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Sample records for biomphalaria glabrata snails

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

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    Coen M Adema

    2006-10-01

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

  2. Influence of experimental illumination and seasonal variation on crossbreending mating in the snail Biomphalaria Glabrata

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    F. Pimentel-Souza; V. T. Schall; N. D. C. Barbosa; Schettino, M.; R. Lautner Júnior.

    1988-01-01

    The crossbreeding activities of the Schistosoma mansoni vector snail Biomphalaria glabrata were counted in a laboratory aquarium throughout the year under two regimes of 12h light: 12h dark from 7 A., M. to 10 P. M. Mating increased significantly in Authmn and Winter and just missed a significant inverse correlation with temperature and a direct one with locomotion. Other similar experiments were carried out to compare mating under various ilumination conditions in complete daily cycle measur...

  3. Ecology of bacterial communities in the schistosomiasis vector snailBiomphalaria glabrata.

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    Ducklow, H W; Clausen, K; Mitchell, R

    1981-09-01

    The internal colony-forming bacterial flora of the schistosome intermediate host snailBiomphalaria glabrata (Say) has been characterized in ca. 500 individual snails from Puerto Rico, Guadeloupe, and St. Lucia, and from laboratory aquaria. Freshly captured wild snails harbor 2-40×10(6) CFU·g(-1), and healthy aquarium snails harbor 4-16×10(7) CFU·g(-1), whereas moribund individuals have 4-10 times as many bacteria as healthy individuals from the same habitats.Pseudomonas spp. are the most common predominant bacteria in normal snails, whereasAcinetobacter, Aeromonas, andMoraxella spp. predominate in moribund snails. External bacterial populations in water appear to have little effect on the composition and size of the flora in any snail. In addition to normal (healthy) and moribund snails, a third group of snails has been distinguished on the basis of internal bacterial density and predominating genera. These "high-density" snails may have undergone stresses and may harbor opportunistic pathogens. The microfloras of wild and laboratory-reared snails can be altered and stimulated to increase in density by crowding the snails or treating them with antibiotics. PMID:24227500

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

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

    2001-05-15

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

  5. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni.

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

    2014-09-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bacteria, for example, can induce beneficial chromatin remodelling of the host genome. We have previously shown in vitro that Biomphalaria glabrata embryonic cells co-cultured with schistosome miracidia display genes changing their nuclear location and becoming up-regulated. This also happens in vivo in live intact snails, where early exposure to miracidia also elicits non-random repositioning of genes. We reveal differences in the nuclear repositioning between the response of parasite susceptible snails as compared to resistant snails and with normal or live, attenuated parasites. Interestingly, the stress response gene heat shock protein (Hsp) 70 is only repositioned and then up-regulated in susceptible snails with the normal parasite. This movement and change in gene expression seems to be controlled by the parasite. Other differences in the behaviour of genes support the view that some genes are responding to tissue damage, for example the ferritin genes move and are up-regulated whether the snails are either susceptible or resistant and upon exposure to either normal or attenuated parasite. This is the first time host genome reorganisation has been seen in a parasitic host and only the second time for any pathogen. We believe that the parasite elicits a spatio-epigenetic reorganisation of the host genome to induce favourable gene expression for itself and this might represent a fundamental mechanism present in the human host infected with schistosome cercariae as well as in

  6. The Structure of the Statocyst of the Freshwater Snail Biomphalaria Glabrata (Pulmonata, Basommatophora)

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    Gao, Wenyuan; Wiederhold, Michael L.

    1997-01-01

    The structure of the statocyst of the freshwater snail Biomphalaria glabrata has been examined by light and electron microscopy. The two statocysts are located on the dorsal-lateral side of the left and right pedal ganglion. The statocysts are spherical, fluid-filled capsules with a diameter of approximately 60 microns for young and 110 microns for adult snails. The wall of the cyst is composed of large receptor cells and many smaller supporting cells. The receptor cells bear cilia which are evenly distributed on the apical surface. The cilia have the typical 9+2 internal tubule configuration. Striate rootlets originate from the base of the basal body and run downward into the cytoplasm. Side-roots arise from one side of the basal body and a basal foot from the other. For each receptor cell, the basal foot always points to the periphery of the surface, indicating that the receptor cell is non-polarized. The receptor cells contain cytoplasmic organelles such as mitochondria, ribosomes, rough and smooth endoplasmic reticulum, compact Golgi bodies and multivesicular bodies. Supporting cells bearing microvilli are interposed between the receptor cells. The junction complex between the supporting cells and the receptor cells is composed of adherens and septate junctions, while between supporting cells only the adherens junctions are present. The static nerve arises from the lateral side of the cyst and contains axons in which parallel neurotubules and mitochondria are found. The axons arise directly from the base of the receptor cells without synapse. In the cyst lumen there are unattached statoconia. The statoconia have a plate-like or concentric membranous ring structure. Based on the morphology, the function of the statocyst in Biomphalaria is discussed.

  7. Influence of experimental illumination and seasonal variation on crossbreending mating in the snail Biomphalaria Glabrata

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    F. Pimentel-Souza

    1988-03-01

    Full Text Available The crossbreeding activities of the Schistosoma mansoni vector snail Biomphalaria glabrata were counted in a laboratory aquarium throughout the year under two regimes of 12h light: 12h dark from 7 A., M. to 10 P. M. Mating increased significantly in Authmn and Winter and just missed a significant inverse correlation with temperature and a direct one with locomotion. Other similar experiments were carried out to compare mating under various ilumination conditions in complete daily cycle measurements. Mating counts decreased under the regimes which submited snail to a total exposure of 12h light and 12 dark during a daily cycle in the following sequence: 12h light: 12h dark alternating hourly with light gradient, 12h light: 12h dark, 1h light: 1h dark and 12h dark: 12h light. Under two constant illuminations, the mating scored less than under the previous conditions, except under 12h light. Under darkeness the mating count was lower than light conditions. There was no way to differentiate the night and day rhythms of mating on different days in each regime, except for mating under 12h light: 12 dark alternating with light gradient, constant dark and 12h dark: 12h light conditions. Mating increased in certain light and temperature conditions, in wich the intensities, should have an optimum value.

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

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    Di Liang

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

  9. Estudo sobre a cópula interespecífica entre moluscos planorbídeos Biomphalaria glabrata e B. tenagophila Inter-specific mating between planorbid snails Biomphalaria glabrata and B. tenagophila

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    Luiz A. Magalhães

    1973-09-01

    Full Text Available Foi estudada a freqüência da cópula interespecífica entre espécimes de Biomphalaria glabrata e B. tenagophila. Os resultados da experiência levaram a conclusão de que há preferência pela cópula intraespecífica, ocorrendo, contudo, cópulas interespecíficas.An experiment on the inter-specific mating of B. glabrata and B. tenagophila snails was related. The results led to conclude that the snails prefer intra-specific mates, even though inter-specific ones occur.

  10. Developmental toxicity, acute toxicity and mutagenicity testing in freshwater snails Biomphalaria glabrata (Mollusca: Gastropoda) exposed to chromium and water samples.

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    Tallarico, Lenita de Freitas; Borrely, Sueli Ivone; Hamada, Natália; Grazeffe, Vanessa Siqueira; Ohlweiler, Fernanda Pires; Okazaki, Kayo; Granatelli, Amanda Tosatte; Pereira, Ivana Wuo; Pereira, Carlos Alberto de Bragança; Nakano, Eliana

    2014-12-01

    A protocol combining acute toxicity, developmental toxicity and mutagenicity analysis in freshwater snail Biomphalaria glabrata for application in ecotoxicological studies is described. For acute toxicity testing, LC50 and EC50 values were determined; dominant lethal mutations induction was the endpoint for mutagenicity analysis. Reference toxicant potassium dichromate (K2Cr2O7) was used to characterize B. glabrata sensitivity for toxicity and cyclophosphamide to mutagenicity testing purposes. Compared to other relevant freshwater species, B. glabrata showed high sensitivity: the lowest EC50 value was obtained with embryos at veliger stage (5.76mg/L). To assess the model applicability for environmental studies, influent and effluent water samples from a wastewater treatment plant were evaluated. Gastropod sensitivity was assessed in comparison to the standardized bioassay with Daphnia similis exposed to the same water samples. Sampling sites identified as toxic to daphnids were also detected by snails, showing a qualitatively similar sensitivity suggesting that B. glabrata is a suitable test species for freshwater monitoring. Holding procedures and protocols implemented for toxicity and developmental bioassays showed to be in compliance with international standards for intra-laboratory precision. Thereby, we are proposing this system for application in ecotoxicological studies. PMID:25259848

  11. Molluscicidal activity of Moringa oleiferaon Biomphalaria glabrata: integrated dynamics to the control of the snail host of Schistosoma mansoni

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    Cesar Luiz Pinto Ayres Coelho da Silva

    2013-10-01

    Full Text Available The ground seed of Moringa oleifera Lam., Moringaceae, has been evaluated for its molluscicidal activity against the snails Biomphalaria glabrata, Physa marmorata and Melanoides tuberculatus. The results show that M. oleifera is active against B. glabrata (LC50 0.419 g/l; LC90 1.021 g/l and P. marmorata (LC50 0.339 g/l; LC90 0.789 g/l but has no effect against M. tuberculatus. The great innovation of the use of M. oleifera, in addition to being innocuous to humans, is the present nutritional potential for humans and animals as well as providing an ecosystemic service as water purifier.

  12. The molluscicidal activity of the latex of Euphorbia splendens var. hislopii on Melanoides tuberculata (Thiaridae), a snail associated with habitats of Biomphalaria glabrata (Planorbidae)

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    Alexandre Giovanelli; Cesar Luiz Pinto Ayres Coelho da Silva; Luisa Medeiros; Maurício Carvalho Vasconcellos

    2001-01-01

    The use of the latex of Euphorbia splendens var. hislopii was considered as an effective control method for Biomphalaria glabrata in Sumidouro, Rio de Janeiro. However, the appearance and expansion of the snail Melanoides tuberculata since August 1997, with the concomitant reduction of the population of B. glabrata suggest that competitive exclusion might be taking place. Depending on the susceptibility of the thiarid to the E. splendens toxin, the natural control that is occurring could be i...

  13. Study of the snail intermediate hosts for Schistosoma mansoni on Itamaracá Island in northeast Brazil: spatial displacement of Biomphalaria glabrata by Biomphalaria straminea.

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    Barbosa, Constança S; Barbosa, Verônica S; Nascimento, Wheverton C; Pieri, Otavio S; Araújo, Karina C G M

    2014-05-01

    In 2012 a malacological survey of the breeding sites of Biomphalaria glabrata and B. straminea , the two intermediate host snails of Schistosoma mansoni , was carried out on Itamaraca Island in Pernambuco, Brazil. This study has now been extended by studying the competition between the two species. Snails were collected and dissected to identify the species and tests were performed to verify S. mansoni infection. Student's t test was used to compare the proportion between the two species and their breeding sites and a parasitological survey was conducted among local residents, using the Kato-Katz method. The spatial distribution of the two snail species was determined using TerraView, while a snail density map was constructed by Kernel estimate. The survey identified two breeding sites for B. glabrata with 17 specimens and 19 breeding sites for B. straminea with 459 snails, all of them negative for S. mansoni infection. The statistical analysis revealed that the proportion of the numbers of specimens and breeding sites of B. straminea (37.84 ± 9.01) were significantly greater than those of B. glabrata (8.50 ± 6.50). Parasitological examinations from 41 residents diagnosed two cases of schistosomiasis with parasite loads of 60 and 84 eggs per 1 g of stool, respectively. This indiction of a competitive process between the two snail species requires monitoring of schistosomiasis in the resident and travelling human populations occupying this environment, which could potentially result in social and economic changes on the island risking its attraction as a centre for eco-tourism. PMID:24893012

  14. Genetic markers between Biomphalaria glabrata snails susceptible and resistant to Schistosoma mansoni infection

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    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.

  15. Competitive interactions between species of freshwater snails. I. Laboratory studies: Ib. Comparative studies of the dispersal and the vagility capabilities of Biomphalaria glabrata and Biomphalaria straminea

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    Barbosa, Frederico S.; D. P. Pereira da Costa; F. Arruda

    1984-01-01

    Experiments reported in the current paper, carried out under semi-field conditions created in the laboratory, have shown that b. straminea has competitive superiority when compared with B. glabrata. The former species has shown higher capabilities of both dispersal and vagility. In addition, B. straminea was able to compete sucessfully with B. glabrata.Resultados do presente trabalho indicam a superioridade competitiva de Biomphalaria straminea sobre Biomphalaria glabrata. A primeira destas e...

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

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

    2016-06-01

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

  17. Padronização da técnica de marcação de caramujos Biomphalaria glabrata com radioestroncio Standardization of the technic of labeling Biomphalaria glabrata snails with radiostrontium

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    Miguel Archanjo Muniz Leal

    1982-06-01

    Full Text Available Caramujos Biomphalaria glabrata vetor da esquistossomose mansônica, utilizados em experiências de campo, nas quais se faz necessário sua identificação e/ou localização, devem ser marcados com radioestrôncio 85,89 ou 90. Sua marcação em laboratório deve ser procedida em aquários de vidro sem fundo de areia, temperatura de 26,5 ± 1ºC, pH ajustado ao valor encontrado no "habitat", aeração artificial, alimentação diária com pequenas porções de alface fresca e 25 ml de água desionizada por caramujo. O nível de atividade no caramujo pode ser estimado sabendo-se que para o tempo de marcação de 5 dias e atividades iniciais de 0,036 a 0,362 µCi/ml, a captação global para grupos de 10 caramujos está em torno de 84 ± 2% e que a marcação em água contendo cálcio, praticamente não se altera até concentrações de 50ppm. A sobrevida ao longo de nove semanas não foi influenciada pela presença de radioestrôncio no caramujo.The vector snail of schistosomiasis mansoni, Biomphalaria glabrata, when used in field experiments in which it is to be recovered and/or located, should be labeled with radiostrontium 85,89 or 90. The labeling in laboratory should be carried out in an artificially aerated aquarium with 25 ml of deionized water per snail, without sand at the bottom, at a temperature of 26.5 ± 1ºC, pH adjusted to the value found in the natural habitat, and the snails should be fed with small pieces of fresh lettuce. The level of snail activity can be estimated taking into account that, for a labeling time of 5 days and initial activities of 0.036 to 0.362 µCi/ml, the global uptake for groups of 10 snails is about 84 ± 2% and that labeling in calcium-containing water parctically does not change till a 50 ppm concentration. Survival along 9 weeks was not influenced by the presence of radiostrontium in the snail.

  18. The molluscicidal activity of the latex of Euphorbia splendens var. hislopii on Melanoides tuberculata (Thiaridae, a snail associated with habitats of Biomphalaria glabrata (Planorbidae

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    Giovanelli Alexandre

    2001-01-01

    Full Text Available The use of the latex of Euphorbia splendens var. hislopii was considered as an effective control method for Biomphalaria glabrata in Sumidouro, Rio de Janeiro. However, the appearance and expansion of the snail Melanoides tuberculata since August 1997, with the concomitant reduction of the population of B. glabrata suggest that competitive exclusion might be taking place. Depending on the susceptibility of the thiarid to the E. splendens toxin, the natural control that is occurring could be interrupted by the employment of the latex if the planorbid were less susceptible to the toxin. The aim of this study is to investigate the molluscicidal activity of the latex on M. tuberculata. We used 420 M. tuberculata, from Sumidouro. Fourteen different latex concentrations were tested using World Health Organization general methodology. Probit analysis was used for LD90 and LD50 determination. The LD50 was 3.57 mg/l and LD90 was 6.22 mg/l. At the highest concentration (10 mg/l there was no survival. No significant differences among replicas (chi2 = 8.31; gl = 13; p > 0.05 were found. The LD90 dose for M. tuberculata was 13.8 times greater than that for B. glabrata, so that the molluscicide in the presence of the thiarid may have a synergic effect on reduction of Biomphalaria populations.

  19. Biomphalaria glabrata transcriptome: cDNA microarray profiling identifies resistant- and susceptible-specific gene expression in haemocytes from snail strains exposed to Schistosoma mansoni

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    Rollinson David

    2008-12-01

    Full Text Available Abstract Background Biomphalaria glabrata is an intermediate snail host for Schistosoma mansoni, one of the important schistosomes infecting man. B. glabrata/S. mansoni provides a useful model system for investigating the intimate interactions between host and parasite. Examining differential gene expression between S. mansoni-exposed schistosome-resistant and susceptible snail lines will identify genes and pathways that may be involved in snail defences. Results We have developed a 2053 element cDNA microarray for B. glabrata containing clones from ORESTES (Open Reading frame ESTs libraries, suppression subtractive hybridization (SSH libraries and clones identified in previous expression studies. Snail haemocyte RNA, extracted from parasite-challenged resistant and susceptible snails, 2 to 24 h post-exposure to S. mansoni, was hybridized to the custom made cDNA microarray and 98 differentially expressed genes or gene clusters were identified, 94 resistant-associated and 4 susceptible-associated. Quantitative PCR analysis verified the cDNA microarray results for representative transcripts. Differentially expressed genes were annotated and clustered using gene ontology (GO terminology and Kyoto Encyclopaedia of Genes and Genomes (KEGG pathway analysis. 61% of the identified differentially expressed genes have no known function including the 4 susceptible strain-specific transcripts. Resistant strain-specific expression of genes implicated in innate immunity of invertebrates was identified, including hydrolytic enzymes such as cathepsin L, a cysteine proteinase involved in lysis of phagocytosed particles; metabolic enzymes such as ornithine decarboxylase, the rate-limiting enzyme in the production of polyamines, important in inflammation and infection processes, as well as scavenging damaging free radicals produced during production of reactive oxygen species; stress response genes such as HSP70; proteins involved in signalling, such as importin 7

  20. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide.

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    Zhang, Si-Ming; Buddenborg, Sarah K; Adema, Coen M; Sullivan, John T; Loker, Eric S

    2015-01-01

    In view of the call by the World Health Organization (WHO) for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy-based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biology and may offer valuable insights into the development of better chemical control methods for snails. We used a recently developed Biomphalaria glabrata oligonucleotide microarray (31K features) to investigate the effect of sublethal exposure to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. Most of the genes highly upregulated following exposure of snails to niclosamide are involved in biotransformation of xenobiotics, including genes encoding cytochrome P450s (CYP), glutathione S-transferases (GST), and drug transporters, notably multi-drug resistance protein (efflux transporter) and solute linked carrier (influx transporter). Niclosamide also induced stress responses. Specifically, six heat shock protein (HSP) genes from three super-families (HSP20, HSP40 and HSP70) were upregulated. Genes encoding ADP-ribosylation factor (ARF), cAMP response element-binding protein (CREB) and coatomer, all of which are involved in vesicle trafficking in the Golgi of mammalian cells, were also upregulated. Lastly, a hemoglobin gene was downregulated, suggesting niclosamide may affect oxygen transport. Our results show that snails mount substantial responses to sublethal concentrations of niclosamide, at least some of which appear to be protective. The topic of how niclosamide's lethality at higher concentrations is determined requires further study. Given that niclosamide has also been used as an anthelmintic drug for decades and has been

  1. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide.

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    Si-Ming Zhang

    Full Text Available In view of the call by the World Health Organization (WHO for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy-based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biology and may offer valuable insights into the development of better chemical control methods for snails. We used a recently developed Biomphalaria glabrata oligonucleotide microarray (31K features to investigate the effect of sublethal exposure to niclosamide on the transcriptional responses of the snail B. glabrata relative to untreated snails. Most of the genes highly upregulated following exposure of snails to niclosamide are involved in biotransformation of xenobiotics, including genes encoding cytochrome P450s (CYP, glutathione S-transferases (GST, and drug transporters, notably multi-drug resistance protein (efflux transporter and solute linked carrier (influx transporter. Niclosamide also induced stress responses. Specifically, six heat shock protein (HSP genes from three super-families (HSP20, HSP40 and HSP70 were upregulated. Genes encoding ADP-ribosylation factor (ARF, cAMP response element-binding protein (CREB and coatomer, all of which are involved in vesicle trafficking in the Golgi of mammalian cells, were also upregulated. Lastly, a hemoglobin gene was downregulated, suggesting niclosamide may affect oxygen transport. Our results show that snails mount substantial responses to sublethal concentrations of niclosamide, at least some of which appear to be protective. The topic of how niclosamide's lethality at higher concentrations is determined requires further study. Given that niclosamide has also been used as an anthelmintic drug for decades and

  2. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni

    OpenAIRE

    Arican-Goktas, HD; Ittiprasert, W; Bridger, JM; Knight, M.

    2014-01-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bact...

  3. Differential spatial repositioning of activated genes in Biomphalaria glabrata snails infected with Schistosoma mansoni.

    OpenAIRE

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

    2014-01-01

    Schistosomiasis is an infectious disease infecting mammals as the definitive host and fresh water snails as the intermediate host. Understanding the molecular and biochemical relationship between the causative schistosome parasite and its hosts will be key to understanding and ultimately treating and/or eradicating the disease. There is increasing evidence that pathogens that have co-evolved with their hosts can manipulate their hosts' behaviour at various levels to augment an infection. Bact...

  4. Biomphalaria glabrata no Estado do Piauí Biomphalaria glabrata in the State of Piaui

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1984-09-01

    Full Text Available É registrado o primeiro encontro do molusco planorbideo Biomphalaria glabrata, hospedeiro intermediário do Schistosoma mansoni, no Estado do Piauí, coletado em vários criadouros na cidade de Parnaíba. O exame de 694 exemplares revelou a presença de formas evolutivas de algumas espécies de trematodeos, mas não de Schistosomatidea. Nenhum caso autoctone de xistosomose foi até agora identificado na população humana da cidade. A presença da B. glabrata em Parnaíba amplia em 20 km para leste a área de sua distribuição na Região Litoral Norte da Grande Região Nordeste do Brasil onde era conhecida até em Avaioses no extremo leste da parte maranhense da referida Região. Outros moluscos também coletados nos mesmos criadouros foram Biomphalaria straminea, Drepanotrema lucidum. D. cimex, D. depressissimum, Physidae e Ampullarriidae.The occurrence of Biomphalaria glabrata is recorded for the first time in the state of Piauí, where it was collected from several breeding places in the city of Parnaíba. Examination of 694 specimens showed that a part of them were infected with trematodes other than Schistosomatidae. So far no autochthonous cases of schistosomiasis have been identified in the city. The presence of B. glabrata in Parnaíba extends by 20 Km eastward its range on the Northern Coastal region of the Great Northeastern region of Brazil, where it had been found as far as Araioses, on the eastern extreme of the state of Maranhão. Other snail species collected from the same breeding places were Biomphalaria straminea, Drepanotrema lucidum, D. cimex, D. depressissimum, Physidae and Ampullariidae.

  5. Isolation and characterization of the full-length cDNA encoding a member of a novel cytochrome p450 family (CYP320A1) from the tropical freshwater snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni

    OpenAIRE

    Lockyer, Anne E.; Noble, Leslie R.; David Rollinson; Jones, Catherine S.

    2005-01-01

    Cytochrome p450s (cyp450s) are a family of structurally related proteins, with diverse functions, including steroid synthesis and breakdown of toxins. This paper reports the full-length sequence of a novel cyp450 gene, the first to be isolated from the tropical freshwater snail Biomphalaria glabrata, an important intermediate host of Schistosoma mansoni. The nucleotide sequence is 2291 bp with a predicted amino acid sequence of 584aa. The sequence demonstrates conserved cyp450 structural moti...

  6. Contribution to the histology of Biomphalaria glabrata Contribuição à histologia da Biomphalaria glabrata

    OpenAIRE

    Queli Teixeira Lemos

    1999-01-01

    A combination of histological techniques applied to the study of Biomphalaria glabrata yielded some interesting new data about the histology of this snail, a major intermediate host of Schistosoma mansoni in Brazil. Three kinds of pigments were identified: a dark pigment which bleached following oxidation with potassium permanganate; a lipofuchsin-like, diastase-resistant PAS-positive pigment and an iron-containing pigment, probably related to hemosiderin. Calcium was detected in small deposi...

  7. The molluscicidal activity of niclosamide (Bayluscide WP70®) on Melanoides tuberculata (Thiaridae), a snail associated with habitats of Biomphalaria glabrata (Planorbidae)

    OpenAIRE

    2002-01-01

    The aim of this study was to determine the toxicity of niclosamide (Bayluscide ®) on Melanoides tuberculata and Biomphalaria glabrata under laboratory conditions. The latter species is the intermediate host of Schistosoma mansoni (Sambon 1917). M. tuberculata was successfully used as competitor of B. glabrata in biological control programs in French West Indies. Both molluscicide and biological control using M. tuberculata have proved to be successful in reducing the population density of B. ...

  8. Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

    International Nuclear Information System (INIS)

    Ultrastructural studies of Biomphalaria glabrata embryos (MOllusca: Gastropoda), and important snail vector of schistosomiasis has not been explored. In the present work it was evaluated a suitable electron microscopical technique for embryos processing. Promising results was obtained with double fixation in 1% glutaraldehyde plus 1% osmium tetroxide in 0.05 M cacodylate buffer (pH 7.4), preliminary staining overnight in 1% uranyl acetate and embedding in EPON or Polylite under vacuum. It was used embryos at young trochophore stage wich is characterized by active organogenesis. Some ultrastructural aspects of B. glabrata embryos cells are presented. (author)

  9. Development of Schistosoma mansoni in Biomphalaria tenagophila, Biomphalaria straminea and Biomphalaria glabrata Desenvolvimento do Schistosoma mansoni em Biomphalaria tenagophila, Biomphalaria straminea e Biomphalaria glabrata

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    Cecilia Pereira de Souza

    1995-06-01

    Full Text Available A comparative study of the development of Schistosoma mansoni during the intra-molluscan phase was made by means of histological sections of Biomphalaria tenagophila, B. straminea and B. glabrata from Brazil. Two hundred snails of each species were individually exposed to 50 miracidia of the S. mansoni, AL line. No larvae were observed in the snails fixed 72 h after exposure. In specimens shedding cercariae, 31 days after exposure tissue reactions encapsulating the larvae were seen in B. tenagophila and B. straminea, in the head-foot, mantle collar and renal ducts. No tissue reactions occurred in the digestive glands of these two species. In B. glabrata the presence of numerous sporocysts and cercariae without tissue reactions was observed in the digestive gland, and other organs. The levels of infection of the snails and the average numbers of cercariae shed per day were 32.6% and 79±90 respectively for B. tenagophila, 11.3% and 112±100 for B. straminea and 75.3% and 432±436 for B. glabrata. The lower levels of infection and average numbers of cercariae shed by B. tenagophila and B. straminea are thus related to their more potent internal defense systems.Foi feito estudo comparativo do desenvolvimento do Schistosoma mansoni na fase intra-molusco, através de cortes histológicos, em Biomphalaria tenagophila, B. straminea e B. glabrata. Duzentos moluscos de cada espécie foram expostos individualmente a 50 miracídios de S. mansoni da linhagem AL. Nenhuma larva foi observada nos exemplares fixados 72 horas após a exposição. Nos exemplares eliminando cercárías, 31 dias após a exposição, foram observadas reações teciduais de encapsulamento de larvas em B. tenagophila e B. straminea, na região cefalopodal, colar do manto e dutos renais. Nas glândulas digestivas das duas espécies não foram observadas reações. Em B. glabrata foi registrada a presença de numerosos esporocistos e cercárias sem reação tecidual na gl

  10. Pathogen-associated molecular patterns activate expression of genes involved in cell proliferation, immunity and detoxification in the amebocyte-producing organ of the snail Biomphalaria glabrata.

    Science.gov (United States)

    Zhang, Si-Ming; Loker, Eric S; Sullivan, John T

    2016-03-01

    The anterior pericardial wall of the snail Biomphalaria glabrata has been identified as a site of hemocyte production, hence has been named the amebocyte-producing organ (APO). A number of studies have shown that exogenous abiotic and biotic substances, including pathogen associated molecular patterns (PAMPs), are able to stimulate APO mitotic activity and/or enlarge its size, implying a role for the APO in innate immunity. The molecular mechanisms underlying such responses have not yet been explored, in part due to the difficulty in obtaining sufficient APO tissue for gene expression studies. By using a modified RNA extraction technique and microarray technology, we investigated transcriptomic responses of APOs dissected from snails at 24 h post-injection with two bacterial PAMPs, lipopolysaccharide (LPS) and peptidoglycan (PGN), or with fucoidan (FCN), which may mimic fucosyl-rich glycan PAMPs on sporocysts of Schistosoma mansoni. Based upon the number of genes differentially expressed, LPS exhibited the strongest activity, relative to saline-injected controls. A concurrent activation of genes involved in cell proliferation, immune response and detoxification metabolism was observed. A gene encoding checkpoint 1 kinase, a key regulator of mitosis, was highly expressed after stimulation by LPS. Also, seven different aminoacyl-tRNA synthetases that play an essential role in protein synthesis were found to be highly expressed. In addition to stimulating genes involved in cell proliferation, the injected substances, especially LPS, also induced expression of a number of immune-related genes including arginase, peptidoglycan recognition protein short form, tumor necrosis factor receptor, ficolin, calmodulin, bacterial permeability increasing proteins and E3 ubiquitin-protein ligase. Importantly, significant up-regulation was observed in four GiMAP (GTPase of immunity-associated protein) genes, a result which provides the first evidence suggesting an immune role of Gi

  11. [Effects of eugenol and derivatives on Biomphalaria glabrata].

    Science.gov (United States)

    De Souza, C P; De Oliveira, A B; Araújo, N; Katz, N

    1991-05-01

    Biomphalaria glabrata snails and egg-masses were exposed, for six to twenty-four hours to concentrations of 1, 10, 100 and 1000 ppm of Eugenol, O-methyleugenol, O-benzyleugenol and dehydrodieugenol. Only at 10 ppm O-benzyleugenol enhanced mortality of snails and egg-masses. The other substances showed ovicidal and molluscicidal activity only at 100 and 1000 ppm concentrations, causing a significant cardiac frequency reduction in snails after 6 to 24 hours of exposure as well as perduring low cardiac rates until 24 hours afterwards. Two specimen exposed to 100 ppm O-methyleugenol presented anesthetic effect and extrusion of copulator and urethral organs. No schistosomicide or anesthetic effects were observed in mice experimentally infected with Schistosoma mansoni and treated during 5 days with oral doses of 150 mg/kg of Eugenol, O-methyleugenol and O-benzyleugenol. PMID:1844101

  12. The molluscicidal activity of niclosamide (Bayluscide WP70® on Melanoides tuberculata (Thiaridae, a snail associated with habitats of Biomphalaria glabrata (Planorbidae

    Directory of Open Access Journals (Sweden)

    Alexandre Giovanelli

    2002-07-01

    Full Text Available The aim of this study was to determine the toxicity of niclosamide (Bayluscide ® on Melanoides tuberculata and Biomphalaria glabrata under laboratory conditions. The latter species is the intermediate host of Schistosoma mansoni (Sambon 1917. M. tuberculata was successfully used as competitor of B. glabrata in biological control programs in French West Indies. Both molluscicide and biological control using M. tuberculata have proved to be successful in reducing the population density of B. glabrata. The associated use of molluscicide in this area would be an effective measure if M. tuberculata were less susceptibility to the molluscicide than B. glabrata. Three hundreds individuals each of B. glabrata and of M. tuberculata, collected in Sumidouro, State of Rio de Janeiro, were used in the experiment. The molluscs were exposed to 14 different concentrations of niclosamide as recommended by the World Health Organization. Probit analysis was used to determine the LC 50 and LC 90. The LC 50 and LC 90 values for B. glabrata were 0.077 mg/l and 0.175 mg/l, respectively and the LC 50 and LC 90 values for M. tuberculata were 0.082 mg/l and 0.221 mg/l respectively. As the lethal concentrations of niclosamide were approximately the same to both species, this could be a disadvantage when controlling B. glabrata with niclosamide in an area of M. tuberculata occurrence. It migth therefore be preferable to utilize the latex extracted from the Euphorbia splendens, which presented a much higher efficiency for B. glabrata than to M. tuberculata.

  13. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818) DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818)

    OpenAIRE

    Elaine Barros da Costa CARVALHO; Melo, Ana Maria Mendonça de Albuquerque; Mauricy Alves da MOTTA

    1999-01-01

    The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony...

  14. Isolation and characterization of the full-length cDNA encoding a member of a novel cytochrome p450 family (CYP320A1 from the tropical freshwater snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Anne E Lockyer

    2005-05-01

    Full Text Available Cytochrome p450s (cyp450s are a family of structurally related proteins, with diverse functions, including steroid synthesis and breakdown of toxins. This paper reports the full-length sequence of a novel cyp450 gene, the first to be isolated from the tropical freshwater snail Biomphalaria glabrata, an important intermediate host of Schistosoma mansoni. The nucleotide sequence is 2291 bp with a predicted amino acid sequence of 584aa. The sequence demonstrates conserved cyp450 structural motifs, but is sufficiently different from previously reported cyp450 sequences to be given a new classification, CYP320A1. Initially identified as down-regulated in partially resistant snails in response to S. mansoni infection, amplification of this gene using RT-PCR in both totally resistant or susceptible snail lines when exposed to infection, and all tissues examined, suggests ubiquitous expression. Characterization of the first cyp450 from B. glabrata is significant in understanding the evolution of these metabolically important proteins.

  15. A New Method for Fixing Biomphalaria glabrata for Histologic Studies, Using Shell Perforation

    OpenAIRE

    Barbosa Luciene; Coelho Paulo Marcos Z; Negrão-Corrêa Débora; Andrade Zilton A

    2002-01-01

    A new technique for fixation of Biomphalaria glabrata for histologic studies is described. It consists in performing several external holes in the shell, before placing the entire snail into the fixative. It is a very practical and quick procedure that showed excellent results when compared to the usual techniques.

  16. A comparative parasitologic study on Biomphalaria glabrata snail and C3H/He mice infected with human and murine isolates of Schistosoma mansoni derived from Sumidouro, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Nilcéa Freire

    2003-09-01

    Full Text Available Experiments were carried out to analyze the biological characteristics of two sympatric isolates of Schistosoma mansoni derived from humans and murines in a low endemic transmission area (Sumidouro county, state of Rio de Janeiro, Brazil. Sympatric reared-laboratory Biomphalaria glabrata and C3H/He mice were used as experimental hosts. Parameters assessed comprised: precercarial period, infectivity and mortality (snails, prepatent period, infectivity (percentage of cercariae maturation into adult worm and intestinal egg count (mice. The murine isolate showed a shorter precercarial period and higher infectivity than human isolate (p 0.05. These data suggest that both isolates are local sub-populations, providing support for the hypotheses that in a same biotope mixed populations or sub-populations circulate among their main host (human beings and/or rodent as an anfixenous infection.

  17. Weight loss and survival of Biomphalaria Glabrata deprived of water

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    Marc Vianey-Liaud

    1986-06-01

    Full Text Available Immature and mature Biomphalaria glabrata are kept out of water at relative humidities varying from 0 to 100%. When snails are submitted to a saturated atmosphere, they show a slow weight loss and survival may be long. If relative humidity (RH decreases, weight loss becomes important and survival is short. A reduced RH (0 to 65% produces similar effects. During desiccation, fasting has no noticeable effect; survival depends essentially on weight loss.Biomphalaria glabrata maduros ou imaturos são mantidos fora da água, variando a umidade de 0 a 100%. Quando caramujos são submetidos a uma atmosfera saturada, sofrem uma lenta perda de peso e a sobrevivência pode ser longa. Se a umidade relativa decresce, a perda de peso será importante e a sobrevida será abreviada. Uma umidade relativa de 0 a 65% pode produzir efeitos similares. Durante a dessecação, a privação de alimento não tem efeito notável, a sobrevivência dependendo essencialmente da perda de peso.

  18. Atividade moluscicida de alguns produtos naturais sobre Biomphalaria glabrata Molluscicide activity of some natural products on Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1986-03-01

    Full Text Available Foi avaliada, em laboratório, a ação moluscicida de extratos aquosos (macerado e fervido, hexânico e etanólico de Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata e Tibouchina scrobiculata. As soluções dos extratos obtidos foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratório, nas concentrações de 1, 10, 20, 200 e 1000ppm. Dos extratos testado o mais ativo foi o etanólico das flores da D. regia (flamboyant que apresentou atividade moluscicida sobre caramujos adultos na concentração de 20ppm.The molluscicide activity of aqueous (macerated and boiled, hexamic and ethylic extracts of Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata and Tibouchina scrobiculata was evaluated in the laboratory. The solutions obtained from those extracts were tested on adults and egg masses of Biomphalaria glabrata reared in the laboratory at 1, 10, 20, 100 and 1000ppm concentrations. The most active of the extracts studied was D. regia flowers' (flamboyant ethylic extracts which presented molluscicidal activity on adult snails at 20ppm.

  19. Repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida Repopulation of breeding habitats of Biomphalaria glabrata after treatment with niclosamide

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1991-08-01

    Full Text Available Experimentos foram feitos no laboratório e no campo nos anos de 1980 a 1984, objetivando detectar as causas do repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida. Os bioensaios no laboratório mostraram que a suscetibilidade à niclosamida emulsionável de B. glabrata coletada mensalmente em um sistema de valas de irrigação, variou durante o ano. As concentrações letais CL90 foram 0,15 mgl-1 a 0,60 mgl-1, apresentando diferenças significantes estatisticamente (p Experiments were undertaken both in the laboratory and in the field between 1980-1984 to evaluate the causes of repopulation of breeding places of Biomphalaria glabrata following treatment with Niclosamide. Laboratory bioassays showed that the susceptibility to emulsifiable Niclosamide of B. glabrata collected monthly from an irrigation ditch system varied during the year. Lethal concentrations (LC90 ranged between 0.15 mg/l-1 and 0.60 mg/l-1. Statistically significant differences (alpha=0.01 were evident between the months of May/82 and January/83 and December/82 and January/83, and were related to snail nutrition. In the field two types of foci of B. glabrata were treated with 10 ppm of Niclosamide. The first one consisted of a reservoir of 12000 1 of water in which 14.5% of snails were infected with Schistosoma mansoni. One application of molluscicide followed by cleaning of the reservoir eliminated all the snails. The second one consisted of an irrigation system in which 5.6% of the snails were infected with S. mansoni. One application of molluscicide without cleaning the ditches reduced the density of snails by 98%. The causes of the survival of 2.0% of the snails in the ditches are discussed in relation to the substratum of the breeding places and the treatment technique.

  20. A contribution to the pathobiology of Biomphalaria glabrata hemocytes

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    Claudia Maria da Cunha Borges

    2006-10-01

    Full Text Available This study attempts to investigate the relationship between the hemocytes in the two compartments: circulating peripheral lymph and the connective tissues. The hemocytes are compared with the vertebrate macrophages and constitute the principal line of defense against external aggression. The hemocytes were counted in circulating hemolymph and their phagocytic capability was evaluated in Schistosoma mansoni-infected Biomphalaria glabrata and the results were compared with those obtained from normal intact control snails. Although the number of circulating hemocytes revealed a mild increase in snails at the 6th week of infection, the overall findings were similar and pointed out that the cells in the two compartments are not functionally connected. However, the hemocytes found within the connective tissues of infected snails showed definite ultrastructural differences in the number and disposition of cytoplasmic prolongations and organelles in comparison with the hemocytes from non-infected snails. Histochemically, the staining for acid phosphatase activity served as a marker to hemocytes, sometimes being found in extracellular material at the foci of parasite-hemocyte interactions.

  1. On the origin of the Biomphalaria glabrata hemocytes

    Directory of Open Access Journals (Sweden)

    Samaly dos Santos Souza

    2006-10-01

    Full Text Available A histologic, morphometric and ultrastructural study performed on Biomphalaria glabrata submitted to infection with Schistosoma mansoni miracidia failed to provide significant evidences that the so-called amebocyte-producing organ (APO is really the central organ for hemocyte production. In infected snails no general reactive changes appeared in the APO, the mitoses were seen only occasionally, and the possibility of cellular hyperplasia was ruled out by morphometric measurements. Under the electron microscope the APO cells presented an essentially epithelial structure, without features indicative of transition toward hemocytes. On the other hand, the present findings pointed to a multicentric origin for the mollusck hemocytes, as earlier studies had indicated. Dense foci of hemocyte collections appeared sometimes around disintegrating sporocysts and cercariae in several organs and tissues of the infected snails, including a curious accumulation of such cells inside the ventricular cavity of the heart. In the heart and other sites, features suggestive of transformation of vascular space endothelial lining cells into hemocytes were apparent. To some extent, the postulated multicentric origin for B. glabrata hemocytes recapitulates earlier embryologic findings in vertebrates, when mesenchymal vascular spaces generate the circulating and phagocytic blood cells.

  2. Differential lectin labelling of circulating hemocytes from Biomphalaria glabrata and Biomphalaria tenagophila resistant or susceptible to Schistosoma mansoni infection

    Directory of Open Access Journals (Sweden)

    RL Martins-Souza

    2006-10-01

    Full Text Available Lectins/carbohydrate binding can be involved in the Schistosoma mansoni recognition and activation of the Biomphalaria hemocytes. Therefore, expression of lectin ligands on Biomphalaria hemocytes would be associated with snail resistance against S. mansoni infection. To test this hypothesis, circulating hemocytes were isolated from B. glabrata BH (snail strain highy susceptible to S. mansoni, B. tenagophila Cabo Frio (moderate susceptibility, and B. tenagophila Taim (completely resistant strains, labelled with FITC conjugated lectins (ConA, PNA, SBA, and WGA and analyzed under fluorescence microscopy. The results demonstrated that although lectin-labelled hemocytes were detected in hemolymph of all snail species tested, circulating hemocytes from both strains of B. tenagophila showed a larger number of lectin-labelled cells than B. glabrata. Moreover, most of circulating hemocytes of B. tenagophila were intensively labelled by lectins PNA-FITC and WGA-FITC, while in B. glabrata small hemocytes were labeled mainly by ConA. Upon S. mansoni infection, lectin-labelled hemocytes almost disappeared from the hemolymph of Taim and accumulated in B. glabrata BH. The role of lectins/carbohydrate binding in resistance of B. tengophila infection to S. mansoni is still not fully understood, but the data suggest that there may be a correlation to its presence with susceptibility or resistance to the parasite.

  3. Circulating Biomphalaria glabrata hemocyte subpopulations possess shared schistosome glycans and receptors capable of binding larval glycoconjugates

    OpenAIRE

    YOSHINO, TIMOTHY P.; Wu, Xiao-Jun; Gonzalez, Laura A.; Cornelis H Hokke

    2012-01-01

    Host lectin-like recognition molecules may play an important role in innate resistance in Biomphalaria glabrata snails to larval schistosome infection, thus implicating parasite-expressed glycans as putative ligands for these lectin receptors. While host lectins may utilize specific glycan structures for parasite recognition, it also has been hypothesized that the parasite may use this system to evade immune detection by mimicking naturally-expressed host glycans, resulting in reduced immunor...

  4. Effects of Plagiorchis elegans (Digenea: Plagiorchiidae) infection on the reproduction of Biomphalaria glabrata (Pulmonata: Planorbidae).

    Science.gov (United States)

    Zakikhani, M; Rau, M E

    1998-10-01

    Infection with the digenean parasite Plagiorchis elegans dramatically reduced the reproductive output of Biomphalaria glabrata exposed to the parasite as juveniles or adults. The total number of eggs produced by infected snails was reduced to approximately 7 and 13% of control values, respectively. Parasitic castration was attributed to the presence of mother sporocysts that readily established in the tissues of this incompatible host. Infection did not result in the production of cercariae but significantly shortened the life span of juvenile and adult B. glabrata by approximately 23 and 10%, respectively. Plagiorchis elegans also castrated its compatible host, Stagnicola elodes. PMID:9794632

  5. New insights into the amphibious life of Biomphalaria glabrata and susceptibility of its egg masses to fungal infection

    Science.gov (United States)

    Egg masses of an aquatic snail, Biomphalaria glabrata, matured, and juveniles subsequently eclosed and were mobile in a stable water film of transitory habitats simulated by two different simple test devices described here. The viability of eggs maintained in an unstable film due to low ambient mois...

  6. Contribution to the histology of Biomphalaria glabrata Contribuição à histologia da Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Queli Teixeira Lemos

    1999-08-01

    Full Text Available A combination of histological techniques applied to the study of Biomphalaria glabrata yielded some interesting new data about the histology of this snail, a major intermediate host of Schistosoma mansoni in Brazil. Three kinds of pigments were identified: a dark pigment which bleached following oxidation with potassium permanganate; a lipofuchsin-like, diastase-resistant PAS-positive pigment and an iron-containing pigment, probably related to hemosiderin. Calcium was detected in small deposits within the connective tissue and forming a dense core inside the chitinous radular teeth. The presence of fibrils, staining with sirius-red and birefringence under polarized light strongly suggest primitive collagen tissue. The radular apparatus appeared as a storing site for glycogen, while abundant Alcian-blue positive material (proteoglycans was extremely concentrated in the radular sac.Uma combinação de várias técnicas histológicas permitiu alguns achados de interesse para a histologia da Biomphalaria glabrata, principal hospedeiro intermediário do Schistosoma mansoni no Brasil. Três tipos de pigmentos foram identificados: um pigmento escuro, que se descora após oxidação pelo permanganato de potássio; outro que é semelhante à lipofuscina, que se cora pelo PAS e é diastase- resistente, e um pigmento que contém ferro, provalvelmente, relacionado com a hemossiderina. O cálcio foi identificado em pequenos depósitos no interior do tecido conjuntivo e formando pequenos núcleos no interior dos dentes quitinosos da rádula. A presença de fibrilas coradas pelo sírius-vermelho, exibindo birrefrigência sob luz polarizada, sugere fortemente a presença de um tecido colágeno primitivo. O aparelho radular foi visto como um local de armazenamento do glicogênio, enquanto a presença de abundante material amorfo positivo para o azul de alciano (proteoglicano apareceu em grande concentração no saco radular.

  7. A Novel Bacterial Pathogen of Biomphalaria glabrata: A Potential Weapon for Schistosomiasis Control?

    Science.gov (United States)

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean François; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2015-01-01

    Background Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects. Methodology/Principal findings In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs. Conclusions/Significance This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field. PMID:25719489

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

    OpenAIRE

    Cecília Pereira de Souza; Neusa Araújo; Liana Konovaloff Jannotti-Passos; Carlos Tito Guimarães

    1994-01-01

    The snail density, levels of infection and the monthly production of Schistosoma mansoni cercariae by Biomphalaria glabrata were determined in a focus of Barreiro de Baixo (Belo Horizonte, MG, Brazil). During a period of 38 months (1984 to 1987) 5,366 snails were collected of which 324 (6.03%) were infected with S. mansoni. The total number of cercariae shed was 5,667,312. Each snail shed an average of 17,422 cercariae during the time that it was under study in the laboratory. The greatest lo...

  9. OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST

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    Ludmila Nakamura Rapado

    2013-12-01

    Full Text Available SUMMARY Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively.

  10. OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST

    Science.gov (United States)

    Rapado, Ludmila Nakamura; Lopes, Priscila Orechio de Moraes; Yamaguchi, Lydia Fumiko; Nakano, Eliana

    2013-01-01

    SUMMARY Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively). PMID:24213196

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

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    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.

  12. 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.

  13. Altered Gene Expression in the Schistosome-Transmitting Snail Biomphalaria glabrata following Exposure to Niclosamide, the Active Ingredient in the Widely Used Molluscicide Bayluscide

    OpenAIRE

    Zhang, Si-Ming; Buddenborg, Sarah K; Adema, Coen M.; Sullivan, John T.; Loker, Eric S

    2015-01-01

    In view of the call by the World Health Organization (WHO) for elimination of schistosomiasis as a public health problem by 2025, use of molluscicides in snail control to supplement chemotherapy–based control efforts is likely to increase in the coming years. The mechanisms of action of niclosamide, the active ingredient in the most widely used molluscicides, remain largely unknown. A better understanding of its toxicology at the molecular level will both improve our knowledge of snail biolog...

  14. The relationship between genetic variability and the susceptibility of Biomphalaria alexandrina snails to Schistosoma mansoni infection

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    Azza H Mohamed

    2012-05-01

    Full Text Available In the present study, Biomphalaria snails collected from five Egyptian governorates (Giza, Fayoum, Kafr El-Sheikh, Ismailia and Damietta, as well as reference control Biomphalaria alexandrina snails from the Schistosome Biological Supply Center (SBSC (Theodor Bilharz Research Institute, Egypt, were subjected to species-specific polymerase chain reaction (PCR assays to identify the collected species. All of the collected snails were found to be B. alexandrina and there was no evidence of the presence of Biomphalaria glabrata. Randomly amplified polymorphic DNA (RAPD-PCR assays showed different fingerprints with varying numbers of bands for the first generation (F1 of B. alexandrina snail populations (SBSC, Giza, Fayoum, Kafr El-Sheikh, Ismailia and Damietta. The primer OPA-1 produced the highest level of polymorphism and amplified the greatest number of specific bands. The estimated similarity coefficients among the B. alexandrina populations based on the RAPD-PCR profiles ranged from 0.56 (between SBSC and Ismailia snails to 0.72 (between Ismailia and Kafr El-Sheikh snails. Experimental infection of the F1 of progeny from the collected snails with Schistosoma mansoni (SBSC strain showed variable susceptibility rates ranging from 15% in the Fayoum snail group to 50.3% in SBSC snails. A negative correlation was observed between the infection rates in the different snail groups and the distances separating their corresponding governorates from the parasite source. The infection rates of the snail groups and their similarity coefficients with SBSC B. alexandrina snails were positively correlated. The variations in the rates of infection of different B. alexandrina groups with S. mansoni, as well as the differences in the similarity coefficients among these snails, are dependent not only on the geographical distribution of the snails and the parasite, but also on the genetic variability of the snails. Introduction of this variability into endemic

  15. The role of behavior in the survival of Biomphalaria glabrata in biossays with the plant molluscicide Phytolacca dodecandra O papel do comportamento na sobrevivência de Biomphalaria glabrata submetida a bioensaios com o moluscicida vegetal Phytolacca dodecandra

    OpenAIRE

    P. Jurberg; J. V. Barbosa; Rotenberg, L.

    1988-01-01

    This work examines the role of behavior in the survival of Biomphalaria glabrata exposed to 25, 50 75 and 100 mgl-1 of Phytolacca dodecandra. Time-lapse cinematography was used to quantify accurately the following parameters: (a) frequency of exits from the solution, (b) time spent out of the solution and (c) time elapsed until the first exit from the solution. These behavior patterns were statistically compared between surviving snails and those which later died. The proportion of surviving ...

  16. Atividade moluscicida do extrato butílico de Phytolaca dodecandra (Endod sobre Biomphalaria glabrata Molluscicide activity of a buthanol extract of Phytolacca dodecandra (Endod on Biomphalaria glabrata

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    Cecília Pereira de Souza

    1987-09-01

    Full Text Available O extrato butílico da Phytolacca dodecandra (tipo 44 obtido de frutos procedentes da Etiópia, foi testado como moluscicida em nosso laboratório e no campo. As concentrações letais, CL90, com 24 horas de exposição, para Biomphalaria glabrata adulta, recém-eclodidas e desovadas foram de 4,5, 23,0 e 102,0 ppm, respectivamente. Para peixes, Lebistes reticulatus, a CL90 foi de 2,0 ppm. Esses resultados foram semelhantes aos obtidos por Lemma em 1984, na Etiópia. Em dois criadouros com água parada, tratados com 10ppm de estrato butílico e 3ppm de niclosamida, ocorreu 84,0 e 100,0% de mortalidade B. glabrata, respectivamente. Os dois produtos foram tóxicos para peixes (L. reticulatus no campo. É discutida a possibilidade do uso de moluscidas de origem vegetal, como alternativa para o combate a focos de esquistossomose no Brasil.A buthanol extract of Phytolacca dodecandra (type 44 obtained from Ethiopia berries, was tested as molluscicide in our laboratory and in the field. The lethal dose (LD90 for adult snails, newly hatched and egg-masses of Biomphalaria glabrata, in 24 hours exposure, were of 4.5, 23.0 and 102.0 ppm respectively. The LD90 for the fish Lebistes reticulatus was of 2.0 ppm. These results are similar to those of Lemma (1984 in Ethiopia. In two water ponds treated with 10 ppm of the buthanol extract or 3 ppm of niclosamide the mortality rates of B. glabrata were of 84.6 and 100.0%, respectively. Both treatments were toxic for L. reticulatus in the field trials. The possibility of using molluscicides derived from plants is discussed as an alternative for treatment of schistosomiasis foci in Brazil.

  17. 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...

  18. Rheotaxis of Biomphalaria glabrata on vertical substrates and its role in the recolonization of habitats treated with molluscicides

    OpenAIRE

    P. Jurberg; C. L. P. A. Coelho da Silva; M. G. M. Barreto; Soares, M. S.

    1988-01-01

    The authors observed specimens of Biomphalaria glabrata climbing up the vertical wall of a ditch against the current. The snails that showed this behavior during application of a molluscicide in the breeding site survived and probably played a role in repopulation, which was observed three months later. These observations motivated field and laboratory investigations which led the authors to conclude that: a) this species is able to climb vertical surfaces both in field and laboratory situati...

  19. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of 60Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD50 obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  20. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  1. Avaliação da bioatividade dos extratos de cúrcuma (Curcuma longa L., Zingiberaceae em Artemia salina e Biomphalaria glabrata Bioactivity evaluation of the turmeric (Curcuma longa L., Zingiberaceae extracts in Artemia salina and Biomphalaria glabrata

    Directory of Open Access Journals (Sweden)

    Carlos R. M. da Silva Filho

    2009-12-01

    Full Text Available A cúrcuma é o rizoma limpo, em boas condições, seco e moído da Curcuma longa L., uma planta herbácea da família Zingiberaceae. Visando novas alternativas para o controle da esquistossomose, os extratos de Curcuma longa L. foram testados para a avaliação da atividade moluscicida contra caramujos adultos da espécie Biomphalaria glabrata, e toxicidade (ensaio de letalidade com Artemia salina. A oleoresina e o óleo essencial de cúrcuma foram ativos contra Artemia salina (CL50 = 80,43 e CL50 = 319,82 μg/mL, respectivamente e também ativos contra os indivíduos adultos de Biomphalaria glabrata (CL50 = 58,3 e CL50 = 46,73 μg/mL, respectivamente. A partir dos resultados obtidos pôde ser concluído que ambos os extratos podem constituir uma alternativa no controle da população desses caramujos e na redução da esquistossomose.The turmeric is the clean rhizome at good conditions, dried and powdered of Curcuma longa L., an herbaceous plant of Zingiberaceae family. Aiming new alternatives for Schistosomiasis control, the Curcuma longa L. extracts were tested for molluscicidal activity evaluation against adult snails of Biomphalaria glabrata specie, and the toxicity (Brine Shrimp Lethality-BSL-bioassay. The oleoresin and the essential oil of turmeric were active against Artemia salina (CL50 = 80.43 and CL50 = 319.82 μg.mL-1, respectively and also active against the adult snails of Biomphalaria glabrata (CL50 = 58.3 and CL50 = 46.73 μg.mL-1, respectively. From the obtained results it was concluded that both extracts can constitute an alternative to population control of these snails and in the reduction of Schistosomiasis.

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

    Directory of Open Access Journals (Sweden)

    Clélia Christina Mello-Silva

    2010-07-01

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

  3. Comparative Histopathology of Biomphalaria glabrata, B. tenagophila and B. straminea with Variable Degrees of Resistance to Schistosoma mansoni Miracidia

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    Cecilia Pereira de Souza

    1997-07-01

    Full Text Available A comparative histopathological study of three snails species - Biomphalaria glabrata, B. tenagophila and B. straminea - which had been infected with Schistosoma mansoni miracidia revealed similar qualitative features, consisting of areas of sporocyst proliferation and differentiation associated with reactive host reaction, at the time they were actively eliminating great number of cercariae. However, in specimens that were exposed to miracidia but failed to eliminate cercariae later on, different histopathological pictures were observed in different snail species. While B. glabrata exhibited frequent focal (granulomatous proliferation of amebocytes in several organs, B. tenagophila and B. straminea only rarely showed such reactive changes, suggesting that the mechanism of resistance to miracidial infection probably follows different pathways in the snail species studied

  4. Gamma 60 Co D L 50/30 of Biomphalaria glabrata (Say, 1818)

    International Nuclear Information System (INIS)

    The variation of resistance to 60 Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60 Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  5. Gamma {sup 60} Co D L {sub 50/30} of Biomphalaria glabrata (Say, 1818)

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Elaine Barros da Costa; Melo, Ana Maria Mendonca de Albuquerque; Motta, Mauricy Alves da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1999-12-01

    The variation of resistance to {sup 60} Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose) to increasing doses of gamma radiation. Doses of 10, 20 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell {sup 60} Co irradiator, were applied to the test groups and two groups control (non-irradiated) of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL{sub 50/30}=218.2 Gy) was found greater than in cross-fecundation forms. These data point to allow radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon. (author)

  6. Atividade moluscicida de alguns produtos naturais sobre Biomphalaria glabrata Molluscicide activity of some natural products on Biomphalaria glabrata

    OpenAIRE

    Nelymar Martineli Mendes; Cecília Pereira de Souza; Neusa Araújo; José Pedro Pereira; Naftale Katz

    1986-01-01

    Foi avaliada, em laboratório, a ação moluscicida de extratos aquosos (macerado e fervido), hexânico e etanólico de Aristolochia brasiliensis, Caesalpinia peltophoroides, Caesalpinia pulcherrima, Delonix regia, Spathodea campanulata e Tibouchina scrobiculata. As soluções dos extratos obtidos foram testadas sobre caramujos adultos e desovas de Biomphalaria glabrata, criados em laboratório, nas concentrações de 1, 10, 20, 200 e 1000ppm. Dos extratos testado o mais ativo foi o etanólico das flore...

  7. Rescue of sporocysts of Schistosoma mansoni in nonsusceptible Biomphalaria by head-foot transplantation into susceptible snails.

    Science.gov (United States)

    Galvan, A G; Paugam, M; Sullivan, J T

    2000-04-01

    To measure the longevity of sporocysts of Schistosoma mansoni in nonsusceptible snails (13-16-R1 and Salvador strains of Biomphalaria glabrata, and Biomphalaria obstructa), the head-foot (HF) of miracidia-exposed snails was transplanted into the hemocoel of a susceptible NIH albino recipient at 1-36 days postexposure (DPE). Recipient snails which were not exposed to miracidia then were monitored for infection transferred by the implant, and infection prevalences in recipients of HF transplants from nonsusceptible donors were compared to those in snails implanted with an HF from NIH albino donors. Transplants from NIH albino snails between 1 to 15 DPE infected 98% of recipients. Similarly, at 1 DPE, 69-85% of transplants from nonsusceptible snails contained viable sporocysts, as shown by resulting patent infections in the recipients. Recipient infection prevalence, and presumably numbers of transplants containing viable sporocysts, declined as a function of DPE, and by 5-9 DPE this decrease was significant for all 3 types of nonsusceptible donors. However, viable sporocysts still occurred in B. obstructa and 13-16-R1 B. glabrata as late as 19 and 20 DPE, respectively, and in Salvador B. glabrata as late as 33 DPE. Thus, sporocysts persist in nonsusceptible snails considerably longer than suggested by results of previous histological studies. PMID:10780550

  8. Usnic Acid Potassium Salt: An Alternative for the Control of Biomphalaria glabrata (Say, 1818)

    Science.gov (United States)

    Lima, Vera L. M.; Pereira, Eugênia C.; Falcão, Emerson P. S.; Melo, Ana M. M. A.; da Silva, Nicácio Henrique

    2014-01-01

    In Brazil, the snail Biomphalaria glabrata is the most important vector of schistosomiasis due to its wide geographical distribution, high infection rate and efficient disease transmission. Among the methods of schistosomiasis control, the World Health Organization recommends the use of synthetic molluscicides, such as niclosamide. However, different substances of natural origin have been tested as alternatives for the control or eradication of mollusks. The literature describes the antitumor, antimicrobial and antiviral properties of usnic acid as well as other important activities of common interest between medicine and the environment. However, usnic acid has a low degree of water solubility, which can be a limiting factor for its use, especially in aquatic environments, since the organic solvents commonly used to solubilize this substance can have toxic effects on aquatic biota. Thus, the aim of the present study was to test the potassium salt of usnic acid (potassium usnate) with regard to molluscicidal activity and toxicity to brine shrimp (Artemia salina). To obtain potassium usnate, usnic acid was extracted with diethyl ether isolated and purified from the lichen Cladonia substellata. Biological assays were performed with embryos and adult snails of B. glabrata exposed for 24 h to the usnate solution solubilized in dechlorinated water at 2.5; 5 and 10 µg/ml for embryos, 0.5; 0.9; 1;5 and 10 µg/ml for mollusks and 0.5; 1; 5; 10 µg/ml for A. salina. The lowest lethal concentration for the embryos and adult snails was 10 and 1 µg/ml, respectively. No toxicity to A. salina was found. The results show that modified usnic acid has increased solubility (100%) without losing its biological activity and may be a viable alternative for the control of B. glabrata. PMID:25375098

  9. Usnic acid potassium salt: an alternative for the control of Biomphalaria glabrata (Say, 1818.

    Directory of Open Access Journals (Sweden)

    Mônica C B Martins

    Full Text Available In Brazil, the snail Biomphalaria glabrata is the most important vector of schistosomiasis due to its wide geographical distribution, high infection rate and efficient disease transmission. Among the methods of schistosomiasis control, the World Health Organization recommends the use of synthetic molluscicides, such as niclosamide. However, different substances of natural origin have been tested as alternatives for the control or eradication of mollusks. The literature describes the antitumor, antimicrobial and antiviral properties of usnic acid as well as other important activities of common interest between medicine and the environment. However, usnic acid has a low degree of water solubility, which can be a limiting factor for its use, especially in aquatic environments, since the organic solvents commonly used to solubilize this substance can have toxic effects on aquatic biota. Thus, the aim of the present study was to test the potassium salt of usnic acid (potassium usnate with regard to molluscicidal activity and toxicity to brine shrimp (Artemia salina. To obtain potassium usnate, usnic acid was extracted with diethyl ether isolated and purified from the lichen Cladonia substellata. Biological assays were performed with embryos and adult snails of B. glabrata exposed for 24 h to the usnate solution solubilized in dechlorinated water at 2.5; 5 and 10 µg/ml for embryos, 0.5; 0.9; 1;5 and 10 µg/ml for mollusks and 0.5; 1; 5; 10 µg/ml for A. salina. The lowest lethal concentration for the embryos and adult snails was 10 and 1 µg/ml, respectively. No toxicity to A. salina was found. The results show that modified usnic acid has increased solubility (100% without losing its biological activity and may be a viable alternative for the control of B. glabrata.

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

    Science.gov (United States)

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

    2015-08-01

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

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

    Science.gov (United States)

    Kloos, Helmut; Passos, Liana Kanovaloff Janotti; Loverde, Philip; Oliveira, Rodrigo Correa; Gazzinelli, Andréa

    2004-11-01

    This paper examines the distribution and infection of Biomphalaria glabrata with Schistosoma mansoni in all aquatic snail habitats in a rural area in the state of Minas Gerais, Brazil, in relation to physico/biotic and behavioral factors. Snail and environmental surveys were carried out semi-annually between July 2001 and November 2002 at 106 sites. Collected snails were examined in the laboratory for infection. B. glabrata densities were highest in overflow ponds, irrigation ponds, springs, canals and wells, and lowest in fishponds and water tanks. Snail densities were higher during the hot, rainy season except for streams and canals and were statistically associated with the presence of fish, pollution, and vegetation density. Tilapia fish and an unidentified Diptera larva were found to be predators of B. glabrata but ducks were not. Twenty-four of the 25 infected snails were collected in 2001(1.4% infection rate) and only one in 2002, after mass chemotherapy. The occurrence of B. glabrata in all 11 snail habitats both at and away from water contact sites studied indicates widespread risk of human infection in the study area. In spite of the strong association between B. glabrata and tilapia in fishponds we do not recommend its use in schistosomiasis control for ecological reasons and its relative inefficiency in streams and dams. PMID:15654420

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

    Directory of Open Access Journals (Sweden)

    Helmut Kloos

    2004-11-01

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

  13. The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: implications for developing new model organisms.

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    Satwant Kaur

    Full Text Available Nuclear receptors (NRs are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully sequenced genome of the gastropod snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni and compare these to known vertebrate NRs, with a view to assessing the snail's potential as a invertebrate model organism for endocrine function, both as a prospective new test organism and to elucidate the fundamental genetic and mechanistic causes of disease. For comparative purposes, the genome of a second gastropod, the owl limpet, Lottia gigantea was also investigated for nuclear receptors. Thirty-nine and thirty-three putative NRs were identified from the B. glabrata and L. gigantea genomes respectively, based on the presence of a conserved DNA-binding domain and/or ligand-binding domain. Nuclear receptor transcript expression was confirmed and sequences were subjected to a comparative phylogenetic analysis, which demonstrated that these molluscs have representatives of all the major NR subfamilies (1-6. Many of the identified NRs are conserved between vertebrates and invertebrates, however differences exist, most notably, the absence of receptors of Group 3C, which includes some of the vertebrate endocrine hormone targets. The mollusc genomes also contain NR homologues that are present in insects and nematodes but not in vertebrates, such as Group 1J (HR48/DAF12/HR96. The identification of many shared receptors between humans and molluscs indicates the potential for molluscs as model organisms; however the absence of several steroid hormone receptors indicates snail endocrine systems are fundamentally different.

  14. Gamma 60Co DL50/30 of Biomphalaria glabrata (Say, 1818 DL50/30 raios gama de 60Co em Biomphalaria glabrata (Say, 1818

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    Elaine Barros da Costa CARVALHO

    1999-11-01

    Full Text Available The variation of resistance to 60Co gamma-rays of Biomphalaria glabrata was studied. A population of 480 mollusks was observed during 30 days - distributed in 8 groups of snails isolated and 8 groups of snails in colonies - after exposure (30 snails per group per dose to increasing doses of gamma radiation. Doses of 10, 20, 40, 60, 80, 160, 320 and 640 Gy from a Gamma-cell 60Co irradiator, were applied to the test groups and two groups control (non-irradiated of snails - isolated and colony - were kept apart. After have been exposed, the snails were drew back to the aquaria where they were maintained before. The survival was estimated on a daily score of the alive animals in each group-dose, starting after the irradiation exposure day. As a result, the survival self-fertilization forms (DL50/30 = 218.2 Gy was found greater than in cross-fecundation forms. These data point to a low radio-resistance on the cross-fertilization forms - the sexual reproductive form - which is most found in nature. The lower radio-resistance of the cross-fertilization forms suggests the presence of some sex-linked hormonal factor related to this phenomenon.A variação da resistência entre indivíduos em autofecundação e fecundação cruzada de Biomphalaria glabrata foram estudadas. Uma população de 480 moluscos foi observada durante 29 dias, distribuída em 8 grupos de caramujos isolados e 8 grupos em colônias após a exposição (30 caramujos por grupo-dose a doses crescentes de radiação gama. Foram usadas doses de 10, 20, 40, 60, 80, 160, 320 e 640 Gy de um irradiador Gamma-Cell 60Co. Dois grupos não irradiados - isolado e colônia - foram separados como controle e após a irradiação todos os caramujos voltaram para aquários onde viviam antes. A sobrevida foi estimada pela contagem diária dos animais vivos em cada grupo-dose, a partir do dia da irradiação. O resultado mostrou maior sobrevivência nos grupos isolados (DL50/30 = 218.2 Gy que nos grupos

  15. Effect of Niclosamide (Bayluscide WP 70 (R)), Anacardium occidentale hexane extract and Euphorbia splendens latex on behavior of Biomphalaria glabrata (Say, 1818), under laboratory conditions

    OpenAIRE

    Pedro Jurberg; Otília Sarquis; José Augusto A dos Santos; Regina da Conceição Reis Ferreira

    1995-01-01

    The repellent effect of the molluscicides Niclosamide (Bayluscide WP 70 (R)), Anacardium occidentale and the latex of Euphorbia splendens on Biomphalaria glabrata was observed through the investigation of the occurrence of escape behavior among molluscs that were exposed to dosages lower than the LD 50. The total number of individuals out of water among the surviving snails in the control group provided a "Natural Escape Index". The comparison between this total and the total number of surviv...

