polymorphisms with 5 primers. Polymorphic bands observed only in the susceptible strain. The RAPD-PCR methodology represents an adequate approach for the analysis of genetic polymorphisms. The understanding of the genetic polymorphisms associated to resistance may contribute to the future identification of genomic sequences related to the resistance/susceptibility of Biomphalaria to the larval forms of S. mansoni and to the development of new strategies for the control of schistosomiasis.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Pathology associated with vaccination against Schistosoma mansoni in mice using cryopreserved radiation attenuated schistosomula

    International Nuclear Information System (INIS)

    Twenty-one mice were injected intramuscularly with 2000 Schistosoma mansoni schistosomula irradiated at 20 krad and cryopreserved; three mice were killed on each of day 0, 2, 5, 9, 19, 28 and 44 days after infection and muscle from the site of injection in the left hind leg, the lungs and livers removed for histological examination. Schistosomula were seen in sections from the leg muscle from days 0 to 19 inclusive, in the lungs from day 2 to day 28 inclusive and in the livers from days 9 to 28 inclusive. Most schistosomula were seen in sections of the leg muscle with considerably fewer parasites occurring in the lungs and especially the livers. Granulomatous reactions comprising eosinophils, polymorphs, plasma cells and macrophages were first seen in the leg muscle on day 2, in the lungs on day 5 and in the liver on day 19. The peak inflammatory reactions appeared to occur between days 5 and 9, 9 and 19 and 28 and 44 respectively in the three tissues. The pathology is discussed in relation to the dose of irradiation required to attenuate the schistosomula for optimal immunogenicity. (author)

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Carcinogenesis associated with parasites other than Schistosoma, Opisthorchis and Clonorchis: A systematic review.

    Science.gov (United States)

    Machicado, Claudia; Marcos, Luis A

    2016-06-15

    Only three helminths (Schistosoma haematobium, Opisthorchis viverrini and Clonorchis sinensis) are directly associated with carcinogenesis in humans whereas the role of other parasites in cancer remains unclear. This study aimed to perform a systematic review to identify recent insights in the role of other parasite infections in carcinogenesis. We conducted systematic searches of MEDLINE and EMBASE on July 2015. Our primary outcome was the association between parasitic infections and carcinogenesis. Out of 1,266 studies, 19 were selected for detailed evaluation (eight for helminths and 11 for protozoa). The mechanisms of helminth-induced cancer included chronic inflammation, sustained proliferation, modulation of the host immune system, reprogramming of glucose metabolism and redox signaling, induction of genomic instability and destabilization of suppressor tumor proteins, stimulation of angiogenesis, resisting cell death, and activation of invasion and metastasis. In addition to the current knowledge, the following parasites were found in cancers or tumors: Echinococcus, Strongyloides, Fasciola, Heterakis, Platynosomum and Trichuris. Additional parasites were found in this systematic review that could potentially be associated with cancers or tumors but further evidence is needed to elaborate a cause-effect relationship. PMID:26840624

  16. 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

  17. 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.

  18. 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

  19. 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

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

    Science.gov (United States)

    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

  1. 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)

  2. 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.

  3. 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.

  4. [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

  5. 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.

  6. 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.

  7. Ultrasound monitoring of structural urinary tract disease in Schistosoma haematobium infection

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    King Charles H

    2002-01-01

    Full Text Available A major advance in our understanding of the natural history of Schistosoma haematobium-related morbidity has come through the introduction of the portable ultrasound machines for non-invasive examination of the kidneys and bladder. With the use of generators or battery packs to supply power in non-clinical field settings, and with the use of instant photography or miniaturized thermal printers to record permanent images, it is possible to examine scores of individuals in endemic communities every day. Broad-based ultrasound screening has allowed better definition of age-specific disease risks in urinary schistosomiasis. Results indicate that urinary tract abnormalities are common (18% overall prevalence in S. haematobium transmission areas, with a 2-4% risk of either severe bladder abnormality or advanced ureteral obstruction. In longitudinal surveys, ultrasound studies have shown that praziquantel and metrifonate therapy are rapidly effective in reversing urinary tract abnormalities among children. The benefits of treating adults are less well known, but research in progress should help to define this issue. Similarly, the prognosis of specific ultrasound findings needs to be clarified, and the ease of sonographic examination will make such long-term follow-up studies feasible. In summary, the painless, quick, and reproducible ultrasound examination has become an essential tool in the study of urinary schistosomiasis.