  16. Effect of 60 Co gamma radiation on Biomphalaria Glabrata (Mollusca, Gastropoda) embryos: mortality, malformation and hatching

    International Nuclear Information System (INIS)

    A study was carried out on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10, 15, 20 and 25 Gy of 60 Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality, malformation and hatching were the parameters used to evaluate the damage induced by ionizing radiation. Estimated L D50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). Susceptibility to malformation induction was higher in the blastula, gastrula and young trochophore stages. Several types of morphogenetic malformations were observed, such as head malformations, exogastrulas, shell malformations, and embryos with everted stomodeum, with nonspecific malformations being the most frequent. The types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied. The dose of 15 Gy was sufficient to greatly reduce the number of hatching snails regardless of the embryonic stage irradiated. We conclude that the effect of 60 Co gamma radiation on B. glabrata embryos presented a specific pattern. (author)

  17. Estudo quantitativo de metais presentes na hemolinfa de Biomphalaria glabrata (Gastropoda, infectadas e não infectadas com Schistosoma mansoni Quantitative study of metal present in the hemolymph of Biomphalaria glabrata (Gastropoda, infected and uninfected with Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Marco Antonio Vasconcelos Santos

    2005-04-01

    Full Text Available Inicialmente, desenvolveu-se um estudo para quantificar e comparar as concentrações de alguns metais presentes em duas amostras de hemolinfa do caramujo Biomphalaria glabrata (infectados e não-infectados com Schistosoma mansoni. A espectrometria de emissão óptica com fonte de plasma induzido (ICP-OES, foi utilizada para analisar os metais nas duas amostras. Os metais estudados foram: alumínio, cálcio, cádmio, cobalto, cromo, cobre, ferro, potássio, magnésio, manganês, chumbo e zinco. Os resultados mostram que, a princípio, os metais não são fatores determinantes no processo de defesa desses organismos contra este parasita, quando presente nos seus tecidos.We conducted a preliminary study to quantify and compare two concentrations of the same metals present in the hemolymph of snail Biomphalaria glabrata. In this context, we used Induction Coupled Plasma Optical Emission Spectroscopy technique (ICP-OES, to analyze the metals in the two samples (snails infected and not infected with Schistosoma mansoni. The metals studied were: aluminum, calcium, cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, lead and zinc. Preliminary results showed that such metals are not involved in the defense of these organisms against the parasite, when present in their tissues.

  18. A Novel Toll-Like Receptor (TLR) Influences Compatibility between the Gastropod Biomphalaria glabrata, and the Digenean Trematode Schistosoma mansoni.

    Science.gov (United States)

    Pila, Emmanuel A; Tarrabain, Mahmoud; Kabore, Alethe L; Hanington, Patrick C

    2016-03-01

    Schistosomiasis, a devastating disease caused by parasitic flatworms of the genus Schistosoma, affects over 260 million people worldwide especially in tropical and sub-tropical regions. Schistosomes must undergo their larval development within specific species of snail intermediate hosts, a trait that is shared among almost all digenean trematodes. This unique and long-standing host-parasite relationship presents an opportunity to study both the importance of conserved immunological features in novel immunological roles, as well as new immunological adaptations that have arisen to combat a very specific type of immunological challenge. While it is well supported that the snail immune response is important for protecting against schistosome infection, very few specific snail immune factors have been identified and even fewer have been functionally characterized. Here, we provide the first functional report of a snail Toll-like receptor, which we demonstrate as playing an important role in the cellular immune response of the snail Biomphalaria glabrata following challenge with Schistosoma mansoni. This TLR (BgTLR) was identified as part of a peptide screen of snail immune cell surface proteins that differed in abundance between B. glabrata snails that differ in their compatibility phenotype to challenge by S. mansoni. The S. mansoni-resistant strain of B. glabrata (BS-90) displayed higher levels of BgTLR compared to the susceptible (M-line) strain. Transcript expression of BgTLR was found to be very responsive in BS-90 snails when challenged with S. mansoni, increasing 27 fold relative to β-actin (non-immune control gene); whereas expression in susceptible M-line snails was not significantly increased. Knockdown of BgTLR in BS-90 snails via targeted siRNA oligonucleotides was confirmed using a specific anti-BgTLR antibody and resulted in a significant alteration of the resistant phenotype, yielding patent infections in 43% of the normally resistant snails, which

  19. Steroid Androgen Exposure during Development Has No Effect on Reproductive Physiology of Biomphalaria glabrata

    Science.gov (United States)

    Lockyer, Anne E.; Routledge, Edwin J.; Jones, Catherine S.; Noble, Leslie R.; Jobling, Susan

    2016-01-01

    Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment. PMID:27448327

  20. Lamella formation and emigration from the water by a laboratory colony of Biomphalaria glabrata (SAY in flow-through system

    Directory of Open Access Journals (Sweden)

    Ricardo D. A. Dannemann

    1992-01-01

    Full Text Available Lamella formation and emigration from the water were investigated in juvenile Biomphalaria glabrata reared at two temperatures in aquaria with a constant water flow. Most snails (97.4% reared at the lower temperature (21- C formed lamella at the shell aperture and emigrated from the water, whereas only 10.1% did so at 25- C. Eighty percent of emigrations at 21- C occurred within a period of 15 days, 70-85 days after hatching. A comparison of the studies done so far indicates that the phenomenon may be affected by the ageing of snail colonies kept in the laboratory and their geographic origin, rather than the rearing conditions. This hypothesis, however, requires experimental confirmation.

  1. Circulating Biomphalaria glabrata hemocyte subpopulations possess shared schistosome glycans and receptors capable of binding larval glycoconjugates.

    Science.gov (United States)

    Yoshino, Timothy P; Wu, Xiao-Jun; Gonzalez, Laura A; Hokke, Cornelis H

    2013-01-01

    Host lectin-like recognition molecules may play an important role in innate resistance in Biomphalaria glabrata snails to larval schistosome infection, thus implicating parasite-expressed glycans as putative ligands for these lectin receptors. While host lectins may utilize specific glycan structures for parasite recognition, it also has been hypothesized that the parasite may use this system to evade immune detection by mimicking naturally-expressed host glycans, resulting in reduced immunorecognition capacity. By employing immunocytochemical (ICC) and Western blot assays using schistosome glycan-specific monoclonal antibodies (mABs) we sought to identify specific glycan epitopes (glycotopes) shared in common between larval Schistosoma mansoni and B. glabrata hemocytes, the primary immune effector cells in snails. Results confirmed the presence of selected larval glycotopes on subpopulations of hemocytes by ICC and association with numerous hemocyte proteins by Western blot analyses, including a trimannosyl core N-glycan (TriMan), and two fucosylated lacdiNAc (LDN) variants, F-LDN and F-LDN-F. Snail strain differences were seen in the prevalence of constitutively expressed F-LDN on hemocytes, and in the patterns of protein immunoreactivity with these mABs. In contrast, there was little to no hemocyte reactivity with mABs for Lewis X (LeX), LDN, LDN-F or LDN-DF. When intact hemocytes were exposed to larval transformation products (LTPs), distinct cell subpopulations displayed weak (LeX, LDN-DF) to moderate (LDN, LDN-F) glycotope reactivity by ICC, including snail strain differences in the prevalence of LDN-reactive cellular subsets. Far-Western blot analyses of the hemocytes following exposure to larval transformation proteins (LTPs) also revealed multiple mAB-reactive hemocyte protein bands for LeX, LDN, LDN-F, and LDN-DF. These results demonstrate the existence of complex patterns of shared larval glycan constitutively expressed on hemocytes and their proteins

  2. Evaluation of the molluscicidal potential of hydroalcoholic extracts of Jatropha gossypiifolia Linnaeus, 1753 on Biomphalaria glabrata (Say, 1818).

    Science.gov (United States)

    Pereira Filho, Adalberto Alves; França, Clícia Rosane Costa; Oliveira, Dorlam's da Silva; Mendes, Renato Juvino de Aragão; Gonçalves, José de Ribamar Santos; Rosa, Ivone Garros

    2014-01-01

    The action of extracts from the stem, leaves, and fruit of Jatropha gossypiifolia on Biomphalaria glabrata was studied by analyzing survival, feeding capacity and oviposition ability. The extracts were obtained by macerating the plant parts in 92% ethanol, which were then evaporated until a dry residue was obtained and phytochemically studied. The molluscicidal activity on B. glabrata was investigated using the procedures recommended by WHO (1965). The amount of food ingested and oviposition were measured during each experiment. The extract of leaves from J. gossypiifolia was shown to be a strong molluscicidal agent, causing 100% mortality of B. glabrata, even in the lowest concentration tested, of 25 ppm. Regarding the fruit extract, there was variation in the mortality, depending on the concentration used (100, 75, 50 and 25 ppm). The snails that were in contact with the fruit extract had significant reduction in feeding and number of embryos in comparison to the control. The stem extract did not present molluscicidal activity nor had any influence on the feeding and oviposition abilities of B. glabrata, in the concentrations tested. In conclusion, the extracts of leaves and fruits of J. gossypiifolia investigated in this work show molluscicidal effect and may be sources of useful compounds for the schistosomiasis control. PMID:25351545

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

    Science.gov (United States)

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

    2003-02-01

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

  4. The subunit structure of the extracellular hemoglobin of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Full text. The hemoglobin of Biomphalaria glabrata was purified to homogeneity by a two step purification protocol using a gel filtration column (Superose 6 HR/Pharmacia ) followed by an anion exchange chromatography (MONO-Q Sepharose/Pharmacia). The dissociation products were analysed by a 5 - 15 % Polyacrylamide gel electrophoresis containing Sodium Dodecyl Sulfate (SDS-PAGE) giving a band of 270 K Daltons and a band of 180 K Daltons after reduction with β-mercaptoethanol. The same profile was obtained in a 3.5 % Agarose gel electrophoresis containing SDS (SDS-AGE) showing additional bands of higher molecular weight. These bands were proposed to be monomers, dimers and trimers and, after reduction in a Bidimensional SDS-AGE, the proposed monomers and dimers were decomposed in two and four bands that were interpreted as 1 - 4 chains. The hemoglobin was digested by four different proteases ( Thrombin, Trypsin, Chymotrypsin and Subtilisin ) showing several equivalent fragments with molecular weights multiples of its minimum molecular weight ( 17.7 K Daltons). The circular dichroism spectrum of the protein showed a characteristic high α-helix content. We proposed that this hemoglobin is a pentamer of approx. 360 K Daltons subunits each formed by two 180 K Daltons chains linked in pairs by disulfide bridges and each of these chains comprises ten Heme binding domains. These data were compared to other Planorbidae extracellular hemoglobins. Up to now, the quaternary structure of this hemoglobin (shape and disposition of the subunits) is unknown. It is intended to elucidate its structure by Small Angle X-Ray Scattering in Brazilian National Laboratory of Synchrotron Light (LNLS). (author)

  5. Repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida Repopulation of breeding habitats of Biomphalaria glabrata after treatment with niclosamide

    OpenAIRE

    Cecília Pereira de Souza; Nelymar Martineli Mendes

    1991-01-01

    Experimentos foram feitos no laboratório e no campo nos anos de 1980 a 1984, objetivando detectar as causas do repovoamento de criadouros de Biomphalaria glabrata após tratamento com niclosamida. Os bioensaios no laboratório mostraram que a suscetibilidade à niclosamida emulsionável de B. glabrata coletada mensalmente em um sistema de valas de irrigação, variou durante o ano. As concentrações letais CL90 foram 0,15 mgl-1 a 0,60 mgl-1, apresentando diferenças significantes estatisticamente (p ...

  6. Dominant lethal effect of gamma radiation of 60Co in Biomphalaria glabrata (SAY, 1818)

    International Nuclear Information System (INIS)

    Germ cell mutations are used in ecotoxicological studies as biomarkers of population effects and indicators of ecological changes. Biomphalaria glabrata, a freshwater mollusk, is a good experimental model for biomonitoring studies due to its biological characteristics and the ecological importance of this invertebrate group. The dominant lethal test was established in B. glabrata for the detection of germ cell mutations. Results with chemical mutagens showed that this system is efficient, specific and sensitive in the evaluation of germ cell mutations induced by reference mutagens. In this work, the dominant lethal effects of gamma radiation of 60Co were studied. A preliminary experiment was done to establish the dose range and to estimate the chronology of spermatogenesis in B. glabrata. This estimate is possible because of the uniformity in response to ionizing radiation between germ cells at homologous stages of spermatogenesis in widely different species. In general, pre-meiotic germ cells are less sensitive to the induction of lethal dominant mutations than post-meiotic cells. This effect can be attributed to: young gametogenic cells - mitotically active - have greater repair ability from sub-lethal DNA damage and there is a selective elimination of the damaged cells. In our system: induction of lethal dominant mutations causes an increase in the frequency of malformations and, cytotoxic effect is displayed as a reduction in the crossing rates. Total duration of spermatogenesis was estimated in approximately 36 days, with the following distribution of stages: 1 to 13 days - spermatogonia, 14 to 20 days - spermatocytes, 21 to 36 days - spermatids and spermatozoa. Based on this chronology, irradiated wild-type snails with 2,5; 10 and 20Gy and crossed with non-irradiated albino snails after 7, 17, 23, 30 and 36 days. The frequencies of malformations in the heterozygous wild-type offspring of the nonirradiated albino snails were used as indicator of germ cell

  7. Profile of organic acid concentrations in the digestive gland and hemolymph of Biomphalaria glabrata under estivation

    Directory of Open Access Journals (Sweden)

    José Clecildo Barreto Bezerra

    1999-11-01

    Full Text Available Using high performance liquid chromatography (HPLC analysis it was possible to determine simultaneously the concentration of organic acids (pyruvate, lactate, succinate, fumarate, malate, acetate, propionate, acetoacetate, and ß-hydroxybutyrate in the digestive gland and the extracellular concentration of these same acids in the hemolymph of estivating Biomphalaria glabrata, the intermediate host of Schistosoma mansoni. After a 7 day period of estivation, there was a significant increase in the tissue levels of lactate, succinate, malate and acetate compared to non-estivating snails. After 14 days of estivation, the levels of lactate and acetate were also significantly elevated. The hemolymph concentrations of pyruvate and acetate increased significantly after 7 days and acetate concentrations continued to be significantly increased up to 14 days of estivation. The other organic acids studied, such as ketone body acetoacetate and ß-hydroxybutyrate or the volatile acid propionate, did not accumulate. Their tissue concentrations, however, increased on the 7th day of estivation and reached normal levels within two weeks of estivation for some of them. One should take into consideration how the reduction in metabolism can be handled under aerobic conditions, and what role anaerobic pathways may play in both energy formation and redox balance processes.

  8. Evaluation of the mitochondrial system in the gonad-digestive gland complex of Biomphalaria glabrata (Mollusca, Gastropoda) after infection by Echinostoma paraensei (Trematoda, Echinostomatidae).

    Science.gov (United States)

    Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Santos, Anderson Teixeira; Garcia, Juberlan da Silva; Maldonado, Arnaldo; da-Silva, Wagner Seixas; Rodrigues, Maria de Lurdes de Azevedo; Pinheiro, Jairo

    2016-05-01

    The effect of infection by Echinostoma paraensei on the mitochondrial physiology of Biomphalaria glabrata was investigated after exposure to 50 miracidia. The snails were dissected one, two, three and four weeks after infection for collection and mechanical permeabilization of the gonad-digestive gland (DGG) complex. The results obtained indicate that prepatent infection by this echinostomatid fluke significantly suppresses the phosphorylation state (respiratory state 3) and basal oxygen consumption of B. glabrata, demonstrating that the infection reduces the ability of the intermediate host to carry out aerobic oxidative reactions. Additionally, relevant variations related to the uncoupled mitochondrial (state 3u) of B. glabrata infected by E. paraensei were observed. Four weeks after exposure, a significant reduction in mitochondrial oxygen consumption after addition of ADP (3.68±0.26pmol O2/mg proteins) was observed in the infected snails in comparison with the respective control group (5.14±0.25). In the uncoupled state, the infected snails consumed about 62% less oxygen than the infected snails (7.87±0.84pmol O2/mg proteins) in the same period. These results demonstrate a reduction in oxidative decarboxylation rate of the tricarboxylic acid cycle and faster anaerobic degradation of carbohydrates in the infected snails. The possible mechanisms that explain this new metabolic condition in the infected organisms are discussed. PMID:27079167

  9. Comparative toxicity of Euphorbia milii latex and synthetic molluscicides to Biomphalaria glabrata embryos.

    Science.gov (United States)

    Oliveira-Filho, Eduardo C; Geraldino, Barbara R; Coelho, Deise R; De-Carvalho, Rosângela R; Paumgartten, Francisco J R

    2010-09-01

    Plant molluscicides have been regarded as possible alternatives to the costly and environmentally hazardous molluscicides currently available. This study was undertaken to compare the developmental toxicity of a plant molluscicide (Euphorbia milii latex, LAT) with that of three synthetic molluscicidal compounds. Biomphalaria glabrata egg masses (0-15 h after spawning) were exposed to molluscicides for 96 h and thereafter examined up to the 14th day after spawning. Embryo deaths, abnormal embryo development (malformations) and the day of hatching were recorded. Although exhibiting a weak ovicidal effect, LAT markedly impaired the development of snail embryos at concentrations 1000 microg L(-1) and produced anomalies (EC(50)=2040 microg L(-1)) such as abnormal shells, hydropic embryos, cephalic and non-specific malformations. Embryolethal potencies of molluscicides were as follows: triphenyltin hydroxide (TPTH; LC(50)=0.30 microg L(-1))>niclosamide (NCL; LC(50)=70 microg L(-1))>copper sulphate (CuSO(4); LC(50)=2190 microg L(-1)) > LAT (LC(50)=34030 microg L(-1)). A few malformations were recorded in embryos exposed to concentrations of TPTH within the range of lethal concentrations, while almost no anomalies were noted among those treated with NCL or CuSO(4). A hatching delay (hatching on day 10 after spawning or later) was observed among LAT-exposed embryos. The effects of NCL, TPTH and CuSO4 on hatching were to some extent masked by their marked embryolethality. The no-observed effect concentrations (NOEC) for embryotoxicity were as follows: TPTH, 0.1 microg L(-1); NCL, 25.0 microg L(-1); CuSO(4), 500.0 microg L(-1) and LAT, 500.0 microg L(-1). Results from this study suggest that, although LAT was not acutely embryolethal after a short-term exposure, it markedly disrupted snail development. The marked embryotoxicity of E. milii possibly contributes to its effectiveness as a molluscicide. PMID:20594574

  10. Differences in the gene expression profiles of haemocytes from schistosome-susceptible and -resistant biomphalaria glabrata exposed to Schistosoma mansoni excretory-secretory products.

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    Zahida Zahoor

    Full Text Available During its life cycle, the helminth parasite Schistosoma mansoni uses the freshwater snail Biomphalaria glabrata as an intermediate host to reproduce asexually generating cercariae for infection of the human definitive host. Following invasion of the snail, the parasite develops from a miracidium to a mother sporocyst and releases excretory-secretory products (ESPs that likely influence the outcome of host infection. To better understand molecular interactions between these ESPs and the host snail defence system, we determined gene expression profiles of haemocytes from S. mansoni-resistant or -susceptible strains of B. glabrata exposed in vitro to S. mansoni ESPs (20 μg/ml for 1 h, using a 5K B. glabrata cDNA microarray. Ninety-eight genes were found differentially expressed between haemocytes from the two snail strains, 57 resistant specific and 41 susceptible specific, 60 of which had no known homologue in GenBank. Known differentially expressed resistant-snail genes included the nuclear factor kappa B subunit Relish, elongation factor 1α, 40S ribosomal protein S9, and matrilin; known susceptible-snail specific genes included cathepsins D and L, and theromacin. Comparative analysis with other gene expression studies revealed 38 of the 98 identified genes to be uniquely differentially expressed in haemocytes in the presence of ESPs, thus identifying for the first time schistosome ESPs as important molecules that influence global snail host-defence cell gene expression profiles. Such immunomodulation may benefit the schistosome, enabling its survival and successful development in the snail host.

  11. Atividade moluscicida do extrato butílico de Phytolaca dodecandra (Endod) sobre Biomphalaria glabrata Molluscicide activity of a buthanol extract of Phytolacca dodecandra (Endod) on Biomphalaria glabrata

    OpenAIRE

    Cecília Pereira de Souza; Nelimar Martinelli Mendes; Neusa Araújo; Naftale Katz

    1987-01-01

    O extrato butílico da Phytolacca dodecandra (tipo 44) obtido de frutos procedentes da Etiópia, foi testado como moluscicida em nosso laboratório e no campo. As concentrações letais, CL90, com 24 horas de exposição, para Biomphalaria glabrata adulta, recém-eclodidas e desovadas foram de 4,5, 23,0 e 102,0 ppm, respectivamente. Para peixes, Lebistes reticulatus, a CL90 foi de 2,0 ppm. Esses resultados foram semelhantes aos obtidos por Lemma em 1984, na Etiópia. Em dois criadouros com água parada...

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

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    Kirk Ruth S

    2009-04-01

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

  13. Morphological characterization of the hemocytes of the pulmonate snail Biomphalaria tenagophila

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    Margherita Anna Barracco

    1993-03-01

    Full Text Available The blood cells of the pulmonate snail Biomphalaria tenagophila, an important transmiter of the trematode Schistosoma mansoni in Brazil, were examined by ligth and transmission electron microscopy (TEM. Two hemocyte types were identified: hyalinocytes and granulocytes. Hyalinocytes are small young (immature, poorly spreading cells, which have a high nucleocytoplasmic ratio and are especially rich in free ribosomes. They do not appear to contain lysosome-like bodies and represent less than 10% of the circulating hemocytes. Granulocytes are larger hemocytes which readily spread on glass surface and which strongly react to the Gomori substrate, indicating the enzyme acid phosphatase usually found in lysosomes. Ultra-structurally, they contain a well-developed rough endoplasmic reticulum, dictyosomes and some some lysosome-like dense bodies. Granulocytes do not exhibit a characteristic granular aspect and the few granules observed in the cytoplasm should correspond to a lysosome system. They were named granulocytes instead of amoebocytes to use the same terminology adopted for Biomphalaria glabrata in order to make easier comparative studies. This is a preface study for more specific investigations on the functional activities of the blood cells of B. tenagophila and their interactions with the trematode parasite.

  14. Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages

    OpenAIRE

    Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko

    2013-01-01

    Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. M...

  15. 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...

  16. Effects of CO-60 gamma radiation on the embryonary development of Biomphalaria Glabrata (Say, 1818)

    International Nuclear Information System (INIS)

    Some aspects of the effects of the ionizing radiation on the embryo and on the genetical material of Biomphalaria glabrata (Mollusca: Gastropoda) are presented. The embryos weresubmitted at various stages of development to doses of 5,10,15,20 and 25 Gy of Co-60 gamma radiation. As a criteia of evaluation of the embryos radiosensitivity, four biological parameters were used: mortality, malformation, hatching and chromossomal aberrations. (M.A.C.)

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

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    Celina M. Modena

    1993-02-01

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

  18. A Comparative Study of the Organic Acid Content of the Hemolymph of Schistosoma mansoni-Resistant and Susceptible Strains of Biomphalaria glabrata

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    José Clecildo Barreto Bezerra

    1997-05-01

    Full Text Available The freshwater snail Biomphalaria glabrata is an intermediate host of the trematode Schistosoma mansoni. However, some strains of B. glabrata are resistant to successful infection by S. mansoni larvae. The present work examines the profile of organic acids present in S. mansoni-resistant and -susceptible strains of B. glabrata, in order to determine whether the type of organic acid present is related to susceptibility. The organic acids were extracted from the hemolymph of two susceptible B. glabrata strains (PR, Puerto Rico and Ba, Jacobina-Bahia from Brazil, and from the resistant strains 13-16-R1 and 10R2, using solid phase extraction procedures followed by high performance liquid chromatography. The organic acids obtained were analyzed and identified by comparison with known standards. Pyruvate, lactate, succinate, malate, fumarate, acetate, propionate, ß-hydroxybutyrate and acetoacetate were detected in all hemolymph samples. Under standard conditions, the concentration of each of these substances varied among the strains tested and appeared to be specific for each strain. An interesting variation was the low concentration of pyruvate in the hemolymph of PR-snails. Only the concentration of fumarate was consistently different (p£ 0.05 between resistant and susceptible strains

  19. Evaluation of radiosensitivity hemocytes of Biomphalaria glabrata exposed to gamma radiation; Avaliacao da radiossensibilidade de hemocitos de Biomphalaria glabrata expostos a radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Silva, L.R.S.; Amaral, A.J., E-mail: luannaribeiro_lua@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife-PE (Brazil). Dept. de Energia Nuclear; Silva, E.B. [Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academico de Vitoria; Amancio, F.F.; Melo, A.M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    2013-06-15

    The mollusc Biomphalaria glabrata have characteristics that allow them to be identified as an animal model ideal for monitoring areas exposed to chemical agents and physical. This study evaluated the effect of ionizing radiation from Cobalt-60 in haemocytes present in the hemolymph of Biomphalaria glabrata, with the goal of using these cells as indicators of the presence of radiation in aquatic environments. The mollusks were divided into five groups: one control and four subjected doses of 25, 35, 45 and 55 Gy of gamma radiation. After 48 hours of irradiation, the clam hemolymph was collected and slides were prepared and stained with Giemsa for analyses under a light microscope. Statistical analysis was performed using ANOVA and Tukey's test, p <0.05. The results showed that the total number of cells after irradiation reduced compared to control except at a dose of 55 Gy. During data analysis, morphological changes were observed in haemocytes of mollusks subjected to doses of 35, 45 and 55 Gy. These modifications consisted of nucleus bilobulated and nucleo plasmatic bridges. Another change was exclusively observed in the cellular exposure of 55 Gy, where hemocytes showed misshapen nuclei and cytoplasm vacuolisation, suggestive of apoptosis. It is concluded that hemocytes are sensitive to radiation and can be used as indicators of the presence of high doses of ionizing radiation in aquatic environments. (author)

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

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    Cecília Pereira de Souza

    1994-12-01

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

  1. Estratégia competitiva entre Biomphalaria glabrata e Biomphalaria tenagophila: estudos de laboratório

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    Mairy Barbosa Loureiro dos Santos

    1989-01-01

    Full Text Available Observation about conhabitation among B. glabrata and B. tenagophila revealed a greater vulnerability of B. tenagophila population during the process of competition when its density was severaly decreased in 12 trials, moderate in 2 trials. It was higher than B. glabrata in only one trial. Some snail water chemical parameters analysed such as pH, alkalinity, conductivity and oxygen dissolve, an the viability rate of batch of eggs didn't give subsidy to explain the competition mechanism. The newly-born survival, in the situation of cohabitation, was low for both species. This reveals the existence of intra and interspecific competitive interacition. The fertility rate reduction of B. tenagophila during the cohabitation was considered as a cause of its exlusion. One of the factors that seems to have influenced the fertility rate was a possible wrong crossing.

  2. Effects of 60Co gamma radiation on Biomphalaria glabrata (Say, 1818) Embryo, I. Mortality

    International Nuclear Information System (INIS)

    A study was conducted on the radiosensitivity of Biomphalaria glabrata embryos submitted to doses of 5, 10,15,20 and 25 Gy of 60Co during the cleavage, blastula, gastrula, young trochophore and trochophore stages. Mortality was the parameter used to evaluated the damage induced by ionizing radiation. Susceptibility decreased with increasing embryo age and with decreased radiation dose. Estimated LD50 values (15 days) showed that the cleavage stage (4.3 Gy) was approximately four times more radiosensitive than the trochophore stage (17.0 Gy). The survival curves obtained for each embryo stage are discussed on the basis of the multitarget theory. (author)

  3. Comparative study of the fecundity and fertility of Biomphalaria glabrata (Say, 1818 and Biomphalaria straminea (Dunker, 1848 in a laboratory through self-fertilization and cross-fertilization Estudo comparativo da fecundidade e fertilidade de Biomphalaria glabrata (Say, 1818 e Biomphalaria straminea (Dunker, 1848 em laboratório por autofecundação e fecundação cruzada

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    Marta Julia F.S. Costa

    2004-06-01

    Full Text Available The aim of this study was to compare the fecundity and fertility of B. glabrata and B. straminea by cross- and self-fertilization. To attain this objective, laboratory-raised strains of B. glabrata and B. straminea were used. The former originated from natural breeding grounds in the municipality Paulista, state of Pernambuco, Brazil. The latter originated from irrigation ditches in the municipality of Petrolândia, in the same state. Snail populations of B. glabrata and B. straminea were maintained for 240 days in laboratory. Their fecundity was evaluated by noting the number of egg-masses, eggs and eggs per mass. Their fertility was evaluated by the number of viable eggs and the hatching rate. B. straminea was markedly more fecund than B. glabrata through cross- and self-fertilization, namely: greater egg-mass; higher egg production and more eggs per mass. Regarding fertility, there seemed to be no preferential period for occlusion to occur or a trend in the rhythm of producing viable eggs.O objetivo deste trabalho foi comparar a fecundidade e fertilidade de Biomphalaria glabrata e Biomphalaria straminea em condições de laboratório considerando a autofecundação e a fecundação cruzada. Durante oito meses, foram registrados em laboratório, o número de cápsulas ovíferas (desovas, ovos por cápsula ovífera, ovos totais, taxa de eclosão e percentual de ovos férteis dos moluscos criados individualmente e agrupados. Foram utilizados exemplares de B. glabrata de Paulista, PE e B. straminea oriunda de Petrolândia, PE. As observações foram divididas por faixa etária no periódo de 0 a 240 dias. Os resultados obtidos neste trabalho mostram que B. straminea apresenta um potencial reprodutivo maior do que B. glabrata, tanto para moluscos criados em grupo quanto para os criados individualmentes. A comparação dos valores encontrados para fecundidade dentro da mesma espécie sugere que a autofecundação como estratégia reprodutiva,

  4. The significance of the amoebocyte-producing organ in Biomphalaria glabrata

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    Samaly dos Santos Souza

    2012-08-01

    Full Text Available In molluscs, internal defence against microorganisms is performed by a single cell type, i.e., the haemocyte or amoebocyte. The origin of these cells in Biomphalaria glabrata was initially thought to be localised within the vasculo-connective tissue. More recently, origin from a single organ, termed the amoebocyte-producing organ (APO, has been postulated based on the occurrence of hyperplasia and mitoses during Schistosoma mansoni infection. The present investigation represents a histological, immuno-histochemical and ultra-structural study of the B. glabrata APO, whereby histological identification was facilitated by means of collecting epithelial basophilic cells. These cells were comprised of single-cell layers that cover a portion of the stroma, which contains many small, round cells and haemolymph sinuses, as well as a small area of the pericardial surface of the reno-pericardial region. On occasion, this epithelial component vaguely resembled the vertebrate juxtaglomerular apparatus, which reinforces its presumed relationship to the kidney. Both in normal and infected molluscs, mitoses were only occasionally found. The present quantitative studies failed to demonstrate the presence of APO cellular hyperplasia, either in normal or schistosome-infected B. glabrata. Conversely, several structural details from the APO region in B. glabrata were found to be consistent with the hypothesis that the APO is a filtration organ, i.e., it is more closely related to the kidney rather than the bone marrow, as has been suggested in the literature.

  5. Rheotaxis of Biomphalaria glabrata on vertical substrates and its role in the recolonization of habitats treated with molluscicides

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    P. Jurberg

    1988-06-01

    Full Text Available The authors observed specimens of Biomphalaria glabrata climbing up the vertical wall of a ditch against the current. The snails that showed this behavior during application of a molluscicide in the breeding site survived and probably played a role in repopulation, which was observed three months later. These observations motivated field and laboratory investigations which led the authors to conclude that: a this species is able to climb vertical surfaces both in field and laboratory situations; b the current of water, as a physical stimulus, is sufficient to trigger this behavior (rheotaxis; c rheotaxis on vertical surfaces depends on the presence of a necessarily moderate current; d there are indications that B. glabrata may undergo habituation with respect to rheotaxis on vertical walls, e the relationship between rheotaxis and habituation should be considered as a factor causing snail grouping in water bodies which may contribute to their localization in the field; f rheotaxis on vertical surfaces may facilitate population dispersal, and its occurrence should be considered when campaigns for the control of schistosomiasis transmission are planned. The authors present some proposals to avoid the manifestation of this behavior in some filed situations.Os autores observaram exemplares de Biomphalaria glabrata subindo contra corrente em uma parede vertical de uma vala, constatando que os caramujos que apresentavam esse comportamento durante a aplicação de miluscicida neste criadouro sobreviveram e, provavelmente, tiveram papel de repovoamento, que foi observado três meses após. Essas observações suscitaram investigações de campo e de laboratório, através das quais concluiram que: a esta espécie é capaz de subir em superfícies verticais em situações de campo e de laboratório; b a corrente da água enquanto estímulo físico, é suficiente para desencadear esse comportamento (reotaxia; c a reotaxia em superfícies verticais depende

  6. Evaluation of radiosensitivity hemocytes of Biomphalaria glabrata exposed to gamma radiation

    International Nuclear Information System (INIS)

    The mollusc Biomphalaria glabrata have characteristics that allow them to be identified as an animal model ideal for monitoring areas exposed to chemical agents and physical. This study evaluated the effect of ionizing radiation from Cobalt-60 in haemocytes present in the hemolymph of Biomphalaria glabrata, with the goal of using these cells as indicators of the presence of radiation in aquatic environments. The mollusks were divided into five groups: one control and four subjected doses of 25, 35, 45 and 55 Gy of gamma radiation. After 48 hours of irradiation, the clam hemolymph was collected and slides were prepared and stained with Giemsa for analyses under a light microscope. Statistical analysis was performed using ANOVA and Tukey's test, p <0.05. The results showed that the total number of cells after irradiation reduced compared to control except at a dose of 55 Gy. During data analysis, morphological changes were observed in haemocytes of mollusks subjected to doses of 35, 45 and 55 Gy. These modifications consisted of nucleus bilobulated and nucleo plasmatic bridges. Another change was exclusively observed in the cellular exposure of 55 Gy, where hemocytes showed misshapen nuclei and cytoplasm vacuolisation, suggestive of apoptosis. It is concluded that hemocytes are sensitive to radiation and can be used as indicators of the presence of high doses of ionizing radiation in aquatic environments. (author)

  7. Nonhemocyte sources of selected lysosomal enzymes in Biomphalaria glabrata, B. tenagophila and B. straminea (Mollusca: Pulmonata

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    Gary E. Rodrick

    1981-09-01

    Full Text Available The specific activities of acid phosphatase, alkaline phosphatase, β-glucuronidase, lysozymes, glutamate-oxalacetate transaminase and glutamate-pyruvate transaminate were determined in the head-foot and digestive gland of Brazilian Biomphalaria glabrata (Touros, B. tenagophila (Caçapava and B. straminea (Monsenhor Gil. All six enzymes were detected inthe 3000g supernatant. Both cytoplasmic enzymes, glutamate-oxalacetate and glutamate-pyruvate transaminase exhibited the highest specific activities. In the case of the four hydrolytic enzymes assayed, β-glucuronidase exhibited the highest specific activity while lysozyme showed the lowest activity. All six enzymes are thought to be produced by cells within the head-foot and digestive gland of B. glabrata, B. tenagophila and B. straminea.Foram determinadas, na massa cefalopedal e na glândula digestiva de Biomphalaria glabrata de Touros (Rio Grande do Norte B. tenagophila de Cacapava (Sao Paulo e B. straminea de Monsenhor Gil (Piauí, as atividades específicas das seguintes enzimas: fosfatase acida, fosfatase alcalina, beta-glucuronidase, lisozima, transaminase glutâmico-oxalacetica e transaminase glutâmico-piruvica. As seis enzimas referidas foram detectadas no sobrenadante a 3000g. Ambas as enzimas citoplasmaticas - transaminases glutamico-oxalacetica e glutamico-piruvica - mostraram as atividades específicas mais altas. No caso das quatro enzimas hidrolíticas, a beta-glucuronidase revelou a mais alta atividade específica, enquanto a lisozima revelou a mais baixa. E admitido que todas as seis enzimas sao produzidas por celulas presentes na massa cefalopedal e na glândula digestiva das tres especies de moluscos examinadas.

  8. The role of behavior in the survival of Biomphalaria glabrata in biossays with the plant molluscicide Phytolacca dodecandra O papel do comportamento na sobrevivência de Biomphalaria glabrata submetida a bioensaios com o moluscicida vegetal Phytolacca dodecandra

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    P. Jurberg

    1988-03-01

    Full Text Available This work examines the role of behavior in the survival of Biomphalaria glabrata exposed to 25, 50 75 and 100 mgl-1 of Phytolacca dodecandra. Time-lapse cinematography was used to quantify accurately the following parameters: (a frequency of exits from the solution, (b time spent out of the solution and (c time elapsed until the first exit from the solution. These behavior patterns were statistically compared between surviving snails and those which later died. The proportion of surviving snails leaving the liquid medium was significantly higher than that of dying snails. In addition, the surviving group spent significantly more time out of the solution than the group which died, except for the 100 mgl-1 concentration. However, no significant difference was detected in the time elapsed until the first exit from the solution. It can be concluded that both the tendency to leave the P. dodecandra solutions, and the time spent out of them, contributed significantly to snail survival. Molluscicide bioassays should take into account the possibility that some behavior patterns of planorbids might contribute to the protection of the snails.Este trabalho investiga o papel do comportamento na sobrevivência de Biomphalaria glabarta exposta a 25, 50, 75 e 100 mgI-1 de Phytolacca dodecandra. Foi utilizada a técnica de cinematografia com lapso de tempo para quantificar acuradamente os seguintes parâmetros (a freqüência de saídas da solução, (b tempo de permanência fora da solução e (e tempo decorrido até a primeira saída da soluçao. Estes padrões comportamentais foram estatisticamente comparados no que se refere aos caramujos sobreviventes e aos que vieram a morrer. Dentre os camundongos que abandonaram o meio líquido, a proporção de sobreviventes foi significativamente maior que a de mortos. Além disso, um tempo significativamente maior de permanência fora da solução foi observado no grupo que sobreviveu, em relação ao grupo que veio

  9. Effects of Co60 gamma radiation on Biomphalaria glabrata (Say, 1818) Embryo. II. Malformations

    International Nuclear Information System (INIS)

    The morphogenetic effects of ionizing radiation were investigated in Biomphalaria glabrata embryos irradiated in the cleavage, blastula, gastrula, young trochophore and trochophore stages with 5 to 25 Gy doses of 60CO gamma radiation. The number of malformed embryos rapidly increased with increasing radiation dose, reaching a maximum between 5th to 8th day after irradiation in all stages analyzed. Susceptibility to malformation induction was higher the younger than the age of the irradiated embryo. However, for the cleavage stage the frequency of malformed embryos was inversely proportional to radiation dose for the same radiation dose. Several types of morphogenetic malformations were obtained, among then cephalic malformations, exogastrula, shell malformations and embryos with everted stomodeum, unspecific malformations being the most frequent. The results show that the types of malformation induced by radiation probably are not radiation-specific and do not depend on the dose applied

  10. 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...

  11. Effect of Niclosamide (Bayluscide WP 70 (R, Anacardium occidentale hexane extract and Euphorbia splendens latex on behavior of Biomphalaria glabrata (Say, 1818, under laboratory conditions

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    Pedro Jurberg

    1995-04-01

    Full Text Available The repellent effect of the molluscicides Niclosamide (Bayluscide WP 70 (R, Anacardium occidentale and the latex of Euphorbia splendens on Biomphalaria glabrata was observed through the investigation of the occurrence of escape behavior among molluscs that were exposed to dosages lower than the LD 50. The total number of individuals out of water among the surviving snails in the control group provided a "Natural Escape Index". The comparison between this total and the total number of surviving snails in each group exposed to the different dosages of the molluscicides after 24 hr provided the "Molluscicide Escape Index" and the detection of a "Repellency Range" to these snails. The escape indexes for Niclosamide, A. occidentale and E. splendens were 10, 6.22 and 6.44 respectively. Repellency occurred at the following concentration ranges: 0.01, 0.02 and 0.03 ppm Bayluscide, 0.1, 0.2 and 0.3 ppm A. occidentale and 0.05, 0.10, 0.15 and 0.20 ppm E. splendens. The Natural Escape Index obtained in the control group was zero.

  12. Schistosomiasis control using piplartine against Biomphalaria glabrata at different developmental stages.

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    Ludmila Nakamura Rapado

    Full Text Available BACKGROUND: Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. METHODS AND FINDINGS: The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems. The compounds responsible for the molluscicidal activity were identified using (1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml and the fish Danio rerio (1.69 µg/ml. The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. CONCLUSIONS: The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio. Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to

  13. Schistosomiasis Control Using Piplartine against Biomphalaria glabrata at Different Developmental Stages

    Science.gov (United States)

    Rapado, Ludmila Nakamura; Pinheiro, Alessandro de Sá; Lopes, Priscila Orechio de Moraes Victor; Fokoue, Harold Hilarion; Scotti, Marcus Tullius; Marques, Joaquim Vogt; Ohlweiler, Fernanda Pires; Borrely, Sueli Ivone; Pereira, Carlos Alberto de Bragança; Kato, Massuo Jorge; Nakano, Eliana; Yamaguchi, Lydia Fumiko

    2013-01-01

    Background Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active. Methods and Findings The molluscicidal activity of P. tuberculatum was monitored on methanolic extracts from different organs (roots, leaves, fruit and stems). The compounds responsible for the molluscicidal activity were identified using 1H NMR and ESIMS data and multivariate analyses, including principal component analysis and partial least squares. These results indicated that the high molluscicidal activity displayed by root extracts (LC50 20.28 µg/ml) was due to the presence of piplartine, a well-known biologically-active amide. Piplartine was isolated from P. tuberculatum root extracts, and the molluscicidal activity of this compound on adults and embryos of B. glabrata was determined. The compound displayed potent activity against all developmental stages of B. glabrata. Next, the environmental toxicity of piplartine was evaluated using the microcrustacean Daphnia similis (LC50 7.32 µg/ml) and the fish Danio rerio (1.69 µg/ml). The toxicity to these organisms was less compared with the toxicity of niclosamide, a commercial molluscicide. Conclusions The development of a new, natural molluscicide is highly desirable, particularly because the commercially available molluscicide niclosamide is highly toxic to some organisms in the environment (LC50 0.25 µg/ml to D. similis and 0.12 µg/ml to D. rerio). Thus, piplartine is a potential candidate for a natural molluscicide that has been extracted from a tropical plant species and showed less toxic to environment. PMID

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

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    Luiz Candido de Souza Dias

    1987-08-01

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

  15. Malacological survey of Biomphalaria snails in municipalities along the Estrada Real in the southeast of the State of Minas Gerais, Brazil

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    Sandra Helena Cerrato Tibiriçá

    2011-04-01

    Full Text Available INTRODUCTION: The increasing practice of ecotourism and rural tourism in the State of Minas Gerais, Brazil, highlights the importance of studies concerning the occurrence of potential intermediate hosts of Schistosoma mansoni. This study aimed to identify species of Biomphalaria snails in municipalities along the Estrada Real, an important Brazilian tourism project. METHODS: The specimens were collected in different water collections of 36 municipalities along the Estrada Real in the southeast of the State of Minas Gerais. Biomphalaria species were characterized using both morphological and molecular approaches. The research was conducted between August 2005 and September 2009 and all the sites visited were georeferenced using GPS. RESULTS: Six Biomphalaria species were found in 30 of the 36 municipalities studied: glabrata, tenagophila, straminea, peregrina, occidentalis and schrammi. The first three species of Biomphalaria, recognized as intermediate hosts of S. mansoni, were present in 33.3%, 47.2% and 8.3% of the municipalities studied, respectively. The mollusks were found in different types of water collections and no infection by S. mansoni was detected. The highest occurrence of Biomphalaria concentration was verified in the area covered by the Caminho Novo route (Diamantina/MG to Rio de Janeiro/RJ. CONCLUSIONS: Considering the occurrence of schistosomiasis in the State of Minas Gerais and the socioeconomic repercussions involved in the Estrada Real Project, this work focuses on the vulnerability of water collections due to the presence of Biomphalaria mollusks and emphasizes the need for epidemiological surveillance and sanitary and educational measures integrated with the local community and tourism sectors.

  16. Measurement of Selected Enzymatic Activities in Solanum nigrum-Treated Biomphalaria arabica Snails

    Science.gov (United States)

    Al-Daihan, Sooad

    In the present study, glucose, acid and alkaline phosphatases (ACP and ALP), α-amylase and lipase were measured for the first time in tissue homogenates of Biomphalaria arabica snails, molluscan intermediate host for Schistosoma mansoni in Saudi Arabia. Also, the effect of sublethal concentrations (LC25) of dry powdered Solanum nigrum leaf was tested as plant molluscicide against this snail species. The tested enzymes were altered in molluscicide-treated snails compared to control. While ALP and amylase were slightly affected, ACP and lipase were significantly altered. Glucose as an important energy source for a successful schistosome-snail relationship was significantly reduced in molluscicide-treated snails. In conclusion, sublethal concentration of the molluscicide showed potent effect in disturbing snail biochemistry which may render them physiologically unsuitable for the developing of schistosome parasite. This could be considered as a promising strategy to control the disease.

  17. Controlled chaos of polymorphic mucins in a metazoan parasite (Schistosoma mansoni) interacting with its invertebrate host (Biomphalaria glabrata).

    OpenAIRE

    Emmanuel Roger; Christoph Grunau; Pierce, Raymond J.; Hirohisa Hirai; Benjamin Gourbal; Richard Galinier; Rémi Emans; Cesari, Italo M.; Céline Cosseau; Guillaume Mitta

    2008-01-01

    International audience Invertebrates were long thought to possess only a simple, effective and hence non-adaptive defence system against microbial and parasitic attacks. However, recent studies have shown that invertebrate immunity also relies on immune receptors that diversify (e.g. in echinoderms, insects and mollusks (Biomphalaria glabrata)). Apparently, individual or population-based polymorphism-generating mechanisms exists that permit the survival of invertebrate species exposed to p...

  18. Seleção genética de Biomphalaria glabrata e Biomphalaria tenagophila visando a alteração da suscetibilidade e resistência ao Schistosoma mansoni Genetic selection of Biomphalaria glabrata and Biomphalaria tenagophila seeking the alteration of the susceptibility and resistance to the Schistosoma mansoni

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    Nádia Regina Borim Zuim

    2005-10-01

    Full Text Available Gerações de Biomphalaria glabrata e Biomphalaria tenagophila selecionadas geneticamente para resistência e suscetibilidade ao Schistosoma mansoni das linhagens BH e SJ foram utilizadas no estudo da adaptação do trematódeo ao hospedeiro intermediário. As gerações dos planorbídeos foram obtidas por autofecundação dos moluscos que se apresentaram suscetíveis ou resistentes após a exposição aos miracídios de Schistosoma mansoni. Para Biomphalaria glabrata foram obtidas as gerações: Parental, F1S (Suscetível, F1R (Resistente, F2S e F2R. Para a Biomphalaria tenagophila foram estudadas as gerações: Parental, F1S, F1R e F50S. A comparação das taxas de infecção apresentadas pelas diferentes gerações mostrou que, em ambas as espécies, o aumento da suscetibilidade foi mais facilmente obtido do que o aumento da resistência. A dificuldade em aumentar a resistência do molusco ao S. mansoni tem fortes implicações epidemiológicas.Generations of Biomphalaria glabrata and Biomphalaria tenagophila selected genetically for resistance and susceptibility to Schistosoma mansoni of strains BH and SJ were used in a study of the trematode adaptation to the intermediate host. Descendants of the planorbids were obtained by self-fertilization of the mollusks that became susceptible or resistant after exposure to the miracidia of Schistosoma mansoni. For Biomphalaria glabrata they were obtained from the following generations: Parental, F1S (Susceptible, F1R (Resistant, F2S and F2R. For Biomphalaria tenagophila the studied generations were: Parental, F1S, F1R and F50S. The comparison of the infection rates presented by the different generations showed that the increase in susceptibility was more easily obtained in both species. The difficulty in increasing the resistance of the mollusks to Schistosoma mansoni has important epidemiologic implications.

  19. Influence of gamma radiation on the levels of polyphenols and lethality of ethanol extracts of Anacardium occidentale Linn., against Biomphalaria glabrata; Influencia da radiacao gama na acao moluscicida de extratos de cajueiro em Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Santos, G.H.F.; Silva, E.B., E-mail: santosghf@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Radioprotecao e Radioecologia; Melo, A.M.M.A.; Lima, C.S.A [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica; Amorim, E.L.C.; Peixoto Sobrinho, T.J.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Farmacia

    2013-08-15

    Plant materials rich in phenolic compounds, such as Anacardium occidentale Linn., Have been used as alternatives to synthetic pesticides in Biomphalaria glabrata control programs, intermediate host of Schistosoma mansoni. Studies show that ionizing radiation can influence the content of phenolic compounds and thus their biological actions. The aim of this study was to evaluate the influence of gamma radiation of {sup 60}Co in polyphenol composition of hydroalcoholic extracts of bark and leaves of A. occidentale and evaluate the toxicity of these extracts to embryos and adults of B. glabrata. To achieve this goal this, the extracts were irradiated at 10 kGy, the controls being maintained from 0 kGy and positive (CaCO{sub 3}) and negative (H{sub 2}O). We quantified the total phenols by the Folin-Ciocalteau and tannins by precipitation of casein. Extracts were used at a concentration of 100 mg/L. The results showed that the radiation caused the changes to the leaves, the percentage of polyphenols and tannins, and the percentage of lethality in embryos and adults Biomphalaria glabrata, these percentages being: 13 ± 5 (0 kGy) and 27 ± 2.5 (10 kGy), and 36.67 ± 5.77 (0 kGy), and 56.67 ± 5.77 (10 kGy), respectively. Gamma radiation caused significant changes in the levels of polyphenols in the extracts of leaves of Anacardium ocidentale Linn., translated by the increased toxicity of this extract against embryos and adults of Biomphalaria glabrata. This indicates that gamma radiation can be used as an agent potentiating the toxicity of plant extracts on the alternate use of these materials as molluscicides. (author)

  20. Aspectos físico-químicos e biológicos relacionados à ocorrência de Biomphalaria glabrata em focos litorâneos da esquistossomose em Pernambuco

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    Silva Petronildo Bezerra da

    2006-01-01

    Full Text Available This study analyzes the physico-chemical and biological parameters of freshwater aquatic environments in coastal areas of the State of Pernambuco, Brazil, where snail vector foci and cases of schistosomiasis have been recorded. The tests were carried out using standard methods and sediments were analyzed using the X-ray fluorescence technique. The micro-algae were analyzed using conventional microscopy. The most abundant chemical elements in the sediments were Fe, Ca, Si and Al and there were high concentrations of electrolytes in comparison with data published in the literature. The mean values for salinity (7.7 g/L and sulfate (489 mg/L were much higher than normal for freshwater environments. The micro-algae identified are those that inhabit environments with higher levels of salinity. The snail Biomphalaria glabrata seems, therefore, to be more tolerant to salty environments and this constitutes a risk of spread of schistosomiasis.

  1. Aspectos físico-químicos e biológicos relacionados à ocorrência de Biomphalaria glabrata em focos litorâneos da esquistossomose em Pernambuco

    Directory of Open Access Journals (Sweden)

    Petronildo Bezerra da Silva

    2006-10-01

    Full Text Available This study analyzes the physico-chemical and biological parameters of freshwater aquatic environments in coastal areas of the State of Pernambuco, Brazil, where snail vector foci and cases of schistosomiasis have been recorded. The tests were carried out using standard methods and sediments were analyzed using the X-ray fluorescence technique. The micro-algae were analyzed using conventional microscopy. The most abundant chemical elements in the sediments were Fe, Ca, Si and Al and there were high concentrations of electrolytes in comparison with data published in the literature. The mean values for salinity (7.7 g/L and sulfate (489 mg/L were much higher than normal for freshwater environments. The micro-algae identified are those that inhabit environments with higher levels of salinity. The snail Biomphalaria glabrata seems, therefore, to be more tolerant to salty environments and this constitutes a risk of spread of schistosomiasis.

  2. Larvicidal Activity against Aedes aegypti and Molluscicidal Activity against Biomphalaria glabrata of Brazilian Marine Algae

    Science.gov (United States)

    Guedes, Elíca Amara Cecília; de Carvalho, Cenira M.; Ribeiro Junior, Karlos Antonio Lisboa; Lisboa Ribeiro, Thyago Fernando; de Barros, Lurdiana Dayse; de Lima, Maria Raquel Ferreira; Prado Moura, Flávia de Barros; Goulart Sant'Ana, Antônio Euzebio

    2014-01-01

    This study investigated the biological activities of five benthic marine algae collected from Northeastern Region of Brazil. The tested activities included larvicidal activity against Aedes aegypti, molluscicidal activity against Biomphalaria glabrata, and toxicity against Artemia salina. Extracts of Ulva lactuca (Chlorophyta), Padina gymnospora, Sargassum vulgare (Phaeophyta), Hypnea musciformis, and Digenea simplex (Rhodophyta) were prepared using different solvents of increasing polarity, including dichloromethane, methanol, ethanol, and water. Of the extracts screened, the dichloromethane extracts of H. musciformis and P. gymnospora exhibited the highest activities and were subjected to bioassay-guided fractionation in hexane and chloroform. The chloroform fractions of the P. gymnospora and H. musciformis extracts showed molluscicidal activity at values below 40 μg·mL−1 (11.1460 μg·mL−1 and 25.8689 μg·mL−1, resp.), and the chloroform and hexane fractions of P. gymnospora showed larvicidal activity at values below 40 μg·mL−1 (29.018 μg·mL−1 and 17.230 μg·mL−1, resp.). The crude extracts were not toxic to A. salina, whereas the chloroform and hexane fractions of P. gymnospora (788.277 μg·mL−1 and 706.990 μg·mL−1) showed moderate toxicity, indicating that the toxic compounds present in these algae are nonpolar. PMID:24688787

  3. The effect of gamma radiation and caffeine during the embrionic development of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Some experiments have been carried out, dealing with the interations of caffeine and gamma radiation in the embryonic development of Biomphalaria glabrata. Gamma radiation was used in a dosis of 1000r (exposure time of 1/2 hour) and caffeine concentration was 0.1% (Exposure time of 24 hours). Experiment I. The embryos were irradiated before treatment with caffeine. In this experiment we have observed a synergistic effect between caffeine and gamma radiation. Experiment II. The embryos in the caffeine solution were irradiated 8 hours after the beginning of the experiment. The synergistic effect observed in this experiment was reduced when compared with the first one. Experiment III. In this experiment we made the pre-treatment with caffeine. We have not observed any synergistic effect between the drug and gamma radiation. Experiment IV. Embryos were irradiated, and after 24 hours treated with caffeine during another 24 hours. As in the previous experiment, we have not observed any synergism between the radiation and the drug. According to the above results, we conclude that the synergistic effect between caffeine and gamma radiation in the embryos was more effective when the embryos have been treated with caffeine after irradiation. (Author)

  4. Aspectos histológicos das gônadas hermafroditas de Biomphalaria glabrata e Bradybaena similaris (Mollusca, Gastropoda, Pulmonata

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    Rinaldo Florêncio da Silva

    2009-01-01

    Full Text Available Biomphalaria glabrata (Say, 1818 é um gastrópode pulmonado de água doce que desperta grande interesse médico e veterinário. Bradybaena similaris (Férussac, 1821 é um gastrópode pulmonado terrestre considerado uma praga agrícola de plantações de hortaliças. Ambas as espécies são hospedeiras intermediárias de helmintos. Esses moluscos possuem uma gônada hermafrodita produtora de óvulos e espermatozóides de forma simultânea. Neste estudo foram avaliados aspectos histomorfológicos das gônadas hermafroditas de B. glabrata e B. similaris. A gônada de B. similaris encontra-se subdividida em lobos com glândulas em seu interior, o que não foi observado em B. glabrata. Além disso, em B. similaris as células germinativas estão acumuladas em determinados pontos e com a presença de um ovócito em cada folículo da gônada; não obstante, em B. glabrata as células germinativas encontraram-se justapostas e com mais de um ovócito em cada folículo.Biomphalaria glabrata (Say, 1818 is a freshwater pulmonate gastropod that represents great medical importance. Bradybaena similaris (Férussac, 1821 is a terrestrial pulmonate gastropod and an important plague to the different plant cultures with economic interest. Both species are intermediate hosts of helminths. These molluscs have hermaphrodites gonads producing eggs and sperm. Here, we examined histoformological aspects of hermaphrodites gonads of both B. glabrata and B. similaris. The gonad of B. similaris is subdivided into lobes and presence of glands in its interior, which was not observed in B. glabrata. Moreover, in B. similaris the germ cells are accumulated in some areas, and has one oocyte in each follicle in the gonad; however, in B. glabrata the germ cells are juxtaposed and more than one oocyte in each follicle.

  5. Molluscicide activity of the "Avelós" plant (Euphorbia tirucalli, L. ) on Biomphalaria glabrata, the mollusc vector of schistosomiasis

    OpenAIRE

    Pedro Jurberg; Januário Bispo Cabral Neto; Virgínia T. Schall

    1985-01-01

    An aqueous solution of the latex of Euphorbia tirucalli collected at sites receiving large amounts of sunlight showed molluscicide action on Biomphalaria glabrata, with LD50 obtained at the concentration of 28,0 ppm and LD90 at the concentration of 85,0 ppm. The toxicity of the product for fish was similar to that of Bayluscide and of copper sulfate used for comparison. However, the wide distribution of the plant, its easy propagation and the simple procedure for extraction of the active subs...

  6. Atividade moluscicida de extratos e de aucubina de Vitex gardneriana Schauer (Verbenaceae) em embriões da Biomphalaria glabrata

    OpenAIRE

    Lira de Sá Barreto, Lívia Cristina; Carvalho, Elaine Farías Neves de Barros; Soares da Cunha Filho, Marcílio Sérgio; Pereira Ferreira, Clébio; Xavier, Haroudo Satiro

    2007-01-01

    Estudo fitoquímico das folhas, cascas do caule e das raízes de Vitex gardneriana Schauer (Verbenaceae) revelaram a presença de terpenóides/esteróides, saponinas, açúcares redutores, fenilpropanoglicosídeos e iridóides. Os extratos oriundos das folhas e das cascas do caule apresentaram maior quantidade de metabólitos secundários e foram eleitos, junto com o iridóide aucubina, para ensaio moluscicida frente a desovas de Biomphalaria glabrata, hospedeiro intermediário da esquistossom...

  7. Comportamento de Biomphalaria glabrata (Say, 1818 como critério de toxicidade em ensaios biológicos com moluscicidas Behavior of Biomphalaria glabrata (Say, 1818 as a parameter of toxicity in biological assays with molluscicides

    Directory of Open Access Journals (Sweden)

    Otávio S. Pieri

    1981-06-01

    Full Text Available Visando à aplicação sistemática de parâmetros comportamentais como indicadores da ação tóxica de moluscicidas empregados no combate aos hospedeiros intermediários do Schistosoma mansoni, um procedimento para avaliação quantitativa do efeito de dose sobre o comprotamento de Biomphalaria glabrata foi desenvolvido, com base no paradigma recomendado pela O.M.S. para ensaios biológicos e envolvendo registro comportamental por cenematografia ocm lapso de tempo: caramujos com 5 7/8 ± 1/8 giros eram subemtidos a diferentes concentrações subletais de sulfato de cobre durante 24 horas e em seguida transferidos para recuperação em água destilada desionizada; a partir da análise dos registros foram computados (a a freqüência total de subidas à superfície por indivíduo, (b a frqüência total de saídas da água por indivíduo e (c a proporção média de indivíduos no terço superior do recipiente de teste. O método Litchfield-Wilcoxon foi empregaod para determinação de índices de referência (denominados "concentrações de efieto comportamental de 50%" ou CEC50 em relação a cada parâmetro, e os valores obtidos - (a 0,010, (b 0,006 e (c 0,029 ppm de cobre - não só evidenciaram a exeqüibilidade da aplicação sistemática de critérios comportamentais de toxidade, como se revelaram capazes de detectar o efieto tóxico do produto em concentrações muito infereiores às obtidas nas determinações convencionais de letalidade. Os dados também mostraram alterações na atividade dos caramujos em decorrência do ciclo de iluminação dia-noite. Embora o esclarecimento dos aspectos etológicos envolvidos no problema do controle químico do vetor dependa da análise das relações entre o indivíduo e seu ambiente natural, estudos de laboratório com mensurações acuradas de parâmetros relacionados a comportamentos de proteção podem fornecer subsídios relevantes a respeito.The possibility of using reliable behavioural

  8. Molluscicide activity of the "Avelós" plant (Euphorbia tirucalli, L. on Biomphalaria glabrata, the mollusc vector of schistosomiasis

    Directory of Open Access Journals (Sweden)

    Pedro Jurberg

    1985-12-01

    Full Text Available An aqueous solution of the latex of Euphorbia tirucalli collected at sites receiving large amounts of sunlight showed molluscicide action on Biomphalaria glabrata, with LD50 obtained at the concentration of 28,0 ppm and LD90 at the concentration of 85,0 ppm. The toxicity of the product for fish was similar to that of Bayluscide and of copper sulfate used for comparison. However, the wide distribution of the plant, its easy propagation and the simple procedure for extraction of the active substance, which is biodegradable, favor "avelós" as a promising agent in the control of schistosomiasis.Uma solução aquosa de Euphorbia tirucalli (avelós coletada em locais ensolarados mostrou atividade moluscicida para Biomphalaria glabrata obtendo-se a LD50 a uma concentração de 28,0 ppm e a LD90 a 85,0 ppm. A toxicidade do produto para peixes foi similar a de Bayluscide e sulfato de cobre testados comparativamente. Pela larga distribuição da planta e sua fácil propagação e extração da substância ativa, e pela ausência de efeito residual, a planta pode ser considerada como promissora para testes de campo em locais restritos.

  9. Radioprotective effect of the extract of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata submitted to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Williams N.; Silva, Luanna R.S.; Silva, Edvane B. [Universidade Federal de Pernambuco (DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Lacerda, Laila B.N.; Silva, Hianna A.M.F.; Santos, Mariana L.O.; Sa, Jose L.F.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Electromagnetic radiations are energies that can be classified as non-ionizing and ionizing. This type of energy is propagated by a material medium and the vacuum. The important characteristic of ionizing radiation is the localized release of large amounts of energy. The biological effects of radiation result principally from damage to DNA, which is the critical target. Given these harmful effects caused by radiation highlights the importance of acquiring knowledge about the radioprotective substance, because they act to protect the living tissue, decreasing the damage he caused by the effects of radiation. In this study we investigated the radioprotective effect of extract hydroalcoholic of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata. The embryos of Biomphalaria glabrata pigmented were divided into 18 groups of 100 specimens. The experimental groups were exposed to the extracts at a concentration of 200 ppm and then irradiated. For irradiation, we used a source of {sup 60}Co (Gammacell of Radionics Labs. Dose rate = 4.359 Gy/h). The viability of the embryos was examined using a stereoscopic microscope and statistical analysis was performed using the test Student-Newman-Keuls and {chi}{sup 2}. Our results showed that the extracts of hydroalcoholic Ziziphus joazeiro showed radioprotective effect and that the aqueous extract of the bark of Anacardium occidentale exhibited a reduction in its embryotoxic effect. (author)

  10. Radioprotective effect of the extract of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata submitted to ionizing radiation

    International Nuclear Information System (INIS)

    Electromagnetic radiations are energies that can be classified as non-ionizing and ionizing. This type of energy is propagated by a material medium and the vacuum. The important characteristic of ionizing radiation is the localized release of large amounts of energy. The biological effects of radiation result principally from damage to DNA, which is the critical target. Given these harmful effects caused by radiation highlights the importance of acquiring knowledge about the radioprotective substance, because they act to protect the living tissue, decreasing the damage he caused by the effects of radiation. In this study we investigated the radioprotective effect of extract hydroalcoholic of Ziziphus joazeiro and Anacardium occidentale on embryos of Biomphalaria glabrata. The embryos of Biomphalaria glabrata pigmented were divided into 18 groups of 100 specimens. The experimental groups were exposed to the extracts at a concentration of 200 ppm and then irradiated. For irradiation, we used a source of 60Co (Gammacell of Radionics Labs. Dose rate = 4.359 Gy/h). The viability of the embryos was examined using a stereoscopic microscope and statistical analysis was performed using the test Student-Newman-Keuls and χ2. Our results showed that the extracts of hydroalcoholic Ziziphus joazeiro showed radioprotective effect and that the aqueous extract of the bark of Anacardium occidentale exhibited a reduction in its embryotoxic effect. (author)

  11. Analysis of toxicity of Anacardium occidentale L. extract submitted to ionizing radiation on embryos of Biomphalaria glabrata and Artemia salina

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Hianna A.M.F.; Sa, Jose L.F.; Lima, Claudia S.A.; Amancio, Francisco F.; Melo, Ana M.M.A., E-mail: hiannaamfs@gmail.com, E-mail: luismuma6@gmail.com, E-mail: claudia.salima@gmail.com, E-mail: amancioff@bol.com.br, E-mail: amdemelo@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Biofisica e Radiobiologia; Ribeiro, Luanna R.S.; Santos, Gustavo H.F.; Silva, Edvane B., E-mail: luannaribeiro_lua@hotmail.com, E-mail: santosghf@hotmail.com, E-mail: edvborges@yahoo.com.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia

    2013-07-01

    The use of gamma radiation as a sterilization method for herbs, herbal medicines and foods, shows positive results regarding the retention of such products, economy and safety of the method. However, it is known that this method of processing plant material can cause chemical changes in these products related to the type of material, its components and the dose received. Evaluated, in the present study, the action of gamma radiation as a modifier of toxicity extract of Anacardium occidentale Linn. To evaluate the toxicity of the extract irradiated at doses of 5.0, 7.5 and 10.0 kGy and concentrations of 250, 500 and 1000 mg/L was used bioassays with Artemia salina and Biomphalaria glabrata. For the test to A. salina, 520 specimens were used divided into groups of 10 larvae. For the bioassay with B. glabrata, 3900 specimens were used divided into groups of, approximately, 100 embryos. Larvae of A. salina and embryos were subjected to extracts irradiated and unirradiated for 24 hours. The bioassay with A. salina, showed a decrease, compared to extract unirradiated and irradiated at doses of 5.0 and 7.5 kGy, of extract irradiated with 10 kGy, where the mortality did not differ from the control group. In tests with embryos was observed an increase in the toxicity of the extract at a dose of 7.5 kGy and a decrease in the dose of 10.0 kGy. The radiation promoted changes in the toxicity of leaves extracts of Anacardium occidentale Linn. on embryos of Biomphalaria glabrata and Artemia salina. (author)

  12. Analysis of toxicity of Anacardium occidentale L. extract submitted to ionizing radiation on embryos of Biomphalaria glabrata and Artemia salina

    International Nuclear Information System (INIS)

    The use of gamma radiation as a sterilization method for herbs, herbal medicines and foods, shows positive results regarding the retention of such products, economy and safety of the method. However, it is known that this method of processing plant material can cause chemical changes in these products related to the type of material, its components and the dose received. Evaluated, in the present study, the action of gamma radiation as a modifier of toxicity extract of Anacardium occidentale Linn. To evaluate the toxicity of the extract irradiated at doses of 5.0, 7.5 and 10.0 kGy and concentrations of 250, 500 and 1000 mg/L was used bioassays with Artemia salina and Biomphalaria glabrata. For the test to A. salina, 520 specimens were used divided into groups of 10 larvae. For the bioassay with B. glabrata, 3900 specimens were used divided into groups of, approximately, 100 embryos. Larvae of A. salina and embryos were subjected to extracts irradiated and unirradiated for 24 hours. The bioassay with A. salina, showed a decrease, compared to extract unirradiated and irradiated at doses of 5.0 and 7.5 kGy, of extract irradiated with 10 kGy, where the mortality did not differ from the control group. In tests with embryos was observed an increase in the toxicity of the extract at a dose of 7.5 kGy and a decrease in the dose of 10.0 kGy. The radiation promoted changes in the toxicity of leaves extracts of Anacardium occidentale Linn. on embryos of Biomphalaria glabrata and Artemia salina. (author)

  13. Ecotoxicological effect of sublethal exposure to zinc oxide nanoparticles on freshwater snail Biomphalaria alexandrina.

    Science.gov (United States)

    Fahmy, Sohair R; Abdel-Ghaffar, Fathy; Bakry, Fayez A; Sayed, Dawlat A

    2014-08-01

    Freshwater snails are used as sensitive biomarkers of aquatic ecosystem pollution. The potential impacts of zinc oxide nanoparticles (ZnONPs) on aquatic ecosystems have attracted special attention due to their unique properties. The present investigation was designed to evaluate the possible mechanisms of ecotoxicological effects of ZnONPs on freshwater snail Biomphalaria alexandrina. ZnONPs showed molluscicidal activity against B. alexandrina snails, and the LC50 was 145 μg/ml. Two tested concentrations of ZnONPs were selected: The first concentration was equivalent to LC10 (7 μg/ml), and the second was equivalent to LC25 (35 μg/ml). Exposure to ZnONPs (7 and 35 μg/ml) for three consecutive weeks significantly induced malondialdehyde and nitric oxide with concomitant decreases in glutathione and glutathione-S-transferase levels in hemolymph and soft tissues of treated snails. Moreover, ZnONPs elicited a significant decrease in total protein and albumin contents coinciding with enhancement of total lipids and cholesterol levels as well as activities of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase in hemolymph and soft tissues of treated snails. This study highlights the potential ecological implications of ZnONP release in aquatic environments and may serve to encourage regulatory agencies in Egypt to more carefully monitor and regulate the industrial use and disposal of ZnONPs. PMID:24736985

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

    Science.gov (United States)

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

    2016-09-01

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

  15. The endocrine disruptor effect of the herbicides atrazine and glyphosate on Biomphalaria alexandrina snails.

    Science.gov (United States)

    Omran, Nahla Elsayed; Salama, Wesam Mohamed

    2016-04-01

    Atrazine (AZ) and glyphosate (GL) are herbicides that are widely applied to cereal crops in Egypt. The present study was designed to investigate the response of the snailBiomphalaria alexandrina(Mollusca: Gastropoda) as a bioindicator for endocrine disrupters in terms of steroid levels (testosterone (T) and 17β-estradiol (E)), alteration of microsomal CYP4501B1-like immunoreactivity, total protein (TP) level, and gonadal structure after exposure to sublethal concentrations of AZ or GL for 3 weeks. In order to study the ability of the snails' recuperation, the exposed snails were subjected to a recovery period for 2 weeks. The results showed that the level of T, E, and TP contents were significantly decreased (p≤ 0.05) in both AZ- and GL-exposed groups compared with control (unexposed) group. The level of microsomal CYP4501B1-like immunoreactivity increased significantly (p≤ 0.05) in GL- and AZ-exposed snails and reach nearly a 50% increase in AZ-exposed group. Histological investigation of the ovotestis showed that AZ and GL caused degenerative changes including azoospermia and oocytes deformation. Interestingly, all the recovered groups did not return back to their normal state. It can be concluded that both herbicides are endocrine disrupters and cause cellular toxicity indicated by the decrease of protein content and the increase in CYP4501B1-like immunoreactivity. This toxicity is irreversible and the snail is not able to recover its normal state. The fluctuation of CYP4501B1 suggests that this vertebrate-like enzyme may be functional also in the snail and may be used as a biomarker for insecticide toxicity. PMID:24215068

  16. Activities of naphthoquinones against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae), vector of dengue and Biomphalaria glabrata (Say, 1818), intermediate host of Schistosoma mansoni

    OpenAIRE

    Ribeiro, Karlos A. L.; Carvalho, Cenira Monteiro de; Molina, María Teresa; Pereira Lima, Estelita; López-Montero, Eulogio; Oliveira, Maria Beatriz Farias de; Ventura Pinto, Antonio; Santana, Antônio Euzébio G.; Goulart, Marília O. F.; Reys, José Rui M.

    2009-01-01

    Larvicidal (against Aedes aegypti Linnaeus, 1762) and molluscicidal (against Biomphalaria glabrata Say,1818) activities of several natural and synthetic naphthoquinoneswere measured, with significant results. The best larvicidal compound is 3-bromojuglone, while the better molluscicides are 2-bromo- and 3- bromo-5-acetoxy-1,4-naphthoquinones together with the 3-bromo-5-methoxy derivative. The present results reinforce the potential use of substituted hydroxyquinones, their salts and hal...

  17. Bases génétiques du polymorphisme de compatibilité dans l'interaction Schistosoma mansoni / Biomphalaria glabrata

    OpenAIRE

    Roger, Emmanuel

    2008-01-01

    The co-evolutionary dynamics that exist in certain invertebrate host / parasite interactions sometimes lead to a compatibility polymorphism, of which the molecular bases are unknown. To identify key molecules involved in this phenomenon in the Schistosoma mansoni / Biomphalaria glabrata model, we developed a comparative proteomics approach for the larval stages that interact with the invertebrate host. The qualitative and quantitative comparison of the proteomes of compatible and incompatible...

  18. Histamine Immunoreactive Elements in the Central and Peripheral Nervous Systems of the Snail, Biomphalaria spp., Intermediate Host for Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Mohamed R Habib

    Full Text Available Histamine appears to be an important transmitter throughout the Animal Kingdom. Gastropods, in particular, have been used in numerous studies establishing potential roles for this biogenic amine in the nervous system and showing its involvement in the generation of diverse behaviours. And yet, the distribution of histamine has only previously been described in a small number of molluscan species. The present study examined the localization of histamine-like immunoreactivity in the central and peripheral nervous systems of pulmonate snails of the genus Biomphalaria. This investigation demonstrates immunoreactive cells throughout the buccal, cerebral, pedal, left parietal and visceral ganglia, indicative of diverse regulatory functions in Biomphalaria. Immunoreactivity was also present in statocyst hair cells, supporting a role for histamine in graviception. In the periphery, dense innervation by immunoreactive fibers was observed in the anterior foot, perioral zone, and other regions of the body wall. This study thus shows that histamine is an abundant transmitter in these snails and its distribution suggest involvement in numerous neural circuits. In addition to providing novel subjects for comparative studies of histaminegic neurons in gastropods, Biomphalaria is also the major intermediate host for the digenetic trematode parasite, which causes human schistosomiasis. The study therefore provides a foundation for understanding potential roles for histamine in interactions between the snail hosts and their trematode parasites.

  19. Influence of gamma radiation on the levels of polyphenols and lethality of ethanol extracts of Anacardium occidentale Linn., against Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Plant materials rich in phenolic compounds, such as Anacardium occidentale Linn., Have been used as alternatives to synthetic pesticides in Biomphalaria glabrata control programs, intermediate host of Schistosoma mansoni. Studies show that ionizing radiation can influence the content of phenolic compounds and thus their biological actions. The aim of this study was to evaluate the influence of gamma radiation of 60Co in polyphenol composition of hydroalcoholic extracts of bark and leaves of A. occidentale and evaluate the toxicity of these extracts to embryos and adults of B. glabrata. To achieve this goal this, the extracts were irradiated at 10 kGy, the controls being maintained from 0 kGy and positive (CaCO3) and negative (H2O). We quantified the total phenols by the Folin-Ciocalteau and tannins by precipitation of casein. Extracts were used at a concentration of 100 mg/L. The results showed that the radiation caused the changes to the leaves, the percentage of polyphenols and tannins, and the percentage of lethality in embryos and adults Biomphalaria glabrata, these percentages being: 13 ± 5 (0 kGy) and 27 ± 2.5 (10 kGy), and 36.67 ± 5.77 (0 kGy), and 56.67 ± 5.77 (10 kGy), respectively. Gamma radiation caused significant changes in the levels of polyphenols in the extracts of leaves of Anacardium ocidentale Linn., translated by the increased toxicity of this extract against embryos and adults of Biomphalaria glabrata. This indicates that gamma radiation can be used as an agent potentiating the toxicity of plant extracts on the alternate use of these materials as molluscicides. (author)

  20. Impact of the age of Biomphalaria alexandrina snails on Schistosoma mansoni transmission: modulation of the genetic outcome and the internal defence system of the snail

    Directory of Open Access Journals (Sweden)

    Iman Fathy Abou-El-Naga

    2015-08-01

    Full Text Available Of the approximately 34 identified Biomphalariaspecies,Biomphalaria alexandrinarepresents the intermediate host of Schistosoma mansoniin Egypt. Using parasitological and SOD1 enzyme assay, this study aimed to elucidate the impact of the age of B. alexandrinasnails on their genetic variability and internal defence against S. mansoniinfection. Susceptible and resistant snails were reared individually for self-reproduction; four subgroups of their progeny were used in experiment. The young susceptible subgroup showed the highest infection rate, the shortest pre-patent period, the highest total cercarial production, the highest mortality rate and the lowest SOD1 activity. Among the young and adult susceptible subgroups, 8% and 26% were found to be resistant, indicating the inheritance of resistance alleles from parents. The adult resistant subgroup, however, contained only resistant snails and showed the highest enzyme activity. The complex interaction between snail age, genetic background and internal defence resulted in great variability in compatibility patterns, with the highest significant difference between young susceptible and adult resistant snails. The results demonstrate that resistance alleles function to a greater degree in adults, with higher SOD1 activity and provide potential implications for Biomphalariacontrol. The identification of the most susceptible snail age enables determination of the best timing for applying molluscicides. Moreover, adult resistant snails could be beneficial in biological snail control.

  1. Correlation between steroid sex hormones, egg laying capacity and cercarial shedding in Biomphalaria alexandrina snails after treatment with Haplophyllum tuberculatum.

    Science.gov (United States)

    Rizk, Maha Z; Metwally, Nadia S; Hamed, Manal A; Mohamed, Azza M

    2012-10-01

    Schistosomiasis is considered the second most pre-valiant worldwide parasitic disease ranked next to malaria. It has significant economic and public health consequences in many developing countries. Several ways have been practiced in order to bring the disease under an adequate control through the breakage of the life cycle of the parasite. Snail control could be regarded as a rapid and efficient of reducing or eliminating transmission and remains among the methods of choice for schistosomiasis control. The aim of this work is to evaluate the role of Haplophyllum tuberculatum (family Rutaceae) as a plant molluscicide. The mortality rate of Biomphalaria alexandrina snails were monitored after treatment with three extracts of the plant aerial parts; petroleum ether, chloroform and ethanol. Chloroform extract that recorded the most potent effect was further evaluated through measuring the toxicity pattern against B. alexandrina snails, egg laying capacity, cercarial shedding, phenol oxidase enzyme and the levels of steroid sex hormones. Histopathological examination of hepatopancreas and ovotestis of treated snails were also done for result confirmation. Treatment of snails by chloroform extract recorded reduction in egg laying capacity, decrease in cercarial shedding, diminution in phenol oxidase enzyme, disturbance in steroid sex hormones and sever alternation of the histopathological picture of snails tissue. In conclusion, H. tuberculatum recorded molluscicidal potency against B. alexandrina snails. Further studies are needed for its environmental applications. PMID:22771439

  2. Paenibacillus, a novel pathogen of Biomphalaria glabrata, an intermediate host for schistosomiasis

    OpenAIRE

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Rognon, Anne; Arancibia, Nathalie; Allienne, Jean-François; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2014-01-01

    Schistosomiasis is the second most widespread tropical parasitic disease after malaria. To achieve the objective of schistosomiasis eradication in a decade, various research strategies and treatment programs were recommended and supported by WHO. One of these applicable approaches is based on the control of snail vectors in endemic area. Previous field studies have shown that competitor or predator introduction could be effective but no systemic investigation has ever been conducted to identi...

  3. Sublethal Effects of Some New Textile Dyes On the Freshwater Snail Biomphalaria alexandrina, as a Biological Indicator

    International Nuclear Information System (INIS)

    The Eco toxicological effects of three synthetic textile dyes; fast violet (FV), fast orange (FO) and fast yellow (FY) which mainly used in textile industry in Egypt, were tested on the freshwater snail Biomphalaria alexandrina, that used as a bio-indicator. The results demonstrated that only the FV dye is lethal and the 72 hr LC 50 is 500 ppm. The FO and dyes did not show any lethal effect on the snails at the concentrations used throughout the experiment time. The sublethal toxic concentration of non-irradiated FV dye (100 ppm) showed an increase in cellular and humoral defense responses of the snails exposed to the dye for 72 hr. Although the profile of the snail's nucleoproteins revealed minor qualitative differences; were quantitative differences differences reflected in the intensity of the separated bands, as well as, the percentage of the protein content. The protein content significantly decreased in the snails exposed to FV-dye when compared to FO,FY and non-exposed control snails

  4. The distribution of Biomphalaria spp. in different habitats in relation to physical, biological, water contact and cognitive factors in a rural area in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Kloos Helmut

    2001-01-01

    Full Text Available A total of 256 sites in 11 habitats were surveyed for Biomphalaria in Melquiades rural area (State of Minas Gerais in August and November 1999 and in March 2000. Of the 1,780 Biomphalaria collected, 1,721 (96.7% were B. glabrata and 59 (3.3% B. straminea. Snails were found in all habitats except in wells, with the largest mean numbers in tanks, seepage ponds and canals, and the smallest numbers in springs, rice fields and fishponds. People's knowledge of the occurrence of Biomphalaria at the collection sites and the presence of Biomphalaria ova were strongly correlated with the occurrence of snails, and distance between houses and collection sites, as well as water velocity were inversely correlated with Biomphalaria occurrence (p < 0.001. The strongest predictor o f Biomphalaria occurrence was the presence of tilapia fish in fishponds. Fourteen Biomphalaria (0.8% of all snails found at 6 sites were infected with Schistosoma mansoni. Suggestions are made for the utilization of local people's knowledge in snail surveys and further studies are recommended on the possible use of tilapia for biological control of Biomphalaria in fishponds, as well as modeling of S. mansoni transmission and reinfection.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non-sy...

  6. Comparative Study of the Molluscicidal Activity of Some Plant Extracts on the Snail Vector of Schistosoma mansoni, Biomphalaria alexandrina

    Directory of Open Access Journals (Sweden)

    M. Al-Hazmi

    2011-01-01

    Full Text Available Schistosomiasis is considered as one of the most important trematode disease of man. The most important goal of the present study is to use the natural plants as cheaper and available sources for snail control. The present investigation concerned with the evaluation of toxicological, biological and physiological effects of water suspension, cold water and boiled water extracts of Agave filifera whole plant, Ammi majus flowers and leaves and Canna indica flowers and leaves comparing with the effect of different sulphate compounds. The present work revealed that, copper sulphate as well as the water suspension of Ammi majus flowers and leaves disclosed the most potent effect on the cumulative mortality after 6 weeks exposure periods. Also, egg laying capacity and egg hatchability of Biomphalaria alexandrina snails were affected with the exposure to CuSO4 and water suspension of Ammi majus flowers. The sublethal doses (LC10 of copper sulphate and water suspension of the tested plants reduced the total protein and total lipid contents of the hemolymph of B. alexandrina snails. The activity of transaminases enzymes as well as acetylcholinesterase had been affected by the exposure to the sublethal doses of copper sulphate and the water suspension of the tested plants. Also, histopathological changes were recorded in hermaphrodite gland of B. alexandrina snails post 6 weeks of exposure.

  7. Aspectos ultraestruturais de hemócitos de Biomphalaria glabrata Say (1818) (Gastropoda: Planorbidae) analisados sob microscopia eletrônica de transmissão Ultrastructural aspects of hemocytes from Biomphalaria glabrata Say (1818) (Gastropoda: Planorbidae) analysed with transmission eletronic microscopy

    OpenAIRE

    Marco Antonio Vasconcelos Santos; José Antonio Picanço Diniz

    2009-01-01

    Os hemócitos do caramujo Biomphalaria glabrata, um importante transmissor do trematódeo Schistosoma mansoni no Brasil, foram coletados de especimens na região Bragantina, localizada a oeste do estado do Pará. Os hemócitos foram examinados por meio de microscopia eletrônica de transmissão. As células foram fixadas pelo método de rotina com o uso do tampão PHEM (PIPES, HEPES, EGTA e Magnésio). Foram descritos os aspectos ultra-estruturais celulares como inclusões citoplasmáticas limitadas por m...

  8. Biomphalaria alexandrina in Egypt: Past, present and future

    Indian Academy of Sciences (India)

    Iman F Abou-El-Naga

    2013-09-01

    The African species of Biomphalaria appeared as a result of the relatively recent west-to-east trans-Atlantic dispersal of the Biomphalaria glabrata-like taxon. In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. Biomphalaria alexandrina originated in the area between Alexandria and Rosetta and has historically been confined to the Nile Delta. Schistosoma mansoni reached Egypt via infected slaves and baboons from the Land of Punt through migrations that occurred as early as the Vth Dynasty. The suggestion of the presence of Schistosoma mansoni infection in Lower Egypt during Pharaonic times is discussed despite the fact that that there is no evidence of such infection in Egyptian mummies. It is only recently that Biomphalaria alexandrina colonized the Egyptian Nile from the Delta to Lake Nasser. This change was likely due to the construction of huge water projects, the development of new water resources essential for land reclamation projects and the movement of refugees from the Suez Canal zone to the Delta and vice versa. The situation with respect to Biomphalaria in Egypt has become complicated in recent years by the detection of Biomphalaria glabrata and a hybrid between both species; however, follow-up studies have demonstrated the disappearance of such species within Egypt. The National Schistosoma Control Program has made great strides with respect to the eradication of schistosoma; however, there has unfortunately been a reemergence of Schistosoma mansoni resistant to praziquantel. There are numerous factors that may influence the prevalence of snails in Egypt, including the construction of water projects, the increase in reclaimed areas, global climate change and pollution. Thus, continued field studies in addition to the cooperation of several scientists are needed to obtain an accurate representation of the status of this species. In addition, the determination of the genome sequence for Biomphalaria alexandrina and the

  9. Histological and histochemical studies on the effect of gamma-irradiation on the hermaphrodite gland of the freshwater snail biomphalaria Alexandrina

    International Nuclear Information System (INIS)

    The effect of gamma-irradiation on the histological and histochemical changes in the hermaphrodite gland of biomphalaria Alexandrina varies according to the level of radiation exposure. Snails were exposed to gamma-irradiation using a 60Co source at the dose levels 100, 300 and 600 Gy. They were examined on different time periods ranged between 10 to 30 days governed by the survival time of snails. Histological observation indicated that both spermatogenic and orogenic stages within the hermaphrodite gland were variably affected. However, the male stages were more radiosensitive than in the female ones. Partial recovery in the hermaphrodite gland of snails exposed to 100 Gy was only observed 30 days post-irradiation. Histochemical changes of carbohydrate and protein inclusions in hermaphrodite gland of snails treated at the dose levels 100, 300 and 600 Gy showed that these contents were much reduced in the germ cells as compared with those observed in the control ones.18 fig

  10. Neotropical planorbid snails with apertural lamellae: I. Biomphalaria helophila (Orbigny, 1835)

    OpenAIRE

    W. Lobato Paraense

    1996-01-01

    A definition of Biomphalaria helophila (Orbigny, 1835) is presented, based on examination of the shell and reproductive system of topotypic specimens and extended to a number of samples from other localities. The following nominal species and subspecies, collected from type localities, proved junior synonyms of B. helophila: Planorbis albicans Pfeiffer, 1839; Planorbis dentatus Gould, 1844; Planorbis dentiferus CB Adams, 1845; Planorbis dentiferus edentatus CB Adams, 1851; Planorbis dentiens ...

  11. Estudo do crescimento de moluscos pertencentes a populações de Biomphalaria glabrata e B. tenagophila

    Directory of Open Access Journals (Sweden)

    Luiz A. Magalhães

    1969-01-01

    Full Text Available Os autores estudam, comparativamente o crescimento de duas populações de moluscos planorbídeos pertencentes às espécies B. glabrata e B. tenagophila. Concluem que não há diferença significativa entre o crescimento dos caramujos oriundos das populações estudadas.

  12. Neotropical planorbid snails with apertural lamellae: I. Biomphalaria helophila (Orbigny, 1835

    Directory of Open Access Journals (Sweden)

    W Lobato Paraense

    1996-04-01

    Full Text Available A definition of Biomphalaria helophila (Orbigny, 1835 is presented, based on examination of the shell and reproductive system of topotypic specimens and extended to a number of samples from other localities. The following nominal species and subspecies, collected from type localities, proved junior synonyms of B. helophila: Planorbis albicans Pfeiffer, 1839; Planorbis dentatus Gould, 1844; Planorbis dentiferus CB Adams, 1845; Planorbis dentiferus edentatus CB Adams, 1851; Planorbis dentiens Morelet, 1849; Planorbula dentiens edentula Fischer & Crosse, 1880; Planorbis stagnicola Morelet, 1851; and Tropicorbis shimeki FC Baker, 1945. B. helophila was also identified in samples from Costa Rica, Guatemala, Haiti, Dominican Republic, Puerto Rico and Barbados.

  13. Controle biológico de Biomphalaria glabrata (Say, 1818 através de Tilapia nilotica (Hasselquist, 1757, em laboratório (Pulmonata, Planorbidae. Pisces, Cichlidae

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    Roberto Milward de Andrade

    1982-12-01

    Full Text Available O peixe cichdeo Tilapia nilotica (Hasse/quist, 1757 I = Sarotherodon niloticus Linnaeus, 1758 foi capaz de impedir o crescimento de 4 populações de 20 espécimens (14-16 mm de diâmetro de Biomphalaria glabrata (Say, 1818, mantidas em aquários de vidro, durante cinco semanas, em laboratório. No Aquário nº 1 foi introduzido um alevino com 55 mm de comprimento (não computada a nadadeira caudal; no de nº 2, um com 63 mm; no de nº 3, dois alevinos: com 40 e 46 mm, respectivamente; e, finalmente, no de nº 4, três espécimens: com 38,39 e 42 mm, respectivamente. Os peixes destruíram as desovas dos planorbíneos depositadas nas paredes de vidro dos aquários - impedindo, assim, as eclosões e, consequentemente, o aumento das quatro populações em estudo. Reversamente, quando retirados, as populações de planorbíneos cresceram em número. Não obstante, salienta-se a necessidade de investigações de campo, afim de avaliar a atividade predatória daquele ciclídeo em condições naturais.

  14. Effects of Bayluscide WP 70® on the Survival and Water-leaving Behaviour of Biomphalaria straminea, Snail Host of Schistosomiasis in Northeast Brazil

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    Sarquis Otília

    1997-01-01

    Full Text Available The toxic and behavioural effects of niclosamide (Bayluscide WP 70® on Biomphalaria straminea from a highly endemic area of schistosomiasis in northeastern Brazil were investigated through laboratory bioassays. The LD50 and LD90 were 0.114 mg/l and 0.212 mg/l, respectively. Water-leaving behaviour occurred among 14% to 30% of the snails in the presence of sublethal doses of niclosamide and among 16% of the controls. It was concluded that both the relatively low susceptibility to niclosamide and water-leaving behaviour of local B. straminea may be responsible for the recolonization of transmission foci after mollusciciding. It was suggested that recently improved measures of snail control, such as controlled-release formulations of niclosamide and plant molluscicides should be considered in areas where snail control is recommended

  15. Molluscicidal Activity of the Methanol Extract of Callistemon viminalis (Sol. ex Gaertner) G.Don ex Loudon Fruits, Bark and Leaves against Biomphalaria alexandrina Snails

    Science.gov (United States)

    A Gohar, Ahmed; T Maatooq, Galal; R Gadara, Sahar; S Aboelmaaty, Walaa; M El-Shazly, Atef

    2014-01-01

    Methanol extracts of Callistemon viminalis (Sol. Ex Gaertner) G.Don Ex Loudon fruits, bark and leaves were tested for molluscicidal activity. Snails were collected and kept in dechlorinated water under standard condition. Ten adults Biomphalaria Alexandrina, of the same size, were introduced in plastic acquaria for each experiment. The fruits, barks and leaves were extracted with methanol and the methanol extracts were kept for testing as molluscicides. Different extracts proved to have molluscicidal activity against the vector of schistosomiasis, B. alexandrina snails. LC50 values for C. viminalis fruits, bark and leaves were 6.2, 32 and 40 ppm respectively. The C. viminalis fruits extract showed the highest effect against the tested snails. Histopathological studies proved that the site of action of all tested extracts was localized in the digestive system and hermaphrodite gland. PMID:25237345

  16. Alterations in the fatty acid profile, antioxidant enzymes and protein pattern of Biomphalaria alexandrina snails exposed to the pesticides diazinon and profenfos.

    Science.gov (United States)

    Bakry, Fayez A; El-Hommossany, Karem; Abd El-Atti, Mahmoud; Ismail, Somaya M

    2016-04-01

    The use of pesticides is widespread in agricultural activities. These pesticides may contaminate the irrigation and drainage systems during agriculture activities and pests' control and then negatively affect the biotic and a biotic component of the polluted water courses. The present study aimed to evaluate the effect of the pesticides diazinon and profenfos on some biological activities of Biomphalaria alexandrina snails such as fatty acid profile, some antioxidant enzymes (thioredoxin reductase (TrxR), sorbitol dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT) as well as glutathione reductase (GR) and lipid peroxidation (LP)) and protein patterns in snails' tissues exposed for 4 weeks to LC10 of diazinon and profenfos. The results showed that the two pesticides caused considerable reduction in survival rates and egg production of treated snails. Identification of fatty acid composition in snail tissues treated with diazinon and profenfos pesticides was carried out using gas-liquid chromatography (GLC). The results declared alteration in fatty acid profile, fluctuation in percentage of long chain and short chain fatty acid contributions either saturated or unsaturated ones, and a decrease in total lipid content in tissues of snails treated with these pesticides. The data demonstrate that there was a significant inhibition in the activities of tissues SOD, CAT, glutathione reductase (GR), TrxR, and SDH in tissues of treated snails, while a significant elevation was detected in LP as compared to the normal control. On the other hand, the electrophoretic pattern of total protein showed differences in number and molecular weights of protein bands due to the treatment of snails. It was concluded that the residues of diazinon and profenfos pesticides in aquatic environments have toxic effects onB. alexandrina snails. PMID:24215063

  17. Glycotope Sharing between Snail Hemolymph and Larval Schistosomes: Larval Transformation Products Alter Shared Glycan Patterns of Plasma Proteins

    OpenAIRE

    YOSHINO, TIMOTHY P.; Wu, Xiao-Jun; Liu, Hongdi; Gonzalez, Laura A.; Deelder, André M; Cornelis H Hokke

    2012-01-01

    Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans) shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivi...

  18. Esquistossomose: nova ocorrência de Biomphalaria straminea em Belo Horizonte, Minas Gerais Schistosomiasis: new occurrence of Biomphalaria straminea in Belo Horizonte, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1996-12-01

    Full Text Available Em Belo Horizonte, Minas Gerais, Brasil, a Biomphalaria straminea é encontrada na região da Pampulha. Recentemente, o molusco foi encontrado em valas da antiga Barragem de Santa Lúcia, foco extinto de esquistossomose transmitida por B. glabrata. Os moluscos foram coletados e examinados para verificar se estavam naturalmente infectados com Schistosoma mansoni. Os exemplares negativos foram usados para criação ou infecção com a cepa LE de S. mansoni, mantida no laboratório, e outra cepa VGS, obtida de ovos de fezes de escolar de Belo Horizonte. Dentre 1.890 moluscos capturados em 1994 e 1995, nenhum estava infectado com S. mansoni. Dentre 87 exemplares coletados no criadouro e expostos à cepa LE, nove (10,3% eliminaram cercárias; dentre 83 moluscos da F1, dez (12,0% eliminaram cercárias e dentre 88 exemplares coletados e expostos à cepa VGS, dez (11,3% eliminaram cercárias. Em Belo Horizonte, a esquistossomose é transmitida por B. glabrata e B. tenagophila. Entretanto, atualmente existe o risco de aparecimento de novo foco, no qual a B. straminea poderá vir a ser a transmissora, se medidas profiláticas adequadas não forem tomadas pelas autoridades responsáveis pela construção de um parque e lago no local.In Belo Horizonte, Minas Gerais, Brazil, the snail Biomphalaria straminea was found in the Pampulha region. Recently the snail was found in ditches in the old Santa Lúcia Reservoir, a now-extinct focus of schistosomiasis transmission by B. glabrata. The snails were collected and examined to verify whether they were naturally infected with Schistosoma mansoni. Negative specimens were used for breeding or infection with the LE strain of S. mansoni from the laboratory and another strain obtained from eggs found in the feces of a schoolchild (VGS from Belo Horizonte. Among the 1890 snails collected from 1994 to 1995, none were infected with S. mansoni. Among 87 snails collected and exposed to the LE strain, 9 (10.3% shed cercariae

  19. Influência do magnésio metálico e diferentes sais de magnésio em desovas de Biomphalaria glabrata (Say, 1818 Influence of metallic magnesium and various magnesium salts on egg-masses of Biomphalaria glabrata (Say, 1818

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1983-12-01

    Full Text Available Soluções de magnésio metálico e diferentes sais de magnésio foram testadas em laboratório, a fim de comprovar a ação das mesmas sobre a oviposição de B. glabrata. Usaram-se, para cada solução, dez caramujos adultos originários da Pampulha, Belo Horizonte-MG (Brasil, criados em laboratório. No experimento I foram estudadas soluções em água desclorada de magnésio elementar (Mg, cloreto de magnésio (MgCl2.6H2O, carbonato de magnésio [(MgCO34.Mg(OH2.nH2O], nitrato de magnésio [Mg(NO32. 6H2O] e sulfato de magnésio (MgSO4.7H2O, e no experimento II, Mg, Mg + latossolo, MgCO3, MgCO3 + latossolo, sempre nas concentrações de 500 e 1.000 ppm. Durante duas semanas os planorbídeos permaneceram em água para adaptação; em seguida, por quatro semanas em exposição com as soluções testadas e, posteriormente, em água por mais duas semanas para recuperação. A cada sete dias as desovas eram contadas, eliminadas e as soluções renovadas. Foi observado que as soluções de Mg e MgCO3, isoladamente ou associada ao latossolo, produziram uma diminuição significativa do número de desovas dos caramujos, mas não parada completa de oviposição, quando comparados os períodos de adaptação com os de exposição. As soluções de Mg e MgCO3 não devem ser consideradas como produtos promissores para o controle da população de B. glabrata, em virtude da diminuição das desovas só terem sido observadas quando foram utilizadas concentrações muito altas.Solutions of magnesium metallic and other salts of magnesium were tested in the laboratory to study the action on B. glabrata oviposition. For each solution, 10 adult snails from Pampulha, Belo Horizonte-MG (Brazil, reared in the laboratory, were used. In experiment I solutions, in dechlorinated water, of magnesium (Mg, magnesium chloride (MgCl2. 6H2O, magnesium carbonate [(MgCO34.Mg(OH2.nH2O], magnesium nitrate [Mg(NO32.6H2O] and magnesium sulfate (MgSO4.7H2O were tested; and in

  20. Avaliação da atividade tóxica em Artemia salina e Biomphalaria glabrata de extratos de quatro espécies do gênero Eleocharis (Cyperaceae

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    A.L.T.G. Ruiz

    2005-06-01

    Full Text Available O gênero Eleocharis R. Br. compreende cerca de 200 espécies, ocorrendo em ambientes úmidos tais como brejos e margens de rios e lagos. Procurando novos agentes moluscicidas, os extratos de Eleocharis acutangula (Roxb. Schult., Eleocharis interstincta (Vahl Roem. & Schult., Eleocharis maculosa (Vahl Roem. & Schult. e Eleocharis sellowiana Kunth foram testados para atividade moluscicida, contra caramujos adultos e desovas, e toxicidade (ensaio de letalidade com Artemia salina. O extrato hexânico de Eleocharis acutangula (parte subterrânea fresca foi ativo contra Artemia salina (CL50 = 476,00 mg/mL, enquanto os demais extratos apresentaram CL50 >> 10³ mg/mL, sugerindo baixa toxicidade. O extrato hidro-etanólico de Eleocharis sellowiana (parte subterrânea fresca foi ativo contra desovas de Biomphalaria glabrata (CL50 = 24,27 mg/mL mas inativo contra indivíduos adultos. Os demais extratos testados não apresentaram atividade moluscicida.

  1. Determinação do período de desenvolvimento e da viabilidade das desovas de duas populações de Biomphalaria glabrata e Biomphalaria tenagophila (Mollusca, Planorbidae

    Directory of Open Access Journals (Sweden)

    L. A. Magalhães

    1971-12-01

    Full Text Available Foram estudadas comparativamente as desovas ãe populações de B. glabrata e B. tenagophila, concluindo-se que nas condições da experiência, houve diferença significativa no que se refere ao período de desenvolvimento dos ovos. Foi verificada que a probabilidade de eclosão com relação ao número de dias de desenvolvimento dos ovos apresentou, em ambas as populações, uma distribuição de Poisson.

  2. Toxicity of Euphorbia milii latex and niclosamide to snails and nontarget aquatic species.

    Science.gov (United States)

    Oliveira-Filho, E C; Paumgartten, F J

    2000-07-01

    The toxicity of Euphorbia milii molluscicidal latex and niclosamide (NCL) to target snails (Biomphalaria glabrata and Biomphalaria tenagophila) and nontarget aquatic organisms is evaluated. Planorbidae snails were killed by very low concentrations of lyophilized latex (48-h LC(50), mg/L: B. glabrata, 0.12; B. tenagophila, 0.09; Helisoma duryi, 0.10). Latex was less toxic (48-h LC(50) or EC(50), mg/L) to oligochaeta (Tubifex tubifex, 0.31), planktonic crustacea (Daphnia similis, 0.38; C. dubia, 1.07; Artemia sp., 0.93), and fishes (Danio rerio, 0.96; Poecilia reticulata, 1. 39), and considerably less toxic to Ampullariidae snails (Pomacea sp. , 10.55) and frog tadpoles (Rana catesbeiana, 7.50). Latex (up to 100 mg/L) was not toxic to bacteria (P. putida and V. fischeri), algae (Selenastrum capricornutum and Chlorella vulgaris), and mosquito larvae (Anopheles albitarsis, Aedes aegypti, Aedes fluviatilis). NCL was very toxic (48-h LC(50) or EC(50), mg/L) to Planorbidae snails (B. glabrata, 0.15, B. tenagophila, 0.13; H. duryi, 0.10), T. tubifex (0.11), crustacea (D. similis, 0.19; Ceriodaphnia dubia, 0.47; Artemia sp. 0.18), fishes (D. rerio, 0.25; P. reticulata, 0.29), R. catesbeiana (0.16), and Pomacea sp. (0.76). NCL was toxic to bacteria, algae (96-h IC(50), mg/L: S. capricornutum, 0.34; C. vulgaris, 1.23) and slightly toxic to mosquito larvae. In conclusion, E. milii latex, as compared with the reference molluscicide niclosamide, presents a higher degree of selectivity toward snails which are intermediate hosts of Schistosoma trematodes. PMID:10903832

  3. Compatibilidad entre nueve cepas de Biomphalaria glabrata de áreas endémicas y no endémicas y una cepa de Schistosoma mansoni venezolanas

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    Pino Luz A.

    1999-01-01

    Full Text Available Se infectaron experimentalmente 9 lotes de 32 caracoles B. glabrata (de 5 a 7mm de diámetro con miracidios de la cepa C5 de Schistosoma mansoni a razón de 5 miracidios por caracol, pertenecientes a las siguientes cepas: En el área endémica de transmisión de Esquistosomiasis mansoni a Sector Puerta Negra, Lago Valencia, b Cagua c Ingenio Bolívar (Estado Aragua d Mariara e Caserío El 25 f Güigüe (Estado Carabobo. Fuera del área endémica de transmisión g Anzoátegui (Estado Lara, h Chabasquén (Estado Portuguesa, i Sector La Elvira, Caripe (Estado Monagas. El período prepatente intramolusco, osciló entre 23 y 25 días, para las 9 cepas evaluadas. La duración total de la infección fue muy variable desde 20 días para la cepa Chabasquén, hasta 93 días para la de Güigüe.La producción total promedio de cercarias al tercer día de iniciada la emisión varió desde X = 74,4 para la cepa de Mariara, hasta X = 591,7 para la cepa de Chabasquén. Se evidenció la existencia de diferencias estadísticamente significativas (H = 97,4, P < 0,05 en la producción total de cercarias al tercer día de iniciada la emisión, detectándose diferencias estadísticamente significativas para casi todas las 36 combinaciones, excepto para las cuatro siguientes: Mariara/Ingenio Bolívar, Cagua/Caserío El 25, Lago de Valencia/Güigüe y Güigüe/Caripe.En lo que respecta al porcentaje de caracoles que presentaron cura espontánea, los valores mas elevados se obtuvieron en las cepas del Lago de Valencia (88,8%, Cagua (85,2%, Chabasquén (82,6%, Caripe (82,6% y Anzoátegui (80%. Mientras que el porcentaje mas bajo se obtuvo para la cepa de Güigüe (21,4%.

  4. Participation of N-acetyl-D-glucosamine carbohydrate moieties in the recognition of Schistosoma mansoni sporocysts by haemocytes of Biomphalaria tenagophila

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    Raquel Lopes Martins-Souza

    2011-11-01

    Full Text Available Lectin-carbohydrate binding may be involved in the recognition of Schistosoma mansoni sporocysts by haemocytes of Biomphalaria; therefore, we tested if this interaction is associated with snail resistance against Schistosoma infection. In vitro data showed that most of the S. mansoni sporocysts cultured with haemocytes from Biomphalaria glabrata BH, a highly susceptible snail strain, had a low number of cells that adhered to their tegument and a low mortality rate. Moreover, the addition of N-acetyl-D-glucosamine (GlcNAc did not alter this pattern of adherence and mortality. Using haemocytes and haemolymph of Biomphalaria tenagophila Cabo Frio, we observed a high percentage of sporocysts with adherent cells, but complete encapsulation was not detected. Low concentrations of GlcNAc increased haemocyte binding to the sporocysts and mortality, which returned to basal levels with high concentrations of the carbohydrate. In contrast, haemocytes plus haemolymph from B. tenagophila Taim encapsulated cellular adhesion index of level 3 and destroyed over 30% of the S. mansoni sporocysts in culture. Interestingly, the addition of GlcNAc, but not mannose, to the culture medium resulted in the significant inhibition of cellular adhesion to the parasite tegument and the reduction of parasite mortality, suggesting that GlcNAc carbohydrate moieties are important to the recognition of S. mansoni by B. tenagophila Taim.

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

    Directory of Open Access Journals (Sweden)

    Delmany Moitinho Barboza

    2012-09-01

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

  6. Influência do magnésio metálico e diferentes sais de magnésio em desovas de Biomphalaria glabrata (Say, 1818) Influence of metallic magnesium and various magnesium salts on egg-masses of Biomphalaria glabrata (Say, 1818)

    OpenAIRE

    Nelymar Martineli Mendes; Naftale Katz

    1983-01-01

    Soluções de magnésio metálico e diferentes sais de magnésio foram testadas em laboratório, a fim de comprovar a ação das mesmas sobre a oviposição de B. glabrata. Usaram-se, para cada solução, dez caramujos adultos originários da Pampulha, Belo Horizonte-MG (Brasil), criados em laboratório. No experimento I foram estudadas soluções em água desclorada de magnésio elementar (Mg), cloreto de magnésio (MgCl2.6H2O), carbonato de magnésio [(MgCO3)4.Mg(OH)2.nH2O], nitrato de magnésio [Mg(NO3)2. 6H2O...

  7. Estudo da potencialidade de populações de Biomphalaria straminea do Estado de Minas Gerais, como hospedeiras do Schistosoma mansoni Potentiality of the Biomphalaria straminea populations of the State of Minas Gerais, as hosts of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1983-09-01

    Full Text Available Caramujos de Biomphalaria straminea, descendentes de exemplares coletados em nove municípios do Estado de Minas Gerais, foram infectados experimentalmente com três cepas de Schistosoma mansoni: "LE", procedente de Belo Horizonte (MG; "SJ", procedente de São José dos Campos (SP e "AL" procedente do Nordeste (AL. As taxas de infeção variaram de 0,0 a 24,0% com a cepa "LE"; de 0,0 a 16% com a cepa "SJ" e de 2,0 a 9,0% com a cepa "AL". Os índices de infecção experimental obtidos foram semelhantes aos registrados por outros autores, para B. straminea dessa região. Comparou-se o número de cercárias de cepa "LE", eliminadas por oito exemplares de B. straminea de Baldim e oito Biomphalaria glabrata do controle, após 30 minutos de exposição à luz. O número de cercárias eliminadas por B. straminea foi de 4.550, aproximadamente cinco vezes menor que o de B. glabrata, 22.679. Discute-se a potencialidade desses moluscos como hospedeiros do S. mansoni nessa região.The decendents of Biomphalaria straminea snails collected in nine regions from the State of Minas Gerais were experimentally infected with three strains of Schistosoma mansoni: "LE", from Belo Horizonte, Minas Gerais; "SJ", from São José dos Campos, State of São Paulo and "AL", from State of Alagoas. The infection rates obtained were of 0 to 24% (LE strain, 0 to 16% (SJ strain and 2 to 9% (AL strain. These infection rates were similar to those obtained by other authors for B. straminea from this region. Comparation were made between the numbers of cercariae (LE strain shed by eight specimens of B. straminea from Baldim and eight B. glabrata of the control group, after 30 minutes of exposure to light. B. straminea shed 4,550 cercariae, about five times less than B. glabrata (22,679. The authors discuss the potentiality of theses molluscs as hosts of S. mansoni in this region.

  8. Susceptibility of Snails to Infection with Schistosomes is influenced by Temperature and Expression of Heat Shock Proteins

    Science.gov (United States)

    Knight, Matty; Elhelu, O; Smith, M; Haugen, B; Miller, A; Raghavan, N; Wellman, C; Cousin, C; Dixon, F; Mann, V; Rinaldi, G; Ittiprasert, W; Brindley, PJ

    2015-01-01

    The freshwater snail, Biomphalaria glabrata is the obligate intermediate host for the transmission of the parasitic trematode, Schistosoma mansoni the causative agent of the chronic debilitating neglected tropical disease, schistosomiasis. We showed previously that in juvenile snails, early and significant induction of stress manifested by the expression of stress proteins, Hsp 70, Hsp 90 and reverse transcriptase (RT) of the non- LTR retrotransposon, nimbus, is a characteristic feature of juvenile susceptible NMRI but not resistant BS-90 snails. These latter, however, could be rendered susceptible after mild heat shock at 32°C, revealing that resistance in the BS-90 resistant snail to schistosomes is a temperature dependent trait. Here we tested the hypothesis that maintenance of BS-90 resistant snails at the permissive temperature for several generations affects the resistance phenotype displayed at the non-permissive temperature of 25°C. The progeny of BS-90 snails bred and maintained through several generations (F1 to F4) at 32°C were susceptible to the schistosome infection when returned to room temperature, shedding cercariae at four weeks post-infection. Moreover, the study of expression levels of the heat shock protein (Hsp) 70 protein by ELISA and western blot analysis, showed that this protein is also differentially expressed between susceptible and resistant snails, with susceptible snails expressing more protein than their resistant counterparts after early exposure to wild-type but not to radiation-attenuated miracidia. These data suggested that in the face of global warming, the ability to sustain a reduction in schistosomiasis by using refractory snails as a strategy to block transmission of the disease might prove challenging since non-lethal elevation in temperature, affects snail susceptibility to S. mansoni. PMID:26504668

  9. Uptake and release of 65Zn and 124Sb by Biomphalaria alexandrina and Cleopatra bulimoides snails and their effects on the ultrastructure of the hermaphrodite gland

    International Nuclear Information System (INIS)

    The freshwater snails, are by far the most prevalent organisms among the local freshwater fauna, and represent an important group of mollusks, from the stand point of health and economy. This is due to he role played by many of them as hosts for certain parasites of man and his animals. These snails are rather considered pests and so their populations are currently controlled by several measures. On the other hand, various radioactive elements are increasingly detected in the aquatic environment, some of them may find their way to the freshwater ecosystems. So it became necessary to find any radiobioindicator from among the common aquatic biota that can be used to detect any radioactive disposal into the freshwater environment. This paper reports a radioactive tracer study on weather the previously mentioned snails can be used either in the biological treatment of low-level radioactive waste and/or as radiobioindicators

  10. 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...

  11. Invading freshwater snails and biological control in Martinique Island, French West Indies

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Pointier

    2001-09-01

    Full Text Available Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp., three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera and one ampullarid (Marisa cornuarietis. Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  12. Glycotope sharing between snail hemolymph and larval schistosomes: larval transformation products alter shared glycan patterns of plasma proteins.

    Science.gov (United States)

    Yoshino, Timothy P; Wu, Xiao-Jun; Liu, Hongdi; Gonzalez, Laura A; Deelder, André M; Hokke, Cornelis H

    2012-01-01

    Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans) shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivity. A panel of monoclonal antibodies (mABs) to specific S. mansoni glycans was used to identify the distribution and abundance of shared glycan epitopes (glycotopes) on plasma glycoproteins from B. glabrata strains that differ in their susceptibilities to infection by S. mansoni. In addition, a major aim of this study was to determine if larval transformation products (LTPs) could bind to plasma proteins, and thereby alter the glycotopes exposed on plasma proteins in a snail strain-specific fashion. Plasma fractions ( 100 kDa) from susceptible (NMRI) and resistant (BS-90) snail strains were subjected to SDS-PAGE and immunoblot analyses using mAB to LacdiNAc (LDN), fucosylated LDN variants, Lewis X and trimannosyl core glycans. Results confirmed a high degree of glycan sharing, with NMRI plasma exhibiting a greater distribution/abundance of LDN, F-LDN and F-LDN-F than BS-90 plasma (LTPs significantly altered the reactivity of specific mABs to shared glycotopes on blots, mainly through the binding of LTPs to plasma proteins resulting in either glycotope blocking or increased glycotope attachment to plasma. Many LTP-mediated changes in shared glycans were snail-strain specific, especially those in the 100 kDa fraction. Our data suggest that differential binding of S. mansoni LTPs to plasma proteins of susceptible and resistant B. glabrata strains may significantly impact early anti-larval immune reactivity, and in turn, compatibility, in this parasite-host system. PMID:22448293

  13. Glycotope sharing between snail hemolymph and larval schistosomes: larval transformation products alter shared glycan patterns of plasma proteins.

    Directory of Open Access Journals (Sweden)

    Timothy P Yoshino

    Full Text Available Recent evidence supports the involvement of inducible, highly diverse lectin-like recognition molecules in snail hemocyte-mediated responses to larval Schistosoma mansoni. Because host lectins likely are involved in initial parasite recognition, we sought to identify specific carbohydrate structures (glycans shared between larval S. mansoni and its host Biomphalaria glabrata to address possible mechanisms of immune avoidance through mimicry of elements associated with the host immunoreactivity. A panel of monoclonal antibodies (mABs to specific S. mansoni glycans was used to identify the distribution and abundance of shared glycan epitopes (glycotopes on plasma glycoproteins from B. glabrata strains that differ in their susceptibilities to infection by S. mansoni. In addition, a major aim of this study was to determine if larval transformation products (LTPs could bind to plasma proteins, and thereby alter the glycotopes exposed on plasma proteins in a snail strain-specific fashion. Plasma fractions ( 100 kDa from susceptible (NMRI and resistant (BS-90 snail strains were subjected to SDS-PAGE and immunoblot analyses using mAB to LacdiNAc (LDN, fucosylated LDN variants, Lewis X and trimannosyl core glycans. Results confirmed a high degree of glycan sharing, with NMRI plasma exhibiting a greater distribution/abundance of LDN, F-LDN and F-LDN-F than BS-90 plasma ( 100 kDa fraction. Our data suggest that differential binding of S. mansoni LTPs to plasma proteins of susceptible and resistant B. glabrata strains may significantly impact early anti-larval immune reactivity, and in turn, compatibility, in this parasite-host system.

  14. Molecular characterisation of intermediate snail hosts and the search for resistance genes

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    David Rollinson

    1998-01-01

    Full Text Available The relationship between schistosomes and their intermediate hosts is an extremely intricate one with strains and species of the parasite depending on particular species of snail, which in turn may vary in their susceptibility to the parasites. In order to gain a better understanding of the epidemiology of the disease we have been investigating the use of molecular markers for snail identification and for studying host-parasite relationships. In this paper we will draw on examples concerning schistosomiasis in West and East Africa to illustrate how a molecular analysis can be used as part of a "total evidence" approach to characterisation of Bulinus species and provide insights into parasite transmission. Particular emphasis is given to ribosomal RNA genes (rRNA, random amplified polymorphic DNA (RAPDs and the mitochondrial gene cytochrome oxidase I (COI. Snails resistant to infection occur naturally and there is a genetic basis for this resistance. In Biomphalaria glabrata resistance to Schistosoma mansoni is known to be a polygenic trait and we have initiated a preliminary search for snail genomic regions linked to, or involved in, resistance by using a RAPD based approach in conjunction with progeny pooling methods. We are currently characterising a variety of STSs (sequence tagged sites associated with resistance. These can be used for local linkage and interval mapping to define genomic regions associated with the resistance trait. The development of such markers into simple dot-blot or specific PCR-based assays may have a direct and practical application for the identification of resistant snails in natural populations.

  15. Identification of Biomphalaria havanensis and Biomphalaria obstructa populations from Cuba using polymerase chain reaction and restriction fragment length polymorphism of the ribosomal RNA intergenic spacer

    Directory of Open Access Journals (Sweden)

    Teofânia HDA Vidigal

    2001-07-01

    Full Text Available In Cuba, several Biomphalaria species have been reported such as B. orbignyi, B. schrammi, B. helophila, B. havanensis and B. peregrina; only the latter three are considered as potential hosts of Schistosoma mansoni. The specific identification of Biomphalaria species is based on anatomical and morphological characters of genital organs and shells. The correct identification of these snails is complicated by the high variation in these characters, similarity among species and in some cases by the small size of the snails. In this paper, we reported the classical morphological identification, the use of PCR and RFLP analysis of the internal transcribed spacer region of the ribosomal RNA genes for molecular identification of seven snail populations from different localities in Cuba. Using morphological and molecular analysis, we showed that among the studied Cuban Biomphalaria populations only B. havanensis and B. obstructa species were found.

  16. Breeding of Biomphalaria tenagophila in mass scale

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    Florence Mara Rosa

    2013-02-01

    Full Text Available An efficient method for breeding Biomphalaria tenagophila (Taim lineage/RS was developed over a 5-year-period (2005-2010. Special facilities were provided which consisted of four cement tanks (9.4 x 0.6 x 0.22 m, with their bottom covered with a layer of sterilized red earth and calcium carbonate. Standard measures were adopted, as follows: each tank should contain an average of 3000 specimens, and would be provided with a daily ration of 35,000 mg complemented with lettuce. A green-house effect heating system was developed which constituted of movable dark canvas covers, which allowed the temperature to be controlled between 20 - 24 ºC. This system was essential, especially during the coldest months of the year. Approximately 27,000 specimens with a diameter of 12 mm or more were produced during a 14-month-period. The mortality rates of the newly-hatched and adult snails were 77% and 37%, respectively. The follow-up of the development system related to 310 specimens of B. tenagophila demonstrated that 70-day-old snails reached an average of 17.0 ± 0.9 mm diameter. The mortality rates and the development performance of B. tenagophila snails can be considered as highly satisfactory, when compared with other results in literature related to works carried out with different species of the genus Biomphalaria, under controlled laboratory conditions.

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

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    Tatiana Maria Teodoro

    2011-11-01

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

  18. 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.

  19. Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites

    Science.gov (United States)

    We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana, Gundlachia radiata Helisoma (= Planorbella) trivolvis, Melanoides tuberculata, Neritina punctulata, and Physa marmorata. Our collections indicate that un-reported species such as Gundlachia radiata and Hel...

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

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    JANNOTTI-PASSOS Liana Konovaloff

    2000-01-01

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

  1. The Pampulha reservoir remains a potential urban focus of schistosomiasis mansoni in Brazil: changes in the occurrence patterns of Biomphalaria species and a new record of the parasite

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    Hudson Alves Pinto

    2013-08-01

    Full Text Available Introduction The Pampulha reservoir has long been a focus of schistosomiasis transmission in Belo Horizonte, State of Minas Gerais, Brazil. The last malacological study conducted in this urban reservoir was more than two decades ago, and thus, an update on the distribution of the species of Biomphalaria as well as new data on the presence of Schistosoma mansoni in this water body are required. Methods The current distribution of Biomphalaria spp. in the Pampulha reservoir and their infection with S. mansoni was evaluated during 55 malacological surveys conducted between 2009 and 2012. Results Biomphalaria straminea displayed a high population density and distribution, and 13.7% (2,233/16,235 of the specimens collected were infected with larval trematodes other than Schistosoma mansoni. Biomphalaria tenagophila and Biomphalaria glabrata, species currently presenting a restricted distribution and small populations, displayed trematode infection rates of 15.2% (98/644 and 13% (83/640, respectively. Thirteen (2% specimens of B. glabrata were found to be infected with S. mansoni. In addition, a historical review based on previous and new data on the occurrence patterns of Biomphalaria species in this reservoir is presented. Conclusions The results indicate that the Pampulha reservoir remains a potential focus of urban schistosomiasis in Brazil, and significant changes in the occurrence patterns of Biomphalaria species were verified.

  2. Fecundity changes induced by low-doses of gamma radiation on Biomphalaria straminea (Dunker, 1848)

    International Nuclear Information System (INIS)

    Biomphalaria straminea, intermediate host of Schistosoma manzoni, are hermaphrodite snails (Paraense and Deslandes 1955, Leal 1976). Widespread in northeast Brazil, and existing in others regions, it contributes to the endemic schistosomiasis occurring in some regions of this country (Paraense and Deslandes 1955). The research on this snail has a social and epidemiological interest for public health (Pessoa and Martins 1982). Previous reports state that the reproductive activity of snails is particularly affected by ionizing radiation (Liard 1968). Aiming to examine more closely some aspects of this subject, this study was performed in order of schistosomiasis after its exposure to low intensity gamma rays, in cross and self fertilization

  3. Differentiation of the sibling species Biomphalaria occidentalis and Biomphalaria tenagophila by the electrophoretic patterns of their hemoglobin

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    James B. Bailey

    1986-09-01

    Full Text Available A simple and rapid method for differentialing the sibling species Biomphalaria tenagophila and Biomphalaria occidentalis by agarose gel electrophoresis (AGE is described. Snail hemolymph is used as the test sample and the red colaration of the hemoglobin fraction permits visualization of the migration patterns without resorting to specific stains. Moreover, hemolymph samples may be obtained without killing the snail, thus permitting its use for other studies for breeding.É descrito um método simples e rápido para distinguir as espécies crípticas Biomphalaria tenagophila e B. occidentalis por eletroforese em gel de agarose. A prova é feita com hemolinfa do molusco, permitindo a cor vermelha da fração hemoglobina visualizar os padrões de migração sem necessidade de recorrer a colorações específicas. Além disso, as amostras de hemolinfa podem ser obtidas sem sacrificar o molusco, que poderá ser usado para outros estudos ou para criação.

  4. Characterization of Biomphalaria orbignyi, Biomphalaria peregrina and Biomphalaria oligoza by polymerase chain reaction and restriction enzyme digestion of the internal transcribed spacer region of the RNA ribosomal gene

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    Spatz Linus

    2000-01-01

    Full Text Available The correct identification of Biomphalaria oligoza, B. orbignyi and B. peregrina species is difficult due to the morphological similarities among them. B. peregrina is widely distributed in South America and is considered a potential intermediate host of Schistosoma mansoni. We have reported the use of the polymerase chain reaction and restriction fragment length polymorphism analysis of the internal transcribed spacer region of the ribosomal DNA for the molecular identification of these snails. The snails were obtained from different localities of Argentina, Brazil and Uruguay. The restriction patterns obtained with MvaI enzyme presented the best profile to identify the three species. The profiles obtained with all enzymes were used to estimate genetic similarities among B. oligoza, B. peregrina and B. orbignyi. This is also the first report of B. orbignyi in Uruguay.

  5. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae) in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    OpenAIRE

    Candia Rowel; Besigye Fred; Martha Betson; Sousa-Figueiredo, Jose C.; Kabatereine, Narcis B.; J. Russell Stothard

    2015-01-01

    This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were cla...

  6. On the Ultrastructure and Function of Rhogocytes from the Pond Snail Lymnaea stagnalis.

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    Maria Kokkinopoulou

    Full Text Available Rhogocytes, also termed "pore cells", occur as solitary or clustered cells in the connective tissue of gastropod molluscs. Rhogocytes possess an enveloping lamina of extracellular matrix and enigmatic extracellular lacunae bridged by cytoplasmic bars that form 20 nm diaphragmatic slits likely to act as a molecular sieve. Recent papers highlight the embryogenesis and ultrastructure of these cells, and their role in heavy metal detoxification. Rhogocytes are the site of hemocyanin or hemoglobin biosynthesis in gastropods. Based on electron microscopy, we recently proposed a possible pathway of hemoglobin exocytosis through the slit apparatus, and provided molecular evidence of a common phylogenetic origin of molluscan rhogocytes, insect nephrocytes and vertebrate podocytes. However, the previously proposed secretion mode of the respiratory proteins into the hemolymph is still rather hypothetical, and the possible role of rhogocytes in detoxification requires additional data. Although our previous study on rhogocytes of the red-blooded (hemoglobin-containing freshwater snail Biomphalaria glabrata provided much new information, a disadvantage was that the hemoglobin molecules were not unequivocally defined in the electron microscope. This made it difficult to trace the exocytosis pathway of this protein. Therefore, we have now performed a similar study on the rhogocytes of the blue-blooded (hemocyanin-containing freshwater snail Lymnaea stagnalis. The intracellular hemocyanin could be identified in the electron microscope, either as individual molecules or as pseudo-crystalline arrays. Based on 3D-electron microscopy, and supplemented by in situ hybridization, immunocytochemistry and stress response experiments, we provide here additional details on the structure and hemocyanin biosynthesis of rhogocytes, and on their response in animals under cadmium and starvation stress. Moreover, we present an advanced model on the release of synthesized

  7. Effect of self-fertilization on Biomphalaria tenagophila (Orbigny, 1835) (Pulmonata: Planorbidae)

    OpenAIRE

    Tuan Roseli; Simões Luiz Carlos Gomes

    1998-01-01

    Biomphalaria tenagophila is a simultaneous hermaphrodite freshwater snail, which can breed by self and cross-fertilization. It is, therefore, well suited for studying reproduction as an evolutive strategy. Several characteristics (shell size and age at sexual maturity, egg fecundity and fertility) were analyzed in four consecutive self-fertilized generations and compared to cross-fertilized individuals. The reproductive parameters were similar in the two groups. Shell size was significantly g...

  8. Growth changes induced by gamma radiation on Biomphalaria straminea (Dunker, 1848)

    OpenAIRE

    1999-01-01

    Doses of 60Co gamma radiation with 2.5; 5; 7.5; 10; 15; 20; 25; 30; 35; 40; 45; 50; 55; 60; 80; 160; 320 and 640 Gy were applied to 1,080 snails Biomphalaria straminea, an intermediate host of Schistosoma mansoni, divided in groups containing 30 mollusks. In addition, 60 non irradiated snails were kept as control. Fifty percent of the population was kept in colonies (allowing cross fertilization) while the other half was maintained in sexual isolation (allowing self fertilization) and during ...

  9. Malacological survey and geographical distribution of vector snails for schistosomiasis within informal settlements of Kisumu City, western Kenya

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    Opisa Selpha

    2011-12-01

    Full Text Available Abstract Background Although schistosomiasis is generally considered a rural phenomenon, infections have been reported within urban settings. Based on observations of high prevalence of Schistosoma mansoni infection in schools within the informal settlements of Kisumu City, a follow-up malacological survey incorporating 81 sites within 6 informal settlements of the City was conducted to determine the presence of intermediate host snails and ascertain whether active transmission was occurring within these areas. Methods Surveyed sites were mapped using a geographical information system. Cercaria shedding was determined from snails and species of snails identified based on shell morphology. Vegetation cover and presence of algal mass at the sites was recorded, and the physico-chemical characteristics of the water including pH and temperature were determined using a pH meter with a glass electrode and a temperature probe. Results Out of 1,059 snails collected, 407 (38.4% were putatively identified as Biomphalaria sudanica, 425 (40.1% as Biomphalaria pfeifferi and 227 (21.5% as Bulinus globosus. The spatial distribution of snails was clustered, with few sites accounting for most of the snails. The highest snail abundance was recorded in Nyamasaria (543 snails followed by Nyalenda B (313 snails. As expected, the mean snail abundance was higher along the lakeshore (18 ± 12 snails compared to inland sites (dams, rivers and springs (11 ± 32 snails (F1, 79 = 38.8, P Biomphalaria snails was higher in the inland (2.7% compared to the lakeshore sites (0.3% (P = 0.0109. B. sudanica was more abundant in sites along the lakeshore whereas B. pfeifferi and B. globosus were more abundant in the inland sites. Biomphalaria and Bulinus snails were found at 16 and 11 out of the 56 inland sites, respectively. Conclusions The high abundance of Biomphalaria and Bulinus spp. as well as observation of field-caught snails shedding cercariae confirmed that besides Lake

  10. Biomphalaria straminea no Peru e sua suscetibilidade a cepas brasileiras de Schistosoma mansoni

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    C.A. Cuba Cuba

    1977-12-01

    Full Text Available Em Maio de 1973, um dos autores (C.A.C. coletou na localidade de Imacita, Província de Bagua, Departamento de Amazonas, vários espécimes de Biomphalaria straminea (Dunker, 1848, uma espécie que, até então, não havia sido assinalada no Peru. Descendentes destes indivíduos foram submetidos a provas de suscetibilidade às cepas BH e SJ de Schistosoma mansoni que, em condições naturais, evoluem em B. glabrata de Belo Horizonte e B. tenagophila de São José dos Campos, respectivamente. Oitenta espécimens foram expostos à cepa BH dos quais em 13 ou 16,2% a infecção evoluiu caracteristicamente até a formação de esporocistos secundários sem haver, contudo, eliminação de cercárias, mesmo no indivíduo que apresentou uma sobrevivência de 88 dias após a exposição. Não se verificou cura espontânea neste lote. Entre as 40 B. straminea expostas à cepa SJ 9 ou 22,5% infectaram-se, sendo que apenas duas eliminaram poucas cercárias aos 57 e 77 dias após a exposição, por dois dias consecutivos, tendo uma morrido e uma se curado espontaneamente. A cura espontânea do parasitismo foi notado em mais dois indivíduos, nos quais a infecção foi observada através da concha. Cortes histológicos seriados de 9 caramujos, expostos individualmente a 50 miracídios da cepa BH e fixados entre 6 e 120 horas após a exposição, mostraram esporocistos em desenvolvimento e esporocistos invadidos por amebócitos, sem formação de granulomas por parte do hospedeiro, fato assinalado em caramujos suscetíveis. A população estudada comportou-se experimentalmente de modo semelhante a outras populações de B. straminea testadas em laboratório, isto é, com baixa suscetibilidade, embora tal comportamento não afaste a possibilidade dela vir a manter o ciclo do parasita em sua área de distribuição.In May 1973 one of the Authors (C.A.C. collected specimens of Biomphalaria straminea (Dunker 1848 at imacita, Bagua Province, Amazonas, Pem. This

  11. Biological control of Biomphalaria tenagophila (Mollusca, Planorbidae), a schistosomiasis vector, using the fish Geophagus brasiliensis (Pisces, Cichlidae) in the laboratory or in a seminatural environment

    OpenAIRE

    Marcia Weinzettl; Pedro Jurberg

    1990-01-01

    In order to investigate a possible method of biological control of schistosomiasis, we used the fish Geophagus brasiliensis (Quoy & Gaimard, 1824) which is widely distributed throughout Brazil, to interrupt the life cycle of the snail Biomphalaria tenagophila (Orbigny, 1835), an intermediate host of Schistosoma mansoni. In the laboratory, predation eliminated 97.6% of the smaller snails (3-8 mm shell diameter) and 9.2% of the larger ones (12-14 mm shell diameter). Very promising results were ...

  12. Environmental epidemiology of intestinal schistosomiasis in Uganda: population dynamics of biomphalaria (gastropoda: planorbidae) in Lake Albert and Lake Victoria with observations on natural infections with digenetic trematodes.