  8. Behavior of Schistosoma mansoni-induced histopathological lesions in Biomphalaria glabrata submitted to ionizing radiation

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    Azevedo Carine M.

    2004-01-01

    Full Text Available Present report demonstrates that repeated radiation of Schistosoma mansoni-infected Biomphalaria glabrata, totaling 15,000 rads, caused a sudden, albeit transient, suppression of cercarial shedding. Initially, sporocysts practically disappeared from the snail tissues. The more resistant developing cercariae presented nuclear clumping and vacuolation, before undergoing lysis. No host tissue reaction was evident at any time. Thirty-four days after the last irradiation, the snails resumed cercarial elimination. By that time numerous sporocysts and developing cercariae were detected, disseminated throughout snail tissues in a pattern similar to that of a highly malignant neoplasm, with no signs of host cellular reactions, which on the other hand were present in non-irradiated infected controls. The region of the ovo-testis was apparently destroyed after radiation, but returned to its normal appearance around 40 days after the last radiation. Ionizing radiation affected both host and parasite in S. mansoni-infected Biomphalaria glabrata, but the resulting impressive changes were soon reversed.

  9. Identification of Schistosoma mansoni glycoproteins recognized by protective antibodies from mice immunized with irradiated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, J.P.; Strand, M.; Mangold, B.L.; Dean, D.A.

    1986-01-01

    The humoral immune responses of mice patently infected with Schistosoma mansoni and of mice vaccinated with radiation-attenuated cercariae were compared by radioimmunoassays and one-and two-dimensional polyacrylamide gel analyses of radioimmunoprecipitates. Sera of vaccinated mice precipitated a restricted number of predominantly high m.w. glycoproteins of both schistosomula and adult worms metabolically labeled with (/sup 35/S) methinonine. Each of the glycoproteins of 36 hr in vitro-cultured schistosomula that was precipitated by the sera of vaccinated mice was also precipitated by sera of infected mice. In contrast, sera of vaccinated mice uniquely precipitated a 38,000 m.w. glycoprotein of schistosomula cultured for 5 days and a 94,000 m.w. glycoprotein of adult male worms. Although radiation-attenuated larvae do not reach the adult stage, mice vaccinated with these still elicit a strong immune response against egg glycoproteins. In particular, an egg glycoprotein of 85,000 to 70,000 and isoelectric point of 4.8 showed an enhanced reactivity with sera of vaccinated mice in comparison with infected mice. These results show that the antibody response in mice vaccinated with radiation-attenuated larvae differs qualitatively and quantitatively from that of infected mice.

  10. Identification of Schistosoma mansoni glycoproteins recognized by protective antibodies from mice immunized with irradiated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, J.P.; Strand, M.; Mangold, B.L.; Dean, D.A.

    1986-06-15

    The humoral immune response of mice patently infected with Schistosoma mansoni and of mice vaccinated with radiation-attenuated cercariae were compared by radioimmunoassays and one-and two-dimensional polyacrylamide gel analyses of radioimmunoprecipitates. The binding observed with antibodies of mice vaccinated twice with radiation-attenuated cercariae over a period of 7 to 11 wk was less than 50% of the binding observed with antibodies of mice patently infected for 20 wk, but three to four times greater than that obtained with antibodies of mice infected for 6 wk, irrespective of whether the test extracts were derived from schistosomula or adult worms. Sera of vaccinated mice precipitated a restricted number of predominantly high m.w. glycoproteins of both schistosomula and adult worms metabolically labeled with sulfur-35 methionine. Each of the glycoproteins of 36 hr in vitro-cultured schistosomula that was precipitated by the sera of vaccinated mice was also precipitated by the sera of infected mice. Although radiation-attenuated larvae do not reach the adult stage, mice vaccinated with these still elicit a strong immune response against egg glycoproteins. These results show that the antibody response in mice vaccinated with radiation-attenuated larvae differs qualitatively and quantitatively from that of infected mice.