    Science.gov (United States)

    Rowel, Candia; Fred, Besigye; Betson, Martha; Sousa-Figueiredo, Jose C; Kabatereine, Narcis B; Stothard, J Russell

    2015-01-01

    This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni) or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P < 0.001) in both lakes and negative relationship with conductivity (P = 0.04) in Lake Albert. Of the Biomphalaria collected in Lake Albert (N = 6,183), 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria (N = 13,172) were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene. PMID:25705680

  13. Biomphalaria alexandrina as a bioindicator of metal toxicity.

    Science.gov (United States)

    Habib, Mohamed R; Mohamed, Azza H; Osman, Gamalat Y; Mossalem, Hanan S; Sharaf El-Din, Ahmed T; Croll, Roger P

    2016-08-01

    Heavy metals are common environmental pollutants to the aquatic ecosystems. Several aquatic species have been used as bioindicators and biomonitoring subjects for heavy metals pollution. In the present study, the effects of cadmium (Cd) and manganese (Mn) on the survival, attachment, locomotion, and feeding behaviours of the gastropod snail Biomphalaria alexandrina were determined. The short-term (96 h) LC50 for Cd and Mn were found to be 0.219 and 154.2 mg/l, respectively. Long-term exposures (16-20 days) to ascending concentrations of Cd (0.01-1 mg/l) and Mn (50-500 mg/l) also caused gradual decreases in the survival rate of B. alexandrina in a dose-dependent manner. Attachment, locomotion and feeding behaviours of snails exposed to lethal and sublethal concentrations of Cd and Mn at acute (96 h) and chronic exposure (24 days) intervals, respectively, were also recorded. Compared to controls, a significant decrease (p ≤ 0.05) was recorded in the different behaviours of exposed snails. These changes in behaviour would potentially impact the snail's ability to survive in the wild. Although Cd caused a more severe decline in snail survivorship than Mn, the behavioural effects of Mn were much more severe than Cd when the metals were roughly matched for lethality. In sum, the present study demonstrates B. alexandrina to be a sensitive bioindicator and model organism to assess heavy metals risk factors for severe toxicity in freshwater ecosystems. PMID:27209558

  14. Modification of Biomphalaria straminea eggs enclose induced by gamma radiation

    International Nuclear Information System (INIS)

    A vector of Schistosomiasis, the mollusk Biomphalaria straminea, can procreate by means of sexual - when in colonies - or by hermaphrodite fecundation, if isolated. In order to study its reproductive behavior under gamma radiation, 540 snails kept in colony and 540 maintained isolated in individual aquariums, were irradiated with doses, 0, 2,5, 5,0, 7,5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 80, 160, 320 and 640 Gy of gamma-rays from a 60 Co. source, and were observed during 30 days. Daily, the off spring were collected from the aquariums, its eggs counted and maintained in Petri's plate, in water. After eight days, the eggs were counted again and the difference with the first count representing the hatched eggs. As a result, the eggs from the snails kept in colony showed a greater number of encloses than those from the isolated snails, ranging from 2,5 to 40 Gy. Beyond this dose the difference between the two observed groups were statistically non significant, leading to suppose a greater resistance of the sexually fecundation to the influence of gamma-rays. (author). 16 refs, 1 fig, 1 tab

  15. Interaction between primary and secondary sporocysts of Schistosoma mansoni and the internal defence system of Biomphalaria resistant and susceptible to the parasite

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    Ana Carolina Alves de Mattos

    2011-06-01

    Full Text Available The outcome of the interaction between Biomphalaria and Schistosoma mansoni depends on the response of the host internal defence system (IDS and the escape mechanisms of the parasite. The aim of this study was to evaluate the responsiveness of the IDS (haemocytes and soluble haemolymph factors of resistant and susceptible Biomphalaria tenagophila lineages and Biomphalaria glabrata lineages in the presence of in vitro-transformed primary sporocysts and secondary sporocysts obtained from infected B. glabrata. To do this, we assayed the cellular adhesion index (CAI, analysed viability/mortality, used fluorescent markers to evaluate the tegumental damage and transplanted secondary sporocysts. B. tenagophila Taim was more effective against primary and secondary sporocystes than the susceptible lineage and B. glabrata. Compared with secondary sporocysts exposed to B. tenagophila, primary sporocysts showed a higher CAI, a greater percentage of dead sporocysts and were labelled by lectin from Glycine max and Alexa-Fluor 488 fluorescent probes at a higher rate than the secondary sporocysts. However, the two B. tenagophila lineages showed no cercarial shedding after inoculation with secondary sporocysts. Our hypothesis that secondary sporocysts can escape the B. tenagophila IDS cannot be confirmed by the transplantation experiments. These data suggest that there are additional mechanisms involved in the lower susceptibilty of B. tenagophila to S. mansoni infection.

  16. Growth changes induced by gamma radiation on Biomphalaria straminea (Dunker, 1848

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    Motta Mauricy A da

    1999-01-01

    Full Text Available Doses of 60Co gamma radiation with 2.5; 5; 7.5; 10; 15; 20; 25; 30; 35; 40; 45; 50; 55; 60; 80; 160; 320 and 640 Gy were applied to 1,080 snails Biomphalaria straminea, an intermediate host of Schistosoma mansoni, divided in groups containing 30 mollusks. In addition, 60 non irradiated snails were kept as control. Fifty percent of the population was kept in colonies (allowing cross fertilization while the other half was maintained in sexual isolation (allowing self fertilization and during one month their growth was observed through the daily measurement of the shell diameter. Results showed that after 20 Gy doses the growth in shell diameter of irradiated snails was greater than that of the control group after 30 days. At this dose the snail size was the greatest, among all isolated groups. The 80 Gy doses also induced the final shell diameter of isolated snails to be greater then that observed in the control groups. As this effect was most evident among the isolated snails, a possible hormonal role may have been involved in the observed phenomena, which is under investigation with the objective of identifying any future applications that this could have to schistosomiasis control.

  17. Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

    Directory of Open Access Journals (Sweden)

    Candia Rowel

    2015-01-01

    Full Text Available This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P<0.001 in both lakes and negative relationship with conductivity (P=0.04 in Lake Albert. Of the Biomphalaria collected in Lake Albert N=6,183, 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria  N=13,172 were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene.

  18. Large-scale determinants of intestinal schistosomiasis and intermediate host snail distribution across Africa

    DEFF Research Database (Denmark)

    Stensgaard, Anna-Sofie; Utzinger, Jürg; Vounatsou, Penelope;

    2013-01-01

    for infectious disease transmission. However, the transmission of infectious diseases is governed by a myriad of ecological, economic, evolutionary and social factors. Hence, a deeper understanding of the total disease system (pathogens, vectors and hosts) and its drivers is important for predicting...... responses to climate change. Here, we combine a growing degree day model for Schistosoma mansoni with species distribution models for the intermediate host snail (Biomphalaria spp.) to investigate large-scale environmental determinants of the distribution of the African S. mansoni-Biomphalaria system and...... potential impacts of climatic changes. Snail species distribution models included several combinations of climatic and habitat-related predictors; the latter divided into "natural" and "human-impacted" habitat variables to measure anthropogenic influence. The predictive performance of the combined snail...

  19. Actividad molusquicida del Piquerol A aislado de Piqueria trinervia (compositae sobre ocho especies de caracoles pulmonados The molluscicide activity of Piquerol A isolated from Piqueria trinervia (Compositae against eight species of pulmonate snails

    Directory of Open Access Journals (Sweden)

    Alejandro Cruz-Reys

    1989-03-01

    Full Text Available De las partes aéreas de la planta Piqueria trinervia (Compositae colectada en diveresas áereas de México, se aisló el Piquerol A. Este compuesto se probó como agente molusquicida contra ocho especies de caracoles pulmonados: Fossaria (Fossaria humilis, F. (Bakerilymnae sp., Pseudosuccinea columella, Stagnicola attenuata, de México; F. (B. cubensis y Physacubensis, de Cuba; P. Columella y Biomphalaria glabrata, de Brasil; B glabrata, de Puerto Rico; S. elodes, de Estados Unidos. Se utilizaron tres concentraciones 50, 25 y 5 ppm para cada una de las especies y 2 períodos de exposición, 6 y 24 horas, a 20-22ºC. En 50 ppm, después de 6 horas, y 25 ppm, después de 24 horas los ejemplares de todas las especies murieron. En 5 ppm después de 24 horas, se observaron mortalidades de 60 a 100%. En ningún caso se observó recuperación después de la exposición por 24 horas. El piquerol A es un terpeno biodegradable que presenta otras actividades biológicas. No se han hecho pruebas de toxicidad en otros animales ni pruebas de campo. Sin embargo, es una substacia con alto potencial de uso como molusquicida en zonas de transmisión focal. Es la primera que en México se hacen estudios sistemáticos sobre molusquicidas de origen vegetal.In laboratory trials an aqueous solution of Piquerol A from Piqueria trinervia, collected in several regions of Mexico, showed a molluscicide action on the adults of eight different pulmonates snails species. Fossaria (Fossaria humilis, F. (Bakerilymnaea sp., Pseudosuccinea columella and Stagnicola attenuata from Mexico; F. (B. cubensis and Physa cubensis from Cuba; P. columella and Biomphalaria glabrata from Brazil; B. glabrata from Puerto Rico; and S. elodes from USA. The solution was tested at 50, 25 and 5 ppm concentration, for two periods of 6 and 24 hours, at room temperature (20-22ºC. A 100% mortality was obtained for all species at 50 ppm concentration after 6 hours of exposure; the same percentage at 25

  20. Biomphalaria subprona (Martens, 1899) (Gastropoda: Planorbidae)

    OpenAIRE

    W. Lobato Paraense

    1996-01-01

    A description is given of the shell, head-foot, pulmonary wall, reproductive system and radula of Biomphalaria subprona (Martens, 1899). A diagnosis between it and two other congeneric species under 10 mm in shell diameter occurring in Middle America (Biomphalaria helophila and B. schrammi) is presented.

  1. Susceptibility of Biomphalaria amazonica and Biomphalaria occidentalis from Manso Dam, Mato Grosso, Brazil to infection with three strains of Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Monica Ammon Fernandez

    2006-10-01

    Full Text Available As well as malaria and yellow fever, schistosomiasis is one of the main endemic diseases associated to environments which suffered some impact related to the development of great economic projects, as for example the construction of hydroelectric power stations. Aiming to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area which suffered impact from the Manso hydroelectric power station a survey was performed during the period of 2002 to 2003 and revealed the occurrence of populations of Biomphalaria amazonica and Biomphalaria occidentalis. Studies on parasite-mollusc compatibility were undertaken using five B. amazonica colonies (Barão de Melgaço, Poconé, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Manso and Casca rivers, and four B. occidentalis colonies (Cuiabá, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Água Fria district and Casca river were exposed to miracidia of Schistosoma mansoni. Of 257 snails of B. amazonica used, 17 became infected (infection index of 6.61% and all specimens of B. occidentalis proved unsusceptible. According to the strains used, of the 158 snails exposed to BH miracidia, 6 became infected (3.79%; of the 44 exposed to SJ miracidia, 6 became infected (13.63%; and of the 55 snails of B. amazonica exposed to EC miracidia, 5 became infected (9.09%. These results point out the low possibility of introduction of schistosomiasis in those areas, but we believe it can not be discarded as due the presence of B. amazonica.

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

    Science.gov (United States)

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

    2016-09-01

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

  3. Breeding of Biomphalaria tenagophila in mass scale Criação em larga escala de Biomphalaria tenagophila

    Directory of Open Access Journals (Sweden)

    Florence Mara Rosa

    2013-02-01

    Full Text Available An efficient method for breeding Biomphalaria tenagophila (Taim lineage/RS was developed over a 5-year-period (2005-2010. Special facilities were provided which consisted of four cement tanks (9.4 x 0.6 x 0.22 m, with their bottom covered with a layer of sterilized red earth and calcium carbonate. Standard measures were adopted, as follows: each tank should contain an average of 3000 specimens, and would be provided with a daily ration of 35,000 mg complemented with lettuce. A green-house effect heating system was developed which constituted of movable dark canvas covers, which allowed the temperature to be controlled between 20 - 24 ºC. This system was essential, especially during the coldest months of the year. Approximately 27,000 specimens with a diameter of 12 mm or more were produced during a 14-month-period. The mortality rates of the newly-hatched and adult snails were 77% and 37%, respectively. The follow-up of the development system related to 310 specimens of B. tenagophila demonstrated that 70-day-old snails reached an average of 17.0 ± 0.9 mm diameter. The mortality rates and the development performance of B. tenagophila snails can be considered as highly satisfactory, when compared with other results in literature related to works carried out with different species of the genus Biomphalaria, under controlled laboratory conditions.Foi desenvolvido um método eficiente de criação em larga escala de Biomphalaria tenagophila (linhagem Taim/RS durante o período de 2005-2010. Foi concebida uma instalação que consiste de quatro tanques de alvenaria (9,4 x 0,6 x 0,22 com fundos recobertos por uma mistura constituída de terra vermelha esterilizada e carbonato de cálcio. Foi padronizado que cada tanque de criação conteria em média 3.000 exemplares e receberia diariamente 35.000 mg de ração e alface como complemento. O desenvolvimento de um sistema de aquecimento por efeito estufa constituído de lonas escuras móveis permitiu

  4. Freshwater snails and Schistosomiasis mansoni in the state of Rio de Janeiro, Brazil: III - Baixadas Mesoregion

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    Silvana C Thiengo

    2002-10-01

    Full Text Available In this paper, the third of a series dealing with the survey of freshwater gastropods of the state of Rio de Janeiro, the results of collections carried out in the Mesoregion Baixadas from 2000 to 2002 are presented. Twenty-two species, belonging to seven families, were found. As to the snail intermediate hosts of Schistosoma mansoni, the most frequent species was Biomphalaria tenagophila besides some new findings of Biomphalaria straminea. No specimens were found harboring larval forms of S. mansoni although different kinds of cercariae had been observed.

  5. Effect of self-fertilization on Biomphalaria tenagophila (Orbigny, 1835 (Pulmonata: Planorbidae

    Directory of Open Access Journals (Sweden)

    Tuan Roseli

    1998-01-01

    Full Text Available Biomphalaria tenagophila is a simultaneous hermaphrodite freshwater snail, which can breed by self and cross-fertilization. It is, therefore, well suited for studying reproduction as an evolutive strategy. Several characteristics (shell size and age at sexual maturity, egg fecundity and fertility were analyzed in four consecutive self-fertilized generations and compared to cross-fertilized individuals. The reproductive parameters were similar in the two groups. Shell size was significantly greater in the fourth self-fertilized generation than in the cross-fertilized individuals.

  6. Molluscicidal saponins from a Zimbabwean strain of Phytolacca dodecandra

    DEFF Research Database (Denmark)

    Thiilborg, S. T.; Christensen, S. B.; Cornett, Claus;

    1994-01-01

    -hydroxyoleanolic acid. Two of the saponins were submitted to a preliminary screening for molluscicidal activity against the schistosomiasis transmitting snail Biomphalaria glabrata and showed, respectively, strong and weak activity. In addition, four saponins previously reported from other strains of Phytolacca...

  7. Molluscicidal activity of chlorophyll extraction against the freshwater snails

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    Mona Said Mahmoud

    2013-09-01

    Full Text Available Objective: To evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against the snails Lymnaea stagnalis, Biomphalaria spp. and Physa marmorata. Methods: Chlorophyllin was extracted from deep-frozen spinach. Snails were incubated in chlorophyllin containing water with 2.5, 5.0, 10.0 and 15.0 µg/mL. All samples were kept in darkness overnight for incubation. After incubation, three samples were irradiated with simulated solar radiation for 3 h. After irradiation, the vitality of the organisms was determined. Results: The photodynamically active chlorophyllin, at low concentrations, was able to kill snails within a few hours under exposure of solar radiation. Besides, it had a killing effect by about 70% and 100% on the snails’ eggs and the newly hatched snails, respectively, after 3 h exposure to solar radiation. Conclusion: The derivates of chlorophyll was a very interesting substance for photodynamic freshwater snail control. Hence, it might be a promising and cheap new strategy which probably had the potential to replace the synthetic molluscicides for snail control.

  8. The Influence of Self-fertilization performance and Copulation Behaviour in Reproduction by Cross-fertilization in Groups of Biomphalaria tenagophila (Mollusca, Planorbidae

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    Freitas June Springer de

    1997-01-01

    Full Text Available The following hypotheses were tested for groups of simultaneous hermaphrodites Biomphalaria tenagophila: (a snails that have low reproductive success during the process of self-fertilization do not increase their reproductive success after the end of grouping; (b the copulation behaviour and the presence of one snail whose eggs have a low viability rate influence the partner's reproductive success by cross-fertilization. Groups were constituted by a homozygous pigmented snail and two albinos: one with a viability rate higher than 70% ("good reproducers" and the other less than 10% ("bad reproducers". All pigmented snails had viability rates higher than 70%. The "good" and "bad" reproducer albino snails had similar copulation behaviour. However, after the end of grouping, the "bad reproducers" continued to have viability rates less than 10% over 30 days. In 100% of the cases that pigmented snails copulated (performing either a male role or simultaneously male and female roles exclusively with "good" reproducer albinos, they presented high reproductive success (producing, on average of 8.4 pigmented embryos/egg-mass. However, in 100% of the cases that pigmented snails copulated with both partners, the "good" reproducer albino snails produced none or very few embryos (the highest average was 2.2 pigmented embryos/egg-mass. Therefore, the production of viable embryos by cross-fertilization was more influenced by self-fertilization performance than by copulation behaviour. The presence of a snail whose eggs have a low viability rate could decrease their partners reproductive success

  9. Susceptibility and compatibility of Biomphalaria tenagophila from the Río de la Plata basin with Schistosoma mansoni from Brazil.

    Science.gov (United States)

    Borda, Carlos Edgardo; Rea, María Josefa F

    2010-07-01

    Schistosomiasis has expanded to southern parts of Brazil. Between 2005-2007 the dispersion and the proliferation of Biomphalaria tenagophila was verified in the province of Corrientes near the Brazilian border. In order to study the possibility that schistosomiasis might spread into the basins of the Paraná and Uruguay Rivers, 440 B. tenagophila collected from 10 populations groups were experimentally exposed to infection with Schistosoma mansoni of the SJ2 strain. Snails from five localities were susceptible. Frandsen's index (TCP/100) shows that those snails from Mirungá (11%), Aguacerito (2%) and Curupicay (2%) were Class I and not very compatible. Meanwhile, snails from Copra (6%) and Pay-Ubre (22%), in the Paraná River basin, were Class II and poorly compatible. PMID:20721498

  10. Susceptibility and compatibility of Biomphalaria tenagophila from the Río de la Plata basin with Schistosoma mansoni from Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Edgardo Borda

    2010-07-01

    Full Text Available Schistosomiasis has expanded to southern parts of Brazil. Between 2005-2007 the dispersion and the proliferation of Biomphalaria tenagophila was verified in the province of Corrientes near the Brazilian border. In order to study the possibility that schistosomiasis might spread into the basins of the Paraná and Uruguay Rivers, 440 B. tenagophila collected from 10 populations groups were experimentally exposed to infection with Schistosoma mansoni of the SJ2 strain. Snails from five localities were susceptible. Frandsen's index (TCP/100 shows that those snails from Mirungá (11%, Aguacerito (2% and Curupicay (2% were Class I and not very compatible. Meanwhile, snails from Copra (6% and Pay-Ubre (22%, in the Paraná River basin, were Class II and poorly compatible.

  11. Ciclo biológico de Paraibatrema inesperata n.g., n.sp. (Trematoda, Paramphistomidae, a partir de metacercárias desenvolvidas em Biomphalaria tenagophila (D'Orbigny, 1835 (Mollusca, Planorbidae

    Directory of Open Access Journals (Sweden)

    Marlene Tiduko Ueta

    1981-03-01

    Full Text Available Em exemplares de B. tenagophila, capturados em ambiente natural, foram encontradas paranfistomocercárias de precoce encistamento. Procedeu-se à infecção, per os, de animais de biotério; em camundongos e ratos, verificou-se o desenvolviemnto de trematóide paranfistomídeo desconhecido e que, por suas características, não se enquadra nos g~eneros conhecidos de Paramphistomidae de mamíferos. Para o parasito em apreço é proposta a denominação Paraibatema inesperata n.g, n.sp.. A partir de miracídios, oriundos de ovos eliminados pelos roedores em experiência, procurou-se infectar B. tenagophila e B. glabrata, criadas no moluscário. Verificou-se ser ativa a penetração dos miracídios no tecido do molusco, sendo freqüente a formação de tumorações nas antenas. A evolução experimental no hospedeiro intermediário apresenta-se lenta; ao fim de 40 dias de pós-infecção, não se observou a formação de esporocistos, rédias e cercárias.The new genus and new species of paramphistomid trematode, Paraibatrema inesperata n.g, n.sp., are proposed. The parasite was originally found as a quickly encysting paramphistome cercaria from specimens of the planorbid snail Biomphalaria tenagophila caught in natural habitats. Experimental infection resulted from intubation of metacercariae into the stomach of white mice and rats, which passed eggs in the feces 20 days later. Specimens of B. tenagophila and B. glabrata have been exposed to miracidia from eggs passed by mice. Penetration of the molluscan tegument was observed, but it seems that the larval development of the parasite is slow, inasmuch as no rediae and cercariae have been obtained as yet.

  12. Ocorrência de Biomphalaria straminea (Pulmonata: Planorbidae na estação de aqüicultura do IBAMA em Uberlândia, MG

    Directory of Open Access Journals (Sweden)

    Elisângela de Paula Silveira

    1997-10-01

    Full Text Available Este trabalho avalia a ocorrência de moluscos planorbídeos na estação de psicultura do IBAMA em Uberlândia, Minas Gerais. Constatou-se a presença de Biomphalaria straminea em 39,5% dos tanques de criação. Nenhum dos caramujos estava infectado por Schistosoma mansoni, mas investigações complementares devem ser realizadas na área.This work evaluates the occurrence of freshwater snails in the IBAMA's fish breeding station in Uberlandia, Minas Gerais State. We verified the presence of Biomphalaria straminea in 39.5% of all breeding tanks. None of the snails were infected by Schistosoma mansoni, but futher investigation should be done in the area.

  13. Effects of Varying Concentrations of the Crude Aqueous and Ethanolic Extracts of Dalbergia Sissoo Plant Parts on Biomphalaria Pfeifferi Egg Masses

    OpenAIRE

    Adenusi, Adedotun A; Odaibo, Alexander B

    2009-01-01

    This study evaluated, using replicated laboratory bioassays, the toxicities of the crude aqueous and ethanolic extracts of Dalbergia sissoo Roxb. 1832 (family Leguminosae) fruits, leaves, roots and stem bark against egg masses of Biomphalaria pfeifferi (Krauss, 1848), the snail intermediate host of Schistosoma mansoni (Sambon, 1907) in Nigeria. Viable 0–24 hr-old embryonated egg masses were separately exposed to five different concentrations (7.81–2000 mg/l) of extracts for 24 hrs, washed in ...

  14. Modification of Biomphalaria straminea eggs enclose induced by gamma radiation; Modificacoes da eclosao de ovos de Biomphalaria straminea induzidas pela radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Melo, A.M.M.A.; Leal, M.A.M.; Motta, M.A. da [Pernambuco Univ., Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia

    1994-12-31

    A vector of Schistosomiasis, the mollusk Biomphalaria straminea, can procreate by means of sexual - when in colonies - or by hermaphrodite fecundation, if isolated. In order to study its reproductive behavior under gamma radiation, 540 snails kept in colony and 540 maintained isolated in individual aquariums, were irradiated with doses, 0, 2,5, 5,0, 7,5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 80, 160, 320 and 640 Gy of gamma-rays from a {sup 60} Co. source, and were observed during 30 days. Daily, the off spring were collected from the aquariums, its eggs counted and maintained in Petri`s plate, in water. After eight days, the eggs were counted again and the difference with the first count representing the hatched eggs. As a result, the eggs from the snails kept in colony showed a greater number of encloses than those from the isolated snails, ranging from 2,5 to 40 Gy. Beyond this dose the difference between the two observed groups were statistically non significant, leading to suppose a greater resistance of the sexually fecundation to the influence of gamma-rays. (author). 16 refs, 1 fig, 1 tab.

  15. Isolamento genético de populações de caramujos do gênero Biomphalaria

    Directory of Open Access Journals (Sweden)

    Aluízio Bezerra Coutinho

    1976-08-01

    Full Text Available Experiências de intrecruzamento de caramujos do gênero Biomphalaria de várias procedências de Pernambuco, Brasil, utilizando o albinismo como mercador genético mostraram que ocorre na região duas populações isoladas que não se intercruzam. Uma das populações è constituída por caramujos que podem atingir diâmetros de concha até em torno de 30 mm, enquanto que a outra atinge somente em torno de 10 mm mesmo nas melhores condições ambientais.Breending experiments with snails of the genus Biomphalaria from several beeding sites in Pernambuco, Brazil, using albinism as the genetics tag have shown that two isolated non-interbreeding populations occur in the region. One of the populations is made up of snails which consistently reached diameter sizes around 30 mm, while the other of snails reaching only around 10 mm shell diameter, even when in the best environmental conditions.

  16. Freshwater snails and schistosomiasis mansoni in the State of Rio de Janeiro, Brazil: I - metropolitan mesoregion

    Directory of Open Access Journals (Sweden)

    Thiengo Silvana C

    2001-01-01

    Full Text Available In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954; Biomphalaria glabrata (Say, 1818; Biomphalaria schrammi (Crosse, 1864; Biomphalaria straminea (Dunker, 1848; Biomphalaria tenagophila (Orbigny, 1835; Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835; Drepanotrema cimex (Moricand, 1839; Drepanotrema lucidum (Pfeiffer, 1839; Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962; Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774; Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822; Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.

  17. Studies on the molluscicidal activity of Agave angustifolia and Pittosporum tobira on schistosomiasis transmitting snails.

    Science.gov (United States)

    Ibrahim, Abdalla M; Abdel-Gawad, Mahfouz M; El-Nahas, Hanan A; Osman, Nadia S

    2015-04-01

    In the search for new molluscicidal plants for controlling the snail vectors of schistosomiasis, laboratory evaluation was made to assess the molluscicidal activity of Agave angustifolia and Pittosporum tobira plants against Biomphalaria alexandrina snails. Results indicated that both plants have promising molluscicidal activity as the LC90 of the dry powder of both plants was 120 ppm. Both plants showed marked cercaricidal and miracidicidal potencies against S. mansoni larvae. The LC90 of both plants (120 ppm) killed most B. alexandrina eggs within 24 h of exposure. The sub-lethal concentrations of both plants markedly suppressed the survival rate of B. alexandrina snails and the mortality increased with increasing the concentrations and the exposure period up to 10 successive weeks. The accumulative toxic effect of these concentrations was continuous during the recovery period. Also, the reproductive rates of exposed snails were greatly affected even through the recovery period. This depression in reproductive ability of snails was accompanied by histological damage in the hermaphrodite glands of exposed snails. Meanwhile, the growth of snails was estimated weekly and it showed great inhibition in exposed snails comparing with the control ones. PMID:26012228

  18. The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: Implications for developing new model organisms

    OpenAIRE

    Satwant Kaur; Susan Jobling; Jones, Catherine S.; Noble, Leslie R; Routledge, Edwin J.; Lockyer, Anne E.

    2015-01-01

    © 2015 Kaur et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited Nuclear receptors (NRs) are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully seque...

  19. Spatial and seasonal trends of a natural population of Biomphalaria occidentalis in northeastern Argentina

    Directory of Open Access Journals (Sweden)

    Alejandra Rumi

    1992-06-01

    Full Text Available This study aims to analyze the age of a population of Biomphalaria occidentalis on a pound of Riachuelo river basin, wich is one of the three most important Middle Paraná river affluents in Corrientes province. Samples were drawn from three stations, were spatial and temporal numerical variations of the snail, as well as its relation with different environmental parameters, mainly temperature, rainfall, pH and conductivity, were analyzed. Snail abundance is given in number of individuals/hour. The differences between the three sampling stations, estimated by nonparametric tests, was nonsignificant. A relative scale to the greatest shell diameter was employed to build the age pyramids. Temporal fluctuations of snail abundance correlated negatively with the highest monthly accumulated temperatures (P < 0.05. Although different floristic compositions were observed at the three stations, no significant numerical variations were detected in B. occidentalis spatial distribution. Reproductive activity took place between March-April and November with overlapping cohort system. During summer (December-Febuary mortality increased along with temperature and reproductive activity was not evident.

  20. Actividad molusquicida del Piquerol A aislado de Piqueria trinervia (compositae) sobre ocho especies de caracoles pulmonados The molluscicide activity of Piquerol A isolated from Piqueria trinervia (Compositae) against eight species of pulmonate snails

    OpenAIRE

    Alejandro Cruz-Reys; Carolina Chavarin; Martha P. Campos Arias; Javier Taboada; Manuel Jímenez E.

    1989-01-01

    De las partes aéreas de la planta Piqueria trinervia (Compositae) colectada en diveresas áereas de México, se aisló el Piquerol A. Este compuesto se probó como agente molusquicida contra ocho especies de caracoles pulmonados: Fossaria (Fossaria) humilis, F. (Bakerilymnae) sp., Pseudosuccinea columella, Stagnicola attenuata, de México; F. (B.) cubensis y Physacubensis, de Cuba; P. Columella y Biomphalaria glabrata, de Brasil; B glabrata, de Puerto Rico; S. elodes, de Estados Unidos. Se utiliza...

  1. New polymeric formulation for control of biomphalaria Alexandria based on pharmaceutical waste gelatin

    International Nuclear Information System (INIS)

    In the recent years, important new areas of application for plastics have emerged in medicine such as devices for the controlled release of drugs. The increases in the use of plastic materials in all sectors of industry have led to a continuous increase in the generation of plastic wastes. Recycling allow the waste to be reintroduced into the consumption cycle. Pharmaceutical companies which manufacture soft gels with different shapes, sizes and colors based mainly on gelatin formulations produce huge amount of gelatin waste. Schistosomiasis is one of the most important public health problems in our country. We now report the utilization of gelatin scrap by incorporating them in biodegradable films containing the molluscicide niclosamide for control of Biomphalaria Alexandrina snails. The preparation of the gelatin films will be described. The release of niclosamide from the prepared blends was investigated. The prepared formulations proved to be useful compared with free niclosamide

  2. Distribution of freshwater snails in the river Niger basin in Mali with special reference to the intermediate hosts of schistosomes

    DEFF Research Database (Denmark)

    Madsen, Henry; Coulibaly, Godefroy; Furu, Peter

    1987-01-01

    densities appeared to be associated with human water contact activities, which apparently create favourable biotopes for the snails. This is probably due to an alteration of the vegetation and an increase of the trophic status of the site by contamination with food remnants and other debris. The larger...... irrigation canals or lakes in these schemes play an important role in the transmission of human schistosomes and transmission appears to be very focal in these habitats. Infected snails are almost exclusively found in well-defined human water contact sites (WCS). Local infection rates with schistosomes were......Snail surveys were carried out in various parts of Mali. All areas surveyed are part of the Niger basin being either affluents or irrigation schemes fed by this river. The snail species present varied greatly between areas. The following potential hosts of schistosomes were recorded: Biomphalaria...

  3. Potential schistosome-vector snails and associated trematodes in ricefields of Corrients province, Argentina. Preliminary results.

    Science.gov (United States)

    Rumi, A; Hamann, M I

    1990-01-01

    Considering the possibility of introduction of schistosomiasis mansoni into Argentina as a consequence of dam construction on the Rio De La Plata basin, preliminary studies have been carried out on agrosystems such as ricefields in Corrientes province with the following purposes: 1) to survey and estimate the relative abundance of planorbids and identify potential vector species; 2) to identify environmental factors capable of influencing Biomphalaria population dynamics; and 3) to find out snail-parasite associations and estimate snail infection rates in order to detect possible competitive interactions between larval stages of native trematodes that could be used in biological control of Schistosoma mansoni. Three potential schistosome vectors were detected in ricefields, namely Biomphalaria straminea, B. tenagophila and B. peregrina, although B. orbignyi, a species refractory to infection with S. mansoni, proved the most frequent and abundant. Positive correlations (P less than 0.05) were found between Biomphalaria abundance and some environmental parameters: conductivity, hardness, calcium, nitrites plus nitrates, ammonium and bicarbonates. Water temperature correlation was negative (P less than 0.05). No correlation (P less than 0.05) was found in total iron, phosphates (SRP), pH and soil granulometry. PMID:2134706

  4. Irrigation canals in Melo creek basin (Rio Espera and Capela Nova municipalities, Minas Gerais, Brazil): habitats to Biomphalaria (Gastropoda: Planorbidae) and potential spread of schistosomiasis.

    Science.gov (United States)

    Leite, M G P; Pimenta, E C; Fujaco, M A G; Eskinazi-Sant'Anna, E M

    2016-04-19

    This study analyzed the presence of Biomphalaria in Melo creek basin, Minas Gerais state, and its relationship to irrigation canals. Seventeen of these canals were used to determine a limnological, morphological and hydrological characterization during an annual seasonal cycle. Biomphalaria samples were sent to René Rachou Research Center/FIOCRUZ for identification and parasitological examination. Six canals were identified as breeding areas for mollusks and in one of them it was registered the coexistence of B. tenagophila (first report to this basin) and B. glabrata species. Results indicated that the low flow rate and speed of water flow were the main characteristics that contributed to this specific growth of the mollusks in the area. These hydraulic characteristics were created due to anthropogenic action through the canalization of lotic areas in Melo creek, which allowed ideal ecological conditions to Biomphalaria outbreak. The results emphasize the need of adequate handling and constant monitoring of the hydrographic basin, subject to inadequate phytosanitary conditions, aiming to prevent the occurrence and propagation of schistosomiasis. PMID:27097093

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

    Directory of Open Access Journals (Sweden)

    C Edgardo Borda

    2007-03-01

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

  6. Activity of Polyphenolic Compounds against Candida glabrata

    Directory of Open Access Journals (Sweden)

    Ricardo Salazar-Aranda

    2015-09-01

    Full Text Available Opportunistic mycoses increase the morbidity and mortality of immuno-compromised patients. Five Candida species have been shown to be responsible for 97% of worldwide cases of invasive candidiasis. Resistance of C. glabrata and C. krusei to azoles has been reported, and new, improved antifungal agents are needed. The current study was designed to evaluatethe activity of various polyphenolic compounds against Candida species. Antifungal activity was evaluated following the M27-A3 protocol of the Clinical and Laboratory Standards Institute, and antioxidant activity was determined using the DPPH assay. Myricetin and baicalein inhibited the growth of all species tested. This effect was strongest against C. glabrata, for which the minimum inhibitory concentration (MIC value was lower than that of fluconazole. The MIC values against C. glabrata for myricitrin, luteolin, quercetin, 3-hydroxyflavone, and fisetin were similar to that of fluconazole. The antioxidant activity of all compounds was confirmed, and polyphenolic compounds with antioxidant activity had the greatest activity against C. glabrata. The structure and position of their hydroxyl groups appear to influence their activity against C. glabrata.

  7. Biomphalaria Tenagophila Guaibensis ssp. n. from Southern Brazil and Uruguay (pulmonata: Planorbidae. I. Morphology

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1984-12-01

    Full Text Available A new subspecies of planorbid snail, biomphalaria tenagophila guaibensis, is described. It has been found along the coastal belt of the Brazilian state of rio grande do Sul and the middle part of Uruguay, from Porto Alegre to Mercedes. It differs from the nominate subspecies, Biomphalaria tenagophila tenagophila, in the appearance of the penial complex (prepuce longer and proportionally slenderer in B. t. guaibensis, shorter and proportionally stouter in b. t. tenagophila, in the ratio between the lengths of the penial sheath and the prepuce, in the ratio between the lengths of the uterine complex and the penial complex, and in a coefficient of difference of 2.44 for the ratio between the penis sheath and prepuce and of 2.02 for the ratio between the uterine complex and penial complex. The shell and the other organs of the genital system are similar in both subspecies. B. t. guaibensis is very similar to Biomphalaria occidentalis Paraense, 1981, but is readily separated from it by the presence of a vaginal pouch, which is lacking in the latter, besides showing highly significant difference in the penis sheath: prepuce and uterine complex: penial complex ratios. Crossbreeding experiments which lend additional support to the recognition of B. t. guaibensis as a subspecies will be reported elsewhere.É descrita uma nova subespécie de molusco planorbídeo, Biomphalaria tenagophila guaibensis, que tem sido encontrada ao longo da faixa costeira do Estado do Rio Grande do Sul e da parte média do Uruguai, de Porto Alegre a Mercedes. Distingue-se da espécie nominativa, Biomphalaria tenagophila tenagophila, pelo aspecto do complexo peniano (prepúcio mais longo e proporcionalmente mais delgado em B. t. guaibensis, mais curto e proporcionalmente mais grosso em b. t. tenagophila0, pela razão entre os comprimentos da bainha do pênis e do prepúcio, pela razão entre os comprimentos do complexo uterino e do complexo peniano, e por um coeficiente de

  8. Snail meat: Significance and consumption

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    Dragićević Olgica

    2005-01-01

    Full Text Available The consumption of snail meat goes back to prehistoric times. Different ancient nations had snails on their menu, but Helices culture as a productive activity was born as a Roman culture. Some of the most economically important edible species are: Helix aspersa (Mtiller Helixpomatia (Linne, Helix iucorum (Linne, Helix aperta (Born, Eobania vermiculata (Miiller. Together with its tasie, snail meat has several advantages over others: quite low lipid rate and calorie values versus rich mineral, essential amino acid and fatty acid content. The composition of snail meat is presented. In addition, the composition of different snail species and the part analyzed (pedal mass and visceral mass is presented. Also, the differences in composition according to the species (snail meat horse/chicken meat, beef, swine meat, fish meat are presented. The French are the world's leading consumers of snails. !n France snails come to market in a variety of ways. Estimated consumption of snails in France is around 40 000 tones/year. Total French imports account for 25% of world imports. France is also the leading exporter of prepared snails, mainly sold as preserved snails and prepared dishes. Snail imports have been much higher than exports (65 tones exported in 2002. vs. 2.700 tones imported. Despite the large consumption, only 3% of snails in France come from production (farming. Italy is in second place in the world consumption of snails, and Spain and Germany are in the third and fourth place. The development of snails consumption in Italy is followed with the same amount of production of snails in the whole biological circle. In 2001, from 24,700 tons, 9,350 tons (37.8% came from production, 6 00 tons (2.4% came from nature, and 14,750 tons (59.70% came from imports (frozen, fresh and prepared snails. In Serbia, at the beginning of 2005, we had over 400 registered farms for snail production.

  9. Distribuição de Biomphalaria (Gastropoda, Planorbidae nos Estados do Rio Grande do Sul e Santa Catarina, Brasil The distribution of Biomphalaria (Gastropoda, Planorbidae in Rio Grande do Sul and Santa Catarina States, Brazil

    Directory of Open Access Journals (Sweden)

    Horacio Manuel Santana Teles

    1991-10-01

    Full Text Available É apresentada análise dos conhecimentos sobre a biogeografia das espécies de Biomphalaria transmissoras de Schistosoma mansoni, abrangendo os Estados do Rio Grande do Sul e Santa Catarina (Brasil bem como o relato do encontro de novas localidades colonizadas pelos planorbídeos. Comenta possibilidade da expansão da esquistossomose ao sul do Brasil.An analysis to determine new localities colonized by the intermediate snail hosts (B. straminea, B. tenagophila and B. tenagophila tenagophila of Schistosoma mansoni from Rio Grande do Sul and Santa Catarina States (Brazil was carried out. As regards the geographical distribuition of the schistosomiasis vector, the possible extension of the endemic disease to Southernmost Brazil is commented on.

  10. Potential schistosome-vector snails and associated trematodes in ricefields of Corrients province, Argentina: preliminary results

    Directory of Open Access Journals (Sweden)

    Alejandra Rumi

    1990-09-01

    Full Text Available Considering the possibility of introduction of schistosomiasis mansoni into Argentina as a consequence of dam construction on the Rio De La Plata basin, preliminary studies have been carried out on agrosystems such as ricefields in Corrientes province with the following purposes: 1 to survey and estimate the relative abundance of planorbids and identify potential vector species; 2 to identify environmental factors capable of influencing Biomphalaria population dynamics; and 3 to find out snail-parasite associations and estimate snail infection rates in order to detect possible competitive interactions between larval stages of native trematodes that could be used in biological control of Schistosoma mansoni. Three potential schistosome vectors were detected in ricefields, namely Biomphalaria straminea, B. tenagophila and B. peregrina, although B. orbignyi, a species refractory to infection with S. mansoni, proved the most frequent and abundant. Positive correlations (P0.05 was found in total iron, phosphates (SRP, pH and soil granulometry. Echinocercariae developed from rediae and belonging to Petasiger sp., Paryphostomum sp., and other undetermined species were found.

  11. A Benzoic Acid Derivative and Flavokawains from Piper species as Schistosomiasis Vector Controls

    Directory of Open Access Journals (Sweden)

    Ludmila N. Rapado

    2014-04-01

    Full Text Available The search of alternative compounds to control tropical diseases such as schistosomiasis has pointed to secondary metabolites derived from natural sources. Piper species are candidates in strategies to control the transmission of schistosomiasis due to their production of molluscicidal compounds. A new benzoic acid derivative and three flavokawains from Piper diospyrifolium, P. cumanense and P. gaudichaudianum displayed significant activities against Biomphalaria glabrata snails. Additionally, “in silico” studies were performed using docking assays and Molecular Interaction Fields to evaluate the physical-chemical differences among the compounds in order to characterize the observed activities of the test compounds against Biomphalaria glabrata snails.

  12. Modelling spatial distribution of snails transmitting parasitic worms with importance to human and animal health and analysis of distributional changes in relation to climate

    Directory of Open Access Journals (Sweden)

    Ulrik B. Pedersen

    2014-05-01

    Full Text Available The environment, the on-going global climate change and the ecology of animal species determine the localisation of habitats and the geographical distribution of the various species in nature. The aim of this study was to explore the effects of such changes on snail species not only of interest to naturalists but also of importance to human and animal health. The spatial distribution of freshwater snail intermediate hosts involved in the transmission of schistosomiasis, fascioliasis and paramphistomiasis (i.e. Bulinus globosus, Biomphalaria pfeifferi and Lymnaea natalensis were modelled by the use of a maximum entropy algorithm (Maxent. Two snail observation datasets from Zimbabwe, from 1988 and 2012, were com- pared in terms of geospatial distribution and potential distributional change over this 24-year period investigated. Climate data, from the two years were identified and used in a species distribution modelling framework to produce maps of pre- dicted suitable snail habitats. Having both climate- and snail observation data spaced 24 years in time represent a unique opportunity to evaluate biological response of snails to changes in climate variables. The study shows that snail habitat suit- ability is highly variable in Zimbabwe with foci mainly in the central Highveld but also in areas to the South and West. It is further demonstrated that the spatial distribution of suitable habitats changes with variation in the climatic conditions, and that this parallels that of the predicted climate change.

  13. Environmental epidemiology of intestinal schistosomiasis and genetic diversity of Schistosoma mansoni infections in snails at Bugoigo village, Lake Albert.

    Science.gov (United States)

    Levitz, Sarah; Standley, Claire J; Adriko, Moses; Kabatereine, Narcis B; Stothard, J Russell

    2013-11-01

    Intestinal schistosomiasis continues to be hyper-endemic in the fishing community of Bugoigo located on the eastern shore of Lake Albert, Uganda. Our study aimed to identify the factors that determine the local distribution and abundance of Biomphalaria, as well as infection(s) with Schistosoma mansoni inclusive of their genetic diversity. In addition, a DNA barcoding approach was taken to genotype schistosome cercariae, exploring the micro-epidemiology of infections. Over a 3-week period in June-July 2010, several hundred Biomphalaria spp. were collected, together with environmental information, from 10 selected sites, representative of both putative wave-exposed (n=5) and wave-sheltered shorelines (n=5). A Mann-Whitney U-test and a generalized linear model were used to assess associations with snail abundance and parasite infections across the shoreline. Levels of local wave action were recorded over the 19-day period using digital accelerometers. The general absence of wave action on the sheltered shoreline likely helped to raise and focalize other environmental parameters, such as water conductivity by lack of mixing, that foster transmission of intestinal schistosomiasis. Over the study period, a total of 10 infected snails were encountered and a selection of schistosome cercariae from each infected snail was harvested for analysis by DNA barcoding. In total, 91 DNA barcodes were generated with 15 unique barcode types identified. Of these, 4 barcodes had been found previously in Lake Albert and (or) Victoria, the remaining 11 were newly encountered here and described. The distribution of DNA barcodes across infected snails and sampled locations revealed a complicated spatial sub-structuring. By shedding new light on the fine-scale patterning of infections, DNA barcoding has revealed a rather heterogeneous landscape of cercariae, likely inclusive of multi-miracidial infections within the snail, which will in turn interplay with human water contact activities to

  14. Candida glabrata survives and replicates in human osteoblasts.

    Science.gov (United States)

    Muñoz-Duarte, Ana Rosa; Castrejón-Jiménez, Nayeli Shantal; Baltierra-Uribe, Shantal Lizbeth; Pérez-Rangel, Sofia Judith; Carapia-Minero, Natalee; Castañeda-Sánchez, Jorge Ismael; Luna-Herrera, Julieta; López-Santiago, Rubén; Rodríguez-Tovar, Aída Verónica; García-Pérez, Blanca Estela

    2016-06-01

    Candida glabrata is an opportunistic pathogen that is considered the second most common cause of candidiasis after Candida albicans Many characteristics of its mechanisms of pathogenicity remain unknown. Recent studies have focused on determining the events that underlie interactions between C. glabrata and immune cells, but the relationship between this yeast and osteoblasts has not been studied in detail. The aim of this study was to determine the mechanisms of interaction between human osteoblasts and C. glabrata, and to identify the roles played by some of the molecules that are produced by these cells in response to infection. We show that C. glabrata adheres to and is internalized by human osteoblasts. Adhesion is independent of opsonization, and internalization depends on the rearrangement of the actin cytoskeleton. We show that C. glabrata survives and replicates in osteoblasts and that this intracellular behavior is related to the level of production of nitric oxide and reactive oxygen species. Opsonized C. glabrata stimulates the production of IL-6, IL-8 and MCP-1 cytokines. Adhesion and internalization of the pathogen and the innate immune response of osteoblasts require viable C. glabrata These results suggest that C. glabrata modulates immunological mechanisms in osteoblasts to survive inside the cell. PMID:27073253

  15. Dispersão de Biomphalaria straminea, hospedeira intermediária do Schistosoma mansoni, através da distribuição de peixes The spreading of Biomphalaria straminea, intermediate host of Schistosoma mansoni through the distribution of fishes

    Directory of Open Access Journals (Sweden)

    Renato de R. Corrêa

    1970-12-01

    Full Text Available Foi focalizado, pela primeira vez o encontro de B. straminea no Estado de São Paulo. Esta espécie vem juntar-se aos planorbídeos já assinalados em nosso Estado. Foram descritos os criadouros, onde a B. straminea foi coletada, localizados em tanques de criação de peixes nas Estações de Piscicultura de Barra Bonita e Americana, Estado de São Paulo, e em um aquário particular na capital dêsse Estado. Fêz-se referência ao transporte de peixes oriundos de zonas do país onde ocorre aquela espécie, Amazonas e Ceará, como responsável pela introdução daquele molusco no Estado. Destacou-se êsse achado pelo perigo que representa a distribuição de peixes da maneira como vem sendo feita atualmente em nosso país, tendo sido julgado necessário o estabelecimento de quarentena para aquêles vindos de zonas infestadas por espécies hospedeiras intermediárias do S. mansoni. Foram relatadas as medidas de combate aos caramujos efetuadas imediatamente após aquela descoberta e os resultados obtidos. Conclui-se que a dispersão passiva da B. straminea pelo transporte de peixes, deve ampliar a distribuição geográfica dêsse planorbídeo, já assinalado na Venezuela, Guianas e no Brasil, sendo que neste último ocorre em tôdas as Unidades Federativas, exceto, no Rio Grande do Sul, Santa Catarina, Rio de Janeiro e Territórios.Up the present, the works of collecting planorbids done in 226 municipalities for the elaboration of the geographical distribution chart in the State of São Paulo (Brazil, showed the presence of two intermediate host species of Schistosoma mansoni: Biomphalaria tenagophila and Biompralaria glabrata. Although the technicians from the Psiculture Stations, have not found snails in the water inside the containers used for the transportation of fishes, the ecological conditions of B. straminea in the latest researches are such as to indicate that they have been introduced, in our State through fish transportation imported

  16. 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...

  17. Crescimento de órgãos do aparelho reprodutor durante o desenvolvimento de Biomphalaria tenagophila (Orbigny (Mollusca, Planorbidae

    Directory of Open Access Journals (Sweden)

    MONTEIRO W.

    1998-01-01

    Full Text Available Biomphalaria tenagophila é um hermafrodita simultâneo cujo investimento na função masculina foi avaliado pelo crescimento de seus órgãos sexuais em relação ao diâmetro da concha. Foram criadas novas técnicas para medir órgãos reprodutivos, sem aparentes distorções, e contar folículos do ovoteste. Durante o crescimento de espécimes sexualmente maduros de B. tenagophila, cresceu o número de folículos do ovoteste, mas seus números máximos e mínimos são menores do que os citados na literatura. O número de divertículos da próstata e de folículos do ovoteste de B. glabrata é maior do que o de B. tenagophila. Embora o comprimento do ovoteste, da próstata, da bainha do pênis e da glândula mucípara-ootecal variassem durante o crescimento do caramujo, não variou significativamente o número de divertículos da próstata.

  18. Candida glabrata infection following total hip arthroplasty: A case report

    OpenAIRE

    Zhu, Yun; Yue, Chen; Huang, Zeyu; Pei, Fuxing

    2013-01-01

    Candida glabrata infection following total hip arthroplasty is rare and, due to the insufficiency of standardized clinical and evidence-based guidelines, there is no appropriate therapeutic schedule. The present study reports the case of a 44-year-old patient with Candida glabrata infection following a total hip arthroplasty. The patient was successfully treated by administration of intravenous and oral voriconazole without removal of the prosthesis. This case illustrates the significance of ...

  19. An artificial perch to help Snail Kites handle an exotic Apple Snail

    Science.gov (United States)

    Pias, Kyle E.; Welch, Zach C.; Kitchens, Wiley M.

    2012-01-01

    In the United States, the Snail Kite (Rostrhamus sociabilis plumbeus) is a federally endangered species and restricted to the wetlands of south-central Florida where the current population numbers less than 1,500. The Snail Kite is an extreme dietary specialist, previously feeding almost exclusively on one species of snail, the Florida Apple Snail (Pomacea paludosa). Within the past decade, an exotic species of apple snail, the Island Apple Snail (Pomacea insularum), has become established on lakes in central Florida. Island Apple Snails are larger than the native Florida Apple Snails, and Snail Kites handle the exotic snails less efficiently. Juvenile Snail Kites, in particular, have lower daily energy balances while feeding on Island Apple Snails. An inexpensive, easy-to-construct platform was developed that would provide Snail Kites with a flat, stable surface on which to extract snails. The platform has the potential to reduce the difficulties Snail Kites experience when handling exotic snails, and may benefit the Snail Kite population as a whole. Initial observations indicate that Snail Kites use the platforms frequently, and snails extracted at the platforms are larger than snails extracted at other perches.

  20. Molluscicidal saponins from Phytolacca dodecandra

    DEFF Research Database (Denmark)

    Thiilborg, S. T.; Christensen, S. B.; Cornett, Claus;

    1993-01-01

    -beta-D-xylopyranosyl-(1-->6)-O-beta-D-gluco-pyranosyl-(1-->3)]-beta -D-glucopyranosyloleanolic acid mainly by spectroscopic methods (LSIMS, H-1 NMR, COSY, NOESY, TOCSY, J-resolved H-1 NMR, C-13 NMR, HETCOR). The saponins are potent molluscicides against the schistosomiasis transmitting snail Biomphalaria glabrata with LC...

  1. 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.

  2. 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.

  3. Biomphalaria prona (Gastropoda: Planorbidae: a morphological and biochemical study

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1992-06-01

    Full Text Available Two samples of Biomphalaria prona (Martens, 1873 from Lake Valencia (type locality and seven from other Venezuelan localities were studied morphologically (shell and reproductive system and biochemically (allozyme electrophoresis. In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacustrine populations refered to Biomphalaria havanensis (Pfeiffer, 1839 by several authors correspond in shell characters to an extreme variant of B. prona from the Lake and really belong to the last*mentioned species. They may be regarded as the result of a process of directional selection favoring a shell phenotype other than those making up the modal class in the Lake.

  4. Biomphalaria prona (Gastropoda: Planorbidae): a morphological and biochemical study

    OpenAIRE

    W. Lobato Paraense; Pointier, J.P.; Delay, B.; A. F. Pernot; Incani, R N; C. Balzan; P. Chrosciechowski

    1992-01-01

    Two samples of Biomphalaria prona (Martens, 1873) from Lake Valencia (type locality) and seven from other Venezuelan localities were studied morphologically (shell and reproductive system) and biochemically (allozyme electrophoresis). In spite of marked differences in shell characters, all of them proved indistinguishable under the anatomic and biochemical criteria. So far B. prona has been considered an endemic species, restricted to Lake Valencia. It is now demonstrated that the extralacust...

  5. Diversity and antifungal susceptibility of Norwegian Candida glabrata clinical isolates

    Science.gov (United States)

    Andersen, Kari-Mette; Kristoffersen, Anne Karin; Ingebretsen, André; Vikholt, Katharina Johnsen; Örtengren, Ulf Thore; Olsen, Ingar; Enersen, Morten; Gaustad, Peter

    2016-01-01

    Background Increasing numbers of immunocompromised patients have resulted in greater incidence of invasive fungal infections with high mortality. Candida albicans infections dominate, but during the last decade, Candida glabrata has become the second highest cause of candidemia in the United States and Northern Europe. Reliable and early diagnosis, together with appropriate choice of antifungal treatment, is needed to combat these challenging infections. Objectives To confirm the identity of 183 Candida glabrata isolates from different human body sites using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and VITEK®2, and to analyze isolate protein profiles and antifungal susceptibility. The minimum inhibitory concentration (MIC) of seven antifungal drugs was determined for the isolates to elucidate susceptibility. Design A total of 183 C. glabrata isolates obtained between 2002 and 2012 from Norwegian health-care units were analyzed. For species verification and differentiation, biochemical characterization (VITEK®2) and mass spectrometry (MALDI–TOF) were used. MIC determination for seven antifungal drugs was undertaken using E-tests®. Results Using VITEK®2, 92.9% of isolates were identified as C. glabrata, while all isolates (100%) were identified as C. glabrata using MALDI-TOF. Variation in protein spectra occurred for all identified C. glabrata isolates. The majority of isolates had low MICs to amphotericin B (≤1 mg/L for 99.5%) and anidulafungin (≤0.06 mg/L for 98.9%). For fluconazole, 18% of isolates had MICs >32 mg/L and 82% had MICs in the range ≥0.016 mg/L to ≤32 mg/L. Conclusions Protein profiles and antifungal susceptibility characteristics of the C. glabrata isolates were diverse. Clustering of protein profiles indicated that many azole resistant isolates were closely related. In most cases, isolates had highest susceptibility to amphotericin B and anidulafungin. The results confirmed previous observations of high

  6. A family of fibrinogen-related proteins that precipitates parasite-derived molecules is produced by an invertebrate after infection

    OpenAIRE

    Adema, Coen M.; Lynn A Hertel; Miller, Robert D.; Eric S Loker

    1997-01-01

    After infection with the digenetic trematode Echinostoma paraensei, hemolymph of the snail Biomphalaria glabrata contains lectins comprised of 65-kDa subunits that precipitate polypeptides secreted by E. paraensei intramolluscan larvae. Comparable activity is lacking in hemolymph of uninfected snails. Three different cDNAs with sequence similarities to peptides derived from the 65-kDa lectins were obtained and unexpectedly found to encode fibrinogen-related proteins (FREPs). These FREPs also ...

  7. The ecology of Bulinus truncatus and Biomphalaria alexandrina and its implications for the control of bilharziasis in the Egypt-49 project area.

    Science.gov (United States)

    Dazo, B C; Hairston, N G; Dawood, I K

    1966-01-01

    The respective vectors of the two forms of bilharziasis in Egypt do not have the same ecological distribution. Bulinus truncatus is most abundant in large canals, and decreases in density as the water approaches and flows into drains. Biomphalaria alexandrina is most abundant in drains, and decreases in density upstream from these habitats. Both species are most abundant in the presence of aquatic vegetation, but they differ in their respective associations with the water hyacinth, Eichhornia crassipes. Biomph. alexandrina reaches maximum abundance in the presence of this plant, but Bul. truncatus is as uncommon in the absence of plants as in the presence of E. crassipes.Calculation of life-table parameters from field data shows that, under optimum field conditions, both species can double their populations in 14-16 days. The reproductive rates of both species are greatest in March and the death rates in midsummer. The observed peak densities in May and June give a false impression of optima because of undercollection of young snails, which are most abundant in March and April.Control operations should take advantage of the findings on population parameters. A single area-wide treatment with molluscicide in April is recommended. During the remainder of the year, search for isolated foci of snail breeding and individual treatment of these will effect large savings of chemical and will be effective in controlling the transmission of the parasites. PMID:5297630

  8. A malacological survey in the Manso Power Plant, State of Mato Grosso, Brazil: new records of freshwater snails, including transmitters of schistosomiasis and exotic species

    Directory of Open Access Journals (Sweden)

    Monica Ammon Fernandez

    2014-07-01

    Full Text Available Introduction Schistosomiasis is a parasitic disease of public health concern in Brazil, and the construction of hydroelectric dams, in addition to increasing permanent human settlement and tourism, has created conditions suitable for the establishment of mollusks that can transmit schistosomiasis. Such areas require a number of actions to prevent the establishment of schistosomiasis. This paper reports on a freshwater malacological survey carried out in the geographical area of the Manso Power Plant. Methods Mollusks were collected in 18 municipalities in the State of Mato Grosso between February 2002 and February 2004 (qualitative study and from April 2009 to February 2011 (quantitative study. Results Thirty-one species of mollusks were collected, including newly recorded species (Antillorbis nordestensis and Burnupia ingae. In addition, the geographic distributions of known species, including Biomphalaria straminea, a snail vector of Schistosoma mansoni, were expanded. A total of 4,507 specimens were collected in the APM Manso reservoir (Usina Hidrelétrica de Aproveitamento Múltiplo de Manso during the quantitative study, and Biomphalaria amazonica was found in six of the 10 localities analyzed. The Afroasiatic species Melanoides tuberculata, introduced after February 2009, was the dominant species (relative abundance 94.96%. Conclusions The study area is epidemiologically important due to the occurrence of B. straminea and B. amazonica, which are vectors of schistosomiasis, and M. tuberculata, a snail host of Centrocestus formosanus, which is responsible for centrocestiasis transmission. Observations of M. tuberculata and the exotic freshwater clams Corbicula fluminea and Corbicula largillierti raise concerns about biodiversity.

  9. Morphological and polymerase chain reaction-restriction fragment lenght polymorphism characterization of Biomphalaria kuhniana and Biomphalaria amazonica from Colombia

    Directory of Open Access Journals (Sweden)

    Luz E Velásquez

    2002-10-01

    Full Text Available In Colombia, five Biomphalaria planorbid species are known: B. kuhniana, B. straminea, B. peregrina, B. canonica and B. oligoza(var. B. philippiana. Among them, B. straminea is intermediate host of Schistosoma mansoni and B. peregrina has been found to be experimentally susceptible to this parasite. B. straminea is commonly confused with B. kuhniana and they have been clustered together with B. intermedia in the complex named B. straminea. The difficulties involved in the specific identification, based on morphological data, have motivated the use of new techniques as auxiliary tools in cases of inconclusive morphological identification of such planorbid. In the present study, five Biomphalaria populations from the Colombian Amazon region and from Interandian Valleys were morphologically identified and characterized by polymerase chain reaction-restriction fragment lenght polymorphism directed at the internal transcribed spacer region of the rRNA gene, followed by digestion of the generated fragment with restriction enzymes (DdeI, AluI, RsaI, MvaI and HaeIII. Known profiles of the Brazilian species B. straminea, B. peregrina, B. kuhniana, B. intermedia and B. amazonica, besides B. kuhniana from Colombia, were used for comparison. The five populations under study were morphologically and molecularly identified as B. kuhniana and B. amazonica.

  10. Candida glabrata : a review of its features and resistance

    OpenAIRE

    Rodrigues, Célia F.; Silva, Sónia Carina; Henriques, Mariana

    2014-01-01

    Candida species belong to the normal microbiota of the oral cavity and gastrointestinal and vaginal tracts, and are responsible for several clinical manifestations, from mucocutaneous overgrowth to bloodstream infections. Once believed to be non-pathogenic, Candida glabrata was rapidly blamable for many human diseases. Year after year, these pathological circumstances are more recurrent and problematic to treat, especially when patients reveal any level of immunosuppression. These difficultie...

  11. Candida glabrata: Review of Epidemiology, Pathogenesis, and Clinical Disease with Comparison to C. albicans

    OpenAIRE

    Fidel, Paul L.; Jose A. Vazquez; Sobel, Jack D

    1999-01-01

    Until recently, Candida glabrata was considered a relatively nonpathogenic commensal fungal organism of human mucosal tissues. However, with the increased use of immunosuppressive agents, mucosal and systemic infections caused by C. glabrata have increased significantly, especially in the human immunodeficiency virus-infected population. A major obstacle in C. glabrata infections is their innate resistance to azole antimycotic therapy, which is very effective in treating infections caused by ...

  12. Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

    Directory of Open Access Journals (Sweden)

    Carmen Fuentealba

    2012-11-01

    Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp

  13. The Snail Takes a Walk with Me

    Institute of Scientific and Technical Information of China (English)

    王宜鸣; 乐伟国

    2008-01-01

    @@ 一、故事内容 I'm a snake. Today God gives me a job-I should take a walk with the snail. The snail moves too slowly. I have to scare him. He looks at me, full of shame. I am very angry. I pull him, and even kick.The snail cries, so he stops walking. I feel quite helpless.

  14. Snail modulates cell metabolism in MDCK cells

    International Nuclear Information System (INIS)

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O2 consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP+-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of key enzymes

  15. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  16. Celss nutrition system utilizing snails

    Science.gov (United States)

    Midorikawa, Y.; Fujii, T.; Ohira, A.; Nitta, K.

    At the 40th IAF Congress in Malaga, a nutrition system for a lunar base CELSS was presented. A lunar base with a total of eight crew members was envisaged. In this paper, four species of plants—rice, soybean, lettuce and strawberry—were introduced to the system. These plants were sufficient to satisfy fundamental nutritional needs of the crew members. The supply of nutrition from plants and the human nutritional requirements could almost be balanced. Our study revealed that the necessary plant cultivation area per crew member would be nearly 40 m 3 in the lunar base. The sources of nutrition considered in the study were energy, sugar, fat, amino acids, inorganic salt and vitamins; however, calcium, vitamin B 2, vitamin A and sodium were found to be lacking. Therefore, a subsystem to supply these elements is of considerable value. In this paper, we report on a study for breeding snails and utilizing meat as food. Nutrients supplied from snails are shown to compensate for the abovementioned lacking elements. We evaluate the snail breeder and the associated food supply system as a subsystem of closed ecological life support system.

  17. Characterization of the Life Cycle of a Fish Eye Fluke, Austrodiplostomum ostrowskiae (Digenea: Diplostomidae), with Notes on Two Other Diplostomids Infecting Biomphalaria havanensis (Mollusca: Planorbidae) from Catfish Aquaculture Ponds in Mississippi, USA.

    Science.gov (United States)

    Rosser, Thomas G; Alberson, Neely R; Khoo, Lester H; Woodyard, Ethan T; Pote, Linda M; Griffin, Matt J

    2016-04-01

    Ocular diplostomiasis is caused by trematode species in the family Diplostomidae, specifically those in the genera Austrodiplostomum, Diplostomum, and Tylodelphys. Diplostomid trematodes are globally distributed parasites of fish. Heavy infections of diplostomids that parasitize the eyes of fish can result in acute mortality while chronic infections are often characterized by impaired vision or blindness. In the southeastern United States, commercial catfish production is threatened by piscivorous birds and the many trematode species that parasitize them. The life cycles typically involve a piscivorous avian definitive host, a mollusk first intermediate host, and a fish second intermediate host. A survey of parasites infecting the snail host Biomphalaria havanensis (= B. obstructa ) in catfish production ponds was undertaken. Snails were collected from 2 separate ponds during the summer of 2014 and observed for the release of trematode cercariae. A total of 1,740 snails were collected. Three distinct longifurcate pharyngeate cercariae were observed and these cercariae were characterized morphologically and molecularly. Sequencing of ∼4,200 base pairs (bp) of the nuclear ribosomal genes and ∼450 bp of the mitochondrial cytochrome c oxidase gene revealed 3 genetically distinct species. One morphotype shared 99-100% sequence identity with metacercariae from the aqueous and vitreous humors of gizzard shad Dorosoma cepedianum and channel catfish Ictalurus punctatus as well as an adult trematode, Austrodiplostomum ostrowskiae, a parasite of the double-crested cormorant Nannopterum auritus. The remaining 2 cercariae morphotypes shared 99-100% sequence identity with an unidentified Tylodelphys sp. and Austrodiplostomum sp. metacercaria from the brain and eyes of several freshwater fish. Herein we molecularly link the cercaria, metacercaria, and adult stage of the life cycle of A. ostrowskiae, identifying the snail host for this parasite, in addition to providing notes

  18. Production of apple snail for space diet

    Science.gov (United States)

    Yamashita, Masamichi; Motoki, Shigeru; Space Agriculture Task Force, J.; Katayama, Naomi

    For food production in space at recycling bio-elements under closed environment, appropriate organisms should be chosen to drive the closed materials recycle loop. We propose a combination of green algae, photosynthetic protozoa, and aquatic plants such as Wolffia spp., for the primary producer fixing solar energy to chemical form in biomass, and apple snail, Pomacea bridgesii, which converts this biomass to animal meat. Because of high proliferation rate of green algae or protozoa compared to higher plants, and direct conversion of them to apple snail, the efficiency of food production in this combination is high, in terms of energy usage, space for rearing, and yield of edible biomass. Furthermore, green algae and apple snail can form a closed ecological system with exchanging bio-elements between two member, i.e. excreta of snail turn to fertilizer of algae, and grown algae become feed for snail. Since apple snail stays in water or on wet substrate, control of rearing is easy to make. Mass production technology of apple snail has been well established to utilize it as human food. Nutrients of apple snail are also listed in the standard tables of food composition in Japan. Nutrients for 100 g of apple snail canned in brine are energy 340 kJ, protein 16.5 g, lipid 1.0 g, cholesterol 240 mg, carbohydrate 0.8 g, Ca 400 mg, Fe 3.9 mg, Zn 1.5 mg. It is rich in minerals, especially Ca and Fe. Vitamin contents are quite low, but K 0.005 mg, B2 0.09 mg, B12 0.0006 mg, folate 0.001 mg, and E 0.6 mg. The amino acid score of apple snail could not be found in literature. Overall, apple snail provides rich protein and animal lipid such as cholesterol. It could be a good source of minerals. However, it does not give enough vitamin D and B12 , which are supposed to be supplemented by animal origin foods. In terms of acceptance in food culture, escargot is a gourmet menu in French dishes, and six to ten snail, roughly 50 g, are served for one person. Apple snail reaches to 30 g

  19. The Drosophila Toll pathway controls but does not clear Candida glabrata infections.

    Science.gov (United States)

    Quintin, Jessica; Asmar, Joelle; Matskevich, Alexey A; Lafarge, Marie-Céline; Ferrandon, Dominique

    2013-03-15

    The pathogenicity of Candida glabrata to patients remains poorly understood for lack of convenient animal models to screen large numbers of mutants for altered virulence. In this study, we explore the minihost model Drosophila melanogaster from the dual perspective of host and pathogen. As in vertebrates, wild-type flies contain C. glabrata systemic infections yet are unable to kill the injected yeasts. As for other fungal infections in Drosophila, the Toll pathway restrains C. glabrata proliferation. Persistent C. glabrata yeasts in wild-type flies do not appear to be able to take shelter in hemocytes from the action of the Toll pathway, the effectors of which remain to be identified. Toll pathway mutant flies succumb to injected C. glabrata. In this immunosuppressed background, cellular defenses provide a residual level of protection. Although both the Gram-negative binding protein 3 pattern recognition receptor and the Persephone protease-dependent detection pathway are required for Toll pathway activation by C. glabrata, only GNBP3, and not psh mutants, are susceptible to the infection. Both Candida albicans and C. glabrata are restrained by the Toll pathway, yet the comparative study of phenoloxidase activation reveals a differential activity of the Toll pathway against these two fungal pathogens. Finally, we establish that the high-osmolarity glycerol pathway and yapsins are required for virulence of C. glabrata in this model. Unexpectedly, yapsins do not appear to be required to counteract the cellular immune response but are needed for the colonization of the wild-type host. PMID:23401590

  20. Molluscicide control of snail vectors of schistosomiasis

    Directory of Open Access Journals (Sweden)

    Cecília Pereira de Souza

    1995-04-01

    Full Text Available A review of the methodology recommended by the World Health Organization for the use of molluscicides for the control of snail vectors of schistosomiasis is presented. Discussion of the principle molluscicides used, their advantages and disadvantages, the techniques and equipment required for their application and evaluation of effect as well as the biological control of snails is included.

  1. Molluscicide control of snail vectors of schistosomiasis

    OpenAIRE

    Cecília Pereira de Souza

    1995-01-01

    A review of the methodology recommended by the World Health Organization for the use of molluscicides for the control of snail vectors of schistosomiasis is presented. Discussion of the principle molluscicides used, their advantages and disadvantages, the techniques and equipment required for their application and evaluation of effect as well as the biological control of snails is included.

  2. Structure-Guided Development of Efficacious Antifungal Agents Targeting Candida Glabrata Dihydrofolate Reductase

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Bolstad, D; Smith, A; Priestley, N; Wright, D; Anderson, A

    2008-01-01

    Candida glabrata is a lethal fungal pathogen resistant to many antifungal agents and has emerged as a critical target for drug discovery. Over the past several years, we have been developing a class of propargyl-linked antifolates as antimicrobials and hypothesized that these compounds could be effective inhibitors of dihydrofolate reductase (DHFR) from C. glabrata. We initially screened a small collection of these inhibitors and found modest levels of potency. Subsequently, we determined the crystal structure of C. glabrata DHFR bound to a representative inhibitor with data to 1.6 A resolution. Using this structure, we designed and synthesized second-generation inhibitors. These inhibitors bind the C. glabrata DHFR enzyme with subnanomolar potency, display greater than 2000-fold levels of selectivity over the human enzyme, and inhibit the growth of C. glabrata at levels observed with clinically employed therapeutics.

  3. Current Situation of Edible Snails in Indonesia

    Directory of Open Access Journals (Sweden)

    Schneider, K.

    1999-01-01

    Full Text Available From March 7, 1995 to April 16, 1995 du ring the rainy season the utilisation of edible snails was investigated in Indonesia. To assess the current situation, the focus was put to answer the following questions : - Is it feasible under the present circumstances to domesticate these snails with the aim to conserve the natural resources ? - Could any individual or private initiative be enhanced or utilized ? - Would local disadvantaged groups (traditional animal farmers, women oryouths be benefitted through domestication of these snails ? - Is there any existing private organisation or NGO, which already gathers and trades the snails or would be interested to do this in the future ? Snails gatherers, -dealers and -farmers were visited and interviewed on the following topics using standardised questionnaires : Spreading and ecology ways of marketing, consumption habits, breeding and rearing. Diotopes were also visited and investigated. Results Spreading and ecology : Achatina fulica, Pomacea canaliculata, Pila ampullacea and Bellamia javanica are eaten. The snails can be found ail overJava. Ways of marketing : The snails gathered in the biotope are either marketed directly or through various marketing paths. A. fulica is exported in large quantifies. The population is therefore endangered. Consumption habits : Snails are not eaten regularly. Snail meat is known to be healthy. The consumption depends on the consumer's ethnie background. Breeding and rearing experience : with simple breeding systems for A. fulica and P. canaliculata are seldom found. The breeding of P. canaliculata is forbidden in Indonesia. There is no interest in breeding P. ampullacea or B. javanica. The breeding of A. fulica can ben-efit disadvantaged groups financially and help to conserving the natural snail population.

  4. Criação de caramujos infectados para obtenção em massa de cercárias e esquistossômulos Rearing of infected snails for mass production of cercariae and schistossomula

    OpenAIRE

    Cecília Pereira de Souza; Giovanni Gazzinelli; Neusa Araújo; Otávio Francisco Rosa Cruz; Carlos Rubens Teixeira da Silva

    1985-01-01

    O sistema por nós utilizado para manutenção de moluscos infectados, Biomphalaria glabrata, capaz de produzir de 1-2 milhões de cercárias por semana, foi analisado quantitativamente. A produção média foi da ordem de 3.500 cercárias/molusco, com diminuição acentuada nos meses de novembro e dezembro de 1982 e 1983, relacionada com picos de elevação de temperatura e com a presença de rotíferos nos aquários. Para uma produção mensal em 1982 e 1983 de 5,3 e 6,5 milhões de cercárias, respectivamente...

  5. An example of molecular co-evolution: Reactive oxygen species (ROS) and ROS scavenger levels in Schistosoma mansoni/Biomphalaria glabrata interactions.

    OpenAIRE

    Moné, Yves; Ribou, Anne-Cécile; Cosseau, Céline; Duval, David; Théron, André; Mitta, Guillaume; Gourbal, Benjamin

    2011-01-01

    The co-evolution between hosts and parasites involves huge reciprocal selective pressures on both protagonists. However, relatively few reports have evaluated the impact of these reciprocal pressures on the molecular determinants at the core of the relevant interaction, such as the factors influencing parasitic virulence and host resistance. Here, we address this question in a host-parasite model that allows co-evolution to be monitored in the field: the interaction between the mollusc, Biomp...

  6. Pathogenesis and Antifungal Drug Resistance of the Human Fungal Pathogen Candida glabrata

    Directory of Open Access Journals (Sweden)

    Karl Kuchler

    2011-01-01

    Full Text Available Candida glabrata is a major opportunistic human fungal pathogen causing superficial as well as systemic infections in immunocompromised individuals and several other patient cohorts. C. glabrata represents the second most prevalent cause of candidemia and a better understanding of its virulence and drug resistance mechanisms is thus of high medical relevance. In contrast to the diploid dimorphic pathogen C. albicans, whose ability to undergo filamentation is considered a major virulence trait, C. glabrata has a haploid genome and lacks the ability to switch to filamentous growth. A major impediment for the clinical therapy of C. glabrata infections is its high intrinsic resistance to several antifungal drugs, especially azoles. Further, the development of antifungal resistance, particularly during prolonged and prophylactic therapies is diminishing efficacies of therapeutic interventions. In addition, C. glabrata harbors a large repertoire of adhesins involved in the adherence to host epithelia. Interestingly, genome plasticity, phenotypic switching or the remarkable ability to persist and survive inside host immune cells further contribute to the pathogenicity of C. glabrata. In this comprehensive review, we want to emphasize and discuss the mechanisms underlying virulence and drug resistance of C. glabrata, and discuss its ability to escape from the host immune surveillance or persist inside host cells.

  7. Iron-depletion promotes mitophagy to maintain mitochondrial integrity in pathogenic yeast Candida glabrata

    Science.gov (United States)

    Nagi, Minoru; Tanabe, Koichi; Nakayama, Hironobu; Ueno, Keigo; Yamagoe, Satoshi; Umeyama, Takashi; Ohno, Hideaki; Miyazaki, Yoshitsugu

    2016-01-01

    ABSTRACT Candida glabrata, a haploid budding yeast, is the cause of severe systemic infections in immune-compromised hosts. The amount of free iron supplied to C. glabrata cells during systemic infections is severely limited by iron-chelating proteins such as transferrin. Thus, the iron-deficiency response in C. glabrata cells is thought to play important roles in their survival inside the host's body. In this study, we found that mitophagy was induced under iron-depleted conditions, and that the disruption of a gene homologous to ATG32, which is responsible for mitophagy in Saccharomyces cerevisiae, blocked mitophagy in C. glabrata. The mitophagic activity in C. glabrata cells was not detected on short-period exposure to nitrogen-starved conditions, which is a mitophagy-inducing condition used in S. cerevisiae. The mitophagy-deficient atg32Δ mutant of C. glabrata also exhibited decreased longevity under iron-deficient conditions. The mitochondrial membrane potential in Cgatg32Δ cells was significantly lower than that in wild-type cells under iron-depleted conditions. In a mouse model of disseminated infection, the Cgatg32Δ strain resulted in significantly decreased kidney and spleen fungal burdens compared with the wild-type strain. These results indicate that mitophagy in C. glabrata occurs in an iron-poor host tissue environment, and it may contribute to the longevity of cells, mitochondrial quality control, and pathogenesis. PMID:27347716

  8. Candida glabrata Esophagitis: Are We Seeing the Emergence of a New Azole-Resistant Pathogen?

    Directory of Open Access Journals (Sweden)

    Aze Wilson

    2014-01-01

    Full Text Available Background. Candida glabrata (C. glabrata has become a recognized pathogen in fungal esophagitis. A proportion of these isolates are azole-resistant which may have treatment implications. Variability in the prevalence of this organism exists in the limited data available. Objective. To determine the incidence of C. glabrata esophagitis in a North American hospital setting and to highlight factors that may predispose patients to this condition. Methods. Patient charts were collected from January 1, 2009 to July 30, 2011. Any charts of patients identified as having esophagitis with a positive fungal culture were reviewed for the species of Candida and the presence of factors that would predispose them to esophageal candidiasis. Results. The prevalence of Candida esophagitis based on culture was 2.2% (37 subjects. C. glabrata was the 2nd most prevalent pathogen identified (24.3% or 9 subjects. Of the C. glabrata cohort, all patients had at least one factor predisposing them to candidiasis. Conclusion. C. glabrata esophagitis makes up a large portion of the candidal esophagitis seen in hospital. C. glabrata infections were associated with at least one risk factor for candidal infection. Given its resistance to azole-based therapy, this may have treatment implications for how candidal esophagitis is approached by the clinician.

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

    Science.gov (United States)

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

    2007-12-01

    The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails. PMID:18383803

  10. Evaluation of the molluscicidal properties of Euphorbia splendens var. hislopii (n. e. b.) (Euphorbiaceae) - 1: experimental test in a lentic habitat

    OpenAIRE

    Nelymar Martineli Mendes; Darcilio Fernandes Baptista; Maurício Carvalho Vasconcellos; Virgínia Torres Schall

    1992-01-01

    The latex of Euphorbia splendens var. hislopii, at concentrations between 5 to 12 mg/l, kills 100% of the population of Biomphalaria glabrata in a lentic habitat, after 24 h. The lyophilized latex, stocked for 18 months, killed only 34.2% of the snails, at the concentration of 5 mg/l, and 96.0% at 12 mg/l. No lethal effect was observed among Pomacea haustrum exposed to the same concentrations of the molluscicide.

  11. Evaluation of the toxicity and molluscicidal and larvicidal activities of Schinopsis brasiliensis stem bark extract and its fractions

    OpenAIRE

    Clisiane C.S. Santos; Silvan S. Araújo; André L. L. M. Santos; Elis C.V. Almeida; Antônio S. Dias; Nicole P. Damascena; Deisylaine M. Santos; Matheus I.S. Santos; Karlos A.L.R. Júnior; Carla K. B. Pereira; Amanda C.B. Lima; Andrea Y.K.V. Shan; Antônio E. G. Sant'Ana; Charles S. Estevam; Brancilene S. de Araujo

    2014-01-01

    Dengue fever and schistosomiasis are major public health issues for which vector control using larvicide and molluscicide substances present in plants provides a promising strategy. This study evaluated the potential toxicity of the extract of hydroethanol Schinopsis brasiliensis Engl., Anacardiaceae, stem bark and its chloroform, hexane, ethyl acetate, and hydromethanol fractions against Artemia salina and Aedes Aegypti larvae and snails Biomphalaria glabrata. All of the assays were performe...

  12. Evaluation of the molluscicidal properties of Euphorbia splendens var. hislopii (n. e. b. (Euphorbiaceae - 1: experimental test in a lentic habitat

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1992-03-01

    Full Text Available The latex of Euphorbia splendens var. hislopii, at concentrations between 5 to 12 mg/l, kills 100% of the population of Biomphalaria glabrata in a lentic habitat, after 24 h. The lyophilized latex, stocked for 18 months, killed only 34.2% of the snails, at the concentration of 5 mg/l, and 96.0% at 12 mg/l. No lethal effect was observed among Pomacea haustrum exposed to the same concentrations of the molluscicide.

  13. The Holozoan Capsaspora owczarzaki Possesses a Diverse Complement of Active Transposable Element Families

    OpenAIRE

    Carr, Martin; Suga, Hiroshi

    2014-01-01

    Capsaspora owczarzaki, a protistan symbiont of the pulmonate snail Biomphalaria glabrata, is the centre of much interest in evolutionary biology due to its close relationship to Metazoa. The whole genome sequence of this protist has revealed new insights into the ancestral genome composition of Metazoa, in particular with regard to gene families involved in the evolution of multicellularity. The draft genome revealed the presence of 23 families of transposable element, made up from DNA transp...

  14. Molluscicidal activity of crown of Christ (Euphorbia splendens var. hislopii) (Euphorbiaceae) latex submitted to pH variation

    OpenAIRE

    Vasconcellos Maurício Carvalho de; Santos José Augusto Albuquerque dos; Silva Ivonise Paz da; Lopes Fátima Eliana Ferreira; Schall Virgínia Torres

    2003-01-01

    Laboratory and field bioassays have confirmed the specificity of the molluscicidal activity of the Euphorbia splendens var. hislopii latex (crown of Christ) (Euphorbiaceae) over snails of the species Biomphalaria glabrata, B. tenagophila, B. straminea, B. pfeifferi and Bulinus sp. in the control of Schistosoma mansoni. In the present study, the effect of the pH variation on lethal concentration (LC90) over B. tenagophila was evaluated. Bioassays with the aqueous solutions of the latex ranging...

  15. CRCP-Prey choice of corallivorous snails

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The snail, Coralliophila abbreviata, is a common generalist corallivore and can be a major contributor to Caribbean acroporid tissue mortality. Considering the...

  16. Status report on Fish Springs pond snail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides a life history of the pond snail (Lymnaea Hinkleyia pilsbryi) at Fish Springs National Wildlife Refuge. The following information is included;...

  17. Freshwater snail consumption and angiostrongyliasis in Malaya.

    Science.gov (United States)

    Liat, L B; Fong, Y L; Krishnansamy, M; Ramachandran, P; Mansor, S

    1978-06-01

    A survey of the freshwater snails, Pila scutata and Bellamyia ingallsiana, as food consumed by the local population was carried out in Peninsular Malaysia. Of these two species the first is preferred; the sizes favoured are between 25--40 mm. Pila snails were found to be consumed by the three communities, viz. Malay, Chinese and Indian, in different ways. The various methods of preparing the snails for consumption are described. P. scutata is an intermediate host of the rat-lung worm, Angiostrongylus malaysiensis. As this worm presumably is the causative agent of human eosinophilic meningoencephalitis, the eating habits of the three races in consuming the snail in relation to the epidemiology of the disease was also discussed. PMID:726037

  18. Primeira ocorrência de Biomphalaria straminea no Sul Goiano, Brasil First occurrence of Biomphalaria straminea in the South Goiano, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Marchiori

    1999-12-01

    Full Text Available Relata-se a primeira ocorrência do Biomphalaria straminea no Sul do Estado de Goiás, em ambiente natural. Trinta exemplares de Biomphalaria straminea foram coletados em janeiro de 1998, em Cachoeira Dourada de Goiás. Verificou-se que a falta de saneamento e de educação sanitária da população e a presença do caramujo são condições fundamentais para o estabelecimento de um foco de transmissão.The objective of this note is to report the occurrence of the Biomphalaria straminea in the county of Cachoeira Dourada in the south of Goiás, and with that enhance the knowledge about its geographical distribution in the state. More than identify the species, the collection of thirty samples helped study and verify the presence of cercariae, especially because they were found in a setting which offers proper conditions to the development of a focal transmission site of schistosomiasis.

  19. Haemolymph Components of Infected & None Infected Lymnaea Snails with Xiphidiocercariae

    Directory of Open Access Journals (Sweden)

    AA Saboor Yaraghi

    2011-03-01

    Full Text Available Background: In this study the haemolymph components of infected and none infected Lymnaea gedrosiana with xiphidiocercaria larvae was compared.Methods: Five hundred Fifty Lymnaea snails were collected from Ilam and Mazandaran prov­inces, Iran, during 2008-2009. The snails were transported to the lab at Tehran University of Medi­cal Sciences and their cercarial sheddings were studied. Haemolmyphs of snails were ex­tracted and cells were counted using haemocytometer and cell-surface carbohydrate were recog­nized by conjugated lectin (Lentil. Haemolymph protein concentrations were measured by Brad­ford protein assay method and soluble protein compositions were determined on sodium dodecyl sulphate polyacrilamide gel electrophoresis (SDS-PAGE.Result: From the 550 examined Lymnaea snails for cercariae, 27 snails were infected with xiphidiocer­cariae. Mean of haemolymph cells (haemocyte number were obtained 93480±2.43 (cells/ml for none infected snails (25 snail and 124560±2800 (cells/ml for infected snails (25 snail. Mannose carbohydrate was recognized on haemocyte of none infected and infected snails. Mean of protein concentration of haemolymph plasma was obtained as 1354 ± 160 μg/ml (1.4 mg/ml for none infected snails (25 snails and 1802±138 μg/ml (1.8 mg/ml for infected snail (25 snails. Comparing to none infected snails, the SDS-PAGE results of haemolymph plasma of infected snails, showed an extra protein band (70 kDa. The results showed a significant differ­ence between the amounts and the kinds of proteins in haemolymph of infected and none infected snails.Conclusion: This information might be useful to understand of parasite detection, adhesion, engulf­ment and antigen agglutination by snail.

  20. Dissection of Ire1 functions reveals stress response mechanisms uniquely evolved in Candida glabrata.

    Directory of Open Access Journals (Sweden)

    Taiga Miyazaki

    2013-01-01

    Full Text Available Proper protein folding in the endoplasmic reticulum (ER is vital in all eukaryotes. When misfolded proteins accumulate in the ER lumen, the transmembrane kinase/endoribonuclease Ire1 initiates splicing of HAC1 mRNA to generate the bZIP transcription factor Hac1, which subsequently activates its target genes to increase the protein-folding capacity of the ER. This cellular machinery, called the unfolded protein response (UPR, is believed to be an evolutionarily conserved mechanism in eukaryotes. In this study, we comprehensively characterized mutant phenotypes of IRE1 and other related genes in the human fungal pathogen Candida glabrata. Unexpectedly, Ire1 was required for the ER stress response independently of Hac1 in this fungus. C. glabrata Ire1 did not cleave mRNAs encoding Hac1 and other bZIP transcription factors identified in the C. glabrata genome. Microarray analysis revealed that the transcriptional response to ER stress is not mediated by Ire1, but instead is dependent largely on calcineurin signaling and partially on the Slt2 MAPK pathway. The loss of Ire1 alone did not confer increased antifungal susceptibility in C. glabrata contrary to UPR-defective mutants in other fungi. Taken together, our results suggest that the canonical Ire1-Hac1 UPR is not conserved in C. glabrata. It is known in metazoans that active Ire1 nonspecifically cleaves and degrades a subset of ER-localized mRNAs to reduce the ER load. Intriguingly, this cellular response could occur in an Ire1 nuclease-dependent fashion in C. glabrata. We also uncovered the attenuated virulence of the C. glabrata Δire1 mutant in a mouse model of disseminated candidiasis. This study has unveiled the unique evolution of ER stress response mechanisms in C. glabrata.

  1. Partial Decay of Thiamine Signal Transduction Pathway Alters Growth Properties of Candida glabrata.

    Science.gov (United States)

    Iosue, Christine L; Attanasio, Nicholas; Shaik, Noor F; Neal, Erin M; Leone, Sarah G; Cali, Brian J; Peel, Michael T; Grannas, Amanda M; Wykoff, Dennis D

    2016-01-01

    The phosphorylated form of thiamine (Vitamin B1), thiamine pyrophosphate (TPP) is essential for the metabolism of amino acids and carbohydrates in all organisms. Plants and microorganisms, such as yeast, synthesize thiamine de novo whereas animals do not. The thiamine signal transduction (THI) pathway in Saccharomyces cerevisiae is well characterized. The ~10 genes required for thiamine biosynthesis and uptake are transcriptionally upregulated during thiamine starvation by THI2, THI3, and PDC2. Candida glabrata, a human commensal and opportunistic pathogen, is closely related to S. cerevisiae but is missing half of the biosynthetic pathway, which limits its ability to make thiamine. We investigated the changes to the THI pathway in C. glabrata, confirming orthologous functions. We found that C. glabrata is unable to synthesize the pyrimidine subunit of thiamine as well as the thiamine precursor vitamin B6. In addition, THI2 (the gene encoding a transcription factor) is not present in C. glabrata, indicating a difference in the transcriptional regulation of the pathway. Although the pathway is upregulated by thiamine starvation in both species, C. glabrata appears to upregulate genes involved in thiamine uptake to a greater extent than S. cerevisiae. However, the altered regulation of the THI pathway does not alter the concentration of thiamine and its vitamers in the two species as measured by HPLC. Finally, we demonstrate potential consequences to having a partial decay of the THI biosynthetic and regulatory pathway. When the two species are co-cultured, the presence of thiamine allows C. glabrata to rapidly outcompete S. cerevisiae, while absence of thiamine allows S. cerevisiae to outcompete C. glabrata. This simplification of the THI pathway in C. glabrata suggests its environment provides thiamine and/or its precursors to cells, whereas S. cerevisiae is not as reliant on environmental sources of thiamine. PMID:27015653

  2. Partial Decay of Thiamine Signal Transduction Pathway Alters Growth Properties of Candida glabrata

    Science.gov (United States)

    Shaik, Noor F.; Neal, Erin M.; Leone, Sarah G.; Cali, Brian J.; Peel, Michael T.; Grannas, Amanda M.; Wykoff, Dennis D.

    2016-01-01

    The phosphorylated form of thiamine (Vitamin B1), thiamine pyrophosphate (TPP) is essential for the metabolism of amino acids and carbohydrates in all organisms. Plants and microorganisms, such as yeast, synthesize thiamine de novo whereas animals do not. The thiamine signal transduction (THI) pathway in Saccharomyces cerevisiae is well characterized. The ~10 genes required for thiamine biosynthesis and uptake are transcriptionally upregulated during thiamine starvation by THI2, THI3, and PDC2. Candida glabrata, a human commensal and opportunistic pathogen, is closely related to S. cerevisiae but is missing half of the biosynthetic pathway, which limits its ability to make thiamine. We investigated the changes to the THI pathway in C. glabrata, confirming orthologous functions. We found that C. glabrata is unable to synthesize the pyrimidine subunit of thiamine as well as the thiamine precursor vitamin B6. In addition, THI2 (the gene encoding a transcription factor) is not present in C. glabrata, indicating a difference in the transcriptional regulation of the pathway. Although the pathway is upregulated by thiamine starvation in both species, C. glabrata appears to upregulate genes involved in thiamine uptake to a greater extent than S. cerevisiae. However, the altered regulation of the THI pathway does not alter the concentration of thiamine and its vitamers in the two species as measured by HPLC. Finally, we demonstrate potential consequences to having a partial decay of the THI biosynthetic and regulatory pathway. When the two species are co-cultured, the presence of thiamine allows C. glabrata to rapidly outcompete S. cerevisiae, while absence of thiamine allows S. cerevisiae to outcompete C. glabrata. This simplification of the THI pathway in C. glabrata suggests its environment provides thiamine and/or its precursors to cells, whereas S. cerevisiae is not as reliant on environmental sources of thiamine. PMID:27015653

  3. Silver colloidal nanoparticles : antifungal effect against Candida albicans and Candida glabrata adhered cells and biofilms

    OpenAIRE

    Monteiro, D. R.; Gorup, L. F.; Silva, Sónia Carina; Negri, M.; E. R. Camargo; Oliveira, Rosário; Barbosa, D. B.; Henriques, Mariana

    2011-01-01

    The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applie...

  4. Partial Decay of Thiamine Signal Transduction Pathway Alters Growth Properties of Candida glabrata.

    Directory of Open Access Journals (Sweden)

    Christine L Iosue

    Full Text Available The phosphorylated form of thiamine (Vitamin B1, thiamine pyrophosphate (TPP is essential for the metabolism of amino acids and carbohydrates in all organisms. Plants and microorganisms, such as yeast, synthesize thiamine de novo whereas animals do not. The thiamine signal transduction (THI pathway in Saccharomyces cerevisiae is well characterized. The ~10 genes required for thiamine biosynthesis and uptake are transcriptionally upregulated during thiamine starvation by THI2, THI3, and PDC2. Candida glabrata, a human commensal and opportunistic pathogen, is closely related to S. cerevisiae but is missing half of the biosynthetic pathway, which limits its ability to make thiamine. We investigated the changes to the THI pathway in C. glabrata, confirming orthologous functions. We found that C. glabrata is unable to synthesize the pyrimidine subunit of thiamine as well as the thiamine precursor vitamin B6. In addition, THI2 (the gene encoding a transcription factor is not present in C. glabrata, indicating a difference in the transcriptional regulation of the pathway. Although the pathway is upregulated by thiamine starvation in both species, C. glabrata appears to upregulate genes involved in thiamine uptake to a greater extent than S. cerevisiae. However, the altered regulation of the THI pathway does not alter the concentration of thiamine and its vitamers in the two species as measured by HPLC. Finally, we demonstrate potential consequences to having a partial decay of the THI biosynthetic and regulatory pathway. When the two species are co-cultured, the presence of thiamine allows C. glabrata to rapidly outcompete S. cerevisiae, while absence of thiamine allows S. cerevisiae to outcompete C. glabrata. This simplification of the THI pathway in C. glabrata suggests its environment provides thiamine and/or its precursors to cells, whereas S. cerevisiae is not as reliant on environmental sources of thiamine.

  5. Influence of growth conditions on cell surface hydrophobicity of Candida albicans and Candida glabrata.

    OpenAIRE

    Hazen, K C; Plotkin, B. J.; Klimas, D M

    1986-01-01

    The effect of cultural conditions on cell surface hydrophobicity of Candida albicans and Candida glabrata was tested. C. albicans cells grown at room temperature were more hydrophobic than cells grown at 37 degrees C. No consistent pattern was observed with C. glabrata. Relative hydrophobicity was found to vary with the growth phase and growth medium for both species. The implications for pathogenesis studies are discussed.

  6. Modeling freshwater snail habitat suitability and areas of potential snail-borne disease transmission in Uganda

    DEFF Research Database (Denmark)

    Stensgaard, Anna-Sofie; Jørgensen, Aslak; Kabatereine, N B;

    2006-01-01

    Geographic information system (GIS-based modeling of an intermediate host snail species environmental requirements using known occurrence records can provide estimates of its spatial distribution. When other data are lacking, this can be used as a rough spatial prediction of potential snail...

  7. Oxidative stress response to menadione and cumene hydroperoxide in the opportunistic fungal pathogen Candida glabrata

    Directory of Open Access Journals (Sweden)

    Mayra Cuéllar-Cruz

    2009-07-01

    Full Text Available Candida glabrata is an opportunistic fungal pathogen that can cause severe invasive infections and can evade phagocytic cell clearance. We are interested in understanding the virulence of this fungal pathogen, in particular its oxidative stress response. Here we investigated C. glabrata, Saccharomyces cerevisiae and Candida albicans responses to two different oxidants: menadione and cumene hydroperoxide (CHP. In log-phase, in the presence of menadione, C. glabrata requires Cta1p (catalase, while in a stationary phase (SP, Cta1p is dispensable. In addition, C. glabrata is less resistant to menadione than C. albicans in SP. The S. cerevisiae laboratory reference strain is less resistant to menadione than C. glabrata and C. albicans; however S. cerevisiaeclinical isolates (CIs are more resistant than the lab reference strain. Furthermore, S. cerevisiae CIs showed an increased catalase activity. Interestingly, in SP C. glabrata and S. cerevisiae are more resistant to CHP than C. albicans and Cta1p plays no apparent role in detoxifying this oxidant.

  8. MALDI-TOF typing highlights geographical and fluconazole resistance clusters in Candida glabrata.

    Science.gov (United States)

    Dhieb, C; Normand, A C; Al-Yasiri, M; Chaker, E; El Euch, D; Vranckx, K; Hendrickx, M; Sadfi, N; Piarroux, R; Ranque, S

    2015-06-01

    Utilizing matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra for Candida glabrata typing would be a cost-effective and easy-to-use alternative to classical DNA-based typing methods. This study aimed to use MALDI-TOF for the typing of C. glabrata clinical isolates from various geographical origins and test its capacity to differentiate between fluconazole-sensitive and -resistant strains.Both microsatellite length polymorphism (MLP) and MALDI-TOF mass spectra of 58 C. glabrata isolates originating from Marseilles (France) and Tunis (Tunisia) as well as collection strains from diverse geographic origins were analyzed. The same analysis was conducted on a subset of C. glabrata isolates that were either susceptible (MIC ≤ 8 mg/l) or resistant (MIC ≥ 64 mg/l) to fluconazole.According to the seminal results, both MALDI-TOF and MLP classifications could highlight C. glabrata population structures associated with either geographical dispersal barriers (p MLP resulted in distinct classifications, MALDI-TOF also classified the isolates with respect to their fluconazole susceptibility profile. Further prospective studies are required to evaluate the capacity of MALDI-TOF typing to investigate C. glabrata infection outbreaks and predict the antifungal susceptibility profile of clinical laboratory isolates. PMID:25841053

  9. Behavioural responses of the snail Lymnaea acuminata to carbohydrates in snail-attractant pellets

    Science.gov (United States)

    Tiwari, Farindra; Singh, D. K.

    Snail control is one of the most important tools in the campaign to reduce the incidence of fascioliasis. In order to attain this objective, the method of bait formulation in order to contain an attractant and a molluscicide is an expedient approach to lure the target snail population to the molluscicide. This study identifies certain carbohydrates, namely sucrose, maltose, glucose, fructose and starch, for preparing such baits. These were tested on Lymnaea acuminata, an intermediate host of the digenean trematodes Fasciola hepatica and Fasciola gigantica. The behavioural responses of snails to these carbohydrates were examined. Significant variations in behavioural responses were observed in the snail even when the five carbohydrates were used in low concentrations in snail-attractant pellets. Starch emerged as the strongest attractant for Lymnaea acuminata, followed by maltose.

  10. NCBI nr-aa BLAST: CBRC-TTRU-01-0244 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0244 ref|NP_976171.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata...] gb|AAQ74249.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] gb|AAQ75768.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] NP_976171.1 0.001 26% ...

  11. NCBI nr-aa BLAST: CBRC-TTRU-01-0990 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0990 ref|NP_976171.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata...] gb|AAQ74249.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] gb|AAQ75768.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] NP_976171.1 0.049 25% ...

  12. NCBI nr-aa BLAST: CBRC-TTRU-01-1229 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-1229 ref|NP_976171.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata...] gb|AAQ74249.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] gb|AAQ75768.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] NP_976171.1 0.004 26% ...

  13. NCBI nr-aa BLAST: CBRC-TTRU-01-0907 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-0907 ref|NP_976171.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata...] gb|AAQ74249.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] gb|AAQ75768.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] NP_976171.1 0.038 23% ...

  14. NCBI nr-aa BLAST: CBRC-TTRU-01-1060 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TTRU-01-1060 ref|NP_976171.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata...] gb|AAQ74249.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] gb|AAQ75768.1| ATP synthase F0 subunit 6 [Biomphalaria glabrata] NP_976171.1 0.007 26% ...

  15. Snail-Killing Effects of Streptomyces 218 Powder

    OpenAIRE

    V.O. Aina; A.A.J. Adewumi; C.O. Yao; M.Z. Shi; Hu, D. Y.; W.H. Chai

    2012-01-01

    This study is aimed at finding out the snail-killing effects of Streptomyces 218 powder on Oncomelania hupensis snails which are the vectors or intermediate host of Schiltosoma Japonicum (intestinal schistosomiasis) in china the tests were carried out in the laboratory and on the field. The snail-killing effects of Streptomyces218 powder, isolated from snail habitat at Anchang Village of Anxiang country in China was tested using the immersion and spraying methods. The tests on the Oncomelania...

  16. Energy saving through trail following in a marine snail

    OpenAIRE

    Davies, Mark S; Blackwell, Janine

    2007-01-01

    Most snails and slugs locomote over a layer of mucus and although the resultant mucus trail is expensive to produce, we show that this expense can be reduced by trail following. When tracking over fresh conspecific trails, the marine intertidal snail Littorina littorea (L.) produced only approximately 27% of the mucus laid by marker snails. When tracking over weathered trails, snails adjusted their mucus production to recreate a convex trail profile of similar shape and thickness to the trail...

  17. A Murine Model of Candida glabrata Vaginitis Shows No Evidence of an Inflammatory Immunopathogenic Response.

    Science.gov (United States)

    Nash, Evelyn E; Peters, Brian M; Lilly, Elizabeth A; Noverr, Mairi C; Fidel, Paul L

    2016-01-01

    Candida glabrata is the second most common organism isolated from women with vulvovaginal candidiasis (VVC), particularly in women with uncontrolled diabetes mellitus. However, mechanisms involved in the pathogenesis of C. glabrata-associated VVC are unknown and have not been studied at any depth in animal models. The objective of this study was to evaluate host responses to infection following efforts to optimize a murine model of C. glabrata VVC. For this, various designs were evaluated for consistent experimental vaginal colonization (i.e., type 1 and type 2 diabetic mice, exogenous estrogen, varying inocula, and co-infection with C. albicans). Upon model optimization, vaginal fungal burden and polymorphonuclear neutrophil (PMN) recruitment were assessed longitudinally over 21 days post-inoculation, together with vaginal concentrations of IL-1β, S100A8 alarmin, lactate dehydrogenase (LDH), and in vivo biofilm formation. Consistent and sustained vaginal colonization with C. glabrata was achieved in estrogenized streptozotocin-induced type 1 diabetic mice. Vaginal PMN infiltration was consistently low, with IL-1β, S100A8, and LDH concentrations similar to uninoculated mice. Biofilm formation was not detected in vivo, and co-infection with C. albicans did not induce synergistic immunopathogenic effects. This data suggests that experimental vaginal colonization of C. glabrata is not associated with an inflammatory immunopathogenic response or biofilm formation. PMID:26807975

  18. A Murine Model of Candida glabrata Vaginitis Shows No Evidence of an Inflammatory Immunopathogenic Response.

    Directory of Open Access Journals (Sweden)

    Evelyn E Nash

    Full Text Available Candida glabrata is the second most common organism isolated from women with vulvovaginal candidiasis (VVC, particularly in women with uncontrolled diabetes mellitus. However, mechanisms involved in the pathogenesis of C. glabrata-associated VVC are unknown and have not been studied at any depth in animal models. The objective of this study was to evaluate host responses to infection following efforts to optimize a murine model of C. glabrata VVC. For this, various designs were evaluated for consistent experimental vaginal colonization (i.e., type 1 and type 2 diabetic mice, exogenous estrogen, varying inocula, and co-infection with C. albicans. Upon model optimization, vaginal fungal burden and polymorphonuclear neutrophil (PMN recruitment were assessed longitudinally over 21 days post-inoculation, together with vaginal concentrations of IL-1β, S100A8 alarmin, lactate dehydrogenase (LDH, and in vivo biofilm formation. Consistent and sustained vaginal colonization with C. glabrata was achieved in estrogenized streptozotocin-induced type 1 diabetic mice. Vaginal PMN infiltration was consistently low, with IL-1β, S100A8, and LDH concentrations similar to uninoculated mice. Biofilm formation was not detected in vivo, and co-infection with C. albicans did not induce synergistic immunopathogenic effects. This data suggests that experimental vaginal colonization of C. glabrata is not associated with an inflammatory immunopathogenic response or biofilm formation.

  19. Efficient Mating-Type Switching in Candida glabrata Induces Cell Death

    Science.gov (United States)

    Boisnard, Stéphanie; Zhou Li, Youfang; Arnaise, Sylvie; Sequeira, Gregory; Raffoux, Xavier; Enache-Angoulvant, Adela; Bolotin-Fukuhara, Monique; Fairhead, Cécile

    2015-01-01

    Candida glabrata is an apparently asexual haploid yeast that is phylogenetically closer to Saccharomyces cerevisiae than to Candida albicans. Its genome contains three MAT-like cassettes, MAT, which encodes either MATa or MATalpha information in different strains, and the additional loci, HML and HMR. The genome also contains an HO gene homolog, but this yeast has never been shown to switch mating-types spontaneously, as S. cerevisiae does. We have recently sequenced the genomes of the five species that, together with C. glabrata, make up the Nakaseomyces clade. All contain MAT-like cassettes and an HO gene homolog. In this work, we express the HO gene of all Nakaseomyces and of S. cerevisiae in C. glabrata. All can induce mating-type switching, but, despite the larger phylogenetic distance, the most efficient endonuclease is the one from S. cerevisiae. Efficient mating-type switching in C. glabrata is accompanied by a high cell mortality, and sometimes results in conversion of the additional cassette HML. Mortality probably results from the cutting of the HO recognition sites that are present, in HML and possibly HMR, contrary to what happens naturally in S. cerevisiae. This has implications in the life-cycle of C. glabrata, as we show that efficient MAT switching is lethal for most cells, induces chromosomal rearrangements in survivors, and that the endogenous HO is probably rarely active indeed. PMID:26491872

  20. Planorbis meridaensis Preston, 1907 (Gastropoda: Planorbidae), a synonym of Biomphalaria prona (Martens, 1873)

    OpenAIRE

    W. Lobato Paraense

    1992-01-01

    Biomphalaria prona from Lake Valencia, Venezuela (type locality) has a polymorphic shell wich in the great majority of specimens is wider, with fewer rapidly expanding whorls, the outer one subcarinate on the left side and more or less strongly deflected leftward. Besides those modal forms there are little frequent variants characterized by narrower shell with less rapidly expanding, regularly curved whorls directed forward. Recent studies have shown that such variants constitute the predomin...

  1. Calcium, snails, and birds: a case study

    Directory of Open Access Journals (Sweden)

    R. Mänd

    2000-10-01

    Full Text Available Recent studies have shown that wild birds breeding in acidified areas have difficulties with obtaining sufficient calcium for their eggshells, and that the cause of it is the shortage of land snails. Many birds have to search for Ca-rich snail shells on a daily basis during egg production. Molluscs depend on litter calcium, which has decreased due to acidification of the environment. Calcium limitation may be a widespread phenomenon also in non-acidified, naturally Ca-poor areas. The problem is that while in the latter areas the time for development of specific adaptations may have been sufficient, then in acidified areas, on the contrary, calcium shortage is a recent phenomenon. Therefore, since the extent of calcium limitation in non-acidified areas is hard to derive from observational data, experimental approach is needed. We provide experimental evidence that specific calcium deficit does affect reproductive traits also in the birds breeding in naturally base-poor habitats. Our study was conducted in a heterogeneous woodland area in Estonia containing deciduous forest patches as well as base-poor pine forest with low snail abundance. Ca supplementation, using snail shell and chicken eggshell fragments, was carried out for pied flycatchers and great tits. Extra calcium affected positively several reproductive traits like egg volume and eggshell thickness, start of breeding, and fledglings’ parameters. The negative relationship between calcium availability and lay-date suggests that birds adjust their breeding tactics to conditions of Ca deficiency, for example, by postponing laying.

  2. Statement on the identity of apple snails

    DEFF Research Database (Denmark)

    Baker, R.; Candresse, T.; Dormannsné Simon, E.; Gilioli, G.; Grégoire, J.-C.; Jeger, M. J.; Karadjova, O. E.; Lövei, G.; Makowski, D.; Manceau, C.; Navajas, M.; Porta Puglia, A.; Rafoss, T.; Rossi, V.; Schans, J.; Schrader, G.; Urek, G.; van Lenteren, J. C.; Vloutoglou, I; Winter, S.; Zlotina, M.

    2012-01-01

    Following a request by the European Commission, EFSA’s Panel on Plant Health was asked to deliver a statement to clarify the current scientific knowledge regarding the identity of the apple snails in the context of the evaluation of the pest risk analysis prepared by the Spanish Ministry of Envir...

  3. Mate desertion in the snail kite

    Science.gov (United States)

    Beissinger, S.R.; Snyder, N.F.R.

    1988-01-01

    Mate desertion during the breeding cycle was documented at 28 of 36 (78%) snail kite, Rostrhamus sociabilis nests in Florida between 1979 and 1983. Offspring mortality occurred at only one deserted nest, however. Parents that were deserted by their mates continued to care for their young until independence (3?5 additional weeks) and provided snails at a rate similar to that of both parents combined before desertion. Males and females deserted with nearly equal frequency, except in 1982 when more females deserted. No desertion occurred during drought years, whereas desertion occurred at nearly every nest during favourable conditions. The occurrence of mate desertion was generally related to indirect measures of snail abundance: foraging range, snail delivery rates to the young and growth rates. Small broods were deserted more frequently by females than by males and tended to be deserted earlier than large ones. After desertion, deserters had the opportunity to re-mate and nest again since breeding seasons were commonly lengthy, but whether they did so was impossible to determine conclusively in most cases. The deserted bird sometimes incurred increased energetic costs and lost breeding opportunities during periods of monoparental care.

  4. Ensaios preliminares do Guaiacum officinale L. como moluscicida Preliminary tests of Guaiacum officinale L. as molluscicide

    Directory of Open Access Journals (Sweden)

    Nelymar Martineli Mendes

    1993-12-01

    Full Text Available Suspensões aquosas do pericarpo do fruto, da casca da raiz, das folhas e das sementes de Guaiacum officinale foram testadas como moluscicida, cercaricida e piscicida em diferentes concentrações. Em laboratório, a suspensão do pericarpo do fruto apresentou 100% de mortalidade a 100 ppm para desovas de B. glabrata, a 20 ppm para caramujos adultos de Biomphalaria glabrata, B. straminea e B. tenagophila, a 5 ppm para Lebistes reticulatus (peixes e a 1 ppm para cercárias de Schistosoma mansoni. O extrato etanólico do pericarpo do fruto não foi ativo para caramujo adulto de B. glabrata. As doses letais para 90% dos caramujos adultos (DL90, após 24 horas de exposição, usando a suspensão do pericarpo do fruto foram de: 15 ppm para B. glabrata; 14 ppm para B. straminea e 18 ppm para B. tenagophila. As DL90 das suspensões das casca da raiz, sementes e folhas contra B. glabrata foram de 57, 33 e 15 ppm, respectivamente. No campo, coma suspensão do pericarpo do fruto a mortalidade de caramujos adultos de B. glabrata foi de 68% a 20 ppm e 100% a 40 ppmAqueous suspensions of fruit's pericarp, leaves, root's bark and seeds of Guaiacum officinale were tested at different concentrations as molluscicide, cercaricide and piscicide. In the laboratory the suspension of fruit's pericarp produced 100% mortality for egg masses of B. glabrata at 100 ppm, for adult snails of Biomphalaria glabrata, B. straminea and B. tenagophila at 20 ppm, for Lebistes reticulatus (fishes at 5 ppm and Schistosoma mansoni's cercariae at 1 ppm. The ethanolic extract of fruit's pericarp was not active against adult snails of B. glabrata. The letal dose for adult snails(DL90 of the aqueous suspension of fruit's pericarp after 24 hours exposure, were: 15 ppm for B. glabrata; 14 ppm for B. straminea and 18 ppm for B. tenagophila. The DL90 of aqueous suspensions of root's bark, seeds and leaves were 57 ppm, 33 ppm and 15 ppm, respectively. In the field, B. glabrata adult snail

  5. Medical treatment of a pacemaker endocarditis due to Candida albicans and to Candida glabrata.

    Science.gov (United States)

    Roger, P M; Boissy, C; Gari-Toussaint, M; Foucher, R; Mondain, V; Vandenbos, F; le Fichoux, Y; Michiels, J F; Dellamonica, P

    2000-09-01

    We describe a case of pacemaker infection due to two fungal species: Candida albicans and C. glabrata. Transthoracic echocardiography showed a large vegetation on the intraventricular wires. Because of severe underlying diseases, surgery was believed to be contraindicated. The patient was treated using high dose of fluconazole, resulting in clinical improvement and negative blood cultures. However, 2 months later, the patient underwent a fatal stroke. At autopsy, a large vegetation was found only all along the wires. Postmortem culture of the infected material was positive for both C. albicans and C. glabrata. PMID:11023765

  6. Spatial analysis of snail distribution in Jiangning county

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-ying; ZHOU Yun; XU De-zhong; SUN Zhi-dong; ZHOU Xiao-nong; GONG Zi-li

    2002-01-01

    Objective: To explore the spatial distribution of oncomelenia snails in Jiangning County. Methods:Cluster analysis and the Spatial Scan Statistics were performed based on the density of alive-snails in habitats and its rate infected by the S. Japonicum. Results: Although areas of snail habitats and density of the alivesnails in marshland in 2000 are higher significantly than that in mountain areas in Jiangning County, the numbers of habitats in mountain are more than that in marshland and they distributed sporadically. The snail habitats were classified into 4 in marshlands and 3 classes in mountain areas respectively in cluster analysis.Although they are mainly the one with low density of alive and infected snails, we should alert that there are also some habitats with high snail density and infection rate, which is important for the transmission of schistosomia. The analysis of Spatial Scan Statistics detected 2 significant spatial aggregations for alive-snail in marshland and 4 in mountain areas respectively with p-values less than 0. 01. There are also 2 significant spatial aggregations for infected snails in marshland. Conclusion.. The significant spatial aggregations for alivesnails and infected snails indicated that there are some factors in the habitats suitable for the survival of snails and the transmission of schistosomia.

  7. Genome-wide survey of transcriptional initiation in the pathogenic fungus, Candida glabrata.

    Science.gov (United States)

    Aoyama, Toshihiro; Nakayama, Hironobu; Ueno, Keigo; Inukai, Tatsuya; Tanabe, Koichi; Nagi, Minoru; Bard, Martin; Chibana, Hiroji

    2014-06-01

    DNA sequencing of the 5'-flanking region of the transcriptome effectively identifies transcription initiation sites and also aids in identifying unknown genes. This study describes a comprehensive polling of transcription start sites and an analysis of full-length complementary DNAs derived from the genome of the pathogenic fungus Candida glabrata. A comparison of the sequence reads derived from a cDNA library prepared from cells grown under different culture conditions against the reference genomic sequence of the Candida Genome Database (CGD: http://www.candidagenome.org/) revealed the expression of 4316 genes and their acknowledged transcription start sites (TSSs). In addition this analysis also predicted 59 new genes including 22 that showed no homology to the genome of Saccharomyces cerevisiae, a genetically close relative of C. glabrata. Furthermore, comparison of the 5'-untranslated regions (5'-UTRs) and core promoters of C. glabrata to those of S. cerevisiae showed various global similarities and differences among orthologous genes. Thus, the C. glabrata transcriptome can complement the annotation of the genome database and should provide new insights into the organization, regulation, and function of genes of this important human pathogen. PMID:24725256

  8. Arteriovenous graft infection caused by Candida glabrata: A case report and literature review.

    Science.gov (United States)

    Huang, Hung-Ling; Lin, Chun-Yu; Chang, Ya-Ting; Chen, Yen-Hsu; Wu, Wei-Tsung; Lu, Po-Liang

    2016-04-01

    The infection rate of arteriovenous (AV) grafts is high, but fungal etiology is rare. Only five cases of graft infection due to Candida albicans (C. albicans) or C. tropicalis have been described in the literature. Herein, we report the first case of AV graft infection caused by C. glabrata. A 60-year-old woman on maintenance hemodialysis for end-stage renal disease was admitted because of intermittent fever, for 10 days. Upon physical examination, tenderness over the AV graft site was noticed. Blood culture yielded C. glabrata and her clinical symptoms improved after she was treated with micafungin for 1 month. However, C. glabrata candidemia reoccurred 5 weeks later. Cure was achieved after removal of the AV graft and anidulafungin treatment. Pus was observed in the removed graft, from which C. glabrata was isolated. The outcome of our case and patients from the literature review suggest that removal of the infected graft is important for treatment success of AV graft Candida infection. PMID:23838263

  9. Potassium Uptake Mediated by Trk1 Is Crucial for Candida glabrata Growth and Fitness

    Czech Academy of Sciences Publication Activity Database

    Llopis-Torregrosa, Vincent; Hušeková, Barbora; Sychrová, Hana

    2016-01-01

    Roč. 11, č. 4 (2016), e0153374. E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GAP302/12/1151; GA ČR(CZ) GA16-03398S Institutional support: RVO:67985823 Keywords : Candida glabrata * potassium uptake * Trk1 protein Subject RIV: EE - Microbiology, Virology Impact factor: 3.234, year: 2014

  10. Mechanisms of azole resistance among clinical isolates of Candida glabrata in Poland.

    Science.gov (United States)

    Szweda, Piotr; Gucwa, Katarzyna; Romanowska, Ewa; Dzierzanowska-Fangrat, Katarzyna; Naumiuk, Łukasz; Brillowska-Dabrowska, Anna; Wojciechowska-Koszko, Iwona; Milewski, Sławomir

    2015-06-01

    Candida glabrata is currently ranked as the second most frequently isolated aetiological agent of human fungal infections, next only to Candida albicans. In comparison with C. albicans, C. glabrata shows lower susceptibility to azoles, the most common agents used in treatment of fungal infections. Interestingly, the mechanisms of resistance to azole agents in C. albicans have been much better investigated than those in C. glabrata. The aim of the presented study was to determine the mechanisms of resistance to azoles in 81 C. glabrata clinical isolates from three different hospitals in Poland. The investigation was carried out with a Sensititre Yeast One test and revealed that 18 strains were resistant to fluconazole, and 15 were cross-resistant to all other azoles tested (voriconazole, posaconazole and itraconazole). One isolate resistant to fluconazole was cross-resistant to voriconazole, and resistance to voriconazole only was observed in six other isolates. All strains were found to be susceptible to echinocandins and amphotericin B, and five were classified as resistant to 5-fluorocytosine. The sequence of the ERG11 gene encoding lanosterol 14-α demethylase (the molecular target of azoles) of 41 isolates, including all strains resistant to fluconazole and three resistant only to voriconazole, was determined, and no amino acid substitutions were found. Real-time PCR studies revealed that 13 of 15 azole-resistant strains showed upregulation of the CDR1 gene encoding the efflux pump. No upregulation of expression of the CDR2 or ERG11 gene was observed. PMID:25818698

  11. Mini-chromosomes among danish Candida glabrata isolates originated through two different mechanisms

    DEFF Research Database (Denmark)

    Ahmad, K. M.; Ishchuk, O.; Hellborg, L.; Jørgensen, G.; Skvarc, M.; Stenderup, Jesper; Jørck-Ramberg, Dorte; Polakova, S.; Piskur, Jure

    2012-01-01

    We analyzed 201 strains of the pathogenic yeast Candida glabrata from patients, mainly suffering from systemic infection, at Danish hospitals during 1985 – 1999. Our analysis showed that these strains were closely related but exhibited large karyotype polymorphism. Nine strains contained mini...

  12. A network of paralogous stress response transcription factors in the human pathogen Candida glabrata.

    Directory of Open Access Journals (Sweden)

    Jawad eMerhej

    2016-05-01

    Full Text Available The yeast Candida glabrata has become the second cause of systemic candidemia in humans. However, relatively few genome-wide studies have been conducted in this organism and our knowledge of its transcriptional regulatory network is quite limited. In the present work, we combined genome-wide chromatin immunoprecipitation (ChIP-seq, transcriptome analyses and DNA binding motif predictions to describe the regulatory interactions of the seven Yap (Yeast AP1 transcription factors of C. glabrata. We described a transcriptional network containing 255 regulatory interactions and 309 potential target genes. We predicted with high confidence the preferred DNA binding sites for 5 of the 7 CgYaps and showed a strong conservation of the Yap DNA binding properties between S. cerevisiae and C. glabrata. We provided reliable functional annotation for 3 of the 7 Yaps and identified for Yap1 and Yap5 a core regulon which is conserved in S. cerevisiae, C. glabrata and C. albicans. We uncovered new roles for CgYap7 in the regulation of iron-sulfur cluster biogenesis, for CgYap1 in the regulation of heme biosynthesis and for CgYap5 in the repression of GRX4 in response to iron starvation. These transcription factors define an interconnected transcriptional network at the cross-roads between redox homeostasis, oxygen consumption and iron metabolism.

  13. Snail1 Mediates Hypoxia-Induced Melanoma Progression

    Science.gov (United States)

    Liu, Shujing; Kumar, Suresh M.; Martin, James S.; Yang, Ruifeng; Xu, Xiaowei

    2011-01-01

    Tumor hypoxia is a known adverse prognostic factor, and the hypoxic dermal microenvironment participates in melanomagenesis. High levels of hypoxia inducible factor (HIF) expression in melanoma cells, particularly HIF-2α, is associated with poor prognosis. The mechanism underlying the effect of hypoxia on melanoma progression, however, is not fully understood. We report evidence that the effects of hypoxia on melanoma cells are mediated through activation of Snail1. Hypoxia increased melanoma cell migration and drug resistance, and these changes were accompanied by increased Snail1 and decreased E-cadherin expression. Snail1 expression was regulated by HIF-2α in melanoma. Snail1 overexpression led to more aggressive tumor phenotypes and features associated with stem-like melanoma cells in vitro and increased metastatic capacity in vivo. In addition, we found that knockdown of endogenous Snail1 reduced melanoma proliferation and migratory capacity. Snail1 knockdown also prevented melanoma metastasis in vivo. In summary, hypoxia up-regulates Snail1 expression and leads to increased metastatic capacity and drug resistance in melanoma cells. Our findings support that the effects of hypoxia on melanoma are mediated through Snail1 gene activation and suggest that Snail1 is a potential therapeutic target for the treatment of melanoma. PMID:21996677

  14. Snail-Killing Effects of Streptomyces 218 Powder

    Directory of Open Access Journals (Sweden)

    V.O. Aina

    2012-12-01

    Full Text Available This study is aimed at finding out the snail-killing effects of Streptomyces 218 powder on Oncomelania hupensis snails which are the vectors or intermediate host of Schiltosoma Japonicum (intestinal schistosomiasis in china the tests were carried out in the laboratory and on the field. The snail-killing effects of Streptomyces218 powder, isolated from snail habitat at Anchang Village of Anxiang country in China was tested using the immersion and spraying methods. The tests on the Oncomelania hupensis snails which are intermediate host of Streptomyces japonicum infection were carried out in the laboratory and in the field. The mean corrected snail mortalities of the immersion technique in the laboratory were 81.70 and 98.63% in 10 ppm of 218 solutions after 24 and 48 h, respectively. The mean corrected snail mortalities of the spraying tests in the laboratory were 82.90 and 87.90% at 3 and 5 days, respectively with 10 g/m2 218 powders. The snail-killing ability of 218 powders on the field determines by immersion and spraying methods were comparable to that of the chemical molluscicide-Niclosamide. The corrected snail mortality at 150 ppm of 218 powder (g/m2 and at 2 ppm of Niclosamide by immersion was 100% at the second time test after 24, 48 and 72 h. In the field spraying test, the mean corrected snail mortality at 100 ppm of 218 powders were 61.96 and 70.00% after 3 and 7 days of spraying respectively. At 2 ppm niclosamide, this was found to be 65.58 and 63.81%, respectively. The effective ingredients for the snail-killing are found to be located in the spore chains. Streptomyces 218 powder, although at higher concentrations, seems to be a promising mollusciciding biological agent. If developed further, this could compliment existing mollusciciding agents.

  15. Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs Variação genética entre moluscos susceptíveis e não susceptíveis à infecção pelo Schistosoma através da análise do DNA polimórfico amplificado aleatóriamente (RAPDs

    Directory of Open Access Journals (Sweden)

    Abdel-Hamid Zaki ABDEL-HAMID

    1999-09-01

    Full Text Available Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers were used to amplify the extracted DNA by the polymerase chain reaction (PCR followed by polyacrylamide gel electrophoresis (PAGE and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.A susceptibilidade de moluscos à infecção por certos trematódeos e a sua capacidade como hospedeiro para o contínuo desenvolvimento é o problema mais deslumbrante nas relações parasita hospedeiro. O presente trabalho, focaliza nosso interesse na genética dos moluscos para determinar quais genes ou produtos gênicos são especificamente responsáveis pela susceptibilidade do molusco à infecção. DNA de alto peso molecular, foi extraído de ambos moluscos susceptíveis e não susceptíveis da espécie Biomphalaria tenagophila. Iniciadores aleatórios com 10 pares de bases foram usados na amplificação aleatória (RAPD de ambos os DNAs e análise por eletroforese em gel de poliacrilamida e coloração com prata. Os resultados mostram que a amplificação aleatória do DNA representa um eficiente caminho para a comparação dos genomas desde que marcadores moleculares foram detectados como variantes genéticos entre os moluscos susceptíveis e não susceptíveis.

  16. Upregulation of the Adhesin Gene EPA1 Mediated by PDR1 in Candida glabrata Leads to Enhanced Host Colonization.

    Science.gov (United States)

    Vale-Silva, Luis A; Moeckli, Beat; Torelli, Riccardo; Posteraro, Brunella; Sanguinetti, Maurizio; Sanglard, Dominique

    2016-01-01

    Candida glabrata is the second most common Candida species causing disseminated infection, after C. albicans. C. glabrata is intrinsically less susceptible to the widely used azole antifungal drugs and quickly develops secondary resistance. Resistance typically relies on drug efflux with transporters regulated by the transcription factor Pdr1. Gain-of-function (GOF) mutations in PDR1 lead to a hyperactive state and thus efflux transporter upregulation. Our laboratory has characterized a collection of C. glabrata clinical isolates in which azole resistance was found to correlate with increased virulence in vivo. Contributing phenotypes were the evasion of adhesion and phagocytosis by macrophages and an increased adhesion to epithelial cells. These phenotypes were found to be dependent on PDR1 GOF mutation and/or C. glabrata strain background. In the search for the molecular effectors, we found that PDR1 hyperactivity leads to overexpression of specific cell wall adhesins of C. glabrata. Further study revealed that EPA1 regulation, in particular, explained the increase in adherence to epithelial cells. Deleting EPA1 eliminates the increase in adherence in an in vitro model of interaction with epithelial cells. In a murine model of urinary tract infection, PDR1 hyperactivity conferred increased ability to colonize the bladder and kidneys in an EPA1-dependent way. In conclusion, this study establishes a relationship between PDR1 and the regulation of cell wall adhesins, an important virulence attribute of C. glabrata. Furthermore, our data show that PDR1 hyperactivity mediates increased adherence to host epithelial tissues both in vitro and in vivo through upregulation of the adhesin gene EPA1. IMPORTANCE Candida glabrata is an important fungal pathogen in human diseases and is also rapidly acquiring drug resistance. Drug resistance can be mediated by the transcriptional activator PDR1, and this results in the upregulation of multidrug transporters. Intriguingly

  17. Upregulation of the Adhesin Gene EPA1 Mediated by PDR1 in Candida glabrata Leads to Enhanced Host Colonization

    OpenAIRE

    Vale-Silva, Luis A.; Moeckli, Beat; Torelli, Riccardo; Posteraro, Brunella; Sanguinetti, Maurizio; Sanglard, Dominique

    2016-01-01

    ABSTRACT Candida glabrata is the second most common Candida species causing disseminated infection, after C. albicans. C. glabrata is intrinsically less susceptible to the widely used azole antifungal drugs and quickly develops secondary resistance. Resistance typically relies on drug efflux with transporters regulated by the transcription factor Pdr1. Gain-of-function (GOF) mutations in PDR1 lead to a hyperactive state and thus efflux transporter upregulation. Our laboratory has characterize...

  18. Comparison of Antifungal Susceptibilities to Fluconazole and Voriconazole of Oral Candida glabrata Isolates from Head and Neck Radiation Patients

    OpenAIRE

    Burn, A. K.; Fothergill, A W; Kirkpatrick, W. R.; Coco, B. J.; Patterson, T F; McCarthy, D I; Rinaldi, M.G.; Redding, S W

    2004-01-01

    The antifungal susceptibilities of 79 oral Candida glabrata isolates to fluconazole and voriconazole were compared. The MICs at which 90% of the isolates tested were inhibited were 1 μg of voriconazole/ml and 32 μg of fluconazole/ml. Oral C. glabrata isolates for which the fluconazole MICs are elevated are commonly those for which the voriconazole MICs are elevated, but these increases may be transient for voriconazole, as they are for fluconazole.

  19. Land Snail Extinctions at Kalaeloa, O`ahu

    Directory of Open Access Journals (Sweden)

    T.S. Dye

    2001-06-01

    Full Text Available In this article we show that the interpretation of Polynesian influence drawn from the stratigraphic record of sub-fossil land snails at Kalaeloa (O'ahu, Hawai'i is based on a unique stratigraphic sequence at a single sinkhole. The interpretation was then applied to other land snail sequences, despite their lack of evidence for Polynesian influence. We present a reanalysis of the stratigraphic record to conclude that Polynesians had little, if any, effect on land snail populations in sinkholes. We show that directional change in land snail populations was underway before Polynesians colonised the islands. Decreases in the diversity of snail populations, possibly indicative of environmental stress, do occur near the end of the stratigraphic sequence. Based on available dating evidence, however, these changes probably took place in the post-Contact period when the regional environment was radically altered by sugar cane cultivation.

  20. Echinocandin resistance and population structure of invasive Candida glabrata isolates from two university hospitals in Germany and Austria.

    Science.gov (United States)

    Klotz, Ulrike; Schmidt, Dirk; Willinger, Birgit; Steinmann, Eike; Buer, Jan; Rath, Peter-Michael; Steinmann, Joerg

    2016-05-01

    Echinocandin resistance in Candida glabrata is emerging and is associated with the presence of FKS mutations. In this study, we analysed the antifungal susceptibility, presence of FKS mutations and clonality of C. glabrata blood culture isolates from two hospitals in Germany and Austria. Susceptibility testing of 64 C. glabrata bloodstream isolates from two university hospitals was performed with broth microdilution method according to EUCAST. In addition, all isolates were screened for FKS mutations. Molecular fingerprinting was performed by microsatellite PCR with three separate primer pairs and semiautomated repetitive sequenced-based PCR (rep-PCR). One C. glabrata isolate from Germany (1.5%) was echinocandin resistant, with a corresponding mutation in FKS2 gene hot spot 1. The discriminatory power of microsatellite PCR was higher than that of rep-PCR (Simpson Index of 0.94 vs. 0.88); microsatellite PCR created 31 separate genotypes, whereas rep-PCR created 17. Predominant genotypes or clusters of isolates from Germany and Austria were present, with no epidemiological evidence of nosocomial transmissions. Although we found a low incidence of echinocandin resistance in C. glabrata in our settings, further surveillance projects in central Europe are warranted for monitoring future epidemiological trends. The genetic population structure of C. glabrata demonstrates overrepresented geographical clusters. PMID:26806376

  1. Small chromosomes among Danish Candida glabrata isolates originated through different mechanisms

    DEFF Research Database (Denmark)

    Ahmad, Khadija Mohamed; Ishchuk, Olena P.; Hellborg, Linda;

    2013-01-01

    participate in their origin: (i) through a segmental duplication which covered the centromeric region, or (ii) by a translocation event moving a larger chromosome arm to another chromosome that leaves the centromere part with the shorter arm. The first type of small chromosomes carrying duplicated genes...... chromosomes, which were smaller than 0.5 Mb. Regarding the year, patient and hospital, these C. glabrata strains had independent origin and the analyzed small chromosomes were structurally not related to each other (i.e. they contained different sets of genes). We suggest that at least two mechanisms could...... exhibited mitotic instability, while the second type, which contained the corresponding genes in only one copy in the genome, was mitotically stable. Apparently, in patients C. glabrata chromosomes are frequently reshuffled resulting in new genetic configurations, including appearance of small chromosomes...

  2. Mini-chromosomes among danish Candida glabrata isolates originated through two different mechanisms

    DEFF Research Database (Denmark)

    Ahmad, K. M.; Ishchuk, O.; Hellborg, L.;

    2012-01-01

    ) through a segmental duplication which covered the centromeric region, and (ii) by a translocation event moving a larger chromosome arm to another chromosome that leaves the centromere part with the shorter arm. The first type of mini-chromosomes carrying duplicated genes exhibited mitotic instability......We analyzed 201 strains of the pathogenic yeast Candida glabrata from patients, mainly suffering from systemic infection, at Danish hospitals during 1985 – 1999. Our analysis showed that these strains were closely related but exhibited large karyotype polymorphism. Nine strains contained mini-chromosomes......, which were smaller than 0.5 Mb. Regarding the year, patient and hospital, C. glabrata strains had independent origin and the analyzed mini-chromosomes were struc- turally not related to each other (i.e., they contained different sets o genes). We inferred two mechanisms involved in their origin: (i...

  3. How parasitism, stream substrate, and movement patterns mediate response to disturbance in the snail Elimia flava

    Science.gov (United States)

    Tomba, A. M.; Feminella, J. W.

    2005-05-01

    Snails in the genus Elimia are abundant in southeastern USA streams, and also serve as intermediate hosts to parasitic trematodes. Previous work indicated that high-flows decrease snail abundance and trematode prevalence, and others have shown substrate type and snail size affect likelihood of snail dislodgement. To investigate how parasitism, size, substrate, and snail behavior influenced dislodgement, we placed Elimia flava in artificial streams containing tile or gravel substrates, and then exposed them to progressively increasing flow velocities ( ~10, 40, 90 cm/s) for 5 minutes each. We recorded snail behavior and time to dislodgement, and then preserved snails to quantify their size and parasite load. Snails on tile dislodged significantly faster than snails on gravel, and snails with high parasite loads also dislodged faster than snails without parasites. Parasitism also appeared to affect movement patterns: snails showing predominantly downstream movement had higher parasite loads than those that did not. Behavior also affected dislodgement probability, as snails moving upstream or to the waterline remained on the substrate longer than snails not showing those behaviors. Parasitism, substrate composition, and snail movement are useful predictors of the likelihood of dislodgement, and parasitism and substrate may both increase snail vulnerability to flow disturbance.