  11. Schistosoma mansoni: the prophylactic and curative effect of propolis in experimentally mice

    International Nuclear Information System (INIS)

    To evaluate the effect of propolis, a natural bee product on lung and liver schistosomules as well on adult worms of Schistosoma mansoni in immunosuppressed mice. All groups were infected with 100+-10 S. mansoni cercariae/mouse injected subcutaneously. Immunosuppression was induced by hydrocortisone hemisuccinate at a dose of 25 mg/kg b.w. intramusculary twice weekly for 8 weeks, starting 10 days before infection. Propolis was administered orally at a dose of 250 mg/kg/day, starting 5 days before infection and continued up to 45 days postinfection, to cover all stages of S. mansoni infection. Praziquantel (PZQ) was administered orally at a dose of 500 mg/kg/day, on the 5th and 6th and 45th and 46th days post-infection. The number of lung schistosomules showed a significant reduction of 59.22% with propolis and 98.89% with PZQ. The administration of propolis caused a marked reduction of egg counts in stool (61.8%) and tissues (49.9% and 45.8%). Propolis produced a significant reduction of 58.38% in adult worms. PZQ produced a reduction of 83.65% in adult worms and 98.38% in stool egg counts and (91.99% and 89.22% ) reductions in liver and intestine egg counts respectively. The effect of propolis when compared to PZQ is promising in immunosuppressed S. mansoni infected mice. (author)

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

    International Nuclear Information System (INIS)

    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 [35S]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 125I-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

  13. Regional and splenic lymphocyte proliferative responses of mice exposed to normal or irradiated Schistosoma mansoni cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, F.A.; Wilson, E.M.

    1982-05-01

    Developing larvae of Schistosoma mansoni migrate through various tissues en route to the liver and mesenteric veins of their definitive host. Regional (lymph node) and systemic (spleen) blastogenic responses to cercarial, adult and egg antigens were measured in CBA/J mice at various times after exposure to normal or irradiated S. mansoni cercariae. Among the separate lymph node groups studied were those draining the tail, thoracic region, intestines, head and neck, and the pelvis. Blastogenic responses were assayed by a micromethod requiring 10(5) cells in 20 microliter volumes per culture. Up to 5 weeks post-cercarial exposure the pattern of responses in lymphoid tissues of infected mice coincided with the migratory route of the parasites. Following oviposition, cellular reactivity was pronounced in all lymph node groups. The reactivity of mice exposed to irradiated cercariae followed a pattern suggestive of a sustained antigenic stimulus only in the nodes draining the tail and lungs. Splenic (systemic) reactivity was roughly comparable between the two exposure groups. These data show the independence and vast differences in the host regional responses following normal or irradiated cercarial exposure.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. 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.

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

    International Nuclear Information System (INIS)

    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. (author)

  17. Schistosoma mansoni: quantification of skin penetration and early migration by differential external radioassay and autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Georgi, J.R. (New York State College of Veterinary Medicine, Ithaca (USA))

    1982-04-01

    Eleven gamma-emitting radionuclides (/sup 49/Sc, /sup 54/Mn, /sup 59/Fe, /sup 60/Co, /sup 65/Zn, /sup 75/Se (as selenomethionine, selenocystine, selenite and selenate), /sup 109/Cd, /sup 125/Sb, /sup 133/Ba, /sup 137/Cs and /sup 203/Hg) were screened as labelling agents for Schistosoma mansoni cercariae by incubation of infected Biomphalaria glabrata snails in radioactive solution. Only (/sup 75/Se)methionine yielded satisfactorily labelled cercariae. Differential external radioassay, a new technique employing partial body shielding within a total body counter, permitted separate estimation of tail and body radioactivity of conscious mice previously exposed by tail immersion to /sup 75/Se-labelled cercariae, with measurements repeated as often as desired. Approximately 39% of the /sup 75/Se present in emergent cercariae was retained by schistosomula transformed in vitro but this was subject to considerable variation, especially in schistosomula transformed in vivo. Secreted or catabolized label from penetrant cercariae and schistosomula was rapidly removed from the skin by the bloodstream. Numbers of schistosomula in tail skin were directly proportional to the number of reduced silver foci counted on tail autoradiograms; only a very small fraction of tail radioactivity represented unbound ('spurious') label. Migration of schistosomula away from skin was 50% complete at 3.8-4.3 days, as determined by probit analysis of autoradiographic data.