  4. Modeling snail breeding in Bioregenerative Life Support System

    Science.gov (United States)

    Kovalev, Vladimir; Tikhomirov, Alexander A.; Nickolay Manukovsky, D..

    It is known that snail meat is a high quality food that is rich in protein. Hence, heliciculture or land snail farming spreads worldwide because it is a profitable business. The possibility to use the snails of Helix pomatia in Biological Life Support System (BLSS) was studied by Japanese Researches. In that study land snails were considered to be producers of animal protein. Also, snail breeding was an important part of waste processing, because snails were capable to eat the inedible plant biomass. As opposed to the agricultural snail farming, heliciculture in BLSS should be more carefully planned. The purpose of our work was to develop a model for snail breeding in BLSS that can predict mass flow rates in and out of snail facility. There are three linked parts in the model called “Stoichiometry”, “Population” and “Mass balance”, which are used in turn. Snail population is divided into 12 age groups from oviposition to one year. In the submodel “Stoichiometry” the individual snail growth and metabolism in each of 12 age groups are described with stoichiometry equations. Reactants are written on the left side of the equations, while products are written on the right side. Stoichiometry formulas of reactants and products consist of four chemical elements: C, H, O, N. The reactants are feed and oxygen, products are carbon dioxide, metabolic water, snail meat, shell, feces, slime and eggs. If formulas of substances in the stoichiometry equations are substituted with their molar masses, then stoichiometry equations are transformed to the equations of molar mass balance. To get the real mass balance of individual snail growth and metabolism one should multiply the value of each molar mass in the equations on the scale parameter, which is the ratio between mass of monthly consumed feed and molar mass of feed. Mass of monthly consumed feed and stoichiometry coefficients of formulas of meat, shell, feces, slime and eggs should be determined experimentally

  5. Role of CgCnh1 antiporter in tolerance of Candida glabrata to alkali metal cations

    Czech Academy of Sciences Publication Activity Database

    Krauke, Yannick; Sychrová, Hana

    New Jersey : American Society of Microbiology, 2008. s. 46-47. [Candida and Candidiasis /9./. 24.03.2008-28.03.2008, Jersey City] R&D Projects: GA MŠk(CZ) LC531 Institutional research plan: CEZ:AV0Z50110509 Source of funding: R - rámcový projekt EK Keywords : spo2 * Candida glabrata * salt tolerance * antiporter Subject RIV: EE - Microbiology, Virology

  6. UPC2A is required for high-level azole antifungal resistance in Candida glabrata.

    Science.gov (United States)

    Whaley, Sarah G; Caudle, Kelly E; Vermitsky, John-Paul; Chadwick, Sean G; Toner, Geoffrey; Barker, Katherine S; Gygax, Scott E; Rogers, P David

    2014-08-01

    Candida glabrata, the second most common cause of Candida infections, is associated with high rates of mortality and often exhibits resistance to the azole class of antifungal agents. Upc2 and Ecm22 in Saccharomyces cerevisiae and Upc2 in Candida albicans are the transcriptional regulators of ERG11, the gene encoding the target of azoles in the ergosterol biosynthesis pathway. Recently two homologs for these transcription factors, UPC2A and UPC2B, were identified in C. glabrata. One of these, UPC2A, was shown to influence azole susceptibility. We hypothesized that due to the global role for Upc2 in sterol biosynthesis in S. cerevisiae and C. albicans, disruption of UPC2A would enhance the activity of fluconazole in both azole-susceptible dose-dependent (SDD) and -resistant C. glabrata clinical isolates. To test this hypothesis, we constructed mutants with disruptions in UPC2A and UPC2B alone and in combination in a matched pair of clinical azole-SDD and -resistant isolates. Disruption of UPC2A in both the SDD and resistant isolates resulted in increased susceptibility to sterol biosynthesis inhibitors, including a reduction in fluconazole MIC and minimum fungicidal concentration, enhanced azole activity by time-kill analysis, a decrease in ergosterol content, and downregulation of baseline and inducible expression of several sterol biosynthesis genes. Our results indicate that Upc2A is a key regulator of ergosterol biosynthesis and is essential for resistance to sterol biosynthesis inhibitors in C. glabrata. Therefore, the UPC2A pathway may represent a potential cotherapeutic target for enhancing azole activity against this organism. PMID:24867980

  7. Dark recovery phenomena in the pathogenic yeast Torulopsis glabrata irradiated by ultraviolet light

    International Nuclear Information System (INIS)

    The capacity of Torulopsis glabrata (T. glabrata) (a mycomycetes) separated from human oral cavity to recover from ultraviolet injuries were investigated. When cells irradiated with ultraviolet rays were kept in purified water at 270C before planting cells on agar culture medium for colony formation, survival rate of cells recovered according to an increase in the period of liquid holding. The recovery of the survival rate of cells at logarithm proliferation stage was higher than that of cells at normal stage. The time necessary for the recovery of the survival rate of cells exposed to ultraviolet ray by liquid holding became longer according to an increase in exposure dose. Caffeine reduced the survival rate of cells exposed to ultraviolet ray specifically when it was added with the concentrations which did not influence the survival rate of non-exposed cells at all. This suggested that caffeine acted on ultraviolet injuries of DNA. The recovery of the survival rate of cells was inhibited when caffeine was added during liquid holding. However, the effect of caffeine to inhibit the recovery of the survival rate was reduced when caffeine was added after liquid holding. Therefore, it was recognized that caffeine acted on as an inhibitor against DNA repair. Abovementioned recovery of the survival rate of cells by liquid holding and the effect of caffeine to inhibit DNA repair resembled the results in other living bodies having dark recovery capacity, which suggested that T. glabrata had the capacity to repair DNA. (Tsunoda, M.)

  8. The emerging role of Snail1 in the tumor stroma.

    Science.gov (United States)

    Herrera, A; Herrera, M; Peña, C

    2016-09-01

    The transcription factor Snail1 leads to the epithelial-mesenchymal transition by repressing the adherent and tight junctions in epithelial cells. This process is related to an increase of cell migratory and mesenchymal properties during both embryonic development and tumor progression. Although Snail1 expression is very limited in adult animals, emerging evidence has placed Snail at the forefront of medical science. As a transcriptional repressor, Snail1 confers cancer stem cell-like traits on tumor cells and promotes drug resistance, tumor recurrence and metastasis. In this review, we summarize recent reports that suggest the pro-tumorigenic roles of Snail1 expression in tumor stroma. The crosstalk between tumor and stromal cells mediated by Snail1 regulates paracrine communication, pro-tumorigenic abilities of cancer cells, extracellular matrix characteristics and mesenchymal differentiation in cancer stem cells and cancer-associated fibroblasts. Therefore, understanding the regulation and functional roles of Snail1 in the tumor microenvironment will provide us with new therapies for treating metastatic disease. PMID:26687368

  9. Anti-ulcer potentials of phylum mollusca (tropical snail) slime

    Institute of Scientific and Technical Information of China (English)

    Nwodo NJ; Okonta J M; Ezugwu CO; Attama AA

    2009-01-01

    Objective:The effectiveness of the slimy substance in snail to regenerate and repair damaged areas on its body/shell lead to this investigation.Methods:The anti-ulcer'property of snail slime extracted from phylum mollusca (tropical snail)from the giant African snail Archachatina marginata (Fam.Arionidae)was investi-gated using histamine,stress and indomethacin-induced ulcers.The solubility profile of extract was investiga-ted in different solvents and at different temperatures.Chemical analysis was carried out to determine the types of constituents present in the slim,while acute toxicity test was carried out to evaluate its profile of toxicity. The effect of the snail slim on gastrointestinal motility was investigated in mice,while the guinea pig ileum was used to study the effect of the extract on contraction produced by acetylcholine and histamine.The snail slime contained copious quantity of protein,with varying amounts of simple sugars,carbohydrates and fats.The slime was not soluble in most common solvents and increases in temperature,did not appear to increase its sol-ubility.Results:The result further indicated that although the snail slime exhibited significant (P <0.05)an-ti-ulcer induced by stress and histamine,it was most potent against ulcer induced by indomethacin.The snail slime potently inhibited gastrointestinal movement in mice in a dose-dependent manner;however,it was not a-ble to inhibit contraction induced by acetylcholine and histamine in guinea pig ileum.Conclusion:The snail mucin possesses potent antiulcer properties without any toxic effect.The mechanism responsible for the anti-ul-cer property may not be postulated with certainty but cytoprotective and anti-spasmodic activities are most likely to be involved.

  10. Molecular diversity of avian schistosomes in Danish freshwater snails

    DEFF Research Database (Denmark)

    Christiansen, Anne Ø.; Olsen, Annette; Buchmann, Kurt; Kania, Per Walter; Nejsum, Peter; Vennervald, Birgitte J

    2015-01-01

    Avian schistosomes are widespread parasites of snails and waterfowl and may cause cercarial dermatitis (swimmer's itch) in humans, a disease that is frequently reported in European countries. These parasites are known to occur in Denmark, but here, we applied a new approach using molecular tools to...... subjected to molecular investigation by sequencing and phylogenetic analysis of the 5.8S and ITS2 ribosomal DNA for species identification. Additionally, snail hosts belonging to the genus Radix were identified by sequencing and phylogenetic analysis of partial ITS2 ribosomal DNA. Three out of 499 snails...

  11. Snails, stable iostopes, and southwestern desert paleoclimates

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, S.E. [Univ. and Community College System of Nevada, Reno, NV (United States); Whelan, J.F.; Forester, R.M.; Burdett, J.

    1995-09-01

    Modern and fossil molluscs (snails) occur in many localities in and semi-arid regions throughout the desert southwest. Live terrestrial snails are found under rocks and in forest litter and aquatic taxa inhabit springs, seeps, and/or wetlands. Molluscs uptake local water during their growing season (spring and summer) and incorporate its delta 180 signature into their shells. Preliminary 180 analysis of modem shells from the southern Great Basin indicates that the shells probably reflect meteoric water 180 values during the growing season. This provides a way to estimate the delta 180 value of precipitation and, thereby, the source of the moisture-bearing air masses. Significant 180 variability in shells analyzed include geographic location, elevation, taxonomy, and habitat (terrestrial, spring, or wetland). We found a rough inverse correlation with elevation in modem shells from the Spring Range in southern Nevada. The delta 180 values of modem and fossil shells are also very different; modem values in this location are much higher than those from nearby late Pleistocene-age molluscs suggesting that the Pleistocene summers were variously colder and wetter than today or less evaporative (more humid). Assuming shell material directly reflects the 180 of the growing-season environment, comparison of modem and fossil shell delta 180 values can potentially identify changes in air-mass moisture sources and can help to define seasonal precipitation change through time. Comprehension and quantification of community and isotopic variability in modem gastropods is required to create probabilistic valid transfer functions with fossil materials. Valid inferences about past environmental conditions can then be established with known confidence limits.

  12. CRCP-Acropora palmata snail corallivore removal evaluation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Corallivorous snail feeding scars are a common source of tissue loss for the threatened coral Acropora palmata, accounting for roughly one quarter of tissue loss in...

  13. The Secrets Behind Vegetation Control on Snail Fever

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Oncomelania (Oncomelania hupensis), a dioecian, ovoviviparous, and amphibious snail, is the sole intermediate host of Schistosoma japonicum, the most wide-spread snail fever in the world. Chemical eliminating the host proved unacceptable for there was severe contamination to water and soil. The river beaches and the delta areas of five provinces in the middle and lower reaches of Yangtze River in China provide the most favorable habitats for Oncomelania. Our studies have revealed that the occurrence of ...

  14. Microhabitats within Venomous Cone Snails Contain Diverse Actinobacteria▿ †

    OpenAIRE

    Peraud, Olivier; Biggs, Jason S.; Hughen, Ronald W.; Alan R. Light; Concepcion, Gisela P.; Baldomero M. Olivera; Schmidt, Eric W.

    2009-01-01

    Actinomycetes can be symbionts in diverse organisms, including both plants and animals. Some actinomycetes benefit their host by producing small molecule secondary metabolites; the resulting symbioses are often developmentally complex. Actinomycetes associated with three cone snails were studied. Cone snails are venomous tropical marine gastropods which have been extensively examined because of their production of peptide-based neurological toxins, but no microbiological studies have been rep...

  15. Molluscicidal activity of Physalis angulata L. extracts and fractions on Biomphalaria tenagophila (d'Orbigny, 1835) under laboratory conditions

    OpenAIRE

    José Augusto A dos Santos; Therezinha Coelho B Tomassini; Deise Cristina Drummond Xavier; Ivone Maria Ribeiro; Melissa Teixeira G da Silva; Zenildo Buarque de Morais Filho

    2003-01-01

    The main objective of this research is to evaluate the molluscicide activity of Physalis angulata L. Biomphalaria tenagophila specimens under laboratory conditions. Extracts and fractions were supplied by the Laboratório de Química de Produtos Naturais, Farmanguinhos-Fiocruz. Experiments were performed according to the methodology described by the World Health Organization for molluscicide tests using the concentrations from 0.1 to 500 mg/l of the extracts, fractions and of a pool of physalin...

  16. Evidence for exploitative interspecific competition in mud snails (Hydrobiidae)

    International Nuclear Information System (INIS)

    Some of the basic assumptions implied in the theory of limiting similarity of coexisting competitors were investigated experimentally in the case of three congeneric, deposit feeding snails. The species show character displacement with respect to size when coexisting. In experimental containers with a natural substrate, interspecific, exploitative competition between snails of the same size range is as intense as intraspecific competition. Diatoms of a given size range, which constitute the most important food, show a ''logistic'' growth response to grazing, and individual growth of the snails is linearly related to diatom density. The previous observation that the snails show size dependent selection for ingested particle sizes is extended to show that this mechanism leads to a real resource partitioning between snails of different sizes. Size frequency distribution of diatoms in the sediment is a function of the sizes of grazing snails. Size selection of ingested sand grains may also be significant for resource partitioning since the migration rate of the attached microflora between sand grains seems to be slow relative to its growth on the individual sand grains. (author)

  17. Synergistic effects of tacrolimus and azole antifungal compounds in fluconazole-susceptible and fluconazole-resistant Candida glabrata isolates

    Directory of Open Access Journals (Sweden)

    Laura Bedin Denardi

    2015-03-01

    Full Text Available In vitro interaction between tacrolimus (FK506 and four azoles (fluconazole, ketoconazole, itraconazole and voriconazole against thirty clinical isolates of both fluconazole susceptible and -resistant Candida glabrata were evaluated by the checkerboard microdilution method. Synergistic, indifferent or antagonism interactions were found for combinations of the antifungal agents and FK506. A larger synergistic effect was observed for the combinations of FK506 with itraconazole and voriconazole (43%, followed by that of the combination with ketoconazole (37%, against fluconazole-susceptible isolates. For fluconazole-resistant C. glabrata, a higher synergistic effect was obtained from FK506 combined with ketoconazole (77%, itraconazole (73%, voriconazole (63% and fluconazole (60%. The synergisms that we observed in vitro, notably against fluconazole-resistant C. glabrata isolates, are promising and warrant further analysis of their applications in experimental in vivo studies.

  18. Candida glabrata among Candida spp. from environmental health practitioners of a Brazilian Hospital

    OpenAIRE

    Catarina Savastano; Elisa de Oliveira Silva; Lindyanne Lemos Gonçalves; Jéssica Maria Nery; Naiara Chaves Silva; Amanda Latercia Tranches Dias

    2016-01-01

    Abstract The incidence of the species Candida albicans and non-albicans Candida was evaluated in a Brazilian Tertiary Hospital from the environment and health practitioners. In a 12-month period we had a total positivity of 19.65% of Candida spp. The most recurring non-albicans Candida species was C. glabrata (37.62%), generally considered a species of low virulence, but with a higher mortality rate than C. albicans. Subsequently, C. parapsilosis (25.74%) and C. tropicalis (16.86%) were the s...

  19. Differential expression of Snail1 transcription factor and Snail1-related genes in alveolar and embryonal rhabdomyosarcoma subtypes

    Directory of Open Access Journals (Sweden)

    Miroslawa Püsküllüoglu

    2010-04-01

    Full Text Available Rhabdomyosarcoma (RMS represents the most common sarcoma of soft tissue among children. Two main RMSsubtypes are alveolar (ARMS and embryonal (ERMS. The major goal of this study was to find differentially expressedgenes between RMS subtypes that could explain higher metastatic potential in ARMS and would be useful for the differentialdiagnosis. Using RQ-PCR analysis we compared expression of Snail1 and Snail-related genes among 7 ARMS and 8ERMS patients' samples obtained from the primary tumors and among 2 alveolar and 2 embryonal cell lines. Our resultsshow that Snail1 is highly expressed both in ARMS patients' samples and the alveolar cell lines. We also found that theexpression of E-Cadherin was downregulated and the expression of Matrix Metalloproteinases 2 and 9 (MMP-2 and MMP-9 was upregulated in ARMS. We assume that, as in many tumors, also in RMS Snail1 acts as a regulator for pathwaysknown for their role in cells' metastasis and that Snail1 activity results in increased MMPs and decreased E-Cadherin expression.Our findings may explain higher ARMS aggressiveness. Moreover, we suggest that further studies should be performedto verify if Snail1 can be considered as a potential target for ARMS therapy.

  20. Transmission studies of intestinal schistosomiasis in Lake Albert, Uganda and experimental compatibility of local Biomphalaria spp

    DEFF Research Database (Denmark)

    Kazibwe, F.; Makanga, B.; Rubaire-Akiiki, C.;

    2010-01-01

    Despite ongoing preventive chemotherapy campaigns, intestinal schistosomiasis is hyper-endemic in shoreline communities living along Lake Albert, Uganda. To provide a deeper insight into the local epidemiology of Schistosoma mansoni, a variety of field-based studies were undertaken focusing upon ...... environmental modification(s), i.e. improvement in sanitation and hygiene and control of snail populations, is needed to bolster the impact of chemotherapy-based interventions....

  1. The molluscicidal activity of coumarins from Ethulia conyzoides and of dicumarol

    DEFF Research Database (Denmark)

    Kady, M M; Brimer, L; Furu, P;

    1992-01-01

    The molluscicidal principles of Ethulia conyzoides were identified as ethuliacoumarin A (1) and isoethuliacoumarin A (2). Ethuliacoumarin A possessed an LC90 between 19 and 23.5 ppm depending on the age of the snail against Biomphalaria glabrata, and between 12 and 15 ppm against Bulinus truncatus....... In addition, ethuliacoumarin A was found to be cercaricidal at 25 ppm and ovicidal. Ethuliacoumarin has the structural requirements considered essential for anticoagulant activity. Consequently the anticoagulant dicumarol (4) was tested and found to be molluscicidal in the range from 2.5 to 10 ppm....... In contrast, the coumarin anticoagulant warfarin (3) did not show molluscicidal activity....

  2. Candida glabrata tryptophan-based pigment production via the Ehrlich pathway.

    Science.gov (United States)

    Brunke, Sascha; Seider, Katja; Almeida, Ricardo Sergio; Heyken, Antje; Fleck, Christian Benjamin; Brock, Matthias; Barz, Dagmar; Rupp, Steffen; Hube, Bernhard

    2010-04-01

    Pigments contribute to the pathogenicity of many fungi, mainly by protecting fungal cells from host defence activities. Here, we have dissected the biosynthetic pathway of a tryptophan-derived pigment of the human pathogen Candida glabrata, identified key genes involved in pigment production and have begun to elucidate the possible biological function of the pigment. Using transcriptional analyses and a transposon insertion library, we have identified genes associated with pigment production. Targeted deletion mutants revealed that the pigment is a by-product of the Ehrlich pathway of tryptophan degradation: a mutant lacking a tryptophan-upregulated aromatic aminotransferase (Aro8) displayed significantly reduced pigmentation and a recombinantly expressed version of this protein was sufficient for pigment production in vitro. Pigment production is tightly regulated as the synthesis is affected by the presence of alternative nitrogen sources, carbon sources, cyclic AMP and oxygen. Growth of C. glabrata on pigment inducing medium leads to an increased resistance to hydrogen peroxide, an effect which was not observed with a mutant defective in pigmentation. Furthermore, pigmented yeast cells had a higher survival rate when exposed to human neutrophils and caused increased damage in a monolayer model of human epithelia, indicating a possible role of pigmentation during interactions with host cells. PMID:20199593

  3. Anacardic acid: molluscicide in cashew nut shell liquid.

    Science.gov (United States)

    Sullivan, J T; Richards, C S; Lloyd, H A; Krishna, G

    1982-03-01

    The components of anacardic acid, (a mixture of 6-n-C (15) alkylsalicylic acids whose side chains vary in degrees of unsaturation) have been isolated by high pressure liquid chromatography from a crude extract of cashew nut shell, Anacardium occidentale, and tested for toxicity to fresh water snails, Biomphalaria glabrata. The triene component is the most toxic form (LC (50) 0.35 ppm), the diene and monoene components are less toxic (LC (50) 0.9 and 1.4 ppm), and the saturated component is relatively nontoxic (LC (50) > 5 ppm). Since decarboxylated anacardic acid (cardanol) and salicylic acid do not kill snails at concentrations up to 5 ppm, it appears that both, carboxyl group and unsaturated side chain are absolutely required for molluscicidal activity. The mechanism of toxicity of anacardic acid to snails is unknown. PMID:17402106

  4. A study of the larvicidal and molluscicidal activities of some medicinal plants from northeast Brazil.

    Science.gov (United States)

    de S Luna, J; dos Santos, A F; de Lima, M R F; de Omena, M C; de Mendonça, F A C; Bieber, L W; Sant'Ana, A E G

    2005-02-28

    In a search for natural products that could be used to control the vectors of tropical diseases, 23 extracts of medicinal plants from the northeast of Brazil have been tested for molluscicidal activity against egg masses and adults of the snail Biomphalaria glabrata, for larvicidal activity against the larvae of the mosquito Aedes aegypti, and for general toxicity against the larvae of the brine shrimp Artemia salina. Of these extracts, two were active against the adult snail, one against snail egg masses, eight against the larvae of the mosquito, and 16 showed toxicity towards the brine shrimp. Chemical tests indicated that a wide variety of natural product classes were present in those extracts that showed significant activities in the bioassays. PMID:15707752

  5. Identification of planorbids from Venezuela by polymerase chain reaction amplification and restriction fragment length polymorphism of internal transcriber spacer of the RNA ribosomal gene

    Directory of Open Access Journals (Sweden)

    Caldeira Roberta L

    2000-01-01

    Full Text Available Snails of the genus Biomphalaria from Venezuela were subjected to morphological assessment as well as polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP analysis. Morphological identification was carried out by comparison of characters of the shell and the male and female reproductive apparatus. The PCR-RFLP involved amplification of the internal spacer region ITS1 and ITS2 of the RNA ribosomal gene and subsequent digestion of this fragment by the restriction enzymes DdeI, MnlI, HaeIII and MspI. The planorbids were compared with snails of the same species and others reported from Venezuela and present in Brazil, Cuba and Mexico. All the enzymes showed a specific profile for each species, that of DdeI being the clearest. The snails were identified as B. glabrata, B. prona and B. kuhniana.

  6. Helix and Drugs: Snails for Western Health Care From Antiquity to the Present

    OpenAIRE

    Bruno Bonnemain

    2005-01-01

    The land helix, or snail, has been used in medicine since antiquity and prepared according to several formulations. This historical report traces the understanding of their properties from the time of Hippocrates, who proposed the use of snail mucus against protoccle and Pliny who thought that the snail increased the speed of delivery and was “a sovereign remedy to treat pain related to burns, abscesses and other wounds”, Galien recommended snails against hydrops foetails. In the 18th centu...

  7. Land snails (Mollusca: Gastropoda) of India: status, threats and conservation strategies

    OpenAIRE

    Sen, S.; Ravikanth, G; N.A. Aravind

    2012-01-01

    Land snails form an important component in the forest ecosystem. In terms of number of species, the phylum Mollusca, to which land snails belong, is the largest phylum after Arthropoda. Mollusca provide unique ecosystem services including recycling of nutrients and they provide a prey base for small mammals, birds, snakes and other reptiles. However, land snails have the largest number of documented extinctions, compared to any other taxa. Till date 1,129 species of land snails are recorde...

  8. Fasciola hepatica in Snails Collected from Water-Dropwort Fields using PCR

    OpenAIRE

    Kim, Hwang-Yong; Choi, In-Wook; Kim, Yeon-Rok; Quan, Juan-Hua; Ismail, Hassan Ahmed Hassan Ahmed; Cha, Guang-Ho; Hong, Sung-Jong; Lee, Young-Ha

    2014-01-01

    Fasciola hepatica is a trematode that causes zoonosis mainly in cattle and sheep and occasionally in humans. Fascioliasis has been reported in Korea; however, determining F. hepatica infection in snails has not been done recently. Thus, using PCR, we evaluated the prevalence of F. hepatica infection in snails at 4 large water-dropwort fields. Among 349 examined snails, F. hepatica-specific internal transcribed space 1 (ITS-1) and/or ITS-2 markers were detected in 12 snails and confirmed using...

  9. ATM-mediated Snail Serine 100 phosphorylation regulates cellular radiosensitivity

    International Nuclear Information System (INIS)

    Purpose: Activation of the DNA damage responsive protein kinase ATM is a critical step for cellular survival in response to ionizing irradiation (IR). Direct targets of ATM regulating radiosensitivity remain to be fully investigated. We have recently reported that ATM phosphorylates the transcriptional repressor Snail on Serine 100. We aimed to further study the functional significance of ATM-mediated Snail phosphorylation in response to IR. Material and methods: We transfected vector-only, wild-type, the Serine 100 to alanine (S100A) or to glutamic acid (S100E) substitution of Snail into various cell lines. We assessed colony formation, γ-H2AX focus formation and the invasion index in the cells treated with or without IR. Results: We found that over-expression of the S100A mutant Snail in HeLa cells significantly increased radiosensitivity. Meanwhile the expression of S100E, a phospho-mimicking mutation, resulted in enhanced radio-resistance. Interestingly, S100E could rescue the radiosensitive phenotype in ATM-deficient cells. We also found that expression of S100E increased γ-H2AX focus formation and compromised inhibition of invasion in response to IR independent of cell survival. Conclusion: ATM-mediated Snail Serine 100 phosphorylation in response to IR plays an important part in the regulation of radiosensitivity

  10. In vitro activity of essential oils extracted from condiments against fluconazole-resistant and -sensitive Candida glabrata.

    Science.gov (United States)

    Soares, I H; Loreto, É S; Rossato, L; Mario, D N; Venturini, T P; Baldissera, F; Santurio, J M; Alves, S H

    2015-09-01

    In the present study, the antifungal activity of essential oils obtained from Origanum vulgare (oregano), Cinnamomum zeylanicum (cinnamon), Lippia graveolens (Mexican oregano), Thymus vulgaris (thyme), Salvia officinalis (sage), Rosmarinus officinalis (rosemary), Ocimum basilicum (basil) and Zingiber officinale (ginger) were assessed against Candida glabrata isolates. One group contained 30 fluconazole-susceptible C. glabrata isolates, and the second group contained fluconazole-resistant isolates derived from the first group after the in vitro induction of fluconazole-resistance, for a total of 60 tested isolates. The broth microdilution methodology was used. Concentrations of 50μg/mL, 100μg/mL, 200μg/mL, 400μg/mL, 800μg/mL, 1600μg/mL and 3200μg/mL of the essential oils were used, and the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined. Thyme, sage, rosemary, basil and ginger essential oils showed no antifungal activity at the tested concentrations. Antimicrobial activity less than or equal to 3200μg/mL was observed for oregano, Mexican oregano and cinnamon essential oils. Both the oregano and Mexican oregano essential oils showed high levels of antifungal activity against the fluconazole-susceptible C. glabrata group, whereas the cinnamon essential oil showed the best antifungal activity against the fluconazole-resistant C. glabrata isolates. PMID:26281965

  11. Genotypic variation in host response to infection affects parasite reproductive rate.

    Science.gov (United States)

    Tavalire, Hannah F; Blouin, Michael S; Steinauer, Michelle L

    2016-02-01

    Parasite fitness is largely influenced by a variation in host response due to the host's genetic background. Here we investigated the impact of host genotype on pathogen success in the snail vector of its castrating parasite, Schistosoma mansoni. We infected five inbred lines of Biomphalaria glabrata with two infection doses and followed their growth, reproductive output and parasite production throughout the course of infection. There was no difference in resistance to infection among inbred lines, but lines varied in their responses to infection and the numbers of parasites produced. Snails did not compensate for castration by increasing their fecundity during the early phase of infection (fecundity compensation). However, some lines were able to delay parasite shedding for up to 30 weeks, thus prolonging reproduction before the onset of castration. Here we propose this strategy as a novel defense against castrating pathogens in snails. Gigantism, a predicted outcome of castration due to energy reallocation, occurred early in infection (cercariae within a single 2h shedding period, resulting in a total production of 6981-29,509 cercariae over the lifetime of a single snail. Regardless of genetic background, snail size was a strong predictor of parasite reproduction: each millimetre increase in snail size at the time of the first shed resulted in up to 3500 more cercariae over the lifetime of the snail. The results of this study provide a detailed picture of variation in hosts' responses to infection and the resulting impacts on parasite fitness, further defining the intricacies of snail-schistosome compatibility. PMID:26552016

  12. Helix and Drugs: Snails for Western Health Care From Antiquity to the Present

    Directory of Open Access Journals (Sweden)

    Bruno Bonnemain

    2005-01-01

    Full Text Available The land helix, or snail, has been used in medicine since antiquity and prepared according to several formulations. This historical report traces the understanding of their properties from the time of Hippocrates, who proposed the use of snail mucus against protoccle and Pliny who thought that the snail increased the speed of delivery and was “a sovereign remedy to treat pain related to burns, abscesses and other wounds”, Galien recommended snails against hydrops foetails. In the 18th century, various snail “preparations” were also recommended for external use with dermatological disorders and internally for symptoms associated with tuberculosis and nephritis. Surprisingly, the 19th century saw a renewed interest in the pharmaceutical and medical use of snails with numerous indications for snail preparations. This interest in snails did not stop at the end of the 19th century. The 1945 edition of Dorvault devotes an entire paragraph to snails, indicating that the therapeutic usage of snails was still alive at that time. Recently the FDA has also shown an interest in snails. Ziconotide (SNXIII, a synthetic peptide coming from snail venom, has been under FDA review since 1999. Pre-clinical and clinical studies of this new drug are promising.

  13. MTA3 regulates CGB5 and Snail genes in trophoblast

    International Nuclear Information System (INIS)

    Highlights: •Impaired MTA3, raised CGB5 and Snail expression are associated with preeclampsia. •Knock-down of MTA3 causes up-regulation of CGB5 and Snail genes in BeWo cells. •MTA3 occupies CGB5 and Snail gene promoters in BeWo cells. -- Abstract: Secreted by the placental trophoblast, human chorionic gonadotropin (hCG) is an important hormone during pregnancy and is required for the maintenance of pregnancy. Previous studies have shown that dys-regulation of hCG expression is associated with preeclampsia. However, the exact relationship between altered hCG levels and development of preeclampsia is unknown. Metastasis associated protein 3 (MTA3), a chromatin remodeling protein, is abundantly expressed in the placental trophoblasts, but its function is unknown. In breast cancer, MTA3 has been shown to repress the expression of Snail and cell migration. However, whether MTA3 acts similarly in the trophoblast has not been investigated. In the present study, we examined the role of MTA3 in regulating the hCG β-subunit gene (gene name: CGB5) and Snail expression in the trophoblast cell line, BeWo, as well as its relevance to the high hCG expression levels seen in preeclampsia. First, we investigated MTA3 expression in preeclamptic placenta as compared to normal control placenta via gene expression microarray and qRT-PCR and found that MTA3 was significantly down-regulated, whereas both CGB5 and Snail were up-regulated in preeclamptic placenta. Secondly, we knocked down MTA3 gene in trophoblast cell line BeWo and found Snail and hCG were both up-regulated, suggesting that MTA3 represses Snail and hCG gene expression in trophoblasts. Next, we cloned the CGB5 and Snail promoters into the pGL3-basic vector individually and found that silencing of MTA3 by siRNA resulted in an increase of both CGB5 and Snail promoter activities. To confirm that this MTA3 inhibition is a direct effect, we performed a chromatin immune-precipitation (ChIP) assay and found that MTA3

  14. MTA3 regulates CGB5 and Snail genes in trophoblast

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, MI 49503 (United States); Miyazaki, Jun [Department of Obstetrics and Gynecology, Fujita Health University School of Medicine, Fujita Health University, Toyoake (Japan); Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake (Japan); Nishizawa, Haruki [Department of Obstetrics and Gynecology, Fujita Health University School of Medicine, Fujita Health University, Toyoake (Japan); Kurahashi, Hiroki [Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake (Japan); Leach, Richard, E-mail: Richard.Leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group, Grand Rapids, MI 49503 (United States); Wang, Kai, E-mail: Kai.Wang@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, MI 49503 (United States)

    2013-04-19

    Highlights: •Impaired MTA3, raised CGB5 and Snail expression are associated with preeclampsia. •Knock-down of MTA3 causes up-regulation of CGB5 and Snail genes in BeWo cells. •MTA3 occupies CGB5 and Snail gene promoters in BeWo cells. -- Abstract: Secreted by the placental trophoblast, human chorionic gonadotropin (hCG) is an important hormone during pregnancy and is required for the maintenance of pregnancy. Previous studies have shown that dys-regulation of hCG expression is associated with preeclampsia. However, the exact relationship between altered hCG levels and development of preeclampsia is unknown. Metastasis associated protein 3 (MTA3), a chromatin remodeling protein, is abundantly expressed in the placental trophoblasts, but its function is unknown. In breast cancer, MTA3 has been shown to repress the expression of Snail and cell migration. However, whether MTA3 acts similarly in the trophoblast has not been investigated. In the present study, we examined the role of MTA3 in regulating the hCG β-subunit gene (gene name: CGB5) and Snail expression in the trophoblast cell line, BeWo, as well as its relevance to the high hCG expression levels seen in preeclampsia. First, we investigated MTA3 expression in preeclamptic placenta as compared to normal control placenta via gene expression microarray and qRT-PCR and found that MTA3 was significantly down-regulated, whereas both CGB5 and Snail were up-regulated in preeclamptic placenta. Secondly, we knocked down MTA3 gene in trophoblast cell line BeWo and found Snail and hCG were both up-regulated, suggesting that MTA3 represses Snail and hCG gene expression in trophoblasts. Next, we cloned the CGB5 and Snail promoters into the pGL3-basic vector individually and found that silencing of MTA3 by siRNA resulted in an increase of both CGB5 and Snail promoter activities. To confirm that this MTA3 inhibition is a direct effect, we performed a chromatin immune-precipitation (ChIP) assay and found that MTA3

  15. Study on gamma irradiation of snail slime for cosmetic applications

    International Nuclear Information System (INIS)

    Snail slime is a product used by the cosmetic industry for skin regeneration. Due to its origin and obtaining method, prior to be commercialized, it requires to be exposed to a decontaminated procedure. Samples of snail slime were provided by the manufacturer and were treated with gamma irradiation doses of 2, 3 and 5 kGy. Microbiological, physico-chemical and organoleptic tests, indicated by the product specifications, were performed to the irradiated and control samples in order to determine the optimal decontamination dose. IR spectra of the irradiated samples and control were also obtained. It was determined that the minimum dose of 3 kGy was enough to achieve decontamination of the product without significant changes of the physico-chemical properties. Likewise, at 3 kGy, appearance, color and odour of snail slime remained almost unchanged. (author)

  16. Some quality parameters of land snail meat - Helix pomatia

    Directory of Open Access Journals (Sweden)

    Tojagić Slobodan N.

    2004-01-01

    Full Text Available Considering the tradition in our regions to collect land snails (Helix pomatia for export, which is "disrupted" by social control resulting in limited possibilities to develop this attractive activity, there is a great interest lately for land snail breeding and fattening at farms. For this reason it is necessary to investigate systematically the possibilities to develop this activity in a longer period and in larger areas. The first investigations, although covering only nutritive and health safety aspects of the edible parts yielded the results presented in this work. Chemical composition, the content of some elements and organochlorine insecticides were followed as unavoidable in human living and environment.

  17. Effect of radiation on Lymnnea auricularia rubiginosa snails

    International Nuclear Information System (INIS)

    As a means of checking the spread of fascioliasis, the intermediate host of F. hepatica and F. gigantica which is the Lumnea auricularia rubiginosa is exposed to different doses of radioisotopes. Radioisotopes used were 32P, 3H-thymidine, and 137Cs. Findings show that at different concentration and doses of radioisotopes, there is a reduced viability and increase mortality in the eggs laid by the parent snails exposed to radiation. The effects on the development of irradiated eggs are also being studied as well as the effects of irradiation on the reproductive apparatus of the snails

  18. Screening of Malian medicinal plants for antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities.

    Science.gov (United States)

    Diallo, D; Marston, A; Terreaux, C; Touré, Y; Paulsen, B S; Hostettmann, K

    2001-08-01

    A total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from Mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. Dichloromethane, methanol, water and ethanol extracts were used. TLC autobiography for antifungal activity was run with Cladosporium cucumerinum and Candida albicans. Extracts were also tested on the larvae of the mosquitoes Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molluscicidal activities were established with the snails Biomphalaria glabrata, Biomphalaria pfeifferi and Bulinus truncatus. beta-Carotene and DPPH solutions sprayed on TLC plates were used for antioxidant and radical scavenging assays. Of the extracts investigated, 20% were antioxidant and radical scavengers, 19% fungicidal, 30% were larvicidal and 11% were molluscicidal. Three of the plant extracts, from Cussonia barteri (Araliaceae), Glinus oppositifolius (Aïzoaceae) and Lannea velutina (Anacardiaceae) gave positive responses in all four tests. PMID:11507731

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

    Directory of Open Access Journals (Sweden)

    Janira Lúcia Assumpção Couto

    2005-08-01

    mesoregion of the Agreste Alagoano. The snails collected for analysis came from different types of habitats, namely streams, springs, ditches, dams, swamps, wells and ponds. The snails were collected from February 1996 through December 1998. The identification of Biomphalaria glabrata was made through anatomical analysis of the soft inner parts of the snails after having been removed their shells. As for the detection of cercariae of Schistosoma mansoni, the crush technique was applied in order to calculate the percentage of infection rates. Among the areas surveyed, 32 municipalities (80% of the total, presented the species Biomphalaria glabrata, six of which containing snails infected with cercariae of the parasite. Penedo presented the highest infection rate (6.6%, followed by Ibateguara (5.6%. Lower rates were noticed in Chã Preta (2.7%, in Murici (2.5%, Porto Real do Colégio (0.1% and Igreja Nova (0.1%.The coproparasitologic analyses conducted at the Fundação Nacional de Saúde in 1997, 1998/1999 and 2000, confirmed the importance of schistosomiasis mansoni in the areas surveyed in this work.

  20. Efficacy of euphorbia hirta latex as plant derived molluscicides against freshwater snails

    Directory of Open Access Journals (Sweden)

    Ram P. Yadav

    2011-04-01

    Full Text Available The toxic effect of binary and tertiary combinations of Euphorbia hirta Linn latex powder with other plant molluscicidal compounds, were evaluated against the freshwater snails Lymnaea (Radix acuminata and Indoplanorbis exustus in pond. These combinations showed significant time and dose dependent effect against both the snails. These compounds at higher doses were also lethal to freshwater fish Channa punctatus (Bloch (Channidae {Ophicephalidae}, which shares the habitat with these snails, but the LC90 (24h doses of snails have no apparent killing properties in fish populations when treated in mixed population of snails and fish.

  1. Formation of new chromosomes as a virulence mechanism in yeast Candida glabrata

    DEFF Research Database (Denmark)

    Poláková, S.; Blume, C.; Zárate, J. A.;

    2009-01-01

    chromosomes were translocations of chromosomal arms. However, also larger segmental duplications were frequent and occasionally we observed novel chromosomes. Apparently, this yeast can generate a new chromosome by duplication of chromosome segments carrying a centromere and subsequently adding novel......In eukaryotes, the number and rough organization of chromosomes is well preserved within isolates of the same species. Novel chromosomes and loss of chromosomes are infrequent and usually associated with pathological events. Here, we analyzed 40 pathogenic isolates of a haploid and asexual yeast......, Candida glabrata, for their genome structure and stability. This organism has recently become the second most prevalent yeast pathogen in humans. Although the gene sequences were well conserved among different strains, their chromosome structures differed drastically. The most frequent events reshaping...

  2. Nuclear ubiquitination by FBXL5 modulates Snail1 DNA binding and stability.

    Science.gov (United States)

    Viñas-Castells, Rosa; Frías, Álex; Robles-Lanuza, Estefanía; Zhang, Kun; Longmore, Gregory D; García de Herreros, Antonio; Díaz, Víctor M

    2014-01-01

    The zinc finger transcription factor Snail1 regulates epithelial to mesenchymal transition, repressing epithelial markers and activating mesenchymal genes. Snail1 is an extremely labile protein degraded by the cytoplasmic ubiquitin-ligases β-TrCP1/FBXW1 and Ppa/FBXL14. Using a short hairpin RNA screening, we have identified FBXL5 as a novel Snail1 ubiquitin ligase. FBXL5 is located in the nucleus where it interacts with Snail1 promoting its polyubiquitination and affecting Snail1 protein stability and function by impairing DNA binding. Snail1 downregulation by FBXL5 is prevented by Lats2, a protein kinase that phosphorylates Snail1 precluding its nuclear export but not its polyubiquitination. Actually, although polyubiquitination by FBXL5 takes place in the nucleus, Snail1 is degraded in the cytosol. Finally, FBXL5 is highly sensitive to stress conditions and is downregulated by iron depletion and γ-irradiation, explaining Snail1 stabilization in these conditions. These results characterize a novel nuclear ubiquitin ligase controlling Snail1 protein stability and provide the molecular basis for understanding how radiotherapy upregulates the epithelial to mesenchymal transition-inducer Snail1. PMID:24157836

  3. Dry down impacts on apple snail (Pomacea paludosa) demography: Implications for wetland water management

    Science.gov (United States)

    Darby, P.C.; Bennetts, R.E.; Percival, H.F.

    2008-01-01

    Florida apple snails (Pomacea paludosa Say) are prey for several wetland-dependent predators, most notably for the endangered Florida snail kite (Rostrhamus sociabilis Vieillot). Management concerns for kites have been raised regarding the impacts of wetland dry downs on snails, but little data exists to validate these concerns. We simulated drying events in experimental tanks, where we observed that snail survival patterns, regardless of hydrology, were driven by a post-reproductive die off. In contrast to earlier reports of little to no dry down tolerance, we found that 70% of pre-reproductive adult-sized snails survived a 12-week dry down. Smaller size classes of snails exhibited significantly lower survival rates (apple snail populations, and illustrate why multiple characteristics of dry down events should be considered in developing target hydrologic regimes for wetland fauna. ?? 2008, The Society of Wetland Scientists.

  4. The redial and cercarial production of a Digenean in the snail host is lower when no cercarial shedding occurs

    OpenAIRE

    Dreyfuss G.; Vignoles P.; Rondelaud D.

    2009-01-01

    Single- and double-miracidium exposures of Galba truncatula with Fasciola hepatica (two groups) or with Paramphistomum daubneyi (two groups) were carried out under laboratory conditions to compare parasite production in cercaria-shedding snails (CS snails) with that found in snails without emission (NCS snails). Free rediae and cercariae were thus counted in snails from both categories after their dissection at regular intervals (at 24 °C). In the four groups, the numbers of free rediae and f...

  5. A snail-eating snake recognizes prey handedness.

    Science.gov (United States)

    Danaisawadi, Patchara; Asami, Takahiro; Ota, Hidetoshi; Sutcharit, Chirasak; Panha, Somsak

    2016-01-01

    Specialized predator-prey interactions can be a driving force for their coevolution. Southeast Asian snail-eating snakes (Pareas) have more teeth on the right mandible and specialize in predation on the clockwise-coiled (dextral) majority in shelled snails by soft-body extraction. Snails have countered the snakes' dextral-predation by recurrent coil reversal, which generates diverse counterclockwise-coiled (sinistral) prey where Pareas snakes live. However, whether the snake predator in turn evolves any response to prey reversal is unknown. We show that Pareas carinatus living with abundant sinistrals avoids approaching or striking at a sinistral that is more difficult and costly to handle than a dextral. Whenever it strikes, however, the snake succeeds in predation by handling dextral and sinistral prey in reverse. In contrast, P. iwasakii with little access to sinistrals on small peripheral islands attempts and frequently misses capturing a given sinistral. Prey-handedness recognition should be advantageous for right-handed snail-eating snakes where frequently encountering sinistrals. Under dextral-predation by Pareas snakes, adaptive fixation of a prey population for a reversal gene instantaneously generates a sinistral species because interchiral mating is rarely possible. The novel warning, instead of sheltering, effect of sinistrality benefitting both predators and prey could further accelerate single-gene ecological speciation by left-right reversal. PMID:27046345

  6. Molecular diversity of avian schistosomes in Danish freshwater snails.

    Science.gov (United States)

    Christiansen, Anne Ø; Olsen, Annette; Buchmann, Kurt; Kania, Per W; Nejsum, Peter; Vennervald, Birgitte J

    2016-03-01

    Avian schistosomes are widespread parasites of snails and waterfowl and may cause cercarial dermatitis (swimmer's itch) in humans, a disease that is frequently reported in European countries. These parasites are known to occur in Denmark, but here, we applied a new approach using molecular tools to identify the parasites at species level. In order to do that, 499 pulmonate freshwater snails (Radix sp., Lymnaea stagnalis, Stagnicola sp. and Planorbarius corneus) were sampled from 12 lakes, ponds, and marshes in the greater Copenhagen area. Avian schistosome cercariae were identified by microscopy and subjected to molecular investigation by sequencing and phylogenetic analysis of the 5.8S and ITS2 ribosomal DNA for species identification. Additionally, snail hosts belonging to the genus Radix were identified by sequencing and phylogenetic analysis of partial ITS2 ribosomal DNA. Three out of 499 snails shed different species of Trichobilharzia cercariae: Trichobilharzia szidati was isolated from L. stagnalis, Trichobilharzia franki from Radix auricularia and Trichobilharzia regenti from Radix peregra. In the light of the public health risk represented by bird schistosomes, these findings are of concern and, particularly, the presence of the potentially neuro-pathogenic species, T. regenti, in Danish freshwaters calls for attention. PMID:26573519

  7. Furcocercous cercariae (Trematoda) from freshwater snails in Central Finland

    OpenAIRE

    Anna Faltynkova; Katarzyna Niewiadomska; Santos, Maria J.; Tellervo T Valtonen

    2007-01-01

    A total of eight species of furcocercous cercariae of four families (Strigeidae, Diplostomidae, Schistosomatidae and Sanguinicolidae), were found in 2005 in Lake Konnevesi in Central Finland in four snail species (Valvata macrostoma, Lymnaea stagnalis, Bathyomphalus contortus and Planorbarius corneus). Australapatemon burti (Miller, 1923), Australapatemon sp., Cotylurus brevis Dubois et Rausch, 1950, Cercaria spinulosa Ginetsinskaya, 1959 and Sanguinicola sp. are new species records for Finla...

  8. A snail-eating snake recognizes prey handedness

    Science.gov (United States)

    Danaisawadi, Patchara; Asami, Takahiro; Ota, Hidetoshi; Sutcharit, Chirasak; Panha, Somsak

    2016-01-01

    Specialized predator-prey interactions can be a driving force for their coevolution. Southeast Asian snail-eating snakes (Pareas) have more teeth on the right mandible and specialize in predation on the clockwise-coiled (dextral) majority in shelled snails by soft-body extraction. Snails have countered the snakes’ dextral-predation by recurrent coil reversal, which generates diverse counterclockwise-coiled (sinistral) prey where Pareas snakes live. However, whether the snake predator in turn evolves any response to prey reversal is unknown. We show that Pareas carinatus living with abundant sinistrals avoids approaching or striking at a sinistral that is more difficult and costly to handle than a dextral. Whenever it strikes, however, the snake succeeds in predation by handling dextral and sinistral prey in reverse. In contrast, P. iwasakii with little access to sinistrals on small peripheral islands attempts and frequently misses capturing a given sinistral. Prey-handedness recognition should be advantageous for right-handed snail-eating snakes where frequently encountering sinistrals. Under dextral-predation by Pareas snakes, adaptive fixation of a prey population for a reversal gene instantaneously generates a sinistral species because interchiral mating is rarely possible. The novel warning, instead of sheltering, effect of sinistrality benefitting both predators and prey could further accelerate single-gene ecological speciation by left-right reversal. PMID:27046345

  9. Spatially-resolved thermoluminescence from snail opercula using an EMCCD

    DEFF Research Database (Denmark)

    Duller, G.A.T.; Kook, Myung Ho; Stirling, R.J.;

    2015-01-01

    In recent years opercula of the snail species Bithynia tentaculata have been shown to emit thermoluminescence (TL) signals that can be used to determine equivalent dose, and may be capable of dating events throughout the entire Quaternary period. Concentric growth lines are a notable feature of a...

  10. Comparative abilities of Candida glabrata and Candida albicans to colonize and translocate from the intestinal tract of antibiotic-treated mice

    OpenAIRE

    Henry-Stanley, Michelle J.; Garni, Robb M.; Johnson, Mary Alice; Bendel, Catherine M.; Wells, Carol L.

    2011-01-01

    Candida albicans is the primary cause of candidemia in hospitalized patients, and the intestinal tract is considered the source of most systemic infections. C. glabrata has emerged as the second or third most frequent cause of candidemia, but little is known about its epidemiology and pathogenesis. Our goal was to compare the intestinal colonization and extra-intestinal dissemination of C. glabrata and C. albicans (wild type and filamentation-defective mutant). Mice were pretreated with antib...

  11. The Use of Golden Snail (Pomacea sp. as Animal Feed in the Philippines

    Directory of Open Access Journals (Sweden)

    Serra, AB.

    1997-01-01

    Full Text Available The golden snail is introduced to the Philippines in early 80's for culture as food source. This herbivorous snail, a voracious feeder of live and fresh plant materials become a serious rice pest. Its elimination in the ecosystems is impossible. To use them as animal feed is much better alternative for their control and more environmentally friendly than the use of chemicals. Thus, this mini review paper aimed to collate any existing information on the use of golden snail as animal feed. The different meal forms that can be extracted are golden snail meal (30 % calcium and 15 % crude protein, golden snail meat meal (62 % crude protein and 3336 kcal/kg and golden shell meal (35 % calcium. Feeding trials indicate that golden snail meal can be a part of swine and chicken layer diets up to 15 %. Golden snail meat meal can be a part of broiler chicken diet up to 12 %. Feeding fresh and ground golden snail to ducks can replace 50 % of their diet under total confinement system. Whereas, golden snail meat meal (75 % of the diet plus rice bran can be beneficially fed to tilapia. With the information collated, golden snail can be a promising animal feed in the Philippines.

  12. Overexpression of Snail in retinal pigment epithelial triggered epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui; Li, Min; Xu, Ding; Zhao, Chun; Liu, Guodong; Wang, Fang, E-mail: milwang_122@msn.com

    2014-03-28

    Highlights: • First reported overexpression of Snail in RPE cells could directly trigger EMT. • Further confirmed the regulator role of Snail in RPE cells EMT in vitro. • Snail may be a potential therapeutic target to prevent the fibrosis of PVR. - Abstract: Snail transcription factor has been implicated as an important regulator in epithelial–mesenchymal transition (EMT) during tumourigenesis and fibrogenesis. Our previous work showed that Snail transcription factor was activated in transforming growth factor β1 (TGF-β1) induced EMT in retinal pigment epithelial (RPE) cells and may contribute to the development of retinal fibrotic disease such as proliferative vitreoretinopathy (PVR). However, whether Snail alone has a direct role on retinal pigment epithelial–mesenchymal transition has not been investigated. Here, we analyzed the capacity of Snail to drive EMT in human RPE cells. A vector encoding Snail gene or an empty vector were transfected into human RPE cell lines ARPE-19 respectively. Snail overexpression in ARPE-19 cells resulted in EMT, which was characterized by the expected phenotypic transition from a typical epithelial morphology to mesenchymal spindle-shaped. The expression of epithelial markers E-cadherin and Zona occludin-1 (ZO-1) were down-regulated, whereas mesenchymal markers a-smooth muscle actin (a-SMA) and fibronectin were up-regulated in Snail expression vector transfected cells. In addition, ectopic expression of Snail significantly enhanced ARPE-19 cell motility and migration. The present data suggest that overexpression of Snail in ARPE-19 cells could directly trigger EMT. These results may provide novel insight into understanding the regulator role of Snail in the development of retinal pigment epithelial–mesenchymal transition.

  13. Overexpression of Snail in retinal pigment epithelial triggered epithelial–mesenchymal transition

    International Nuclear Information System (INIS)

    Highlights: • First reported overexpression of Snail in RPE cells could directly trigger EMT. • Further confirmed the regulator role of Snail in RPE cells EMT in vitro. • Snail may be a potential therapeutic target to prevent the fibrosis of PVR. - Abstract: Snail transcription factor has been implicated as an important regulator in epithelial–mesenchymal transition (EMT) during tumourigenesis and fibrogenesis. Our previous work showed that Snail transcription factor was activated in transforming growth factor β1 (TGF-β1) induced EMT in retinal pigment epithelial (RPE) cells and may contribute to the development of retinal fibrotic disease such as proliferative vitreoretinopathy (PVR). However, whether Snail alone has a direct role on retinal pigment epithelial–mesenchymal transition has not been investigated. Here, we analyzed the capacity of Snail to drive EMT in human RPE cells. A vector encoding Snail gene or an empty vector were transfected into human RPE cell lines ARPE-19 respectively. Snail overexpression in ARPE-19 cells resulted in EMT, which was characterized by the expected phenotypic transition from a typical epithelial morphology to mesenchymal spindle-shaped. The expression of epithelial markers E-cadherin and Zona occludin-1 (ZO-1) were down-regulated, whereas mesenchymal markers a-smooth muscle actin (a-SMA) and fibronectin were up-regulated in Snail expression vector transfected cells. In addition, ectopic expression of Snail significantly enhanced ARPE-19 cell motility and migration. The present data suggest that overexpression of Snail in ARPE-19 cells could directly trigger EMT. These results may provide novel insight into understanding the regulator role of Snail in the development of retinal pigment epithelial–mesenchymal transition

  14. Fluconazole affects the alkali-metal-cation homeostasis and susceptibility to cationic toxic compounds of Candida glabrata

    Czech Academy of Sciences Publication Activity Database

    Elicharová, Hana; Sychrová, Hana

    2014-01-01

    Roč. 160, č. 8 (2014), s. 1705-1713. ISSN 1350-0872 R&D Projects: GA ČR GAP302/12/1151; GA MŠk(CZ) ED1.1.00/02.0109 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : Candida glabrata * fluconazole * membrane potential Subject RIV: EE - Microbiology, Virology Impact factor: 2.557, year: 2014

  15. Determination of quercetin, plumbagin and total flavonoids in Drosera peltata Smith var. glabrata Y.Z.Ruan

    OpenAIRE

    Yu He; Zhimin He; Feng He; Haitong Wan

    2012-01-01

    Background: Drosera peltata Smith var. glabrata Y.Z.Ruan, a kind of wild carnivorous plants in the family Droseraceae, has been used for the treatment of rheumatism and bruises in Chinese folk. None of compounds in this herb has been quantified in the previous studies. Objective: To develop a validated and reliable HPLC method for the simultaneous determination of two bioactive constituents - quercetin and plumbagin, and establish a simple UV spectrophotometry method for the analysis of total...

  16. Probing the Active Site of Candida Glabrata Dihydrofolate Reductase with High Resolution Crystal Structures and the Synthesis of New Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J.; Bolstad, D; Smith, A; Priestley, N; Wright, D; Anderson, A

    2009-01-01

    Candida glabrata, a fungal strain resistant to many commonly administered antifungal agents, has become an emerging threat to human health. In previous work, we validated that the essential enzyme, dihydrofolate reductase, is a drug target in C. glabrata. Using a crystal structure of dihydrofolate reductase from C. glabrata bound to an initial lead compound, we designed a class of biphenyl antifolates that potently and selectively inhibit both the enzyme and the growth of the fungal culture. In this work, we explore the structure-activity relationships of this class of antifolates with four new high resolution crystal structures of enzyme:inhibitor complexes and the synthesis of four new inhibitors. The designed inhibitors are intended to probe key hydrophobic pockets visible in the crystal structure. The crystal structures and an evaluation of the new compounds reveal that methyl groups at the meta and para positions of the distal phenyl ring achieve the greatest number of interactions with the pathogenic enzyme and the greatest degree of selectivity over the human enzyme. Additionally, antifungal activity can be tuned with substitution patterns at the propargyl and para-phenyl positions.

  17. Metabolic acceleration in the pond snail Lymnaea stagnalis?

    Science.gov (United States)

    Zimmer, Elke I.; Ducrot, V.; Jager, T.; Koene, J.; Lagadic, L.; Kooijman, S. A. L. M.

    2014-11-01

    Under constant environmental conditions, most animals tend to grow following the von Bertalanffy growth curve. Deviations from this curve can point to changes in the environment that the animals experience, such as food limitation when the available food is not sufficient or suitable. However, such deviations can also point to a phenomenon called metabolic acceleration, which is receiving increasing attention in the field of Dynamic Energy Budget (DEB) modeling. Reasons for such an acceleration are usually changes in shape during ontogeny, which cause changes in the surface area to volume ratio of the organism. Those changes, in turn, lead to changes in some of the model parameters that have length in their dimension. The life-history consequences of metabolic acceleration as implemented in the DEB theory are an s-shaped growth curve (when body size is expressed as a length measure) and a prolongation of the hatching time. The great pond snail Lymnaea stagnalis was earlier found to be food limited during the juvenile phase in laboratory experiments conducted under classical ecotoxicity test protocols. The pond snail has isomorphic shell growth but yet does not exhibit the expected von Bertalanffy growth curve under food limitation. When applying the standard DEB model to data from such life-cycle experiments, we also found that the hatching time is consistently underestimated, which could be a sign of metabolic acceleration. We here present an application of the DEB model including metabolic acceleration to the great pond snail. We account for the simultaneous hermaphroditism of the snail by including a model extension that describes the relative investment into the male and female function. This model allowed us to adequately predict the life history of the snail over the entire life cycle. However, the pond snail does not change in shape substantially after birth, so the original explanation for the metabolic acceleration does not hold. Since the change in shape

  18. Snail Hosts of Paragonimus in Asia and the Americas

    Institute of Scientific and Technical Information of China (English)

    G.M.DAVIS; CHENCui-E; 等

    1994-01-01

    We have undertaken a comprehensive review of snail hosts of Paragonimus world-wide exclusive of Africa based on modern malacological data,where available,and with consideration of the phylogeny of the snail groups involved.This is the first comprehensive review since those made by Chen(1979)and Chen et al.(1983),and there have been considerable taxonomic changes over the past decade. A number of names and concepts found in the medical malacological and parasitological literature up to the present time require revision or correction.There ae vast radiations of snails of the superfamilies Cerithiacea and Rissoacea involved in the transmission of Paragonimus in CHina.We list 54 species world-wide of which 35(65%)occur in China.Revisions and corrections pertaining to China include:(i)the family Hydrobiidae does not occur in China or S.E.Asia and thd Pomatiopsidae should be used,(ii)The genus Bythinella is entirely European(Hydrobiidae:Amnicolinae).The so-called Bythinella of China belongs to the genus Erhaia(Pomatiopsidae).(iii)The generic name Pseudobythinella described from China is preoccupied,a junior synonym of Pseudobythinella Melville 1956,a fossil from england,ll chinese Pseudobythinella are now classified as Erhaia.(iv)Akiyoshia has been used as a generic name for some snails in Hunan transmitting Paragonimus,Akiyoshia is from Japan and biological/ecological data indicate tat the Chinese taxon is not Akiyoshia.(v)The genus Tricula in recent Chinese literature is comprised of four genera determined by detailed comparative anatomical data:Tricula,Neotricula,Gammatricula,and Jinhongia Shells cannot be used to discriminate among them.(vi)tricula cristella has been consistently misidentified in collections in China and literature.However,genuine T.cristella does transmit Paragonimus skrjabini.(vii)Tricula minutoides in the Chinese literature has been misidentified,and specimens,are T.cristella.(viii)The genus Melania and the family Melaniidae are used in the

  19. A speciation gene for left-right reversal in snails results in anti-predator adaptation.

    Science.gov (United States)

    Hoso, Masaki; Kameda, Yuichi; Wu, Shu-Ping; Asami, Takahiro; Kato, Makoto; Hori, Michio

    2010-01-01

    How speciation genes can spread in a population is poorly understood. In land snails, a single gene for left-right reversal could be responsible for instant speciation, because dextral and sinistral snails have difficulty in mating. However, the traditional two-locus speciation model predicts that a mating disadvantage for the reversal should counteract this speciation. In this study, we show that specialized snake predation of the dextral majority drives prey speciation by reversal. Our experiments demonstrate that sinistral Satsuma snails (Stylommatophora: Camaenidae) survive predation by Pareas iwasakii (Colubroidea: Pareatidae). Worldwide biogeography reveals that stylommatophoran snail speciation by reversal has been accelerated in the range of pareatid snakes, especially in snails that gain stronger anti-snake defense and reproductive isolation from dextrals by sinistrality. Molecular phylogeny of Satsuma snails further provides intriguing evidence of repetitive speciation under snake predation. Our study demonstrates that a speciation gene can be fixed in populations by positive pleiotropic effects on survival. PMID:21139578

  20. Lumican Inhibits SNAIL-Induced Melanoma Cell Migration Specifically by Blocking MMP-14 Activity

    Science.gov (United States)

    Stasiak, Marta; Boncela, Joanna; Perreau, Corinne; Karamanou, Konstantina; Chatron-Colliet, Aurore; Proult, Isabelle; Przygodzka, Patrycja; Chakravarti, Shukti; Maquart, François-Xavier; Kowalska, M. Anna; Wegrowski, Yanusz; Brézillon, Stéphane

    2016-01-01

    Lumican, a small leucine rich proteoglycan, inhibits MMP-14 activity and melanoma cell migration in vitro and in vivo. Snail triggers epithelial-mesenchymal transitions endowing epithelial cells with migratory and invasive properties during tumor progression. The aim of this work was to investigate lumican effects on MMP-14 activity and migration of Snail overexpressing B16F1 (Snail-B16F1) melanoma cells and HT-29 colon adenocarcinoma cells. Lumican inhibits the Snail induced MMP-14 activity in B16F1 but not in HT-29 cells. In Snail-B16F1 cells, lumican inhibits migration, growth, and melanoma primary tumor development. A lumican-based strategy targeting Snail-induced MMP-14 activity might be useful for melanoma treatment. PMID:26930497

  1. Biomphalaria obstructa (Morelet, 1849: a study of topotypic specimens (Mollusca: pulmonata: planorbidae

    Directory of Open Access Journals (Sweden)

    W. Lobato Paraense

    1990-12-01

    Full Text Available A description of Biomphalaria obstructa (Morelet, 1849, based on specimens collected at its type locality - isla del carmen, state of Campeche, Mexico - is presented. The Shell is small, 13 mm in diameter, 3.5 mm in width and with 5.75 whorls in the largest specimen, thin, moderately lustrous and translucent, horn-colored. Whorls increasing regularly (neither slowly nor rapidly in diameter, rounded on the periphery side, bluntly angular on the left. Suture well-marked, deeper on the left. Right side widely concave, with first whorl deeply situated and partly hidden by the next. Left side shallower than right one, largely flattened, with first whorl plaintly visible. Aperture roundly heart-shaped, usually in the same plane as the body whorl but somewhat deflected to the left (less frequently to the right in some specimens. Peristome sharp, seldom blunt; a distinct callus on the parietal wall. A number of young shells develop one set (seldom more of apertural lamellae which tend to be resorbed as the shell grows. Absence of renal ridge. Ovotestis with about 70 mostly unbrached diverticula. Seminal vesicle beset with well-developed knoblike to fingerlike diverticula. Vaginal pouch more or less developed. Spermatheca club-shaped when empty, egg-shaped when full, and with intermediate forms between those extremes. Spermathecal body usually somewhat longer than the duct. Prostate with 7 to 20 (mean 12.06 ± 2.51 usually short diverticula which give off plumpish branches spreading out in a fan shape and overlapping to some extent their immediate neighbors. Foremost prostatic diverticulum nearly always partially or completely inserted between the spermathecal body and the uterine wall. Penial sheath consistently narrower and shorter than the prepuce. Muscular coat of the penis consisting of an inner longitudinal and an outer circular layers. Ratios between organ lengths: caudal to cephalic parts of female duct = 0.55 to 1.37 (mean 0.85 +- 0.17; cephalic

  2. "A Faunistic Survey on the Cercariae of Bellamya (Viviparus) bengalensis Snails and Their Zoonotic Importance"

    OpenAIRE

    H Ghobadi; A Farahnak

    2004-01-01

    Limited studies have been made on the cercariae from freshwater snails in Iran. This study was conducted to determine the cercariae fauna of Bellamya (Viviparus) bengalensis and evaluation of their zoonotic importance in Khuzestan province, south-west of Iran. For this purpose, 1143 Bellamya snails were collected from Ahoudasht region in central areas of the province during 2002-2003. Bellamya snails were examined for cercariae with shedding or crushing methods, and identified by systematic k...

  3. Determination of wing cell fate by the escargot and snail genes in Drosophila.

    Science.gov (United States)

    Fuse, N; Hirose, S; Hayashi, S

    1996-04-01

    Inset appendages such as the wing and the leg are formed in response to inductive signals in the embryonic field. In Drosophila, cells receiving such signals initiate developmental programs which allow them to become imaginal discs. Subsequently, these discs autonomously organize patterns specific for each appendage. We here report that two related transcription factors, Escargot and Snail that are expressed in the embryonic wing disc, function as intrinsic determinants of the wing cell fate. In escargot or snail mutant embryos, wing-specific expression of Snail, Vestigial and beta-galactosidase regulated by escargot enhancer were found as well as in wild-type embryos. However, in escargot snail double mutant embryos, wing development proceeded until stage 13, but the marker expression was not maintained in later stages, and the invagination of the primordium was absent. From such analyses, it was concluded that Escargot and Snail expression in the wing disc are maintained by their auto- and crossactivation. Ubiquitous escargot or snail expression induced from the hsp70 promoter rescued the escargot snail double mutant phenotype with the effects confined to the prospective wing cells. Similar DNA binding specificities of Escargot and Snail suggest that they control the same set of genes required for wing development. We thus propose the following scenario for early wing disc development. Prospective wing cells respond to the induction by turning on escargot and snail transcription, and become competent for regulation by Escargot and Snail. Such cells initiate auto- and crossregulatory circuits of escargot and snail. The sustained Escargot and Snail expression then activates vestigial and other target genes that are essential for wing development. This maintains the commitment to the wing cell fate and induces wing-specific cell shape change. PMID:8620833

  4. Removal of corallivorous snails as a proactive tool for the conservation of acroporid corals

    Directory of Open Access Journals (Sweden)

    Dana E. Williams

    2014-11-01

    Full Text Available Corallivorous snail feeding is a common source of tissue loss for the threatened coral, Acropora palmata, accounting for roughly one-quarter of tissue loss in monitored study plots over seven years. In contrast with larger threats such as bleaching, disease, or storms, corallivory by Coralliophila abbreviata is one of the few direct sources of partial mortality that may be locally managed. We conducted a field experiment to explore the effectiveness and feasibility of snail removal. Long-term monitoring plots on six reefs in the upper Florida Keys were assigned to one of three removal treatments: (1 removal from A. palmata only, (2 removal from all host coral species, or (3 no-removal controls. During the initial removal in June 2011, 436 snails were removed from twelve 150 m2 plots. Snails were removed three additional times during a seven month “removal phase”, then counted at five surveys over the next 19 months to track recolonization. At the conclusion, snails were collected, measured and sexed. Before-After-Control-Impact analysis revealed that both snail abundance and feeding scar prevalence were reduced in removal treatments compared to the control, but there was no difference between removal treatments. Recolonization by snails to baseline abundance is estimated to be 3.7 years and did not differ between removal treatments. Recolonization rate was significantly correlated with baseline snail abundance. Maximum snail size decreased from 47.0 mm to 34.6 mm in the removal treatments. The effort required to remove snails from A. palmata was 30 diver minutes per 150 m2 plot, compared with 51 min to remove snails from all host corals. Since there was no additional benefit observed with removing snails from all host species, removals can be more efficiently focused on only A. palmata colonies and in areas where C. abbreviata abundance is high, to effectively conserve A. palmata in targeted areas.

  5. Snail sperm production characteristics vary with sperm competition risk

    OpenAIRE

    Oppliger, A.; Hosken, D J; Ribi, G

    1998-01-01

    Sperm competition is widespread and influences both male investment in spermatogenic tissue and ejaculate characteristics. Sperm competition models assume trade-offs between sperm size and number, although such trade-offs may be difficult to detect. This study examines the effects of sperm competition risk on the sperm production characteristics of the freshwater snail Viviparus ater. In this prosobranch, females mate frequently and store sperm, generating sperm competition. Males produce two...

  6. NCBI nr-aa BLAST: CBRC-DNOV-01-1557 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DNOV-01-1557 ref|NP_976175.1| NADH dehydrogenase subunit 2 [Biomphalaria glabr...ata] gb|AAQ75772.1| NADH dehydrogenase subunit 2 [Biomphalaria glabrata] NP_976175.1 0.70 24% ...

  7. NCBI nr-aa BLAST: CBRC-MDOM-01-0447 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MDOM-01-0447 ref|NP_976175.1| NADH dehydrogenase subunit 2 [Biomphalaria glabr...ata] gb|AAQ75772.1| NADH dehydrogenase subunit 2 [Biomphalaria glabrata] NP_976175.1 0.035 29% ...

  8. Trace metallic elements in Helix aspersa terrestrial snails of a semiarid ecosystem

    International Nuclear Information System (INIS)

    The concentration of some major elements and traces in soil samples and of Helix aspersa eatable terrestrial snails were analysed at the Radioactive Wastes Storage Center (CADER) and in other reference sites. The methodology includes the use of an atomic absorption spectrophotometer, an X-ray fluorescence equipment and an Icp-mass spectroscope. The concentrations of some toxic elements (Ba, Cd, Cr, Ni, Pb and V) in the soft tissue of the snails were greater than the toxic levels reported in the literature for such trace elements. The snails compared with another wild eatable foods present transfer coefficients soil-snail high relatively. (Author)

  9. Fascioliasis Control: In Vivo and In Vitro Phytotherapy of Vector Snail to Kill Fasciola Larva

    OpenAIRE

    Singh, D.K.; Kumari Sunita

    2011-01-01

    Snail is one of the important components of an aquatic ecosystem, it acts as intermediate host of Fasciola species. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. Life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria in the snail body. In vivo and in vitro toxicity of the plant products and their active component such as citral, ferulic acid, ...

  10. Impact of cigarette butt leachate on tidepool snails.

    Science.gov (United States)

    Booth, David J; Gribben, Paul; Parkinson, Kerryn

    2015-06-15

    In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2h soak time) after 8days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species. While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently. PMID:25913792

  11. Molluscicidal activity of Physalis angulata L. extracts and fractions on Biomphalaria tenagophila (d'Orbigny, 1835 under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Santos José Augusto A dos

    2003-01-01

    Full Text Available The main objective of this research is to evaluate the molluscicide activity of Physalis angulata L. Biomphalaria tenagophila specimens under laboratory conditions. Extracts and fractions were supplied by the Laboratório de Química de Produtos Naturais, Farmanguinhos-Fiocruz. Experiments were performed according to the methodology described by the World Health Organization for molluscicide tests using the concentrations from 0.1 to 500 mg/l of the extracts, fractions and of a pool of physalins modified steroids present in this species. The results show that ethyl acetate and acetone extracts from the whole plant, the ethanolic extracts of the roots and the physalins pool from stems and leaves were active. Only the whole plant extracts were available in sufficient quantity for the determination of LD50 and LD90 values.

  12. Dominant character of the molecular marker of a Biomphalaria tenagophila strain (Mollusca: Planorbidae resistant to Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Rosa Florence Mara

    2004-01-01

    Full Text Available Biomphalaria tenagophila population from Taim (state of Rio Grande do Sul, Brazil is totally resistant toSchistosoma mansoni, and presents a molecular marker of 350 bp by polymerase chain reaction and restriction fragment length polymorphism of the entire rDNA internal transcriber spacer. The scope of this work was to determine the heritage pattern of this marker. A series of cross-breedings between B. tenagophila from Taim (resistant and B. tenagophila from Joinville, state of Santa Catarina (susceptible was carried out, and their descendants F1 and F2 were submitted to this technique. It was possible to demonstrate that the specific fragment from Taim is endowed with dominant character, since the obtained segregation was typically mendelian.

  13. Susceptibility of non-target invertebrates to Brazilian microbial pest control agents.

    Science.gov (United States)

    Oliveira-Filho, Eduardo Cyrino; Muniz, Daphne Heloisa Freitas; Freire, Ingrid Souza; Ramos, Felipe Rosa; Alves, Roberto Teixeira; Jonsson, Claudio Martin; Grisolia, Cesar Koppe; Monnerat, Rose Gomes

    2011-08-01

    Microbial pest control agents or entomopathogens have been considered an interesting alternative to use instead of chemical insecticides. Knowledge of ecotoxicity data is very important to predict the hazard of any product released in the environment and subsidize the regulation of these products by governmental agencies. In the present study four new Brazilian strains of Bacillus and one fungus were tested to evaluate their acute toxicity to the microcrustacean Daphnia similis, the snail Biomphalaria glabrata and the dung beetle Digitonthophagus gazella. The microcrustaceans and the snails were exposed to entomopathogens in synthetic softwater and the beetles were exposed directly in cattle dung. Obtained data reveal low susceptibility of the non-target species to tested microorganisms, with lethal concentrations being observed only at much higher concentrations than that effective against target insects. These results show that the tested strains are selective in their action mode and seem to be non-hazardous to non-target species. PMID:21533653

  14. Biomphalaria straminea (Mollusca: Planorbidae) as an intermediate host of Drepanocephalus spp. (Trematoda: Echinostomatidae) in Brazil: a morphological and molecular study.

    Science.gov (United States)

    Pinto, Hudson A; Griffin, Matt J; Quiniou, Sylvie M; Ware, Cynthia; Melo, Alan L

    2016-01-01

    Species of trematodes belonging to the genus Drepanocephalus are intestinal parasites of piscivorous birds, primarily cormorants (Phalachrocorax spp.), and are widely reported in the Americas. During a 4-year malacological study conducted on an urban lake in Brazil, 27-collar-spined echinostome cercariae were found in 1665/15,459 (10.7 %) specimens of Biomphalaria straminea collected. The cercariae were identified as Drepanocephalus spp. by sequencing the 18S (SSU) rDNA, ITS1/5.8S rDNA/ITS2 (ITS), 28S (LSU) rDNA region, cytochrome oxidase subunit 1 (CO1), and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) markers. In experimental life cycle studies, metacercariae developed in laboratory-reared guppies (Poecilia reticulata); however, attempts to infect birds and rodents were unsuccessful. Two closely related morphotypes of cercariae were characterized. One species, identified by molecular markers as a genetic variant of Drepanocephalus auritus (99.9 % similarity at SSU, ITS, LSU; 97.2 % at CO1; 95.8 % at ND1), differs slightly from an archived North American isolate of this species also sequenced as part of this study. A second species, putatively identified as Drepanocephalus sp., has smaller cercariae and demonstrates significant differences from D. auritus at the CO1 (11.0 %) and ND1 (13.6 %) markers. Aspects related to the morphological taxonomic identification of 27-collar-spined echinostome metacercariae are briefly discussed. This is the first report of the involvement of molluscs of the genus Biomphalaria in the transmission of Drepanocephalus and the first report of D. auritus in South America. PMID:25982569

  15. Overexpression of Aldo-Keto-Reductase in Azole-resistant Clinical Isolates of Candida Glabrata Determined by cDNA-AFLP

    Directory of Open Access Journals (Sweden)

    Mansour Heidari

    2013-01-01

    Full Text Available Background: Candida glabrata causes significant medical problems in immunocompromised patients. Many strains of this yeast are intrinsically resistant to azole antifungal agents, and treatment is problematic, leading to high morbidity and mortality rates in immunosuppressed individuals. The primary goal of this study was to investigate the genes involved in the drug resistance of clinical isolates of C. glabrata.Methods: The clinical isolates of C. glabrata were collected in an epidemiological survey of candidal infection inimmunocompromised patients and consisted of four fluconazole and itraconazole resistant isolates, two fluconazoleand itraconazole sensitive isolates, and C. glabrata CBS 138 as reference strain. Antifungal susceptibility patterns ofthe organisms were determined beforehand by the Clinical and Laboratory Standards Institute (CLSI. The potentialgene(s implicated in antifungal resistance were investigated using complementary DNA- Amplified Fragment Length Polymorphism (cDNA-AFLP. Semi-quantitative RT-PCR was carried out to evaluate the expression of gene(s in resistant isolates as compared to sensitive and reference strains.Results and conclusions: The aldo-keto-reductase superfamily (AKR gene was upregulated in the resistant clinicalisolates as assessed by cDNA-AFLP. Semi-quantitative RT-PCR revealed AKR mRNA expression approximately twice that seen in the sensitive isolates. Overexpression of the AKR gene was associated with increased fluconazole and itraconazole resistance in C. glabrata. The data suggest that upregulation of the AKR gene might give a new insight into the mechanism of azole resistance.

  16. Overexpression of aldo-keto-reductase in azole-resistant clinical isolates of Candida glabrata determined by cDNA-AFLP

    Directory of Open Access Journals (Sweden)

    Farahyar Shirin

    2013-01-01

    Full Text Available Abstract Background Candida glabrata causes significant medical problems in immunocompromised patients. Many strains of this yeast are intrinsically resistant to azole antifungal agents, and treatment is problematic, leading to high morbidity and mortality rates in immunosuppressed individuals. The primary goal of this study was to investigate the genes involved in the drug resistance of clinical isolates of C. glabrata. Methods The clinical isolates of C. glabrata were collected in an epidemiological survey of candidal infection in immunocompromised patients and consisted of four fluconazole and itraconazole resistant isolates, two fluconazole and itraconazole sensitive isolates, and C. glabrata CBS 138 as reference strain. Antifungal susceptibility patterns of the organisms were determined beforehand by the Clinical and Laboratory Standards Institute (CLSI. The potential gene(s implicated in antifungal resistance were investigated using complementary DNA- Amplified Fragment Length Polymorphism (cDNA-AFLP. Semi-quantitative RT-PCR was carried out to evaluate the expression of gene(s in resistant isolates as compared to sensitive and reference strains. Results and conclusions The aldo-keto-reductase superfamily (AKR gene was upregulated in the resistant clinical isolates as assessed by cDNA-AFLP. Semi-quantitative RT-PCR revealed AKR mRNA expression approximately twice that seen in the sensitive isolates. Overexpression of the AKR gene was associated with increased fluconazole and itraconazole resistance in C. glabrata. The data suggest that upregulation of the AKR gene might give a new insight into the mechanism of azole resistance.

  17. Aquatic snails from mining sites have evolved to detect and avoid heavy metals.

    Science.gov (United States)

    Lefcort, H; Abbott, D P; Cleary, D A; Howell, E; Keller, N C; Smith, M M

    2004-05-01

    Toxicants in polluted environments are often patchily distributed. Hence, rather than being passive absorbers of pollution, some organisms have evolved the ability to detect and avoid toxicants. We studied the avoidance behavior of Physella columbiana, an aquatic pulmonate snail, in a pond that has been polluted with heavy metals for more than 120 years. Populations of this snail are rare at reference sites and are only robust at heavy-metal-polluted sites. We hypothesized that the snails are able to persist because they have evolved the ability to minimize their exposure to metals by actively avoiding metals in their environment. Using a Y-maze flow tank, we tested the avoidance behavior of snails to heavy-metal-polluted sediments and single-metal solutions of cadmium, zinc, or lead. We also tested the avoidance behaviors of the snails' laboratory-reared offspring raised in nonpolluted conditions. In addition, we tested the avoidance behavior of a small population of snails from a reference pond. Although all the snails we tested were able to detect low concentrations of heavy metals, we found that snails from the polluted site were the most sensitive, that their offspring were somewhat less sensitive, and that snails from the reference site were the least sensitive. This suggests that the ability of polluted-site snails to avoid heavy metals is both genetic and environmental. The concentrations of metals avoided by the snails from the polluted site were below the levels found at hot spots within their natal pond. The snails may be able to persist at this site because they decrease their exposure by moving to less-polluted sections of the pond. One application of our findings is the use of aquatic snails and our Y-maze design as an inexpensive pollution detector. Environmental pollutants such as lead, zinc, and arsenic are a problem throughout the world. People in underdeveloped countries often lack sophisticated pollution detection devices. We have developed a

  18. Snail transcription factor negatively regulates maspin tumor suppressor in human prostate cancer cells

    International Nuclear Information System (INIS)

    Maspin, a putative tumor suppressor that is down-regulated in breast and prostate cancer, has been associated with decreased cell motility. Snail transcription factor is a zinc finger protein that is increased in breast cancer and is associated with increased tumor motility and invasion by induction of epithelial-mesenchymal transition (EMT). We investigated the molecular mechanisms by which Snail increases tumor motility and invasion utilizing prostate cancer cells. Expression levels were analyzed by RT-PCR and western blot analyses. Cell motility and invasion assays were performed, while Snail regulation and binding to maspin promoter was analyzed by luciferase reporter and chromatin immunoprecipitation (ChIP) assays. Snail protein expression was higher in different prostate cancer cells lines as compared to normal prostate epithelial cells, which correlated inversely with maspin expression. Snail overexpression in 22Rv1 prostate cancer cells inhibited maspin expression and led to increased migration and invasion. Knockdown of Snail in DU145 and C4-2 cancer cells resulted in up-regulation of maspin expression, concomitant with decreased migration. Transfection of Snail into 22Rv1 or LNCaP cells inhibited maspin promoter activity, while stable knockdown of Snail in C4-2 cells increased promoter activity. ChIP analysis showed that Snail is recruited to the maspin promoter in 22Rv1 cells. Overall, this is the first report showing that Snail can negatively regulate maspin expression by directly repressing maspin promoter activity, leading to increased cell migration and invasion. Therefore, therapeutic targeting of Snail may be useful to re-induce expression of maspin tumor suppressor and prevent prostate cancer tumor progression

  19. New insights into parental effects and toxicity: Mate availability and diet in the parental environment affect offspring responses to contaminants

    International Nuclear Information System (INIS)

    Parental effects manifest as alterations in offspring phenotype resulting from the parental phenotype and/or parental environment. We evaluated the effects of parental diet quality and mating strategy on the toxicant tolerance of offspring in Biomphalaria glabrata snails. We raised snails either individually (self-fertilizing) or in groups of three (outcrossing) on a diet of uncooked lettuce, fish food, cooked lettuce, or cooked lettuce plus fish food. We then exposed their offspring to cadmium and malathion challenges. Cadmium tolerance varied with parental diet and was greater in the offspring of outcrossing snails than self-fertilizing snails. Malathion tolerance was not affected by parental diet but was greater in the offspring of outcrossing snails. These results indicate that offspring responses to stressors are heavily influenced by parental experience, but may depend on the specific stressor and the mechanism of action and/or detoxification. -- Highlights: •We reared parental snails either alone or in groups and fed them one of four diets. •We exposed their juvenile offspring to cadmium and malathion survival challenges. •Outcrossing increased toxicant tolerance of juveniles compared to self-fertilizing. •Parental diet affected juvenile offspring tolerance to cadmium but not malathion. •Toxicant characteristics likely influenced parental effects on toxicant tolerance. -- Both parental diet composition and mating strategy can significantly alter the toxicant tolerance of offspring, and toxicant characteristics likely influence the probability of parental effects

  20. Quantitative genetic analysis of subspecific differences in body shape in the snail-feeding carabid beetle Damaster blaptoides

    OpenAIRE

    Konuma, J; Sota, T; Chiba, S.

    2012-01-01

    A dimorphic pattern of macrocephalic (wide, short) and stenocephalic (narrow, long) body shapes is observed in snail-feeding carabid beetles globally. The former exhibits high performance in crushing snail shells with powerful jaws, whereas the latter specializes in eating snails' soft body directly by inserting the head into the shell. In the snail-feeding species Damaster blaptoides, the subspecies D. b. capito has a wide, short forebody, and D. b. fortunei has a narrow, long forebody. They...

  1. Trematodes obtained from the thiarid freshwater snail Melanoides tuberculata (Müller, 1774) as vector of human infections in Thailand

    OpenAIRE

    Duangduen Krailas; Suluck Namchote; Tunyarut Koonchornboon; Wivitchuta Dechruksa; Dusit Boonmekam

    2014-01-01

    Larval stages of trematodes obtained from the freshwater snail Melanoides tuberculata (Cerithioidea, Thiaridae) as intermediate host were studied by using cercarial emergence and crushing snails. Between December 2004 and September 2009 snails from one hundred twenty locations in Thailand were collected every two months for one year at each sampling site. Counts per unit of time method was used in this study, and the samples of snails were collected every 10 minutes per sampling by five colle...

  2. Studies on the Edible Terrestrial Snails Helix aspersa Muller Food Conversion Ratio in a Confined Microclimate System

    OpenAIRE

    Adrian Toader-Williams; Aurel Şara

    2010-01-01

    Terrestrial edible snail breeding is an agricultural activity that finds itself at pioneering stage in Romania. One of the species used in snail farming is Helix aspersa Muller. In order to accelerate their growth, farmers feed the snails with pumpkins as well as concentrated forage consisting of mix of flours to which calcium carbonate is added in order to supplement snails need for shell’s development. In a controlled microclimate environment we measured the average growth of six weeks old ...

  3. The effect of isolation on reproduction and growth of Pseudosuccinea columella (Pulmonata: Lymnaeidae: a snail-conditioned water experiment

    Directory of Open Access Journals (Sweden)

    Gutiérrez Alfredo

    2002-01-01

    Full Text Available A snail-conditioned water experiment was conducted in Pseudosuccinea columella to test the possible role of a chemical interaction between snails on the diminished growth and fecundity rates found for snails raised in pairs compared to those raised in complete isolation. The results permit to discard the hypothesis of an inhibition of growth and reproduction between snails due to factors released into the water.

  4. Activation of the ATM-Snail pathway promotes breast cancer metastasis

    Science.gov (United States)

    Sun, Mianen; Guo, Xiaojing; Qian, Xiaolong; Wang, Haibo; Yang, Chunying; Brinkman, Kathryn L.; Serrano-Gonzalez, Monica; Jope, Richard S.; Zhou, Binhua; Engler, David A.; Zhan, Ming; Wong, Stephen T.C.; Fu, Li; Xu, Bo

    2012-01-01

    The DNA damage response (DDR) is critical for the maintenance of genetic stability and serves as an anti-cancer barrier during early tumorigenesis. However, the role of the DDR in tumor progression and metastasis is less known. Here, we demonstrate that the ATM kinase, one of the critical DDR elements, is hyperactive in late stage breast tumor tissues with lymph-node metastasis and this hyperactivity correlates with elevated expression of the epithelial–mesenchymal transition marker, Snail. At the molecular level, we demonstrate that ATM regulates Snail stabilization by phosphorylation on Serine-100. Using mass spectrometry, we identified HSP90 as a critical binding protein of Snail in response to DNA damage. HSP90 binds to and stabilizes phosphorylated Snail. We further provide in vitro and in vivo evidence that activation of ATM-mediated Snail phosphorylation promotes tumor invasion and metastasis. Finally, we demonstrate that Snail Serine-100 phosphorylation is elevated in breast cancer tissues with lymph-node metastasis, indicating clinical significance of the ATM-Snail pathway. Together, our findings provide strong evidence that the ATM-Snail pathway promotes tumor metastasis, highlighting a previously undescribed role of the DDR in tumor invasion and metastasis. PMID:22923499

  5. Activation of the ATM-Snail pathway promotes breast cancer metastasis

    Institute of Scientific and Technical Information of China (English)

    Mianen Sun; David A. Engler; Ming Zhan; Stephen T.C. Wong; Li Fu; Bo Xu; Xiaojing Guo; Xiaolong Qian; Haibo Wang; Chunying Yang; Kathryn L. Brinkman; Monica Serrano-Gonzalez; Richard S. Jope; Binhua Zhou

    2012-01-01

    The DNA damage response (DDR) is critical for the maintenance of genetic stability and serves as an anti-cancer barrier during early tumorigenesis.However,the role of the DDR in tumor progression and metastasis is less known.Here,we demonstrate that the ATM kinase,one of the critical DDR elements,is hyperactive in late stage breast tumor tissues with lymph-node metastasis and this hyperactivity correlates with elevated expression of the epitheliai-mesenchymal transition marker,Snail.At the molecular level,we demonstrate that ATM regulates Snail stabilization by phosphorylation on Serine-100.Using mass spectrometry,we identified HSP90 as a critical binding protein of Snail in response to DNA damage.HsP9o binds to and stabilizes phosphorylated Snail.We further provide in vitro and in vivo evidence that activation of ATM-mediated Snail phosphorylation promotes tumor invasion and metastasis.Finally,we demonstrate that Snail Serine-100 phosphorylation is elevated in breast cancer tissues with lymph-node metastasis,indicating clinical significance of the ATM-Snail pathway.Together,our findings provide strong evidence that the ATM-Snail pathway promotes tumor metastasis,highlighting a previously undescribed role of the DDR in tumor invasion and metastasis.

  6. Local adaptation of the trematode Fasciola hepatica to the snail Galba truncatula

    Directory of Open Access Journals (Sweden)

    Dreyfuss G.

    2012-08-01

    Full Text Available Experimental infections of six riverbank populations of Galba truncatula with Fasciola hepatica were carried out to determine if the poor susceptibility of these populations to this digenean might be due to the scarcity or the absence of natural encounters between these snails and the parasite. The first three populations originated from banks frequented by cattle in the past (riverbank group whereas the three others were living on islet banks without any known contact with local ruminants (islet group. After their exposure, all snails were placed in their natural habitats from the end of October up to their collection at the beginning of April. Compared to the riverbank group, snails, which died without cercarial shedding clearly predominated in the islet group, while the other infected snails were few in number. Most of these last snails released their cercariae during a single shedding wave. In islet snails dissected after their death, the redial and cercarial burdens were significantly lower than those noted in riverbank G. truncatula. Snails living on these islet banks are thus able to sustain larval development of F. hepatica. The modifications noted in the characteristics of snail infection suggest the existence of an incomplete adaptation between these G. truncatula and the parasite, probably due to the absence of natural contact between host and parasite.

  7. Polycomb complex 2 is required for E-cadherin repression by the Snail1 transcription factor

    DEFF Research Database (Denmark)

    Herranz, Nicolás; Pasini, Diego; Díaz, Víctor M; Francí, Clara; Gutierrez, Arantxa; Dave, Natàlia; Escrivà, Maria; Hernandez-Muñoz, Inma; Di Croce, Luciano; Helin, Kristian; García de Herreros, Antonio; Peiró, Sandra

    2008-01-01

    -regulate CDH1 and partially de-represses CDH1. Chromatin immunoprecipitation assays demonstrated that Snail1 increases the binding of Suz12 to CDH1 promoter and the tri-methylation of lysine 27 in the histone 3. Moreover, Snail1 interacts with Suz12 and Ezh2 as shown by coimmunoprecipitation experiments. In...

  8. The fate of linear DNA in Saccharomyces cerevisiae and Candida glabrata: the role of homologous and non-homologous end joining.

    Directory of Open Access Journals (Sweden)

    Mary W Corrigan

    Full Text Available In vivo assembly of plasmids has become an increasingly used process, as high throughput studies in molecular biology seek to examine gene function. In this study, we investigated the plasmid construction technique called gap repair cloning (GRC in two closely related species of yeast - Saccharomyces cerevisiae and Candida glabrata. GRC utilizes homologous recombination (HR activity to join a linear vector and a linear piece of DNA that contains base pair homology. We demonstrate that a minimum of 20 bp of homology on each side of the linear DNA is required for GRC to occur with at least 10% efficiency. Between the two species, we determine that S. cerevisiae is slightly more efficient at performing GRC. GRC is less efficient in rad52 deletion mutants, which are defective in HR in both species. In dnl4 deletion mutants, which perform less non-homologous end joining (NHEJ, the frequency of GRC increases in C. glabrata, whereas GRC frequency only minimally increases in S. cerevisiae, suggesting that NHEJ is more prevalent in C. glabrata. Our studies allow for a model of the fate of linear DNA when transformed into yeast cells. This model is not the same for both species. Most significantly, during GRC, C. glabrata performs NHEJ activity at a detectable rate (>5%, while S. cerevisiae does not. Our model suggests that S. cerevisiae is more efficient at HR because NHEJ is less prevalent than in C. glabrata. This work demonstrates the determinants for GRC and that while C. glabrata has a lower efficiency of GRC, this species still provides a viable option for GRC.

  9. Snail/beta-catenin signaling protects breast cancer cells from hypoxia attack

    Energy Technology Data Exchange (ETDEWEB)

    Scherbakov, Alexander M., E-mail: alex.scherbakov@gmail.com [Laboratory of Clinical Biochemistry, Institute of Clinical Oncology, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation); Stefanova, Lidia B.; Sorokin, Danila V.; Semina, Svetlana E. [Laboratory of Molecular Endocrinology, Institute of Carcinogenesis, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation); Berstein, Lev M. [Laboratory of Oncoendocrinology, N.N. Petrov Research Institute of Oncology, St. Petersburg 197758 (Russian Federation); Krasil’nikov, Mikhail A. [Laboratory of Molecular Endocrinology, Institute of Carcinogenesis, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation)

    2013-12-10

    The tolerance of cancer cells to hypoxia depends on the combination of different factors – from increase of glycolysis (Warburg Effect) to activation of intracellular growth/apoptotic pathways. Less is known about the influence of epithelial–mesenchymal transition (EMT) and EMT-associated pathways on the cell sensitivity to hypoxia. The aim of this study was to explore the role of Snail signaling, one of the key EMT pathways, in the mediating of hypoxia response and regulation of cell sensitivity to hypoxia, using as a model in vitro cultured breast cancer cells. Earlier we have shown that estrogen-independent HBL-100 breast cancer cells differ from estrogen-dependent MCF-7 cells with increased expression of Snail1, and demonstrated Snail1 involvement into formation of hormone-resistant phenotype. Because Snail1 belongs to hypoxia-activated proteins, here we studied the influence of Snail1 signaling on the cell tolerance to hypoxia. We found that Snail1-enriched HBL-100 cells were less sensitive to hypoxia-induced growth suppression if compared with MCF-7 line (31% MCF-7 vs. 71% HBL-100 cell viability after 1% O{sub 2} atmosphere for 3 days). Snail1 knock-down enhanced the hypoxia-induced inhibition of cell proliferation giving the direct evidence of Snail1 involvement into cell protection from hypoxia attack. The protective effect of Snail1 was shown to be mediated, at least in a part, via beta-catenin which positively regulated expression of HIF-1-dependent genes. Finally, we found that cell tolerance to hypoxia was accompanied with the failure in the phosphorylation of AMPK – the key energy sensor, and demonstrated an inverse relationship between AMPK and Snail/beta-catenin signaling. Totally, our data show that Snail1 and beta-catenin, besides association with loss of hormone dependence, protect cancer cells from hypoxia and may serve as an important target in the treatment of breast cancer. Moreover, we suggest that the level of these proteins as well

  10. Snail/beta-catenin signaling protects breast cancer cells from hypoxia attack

    International Nuclear Information System (INIS)

    The tolerance of cancer cells to hypoxia depends on the combination of different factors – from increase of glycolysis (Warburg Effect) to activation of intracellular growth/apoptotic pathways. Less is known about the influence of epithelial–mesenchymal transition (EMT) and EMT-associated pathways on the cell sensitivity to hypoxia. The aim of this study was to explore the role of Snail signaling, one of the key EMT pathways, in the mediating of hypoxia response and regulation of cell sensitivity to hypoxia, using as a model in vitro cultured breast cancer cells. Earlier we have shown that estrogen-independent HBL-100 breast cancer cells differ from estrogen-dependent MCF-7 cells with increased expression of Snail1, and demonstrated Snail1 involvement into formation of hormone-resistant phenotype. Because Snail1 belongs to hypoxia-activated proteins, here we studied the influence of Snail1 signaling on the cell tolerance to hypoxia. We found that Snail1-enriched HBL-100 cells were less sensitive to hypoxia-induced growth suppression if compared with MCF-7 line (31% MCF-7 vs. 71% HBL-100 cell viability after 1% O2 atmosphere for 3 days). Snail1 knock-down enhanced the hypoxia-induced inhibition of cell proliferation giving the direct evidence of Snail1 involvement into cell protection from hypoxia attack. The protective effect of Snail1 was shown to be mediated, at least in a part, via beta-catenin which positively regulated expression of HIF-1-dependent genes. Finally, we found that cell tolerance to hypoxia was accompanied with the failure in the phosphorylation of AMPK – the key energy sensor, and demonstrated an inverse relationship between AMPK and Snail/beta-catenin signaling. Totally, our data show that Snail1 and beta-catenin, besides association with loss of hormone dependence, protect cancer cells from hypoxia and may serve as an important target in the treatment of breast cancer. Moreover, we suggest that the level of these proteins as well the

  11. Land snails (Mollusca: Gastropoda of India: status, threats and conservation strategies

    Directory of Open Access Journals (Sweden)

    S. Sen

    2012-09-01

    Full Text Available Land snails form an important component in the forest ecosystem. In terms of number of species, the phylum Mollusca, to which land snails belong, is the largest phylum after Arthropoda. Mollusca provide unique ecosystem services including recycling of nutrients and they provide a prey base for small mammals, birds, snakes and other reptiles. However, land snails have the largest number of documented extinctions, compared to any other taxa. Till date 1,129 species of land snails are recorded from Indian territory. But only basic information is known about their taxonomy and little is known of their population biology, ecology and their conservation status. In this paper, we briefly review status, threats and conservation strategies of land snails of India.

  12. Speciation and gene flow between snails of opposite chirality.

    Directory of Open Access Journals (Sweden)

    Angus Davison

    2005-09-01

    Full Text Available Left-right asymmetry in snails is intriguing because individuals of opposite chirality are either unable to mate or can only mate with difficulty, so could be reproductively isolated from each other. We have therefore investigated chiral evolution in the Japanese land snail genus Euhadra to understand whether changes in chirality have promoted speciation. In particular, we aimed to understand the effect of the maternal inheritance of chirality on reproductive isolation and gene flow. We found that the mitochondrial DNA phylogeny of Euhadra is consistent with a single, relatively ancient evolution of sinistral species and suggests either recent "single-gene speciation" or gene flow between chiral morphs that are unable to mate. To clarify the conditions under which new chiral morphs might evolve and whether single-gene speciation can occur, we developed a mathematical model that is relevant to any maternal-effect gene. The model shows that reproductive character displacement can promote the evolution of new chiral morphs, tending to counteract the positive frequency-dependent selection that would otherwise drive the more common chiral morph to fixation. This therefore suggests a general mechanism as to how chiral variation arises in snails. In populations that contain both chiral morphs, two different situations are then possible. In the first, gene flow is substantial between morphs even without interchiral mating, because of the maternal inheritance of chirality. In the second, reproductive isolation is possible but unstable, and will also lead to gene flow if intrachiral matings occasionally produce offspring with the opposite chirality. Together, the results imply that speciation by chiral reversal is only meaningful in the context of a complex biogeographical process, and so must usually involve other factors. In order to understand the roles of reproductive character displacement and gene flow in the chiral evolution of Euhadra, it will be

  13. Snails and slugs damaging the cut foliage, Cordyline fruticosa and use of biorationals towards their management.

    Science.gov (United States)

    Karthiga, S; Jegathambigai, V; Karunarathne, M D S D; Svinningen, A; Mikunthan, G

    2012-01-01

    Snails and slugs became a serious molluscan pests and damaging leaves of purple compacta, Cordyline fruticosa extensively grown for export at Green Farm Ltd, Sri Lanka. The export quality of leaves of C. fruticosa is lowered due to feeding of snails, Achantina fulica (Bowditch), Opeas pyrgula Schmacker and Boettgerx and Helix aspersa Muller and slugs incurring great loss to cut foliage industry. Paucity of information is available to understand snails and slugs damage and their host range that limits to develop suitable management practices. Therefore this study was aimed to determine damage, alternate hosts and to develop possible management practices. Snails and slugs damaged mainly fresh leaves of C. fruticosa. The severity of damage was 44.5% in infested field based on the visual rating method. Leaves of cassava, sting bean, okra, cucumber, passion fruit, papaya, Glyricidia and shoe flower were identified as alternate hosts and neem, Ixora and Dracaena spp were not served as alternate hosts. Among the plant materials tested for their repellence against snails and slugs revealed that neem seed powder was an irritant; neem leaves, mint leaves and Lantana leaves were acted as anti-feedant and Salt as chemical repellent. Among the barrier and bait experiments Bordeaux mixture exhibited a significant barrier effect against horizontal movement of snails. Baits made out of Metaldehyde bait, vegetables bait and jaggery had a strong effect in repelling the snails and slugs. Mulching with Madhuca longifolia punnac was the best to reduce the snails and slugs population compared to M. longifolia seed kernel powder. Oil from M. longifolia failed to reduce their population. Hence the results revealed that saponin containing M. longifolia punnac helped to eliminate snails and slugs when used as mulch. Metaldehyde, vegetable and jaggery baits are also useful to minimize their colonization further. Hence combination of these methods will help to prevent snails and slugs from

  14. The Epithelial-Mesenchymal Transition Factor SNAIL Paradoxically Enhances Reprogramming

    OpenAIRE

    Juli J. Unternaehrer; Rui Zhao; Kitai Kim; Marcella Cesana; John T. Powers; Sutheera Ratanasirintrawoot; Tamer Onder; Tsukasa Shibue; Robert A. Weinberg; George Q. Daley

    2014-01-01

    Stem Cell Reports Report The Epithelial-Mesenchymal Transition Factor SNAIL Paradoxically Enhances Reprogramming Juli J. Unternaehrer,1,2,3,7,* Rui Zhao,1,2,3,8 Kitai Kim,1,2,3,9 Marcella Cesana,1,2,3 John T. Powers,1,2,3 Sutheera Ratanasirintrawoot,1,2,3 Tamer Onder,1,2,3,10 Tsukasa Shibue,4,5 Robert A. Weinberg,4,5,6 and George Q. Daley1,2,3 1Division of Pediatric Hematology/Oncology, Stem Cell Transplantation Program, Manton Center for Orphan Disease Research, Howard H...

  15. An embryonic transcriptome of the pulmonate snail Radix balthica.

    Science.gov (United States)

    Tills, Oliver; Truebano, Manuela; Rundle, Simon

    2015-12-01

    The pond snail, Radix balthica (Linnaeus 1758), is an emerging model species within ecological developmental biology. While its development has been characterised in detail, genomic resources for embryonic stages are lacking. We applied Illumina MiSeq RNA-seq to RNA isolated from pools of embryos at two points during development. Embryos were cultured in either the presence or absence of predator kariomones to increase the diversity of the transcripts assembled. Sequencing produced 47.2M paired-end reads, assembled into 54,360 contigs of which 73% were successfully annotated. This transcriptome provides an invaluable resource to build a mechanistic understanding of developmental plasticity. PMID:26297600

  16. Biocatalytic reduction of racemic 2-arenoxycycloalkanones by yeasts P. glucozyma and C. glabrata: one way of achieving chiral 2-arenoxycycloalcohols.

    Science.gov (United States)

    Andreu, Cecilia; Peña, Miguel; Del Olmo, Marcel Lí

    2016-06-01

    Chiral β-aryloxy alcohols are interesting building blocks that form part of drugs like β adrenergic antagonists. Acquiring cyclic rigid analogs to obtain more selective drugs is interesting. Thus, we used whole cells of yeast strains Pichia glucozyma and Candida glabrata to catalyze the reduction of several 2-arenoxycycloalkanones to produce chiral 2-arenoxycycloalcohols with good/excellent enantioselectivity. In both cases, the alcohol configuration that resulted from the carbonyl group reduction was S. Yeast P. glucozyma allowed the conversion of both enantiomers of the starting material to produce 2-arenoxycycloalcohols with configuration (1S, 2R) and (1S, 2S). The reaction with C. glabrata nearly always allowed the kinetic resolution of the starting ketone, recovering 2-arenoxycycloalkanone with configuration S and (1S, 2R)-2-arenoxycycloalcohol.All the four possible stereoisomers of 2-phenoxycyclohexanol and the two enantiomers of 2-phenoxycyclohexanone were obtained by combining the biocatalyzed reaction with the oxidation/reduction of the chiral compounds with standard reagents. This is a simple approach for the synthesis of the rigid chiral moiety 2-arenoxycycloalcohols contained in putative β-blockers 2-arenoxycycloalkanepropanolamines. PMID:26754816

  17. Development of a Candida glabrata dominant nutritional transformation marker utilizing the Aspergillus nidulans acetamidase gene (amdS).

    Science.gov (United States)

    Fu, Jianmin; Blaylock, Morganne; Wickes, Cameron F; Welte, William; Mehrtash, Adrian; Wiederhold, Nathan; Wickes, Brian L

    2016-05-01

    The gene encodingAspergillus nidulansacetamidase (amdS) was placed under control ofCandida albicans ACT1promoter and terminator sequences and then cloned into a plasmid containingC. glabrata ARS10,CEN8orARS10+CEN8sequences. All plasmids transformedC. glabratawild-type cells to acetamide+, with theARS-only containing plasmid transforming cells at the highest frequencies (>1.0 × 10(4)transformants μg(-1)). Plasmids were rapidly lost under non-selective conditions with the frequency dependent on chromosomal element, thus recycling the acetamide- phenotype. TheamdSplasmid was used to transform a set of clinical isolates resistant to a variety of antifungal drugs. All strains were successfully transformed to the acetamide+ phenotype at high frequency, confirming that this plasmid construct could be used as a simple dominant marker on virtually any strain. Gap repair experiments demonstrated that just as inSaccharomyces cerevisiae, gap repair functions efficiently inC. glabrata, suggesting thatC. glabratahas numerous similarities toS. cerevisiaewith regard to ease of molecular manipulation. TheamdSsystem is inexpensive and efficient, and combined with existingC. glabrataplasmid elements, confers a high transformation frequency forC. glabratawith a phenotype that can be easily recycled. PMID:26975388

  18. THE USE OF Pomacea canaliculata SNAILS IN FEED TO IMPROVE QUALITY OF ALABIO DUCK (Anas plathyrinchos Borneo MEAT

    Directory of Open Access Journals (Sweden)

    A. Subhan

    2016-03-01

    Full Text Available This research was aimed to improve the physical and chemical quality of Alabio ducks which was fed with Pomacea canaliculata snails. Those ducks were raised intensively. There were nine treatments  included R0 (control feed, R1 (control feed + 2.5% Pomacea canaliculata snails from swampy area, R2 (control feed + 5% Pomacea canaliculata snails from swampy area, R3 (control feed + 7.5% Pomacea canaliculata snails from swampy area R4 (control feed + 10% Pomacea canaliculata snails from swampy area R5 (control feed + 2.5% Pomacea canaliculata snails from tidal swampy area, R6 (control feed + 5% Pomacea canaliculata snails from tidal swampy area, R7 (control feed + 7.5% Pomacea canaliculata snails from tidal swampy area, and R8 (control feed + 10% Pomacea canaliculata snails from tidal swampy area. The variables observed included meat chemical and physical quality. A Completely Randomized Design was used in this study. Analysis of variance and Duncan’s multiple range test were used to analyze data. The research results revealed that using Pomacea canaliculata snails in duck feed had a significant effect (P<0.05 towards the physical characteristics (water holding capacity, cooking loss, and tenderness, and chemical characteristics of Alabio duck meat (water, protein, collagen, fat, and cholesterol content. However, there was no significant effect towards meat pH. It can be concluded that using 5% Pomacea canaliculata snails in a mixture of Alabio duck feed decreased cooking loss and meat cholesterol content.

  19. The repressor function of snail is required for Drosophila gastrulation and is not replaceable by Escargot or Worniu.

    Science.gov (United States)

    Hemavathy, Kirugaval; Hu, Xiaodi; Ashraf, Shovon I; Small, Stephen J; Ip, Y Tony

    2004-05-15

    Mesoderm formation in the Drosophila embryo depends on the maternal Toll signaling pathway. The Toll pathway establishes the Dorsal nuclear gradient, which regulates many zygotic genes to establish the mesodermal fate and promote the invagination of ventral cells. An important target gene of Dorsal is snail, which is required for proper mesoderm invagination. The Snail protein contains five zinc fingers and is a transcriptional repressor. However, it is not clear whether repressing target genes is a requirement for Snail to control ventral invagination. To examine such requirement, we conducted a series of genetic rescue experiments in snail mutant embryos. Snail, Worniu, and Escargot are closely related zinc-finger proteins and have equal functions during neuroblast development. However, among these three proteins, only Snail can rescue the mesoderm invagination phenotype. Moreover, the ability of various Snail mutant constructs to repress gene expression correlates with their ability to control invagination. This unique property of Snail in mesoderm formation can be attributed mostly to the CtBP co-repressor interaction motifs in the N-terminus, not to the C-terminal DNA-binding zinc fingers. Ectopic expression of Snail outside the ventral domain is not sufficient to induce cell movement even though repression of target genes still occurs. Together, the results show that the repressor function of Snail is essential for gastrulation. The repression of target genes by Snail may permit other factors in the ventral cells to positively promote mesoderm invagination. PMID:15110709

  20. MYCOTOXINS CONTAMINATION IN EDIBLE LAND SNAIL AT GRAZING PADDOCK ENVIRONMENT

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    Ime Ebenso

    2013-02-01

    Full Text Available Mycotoxins contamination of animal products is under reported. Juvenile edible land snails (Archachatina marginata were exposed as sentinels in bottomless metal drums for 1 week at abandoned, new and reference sites respectively at grazing paddock environment, to assess the presence of foodborne microbiological mycotoxins contamination during the dry season. Mycological analysis of A. marginata samples revealed high (p<0.05 contamination at all paddocks ranged from 1.2-1.3 x 105 cfu-g. Results revealed values that were found to be unacceptable by FAO/WHO standards. The presence of Aspergillus niger, A. fumigatus and Penicillum expansum were noted as potential toxicogenic mycoflora. Snails were tolerant to all levels of contamination with no clinical signs of infection or mortality. This finding could serve as basis for assessing pre-slaughter microbial contamination of livestock farm/field environment in order to establish data with comparative epidemiological value, which could highlight early warning signals of food safety risk and cross-contamination of mycotoxins in the food chain.

  1. Characterizations of cholinesterases in golden apple snail (Pomacea canaliculata).

    Science.gov (United States)

    Zou, Xiang-Hui; Xie, Heidi Qun-Hui; Zha, Guang-Cai; Chen, Vicky Ping; Sun, Yan-Jie; Zheng, Yu-Zhong; Tsim, Karl Wah-Keung; Dong, Tina Ting-Xia; Choi, Roy Chi-Yan; Luk, Wilson Kin-Wai

    2014-07-01

    Cholinesterases (ChEs) have been identified in vertebrates and invertebrates. Inhibition of ChE activity in invertebrates, such as bivalve molluscs, has been used to evaluate the exposure of organophosphates, carbamate pesticides, and heavy metals in the marine system. The golden apple snail (Pomacea canaliculata) is considered as one of the worst invasive alien species harmful to rice and other crops. The ChE(s) in this animal, which has been found recently, but poorly characterized thus far, could serve as biomarker(s) for environmental surveillance as well as a potential target for the pest control. In this study, the tissue distribution, substrate preference, sensitivity to ChE inhibitors, and molecular species of ChEs in P. canaliculata were investigated. It was found that the activities of both AChE and BChE were present in all test tissues. The intestine had the most abundant ChE activities. Both enzymes had fair activities in the head, kidney, and gills. The BChE activity was more sensitive to tetra-isopropylpyrophosphoramide (iso-OMPA) than the AChE. Only one BChE molecular species, 5.8S, was found in the intestine and head, whereas two AChE species, 5.8S and 11.6S, were found there. We propose that intestine ChEs of this snail may be potential biomarkers for manipulating pollutions. PMID:24217797

  2. Snail regulates p21WAF/CIP1 expression in cooperation with E2 A and Twist

    International Nuclear Information System (INIS)

    Snail, a zinc-finger transcriptional repressor, is essential for mesoderm and neural crest cell formation and epithelial-mesenchymal transition. The basic helix-loop-helix transcription factors E2A and Twist have been linked with Snail during embryonic development. In this study, we examined the role of Snail in cellular differentiation through regulation of p21WAF/CIP1 expression. A reporter assay with the p21 promoter demonstrated that Snail inhibited expression of p21 induced by E2A. Co-expression of Snail with Twist showed additive inhibitory effects. Deletion mutants of the p21 promoter revealed that sequences between -270 and -264, which formed a complex with unidentified nuclear factor(s), were critical for E2A and Snail function. The E2A-dependent expression of the endogenous p21 gene was also inhibited by Snail

  3. [Dynamic transmission of Schistosoma by Biomphalaria pfeifferi in the region of Man in Côte d'Ivoire].

    Science.gov (United States)

    Yapi Yapi, G; Touré, M; Boka, O M; Tia, E; Boby, O A-M

    2014-12-01

    Intestinal schistosomiasis by Schistosoma mansoni is a parasitary affection transmitted in West Africa by the mollusc Biomphalaria pfeifferi. Transmission dynamic of schistosomiasis by Biomphalaria pfeifferi has seldom been investigated in Côte d'Ivoire. In the framework of a research project on the epidemiology of schistosomiasis in the natural forest ecosystems, this study was performed longitudinally over a period of three years in Man region, in western Côte d'Ivoire. The trial set up from 1986 to 1989 and the project was funded by the World Health Organization. The general objective is to design a strategy of schistosomiasis control based on chemotherapy. The approach aims at interrupting or considerably reducing the reinfections, prolonging in that way the duration of the positive effects of the chemotherapy. The specific objectives assigned to the work consisted in studying the dynamic of the B. pfeifferi population and the infection of B. pfeifferi. To achieve our objectives, diverse methods (i: the molluscs sampling by two prospectors during 15 minutes per study site and ii: individual isolation of molluscs in test tubes with 5 or 10 mL of filtered water and exposure to light) have been used. They enabled us in the sampling of the intermediary host molluscs of Schistosoma and seek their infections. The results show that apparent high densities of B. pfeifferi can be observed at the end of the dry season and at the beginning of rainy seasons. In addition, the variation of relative abundance of intermediary host molluscs of Schistosoma is significantly influenced by rainfall and the system of water ways. The period of transmission of the infection to man is six months at Gueupleu village and ten months at Botonguiné village. In order to optimize the effect of chemotherapy in these sites of transmission characterized by a high level of endemy (68 %), an extreme mobility of human populations and a multiplicity of contamination sites, this study should not

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

    Institute of Scientific and Technical Information of China (English)

    Thapana Chontananarth; Chalobol Wongsawad

    2013-01-01

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

  5. Comparative toxicity of Paraquat herbicide and some plant extracts in Lymnaea natalensis snails.

    Science.gov (United States)

    Bakry, Fayez A; Eleiwa, Mona E; Taha, Samir A; Ismil, Somya M

    2016-01-01

    Paraquat has been shown to be a highly toxic compound for humans and animals, and many cases of acute poisoning and death have been reported over the past few decades. The present study was undertaken to evaluate comprehensively herbicides (Paraquat) and some plant extracts to biochemical aspects of Lymnaea natalensis snails. It was found that the exposure of L. natalensis to Paraquat and plant extracts led to a significant reduction in the infectivity of Fasciola gigantica miracidia to the snail. The glucose level in hemolymph of exposed snails was elevated, while the glycogen showed a decrease in soft tissues when compared with the control group. In addition, the activity level of some enzymes representing glycolytic enzymes as hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK), lactate dehydrogenase (LDH), and glucose phosphate isomerase (GPI) in snail's tissues were reduced in response to the treatment. It was concluded that the pollution of the aquatic environment by herbicide would adversely affect the metabolism of the L. natalensis snails. Snails treated with Agave attenuate, Ammi visnaga, and Canna iridiflora plant had less toxic effect compared to snails treated with Paraquat. PMID:24081640

  6. Taken to the limit--Is desiccation stress causing precocious encystment of trematode parasites in snails?

    Science.gov (United States)

    O'Dwyer, Katie; Poulin, Robert

    2015-12-01

    When hosts experience environmental stress, the quantity and quality of resources they provide for parasites may be diminished, and host longevity may be decreased. Under stress, parasites may adopt alternative strategies to avoid fitness reductions. Trematode parasites typically have complex life cycles, involving asexual reproduction in a gastropod first intermediate host. A rare phenomenon, briefly mentioned in the literature, and termed 'precocious encystment' involves the next stage in the parasites' life cycle (metacercarial cyst) forming within the preceding stage (redia), while still inside the snail. In the trematode Parorchis sp. NZ using rocky shore snails exposed to long periods outside water, we hypothesised that this might be an adaptive strategy against desiccation, preventing parasite emergence from the snail. To test this, we first investigated the effect of prolonged desiccation on the survival of two species of high intertidal snails. Secondly, we measured the reproductive output (cercarial production) of the parasite under wet and dry conditions. Finally, we quantified the influence of desiccation stress on the occurrence of precocious encystment. Snail mortality was higher under dry conditions, indicating stress, and it was somewhat exacerbated for infected snails. Parasite reproductive output differed between wet and dry conditions, with parasites of snails kept in dry conditions producing more cercariae when placed in water. Little variation was observed in the occurrence of precocious encystment, although some subtle patterns emerged. Given the stresses associated with living in high intertidal environments, we discuss precocious encystment as a possible stress response in this trematode parasite. PMID:26344863

  7. Arsenic transfer and impacts on snails exposed to stabilized and untreated As-contaminated soils

    International Nuclear Information System (INIS)

    An As-contaminated soil (Unt) was amended with either iron grit (Z), a coal fly ash (beringite, B) or B + Z (BZ) and placed in lysimeters in 1997. An uncontaminated soil (R) was also studied. In summer and autumn 2003, lettuces were cultivated in the lysimeters and snails were caged for one month. Lettuce As concentrations were higher during the summer, while no differences occurred in snails between seasons. Snail As concentrations (μg g-1 DW) ranged from 2.5 to 7.0 in B, Z and BZ, and peaked at 17.5 in Unt. In summer, snail survival was affected in Unt and Z compared to R and B while no mortality was noticed in autumn. Snail growth decreased only in B, BZ and Unt in autumn. Snail As concentrations suggest a risk for their predators even on the remediated soils. - The addition of beringite along with iron grit into an As-contaminated soil decreases As transfer to and impacts on snails.

  8. [Life span and cercaria shedding of schistosome-infected snails in mountain region of Yunnan].

    Science.gov (United States)

    Xie, F; Yin, G; Wu, J; Duan, Y; Zhang, X; Yang, J; Qian, K; Tan, H; Zheng, J; Zhang, R

    1990-01-01

    The life span and cercaria shedding of infected Oncomelania snails in a mountain region of Shitoudi village, Weishan County, Yunnan Province were observed in simulated local ecological environments. 135 infected snails were isolated for observation 3 months after exposure to miracidia in August, 1987. The snail survival rate from the day of initial cercaria shedding to next June, July, August and September was 27.4, 16.3, 13.3 and 11.9% respectively, and the average number of cercariae shed was 139.9, 29.6, 39.2 and 75 per month respectively. The average life span of infected snails was 171.6 days. The average number of cercariae shed per snail in its whole life was 673.0. It was estimated that the average patent period of infected snails was over half a year. As this is the first report in our country in respect to the life span and cercariae shedding of infected snails in a mountain region, the result might be useful for quantitative analysis of epidemiological factors of schistosomiasis in this kind of endemic areas as well as for formulation of control strategy. PMID:2114229

  9. The mesoderm determinant snail collaborates with related zinc-finger proteins to control Drosophila neurogenesis.

    Science.gov (United States)

    Ashraf, S I; Hu, X; Roote, J; Ip, Y T

    1999-11-15

    The Snail protein functions as a transcriptional regulator to establish early mesodermal cell fate. Later, in germ band-extended embryos, Snail is also expressed in most neuroblasts. Here we present evidence that this expression of Snail is required for central nervous system (CNS) development. The neural function of snail is masked by two closely linked genes, escargot and worniu. Both Escargot and Worniu contain zinc-finger domains that are highly homologous to that of Snail. Although not affecting expression of early neuroblast markers, the deletion of the region containing all three genes correlates with loss of expression of CNS determinants including fushi tarazu, pdm-2 and even-skipped. Transgenic expression of each of the three Snail family proteins can rescue efficiently the fushi tarazu defects, and partially the pdm-2 and even-skipped CNS patterns. These results demonstrate that the Snail family proteins have essential functions during embryonic CNS development, around the time of ganglion mother cell formation. PMID:10562554

  10. Utilisation of Giant African snail (Achatina fulica meal as protein source for laying hens

    Directory of Open Access Journals (Sweden)

    Siaka Seriba Diarra

    2015-05-01

    Full Text Available A 12-week experiment was carried out to investigate the effects of substituting Giant African snail meal for fish meal in laying hens diet. Four diets were formulated to contain snail meal as replacement for fish meal at 0 (control, 33, 67 and 100 %. A total of 120 Shaver Brown pullets aged 18 weeks were allocated to the dietary treatments in a randomised design. Each treatment consisted of three replicates and ten birds per replicate. Feed intake increased only for the 33% treatment as compared to the 67% replacement diet but did not differ from the other treatments. There were no significant treatment effects on egg performance parameters observed (egg production, egg weight, total egg mass, feed conversion ratio and percent shell. The overall feed cost of egg production reduced on the snail mealbased diets. The organoleptic evaluation of boiled eggs revealed no difference between the treatments. Based on these results it was concluded that total replacement of fish meal with cooked snail meat meal does not compromise laying performance or egg quality. The substitution is beneficial in terms of production cost reduction and the reduction of snails will have a beneficial impact especially where these snails are a serious agricultural pest. The manual collection and processing of snails can also become a source of rural income.

  11. Interaction of gamma radiation on the functionality of the molluscicidal extract of Anacardium occidentale Linn

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gustavo Henrique Farias dos [Grupo de Estudos em Radioprotecao e Radioecologia (GERAR) . Departamento de Energia Nuclear. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Silva, Edvane Borges da [Centro Academico de Vitoria. Universidade Federal de Pernambuco (UFPE), Vitoria de Santo Antao, PE (Brazil); Amorim, Elba Lucia C.; Peixoto Sobrinho, Tadeu J.S., E-mail: elba@ufpe.br [Departamento de Ciencias Farmaceuticas. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Melo, Ana Maria Mendonca de Albuquerque; Lima, Claudia Sampaio de Andrade [Departamento de Biofisica e Radiobiologia. Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2011-07-01

    Biological control of Biomphalaria glabrata that is the intermediate host of Schistosoma mansoni, through molluscicides has been an alternative against schistosomiasis. Many studies have been developed to obtain molluscicide products, from plants. Anacardium occidentale L. (cashew), a plant rich in phenolic compounds shows molluscicidal activity in earlier assays. However there is an interest of enhancing the action of bioactive substances in order to use it in small concentrations, reducing costs in their utilization. This study were conducted using ethanolic extracts of bark and leaves of A. occidentale, before and after exposure to gamma radiation from {sup 60}Co, checking their secondary metabolites, their biological activity against Biomphalaria glabrata and environmental toxicity. The extracts of A. occidentale were obtained by cold maceration in 70% ethanol, filtered, dried and divided into two experimental groups: control (0 kGy) and irradiated at a dose of 10 kGy. The quantification of metabolites was performed in six replicates for the determination of total phenols by Folin-Ciocalteau method and tannins, the precipitation of casein. Tests for biological control of embryos and adults of B. glabrata snails and assessment of environmental toxicity (using Artemia salina larvae) were performed in triplicate, following a period of 24 hours of exposure to extracts at a concentration of 100 mg/L and its respective controls. Data were expressed as percentages of means and standard deviations. The results showed that the gamma radiation from {sup 60}Co resulted in leaf extracts, increased levels of total phenols and tannins, which enhanced the lethality for embryos and adults of B. glabrata. There was a reduction of the toxicity of leaf extracts after irradiation in the Artemia salina. Since in extracts of bark, gamma radiation did not alter the levels of total phenols and tannins, however, it was noted potentiation of lethality of adult snails of B. glabrata. The

  12. Interaction of gamma radiation on the functionality of the molluscicidal extract of Anacardium occidentale Linn

    International Nuclear Information System (INIS)

    Biological control of Biomphalaria glabrata that is the intermediate host of Schistosoma mansoni, through molluscicides has been an alternative against schistosomiasis. Many studies have been developed to obtain molluscicide products, from plants. Anacardium occidentale L. (cashew), a plant rich in phenolic compounds shows molluscicidal activity in earlier assays. However there is an interest of enhancing the action of bioactive substances in order to use it in small concentrations, reducing costs in their utilization. This study were conducted using ethanolic extracts of bark and leaves of A. occidentale, before and after exposure to gamma radiation from 60Co, checking their secondary metabolites, their biological activity against Biomphalaria glabrata and environmental toxicity. The extracts of A. occidentale were obtained by cold maceration in 70% ethanol, filtered, dried and divided into two experimental groups: control (0 kGy) and irradiated at a dose of 10 kGy. The quantification of metabolites was performed in six replicates for the determination of total phenols by Folin-Ciocalteau method and tannins, the precipitation of casein. Tests for biological control of embryos and adults of B. glabrata snails and assessment of environmental toxicity (using Artemia salina larvae) were performed in triplicate, following a period of 24 hours of exposure to extracts at a concentration of 100 mg/L and its respective controls. Data were expressed as percentages of means and standard deviations. The results showed that the gamma radiation from 60Co resulted in leaf extracts, increased levels of total phenols and tannins, which enhanced the lethality for embryos and adults of B. glabrata. There was a reduction of the toxicity of leaf extracts after irradiation in the Artemia salina. Since in extracts of bark, gamma radiation did not alter the levels of total phenols and tannins, however, it was noted potentiation of lethality of adult snails of B. glabrata. The analysis

  13. Occurrence of a Snail Borne Disease, Cercarial Dermatitis (Swimmer Itch in Doon Valley (Uttarakhand, India.

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Jauhari

    2014-02-01

    Full Text Available 'Cercarial dermatitis' also known as swimmers itch (Skin allergies is caused by a trematode parasite, Schistosoma which has two hosts - an invertebrate (snail and a vertebrate (livestock, human being. Although the availability of both vector snails and pathogens at the selected site the Doon Valley in northern India has already been confirmed but there was a hazy picture of the disease, whether it is due to entrance of cercariae or due to wild variety of grass (Parthenium hysterophorus. The present study is an attempt to provide a way forward towards the vector snails and snail borne diseases in the study area.Snail sampling and identification was done by applying standard methods / using Keys & Catalogues. Associated parasites and cercariometry in snails has been worked out by cercarial shedding. Human involvement at zo-onotic level has been performed in collaboration with Health centers and socio- economic aspect of inhabitants of study area.The snail diversity encountered 19 species including the vector species such as Indoplanorbis exustus, Gyraulus convexiusculus, Melanoides tuberculata and Lymnaea acuminata. The cercarial diversity comprised Furcocercous, Monostome, Amphistome and liver fluke / Xiphidiocercaria. During the study (2009-2010, 0.173% was found with cercarial dermatitis among human population in the selected area. The symptoms of disease recorded were red spots and swellings on effected parts of skin. Frequent visits of livestock to the water body and presence of vector snails provides a clue in completing the life cycle of the parasite of the family Schistosomatidae.Cercarial dermatitis has been considered a potential risk at those places where warm blooded and snail's hosts share a link with aquatic bodies with particular emphasis to temperature and time of year.

  14. The uptake and distribution of copper sulphate by the freshwater snail bulinus (bulinus) tropicus

    International Nuclear Information System (INIS)

    The copper concentration found in the haemolymph, shell and the whole snail was determined by atomic absorption spectrophotometry. These concentration values were designated as the background copper concentration. No copper was found in the snail haemolymph or the shell after a six hour exposure of snails to 1 ppm CuSO4. This exposure to CuSO4 was done at a pH of 7,2 and 8,4. Because of differences in the solubility of coppersulphate at different pH levels the amount of copper available in aquarium water at pH 4, 7,2 and 8,4 was determined by atomic absorption spectrophotometry. Snails which have accumulated copper do not release the copper into the water. For this experiment the water was analysed for copper for a period of 24 hours. This test was done using an atomic absorption spectrophotometer and radio-active copper (Cu64). Snails were also exposed to increasing concentrations of CuSO4 and at the same time the decrease of copper from the water was monitored. The relationship between copper uptake by the snail and its increasing metabolic rate showed that the rate of copper uptake does not increase with increasing metabolic activity. An experiment to measure the adsorption of copper by dead snail tissue was performed. Transmission electron microscopy showed histological changes in the subepithelial tissues. The results obtained from the various experiments indicate that copper is adsorbed on the exposed body wall of the snail. It is suggested that chemisorption and not physisorption could be the underlying mechanism of adsorption of copper on the snails outer epithelium

  15. Electron Spin Resonance Studies of Mn2+ in Freshwater Snail Shells: Pomacea Canaliculata Lamarck and Fossilized Snail Shell

    Institute of Scientific and Technical Information of China (English)

    N. Udomkan; S. Meejoo; P. Limsuwan; P. Winotai; Y. Chaimanee

    2005-01-01

    @@ We study paramagnetic Mn2+ ions present in the nowadays shells of univalve freshwater snails of Pomacea canaliculata lamarck (PCL) and the fossilized freshwater snail (FFS), Viviparus. All these shells are abundant in Thailand. The PCL shells were ground into fine powder. A set of seven samples were then separately annealed for 2 h in air atmosphere at different annealing temperatures while the FFS powder was characterized as-received.The PCL shells mainly consist of aragonite and a fraction of calcite. The heat treatments of the PCL powder samples at temperature higher than 450 ℃ resulted in an irreversible phase transformation from aragonite to calcite. However, it is found that the FFS shell is mainly made of calcite, with a minor fraction of aragonite. The crystal structure of the high-temperature-annealed PCL samples are quite similar to that of FFS, which indicates that the metamorphosis (aragonite → calcite) in the FFS shell had occurred but was not yet completed, although it had remained under the pressure and temperature of the Earth's crusts over millions of years. Our detailed ESR spectral analyses of PCL and FFS show that Mn2+ ions enter the Ca2+ sites during a biomineralization process. Simulated ESR parameters of PCL-500 of Mn2+ at a uniaxial site of calcite are reported. It is surprising to find that the ratio of Mn2+ concentration present in FFS to those in PCL shells evaluated from ESR spectra is as much as 10:1.

  16. Amino acid, fatty acid, vitamin and mineral contents of the edible garden snail (Helix aspersa)

    OpenAIRE

    Ferhat Çağıltay; (1), Nuray Erkan; Deniz Tosun; Arif Selçuk

    2011-01-01

    The nutritive and market value of meat of edible garden snail from northern Turkey was deter¬mined. Protein, fat, ash, water and carbohydrate value of edible garden snail were found 9.87, 0.58, 1.07, 82.50 and 5.99 % wet weight, respectively. The results of this study have showed that garden snails are good sources of amino acid, fatty acid, vitamins and minerals. The ly¬sine, isoleucine and leucine content from essential amino acids were 721, 467.57 and 611.50 mg/100g, respectively. The m...

  17. Modelling climate change impact on the spatial distribution of fresh water snails hosting trematodes in Zimbabwe

    OpenAIRE

    Pedersen, Ulrik Bo; Stendel, Martin; Midzi, Nicholas; Mduluza, Takafira; Soko, White; Stensgaard, Anna-Sofie; Vennervald, Birgitte J.; Mukaratirwa, Samson; Kristensen, Thomas K

    2014-01-01

    Background Freshwater snails are intermediate hosts for a number of trematodes of which some are of medical and veterinary importance. The trematodes rely on specific species of snails to complete their life cycle; hence the ecology of the snails is a key element in transmission of the parasites. More than 200 million people are infected with schistosomes of which 95% live in sub-Saharan Africa and many more are living in areas where transmission is on-going. Human infection with the Fasciola...

  18. The Use of Golden Snail (Pomacea sp.) as Animal Feed in the Philippines

    OpenAIRE

    Serra, AB

    1997-01-01

    The golden snail is introduced to the Philippines in early 80's for culture as food source. This herbivorous snail, a voracious feeder of live and fresh plant materials become a serious rice pest. Its elimination in the ecosystems is impossible. To use them as animal feed is much better alternative for their control and more environmentally friendly than the use of chemicals. Thus, this mini review paper aimed to collate any existing information on the use of golden snail as animal feed. The ...