  18. Immunization of rats against Schistosoma mansoni using irradiated cercariae, lung schistosomula and liver-stage worms

    Energy Technology Data Exchange (ETDEWEB)

    Ford, M.J.; Bickle, Q.D.; Taylor, M.G. (London School of Hygiene and Tropical Medicine, St. Albans (UK). Winches Farm Field Station)

    1984-10-01

    In PVG rats a single immunizing infection with Schistosoma mansoni cercariae exposed to 0 - 20 krad. gamma radiation failed to induce more than minimal resistance to challenge 4 weeks later, whereas 4 immunizations with 20 krad.-irradiated cercariae, over several months, induced substantial resistance. In contrast, significant protection was induced in Fischer rats by a single immunization with unirradiated cercariae or cercariae irradiated with up to 80 krad. Comparable resistance was induced by 2 - 20 krad.-irradiated cercariae and lower levels by 10 - 80 krad.-irradiated infections. Although the resistance induced by a single dose of 1000 20 krad.-irradiated cercariae could be boosted by a second, further immunizations failed to enhance this resistance. Comparison of the migration and survival of unirradiated and of 20 and 40 krad.-irradiated cercariae revealed dramatic differences in their fate: parasites exposed to 40 krad. remained in the skin, while the majority of 20 krad.-irradiated parasites died in the lungs after a sojourn of at least 14 days. The immunizing potential of older parasites was investigated by exposing rats to lung and liver-stage larvae injected into the tail and mesenteric veins, respectively.

  19. Identification of Schistosoma mansoni glycoproteins recognized by protective antibodies from mice immunized with irradiated cercariae

    International Nuclear Information System (INIS)

    The humoral immune responses of mice patently infected with Schistosoma mansoni and of mice vaccinated with radiation-attenuated cercariae were compared by radioimmunoassays and one-and two-dimensional polyacrylamide gel analyses of radioimmunoprecipitates. Sera of vaccinated mice precipitated a restricted number of predominantly high m.w. glycoproteins of both schistosomula and adult worms metabolically labeled with [35S] methinonine. Each of the glycoproteins of 36 hr in vitro-cultured schistosomula that was precipitated by the sera of vaccinated mice was also precipitated by sera of infected mice. In contrast, sera of vaccinated mice uniquely precipitated a 38,000 m.w. glycoprotein of schistosomula cultured for 5 days and a 94,000 m.w. glycoprotein of adult male worms. Although radiation-attenuated larvae do not reach the adult stage, mice vaccinated with these still elicit a strong immune response against egg glycoproteins. In particular, an egg glycoprotein of 85,000 to 70,000 and isoelectric point of 4.8 showed an enhanced reactivity with sera of vaccinated mice in comparison with infected mice. These results show that the antibody response in mice vaccinated with radiation-attenuated larvae differs qualitatively and quantitatively from that of infected mice

  20. Immunization of mice with gamma-irradiated intramuscularly injected schistosomula of Schistosoma mansoni

    International Nuclear Information System (INIS)

    The parameters involved in the induction of resistance against Schistosoma mansoni by injection of irradiated, artificially transformed schistosomula were studied in mice. Single intramuscular injections of 500 schistosomula exposed to radiation doses in the range 2.3 to 160 krad. resulted in significant protection ( in the range 20 to 50% as assessed by reduced worm burdens) against a challenge infection administered at intervals from 3 to 24 weeks post-vaccination. However, schistosomular irradiated with 20 krad. consistently resulted in better protection than those exposed to either higher or lower radiation doses despite the persistence of stunted adults from the infections irradiated with 2.3 krad. Vaccination with 40 krad. schistosomula resulted in significant protection in terms of reduced worm and tissue egg burdens and increased survival following lethal challenge. Varying the number of irradiated schistosomula, the frequency and route of their administration, the site of challenge and the strain of host all failed to enhance the level of resistance. However, percutaneously applied, irradiated cercariae were found to be more effective in stimulating resistance (60%) than intramuscularly injected, irradiated schistosomula (40%). (author)