  19. Spatial distribution of schistosomiasis foci on Itamaracá Island, Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    CS Barbosa

    2004-08-01

    Full Text Available Acute cases of schistosomiasis have been found on the coastal area of Pernambuco, Brazil, due to environmental disturbances and disorderly occupation of the urban areas. This study identifies and spatially marks the main foci of the snail host species, Biomphalaria glabrata on Itamaracá Island. The chaotic occupation of the beach resorts has favoured the emergence of transmission foci, thus exposing residents and tourists to the risk of infection. A database covering five years of epidemiological investigation on snails infected by Schistosoma mansoni in the island was produced with information from the geographic positioning of the foci, number of snails collected, number of snails tested positive, and their infection rate. The spatial position of the foci were recorded through the Global Positioning System (GPS, and the geographical coordinates were imported by AutoCad. The software packages ArcView and Spring were used for data processing and spatial analysis. AutoCad 2000 was used to plot the pairs of coordinates obtained from GPS. Between 1998 and 2002 5009 snails, of which 12.2% were positive for S. mansoni, were collected in Forte Beach. A total of 27 foci and areas of environmental risk were identified and spatially analyzed allowing the identification of the areas exposed to varying degrees of risk.

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

    Directory of Open Access Journals (Sweden)

    Balan Doralice de Souza Luro

    1993-01-01

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

  1. Evaluation of reference genes for real-time quantitative PCR studies in Candida glabrata following azole treatment

    Directory of Open Access Journals (Sweden)

    Li Qingdi

    2012-06-01

    Full Text Available Abstract Background The selection of stable and suitable reference genes for real-time quantitative PCR (RT-qPCR is a crucial prerequisite for reliable gene expression analysis under different experimental conditions. The present study aimed to identify reference genes as internal controls for gene expression studies by RT-qPCR in azole-stimulated Candida glabrata. Results The expression stability of 16 reference genes under fluconazole stress was evaluated using fold change and standard deviation computations with the hkgFinder tool. Our data revealed that the mRNA expression levels of three ribosomal RNAs (RDN5.8, RDN18, and RDN25 remained stable in response to fluconazole, while PGK1, UBC7, and UBC13 mRNAs showed only approximately 2.9-, 3.0-, and 2.5-fold induction by azole, respectively. By contrast, mRNA levels of the other 10 reference genes (ACT1, EF1α, GAPDH, PPIA, RPL2A, RPL10, RPL13A, SDHA, TUB1, and UBC4 were dramatically increased in C. glabrata following antifungal treatment, exhibiting changes ranging from 4.5- to 32.7-fold. We also assessed the expression stability of these reference genes using the 2-ΔΔCT method and three other software packages. The stability rankings of the reference genes by geNorm and the 2-ΔΔCT method were identical to those by hkgFinder, whereas the stability rankings by BestKeeper and NormFinder were notably different. We then validated the suitability of six candidate reference genes (ACT1, PGK1, RDN5.8, RDN18, UBC7, and UBC13 as internal controls for ten target genes in this system using the comparative CT method. Our validation experiments passed for all six reference genes analyzed except RDN18, where the amplification efficiency of RDN18 was different from that of the ten target genes. Finally, we demonstrated that the relative quantification of target gene expression varied according to the endogenous control used, highlighting the importance of the choice of internal controls in such

  2. SNAIL gene inhibited by hypoxia-inducible factor 1α (HIF-1α) in epithelial ovarian cancer.

    Science.gov (United States)

    Zhang, Pengnan; Liu, Yanmei; Feng, Youji; Gao, Shujun

    2016-09-01

    The aim of this study was to investigate the relationship between HIF-1α and SNAIL gene expression in the epithelial ovarian cancer (EOC) cell line. EOC cells were treated with hypoxia, hypoxia combined with rapamycin, and control. The expression of HIF-1α and E-cad were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. The gene expression of SNAIL was studied by RT-PCR and real-time PCR. RNA interference technology was used to determine the relationship between HIF-1α and SNAIL. The present study indicated that the HIF-1α protein was expressed and increased in EOC cell line. SNAIL mRNA was found to increase and E-cad expression decreased with the time of hypoxia prolonged. Hypoxia increased invasion abilities of EOC cell line, but compared with cells exposed to hypoxia, the change of invasive ability of cells with rapamycin had no effect. The expression of HIF-1α protein and SNAIL mRNA could be inhibited gradually by rapamycin. siRNA of HIF-1α could suppress the expression of SNAIL while siRNA of SNAIL had no influence on HIF-1α protein expression. HIF-1α may be the upstream of the SNAIL gene in EOC. Our data suggested that HIF-1α might be an upregulator of the SNAIL gene and HIF-1α-SNAIL-E-cad pathway may play an important role in EOC invasion and metastasis. PMID:27044634

  3. Microbiological and chemical analysis of land snails commercialised in Sicily

    Directory of Open Access Journals (Sweden)

    Antonello Cicero

    2015-05-01

    Full Text Available In this study 160 samples of snails belonging to the species Helix aspersa maxima and Helix aspersa muller were examined for chemical and microbiological analysis. Samples came from Greece and Poland. Results showed mean concentration of cadmium (0.35±0.036 mg/kg and lead (0.05±0.013 mg/kg much higher than the limit of detection. Mercury levels in both species were not detected. Microbiological analysis revealed the absence of Salmonella spp. and Clostridium spp. in both examined species. E. coli and K. oxytoca were observed in Helix aspersa maxima and Helix aspersa muller. Furthermore, one case of fungi positivity in samples of Helix aspersa muller was found. The reported investigations highlight the need to create and adopt a reference legislation to protect the health of consumers.

  4. Solar radio-transmitters on snail kites in Florida

    Science.gov (United States)

    Snyder, N.F.R.; Beissinger, S.R.; Fuller, M.R.

    1989-01-01

    The effectiveness and safety of one- and two-stage solar radio-transmitters in tracking the movements and survival of adult and fledgling Snail Kites (Rostrhamus sociabilis) were evaluated between 1979 and 1983 in southern Florida. Transmitters were attached to birds with back-pack arrangements using teflon ribbon straps. Accessory plastic shields minimized feather coverage of the solar cells. Intact transmitters were seen on birds up to 47 mo after installation. Operating lives ranged from 8 to 21 mo for one-stage, and 10 to 14 mo for two-stage transmitters. Because survival of adult and nestling radio-marked kites was high, we conclude that our transmitter-attachment method had little effect on the birds.

  5. The Epithelial-Mesenchymal Transition Factor SNAIL Paradoxically Enhances Reprogramming

    Directory of Open Access Journals (Sweden)

    Juli J. Unternaehrer

    2014-11-01

    Full Text Available Reprogramming of fibroblasts to induced pluripotent stem cells (iPSCs entails a mesenchymal to epithelial transition (MET. While attempting to dissect the mechanism of MET during reprogramming, we observed that knockdown (KD of the epithelial-to-mesenchymal transition (EMT factor SNAI1 (SNAIL paradoxically reduced, while overexpression enhanced, reprogramming efficiency in human cells and in mouse cells, depending on strain. We observed nuclear localization of SNAI1 at an early stage of fibroblast reprogramming and using mouse fibroblasts expressing a knockin SNAI1-YFP reporter found cells expressing SNAI1 reprogrammed at higher efficiency. We further demonstrated that SNAI1 binds the let-7 promoter, which may play a role in reduced expression of let-7 microRNAs, enforced expression of which, early in the reprogramming process, compromises efficiency. Our data reveal an unexpected role for the EMT factor SNAI1 in reprogramming somatic cells to pluripotency.

  6. Mesenchymal cells reactivate Snail1 expression to drive three-dimensional invasion programs

    DEFF Research Database (Denmark)

    Rowe, R.G.; Li, X.Y.; Hu, Y.;

    2009-01-01

    Epithelial-mesenchymal transition (EMT) is required for mesodermal differentiation during development. The zinc-finger transcription factor, Snail1, can trigger EMT and is sufficient to transcriptionally reprogram epithelial cells toward a mesenchymal phenotype during neoplasia and fibrosis...

  7. Studies on the survival and development of field-caught snail Lymnaea rubiginosa in the laboratory

    Directory of Open Access Journals (Sweden)

    S Widjajanti

    1998-10-01

    Full Text Available Lymnaea rubiginosa was collected from two habitats in order to observe their survival and growth rate including their egg production, hatching time and the time they needed to reach maturity. One of the habitat is rice fields in Bogor (subdistricts of Ciomas and Ciampea and the other is a pond in Bogor Botanical Garden. In the laboratory those snails were kept in separate aquarium and grouped according to their shell length. The result showed that the longer the snail length the shorter their survival rate and less egg production. Moreover, the snails collected from rice fields were infected with Echinostoma sp. And Chaetogaster sp., while the snails from the pond were only infected with Chaetogaster sp. The hatching time is between 10-14 days, and to reach maturity, with shell length about 1 cm, they need about 6 weeks.

  8. Life history studies and habitat requirements of the apple snail at Lake Woodruff National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study discusses habitat requirements and life history of the apple snail at Lake Woodruff National Wildlife Refuge. A study was initiated during 1971 to gather...

  9. Wet adhesion and adhesive locomotion of snails on anti-adhesive non-wetting surfaces.

    Directory of Open Access Journals (Sweden)

    Neil J Shirtcliffe

    Full Text Available Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted, texture (smooth, rough or granular or wetting property (hydrophilic or hydrophobic via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces.

  10. Wet Adhesion and Adhesive Locomotion of Snails on Anti-Adhesive Non-Wetting Surfaces

    Science.gov (United States)

    Shirtcliffe, Neil J.; McHale, Glen; Newton, Michael I.

    2012-01-01

    Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces. PMID:22693563

  11. Survey of Endangered Tree Snails on Navy-Owned Land in Guam

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objectives of this survey are to determine the location of Guam tree snails on Navy-owned lands in Guam and to identify the location of suitable habitat and...

  12. European glacial relict snails and plants: environmental context of their modern refugial occurrence in southern Siberia

    Czech Academy of Sciences Publication Activity Database

    Horsák, M.; Chytrý, M.; Hájková, Petra; Hájek, M.; Danihelka, Jiří; Horsáková, V.; Ermakov, N.; German, D. A.; Kočí, M.; Lustyk, P.; Nekola, J. C.; Preislerová, Z.; Valachovič, M.

    2015-01-01

    Roč. 44, č. 4 (2015), s. 638-657. ISSN 0300-9483 Institutional support: RVO:67985939 Keywords : glacial relicts * snails * vascular plants Subject RIV: EF - Botanics Impact factor: 2.658, year: 2014

  13. Bioaccumulative and conchological assessment of heavy metal transfer in a soil-plant-snail food chain

    Directory of Open Access Journals (Sweden)

    Nica Dragos V

    2012-06-01

    Full Text Available Abstract Background Copper (Cu, zinc (Zn, cadmium (Cd, and lead (Pb can pose serious threats to environmental health because they tend to bioaccumulate in terrestrial ecosystems. We investigated under field conditions the transfer of these heavy metals in a soil-plant-snail food chain in Banat area, Romania. The main goal of this paper was to assess the Roman snail (Helix pomatia usefulness in environmental monitoring as bioindicator of heavy metal accumulation. Eight sampling sites, selected by different history of heavy metal (HM exposure, were chosen to be sampled for soil, nettle leaves, and newly matured snails. This study also aimed to identify the putative effects of HM accumulation in the environment on phenotypic variability in selected shell features, which included shell height (SH, relative shell height (RSH, and whorl number (WN. Results Significantly higher amounts of HMs were accumulated in snail hepatopancreas and not in foot. Cu, Zn, and Cd have biomagnified in the snail body, particularly in the hepatopancreas. In contrast, Pb decreased when going up into the food chain. Zn, Cd, and Pb correlated highly with each other at all levels of the investigated food chain. Zn and Pb exhibited an effective soil–plant transfer, whereas in the snail body only foot Cu concentration was correlated with that in soil. There were significant differences among sampling sites for WN, SH, and RSH when compared with reference snails. WN was strongly correlated with Cd and Pb concentrations in nettle leaves but not with Cu and Zn. SH was independent of HM concentrations in soil, snail hepatopancreas, and foot. However, SH correlated negatively with nettle leaves concentrations for each HM except Cu. In contrast, RSH correlated significantly only with Pb concentration in hepatopancreas. Conclusions The snail hepatopancreas accumulates high amounts of HMs, and therefore, this organ can function as a reliable biomarker for tracking HM bioavailability

  14. Variant abiotic factors and the infection of Fasciola gigantica larval stages in vector snail Indoplanorbis exustus

    OpenAIRE

    Neha Singh; Pradeep Kumar; Dinesh Kumar Singh

    2012-01-01

    The aquatic environment has numerous physical and chemical parameters that may influence the physiology and maturation rate of parasite found inside the vector snail. It may be possible that abiotic factors (temperature, pH, CO2, O2 and conductivity) and higher population density of snails could promote the transmission of parasite and raise their local abundance. In the present paper, we examined that how these environmental factors affect the transmission of cercaria throughout the year 200...

  15. Consequences of Physical Disturbance by Tadpoles and Snails on Chironomid Larvae

    OpenAIRE

    Gargi Pal; Gautam Aditya; Niladri Hazra

    2014-01-01

    Indirect interactions among community members impact on organisms. The effects of two snails, banded pond snail, Bellamya bengalensis (Lamarck), and Red-rimmed melania, Melanoides tuberculata (Müller), and tadpoles of Asian common toad, Duttaphrynus melanostictus (Schneider), on nonbiting midge larvae, Chironomus striatipennis Kieffer, were observed in experimental microcosm. Decrease in tube number and tube length of midge larvae was observed compared to control condition due to introduction...

  16. The Effect of Aquatic Plant Abundance on Shell Crushing Resistance in a Freshwater Snail

    OpenAIRE

    Johel Chaves-Campos; Coghill, Lyndon M.; García de León, Francisco J.; Johnson, Steven G.

    2012-01-01

    Most of the shell material in snails is composed of calcium carbonate but the organic shell matrix determines the properties of calcium carbonate crystals. It has been shown that the deposition of calcium carbonate is affected by the ingestion of organic compounds. We hypothesize that organic compounds not synthesized by the snails are important for shell strength and must be obtained from the diet. We tested this idea indirectly by evaluating whether the abundance of the organic matter that ...

  17. Venom Variation during Prey Capture by the Cone Snail, Conus textile

    OpenAIRE

    Cecilia A Prator; Murayama, Kellee M.; Schulz, Joseph R.

    2014-01-01

    Observations of the mollusc-hunting cone snail Conus textile during feeding reveal that prey are often stung multiple times in succession. While studies on the venom peptides injected by fish-hunting cone snails have become common, these approaches have not been widely applied to the analysis of the injected venoms from mollusc-hunters. We have successfully obtained multiple injected venom samples from C. textile individuals, allowing us to investigate venom compositional variation during pre...

  18. Wet Adhesion and Adhesive Locomotion of Snails on Anti-Adhesive Non-Wetting Surfaces

    OpenAIRE

    Shirtcliffe, Neil; McHale, Glen; Newton, Michael

    2012-01-01

    Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and th...

  19. [Occurrence of Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda) in Brazil: intermediate snail host of angiostrongyliasis].

    Science.gov (United States)

    Teles, H M; Vaz, J F; Fontes, L R; Domingos, M de F

    1997-06-01

    Achatina fulica, the intermediate snail host of angiostrongyliasis and also an agricultural pest, is being bred in Brazil for human consumption as "escargot". The snail has escaped from its artificial breeding sites and its dispersal in Itariri country, State of S. Paulo, is reported here for the first time. A. fulica is a transmitter of the rat lungworm Angiostrongylus cantonensis, nematode which causes meningoencephalic angiostrongyliasis; the risks of human contamination are commented on. PMID:9515269

  20. The Giant Snail Achatina fulica as a Candidate Species for Advanced Bioregenerative Life Support Systems

    Science.gov (United States)

    Verbitskaya, Olga; Manukovsky, Nickolay; Kovalev, Vladimir

    Maintenance of crew health is of paramount importance for long duration space missions. Weight loss, bone and calcium loss, increased exposure to radiation and oxidative stress are critical concerns that need to be alleviated. Rational nutrition is a resource for mitigating the influence of unfavorable conditions. The insufficiency of vegetarian diet has been examined by the Japanese, Chinese and U.S. developers of bioregenerative life support systems (BLSS). Hence, inclusion of animals such as silkworm in BLSS looks justified. The giant snail is currently under studying as a source of animal food and a species of reducing waste in BLSS. An experimental system to conduct cultivation of giant snail was developed. It was established that there are some reasons to use the giant snails in BLSS. It could be a source of delicious meat. A. fulica is capable of consuming a wide range of feedstuffs including plant residues. Cultivation of snail in the limited volume does not demand the big expenditures of labor. The production of crude edible biomass and protein of A. fulica was 60±15 g and 7±1.8 g respectively per 1 kg of consumed forage (fresh salad leaves, root and leafy tops of carrot). To satisfy daily animal protein needs (30-35 g) a crewman has to consume 260-300 g of snail meat. To produce such amount of snail protein it takes to use 4.3-5.0 kg of plant forage daily. The nutritional composition of A. fulica whole bodies (without shell) and a meal prepared in various ways was quantitatively determined. Protein, carbohydrate, fat acid and ash content percentages were different among samples prepared in various ways. The protein content was highest (68 %) in the dry sample washed with CH3 COOH solution. Taking into consideration the experimental results a conceptual configuration of BLSS with inclusion of giant snail was developed and mass flow rates between compartments were calculated. Keywords: animal food; protein; giant snail; BLSS; conceptual configuration.

  1. Processing of predicted substrates of fungal Kex2 proteinases from Candida albicans, C. glabrata, Saccharomyces cerevisiae and Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Bader Oliver

    2008-07-01

    Full Text Available Abstract Background Kexin-like proteinases are a subfamily of the subtilisin-like serine proteinases with multiple regulatory functions in eukaryotes. In the yeast Saccharomyces cerevisiae the Kex2 protein is biochemically well investigated, however, with the exception of a few well known proteins such as the α-pheromone precursors, killer toxin precursors and aspartic proteinase propeptides, very few substrates are known. Fungal kex2 deletion mutants display pleiotropic phenotypes that are thought to result from the failure to proteolytically activate such substrates. Results In this study we have aimed at providing an improved assembly of Kex2 target proteins to explain the phenotypes observed in fungal kex2 deletion mutants by in vitro digestion of recombinant substrates from Candida albicans and C. glabrata. We identified CaEce1, CA0365, one member of the Pry protein family and CaOps4-homolog proteins as novel Kex2 substrates. Conclusion Statistical analysis of the cleavage sites revealed extended subsite recognition of negatively charged residues in the P1', P2' and P4' positions, which is also reflected in construction of the respective binding pockets in the ScKex2 enzyme. Additionally, we provide evidence for the existence of structural constrains in potential substrates prohibiting proteolysis. Furthermore, by using purified Kex2 proteinases from S. cerevisiae, P. pastoris, C. albicans and C. glabrata, we show that while the substrate specificity is generally conserved between organisms, the proteinases are still distinct from each other and are likely to have additional unique substrate recognition.

  2. Foraging and refuge use by a pond snail: Effects of physiological state, predators, and resources

    Science.gov (United States)

    Wojdak, Jeremy M.

    2009-09-01

    The costs and benefits of anti-predator behavioral responses should be functions of the actual risk of predation, the availability of the prey's resources, and the physiological state of the prey. For example, a food-stressed individual risks starvation when hiding from predators, while a well-fed organism can better afford to hide (and pay the cost of not foraging). Similarly, the benefits of resource acquisition are probably highest for the prey in the poorest state, while there may be diminishing returns for prey nearing satiation. Empirical studies of state-dependent behavior are only beginning, however, and few studies have investigated interactions between all three potentially important factors. Here I present the results of a laboratory experiment where I manipulated the physiological state of pond snails ( Physa gyrina), the abundance of algal resources, and predation cues ( Belostoma flumineum waterbugs consuming snails) in a full factorial design to assess their direct effects on snail behavior and indirect effects on algal biomass. On average, snails foraged more when resources were abundant, and when predators were absent. Snails also foraged more when previously exposed to physiological stress. Snails spent more time at the water's surface (a refuging behavior) in the presence of predation cues on average, but predation, resource levels, and prey state had interactive effects on refuge use. There was a consistent positive trait-mediated indirect effect of predators on algal biomass, across all resource levels and prey states.

  3. The potential utility of nested PCR for investigation ofCoxiella burnetii in Iranian snails

    Institute of Scientific and Technical Information of China (English)

    Mina Dehghani-Samani; Abbas Doosti; Asghar Arshi

    2016-01-01

    Objective: To detect the prevalence ofCoxiella burnetii (C. burnetii) in two species of snails consisted ofLymnaea palustris (L. palustris) andPomacea canaliculata (P. canaliculata) by using nestedPCR method in Chaharmahel Va Bakhtiari Province which is located in the southwest of Iran. Methods:A total of160 snail samples consisted of 100L. palustris and 60P. canaliculata were collected from 4 rice paddy fields in the southwest of Iran between June and August 2014. Snails'DNA was extracted by a genomicDNA purification kit according to the manufacturer's instructions. Detection of the presence ofC. burnetii'sDNA was carried out by using a nested PCR assay with [specific primers outer membrane protein 1 (OMP1)-OMP2 and OMP3-OMP4] targeting the com1 gene. Results: In this study, a total of 160 snail samples were tested and 15 (9.37%) samples were found positive forC. burnetii, 15 samples were positive from theL. palustris and there were no positive samples fromP. canaliculata. Conclusions: Snails are kind of gastropods which seem to be harmless in life, but these small gastropods can be very dangerous for farmers, especially in humid climates. Also,C. burnetii in snails showed that this bacterium can be a factor of transmission of contamination to human beings and animals.

  4. Impact of invasive apple snails on the functioning and services of natural and managed wetlands

    Science.gov (United States)

    Horgan, Finbarr G.; Stuart, Alexander M.; Kudavidanage, Enoka P.

    2014-01-01

    At least 14 species of apple snail (Ampullariidae) have been released to water bodies outside their native ranges; however, less than half of these species have become widespread or caused appreciable impacts. We review evidence for the impact of apple snails on natural and managed wetlands focusing on those studies that have elucidated impact mechanisms. Significant changes in wetland ecosystems have been noted in regions where the snails are established: Two species in particular (Pomacea canaliculata and Pomacea maculata) have become major pests of aquatic crops, including rice, and caused enormous increases in molluscicide use. Invasive apple snails have also altered macrophyte community structure in natural and managed wetlands through selective herbivory and certain apple snail species can potentially shift the balance of freshwater ecosystems from clear water (macrophyte dominated) to turbid (plankton dominated) states by depleting densities of native aquatic plants. Furthermore, the introductions of some apple snail species have altered benthic community structure either directly, through predation, or indirectly, through exploitation competition or as a result of management actions. To date much of the evidence for these impacts has been based on correlations, with few manipulative field or mesocosm experiments. Greater attention to impact monitoring is required, and, for Asia in particular, a landscape approach to impact management that includes both natural and managed-rice wetlands is recommended.

  5. Differences in predatory pressure on terrestrial snails by birds and mammals

    Indian Academy of Sciences (India)

    Zuzanna M Rosin; Paulina Olborska; Adrian Surmacki; Piotr Tryjanowski

    2011-09-01

    The evolution of shell polymorphism in terrestrial snails is a classic textbook example of the effect of natural selection in which avian and mammalian predation represents an important selective force on gene frequency. However, many questions about predation remain unclear, especially in the case of mammals. We collected 2000 specimens from eight terrestrial gastropod species to investigate the predation pressure exerted by birds and mice on snails. We found evidence of avian and mammalian predation in 26.5% and 36.8% of the shells. Both birds and mammals were selective with respect to snail species, size and morphs. Birds preferred the brown-lipped banded snail Cepaea nemoralis (L.) and mice preferred the burgundy snail Helix pomatia L. Mice avoided pink mid-banded C. nemoralis and preferred brown mid-banded morphs, which were neglected by birds. In contrast to mice, birds chose larger individuals. Significant differences in their predatory pressure can influence the evolution and maintenance of shell size and polymorphism of shell colouration in snails.

  6. Differences in predatory pressure on terrestrial snails by birds and mammals.

    Science.gov (United States)

    Rosin, Zuzanna M; Olborska, Paulina; Surmacki, Adrian; Tryjanowski, Piotr

    2011-09-01

    The evolution of shell polymorphism in terrestrial snails is a classic textbook example of the effect of natural selection in which avian and mammalian predation represents an important selective force on gene frequency. However, many questions about predation remain unclear, especially in the case of mammals. We collected 2000 specimens from eight terrestrial gastropod species to investigate the predation pressure exerted by birds and mice on snails. We found evidence of avian and mammalian predation in 26.5% and 36.8% of the shells. Both birds and mammals were selective with respect to snail species, size and morphs. Birds preferred the brown-lipped banded snail Cepaea nemoralis (L.) and mice preferred the burgundy snail Helix pomatia L. Mice avoided pink mid-banded C. nemoralis and preferred brown mid-banded morphs, which were neglected by birds. In contrast to mice, birds chose larger individuals. Significant differences in their predatory pressure can influence the evolution and maintenance of shell size and polymorphism of shell colouration in snails. PMID:21857115

  7. Characteristics of Feeding Preference and Nutrients Utilization of Golden Apple Snail (Pomacea canaliculata on Macrophytes in Paddy Fields

    Directory of Open Access Journals (Sweden)

    Benliang Zhao

    2012-10-01

    Full Text Available Golden apple snail was a harmful invasive gastropod in Asian wetlands. In order to clarify the effect of Pomacea canaliculata on macrophytes in paddy fields, feeding preference and nutrients utilization of snail were studied. Feeding preference of snail was Alternanthera philoxenoides>Monochoria vaginalis>Oryza sativa L. Snail showed a higher approximate digestion coefficient on Oryza sativa L. than that on Monochoria vaginalis. Nitrogen utilization coefficient of snail on Alternanthera philoxenoides was significantly higher than that on Oryza sativa L. Snail exhibited a higher calcium utilization coefficient on Alternanthera philoxenoides and Monochoria vaginalis than that on Oryza sativa L. Oryza sativa L. was not preferred among three plants under the same available and exposure condition.

  8. A Faunistic Survey of Cercariae from Fresh Water Snails: Melanopsis spp. and their Role in Transmission Diseases

    OpenAIRE

    A Farahnak; R Vafaie-Darian; I Mobedi

    2006-01-01

    Snail transmitted diseases are one of the major group of helminth parasitic diseases which have been established by trematode parasites. The larvae of trematodes (cercariae) use the snails as host. The purpose of the present study was to identify of cercariae released from Melanopsis spp. (M. doriae, M. costata, M. praemorsa, and M. nodosa) and evaluate their medical importance. Accordingly, 2, 266 Melanopsis spp. (fresh water snails) were collected from various agriculture canals in the cent...

  9. The Snail Transcription Factor Regulates the Numbers of Neural Precursor Cells and Newborn Neurons throughout Mammalian Life

    OpenAIRE

    Zander, Mark A.; Cancino, Gonzalo I.; Gridley, Thomas; Kaplan, David R.; Miller, Freda D.

    2014-01-01

    The Snail transcription factor regulates diverse aspects of stem cell biology in organisms ranging from Drosophila to mammals. Here we have asked whether it regulates the biology of neural precursor cells (NPCs) in the forebrain of postnatal and adult mice, taking advantage of a mouse containing a floxed Snail allele (Snailfl/fl mice). We show that when Snail is inducibly ablated in the embryonic cortex, this has long-term consequences for cortical organization. In particular, when Snailfl/fl...

  10. In vitro PHYTOTHERAPY OF VECTOR SNAILS BY BINARY COMBINATIONS OF LARVICIDAL ACTIVE COMPONENTS IN EFFECTIVE CONTROL OF FASCIOLIASIS

    OpenAIRE

    Kumari Sunita; Pradeep Kumar; Vinay Kumar Singh; Dinesh Kumar Singh

    2013-01-01

    SUMMARY A food-borne trematode infection fascioliasis is one among common public health problems worldwide. It caused a great economic loss for the human race. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. The life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria inside of the snail Lymnaea acuminata. In vitro toxicity of different binary com...

  11. Lethal and non-lethal effects of multiple indigenous predators on the invasive golden apple snail (Pomacea canaliculata)

    OpenAIRE

    Carlsson, Nils; Kestrup, A; Mårtensson, M.; Nyström, Per

    2004-01-01

    1. We investigated the individual and combined effects of two predators (the climbing perch, Anabas testudineus, and the wetland crab, Esanthelphusa nimoafi) indigenous to wetlands in Laos, on the behaviour and survival of the invasive South American golden apple snail (Pomacea canaliculata). The snail is considered a pest, consuming large amounts of rice and other aquatic vegetation in the region. 2. Snail avoidance reactions to released predator chemical cues were investigated in aquaria wh...

  12. Soil parameters are key factors to predict metal bioavailability to snails based on chemical extractant data

    International Nuclear Information System (INIS)

    Although soil characteristics modulate metal mobility and bioavailability to organisms, they are often ignored in the risk assessment of metal transfer. This paper aims to determine the ability of chemical methods to assess and predict cadmium (Cd), lead (Pb) and zinc (Zn) environmental bioavailability to the land snail Cantareus aspersus. Snails were exposed in the laboratory for 28 days to 17 soils from around a former smelter. The soils were selected for their range of pH, organic matter, clay content, and Cd, Pb and Zn concentrations. The influence of soil properties on environmental availability (estimated using HF-HClO4, EDTA, CaCl2, NH4NO3, NaNO3, free ion activity and total dissolved metal concentration in soil solution) and on environmental bioavailability (modelled using accumulation kinetics) was identified. Among the seven chemical methods, only the EDTA and the total soil concentration can be used to assess Cd and Pb environmental bioavailability to snails (r²adj = 0.67 and 0.77, respectively). For Zn, none of the chemical methods were suitable. Taking into account the influence of the soil characteristics (pH and CEC) allows a better prediction of Cd and Pb environmental bioavailability (r²adj = 0.82 and 0.83, respectively). Even though alone none of the chemical methods tested could assess Zn environmental bioavailability to snails, the addition of pH, iron and aluminium oxides allowed the variation of assimilation fluxes to be predicted. A conceptual and practical method to use soil characteristics for risk assessment is proposed based on these results. We conclude that as yet there is no universal chemical method to predict metal environmental bioavailability to snails, and that the soil factors having the greatest impact depend on the metal considered. - Highlights: ► New approach to identify chemical methods able to predict metal bioavailability to snails. ► Bioavailability of cadmium, lead and zinc to snails was determined by assessing

  13. SNAIL transcription factor increases the motility and invasive capacity of prostate cancer cells.

    Science.gov (United States)

    Osorio, Luis A; Farfán, Nancy M; Castellón, Enrique A; Contreras, Héctor R

    2016-01-01

    The incidence and mortality rates of prostate cancer (PCa) are increasing, and PCa is almost the second‑leading cause of cancer‑associated mortality in men. During tumor progression, epithelial cells decrease the number of adhesion molecules, change their polarity and position, rearrange their cytoskeleton and increase their migratory and invasive capacities. These changes are known under the concept of epithelial‑mesenchymal transition (EMT). EMT is characterized by an upregulation of certain transcription factors, including SNAIL1, which represses genes that are characteristic of an epithelial phenotype, including E‑cadherin, and indirectly increase the expression levels of genes, which are associated with the mesenchymal phenotype. It has been suggested that the transcription factor, SNAIL1, decreases the proliferation and increases the migratory and invasive capacities of PCa cell lines. The present study was performed using LNCaP and PC3 cell lines, in which the expression levels of SNAIL1 were increased or silenced through the use of lentiviral vectors. The expression levels of EMT markers were quantified using reverse transcription‑quantitative polymerase chain reaction and western blot analysis. In addition, cell survival was analyzed using an MTS assay; cell proliferation was examined using an antibody targeting Ki‑67; migration on plates with 8 µm pores to allow the passage of cells; and invasiveness was analyzed using a membrane chamber covered in dried basement membrane matrix solution. The levels of apoptosis were determined using a Caspase 3/7 assay containing a substrate modified by caspases 3 and 7. The results demonstrated that the overexpression and silencing of SNAIL1 decreased cell proliferation and survival. However, the overexpression of SNAIL1 decreased apoptosis, compared with cells with the SNAIL1‑silenced cells, in which cell apoptosis increased. The migration and invasive capacities increased in the cells overexpressing

  14. Overexpression of Snail is associated with lymph node metastasis and poor prognosis in patients with gastric cancer

    Directory of Open Access Journals (Sweden)

    Shin Na Ri

    2012-11-01

    Full Text Available Abstract Background Epithelial–mesenchymal transition (EMT plays a significant role in tumor progression and invasion. Snail is a known regulator of EMT in various malignant tumors. This study investigated the role of Snail in gastric cancer. Methods We examined the effects of silenced or overexpressed Snail using lenti-viral constructs in gastric cancer cells. Immunohistochemical analysis of tissue microarrays from 314 patients with gastric adenocarcinoma (GC was used to determine Snail’s clinicopathological and prognostic significance. Differential gene expression in 45 GC specimens with Snail overexpression was investigated using cDNA microarray analysis. Results Silencing of Snail by shRNA decreased invasion and migration in GC cell lines. Conversely, Snail overexpression increased invasion and migration of gastric cancer cells, in line with increased VEGF and MMP11. Snail overexpression (≥75% positive nuclear staining was also significantly associated with tumor progression (P P = 0.002, lymphovascular invasion (P = 0.002, and perineural invasion (P = 0.002 in the 314 GC patients, and with shorter survival (P = 0.023. cDNA microarray analysis revealed 213 differentially expressed genes in GC tissues with Snail overexpression, including genes related to metastasis and invasion. Conclusion Snail significantly affects invasiveness/migratory ability of GCs, and may also be used as a predictive biomarker for prognosis or aggressiveness of GCs.

  15. Overexpression of Snail is associated with lymph node metastasis and poor prognosis in patients with gastric cancer

    International Nuclear Information System (INIS)

    Epithelial–mesenchymal transition (EMT) plays a significant role in tumor progression and invasion. Snail is a known regulator of EMT in various malignant tumors. This study investigated the role of Snail in gastric cancer. We examined the effects of silenced or overexpressed Snail using lenti-viral constructs in gastric cancer cells. Immunohistochemical analysis of tissue microarrays from 314 patients with gastric adenocarcinoma (GC) was used to determine Snail’s clinicopathological and prognostic significance. Differential gene expression in 45 GC specimens with Snail overexpression was investigated using cDNA microarray analysis. Silencing of Snail by shRNA decreased invasion and migration in GC cell lines. Conversely, Snail overexpression increased invasion and migration of gastric cancer cells, in line with increased VEGF and MMP11. Snail overexpression (≥75% positive nuclear staining) was also significantly associated with tumor progression (P < 0.001), lymph node metastases (P = 0.002), lymphovascular invasion (P = 0.002), and perineural invasion (P = 0.002) in the 314 GC patients, and with shorter survival (P = 0.023). cDNA microarray analysis revealed 213 differentially expressed genes in GC tissues with Snail overexpression, including genes related to metastasis and invasion. Snail significantly affects invasiveness/migratory ability of GCs, and may also be used as a predictive biomarker for prognosis or aggressiveness of GCs

  16. Estudios morfométricos y biológicos de xifidiocercarias (Trematoda) provenientes de la infección natural de Lymnaea columella Say, 1817 (Basommatophora, Lymaenidae) y Biomphalaria tenagophila Orbigny, 1835 (Basommatophora, Planorbidae) recolectados en Miracatu, Estado São Paulo, Brasil Morphometric and biological studies on xiphidiocercariae (Trematoda) recovered from Lymnaea columella Say, 1817 (Basommatophora, Lymnaeidae) and Biomphalaria tenagophila Orbigny, 1835 (Basommatophora, Planorbidae) from Miracatu, São Paulo State, Brazil

    OpenAIRE

    Gílcia A de Carvahlo; Ueta, Marlene T.; Carlos F. S. de Andrade

    2001-01-01

    Two species of xiphidiocercariae probably belonging to the family Haematoloechidae (Trematoda) emerging from Lymnaea columella (Basommatophora, Lymnaeidae) and Biomphalaria tenagophila (Basommatophora, Planorbidae) collected in Miracatu City, São Paulo State, Brazil, between September 1996 and February 1999 were described. The xiphidiocercariae eliminated by L. columella presented a terminal membrane in the tail that morphologicaly differenciated them from those obtained from B. tenagophila. ...

  17. Thermal tolerance and climate warming sensitivity in tropical snails.

    Science.gov (United States)

    Marshall, David J; Rezende, Enrico L; Baharuddin, Nursalwa; Choi, Francis; Helmuth, Brian

    2015-12-01

    Tropical ectotherms are predicted to be especially vulnerable to climate change because their thermal tolerance limits generally lie close to current maximum air temperatures. This prediction derives primarily from studies on insects and lizards and remains untested for other taxa with contrasting ecologies. We studied the HCT (heat coma temperatures) and ULT (upper lethal temperatures) of 40 species of tropical eulittoral snails (Littorinidae and Neritidae) inhabiting exposed rocky shores and shaded mangrove forests in Oceania, Africa, Asia and North America. We also estimated extremes in animal body temperature at each site using a simple heat budget model and historical (20 years) air temperature and solar radiation data. Phylogenetic analyses suggest that HCT and ULT exhibit limited adaptive variation across habitats (mangroves vs. rocky shores) or geographic locations despite their contrasting thermal regimes. Instead, the elevated heat tolerance of these species (HCT = 44.5 ± 1.8°C and ULT = 52.1 ± 2.2°C) seems to reflect the extreme temperature variability of intertidal systems. Sensitivity to climate warming, which was quantified as the difference between HCT or ULT and maximum body temperature, differed greatly between snails from sunny (rocky shore; Thermal Safety Margin, TSM = -14.8 ± 3.3°C and -6.2 ± 4.4°C for HCT and ULT, respectively) and shaded (mangrove) habitats (TSM = 5.1 ± 3.6°C and 12.5 ± 3.6°C). Negative TSMs in rocky shore animals suggest that mortality is likely ameliorated during extreme climatic events by behavioral thermoregulation. Given the low variability in heat tolerance across species, habitat and geographic location account for most of the variation in TSM and may adequately predict the vulnerability to climate change. These findings caution against generalizations on the impact of global warming across ectothermic taxa and highlight how the consideration of nonmodel animals, ecological transitions

  18. Lead reduces shell mass in juvenile garden snails (Helix aspersa)

    International Nuclear Information System (INIS)

    A high Pb diet causes differential depression of juvenile shell mass in populations of Helix. - In an earlier paper examining inherited tolerance to Pb, the shell growth of laboratory-bred offspring of Helix aspersa from contaminated sites was compared with that of juveniles from naieve populations on dosed and undosed diets. Eight-week-old snails were fed either 500 μg g-1 Pb or a control food in competitive trials between two populations. In the first series of trials, a parental history of exposure to Pb did not confer any advantage to either of two populations (BI and MI) competing with a naieve population (LE), whether Pb was present in the diet or not. However, in the analysis of their metal concentrations reported here, LE are found to retain higher levels of Pb in the soft tissues than either BI or MI. Compared to their siblings on the unleaded diet, dosed LE and BI juveniles had lower soft tissue concentrations of Ca and Mg. Although the growth in shell height is unaffected by diet, LE and BI juveniles build lighter shells on the Pb-dosed diet, achieving around 75% of the shell mass of their controls. In contrast, the shell weights of dosed MI juveniles are depressed by only 15% and show no change in the essential metal concentrations of their soft tissues. A second experiment using five populations fed only the dosed food show that the shell weight/soft tissue weight ratios are comparable to the dosed snails of the previous experiment. Building a lighter shell thus appears to be the common response of all Helix populations to a high Pb diet, at least amongst juveniles. The reduction in its mass means that less Ca and Mg is added to the shell and, along with the lowered soft tissue concentrations observed in some populations, may be a consequence of an increased effort to excrete Pb. The possibility that the MI population shows a genotypic adaptation, perhaps as some form of modification of its Ca metabolism, is briefly discussed

  19. Multilocus Microsatellite Markers for Molecular Typing of Candida glabrata: Application to Analysis of Genetic Relationships between Bloodstream and Digestive System Isolates▿

    OpenAIRE

    Enache-Angoulvant, A.; BOURGET, M; S Brisse; Stockman-Pannier, C.; Diancourt, L.; François, N.; Rimek, D.; Fairhead, C; Poulain, Daniel; Hennequin, C.

    2010-01-01

    Candida glabrata has emerged as the second most common etiologic agent, after Candida albicans, of superficial and invasive candidiasis in adults. Strain typing is essential for epidemiological investigation, but easy-to-use and reliable typing methods are still lacking. We report the use of a multilocus microsatellite typing method with a set of eight markers on a panel of 180 strains, including 136 blood isolates from hospitalized patients and 34 digestive tract isolates from nonhospitalize...

  20. In Vitro Activities of Terbinafine in Combination with Fluconazole, Itraconazole, Voriconazole, and Posaconazole against Clinical Isolates of Candida glabrata with Decreased Susceptibility to Azoles

    OpenAIRE

    Perea, Sofia; Gonzalez, Gloria; Fothergill, Annette W.; Sutton, Deanna A.; Rinaldi, Michael G.

    2002-01-01

    A checkerboard microdilution method, performed according to the recommendations of the National Committee for Clinical Laboratory Standards, was used to study the in vitro interaction of terbinafine (TRB) with fluconazole (FLU), itraconazole (ITRA), voriconazole (VRC), and posaconazole (PSZ) in 24 isolates of Candida glabrata with decreased susceptibility to azoles isolated from the oral cavities of human immunodeficiency virus patients. Synergy, defined as a fractional inhibitory concentrati...

  1. Viral Preprotoxin Signal Sequence Allows Efficient Secretion of Green Fluorescent Protein by Candida glabrata, Pichia pastoris, Saccharomyces cerevisiae, and Schizosaccharomyces pombe

    OpenAIRE

    Eiden-Plach, Antje; Zagorc, Tatjana; Heintel, Tanja; Carius, Yvonne; Breinig, Frank; Manfred J Schmitt

    2004-01-01

    Besides its importance as model organism in eukaryotic cell biology, yeast species have also developed into an attractive host for the expression, processing, and secretion of recombinant proteins. Here we investigated foreign protein secretion in four distantly related yeasts (Candida glabrata, Pichia pastoris, Saccharomyces cerevisiae, and Schizosaccharomyces pombe) by using green fluorescent protein (GFP) as a reporter and a viral secretion signal sequence derived from the K28 preprotoxin ...

  2. Estudos preliminares com bromoacetamida, um novo moluscicida

    Directory of Open Access Journals (Sweden)

    Naftale Katz

    1985-09-01

    Full Text Available A bromoacetamida tem sido testada como moluscicida na República Popular da China, para tratamento de criadouros de Oncomelania, hospedeiro do Schistosoma japonicum, com bons resultados. O produto é solúvel em água, o que simplifica seu uso. Foram feitos ensaios biológicos preliminares deste produto em caramujos adultos (Biomphalaria glabrata, B. tenagophila e B. straminea, recém-eclodidos e desovas. Paralelamente foram feitos ensaios com o pentaclorofenol para avaliar a suscetibilidade dos caramujos. O produto foi testado também sobre peixes, Lebistes reticulatus. Os moluscos testados mediam 8-10 mm de diâmetro; os recém-eclodidos tinham 1-3 dias de idade e as desovas 0-1 dia de idade. A temperatura da água durante os experimentos variou de 24,3 a 27,0°C. O produto foi ativo para caramujos adultos, recém-eclodidos e desovas, em concentrações em tomo de 1 a 4 ppm. Para os peixes o produto foi menos tóxico do que para os caramujos (CLço 7,5 ppm. Estes resultados indicam que a bromoacetamida apresenta propriedades moluscicidas promissoras para o controle da Biomphalaria spp.Bromocetamide has been tested as molluscicide, with good results, in the People's Republic of China, on Oncomelania, host of Schistosoma japonicum. We have conducted preliminary assays with bromoacetamide on adult snails (B. glabrata, B. tenagophila and B. straminea, newly hatched smails and egg-masses. This product has been also tested on fishes (Lebistes reticulatus. Comparative assays have been made with pentaclorophenol to evaluate the suceptibility of the snails. Snails tested had a diameter of 8-10 mm; the newly hatched were 1-3 days old and the eggs-masses. 0-1 day old. The temperature of the water varied from 24.3 to 27.5° C. Bromoacetamide was active on adult and newly hatched snails and egg-masses, in concentrations from 1-4ppm. The product was less toxic for jish (LC90 = 7,5 ppm. These results indicate that bromoacetamide has promising molluscicide

  3. Phylogeography and conservation genetics of the Iowa pleistocene snail.

    Science.gov (United States)

    Ross, T K

    1999-09-01

    The Iowa Pleistocene snail, Discus macclintocki, is an endangered species that survives only in relictual populations on algific (cold-air) talus slopes in northeast Iowa and northwest Illinois in the central region of the USA. These populations are believed to have been isolated since the temperatures began to warm at the end of the last glacial period around 16 500 years ago. DNA sequencing of the 16s rRNA gene of the mitochondria was used to determine the genetic relationship among 10 populations and the genetic diversity within these populations. Genetic diversity is extremely high within this species with 40 haplotypes spread across the 10 populations sampled within a 4000 km2 region. Phylogenetic analyses showed that haplotypes formed monophyletic groups by the watershed on which they were found, suggesting that watersheds were important historical avenues of gene flow. Genetic distances were strongly related to the geographical distance among all populations, but this relationship was dependent on the scale being considered. PMID:10564443

  4. Prostaglandin E2 accelerates invasion by upregulating Snail in hepatocellular carcinoma cells.

    Science.gov (United States)

    Zhang, Min; Zhang, Hai; Cheng, Shanyu; Zhang, Dengcai; Xu, Yan; Bai, Xiaoming; Xia, Shukai; Zhang, Li; Ma, Juan; Du, Mingzhan; Wang, Yipin; Wang, Jie; Chen, Meng; Leng, Jing

    2014-07-01

    Our previous studies showed that prostaglandin E2 (PGE2) promotes hepatoma cell growth and migration, as well as invasion; however, the precise mechanism remains elusive. Snail and p65 protein levels were detected in human samples with hepatocellular carcinoma (HCC) by immunohistochemistry (IHC) staining. HCC cell lines (Huh-7 and Hep3B) were used for in vitro experiments. PGE2/Akt/NF-κB pathway was investigated in Huh-7 and Hep3B cells after treatment with PGE2, EP4 receptor (EP4R) agonist, Akt inhibitor, and NF-κB inhibitor, respectively, by real-time reverse transcription (RT)-PCR, Western blotting, and immunofluorescence (IF) staining. In vitro cell invasion assay was performed to evaluate the effect of PGE2 on tumor invasiveness. Knockdown of EP4R was carried out in Huh-7 cells through plasmid-based small interfering RNA (siRNA) approach to confirm the regulation of PGE2 on Snail by EP4R. Dual luciferase reporter assay was performed to assess Snail promoter activity in Huh-7 cell after treatment with EP4R agonist. We found that the protein levels of Snail were higher in HCC tissues than those in control and that PGE2 and EP4R agonist treatment significantly increased Snail expression in Huh-7 and Hep3B cells. EP4R agonist also profoundly promoted invasiveness of Huh-7 cells. Knockdown of the EP4R by siRNA completely blocked the PGE2-induced upregulation of Snail expression and reduced invasiveness of Huh-7 cells. We failed to find that EP4R-induced upregulation of Snail was reversed by inhibition of cAMP response element-binding protein (CREB), a canonical downstream target of EP4R. Alternatively, EP4R agonist treatment significantly increased the levels of phosphorylated EGFR and Akt both in Huh-7 and Hep3B cells. AG1478, an EGFR inhibitor, blocked the phosphorylation of Akt. The levels of phosphorylated IκB increased in Huh-7 cells after treatment with EP4R agonist for 30 min. The levels of phosphorylated p65 started to increase in Huh-7 cells treated

  5. A new biosurfactant produced by Candida glabrata UCP 1002: characteristics of stability and application in oil recovery

    Directory of Open Access Journals (Sweden)

    Juliana Moura de Luna

    2009-08-01

    Full Text Available The production of a new biosurfactant by Candida glabrata UCP1002 was studied to evaluate the influence of the concentration of the cotton seed oil, glucose and yeast extract. The dynamics of the growth and surfactant production were showed for all the cultivation conditions studied. The best emulsification of the n-hexadecane, quantified by the emulsifying index was observed in the medium containing 7.5% cotton seed oil, 5% glucose and 0.3% yeast extract. The isolated biosurfactant showed a CMC of 2.5% and the surface tension at that point showed to be 31mN/m. The potential application of the biosurfactant in oil recovery from the sand, in acid and alkaline environments and over exposure to high salinity and different temperatures was demonstrated by the percentage of oil removal and by the stability of the surface tension, respectively.A produção de um novo biossurfactante por Candida glabrata UCP1002 foi inicialmente investigada com a finalidade de avaliar a influência da concentração dos substratos óleo de algodão, glicose e extrato de levedura. As cinéticas de crescimento e de produção do surfactante foram demonstradas para todas as condições de cultivo testadas. A melhor emulsificação do nhexadecano, quantificada através do índice de emulsificação foi observada na condição de cultivo contendo 7,5% de óleo de algodão, 5% de glicose e 0,3% de extrato de levedura. O biossurfactante produzido apresentou uma concentração micelar crítica de 2,5%, sendo a tensão superficial nesse ponto de 31mN/m. O potencial de aplicação do biossurfactante na recuperação de óleo de areia contaminada, em condições ácidas e alcalinas, bem como sob exposição a altas salinidades e diferentes temperaturas, foram demonstrados com base no percentual de remoção do óleo e na estabilidade da tensão superficial, respectivamente.

  6. An overview of freshwater snails in Asia with main focus on Vietnam.

    Science.gov (United States)

    Madsen, H; Hung, N M

    2014-12-01

    Freshwater snails have received much attention for their role as intermediate hosts for trematodes causing disease in people and animals such as schistosomiasis and various food-borne trematodes. While effective medical treatment exists for some of these diseases there is need for preventive measures to reduce transmission, e.g. control of intermediate hosts because transmission patterns are often complicated due to presence of reservoir final hosts. In order to implement control measures against the intermediate host snails with minimal impact on the freshwater ecosystems and their biodiversity, a profound knowledge on transmission patterns of the trematodes is required and this is partly related to distribution, habitat preferences, and seasonal variation in density of the intermediate host species. Identification of snail species can be problematic on the basis of morphological and anatomical characters alone as some species show morphological plasticity and similarly morphological differentiation of cercariae found in snails may be difficult and this could lead to biased perceptions of intermediate host spectra and transmission patterns. In this paper, we give an overview of the snail families and their medical and veterinary importance in Asia but with main focus on Vietnam. PMID:25149356

  7. Reprint of "An overview of freshwater snails in Asia with main focus on Vietnam".

    Science.gov (United States)

    Madsen, H; Hung, N M

    2015-01-01

    Freshwater snails have received much attention for their role as intermediate hosts for trematodes causing disease in people and animals such as schistosomiasis and various food-borne trematodes. While effective medical treatment exists for some of these diseases there is need for preventive measures to reduce transmission, e.g. control of intermediate hosts because transmission patterns are often complicated due to presence of reservoir final hosts. In order to implement control measures against the intermediate host snails with minimal impact on the freshwater ecosystems and their biodiversity, a profound knowledge on transmission patterns of the trematodes is required and this is partly related to distribution, habitat preferences, and seasonal variation in density of the intermediate host species. Identification of snail species can be problematic on the basis of morphological and anatomical characters alone as some species show morphological plasticity and similarly morphological differentiation of cercariae found in snails may be difficult and this could lead to biased perceptions of intermediate host spectra and transmission patterns. In this paper, we give an overview of the snail families and their medical and veterinary importance in Asia but with main focus on Vietnam. PMID:25446169

  8. The Drosophila gene escargot encodes a zinc finger motif found in snail-related genes.

    Science.gov (United States)

    Whiteley, M; Noguchi, P D; Sensabaugh, S M; Odenwald, W F; Kassis, J A

    1992-02-01

    Two independent P-element enhancer detection lines were obtained that express lacZ in a pattern of longitudinal stripes early in germband elongation. In this paper, molecular and genetic characterization of a gene located near these transposons is presented. Sequence analysis of a cDNA clone from the region reveals that this gene has a high degree of similarity with the Drosophila snail gene (Boulay et al., 1987). The sequence similarity extends over 400 nucleotides, and includes a region encoding five tandem zinc finger motifs (72% nucleotide identity; 76% amino acid identity). This region is also conserved in the snail homologue from Xenopus laevis (76% nucleotide identity; 83% amino acid identity) (Sargent and Bennett, 1990). We have named the Drosophila snail-related gene escargot (esg), and the region of sequence conservation common to all three genes the 'snailbox'. A number of Drosophila genomic DNA fragments cross-hybridize to a probe from the snailbox region suggesting that snail and escargot are members of a multigene family. The expression pattern of escargot is dynamic and complex. Early in germband elongation, escargot RNA is expressed in a pattern of longitudinal stripes identical to the one observed in the two enhancer detection lines. Later in development, escargot is expressed in cells that will form the larval imaginal tissues, escargot is allelic with l(2)35Ce, an essential gene located near snail in the genome. PMID:1571289

  9. Snail-type zinc finger proteins prevent neurogenesis in Scutoid and transgenic animals of Drosophila.

    Science.gov (United States)

    Fuse, N; Matakatsu, H; Taniguchi, M; Hayashi, S

    1999-10-01

    Scutoid is a classical dominant gain-of-function mutation of Drosophila, causing a loss of bristles and roughening of the compound eye. Previous genetic and molecular analyses have shown that Scutoid is associated with a chromosomal transposition resulting in a fusion of no-oceli and snail genes. How this gene fusion event leads to the defects in neurogenesis was not known until now. Here have found that snail is ectopically expressed in the eye-antennal and wing imaginal discs in Scutoid larvae, and that this expression is reduced in Scutoid revertants. We have also shown that the expressivity of Scutoid is enhanced by zeste mutations. snail and escargot encode evolutionarily conserved zinc-finger proteins involved in the development of mesoderm and limbs. Snail and Escargot proteins share a common target DNA sequence with the basic helix-loop-helix (bHLH) type proneural gene products. When expressed in the developing external sense organ precursors of the thorax and the eye, these proteins cause a loss of mechanosensory bristles in the thorax and perturbed the development of the compound eye. Such phenotypes resemble those associated with Scutoid. Furthermore, the effect of ectopic Escargot on bristle development is antagonized by coexpression of the bHLH gene asense. Thus, our results suggest that the Scutoid phenotype is due to an ectopic snail expression under the control of no-oceli enhancer, antagonizing neurogenesis through its inhibitory interaction with bHLH proteins. PMID:10552298

  10. Diet control on carbon isotopic composition of land snail shell carbonate

    Institute of Scientific and Technical Information of China (English)

    LIU ZongXiu; GU ZhaoYan; WU NaiQin; XU Bing

    2007-01-01

    Carbon isotope compositions for both the carbonate shells and soft bodies (organic tissue) of living land snails collected mostly from the Loess Plateau, China have been measured. The result shows that δ13C values range from -13.1‰ to -4.3‰ for the aragonite shell samples and from -26.8‰ to -18.0‰ for the soft body samples. Although the shells are enriched in 13C relative to the bodies averagely by 14.2(±0.8)‰, the shell δ13Ca values are closely correlated to the body δ13Corg values, expressed as δ13Ca = 1.021 δ13Corg + 14.38 (R = 0.965; N = 31). This relationship indicates that δ13Ca is primarily a function of the isotopic composition of the snail diets since previous studies have proved that the snail body is the same as their food in carbon isotope composition. In other words, carbon isotope compo-sition of the carbonate shell can be used as a proxy to estimate the dietary 13C abundance of the land snails. The data also support that the 13C enrichment of the carbonate shells results mainly from the equilibrium fractionations between the metabolic CO2, HCO3- in the hemolymph and shell aragonite, and partially from kinetic fractionations when snail shells form during their activity.

  11. NUTRITIONAL VALUE OF CHICKEN OFFAL AS REPLACEMENT FOR LOCAL FISH MEAL IN GROWING SNAILS

    Directory of Open Access Journals (Sweden)

    A OMOLE

    2009-03-01

    Full Text Available A total of ninety six growing snails of mean weight 91.23±2.4g were used to determine the effects of partial or total replacement of local fish meal, a source of protein but expensive to a less expensive, alternative source, chicken offal in the diet of growing snails. Completely randomized design was used for the study. The feeding trial had four treatments, C1, C2, C3 and C4 in which fish meal fraction of the diets was replaced at 0, 50, 75 and 100% with chicken offal respectively. The parameters taken were weight gain, feed intake. Feed conversion ratio, total feed cost, and cost per weight gain were calculated. The trial lasted for twelve weeks. Significant differences were not observed in the mean weekly feed intake of the snails in all the treatments. The mean weight gain in all the treatments were not significantly influenced by the inclusion of chicken offal in the diet (P>0.005. Total feed cost and cost/weight gain reduced as the level of the chicken offal increased while the lowest cost/weight gain was observed in C4. The inclusion of Chicken offal in all the diets had no detrimental effect on the snails in all the treatments. Based on the present results chicken offal could replace local fish meal in the diet of growing snail up to 100% and hereby reduce feed cost

  12. Fascioliasis Control: In Vivo and In Vitro Phytotherapy of Vector Snail to Kill Fasciola Larva

    Directory of Open Access Journals (Sweden)

    Kumari Sunita

    2011-01-01

    Full Text Available Snail is one of the important components of an aquatic ecosystem, it acts as intermediate host of Fasciola species. Control of snail population below a certain threshold level is one of the important methods in the campaign to reduce the incidence of fascioliasis. Life cycle of the parasite can be interrupted by killing the snail or Fasciola larva redia and cercaria in the snail body. In vivo and in vitro toxicity of the plant products and their active component such as citral, ferulic acid, umbelliferone, azadirachtin, and allicin against larva of Fasciola in infected snail Lymnaea acuminata were tested. Mortality of larvae were observed at 2 h, 4 h, 6 h, and 8 h, of treatment. In in vivo treatment, azadirachtin caused highest mortality in redia and cercaria larva (8 h, LC50 0.11, and 0.05 mg/L whereas in in vitro condition allicin was highly toxic against redia and cercaria (8 h, LC50 0.01, and 0.009 mg/L. Toxicity of citral was lowest against redia and cercaria larva.

  13. Attraction to amino acids by Lymnaea acuminata, the snail host of Fasciola species

    Directory of Open Access Journals (Sweden)

    Tiwari F.

    2004-01-01

    Full Text Available Adult Lymnaea acuminata (average length 20-22 mm were collected locally from lakes and low-lying submerged fields from Gorakhpur. The chemoattraction studies were made in round glass aquaria measuring 30 cm in diameter and filled to a depth of 10 mm with 500 ml dechlorinated tap water. Each aquarium was divided into four concentric zones. At the starting time of the assay 10 snails were placed on the circumference of outermost zone 0. Snail attractant pellets (SAP were added simultaneously in the center of central zone 3. SAP of different amino acids were prepared at concentrations of 10, 20, 50, 80 and 100 mM/2% agar solution and, subsequently, spread to a uniform thickness of 5 mm. After cooling, SAP were cut in small pieces of 5 mm in diameter. Lymnaea acuminata's attraction to amino acids was studied using different amino acid concentrations in SAP. Pellets containing amino acids with non-polar R groups (proline and tryptophan, a charged polar group (arginine and uncharged polar R groups (serine, citrulline and asparagine were tested. The snails were more attracted to the uncharged polar R group amino acid serine than to other groups of amino acids. The preferred amino acid concentration was 80 mM. The attraction of snails to different amino acids was concentration dependent. Snails could discriminate amongst the different amino acids at > or = 50 mM.

  14. Dynamic of population-dynamics in a medically important snail species Lymnaea (Radix Luteola (Lamarck

    Directory of Open Access Journals (Sweden)

    T. K. Misra

    1993-09-01

    Full Text Available The life-cycle parameters of the snail Lymnaea (Radix luteola and the factors influencing the same have been studied under laboratory conditions. Ins each month, from July 1990 to June 1991, a batch of 100 zero-day old individual were considered for studies. The snails of April batch survived for 19.42 days while those in December batch survived for 87.45 days. The May batch individual though survived for 65.67 days gained maximum shell size (15.84 mm in length and body weight (419.87 mg. All individuals of April batch died prior to attainment of sexual maturity. In the remaining 11 batches the snails became sexually mature between 32 and 53 days. At this stage, they were with varying shell lengths, 9.3 mm to 13,11 mm in respect to batches. The reproduction period varied from 1-67 days. An individual laid, on an average, 0,25 (March batch to 443.67 (May batch eggs in its life-span. A batch of such snails would leave 24312, 22520, 720268, 80408, 76067, 418165, 214, 9202, 0, 0, 2459386 and 127894 individuals at the end of 352nd day. Since the environmental conditions were almost similar the 'dynamic' of population dynamics seems to be involved with the 'strain' of the snail individuals of the batches concerned.

  15. Global Assessment of Schistosomiasis Control Over the Past Century Shows Targeting the Snail Intermediate Host Works Best

    Science.gov (United States)

    Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lopez, Melina; Lafferty, Kevin D.; Kuris, Armand M.; Rickards, Chloe; De Leo, Giulio A.

    2016-01-01

    Background Despite control efforts, human schistosomiasis remains prevalent throughout Africa, Asia, and South America. The global schistosomiasis burden has changed little since the new anthelmintic drug, praziquantel, promised widespread control. Methodology We evaluated large-scale schistosomiasis control attempts over the past century and across the globe by identifying factors that predict control program success: snail control (e.g., molluscicides or biological control), mass drug administrations (MDA) with praziquantel, or a combined strategy using both. For data, we compiled historical information on control tactics and their quantitative outcomes for all 83 countries and territories in which: (i) schistosomiasis was allegedly endemic during the 20th century, and (ii) schistosomiasis remains endemic, or (iii) schistosomiasis has been "eliminated," or is "no longer endemic," or transmission has been interrupted. Principal Findings Widespread snail control reduced prevalence by 92 ± 5% (N = 19) vs. 37 ± 7% (N = 29) for programs using little or no snail control. In addition, ecological, economic, and political factors contributed to schistosomiasis elimination. For instance, snail control was most common and widespread in wealthier countries and when control began earlier in the 20th century. Conclusions/Significance Snail control has been the most effective way to reduce schistosomiasis prevalence. Despite evidence that snail control leads to long-term disease reduction and elimination, most current schistosomiasis control efforts emphasize MDA using praziquantel over snail control. Combining drug-based control programs with affordable snail control seems the best strategy for eliminating schistosomiasis. PMID:27441556

  16. 8,15-epoxylabdane and norlabdane diterpenoids from Eragrostis viscosa.

    Science.gov (United States)

    Sebastião, N'Soki N; Cordeiro, Inês J S; dos Santos, Aldenir F; Gaspar, Jorge F; Martins, Célia; Rueff, José; Diakanamwa, Carlos; Sant'Ana, Antônio E G; de Mendonça, Dina I M D

    2010-05-01

    Four labdanes with a 8alpha,15-epoxy ring (8alpha,15-epoxylabdan-16beta-oic acid; 8alpha,15-epoxy-16-norlabdan-13-one; 8alpha,15-epoxy-16-norlabdane; and 16-acetoxy-8alpha,15-epoxylabdane) and the known compound ambreinolide were isolated from the hexane extract of the aerial parts of the grass Eragrostis viscosa. The structures of all compounds were established based on spectroscopic data and the X-ray analysis of 8alpha,15-epoxy-16-norlabdan-13-one. The hexane extract presented moderate activity against the snail Biomphalaria glabrata. 8alpha,15-Epoxylabdan-16beta-oic acid showed no mutagenic activity for doses up to 1000 microg/plate and no significant clastogenic activity for doses up to 100 microg/ml. PMID:20189613

  17. Dicty_cDB: Contig-U12334-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 2.0 %: nuclear 4.0 %: plasma membrane 4.0 %: vesicles of secretory system >> prediction for Contig-U12334-1 is... 36 5.5 6 ( ES491624 ) HP00332 Biomphalaria glabrata resistant snail (BS... 38 7....pho melanesiensis BI429... 40 0.37 ( P20584 ) RecName: Full=Phosphate-repressible acid pho...bacter ruber DSM 13855, c... 46 0.004 AM039952_2700( AM039952 |pid:none) Xanthomonas campestris pv. vesi...0.29 AM910995_435( AM910995 |pid:none) Plasmodium knowlesi strain H chr... 40 0.29 CP000716_1735( CP000716 |pid:none) Thermosi

  18. Search for antifungal, molluscicidal and larvicidal compounds from African medicinal plants.

    Science.gov (United States)

    Marston, A; Maillard, M; Hostettmann, K

    1993-03-01

    African medicinal plants provide a rich source of biologically-active natural products. By the use of simple bioassays in conjunction with an approach involving bioactivity guided fractionation, it is possible to isolate novel compounds with interesting properties. Several hundred plant extracts have been submitted to different screens, including bioautography on TLC plates with the fungi Cladosporium cucumerinum and Candida albicans. Among the other test systems are a bioassay for molluscicidal activity with the schistosomiasis-transmitting snail Biomphalaria glabrata and a benchtop assay for larvicidal activity with larvae of the mosquito Aedes aegypti, the vector of yellow fever. Using a variety of modern separation techniques, a number of compounds with activity in these bioassays have been isolated. These include prenylated xanthones, tetracyclic phenols and saponins. The role of saponins and saponin-containing plants in the control of schistosomiasis is outlined. PMID:8510471

  19. Dicty_cDB: Contig-U11698-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available telium discoideum cDNA clone:dda56i01, 5' ... 40 2.5 2 ( EV819108 ) BGBV-aae63e12.b1 Snail_EST_pSMART...1120_1( AF091120 |pid:none) Filobasidiella neoformans G-protei... 35 9.4 AM910987_83( AM910987 |pid:none) Plasmodium knowlesi strai... ) camceP048H06 camce Biomphalaria glabrata cDNA clo... 34 2.7 2 ( CP001056 ) Clostridium botulinum B str. E...id:none) Zea mays full-length cDNA clone ZM... 42 0.077 AE014298_1183( AE014298 |pid:none) Drosophila melanogaster chromos...943 |pid:none) Zebrafish DNA sequence from clone ... 37 1.9 AM746676_5137( AM746676 |pid:none) Sorangium cellulos

  20. Bugs as drugs, part two: worms, leeches, scorpions, snails, ticks, centipedes, and spiders.

    Science.gov (United States)

    Cherniack, E Paul

    2011-03-01

    In this second of a two-part series analyzing the evidence for the use of organisms as medicine, the use of a number of different "bugs" (worms, leeches, snails, ticks, centipedes, and spiders) is detailed. Several live organisms are used as treatments: leeches for plastic surgery and osteoarthritis and the helminths Trichuris suis and Necator americanus for inflammatory bowel disease. Leech saliva is the source of a number of anticoagulants, including the antithrombin agent hirudin and its synthetic analogues, which have been approved for human use. Predatory arthropods, such as certain species of snails, spiders, scorpions, centipedes, and ticks provide a trove of potential analgesic peptides in their venom. A synthetic analogue of a snail venom peptide, ziconotide, has been approved for human use and is used as an alternative to opioids in severe pain cases. Arthropods, such as ticks, have venom that contains anticoagulants and centipede venom has a protein that corrects abnormalities in lipid metabolism. PMID:21438646